automation-tests/image/docker/docker_image_dest.go

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package docker
import (
"bytes"
"context"
"crypto/rand"
"encoding/json"
"errors"
"fmt"
"io"
"maps"
"net/http"
"net/url"
"os"
"path/filepath"
"slices"
"strings"
"github.com/containers/image/v5/docker/reference"
"github.com/containers/image/v5/internal/blobinfocache"
"github.com/containers/image/v5/internal/imagedestination/impl"
"github.com/containers/image/v5/internal/imagedestination/stubs"
"github.com/containers/image/v5/internal/iolimits"
"github.com/containers/image/v5/internal/private"
"github.com/containers/image/v5/internal/putblobdigest"
"github.com/containers/image/v5/internal/set"
"github.com/containers/image/v5/internal/signature"
"github.com/containers/image/v5/internal/streamdigest"
"github.com/containers/image/v5/internal/uploadreader"
"github.com/containers/image/v5/manifest"
"github.com/containers/image/v5/pkg/blobinfocache/none"
compressiontypes "github.com/containers/image/v5/pkg/compression/types"
"github.com/containers/image/v5/types"
"github.com/docker/distribution/registry/api/errcode"
v2 "github.com/docker/distribution/registry/api/v2"
"github.com/opencontainers/go-digest"
imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/sirupsen/logrus"
)
type dockerImageDestination struct {
impl.Compat
impl.PropertyMethodsInitialize
stubs.IgnoresOriginalOCIConfig
stubs.NoPutBlobPartialInitialize
ref dockerReference
c *dockerClient
// State
manifestDigest digest.Digest // or "" if not yet known.
}
// newImageDestination creates a new ImageDestination for the specified image reference.
func newImageDestination(sys *types.SystemContext, ref dockerReference) (private.ImageDestination, error) {
registryConfig, err := loadRegistryConfiguration(sys)
if err != nil {
return nil, err
}
c, err := newDockerClientFromRef(sys, ref, registryConfig, true, "pull,push")
if err != nil {
return nil, err
}
mimeTypes := []string{
imgspecv1.MediaTypeImageManifest,
manifest.DockerV2Schema2MediaType,
imgspecv1.MediaTypeImageIndex,
manifest.DockerV2ListMediaType,
}
if c.sys == nil || !c.sys.DockerDisableDestSchema1MIMETypes {
mimeTypes = append(mimeTypes, manifest.DockerV2Schema1SignedMediaType, manifest.DockerV2Schema1MediaType)
}
dest := &dockerImageDestination{
PropertyMethodsInitialize: impl.PropertyMethods(impl.Properties{
SupportedManifestMIMETypes: mimeTypes,
DesiredLayerCompression: types.Compress,
MustMatchRuntimeOS: false,
IgnoresEmbeddedDockerReference: false, // We do want the manifest updated; older registry versions refuse manifests if the embedded reference does not match.
HasThreadSafePutBlob: true,
}),
NoPutBlobPartialInitialize: stubs.NoPutBlobPartial(ref),
ref: ref,
c: c,
}
dest.Compat = impl.AddCompat(dest)
return dest, nil
}
// Reference returns the reference used to set up this destination. Note that this should directly correspond to user's intent,
// e.g. it should use the public hostname instead of the result of resolving CNAMEs or following redirects.
func (d *dockerImageDestination) Reference() types.ImageReference {
return d.ref
}
// Close removes resources associated with an initialized ImageDestination, if any.
func (d *dockerImageDestination) Close() error {
return d.c.Close()
}
// SupportsSignatures returns an error (to be displayed to the user) if the destination certainly can't store signatures.
// Note: It is still possible for PutSignatures to fail if SupportsSignatures returns nil.
func (d *dockerImageDestination) SupportsSignatures(ctx context.Context) error {
if err := d.c.detectProperties(ctx); err != nil {
return err
}
switch {
case d.c.supportsSignatures:
return nil
case d.c.signatureBase != nil:
return nil
default:
return errors.New("Internal error: X-Registry-Supports-Signatures extension not supported, and lookaside should not be empty configuration")
}
}
// AcceptsForeignLayerURLs returns false iff foreign layers in manifest should be actually
// uploaded to the image destination, true otherwise.
func (d *dockerImageDestination) AcceptsForeignLayerURLs() bool {
return true
}
// sizeCounter is an io.Writer which only counts the total size of its input.
type sizeCounter struct{ size int64 }
func (c *sizeCounter) Write(p []byte) (n int, err error) {
c.size += int64(len(p))
return len(p), nil
}
// PutBlobWithOptions writes contents of stream and returns data representing the result.
// inputInfo.Digest can be optionally provided if known; if provided, and stream is read to the end without error, the digest MUST match the stream contents.
// inputInfo.Size is the expected length of stream, if known.
// inputInfo.MediaType describes the blob format, if known.
