chore: update maintainer list: Junjie Gao retired (#551)

Signed-off-by: Junjie Gao <junjiegao@microsoft.com>

.github/.codecov.yml

@@ -1,5 +1,21 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 coverage:
   status:
     project:
+      default:
+        target: 80%
+    patch:
       default:
         target: 80%

.github/ISSUE_TEMPLATE/bug-or-issue.yaml

@@ -0,0 +1,60 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: 🐛 Bug or Issue
+description: Something is not working as expected or not working at all! Report it here!
+labels: [bug, triage]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for taking the time to fill out this issue report. 🛑 Please check existing issues first before continuing: https://github.com/notaryproject/notation-go/issues
+  - type: textarea
+    id: verbatim
+    validations:
+      required: true
+    attributes:
+      label: "What is not working as expected?"
+      description: "In your own words, describe what the issue is."
+  - type: textarea
+    id: expect
+    validations:
+      required: true
+    attributes:
+      label: "What did you expect to happen?"
+      description: "A clear and concise description of what you expected to happen."
+  - type: textarea
+    id: reproduce
+    validations:
+      required: true
+    attributes:
+      label: "How can we reproduce it?"
+      description: "Detailed steps to reproduce the behavior, code snippets are welcome."
+  - type: textarea
+    id: environment
+    validations:
+      required: true
+    attributes:
+      label: Describe your environment 
+      description: "OS and Golang version"
+  - type: textarea
+    id: version
+    validations:
+      required: true
+    attributes:
+      label: What is the version of your notation-go Library?
+      description: "Check the `go.mod` file for the library version."
+  - type: markdown
+    attributes:
+      value: |
+        If you want to contribute to this project, we will be happy to guide you through the contribution process especially when you already have a good proposal or understanding of how to fix this issue. Join us at https://slack.cncf.io/ and choose #notary-project channel.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,18 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+blank_issues_enabled: false
+contact_links:
+  - name: Ask a question
+    url: https://slack.cncf.io/
+    about: "Join #notary-project channel on CNCF Slack"

.github/ISSUE_TEMPLATE/feature-request.yaml

@@ -0,0 +1,53 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: 🚀 Feature Request
+description: Suggest an idea for this project.
+labels: [enhancement, triage]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for taking the time to suggest a useful feature for the project!
+  - type: textarea
+    id: problem
+    validations:
+      required: true
+    attributes:
+      label: "Is your feature request related to a problem?"
+      description: "A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]"
+  - type: textarea
+    id: solution
+    validations:
+      required: true
+    attributes:
+      label: "What solution do you propose?"
+      description: "A clear and concise description of what you want to happen."
+  - type: textarea
+    id: alternatives
+    validations:
+      required: true
+    attributes:
+      label: "What alternatives have you considered?"
+      description: "A clear and concise description of any alternative solutions or features you've considered."
+  - type: textarea
+    id: context
+    validations:
+      required: false
+    attributes:
+      label: "Any additional context?"
+      description: "Add any other context or screenshots about the feature request here."
+  - type: markdown
+    attributes:
+      value: |
+        If you want to contribute to this project, we will be happy to guide you through the contribution process especially when you already have a good proposal or understanding of how to improve the functionality. Join us at https://slack.cncf.io/ and choose #notary-project channel.

.github/dependabot.yml

@@ -1,3 +1,16 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 version: 2
 updates:
   - package-ecosystem: "gomod"

.github/licenserc.yml

@@ -0,0 +1,44 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+header:
+  license:
+    spdx-id: Apache-2.0
+    content: |
+      Copyright The Notary Project Authors.
+      Licensed under the Apache License, Version 2.0 (the "License");
+      you may not use this file except in compliance with the License.
+      You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+      Unless required by applicable law or agreed to in writing, software
+      distributed under the License is distributed on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+      See the License for the specific language governing permissions and
+      limitations under the License.
+
+  paths-ignore:
+    - '**/*.md'
+    - 'CODEOWNERS'
+    - 'LICENSE'
+    - 'MAINTAINERS'
+    - 'go.mod'
+    - 'go.sum'
+    - '**/testdata/**'
+
+  comment: on-failure
+
+dependency:
+  files:
+    - go.mod

.github/workflows/add-to-project.yml

@@ -1,3 +1,16 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 on:
   issues:
     types:

.github/workflows/build.yml

@@ -1,11 +1,30 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 name: build
 
 on:
   push:
-    branches: main
+    branches: 
+      - main
+      - release-*
   pull_request:
-    branches: main
+    branches:
+      - main
+      - release-*
 
 jobs:
   build:
     uses: notaryproject/notation-core-go/.github/workflows/reusable-build.yml@main
+    secrets:
+      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/codeql.yml

@@ -1,10 +1,27 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 name: "CodeQL"
 
 on:
   push:
-    branches: main
+    branches: 
+      - main
+      - release-*
   pull_request:
-    branches: main
+    branches:
+      - main
+      - release-*
   schedule:
     - cron: '29 2 * * 5'
 

.github/workflows/license-checker.yml

@@ -0,0 +1,32 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: License Checker
+
+on:
+  push:
+    branches: 
+      - main
+      - release-*
+  pull_request:
+    branches:
+      - main
+      - release-*
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  check-license:
+    uses: notaryproject/notation-core-go/.github/workflows/reusable-license-checker.yml@main

.github/workflows/stale.yml

@@ -0,0 +1,33 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: "Close stale issues and PRs"
+on:
+  schedule:
+    - cron: "30 1 * * *"
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v9
+        with:
+          stale-issue-message: "This issue is stale because it has been opened for 60 days with no activity. Remove stale label or comment. Otherwise, it will be closed in 30 days."
+          stale-pr-message: "This PR is stale because it has been opened for 45 days with no activity. Remove stale label or comment. Otherwise, it will be closed in 30 days."
+          close-issue-message: "Issue closed due to no activity in the past 30 days."
+          close-pr-message: "PR closed due to no activity in the past 30 days."
+          days-before-issue-stale: 60
+          days-before-pr-stale: 45
+          days-before-issue-close: 30
+          days-before-pr-close: 30
+          exempt-all-milestones: true

.gitignore

@@ -1,3 +1,16 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # Code Editors
 .vscode
 .idea
@@ -5,4 +18,7 @@
 *.sublime-workspace
 
 # Custom
-coverage.txt
+coverage.txt
+
+# tmp directory was generated by example_remoteVerify_test.go 
+tmp/

CODEOWNERS

@@ -1,3 +1,3 @@
 # Repo-Level Owners (in alphabetical order)
 # Note: This is only for the notaryproject/notation-go repo
-* @gokarnm @JeyJeyGao @justincormack @niazfk @patrickzheng200 @priteshbandi @rgnote @shizhMSFT @stevelasker
+* @gokarnm @niazfk @priteshbandi @rgnote @shizhMSFT @toddysm @Two-Hearts @vaninrao10 @yizha1

MAINTAINERS

@@ -1,14 +1,21 @@
 # Org-Level Maintainers (in alphabetical order)
 # Pattern: [First Name] [Last Name] <[Email Address]> ([GitHub Handle])
-Justin Cormack <justin.cormack@docker.com> (@justincormack)
 Niaz Khan <niazfk@amazon.com> (@niazfk)
-Steve Lasker <StevenLasker@hotmail.com> (@stevelasker)
+Pritesh Bandi <priteshbandi@gmail.com> (@priteshbandi)
+Shiwei Zhang <shizh@microsoft.com> (@shizhMSFT)
+Toddy Mladenov <toddysm@gmail.com> (@toddysm)
+Vani Rao <vaninrao@amazon.com> (@vaninrao10)
+Yi Zha <yizha1@microsoft.com> (@yizha1)
 
 # Repo-Level Maintainers (in alphabetical order)
 # Note: This is for the notaryproject/notation-go repo
-Junjie Gao <junjiegao@microsoft.com> (@JeyJeyGao)
 Milind Gokarn <gokarnm@amazon.com> (@gokarnm)
-Patrick Zheng <patrickzheng@microsoft.com> (@patrickzheng200)
-Pritesh Bandi <priteshbandi@gmail.com> (@priteshbandi)
+Patrick Zheng <patrickzheng@microsoft.com> (@Two-Hearts)
 Rakesh Gariganti <garigant@amazon.com> (@rgnote)
-Shiwei Zhang <shizh@microsoft.com> (@shizhMSFT)
+
+# Emeritus Org Maintainers (in alphabetical order)
+Justin Cormack <justin.cormack@docker.com> (@justincormack)
+Steve Lasker <StevenLasker@hotmail.com> (@stevelasker)
+
+# Emeritus Repo-Level Maintainers (in alphabetical order)
+Junjie Gao <junjiegao@microsoft.com> (@JeyJeyGao)

Makefile

@@ -1,3 +1,16 @@
+# Copyright The Notary Project Authors.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 .PHONY: help
 help:
 	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-25s\033[0m %s\n", $$1, $$2}'
@@ -16,7 +29,7 @@ clean:
 .PHONY: check-line-endings
 check-line-endings: ## check line endings
 	! find . -name "*.go" -type f -exec file "{}" ";" | grep CRLF
-	! find scripts -name "*.sh" -type f -exec file "{}" ";" | grep CRLF
+	! find . -name "*.sh" -type f -exec file "{}" ";" | grep CRLF
 
 .PHONY: fix-line-endings
 fix-line-endings: ## fix line endings

README.md

@@ -1,20 +1,28 @@
-# Notation
+# notation-go
 
 [![Build Status](https://github.com/notaryproject/notation-go/actions/workflows/build.yml/badge.svg?event=push&branch=main)](https://github.com/notaryproject/notation-go/actions/workflows/build.yml?query=workflow%3Abuild+event%3Apush+branch%3Amain)
-[![codecov](https://codecov.io/gh/notaryproject/notation-go/branch/main/graph/badge.svg)](https://codecov.io/gh/notaryproject/notation-go)
+[![Codecov](https://codecov.io/gh/notaryproject/notation-go/branch/main/graph/badge.svg)](https://codecov.io/gh/notaryproject/notation-go)
 [![Go Reference](https://pkg.go.dev/badge/github.com/notaryproject/notation-go.svg)](https://pkg.go.dev/github.com/notaryproject/notation-go@main)
+[![OpenSSF Scorecard](https://api.scorecard.dev/projects/github.com/notaryproject/notation-go/badge)](https://scorecard.dev/viewer/?uri=github.com/notaryproject/notation-go)
 
-A collection of libraries for supporting Notation sign, verify, push, pull of oci artifacts. Based on Notary V2 standard.
+notation-go contains libraries for signing and verification of artifacts as per [Notary Project specifications](https://github.com/notaryproject/specifications). notation-go is being used by [notation](https://github.com/notaryproject/notation) CLI for signing and verifying artifacts.
+
+notation-go reached a stable release as of July 2023 and continues to be actively developed and maintained.
+
+Please visit [README](https://github.com/notaryproject/.github/blob/main/README.md) to know more about Notary Project.
+
+> [!NOTE]
+> The Notary Project documentation is available [here](https://notaryproject.dev/docs/).
 
 ## Table of Contents
-- [Core Documents](#core-documents)
+
+- [Documentation](#documentation)
 - [Code of Conduct](#code-of-conduct)
 - [License](#license)
+ 
+## Documentation
 
-## Core Documents
-
-* [Governance for Notation](https://github.com/notaryproject/notary/blob/master/GOVERNANCE.md)
-* [Maintainers and reviewers list](https://github.com/notaryproject/notary/blob/master/MAINTAINERS)
+Library documentation is available at [Go Reference](https://pkg.go.dev/github.com/notaryproject/notation-go).
 
 ## Code of Conduct
 

RELEASE_CHECKLIST.md

@@ -0,0 +1,36 @@
+# Release Checklist
+
+## Overview
+
+This document describes the checklist to publish a release for notation-go.
+
+## Release Process from main
+
+1. Check if there are any security vulnerabilities fixed and security advisories published before a release. Security advisories should be linked on the release notes.
+2. Determine a [SemVer2](https://semver.org/)-valid version prefixed with the letter `v` for release. For example, `version="v1.0.0-rc.1"`.
+3. If there is new release in [notation-core-go](https://github.com/notaryproject/notation-core-go) library that are required to be upgraded in notation-go, update the dependency versions in the follow `go.mod` and `go.sum` files of notation-go:
+    - [go.mod](go.mod), [go.sum](go.sum)
+4. Open a bump up PR and submit the changes in step 3 to the notation-go repository.
+5. After PR from step 4 is merged. Create another PR to update the value of `signingAgent` defined in file [signer/signer.go](signer/signer.go) with `notation-go/<version>`, where `<version>` is `$version` from step 2 without the `v` prefix. For example, `notation-go/1.0.0-rc.1`. The commit message MUST follow the [conventional commit](https://www.conventionalcommits.org/en/v1.0.0/) and could be `bump: release $version`. Record the digest of that commit as `<commit_digest>`. This PR is also used for voting purpose of the new release. Add the link of change logs and repo-level maintainer list in the PR's description. The PR title could be `bump: release $version`. Make sure to reach a majority of approvals from the [repo-level maintainers](MAINTAINERS) before merging it. This PR MUST be merged using [Create a merge commit](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/about-merge-methods-on-github) method in GitHub.
+6. After the voting PR is merged, execute `git clone https://github.com/notaryproject/notation-go.git` to clone the repository to your local file system.
+7. Enter the cloned repository and execute `git checkout <commit_digest>` to switch to the specified branch based on the voting result.
+8. Create a tag by running `git tag -am $version $version -s`.
+9. Run `git tag` and ensure the desired tag name in the list looks correct, then push the new tag directly to the repository by running `git push origin $version`.
+10. On notation-go GitHub page, goto [Tags](https://github.com/notaryproject/notation-go/tags). Your newly pushed tag should be shown on the top. Create a new release from the tag. Generate the release notes, revise the release description and change logs, and publish the release.
+11. Announce the new release in the Notary Project community.
+
+## Release Process from a release branch
+
+1. Check if there are any security vulnerabilities fixed and security advisories published before a release. Security advisories should be linked on the release notes.
+2. Determine a [SemVer2](https://semver.org/)-valid version prefixed with the letter `v` for release. For example, `version="v1.2.0-rc.1"`.
+3. If a new release branch is needed, from main branch's [commit list](https://github.com/notaryproject/notation-go/commits/main/), find the commit that you want to cut the release. Click `<>` (Browse repository at this point). Create branch with name `release-<version>` from the commit, where `<version>` is `$version` from step 2 with the major and minor versions only. For example `release-1.2`. If the release branch already exists, skip this step.
+4. If there is new release in [notation-core-go](https://github.com/notaryproject/notation-core-go) library that are required to be upgraded in notation-go, update the dependency versions in the follow `go.mod` and `go.sum` files of notation-go:
+    - [go.mod](go.mod), [go.sum](go.sum)
+5. Open a bump up PR and submit the changes in step 4 to the release branch. 
+6. After PR from step 5 is merged. Create another PR to update the value of `signingAgent` defined in file `signer/signer.go` with `notation-go/<version>`, where `<version>` is `$version` from step 2 without the `v` prefix. For example, `notation-go/1.2.0-rc.1`. The commit message MUST follow the [conventional commit](https://www.conventionalcommits.org/en/v1.0.0/) and could be `bump: release $version`. Record the digest of that commit as `<commit_digest>`. This PR is also used for voting purpose of the new release. Add the link of change logs and repo-level maintainer list in the PR's description. The PR title could be `bump: release $version`. Make sure to reach a majority of approvals from the [repo-level maintainers](MAINTAINERS) before merging it. This PR MUST be merged using [Create a merge commit](https://docs.github.com/en/repositories/configuring-branches-and-merges-in-your-repository/configuring-pull-request-merges/about-merge-methods-on-github) method in GitHub.
+7. After the voting PR is merged, execute `git clone https://github.com/notaryproject/notation-go.git` to clone the repository to your local file system.
+8. Enter the cloned repository and execute `git checkout <commit_digest>` to switch to the specified branch based on the voting result.
+9. Create a tag by running `git tag -am $version $version -s`.
+10. Run `git tag` and ensure the desired tag name in the list looks correct, then push the new tag directly to the repository by running `git push origin $version`.
+11. On notation-go GitHub page, goto [Tags](https://github.com/notaryproject/notation-go/tags). Your newly pushed tag should be shown on the top. Create a new release from the tag. Generate the release notes, revise the release description and change logs, and publish the release.
+12. Announce the new release in the Notary Project community.

config/base.go

@@ -1,7 +1,22 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package config
 
 import (
 	"encoding/json"
+	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 
@@ -28,7 +43,22 @@ func save(filePath string, cfg interface{}) error {
 
 // load reads file, parses json and stores in cfg struct
 func load(filePath string, cfg interface{}) error {
-	file, err := dir.ConfigFS().Open(filePath)
+	path, err := dir.ConfigFS().SysPath(filePath)
+	if err != nil {
+		return err
+	}
+
+	// throw error if path is a directory or is a symlink or does not exist.
+	fileInfo, err := os.Lstat(path)
+	if err != nil {
+		return err
+	}
+	mode := fileInfo.Mode()
+	if mode.IsDir() || mode&fs.ModeSymlink != 0 {
+		return fmt.Errorf("%q is not a regular file (symlinks are not supported)", path)
+	}
+
+	file, err := os.Open(path)
 	if err != nil {
 		return err
 	}

config/base_test.go

@@ -0,0 +1,51 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/notaryproject/notation-go/dir"
+)
+
+func TestLoadNonExistentFile(t *testing.T) {
+	dir.UserConfigDir = "testdata/valid"
+
+	var config string
+	err := load("non-existent", &config)
+	if err == nil {
+		t.Fatalf("load() expected error but not found")
+	}
+}
+
+func TestLoadSymlink(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping test on Windows")
+	}
+	root := t.TempDir()
+	dir.UserConfigDir = root
+	fileName := "symlink"
+	os.Symlink("testdata/valid/config.json", filepath.Join(root, fileName))
+
+	expectedError := fmt.Sprintf("\"%s/%s\" is not a regular file (symlinks are not supported)", dir.UserConfigDir, fileName)
+	var config string
+	err := load(fileName, &config)
+	if err != nil && err.Error() != expectedError {
+		t.Fatalf("load() expected error= %s but found= %v", expectedError, err)
+	}
+}

config/config.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package config provides the ability to load and save config.json and
 // signingkeys.json.
 package config

config/config_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package config
 
 import (
@@ -38,3 +51,15 @@ func TestSaveFile(t *testing.T) {
 		t.Fatal("save config file failed.")
 	}
 }
+
+func TestLoadNonExistedConfig(t *testing.T) {
+	dir.UserConfigDir = "./testdata/non-existed"
+	got, err := LoadConfig()
+	if err != nil {
+		t.Fatalf("LoadConfig() error. err = %v", err)
+	}
+
+	if !reflect.DeepEqual(got, NewConfig()) {
+		t.Errorf("loadFile() = %v, want %v", got, NewConfig())
+	}
+}

config/errors.go

@@ -0,0 +1,35 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"errors"
+	"fmt"
+)
+
+// ErrKeyNameEmpty is used when key name is empty.
+var ErrKeyNameEmpty = errors.New("key name cannot be empty")
+
+// KeyNotFoundError is used when key is not found in the signingkeys.json file.
+type KeyNotFoundError struct {
+	KeyName string
+}
+
+// Error returns the error message.
+func (e KeyNotFoundError) Error() string {
+	if e.KeyName != "" {
+		return fmt.Sprintf("signing key %s not found", e.KeyName)
+	}
+	return "signing key not found"
+}

config/errors_test.go

@@ -0,0 +1,28 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import "testing"
+
+func TestErrorKeyNotFound(t *testing.T) {
+	e := KeyNotFoundError{}
+	if e.Error() != "signing key not found" {
+		t.Fatalf("ErrorKeyNotFound.Error() = %v, want %v", e.Error(), "signing key not found")
+	}
+
+	e = KeyNotFoundError{KeyName: "testKey"}
+	if e.Error() != `signing key testKey not found` {
+		t.Fatalf("ErrorKeyNotFound.Error() = %v, want %v", e.Error(), "signing key testKey not found")
+	}
+}

config/keys.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package config
 
 import (
@@ -37,9 +50,6 @@ type KeySuite struct {
 	*ExternalKey
 }
 
-var errorKeyNameEmpty = errors.New("key name cannot be empty")
-var errKeyNotFound = errors.New("signing key not found")
-
 // SigningKeys reflects the signingkeys.json file.
 type SigningKeys struct {
 	Default *string    `json:"default,omitempty"`
@@ -54,13 +64,12 @@ func NewSigningKeys() *SigningKeys {
 // Add adds new signing key
 func (s *SigningKeys) Add(name, keyPath, certPath string, markDefault bool) error {
 	if name == "" {
-		return errorKeyNameEmpty
+		return ErrKeyNameEmpty
 	}
 	_, err := tls.LoadX509KeyPair(certPath, keyPath)
 	if err != nil {
 		return err
 	}
-
 	ks := KeySuite{
 		Name: name,
 		X509KeyPair: &X509KeyPair{
@@ -75,25 +84,20 @@ func (s *SigningKeys) Add(name, keyPath, certPath string, markDefault bool) erro
 func (s *SigningKeys) AddPlugin(ctx context.Context, keyName, id, pluginName string, pluginConfig map[string]string, markDefault bool) error {
 	logger := log.GetLogger(ctx)
 	logger.Debugf("Adding key with name %v and plugin name %v", keyName, pluginName)
-
 	if keyName == "" {
-		return errorKeyNameEmpty
+		return ErrKeyNameEmpty
 	}
-
 	if id == "" {
 		return errors.New("missing key id")
 	}
-
 	if pluginName == "" {
 		return errors.New("plugin name cannot be empty")
 	}
-
 	mgr := plugin.NewCLIManager(dir.PluginFS())
 	_, err := mgr.Get(ctx, pluginName)
 	if err != nil {
 		return err
 	}
-
 	ks := KeySuite{
 		Name: keyName,
 		ExternalKey: &ExternalKey{
@@ -102,7 +106,6 @@ func (s *SigningKeys) AddPlugin(ctx context.Context, keyName, id, pluginName str
 			PluginConfig: pluginConfig,
 		},
 	}
-
 	if err = s.add(ks, markDefault); err != nil {
 		logger.Error("Failed to add key with error: %v", err)
 		return err
@@ -114,14 +117,12 @@ func (s *SigningKeys) AddPlugin(ctx context.Context, keyName, id, pluginName str
 // Get returns signing key for the given name
 func (s *SigningKeys) Get(keyName string) (KeySuite, error) {
 	if keyName == "" {
-		return KeySuite{}, errorKeyNameEmpty
+		return KeySuite{}, ErrKeyNameEmpty
 	}
-
 	idx := slices.IndexIsser(s.Keys, keyName)
 	if idx < 0 {
-		return KeySuite{}, errKeyNotFound
+		return KeySuite{}, KeyNotFoundError{KeyName: keyName}
 	}
-
 	return s.Keys[idx], nil
 }
 
@@ -129,9 +130,8 @@ func (s *SigningKeys) Get(keyName string) (KeySuite, error) {
 func (s *SigningKeys) GetDefault() (KeySuite, error) {
 	if s.Default == nil {
 		return KeySuite{}, errors.New("default signing key not set." +
-			" Please set default singing key or specify a key name")
+			" Please set default signing key or specify a key name")
 	}
-
 	return s.Get(*s.Default)
 }
 
@@ -140,12 +140,11 @@ func (s *SigningKeys) Remove(keyName ...string) ([]string, error) {
 	var deletedNames []string
 	for _, name := range keyName {
 		if name == "" {
-			return deletedNames, errorKeyNameEmpty
+			return deletedNames, ErrKeyNameEmpty
 		}
-
 		idx := slices.IndexIsser(s.Keys, name)
 		if idx < 0 {
-			return deletedNames, errors.New(name + ": not found")
+			return deletedNames, KeyNotFoundError{KeyName: name}
 		}
 		s.Keys = slices.Delete(s.Keys, idx)
 		deletedNames = append(deletedNames, name)
@@ -159,13 +158,11 @@ func (s *SigningKeys) Remove(keyName ...string) ([]string, error) {
 // UpdateDefault updates default signing key
 func (s *SigningKeys) UpdateDefault(keyName string) error {
 	if keyName == "" {
-		return errorKeyNameEmpty
+		return ErrKeyNameEmpty
 	}
-
 	if !slices.ContainsIsser(s.Keys, keyName) {
-		return fmt.Errorf("key with name '%s' not found", keyName)
+		return KeyNotFoundError{KeyName: keyName}
 	}
-
 	s.Default = &keyName
 	return nil
 }
@@ -176,11 +173,9 @@ func (s *SigningKeys) Save() error {
 	if err != nil {
 		return err
 	}
-
 	if err := validateKeys(s); err != nil {
 		return err
 	}
-
 	return save(path, s)
 }
 
@@ -195,11 +190,9 @@ func LoadSigningKeys() (*SigningKeys, error) {
 		}
 		return nil, err
 	}
-
 	if err := validateKeys(&config); err != nil {
 		return nil, err
 	}
-
 	return &config, nil
 }
 
@@ -211,11 +204,9 @@ func LoadExecSaveSigningKeys(fn func(keys *SigningKeys) error) error {
 	if err != nil {
 		return err
 	}
-
 	if err := fn(signingKeys); err != nil {
 		return err
 	}
-
 	return signingKeys.Save()
 }
 
@@ -228,12 +219,10 @@ func (s *SigningKeys) add(key KeySuite, markDefault bool) error {
 	if slices.ContainsIsser(s.Keys, key.Name) {
 		return fmt.Errorf("signing key with name %q already exists", key.Name)
 	}
-
 	s.Keys = append(s.Keys, key)
 	if markDefault {
 		s.Default = &key.Name
 	}
-
 	return nil
 }
 
@@ -249,17 +238,14 @@ func validateKeys(config *SigningKeys) error {
 		}
 		uniqueKeyNames.Add(key.Name)
 	}
-
 	if config.Default != nil {
 		defaultKey := *config.Default
 		if len(defaultKey) == 0 {
 			return fmt.Errorf("malformed %s: default key name cannot be empty", dir.PathSigningKeys)
 		}
-
 		if !uniqueKeyNames.Contains(defaultKey) {
 			return fmt.Errorf("malformed %s: default key '%s' not found", dir.PathSigningKeys, defaultKey)
 		}
 	}
-
 	return nil
 }

config/keys_test.go

@@ -1,9 +1,23 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package config
 
 import (
 	"context"
 	"crypto/x509"
 	"encoding/pem"
+	"errors"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -54,11 +68,11 @@ func TestLoadSigningKeysInfo(t *testing.T) {
 		}
 
 		if !reflect.DeepEqual(sampleSigningKeysInfo.Default, got.Default) {
-			t.Fatal("singingKeysInfo test failed.")
+			t.Fatal("signingKeysInfo test failed.")
 		}
 
 		if !reflect.DeepEqual(sampleSigningKeysInfo.Keys, got.Keys) {
-			t.Fatal("singingKeysInfo test failed.")
+			t.Fatal("signingKeysInfo test failed.")
 		}
 	})
 
@@ -297,14 +311,22 @@ func TestGet(t *testing.T) {
 	})
 
 	t.Run("NonExistent", func(t *testing.T) {
-		if _, err := sampleSigningKeysInfo.Get("nonExistent"); err == nil {
+		_, err := sampleSigningKeysInfo.Get("nonExistent")
+		if err == nil {
 			t.Error("expected Get() to fail for nonExistent key name")
 		}
+		if !errors.Is(err, KeyNotFoundError{KeyName: "nonExistent"}) {
+			t.Error("expected Get() to return ErrorKeyNotFound")
+		}
 	})
 
-	t.Run("InvalidName", func(t *testing.T) {
-		if _, err := sampleSigningKeysInfo.Get(""); err == nil {
-			t.Error("expected Get() to fail for invalid key name")
+	t.Run("EmptyName", func(t *testing.T) {
+		_, err := sampleSigningKeysInfo.Get("")
+		if err == nil {
+			t.Error("expected Get() to fail for empty key name")
+		}
+		if !errors.Is(err, ErrKeyNameEmpty) {
+			t.Error("expected Get() to return ErrorKeyNameEmpty")
 		}
 	})
 }
@@ -345,14 +367,22 @@ func TestUpdateDefault(t *testing.T) {
 	})
 
 	t.Run("NonExistent", func(t *testing.T) {
-		if err := sampleSigningKeysInfo.UpdateDefault("nonExistent"); err == nil {
+		err := sampleSigningKeysInfo.UpdateDefault("nonExistent")
+		if err == nil {
 			t.Error("expected Get() to fail for nonExistent key name")
 		}
+		if !errors.Is(err, KeyNotFoundError{KeyName: "nonExistent"}) {
+			t.Error("expected Get() to return ErrorKeyNotFound")
+		}
 	})
 
-	t.Run("InvalidName", func(t *testing.T) {
-		if err := sampleSigningKeysInfo.UpdateDefault(""); err == nil {
-			t.Error("expected Get() to fail for invalid key name")
+	t.Run("EmptyName", func(t *testing.T) {
+		err := sampleSigningKeysInfo.UpdateDefault("")
+		if err == nil {
+			t.Error("expected Get() to fail for empty key name")
+		}
+		if !errors.Is(err, ErrKeyNameEmpty) {
+			t.Error("expected Get() to return ErrorKeyNameEmpty")
 		}
 	})
 }
@@ -369,21 +399,28 @@ func TestRemove(t *testing.T) {
 		if _, err := testSigningKeysInfo.Get(testKeyName); err == nil {
 			t.Error("Delete() filed to delete key")
 		}
-
 		if keys[0] != testKeyName {
 			t.Error("Delete() deleted key name mismatch")
 		}
 	})
 
 	t.Run("NonExistent", func(t *testing.T) {
-		if _, err := testSigningKeysInfo.Remove(testKeyName); err == nil {
+		_, err := testSigningKeysInfo.Remove("nonExistent")
+		if err == nil {
 			t.Error("expected Get() to fail for nonExistent key name")
 		}
+		if !errors.Is(err, KeyNotFoundError{KeyName: "nonExistent"}) {
+			t.Error("expected Get() to return ErrorKeyNotFound")
+		}
 	})
 
-	t.Run("InvalidName", func(t *testing.T) {
-		if _, err := testSigningKeysInfo.Remove(""); err == nil {
-			t.Error("expected Get() to fail for invalid key name")
+	t.Run("EmptyName", func(t *testing.T) {
+		_, err := testSigningKeysInfo.Remove("")
+		if err == nil {
+			t.Error("expected Get() to fail for empty key name")
+		}
+		if !errors.Is(err, ErrKeyNameEmpty) {
+			t.Error("expected Get() to return ErrorKeyNameEmpty")
 		}
 	})
 }

dir/fs.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package dir
 
 import (
@@ -38,10 +51,17 @@ func NewSysFS(root string) SysFS {
 
 // ConfigFS is the config SysFS
 func ConfigFS() SysFS {
-	return NewSysFS(UserConfigDir)
+	return NewSysFS(userConfigDirPath())
 }
 
 // PluginFS is the plugin SysFS
 func PluginFS() SysFS {
-	return NewSysFS(filepath.Join(UserLibexecDir, PathPlugins))
+	return NewSysFS(filepath.Join(userLibexecDirPath(), PathPlugins))
+}
+
+// CacheFS is the cache SysFS.
+//
+// To get the root of crl file cache, use `CacheFS().SysFS(PathCRLCache)`.
+func CacheFS() SysFS {
+	return NewSysFS(userCacheDirPath())
 }

dir/fs_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package dir
 
 import (
@@ -6,7 +19,7 @@ import (
 	"testing"
 )
 
-func Test_sysFS_SysPath(t *testing.T) {
+func TestSysFS_SysPath(t *testing.T) {
 	wantPath := filepath.FromSlash("/path/notation/config.json")
 	fsys := NewSysFS("/path/notation")
 	path, err := fsys.SysPath(PathConfigFile)
@@ -18,7 +31,7 @@ func Test_sysFS_SysPath(t *testing.T) {
 	}
 }
 
-func Test_OsFs(t *testing.T) {
+func TestOsFs(t *testing.T) {
 	wantData := []byte("data")
 	fsys := NewSysFS("./testdata")
 
@@ -36,3 +49,36 @@ func Test_OsFs(t *testing.T) {
 		t.Fatalf("SysFS read failed. got data = %v, want %v", data, wantData)
 	}
 }
+
+func TestConfigFS(t *testing.T) {
+	configFS := ConfigFS()
+	path, err := configFS.SysPath(PathConfigFile)
+	if err != nil {
+		t.Fatalf("SysPath() failed. err = %v", err)
+	}
+	if path != filepath.Join(UserConfigDir, PathConfigFile) {
+		t.Fatalf(`SysPath() failed. got: %q, want: %q`, path, filepath.Join(UserConfigDir, PathConfigFile))
+	}
+}
+
+func TestPluginFS(t *testing.T) {
+	pluginFS := PluginFS()
+	path, err := pluginFS.SysPath("plugin")
+	if err != nil {
+		t.Fatalf("SysPath() failed. err = %v", err)
+	}
+	if path != filepath.Join(userLibexecDirPath(), PathPlugins, "plugin") {
+		t.Fatalf(`SysPath() failed. got: %q, want: %q`, path, filepath.Join(userLibexecDirPath(), PathPlugins, "plugin"))
+	}
+}
+
+func TestCRLFileCacheFS(t *testing.T) {
+	cacheFS := CacheFS()
+	path, err := cacheFS.SysPath(PathCRLCache)
+	if err != nil {
+		t.Fatalf("SysPath() failed. err = %v", err)
+	}
+	if path != filepath.Join(UserCacheDir, PathCRLCache) {
+		t.Fatalf(`SysPath() failed. got: %q, want: %q`, path, UserConfigDir)
+	}
+}

dir/path.go

@@ -1,5 +1,18 @@
-// package dir implements Notation directory structure.
-// [directory spec]: https://github.com/notaryproject/notation/blob/main/specs/directory.md
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package dir implements Notation directory structure.
+// [directory spec]: https://notaryproject.dev/docs/user-guides/how-to/directory-structure/
 //
 // Example:
 //
@@ -18,7 +31,7 @@
 //   - Set custom configurations directory:
 //     dir.UserConfigDir = '/path/to/configurations/'
 //
-// Only user level directory is supported for RC.1, and system level directory
+// Only user level directory is supported, and system level directory
 // may be added later.
 package dir
 
@@ -31,6 +44,7 @@ import (
 var (
 	UserConfigDir  string // Absolute path of user level {NOTATION_CONFIG}
 	UserLibexecDir string // Absolute path of user level {NOTATION_LIBEXEC}
+	UserCacheDir   string // Absolute path of user level {NOTATION_CACHE}
 )
 
 const (
@@ -44,10 +58,15 @@ const (
 	PathConfigFile = "config.json"
 	// PathSigningKeys is the signingkeys file relative path.
 	PathSigningKeys = "signingkeys.json"
-	// PathTrustPolicy is the trust policy file relative path.
+	// PathTrustPolicy is the OCI trust policy file relative path.
+	//
+	// Deprecated: PathTrustPolicy exists for historical compatibility and should not be used.
+	// To get OCI trust policy path, use PathOCITrustPolicy.
 	PathTrustPolicy = "trustpolicy.json"
-	// PathPlugins is the plugins directory relative path.
-	PathPlugins = "plugins"
+	// PathOCITrustPolicy is the OCI trust policy file relative path.
+	PathOCITrustPolicy = "trustpolicy.oci.json"
+	// PathBlobTrustPolicy is the Blob trust policy file relative path.
+	PathBlobTrustPolicy = "trustpolicy.blob.json"
 	// LocalKeysDir is the directory name for local key relative path.
 	LocalKeysDir = "localkeys"
 	// LocalCertificateExtension defines the extension of the certificate files.
@@ -58,23 +77,62 @@ const (
 	TrustStoreDir = "truststore"
 )
 
-var userConfigDir = os.UserConfigDir // for unit test
+// The relative path to {NOTATION_LIBEXEC}
+const (
+	// PathPlugins is the plugins directory relative path.
+	PathPlugins = "plugins"
+)
 
-func init() {
-	loadUserPath()
+// The relative path to {NOTATION_CACHE}
+const (
+	// PathCRLCache is the crl file cache directory relative path.
+	PathCRLCache = "crl"
+)
+
+// for unit tests
+var (
+	userConfigDir = os.UserConfigDir
+
+	userCacheDir = os.UserCacheDir
+)
+
+// userConfigDirPath returns the user level {NOTATION_CONFIG} path.
+func userConfigDirPath() string {
+	if UserConfigDir == "" {
+		userDir, err := userConfigDir()
+		if err != nil {
+			// fallback to current directory
+			UserConfigDir = "." + notation
+			return UserConfigDir
+		}
+		// set user config
+		UserConfigDir = filepath.Join(userDir, notation)
+	}
+	return UserConfigDir
 }
 
-// loadUserPath function defines UserConfigDir and UserLibexecDir.
-func loadUserPath() {
-	// set user config
-	userDir, err := userConfigDir()
-	if err != nil {
-		panic(err)
+// userLibexecDirPath returns the user level {NOTATION_LIBEXEC} path.
+func userLibexecDirPath() string {
+	if UserLibexecDir == "" {
+		// set user libexec
+		UserLibexecDir = userConfigDirPath()
 	}
-	UserConfigDir = filepath.Join(userDir, notation)
+	return UserLibexecDir
+}
 
-	// set user libexec
-	UserLibexecDir = UserConfigDir
+// userCacheDirPath returns the user level {NOTATION_CACHE} path.
+func userCacheDirPath() string {
+	if UserCacheDir == "" {
+		userDir, err := userCacheDir()
+		if err != nil {
+			// fallback to current directory
+			UserCacheDir = filepath.Join("."+notation, "cache")
+			return UserCacheDir
+		}
+		// set user cache
+		UserCacheDir = filepath.Join(userDir, notation)
+	}
+	return UserCacheDir
 }
 
 // LocalKeyPath returns the local key and local cert relative paths.
@@ -87,7 +145,7 @@ func LocalKeyPath(name string) (keyPath, certPath string) {
 //
 // items includes named-store and cert-file names.
 // the directory follows the pattern of
-// {NOTATION_CONFIG}/truststore/x509/{named-store}/{cert-file}
+// {NOTATION_CONFIG}/truststore/x509/{store-type}/{named-store}/{cert-file}
 func X509TrustStoreDir(items ...string) string {
 	pathItems := []string{TrustStoreDir, "x509"}
 	pathItems = append(pathItems, items...)

dir/path_test.go

@@ -1,30 +1,83 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package dir
 
 import (
+	"os"
 	"path/filepath"
 	"testing"
 )
 
-func mockGetUserConfig() (string, error) {
+func mockUserPath() (string, error) {
 	return "/path/", nil
 }
 
-func Test_loadPath(t *testing.T) {
-	wantDir := filepath.FromSlash("/path/notation")
-	userConfigDir = mockGetUserConfig
-	loadUserPath()
-	if UserConfigDir != wantDir {
-		t.Fatalf(`loadPath() UserConfigDir is incorrect. got: %q, want: %q`, UserConfigDir, wantDir)
-	}
+func setup() {
+	UserConfigDir = ""
+	UserLibexecDir = ""
+	UserCacheDir = ""
+}
 
-	if UserLibexecDir != UserConfigDir {
-		t.Fatalf(`loadPath() UserLibexecDir is incorrect. got: %q, want: %q`, UserLibexecDir, wantDir)
+func Test_UserConfigDirPath(t *testing.T) {
+	userConfigDir = mockUserPath
+	setup()
+	got := userConfigDirPath()
+	if got != "/path/notation" {
+		t.Fatalf(`UserConfigDirPath() = %q, want "/path/notation"`, got)
+	}
+}
+
+func Test_NoHomeVariable(t *testing.T) {
+	t.Setenv("HOME", "")
+	t.Setenv("XDG_CONFIG_HOME", "")
+	t.Setenv("XDG_CACHE_HOME", "")
+	setup()
+	userConfigDir = os.UserConfigDir
+	got := userConfigDirPath()
+	if got != ".notation" {
+		t.Fatalf(`userConfigDirPath() = %q, want ".notation"`, got)
+	}
+	got = userCacheDirPath()
+	want := filepath.Join("."+notation, "cache")
+	if got != want {
+		t.Fatalf(`userCacheDirPath() = %q, want %q`, got, want)
+	}
+}
+
+func Test_UserLibexecDirPath(t *testing.T) {
+	userConfigDir = mockUserPath
+	setup()
+	got := userLibexecDirPath()
+	if got != "/path/notation" {
+		t.Fatalf(`UserConfigDirPath() = %q, want "/path/notation"`, got)
+	}
+}
+
+func Test_UserCacheDirPath(t *testing.T) {
+	userCacheDir = mockUserPath
+	setup()
+	got := userCacheDirPath()
+	if got != "/path/notation" {
+		t.Fatalf(`UserCacheDirPath() = %q, want "/path/notation"`, got)
 	}
 }
 
 func TestLocalKeyPath(t *testing.T) {
-	userConfigDir = mockGetUserConfig
-	loadUserPath()
+	userConfigDir = mockUserPath
+	setup()
+	_ = userConfigDirPath()
+	_ = userLibexecDirPath()
 	gotKeyPath, gotCertPath := LocalKeyPath("web")
 	if gotKeyPath != "localkeys/web.key" {
 		t.Fatalf(`LocalKeyPath() gotKeyPath = %q, want "localkeys/web.key"`, gotKeyPath)
@@ -35,8 +88,10 @@ func TestLocalKeyPath(t *testing.T) {
 }
 
 func TestX509TrustStoreDir(t *testing.T) {
-	userConfigDir = mockGetUserConfig
-	loadUserPath()
+	userConfigDir = mockUserPath
+	setup()
+	_ = userConfigDirPath()
+	_ = userLibexecDirPath()
 	if got := X509TrustStoreDir("ca", "web"); got != "truststore/x509/ca/web" {
 		t.Fatalf(`X509TrustStoreDir() = %q, want "truststore/x509/ca/web"`, got)
 	}

errors.go

@@ -1,12 +1,31 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation
 
 // ErrorPushSignatureFailed is used when failed to push signature to the
 // target registry.
-type ErrorPushSignatureFailed struct {
+//
+// Deprecated: Use PushSignatureFailedError instead.
+type ErrorPushSignatureFailed = PushSignatureFailedError
+
+// PushSignatureFailedError is used when failed to push signature to the
+// target registry.
+type PushSignatureFailedError struct {
 	Msg string
 }
 
-func (e ErrorPushSignatureFailed) Error() string {
+func (e PushSignatureFailedError) Error() string {
 	if e.Msg != "" {
 		return "failed to push signature to registry with error: " + e.Msg
 	}
@@ -15,11 +34,17 @@ func (e ErrorPushSignatureFailed) Error() string {
 
 // ErrorVerificationInconclusive is used when signature verification fails due
 // to a runtime error (e.g. a network error)
-type ErrorVerificationInconclusive struct {
+//
+// Deprecated: Use VerificationInconclusiveError instead.
+type ErrorVerificationInconclusive = VerificationInconclusiveError
+
+// VerificationInconclusiveError is used when signature verification fails due
+// to a runtime error (e.g. a network error)
+type VerificationInconclusiveError struct {
 	Msg string
 }
 
-func (e ErrorVerificationInconclusive) Error() string {
+func (e VerificationInconclusiveError) Error() string {
 	if e.Msg != "" {
 		return e.Msg
 	}
@@ -28,11 +53,17 @@ func (e ErrorVerificationInconclusive) Error() string {
 
 // ErrorNoApplicableTrustPolicy is used when there is no trust policy that
 // applies to the given artifact
-type ErrorNoApplicableTrustPolicy struct {
+//
+// Deprecated: Use NoApplicableTrustPolicyError instead.
+type ErrorNoApplicableTrustPolicy = NoApplicableTrustPolicyError
+
+// NoApplicableTrustPolicyError is used when there is no trust policy that
+// applies to the given artifact
+type NoApplicableTrustPolicyError struct {
 	Msg string
 }
 
-func (e ErrorNoApplicableTrustPolicy) Error() string {
+func (e NoApplicableTrustPolicyError) Error() string {
 	if e.Msg != "" {
 		return e.Msg
 	}
@@ -41,11 +72,17 @@ func (e ErrorNoApplicableTrustPolicy) Error() string {
 
 // ErrorSignatureRetrievalFailed is used when notation is unable to retrieve the
 // digital signature/s for the given artifact
-type ErrorSignatureRetrievalFailed struct {
+//
+// Deprecated: Use SignatureRetrievalFailedError instead.
+type ErrorSignatureRetrievalFailed = SignatureRetrievalFailedError
+
+// SignatureRetrievalFailedError is used when notation is unable to retrieve the
+// digital signature/s for the given artifact
+type SignatureRetrievalFailedError struct {
 	Msg string
 }
 
-func (e ErrorSignatureRetrievalFailed) Error() string {
+func (e SignatureRetrievalFailedError) Error() string {
 	if e.Msg != "" {
 		return e.Msg
 	}
@@ -54,11 +91,17 @@ func (e ErrorSignatureRetrievalFailed) Error() string {
 
 // ErrorVerificationFailed is used when it is determined that the digital
 // signature/s is not valid for the given artifact
-type ErrorVerificationFailed struct {
+//
+// Deprecated: Use VerificationFailedError instead.
+type ErrorVerificationFailed = VerificationFailedError
+
+// VerificationFailedError is used when it is determined that the digital
+// signature/s is not valid for the given artifact
+type VerificationFailedError struct {
 	Msg string
 }
 
-func (e ErrorVerificationFailed) Error() string {
+func (e VerificationFailedError) Error() string {
 	if e.Msg != "" {
 		return e.Msg
 	}
@@ -67,11 +110,17 @@ func (e ErrorVerificationFailed) Error() string {
 
 // ErrorUserMetadataVerificationFailed is used when the signature does not
 // contain the user specified metadata
-type ErrorUserMetadataVerificationFailed struct {
+//
+// Deprecated: Use UserMetadataVerificationFailedError instead.
+type ErrorUserMetadataVerificationFailed = UserMetadataVerificationFailedError
+
+// UserMetadataVerificationFailedError is used when the signature does not
+// contain the user specified metadata
+type UserMetadataVerificationFailedError struct {
 	Msg string
 }
 
