podman-remote: copy secret to contextdir is absolute path on host

Podman remote must treat build secrets as part of context directory. If
secret path is absolute path on host copy it to tar file and pass it to
remote server.

Signed-off-by: Aditya Rajan <arajan@redhat.com>

pkg/api/handlers/compat/images_build.go

@@ -247,7 +247,28 @@ func BuildImage(w http.ResponseWriter, r *http.Request) {
 			utils.BadRequest(w, "secrets", query.Secrets, err)
 			return
 		}
-		secrets = m
+
+		// for podman-remote all secrets must be picked from context director
+		// hence modify src so contextdir is added as prefix
+
+		for _, secret := range m {
+			secretOpt := strings.Split(secret, ",")
+			if len(secretOpt) > 0 {
+				modifiedOpt := []string{}
+				for _, token := range secretOpt {
+					arr := strings.SplitN(token, "=", 2)
+					if len(arr) > 1 {
+						if arr[0] == "src" {
+							modifiedSrc := fmt.Sprintf("src=%s", filepath.Join(contextDirectory, arr[1]))
+							modifiedOpt = append(modifiedOpt, modifiedSrc)
+						} else {
+							modifiedOpt = append(modifiedOpt, token)
+						}
+					}
+				}
+				secrets = append(secrets, strings.Join(modifiedOpt[:], ","))
+			}
+		}
 	}
 
 	var output string

pkg/bindings/images/build.go

@@ -5,6 +5,7 @@ import (
 	"compress/gzip"
 	"context"
 	"encoding/json"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -116,13 +117,6 @@ func Build(ctx context.Context, containerFiles []string, options entities.BuildO
 		}
 		params.Add("dnsservers", c)
 	}
-	if secrets := options.CommonBuildOpts.Secrets; len(secrets) > 0 {
-		c, err := jsoniter.MarshalToString(secrets)
-		if err != nil {
-			return nil, err
-		}
-		params.Add("secrets", c)
-	}
 	if dnsoptions := options.CommonBuildOpts.DNSOptions; len(dnsoptions) > 0 {
 		c, err := jsoniter.MarshalToString(dnsoptions)
 		if err != nil {
@@ -384,6 +378,59 @@ func Build(ctx context.Context, containerFiles []string, options entities.BuildO
 		}
 		params.Set("dockerfile", string(cFileJSON))
 	}
+
+	// build secrets are usually absolute host path or relative to context dir on host
+	// in any case move secret to current context and ship the tar.
+	if secrets := options.CommonBuildOpts.Secrets; len(secrets) > 0 {
+		secretsForRemote := []string{}
+
+		for _, secret := range secrets {
+			secretOpt := strings.Split(secret, ",")
+			if len(secretOpt) > 0 {
+				modifiedOpt := []string{}
+				for _, token := range secretOpt {
+					arr := strings.SplitN(token, "=", 2)
+					if len(arr) > 1 {
+						if arr[0] == "src" {
+							// read specified secret into a tmp file
+							// move tmp file to tar and change secret source to relative tmp file
+							tmpSecretFile, err := ioutil.TempFile(options.ContextDirectory, "podman-build-secret")
+							if err != nil {
+								return nil, err
+							}
+							defer os.Remove(tmpSecretFile.Name()) // clean up
+							defer tmpSecretFile.Close()
+							srcSecretFile, err := os.Open(arr[1])
+							if err != nil {
+								return nil, err
+							}
+							defer srcSecretFile.Close()
+							_, err = io.Copy(tmpSecretFile, srcSecretFile)
+							if err != nil {
+								return nil, err
+							}
+
+							//add tmp file to context dir
+							tarContent = append(tarContent, tmpSecretFile.Name())
+
+							modifiedSrc := fmt.Sprintf("src=%s", filepath.Base(tmpSecretFile.Name()))
+							modifiedOpt = append(modifiedOpt, modifiedSrc)
+						} else {
+							modifiedOpt = append(modifiedOpt, token)
+						}
+					}
+				}
+				secretsForRemote = append(secretsForRemote, strings.Join(modifiedOpt[:], ","))
+			}
+		}
+
+		c, err := jsoniter.MarshalToString(secretsForRemote)
+		if err != nil {
+			return nil, err
+		}
+		params.Add("secrets", c)
+	}
+
 	tarfile, err := nTar(append(excludes, dontexcludes...), tarContent...)
 	if err != nil {
 		logrus.Errorf("Cannot tar container entries %v error: %v", tarContent, err)

test/e2e/build/Dockerfile.with-multiple-secret

@@ -0,0 +1,3 @@
+FROM alpine
+RUN --mount=type=secret,id=mysecret cat /run/secrets/mysecret
+RUN --mount=type=secret,id=mysecret2 cat /run/secrets/mysecret2

test/e2e/build/Dockerfile.with-secret

@@ -0,0 +1,2 @@
+FROM alpine
+RUN --mount=type=secret,id=mysecret cat /run/secrets/mysecret

test/e2e/build/anothersecret.txt

@@ -0,0 +1 @@
+anothersecret

test/e2e/build/secret.txt

@@ -0,0 +1 @@
+somesecret

test/e2e/build_test.go

@@ -59,6 +59,29 @@ var _ = Describe("Podman build", func() {
 		Expect(session).Should(Exit(0))
 	})
 
+	It("podman build with a secret from file", func() {
+		session := podmanTest.Podman([]string{"build", "-f", "build/Dockerfile.with-secret", "-t", "secret-test", "--secret", "id=mysecret,src=build/secret.txt", "build/"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("somesecret"))
+
+		session = podmanTest.Podman([]string{"rmi", "secret-test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+	})
+
+	It("podman build with multiple secrets from files", func() {
+		session := podmanTest.Podman([]string{"build", "-f", "build/Dockerfile.with-multiple-secret", "-t", "multiple-secret-test", "--secret", "id=mysecret,src=build/secret.txt", "--secret", "id=mysecret2,src=build/anothersecret.txt", "build/"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+		Expect(session.OutputToString()).To(ContainSubstring("somesecret"))
+		Expect(session.OutputToString()).To(ContainSubstring("anothersecret"))
+
+		session = podmanTest.Podman([]string{"rmi", "multiple-secret-test"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).Should(Exit(0))
+	})
+
 	It("podman build with logfile", func() {
 		logfile := filepath.Join(podmanTest.TempDir, "logfile")
 		session := podmanTest.Podman([]string{"build", "--pull-never", "--tag", "test", "--logfile", logfile, "build/basicalpine"})