// WARNING: The contents of stream are being verified on the fly. Until stream.Read() returns io.EOF, the contents of the data SHOULD NOT be available
// to any other readers for download using the supplied digest.
// If stream.Read() at any time, ESPECIALLY at end of input, returns an error, PutBlobWithOptions MUST 1) fail, and 2) delete any data stored so far.
func (d *dockerImageDestination) PutBlobWithOptions(ctx context.Context, stream io.Reader, inputInfo types.BlobInfo, options private.PutBlobOptions) (private.UploadedBlob, error) {
// If requested, precompute the blob digest to prevent uploading layers that already exist on the registry.
// This functionality is particularly useful when BlobInfoCache has not been populated with compressed digests,
// the source blob is uncompressed, and the destination blob is being compressed "on the fly".
if inputInfo.Digest == "" && d.c.sys != nil && d.c.sys.DockerRegistryPushPrecomputeDigests {
logrus.Debugf("Precomputing digest layer for %s", reference.Path(d.ref.ref))
streamCopy, cleanup, err := streamdigest.ComputeBlobInfo(d.c.sys, stream, &inputInfo)
if err != nil {
return private.UploadedBlob{}, err
}
defer cleanup()
stream = streamCopy
}
if inputInfo.Digest != "" {
// This should not really be necessary, at least the copy code calls TryReusingBlob automatically.
// Still, we need to check, if only because the "initiate upload" endpoint does not have a documented "blob already exists" return value.
haveBlob, reusedInfo, err := d.tryReusingExactBlob(ctx, inputInfo, options.Cache)
if err != nil {
return private.UploadedBlob{}, err
}
if haveBlob {
return private.UploadedBlob{Digest: reusedInfo.Digest, Size: reusedInfo.Size}, nil
}
}
// FIXME? Chunked upload, progress reporting, etc.
uploadPath := fmt.Sprintf(blobUploadPath, reference.Path(d.ref.ref))
logrus.Debugf("Uploading %s", uploadPath)
res, err := d.c.makeRequest(ctx, http.MethodPost, uploadPath, nil, nil, v2Auth, nil)
if err != nil {
return private.UploadedBlob{}, err
}
defer res.Body.Close()
if res.StatusCode != http.StatusAccepted {
logrus.Debugf("Error initiating layer upload, response %#v", *res)
return private.UploadedBlob{}, fmt.Errorf("initiating layer upload to %s in %s: %w", uploadPath, d.c.registry, registryHTTPResponseToError(res))
}
uploadLocation, err := res.Location()
if err != nil {
return private.UploadedBlob{}, fmt.Errorf("determining upload URL: %w", err)
}
digester, stream := putblobdigest.DigestIfCanonicalUnknown(stream, inputInfo)
sizeCounter := &sizeCounter{}
stream = io.TeeReader(stream, sizeCounter)
uploadLocation, err = func() (*url.URL, error) { // A scope for defer
uploadReader := uploadreader.NewUploadReader(stream)
// This error text should never be user-visible, we terminate only after makeRequestToResolvedURL
// returns, so there isnt a way for the error text to be provided to any of our callers.
defer uploadReader.Terminate(errors.New("Reading data from an already terminated upload"))
res, err = d.c.makeRequestToResolvedURL(ctx, http.MethodPatch, uploadLocation, map[string][]string{"Content-Type": {"application/octet-stream"}}, uploadReader, inputInfo.Size, v2Auth, nil)
if err != nil {
logrus.Debugf("Error uploading layer chunked %v", err)
return nil, err
}
defer res.Body.Close()
if !successStatus(res.StatusCode) {
return nil, fmt.Errorf("uploading layer chunked: %w", registryHTTPResponseToError(res))
}
uploadLocation, err := res.Location()
if err != nil {
return nil, fmt.Errorf("determining upload URL: %w", err)
}
return uploadLocation, nil
}()
if err != nil {
return private.UploadedBlob{}, err
}
blobDigest := digester.Digest()
// FIXME: DELETE uploadLocation on failure (does not really work in docker/distribution servers, which incorrectly require the "delete" action in the token's scope)
locationQuery := uploadLocation.Query()
locationQuery.Set("digest", blobDigest.String())
uploadLocation.RawQuery = locationQuery.Encode()
res, err = d.c.makeRequestToResolvedURL(ctx, http.MethodPut, uploadLocation, map[string][]string{"Content-Type": {"application/octet-stream"}}, nil, -1, v2Auth, nil)
if err != nil {
return private.UploadedBlob{}, err
}
defer res.Body.Close()
if res.StatusCode != http.StatusCreated {
logrus.Debugf("Error uploading layer, response %#v", *res)
return private.UploadedBlob{}, fmt.Errorf("uploading layer to %s: %w", uploadLocation, registryHTTPResponseToError(res))
}
logrus.Debugf("Upload of layer %s complete", blobDigest)
options.Cache.RecordKnownLocation(d.ref.Transport(), bicTransportScope(d.ref), blobDigest, newBICLocationReference(d.ref))
return private.UploadedBlob{Digest: blobDigest, Size: sizeCounter.size}, nil
}
// blobExists returns true iff repo contains a blob with digest, and if so, also its size.