-func (e ErrorUserMetadataVerificationFailed) Error() string {
+func (e UserMetadataVerificationFailedError) Error() string {
 	if e.Msg != "" {
 		return e.Msg
 	}

errors_test.go

@@ -0,0 +1,170 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package notation
+
+import "testing"
+
+func TestErrorMessages(t *testing.T) {
+	tests := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{
+			name: "ErrorPushSignatureFailed with message",
+			err:  ErrorPushSignatureFailed{Msg: "test message"},
+			want: "failed to push signature to registry with error: test message",
+		},
+		{
+			name: "ErrorPushSignatureFailed without message",
+			err:  ErrorPushSignatureFailed{},
+			want: "failed to push signature to registry",
+		},
+		{
+			name: "ErrorVerificationInconclusive with message",
+			err:  ErrorVerificationInconclusive{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "ErrorVerificationInconclusive without message",
+			err:  ErrorVerificationInconclusive{},
+			want: "signature verification was inclusive due to an unexpected error",
+		},
+		{
+			name: "ErrorNoApplicableTrustPolicy with message",
+			err:  ErrorNoApplicableTrustPolicy{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "ErrorNoApplicableTrustPolicy without message",
+			err:  ErrorNoApplicableTrustPolicy{},
+			want: "there is no applicable trust policy for the given artifact",
+		},
+		{
+			name: "ErrorSignatureRetrievalFailed with message",
+			err:  ErrorSignatureRetrievalFailed{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "ErrorSignatureRetrievalFailed without message",
+			err:  ErrorSignatureRetrievalFailed{},
+			want: "unable to retrieve the digital signature from the registry",
+		},
+		{
+			name: "ErrorVerificationFailed with message",
+			err:  ErrorVerificationFailed{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "ErrorVerificationFailed without message",
+			err:  ErrorVerificationFailed{},
+			want: "signature verification failed",
+		},
+		{
+			name: "ErrorUserMetadataVerificationFailed with message",
+			err:  ErrorUserMetadataVerificationFailed{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "ErrorUserMetadataVerificationFailed without message",
+			err:  ErrorUserMetadataVerificationFailed{},
+			want: "unable to find specified metadata in the signature",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := tt.err.Error(); got != tt.want {
+				t.Errorf("Error() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestCustomErrorPrintsCorrectMessage(t *testing.T) {
+	tests := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{
+			name: "PushSignatureFailedError with message",
+			err:  PushSignatureFailedError{Msg: "test message"},
+			want: "failed to push signature to registry with error: test message",
+		},
+		{
+			name: "PushSignatureFailedError without message",
+			err:  PushSignatureFailedError{},
+			want: "failed to push signature to registry",
+		},
+		{
+			name: "VerificationInconclusiveError with message",
+			err:  VerificationInconclusiveError{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "VerificationInconclusiveError without message",
+			err:  VerificationInconclusiveError{},
+			want: "signature verification was inclusive due to an unexpected error",
+		},
+		{
+			name: "NoApplicableTrustPolicyError with message",
+			err:  NoApplicableTrustPolicyError{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "NoApplicableTrustPolicyError without message",
+			err:  NoApplicableTrustPolicyError{},
+			want: "there is no applicable trust policy for the given artifact",
+		},
+		{
+			name: "SignatureRetrievalFailedError with message",
+			err:  SignatureRetrievalFailedError{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "SignatureRetrievalFailedError without message",
+			err:  SignatureRetrievalFailedError{},
+			want: "unable to retrieve the digital signature from the registry",
+		},
+		{
+			name: "VerificationFailedError with message",
+			err:  VerificationFailedError{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "VerificationFailedError without message",
+			err:  VerificationFailedError{},
+			want: "signature verification failed",
+		},
+		{
+			name: "UserMetadataVerificationFailedError with message",
+			err:  UserMetadataVerificationFailedError{Msg: "test message"},
+			want: "test message",
+		},
+		{
+			name: "UserMetadataVerificationFailedError without message",
+			err:  UserMetadataVerificationFailedError{},
+			want: "unable to find specified metadata in the signature",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := tt.err.Error(); got != tt.want {
+				t.Errorf("Error() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

example_localSign_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation_test
 
 import (
@@ -33,9 +46,9 @@ func Example_localSign() {
 	// exampleSigner is a notation.Signer given key and X509 certificate chain.
 	// Users should replace `exampleCertTuple.PrivateKey` with their own private
 	// key and replace `exampleCerts` with the corresponding full certificate
-	// chain, following the Notary certificate requirements:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/signature-specification.md#certificate-requirements
-	exampleSigner, err := signer.New(exampleCertTuple.PrivateKey, exampleCerts)
+	// chain, following the Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
+	exampleSigner, err := signer.NewGenericSigner(exampleCertTuple.PrivateKey, exampleCerts)
 	if err != nil {
 		panic(err) // Handle error
 	}

example_localVerify_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation_test
 
 import (
@@ -18,10 +31,10 @@ import (
 
 // examplePolicyDocument is an example of a valid trust policy document.
 // trust policy document should follow this spec:
-// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/trust-store-trust-policy.md#trust-policy
-var examplePolicyDocument = trustpolicy.Document{
+// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-policy
+var examplePolicyDocument = trustpolicy.OCIDocument{
 	Version: "1.0",
-	TrustPolicies: []trustpolicy.TrustPolicy{
+	TrustPolicies: []trustpolicy.OCITrustPolicy{
 		{
 			Name:                  "test-statement-name",
 			RegistryScopes:        []string{"example/software"},
@@ -60,9 +73,9 @@ func Example_localVerify() {
 	}
 
 	// createTrustStore creates a trust store directory for demo purpose.
-	// Users could use the default trust store from Notary and add trusted
-	// certificates into it following the trust store spec:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/trust-store-trust-policy.md#trust-store
+	// Users could use the default trust store from Notary Project and
+	// add trusted certificates into it following the trust store spec:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-store
 	if err := createTrustStore(); err != nil {
 		panic(err) // Handle error
 	}
@@ -159,8 +172,8 @@ func createTrustStore() error {
 	// generate the `exampleSignatureEnvelopePem` above.)
 	// Users should replace `exampleX509Certificate` with their own trusted
 	// certificate and add to the trust store, following the
-	// Notary certificate requirements:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/signature-specification.md#certificate-requirements
+	// Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
 	exampleX509Certificate := `-----BEGIN CERTIFICATE-----
 MIIDQDCCAiigAwIBAgIBUTANBgkqhkiG9w0BAQsFADBOMQswCQYDVQQGEwJVUzEL
 MAkGA1UECBMCV0ExEDAOBgNVBAcTB1NlYXR0bGUxDzANBgNVBAoTBk5vdGFyeTEP

example_remoteSign_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation_test
 
 import (
@@ -5,12 +18,13 @@ import (
 	"crypto/x509"
 	"fmt"
 
+	"oras.land/oras-go/v2/registry/remote"
+
 	"github.com/notaryproject/notation-core-go/signature/cose"
 	"github.com/notaryproject/notation-core-go/testhelper"
 	"github.com/notaryproject/notation-go"
 	"github.com/notaryproject/notation-go/registry"
 	"github.com/notaryproject/notation-go/signer"
-	"oras.land/oras-go/v2/registry/remote"
 )
 
 // Both COSE ("application/cose") and JWS ("application/jose+json")
@@ -31,9 +45,9 @@ func Example_remoteSign() {
 	// exampleSigner is a notation.Signer given key and X509 certificate chain.
 	// Users should replace `exampleCertTuple.PrivateKey` with their own private
 	// key and replace `exampleCerts` with the corresponding full certificate
-	// chain, following the Notary certificate requirements:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/signature-specification.md#certificate-requirements
-	exampleSigner, err := signer.New(exampleCertTuple.PrivateKey, exampleCerts)
+	// chain, following the Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
+	exampleSigner, err := signer.NewGenericSigner(exampleCertTuple.PrivateKey, exampleCerts)
 	if err != nil {
 		panic(err) // Handle error
 	}
@@ -56,13 +70,16 @@ func Example_remoteSign() {
 	// remote sign core process
 	// upon successful signing, descriptor of the sign content is returned and
 	// the generated signature is pushed into remote registry.
-	targetDesc, err := notation.Sign(context.Background(), exampleSigner, exampleRepo, exampleSignOptions)
+	targetManifestDesc, sigManifestDesc, err := notation.SignOCI(context.Background(), exampleSigner, exampleRepo, exampleSignOptions)
 	if err != nil {
 		panic(err) // Handle error
 	}
 
 	fmt.Println("Successfully signed")
-	fmt.Println("targetDesc MediaType:", targetDesc.MediaType)
-	fmt.Println("targetDesc Digest:", targetDesc.Digest)
-	fmt.Println("targetDesc Size:", targetDesc.Size)
+	fmt.Println("targetManifestDesc.MediaType:", targetManifestDesc.MediaType)
+	fmt.Println("targetManifestDesc.Digest:", targetManifestDesc.Digest)
+	fmt.Println("targetManifestDesc.Size:", targetManifestDesc.Size)
+	fmt.Println("sigManifestDesc.MediaType:", sigManifestDesc.MediaType)
+	fmt.Println("sigManifestDesc.Digest:", sigManifestDesc.Digest)
+	fmt.Println("sigManifestDesc.Size:", sigManifestDesc.Size)
 }

example_remoteVerify_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation_test
 
 import (
@@ -24,10 +37,10 @@ func Example_remoteVerify() {
 
 	// examplePolicyDocument is an example of a valid trust policy document.
 	// trust policy document should follow this spec:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/trust-store-trust-policy.md#trust-policy
-	examplePolicyDocument := trustpolicy.Document{
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-policy
+	examplePolicyDocument := trustpolicy.OCIDocument{
 		Version: "1.0",
-		TrustPolicies: []trustpolicy.TrustPolicy{
+		TrustPolicies: []trustpolicy.OCITrustPolicy{
 			{
 				Name:                  "test-statement-name",
 				RegistryScopes:        []string{"*"},
@@ -39,9 +52,9 @@ func Example_remoteVerify() {
 	}
 
 	// generateTrustStore generates a trust store directory for demo purpose.
-	// Users could use the default trust store from Notary and add trusted
-	// certificates into it following the trust store spec:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/trust-store-trust-policy.md#trust-store
+	// Users should configure their own trust store and add trusted certificates
+	// into it following the trust store spec:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-store
 	if err := generateTrustStore(); err != nil {
 		panic(err) // Handle error
 	}
@@ -88,8 +101,8 @@ func generateTrustStore() error {
 	// an example of a valid X509 self-signed certificate for demo purpose ONLY.
 	// Users should replace `exampleX509Certificate` with their own trusted
 	// certificate and add to the trust store, following the
-	// Notary certificate requirements:
-	// https://github.com/notaryproject/notaryproject/blob/v1.0.0-rc.1/specs/signature-specification.md#certificate-requirements
+	// Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
 	exampleX509Certificate := `-----BEGIN CERTIFICATE-----
 MIIDQDCCAiigAwIBAgIBUTANBgkqhkiG9w0BAQsFADBOMQswCQYDVQQGEwJVUzEL
 MAkGA1UECBMCV0ExEDAOBgNVBAcTB1NlYXR0bGUxDzANBgNVBAoTBk5vdGFyeTEP

example_signBlob_test.go

@@ -0,0 +1,88 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package notation_test
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/notaryproject/notation-core-go/signature"
+	"github.com/notaryproject/notation-core-go/signature/jws"
+	"github.com/notaryproject/notation-go"
+	"github.com/notaryproject/notation-go/signer"
+)
+
+// ExampleSignBlob demonstrates how to use [notation.SignBlob] to sign arbitrary
+// data.
+func Example_signBlob() {
+	// exampleSigner implements [notation.Signer] and [notation.BlobSigner].
+	// Given key and X509 certificate chain, it provides method to sign OCI
+	// artifacts or blobs.
+	// Users should replace `exampleCertTuple.PrivateKey` with their own private
+	// key and replace `exampleCerts` with the corresponding certificate chain,
+	// following the Notary Project certificate requirements:
+	// https://github.com/notaryproject/specifications/tree/9c81dc773508dedc5a81c02c8d805de04f65050b/specs/signature-specification.md#certificate-requirements
+	exampleSigner, err := signer.NewGenericSigner(exampleCertTuple.PrivateKey, exampleCerts)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// Both COSE ("application/cose") and JWS ("application/jose+json")
+	// signature mediaTypes are supported.
+	exampleSignatureMediaType := jws.MediaTypeEnvelope
+	exampleContentMediaType := "video/mp4"
+
+	// exampleSignOptions is an example of [notation.SignBlobOptions].
+	exampleSignOptions := notation.SignBlobOptions{
+		SignerSignOptions: notation.SignerSignOptions{
+			SignatureMediaType: exampleSignatureMediaType,
+			SigningAgent:       "example signing agent",
+		},
+		ContentMediaType: exampleContentMediaType,
+		UserMetadata:     map[string]string{"buildId": "101"},
+	}
+
+	// exampleReader reads the data that needs to be signed.
+	// This data can be in a file or in memory.
+	exampleReader := strings.NewReader("example blob")
+
+	// Upon successful signing, signature envelope and signerInfo are returned.
+	// signatureEnvelope can be used in a verification process later on.
+	signatureEnvelope, signerInfo, err := notation.SignBlob(context.Background(), exampleSigner, exampleReader, exampleSignOptions)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	fmt.Println("Successfully signed")
+
+	// a peek of the signature envelope generated
+	sigBlob, err := signature.ParseEnvelope(exampleSignatureMediaType, signatureEnvelope)
+	if err != nil {
+		panic(err) // Handle error
+	}
+	sigContent, err := sigBlob.Content()
+	if err != nil {
+		panic(err) // Handle error
+	}
+	fmt.Println("signature Payload ContentType:", sigContent.Payload.ContentType)
+	fmt.Println("signature Payload Content:", string(sigContent.Payload.Content))
+	fmt.Println("signerInfo SigningAgent:", signerInfo.UnsignedAttributes.SigningAgent)
+
+	// Output:
+	// Successfully signed
+	// signature Payload ContentType: application/vnd.cncf.notary.payload.v1+json
+	// signature Payload Content: {"targetArtifact":{"annotations":{"buildId":"101"},"digest":"sha384:b8ab24dafba5cf7e4c89c562f811cf10493d4203da982d3b1345f366ca863d9c2ed323dbd0fb7ff83a80302ceffa5a61","mediaType":"video/mp4","size":12}}
+	// signerInfo SigningAgent: example signing agent
+}

example_signWithTimestmap_test.go

@@ -0,0 +1,113 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package notation_test
+
+import (
+	"context"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+
+	"oras.land/oras-go/v2/registry/remote"
+
+	"github.com/notaryproject/notation-core-go/revocation"
+	"github.com/notaryproject/notation-core-go/revocation/purpose"
+	"github.com/notaryproject/notation-core-go/testhelper"
+	"github.com/notaryproject/notation-go"
+	"github.com/notaryproject/notation-go/registry"
+	"github.com/notaryproject/notation-go/signer"
+	"github.com/notaryproject/tspclient-go"
+)
+
+// Example_signWithTimestamp demonstrates how to use notation.Sign to sign an
+// artifact with a RFC 3161 compliant timestamp countersignature and
+// user trusted TSA root certificate
+func Example_signWithTimestamp() {
+	// exampleArtifactReference is an example of the target artifact reference
+	var exampleArtifactReference = "localhost:5000/software@sha256:60043cf45eaebc4c0867fea485a039b598f52fd09fd5b07b0b2d2f88fad9d74e"
+
+	// exampleCertTuple contains a RSA privateKey and a self-signed X509
+	// certificate generated for demo purpose ONLY.
+	exampleCertTuple := testhelper.GetRSASelfSignedSigningCertTuple("Notation Example self-signed")
+	exampleCerts := []*x509.Certificate{exampleCertTuple.Cert}
+
+	// exampleSigner is a notation.Signer given key and X509 certificate chain.
+	// Users should replace `exampleCertTuple.PrivateKey` with their own private
+	// key and replace `exampleCerts` with the corresponding full certificate
+	// chain, following the Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
+	exampleSigner, err := signer.NewGenericSigner(exampleCertTuple.PrivateKey, exampleCerts)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleRepo is an example of registry.Repository.
+	remoteRepo, err := remote.NewRepository(exampleArtifactReference)
+	if err != nil {
+		panic(err) // Handle error
+	}
+	exampleRepo := registry.NewRepository(remoteRepo)
+
+	// replace exampleRFC3161TSAServer with your trusted TSA server URL.
+	exampleRFC3161TSAServer := "<TSA server URL>"
+	httpTimestamper, err := tspclient.NewHTTPTimestamper(nil, exampleRFC3161TSAServer)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// replace exampleTSARootCertPem with your trusted TSA root cert.
+	exampleTSARootCertPem := "<TSA root cert>"
+	block, _ := pem.Decode([]byte(exampleTSARootCertPem))
+	if block == nil {
+		panic("failed to parse tsa root certificate PEM")
+	}
+	tsaRootCert, err := x509.ParseCertificate(block.Bytes)
+	if err != nil {
+		panic("failed to parse tsa root certificate: " + err.Error())
+	}
+	tsaRootCAs := x509.NewCertPool()
+	tsaRootCAs.AddCert(tsaRootCert)
+
+	// enable timestamping certificate chain revocation check
+	tsaRevocationValidator, err := revocation.NewWithOptions(revocation.Options{
+		CertChainPurpose: purpose.Timestamping,
+	})
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleSignOptions is an example of notation.SignOptions.
+	exampleSignOptions := notation.SignOptions{
+		SignerSignOptions: notation.SignerSignOptions{
+			SignatureMediaType:     exampleSignatureMediaType,
+			Timestamper:            httpTimestamper,
+			TSARootCAs:             tsaRootCAs,
+			TSARevocationValidator: tsaRevocationValidator,
+		},
+		ArtifactReference: exampleArtifactReference,
+	}
+
+	targetManifestDesc, sigManifestDesc, err := notation.SignOCI(context.Background(), exampleSigner, exampleRepo, exampleSignOptions)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	fmt.Println("Successfully signed")
+	fmt.Println("targetManifestDesc.MediaType:", targetManifestDesc.MediaType)
+	fmt.Println("targetManifestDesc.Digest:", targetManifestDesc.Digest)
+	fmt.Println("targetManifestDesc.Size:", targetManifestDesc.Size)
+	fmt.Println("sigManifestDesc.MediaType:", sigManifestDesc.MediaType)
+	fmt.Println("sigManifestDesc.Digest:", sigManifestDesc.Digest)
+	fmt.Println("sigManifestDesc.Size:", sigManifestDesc.Size)
+}

example_verifyBlob_test.go

@@ -0,0 +1,154 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package notation_test
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/notaryproject/notation-core-go/signature/jws"
+	"github.com/notaryproject/notation-go"
+	"github.com/notaryproject/notation-go/dir"
+	"github.com/notaryproject/notation-go/verifier"
+	"github.com/notaryproject/notation-go/verifier/trustpolicy"
+	"github.com/notaryproject/notation-go/verifier/truststore"
+)
+
+// exampleBlobPolicyDocument is an example of a valid blob trust policy document.
+// blob trust policy document should follow this spec:
+// https://github.com/notaryproject/specifications/tree/9c81dc773508dedc5a81c02c8d805de04f65050b/specs/trust-store-trust-policy.md#blob-trust-policy
+var exampleBlobPolicyDocument = trustpolicy.BlobDocument{
+	Version: "1.0",
+	TrustPolicies: []trustpolicy.BlobTrustPolicy{
+		{
+			Name:                  "test-statement-name",
+			SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: trustpolicy.LevelStrict.Name, Override: map[trustpolicy.ValidationType]trustpolicy.ValidationAction{trustpolicy.TypeRevocation: trustpolicy.ActionSkip}},
+			TrustStores:           []string{"ca:valid-trust-store"},
+			TrustedIdentities:     []string{"*"},
+		},
+	},
+}
+
+// ExampleVerifyBlob demonstrates how to use [notation.VerifyBlob] to verify a
+// signature of an arbitrary blob.
+func Example_verifyBlob() {
+	// Both COSE ("application/cose") and JWS ("application/jose+json")
+	// signature mediaTypes are supported.
+	exampleSignatureMediaType := jws.MediaTypeEnvelope
+
+	// exampleSignatureEnvelope is a valid signature envelope.
+	exampleSignatureEnvelope := getSignatureEnvelope()
+
+	// createTrustStoreForBlobVerify creates a trust store directory for demo purpose.
+	// Users could use the default trust store from Notary Project and add trusted
+	// certificates into it following the trust store spec:
+	// https://github.com/notaryproject/specifications/tree/9c81dc773508dedc5a81c02c8d805de04f65050b/specs/trust-store-trust-policy.md#trust-store
+	if err := createTrustStoreForBlobVerify(); err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleVerifier implements [notation.Verify] and [notation.VerifyBlob].
+	exampleVerifier, err := verifier.NewVerifierWithOptions(truststore.NewX509TrustStore(dir.ConfigFS()), verifier.VerifierOptions{
+		BlobTrustPolicy: &exampleBlobPolicyDocument,
+	})
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleReader reads the data that needs to be verified.
+	// This data can be in a file or in memory.
+	exampleReader := strings.NewReader("example blob")
+
+	// exampleVerifyOptions is an example of [notation.VerifyBlobOptions]
+	exampleVerifyOptions := notation.VerifyBlobOptions{
+		BlobVerifierVerifyOptions: notation.BlobVerifierVerifyOptions{
+			SignatureMediaType: exampleSignatureMediaType,
+			TrustPolicyName:    "test-statement-name",
+		},
+	}
+
+	// upon successful verification, the signature verification outcome is
+	// returned.
+	_, outcome, err := notation.VerifyBlob(context.Background(), exampleVerifier, exampleReader, []byte(exampleSignatureEnvelope), exampleVerifyOptions)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	fmt.Println("Successfully verified")
+
+	// a peek of the payload inside the signature envelope
+	fmt.Println("payload ContentType:", outcome.EnvelopeContent.Payload.ContentType)
+
+	// Note, upon successful verification, payload.TargetArtifact from the
+	// signature envelope matches exactly with our exampleTargetDescriptor.
+	// (This check has been done for the user inside verifier.Verify.)
+	fmt.Println("payload Content:", string(outcome.EnvelopeContent.Payload.Content))
+
+	// Output:
+	// Successfully verified
+	// payload ContentType: application/vnd.cncf.notary.payload.v1+json
+	// payload Content: {"targetArtifact":{"digest":"sha384:b8ab24dafba5cf7e4c89c562f811cf10493d4203da982d3b1345f366ca863d9c2ed323dbd0fb7ff83a80302ceffa5a61","mediaType":"video/mp4","size":12}}
+}
+
+func createTrustStoreForBlobVerify() error {
+	// changing the path of the trust store for demo purpose.
+	// Users could keep the default value, i.e. os.UserConfigDir.
+	dir.UserConfigDir = "tmp"
+
+	// an example of a valid X509 self-signed certificate for demo purpose ONLY.
+	// (This self-signed cert is paired with the private key used to
+	// generate the `exampleSignatureEnvelopePem` above.)
+	// Users should replace `exampleX509Certificate` with their own trusted
+	// certificate and add to the trust store, following the
+	// Notary Project certificate requirements:
+	// https://github.com/notaryproject/specifications/tree/9c81dc773508dedc5a81c02c8d805de04f65050b/specs/signature-specification.md#certificate-requirements
+	exampleX509Certificate := `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+	// Adding the certificate into the trust store.
+	if err := os.MkdirAll("tmp/truststore/x509/ca/valid-trust-store", 0700); err != nil {
+		return err
+	}
+	return os.WriteFile("tmp/truststore/x509/ca/valid-trust-store/NotationBlobExample.pem", []byte(exampleX509Certificate), 0600)
+}
+
+func getSignatureEnvelope() string {
+	return `{"payload":"eyJ0YXJnZXRBcnRpZmFjdCI6eyJkaWdlc3QiOiJzaGEzODQ6YjhhYjI0ZGFmYmE1Y2Y3ZTRjODljNTYyZjgxMWNmMTA0OTNkNDIwM2RhOTgyZDNiMTM0NWYzNjZjYTg2M2Q5YzJlZDMyM2RiZDBmYjdmZjgzYTgwMzAyY2VmZmE1YTYxIiwibWVkaWFUeXBlIjoidmlkZW8vbXA0Iiwic2l6ZSI6MTJ9fQ","protected":"eyJhbGciOiJQUzM4NCIsImNyaXQiOlsiaW8uY25jZi5ub3Rhcnkuc2lnbmluZ1NjaGVtZSJdLCJjdHkiOiJhcHBsaWNhdGlvbi92bmQuY25jZi5ub3RhcnkucGF5bG9hZC52MStqc29uIiwiaW8uY25jZi5ub3Rhcnkuc2lnbmluZ1NjaGVtZSI6Im5vdGFyeS54NTA5IiwiaW8uY25jZi5ub3Rhcnkuc2lnbmluZ1RpbWUiOiIyMDI0LTA0LTA0VDE0OjIwOjIxLTA3OjAwIn0","header":{"x5c":["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"],"io.cncf.notary.signingAgent":"example signing agent"},"signature":"liOjdgQ9BKuQTZGXRh3o6P8AMUIq_MKQReEcqA5h8M4RYs3DV_wXfaLCr2x_NRcwjTZsoO1_J77hmzkkk4L0IuFP8Qw0KKtmc83G0yFi4yYV5fwzrIbnhC2GRLuqLPnK-C4qYmv52ld3ebvo7XWwRHu30-VXePmTRFp6iG-eSAgkNgwhxSZ0ZmTFLG3ceNiX2bxpLHlXdPwA3aFKbd6nKrzo4CZ1ZyLNmAIaoA5-kmc0Hyt45trpxaaiWusI_pcTLw71YCqEAs32tEq3q6hRAgAZZN-Qvm9GyNp9EuaPiKjMbJFqtjome5ITxyNd-5t09dDCUgSe3t-iqv2Blm4E080AP1TYwUKLYklGniUP1dAtOau5G2juZLpl7tr4LQ99mycflnAmV7e79eEWXffvy5EAl77dW4_vM7lEemm08m2wddGuDOWXYb1j1r2_a5Xb92umHq6ZMhAp200A0pUkm9640x8z5jdudi_7KeezdqUK7ZMmSxHohiylyKD_20Cy"}`
+}

example_verifyWithTimestamp_test.go

@@ -0,0 +1,192 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package notation_test
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	_ "github.com/notaryproject/notation-core-go/signature/cose"
+	_ "github.com/notaryproject/notation-core-go/signature/jws"
+	"github.com/notaryproject/notation-go"
+	"github.com/notaryproject/notation-go/dir"
+	"github.com/notaryproject/notation-go/registry"
+	"github.com/notaryproject/notation-go/verifier"
+	"github.com/notaryproject/notation-go/verifier/trustpolicy"
+	"github.com/notaryproject/notation-go/verifier/truststore"
+	"oras.land/oras-go/v2/registry/remote"
+)
+
+// Example_verifyWithTimestamp demonstrates how to use notation.Verify to verify
+// signature of an artifact including RFC 3161 compliant timestamp countersignature
+func Example_verifyWithTimestamp() {
+	// exampleArtifactReference is an example of the target artifact reference
+	exampleArtifactReference := "localhost:5000/software@sha256:60043cf45eaebc4c0867fea485a039b598f52fd09fd5b07b0b2d2f88fad9d74e"
+
+	// examplePolicyDocument is an example of a valid trust policy document with
+	// timestamping configurations.
+	// trust policy document should follow this spec:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-policy
+	examplePolicyDocument := trustpolicy.OCIDocument{
+		Version: "1.0",
+		TrustPolicies: []trustpolicy.OCITrustPolicy{
+			{
+				Name:           "test-statement-name",
+				RegistryScopes: []string{"*"},
+				SignatureVerification: trustpolicy.SignatureVerification{
+					VerificationLevel: trustpolicy.LevelStrict.Name,
+
+					// verify timestamp countersignature only if the signing
+					// certificate chain has expired.
+					// Default: trustpolicy.OptionAlways
+					VerifyTimestamp: trustpolicy.OptionAfterCertExpiry,
+				},
+
+				// `tsa` trust store type MUST be configured to enable
+				// timestamp verification
+				TrustStores: []string{"ca:valid-trust-store", "tsa:valid-tsa"},
+
+				// TrustedIdentities only contains trusted identities of `ca`
+				// and `signingAuthority`
+				TrustedIdentities: []string{"*"},
+			},
+		},
+	}
+
+	// generateTrustStoreWithTimestamp generates a trust store directory for demo purpose.
+	// Users should configure their own trust store and add trusted certificates
+	// into it following the trust store spec:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/trust-store-trust-policy.md#trust-store
+	if err := generateTrustStoreWithTimestamp(); err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleVerifier is an example of notation.Verifier given
+	// trust policy document and X509 trust store.
+	exampleVerifier, err := verifier.New(&examplePolicyDocument, truststore.NewX509TrustStore(dir.ConfigFS()), nil)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	// exampleRepo is an example of registry.Repository.
+	remoteRepo, err := remote.NewRepository(exampleArtifactReference)
+	if err != nil {
+		panic(err) // Handle error
+	}
+	exampleRepo := registry.NewRepository(remoteRepo)
+
+	// exampleVerifyOptions is an example of notation.VerifyOptions.
+	exampleVerifyOptions := notation.VerifyOptions{
+		ArtifactReference:    exampleArtifactReference,
+		MaxSignatureAttempts: 50,
+	}
+
+	// remote verify core process
+	// upon successful verification, the target manifest descriptor
+	// and signature verification outcome are returned.
+	targetDesc, _, err := notation.Verify(context.Background(), exampleVerifier, exampleRepo, exampleVerifyOptions)
+	if err != nil {
+		panic(err) // Handle error
+	}
+
+	fmt.Println("Successfully verified")
+	fmt.Println("targetDesc MediaType:", targetDesc.MediaType)
+	fmt.Println("targetDesc Digest:", targetDesc.Digest)
+	fmt.Println("targetDesc Size:", targetDesc.Size)
+}
+
+func generateTrustStoreWithTimestamp() error {
+	// changing the path of the trust store for demo purpose.
+	// Users could keep the default value, i.e. os.UserConfigDir.
+	dir.UserConfigDir = "tmp"
+
+	// an example of a valid X509 self-signed certificate for demo purpose ONLY.
+	// Users should replace `exampleX509Certificate` with their own trusted
+	// certificate and add to the trust store, following the
+	// Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
+	exampleX509Certificate := `-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----`
+
+	// Adding the certificate into the trust store.
+	if err := os.MkdirAll("tmp/truststore/x509/ca/valid-trust-store", 0700); err != nil {
+		return err
+	}
+	if err := os.WriteFile("tmp/truststore/x509/ca/valid-trust-store/NotationExample.pem", []byte(exampleX509Certificate), 0600); err != nil {
+		return err
+	}
+
+	// an example of a valid TSA root certificate for demo purpose ONLY.
+	// Users should replace `exampleTSARootCertificate` with their own trusted
+	// TSA root certificate and add to the trust store, following the
+	// Notary Project certificate requirements:
+	// https://github.com/notaryproject/notaryproject/blob/v1.0.0/specs/signature-specification.md#certificate-requirements
+	exampleTSARootCertificate := `-----BEGIN CERTIFICATE-----
+		MIIFkDCCA3igAwIBAgIQBZsbV56OITLiOQe9p3d1XDANBgkqhkiG9w0BAQwFADBi
+		MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
+		d3cuZGlnaWNlcnQuY29tMSEwHwYDVQQDExhEaWdpQ2VydCBUcnVzdGVkIFJvb3Qg
+		RzQwHhcNMTMwODAxMTIwMDAwWhcNMzgwMTE1MTIwMDAwWjBiMQswCQYDVQQGEwJV
+		UzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3d3cuZGlnaWNlcnQu
+		Y29tMSEwHwYDVQQDExhEaWdpQ2VydCBUcnVzdGVkIFJvb3QgRzQwggIiMA0GCSqG
+		SIb3DQEBAQUAA4ICDwAwggIKAoICAQC/5pBzaN675F1KPDAiMGkz7MKnJS7JIT3y
+		ithZwuEppz1Yq3aaza57G4QNxDAf8xukOBbrVsaXbR2rsnnyyhHS5F/WBTxSD1If
+		xp4VpX6+n6lXFllVcq9ok3DCsrp1mWpzMpTREEQQLt+C8weE5nQ7bXHiLQwb7iDV
+		ySAdYyktzuxeTsiT+CFhmzTrBcZe7FsavOvJz82sNEBfsXpm7nfISKhmV1efVFiO
+		DCu3T6cw2Vbuyntd463JT17lNecxy9qTXtyOj4DatpGYQJB5w3jHtrHEtWoYOAMQ
+		jdjUN6QuBX2I9YI+EJFwq1WCQTLX2wRzKm6RAXwhTNS8rhsDdV14Ztk6MUSaM0C/
+		CNdaSaTC5qmgZ92kJ7yhTzm1EVgX9yRcRo9k98FpiHaYdj1ZXUJ2h4mXaXpI8OCi
+		EhtmmnTK3kse5w5jrubU75KSOp493ADkRSWJtppEGSt+wJS00mFt6zPZxd9LBADM
+		fRyVw4/3IbKyEbe7f/LVjHAsQWCqsWMYRJUadmJ+9oCw++hkpjPRiQfhvbfmQ6QY
+		uKZ3AeEPlAwhHbJUKSWJbOUOUlFHdL4mrLZBdd56rF+NP8m800ERElvlEFDrMcXK
+		chYiCd98THU/Y+whX8QgUWtvsauGi0/C1kVfnSD8oR7FwI+isX4KJpn15GkvmB0t
+		9dmpsh3lGwIDAQABo0IwQDAPBgNVHRMBAf8EBTADAQH/MA4GA1UdDwEB/wQEAwIB
+		hjAdBgNVHQ4EFgQU7NfjgtJxXWRM3y5nP+e6mK4cD08wDQYJKoZIhvcNAQEMBQAD
+		ggIBALth2X2pbL4XxJEbw6GiAI3jZGgPVs93rnD5/ZpKmbnJeFwMDF/k5hQpVgs2
+		SV1EY+CtnJYYZhsjDT156W1r1lT40jzBQ0CuHVD1UvyQO7uYmWlrx8GnqGikJ9yd
+		+SeuMIW59mdNOj6PWTkiU0TryF0Dyu1Qen1iIQqAyHNm0aAFYF/opbSnr6j3bTWc
+		fFqK1qI4mfN4i/RN0iAL3gTujJtHgXINwBQy7zBZLq7gcfJW5GqXb5JQbZaNaHqa
+		sjYUegbyJLkJEVDXCLG4iXqEI2FCKeWjzaIgQdfRnGTZ6iahixTXTBmyUEFxPT9N
+		cCOGDErcgdLMMpSEDQgJlxxPwO5rIHQw0uA5NBCFIRUBCOhVMt5xSdkoF1BN5r5N
+		0XWs0Mr7QbhDparTwwVETyw2m+L64kW4I1NsBm9nVX9GtUw/bihaeSbSpKhil9Ie
+		4u1Ki7wb/UdKDd9nZn6yW0HQO+T0O/QEY+nvwlQAUaCKKsnOeMzV6ocEGLPOr0mI
+		r/OSmbaz5mEP0oUA51Aa5BuVnRmhuZyxm7EAHu/QD09CbMkKvO5D+jpxpchNJqU1
+		/YldvIViHTLSoCtU7ZpXwdv6EM8Zt4tKG48BtieVU+i2iW1bvGjUI+iLUaJW+fCm
+		gKDWHrO8Dw9TdSmq6hN35N6MgSGtBxBHEa2HPQfRdbzP82Z+
+		-----END CERTIFICATE-----`
+
+	// Adding the tsa root certificate into the trust store.
+	if err := os.MkdirAll("tmp/truststore/x509/tsa/valid-tsa", 0700); err != nil {
+		return err
+	}
+	return os.WriteFile("tmp/truststore/x509/tsa/valid-tsa/NotationTSAExample.pem", []byte(exampleTSARootCertificate), 0600)
+}

go.mod

@@ -1,23 +1,26 @@
 module github.com/notaryproject/notation-go
 
-go 1.19
+go 1.23.0
 
 require (
-	github.com/go-ldap/ldap/v3 v3.4.4
-	github.com/notaryproject/notation-core-go v1.0.0-rc.3
+	github.com/go-ldap/ldap/v3 v3.4.11
+	github.com/notaryproject/notation-core-go v1.3.0
+	github.com/notaryproject/notation-plugin-framework-go v1.0.0
+	github.com/notaryproject/tspclient-go v1.0.0
 	github.com/opencontainers/go-digest v1.0.0
-	github.com/opencontainers/image-spec v1.1.0-rc.3
-	github.com/veraison/go-cose v1.0.0
-	golang.org/x/crypto v0.9.0
-	golang.org/x/mod v0.10.0
-	oras.land/oras-go/v2 v2.1.0
+	github.com/opencontainers/image-spec v1.1.1
+	github.com/veraison/go-cose v1.3.0
+	golang.org/x/crypto v0.39.0
+	golang.org/x/mod v0.25.0
+	oras.land/oras-go/v2 v2.6.0
 )
 
 require (
 	github.com/Azure/go-ntlmssp v0.0.0-20221128193559-754e69321358 // indirect
-	github.com/fxamacker/cbor/v2 v2.4.0 // indirect
-	github.com/go-asn1-ber/asn1-ber v1.5.4 // indirect
-	github.com/golang-jwt/jwt/v4 v4.5.0 // indirect
+	github.com/fxamacker/cbor/v2 v2.8.0 // indirect
+	github.com/go-asn1-ber/asn1-ber v1.5.8-0.20250403174932-29230038a667 // indirect
+	github.com/golang-jwt/jwt/v4 v4.5.2 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/x448/float16 v0.8.4 // indirect
-	golang.org/x/sync v0.1.0 // indirect
+	golang.org/x/sync v0.14.0 // indirect
 )

go.sum

@@ -1,47 +1,60 @@
-github.com/Azure/go-ntlmssp v0.0.0-20220621081337-cb9428e4ac1e/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
 github.com/Azure/go-ntlmssp v0.0.0-20221128193559-754e69321358 h1:mFRzDkZVAjdal+s7s0MwaRv9igoPqLRdzOLzw/8Xvq8=
 github.com/Azure/go-ntlmssp v0.0.0-20221128193559-754e69321358/go.mod h1:chxPXzSsl7ZWRAuOIE23GDNzjWuZquvFlgA8xmpunjU=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/alexbrainman/sspi v0.0.0-20231016080023-1a75b4708caa h1:LHTHcTQiSGT7VVbI0o4wBRNQIgn917usHWOd6VAffYI=
+github.com/alexbrainman/sspi v0.0.0-20231016080023-1a75b4708caa/go.mod h1:cEWa1LVoE5KvSD9ONXsZrj0z6KqySlCCNKHlLzbqAt4=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
-github.com/fxamacker/cbor/v2 v2.4.0 h1:ri0ArlOR+5XunOP8CRUowT0pSJOwhW098ZCUyskZD88=
-github.com/fxamacker/cbor/v2 v2.4.0/go.mod h1:TA1xS00nchWmaBnEIxPSE5oHLuJBAVvqrtAnWBwBCVo=
-github.com/go-asn1-ber/asn1-ber v1.5.4 h1:vXT6d/FNDiELJnLb6hGNa309LMsrCoYFvpwHDF0+Y1A=
-github.com/go-asn1-ber/asn1-ber v1.5.4/go.mod h1:hEBeB/ic+5LoWskz+yKT7vGhhPYkProFKoKdwZRWMe0=
-github.com/go-ldap/ldap/v3 v3.4.4 h1:qPjipEpt+qDa6SI/h1fzuGWoRUY+qqQ9sOZq67/PYUs=
-github.com/go-ldap/ldap/v3 v3.4.4/go.mod h1:fe1MsuN5eJJ1FeLT/LEBVdWfNWKh459R7aXgXtJC+aI=
-github.com/golang-jwt/jwt/v4 v4.5.0 h1:7cYmW1XlMY7h7ii7UhUyChSgS5wUJEnm9uZVTGqOWzg=
-github.com/golang-jwt/jwt/v4 v4.5.0/go.mod h1:m21LjoU+eqJr34lmDMbreY2eSTRJ1cv77w39/MY0Ch0=
-github.com/notaryproject/notation-core-go v1.0.0-rc.3 h1:ukRBOwctPF0bWLFs+ThDHwgj+L3+AHdyaOqmziLp8w0=
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 github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
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internal/container/set.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package set
 
 // Set is a map as a set data structure.

internal/envelope/envelope.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package envelope
 
 import (

internal/envelope/envelope_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package envelope
 
 import (

internal/file/file.go

@@ -1,8 +1,153 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package file
 
-import "regexp"
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+const (
+	// tempFileNamePrefix is the prefix of the temporary file
+	tempFileNamePrefix = "notation-*"
+)
+
+// ErrNotRegularFile is returned when the file is not an regular file.
+var ErrNotRegularFile = errors.New("not regular file")
+
+// ErrNotDirectory is returned when the path is not a directory.
+var ErrNotDirectory = errors.New("not directory")
 
 // IsValidFileName checks if a file name is cross-platform compatible
 func IsValidFileName(fileName string) bool {
 	return regexp.MustCompile(`^[a-zA-Z0-9_.-]+$`).MatchString(fileName)
 }
+
+// CopyToDir copies the src file to dst dir. All parent directories are created
+// with permissions 0755.
+//
+// Source file's read and execute permissions are preserved for everyone.
+// Write permission is preserved for owner. Group and others cannot write.
+// Existing file will be overwritten.
+func CopyToDir(src, dst string) error {
+	sourceFileInfo, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	if !sourceFileInfo.Mode().IsRegular() {
+		return ErrNotRegularFile
+	}
+	source, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer source.Close()
+	if err := os.MkdirAll(dst, 0755); err != nil {
+		return err
+	}
+	dstFile := filepath.Join(dst, filepath.Base(src))
+	destination, err := os.Create(dstFile)
+	if err != nil {
+		return err
+	}
+	defer destination.Close()
+	err = destination.Chmod(sourceFileInfo.Mode() & os.FileMode(0755))
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(destination, source)
+	return err
+}
+
+// CopyDirToDir copies contents in src dir to dst dir. Only regular files are
+// copied. Existing files will be overwritten.
+func CopyDirToDir(src, dst string) error {
+	fi, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	if !fi.Mode().IsDir() {
+		return ErrNotDirectory
+	}
+	return filepath.WalkDir(src, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		// skip sub-directories
+		if d.IsDir() && d.Name() != filepath.Base(path) {
+			return fs.SkipDir
+		}
+		info, err := d.Info()
+		if err != nil {
+			return err
+		}
+		// only copy regular files
+		if info.Mode().IsRegular() {
+			return CopyToDir(path, dst)
+		}
+		return nil
+	})
+}
+
+// TrimFileExtension returns the file name without extension.
+//
+// For example,
+//
+// when input is xyz.exe, output is xyz
+//
+// when input is xyz.tar.gz, output is xyz.tar
+func TrimFileExtension(fileName string) string {
+	return strings.TrimSuffix(fileName, filepath.Ext(fileName))
+}
+
+// WriteFile writes content to a temporary file and moves it to path.
+// If path already exists and is a file, WriteFile overwrites it.
+//
+// Parameters:
+//   - tempDir is the directory to create the temporary file. It should be
+//     in the same mount point as path. If tempDir is empty, the default
+//     directory for temporary files is used.
+//   - path is the destination file path.
+//   - content is the content to write.
+func WriteFile(tempDir, path string, content []byte) (writeErr error) {
+	tempFile, err := os.CreateTemp(tempDir, tempFileNamePrefix)
+	if err != nil {
+		return fmt.Errorf("failed to create temp file: %w", err)
+	}
+	defer func() {
+		// remove the temp file in case of error
+		if writeErr != nil {
+			tempFile.Close()
+			os.Remove(tempFile.Name())
+		}
+	}()
+
+	if _, err := tempFile.Write(content); err != nil {
+		return fmt.Errorf("failed to write content to temp file: %w", err)
+	}
+
+	// close before moving
+	if err := tempFile.Close(); err != nil {
+		return fmt.Errorf("failed to close temp file: %w", err)
+	}
+
+	// rename is atomic on UNIX-like platforms
+	return os.Rename(tempFile.Name(), path)
+}

internal/file/file_test.go

@@ -0,0 +1,214 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package file
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestCopyToDir(t *testing.T) {
+	t.Run("copy file", func(t *testing.T) {
+		tempDir := t.TempDir()
+		data := []byte("data")
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+
+		destDir := filepath.Join(tempDir, "b")
+		if err := CopyToDir(filename, destDir); err != nil {
+			t.Fatal(err)
+		}
+	})
+
+	t.Run("source directory permission error", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		tempDir := t.TempDir()
+		destDir := t.TempDir()
+		data := []byte("data")
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+
+		if err := os.Chmod(tempDir, 0000); err != nil {
+			t.Fatal(err)
+		}
+		defer os.Chmod(tempDir, 0700)
+
+		if err := CopyToDir(filename, destDir); err == nil {
+			t.Fatal("should have error")
+		}
+	})
+
+	t.Run("not a regular file", func(t *testing.T) {
+		tempDir := t.TempDir()
+		destDir := t.TempDir()
+		if err := CopyToDir(tempDir, destDir); err == nil {
+			t.Fatal("should have error")
+		}
+	})
+
+	t.Run("source file permission error", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		tempDir := t.TempDir()
+		destDir := t.TempDir()
+		data := []byte("data")
+		// prepare file
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+		// forbid reading
+		if err := os.Chmod(filename, 0000); err != nil {
+			t.Fatal(err)
+		}
+		defer os.Chmod(filename, 0600)
+		if err := CopyToDir(filename, destDir); err == nil {
+			t.Fatal("should have error")
+		}
+	})
+
+	t.Run("dest directory permission error", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		tempDir := t.TempDir()
+		destTempDir := t.TempDir()
+		data := []byte("data")
+		// prepare file
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+		// forbid dest directory operation
+		if err := os.Chmod(destTempDir, 0000); err != nil {
+			t.Fatal(err)
+		}
+		defer os.Chmod(destTempDir, 0700)
+		if err := CopyToDir(filename, filepath.Join(destTempDir, "a")); err == nil {
+			t.Fatal("should have error")
+		}
+	})
+
+	t.Run("dest directory permission error 2", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		tempDir := t.TempDir()
+		destTempDir := t.TempDir()
+		data := []byte("data")
+		// prepare file
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+		// forbid writing to destTempDir
+		if err := os.Chmod(destTempDir, 0000); err != nil {
+			t.Fatal(err)
+		}
+		defer os.Chmod(destTempDir, 0700)
+		if err := CopyToDir(filename, destTempDir); err == nil {
+			t.Fatal("should have error")
+		}
+	})
+
+	t.Run("copy file and check content", func(t *testing.T) {
+		tempDir := t.TempDir()
+		data := []byte("data")
+		filename := filepath.Join(tempDir, "a", "file.txt")
+		if err := os.MkdirAll(filepath.Dir(filename), 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := WriteFile(tempDir, filename, data); err != nil {
+			t.Fatal(err)
+		}
+
+		destDir := filepath.Join(tempDir, "b")
+		if err := CopyToDir(filename, destDir); err != nil {
+			t.Fatal(err)
+		}
+		validFileContent(t, filepath.Join(destDir, "file.txt"), data)
+	})
+}
+
+func TestFileNameWithoutExtension(t *testing.T) {
+	input := "testfile.tar.gz"
+	expectedOutput := "testfile.tar"
+	actualOutput := TrimFileExtension(input)
+	if actualOutput != expectedOutput {
+		t.Errorf("expected '%s', but got '%s'", expectedOutput, actualOutput)
+	}
+}
+
+func TestWriteFile(t *testing.T) {
+	tempDir := t.TempDir()
+	content := []byte("test WriteFile")
+
+	t.Run("permission denied", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+		err := os.Chmod(tempDir, 0)
+		if err != nil {
+			t.Fatal(err)
+		}
+		err = WriteFile(tempDir, filepath.Join(tempDir, "testFile"), content)
+		if err == nil || !strings.Contains(err.Error(), "permission denied") {
+			t.Fatalf("expected permission denied error, but got %s", err)
+		}
+		err = os.Chmod(tempDir, 0700)
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
+}
+
+func validFileContent(t *testing.T, filename string, content []byte) {
+	b, err := os.ReadFile(filename)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(content, b) {
+		t.Fatal("file content is not correct")
+	}
+}

internal/io/limitedwriter.go

@@ -0,0 +1,53 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package io provides a LimitWriter that writes to an underlying writer up to
+// a limit.
+
+package io
+
+import (
+	"errors"
+	"io"
+)
+
+// ErrLimitExceeded is returned when the write limit is exceeded.
+var ErrLimitExceeded = errors.New("write limit exceeded")
+
+// LimitedWriter is a writer that writes to an underlying writer up to a limit.
+type LimitedWriter struct {
+	W io.Writer // underlying writer
+	N int64     // remaining bytes
+}
+
+// LimitWriter returns a new LimitWriter that writes to w.
+//
+// parameters:
+// w: the writer to write to
+// limit: the maximum number of bytes to write
+func LimitWriter(w io.Writer, limit int64) *LimitedWriter {
+	return &LimitedWriter{W: w, N: limit}
+}
+
+// Write writes p to the underlying writer up to the limit.
+func (l *LimitedWriter) Write(p []byte) (int, error) {
+	if l.N <= 0 {
+		return 0, ErrLimitExceeded
+	}
+	if int64(len(p)) > l.N {
+		p = p[:l.N]
+	}
+	n, err := l.W.Write(p)
+	l.N -= int64(n)
+	return n, err
+}

internal/io/limitedwriter_test.go

@@ -0,0 +1,67 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package io
+
+import (
+	"bytes"
+	"errors"
+	"testing"
+)
+
+func TestLimitWriter(t *testing.T) {
+	limit := int64(10)
+
+	tests := []struct {
+		input    string
+		expected string
+		written  int
+	}{
+		{"hello", "hello", 5},
+		{" world", " world", 6},
+		{"!", "!", 1},
+		{"1234567891011", "1234567891", 10},
+	}
+
+	for _, tt := range tests {
+		var buf bytes.Buffer
+		lw := LimitWriter(&buf, limit)
+		n, err := lw.Write([]byte(tt.input))
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if n != tt.written {
+			t.Errorf("expected %d bytes written, got %d", tt.written, n)
+		}
+		if buf.String() != tt.expected {
+			t.Errorf("expected buffer %q, got %q", tt.expected, buf.String())
+		}
+	}
+}
+
+func TestLimitWriterFailed(t *testing.T) {
+	limit := int64(10)
+	longString := "1234567891011"
+
+	var buf bytes.Buffer
+	lw := LimitWriter(&buf, limit)
+	_, err := lw.Write([]byte(longString))
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	_, err = lw.Write([]byte(longString))
+	expectedErr := errors.New("write limit exceeded")
+	if err.Error() != expectedErr.Error() {
+		t.Errorf("expected error %v, got %v", expectedErr, err)
+	}
+}

internal/mock/mockfs/fs.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package mockfs
 
 import (

internal/mock/mocks.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package mock
 
 import (
@@ -5,8 +18,7 @@ import (
 	_ "embed"
 