// If the destination does not contain the blob, or it is unknown, blobExists ordinarily returns (false, -1, nil);
// it returns a non-nil error only on an unexpected failure.
func (d *dockerImageDestination) blobExists(ctx context.Context, repo reference.Named, digest digest.Digest, extraScope *authScope) (bool, int64, error) {
if err := digest.Validate(); err != nil { // Make sure digest.String() does not contain any unexpected characters
return false, -1, err
}
checkPath := fmt.Sprintf(blobsPath, reference.Path(repo), digest.String())
logrus.Debugf("Checking %s", checkPath)
res, err := d.c.makeRequest(ctx, http.MethodHead, checkPath, nil, nil, v2Auth, extraScope)
if err != nil {
return false, -1, err
}
defer res.Body.Close()
switch res.StatusCode {
case http.StatusOK:
size, err := getBlobSize(res)
if err != nil {
return false, -1, fmt.Errorf("determining size of blob %s in %s: %w", digest, repo.Name(), err)
}
logrus.Debugf("... already exists")
return true, size, nil
case http.StatusUnauthorized:
logrus.Debugf("... not authorized")
return false, -1, fmt.Errorf("checking whether a blob %s exists in %s: %w", digest, repo.Name(), registryHTTPResponseToError(res))
case http.StatusNotFound:
logrus.Debugf("... not present")
return false, -1, nil
default:
return false, -1, fmt.Errorf("checking whether a blob %s exists in %s: %w", digest, repo.Name(), registryHTTPResponseToError(res))
}
}
// mountBlob tries to mount blob srcDigest from srcRepo to the current destination.
func (d *dockerImageDestination) mountBlob(ctx context.Context, srcRepo reference.Named, srcDigest digest.Digest, extraScope *authScope) error {
u := url.URL{
Path: fmt.Sprintf(blobUploadPath, reference.Path(d.ref.ref)),
RawQuery: url.Values{
"mount": {srcDigest.String()},
"from": {reference.Path(srcRepo)},
}.Encode(),
}
logrus.Debugf("Trying to mount %s", u.Redacted())
res, err := d.c.makeRequest(ctx, http.MethodPost, u.String(), nil, nil, v2Auth, extraScope)
if err != nil {
return err
}
defer res.Body.Close()
switch res.StatusCode {
case http.StatusCreated:
logrus.Debugf("... mount OK")
return nil
case http.StatusAccepted:
// Oops, the mount was ignored - either the registry does not support that yet, or the blob does not exist; the registry has started an ordinary upload process.
// Abort, and let the ultimate caller do an upload when its ready, instead.
// NOTE: This does not really work in docker/distribution servers, which incorrectly require the "delete" action in the token's scope, and is thus entirely untested.
uploadLocation, err := res.Location()
if err != nil {
return fmt.Errorf("determining upload URL after a mount attempt: %w", err)
}
logrus.Debugf("... started an upload instead of mounting, trying to cancel at %s", uploadLocation.Redacted())
res2, err := d.c.makeRequestToResolvedURL(ctx, http.MethodDelete, uploadLocation, nil, nil, -1, v2Auth, extraScope)
if err != nil {
logrus.Debugf("Error trying to cancel an inadvertent upload: %s", err)
} else {
defer res2.Body.Close()
if res2.StatusCode != http.StatusNoContent {
logrus.Debugf("Error trying to cancel an inadvertent upload, status %s", http.StatusText(res.StatusCode))
}
}
// Anyway, if canceling the upload fails, ignore it and return the more important error:
return fmt.Errorf("Mounting %s from %s to %s started an upload instead", srcDigest, srcRepo.Name(), d.ref.ref.Name())
default:
logrus.Debugf("Error mounting, response %#v", *res)
return fmt.Errorf("mounting %s from %s to %s: %w", srcDigest, srcRepo.Name(), d.ref.ref.Name(), registryHTTPResponseToError(res))
}
}
// tryReusingExactBlob is a subset of TryReusingBlob which _only_ looks for exactly the specified
// blob in the current repository, with no cross-repo reuse or mounting; cache may be updated, it is not read.
// The caller must ensure info.Digest is set.
func (d *dockerImageDestination) tryReusingExactBlob(ctx context.Context, info types.BlobInfo, cache blobinfocache.BlobInfoCache2) (bool, private.ReusedBlob, error) {
exists, size, err := d.blobExists(ctx, d.ref.ref, info.Digest, nil)
if err != nil {
return false, private.ReusedBlob{}, err
}
if exists {
cache.RecordKnownLocation(d.ref.Transport(), bicTransportScope(d.ref), info.Digest, newBICLocationReference(d.ref))
return true, private.ReusedBlob{Digest: info.Digest, Size: size}, nil
}
return false, private.ReusedBlob{}, nil
}
func optionalCompressionName(algo *compressiontypes.Algorithm) string {
if algo != nil {
return algo.Name()
}
return "nil"
}
// TryReusingBlobWithOptions checks whether the transport already contains, or can efficiently reuse, a blob, and if so, applies it to the current destination
// (e.g. if the blob is a filesystem layer, this signifies that the changes it describes need to be applied again when composing a filesystem tree).
// info.Digest must not be empty.
// If the blob has been successfully reused, returns (true, info, nil).
// If the transport can not reuse the requested blob, TryReusingBlob returns (false, {}, nil); it returns a non-nil error only on an unexpected failure.
func (d *dockerImageDestination) TryReusingBlobWithOptions(ctx context.Context, info types.BlobInfo, options private.TryReusingBlobOptions) (bool, private.ReusedBlob, error) {
if info.Digest == "" {
return false, private.ReusedBlob{}, errors.New("Can not check for a blob with unknown digest")
}
originalCandidateKnownToBeMissing := false
if impl.OriginalCandidateMatchesTryReusingBlobOptions(options) {
// First, check whether the blob happens to already exist at the destination.
haveBlob, reusedInfo, err := d.tryReusingExactBlob(ctx, info, options.Cache)
if err != nil {
return false, private.ReusedBlob{}, err
}
if haveBlob {
return true, reusedInfo, nil
}
originalCandidateKnownToBeMissing = true
} else {
logrus.Debugf("Ignoring exact blob match, compression %s does not match required %s or MIME types %#v",
optionalCompressionName(options.OriginalCompression), optionalCompressionName(options.RequiredCompression), options.PossibleManifestFormats)
// We can get here with a blob detected to be zstd when the user wants a zstd:chunked.
// In that case we keep originalCandiateKnownToBeMissing = false, so that if we find
// a BIC entry for this blob, we do use that entry and return a zstd:chunked entry
// with the BICs annotations.
// This is not quite correct, it only works if the BIC also contains an acceptable _location_.
// Ideally, we could look up just the compression algorithm/annotations for info.digest,
// and use it even if no location candidate exists and the original dandidate is present.
}
// Then try reusing blobs from other locations.
candidates := options.Cache.CandidateLocations2(d.ref.Transport(), bicTransportScope(d.ref), info.Digest, blobinfocache.CandidateLocations2Options{
CanSubstitute: options.CanSubstitute,
PossibleManifestFormats: options.PossibleManifestFormats,
RequiredCompression: options.RequiredCompression,
})
for _, candidate := range candidates {
var candidateRepo reference.Named
if !candidate.UnknownLocation {
var err error
candidateRepo, err = parseBICLocationReference(candidate.Location)
if err != nil {
logrus.Debugf("Error parsing BlobInfoCache location reference: %s", err)
continue
}
if candidate.CompressionAlgorithm != nil {
logrus.Debugf("Trying to reuse blob with cached digest %s compressed with %s in destination repo %s", candidate.Digest.String(), candidate.CompressionAlgorithm.Name(), candidateRepo.Name())
} else {
logrus.Debugf("Trying to reuse blob with cached digest %s in destination repo %s", candidate.Digest.String(), candidateRepo.Name())
}
// Sanity checks:
if reference.Domain(candidateRepo) != reference.Domain(d.ref.ref) {
// OCI distribution spec 1.1 allows mounting blobs without specifying the source repo
// (the "from" parameter); in that case we might try to use these candidates as well.
//
// OTOH that would mean we cant do the “blobExists” check, and if there is no match
// we could get an upload request that we would have to cancel.
logrus.Debugf("... Internal error: domain %s does not match destination %s", reference.Domain(candidateRepo), reference.Domain(d.ref.ref))
continue
}
} else {
if candidate.CompressionAlgorithm != nil {
logrus.Debugf("Trying to reuse blob with cached digest %s compressed with %s with no location match, checking current repo", candidate.Digest.String(), candidate.CompressionAlgorithm.Name())
} else {
logrus.Debugf("Trying to reuse blob with cached digest %s in destination repo with no location match, checking current repo", candidate.Digest.String())
}
// This digest is a known variant of this blob but we dont
// have a recorded location in this registry, lets try looking
// for it in the current repo.
candidateRepo = reference.TrimNamed(d.ref.ref)
}
if originalCandidateKnownToBeMissing &&
candidateRepo.Name() == d.ref.ref.Name() && candidate.Digest == info.Digest {
logrus.Debug("... Already tried the primary destination")
continue
}
// Whatever happens here, don't abort the entire operation. It's likely we just don't have permissions, and if it is a critical network error, we will find out soon enough anyway.
// Checking candidateRepo, and mounting from it, requires an
// expanded token scope.
extraScope := &authScope{
resourceType: "repository",
remoteName: reference.Path(candidateRepo),
actions: "pull",
}
// This existence check is not, strictly speaking, necessary: We only _really_ need it to get the blob size, and we could record that in the cache instead.