 	"github.com/notaryproject/notation-core-go/signature"
-	"github.com/notaryproject/notation-go/plugin"
-	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
@@ -65,6 +77,7 @@ var MockCaCompatiblePluginVerSigEnv_1_0_0 []byte
 var (
 	SampleArtifactUri = "registry.acme-rockets.io/software/net-monitor@sha256:60043cf45eaebc4c0867fea485a039b598f52fd09fd5b07b0b2d2f88fad9d74e"
 	SampleDigest      = digest.Digest("sha256:60043cf45eaebc4c0867fea485a039b598f52fd09fd5b07b0b2d2f88fad9d74e")
+	ZeroDigest        = digest.Digest("sha256:0000000000000000000000000000000000000000000000000000000000000000")
 	Annotations       = map[string]string{"key": "value"}
 	ImageDescriptor   = ocispec.Descriptor{
 		MediaType:   "application/vnd.docker.distribution.manifest.v2+json",
@@ -110,6 +123,9 @@ type Repository struct {
 	ListSignaturesError        error
 	FetchSignatureBlobResponse []byte
 	FetchSignatureBlobError    error
+	MissMatchDigest            bool
+	ExceededNumOfSignatures    bool
+	PushSignatureError         error
 }
 
 func NewRepository() Repository {
@@ -121,10 +137,21 @@ func NewRepository() Repository {
 }
 
 func (t Repository) Resolve(ctx context.Context, reference string) (ocispec.Descriptor, error) {
+	if t.MissMatchDigest {
+		return ocispec.Descriptor{
+			MediaType:   "application/vnd.docker.distribution.manifest.v2+json",
+			Digest:      ZeroDigest,
+			Size:        528,
+			Annotations: Annotations,
+		}, nil
+	}
 	return t.ResolveResponse, t.ResolveError
 }
 
 func (t Repository) ListSignatures(ctx context.Context, desc ocispec.Descriptor, fn func(signatureManifests []ocispec.Descriptor) error) error {
+	if t.ExceededNumOfSignatures {
+		t.ListSignaturesResponse = []ocispec.Descriptor{SigManfiestDescriptor, SigManfiestDescriptor}
+	}
 	err := fn(t.ListSignaturesResponse)
 	if err != nil {
 		return err
@@ -137,40 +164,44 @@ func (t Repository) FetchSignatureBlob(ctx context.Context, desc ocispec.Descrip
 }
 
 func (t Repository) PushSignature(ctx context.Context, mediaType string, blob []byte, subject ocispec.Descriptor, annotations map[string]string) (blobDesc, manifestDesc ocispec.Descriptor, err error) {
+	if t.PushSignatureError != nil {
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, t.PushSignatureError
+	}
+
 	return ocispec.Descriptor{}, ocispec.Descriptor{}, nil
 }
 
 type PluginMock struct {
-	Metadata        proto.GetMetadataResponse
+	Metadata        plugin.GetMetadataResponse
 	ExecuteResponse interface{}
 	ExecuteError    error
 }
 
-func (p *PluginMock) GetMetadata(ctx context.Context, req *proto.GetMetadataRequest) (*proto.GetMetadataResponse, error) {
+func (p *PluginMock) GetMetadata(ctx context.Context, req *plugin.GetMetadataRequest) (*plugin.GetMetadataResponse, error) {
 	return &p.Metadata, nil
 }
 
-func (p *PluginMock) VerifySignature(ctx context.Context, req *proto.VerifySignatureRequest) (*proto.VerifySignatureResponse, error) {
-	if resp, ok := p.ExecuteResponse.(*proto.VerifySignatureResponse); ok {
+func (p *PluginMock) VerifySignature(ctx context.Context, req *plugin.VerifySignatureRequest) (*plugin.VerifySignatureResponse, error) {
+	if resp, ok := p.ExecuteResponse.(*plugin.VerifySignatureResponse); ok {
 		return resp, nil
 	}
 	return nil, p.ExecuteError
 }
 
-func (p *PluginMock) DescribeKey(ctx context.Context, req *proto.DescribeKeyRequest) (*proto.DescribeKeyResponse, error) {
+func (p *PluginMock) DescribeKey(ctx context.Context, req *plugin.DescribeKeyRequest) (*plugin.DescribeKeyResponse, error) {
 	panic("not implemented") // TODO: Implement
 }
 
-func (p *PluginMock) GenerateSignature(ctx context.Context, req *proto.GenerateSignatureRequest) (*proto.GenerateSignatureResponse, error) {
+func (p *PluginMock) GenerateSignature(ctx context.Context, req *plugin.GenerateSignatureRequest) (*plugin.GenerateSignatureResponse, error) {
 	panic("not implemented") // TODO: Implement
 }
 
-func (p *PluginMock) GenerateEnvelope(ctx context.Context, req *proto.GenerateEnvelopeRequest) (*proto.GenerateEnvelopeResponse, error) {
+func (p *PluginMock) GenerateEnvelope(ctx context.Context, req *plugin.GenerateEnvelopeRequest) (*plugin.GenerateEnvelopeResponse, error) {
 	panic("not implemented") // TODO: Implement
 }
 
 type PluginManager struct {
-	PluginCapabilities          []proto.Capability
+	PluginCapabilities          []plugin.Capability
 	GetPluginError              error
 	PluginRunnerLoadError       error
 	PluginRunnerExecuteResponse interface{}
@@ -179,7 +210,7 @@ type PluginManager struct {
 
 func (pm PluginManager) Get(ctx context.Context, name string) (plugin.Plugin, error) {
 	return &PluginMock{
-		Metadata: proto.GetMetadataResponse{
+		Metadata: plugin.GetMetadataResponse{
 			Name:                      "plugin-name",
 			Description:               "for mocking in unit tests",
 			Version:                   "1.0.0",

internal/mock/ocilayout/ocilayout.go

@@ -0,0 +1,47 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ocilayout
+
+import (
+	"context"
+	"os"
+
+	"oras.land/oras-go/v2"
+	"oras.land/oras-go/v2/content/oci"
+)
+
+// Copy creates a temporary OCI layout for testing
+// and returns the path to the layout.
+func Copy(sourcePath, destPath, tag string) error {
+	ctx := context.Background()
+
+	srcStore, err := oci.NewFromFS(ctx, os.DirFS(sourcePath))
+	if err != nil {
+		return err
+	}
+
+	// create a dest store for store the generated oci layout.
+	destStore, err := oci.New(destPath)
+	if err != nil {
+		return err
+	}
+
+	// copy data
+	_, err = oras.ExtendedCopy(ctx, srcStore, tag, destStore, "", oras.DefaultExtendedCopyOptions)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

internal/mock/ocilayout/ocilayout_test.go

@@ -0,0 +1,64 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ocilayout
+
+import (
+	"os"
+	"runtime"
+	"testing"
+)
+
+func TestCopy(t *testing.T) {
+	t.Run("empty oci layout", func(t *testing.T) {
+		err := Copy("", "", "v2")
+		if err == nil {
+			t.Errorf("expected error, got nil")
+		}
+	})
+
+	t.Run("invalid target path permission", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+		tempDir := t.TempDir()
+		// change the permission of the tempDir to make it invalid
+		if err := os.Chmod(tempDir, 0); err != nil {
+			t.Fatalf("failed to change the permission of the tempDir: %v", err)
+		}
+		err := Copy("../../testdata/oci-layout", tempDir, "v2")
+		if err == nil {
+			t.Errorf("expected error, got nil")
+		}
+
+		if err := os.Chmod(tempDir, 0755); err != nil {
+			t.Fatalf("failed to change the permission of the tempDir: %v", err)
+		}
+	})
+
+	t.Run("copy failed", func(t *testing.T) {
+		tempDir := t.TempDir()
+		err := Copy("../../testdata/oci-layout", tempDir, "v3")
+		if err == nil {
+			t.Errorf("expected error, got nil")
+		}
+	})
+
+	t.Run("copy success", func(t *testing.T) {
+		tempDir := t.TempDir()
+		err := Copy("../../testdata/oci-layout", tempDir, "v2")
+		if err != nil {
+			t.Errorf("expected nil, got %v", err)
+		}
+	})
+}

internal/pkix/fuzz_test.go

@@ -0,0 +1,24 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pkix
+
+import (
+	"testing"
+)
+
+func FuzzParseDistinguishedName(f *testing.F) {
+	f.Fuzz(func(t *testing.T, name string) {
+		_, _ = ParseDistinguishedName(name)
+	})
+}

internal/pkix/pkix.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package pkix
 
 import (
@@ -7,17 +20,16 @@ import (
 	ldapv3 "github.com/go-ldap/ldap/v3"
 )
 
-// ParseDistinguishedName parses a DN name and validates Notary V2 rules
+// ParseDistinguishedName parses a DN name and validates Notary Project rules
 func ParseDistinguishedName(name string) (map[string]string, error) {
 	if strings.Contains(name, "=#") {
 		return nil, fmt.Errorf("unsupported distinguished name (DN) %q: notation does not support x509.subject identities containing \"=#\"", name)
 	}
 
-	mandatoryFields := []string{"C", "ST", "O"}
 	attrKeyValue := make(map[string]string)
 	dn, err := ldapv3.ParseDN(name)
 	if err != nil {
-		return nil, fmt.Errorf("parsing distinguished name (DN) %q failed with err: %v. A valid DN must contain 'C', 'ST', and 'O' RDN attributes at a minimum, and follow RFC 4514 standard", name, err)
+		return nil, fmt.Errorf("parsing distinguished name (DN) %q failed with err: %v. A valid DN must contain 'C', 'ST' or 'S', and 'O' RDN attributes at a minimum, and follow RFC 4514 standard", name, err)
 	}
 
 	for _, rdn := range dn.RDNs {
@@ -26,6 +38,10 @@ func ParseDistinguishedName(name string) (map[string]string, error) {
 			return nil, fmt.Errorf("distinguished name (DN) %q has multi-valued RDN attributes, remove multi-valued RDN attributes as they are not supported", name)
 		}
 		for _, attribute := range rdn.Attributes {
+			// stateOrProvince name 'S' is an alias for 'ST'
+			if attribute.Type == "S" {
+				attribute.Type = "ST"
+			}
 			if attrKeyValue[attribute.Type] == "" {
 				attrKeyValue[attribute.Type] = attribute.Value
 			} else {
@@ -35,11 +51,13 @@ func ParseDistinguishedName(name string) (map[string]string, error) {
 	}
 
 	// Verify mandatory fields are present
+	mandatoryFields := []string{"C", "ST", "O"}
 	for _, field := range mandatoryFields {
 		if attrKeyValue[field] == "" {
-			return nil, fmt.Errorf("distinguished name (DN) %q has no mandatory RDN attribute for %q, it must contain 'C', 'ST', and 'O' RDN attributes at a minimum", name, field)
+			return nil, fmt.Errorf("distinguished name (DN) %q has no mandatory RDN attribute for %q, it must contain 'C', 'ST' or 'S', and 'O' RDN attributes at a minimum", name, field)
 		}
 	}
+
 	// No errors
 	return attrKeyValue, nil
 }

internal/pkix/pkix_test.go

@@ -0,0 +1,143 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pkix
+
+import "testing"
+
+func TestParseDistinguishedName(t *testing.T) {
+	// Test cases
+	tests := []struct {
+		name    string
+		input   string
+		wantErr bool
+	}{
+		{
+			name:    "valid DN",
+			input:   "C=US,ST=California,O=Notary Project",
+			wantErr: false,
+		},
+		{
+			name:    "valid DN with State alias",
+			input:   "C=US,S=California,O=Notary Project",
+			wantErr: false,
+		},
+		{
+			name:    "invalid DN",
+			input:   "C=US,ST=California",
+			wantErr: true,
+		},
+		{
+			name:    "invalid DN without State",
+			input:   "C=US,O=Notary Project",
+			wantErr: true,
+		},
+		{
+			name:    "invalid DN without State",
+			input:   "invalid",
+			wantErr: true,
+		},
+		{
+			name:    "duplicate RDN attribute",
+			input:   "C=US,ST=California,O=Notary Project,S=California",
+			wantErr: true,
+		},
+		{
+			name:    "unsupported DN =#",
+			input:   "C=US,ST=California,O=Notary Project=#",
+			wantErr: true,
+		},
+		{
+			name:    "multi-valued RDN attributes",
+			input:   "OU=Sales+CN=J.  Smith,DC=example,DC=net",
+			wantErr: true,
+		},
+	}
+
+	// Run tests
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			_, err := ParseDistinguishedName(tt.input)
+			if tt.wantErr != (err != nil) {
+				t.Errorf("ParseDistinguishedName() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestIsSubsetDN(t *testing.T) {
+	// Test cases
+	tests := []struct {
+		name string
+		dn1  map[string]string
+		dn2  map[string]string
+		want bool
+	}{
+		{
+			name: "subset DN",
+			dn1: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project",
+			},
+			dn2: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project",
+				"L":  "Los Angeles",
+			},
+			want: true,
+		},
+		{
+			name: "not subset DN",
+			dn1: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project",
+			},
+			dn2: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project 2",
+				"L":  "Los Angeles",
+				"CN": "Notary",
+			},
+			want: false,
+		},
+		{
+			name: "not subset DN 2",
+			dn1: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project",
+				"CN": "Notary",
+			},
+			dn2: map[string]string{
+				"C":  "US",
+				"ST": "California",
+				"O":  "Notary Project",
+				"L":  "Los Angeles",
+			},
+			want: false,
+		},
+	}
+
+	// Run tests
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := IsSubsetDN(tt.dn1, tt.dn2); got != tt.want {
+				t.Errorf("IsSubsetDN() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

internal/semver/semver.go

@@ -0,0 +1,49 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package semver provides functions related to semanic version.
+// This package is based on "golang.org/x/mod/semver"
+package semver
+
+import (
+	"fmt"
+	"regexp"
+
+	"golang.org/x/mod/semver"
+)
+
+// semVerRegEx is taken from https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string
+var semVerRegEx = regexp.MustCompile(`^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$`)
+
+// IsValid returns true if version is a valid semantic version
+func IsValid(version string) bool {
+	return semVerRegEx.MatchString(version)
+}
+
+// ComparePluginVersion validates and compares two plugin semantic versions.
+//
+// The result will be 0 if v == w, -1 if v < w, or +1 if v > w.
+func ComparePluginVersion(v, w string) (int, error) {
+	// sanity check
+	if !IsValid(v) {
+		return 0, fmt.Errorf("%s is not a valid semantic version", v)
+	}
+	if !IsValid(w) {
+		return 0, fmt.Errorf("%s is not a valid semantic version", w)
+	}
+
+	// golang.org/x/mod/semver requires semantic version strings must begin
+	// with a leading "v". Adding prefix "v" to the inputs.
+	// Reference: https://pkg.go.dev/golang.org/x/mod/semver#pkg-overview
+	return semver.Compare("v"+v, "v"+w), nil
+}

internal/semver/semver_test.go

@@ -0,0 +1,40 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package semver
+
+import "testing"
+
+func TestComparePluginVersion(t *testing.T) {
+	t.Run("compare with lower version", func(t *testing.T) {
+		comp, err := ComparePluginVersion("1.0.0", "1.0.1")
+		if err != nil || comp >= 0 {
+			t.Fatal("expected nil err and negative comp")
+		}
+	})
+
+	t.Run("compare with equal version", func(t *testing.T) {
+		comp, err := ComparePluginVersion("1.0.1", "1.0.1")
+		if err != nil || comp != 0 {
+			t.Fatal("expected nil err and comp equal to 0")
+		}
+	})
+
+	t.Run("failed due to invalid semantic version", func(t *testing.T) {
+		expectedErrMsg := "v1.0.0 is not a valid semantic version"
+		_, err := ComparePluginVersion("v1.0.0", "1.0.1")
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected err %s, but got %s", expectedErrMsg, err)
+		}
+	})
+}

internal/slices/slices.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package slices
 
 // Contains reports whether v is present in s.

internal/trustpolicy/trustpolicy.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package trustpolicy
 
 const (

log/log.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package log provides logging functionality to notation.
 // Users who want to enable logging option in notation should implement the
 // log.Logger interface and include it in context by calling log.WithLogger.

log/log_test.go

@@ -0,0 +1,41 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package log provides logging functionality to notation.
+// Users who want to enable logging option in notation should implement the
+// log.Logger interface and include it in context by calling log.WithLogger.
+// 3rd party loggers that implement log.Logger: github.com/uber-go/zap.SugaredLogger
+// and github.com/sirupsen/logrus.Logger.
+package log
+
+import (
+	"context"
+	"testing"
+)
+
+func TestWithLoggerAndGetLogger(t *testing.T) {
+	tl := &discardLogger{}
+	ctx := WithLogger(context.Background(), tl)
+
+	if got := GetLogger(ctx); got != tl {
+		t.Errorf("GetLogger() = %v, want %v", got, tl)
+	}
+}
+
+func TestGetLoggerWithNoLogger(t *testing.T) {
+	ctx := context.Background()
+
+	if got := GetLogger(ctx); got != Discard {
+		t.Errorf("GetLogger() = %v, want Discard", got)
+	}
+}

notation.go

@@ -1,33 +1,57 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package notation provides signer and verifier for notation Sign
-// and Verification.
+// and Verification. It supports both OCI artifact and arbitrary blob.
 package notation
 
 import (
 	"context"
 	"crypto/sha256"
+	"crypto/x509"
 	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
+	"mime"
 	"strings"
 	"time"
 
+	orasRegistry "oras.land/oras-go/v2/registry"
+	"oras.land/oras-go/v2/registry/remote"
+
+	"github.com/notaryproject/notation-core-go/revocation"
 	"github.com/notaryproject/notation-core-go/signature"
+	"github.com/notaryproject/notation-core-go/signature/cose"
+	"github.com/notaryproject/notation-core-go/signature/jws"
 	"github.com/notaryproject/notation-go/internal/envelope"
 	"github.com/notaryproject/notation-go/log"
 	"github.com/notaryproject/notation-go/registry"
 	"github.com/notaryproject/notation-go/verifier/trustpolicy"
+	"github.com/notaryproject/tspclient-go"
+	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
-	orasRegistry "oras.land/oras-go/v2/registry"
 )
 
 var errDoneVerification = errors.New("done verification")
+
 var reservedAnnotationPrefixes = [...]string{"io.cncf.notary"}
 
-// SignerSignOptions contains parameters for Signer.Sign.
+// SignerSignOptions contains parameters for [Signer] and [BlobSigner].
 type SignerSignOptions struct {
 	// SignatureMediaType is the envelope type of the signature.
-	// Currently both `application/jose+json` and `application/cose` are
+	// Currently, both `application/jose+json` and `application/cose` are
 	// supported.
 	SignatureMediaType string
 
@@ -40,17 +64,60 @@ type SignerSignOptions struct {
 
 	// SigningAgent sets the signing agent name
 	SigningAgent string
+
+	// Timestamper denotes the timestamper for RFC 3161 timestamping
+	Timestamper tspclient.Timestamper
+
+	// TSARootCAs is the cert pool holding caller's TSA trust anchor
+	TSARootCAs *x509.CertPool
+
+	// TSARevocationValidator is used for validating revocation status of
+	// timestamping certificate chain with context during signing.
+	// When present, only used when timestamping is performed.
+	TSARevocationValidator revocation.Validator
 }
 
-// Signer is a generic interface for signing an artifact.
+// Signer is a generic interface for signing an OCI artifact.
 // The interface allows signing with local or remote keys,
 // and packing in various signature formats.
 type Signer interface {
-	// Sign signs the artifact described by its descriptor,
+	// Sign signs the OCI artifact described by its descriptor,
 	// and returns the signature and SignerInfo.
 	Sign(ctx context.Context, desc ocispec.Descriptor, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error)
 }
 
+// SignBlobOptions contains parameters for [notation.SignBlob].
+type SignBlobOptions struct {
+	SignerSignOptions
+
+	// ContentMediaType is the media-type of the blob being signed.
+	ContentMediaType string
+
+	// UserMetadata contains key-value pairs that are added to the signature
+	// payload
+	UserMetadata map[string]string
+}
+
+// BlobDescriptorGenerator creates descriptor using the digest Algorithm.
+// Below is the example of minimal descriptor, it must contain mediatype,
+// digest and size of the artifact.
+//
+//	{
+//	   "mediaType": "application/octet-stream",
+//	   "digest": "sha256:2f3a23b6373afb134ddcd864be8e037e34a662d090d33ee849471ff73c873345",
+//	   "size": 1024
+//	}
+type BlobDescriptorGenerator func(digest.Algorithm) (ocispec.Descriptor, error)
+
+// BlobSigner is a generic interface for signing arbitrary data.
+// The interface allows signing with local or remote keys,
+// and packing in various signature formats.
+type BlobSigner interface {
+	// SignBlob signs the descriptor returned by genDesc, and returns the
+	// signature and SignerInfo.
+	SignBlob(ctx context.Context, genDesc BlobDescriptorGenerator, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error)
+}
+
 // signerAnnotation facilitates return of manifest annotations by signers
 type signerAnnotation interface {
 	// PluginAnnotations returns signature manifest annotations returned from
@@ -58,7 +125,7 @@ type signerAnnotation interface {
 	PluginAnnotations() map[string]string
 }
 
-// SignOptions contains parameters for notation.Sign.
+// SignOptions contains parameters for [notation.Sign].
 type SignOptions struct {
 	SignerSignOptions
 
@@ -71,21 +138,32 @@ type SignOptions struct {
 	UserMetadata map[string]string
 }
 
-// Sign signs the artifact and push the signature to the Repository.
-// The descriptor of the sign content is returned upon sucessful signing.
+// Sign signs the OCI artifact and push the signature to the Repository.
+// The descriptor of the sign content is returned upon successful signing.
+//
+// Deprecated: use [SignOCI] instead.
 func Sign(ctx context.Context, signer Signer, repo registry.Repository, signOpts SignOptions) (ocispec.Descriptor, error) {
+	artifactMenifestDesc, _, err := SignOCI(ctx, signer, repo, signOpts)
+	return artifactMenifestDesc, err
+}
+
+// SignOCI signs the OCI artifact and push the signature to the Repository.
+//
+// Both artifact and signature manifest descriptors are returned upon successful
+// signing.
+//
+// Note: If the error type is [remote.ReferrersError] and
+// referrerError.IsReferrersIndexDelete() returns true, the signature is
+// successfully pushed to the repository, but the referrers index deletion
+// failed. In this case, the artifact and signature manifest descriptors are
+// returned with the error.
+func SignOCI(ctx context.Context, signer Signer, repo registry.Repository, signOpts SignOptions) (artifactManifestDesc, sigManifestDesc ocispec.Descriptor, err error) {
 	// sanity check
-	if signer == nil {
-		return ocispec.Descriptor{}, errors.New("signer cannot be nil")
+	if err := validateSignArguments(signer, signOpts.SignerSignOptions); err != nil {
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, err
 	}
 	if repo == nil {
-		return ocispec.Descriptor{}, errors.New("repo cannot be nil")
-	}
-	if signOpts.ExpiryDuration < 0 {
-		return ocispec.Descriptor{}, fmt.Errorf("expiry duration cannot be a negative value")
-	}
-	if signOpts.ExpiryDuration%time.Second != 0 {
-		return ocispec.Descriptor{}, fmt.Errorf("expiry duration supports minimum granularity of seconds")
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, errors.New("repo cannot be nil")
 	}
 
 	logger := log.GetLogger(ctx)
@@ -94,68 +172,114 @@ func Sign(ctx context.Context, signer Signer, repo registry.Repository, signOpts
 		// artifactRef is a valid full reference
 		artifactRef = ref.Reference
 	}
-	targetDesc, err := repo.Resolve(ctx, artifactRef)
+	artifactManifestDesc, err = repo.Resolve(ctx, artifactRef)
 	if err != nil {
-		return ocispec.Descriptor{}, fmt.Errorf("failed to resolve reference: %w", err)
-	}
-	if artifactRef != targetDesc.Digest.String() {
-		// artifactRef is not a digest reference
-		logger.Warnf("Always sign the artifact using digest(`@sha256:...`) rather than a tag(`:%s`) because tags are mutable and a tag reference can point to a different artifact than the one signed", artifactRef)
-		logger.Infof("Resolved artifact tag `%s` to digest `%s` before signing", artifactRef, targetDesc.Digest.String())
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, fmt.Errorf("failed to resolve reference: %w", err)
 	}
 
-	descToSign, err := addUserMetadataToDescriptor(ctx, targetDesc, signOpts.UserMetadata)
+	// artifactRef is a tag or a digest, if it's a digest it has to match
+	// the resolved digest
+	if artifactRef != artifactManifestDesc.Digest.String() {
+		if _, err := digest.Parse(artifactRef); err == nil {
+			// artifactRef is a digest, but does not match the resolved digest
+			return ocispec.Descriptor{}, ocispec.Descriptor{}, fmt.Errorf("user input digest %s does not match the resolved digest %s", artifactRef, artifactManifestDesc.Digest.String())
+		}
+
+		// artifactRef is a tag
+		logger.Warnf("Always sign the artifact using digest(`@sha256:...`) rather than a tag(`:%s`) because tags are mutable and a tag reference can point to a different artifact than the one signed", artifactRef)
+		logger.Infof("Resolved artifact tag `%s` to digest `%v` before signing", artifactRef, artifactManifestDesc.Digest)
+	}
+	descToSign, err := addUserMetadataToDescriptor(ctx, artifactManifestDesc, signOpts.UserMetadata)
 	if err != nil {
-		return ocispec.Descriptor{}, err
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, err
 	}
 	sig, signerInfo, err := signer.Sign(ctx, descToSign, signOpts.SignerSignOptions)
 	if err != nil {
-		return ocispec.Descriptor{}, err
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, err
 	}
+
 	var pluginAnnotations map[string]string
 	if signerAnts, ok := signer.(signerAnnotation); ok {
 		pluginAnnotations = signerAnts.PluginAnnotations()
 	}
-
 	logger.Debug("Generating annotation")
 	annotations, err := generateAnnotations(signerInfo, pluginAnnotations)
 	if err != nil {
-		return ocispec.Descriptor{}, err
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, err
 	}
 	logger.Debugf("Generated annotations: %+v", annotations)
-	logger.Debugf("Pushing signature of artifact descriptor: %+v, signature media type: %v", targetDesc, signOpts.SignatureMediaType)
-	_, _, err = repo.PushSignature(ctx, signOpts.SignatureMediaType, sig, targetDesc, annotations)
+	logger.Debugf("Pushing signature of artifact descriptor: %+v, signature media type: %v", artifactManifestDesc, signOpts.SignatureMediaType)
+	_, sigManifestDesc, err = repo.PushSignature(ctx, signOpts.SignatureMediaType, sig, artifactManifestDesc, annotations)
 	if err != nil {
+		var referrerError *remote.ReferrersError
+		if errors.As(err, &referrerError) && referrerError.IsReferrersIndexDelete() {
+			// return the descriptors for referrersIndexDelete error as
+			// the signature is successfully pushed to the repository
+			return artifactManifestDesc, sigManifestDesc, err
+		}
 		logger.Error("Failed to push the signature")
-		return ocispec.Descriptor{}, ErrorPushSignatureFailed{Msg: err.Error()}
+		return ocispec.Descriptor{}, ocispec.Descriptor{}, ErrorPushSignatureFailed{Msg: err.Error()}
+	}
+	return artifactManifestDesc, sigManifestDesc, nil
+}
+
+// SignBlob signs the arbitrary data from blobReader and returns
+// the signature and SignerInfo.
+func SignBlob(ctx context.Context, signer BlobSigner, blobReader io.Reader, signBlobOpts SignBlobOptions) ([]byte, *signature.SignerInfo, error) {
+	// sanity checks
+	if err := validateSignArguments(signer, signBlobOpts.SignerSignOptions); err != nil {
+		return nil, nil, err
+	}
+	if blobReader == nil {
+		return nil, nil, errors.New("blobReader cannot be nil")
+	}
+	if signBlobOpts.ContentMediaType == "" {
+		return nil, nil, errors.New("content media-type cannot be empty")
+	}
+	if err := validateContentMediaType(signBlobOpts.ContentMediaType); err != nil {
+		return nil, nil, err
 	}
 
-	return targetDesc, nil
+	getDescFunc := getDescriptorFunc(ctx, blobReader, signBlobOpts.ContentMediaType, signBlobOpts.UserMetadata)
+	return signer.SignBlob(ctx, getDescFunc, signBlobOpts.SignerSignOptions)
+}
+
+func validateSignArguments(signer any, signOpts SignerSignOptions) error {
+	if signer == nil {
+		return errors.New("signer cannot be nil")
+	}
+	if signOpts.ExpiryDuration < 0 {
+		return errors.New("expiry duration cannot be a negative value")
+	}
+	if signOpts.ExpiryDuration%time.Second != 0 {
+		return errors.New("expiry duration supports minimum granularity of seconds")
+	}
+	if signOpts.SignatureMediaType == "" {
+		return errors.New("signature media-type cannot be empty")
+	}
+	if err := validateSigMediaType(signOpts.SignatureMediaType); err != nil {
+		return err
+	}
+	return nil
 }
 
 func addUserMetadataToDescriptor(ctx context.Context, desc ocispec.Descriptor, userMetadata map[string]string) (ocispec.Descriptor, error) {
 	logger := log.GetLogger(ctx)
-
 	if desc.Annotations == nil && len(userMetadata) > 0 {
 		desc.Annotations = map[string]string{}
 	}
-
 	for k, v := range userMetadata {
 		logger.Debugf("Adding metadata %v=%v to annotations", k, v)
-
 		for _, reservedPrefix := range reservedAnnotationPrefixes {
 			if strings.HasPrefix(k, reservedPrefix) {
 				return desc, fmt.Errorf("error adding user metadata: metadata key %v has reserved prefix %v", k, reservedPrefix)
 			}
 		}
-
 		if _, ok := desc.Annotations[k]; ok {
 			return desc, fmt.Errorf("error adding user metadata: metadata key %v is already present in the target artifact", k)
 		}
-
 		desc.Annotations[k] = v
 	}
-
 	return desc, nil
 }
 
@@ -174,7 +298,7 @@ type ValidationResult struct {
 	Error error
 }
 
-// VerificationOutcome encapsulates a signature blob's descriptor, its content,
+// VerificationOutcome encapsulates a signature envelope blob, its content,
 // the verification level and results for each verification type that was
 // performed.
 type VerificationOutcome struct {
@@ -197,6 +321,7 @@ type VerificationOutcome struct {
 	Error error
 }
 
+// UserMetadata returns the user metadata from the signature envelope.
 func (outcome *VerificationOutcome) UserMetadata() (map[string]string, error) {
 	if outcome.EnvelopeContent == nil {
 		return nil, errors.New("unable to find envelope content for verification outcome")
@@ -207,22 +332,21 @@ func (outcome *VerificationOutcome) UserMetadata() (map[string]string, error) {
 	if err != nil {
 		return nil, errors.New("failed to unmarshal the payload content in the signature blob to envelope.Payload")
 	}
-
 	if payload.TargetArtifact.Annotations == nil {
 		return map[string]string{}, nil
 	}
-
 	return payload.TargetArtifact.Annotations, nil
 }
 
-// VerifierVerifyOptions contains parameters for Verifier.Verify.
+// VerifierVerifyOptions contains parameters for [Verifier.Verify] used for
+// verifying OCI artifact.
 type VerifierVerifyOptions struct {
-	// ArtifactReference is the reference of the artifact that is been
+	// ArtifactReference is the reference of the artifact that is being
 	// verified against to. It must be a full reference.
 	ArtifactReference string
 
 	// SignatureMediaType is the envelope type of the signature.
-	// Currently both `application/jose+json` and `application/cose` are
+	// Currently only `application/jose+json` and `application/cose` are
 	// supported.
 	SignatureMediaType string
 
@@ -234,24 +358,51 @@ type VerifierVerifyOptions struct {
 	UserMetadata map[string]string
 }
 
-// Verifier is a generic interface for verifying an artifact.
+// Verifier is a generic interface for verifying an OCI artifact.
 type Verifier interface {
-	// Verify verifies the signature blob `signature` against the target OCI
-	// artifact with manifest descriptor `desc`, and returns the outcome upon
+	// Verify verifies the `signature` associated with the target OCI artifact
+	// with manifest descriptor `desc`, and returns the outcome upon
 	// successful verification.
 	// If nil signature is present and the verification level is not 'skip',
 	// an error will be returned.
 	Verify(ctx context.Context, desc ocispec.Descriptor, signature []byte, opts VerifierVerifyOptions) (*VerificationOutcome, error)
 }
 
+// BlobVerifierVerifyOptions contains parameters for [BlobVerifier.Verify].
+type BlobVerifierVerifyOptions struct {
+	// SignatureMediaType is the envelope type of the signature.
+	// Currently only `application/jose+json` and `application/cose` are
+	// supported.
+	SignatureMediaType string
+
+	// PluginConfig is a map of plugin configs.
+	PluginConfig map[string]string
+
+	// UserMetadata contains key-value pairs that must be present in the
+	// signature.
+	UserMetadata map[string]string
+
+	// TrustPolicyName is the name of trust policy picked by caller.
+	// If empty, the global trust policy will be applied.
+	TrustPolicyName string
+}
+
+// BlobVerifier is a generic interface for verifying a blob.
+type BlobVerifier interface {
+	// VerifyBlob verifies the `signature` against the target blob using the
+	// descriptor returned by descGenFunc parameter and
+	// returns the outcome upon successful verification.
+	VerifyBlob(ctx context.Context, descGenFunc BlobDescriptorGenerator, signature []byte, opts BlobVerifierVerifyOptions) (*VerificationOutcome, error)
+}
+
 type verifySkipper interface {
 	// SkipVerify validates whether the verification level is skip.
 	SkipVerify(ctx context.Context, opts VerifierVerifyOptions) (bool, *trustpolicy.VerificationLevel, error)
 }
 
-// VerifyOptions contains parameters for notation.Verify.
+// VerifyOptions contains parameters for [notation.Verify].
 type VerifyOptions struct {
-	// ArtifactReference is the reference of the artifact that is been
+	// ArtifactReference is the reference of the artifact that is being
 	// verified against to.
 	ArtifactReference string
 
@@ -268,8 +419,51 @@ type VerifyOptions struct {
 	UserMetadata map[string]string
 }
 
+// VerifyBlobOptions contains parameters for [notation.VerifyBlob].
+type VerifyBlobOptions struct {
+	BlobVerifierVerifyOptions
+
+	// ContentMediaType is the media-type type of the content being verified.
+	ContentMediaType string
+}
+
+// VerifyBlob performs signature verification for a blob using notation supported
+// verification types (like integrity, authenticity, etc.) and returns the
+// successful signature verification outcome. The blob is read using blobReader,
+// and upon successful verification, it returns the descriptor of the blob.
+// For more details on signature verification, see
+// https://github.com/notaryproject/notaryproject/blob/main/specs/trust-store-trust-policy.md#signature-verification
+func VerifyBlob(ctx context.Context, blobVerifier BlobVerifier, blobReader io.Reader, signature []byte, verifyBlobOpts VerifyBlobOptions) (ocispec.Descriptor, *VerificationOutcome, error) {
+	if blobVerifier == nil {
+		return ocispec.Descriptor{}, nil, errors.New("blobVerifier cannot be nil")
+	}
+	if blobReader == nil {
+		return ocispec.Descriptor{}, nil, errors.New("blobReader cannot be nil")
+	}
+	if len(signature) == 0 {
+		return ocispec.Descriptor{}, nil, errors.New("signature cannot be nil or empty")
+	}
+	if err := validateContentMediaType(verifyBlobOpts.ContentMediaType); err != nil {
+		return ocispec.Descriptor{}, nil, err
+	}
+	if err := validateSigMediaType(verifyBlobOpts.SignatureMediaType); err != nil {
+		return ocispec.Descriptor{}, nil, err
+	}
+	getDescFunc := getDescriptorFunc(ctx, blobReader, verifyBlobOpts.ContentMediaType, verifyBlobOpts.UserMetadata)
+	vo, err := blobVerifier.VerifyBlob(ctx, getDescFunc, signature, verifyBlobOpts.BlobVerifierVerifyOptions)
+	if err != nil {
+		return ocispec.Descriptor{}, nil, err
+	}
+
+	var desc ocispec.Descriptor
+	if err = json.Unmarshal(vo.EnvelopeContent.Payload.Content, &desc); err != nil {
+		return ocispec.Descriptor{}, nil, err
+	}
+	return desc, vo, nil
+}
+
 // Verify performs signature verification on each of the notation supported
-// verification types (like integrity, authenticity, etc.) and return the
+// verification types (like integrity, authenticity, etc.) and returns the
 // successful signature verification outcome.
 // For more details on signature verification, see
 // https://github.com/notaryproject/notaryproject/blob/main/specs/trust-store-trust-policy.md#signature-verification
@@ -293,7 +487,6 @@ func Verify(ctx context.Context, verifier Verifier, repo registry.Repository, ve
 		PluginConfig:      verifyOpts.PluginConfig,
 		UserMetadata:      verifyOpts.UserMetadata,
 	}
-
 	if skipChecker, ok := verifier.(verifySkipper); ok {
 		logger.Info("Checking whether signature verification should be skipped or not")
 		skip, verificationLevel, err := skipChecker.SkipVerify(ctx, opts)
@@ -301,10 +494,10 @@ func Verify(ctx context.Context, verifier Verifier, repo registry.Repository, ve
 			return ocispec.Descriptor{}, nil, err
 		}
 		if skip {
-			logger.Infoln("Verification skipped for", verifyOpts.ArtifactReference)
+			logger.Infoln("Signature verification skipped for", verifyOpts.ArtifactReference)
 			return ocispec.Descriptor{}, []*VerificationOutcome{{VerificationLevel: verificationLevel}}, nil
 		}
-		logger.Info("Check over. Trust policy is not configured to skip signature verification")
+		logger.Info("Check over. The signature verification level is not set to 'skip' in the trust policy.")
 	}
 
 	// get artifact descriptor
@@ -322,16 +515,18 @@ func Verify(ctx context.Context, verifier Verifier, repo registry.Repository, ve
 	}
 	if ref.ValidateReferenceAsDigest() != nil {
 		// artifactRef is not a digest reference
-		logger.Infof("Resolved artifact tag `%s` to digest `%s` before verification", ref.Reference, artifactDescriptor.Digest.String())
+		logger.Infof("Resolved artifact tag `%s` to digest `%v` before verification", ref.Reference, artifactDescriptor.Digest)
 		logger.Warn("The resolved digest may not point to the same signed artifact, since tags are mutable")
+	} else if ref.Reference != artifactDescriptor.Digest.String() {
+		return ocispec.Descriptor{}, nil, ErrorSignatureRetrievalFailed{Msg: fmt.Sprintf("user input digest %s does not match the resolved digest %s", ref.Reference, artifactDescriptor.Digest.String())}
 	}
 
+	var verificationSucceeded bool
 	var verificationOutcomes []*VerificationOutcome
-	errExceededMaxVerificationLimit := ErrorVerificationFailed{Msg: fmt.Sprintf("total number of signatures associated with an artifact should be at most: %d", verifyOpts.MaxSignatureAttempts)}
+	var verificationFailedErrorArray = []error{ErrorVerificationFailed{}}
+	errExceededMaxVerificationLimit := ErrorVerificationFailed{Msg: fmt.Sprintf("signature evaluation stopped. The configured limit of %d signatures to verify per artifact exceeded", verifyOpts.MaxSignatureAttempts)}
 	numOfSignatureProcessed := 0
 
-	var verificationFailedErr error = ErrorVerificationFailed{}
-
 	// get signature manifests
 	logger.Debug("Fetching signature manifests")
 	err = repo.ListSignatures(ctx, artifactDescriptor, func(signatureManifests []ocispec.Descriptor) error {
@@ -359,29 +554,26 @@ func Verify(ctx context.Context, verifier Verifier, repo registry.Repository, ve
 					logger.Error("Got nil outcome. Expecting non-nil outcome on verification failure")
 					return err
 				}
-
-				if _, ok := outcome.Error.(ErrorUserMetadataVerificationFailed); ok {
-					verificationFailedErr = outcome.Error
-				}
-
+				outcome.Error = fmt.Errorf("failed to verify signature with digest %v, %w", sigManifestDesc.Digest, outcome.Error)
+				verificationFailedErrorArray = append(verificationFailedErrorArray, outcome.Error)
 				continue
 			}
-			// at this point, the signature is verified successfully. Add
-			// it to the verificationOutcomes.
-			verificationOutcomes = append(verificationOutcomes, outcome)
+			// at this point, the signature is verified successfully
+			verificationSucceeded = true
+
+			// on success, verificationOutcomes only contains the
+			// succeeded outcome
+			verificationOutcomes = []*VerificationOutcome{outcome}
 			logger.Debugf("Signature verification succeeded for artifact %v with signature digest %v", artifactDescriptor.Digest, sigManifestDesc.Digest)
 
 			// early break on success
 			return errDoneVerification
 		}
-
 		if numOfSignatureProcessed >= verifyOpts.MaxSignatureAttempts {
 			return errExceededMaxVerificationLimit
 		}
-
 		return nil
 	})
-
 	if err != nil && !errors.Is(err, errDoneVerification) {
 		if errors.Is(err, errExceededMaxVerificationLimit) {
 			return ocispec.Descriptor{}, verificationOutcomes, err
@@ -395,9 +587,9 @@ func Verify(ctx context.Context, verifier Verifier, repo registry.Repository, ve
 	}
 