// But a "failed" d.mountBlob currently leaves around an unterminated server-side upload, which we would try to cancel.
// So, without this existence check, it would be 1 request on success, 2 requests on failure; with it, it is 2 requests on success, 1 request on failure.
// On success we avoid the actual costly upload; so, in a sense, the success case is "free", but failures are always costly.
// Even worse, docker/distribution does not actually reasonably implement canceling uploads
// (it would require a "delete" action in the token, and Quay does not give that to anyone, so we can't ask);
// so, be a nice client and don't create unnecessary upload sessions on the server.
exists, size, err := d.blobExists(ctx, candidateRepo, candidate.Digest, extraScope)
if err != nil {
logrus.Debugf("... Failed: %v", err)
continue
}
if !exists {
// FIXME? Should we drop the blob from cache here (and elsewhere?)?
continue // logrus.Debug() already happened in blobExists
}
if candidateRepo.Name() != d.ref.ref.Name() {
if err := d.mountBlob(ctx, candidateRepo, candidate.Digest, extraScope); err != nil {
logrus.Debugf("... Mount failed: %v", err)
continue
}
}
options.Cache.RecordKnownLocation(d.ref.Transport(), bicTransportScope(d.ref), candidate.Digest, newBICLocationReference(d.ref))
return true, private.ReusedBlob{
Digest: candidate.Digest,
Size: size,
CompressionOperation: candidate.CompressionOperation,
CompressionAlgorithm: candidate.CompressionAlgorithm,
CompressionAnnotations: candidate.CompressionAnnotations,
}, nil
}
return false, private.ReusedBlob{}, nil
}
// PutManifest writes manifest to the destination.
// When the primary manifest is a manifest list, if instanceDigest is nil, we're saving the list
// itself, else instanceDigest contains a digest of the specific manifest instance to overwrite the
// manifest for; when the primary manifest is not a manifest list, instanceDigest should always be nil.
// FIXME? This should also receive a MIME type if known, to differentiate between schema versions.
// If the destination is in principle available, refuses this manifest type (e.g. it does not recognize the schema),
// but may accept a different manifest type, the returned error must be an ManifestTypeRejectedError.
func (d *dockerImageDestination) PutManifest(ctx context.Context, m []byte, instanceDigest *digest.Digest) error {
var refTail string
// If d.ref.isUnknownDigest=true, then we push without a tag, so get the
// digest that will be used
if d.ref.isUnknownDigest {
digest, err := manifest.Digest(m)
if err != nil {
return err
}
refTail = digest.String()
} else if instanceDigest != nil {
// If the instanceDigest is provided, then use it as the refTail, because the reference,
// whether it includes a tag or a digest, refers to the list as a whole, and not this
// particular instance.
refTail = instanceDigest.String()
// Double-check that the manifest we've been given matches the digest we've been given.
// This also validates the format of instanceDigest.
matches, err := manifest.MatchesDigest(m, *instanceDigest)
if err != nil {
return fmt.Errorf("digesting manifest in PutManifest: %w", err)
}
if !matches {
manifestDigest, merr := manifest.Digest(m)
if merr != nil {
return fmt.Errorf("Attempted to PutManifest using an explicitly specified digest (%q) that didn't match the manifest's digest: %w", instanceDigest.String(), merr)
}
return fmt.Errorf("Attempted to PutManifest using an explicitly specified digest (%q) that didn't match the manifest's digest (%q)", instanceDigest.String(), manifestDigest.String())
}
} else {
// Compute the digest of the main manifest, or the list if it's a list, so that we
// have a digest value to use if we're asked to save a signature for the manifest.
digest, err := manifest.Digest(m)
if err != nil {
return err
}
d.manifestDigest = digest
// The refTail should be either a digest (which we expect to match the value we just
// computed) or a tag name.
refTail, err = d.ref.tagOrDigest()
if err != nil {
return err
}
}
return d.uploadManifest(ctx, m, refTail)
}
// uploadManifest writes manifest to tagOrDigest.
func (d *dockerImageDestination) uploadManifest(ctx context.Context, m []byte, tagOrDigest string) error {
path := fmt.Sprintf(manifestPath, reference.Path(d.ref.ref), tagOrDigest)
headers := map[string][]string{}
mimeType := manifest.GuessMIMEType(m)
if mimeType != "" {
headers["Content-Type"] = []string{mimeType}
}
res, err := d.c.makeRequest(ctx, http.MethodPut, path, headers, bytes.NewReader(m), v2Auth, nil)
if err != nil {
return err
}
defer res.Body.Close()
if !successStatus(res.StatusCode) {
rawErr := registryHTTPResponseToError(res)
err := fmt.Errorf("uploading manifest %s to %s: %w", tagOrDigest, d.ref.ref.Name(), rawErr)
if isManifestInvalidError(rawErr) {
err = types.ManifestTypeRejectedError{Err: err}
}
return err
}
// A HTTP server may not be a registry at all, and just return 200 OK to everything
// (in particular that can fairly easily happen after tearing down a website and
// replacing it with a global 302 redirect to a new website, completely ignoring the
// path in the request); in that case we could “succeed” uploading a whole image.