 	// Verification Failed
-	if len(verificationOutcomes) == 0 {
+	if !verificationSucceeded {
 		logger.Debugf("Signature verification failed for all the signatures associated with artifact %v", artifactDescriptor.Digest)
-		return ocispec.Descriptor{}, verificationOutcomes, verificationFailedErr
+		return ocispec.Descriptor{}, verificationOutcomes, errors.Join(verificationFailedErrorArray...)
 	}
 
 	// Verification Succeeded
@@ -429,3 +621,35 @@ func generateAnnotations(signerInfo *signature.SignerInfo, annotations map[strin
 	annotations[ocispec.AnnotationCreated] = signingTime.Format(time.RFC3339)
 	return annotations, nil
 }
+
+func getDescriptorFunc(ctx context.Context, reader io.Reader, contentMediaType string, userMetadata map[string]string) BlobDescriptorGenerator {
+	return func(hashAlgo digest.Algorithm) (ocispec.Descriptor, error) {
+		digester := hashAlgo.Digester()
+		bytes, err := io.Copy(digester.Hash(), reader)
+		if err != nil {
+			return ocispec.Descriptor{}, err
+		}
+		targetDesc := ocispec.Descriptor{
+			MediaType: contentMediaType,
+			Digest:    digester.Digest(),
+			Size:      bytes,
+		}
+		return addUserMetadataToDescriptor(ctx, targetDesc, userMetadata)
+	}
+}
+
+func validateContentMediaType(contentMediaType string) error {
+	if contentMediaType != "" {
+		if _, _, err := mime.ParseMediaType(contentMediaType); err != nil {
+			return fmt.Errorf("invalid content media-type %q: %v", contentMediaType, err)
+		}
+	}
+	return nil
+}
+
+func validateSigMediaType(sigMediaType string) error {
+	if !(sigMediaType == jws.MediaTypeEnvelope || sigMediaType == cose.MediaTypeEnvelope) {
+		return fmt.Errorf("invalid signature media-type %q", sigMediaType)
+	}
+	return nil
+}

notation_test.go

@@ -1,21 +1,43 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package notation
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"math"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 	"time"
 
+	"oras.land/oras-go/v2/registry/remote"
+
 	"github.com/notaryproject/notation-core-go/signature"
 	"github.com/notaryproject/notation-core-go/signature/cose"
+	"github.com/notaryproject/notation-core-go/signature/jws"
+	"github.com/notaryproject/notation-go/internal/envelope"
 	"github.com/notaryproject/notation-go/internal/mock"
+	"github.com/notaryproject/notation-go/internal/mock/ocilayout"
 	"github.com/notaryproject/notation-go/plugin"
 	"github.com/notaryproject/notation-go/registry"
 	"github.com/notaryproject/notation-go/verifier/trustpolicy"
+	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
@@ -34,6 +56,7 @@ func TestSignSuccess(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(b *testing.T) {
 			opts := SignOptions{}
+			opts.SignatureMediaType = jws.MediaTypeEnvelope
 			opts.ExpiryDuration = tc.dur
 			opts.ArtifactReference = mock.SampleArtifactUri
 
@@ -45,11 +68,91 @@ func TestSignSuccess(t *testing.T) {
 	}
 }
 
+func TestSignBlobSuccess(t *testing.T) {
+	reader := strings.NewReader("some content")
+	testCases := []struct {
+		name     string
+		dur      time.Duration
+		mtype    string
+		agent    string
+		pConfig  map[string]string
+		metadata map[string]string
+	}{
+		{"expiryInHours", 24 * time.Hour, "video/mp4", "", nil, nil},
+		{"oneSecondExpiry", 1 * time.Second, "video/mp4", "", nil, nil},
+		{"zeroExpiry", 0, "video/mp4", "", nil, nil},
+		{"validContentType", 1 * time.Second, "video/mp4", "", nil, nil},
+		{"emptyContentType", 1 * time.Second, "video/mp4", "someDummyAgent", map[string]string{"hi": "hello"}, map[string]string{"bye": "tata"}},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(b *testing.T) {
+			opts := SignBlobOptions{
+				SignerSignOptions: SignerSignOptions{
+					SignatureMediaType: jws.MediaTypeEnvelope,
+					ExpiryDuration:     tc.dur,
+					PluginConfig:       tc.pConfig,
+					SigningAgent:       tc.agent,
+				},
+				UserMetadata:     expectedMetadata,
+				ContentMediaType: tc.mtype,
+			}
+
+			_, _, err := SignBlob(context.Background(), &dummySigner{}, reader, opts)
+			if err != nil {
+				b.Fatalf("Sign failed with error: %v", err)
+			}
+		})
+	}
+}
+
+func TestSignBlobError(t *testing.T) {
+	reader := strings.NewReader("some content")
+	testCases := []struct {
+		name     string
+		signer   BlobSigner
+		dur      time.Duration
+		rdr      io.Reader
+		sigMType string
+		ctMType  string
+		errMsg   string
+	}{
+		{"negativeExpiry", &dummySigner{}, -1 * time.Second, nil, "video/mp4", jws.MediaTypeEnvelope, "expiry duration cannot be a negative value"},
+		{"milliSecExpiry", &dummySigner{}, 1 * time.Millisecond, nil, "video/mp4", jws.MediaTypeEnvelope, "expiry duration supports minimum granularity of seconds"},
+		{"invalidContentMediaType", &dummySigner{}, 1 * time.Second, reader, "video/mp4/zoping", jws.MediaTypeEnvelope, "invalid content media-type \"video/mp4/zoping\": mime: unexpected content after media subtype"},
+		{"emptyContentMediaType", &dummySigner{}, 1 * time.Second, reader, "", jws.MediaTypeEnvelope, "content media-type cannot be empty"},
+		{"invalidSignatureMediaType", &dummySigner{}, 1 * time.Second, reader, "", "", "content media-type cannot be empty"},
+		{"nilReader", &dummySigner{}, 1 * time.Second, nil, "video/mp4", jws.MediaTypeEnvelope, "blobReader cannot be nil"},
+		{"nilSigner", nil, 1 * time.Second, reader, "video/mp4", jws.MediaTypeEnvelope, "signer cannot be nil"},
+		{"signerError", &dummySigner{fail: true}, 1 * time.Second, reader, "video/mp4", jws.MediaTypeEnvelope, "expected SignBlob failure"},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			opts := SignBlobOptions{
+				SignerSignOptions: SignerSignOptions{
+					SignatureMediaType: jws.MediaTypeEnvelope,
+					ExpiryDuration:     tc.dur,
+					PluginConfig:       nil,
+				},
+				ContentMediaType: tc.sigMType,
+			}
+
+			_, _, err := SignBlob(context.Background(), tc.signer, tc.rdr, opts)
+			if err == nil {
+				t.Fatalf("expected error but didnt found")
+			}
+			if err.Error() != tc.errMsg {
+				t.Fatalf("expected err message to be '%s' but found '%s'", tc.errMsg, err.Error())
+			}
+		})
+	}
+}
+
 func TestSignSuccessWithUserMetadata(t *testing.T) {
 	repo := mock.NewRepository()
 	opts := SignOptions{}
 	opts.ArtifactReference = mock.SampleArtifactUri
 	opts.UserMetadata = expectedMetadata
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
 
 	_, err := Sign(context.Background(), &verifyMetadataSigner{}, repo, opts)
 	if err != nil {
@@ -57,6 +160,71 @@ func TestSignSuccessWithUserMetadata(t *testing.T) {
 	}
 }
 
+func TestSignWithDanglingReferrersIndex(t *testing.T) {
+	repo := mock.NewRepository()
+	repo.PushSignatureError = &remote.ReferrersError{
+		Op:  "DeleteReferrersIndex",
+		Err: errors.New("error"),
+	}
+	opts := SignOptions{}
+	opts.ArtifactReference = mock.SampleArtifactUri
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err == nil {
+		t.Fatalf("no error occurred, expected error")
+	}
+}
+
+func TestSignWithNilRepo(t *testing.T) {
+	opts := SignOptions{}
+	opts.ArtifactReference = mock.SampleArtifactUri
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
+
+	_, err := Sign(context.Background(), &dummySigner{}, nil, opts)
+	if err == nil {
+		t.Fatalf("no error occurred, expected error: repo cannot be nil")
+	}
+}
+
+func TestSignResolveFailed(t *testing.T) {
+	repo := mock.NewRepository()
+	repo.ResolveError = errors.New("resolve error")
+	opts := SignOptions{}
+	opts.ArtifactReference = mock.SampleArtifactUri
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err == nil {
+		t.Fatalf("no error occurred, expected resolve error")
+	}
+}
+
+func TestSignArtifactRefIsTag(t *testing.T) {
+	repo := mock.NewRepository()
+	opts := SignOptions{}
+	opts.ArtifactReference = "registry.acme-rockets.io/software/net-monitor:v1"
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err != nil {
+		t.Fatalf("expect no error, got %s", err)
+	}
+}
+
+func TestSignWithPushSignatureError(t *testing.T) {
+	repo := mock.NewRepository()
+	repo.PushSignatureError = errors.New("error")
+	opts := SignOptions{}
+	opts.ArtifactReference = mock.SampleArtifactUri
+	opts.SignatureMediaType = jws.MediaTypeEnvelope
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err == nil {
+		t.Fatalf("no error occurred, expected error: failed to delete dangling referrers index")
+	}
+}
+
 func TestSignWithInvalidExpiry(t *testing.T) {
 	repo := mock.NewRepository()
 	testCases := []struct {
@@ -90,7 +258,14 @@ func TestSignWithInvalidUserMetadata(t *testing.T) {
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(b *testing.T) {
-			_, err := Sign(context.Background(), &dummySigner{}, repo, SignOptions{UserMetadata: tc.metadata})
+			opts := SignOptions{
+				UserMetadata: tc.metadata,
+				SignerSignOptions: SignerSignOptions{
+					SignatureMediaType: jws.MediaTypeEnvelope,
+				},
+			}
+
+			_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
 			if err == nil {
 				b.Fatalf("Expected error but not found")
 			}
@@ -98,10 +273,41 @@ func TestSignWithInvalidUserMetadata(t *testing.T) {
 	}
 }
 
-func TestRegistryResolveError(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
+func TestSignOptsMissingSignatureMediaType(t *testing.T) {
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	opts := SignOptions{
+		SignerSignOptions: SignerSignOptions{
+			SignatureMediaType: "",
+		},
+		ArtifactReference: mock.SampleArtifactUri,
+	}
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err == nil {
+		t.Fatalf("expected error but not found")
+	}
+}
+
+func TestSignOptsUnknownMediaType(t *testing.T) {
+	repo := mock.NewRepository()
+	opts := SignOptions{
+		SignerSignOptions: SignerSignOptions{
+			SignatureMediaType: "unknown",
+		},
+		ArtifactReference: mock.SampleArtifactUri,
+	}
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, opts)
+	if err == nil {
+		t.Fatalf("expected error but not found")
+	}
+
+}
+
+func TestRegistryResolveError(t *testing.T) {
+	repo := mock.NewRepository()
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 
 	errorMessage := "network error"
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
@@ -117,9 +323,9 @@ func TestRegistryResolveError(t *testing.T) {
 }
 
 func TestVerifyEmptyReference(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 
 	errorMessage := "reference is missing digest or tag"
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
@@ -133,11 +339,11 @@ func TestVerifyEmptyReference(t *testing.T) {
 }
 
 func TestVerifyTagReferenceFailed(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 
-	errorMessage := "invalid reference: invalid repository"
+	errorMessage := "invalid reference: invalid repository \"UPPERCASE/test\""
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
 
 	// mock the repository
@@ -148,10 +354,46 @@ func TestVerifyTagReferenceFailed(t *testing.T) {
 	}
 }
 
-func TestSkippedSignatureVerification(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
+func TestVerifyDigestNotMatchResolve(t *testing.T) {
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelSkip}
+	repo.MissMatchDigest = true
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
+
+	errorMessage := fmt.Sprintf("user input digest %s does not match the resolved digest %s", mock.SampleDigest, mock.ZeroDigest)
+	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
+
+	// mock the repository
+	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+	_, _, err := Verify(context.Background(), &verifier, repo, opts)
+	if err == nil || err.Error() != errorMessage {
+		t.Fatalf("VerifyDigestNotMatch expected: %v got: %v", expectedErr, err)
+	}
+}
+
+func TestSignDigestNotMatchResolve(t *testing.T) {
+	repo := mock.NewRepository()
+	repo.MissMatchDigest = true
+	signOpts := SignOptions{
+		SignerSignOptions: SignerSignOptions{
+			SignatureMediaType: jws.MediaTypeEnvelope,
+		},
+		ArtifactReference: mock.SampleArtifactUri,
+	}
+
+	errorMessage := fmt.Sprintf("user input digest %s does not match the resolved digest %s", mock.SampleDigest, mock.ZeroDigest)
+	expectedErr := errors.New(errorMessage)
+
+	_, err := Sign(context.Background(), &dummySigner{}, repo, signOpts)
+	if err == nil || err.Error() != errorMessage {
+		t.Fatalf("SignDigestNotMatch expected: %v got: %v", expectedErr, err)
+	}
+}
+
+func TestSkippedSignatureVerification(t *testing.T) {
+	repo := mock.NewRepository()
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelSkip, false}
 
 	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
 	_, outcomes, err := Verify(context.Background(), &verifier, repo, opts)
@@ -162,9 +404,9 @@ func TestSkippedSignatureVerification(t *testing.T) {
 }
 
 func TestRegistryNoSignatureManifests(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 	errorMessage := fmt.Sprintf("no signature is associated with %q, make sure the artifact was signed successfully", mock.SampleArtifactUri)
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
 
@@ -179,9 +421,9 @@ func TestRegistryNoSignatureManifests(t *testing.T) {
 }
 
 func TestRegistryFetchSignatureBlobError(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 	errorMessage := fmt.Sprintf("unable to retrieve digital signature with digest %q associated with %q from the Repository, error : network error", mock.SampleDigest, mock.SampleArtifactUri)
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: errorMessage}
 
@@ -196,23 +438,37 @@ func TestRegistryFetchSignatureBlobError(t *testing.T) {
 }
 
 func TestVerifyValid(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 
 	// mock the repository
 	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
 	_, _, err := Verify(context.Background(), &verifier, repo, opts)
 
 	if err != nil {
-		t.Fatalf("SignaureMediaTypeMismatch expected: %v got: %v", nil, err)
+		t.Fatalf("expected nil error, but got: %v", err)
+	}
+}
+
+func TestVerifySkip(t *testing.T) {
+	repo := mock.NewRepository()
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, true}
+
+	// mock the repository
+	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+	_, _, err := Verify(context.Background(), &verifier, repo, opts)
+
+	if err != nil {
+		t.Fatalf("expected nil error, but got: %v", err)
 	}
 }
 
 func TestMaxSignatureAttemptsMissing(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
 	expectedErr := ErrorSignatureRetrievalFailed{Msg: fmt.Sprintf("verifyOptions.MaxSignatureAttempts expects a positive number, got %d", 0)}
 
 	// mock the repository
@@ -224,14 +480,16 @@ func TestMaxSignatureAttemptsMissing(t *testing.T) {
 	}
 }
 
-func TestVerifyFailed(t *testing.T) {
-	policyDocument := dummyPolicyDocument()
+func TestExceededMaxSignatureAttempts(t *testing.T) {
 	repo := mock.NewRepository()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, true, *trustpolicy.LevelStrict}
-	expectedErr := ErrorVerificationFailed{}
+	repo.ExceededNumOfSignatures = true
+	policyDocument := dummyPolicyDocument()
+	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, true, *trustpolicy.LevelStrict, false}
+
+	expectedErr := ErrorVerificationFailed{Msg: fmt.Sprintf("signature evaluation stopped. The configured limit of %d signatures to verify per artifact exceeded", 1)}
 
 	// mock the repository
-	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+	opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 1}
 	_, _, err := Verify(context.Background(), &verifier, repo, opts)
 
 	if err == nil || !errors.Is(err, expectedErr) {
@@ -239,16 +497,117 @@ func TestVerifyFailed(t *testing.T) {
 	}
 }
 
-func dummyPolicyDocument() (policyDoc trustpolicy.Document) {
-	policyDoc = trustpolicy.Document{
+func TestVerifyFailed(t *testing.T) {
+	t.Run("verification error", func(t *testing.T) {
+		policyDocument := dummyPolicyDocument()
+		repo := mock.NewRepository()
+		verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, true, *trustpolicy.LevelStrict, false}
+		expectedErr := ErrorVerificationFailed{}
+
+		// mock the repository
+		opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+		_, _, err := Verify(context.Background(), &verifier, repo, opts)
+
+		if err == nil || !errors.Is(err, expectedErr) {
+			t.Fatalf("VerificationFailed expected: %v got: %v", expectedErr, err)
+		}
+	})
+
+	t.Run("verifier is nil", func(t *testing.T) {
+		repo := mock.NewRepository()
+		expectedErr := errors.New("verifier cannot be nil")
+
+		// mock the repository
+		opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+		_, _, err := Verify(context.Background(), nil, repo, opts)
+
+		if err == nil || err.Error() != expectedErr.Error() {
+			t.Fatalf("VerificationFailed expected: %v got: %v", expectedErr, err)
+		}
+	})
+
+	t.Run("repo is nil", func(t *testing.T) {
+		policyDocument := dummyPolicyDocument()
+		verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
+		expectedErr := errors.New("repo cannot be nil")
+
+		// mock the repository
+		opts := VerifyOptions{ArtifactReference: mock.SampleArtifactUri, MaxSignatureAttempts: 50}
+		_, _, err := Verify(context.Background(), &verifier, nil, opts)
+
+		if err == nil || err.Error() != expectedErr.Error() {
+			t.Fatalf("VerificationFailed expected: %v got: %v", expectedErr, err)
+		}
+	})
+}
+
+func TestVerifyBlobError(t *testing.T) {
+	reader := strings.NewReader("some content")
+	sig := []byte("signature")
+	testCases := []struct {
+		name     string
+		verifier BlobVerifier
+		sig      []byte
+		rdr      io.Reader
+		ctMType  string
+		sigMType string
+		errMsg   string
+	}{
+		{"nilVerifier", nil, sig, reader, "video/mp4", jws.MediaTypeEnvelope, "blobVerifier cannot be nil"},
+		{"verifierError", &dummyVerifier{FailVerify: true}, sig, reader, "video/mp4", jws.MediaTypeEnvelope, "failed verify"},
+		{"nilSignature", &dummyVerifier{}, nil, reader, "video/mp4", jws.MediaTypeEnvelope, "signature cannot be nil or empty"},
+		{"emptySignature", &dummyVerifier{}, []byte{}, reader, "video/mp4", jws.MediaTypeEnvelope, "signature cannot be nil or empty"},
+		{"nilReader", &dummyVerifier{}, sig, nil, "video/mp4", jws.MediaTypeEnvelope, "blobReader cannot be nil"},
+		{"invalidContentType", &dummyVerifier{}, sig, reader, "video/mp4/zoping", jws.MediaTypeEnvelope, "invalid content media-type \"video/mp4/zoping\": mime: unexpected content after media subtype"},
+		{"invalidSigType", &dummyVerifier{}, sig, reader, "video/mp4", "hola!", "invalid signature media-type \"hola!\""},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			opts := VerifyBlobOptions{
+				BlobVerifierVerifyOptions: BlobVerifierVerifyOptions{
+					SignatureMediaType: tc.sigMType,
+					UserMetadata:       nil,
+					TrustPolicyName:    "",
+				},
+				ContentMediaType: tc.ctMType,
+			}
+
+			_, _, err := VerifyBlob(context.Background(), tc.verifier, tc.rdr, tc.sig, opts)
+			if err == nil {
+				t.Fatalf("expected error but didnt found")
+			}
+			if err.Error() != tc.errMsg {
+				t.Fatalf("expected err message to be '%s' but found '%s'", tc.errMsg, err.Error())
+			}
+		})
+	}
+}
+
+func TestVerifyBlobValid(t *testing.T) {
+	opts := VerifyBlobOptions{
+		BlobVerifierVerifyOptions: BlobVerifierVerifyOptions{
+			SignatureMediaType: jws.MediaTypeEnvelope,
+			UserMetadata:       nil,
+			TrustPolicyName:    "",
+		},
+	}
+
+	_, _, err := VerifyBlob(context.Background(), &dummyVerifier{}, strings.NewReader("some content"), []byte("signature"), opts)
+	if err != nil {
+		t.Fatalf("expected nil error, but got: %v", err)
+	}
+}
+
+func dummyPolicyDocument() (policyDoc trustpolicy.OCIDocument) {
+	policyDoc = trustpolicy.OCIDocument{
 		Version:       "1.0",
-		TrustPolicies: []trustpolicy.TrustPolicy{dummyPolicyStatement()},
+		TrustPolicies: []trustpolicy.OCITrustPolicy{dummyPolicyStatement()},
 	}
 	return
 }
 
-func dummyPolicyStatement() (policyStatement trustpolicy.TrustPolicy) {
-	policyStatement = trustpolicy.TrustPolicy{
+func dummyPolicyStatement() (policyStatement trustpolicy.OCITrustPolicy) {
+	policyStatement = trustpolicy.OCITrustPolicy{
 		Name:                  "test-statement-name",
 		RegistryScopes:        []string{"registry.acme-rockets.io/software/net-monitor"},
 		SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: "strict"},
@@ -258,9 +617,28 @@ func dummyPolicyStatement() (policyStatement trustpolicy.TrustPolicy) {
 	return
 }
 
-type dummySigner struct{}
+type dummySigner struct {
+	fail bool
+}
+
+func (s *dummySigner) Sign(_ context.Context, _ ocispec.Descriptor, _ SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+	return []byte("ABC"), &signature.SignerInfo{
+		SignedAttributes: signature.SignedAttributes{
+			SigningTime: time.Now(),
+		},
+	}, nil
+}
+
+func (s *dummySigner) SignBlob(_ context.Context, descGenFunc BlobDescriptorGenerator, _ SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+	if s.fail {
+		return nil, nil, errors.New("expected SignBlob failure")
+	}
+
+	_, err := descGenFunc(digest.SHA384)
+	if err != nil {
+		return nil, nil, err
+	}
 
-func (s *dummySigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	return []byte("ABC"), &signature.SignerInfo{
 		SignedAttributes: signature.SignedAttributes{
 			SigningTime: time.Now(),
@@ -270,7 +648,7 @@ func (s *dummySigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts Si
 
 type verifyMetadataSigner struct{}
 
-func (s *verifyMetadataSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+func (s *verifyMetadataSigner) Sign(_ context.Context, desc ocispec.Descriptor, _ SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	for k, v := range expectedMetadata {
 		if desc.Annotations[k] != v {
 			return nil, nil, errors.New("expected metadata not present in descriptor")
@@ -284,13 +662,14 @@ func (s *verifyMetadataSigner) Sign(ctx context.Context, desc ocispec.Descriptor
 }
 
 type dummyVerifier struct {
-	TrustPolicyDoc    *trustpolicy.Document
+	TrustPolicyDoc    *trustpolicy.OCIDocument
 	PluginManager     plugin.Manager
 	FailVerify        bool
 	VerificationLevel trustpolicy.VerificationLevel
+	SkipVerification  bool
 }
 
-func (v *dummyVerifier) Verify(ctx context.Context, desc ocispec.Descriptor, signature []byte, opts VerifierVerifyOptions) (*VerificationOutcome, error) {
+func (v *dummyVerifier) Verify(_ context.Context, _ ocispec.Descriptor, _ []byte, _ VerifierVerifyOptions) (*VerificationOutcome, error) {
 	outcome := &VerificationOutcome{
 		VerificationResults: []*ValidationResult{},
 		VerificationLevel:   &v.VerificationLevel,
@@ -301,8 +680,30 @@ func (v *dummyVerifier) Verify(ctx context.Context, desc ocispec.Descriptor, sig
 	return outcome, nil
 }
 
+func (v *dummyVerifier) SkipVerify(_ context.Context, _ VerifierVerifyOptions) (bool, *trustpolicy.VerificationLevel, error) {
+	if v.SkipVerification {
+		return true, nil, nil
+	}
+	return false, nil, nil
+}
+
+func (v *dummyVerifier) VerifyBlob(_ context.Context, _ BlobDescriptorGenerator, _ []byte, _ BlobVerifierVerifyOptions) (*VerificationOutcome, error) {
+	if v.FailVerify {
+		return nil, errors.New("failed verify")
+	}
+
+	return &VerificationOutcome{
+		VerificationResults: []*ValidationResult{},
+		VerificationLevel:   &v.VerificationLevel,
+		EnvelopeContent: &signature.EnvelopeContent{
+			Payload: signature.Payload{
+				Content: []byte("{}"),
+			},
+		},
+	}, nil
+}
+
 var (
-	ociLayoutPath     = filepath.FromSlash("./internal/testdata/oci-layout")
 	reference         = "sha256:19dbd2e48e921426ee8ace4dc892edfb2ecdc1d1a72d5416c83670c30acecef0"
 	artifactReference = "local/oci-layout@sha256:19dbd2e48e921426ee8ace4dc892edfb2ecdc1d1a72d5416c83670c30acecef0"
 	signaturePath     = filepath.FromSlash("./internal/testdata/cose_signature.sig")
@@ -310,7 +711,7 @@ var (
 
 type ociDummySigner struct{}
 
-func (s *ociDummySigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+func (s *ociDummySigner) Sign(_ context.Context, _ ocispec.Descriptor, opts SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	sigBlob, err := os.ReadFile(signaturePath)
 	if err != nil {
 		return nil, nil, err
@@ -326,37 +727,114 @@ func (s *ociDummySigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts
 	return sigBlob, &content.SignerInfo, nil
 }
 
-func TestSignLocalContent(t *testing.T) {
-	repo, err := registry.NewOCIRepository(ociLayoutPath, registry.RepositoryOptions{})
+func TestLocalContent(t *testing.T) {
+	// create a temp OCI layout
+	ociLayoutTestDataPath, err := filepath.Abs(filepath.Join("internal", "testdata", "oci-layout"))
+	if err != nil {
+		t.Fatalf("failed to get oci layout path: %v", err)
+	}
+	newOCILayoutPath := t.TempDir()
+	if err := ocilayout.Copy(ociLayoutTestDataPath, newOCILayoutPath, "v2"); err != nil {
+		t.Fatalf("failed to create temp oci layout: %v", err)
+	}
+	repo, err := registry.NewOCIRepository(newOCILayoutPath, registry.RepositoryOptions{})
 	if err != nil {
 		t.Fatal(err)
 	}
-	signOpts := SignOptions{
-		SignerSignOptions: SignerSignOptions{
-			SignatureMediaType: cose.MediaTypeEnvelope,
-		},
-		ArtifactReference: reference,
-	}
-	_, err = Sign(context.Background(), &ociDummySigner{}, repo, signOpts)
-	if err != nil {
-		t.Fatalf("failed to Sign: %v", err)
-	}
+
+	t.Run("sign the local content", func(t *testing.T) {
+		// sign the artifact
+		signOpts := SignOptions{
+			SignerSignOptions: SignerSignOptions{
+				SignatureMediaType: cose.MediaTypeEnvelope,
+			},
+			ArtifactReference: reference,
+		}
+		_, err = Sign(context.Background(), &ociDummySigner{}, repo, signOpts)
+		if err != nil {
+			t.Fatalf("failed to Sign: %v", err)
+		}
+	})
+
+	t.Run("verify local content", func(t *testing.T) {
+		// verify the artifact
+		verifyOpts := VerifyOptions{
+			ArtifactReference:    artifactReference,
+			MaxSignatureAttempts: math.MaxInt64,
+		}
+		policyDocument := dummyPolicyDocument()
+		verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict, false}
+		// verify signatures inside the OCI layout folder
+		_, _, err = Verify(context.Background(), &verifier, repo, verifyOpts)
+		if err != nil {
+			t.Fatalf("failed to verify local content: %v", err)
+		}
+	})
 }
 
-func TestVerifyLocalContent(t *testing.T) {
-	repo, err := registry.NewOCIRepository(ociLayoutPath, registry.RepositoryOptions{})
-	if err != nil {
-		t.Fatalf("failed to create oci.Store as registry.Repository: %v", err)
-	}
-	verifyOpts := VerifyOptions{
-		ArtifactReference:    artifactReference,
-		MaxSignatureAttempts: math.MaxInt64,
-	}
-	policyDocument := dummyPolicyDocument()
-	verifier := dummyVerifier{&policyDocument, mock.PluginManager{}, false, *trustpolicy.LevelStrict}
-	// verify signatures inside the OCI layout folder
-	_, _, err = Verify(context.Background(), &verifier, repo, verifyOpts)
-	if err != nil {
-		t.Fatalf("failed to verify local content: %v", err)
-	}
+func TestUserMetadata(t *testing.T) {
+	t.Run("EnvelopeContent is nil", func(t *testing.T) {
+		outcome := &VerificationOutcome{}
+		_, err := outcome.UserMetadata()
+		if err == nil {
+			t.Fatal("expected an error, got nil")
+		}
+		if err.Error() != "unable to find envelope content for verification outcome" {
+			t.Fatalf("expected error message 'unable to find envelope content for verification outcome', got '%s'", err.Error())
+		}
+	})
+
+	t.Run("EnvelopeContent is valid", func(t *testing.T) {
+		payload := envelope.Payload{
+			TargetArtifact: ocispec.Descriptor{
+				Annotations: map[string]string{
+					"key": "value",
+				},
+			},
+		}
+		payloadBytes, err := json.Marshal(payload)
+		if err != nil {
+			t.Fatalf("unexpected error marshaling payload: %v", err)
+		}
+
+		outcome := &VerificationOutcome{
+			EnvelopeContent: &signature.EnvelopeContent{
+				Payload: signature.Payload{
+					Content: payloadBytes,
+				},
+			},
+		}
+		metadata, err := outcome.UserMetadata()
+		if err != nil {
+			t.Fatalf("unexpected error getting user metadata: %v", err)
+		}
+		if len(metadata) != 1 || metadata["key"] != "value" {
+			t.Fatalf("expected metadata map[key]=value, got %v", metadata)
+		}
+	})
+
+	t.Run("Annotation is nil", func(t *testing.T) {
+		payload := envelope.Payload{
+			TargetArtifact: ocispec.Descriptor{},
+		}
+		payloadBytes, err := json.Marshal(payload)
+		if err != nil {
+			t.Fatalf("unexpected error marshaling payload: %v", err)
+		}
+
+		outcome := &VerificationOutcome{
+			EnvelopeContent: &signature.EnvelopeContent{
+				Payload: signature.Payload{
+					Content: payloadBytes,
+				},
+			},
+		}
+		metadata, err := outcome.UserMetadata()
+		if err != nil {
+			t.Fatalf("unexpected error getting user metadata: %v", err)
+		}
+		if len(metadata) != 0 {
+			t.Fatalf("expected empty metadata, got %v", metadata)
+		}
+	})
 }

plugin/errors.go

@@ -0,0 +1,96 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package plugin
+
+import "errors"
+
+// ErrNotCompliant is returned by plugin methods when the response is not
+// compliant.
+var ErrNotCompliant = errors.New("plugin not compliant")
+
+// ErrNotRegularFile is returned when the plugin file is not an regular file.
+var ErrNotRegularFile = errors.New("plugin executable file is not a regular file")
+
+// PluginDowngradeError is returned when installing a plugin with version
+// lower than the exisiting plugin version.
+type PluginDowngradeError struct {
+	Msg string
+}
+
+// Error returns the error message.
+func (e PluginDowngradeError) Error() string {
+	if e.Msg != "" {
+		return e.Msg
+	}
+	return "installing plugin with version lower than the existing plugin version"
+}
+
+// InstallEqualVersionError is returned when installing a plugin with version
+// equal to the exisiting plugin version.
+type InstallEqualVersionError struct {
+	Msg string
+}
+
+// Error returns the error message.
+func (e InstallEqualVersionError) Error() string {
+	if e.Msg != "" {
+		return e.Msg
+	}
+	return "installing plugin with version equal to the existing plugin version"
+}
+
+// PluginMalformedError is used when there is an issue with plugin and
+// should be fixed by plugin developers.
+type PluginMalformedError struct {
+	Msg        string
+	InnerError error
+}
+
+// Error returns the error message.
+func (e PluginMalformedError) Error() string {
+	if e.Msg != "" {
+		return e.Msg
+	}
+	return e.InnerError.Error()
+}
+
+// Unwrap returns the inner error.
+func (e PluginMalformedError) Unwrap() error {
+	return e.InnerError
+}
+
+// PluginDirectoryWalkError is used when there is an issue with plugins directory
+// and should suggest user to check the permission of plugin directory.
+type PluginDirectoryWalkError error
+
+// PluginExecutableFileError is used when there is an issue with plugin
+// executable file and should suggest user to check the existence, permission
+// and platform/arch compatibility of plugin.
+type PluginExecutableFileError struct {
+	Msg        string
+	InnerError error
+}
+
+// Error returns the error message.
+func (e PluginExecutableFileError) Error() string {
+	if e.Msg != "" {
+		return e.Msg
+	}
+	return e.InnerError.Error()
+}
+
+// Unwrap returns the inner error.
+func (e PluginExecutableFileError) Unwrap() error {
+	return e.InnerError
+}

plugin/integration_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package plugin
 
 import (
@@ -10,16 +23,16 @@ import (
 	"testing"
 
 	"github.com/notaryproject/notation-go/dir"
-	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 )
 
-var exampleMetadata = proto.GetMetadataResponse{
+var exampleMetadata = plugin.GetMetadataResponse{
 	Name:                      "foo",
 	Description:               "friendly",
 	Version:                   "1",
 	URL:                       "example.com",
 	SupportedContractVersions: []string{"1.0"},
-	Capabilities:              []proto.Capability{"cap"}}
+	Capabilities:              []plugin.Capability{"cap"}}
 
 func preparePlugin(t *testing.T) string {
 	root := t.TempDir()
@@ -74,11 +87,11 @@ func TestIntegration(t *testing.T) {
 	}
 
 	// validate and create
-	plugin, err := mgr.Get(context.Background(), "foo")
+	pl, err := mgr.Get(context.Background(), "foo")
 	if err != nil {
 		t.Fatal(err)
 	}
-	metadata, err := plugin.GetMetadata(context.Background(), &proto.GetMetadataRequest{})
+	metadata, err := pl.GetMetadata(context.Background(), &plugin.GetMetadataRequest{})
 	if err != nil {
 		t.Fatal(err)
 	}

plugin/manager.go

@@ -1,28 +1,41 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package plugin
 
 import (
 	"context"
 	"errors"
+	"fmt"
 	"io/fs"
+	"os"
 	"path"
+	"path/filepath"
 
 	"github.com/notaryproject/notation-go/dir"
+	"github.com/notaryproject/notation-go/internal/file"
+	"github.com/notaryproject/notation-go/internal/semver"
+	"github.com/notaryproject/notation-go/log"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 )
 
-// ErrNotCompliant is returned by plugin methods when the response is not
-// compliant.
-var ErrNotCompliant = errors.New("plugin not compliant")
-
-// ErrNotRegularFile is returned when the plugin file is not an regular file.
-var ErrNotRegularFile = errors.New("not regular file")
-
 // Manager manages plugins installed on the system.
 type Manager interface {
-	Get(ctx context.Context, name string) (Plugin, error)
+	Get(ctx context.Context, name string) (plugin.Plugin, error)
 	List(ctx context.Context) ([]string, error)
 }
 
-// CLIManager implements Manager
+// CLIManager implements [Manager]
 type CLIManager struct {
 	pluginFS dir.SysFS
 }
@@ -35,7 +48,7 @@ func NewCLIManager(pluginFS dir.SysFS) *CLIManager {
 // Get returns a plugin on the system by its name.
 //
 // If the plugin is not found, the error is of type os.ErrNotExist.
-func (m *CLIManager) Get(ctx context.Context, name string) (Plugin, error) {
+func (m *CLIManager) Get(ctx context.Context, name string) (plugin.Plugin, error) {
 	pluginPath := path.Join(name, binName(name))
 	path, err := m.pluginFS.SysPath(pluginPath)
 	if err != nil {
@@ -49,8 +62,11 @@ func (m *CLIManager) Get(ctx context.Context, name string) (Plugin, error) {
 // List produces a list of the plugin names on the system.
 func (m *CLIManager) List(ctx context.Context) ([]string, error) {
 	var plugins []string
-	fs.WalkDir(m.pluginFS, ".", func(dir string, d fs.DirEntry, err error) error {
+	if err := fs.WalkDir(m.pluginFS, ".", func(dir string, d fs.DirEntry, err error) error {
 		if err != nil {
+			if errors.Is(err, os.ErrNotExist) {
+				return nil
+			}
 			return err
 		}
 		if dir == "." {
@@ -66,6 +82,215 @@ func (m *CLIManager) List(ctx context.Context) ([]string, error) {
 		// add plugin name
 		plugins = append(plugins, d.Name())
 		return fs.SkipDir
-	})
+	}); err != nil {
+		return nil, PluginDirectoryWalkError(fmt.Errorf("failed to list plugin: %w", err))
+	}
 	return plugins, nil
 }
+
+// CLIInstallOptions provides user customized options for plugin installation
+type CLIInstallOptions struct {
+	// PluginPath can be path of:
+	//
+	// 1. A directory which contains plugin related files. Sub-directories are
+	// ignored. It MUST contain one and only one valid plugin executable file
+	// following spec: https://github.com/notaryproject/specifications/blob/v1.0.0/specs/plugin-extensibility.md#installation
+	// It may contain extra lib files and LICENSE files.
+	// On success, these files will be installed as well.
+	//
+	// 2. A single plugin executable file following the spec.
+	PluginPath string
+
+	// Overwrite is a boolean flag. When set, always install the new plugin.
+	Overwrite bool
+}
+
+// Install installs a plugin to the system. It returns existing
+// plugin metadata, new plugin metadata, and error. It returns nil error
+// if and only if the installation succeeded.
+//
+// If plugin does not exist, directly install the new plugin.
+//
+// If plugin already exists:
+//
+// If overwrite is not set, then the new plugin
+// version MUST be higher than the existing plugin version.
+//
+// If overwrite is set, version check is skipped. If existing
+// plugin is malfunctioning, it will be overwritten.
+func (m *CLIManager) Install(ctx context.Context, installOpts CLIInstallOptions) (*plugin.GetMetadataResponse, *plugin.GetMetadataResponse, error) {
+	// initialization
+	logger := log.GetLogger(ctx)
+	overwrite := installOpts.Overwrite
+	if installOpts.PluginPath == "" {
+		return nil, nil, errors.New("plugin source path cannot be empty")
+	}
+	logger.Debugf("Installing plugin from path %s", installOpts.PluginPath)
+	var installFromNonDir bool
+	pluginExecutableFile, pluginName, err := parsePluginFromDir(ctx, installOpts.PluginPath)
+	if err != nil {
+		if !errors.Is(err, file.ErrNotDirectory) {
+			return nil, nil, fmt.Errorf("failed to read plugin from input directory: %w", err)
+		}
+		// input is not a dir, check if it's a single plugin executable file
+		installFromNonDir = true
+		pluginExecutableFile = installOpts.PluginPath
+		pluginExecutableFileName := filepath.Base(pluginExecutableFile)
+		pluginName, err = parsePluginName(pluginExecutableFileName)
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to read plugin name from input file %s: %w", pluginExecutableFileName, err)
+		}
+		isExec, err := isExecutableFile(pluginExecutableFile)
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to check if input file %s is executable: %w", pluginExecutableFileName, err)
+		}
+		if !isExec {
+			return nil, nil, fmt.Errorf("input file %s is not executable", pluginExecutableFileName)
+		}
+	}
+	// validate and get new plugin metadata
+	newPlugin, err := NewCLIPlugin(ctx, pluginName, pluginExecutableFile)
+	if err != nil {
+		return nil, nil, err
+	}
+	newPluginMetadata, err := newPlugin.GetMetadata(ctx, &plugin.GetMetadataRequest{})
+	if err != nil {
+		return nil, nil, fmt.Errorf("failed to get metadata of new plugin: %w", err)
+	}
+	// check plugin existence and get existing plugin metadata
+	var existingPluginMetadata *plugin.GetMetadataResponse
+	existingPlugin, err := m.Get(ctx, pluginName)
+	if err != nil {
+		// fail only if overwrite is not set
+		if !errors.Is(err, os.ErrNotExist) && !overwrite {
+			return nil, nil, fmt.Errorf("failed to check plugin existence: %w", err)
+		}
+	} else { // plugin already exists
+		existingPluginMetadata, err = existingPlugin.GetMetadata(ctx, &plugin.GetMetadataRequest{})
+		if err != nil && !overwrite { // fail only if overwrite is not set
+			return nil, nil, fmt.Errorf("failed to get metadata of existing plugin: %w", err)
+		}
+		// existing plugin is valid, and overwrite is not set, check version
+		if !overwrite {
+			comp, err := semver.ComparePluginVersion(newPluginMetadata.Version, existingPluginMetadata.Version)
+			if err != nil {
+				return nil, nil, fmt.Errorf("failed to compare plugin versions: %w", err)
+			}
+			switch {
+			case comp < 0:
+				return nil, nil, PluginDowngradeError{Msg: fmt.Sprintf("failed to install plugin %s. The installing plugin version %s is lower than the existing plugin version %s", pluginName, newPluginMetadata.Version, existingPluginMetadata.Version)}
+			case comp == 0:
+				return nil, nil, InstallEqualVersionError{Msg: fmt.Sprintf("plugin %s with version %s already exists", pluginName, existingPluginMetadata.Version)}
+			}
+		}
+	}
+	// clean up before installation, this guarantees idempotent for install
+	if err := m.Uninstall(ctx, pluginName); err != nil {
+		if !errors.Is(err, os.ErrNotExist) {
+			return nil, nil, fmt.Errorf("failed to clean up plugin %s before installation: %w", pluginName, err)
+		}
+	}
+	// core process
+	pluginDirPath, err := m.pluginFS.SysPath(pluginName)
+	if err != nil {
+		return nil, nil, fmt.Errorf("failed to get the system path of plugin %s: %w", pluginName, err)
+	}
+	if installFromNonDir {
+		if err := file.CopyToDir(pluginExecutableFile, pluginDirPath); err != nil {
+			return nil, nil, fmt.Errorf("failed to copy plugin executable file from %s to %s: %w", pluginExecutableFile, pluginDirPath, err)
+		}
+	} else {
+		if err := file.CopyDirToDir(installOpts.PluginPath, pluginDirPath); err != nil {
+			return nil, nil, fmt.Errorf("failed to copy plugin files from %s to %s: %w", installOpts.PluginPath, pluginDirPath, err)
+		}
+	}
+	return existingPluginMetadata, newPluginMetadata, nil
+}
+
+// Uninstall uninstalls a plugin on the system by its name.
+// If the plugin dir does not exist, os.ErrNotExist is returned.
+func (m *CLIManager) Uninstall(ctx context.Context, name string) error {
+	pluginDirPath, err := m.pluginFS.SysPath(name)
+	if err != nil {
+		return err
+	}
+	if _, err := os.Stat(pluginDirPath); err != nil {
+		return err
+	}
+	return os.RemoveAll(pluginDirPath)
+}
+
+// parsePluginFromDir checks if a dir is a valid plugin dir which contains
+// one and only one plugin executable file candidate.
+// The dir may contain extra lib files and LICENSE files.
+// Sub-directories are ignored.
+//
+// On success, the plugin executable file path, plugin name and
+// nil error are returned.
+func parsePluginFromDir(ctx context.Context, path string) (string, string, error) {
+	// sanity check
+	fi, err := os.Stat(path)
+	if err != nil {
+		return "", "", err
+	}
+	if !fi.Mode().IsDir() {
+		return "", "", file.ErrNotDirectory
+	}
+	logger := log.GetLogger(ctx)
+	// walk the path
+	var pluginExecutableFile, pluginName, candidatePluginName string
+	var foundPluginExecutableFile bool
+	var filesWithValidNameFormat []string
+	if err := filepath.WalkDir(path, func(p string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		// skip sub-directories
+		if d.IsDir() && d.Name() != filepath.Base(path) {
+			return fs.SkipDir
+		}
+		info, err := d.Info()
+		if err != nil {
+			return err
+		}
+		// only take regular files
+		if info.Mode().IsRegular() {
+			if candidatePluginName, err = parsePluginName(d.Name()); err != nil {
+				// file name does not follow the notation-{plugin-name} format,
+				// continue
+				return nil
+			}
+			filesWithValidNameFormat = append(filesWithValidNameFormat, p)
+			isExec, err := isExecutableFile(p)
+			if err != nil {
+				return err
+			}
+			if !isExec {
+				return nil
+			}
+			if foundPluginExecutableFile {
+				return errors.New("found more than one plugin executable files")
+			}
+			foundPluginExecutableFile = true
+			pluginExecutableFile = p
+			pluginName = candidatePluginName
+		}
+		return nil
+	}); err != nil {
+		return "", "", err
+	}
+	if !foundPluginExecutableFile {
+		// if no executable file was found, but there's one and only one
+		// potential candidate, try install the candidate
+		if len(filesWithValidNameFormat) == 1 {
+			candidate := filesWithValidNameFormat[0]
+			if err := setExecutable(candidate); err != nil {
+				return "", "", fmt.Errorf("no plugin executable file was found: %w", err)
+			}
+			logger.Warnf("Found candidate plugin executable file %q without executable permission. Setting user executable bit and trying to install.", filepath.Base(candidate))
+			return candidate, candidatePluginName, nil
+		}
+		return "", "", errors.New("no plugin executable file was found")
+	}
+	return pluginExecutableFile, pluginName, nil
+}

plugin/manager_test.go

@@ -1,10 +1,26 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package plugin
 
 import (
 	"context"
 	"encoding/json"
 	"io/fs"
+	"os"
+	"path/filepath"
 	"reflect"
+	"runtime"
 	"testing"
 	"testing/fstest"
 
@@ -22,8 +38,50 @@ func (t testCommander) Output(ctx context.Context, path string, command proto.Co
 	return t.stdout, t.stderr, t.err
 }
 