// With docker/distribution we could rely on a Docker-Content-Digest header being present
// (because docker/distribution/registry/client has been failing uploads if it was missing),
// but that has been defined as explicitly optional by
// https://github.com/opencontainers/distribution-spec/blob/ec90a2af85fe4d612cf801e1815b95bfa40ae72b/spec.md#legacy-docker-support-http-headers
// So, just note the missing header in a debug log.
if v := res.Header.Values("Docker-Content-Digest"); len(v) == 0 {
logrus.Debugf("Manifest upload response didnt contain a Docker-Content-Digest header, it might not be a container registry")
}
return nil
}
// successStatus returns true if the argument is a successful HTTP response
// code (in the range 200 - 399 inclusive).
func successStatus(status int) bool {
return status >= 200 && status <= 399
}
// isManifestInvalidError returns true iff err from registryHTTPResponseToError is a “manifest invalid” error.
func isManifestInvalidError(err error) bool {
var ec errcode.ErrorCoder
if ok := errors.As(err, &ec); !ok {
return false
}
switch ec.ErrorCode() {
// ErrorCodeManifestInvalid is returned by OpenShift with acceptschema2=false.
case v2.ErrorCodeManifestInvalid:
return true
// ErrorCodeTagInvalid is returned by docker/distribution (at least as of commit ec87e9b6971d831f0eff752ddb54fb64693e51cd)
// when uploading to a tag (because it cant find a matching tag inside the manifest)
case v2.ErrorCodeTagInvalid:
return true
// ErrorCodeUnsupported with 'Invalid JSON syntax' is returned by AWS ECR when
// uploading an OCI manifest that is (correctly, according to the spec) missing
// a top-level media type. See libpod issue #1719
// FIXME: remove this case when ECR behavior is fixed
case errcode.ErrorCodeUnsupported:
return strings.Contains(err.Error(), "Invalid JSON syntax")
default:
return false
}
}
// PutSignaturesWithFormat writes a set of signatures to the destination.
// If instanceDigest is not nil, it contains a digest of the specific manifest instance to write or overwrite the signatures for
// (when the primary manifest is a manifest list); this should always be nil if the primary manifest is not a manifest list.
// MUST be called after PutManifest (signatures may reference manifest contents).
func (d *dockerImageDestination) PutSignaturesWithFormat(ctx context.Context, signatures []signature.Signature, instanceDigest *digest.Digest) error {
if instanceDigest == nil {
if d.manifestDigest == "" {
// This shouldnt happen, ImageDestination users are required to call PutManifest before PutSignatures
return errors.New("Unknown manifest digest, can't add signatures")
}
instanceDigest = &d.manifestDigest
}
sigstoreSignatures := []signature.Sigstore{}
otherSignatures := []signature.Signature{}
for _, sig := range signatures {
if sigstoreSig, ok := sig.(signature.Sigstore); ok {
sigstoreSignatures = append(sigstoreSignatures, sigstoreSig)
} else {
otherSignatures = append(otherSignatures, sig)
}
}
// Only write sigstores signatures to sigstores attachments. We _could_ store them to lookaside
// instead, but that would probably be rather surprising.
// FIXME: So should we enable sigstores in all cases? Or write in all cases, but opt-in to read?
if len(sigstoreSignatures) != 0 {
if err := d.putSignaturesToSigstoreAttachments(ctx, sigstoreSignatures, *instanceDigest); err != nil {
return err
}
}
if len(otherSignatures) != 0 {
if err := d.c.detectProperties(ctx); err != nil {
return err
}
switch {
case d.c.supportsSignatures:
if err := d.putSignaturesToAPIExtension(ctx, signatures, *instanceDigest); err != nil {
return err
}
case d.c.signatureBase != nil:
if err := d.putSignaturesToLookaside(signatures, *instanceDigest); err != nil {
return err
}
default:
return errors.New("Internal error: X-Registry-Supports-Signatures extension not supported, and lookaside should not be empty configuration")
}
}
return nil
}
// putSignaturesToLookaside implements PutSignaturesWithFormat() from the lookaside location configured in s.c.signatureBase,
// which is not nil, for a manifest with manifestDigest.
func (d *dockerImageDestination) putSignaturesToLookaside(signatures []signature.Signature, manifestDigest digest.Digest) error {
// FIXME? This overwrites files one at a time, definitely not atomic.
// A failure when updating signatures with a reordered copy could lose some of them.