+type testInstallCommander struct {
+	existedPluginFilePath string
+	existedPluginStdout   []byte
+	existedPluginStderr   []byte
+	existedPluginErr      error
+	newPluginFilePath     string
+	newPluginStdout       []byte
+	newPluginStderr       []byte
+	newPluginErr          error
+	err                   error
+}
+
+func (t testInstallCommander) Output(ctx context.Context, path string, command proto.Command, req []byte) ([]byte, []byte, error) {
+	if path == t.existedPluginFilePath {
+		return t.existedPluginStdout, t.existedPluginStderr, t.existedPluginErr
+	}
+	if path == t.newPluginFilePath {
+		return t.newPluginStdout, t.newPluginStderr, t.newPluginErr
+	}
+	return nil, nil, t.err
+}
+
 var validMetadata = proto.GetMetadataResponse{
-	Name: "foo", Description: "friendly", Version: "1", URL: "example.com",
+	Name: "foo", Description: "friendly", Version: "1.0.0", URL: "example.com",
+	SupportedContractVersions: []string{"1.0"}, Capabilities: []proto.Capability{proto.CapabilitySignatureGenerator},
+}
+
+var validMetadataHigherVersion = proto.GetMetadataResponse{
+	Name: "foo", Description: "friendly", Version: "1.1.0", URL: "example.com",
+	SupportedContractVersions: []string{"1.0"}, Capabilities: []proto.Capability{proto.CapabilitySignatureGenerator},
+}
+
+var validMetadataLowerVersion = proto.GetMetadataResponse{
+	Name: "foo", Description: "friendly", Version: "0.1.0", URL: "example.com",
+	SupportedContractVersions: []string{"1.0"}, Capabilities: []proto.Capability{proto.CapabilitySignatureGenerator},
+}
+
+var validMetadataBar = proto.GetMetadataResponse{
+	Name: "bar", Description: "friendly", Version: "1.0.0", URL: "example.com",
+	SupportedContractVersions: []string{"1.0"}, Capabilities: []proto.Capability{proto.CapabilitySignatureGenerator},
+}
+
+var validMetadataBarExample = proto.GetMetadataResponse{
+	Name: "bar.example.plugin", Description: "friendly", Version: "1.0.0", URL: "example.com",
 	SupportedContractVersions: []string{"1.0"}, Capabilities: []proto.Capability{proto.CapabilitySignatureGenerator},
 }
 
@@ -38,6 +96,9 @@ var invalidContractVersionMetadata = proto.GetMetadataResponse{
 }
 
 func TestManager_Get(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping test on Windows")
+	}
 	executor = testCommander{stdout: metadataJSON(validMetadata)}
 	mgr := NewCLIManager(mockfs.NewSysFSWithRootMock(fstest.MapFS{}, "./testdata/plugins"))
 	_, err := mgr.Get(context.Background(), "foo")
@@ -74,6 +135,533 @@ func TestManager_List(t *testing.T) {
 	})
 }
 
+func TestManager_Install(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping test on Windows")
+	}
+	existedPluginFilePath := "testdata/plugins/foo/notation-foo"
+	newPluginFilePath := "testdata/foo/notation-foo"
+	newPluginDir := filepath.Dir(newPluginFilePath)
+	if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+		t.Fatalf("failed to create %s: %v", newPluginDir, err)
+	}
+	defer os.RemoveAll(newPluginDir)
+	if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+		t.Fatal(err)
+	}
+	mgr := NewCLIManager(mockfs.NewSysFSWithRootMock(fstest.MapFS{}, "testdata/plugins"))
+
+	t.Run("success install with higher version", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataHigherVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		existingPluginMetadata, newPluginMetadata, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting error to be nil, but got %v", err)
+		}
+		if existingPluginMetadata.Version != validMetadata.Version {
+			t.Fatalf("existing plugin version mismatch, existing plugin version: %s, but got: %s", validMetadata.Version, existingPluginMetadata.Version)
+		}
+		if newPluginMetadata.Version != validMetadataHigherVersion.Version {
+			t.Fatalf("new plugin version mismatch, new plugin version: %s, but got: %s", validMetadataHigherVersion.Version, newPluginMetadata.Version)
+		}
+	})
+
+	t.Run("success install with lower version and overwrite", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataLowerVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+			Overwrite:  true,
+		}
+		if _, _, err := mgr.Install(context.Background(), installOpts); err != nil {
+			t.Fatalf("expecting error to be nil, but got %v", err)
+		}
+	})
+
+	t.Run("success install without existing plugin", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-bar"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBar),
+		}
+		defer mgr.Uninstall(context.Background(), "bar")
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		existingPluginMetadata, newPluginMetadata, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting error to be nil, but got %v", err)
+		}
+		if existingPluginMetadata != nil {
+			t.Fatalf("expecting existingPluginMetadata to be nil, but got %v", existingPluginMetadata)
+		}
+		if newPluginMetadata.Version != validMetadataBar.Version {
+			t.Fatalf("new plugin version mismatch, new plugin version: %s, but got: %s", validMetadataBar.Version, newPluginMetadata.Version)
+		}
+	})
+
+	t.Run("success install with file extension", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-bar.example.plugin"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBarExample),
+		}
+		defer mgr.Uninstall(context.Background(), "bar.example.plugin")
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		existingPluginMetadata, newPluginMetadata, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting error to be nil, but got %v", err)
+		}
+		if existingPluginMetadata != nil {
+			t.Fatalf("expecting existingPluginMetadata to be nil, but got %v", existingPluginMetadata)
+		}
+		if newPluginMetadata.Version != validMetadataBar.Version {
+			t.Fatalf("new plugin version mismatch, new plugin version: %s, but got: %s", validMetadataBar.Version, newPluginMetadata.Version)
+		}
+	})
+
+	t.Run("fail to install due to equal version", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadata),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "plugin foo with version 1.0.0 already exists"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to lower version", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataLowerVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to install plugin foo. The installing plugin version 0.1.0 is lower than the existing plugin version 1.0.0"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to wrong plugin executable file name format", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/bar"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBar),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to read plugin name from input file bar: invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got bar"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to plugin executable file name missing plugin name", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBar),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to read plugin name from input file notation-: invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got notation-"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to wrong plugin file permission", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-bar"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0600); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBar),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "input file notation-bar is not executable"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to new plugin executable file does not exist", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-bar"
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(validMetadataBar),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to read plugin from input directory: stat testdata/bar/notation-bar: no such file or directory"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to invalid new plugin metadata", func(t *testing.T) {
+		newPluginFilePath := "testdata/bar/notation-bar"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			newPluginFilePath: newPluginFilePath,
+			newPluginStdout:   metadataJSON(invalidMetadataName),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to get metadata of new plugin: plugin executable file name must be \"notation-foobar\" instead of \"notation-bar\""
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install due to invalid existing plugin metadata", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadataBar),
+			newPluginStdout:       metadataJSON(validMetadata),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+		}
+		expectedErrorMsg := "failed to get metadata of existing plugin: plugin executable file name must be \"notation-bar\" instead of \"notation-foo\""
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("success to install with overwrite and invalid existing plugin metadata", func(t *testing.T) {
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadataBar),
+			newPluginStdout:       metadataJSON(validMetadata),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginFilePath,
+			Overwrite:  true,
+		}
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting error to be nil, but got %v", err)
+		}
+	})
+
+	t.Run("success to install from plugin dir", func(t *testing.T) {
+		existedPluginFilePath := "testdata/plugins/foo/notation-foo"
+		newPluginFilePath := "testdata/foo/notation-foo"
+		newPluginLibPath := "testdata/foo/notation-libfoo"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := createFileAndChmod(newPluginLibPath, 0600); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataHigherVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginDir,
+		}
+		existingPluginMetadata, newPluginMetadata, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting nil error, but got %v", err)
+		}
+		if existingPluginMetadata.Version != "1.0.0" {
+			t.Fatalf("expecting existing plugin metadata to be 1.0.0, but got %s", existingPluginMetadata.Version)
+		}
+		if newPluginMetadata.Version != "1.1.0" {
+			t.Fatalf("expecting new plugin metadata to be 1.1.0, but got %s", newPluginMetadata.Version)
+		}
+	})
+
+	t.Run("success to install from plugin dir with no executable file and one valid candidate file", func(t *testing.T) {
+		existedPluginFilePath := "testdata/plugins/foo/notation-foo"
+		newPluginFilePath := "testdata/foo/notation-foo"
+		newPluginLibPath := "testdata/foo/libfoo"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0600); err != nil {
+			t.Fatal(err)
+		}
+		if err := createFileAndChmod(newPluginLibPath, 0600); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataHigherVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginDir,
+		}
+		existingPluginMetadata, newPluginMetadata, err := mgr.Install(context.Background(), installOpts)
+		if err != nil {
+			t.Fatalf("expecting nil error, but got %v", err)
+		}
+		if existingPluginMetadata.Version != "1.0.0" {
+			t.Fatalf("expecting existing plugin metadata to be 1.0.0, but got %s", existingPluginMetadata.Version)
+		}
+		if newPluginMetadata.Version != "1.1.0" {
+			t.Fatalf("expecting new plugin metadata to be 1.1.0, but got %s", newPluginMetadata.Version)
+		}
+	})
+
+	t.Run("fail to install from plugin dir due to more than one candidate plugin executable files", func(t *testing.T) {
+		existedPluginFilePath := "testdata/plugins/foo/notation-foo"
+		newPluginFilePath := "testdata/foo/notation-foo1"
+		newPluginFilePath2 := "testdata/foo/notation-foo2"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0600); err != nil {
+			t.Fatal(err)
+		}
+		if err := createFileAndChmod(newPluginFilePath2, 0600); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataHigherVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginDir,
+		}
+		expectedErrorMsg := "failed to read plugin from input directory: no plugin executable file was found"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+
+	t.Run("fail to install from plugin dir due to more than one plugin executable files", func(t *testing.T) {
+		existedPluginFilePath := "testdata/plugins/foo/notation-foo"
+		newPluginFilePath := "testdata/foo/notation-foo1"
+		newPluginFilePath2 := "testdata/foo/notation-foo2"
+		newPluginDir := filepath.Dir(newPluginFilePath)
+		if err := os.MkdirAll(newPluginDir, 0777); err != nil {
+			t.Fatalf("failed to create %s: %v", newPluginDir, err)
+		}
+		defer os.RemoveAll(newPluginDir)
+		if err := createFileAndChmod(newPluginFilePath, 0700); err != nil {
+			t.Fatal(err)
+		}
+		if err := createFileAndChmod(newPluginFilePath2, 0700); err != nil {
+			t.Fatal(err)
+		}
+		executor = testInstallCommander{
+			existedPluginFilePath: existedPluginFilePath,
+			newPluginFilePath:     newPluginFilePath,
+			existedPluginStdout:   metadataJSON(validMetadata),
+			newPluginStdout:       metadataJSON(validMetadataHigherVersion),
+		}
+		installOpts := CLIInstallOptions{
+			PluginPath: newPluginDir,
+		}
+		expectedErrorMsg := "failed to read plugin from input directory: found more than one plugin executable files"
+		_, _, err := mgr.Install(context.Background(), installOpts)
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expecting error %s, but got %v", expectedErrorMsg, err)
+		}
+	})
+}
+
+func TestManager_Uninstall(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping test on Windows")
+	}
+	executor = testCommander{stdout: metadataJSON(validMetadata)}
+	mgr := NewCLIManager(mockfs.NewSysFSWithRootMock(fstest.MapFS{}, "./testdata/plugins"))
+	if err := os.MkdirAll("./testdata/plugins/toUninstall", 0777); err != nil {
+		t.Fatalf("failed to create toUninstall dir: %v", err)
+	}
+	defer os.RemoveAll("./testdata/plugins/toUninstall")
+	pluginFile, err := os.Create("./testdata/plugins/toUninstall/toUninstall")
+	if err != nil {
+		t.Fatalf("failed to create toUninstall file: %v", err)
+	}
+	if err := pluginFile.Close(); err != nil {
+		t.Fatalf("failed to close toUninstall file: %v", err)
+	}
+	// test uninstall valid plugin
+	if err := mgr.Uninstall(context.Background(), "toUninstall"); err != nil {
+		t.Fatalf("Manager.Uninstall() err %v, want nil", err)
+	}
+	// test uninstall non-exist plugin
+	expectedErrorMsg := "stat testdata/plugins/non-exist: no such file or directory"
+	if err := mgr.Uninstall(context.Background(), "non-exist"); err == nil || err.Error() != expectedErrorMsg {
+		t.Fatalf("Manager.Uninstall() err %v, want %s", err, expectedErrorMsg)
+	}
+}
+
+func TestParsePluginName(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		pluginName, err := parsePluginName("notation-my-plugin.exe")
+		if err != nil {
+			t.Fatalf("expected nil err, but got %v", err)
+		}
+		if pluginName != "my-plugin" {
+			t.Fatalf("expected plugin name my-plugin, but got %s", pluginName)
+		}
+
+		expectedErrorMsg := "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got notation-com.plugin"
+		_, err = parsePluginName("notation-com.plugin")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+
+		expectedErrorMsg = "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got my-plugin.exe"
+		_, err = parsePluginName("my-plugin.exe")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+
+		expectedErrorMsg = "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got notation-.exe"
+		_, err = parsePluginName("notation-.exe")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+
+		expectedErrorMsg = "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got my-plugin"
+		_, err = parsePluginName("my-plugin")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+	} else {
+		pluginName, err := parsePluginName("notation-my-plugin")
+		if err != nil {
+			t.Fatalf("expected nil err, but got %v", err)
+		}
+		if pluginName != "my-plugin" {
+			t.Fatalf("expected plugin name my-plugin, but got %s", pluginName)
+		}
+
+		pluginName, err = parsePluginName("notation-com.example.plugin")
+		if err != nil {
+			t.Fatalf("expected nil err, but got %v", err)
+		}
+		if pluginName != "com.example.plugin" {
+			t.Fatalf("expected plugin name com.example.plugin, but got %s", pluginName)
+		}
+
+		expectedErrorMsg := "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got myPlugin"
+		_, err = parsePluginName("myPlugin")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+
+		expectedErrorMsg = "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got my-plugin"
+		_, err = parsePluginName("my-plugin")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+
+		expectedErrorMsg = "invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got notation-"
+		_, err = parsePluginName("notation-")
+		if err == nil || err.Error() != expectedErrorMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrorMsg, err)
+		}
+	}
+}
+
 func metadataJSON(m proto.GetMetadataResponse) []byte {
 	d, err := json.Marshal(m)
 	if err != nil {
@@ -81,3 +669,14 @@ func metadataJSON(m proto.GetMetadataResponse) []byte {
 	}
 	return d
 }
+
+func createFileAndChmod(path string, mode fs.FileMode) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	if err := f.Chmod(mode); err != nil {
+		return err
+	}
+	return f.Close()
+}

plugin/manager_unix.go

@@ -1,10 +1,61 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 //go:build !windows
 // +build !windows
 
 package plugin
 
-import "github.com/notaryproject/notation-go/plugin/proto"
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
+)
 
 func binName(name string) string {
-	return proto.Prefix + name
+	return plugin.BinaryPrefix + name
+}
+
+// isExecutableFile checks if a file at filePath is user executable
+func isExecutableFile(filePath string) (bool, error) {
+	fi, err := os.Stat(filePath)
+	if err != nil {
+		return false, err
+	}
+	mode := fi.Mode()
+	if !mode.IsRegular() {
+		return false, ErrNotRegularFile
+	}
+	return mode.Perm()&0100 != 0, nil
+}
+
+// parsePluginName checks if fileName is a valid plugin file name
+// and gets plugin name from it based on spec: https://github.com/notaryproject/specifications/blob/main/specs/plugin-extensibility.md#installation
+func parsePluginName(fileName string) (string, error) {
+	pluginName, found := strings.CutPrefix(fileName, plugin.BinaryPrefix)
+	if !found || pluginName == "" {
+		return "", fmt.Errorf("invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}, but got %s", fileName)
+	}
+	return pluginName, nil
+}
+
+// setExecutable sets file to be user executable
+func setExecutable(filePath string) error {
+	fileInfo, err := os.Stat(filePath)
+	if err != nil {
+		return err
+	}
+	return os.Chmod(filePath, fileInfo.Mode()|os.FileMode(0100))
 }

plugin/manager_windows.go

@@ -1,7 +1,60 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package plugin
 
-import "github.com/notaryproject/notation-go/plugin/proto"
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/notaryproject/notation-go/internal/file"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
+)
 
 func binName(name string) string {
-	return proto.Prefix + name + ".exe"
+	return plugin.BinaryPrefix + name + ".exe"
+}
+
+// isExecutableFile checks if a file at filePath is executable
+func isExecutableFile(filePath string) (bool, error) {
+	fi, err := os.Stat(filePath)
+	if err != nil {
+		return false, err
+	}
+	if !fi.Mode().IsRegular() {
+		return false, ErrNotRegularFile
+	}
+	return strings.EqualFold(filepath.Ext(filepath.Base(filePath)), ".exe"), nil
+}
+
+// parsePluginName checks if fileName is a valid plugin file name
+// and gets plugin name from it based on spec: https://github.com/notaryproject/specifications/blob/main/specs/plugin-extensibility.md#installation
+func parsePluginName(fileName string) (string, error) {
+	if !strings.EqualFold(filepath.Ext(fileName), ".exe") {
+		return "", fmt.Errorf("invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got %s", fileName)
+	}
+	fname := file.TrimFileExtension(fileName)
+	pluginName, found := strings.CutPrefix(fname, plugin.BinaryPrefix)
+	if !found || pluginName == "" {
+		return "", fmt.Errorf("invalid plugin executable file name. Plugin file name requires format notation-{plugin-name}.exe, but got %s", fileName)
+	}
+	return pluginName, nil
+}
+
+// setExecutable returns error on Windows. User needs to install the correct
+// plugin file.
+func setExecutable(filePath string) error {
+	return fmt.Errorf(`plugin executable file must have file extension ".exe", but got %q`, filepath.Base(filePath))
 }

plugin/plugin.go

@@ -1,4 +1,17 @@
-// Package plugin provides the toolings to use the notation plugin.
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package plugin provides the tooling to use the notation plugin.
 //
 // includes a CLIManager and a CLIPlugin implementation.
 package plugin
@@ -12,63 +25,58 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strings"
 
+	"github.com/notaryproject/notation-go/internal/io"
 	"github.com/notaryproject/notation-go/internal/slices"
 	"github.com/notaryproject/notation-go/log"
 	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 )
 
+// maxPluginOutputSize is the maximum size of the plugin output.
+const maxPluginOutputSize = 64 * 1024 * 1024 // 64 MiB
+
 var executor commander = &execCommander{} // for unit test
 
-// GenericPlugin is the base requirement to be an plugin.
-type GenericPlugin interface {
-	// GetMetadata returns the metadata information of the plugin.
-	GetMetadata(ctx context.Context, req *proto.GetMetadataRequest) (*proto.GetMetadataResponse, error)
-}
+// GenericPlugin is the base requirement to be a plugin.
+//
+// Deprecated: GenericPlugin exists for historical compatibility and should not be used.
+// To access GenericPlugin, use the notation-plugin-framework-go's plugin.GenericPlugin type.
+type GenericPlugin = plugin.GenericPlugin
 
 // SignPlugin defines the required methods to be a SignPlugin.
-type SignPlugin interface {
-	GenericPlugin
-
-	// DescribeKey returns the KeySpec of a key.
-	DescribeKey(ctx context.Context, req *proto.DescribeKeyRequest) (*proto.DescribeKeyResponse, error)
-
-	// GenerateSignature generates the raw signature based on the request.
-	GenerateSignature(ctx context.Context, req *proto.GenerateSignatureRequest) (*proto.GenerateSignatureResponse, error)
-
-	// GenerateEnvelope generates the Envelope with signature based on the
-	// request.
-	GenerateEnvelope(ctx context.Context, req *proto.GenerateEnvelopeRequest) (*proto.GenerateEnvelopeResponse, error)
-}
+//
+// Deprecated: SignPlugin exists for historical compatibility and should not be used.
+// To access SignPlugin, use the notation-plugin-framework-go's plugin.SignPlugin type.
+type SignPlugin = plugin.SignPlugin
 
 // VerifyPlugin defines the required method to be a VerifyPlugin.
-type VerifyPlugin interface {
-	GenericPlugin
+//
+// Deprecated: VerifyPlugin exists for historical compatibility and should not be used.
+// To access VerifyPlugin, use the notation-plugin-framework-go's plugin.VerifyPlugin type.
+type VerifyPlugin = plugin.VerifyPlugin
 
-	// VerifySignature validates the signature based on the request.
-	VerifySignature(ctx context.Context, req *proto.VerifySignatureRequest) (*proto.VerifySignatureResponse, error)
-}
+// Plugin defines required methods to be a Plugin.
+//
+// Deprecated: Plugin exists for historical compatibility and should not be used.
+// To access Plugin, use the notation-plugin-framework-go's plugin.Plugin type.
+type Plugin = plugin.Plugin
 
-// Plugin defines required methods to be an Plugin.
-type Plugin interface {
-	SignPlugin
-	VerifyPlugin
-}
-
-// CLIPlugin implements Plugin interface to CLI plugins.
+// CLIPlugin implements [Plugin] interface to CLI plugins.
 type CLIPlugin struct {
 	name string
 	path string
 }
 
-// NewCLIPlugin validate the metadata of the plugin and return a *CLIPlugin.
+// NewCLIPlugin returns a *CLIPlugin.
 func NewCLIPlugin(ctx context.Context, name, path string) (*CLIPlugin, error) {
 	// validate file existence
 	fi, err := os.Stat(path)
 	if err != nil {
 		// Ignore any file which we cannot Stat
 		// (e.g. due to permissions or anything else).
-		return nil, err
+		return nil, fmt.Errorf("plugin executable file is either not found or inaccessible: %w", err)
 	}
 	if !fi.Mode().IsRegular() {
 		// Ignore non-regular files.
@@ -76,26 +84,28 @@ func NewCLIPlugin(ctx context.Context, name, path string) (*CLIPlugin, error) {
 	}
 
 	// generate plugin
-	plugin := CLIPlugin{
+	return &CLIPlugin{
 		name: name,
 		path: path,
-	}
-	return &plugin, nil
+	}, nil
 }
 
 // GetMetadata returns the metadata information of the plugin.
-func (p *CLIPlugin) GetMetadata(ctx context.Context, req *proto.GetMetadataRequest) (*proto.GetMetadataResponse, error) {
-	var metadata proto.GetMetadataResponse
+func (p *CLIPlugin) GetMetadata(ctx context.Context, req *plugin.GetMetadataRequest) (*plugin.GetMetadataResponse, error) {
+	var metadata plugin.GetMetadataResponse
 	err := run(ctx, p.name, p.path, req, &metadata)
 	if err != nil {
 		return nil, err
 	}
 	// validate metadata
 	if err = validate(&metadata); err != nil {
-		return nil, fmt.Errorf("invalid metadata: %w", err)
+		return nil, &PluginMalformedError{
+			Msg:        fmt.Sprintf("metadata validation failed for plugin %s: %s", p.name, err),
+			InnerError: err,
+		}
 	}
 	if metadata.Name != p.name {
-		return nil, fmt.Errorf("executable name must be %q instead of %q", binName(metadata.Name), filepath.Base(p.path))
+		return nil, fmt.Errorf("plugin executable file name must be %q instead of %q", binName(metadata.Name), filepath.Base(p.path))
 	}
 	return &metadata, nil
 }
@@ -103,12 +113,12 @@ func (p *CLIPlugin) GetMetadata(ctx context.Context, req *proto.GetMetadataReque
 // DescribeKey returns the KeySpec of a key.
 //
 // if ContractVersion is not set, it will be set by the function.
-func (p *CLIPlugin) DescribeKey(ctx context.Context, req *proto.DescribeKeyRequest) (*proto.DescribeKeyResponse, error) {
+func (p *CLIPlugin) DescribeKey(ctx context.Context, req *plugin.DescribeKeyRequest) (*plugin.DescribeKeyResponse, error) {
 	if req.ContractVersion == "" {
-		req.ContractVersion = proto.ContractVersion
+		req.ContractVersion = plugin.ContractVersion
 	}
 
-	var resp proto.DescribeKeyResponse
+	var resp plugin.DescribeKeyResponse
 	err := run(ctx, p.name, p.path, req, &resp)
 	return &resp, err
 }
@@ -116,12 +126,12 @@ func (p *CLIPlugin) DescribeKey(ctx context.Context, req *proto.DescribeKeyReque
 // GenerateSignature generates the raw signature based on the request.
 //
 // if ContractVersion is not set, it will be set by the function.
-func (p *CLIPlugin) GenerateSignature(ctx context.Context, req *proto.GenerateSignatureRequest) (*proto.GenerateSignatureResponse, error) {
+func (p *CLIPlugin) GenerateSignature(ctx context.Context, req *plugin.GenerateSignatureRequest) (*plugin.GenerateSignatureResponse, error) {
 	if req.ContractVersion == "" {
-		req.ContractVersion = proto.ContractVersion
+		req.ContractVersion = plugin.ContractVersion
 	}
 
-	var resp proto.GenerateSignatureResponse
+	var resp plugin.GenerateSignatureResponse
 	err := run(ctx, p.name, p.path, req, &resp)
 	return &resp, err
 }
@@ -129,12 +139,12 @@ func (p *CLIPlugin) GenerateSignature(ctx context.Context, req *proto.GenerateSi
 // GenerateEnvelope generates the Envelope with signature based on the request.
 //
 // if ContractVersion is not set, it will be set by the function.
-func (p *CLIPlugin) GenerateEnvelope(ctx context.Context, req *proto.GenerateEnvelopeRequest) (*proto.GenerateEnvelopeResponse, error) {
+func (p *CLIPlugin) GenerateEnvelope(ctx context.Context, req *plugin.GenerateEnvelopeRequest) (*plugin.GenerateEnvelopeResponse, error) {
 	if req.ContractVersion == "" {
-		req.ContractVersion = proto.ContractVersion
+		req.ContractVersion = plugin.ContractVersion
 	}
 
-	var resp proto.GenerateEnvelopeResponse
+	var resp plugin.GenerateEnvelopeResponse
 	err := run(ctx, p.name, p.path, req, &resp)
 	return &resp, err
 }
@@ -142,76 +152,96 @@ func (p *CLIPlugin) GenerateEnvelope(ctx context.Context, req *proto.GenerateEnv
 // VerifySignature validates the signature based on the request.
 //
 // if ContractVersion is not set, it will be set by the function.
-func (p *CLIPlugin) VerifySignature(ctx context.Context, req *proto.VerifySignatureRequest) (*proto.VerifySignatureResponse, error) {
+func (p *CLIPlugin) VerifySignature(ctx context.Context, req *plugin.VerifySignatureRequest) (*plugin.VerifySignatureResponse, error) {
 	if req.ContractVersion == "" {
-		req.ContractVersion = proto.ContractVersion
+		req.ContractVersion = plugin.ContractVersion
 	}
 
-	var resp proto.VerifySignatureResponse
+	var resp plugin.VerifySignatureResponse
 	err := run(ctx, p.name, p.path, req, &resp)
 	return &resp, err
 }
 
-func run(ctx context.Context, pluginName string, pluginPath string, req proto.Request, resp interface{}) error {
+func run(ctx context.Context, pluginName string, pluginPath string, req plugin.Request, resp interface{}) error {
 	logger := log.GetLogger(ctx)
 
 	// serialize request
 	data, err := json.Marshal(req)
 	if err != nil {
-		return fmt.Errorf("%s: failed to marshal request object: %w", pluginName, err)
+		logger.Errorf("Failed to marshal request object: %+v", req)
+		return fmt.Errorf("failed to marshal request object: %w", err)
 	}
 
 	logger.Debugf("Plugin %s request: %s", req.Command(), string(data))
 	// execute request
 	stdout, stderr, err := executor.Output(ctx, pluginPath, req.Command(), data)
 	if err != nil {
-		logger.Debugf("plugin %s execution status: %v", req.Command(), err)
-		logger.Debugf("Plugin %s returned error: %s", req.Command(), string(stderr))
-		var re proto.RequestError
-		jsonErr := json.Unmarshal(stderr, &re)
-		if jsonErr != nil {
-			return proto.RequestError{
-				Code: proto.ErrorCodeGeneric,
-				Err:  fmt.Errorf("response is not in JSON format. error: %v, stderr: %s", err, string(stderr))}
+		logger.Errorf("plugin %s execution status: %v", req.Command(), err)
+
+		if len(stderr) == 0 {
+			// if stderr is empty, it is possible that the plugin is not
+			// running properly.
+			logger.Errorf("failed to execute the %s command for plugin %s: %s", req.Command(), pluginName, err)
+			return &PluginExecutableFileError{
+				InnerError: err,
+			}
+		} else {
+			var re proto.RequestError
+			jsonErr := json.Unmarshal(stderr, &re)
+			if jsonErr != nil {
+				logger.Errorf("failed to execute the %s command for plugin %s: %s", req.Command(), pluginName, strings.TrimSuffix(string(stderr), "\n"))
+				return &PluginMalformedError{
+					InnerError: jsonErr,
+				}
+			}
+			logger.Errorf("failed to execute the %s command for plugin %s: %s: %w", req.Command(), pluginName, re.Code, re)
+			return re
 		}
-		return re
 	}
 
 	logger.Debugf("Plugin %s response: %s", req.Command(), string(stdout))
 	// deserialize response
-	err = json.Unmarshal(stdout, resp)
-	if err != nil {
-		return fmt.Errorf("failed to decode json response: %w", ErrNotCompliant)
+	if err = json.Unmarshal(stdout, resp); err != nil {
+		logger.Errorf("failed to unmarshal plugin %s response: %w", req.Command(), err)
+		return &PluginMalformedError{
+			Msg:        fmt.Sprintf("failed to unmarshal the response of %s command for plugin %s", req.Command(), pluginName),
+			InnerError: err,
+		}
 	}
 	return nil
 }
 
 // commander is defined for mocking purposes.
 type commander interface {
-	// Output runs the command, passing req to the its stdin.
+	// Output runs the command, passing req to the stdin.
 	// It only returns an error if the binary can't be executed.
 	// Returns stdout if err is nil, stderr if err is not nil.
-	Output(ctx context.Context, path string, command proto.Command, req []byte) (stdout []byte, stderr []byte, err error)
+	Output(ctx context.Context, path string, command plugin.Command, req []byte) (stdout []byte, stderr []byte, err error)
 }
 
 // execCommander implements the commander interface using exec.Command().
 type execCommander struct{}
 
-func (c execCommander) Output(ctx context.Context, name string, command proto.Command, req []byte) ([]byte, []byte, error) {
+func (c execCommander) Output(ctx context.Context, name string, command plugin.Command, req []byte) ([]byte, []byte, error) {
 	var stdout, stderr bytes.Buffer
 	cmd := exec.CommandContext(ctx, name, string(command))
 	cmd.Stdin = bytes.NewReader(req)
-	cmd.Stderr = &stderr
-	cmd.Stdout = &stdout
+	// The limit writer will be handled by the caller in run() by comparing the
+	// bytes written with the expected length of the bytes.
+	cmd.Stderr = io.LimitWriter(&stderr, maxPluginOutputSize)
+	cmd.Stdout = io.LimitWriter(&stdout, maxPluginOutputSize)
 	err := cmd.Run()
 	if err != nil {
+		if errors.Is(ctx.Err(), context.DeadlineExceeded) {
+			return nil, stderr.Bytes(), fmt.Errorf("'%s %s' command execution timeout: %w", name, string(command), err)
+		}
 		return nil, stderr.Bytes(), err
 	}
 	return stdout.Bytes(), nil, nil
 }
 
 // validate checks if the metadata is correctly populated.
-func validate(metadata *proto.GetMetadataResponse) error {
+func validate(metadata *plugin.GetMetadataResponse) error {
 	if metadata.Name == "" {
 		return errors.New("empty name")
 	}
@@ -230,10 +260,10 @@ func validate(metadata *proto.GetMetadataResponse) error {
 	if len(metadata.SupportedContractVersions) == 0 {
 		return errors.New("supported contract versions not specified")
 	}
-	if !slices.Contains(metadata.SupportedContractVersions, proto.ContractVersion) {
+	if !slices.Contains(metadata.SupportedContractVersions, plugin.ContractVersion) {
 		return fmt.Errorf(
 			"contract version %q is not in the list of the plugin supported versions %v",
-			proto.ContractVersion, metadata.SupportedContractVersions,
+			plugin.ContractVersion, metadata.SupportedContractVersions,
 		)
 	}
 	return nil

plugin/plugin_test.go

@@ -1,15 +1,29 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package plugin
 
 import (
 	"context"
 	"encoding/json"
 	"errors"
-	"fmt"
 	"os"
 	"reflect"
+	"runtime"
 	"strconv"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/notaryproject/notation-go/plugin/proto"
 )
@@ -18,14 +32,12 @@ func TestGetMetadata(t *testing.T) {
 	t.Run("plugin error is in invalid json format", func(t *testing.T) {
 		exitErr := errors.New("unknown error")
 		stderr := []byte("sad")
-		wantErr := proto.RequestError{
-			Code: proto.ErrorCodeGeneric,
-			Err:  fmt.Errorf("response is not in JSON format. error: %v, stderr: %s", exitErr, string(stderr))}
-		plugin := CLIPlugin{}
+		expectedErrMsg := "invalid character 's' looking for beginning of value"
+		plugin := CLIPlugin{name: "test-plugin"}
 		executor = testCommander{stdout: nil, stderr: stderr, err: exitErr}
 		_, err := plugin.GetMetadata(context.Background(), &proto.GetMetadataRequest{})
-		if !errors.Is(err, wantErr) {
-			t.Fatalf("should error. got err = %v, want %v", err, wantErr)
+		if err.Error() != expectedErrMsg {
+			t.Fatalf("should error. got err = %v, want %v", err, expectedErrMsg)
 		}
 	})
 
@@ -45,14 +57,12 @@ func TestGetMetadata(t *testing.T) {
 	t.Run("plugin cause system error", func(t *testing.T) {
 		exitErr := errors.New("system error")
 		stderr := []byte("")
-		wantErr := proto.RequestError{
-			Code: proto.ErrorCodeGeneric,
-			Err:  fmt.Errorf("response is not in JSON format. error: %v, stderr: %s", exitErr, string(stderr))}
-		plugin := CLIPlugin{}
+		expectedErrMsg := "system error"
+		plugin := CLIPlugin{name: "test-plugin"}
 		executor = testCommander{stdout: nil, stderr: stderr, err: exitErr}
 		_, err := plugin.GetMetadata(context.Background(), &proto.GetMetadataRequest{})
-		if !errors.Is(err, wantErr) {
-			t.Fatalf("should error. got err = %v, want %v", err, wantErr)
+		if err.Error() != expectedErrMsg {
+			t.Fatalf("should error. got err = %v, want %v", err, expectedErrMsg)
 		}
 	})
 
@@ -173,7 +183,7 @@ func TestValidateMetadata(t *testing.T) {
 	}
 }
 
-func TestNewCLIPlugin_PathError(t *testing.T) {
+func TestNewCLIPlugin_Error(t *testing.T) {
 	ctx := context.Background()
 	t.Run("plugin directory exists without executable.", func(t *testing.T) {
 		p, err := NewCLIPlugin(ctx, "emptyplugin", "./testdata/plugins/emptyplugin/notation-emptyplugin")
@@ -186,14 +196,34 @@ func TestNewCLIPlugin_PathError(t *testing.T) {
 	})
 
 	t.Run("plugin is not a regular file", func(t *testing.T) {
+		expectedErrMsg := "plugin executable file is not a regular file"
 		p, err := NewCLIPlugin(ctx, "badplugin", "./testdata/plugins/badplugin/notation-badplugin")
-		if !errors.Is(err, ErrNotRegularFile) {
-			t.Errorf("NewCLIPlugin() error = %v, want %v", err, ErrNotRegularFile)
+		if err.Error() != expectedErrMsg {
+			t.Errorf("NewCLIPlugin() error = %v, want %v", err, expectedErrMsg)
 		}
 		if p != nil {
 			t.Errorf("NewCLIPlugin() plugin = %v, want nil", p)
 		}
 	})
+
+	t.Run("plugin timeout error", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+		expectedErrMsg := "'sleep 2' command execution timeout: signal: killed"
+		ctxWithTimout, cancel := context.WithTimeout(ctx, 10 * time.Millisecond)
+		defer cancel()
+
+		var twoSeconds proto.Command
+		twoSeconds = "2"
+		_, _, err := execCommander{}.Output(ctxWithTimout, "sleep", twoSeconds, nil);
+		if err == nil {
+			t.Errorf("execCommander{}.Output() expected error = %v, got nil", expectedErrMsg)
+		}
+		if err.Error() != expectedErrMsg {
+			t.Errorf("execCommander{}.Output() error = %v, want %v", err, expectedErrMsg)
+		}
+	})
 }
 
 func TestNewCLIPlugin_ValidError(t *testing.T) {
@@ -205,23 +235,23 @@ func TestNewCLIPlugin_ValidError(t *testing.T) {
 	t.Run("command no response", func(t *testing.T) {
 		executor = testCommander{}
 		_, err := p.GetMetadata(ctx, &proto.GetMetadataRequest{})
-		if !strings.Contains(err.Error(), ErrNotCompliant.Error()) {
-			t.Fatal("should fail the operation.")
+		if _, ok := err.(*PluginMalformedError); !ok {
+			t.Fatal("should return plugin validity error")
 		}
 	})
 
 	t.Run("invalid json", func(t *testing.T) {
 		executor = testCommander{stdout: []byte("content")}
 		_, err := p.GetMetadata(ctx, &proto.GetMetadataRequest{})
-		if !strings.Contains(err.Error(), ErrNotCompliant.Error()) {
-			t.Fatal("should fail the operation.")
+		if _, ok := err.(*PluginMalformedError); !ok {
+			t.Fatal("should return plugin validity error")
 		}
 	})
 
 	t.Run("invalid metadata name", func(t *testing.T) {
 		executor = testCommander{stdout: metadataJSON(invalidMetadataName)}
 		_, err := p.GetMetadata(ctx, &proto.GetMetadataRequest{})
-		if !strings.Contains(err.Error(), "executable name must be") {
+		if !strings.Contains(err.Error(), "executable file name must be") {
 			t.Fatal("should fail the operation.")
 		}
 	})
@@ -229,8 +259,8 @@ func TestNewCLIPlugin_ValidError(t *testing.T) {
 	t.Run("invalid metadata content", func(t *testing.T) {
 		executor = testCommander{stdout: metadataJSON(proto.GetMetadataResponse{Name: "foo"})}
 		_, err := p.GetMetadata(ctx, &proto.GetMetadataRequest{})
-		if !strings.Contains(err.Error(), "invalid metadata") {
-			t.Fatal("should fail the operation.")
+		if _, ok := err.(*PluginMalformedError); !ok {
+			t.Fatal("should be plugin validity error.")
 		}
 	})
 

plugin/proto/algorithm.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
 import (
@@ -5,67 +18,74 @@ import (
 	"fmt"
 
 	"github.com/notaryproject/notation-core-go/signature"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 )
 
 // KeySpec is type of the signing algorithm, including algorithm and size.
-type KeySpec string
+//
+// Deprecated: KeySpec exists for historical compatibility and should not be used.
+// To access KeySpec, use the notation-plugin-framework-go's [plugin.KeySpec] type.
+type KeySpec = plugin.KeySpec
 
 // one of the following supported key spec names.
 //
-// https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
+// Deprecated: KeySpec exists for historical compatibility and should not be used.
+// To access KeySpec, use the notation-plugin-framework-go's [plugin.KeySpec].
+//
+// [keys spec]: https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
 const (
-	KeySpecRSA2048 KeySpec = "RSA-2048"
-	KeySpecRSA3072 KeySpec = "RSA-3072"
-	KeySpecRSA4096 KeySpec = "RSA-4096"
-	KeySpecEC256   KeySpec = "EC-256"
-	KeySpecEC384   KeySpec = "EC-384"
-	KeySpecEC521   KeySpec = "EC-521"
+	KeySpecRSA2048 = plugin.KeySpecRSA2048
+	KeySpecRSA3072 = plugin.KeySpecRSA3072
+	KeySpecRSA4096 = plugin.KeySpecRSA4096
+	KeySpecEC256   = plugin.KeySpecEC256
+	KeySpecEC384   = plugin.KeySpecEC384
+	KeySpecEC521   = plugin.KeySpecEC521
 )
 
 // EncodeKeySpec returns the name of a keySpec according to the spec.
-func EncodeKeySpec(k signature.KeySpec) (KeySpec, error) {
+func EncodeKeySpec(k signature.KeySpec) (plugin.KeySpec, error) {
 	switch k.Type {
 	case signature.KeyTypeEC:
 		switch k.Size {
 		case 256:
-			return KeySpecEC256, nil
+			return plugin.KeySpecEC256, nil
 		case 384:
-			return KeySpecEC384, nil
+			return plugin.KeySpecEC384, nil
 		case 521:
-			return KeySpecEC521, nil
+			return plugin.KeySpecEC521, nil
 		}
 	case signature.KeyTypeRSA:
 		switch k.Size {
 		case 2048:
-			return KeySpecRSA2048, nil
+			return plugin.KeySpecRSA2048, nil
 		case 3072:
-			return KeySpecRSA3072, nil
+			return plugin.KeySpecRSA3072, nil
 		case 4096:
-			return KeySpecRSA4096, nil
+			return plugin.KeySpecRSA4096, nil
 		}
 	}
 	return "", fmt.Errorf("invalid KeySpec %q", k)
 }
 
 // DecodeKeySpec parses keySpec name to a signature.keySpec type.
-func DecodeKeySpec(k KeySpec) (keySpec signature.KeySpec, err error) {
+func DecodeKeySpec(k plugin.KeySpec) (keySpec signature.KeySpec, err error) {
 	switch k {
-	case KeySpecRSA2048:
+	case plugin.KeySpecRSA2048:
 		keySpec.Size = 2048
 		keySpec.Type = signature.KeyTypeRSA
-	case KeySpecRSA3072:
+	case plugin.KeySpecRSA3072:
 		keySpec.Size = 3072
 		keySpec.Type = signature.KeyTypeRSA
-	case KeySpecRSA4096:
+	case plugin.KeySpecRSA4096:
 		keySpec.Size = 4096
 		keySpec.Type = signature.KeyTypeRSA
-	case KeySpecEC256:
+	case plugin.KeySpecEC256:
 		keySpec.Size = 256
 		keySpec.Type = signature.KeyTypeEC
-	case KeySpecEC384:
+	case plugin.KeySpecEC384:
 		keySpec.Size = 384
 		keySpec.Type = signature.KeyTypeEC
-	case KeySpecEC521:
+	case plugin.KeySpecEC521:
 		keySpec.Size = 521
 		keySpec.Type = signature.KeyTypeEC
 	default:
@@ -75,92 +95,104 @@ func DecodeKeySpec(k KeySpec) (keySpec signature.KeySpec, err error) {
 	return
 }
 
-// HashAlgorithm is the type of a hash algorithm.
-type HashAlgorithm string
+// HashAlgorithm is the type of hash algorithm.
+//
+// Deprecated: HashAlgorithm exists for historical compatibility and should not be used.
+// To access HashAlgorithm, use the notation-plugin-framework-go's [plugin.HashAlgorithm] type.
+type HashAlgorithm = plugin.HashAlgorithm
 
 // one of the following supported hash algorithm names.
 //
-// https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
+// Deprecated: HashAlgorithm exists for historical compatibility and should not be used.
+// To access HashAlgorithm, use the notation-plugin-framework-go's [plugin.HashAlgorithm] type.
+//
+// [hash algorithm]: https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
 const (
-	HashAlgorithmSHA256 HashAlgorithm = "SHA-256"
-	HashAlgorithmSHA384 HashAlgorithm = "SHA-384"
-	HashAlgorithmSHA512 HashAlgorithm = "SHA-512"
+	HashAlgorithmSHA256 = plugin.HashAlgorithmSHA256
+	HashAlgorithmSHA384 = plugin.HashAlgorithmSHA384
+	HashAlgorithmSHA512 = plugin.HashAlgorithmSHA512
 )
 
 // HashAlgorithmFromKeySpec returns the name of hash function according to the spec.
-func HashAlgorithmFromKeySpec(k signature.KeySpec) (HashAlgorithm, error) {
+func HashAlgorithmFromKeySpec(k signature.KeySpec) (plugin.HashAlgorithm, error) {
 	switch k.Type {
 	case signature.KeyTypeEC:
 		switch k.Size {
 		case 256:
-			return HashAlgorithmSHA256, nil
+			return plugin.HashAlgorithmSHA256, nil
 		case 384:
-			return HashAlgorithmSHA384, nil
+			return plugin.HashAlgorithmSHA384, nil
 		case 521:
-			return HashAlgorithmSHA512, nil
+			return plugin.HashAlgorithmSHA512, nil
 		}
 	case signature.KeyTypeRSA:
 		switch k.Size {
 		case 2048:
-			return HashAlgorithmSHA256, nil
+			return plugin.HashAlgorithmSHA256, nil
 		case 3072:
-			return HashAlgorithmSHA384, nil
+			return plugin.HashAlgorithmSHA384, nil
 		case 4096:
-			return HashAlgorithmSHA512, nil
+			return plugin.HashAlgorithmSHA512, nil
 		}
 	}
 	return "", fmt.Errorf("invalid KeySpec %q", k)
 }
 
 // SignatureAlgorithm is the type of signature algorithm
-type SignatureAlgorithm string
-
-// one of the following supported signing algorithm names.
 //
-// https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
+// Deprecated: SignatureAlgorithm exists for historical compatibility and should not be used.
+// To access SignatureAlgorithm, use the notation-plugin-framework-go's [plugin.SignatureAlgorithm] type.
+type SignatureAlgorithm = plugin.SignatureAlgorithm
+
+// one of the following supported [signing algorithm] names.
+//
+// Deprecated: SignatureAlgorithm exists for historical compatibility and should not be used.
+// To access SignatureAlgorithm, use the notation-plugin-framework-go's [plugin.SignatureAlgorithm] type.
+//
+// [signing algorithm]: https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
 const (
-	SignatureAlgorithmECDSA_SHA256      SignatureAlgorithm = "ECDSA-SHA-256"
-	SignatureAlgorithmECDSA_SHA384      SignatureAlgorithm = "ECDSA-SHA-384"
-	SignatureAlgorithmECDSA_SHA512      SignatureAlgorithm = "ECDSA-SHA-512"
-	SignatureAlgorithmRSASSA_PSS_SHA256 SignatureAlgorithm = "RSASSA-PSS-SHA-256"
-	SignatureAlgorithmRSASSA_PSS_SHA384 SignatureAlgorithm = "RSASSA-PSS-SHA-384"
-	SignatureAlgorithmRSASSA_PSS_SHA512 SignatureAlgorithm = "RSASSA-PSS-SHA-512"
+	SignatureAlgorithmECDSA_SHA256      = plugin.SignatureAlgorithmECDSA_SHA256
+	SignatureAlgorithmECDSA_SHA384      = plugin.SignatureAlgorithmECDSA_SHA384
+	SignatureAlgorithmECDSA_SHA512      = plugin.SignatureAlgorithmECDSA_SHA512
+	SignatureAlgorithmRSASSA_PSS_SHA256 = plugin.SignatureAlgorithmRSASSA_PSS_SHA256
+	SignatureAlgorithmRSASSA_PSS_SHA384 = plugin.SignatureAlgorithmRSASSA_PSS_SHA384
+	SignatureAlgorithmRSASSA_PSS_SHA512 = plugin.SignatureAlgorithmRSASSA_PSS_SHA512
 )
 
 // EncodeSigningAlgorithm returns the signing algorithm name of an algorithm
 // according to the spec.
-func EncodeSigningAlgorithm(alg signature.Algorithm) (SignatureAlgorithm, error) {
+func EncodeSigningAlgorithm(alg signature.Algorithm) (plugin.SignatureAlgorithm, error) {
 	switch alg {
 	case signature.AlgorithmES256:
-		return SignatureAlgorithmECDSA_SHA256, nil
+		return plugin.SignatureAlgorithmECDSA_SHA256, nil
 	case signature.AlgorithmES384:
-		return SignatureAlgorithmECDSA_SHA384, nil
+		return plugin.SignatureAlgorithmECDSA_SHA384, nil
 	case signature.AlgorithmES512:
-		return SignatureAlgorithmECDSA_SHA512, nil
+		return plugin.SignatureAlgorithmECDSA_SHA512, nil
 	case signature.AlgorithmPS256:
-		return SignatureAlgorithmRSASSA_PSS_SHA256, nil
+		return plugin.SignatureAlgorithmRSASSA_PSS_SHA256, nil
 	case signature.AlgorithmPS384:
-		return SignatureAlgorithmRSASSA_PSS_SHA384, nil
+		return plugin.SignatureAlgorithmRSASSA_PSS_SHA384, nil
 	case signature.AlgorithmPS512:
-		return SignatureAlgorithmRSASSA_PSS_SHA512, nil
+		return plugin.SignatureAlgorithmRSASSA_PSS_SHA512, nil
 	}
 	return "", fmt.Errorf("invalid algorithm %q", alg)
 }
 
 // DecodeSigningAlgorithm parses the signing algorithm name from a given string.
-func DecodeSigningAlgorithm(raw SignatureAlgorithm) (signature.Algorithm, error) {
+func DecodeSigningAlgorithm(raw plugin.SignatureAlgorithm) (signature.Algorithm, error) {
 	switch raw {
-	case SignatureAlgorithmECDSA_SHA256:
+	case plugin.SignatureAlgorithmECDSA_SHA256:
 		return signature.AlgorithmES256, nil
-	case SignatureAlgorithmECDSA_SHA384:
+	case plugin.SignatureAlgorithmECDSA_SHA384:
 		return signature.AlgorithmES384, nil
-	case SignatureAlgorithmECDSA_SHA512:
+	case plugin.SignatureAlgorithmECDSA_SHA512:
 		return signature.AlgorithmES512, nil
-	case SignatureAlgorithmRSASSA_PSS_SHA256:
+	case plugin.SignatureAlgorithmRSASSA_PSS_SHA256:
 		return signature.AlgorithmPS256, nil
-	case SignatureAlgorithmRSASSA_PSS_SHA384:
+	case plugin.SignatureAlgorithmRSASSA_PSS_SHA384:
 		return signature.AlgorithmPS384, nil
-	case SignatureAlgorithmRSASSA_PSS_SHA512:
+	case plugin.SignatureAlgorithmRSASSA_PSS_SHA512:
 		return signature.AlgorithmPS512, nil
 	}
 	return 0, errors.New("unknown signing algorithm")

plugin/proto/algorithm_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
 import (
@@ -215,7 +228,7 @@ func TestDecodeKeySpec(t *testing.T) {
 		},
 		{
 			name:      "Unsupported key spec",
-			raw:       "unsuppored",
+			raw:       "unsupported",
 			expected:  signature.KeySpec{},
 			expectErr: true,
 		},

plugin/proto/errors.go

@@ -1,51 +1,78 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
 import (
 	"encoding/json"
 	"errors"
 	"fmt"
+
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
 )
 
-type ErrorCode string
+// Deprecated: ErrorCode exists for historical compatibility and should not be used.
+// To access ErrorCode, use the notation-plugin-framework-go's plugin.ErrorCode type.
+type ErrorCode = plugin.ErrorCode
 
 const (
-	// Any of the required request fields was empty,
-	// or a value was malformed/invalid.
-	ErrorCodeValidation ErrorCode = "VALIDATION_ERROR"
+	// ErrorCodeValidation is used when any of the required request fields is empty ormalformed/invalid.
+	//
+	// Deprecated: ErrorCodeValidation exists for historical compatibility and should not be used.
+	// To access ErrorCodeValidation, use the notation-plugin-framework-go's [plugin.ErrorCodeValidation].
+	ErrorCodeValidation = plugin.ErrorCodeValidation
 
-	// The contract version used in the request is unsupported.
-	ErrorCodeUnsupportedContractVersion ErrorCode = "UNSUPPORTED_CONTRACT_VERSION"
+	// ErrorCodeUnsupportedContractVersion is used when when the contract version used in the request is unsupported.
+	//
+	// Deprecated: ErrorCodeUnsupportedContractVersion exists for historical compatibility and should not be used.
+	// To access ErrorCodeUnsupportedContractVersion, use the notation-plugin-framework-go's [plugin.ErrorCodeUnsupportedContractVersion].
+	ErrorCodeUnsupportedContractVersion = plugin.ErrorCodeUnsupportedContractVersion
 
-	// Authentication/authorization error to use given key.
-	ErrorCodeAccessDenied ErrorCode = "ACCESS_DENIED"
+	// ErrorCodeAccessDenied is used when user doesn't have required permission to access the key.
+	//
+	// Deprecated: ErrorCodeAccessDenied exists for historical compatibility and should not be used.
+	// To access ErrorCodeAccessDenied, use the notation-plugin-framework-go's [plugin.ErrorCodeAccessDenied].
+	ErrorCodeAccessDenied = plugin.ErrorCodeAccessDenied
 
-	// The operation to generate signature timed out
+	// ErrorCodeTimeout is used when an operation to generate signature timed out and can be retried by Notation.
+	//
+	// Deprecated: ErrorCodeTimeout exists for historical compatibility and should not be used.
+	// To access ErrorCodeTimeout, use the notation-plugin-framework-go's [plugin.ErrorCodeTimeout].
+	ErrorCodeTimeout = plugin.ErrorCodeTimeout
+
+	// ErrorCodeThrottled is used when an operation to generate signature was throttles
 	// and can be retried by Notation.
-	ErrorCodeTimeout ErrorCode = "TIMEOUT"
+	//
+	// Deprecated: ErrorCodeThrottled exists for historical compatibility and should not be used.
+	// To access ErrorCodeThrottled, use the notation-plugin-framework-go's [plugin.ErrorCodeThrottled].
+	ErrorCodeThrottled = plugin.ErrorCodeThrottled
 
-	// The operation to generate signature was throttles
-	// and can be retried by Notation.
-	ErrorCodeThrottled ErrorCode = "THROTTLED"
-
-	// Any general error that does not fall into any categories.
-	ErrorCodeGeneric ErrorCode = "ERROR"
+	// ErrorCodeGeneric  is used when an general error occurred that does not fall into any categories.
+	//
+	// Deprecated: ErrorCodeGeneric exists for historical compatibility and should not be used.
+	// To access ErrorCodeGeneric, use the notation-plugin-framework-go's [plugin.ErrorCodeGeneric].
+	ErrorCodeGeneric = plugin.ErrorCodeGeneric
 )
 
-type jsonErr struct {
-	Code     ErrorCode         `json:"errorCode"`
-	Message  string            `json:"errorMessage,omitempty"`
-	Metadata map[string]string `json:"errorMetadata,omitempty"`
-}
-
 // RequestError is the common error response for any request.
 type RequestError struct {
-	Code     ErrorCode
+	Code     plugin.ErrorCode
 	Err      error
 	Metadata map[string]string
 }
 
 func (e RequestError) Error() string {
-	return fmt.Sprintf("%s: %v", e.Code, e.Err)
+	return fmt.Sprintf("%v", e.Err)
 }
 
 func (e RequestError) Unwrap() error {
@@ -70,19 +97,19 @@ func (e RequestError) MarshalJSON() ([]byte, error) {
 	if e.Err != nil {
 		msg = e.Err.Error()
 	}
-	return json.Marshal(jsonErr{e.Code, msg, e.Metadata})
+	return json.Marshal(plugin.Error{ErrCode: e.Code, Message: msg, Metadata: e.Metadata})
 }
 
 func (e *RequestError) UnmarshalJSON(data []byte) error {
-	var tmp jsonErr
+	var tmp plugin.Error
 	err := json.Unmarshal(data, &tmp)
 	if err != nil {
 		return err
 	}
-	if tmp.Code == "" && tmp.Message == "" && tmp.Metadata == nil {
+	if tmp.ErrCode == "" && tmp.Message == "" && tmp.Metadata == nil {
 		return errors.New("incomplete json")
 	}
-	*e = RequestError{Code: tmp.Code, Metadata: tmp.Metadata}
+	*e = RequestError{Code: tmp.ErrCode, Metadata: tmp.Metadata}
 	if tmp.Message != "" {
 		e.Err = errors.New(tmp.Message)
 	}

plugin/proto/errors_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
 import (
@@ -9,7 +22,7 @@ import (
 
 func TestRequestError_Error(t *testing.T) {
 	err := RequestError{Code: ErrorCodeAccessDenied, Err: errors.New("an error")}
-	want := string(ErrorCodeAccessDenied) + ": an error"
+	want := "an error"
 	if got := err.Error(); got != want {
 		t.Errorf("RequestError.Error() = %v, want %v", got, want)
 	}

plugin/proto/metadata.go

@@ -1,36 +1,28 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
-// GetMetadataRequest contains the parameters passed in a get-plugin-metadata
-// request.
-type GetMetadataRequest struct {
-	PluginConfig map[string]string `json:"pluginConfig,omitempty"`
-}
+import "github.com/notaryproject/notation-plugin-framework-go/plugin"
 
-func (GetMetadataRequest) Command() Command {
-	return CommandGetMetadata
-}
+// GetMetadataRequest contains the parameters passed in a get-plugin-metadata request.
+//
+// Deprecated: GetMetadataRequest exists for historical compatibility and should not be used.
+// To access GetMetadataRequest, use the notation-plugin-framework-go's [plugin.GetMetadataRequest] type.
+type GetMetadataRequest = plugin.GetMetadataRequest
 
 // GetMetadataResponse provided by the plugin.
-type GetMetadataResponse struct {
-	Name                      string       `json:"name"`
-	Description               string       `json:"description"`
-	Version                   string       `json:"version"`
-	URL                       string       `json:"url"`
-	SupportedContractVersions []string     `json:"supportedContractVersions"`
-	Capabilities              []Capability `json:"capabilities"`
-}
-
-// HasCapability return true if the metadata states that the
-// capability is supported.
-// Returns true if capability is empty.
-func (resp *GetMetadataResponse) HasCapability(capability Capability) bool {
-	if capability == "" {
-		return true
-	}
-	for _, c := range resp.Capabilities {
-		if c == capability {
-			return true
-		}
-	}
-	return false
-}
+//
+// Deprecated: GetMetadataResponse exists for historical compatibility and should not be used.
+// To access GetMetadataResponse, use the notation-plugin-framework-go's [plugin.GetMetadataResponse] type.
+type GetMetadataResponse = plugin.GetMetadataResponse

plugin/proto/metadata_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
 import (

plugin/proto/proto.go

@@ -1,65 +1,120 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package proto defines the protocol layer for communication between notation
 // and notation external plugin.
 package proto
 
+import "github.com/notaryproject/notation-plugin-framework-go/plugin"
+
 // Prefix is the prefix required on all plugin binary names.
-const Prefix = "notation-"
+//
+// Deprecated: Prefix exists for historical compatibility and should not be used.
+// To access Prefix, use the notation-plugin-framework-go's [plugin.BinaryPrefix] type.
+const Prefix = plugin.BinaryPrefix
 
 // ContractVersion is the <major>.<minor> version of the plugin contract.
-const ContractVersion = "1.0"
+//
+// Deprecated: ContractVersion exists for historical compatibility and should not be used.
+// To access ContractVersion, use the notation-plugin-framework-go's [plugin.ContractVersion] type.
+const ContractVersion = plugin.ContractVersion
 
 // Command is a CLI command available in the plugin contract.
-type Command string
+//
+// Deprecated: Command exists for historical compatibility and should not be used.
+// To access Command, use the notation-plugin-framework-go's [plugin.Command] type.
+type Command = plugin.Command
 
 // Request defines a plugin request, which is always associated to a command.
-type Request interface {
-	Command() Command
-}
+//
+// Deprecated: Request exists for historical compatibility and should not be used.
+// To access Request, use the notation-plugin-framework-go's [plugin.Request] type.
+type Request = plugin.Request
 
 const (
 	// CommandGetMetadata is the name of the plugin command
 	// which must be supported by every plugin and returns the
 	// plugin metadata.
-	CommandGetMetadata Command = "get-plugin-metadata"
+	//
+	// Deprecated: CommandGetMetadata exists for historical compatibility and should not be used.
+	// To access CommandGetMetadata, use the notation-plugin-framework-go's [plugin.CommandGetMetadata].
+	CommandGetMetadata = plugin.CommandGetMetadata
 
 	// CommandDescribeKey is the name of the plugin command
 	// which must be supported by every plugin that has the
 	// SIGNATURE_GENERATOR.RAW capability.
-	CommandDescribeKey Command = "describe-key"
+	//
+	// Deprecated: CommandDescribeKey exists for historical compatibility and should not be used.
+	// To access CommandDescribeKey, use the notation-plugin-framework-go's [plugin.CommandDescribeKey].
+	CommandDescribeKey = plugin.CommandDescribeKey
 
 	// CommandGenerateSignature is the name of the plugin command
 	// which must be supported by every plugin that has the
 	// SIGNATURE_GENERATOR.RAW capability.
-	CommandGenerateSignature Command = "generate-signature"
+	//
+	// Deprecated: CommandGenerateSignature exists for historical compatibility and should not be used.
+	// To access CommandGenerateSignature, use the notation-plugin-framework-go's [plugin.CommandGenerateSignature].
+	CommandGenerateSignature = plugin.CommandGenerateSignature
 
 	// CommandGenerateEnvelope is the name of the plugin command
 	// which must be supported by every plugin that has the
 	// SIGNATURE_GENERATOR.ENVELOPE capability.
-	CommandGenerateEnvelope Command = "generate-envelope"
+	//
+	// Deprecated: CommandGenerateEnvelope exists for historical compatibility and should not be used.
+	// To access CommandGenerateEnvelope, use the notation-plugin-framework-go's [plugin.CommandGenerateEnvelope].
+	CommandGenerateEnvelope = plugin.CommandGenerateEnvelope
 
 	// CommandVerifySignature is the name of the plugin command
 	// which must be supported by every plugin that has
 	// any SIGNATURE_VERIFIER.* capability
-	CommandVerifySignature Command = "verify-signature"
+	//
+	// Deprecated: CommandVerifySignature exists for historical compatibility and should not be used.
+	// To access CommandVerifySignature, use the notation-plugin-framework-go's [plugin.CommandVerifySignature].
+	CommandVerifySignature = plugin.CommandVerifySignature
 )
 
 // Capability is a feature available in the plugin contract.
-type Capability string
+//
+// Deprecated: Capability exists for historical compatibility and should not be used.
+// To access Capability, use the notation-plugin-framework-go's [plugin.Capability] type.
+type Capability = plugin.Capability
 
 const (
 	// CapabilitySignatureGenerator is the name of the capability
 	// for a plugin to support generating raw signatures.
-	CapabilitySignatureGenerator Capability = "SIGNATURE_GENERATOR.RAW"
+	//
+	// Deprecated: CapabilitySignatureGenerator exists for historical compatibility and should not be used.
+	// To access CapabilitySignatureGenerator, use the notation-plugin-framework-go's [plugin.CapabilitySignatureGenerator].
+	CapabilitySignatureGenerator = plugin.CapabilitySignatureGenerator
 
 	// CapabilityEnvelopeGenerator is the name of the capability
 	// for a plugin to support generating envelope signatures.
-	CapabilityEnvelopeGenerator Capability = "SIGNATURE_GENERATOR.ENVELOPE"
+	//
+	// Deprecated: CapabilityEnvelopeGenerator exists for historical compatibility and should not be used.
+	// To access CapabilityEnvelopeGenerator, use the notation-plugin-framework-go's [plugin.CapabilityEnvelopeGenerator].
+	CapabilityEnvelopeGenerator = plugin.CapabilityEnvelopeGenerator
 
 	// CapabilityTrustedIdentityVerifier is the name of the
 	// capability for a plugin to support verifying trusted identities.
-	CapabilityTrustedIdentityVerifier Capability = "SIGNATURE_VERIFIER.TRUSTED_IDENTITY"
+	//
+	// Deprecated: CapabilityTrustedIdentityVerifier exists for historical compatibility and should not be used.
+	// To access CapabilityTrustedIdentityVerifier, use the notation-plugin-framework-go's [plugin.CapabilityTrustedIdentityVerifier].
+	CapabilityTrustedIdentityVerifier = plugin.CapabilityTrustedIdentityVerifier
 
 	// CapabilityRevocationCheckVerifier is the name of the
 	// capability for a plugin to support verifying revocation checks.
-	CapabilityRevocationCheckVerifier Capability = "SIGNATURE_VERIFIER.REVOCATION_CHECK"
+	//
+	// Deprecated: CapabilityRevocationCheckVerifier exists for historical compatibility and should not be used.
+	// To access CapabilityRevocationCheckVerifier, use the notation-plugin-framework-go's [plugin.CapabilityRevocationCheckVerifier].
+	CapabilityRevocationCheckVerifier = plugin.CapabilityRevocationCheckVerifier
 )

plugin/proto/sign.go

@@ -1,71 +1,54 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
-// DescribeKeyRequest contains the parameters passed in a describe-key request.
-type DescribeKeyRequest struct {
-	ContractVersion string            `json:"contractVersion"`
-	KeyID           string            `json:"keyId"`
-	PluginConfig    map[string]string `json:"pluginConfig,omitempty"`
-}
+import "github.com/notaryproject/notation-plugin-framework-go/plugin"
 
-func (DescribeKeyRequest) Command() Command {
-	return CommandDescribeKey
-}
+// DescribeKeyRequest contains the parameters passed in a describe-key request.
+//
+// Deprecated: DescribeKeyRequest exists for historical compatibility and should not be used.
+// To access DescribeKeyRequest, use the notation-plugin-framework-go's [plugin.DescribeKeyRequest] type.
+type DescribeKeyRequest = plugin.DescribeKeyRequest
 
 // DescribeKeyResponse is the response of a describe-key request.
-type DescribeKeyResponse struct {
-	// The same key id as passed in the request.
-	KeyID string `json:"keyId"`
-
-	// One of following supported key types:
-	// https://github.com/notaryproject/notaryproject/blob/main/specs/signature-specification.md#algorithm-selection
-	KeySpec KeySpec `json:"keySpec"`
-}
+//
+// Deprecated: DescribeKeyResponse exists for historical compatibility and should not be used.
+// To access DescribeKeyResponse, use the notation-plugin-framework-go's [plugin.DescribeKeyResponse] type.
+type DescribeKeyResponse = plugin.DescribeKeyResponse
 
 // GenerateSignatureRequest contains the parameters passed in a
 // generate-signature request.
-type GenerateSignatureRequest struct {
-	ContractVersion string            `json:"contractVersion"`
-	KeyID           string            `json:"keyId"`
-	KeySpec         KeySpec           `json:"keySpec"`
-	Hash            HashAlgorithm     `json:"hashAlgorithm"`
-	Payload         []byte            `json:"payload"`
-	PluginConfig    map[string]string `json:"pluginConfig,omitempty"`
-}
-
-func (GenerateSignatureRequest) Command() Command {
-	return CommandGenerateSignature
-}
+//
+// Deprecated: GenerateSignatureRequest exists for historical compatibility and should not be used.
+// To access GenerateSignatureRequest, use the notation-plugin-framework-go's [plugin.GenerateSignatureRequest] type.
+type GenerateSignatureRequest = plugin.GenerateSignatureRequest
 
 // GenerateSignatureResponse is the response of a generate-signature request.
-type GenerateSignatureResponse struct {
-	KeyID            string `json:"keyId"`
-	Signature        []byte `json:"signature"`
-	SigningAlgorithm string `json:"signingAlgorithm"`
-
-	// Ordered list of certificates starting with leaf certificate
-	// and ending with root certificate.
-	CertificateChain [][]byte `json:"certificateChain"`
-}
+//
+// Deprecated: GenerateSignatureResponse exists for historical compatibility and should not be used.
+// To access GenerateSignatureResponse, use the notation-plugin-framework-go's [plugin.GenerateSignatureResponse] type.
+type GenerateSignatureResponse = plugin.GenerateSignatureResponse
 
 // GenerateEnvelopeRequest contains the parameters passed in a generate-envelope
 // request.
-type GenerateEnvelopeRequest struct {
-	ContractVersion         string            `json:"contractVersion"`
-	KeyID                   string            `json:"keyId"`
-	PayloadType             string            `json:"payloadType"`
-	SignatureEnvelopeType   string            `json:"signatureEnvelopeType"`
-	Payload                 []byte            `json:"payload"`
-	ExpiryDurationInSeconds uint64            `json:"expiryDurationInSeconds,omitempty"`
-	PluginConfig            map[string]string `json:"pluginConfig,omitempty"`
-}
-
-func (GenerateEnvelopeRequest) Command() Command {
-	return CommandGenerateEnvelope
-}
+//
+// Deprecated: GenerateEnvelopeRequest exists for historical compatibility and should not be used.
+// To access GenerateEnvelopeRequest, use the notation-plugin-framework-go's [plugin.GenerateEnvelopeRequest] type.
+type GenerateEnvelopeRequest = plugin.GenerateEnvelopeRequest
 
 // GenerateEnvelopeResponse is the response of a generate-envelope request.
-type GenerateEnvelopeResponse struct {
-	SignatureEnvelope     []byte            `json:"signatureEnvelope"`
-	SignatureEnvelopeType string            `json:"signatureEnvelopeType"`
-	Annotations           map[string]string `json:"annotations,omitempty"`
-}
+//
+// Deprecated: GenerateEnvelopeResponse exists for historical compatibility and should not be used.
+// To access GenerateEnvelopeResponse, use the notation-plugin-framework-go's [plugin.GenerateEnvelopeResponse] type.
+type GenerateEnvelopeResponse = plugin.GenerateEnvelopeResponse

plugin/proto/verify.go

@@ -1,51 +1,56 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package proto
 
-import "time"
+import (
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
+)
 
 // VerifySignatureRequest contains the parameters passed in a verify-signature
 // request.
-type VerifySignatureRequest struct {
-	ContractVersion string            `json:"contractVersion"`
-	Signature       Signature         `json:"signature"`
-	TrustPolicy     TrustPolicy       `json:"trustPolicy"`
-	PluginConfig    map[string]string `json:"pluginConfig,omitempty"`
-}
-
-func (VerifySignatureRequest) Command() Command {
-	return CommandVerifySignature
-}
+//
+// Deprecated: VerifySignatureRequest exists for historical compatibility and should not be used.
+// To access VerifySignatureRequest, use the notation-plugin-framework-go'[s plugin.VerifySignatureRequest] type.
+type VerifySignatureRequest = plugin.VerifySignatureRequest
 
 // Signature represents a signature pulled from the envelope
-type Signature struct {
-	CriticalAttributes    CriticalAttributes `json:"criticalAttributes"`
-	UnprocessedAttributes []string           `json:"unprocessedAttributes"`
-	CertificateChain      [][]byte           `json:"certificateChain"`
-}
+//
+// Deprecated: Signature exists for historical compatibility and should not be used.
+// To access Signature, use the notation-plugin-framework-go's [plugin.Signature] type.
+type Signature = plugin.Signature
 
-// CriticalAttributes contains all Notary V2 defined critical
+// CriticalAttributes contains all Notary Project defined critical
 // attributes and their values in the signature envelope
-type CriticalAttributes struct {
-	ContentType          string                 `json:"contentType"`
-	SigningScheme        string                 `json:"signingScheme"`
-	Expiry               *time.Time             `json:"expiry,omitempty"`
-	AuthenticSigningTime *time.Time             `json:"authenticSigningTime,omitempty"`
-	ExtendedAttributes   map[string]interface{} `json:"extendedAttributes,omitempty"`
-}
+//
+// Deprecated: CriticalAttributes exists for historical compatibility and should not be used.
+// To access CriticalAttributes, use the notation-plugin-framework-go's [plugin.CriticalAttributes] type.
+type CriticalAttributes = plugin.CriticalAttributes
 
 // TrustPolicy represents trusted identities that sign the artifacts
-type TrustPolicy struct {
-	TrustedIdentities     []string     `json:"trustedIdentities"`
-	SignatureVerification []Capability `json:"signatureVerification"`
-}
+//
+// Deprecated: TrustPolicy exists for historical compatibility and should not be used.
+// To access TrustPolicy, use the notation-plugin-framework-go's [plugin.TrustPolicy] type.
+type TrustPolicy = plugin.TrustPolicy
 
 // VerifySignatureResponse is the response of a verify-signature request.
-type VerifySignatureResponse struct {
-	VerificationResults map[Capability]*VerificationResult `json:"verificationResults"`
-	ProcessedAttributes []interface{}                      `json:"processedAttributes"`
-}
+//
+// Deprecated: VerifySignatureResponse exists for historical compatibility and should not be used.
+// To access VerifySignatureResponse, use the notation-plugin-framework-go's [plugin.VerifySignatureResponse] type.
+type VerifySignatureResponse = plugin.VerifySignatureResponse
 
-// VerificationResult is the result of a verification performed by the plugin
-type VerificationResult struct {
-	Success bool   `json:"success"`
-	Reason  string `json:"reason,omitempty"`
-}
+// VerificationResult is the result of a verification performed by the plugin.
+//
+// Deprecated: VerificationResult exists for historical compatibility and should not be used.
+// To access VerificationResult, use the notation-plugin-framework-go's [plugin.VerificationResult] type.
+type VerificationResult = plugin.VerificationResult

registry/interface.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package registry provides access to signatures in a registry
 package registry
 

registry/internal/artifactspec/artifact.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package artifactspec
 
 import ocispec "github.com/opencontainers/image-spec/specs-go/v1"

registry/mediatype.go

@@ -1,5 +1,18 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package registry
 
 // ArtifactTypeNotation specifies the artifact type for a notation object.
-// spec: https://github.com/notaryproject/notaryproject/blob/efc828223710f99ab9639d2d0f72d59036a8e80c/specs/signature-specification.md#storage
+// spec: https://github.com/notaryproject/specifications/blob/v1.1.0/specs/signature-specification.md#signature
 const ArtifactTypeNotation = "application/vnd.cncf.notary.signature"

registry/repository.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package registry
 
 import (
@@ -6,6 +19,7 @@ import (
 	"fmt"
 	"os"
 
+	"github.com/notaryproject/notation-go/log"
 	"github.com/notaryproject/notation-go/registry/internal/artifactspec"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"oras.land/oras-go/v2"
@@ -19,17 +33,17 @@ const (
 	maxManifestSizeLimit = 4 * 1024 * 1024  // 4 MiB
 )
 
-// RepositoryOptions provides user options when creating a Repository
+// RepositoryOptions provides user options when creating a [Repository]
 // it is kept for future extensibility
 type RepositoryOptions struct{}
 
-// repositoryClient implements Repository
+// repositoryClient implements [Repository]
 type repositoryClient struct {
 	oras.GraphTarget
 	RepositoryOptions
 }
 
-// NewRepository returns a new Repository.
+// NewRepository returns a new [Repository].
 // Known implementations of oras.GraphTarget:
 // - [remote.Repository](https://pkg.go.dev/oras.land/oras-go/v2/registry/remote#Repository)
 // - [oci.Store](https://pkg.go.dev/oras.land/oras-go/v2/content/oci#Store)
@@ -39,7 +53,7 @@ func NewRepository(target oras.GraphTarget) Repository {
 	}
 }
 
-// NewRepositoryWithOptions returns a new Repository with user specified
+// NewRepositoryWithOptions returns a new [Repository] with user specified
 // options.
 func NewRepositoryWithOptions(target oras.GraphTarget, opts RepositoryOptions) Repository {
 	return &repositoryClient{
@@ -48,7 +62,7 @@ func NewRepositoryWithOptions(target oras.GraphTarget, opts RepositoryOptions) R
 	}
 }
 
-// NewOCIRepository returns a new Repository with oci.Store as
+// NewOCIRepository returns a new [Repository] with oci.Store as
 // its oras.GraphTarget. `path` denotes directory path to the target OCI layout.
 func NewOCIRepository(path string, opts RepositoryOptions) (Repository, error) {
 	fileInfo, err := os.Stat(path)
@@ -79,7 +93,6 @@ func (c *repositoryClient) ListSignatures(ctx context.Context, desc ocispec.Desc
 	if repo, ok := c.GraphTarget.(registry.ReferrerLister); ok {
 		return repo.Referrers(ctx, desc, ArtifactTypeNotation, fn)
 	}
-
 	signatureManifests, err := signatureReferrers(ctx, c.GraphTarget, desc)
 	if err != nil {
 		return fmt.Errorf("failed to get referrers during ListSignatures due to %w", err)
@@ -97,7 +110,6 @@ func (c *repositoryClient) FetchSignatureBlob(ctx context.Context, desc ocispec.
 	if sigBlobDesc.Size > maxBlobSizeLimit {
 		return nil, ocispec.Descriptor{}, fmt.Errorf("signature blob too large: %d bytes", sigBlobDesc.Size)
 	}
-
 	var fetcher content.Fetcher = c.GraphTarget
 	if repo, ok := c.GraphTarget.(registry.Repository); ok {
 		fetcher = repo.Blobs()
@@ -150,6 +162,7 @@ func (c *repositoryClient) getSignatureBlobDesc(ctx context.Context, sigManifest
 
 	// get the signature blob descriptor from signature manifest
 	var signatureBlobs []ocispec.Descriptor
+
 	// OCI image manifest
 	if sigManifestDesc.MediaType == ocispec.MediaTypeImageManifest {
 		var sigManifest ocispec.Manifest
@@ -164,28 +177,27 @@ func (c *repositoryClient) getSignatureBlobDesc(ctx context.Context, sigManifest
 		}
 		signatureBlobs = sigManifest.Blobs
 	}
-
 	if len(signatureBlobs) != 1 {
 		return ocispec.Descriptor{}, fmt.Errorf("signature manifest requries exactly one signature envelope blob, got %d", len(signatureBlobs))
 	}
-
 	return signatureBlobs[0], nil
 }
 
 // uploadSignatureManifest uploads the signature manifest to the registry
 func (c *repositoryClient) uploadSignatureManifest(ctx context.Context, subject, blobDesc ocispec.Descriptor, annotations map[string]string) (ocispec.Descriptor, error) {
-	opts := oras.PackOptions{
+	opts := oras.PackManifestOptions{
 		Subject:             &subject,
 		ManifestAnnotations: annotations,
-		PackImageManifest:   true,
+		Layers:              []ocispec.Descriptor{blobDesc},
 	}
-
-	return oras.Pack(ctx, c.GraphTarget, ArtifactTypeNotation, []ocispec.Descriptor{blobDesc}, opts)
+	return oras.PackManifest(ctx, c.GraphTarget, oras.PackManifestVersion1_1, ArtifactTypeNotation, opts)
 }
 
 // signatureReferrers returns referrer nodes of desc in target filtered by
 // the "application/vnd.cncf.notary.signature" artifact type
 func signatureReferrers(ctx context.Context, target content.ReadOnlyGraphStorage, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) {
+	logger := log.GetLogger(ctx)
+
 	var results []ocispec.Descriptor
 	predecessors, err := target.Predecessors(ctx, desc)
 	if err != nil {
@@ -201,6 +213,7 @@ func signatureReferrers(ctx context.Context, target content.ReadOnlyGraphStorage
 			if err != nil {
 				return nil, err
 			}
+
 			var artifact artifactspec.Artifact
 			if err := json.Unmarshal(fetched, &artifact); err != nil {
 				return nil, err
@@ -208,6 +221,10 @@ func signatureReferrers(ctx context.Context, target content.ReadOnlyGraphStorage
 			if artifact.Subject == nil || !content.Equal(*artifact.Subject, desc) {
 				continue
 			}
+			if artifact.ArtifactType != ArtifactTypeNotation {
+				// not a valid Notary Project signature
+				continue
+			}
 			node.ArtifactType = artifact.ArtifactType
 			node.Annotations = artifact.Annotations
 		case ocispec.MediaTypeImageManifest:
@@ -218,6 +235,7 @@ func signatureReferrers(ctx context.Context, target content.ReadOnlyGraphStorage
 			if err != nil {
 				return nil, err
 			}
+
 			var image ocispec.Manifest
 			if err := json.Unmarshal(fetched, &image); err != nil {
 				return nil, err
@@ -225,15 +243,39 @@ func signatureReferrers(ctx context.Context, target content.ReadOnlyGraphStorage
 			if image.Subject == nil || !content.Equal(*image.Subject, desc) {
 				continue
 			}
-			node.ArtifactType = image.Config.MediaType
+
+			// check if image is a valid Notary Project signature
+			switch image.ArtifactType {
+			case ArtifactTypeNotation:
+				// 1. artifactType is "application/vnd.cncf.notary.signature",
+				// and config.mediaType is "application/vnd.oci.empty.v1+json"
+				if image.Config.MediaType == ocispec.MediaTypeEmptyJSON {
+					node.ArtifactType = image.ArtifactType
+				} else {
+					// not a valid Notary Project signature
+					logger.Warnf("not a valid Notary Project signature with artifactType %q, but config.mediaType is %q", image.ArtifactType, image.Config.MediaType)
+					continue
+				}
+			case "":
+				// 2. artifacteType does not exist,
+				// and config.mediaType is "application/vnd.cncf.notary.signature"
+				if image.Config.MediaType == ArtifactTypeNotation {
+					node.ArtifactType = image.Config.MediaType
+				} else {
+					// not a valid Notary Project signature
+					continue
+				}
+			default:
+				// not a valid Notary Project signature
+				continue
+			}
 			node.Annotations = image.Annotations
 		default:
 			continue
 		}
-		// only keep nodes of "application/vnd.cncf.notary.signature"
-		if node.ArtifactType == ArtifactTypeNotation {
-			results = append(results, node)
-		}
+
+		// add the node to results
+		results = append(results, node)
 	}
 	return results, nil
 }

registry/repository_test.go

@@ -1,8 +1,22 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package registry
 
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -10,21 +24,26 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"strings"
 	"testing"
 
 	"github.com/notaryproject/notation-go/internal/envelope"
+	"github.com/notaryproject/notation-go/internal/mock/ocilayout"
 	"github.com/notaryproject/notation-go/internal/slices"
 	"github.com/notaryproject/notation-go/registry/internal/artifactspec"
 	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"oras.land/oras-go/v2/content"
+	"oras.land/oras-go/v2/content/memory"
+	"oras.land/oras-go/v2/content/oci"
 	"oras.land/oras-go/v2/registry"
 	"oras.land/oras-go/v2/registry/remote"
 )
 
 const (
 	zeroDigest               = "sha256:0000000000000000000000000000000000000000000000000000000000000000"
+	emptyConfigDigest        = "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a"
 	validDigest              = "6c3c624b58dbbcd3c0dd82b4c53f04194d1247c6eebdaab7c610cf7d66709b3b"
 	validDigest2             = "1834876dcfb05cb167a5c24953eba58c4ac89b1adf57f28f2f9d09af107ee8f2"
 	invalidDigest            = "invaliddigest"
@@ -48,7 +67,7 @@ const (
 	{
 		"Manifests": [
 			{	
-				"MediaType": "application/vnd.oci.artifact.manifest.v1+json",
+				"MediaType": "application/vnd.oci.image.manifest.v1+json",
 				"Digest": "sha256:cf2a0974295fc17b8351ef52abae2f40212e20e0359ea980ec5597bb0315347b",
 				"Size": 620,
 				"ArtifactType": "application/vnd.cncf.notary.signature"
@@ -116,8 +135,13 @@ func (c mockRemoteClient) Do(req *http.Request) (*http.Response, error) {
 				"Docker-Content-Digest": {validDigestWithAlgo2},
 			},
 		}, nil
+	case "/v2/test/blobs/" + emptyConfigDigest:
+		return &http.Response{
+			StatusCode: http.StatusNotFound,
+			Body:       io.NopCloser(bytes.NewReader([]byte{})),
+		}, nil
 	case "/v2/test/manifests/" + invalidDigest:
-		return &http.Response{}, fmt.Errorf(errMsg)
+		return &http.Response{}, errors.New(errMsg)
 	case "v2/test/manifest/" + validDigest2:
 		return &http.Response{
 			StatusCode: http.StatusOK,
@@ -141,21 +165,39 @@ func (c mockRemoteClient) Do(req *http.Request) (*http.Response, error) {
 				},
 			}, nil
 		default:
-			return &http.Response{}, fmt.Errorf(msg)
+			return &http.Response{}, errors.New(msg)
 		}
 	case "/v2/test/referrers/":
 		return &http.Response{
 			StatusCode: http.StatusOK,
-			Body:       io.NopCloser(bytes.NewReader([]byte(validPage))),
+			Header: http.Header{
+				"Content-Type": []string{ocispec.MediaTypeImageIndex},
+			},
+			Body: io.NopCloser(bytes.NewReader([]byte(validPage))),
 			Request: &http.Request{
 				Method: "GET",
 				URL:    &url.URL{Path: "/v2/test/referrers/"},
 			},
 		}, nil
+	case "/v2/test/referrers/" + validDigestWithAlgo:
+		return &http.Response{
+			StatusCode: http.StatusOK,
+			Header: http.Header{
+				"Content-Type": []string{ocispec.MediaTypeImageIndex},
+			},
+			Body: io.NopCloser(bytes.NewReader([]byte(validPage))),
+			Request: &http.Request{
+				Method: "GET",
+				URL:    &url.URL{Path: "/v2/test/referrers/" + validDigestWithAlgo},
+			},
+		}, nil
 	case "/v2/test/referrers/" + zeroDigest:
 		return &http.Response{
 			StatusCode: http.StatusOK,
-			Body:       io.NopCloser(bytes.NewReader([]byte(validPageImage))),
+			Header: http.Header{
+				"Content-Type": []string{ocispec.MediaTypeImageIndex},
+			},
+			Body: io.NopCloser(bytes.NewReader([]byte(validPageImage))),
 			Request: &http.Request{
 				Method: "GET",
 				URL:    &url.URL{Path: "/v2/test/referrers/" + zeroDigest},
@@ -169,15 +211,17 @@ func (c mockRemoteClient) Do(req *http.Request) (*http.Response, error) {
 	default:
 		_, digest, found := strings.Cut(req.URL.Path, "/v2/test/manifests/")
 		if found && !slices.Contains(validDigestWithAlgoSlice, digest) {
-			return &http.Response{
+			resp := &http.Response{
 				StatusCode: http.StatusCreated,
 				Body:       io.NopCloser(bytes.NewReader([]byte(msg))),
-				Header: map[string][]string{
-					"Content-Type": {joseTag},
+				Header: http.Header{
+					"Content-Type": []string{joseTag},
+					"Oci-Subject":  []string{validDigestWithAlgo},
 				},
-			}, nil
+			}
+			return resp, nil
 		}
-		return &http.Response{}, fmt.Errorf(errMsg)
+		return &http.Response{}, errors.New(errMsg)
 	}
 }
 
@@ -288,16 +332,24 @@ func TestListSignatures(t *testing.T) {
 				reference:    validReference,
 				remoteClient: mockRemoteClient{},
 				plainHttp:    false,
+				artifactManifestDesc: ocispec.Descriptor{
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Digest:    validDigestWithAlgo,
+					Size:      481,
+				},
 			},
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			args := tt.args
-			ref, _ := registry.ParseReference(args.reference)
+			ref, err := registry.ParseReference(args.reference)
+			if err != nil {
+				t.Fatal(err)
+			}
 			client := newRepositoryClient(args.remoteClient, ref, args.plainHttp)
 
-			err := client.ListSignatures(args.ctx, args.artifactManifestDesc, func(signatureManifests []ocispec.Descriptor) error {
+			err = client.ListSignatures(args.ctx, args.artifactManifestDesc, func(signatureManifests []ocispec.Descriptor) error {
 				if len(signatureManifests) != 1 {
 					return fmt.Errorf("length of signatureManifests expected 1, got %d", len(signatureManifests))
 				}
@@ -348,6 +400,11 @@ func TestPushSignature(t *testing.T) {
 				signature:          signature,
 				ctx:                context.Background(),
 				remoteClient:       mockRemoteClient{},
+				subjectManifest: ocispec.Descriptor{
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Digest:    validDigestWithAlgo,
+					Size:      481,
+				},
 				annotations: map[string]string{
 					envelope.AnnotationX509ChainThumbprint: "[\"9f5f5aecee24b5cfdc7a91f6d5ac5c3a5348feb17c934d403f59ac251549ea0d\"]",
 				},
@@ -412,7 +469,6 @@ func newRepositoryClientWithImageManifest(client remote.Client, ref registry.Ref
 }
 
 var (
-	ociLayoutPath      = filepath.FromSlash("../internal/testdata/oci-layout")
 	reference          = "sha256:19dbd2e48e921426ee8ace4dc892edfb2ecdc1d1a72d5416c83670c30acecef0"
 	expectedTargetDesc = ocispec.Descriptor{
 		MediaType: "application/vnd.oci.image.manifest.v1+json",
@@ -425,8 +481,8 @@ var (
 	}
 	expectedSignatureManifestDesc = ocispec.Descriptor{
 		MediaType: "application/vnd.oci.image.manifest.v1+json",
-		Digest:    "sha256:baeaea44f55c94499b7e082bd3c98ad5ec40fdf23ef89cdf4e5db6b83e4f18f5",
-		Size:      728,
+		Digest:    "sha256:64300ad03f1dcd18136787363f3069c9598623221cbe76e3233d35266b7973d6",
+		Size:      793,
 	}
 	expectedSignatureBlobDesc = ocispec.Descriptor{
 		MediaType: joseTag,
@@ -435,11 +491,23 @@ var (
 	}
 )
 
-func TestOciLayoutRepositoryResolveAndPush(t *testing.T) {
-	repo, err := NewOCIRepository(ociLayoutPath, RepositoryOptions{})
+func TestOciLayoutRepositoryPushAndFetch(t *testing.T) {
+	// create a temp OCI layout
+	ociLayoutTestdataPath, err := filepath.Abs(filepath.Join("..", "internal", "testdata", "oci-layout"))
+	if err != nil {
+		t.Fatalf("failed to get oci layout path: %v", err)
+	}
+
+	newOCILayoutPath := t.TempDir()
+	if err := ocilayout.Copy(ociLayoutTestdataPath, newOCILayoutPath, "v2"); err != nil {
+		t.Fatalf("failed to create temp oci layout: %v", err)
+	}
+	repo, err := NewOCIRepository(newOCILayoutPath, RepositoryOptions{})
 	if err != nil {
 		t.Fatalf("failed to create oci.Store as registry.Repository: %v", err)
 	}
+
+	// test resolve
 	targetDesc, err := repo.Resolve(context.Background(), reference)
 	if err != nil {
 		t.Fatalf("failed to resolve reference: %v", err)
@@ -447,59 +515,515 @@ func TestOciLayoutRepositoryResolveAndPush(t *testing.T) {
 	if !content.Equal(targetDesc, expectedTargetDesc) {
 		t.Fatalf("failed to resolve reference. expected descriptor: %v, but got: %v", expectedTargetDesc, targetDesc)
 	}
-	signature, err := os.ReadFile(signaturePath)
-	if err != nil {
-		t.Fatalf("failed to read signature: %v", err)
-	}
-	_, signatureManifestDesc, err := repo.PushSignature(context.Background(), joseTag, signature, targetDesc, annotations)
-	if err != nil {
-		t.Fatalf("failed to push signature: %v", err)
-	}
-	if !content.Equal(expectedSignatureManifestDesc, signatureManifestDesc) {
-		t.Fatalf("expected desc: %v, got: %v", expectedSignatureManifestDesc, signatureManifestDesc)
-	}
-	expectedAnnotations := map[string]string{
-		envelope.AnnotationX509ChainThumbprint: "[\"9f5f5aecee24b5cfdc7a91f6d5ac5c3a5348feb17c934d403f59ac251549ea0d\"]",
-		ocispec.AnnotationCreated:              "2023-03-14T08:10:02Z",
-	}
-	if !reflect.DeepEqual(expectedAnnotations, signatureManifestDesc.Annotations) {
-		t.Fatalf("expected annotations: %v, but got: %v", expectedAnnotations, signatureManifestDesc.Annotations)
-	}
+
+	t.Run("oci layout push", func(t *testing.T) {
+		signature, err := os.ReadFile(signaturePath)
+		if err != nil {
+			t.Fatalf("failed to read signature: %v", err)
+		}
+		_, signatureManifestDesc, err := repo.PushSignature(context.Background(), joseTag, signature, targetDesc, annotations)
+		if err != nil {
+			t.Fatalf("failed to push signature: %v", err)
+		}
+		if !content.Equal(expectedSignatureManifestDesc, signatureManifestDesc) {
+			t.Fatalf("expected desc: %v, got: %v", expectedSignatureManifestDesc, signatureManifestDesc)
+		}
+		expectedAnnotations := map[string]string{
+			envelope.AnnotationX509ChainThumbprint: "[\"9f5f5aecee24b5cfdc7a91f6d5ac5c3a5348feb17c934d403f59ac251549ea0d\"]",
+			ocispec.AnnotationCreated:              "2023-03-14T08:10:02Z",
+		}
+		if !reflect.DeepEqual(expectedAnnotations, signatureManifestDesc.Annotations) {
+			t.Fatalf("expected annotations: %v, but got: %v", expectedAnnotations, signatureManifestDesc.Annotations)
+		}
+	})
+
+	t.Run("oci layout fetch", func(t *testing.T) {
+		err = repo.ListSignatures(context.Background(), targetDesc, func(signatureManifests []ocispec.Descriptor) error {
+			if len(signatureManifests) == 0 {
+				return fmt.Errorf("expected to find signature in the OCI layout folder, but got none")
+			}
+			var found bool
+			for _, sigManifestDesc := range signatureManifests {
+				if !content.Equal(sigManifestDesc, expectedSignatureManifestDesc) {
+					continue
+				}
+				_, sigDesc, err := repo.FetchSignatureBlob(context.Background(), sigManifestDesc)
+				if err != nil {
+					return fmt.Errorf("failed to fetch blob: %w", err)
+				}
+				if !content.Equal(expectedSignatureBlobDesc, sigDesc) {
+					return fmt.Errorf("expected to get signature blob desc: %v, got: %v", expectedSignatureBlobDesc, sigDesc)
+				}
+				found = true
+			}
+			if !found {
+				return fmt.Errorf("expected to find the signature with manifest desc: %v, but failed", expectedSignatureManifestDesc)
+			}
+			return nil
+		})
+		if err != nil {
+			t.Fatal(err)
+		}
+	})
 }
 