// Skip dealing with the manifest digest if not necessary.
if len(signatures) == 0 {
return nil
}
// NOTE: Keep this in sync with docs/signature-protocols.md!
for i, signature := range signatures {
sigURL, err := lookasideStorageURL(d.c.signatureBase, manifestDigest, i)
if err != nil {
return err
}
if err := d.putOneSignature(sigURL, signature); err != nil {
return err
}
}
// Remove any other signatures, if present.
// We stop at the first missing signature; if a previous deleting loop aborted
// prematurely, this may not clean up all of them, but one missing signature
// is enough for dockerImageSource to stop looking for other signatures, so that
// is sufficient.
for i := len(signatures); ; i++ {
sigURL, err := lookasideStorageURL(d.c.signatureBase, manifestDigest, i)
if err != nil {
return err
}
missing, err := d.c.deleteOneSignature(sigURL)
if err != nil {
return err
}
if missing {
break
}
}
return nil
}
// putOneSignature stores sig to sigURL.
// NOTE: Keep this in sync with docs/signature-protocols.md!
func (d *dockerImageDestination) putOneSignature(sigURL *url.URL, sig signature.Signature) error {
switch sigURL.Scheme {
case "file":
logrus.Debugf("Writing to %s", sigURL.Path)
err := os.MkdirAll(filepath.Dir(sigURL.Path), 0755)
if err != nil {
return err
}
blob, err := signature.Blob(sig)
if err != nil {
return err
}
err = os.WriteFile(sigURL.Path, blob, 0644)
if err != nil {
return err
}
return nil
case "http", "https":
return fmt.Errorf("Writing directly to a %s lookaside %s is not supported. Configure a lookaside-staging: location", sigURL.Scheme, sigURL.Redacted())
default:
return fmt.Errorf("Unsupported scheme when writing signature to %s", sigURL.Redacted())
}
}
func (d *dockerImageDestination) putSignaturesToSigstoreAttachments(ctx context.Context, signatures []signature.Sigstore, manifestDigest digest.Digest) error {
if !d.c.useSigstoreAttachments {
return errors.New("writing sigstore attachments is disabled by configuration")
}
ociManifest, err := d.c.getSigstoreAttachmentManifest(ctx, d.ref, manifestDigest)
if err != nil {
return err
}
var ociConfig imgspecv1.Image // Most fields empty by default
if ociManifest == nil {
ociManifest = manifest.OCI1FromComponents(imgspecv1.Descriptor{
MediaType: imgspecv1.MediaTypeImageConfig,
Digest: "", // We will fill this in later.
Size: 0,
}, nil)
ociConfig.RootFS.Type = "layers"
} else {
logrus.Debugf("Fetching sigstore attachment config %s", ociManifest.Config.Digest.String())
// We dont benefit from a real BlobInfoCache here because we never try to reuse/mount configs.
configBlob, err := d.c.getOCIDescriptorContents(ctx, d.ref, ociManifest.Config, iolimits.MaxConfigBodySize,
none.NoCache)
if err != nil {
return err
}
if err := json.Unmarshal(configBlob, &ociConfig); err != nil {
return fmt.Errorf("parsing sigstore attachment config %s in %s: %w", ociManifest.Config.Digest.String(),
d.ref.ref.Name(), err)
}
}
// To make sure we can safely append to the slices of ociManifest, without adding a remote dependency on the code that creates it.
ociManifest.Layers = slices.Clone(ociManifest.Layers)
// We dont need to ^^^ for ociConfig.RootFS.DiffIDs because we have created it empty ourselves, and json.Unmarshal is documented to append() to
// the slice in the original object (or in a newly allocated object).
for _, sig := range signatures {
mimeType := sig.UntrustedMIMEType()
payloadBlob := sig.UntrustedPayload()
annotations := sig.UntrustedAnnotations()
alreadyOnRegistry := false
for _, layer := range ociManifest.Layers {
if layerMatchesSigstoreSignature(layer, mimeType, payloadBlob, annotations) {
logrus.Debugf("Signature with digest %s already exists on the registry", layer.Digest.String())
alreadyOnRegistry = true
break
}
}
if alreadyOnRegistry {
continue
}
// We dont benefit from a real BlobInfoCache here because we never try to reuse/mount attachment payloads.
// That might eventually need to change if payloads grow to be not just signatures, but something
// significantly large.
sigDesc, err := d.putBlobBytesAsOCI(ctx, payloadBlob, mimeType, private.PutBlobOptions{
Cache: none.NoCache,
IsConfig: false,
EmptyLayer: false,
LayerIndex: nil,
})
if err != nil {
return err
}
sigDesc.Annotations = annotations
ociManifest.Layers = append(ociManifest.Layers, sigDesc)
ociConfig.RootFS.DiffIDs = append(ociConfig.RootFS.DiffIDs, sigDesc.Digest)
logrus.Debugf("Adding new signature, digest %s", sigDesc.Digest.String())
}
configBlob, err := json.Marshal(ociConfig)
if err != nil {
return err
}
logrus.Debugf("Uploading updated sigstore attachment config")
// We dont benefit from a real BlobInfoCache here because we never try to reuse/mount configs.