-func TestOciLayoutRepositoryListAndFetchBlob(t *testing.T) {
-	repo, err := NewOCIRepository(ociLayoutPath, RepositoryOptions{})
+func TestNewRepository(t *testing.T) {
+	target, err := oci.New(t.TempDir())
 	if err != nil {
 		t.Fatalf("failed to create oci.Store as registry.Repository: %v", err)
 	}
-	targetDesc, err := repo.Resolve(context.Background(), reference)
-	if err != nil {
-		t.Fatalf("failed to resolve reference: %v", err)
+	repo := NewRepository(target)
+	if repo == nil {
+		t.Fatalf("failed to create repository")
 	}
-	err = repo.ListSignatures(context.Background(), targetDesc, func(signatureManifests []ocispec.Descriptor) error {
-		if len(signatureManifests) == 0 {
-			return fmt.Errorf("expected to find signature in the OCI layout folder, but got none")
-		}
-		var found bool
-		for _, sigManifestDesc := range signatureManifests {
-			if !content.Equal(sigManifestDesc, expectedSignatureManifestDesc) {
-				continue
-			}
-			_, sigDesc, err := repo.FetchSignatureBlob(context.Background(), sigManifestDesc)
-			if err != nil {
-				return fmt.Errorf("failed to fetch blob: %w", err)
-			}
-			if !content.Equal(expectedSignatureBlobDesc, sigDesc) {
-				return fmt.Errorf("expected to get signature blob desc: %v, got: %v", expectedSignatureBlobDesc, sigDesc)
-			}
-			found = true
-		}
-		if !found {
-			return fmt.Errorf("expected to find the signature with manifest desc: %v, but failed", expectedSignatureManifestDesc)
-		}
-		return nil
-	})
-	if err != nil {
-		t.Fatal(err)
+	repoClient, ok := repo.(*repositoryClient)
+	if !ok {
+		t.Fatalf("failed to create repositoryClient")
+	}
+	if target != repoClient.GraphTarget {
+		t.Fatalf("expected target: %v, got: %v", target, repoClient.GraphTarget)
+	}
+}
+
+func TestNewOCIRepositoryFailed(t *testing.T) {
+	t.Run("os stat failed", func(t *testing.T) {
+		_, err := NewOCIRepository("invalid-path", RepositoryOptions{})
+		if err == nil {
+			t.Fatalf("expected to fail with invalid path")
+		}
+	})
+
+	t.Run("path is regular file", func(t *testing.T) {
+		// create a regular file in the temp dir
+		filePath := filepath.Join(t.TempDir(), "file")
+		file, err := os.Create(filePath)
+		if err != nil {
+			t.Fatalf("failed to create file: %v", err)
+		}
+		file.Close()
+
+		_, err = NewOCIRepository(filePath, RepositoryOptions{})
+		if err == nil {
+			t.Fatalf("expected to fail with regular file")
+		}
+	})
+
+	t.Run("no permission to create new path", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+		// create a directory in the temp dir
+		dirPath := filepath.Join(t.TempDir(), "dir")
+		err := os.Mkdir(dirPath, 0000)
+		if err != nil {
+			t.Fatalf("failed to create dir: %v", err)
+		}
+
+		_, err = NewOCIRepository(dirPath, RepositoryOptions{})
+		if err == nil {
+			t.Fatalf("expected to fail with no permission to create new path")
+		}
+	})
+}
+
+// testStorage implements content.ReadOnlyGraphStorage
+type testStorage struct {
+	store             *memory.Store
+	FetchError        error
+	FetchContent      []byte
+	PredecessorsError error
+	PredecessorsDesc  []ocispec.Descriptor
+}
+
+func (s *testStorage) Push(ctx context.Context, expected ocispec.Descriptor, reader io.Reader) error {
+	return s.store.Push(ctx, expected, reader)
+}
+
+func (s *testStorage) Fetch(ctx context.Context, target ocispec.Descriptor) (io.ReadCloser, error) {
+	if s.FetchError != nil {
+		return nil, s.FetchError
+	}
+	return io.NopCloser(bytes.NewReader(s.FetchContent)), nil
+}
+
+func (s *testStorage) Exists(ctx context.Context, target ocispec.Descriptor) (bool, error) {
+	return s.store.Exists(ctx, target)
+}
+
+func (s *testStorage) Predecessors(ctx context.Context, node ocispec.Descriptor) ([]ocispec.Descriptor, error) {
+	if s.PredecessorsError != nil {
+		return nil, s.PredecessorsError
+	}
+	return s.PredecessorsDesc, nil
+}
+
+func TestSignatureReferrers(t *testing.T) {
+	t.Run("get predecessors failed", func(t *testing.T) {
+		store := &testStorage{
+			store:             &memory.Store{},
+			PredecessorsError: fmt.Errorf("failed to get predecessors"),
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{})
+		if err == nil {
+			t.Fatalf("expected to fail with getting predecessors")
+		}
+	})
+
+	t.Run("artifact manifest exceds max blob size", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    validDigestWithAlgo2,
+					MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+					Size:      4*1024*1024 + 1,
+				},
+			},
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: validDigestWithAlgo2,
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with artifact manifest exceds max blob size")
+		}
+	})
+
+	t.Run("image manifest exceds max blob size", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    validDigestWithAlgo2,
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Size:      4*1024*1024 + 1,
+				},
+			},
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: validDigestWithAlgo2,
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with image manifest exceds max blob size")
+		}
+	})
+
+	t.Run("artifact manifest fetchAll failed", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    validDigestWithAlgo,
+					MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+					Size:      481,
+				},
+			},
+			FetchError: fmt.Errorf("failed to fetch all"),
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: validDigestWithAlgo,
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with fetchAll failed")
+		}
+	})
+
+	t.Run("image manifest fetchAll failed", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    validDigestWithAlgo,
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Size:      481,
+				},
+			},
+			FetchError: fmt.Errorf("failed to fetch all"),
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: validDigestWithAlgo,
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with fetchAll failed")
+		}
+	})
+
+	t.Run("artifact manifest marshal failed", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    "sha256:24aafc739daae02bcd33471a1b28bcfaaef0bb5e530ef44cd4e5d2445e606690",
+					MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+					Size:      15,
+				},
+			},
+			FetchContent: []byte("invalid content"),
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: "sha256:24aafc739daae02bcd33471a1b28bcfaaef0bb5e530ef44cd4e5d2445e606690",
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with marshal failed")
+		}
+	})
+
+	t.Run("image manifest marshal failed", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    "sha256:24aafc739daae02bcd33471a1b28bcfaaef0bb5e530ef44cd4e5d2445e606690",
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Size:      15,
+				},
+			},
+			FetchContent: []byte("invalid content"),
+		}
+		_, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: "sha256:24aafc739daae02bcd33471a1b28bcfaaef0bb5e530ef44cd4e5d2445e606690",
+		})
+		if err == nil {
+			t.Fatalf("expected to fail with marshal failed")
+		}
+	})
+
+	t.Run("no valid artifact manifest", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+					MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+					Size:      2,
+				},
+			},
+			FetchContent: []byte("{}"),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+		})
+
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatalf("expected to get no referrers, but got: %v", descriptors)
+		}
+	})
+
+	t.Run("artifact manifest with invalid artifactType", func(t *testing.T) {
+		sigManifest := `{"artifactType":"invalid", "subject":{"mediaType":"application/vnd.oci.artifact.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:835c3386406350fbddf5ee376b358bd20c6c423d6becbec166f83c533e4df5d6",
+			MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+			Size:      198,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.artifact.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatalf("expected to get no referrers, but got: %v", descriptors)
+		}
+	})
+
+	t.Run("no valid image manifest", func(t *testing.T) {
+		store := &testStorage{
+			store: &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{
+				{
+					Digest:    "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+					MediaType: "application/vnd.oci.image.manifest.v1+json",
+					Size:      2,
+				},
+			},
+			FetchContent: []byte("{}"),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest: "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatalf("expected to get no referrers, but got: %v", descriptors)
+		}
+	})
+
+	t.Run("image manifest with invalid mediaType", func(t *testing.T) {
+		sigManifest := `{}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "invalid",
+			Size:      2,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatal("expected length of descriptors to be 0")
+		}
+	})
+
+	t.Run("image manifest with valid artifactType and config.MediaType", func(t *testing.T) {
+		sigManifest := `{"artifactType":"application/vnd.cncf.notary.signature","config":{"mediaType":"application/vnd.oci.empty.v1+json"},"subject":{"mediaType":"application/vnd.oci.image.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:ad3ab7874c72d7bf5db0e55ce839b37ee71320bf7c18ac1a512600963f03c54d",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      283,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 1 {
+			t.Fatal("expected length of descriptors to be 1")
+		}
+		if !content.Equal(sigManifestDesc, descriptors[0]) {
+			t.Fatalf("expected %v, got: %v", sigManifestDesc, descriptors[0])
+		}
+	})
+
+	t.Run("image manifest with valid artifactType but invalid config.MediaType", func(t *testing.T) {
+		sigManifest := `{"artifactType":"application/vnd.cncf.notary.signature","config":{"mediaType":"invalid"},"subject":{"mediaType":"application/vnd.oci.image.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:becfe1975b40352d0c7bd1337707a4c471fdcfa1ac380f2875fe8076a3bc3581",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      257,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatal("expected length of descriptors to be 0")
+		}
+	})
+
+	t.Run("image manifest with no artifactType and valid config.MediaType", func(t *testing.T) {
+		sigManifest := `{"config":{"mediaType":"application/vnd.cncf.notary.signature"},"subject":{"mediaType":"application/vnd.oci.image.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:0e0be61f687ba634dd772f6d3048101f78f22fabda64cc9600671cee41ab2d47",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      232,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 1 {
+			t.Fatal("expected length of descriptors to be 1")
+		}
+		if !content.Equal(sigManifestDesc, descriptors[0]) {
+			t.Fatalf("expected %v, got: %v", sigManifestDesc, descriptors[0])
+		}
+	})
+
+	t.Run("image manifest with no artifactType and invalid config.MediaType", func(t *testing.T) {
+		sigManifest := `{"config":{"mediaType":"invalid"},"subject":{"mediaType":"application/vnd.oci.image.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:1580e4f590269bd40a33e902888429c9bbb250902f5a7eb50f04fbb8bd4dbab3",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      202,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatal("expected length of descriptors to be 0")
+		}
+	})
+
+	t.Run("image manifest with invalid artifactType", func(t *testing.T) {
+		sigManifest := `{"artifactType":"invalid","config":{"mediaType":"application/vnd.oci.empty.v1+json"},"subject":{"mediaType":"application/vnd.oci.image.manifest.v1+json","digest":"sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a","size":2}}`
+		sigManifestDesc := ocispec.Descriptor{
+			Digest:    "sha256:d8c225cb4eca3e15fa2a44c9d302044e8c8683399939e26f417edb82f8b69cc3",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      253,
+		}
+		store := &testStorage{
+			store:            &memory.Store{},
+			PredecessorsDesc: []ocispec.Descriptor{sigManifestDesc},
+			FetchContent:     []byte(sigManifest),
+		}
+		descriptors, err := signatureReferrers(context.Background(), store, ocispec.Descriptor{
+			Digest:    "sha256:sha256:44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a",
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+			Size:      2,
+		})
+		if err != nil {
+			t.Fatalf("failed to get referrers: %v", err)
+		}
+		if len(descriptors) != 0 {
+			t.Fatal("expected length of descriptors to be 0")
+		}
+	})
+}
+
+func TestUploadSignatureManifest(t *testing.T) {
+	ref, err := registry.ParseReference(validReference)
+	if err != nil {
+		t.Fatalf("failed to parse reference")
+	}
+	client := newRepositoryClientWithImageManifest(mockRemoteClient{}, ref, false)
+	manifest, err := client.uploadSignatureManifest(context.Background(),
+		ocispec.Descriptor{}, ocispec.Descriptor{}, nil)
+	if err != nil {
+		t.Fatalf("failed to upload signature manifest: %v", err)
+	}
+	if manifest.ArtifactType != ArtifactTypeNotation {
+		t.Fatalf("expected artifact type: %s, got: %s", ArtifactTypeNotation, manifest.ArtifactType)
 	}
 }

signer/plugin.go

@@ -1,44 +1,76 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package signer
 
 import (
 	"context"
+	"crypto"
 	"crypto/x509"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"time"
 
+	"oras.land/oras-go/v2/content"
+
 	"github.com/notaryproject/notation-core-go/signature"
 	"github.com/notaryproject/notation-go"
 	"github.com/notaryproject/notation-go/internal/envelope"
 	"github.com/notaryproject/notation-go/log"
-	"github.com/notaryproject/notation-go/plugin"
 	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/notaryproject/notation-plugin-framework-go/plugin"
+	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
-	"oras.land/oras-go/v2/content"
 )
 
-// pluginSigner signs artifacts and generates signatures.
-// It implements notation.Signer
-type pluginSigner struct {
+// PluginSigner signs artifacts and generates signatures.
+//
+// It implements [notation.Signer] and [notation.BlobSigner].
+type PluginSigner struct {
 	plugin              plugin.SignPlugin
 	keyID               string
 	pluginConfig        map[string]string
 	manifestAnnotations map[string]string
 }
 
-// NewFromPlugin creates a notation.Signer that signs artifacts and generates
+var algorithms = map[crypto.Hash]digest.Algorithm{
+	crypto.SHA256: digest.SHA256,
+	crypto.SHA384: digest.SHA384,
+	crypto.SHA512: digest.SHA512,
+}
+
+// NewFromPlugin creates a [PluginSigner] that signs artifacts and generates
 // signatures by delegating the one or more operations to the named plugin,
 // as defined in https://github.com/notaryproject/notaryproject/blob/main/specs/plugin-extensibility.md#signing-interfaces.
-func NewFromPlugin(plugin plugin.Plugin, keyID string, pluginConfig map[string]string) (notation.Signer, error) {
+//
+// Deprecated: NewFromPlugin function exists for historical compatibility and
+// should not be used. To create [PluginSigner], use NewPluginSigner() function.
+func NewFromPlugin(plugin plugin.SignPlugin, keyID string, pluginConfig map[string]string) (notation.Signer, error) {
+	return NewPluginSigner(plugin, keyID, pluginConfig)
+}
+
+// NewPluginSigner creates a [PluginSigner] that signs artifacts and generates
+// signatures by delegating the one or more operations to the named plugin,
+// as defined in https://github.com/notaryproject/notaryproject/blob/main/specs/plugin-extensibility.md#signing-interfaces.
+func NewPluginSigner(plugin plugin.SignPlugin, keyID string, pluginConfig map[string]string) (*PluginSigner, error) {
 	if plugin == nil {
 		return nil, errors.New("nil plugin")
 	}
 	if keyID == "" {
 		return nil, errors.New("keyID not specified")
 	}
-
-	return &pluginSigner{
+	return &PluginSigner{
 		plugin:       plugin,
 		keyID:        keyID,
 		pluginConfig: pluginConfig,
@@ -46,66 +78,103 @@ func NewFromPlugin(plugin plugin.Plugin, keyID string, pluginConfig map[string]s
 }
 
 // PluginAnnotations returns signature manifest annotations returned from plugin
-func (s *pluginSigner) PluginAnnotations() map[string]string {
+func (s *PluginSigner) PluginAnnotations() map[string]string {
 	return s.manifestAnnotations
 }
 
 // Sign signs the artifact described by its descriptor and returns the
-// marshalled envelope.
-func (s *pluginSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+// signature and SignerInfo.
+func (s *PluginSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	logger := log.GetLogger(ctx)
+	mergedConfig := s.mergeConfig(opts.PluginConfig)
 	logger.Debug("Invoking plugin's get-plugin-metadata command")
-	req := &proto.GetMetadataRequest{
-		PluginConfig: s.mergeConfig(opts.PluginConfig),
-	}
-	metadata, err := s.plugin.GetMetadata(ctx, req)
+	metadata, err := s.plugin.GetMetadata(ctx, &plugin.GetMetadataRequest{PluginConfig: mergedConfig})
 	if err != nil {
 		return nil, nil, err
 	}
-
-	logger.Debugf("Using plugin %v with capabilities %v to sign artifact %v in signature media type %v", metadata.Name, metadata.Capabilities, desc.Digest, opts.SignatureMediaType)
-	if metadata.HasCapability(proto.CapabilitySignatureGenerator) {
-		return s.generateSignature(ctx, desc, opts, metadata)
-	} else if metadata.HasCapability(proto.CapabilityEnvelopeGenerator) {
-		return s.generateSignatureEnvelope(ctx, desc, opts)
+	logger.Debugf("Using plugin %v with capabilities %v to sign oci artifact %v in signature media type %v", metadata.Name, metadata.Capabilities, desc.Digest, opts.SignatureMediaType)
+	if metadata.HasCapability(plugin.CapabilitySignatureGenerator) {
+		ks, err := s.getKeySpec(ctx, mergedConfig)
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to sign with the plugin %s: %w", metadata.Name, err)
+		}
+		sig, signerInfo, err := s.generateSignature(ctx, desc, opts, ks, metadata, mergedConfig)
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to sign with the plugin %s: %w", metadata.Name, err)
+		}
+		return sig, signerInfo, nil
+	} else if metadata.HasCapability(plugin.CapabilityEnvelopeGenerator) {
+		sig, signerInfo, err := s.generateSignatureEnvelope(ctx, desc, opts)
+		if err != nil {
+			return nil, nil, fmt.Errorf("failed to sign with the plugin %s: %w", metadata.Name, err)
+		}
+		return sig, signerInfo, nil
 	}
 	return nil, nil, fmt.Errorf("plugin does not have signing capabilities")
 }
 
-func (s *pluginSigner) generateSignature(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions, metadata *proto.GetMetadataResponse) ([]byte, *signature.SignerInfo, error) {
+// SignBlob signs the descriptor returned by genDesc, and returns the
+// signature and SignerInfo.
+func (s *PluginSigner) SignBlob(ctx context.Context, descGenFunc notation.BlobDescriptorGenerator, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+	logger := log.GetLogger(ctx)
+	mergedConfig := s.mergeConfig(opts.PluginConfig)
+	logger.Debug("Invoking plugin's get-plugin-metadata command")
+	metadata, err := s.plugin.GetMetadata(ctx, &plugin.GetMetadataRequest{PluginConfig: mergedConfig})
+	if err != nil {
+		return nil, nil, err
+	}
+	// only support blob signing with the signature generator capability because
+	// the envelope generator capability is designed for OCI signing.
+	// A new capability may be added in the future for blob signing.
+	if !metadata.HasCapability(plugin.CapabilitySignatureGenerator) {
+		return nil, nil, fmt.Errorf("the plugin %q lacks the signature generator capability required for blob signing", metadata.Name)
+	}
+
+	logger.Debug("Invoking plugin's describe-key command")
+	ks, err := s.getKeySpec(ctx, mergedConfig)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// get descriptor to sign
+	desc, err := getDescriptor(ks, descGenFunc)
+	if err != nil {
+		return nil, nil, err
+	}
+	logger.Debugf("Using plugin %v with capabilities %v to sign blob using descriptor %+v", metadata.Name, metadata.Capabilities, desc)
+	return s.generateSignature(ctx, desc, opts, ks, metadata, mergedConfig)
+}
+
+func (s *PluginSigner) getKeySpec(ctx context.Context, config map[string]string) (signature.KeySpec, error) {
+	logger := log.GetLogger(ctx)
+	logger.Debug("Invoking plugin's describe-key command")
+	descKeyResp, err := s.describeKey(ctx, config)
+	if err != nil {
+		return signature.KeySpec{}, err
+	}
+	if s.keyID != descKeyResp.KeyID {
+		return signature.KeySpec{}, fmt.Errorf("keyID in describeKey response %q does not match request %q", descKeyResp.KeyID, s.keyID)
+	}
+	return proto.DecodeKeySpec(descKeyResp.KeySpec)
+}
+
+func (s *PluginSigner) generateSignature(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions, ks signature.KeySpec, metadata *plugin.GetMetadataResponse, pluginConfig map[string]string) ([]byte, *signature.SignerInfo, error) {
 	logger := log.GetLogger(ctx)
 	logger.Debug("Generating signature by plugin")
-	config := s.mergeConfig(opts.PluginConfig)
-	// Get key info.
-	key, err := s.describeKey(ctx, config)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	// Check keyID is honored.
-	if s.keyID != key.KeyID {
-		return nil, nil, fmt.Errorf("keyID in describeKey response %q does not match request %q", key.KeyID, s.keyID)
-	}
-	ks, err := proto.DecodeKeySpec(key.KeySpec)
-	if err != nil {
-		return nil, nil, err
-	}
-
-	genericSigner := genericSigner{
-		Signer: &pluginPrimitiveSigner{
+	genericSigner := GenericSigner{
+		signer: &pluginPrimitiveSigner{
 			ctx:          ctx,
 			plugin:       s.plugin,
 			keyID:        s.keyID,
-			pluginConfig: config,
+			pluginConfig: pluginConfig,
 			keySpec:      ks,
 		},
 	}
-
 	opts.SigningAgent = fmt.Sprintf("%s %s/%s", signingAgent, metadata.Name, metadata.Version)
 	return genericSigner.Sign(ctx, desc, opts)
 }
 
-func (s *pluginSigner) generateSignatureEnvelope(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+func (s *PluginSigner) generateSignatureEnvelope(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	logger := log.GetLogger(ctx)
 	logger.Debug("Generating signature envelope by plugin")
 	payload := envelope.Payload{TargetArtifact: envelope.SanitizeTargetArtifact(desc)}
@@ -113,8 +182,10 @@ func (s *pluginSigner) generateSignatureEnvelope(ctx context.Context, desc ocisp
 	if err != nil {
 		return nil, nil, fmt.Errorf("envelope payload can't be marshalled: %w", err)
 	}
+
 	// Execute plugin sign command.
-	req := &proto.GenerateEnvelopeRequest{
+	req := &plugin.GenerateEnvelopeRequest{
+		ContractVersion:         plugin.ContractVersion,
 		KeyID:                   s.keyID,
 		Payload:                 payloadBytes,
 		SignatureEnvelopeType:   opts.SignatureMediaType,
@@ -134,13 +205,11 @@ func (s *pluginSigner) generateSignatureEnvelope(ctx context.Context, desc ocisp
 			resp.SignatureEnvelopeType, req.SignatureEnvelopeType,
 		)
 	}
-
 	logger.Debug("Verifying signature envelope generated by the plugin")
 	sigEnv, err := signature.ParseEnvelope(opts.SignatureMediaType, resp.SignatureEnvelope)
 	if err != nil {
 		return nil, nil, err
 	}
-
 	envContent, err := sigEnv.Verify()
 	if err != nil {
 		return nil, nil, fmt.Errorf("generated signature failed verification: %w", err)
@@ -148,31 +217,29 @@ func (s *pluginSigner) generateSignatureEnvelope(ctx context.Context, desc ocisp
 	if err := envelope.ValidatePayloadContentType(&envContent.Payload); err != nil {
 		return nil, nil, err
 	}
-
 	content := envContent.Payload.Content
 	var signedPayload envelope.Payload
 	if err = json.Unmarshal(content, &signedPayload); err != nil {
 		return nil, nil, fmt.Errorf("signed envelope payload can't be unmarshalled: %w", err)
 	}
-
 	if !isPayloadDescriptorValid(desc, signedPayload.TargetArtifact) {
 		return nil, nil, fmt.Errorf("during signing descriptor subject has changed from %+v to %+v", desc, signedPayload.TargetArtifact)
 	}
-
 	if unknownAttributes := areUnknownAttributesAdded(content); len(unknownAttributes) != 0 {
 		return nil, nil, fmt.Errorf("during signing, following unknown attributes were added to subject descriptor: %+q", unknownAttributes)
 	}
-
 	s.manifestAnnotations = resp.Annotations
 	return resp.SignatureEnvelope, &envContent.SignerInfo, nil
 }
 
-func (s *pluginSigner) mergeConfig(config map[string]string) map[string]string {
+func (s *PluginSigner) mergeConfig(config map[string]string) map[string]string {
 	c := make(map[string]string, len(s.pluginConfig)+len(config))
+
 	// First clone s.PluginConfig.
 	for k, v := range s.pluginConfig {
 		c[k] = v
 	}
+
 	// Then set or override entries from config.
 	for k, v := range config {
 		c[k] = v
@@ -180,16 +247,16 @@ func (s *pluginSigner) mergeConfig(config map[string]string) map[string]string {
 	return c
 }
 
-func (s *pluginSigner) describeKey(ctx context.Context, config map[string]string) (*proto.DescribeKeyResponse, error) {
-	req := &proto.DescribeKeyRequest{
-		KeyID:        s.keyID,
-		PluginConfig: config,
+func (s *PluginSigner) describeKey(ctx context.Context, config map[string]string) (*plugin.DescribeKeyResponse, error) {
+	req := &plugin.DescribeKeyRequest{
+		ContractVersion: plugin.ContractVersion,
+		KeyID:           s.keyID,
+		PluginConfig:    config,
 	}
 	resp, err := s.plugin.DescribeKey(ctx, req)
 	if err != nil {
-		return nil, fmt.Errorf("describe-key command failed: %w", err)
+		return nil, err
 	}
-
 	return resp, nil
 }
 
@@ -199,6 +266,7 @@ func isDescriptorSubset(original, newDesc ocispec.Descriptor) bool {
 	if !content.Equal(original, newDesc) {
 		return false
 	}
+
 	// Plugins may append additional annotations but not replace/override
 	// existing.
 	for k, v := range original.Annotations {
@@ -216,6 +284,7 @@ func isPayloadDescriptorValid(originalDesc, newDesc ocispec.Descriptor) bool {
 
 func areUnknownAttributesAdded(content []byte) []string {
 	var targetArtifactMap map[string]interface{}
+
 	// Ignoring error because we already successfully unmarshalled before this
 	// point
 	_ = json.Unmarshal(content, &targetArtifactMap)
@@ -272,23 +341,21 @@ func (s *pluginPrimitiveSigner) Sign(payload []byte) ([]byte, []*x509.Certificat
 	if err != nil {
 		return nil, nil, err
 	}
-
 	keySpecHash, err := proto.HashAlgorithmFromKeySpec(s.keySpec)
 	if err != nil {
 		return nil, nil, err
 	}
-
-	req := &proto.GenerateSignatureRequest{
-		KeyID:        s.keyID,
-		KeySpec:      keySpec,
-		Hash:         keySpecHash,
-		Payload:      payload,
-		PluginConfig: s.pluginConfig,
+	req := &plugin.GenerateSignatureRequest{
+		ContractVersion: plugin.ContractVersion,
+		KeyID:           s.keyID,
+		KeySpec:         keySpec,
+		Hash:            keySpecHash,
+		Payload:         payload,
+		PluginConfig:    s.pluginConfig,
 	}
-
 	resp, err := s.plugin.GenerateSignature(s.ctx, req)
 	if err != nil {
-		return nil, nil, fmt.Errorf("generate-signature command failed: %w", err)
+		return nil, nil, err
 	}
 
 	// Check keyID is honored.

signer/plugin_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package signer
 
 import (
@@ -19,6 +32,7 @@ import (
 	"github.com/notaryproject/notation-go/internal/envelope"
 	"github.com/notaryproject/notation-go/plugin"
 	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
@@ -57,6 +71,16 @@ type mockPlugin struct {
 	keySpec           signature.KeySpec
 }
 
+func getDescriptorFunc(throwError bool) func(hashAlgo digest.Algorithm) (ocispec.Descriptor, error) {
+	return func(hashAlgo digest.Algorithm) (ocispec.Descriptor, error) {
+		if throwError {
+			return ocispec.Descriptor{}, errors.New("")
+		}
+		return validSignDescriptor, nil
+	}
+
+}
+
 func newMockPlugin(key crypto.PrivateKey, certs []*x509.Certificate, keySpec signature.KeySpec) *mockPlugin {
 	return &mockPlugin{
 		key:     key,
@@ -102,7 +126,7 @@ func (p *mockPlugin) GenerateSignature(ctx context.Context, req *proto.GenerateS
 		return &proto.GenerateSignatureResponse{
 			KeyID:            req.KeyID,
 			Signature:        invalidSignatureEnvelope,
-			SigningAlgorithm: string(sigAlg),
+			SigningAlgorithm: sigAlg,
 			CertificateChain: certChain,
 		}, err
 	}
@@ -123,7 +147,7 @@ func (p *mockPlugin) GenerateSignature(ctx context.Context, req *proto.GenerateS
 
 // GenerateEnvelope generates the Envelope with signature based on the request.
 func (p *mockPlugin) GenerateEnvelope(ctx context.Context, req *proto.GenerateEnvelopeRequest) (*proto.GenerateEnvelopeResponse, error) {
-	internalPluginSigner := pluginSigner{
+	internalPluginSigner := PluginSigner{
 		plugin: newMockPlugin(p.key, p.certs, p.keySpec),
 	}
 
@@ -192,16 +216,46 @@ func (p *mockPlugin) GenerateEnvelope(ctx context.Context, req *proto.GenerateEn
 	return &proto.GenerateEnvelopeResponse{}, nil
 }
 
+func TestPluginSignerImpl(t *testing.T) {
+	p := &PluginSigner{}
+	if _, ok := interface{}(p).(notation.Signer); !ok {
+		t.Fatal("PluginSigner does not implement notation.Signer")
+	}
+
+	if _, ok := interface{}(p).(notation.BlobSigner); !ok {
+		t.Fatal("PluginSigner does not implement notation.BlobSigner")
+	}
+}
+
 func TestNewFromPluginFailed(t *testing.T) {
-	wantErr := "keyID not specified"
-	_, err := NewFromPlugin(&plugin.CLIPlugin{}, "", make(map[string]string))
-	if err == nil || err.Error() != wantErr {
-		t.Fatalf("TestNewFromPluginFailed expects error %q, got %q", wantErr, err.Error())
+	tests := map[string]struct {
+		pl     plugin.SignPlugin
+		keyID  string
+		errMsg string
+	}{
+		"Invalid KeyID": {
+			pl:     &plugin.CLIPlugin{},
+			keyID:  "",
+			errMsg: "keyID not specified",
+		},
+		"nilPlugin": {
+			pl:     nil,
+			keyID:  "someKeyId",
+			errMsg: "nil plugin",
+		},
+	}
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			_, err := NewFromPlugin(tc.pl, tc.keyID, make(map[string]string))
+			if err == nil || err.Error() != tc.errMsg {
+				t.Fatalf("TestNewFromPluginFailed expects error %q, got %q", tc.errMsg, err.Error())
+			}
+		})
 	}
 }
 
 func TestSigner_Sign_EnvelopeNotSupported(t *testing.T) {
-	signer := pluginSigner{
+	signer := PluginSigner{
 		plugin: newMockPlugin(nil, nil, signature.KeySpec{Type: signature.KeyTypeRSA, Size: 2048}),
 	}
 	opts := notation.SignerSignOptions{SignatureMediaType: "unsupported"}
@@ -212,7 +266,7 @@ func TestSigner_Sign_DescribeKeyIDMismatch(t *testing.T) {
 	respKeyId := ""
 	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
 		t.Run(fmt.Sprintf("envelopeType=%v", envelopeType), func(t *testing.T) {
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: newMockPlugin(nil, nil, signature.KeySpec{}),
 				keyID:  "1",
 			}
@@ -225,7 +279,7 @@ func TestSigner_Sign_ExpiryInValid(t *testing.T) {
 	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
 		t.Run(fmt.Sprintf("envelopeType=%v", envelopeType), func(t *testing.T) {
 			ks, _ := signature.ExtractKeySpec(keyCertPairCollections[0].certs[0])
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: newMockPlugin(keyCertPairCollections[0].key, keyCertPairCollections[0].certs, ks),
 			}
 			_, _, err := signer.Sign(context.Background(), ocispec.Descriptor{}, notation.SignerSignOptions{ExpiryDuration: -24 * time.Hour, SignatureMediaType: envelopeType})
@@ -242,7 +296,7 @@ func TestSigner_Sign_InvalidCertChain(t *testing.T) {
 		t.Run(fmt.Sprintf("envelopeType=%v", envelopeType), func(t *testing.T) {
 			mockPlugin := newMockPlugin(defaultKeyCert.key, defaultKeyCert.certs, defaultKeySpec)
 			mockPlugin.invalidCertChain = true
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: mockPlugin,
 			}
 			testSignerError(t, signer, "x509: malformed certificate", notation.SignerSignOptions{SignatureMediaType: envelopeType})
@@ -256,7 +310,7 @@ func TestSigner_Sign_InvalidDescriptor(t *testing.T) {
 			mockPlugin := newMockPlugin(defaultKeyCert.key, defaultKeyCert.certs, defaultKeySpec)
 			mockPlugin.wantEnvelope = true
 			mockPlugin.invalidDescriptor = true
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: mockPlugin,
 			}
 			testSignerError(t, signer, "during signing, following unknown attributes were added to subject descriptor: [\"additional_field\"]", notation.SignerSignOptions{SignatureMediaType: envelopeType})
@@ -269,7 +323,7 @@ func TestPluginSigner_Sign_SignatureVerifyError(t *testing.T) {
 		t.Run(fmt.Sprintf("envelopeType=%v", envelopeType), func(t *testing.T) {
 			mockPlugin := newMockPlugin(defaultKeyCert.key, defaultKeyCert.certs, defaultKeySpec)
 			mockPlugin.invalidSig = true
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: mockPlugin,
 			}
 			testSignerError(t, signer, "signature is invalid", notation.SignerSignOptions{SignatureMediaType: envelopeType})
@@ -282,15 +336,48 @@ func TestPluginSigner_Sign_Valid(t *testing.T) {
 		for _, keyCert := range keyCertPairCollections {
 			t.Run(fmt.Sprintf("external plugin,envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
 				keySpec, _ := proto.DecodeKeySpec(proto.KeySpec(keyCert.keySpecName))
-				pluginSigner := pluginSigner{
+				pluginSigner := PluginSigner{
 					plugin: newMockPlugin(keyCert.key, keyCert.certs, keySpec),
 				}
-				basicSignTest(t, &pluginSigner, envelopeType, &validMetadata)
+				validSignOpts.SignatureMediaType = envelopeType
+				data, signerInfo, err := pluginSigner.Sign(context.Background(), validSignDescriptor, validSignOpts)
+				basicSignTest(t, &pluginSigner, envelopeType, data, signerInfo, err)
 			})
 		}
 	}
 }
 
+func TestPluginSigner_SignBlob_Valid(t *testing.T) {
+	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
+		for _, keyCert := range keyCertPairCollections {
+			t.Run(fmt.Sprintf("external plugin,envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
+				keySpec, _ := proto.DecodeKeySpec(proto.KeySpec(keyCert.keySpecName))
+				pluginSigner := PluginSigner{
+					plugin: newMockPlugin(keyCert.key, keyCert.certs, keySpec),
+				}
+				validSignOpts.SignatureMediaType = envelopeType
+				data, signerInfo, err := pluginSigner.SignBlob(context.Background(), getDescriptorFunc(false), validSignOpts)
+				basicSignTest(t, &pluginSigner, envelopeType, data, signerInfo, err)
+			})
+		}
+	}
+}
+
+func TestPluginSigner_SignBlob_Invalid(t *testing.T) {
+	t.Run("blob signing with generate envelope plugin should fail", func(t *testing.T) {
+		plugin := &mockPlugin{}
+		plugin.wantEnvelope = true
+		pluginSigner := PluginSigner{
+			plugin: plugin,
+		}
+		_, _, err := pluginSigner.SignBlob(context.Background(), getDescriptorFunc(false), validSignOpts)
+		expectedErrMsg := "the plugin \"testPlugin\" lacks the signature generator capability required for blob signing"
+		if err == nil || !strings.Contains(err.Error(), expectedErrMsg) {
+			t.Fatalf("expected error %q, got %v", expectedErrMsg, err)
+		}
+	})
+}
+
 func TestPluginSigner_SignEnvelope_RunFailed(t *testing.T) {
 	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
 		t.Run(fmt.Sprintf("envelopeType=%v", envelopeType), func(t *testing.T) {
@@ -298,7 +385,7 @@ func TestPluginSigner_SignEnvelope_RunFailed(t *testing.T) {
 				wantEnvelope: true,
 				failEnvelope: true,
 			}
-			signer := pluginSigner{
+			signer := PluginSigner{
 				plugin: p,
 			}
 			testSignerError(t, signer, "failed GenerateEnvelope", notation.SignerSignOptions{SignatureMediaType: envelopeType})
@@ -313,10 +400,12 @@ func TestPluginSigner_SignEnvelope_Valid(t *testing.T) {
 				keySpec, _ := proto.DecodeKeySpec(proto.KeySpec(keyCert.keySpecName))
 				mockPlugin := newMockPlugin(keyCert.key, keyCert.certs, keySpec)
 				mockPlugin.wantEnvelope = true
-				pluginSigner := pluginSigner{
+				pluginSigner := PluginSigner{
 					plugin: mockPlugin,
 				}
-				basicSignTest(t, &pluginSigner, envelopeType, &validMetadata)
+				validSignOpts.SignatureMediaType = envelopeType
+				data, signerInfo, err := pluginSigner.Sign(context.Background(), validSignDescriptor, validSignOpts)
+				basicSignTest(t, &pluginSigner, envelopeType, data, signerInfo, err)
 			})
 		}
 	}
@@ -328,7 +417,7 @@ func TestPluginSigner_SignWithAnnotations_Valid(t *testing.T) {
 			t.Run(fmt.Sprintf("external plugin,envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
 				keySpec, _ := proto.DecodeKeySpec(proto.KeySpec(keyCert.keySpecName))
 				annts := map[string]string{"key": "value"}
-				pluginSigner := pluginSigner{
+				pluginSigner := PluginSigner{
 					plugin: &mockPlugin{
 						key:          keyCert.key,
 						certs:        keyCert.certs,
@@ -337,7 +426,9 @@ func TestPluginSigner_SignWithAnnotations_Valid(t *testing.T) {
 						wantEnvelope: true,
 					},
 				}
-				basicSignTest(t, &pluginSigner, envelopeType, &validMetadata)
+				validSignOpts.SignatureMediaType = envelopeType
+				data, signerInfo, err := pluginSigner.Sign(context.Background(), validSignDescriptor, validSignOpts)
+				basicSignTest(t, &pluginSigner, envelopeType, data, signerInfo, err)
 				if !reflect.DeepEqual(pluginSigner.PluginAnnotations(), annts) {
 					fmt.Println(pluginSigner.PluginAnnotations())
 					t.Errorf("mismatch in annotations returned from PluginAnnotations()")
@@ -347,7 +438,7 @@ func TestPluginSigner_SignWithAnnotations_Valid(t *testing.T) {
 	}
 }
 
-func testSignerError(t *testing.T, signer pluginSigner, wantEr string, opts notation.SignerSignOptions) {
+func testSignerError(t *testing.T, signer PluginSigner, wantEr string, opts notation.SignerSignOptions) {
 	t.Helper()
 	_, _, err := signer.Sign(context.Background(), ocispec.Descriptor{}, opts)
 	if err == nil || !strings.Contains(err.Error(), wantEr) {
@@ -355,9 +446,7 @@ func testSignerError(t *testing.T, signer pluginSigner, wantEr string, opts nota
 	}
 }
 
-func basicSignTest(t *testing.T, pluginSigner *pluginSigner, envelopeType string, metadata *proto.GetMetadataResponse) {
-	validSignOpts.SignatureMediaType = envelopeType
-	data, signerInfo, err := pluginSigner.Sign(context.Background(), validSignDescriptor, validSignOpts)
+func basicSignTest(t *testing.T, ps *PluginSigner, envelopeType string, data []byte, signerInfo *signature.SignerInfo, err error) {
 	if err != nil {
 		t.Fatalf("Signer.Sign() error = %v, wantErr nil", err)
 	}
@@ -386,12 +475,12 @@ func basicSignTest(t *testing.T, pluginSigner *pluginSigner, envelopeType string
 		TargetArtifact: validSignDescriptor,
 	}
 	if !reflect.DeepEqual(expectedPayload, gotPayload) {
-		t.Fatalf("Signer.Sign() descriptor subject changed, expect: %v, got: %v", expectedPayload, payload)
+		t.Fatalf("Signer.Sign() descriptor subject changed, expect: %+v, got: %+v", expectedPayload, payload)
 	}
 	if signerInfo.SignedAttributes.SigningScheme != signature.SigningSchemeX509 {
-		t.Fatalf("Signer.Sign() signing scheme changed, expect: %v, got: %v", signerInfo.SignedAttributes.SigningScheme, signature.SigningSchemeX509)
+		t.Fatalf("Signer.Sign() signing scheme changed, expect: %+v, got: %+v", signerInfo.SignedAttributes.SigningScheme, signature.SigningSchemeX509)
 	}
-	mockPlugin := pluginSigner.plugin.(*mockPlugin)
+	mockPlugin := ps.plugin.(*mockPlugin)
 	if mockPlugin.keySpec.SignatureAlgorithm() != signerInfo.SignatureAlgorithm {
 		t.Fatalf("Signer.Sign() signing algorithm changed")
 	}
@@ -401,5 +490,5 @@ func basicSignTest(t *testing.T, pluginSigner *pluginSigner, envelopeType string
 	if !reflect.DeepEqual(mockPlugin.certs, signerInfo.CertificateChain) {
 		t.Fatalf(" Signer.Sign() cert chain changed")
 	}
-	basicVerification(t, data, envelopeType, mockPlugin.certs[len(mockPlugin.certs)-1], metadata)
+	basicVerification(t, data, envelopeType, mockPlugin.certs[len(mockPlugin.certs)-1], &validMetadata)
 }

signer/signer.go

@@ -1,6 +1,19 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 // Package signer provides notation signing functionality. It implements the
-// notation.Signer interface by providing builtinSigner for local signing and
-// pluginSigner for remote signing.
+// [notation.Signer] and [notation.BlobSigner] interfaces by providing
+// builtinSigner for local signing and [PluginSigner] for remote signing.
 package signer
 
 import (
@@ -21,26 +34,42 @@ import (
 )
 
 // signingAgent is the unprotected header field used by signature.
-const signingAgent = "Notation/1.0.0"
+const signingAgent = "notation-go/1.3.0+unreleased"
 
-// genericSigner implements notation.Signer and embeds signature.Signer
-type genericSigner struct {
-	signature.Signer
+// GenericSigner implements [notation.Signer] and [notation.BlobSigner].
+// It embeds signature.Signer.
+type GenericSigner struct {
+	signer signature.Signer
 }
 
-// New returns a builtinSigner given key and cert chain
+// New returns a [notation.Signer] given key and cert chain.
+//
+// Deprecated: New function exists for historical compatibility and
+// should not be used. To create [GenericSigner],
+// use NewGenericSigner() function.
 func New(key crypto.PrivateKey, certChain []*x509.Certificate) (notation.Signer, error) {
+	return NewGenericSigner(key, certChain)
+}
+
+// NewGenericSigner returns a builtinSigner given key and cert chain.
+func NewGenericSigner(key crypto.PrivateKey, certChain []*x509.Certificate) (*GenericSigner, error) {
 	localSigner, err := signature.NewLocalSigner(certChain, key)
 	if err != nil {
 		return nil, err
 	}
-	return &genericSigner{
-		Signer: localSigner,
+	return &GenericSigner{
+		signer: localSigner,
 	}, nil
 }
 
-// NewFromFiles returns a builtinSigner given key and certChain paths.
+// NewFromFiles returns a [notation.Signer] given key and certChain paths.
 func NewFromFiles(keyPath, certChainPath string) (notation.Signer, error) {
+	return NewGenericSignerFromFiles(keyPath, certChainPath)
+}
+
+// NewGenericSignerFromFiles returns a builtinSigner given key and certChain
+// paths.
+func NewGenericSignerFromFiles(keyPath, certChainPath string) (*GenericSigner, error) {
 	if keyPath == "" {
 		return nil, errors.New("key path not specified")
 	}
@@ -67,12 +96,12 @@ func NewFromFiles(keyPath, certChainPath string) (notation.Signer, error) {
 	}
 
 	// create signer
-	return New(cert.PrivateKey, certs)
+	return NewGenericSigner(cert.PrivateKey, certs)
 }
 
 // Sign signs the artifact described by its descriptor and returns the
-// marshalled envelope.
-func (s *genericSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+// signature and SignerInfo.
+func (s *GenericSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
 	logger := log.GetLogger(ctx)
 	logger.Debugf("Generic signing for %v in signature media type %v", desc.Digest, opts.SignatureMediaType)
 	// Generate payload to be signed.
@@ -81,22 +110,30 @@ func (s *genericSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts
 	if err != nil {
 		return nil, nil, fmt.Errorf("envelope payload can't be marshalled: %w", err)
 	}
-
 	var signingAgentId string
 	if opts.SigningAgent != "" {
 		signingAgentId = opts.SigningAgent
 	} else {
 		signingAgentId = signingAgent
 	}
+	if opts.Timestamper != nil && opts.TSARootCAs == nil {
+		return nil, nil, errors.New("timestamping: got Timestamper but nil TSARootCAs")
+	}
+	if opts.TSARootCAs != nil && opts.Timestamper == nil {
+		return nil, nil, errors.New("timestamping: got TSARootCAs but nil Timestamper")
+	}
 	signReq := &signature.SignRequest{
 		Payload: signature.Payload{
 			ContentType: envelope.MediaTypePayloadV1,
 			Content:     payloadBytes,
 		},
-		Signer:        s.Signer,
-		SigningTime:   time.Now(),
-		SigningScheme: signature.SigningSchemeX509,
-		SigningAgent:  signingAgentId,
+		Signer:                 s.signer,
+		SigningTime:            time.Now(),
+		SigningScheme:          signature.SigningSchemeX509,
+		SigningAgent:           signingAgentId,
+		Timestamper:            opts.Timestamper,
+		TSARootCAs:             opts.TSARootCAs,
+		TSARevocationValidator: opts.TSARevocationValidator,
 	}
 
 	// Add expiry only if ExpiryDuration is not zero
@@ -110,18 +147,25 @@ func (s *genericSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts
 	logger.Debugf("  Expiry:        %v", signReq.Expiry)
 	logger.Debugf("  SigningScheme: %v", signReq.SigningScheme)
 	logger.Debugf("  SigningAgent:  %v", signReq.SigningAgent)
+	if signReq.Timestamper != nil {
+		logger.Debug("Enabled timestamping")
+		if signReq.TSARevocationValidator != nil {
+			logger.Debug("Enabled timestamping certificate chain revocation check")
+		}
+	}
+
+	// Add ctx to the SignRequest
+	signReq = signReq.WithContext(ctx)
 
 	// perform signing
 	sigEnv, err := signature.NewEnvelope(opts.SignatureMediaType)
 	if err != nil {
 		return nil, nil, err
 	}
-
 	sig, err := sigEnv.Sign(signReq)
 	if err != nil {
 		return nil, nil, err
 	}
-
 	envContent, err := sigEnv.Verify()
 	if err != nil {
 		return nil, nil, fmt.Errorf("generated signature failed verification: %v", err)
@@ -129,7 +173,29 @@ func (s *genericSigner) Sign(ctx context.Context, desc ocispec.Descriptor, opts
 	if err := envelope.ValidatePayloadContentType(&envContent.Payload); err != nil {
 		return nil, nil, err
 	}
-
-	// TODO: re-enable timestamping https://github.com/notaryproject/notation-go/issues/78
 	return sig, &envContent.SignerInfo, nil
 }
+
+// SignBlob signs the descriptor returned by genDesc, and returns the
+// signature and SignerInfo.
+func (s *GenericSigner) SignBlob(ctx context.Context, genDesc notation.BlobDescriptorGenerator, opts notation.SignerSignOptions) ([]byte, *signature.SignerInfo, error) {
+	logger := log.GetLogger(ctx)
+	logger.Debugf("Generic blob signing for signature media type %s", opts.SignatureMediaType)
+	ks, err := s.signer.KeySpec()
+	if err != nil {
+		return nil, nil, err
+	}
+	desc, err := getDescriptor(ks, genDesc)
+	if err != nil {
+		return nil, nil, err
+	}
+	return s.Sign(ctx, desc, opts)
+}
+
+func getDescriptor(ks signature.KeySpec, genDesc notation.BlobDescriptorGenerator) (ocispec.Descriptor, error) {
+	digestAlg, ok := algorithms[ks.SignatureAlgorithm().Hash()]
+	if !ok {
+		return ocispec.Descriptor{}, fmt.Errorf("unknown hashing algo %v", ks.SignatureAlgorithm().Hash())
+	}
+	return genDesc(digestAlg)
+}

signer/signer_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package signer
 
 import (
@@ -17,17 +30,23 @@ import (
 	"testing"
 	"time"
 
+	"github.com/notaryproject/notation-core-go/revocation"
+	"github.com/notaryproject/notation-core-go/revocation/purpose"
 	"github.com/notaryproject/notation-core-go/signature"
 	_ "github.com/notaryproject/notation-core-go/signature/cose"
 	_ "github.com/notaryproject/notation-core-go/signature/jws"
 	"github.com/notaryproject/notation-core-go/testhelper"
+	nx509 "github.com/notaryproject/notation-core-go/x509"
 	"github.com/notaryproject/notation-go"
 	"github.com/notaryproject/notation-go/internal/envelope"
 	"github.com/notaryproject/notation-go/plugin/proto"
+	"github.com/notaryproject/tspclient-go"
 	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
+const rfc3161URL = "http://timestamp.digicert.com"
+
 type keyCertPair struct {
 	keySpecName string
 	key         crypto.PrivateKey
@@ -36,7 +55,8 @@ type keyCertPair struct {
 
 var keyCertPairCollections []*keyCertPair
 
-// setUpKeyCertPairCollections setups all combinations of private key and certificates.
+// setUpKeyCertPairCollections setups all combinations of private key and
+// certificates.
 func setUpKeyCertPairCollections() []*keyCertPair {
 	// rsa
 	var keyCertPairs []*keyCertPair
@@ -104,7 +124,7 @@ func generateKeyBytes(key crypto.PrivateKey) (keyBytes []byte, err error) {
 	return keyBytes, nil
 }
 
-func prepareTestKeyCertFile(keyCert *keyCertPair, envelopeType, dir string) (string, string, error) {
+func prepareTestKeyCertFile(keyCert *keyCertPair, dir string) (string, string, error) {
 	keyPath, certPath := filepath.Join(dir, keyCert.keySpecName+".key"), filepath.Join(dir, keyCert.keySpecName+".cert")
 	keyBytes, err := generateKeyBytes(keyCert.key)
 	if err != nil {
@@ -125,7 +145,7 @@ func prepareTestKeyCertFile(keyCert *keyCertPair, envelopeType, dir string) (str
 }
 
 func testSignerFromFile(t *testing.T, keyCert *keyCertPair, envelopeType, dir string) {
-	keyPath, certPath, err := prepareTestKeyCertFile(keyCert, envelopeType, dir)
+	keyPath, certPath, err := prepareTestKeyCertFile(keyCert, dir)
 	if err != nil {
 		t.Fatalf("prepareTestKeyCertFile() failed: %v", err)
 	}
@@ -143,6 +163,17 @@ func testSignerFromFile(t *testing.T, keyCert *keyCertPair, envelopeType, dir st
 	basicVerification(t, sig, envelopeType, keyCert.certs[len(keyCert.certs)-1], nil)
 }
 
+func TestGenericSignerImpl(t *testing.T) {
+	g := &GenericSigner{}
+	if _, ok := interface{}(g).(notation.Signer); !ok {
+		t.Fatal("GenericSigner does not implement notation.Signer")
+	}
+
+	if _, ok := interface{}(g).(notation.BlobSigner); !ok {
+		t.Fatal("GenericSigner does not implement notation.BlobSigner")
+	}
+}
+
 func TestNewFromFiles(t *testing.T) {
 	// sign with key
 	dir := t.TempDir()
@@ -155,12 +186,134 @@ func TestNewFromFiles(t *testing.T) {
 	}
 }
 
+func TestNewFromFilesError(t *testing.T) {
+	tests := map[string]struct {
+		keyPath  string
+		certPath string
+		errMsg   string
+	}{
+		"empty key path": {
+			keyPath:  "",
+			certPath: "someCert",
+			errMsg:   "key path not specified",
+		},
+		"empty cert path": {
+			keyPath:  "someKeyId",
+			certPath: "",
+			errMsg:   "certificate path not specified",
+		},
+	}
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			_, err := NewFromFiles(tc.keyPath, tc.certPath)
+			if err == nil || err.Error() != tc.errMsg {
+				t.Fatalf("TestNewFromPluginFailed expects error %q, got %q", tc.errMsg, err.Error())
+			}
+		})
+	}
+}
+
+func TestNewError(t *testing.T) {
+	wantErr := "\"certs\" param is invalid. Error: empty certs"
+	_, err := New(nil, nil)
+	if err == nil || err.Error() != wantErr {
+		t.Fatalf("TestNewFromPluginFailed expects error %q, got %q", wantErr, err.Error())
+	}
+}
+
 func TestSignWithCertChain(t *testing.T) {
 	// sign with key
 	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
 		for _, keyCert := range keyCertPairCollections {
 			t.Run(fmt.Sprintf("envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
-				validateSignWithCerts(t, envelopeType, keyCert.key, keyCert.certs)
+				validateSignWithCerts(t, envelopeType, keyCert.key, keyCert.certs, false)
+			})
+		}
+	}
+}
+
+func TestSignWithTimestamping(t *testing.T) {
+	// sign with key
+	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
+		for _, keyCert := range keyCertPairCollections {
+			t.Run(fmt.Sprintf("envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
+				validateSignWithCerts(t, envelopeType, keyCert.key, keyCert.certs, true)
+			})
+		}
+	}
+
+	// timestamping without timestamper
+	envelopeType := signature.RegisteredEnvelopeTypes()[0]
+	keyCert := keyCertPairCollections[0]
+	s, err := New(keyCert.key, keyCert.certs)
+	if err != nil {
+		t.Fatalf("NewSigner() error = %v", err)
+	}
+	ctx := context.Background()
+	desc, sOpts := generateSigningContent()
+	sOpts.SignatureMediaType = envelopeType
+	sOpts.TSARootCAs = x509.NewCertPool()
+	_, _, err = s.Sign(ctx, desc, sOpts)
+	expectedErrMsg := "timestamping: got TSARootCAs but nil Timestamper"
+	if err == nil || err.Error() != expectedErrMsg {
+		t.Fatalf("expected %s, but got %s", expectedErrMsg, err)
+	}
+
+	// timestamping without TSARootCAs
+	desc, sOpts = generateSigningContent()
+	sOpts.SignatureMediaType = envelopeType
+	sOpts.Timestamper, err = tspclient.NewHTTPTimestamper(nil, rfc3161URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, _, err = s.Sign(ctx, desc, sOpts)
+	expectedErrMsg = "timestamping: got Timestamper but nil TSARootCAs"
+	if err == nil || err.Error() != expectedErrMsg {
+		t.Fatalf("expected %s, but got %s", expectedErrMsg, err)
+	}
+
+	// timestamping with unknown authority
+	desc, sOpts = generateSigningContent()
+	sOpts.SignatureMediaType = envelopeType
+	sOpts.Timestamper, err = tspclient.NewHTTPTimestamper(nil, rfc3161URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	sOpts.TSARootCAs = x509.NewCertPool()
+	tsaRevocationValidator, err := revocation.NewWithOptions(revocation.Options{
+		CertChainPurpose: purpose.Timestamping,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	sOpts.TSARevocationValidator = tsaRevocationValidator
+	_, _, err = s.Sign(ctx, desc, sOpts)
+	expectedErrMsg = "timestamp: failed to verify signed token: cms verification failure: x509: certificate signed by unknown authority"
+	if err == nil || err.Error() != expectedErrMsg {
+		t.Fatalf("expected %s, but got %s", expectedErrMsg, err)
+	}
+}
+
+func TestSignBlobWithCertChain(t *testing.T) {
+	// sign with key
+	for _, envelopeType := range signature.RegisteredEnvelopeTypes() {
+		for _, keyCert := range keyCertPairCollections {
+			t.Run(fmt.Sprintf("envelopeType=%v_keySpec=%v", envelopeType, keyCert.keySpecName), func(t *testing.T) {
+				s, err := NewGenericSigner(keyCert.key, keyCert.certs)
+				if err != nil {
+					t.Fatalf("NewSigner() error = %v", err)
+				}
+
+				sOpts := notation.SignerSignOptions{
+					SignatureMediaType: envelopeType,
+				}
+				sig, _, err := s.SignBlob(context.Background(), getDescriptorFunc(false), sOpts)
+				if err != nil {
+					t.Fatalf("Sign() error = %v", err)
+				}
+
+				// basic verification
+				basicVerification(t, sig, envelopeType, keyCert.certs[len(keyCert.certs)-1], nil)
 			})
 		}
 	}
@@ -196,7 +349,7 @@ func signRSA(digest []byte, hash crypto.Hash, pk *rsa.PrivateKey) ([]byte, error
 	return rsa.SignPSS(rand.Reader, pk, hash, digest, &rsa.PSSOptions{SaltLength: rsa.PSSSaltLengthEqualsHash})
 }
 
-func signECDSA(digest []byte, hash crypto.Hash, pk *ecdsa.PrivateKey) ([]byte, error) {
+func signECDSA(digest []byte, pk *ecdsa.PrivateKey) ([]byte, error) {
 	r, s, err := ecdsa.Sign(rand.Reader, pk, digest)
 	if err != nil {
 		return nil, err
@@ -216,7 +369,7 @@ func localSign(payload []byte, hash crypto.Hash, pk crypto.PrivateKey) ([]byte,
 	case *rsa.PrivateKey:
 		return signRSA(digest, hash, key)
 	case *ecdsa.PrivateKey:
-		return signECDSA(digest, hash, key)
+		return signECDSA(digest, key)
 	default:
 		return nil, errors.New("signing private key not supported")
 	}
@@ -281,7 +434,7 @@ func verifySigningAgent(t *testing.T, signingAgentId string, metadata *proto.Get
 	}
 }
 
-func validateSignWithCerts(t *testing.T, envelopeType string, key crypto.PrivateKey, certs []*x509.Certificate) {
+func validateSignWithCerts(t *testing.T, envelopeType string, key crypto.PrivateKey, certs []*x509.Certificate, timestamp bool) {
 	s, err := New(key, certs)
 	if err != nil {
 		t.Fatalf("NewSigner() error = %v", err)
@@ -290,6 +443,19 @@ func validateSignWithCerts(t *testing.T, envelopeType string, key crypto.Private
 	ctx := context.Background()
 	desc, sOpts := generateSigningContent()
 	sOpts.SignatureMediaType = envelopeType
+	if timestamp {
+		sOpts.Timestamper, err = tspclient.NewHTTPTimestamper(nil, rfc3161URL)
+		if err != nil {
+			t.Fatal(err)
+		}
+		rootCerts, err := nx509.ReadCertificateFile("./testdata/DigiCertTSARootSHA384.cer")
+		if err != nil {
+			t.Fatal(err)
+		}
+		rootCAs := x509.NewCertPool()
+		rootCAs.AddCert(rootCerts[0])
+		sOpts.TSARootCAs = rootCAs
+	}
 	sig, _, err := s.Sign(ctx, desc, sOpts)
 	if err != nil {
 		t.Fatalf("Sign() error = %v", err)

verifier/crl/crl.go

@@ -0,0 +1,171 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package crl provides functionalities for crl revocation check.
+package crl
+
+import (
+	"context"
+	"crypto/sha256"
+	"crypto/x509"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"time"
+
+	corecrl "github.com/notaryproject/notation-core-go/revocation/crl"
+	"github.com/notaryproject/notation-go/internal/file"
+	"github.com/notaryproject/notation-go/log"
+)
+
+// FileCache implements corecrl.Cache.
+//
+// Key: url of the CRL.
+//
+// Value: corecrl.Bundle.
+//
+// This cache builds on top of the UNIX file system to leverage the file system's
+// atomic operations. The `rename` and `remove` operations will unlink the old
+// file but keep the inode and file descriptor for existing processes to access
+// the file. The old inode will be dereferenced when all processes close the old
+// file descriptor. Additionally, the operations are proven to be atomic on
+// UNIX-like platforms, so there is no need to handle file locking.
+//
+// NOTE: For Windows, the `open`, `rename` and `remove` operations need file
+// locking to ensure atomicity. The current implementation does not handle
+// file locking, so the concurrent write from multiple processes may be failed.
+// Please do not use this cache in a multi-process environment on Windows.
+type FileCache struct {
+	// root is the root directory of the cache
+	root string
+}
+
+// fileCacheContent is the actual content saved in a FileCache
+type fileCacheContent struct {
+	// BaseCRL is the ASN.1 encoded base CRL
+	BaseCRL []byte `json:"baseCRL"`
+
+	// DeltaCRL is the ASN.1 encoded delta CRL
+	DeltaCRL []byte `json:"deltaCRL,omitempty"`
+}
+
+// NewFileCache creates a FileCache with root as the root directory
+//
+// An example for root is `dir.CacheFS().SysPath(dir.PathCRLCache)`
+func NewFileCache(root string) (*FileCache, error) {
+	if err := os.MkdirAll(root, 0700); err != nil {
+		return nil, fmt.Errorf("failed to create crl file cache: %w", err)
+	}
+	return &FileCache{
+		root: root,
+	}, nil
+}
+
+// Get retrieves CRL bundle from c given url as key. If the key does not exist
+// or the content has expired, corecrl.ErrCacheMiss is returned.
+func (c *FileCache) Get(ctx context.Context, url string) (*corecrl.Bundle, error) {
+	logger := log.GetLogger(ctx)
+	logger.Debugf("Retrieving crl bundle from file cache with key %q ...", url)
+
+	// get content from file cache
+	contentBytes, err := os.ReadFile(filepath.Join(c.root, c.fileName(url)))
+	if err != nil {
+		if errors.Is(err, fs.ErrNotExist) {
+			logger.Debugf("CRL file cache miss. Key %q does not exist", url)
+			return nil, corecrl.ErrCacheMiss
+		}
+		return nil, fmt.Errorf("failed to get crl bundle from file cache with key %q: %w", url, err)
+	}
+
+	// decode content to crl Bundle
+	var content fileCacheContent
+	if err := json.Unmarshal(contentBytes, &content); err != nil {
+		return nil, fmt.Errorf("failed to decode file retrieved from file cache: %w", err)
+	}
+	var bundle corecrl.Bundle
+	bundle.BaseCRL, err = x509.ParseRevocationList(content.BaseCRL)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse base CRL of file retrieved from file cache: %w", err)
+	}
+	if content.DeltaCRL != nil {
+		bundle.DeltaCRL, err = x509.ParseRevocationList(content.DeltaCRL)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse delta CRL of file retrieved from file cache: %w", err)
+		}
+	}
+
+	// check expiry
+	if err := checkExpiry(ctx, bundle.BaseCRL.NextUpdate); err != nil {
+		return nil, fmt.Errorf("check BaseCRL expiry failed: %w", err)
+	}
+	if bundle.DeltaCRL != nil {
+		if err := checkExpiry(ctx, bundle.DeltaCRL.NextUpdate); err != nil {
+			return nil, fmt.Errorf("check DeltaCRL expiry failed: %w", err)
+		}
+	}
+
+	return &bundle, nil
+}
+
+// Set stores the CRL bundle in c with url as key.
+func (c *FileCache) Set(ctx context.Context, url string, bundle *corecrl.Bundle) error {
+	logger := log.GetLogger(ctx)
+	logger.Debugf("Storing crl bundle to file cache with key %q ...", url)
+
+	if bundle == nil {
+		return errors.New("failed to store crl bundle in file cache: bundle cannot be nil")
+	}
+	if bundle.BaseCRL == nil {
+		return errors.New("failed to store crl bundle in file cache: bundle BaseCRL cannot be nil")
+	}
+
+	// actual content to be saved in the cache
+	content := fileCacheContent{
+		BaseCRL: bundle.BaseCRL.Raw,
+	}
+	if bundle.DeltaCRL != nil {
+		content.DeltaCRL = bundle.DeltaCRL.Raw
+	}
+	contentBytes, err := json.Marshal(content)
+	if err != nil {
+		return fmt.Errorf("failed to store crl bundle in file cache: %w", err)
+	}
+	if err := file.WriteFile(c.root, filepath.Join(c.root, c.fileName(url)), contentBytes); err != nil {
+		return fmt.Errorf("failed to store crl bundle in file cache: %w", err)
+	}
+	return nil
+}
+
+// fileName returns the filename of the content stored in c
+func (c *FileCache) fileName(url string) string {
+	hash := sha256.Sum256([]byte(url))
+	return hex.EncodeToString(hash[:])
+}
+
+// checkExpiry returns nil when nextUpdate is bounded before current time
+func checkExpiry(ctx context.Context, nextUpdate time.Time) error {
+	logger := log.GetLogger(ctx)
+
+	if nextUpdate.IsZero() {
+		return errors.New("crl bundle retrieved from file cache does not contain valid NextUpdate")
+	}
+	if time.Now().After(nextUpdate) {
+		logger.Debugf("CRL bundle retrieved from file cache has expired at %s", nextUpdate)
+		return corecrl.ErrCacheMiss
+	}
+	return nil
+}

verifier/crl/crl_test.go

@@ -0,0 +1,395 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package crl
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/x509"
+	"encoding/json"
+	"errors"
+	"math/big"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+
+	corecrl "github.com/notaryproject/notation-core-go/revocation/crl"
+	"github.com/notaryproject/notation-core-go/testhelper"
+)
+
+func TestCache(t *testing.T) {
+	t.Run("file cache implement Cache interface", func(t *testing.T) {
+		root := t.TempDir()
+		var coreCache corecrl.Cache
+		var err error
+		coreCache, err = NewFileCache(root)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if _, ok := coreCache.(*FileCache); !ok {
+			t.Fatal("FileCache does not implement coreCache")
+		}
+	})
+}
+
+func TestFileCache(t *testing.T) {
+	now := time.Now()
+	certChain := testhelper.GetRevokableRSAChainWithRevocations(2, false, true)
+	crlBytes, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+		Number:     big.NewInt(1),
+		NextUpdate: now.Add(time.Hour),
+	}, certChain[1].Cert, certChain[1].PrivateKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	baseCRL, err := x509.ParseRevocationList(crlBytes)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := context.Background()
+	root := t.TempDir()
+	cache, err := NewFileCache(root)
+	t.Run("NewFileCache", func(t *testing.T) {
+		if err != nil {
+			t.Fatalf("expected no error, but got %v", err)
+		}
+		if cache.root != root {
+			t.Fatalf("expected root %v, but got %v", root, cache.root)
+		}
+	})
+
+	key := "http://example.com"
+	t.Run("comformance", func(t *testing.T) {
+		bundle := &corecrl.Bundle{BaseCRL: baseCRL}
+		if err := cache.Set(ctx, key, bundle); err != nil {
+			t.Fatal(err)
+		}
+		retrievedBundle, err := cache.Get(ctx, key)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if !reflect.DeepEqual(retrievedBundle.BaseCRL, bundle.BaseCRL) {
+			t.Fatalf("expected BaseCRL %+v, but got %+v", bundle.BaseCRL, retrievedBundle.BaseCRL)
+		}
+
+		if bundle.DeltaCRL != nil {
+			t.Fatalf("expected DeltaCRL to be nil, but got %+v", retrievedBundle.DeltaCRL)
+		}
+	})
+
+	t.Run("comformance with delta crl", func(t *testing.T) {
+		crlBytes, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+			Number:     big.NewInt(2),
+			NextUpdate: now.Add(time.Hour),
+		}, certChain[1].Cert, certChain[1].PrivateKey)
+		if err != nil {
+			t.Fatal(err)
+		}
+		deltaCRL, err := x509.ParseRevocationList(crlBytes)
+		if err != nil {
+			t.Fatal(err)
+		}
+		bundle := &corecrl.Bundle{BaseCRL: baseCRL, DeltaCRL: deltaCRL}
+		if err := cache.Set(ctx, key, bundle); err != nil {
+			t.Fatal(err)
+		}
+		retrievedBundle, err := cache.Get(ctx, key)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if !reflect.DeepEqual(retrievedBundle.BaseCRL, bundle.BaseCRL) {
+			t.Fatalf("expected BaseCRL %+v, but got %+v", bundle.BaseCRL, retrievedBundle.BaseCRL)
+		}
+
+		if !reflect.DeepEqual(retrievedBundle.DeltaCRL, bundle.DeltaCRL) {
+			t.Fatalf("expected DeltaCRL %+v, but got %+v", bundle.DeltaCRL, retrievedBundle.DeltaCRL)
+		}
+	})
+}
+
+func TestNewFileCacheFailed(t *testing.T) {
+	tempDir := t.TempDir()
+	t.Run("without permission to create cache directory", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		if err := os.Chmod(tempDir, 0); err != nil {
+			t.Fatal(err)
+		}
+		root := filepath.Join(tempDir, "test")
+		_, err := NewFileCache(root)
+		if !strings.Contains(err.Error(), "permission denied") {
+			t.Fatalf("expected permission denied error, but got %v", err)
+		}
+		// restore permission
+		if err := os.Chmod(tempDir, 0755); err != nil {
+			t.Fatalf("failed to change permission: %v", err)
+		}
+	})
+}
+
+func TestGetFailed(t *testing.T) {
+	tempDir := t.TempDir()
+	cache, err := NewFileCache(tempDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Run("key does not exist", func(t *testing.T) {
+		_, err := cache.Get(context.Background(), "nonExistKey")
+		if !errors.Is(err, corecrl.ErrCacheMiss) {
+			t.Fatalf("expected ErrCacheMiss, but got %v", err)
+		}
+	})
+
+	invalidFile := filepath.Join(tempDir, cache.fileName("invalid"))
+	if err := os.WriteFile(invalidFile, []byte("invalid"), 0644); err != nil {
+		t.Fatalf("failed to write file: %v", err)
+	}
+
+	t.Run("no permission to read file", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		if err := os.Chmod(invalidFile, 0); err != nil {
+			t.Fatal(err)
+		}
+		_, err := cache.Get(context.Background(), "invalid")
+		if err == nil || !strings.Contains(err.Error(), "permission denied") {
+			t.Fatalf("expected permission denied error, but got %v", err)
+		}
+		// restore permission
+		if err := os.Chmod(invalidFile, 0755); err != nil {
+			t.Fatal(err)
+		}
+	})
+
+	t.Run("invalid content", func(t *testing.T) {
+		_, err := cache.Get(context.Background(), "invalid")
+		expectedErrMsg := "failed to decode file retrieved from file cache: invalid character 'i' looking for beginning of value"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	now := time.Now()
+	certChain := testhelper.GetRevokableRSAChainWithRevocations(2, false, true)
+	crlBytes, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+		Number: big.NewInt(1),
+	}, certChain[1].Cert, certChain[1].PrivateKey)
+	if err != nil {
+		t.Fatalf("failed to create base CRL: %v", err)
+	}
+	baseCRL, err := x509.ParseRevocationList(crlBytes)
+	if err != nil {
+		t.Fatalf("failed to parse base CRL: %v", err)
+	}
+
+	t.Run("empty RawBaseCRL of content", func(t *testing.T) {
+		content := fileCacheContent{
+			BaseCRL: []byte{},
+		}
+		b, err := json.Marshal(content)
+		if err != nil {
+			t.Fatal(err)
+		}
+		invalidBundleFile := filepath.Join(tempDir, cache.fileName("invalidBundle"))
+		if err := os.WriteFile(invalidBundleFile, b, 0644); err != nil {
+			t.Fatalf("failed to write file: %v", err)
+		}
+		_, err = cache.Get(context.Background(), "invalidBundle")
+		expectedErrMsg := "failed to parse base CRL of file retrieved from file cache: x509: malformed crl"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	t.Run("invalid RawBaseCRL of content", func(t *testing.T) {
+		content := fileCacheContent{
+			BaseCRL: []byte("invalid"),
+		}
+		b, err := json.Marshal(content)
+		if err != nil {
+			t.Fatal(err)
+		}
+		invalidBundleFile := filepath.Join(tempDir, cache.fileName("invalidBundle"))
+		if err := os.WriteFile(invalidBundleFile, b, 0644); err != nil {
+			t.Fatalf("failed to write file: %v", err)
+		}
+		_, err = cache.Get(context.Background(), "invalidBundle")
+		expectedErrMsg := "failed to parse base CRL of file retrieved from file cache: x509: malformed crl"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	t.Run("invalid RawDeltaCRL of content", func(t *testing.T) {
+		content := fileCacheContent{
+			BaseCRL:  baseCRL.Raw,
+			DeltaCRL: []byte("invalid"),
+		}
+		b, err := json.Marshal(content)
+		if err != nil {
+			t.Fatal(err)
+		}
+		invalidBundleFile := filepath.Join(tempDir, cache.fileName("invalidBundle"))
+		if err := os.WriteFile(invalidBundleFile, b, 0644); err != nil {
+			t.Fatalf("failed to write file: %v", err)
+		}
+		_, err = cache.Get(context.Background(), "invalidBundle")
+		expectedErrMsg := "failed to parse delta CRL of file retrieved from file cache: x509: malformed crl"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	t.Run("bundle with invalid NextUpdate", func(t *testing.T) {
+		ctx := context.Background()
+		expiredBundle := &corecrl.Bundle{BaseCRL: baseCRL}
+		if err := cache.Set(ctx, "expiredKey", expiredBundle); err != nil {
+			t.Fatal(err)
+		}
+		_, err = cache.Get(ctx, "expiredKey")
+		expectedErrMsg := "check BaseCRL expiry failed: crl bundle retrieved from file cache does not contain valid NextUpdate"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	crlBytes, err = x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+		Number:     big.NewInt(1),
+		NextUpdate: now.Add(-time.Hour),
+	}, certChain[1].Cert, certChain[1].PrivateKey)
+	if err != nil {
+		t.Fatalf("failed to create base CRL: %v", err)
+	}
+	expiredBaseCRL, err := x509.ParseRevocationList(crlBytes)
+	if err != nil {
+		t.Fatalf("failed to parse base CRL: %v", err)
+	}
+	t.Run("base crl in cache has expired", func(t *testing.T) {
+		ctx := context.Background()
+		expiredBundle := &corecrl.Bundle{BaseCRL: expiredBaseCRL}
+		if err := cache.Set(ctx, "expiredKey", expiredBundle); err != nil {
+			t.Fatal(err)
+		}
+		_, err = cache.Get(ctx, "expiredKey")
+		if !errors.Is(err, corecrl.ErrCacheMiss) {
+			t.Fatalf("expected ErrCacheMiss, but got %v", err)
+		}
+	})
+
+	t.Run("delta crl in cache has expired", func(t *testing.T) {
+		ctx := context.Background()
+		crlBytes, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+			Number:     big.NewInt(1),
+			NextUpdate: now.Add(time.Hour),
+		}, certChain[1].Cert, certChain[1].PrivateKey)
+		if err != nil {
+			t.Fatalf("failed to create base CRL: %v", err)
+		}
+		baseCRL, err := x509.ParseRevocationList(crlBytes)
+		if err != nil {
+			t.Fatalf("failed to parse base CRL: %v", err)
+		}
+		crlBytes, err = x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+			Number:     big.NewInt(1),
+			NextUpdate: now.Add(-time.Hour),
+		}, certChain[1].Cert, certChain[1].PrivateKey)
+		if err != nil {
+			t.Fatalf("failed to create base CRL: %v", err)
+		}
+		expiredDeltaCRL, err := x509.ParseRevocationList(crlBytes)
+		if err != nil {
+			t.Fatalf("failed to parse base CRL: %v", err)
+		}
+		expiredBundle := &corecrl.Bundle{BaseCRL: baseCRL, DeltaCRL: expiredDeltaCRL}
+		if err := cache.Set(ctx, "expiredKey", expiredBundle); err != nil {
+			t.Fatal(err)
+		}
+		_, err = cache.Get(ctx, "expiredKey")
+		if !errors.Is(err, corecrl.ErrCacheMiss) {
+			t.Fatalf("expected ErrCacheMiss, but got %v", err)
+		}
+	})
+}
+
+func TestSetFailed(t *testing.T) {
+	tempDir := t.TempDir()
+	cache, err := NewFileCache(tempDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	now := time.Now()
+	certChain := testhelper.GetRevokableRSAChainWithRevocations(2, false, true)
+	crlBytes, err := x509.CreateRevocationList(rand.Reader, &x509.RevocationList{
+		Number:     big.NewInt(1),
+		NextUpdate: now.Add(time.Hour),
+	}, certChain[1].Cert, certChain[1].PrivateKey)
+	if err != nil {
+		t.Fatal(err)
+	}
+	baseCRL, err := x509.ParseRevocationList(crlBytes)
+	if err != nil {
+		t.Fatal(err)
+	}
+	ctx := context.Background()
+	key := "testKey"
+
+	t.Run("nil bundle", func(t *testing.T) {
+		err := cache.Set(ctx, key, nil)
+		expectedErrMsg := "failed to store crl bundle in file cache: bundle cannot be nil"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	t.Run("nil bundle BaseCRL", func(t *testing.T) {
+		bundle := &corecrl.Bundle{}
+		err := cache.Set(ctx, key, bundle)
+		expectedErrMsg := "failed to store crl bundle in file cache: bundle BaseCRL cannot be nil"
+		if err == nil || err.Error() != expectedErrMsg {
+			t.Fatalf("expected %s, but got %v", expectedErrMsg, err)
+		}
+	})
+
+	t.Run("failed to write into cache due to permission denied", func(t *testing.T) {
+		if runtime.GOOS == "windows" {
+			t.Skip("skipping test on Windows")
+		}
+
+		if err := os.Chmod(tempDir, 0); err != nil {
+			t.Fatal(err)
+		}
+		bundle := &corecrl.Bundle{BaseCRL: baseCRL}
+		err := cache.Set(ctx, key, bundle)
+		if err == nil || !strings.Contains(err.Error(), "permission denied") {
+			t.Fatalf("expected permission denied error, but got %v", err)
+		}
+		// restore permission
+		if err := os.Chmod(tempDir, 0755); err != nil {
+			t.Fatalf("failed to change permission: %v", err)
+		}
+	})
+}

verifier/helpers.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package verifier
 
 import (
@@ -5,12 +18,12 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
-	"regexp"
 	"strings"
 
 	"github.com/notaryproject/notation-core-go/signature"
 	"github.com/notaryproject/notation-go"
 	set "github.com/notaryproject/notation-go/internal/container"
+	notationsemver "github.com/notaryproject/notation-go/internal/semver"
 	"github.com/notaryproject/notation-go/internal/slices"
 	"github.com/notaryproject/notation-go/verifier/trustpolicy"
 	"github.com/notaryproject/notation-go/verifier/truststore"
@@ -34,10 +47,7 @@ var VerificationPluginHeaders = []string{
 
 var errExtendedAttributeNotExist = errors.New("extended attribute not exist")
 
-// semVerRegEx is takenfrom https://semver.org/#is-there-a-suggested-regular-expression-regex-to-check-a-semver-string
-var semVerRegEx = regexp.MustCompile(`^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$`)
-
-func loadX509TrustStores(ctx context.Context, scheme signature.SigningScheme, policy *trustpolicy.TrustPolicy, x509TrustStore truststore.X509TrustStore) ([]*x509.Certificate, error) {
+func loadX509TrustStores(ctx context.Context, scheme signature.SigningScheme, policyName string, trustStores []string, x509TrustStore truststore.X509TrustStore) ([]*x509.Certificate, error) {
 	var typeToLoad truststore.Type
 	switch scheme {
 	case signature.SigningSchemeX509:
@@ -45,39 +55,15 @@ func loadX509TrustStores(ctx context.Context, scheme signature.SigningScheme, po
 	case signature.SigningSchemeX509SigningAuthority:
 		typeToLoad = truststore.TypeSigningAuthority
 	default:
-		return nil, fmt.Errorf("unrecognized signing scheme %q", scheme)
+		return nil, truststore.TrustStoreError{Msg: fmt.Sprintf("error while loading the trust store, unrecognized signing scheme %q", scheme)}
 	}
-
-	processedStoreSet := set.New[string]()
-	var certificates []*x509.Certificate
-	for _, trustStore := range policy.TrustStores {
-		if processedStoreSet.Contains(trustStore) {
-			// we loaded this trust store already
-			continue
-		}
-
-		storeType, name, found := strings.Cut(trustStore, ":")
-		if !found {
-			return nil, fmt.Errorf("trust policy statement %q is missing separator in trust store value %q. The required format is <TrustStoreType>:<TrustStoreName>", policy.Name, trustStore)
-		}
-		if typeToLoad != truststore.Type(storeType) {
-			continue
-		}
-
-		certs, err := x509TrustStore.GetCertificates(ctx, typeToLoad, name)
-		if err != nil {
-			return nil, err
-		}
-		certificates = append(certificates, certs...)
-		processedStoreSet.Add(trustStore)
-	}
-	return certificates, nil
+	return loadX509TrustStoresWithType(ctx, typeToLoad, policyName, trustStores, x509TrustStore)
 }
 
-// isCriticalFailure checks whether a VerificationResult fails the entire
-// signature verification workflow.
+// isCriticalFailure checks whether a [notation.ValidationResult] fails the
+// entire signature verification workflow.
 // signature verification workflow is considered failed if there is a
-// VerificationResult with "Enforced" as the action but the result was
+// ValidationResult with "Enforced" as the action but the result was
 // unsuccessful.
 func isCriticalFailure(result *notation.ValidationResult) bool {
 	return result.Action == trustpolicy.ActionEnforce && result.Error != nil
@@ -139,12 +125,61 @@ func getVerificationPluginMinVersion(signerInfo *signature.SignerInfo) (string,
 	if strings.TrimSpace(version) == "" {
 		return "", fmt.Errorf("%v from extended attribute is an empty string", HeaderVerificationPluginMinVersion)
 	}
-	if !isVersionSemverValid(version) {
+	if !notationsemver.IsValid(version) {
 		return "", fmt.Errorf("%v from extended attribute is not a valid SemVer", HeaderVerificationPluginMinVersion)
 	}
 	return version, nil
 }
 
-func isVersionSemverValid(version string) bool {
-	return semVerRegEx.MatchString(version)
+func loadX509TSATrustStores(ctx context.Context, scheme signature.SigningScheme, policyName string, trustStores []string, x509TrustStore truststore.X509TrustStore) ([]*x509.Certificate, error) {
+	var typeToLoad truststore.Type
+	switch scheme {
+	case signature.SigningSchemeX509:
+		typeToLoad = truststore.TypeTSA
+	default:
+		return nil, truststore.TrustStoreError{Msg: fmt.Sprintf("error while loading the TSA trust store, signing scheme must be notary.x509, but got %s", scheme)}
+	}
+	return loadX509TrustStoresWithType(ctx, typeToLoad, policyName, trustStores, x509TrustStore)
+}
+
+func loadX509TrustStoresWithType(ctx context.Context, trustStoreType truststore.Type, policyName string, trustStores []string, x509TrustStore truststore.X509TrustStore) ([]*x509.Certificate, error) {
+	processedStoreSet := set.New[string]()
+	var certificates []*x509.Certificate
+	for _, trustStore := range trustStores {
+		if processedStoreSet.Contains(trustStore) {
+			// we loaded this trust store already
+			continue
+		}
+
+		storeType, name, found := strings.Cut(trustStore, ":")
+		if !found {
+			return nil, truststore.TrustStoreError{Msg: fmt.Sprintf("error while loading the trust store, trust policy statement %q is missing separator in trust store value %q. The required format is <TrustStoreType>:<TrustStoreName>", policyName, trustStore)}
+		}
+		if trustStoreType != truststore.Type(storeType) {
+			continue
+		}
+
+		certs, err := x509TrustStore.GetCertificates(ctx, trustStoreType, name)
+		if err != nil {
+			return nil, err
+		}
+		certificates = append(certificates, certs...)
+		processedStoreSet.Add(trustStore)
+	}
+	return certificates, nil
+}
+
+// isTSATrustStoreInPolicy checks if tsa trust store is configured in
+// trust policy
+func isTSATrustStoreInPolicy(policyName string, trustStores []string) (bool, error) {
+	for _, trustStore := range trustStores {
+		storeType, _, found := strings.Cut(trustStore, ":")
+		if !found {
+			return false, truststore.TrustStoreError{Msg: fmt.Sprintf("invalid trust policy statement: %q is missing separator in trust store value %q. The required format is <TrustStoreType>:<TrustStoreName>", policyName, trustStore)}
+		}
+		if truststore.Type(storeType) == truststore.TypeTSA {
+			return true, nil
+		}
+	}
+	return false, nil
 }

verifier/helpers_test.go

@@ -1,3 +1,16 @@
+// Copyright The Notary Project Authors.
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package verifier
 
 import (
@@ -15,25 +28,6 @@ import (
 	"github.com/notaryproject/notation-go/verifier/truststore"
 )
 
-func dummyPolicyStatement() (policyStatement trustpolicy.TrustPolicy) {
-	policyStatement = trustpolicy.TrustPolicy{
-		Name:                  "test-statement-name",
-		RegistryScopes:        []string{"registry.acme-rockets.io/software/net-monitor"},
-		SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: "strict"},
-		TrustStores:           []string{"ca:valid-trust-store", "signingAuthority:valid-trust-store"},
-		TrustedIdentities:     []string{"x509.subject:CN=Notation Test Root,O=Notary,L=Seattle,ST=WA,C=US"},
-	}
-	return
-}
-
-func dummyPolicyDocument() (policyDoc trustpolicy.Document) {
-	policyDoc = trustpolicy.Document{
-		Version:       "1.0",
-		TrustPolicies: []trustpolicy.TrustPolicy{dummyPolicyStatement()},
-	}
-	return
-}
-
 func TestGetArtifactDigestFromUri(t *testing.T) {
 
 	tests := []struct {
@@ -66,21 +60,18 @@ func TestLoadX509TrustStore(t *testing.T) {
 	// load "ca" and "signingAuthority" trust store
 	caStore := "ca:valid-trust-store"
 	signingAuthorityStore := "signingAuthority:valid-trust-store"
-	dummyPolicy := dummyPolicyStatement()
+	dummyPolicy := dummyOCIPolicyDocument().TrustPolicies[0]
 	dummyPolicy.TrustStores = []string{caStore, signingAuthorityStore}
 	dir.UserConfigDir = "testdata"
 	x509truststore := truststore.NewX509TrustStore(dir.ConfigFS())
-	caCerts, err := loadX509TrustStores(context.Background(), signature.SigningSchemeX509, &dummyPolicy, x509truststore)
+	_, err := loadX509TrustStores(context.Background(), signature.SigningSchemeX509, dummyPolicy.Name, dummyPolicy.TrustStores, x509truststore)
 	if err != nil {
 		t.Fatalf("TestLoadX509TrustStore should not throw error for a valid trust store. Error: %v", err)
 	}
-	saCerts, err := loadX509TrustStores(context.Background(), signature.SigningSchemeX509SigningAuthority, &dummyPolicy, x509truststore)
+	_, err = loadX509TrustStores(context.Background(), signature.SigningSchemeX509SigningAuthority, dummyPolicy.Name, dummyPolicy.TrustStores, x509truststore)
 	if err != nil {
 		t.Fatalf("TestLoadX509TrustStore should not throw error for a valid trust store. Error: %v", err)
 	}
-	if len(caCerts) != 4 || len(saCerts) != 3 {
-		t.Fatalf("ca store should have 4 certs and signingAuthority store should have 3 certs")
-	}
 }
 
 func TestIsCriticalFailure(t *testing.T) {
@@ -104,6 +95,34 @@ func TestIsCriticalFailure(t *testing.T) {
 	}
 }
 
+func TestLoadX509TSATrustStores(t *testing.T) {
+	policyDoc := trustpolicy.Document{
+		Version: "1.0",
+		TrustPolicies: []trustpolicy.TrustPolicy{
+			{
+				Name:                  "testTSA",
+				RegistryScopes:        []string{"*"},
+				SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: "strict"},
+				TrustStores:           []string{"tsa:test-timestamp"},
+				TrustedIdentities:     []string{"*"},
+			},
+		},
+	}
+	dir.UserConfigDir = "testdata"
+	x509truststore := truststore.NewX509TrustStore(dir.ConfigFS())
+	policyStatement := policyDoc.TrustPolicies[0]
+	_, err := loadX509TSATrustStores(context.Background(), signature.SigningSchemeX509, policyStatement.Name, policyStatement.TrustStores, x509truststore)
+	if err != nil {
+		t.Fatalf("TestLoadX509TrustStore should not throw error for a valid trust store. Error: %v", err)
+	}
+
+	_, err = loadX509TSATrustStores(context.Background(), signature.SigningSchemeX509SigningAuthority, policyStatement.Name, policyStatement.TrustStores, x509truststore)
+	expectedErrMsg := "error while loading the TSA trust store, signing scheme must be notary.x509, but got notary.x509.signingAuthority"
+	if err == nil || err.Error() != expectedErrMsg {
+		t.Fatalf("expected %s, but got %s", expectedErrMsg, err)
+	}
+}
+
 func getArtifactDigestFromReference(artifactReference string) (string, error) {
 	invalidUriErr := fmt.Errorf("artifact URI %q could not be parsed, make sure it is the fully qualified OCI artifact URI without the scheme/protocol. e.g domain.com:80/my/repository@sha256:digest", artifactReference)
 	i := strings.LastIndex(artifactReference, "@")
@@ -118,3 +137,32 @@ func getArtifactDigestFromReference(artifactReference string) (string, error) {
 
 	return artifactReference[i+1:], nil
 }
+
+func dummyOCIPolicyDocument() (policyDoc trustpolicy.OCIDocument) {
+	return trustpolicy.OCIDocument{
+		Version: "1.0",
+		TrustPolicies: []trustpolicy.OCITrustPolicy{
+			{
+				Name:                  "test-statement-name",
+				RegistryScopes:        []string{"registry.acme-rockets.io/software/net-monitor"},
+				SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: "strict"},
+				TrustStores:           []string{"ca:valid-trust-store", "signingAuthority:valid-trust-store"},
+				TrustedIdentities:     []string{"x509.subject:CN=Notation Test Root,O=Notary,L=Seattle,ST=WA,C=US"},
+			},
+		},
+	}
+}
+
+func dummyBlobPolicyDocument() (policyDoc trustpolicy.BlobDocument) {
+	return trustpolicy.BlobDocument{
+		Version: "1.0",
+		TrustPolicies: []trustpolicy.BlobTrustPolicy{
+			{
+				Name:                  "blob-test-statement-name",
+				SignatureVerification: trustpolicy.SignatureVerification{VerificationLevel: "strict"},
+				TrustStores:           []string{"ca:valid-trust-store", "signingAuthority:valid-trust-store"},
+				TrustedIdentities:     []string{"x509.subject:CN=Notation Test Root,O=Notary,L=Seattle,ST=WA,C=US"},
+			},
+		},
+	}
+}