configDesc, err := d.putBlobBytesAsOCI(ctx, configBlob, imgspecv1.MediaTypeImageConfig, private.PutBlobOptions{
Cache: none.NoCache,
IsConfig: true,
EmptyLayer: false,
LayerIndex: nil,
})
if err != nil {
return err
}
ociManifest.Config = configDesc
manifestBlob, err := ociManifest.Serialize()
if err != nil {
return err
}
attachmentTag, err := sigstoreAttachmentTag(manifestDigest)
if err != nil {
return err
}
logrus.Debugf("Uploading sigstore attachment manifest")
return d.uploadManifest(ctx, manifestBlob, attachmentTag)
}
func layerMatchesSigstoreSignature(layer imgspecv1.Descriptor, mimeType string,
payloadBlob []byte, annotations map[string]string) bool {
if layer.MediaType != mimeType ||
layer.Size != int64(len(payloadBlob)) ||
// This is not quite correct, we should use the layers digest algorithm.
// But right now we dont want to deal with corner cases like bad digest formats
// or unavailable algorithms; in the worst case we end up with duplicate signature
// entries.
layer.Digest.String() != digest.FromBytes(payloadBlob).String() ||
!maps.Equal(layer.Annotations, annotations) {
return false
}
return true
}
// putBlobBytesAsOCI uploads a blob with the specified contents, and returns an appropriate
// OCI descriptor.
func (d *dockerImageDestination) putBlobBytesAsOCI(ctx context.Context, contents []byte, mimeType string, options private.PutBlobOptions) (imgspecv1.Descriptor, error) {
blobDigest := digest.FromBytes(contents)
info, err := d.PutBlobWithOptions(ctx, bytes.NewReader(contents),
types.BlobInfo{
Digest: blobDigest,
Size: int64(len(contents)),
MediaType: mimeType,
}, options)
if err != nil {
return imgspecv1.Descriptor{}, fmt.Errorf("writing blob %s: %w", blobDigest.String(), err)
}
return imgspecv1.Descriptor{
MediaType: mimeType,
Digest: info.Digest,
Size: info.Size,
}, nil
}
// deleteOneSignature deletes a signature from sigURL, if it exists.
// If it successfully determines that the signature does not exist, returns (true, nil)
// NOTE: Keep this in sync with docs/signature-protocols.md!
func (c *dockerClient) deleteOneSignature(sigURL *url.URL) (missing bool, err error) {
switch sigURL.Scheme {
case "file":
logrus.Debugf("Deleting %s", sigURL.Path)
err := os.Remove(sigURL.Path)
if err != nil && os.IsNotExist(err) {
return true, nil
}
return false, err
case "http", "https":
return false, fmt.Errorf("Writing directly to a %s lookaside %s is not supported. Configure a lookaside-staging: location", sigURL.Scheme, sigURL.Redacted())
default:
return false, fmt.Errorf("Unsupported scheme when deleting signature from %s", sigURL.Redacted())
}
}
// putSignaturesToAPIExtension implements PutSignaturesWithFormat() using the X-Registry-Supports-Signatures API extension,
// for a manifest with manifestDigest.
func (d *dockerImageDestination) putSignaturesToAPIExtension(ctx context.Context, signatures []signature.Signature, manifestDigest digest.Digest) error {
// Skip dealing with the manifest digest, or reading the old state, if not necessary.
if len(signatures) == 0 {
return nil
}
// Because image signatures are a shared resource in Atomic Registry, the default upload
// always adds signatures. Eventually we should also allow removing signatures,
// but the X-Registry-Supports-Signatures API extension does not support that yet.
existingSignatures, err := d.c.getExtensionsSignatures(ctx, d.ref, manifestDigest)
if err != nil {
return err
}
existingSigNames := set.New[string]()
for _, sig := range existingSignatures.Signatures {
existingSigNames.Add(sig.Name)
}
for _, newSigWithFormat := range signatures {
newSigSimple, ok := newSigWithFormat.(signature.SimpleSigning)
if !ok {
return signature.UnsupportedFormatError(newSigWithFormat)
}
newSig := newSigSimple.UntrustedSignature()
if slices.ContainsFunc(existingSignatures.Signatures, func(existingSig extensionSignature) bool {
return existingSig.Version == extensionSignatureSchemaVersion && existingSig.Type == extensionSignatureTypeAtomic && bytes.Equal(existingSig.Content, newSig)
}) {
continue
}
// The API expect us to invent a new unique name. This is racy, but hopefully good enough.
var signatureName string
for {
randBytes := make([]byte, 16)
n, err := rand.Read(randBytes)
if err != nil || n != 16 {
return fmt.Errorf("generating random signature len %d: %w", n, err)
}
signatureName = fmt.Sprintf("%s@%032x", manifestDigest.String(), randBytes)
if !existingSigNames.Contains(signatureName) {
break
}
}
sig := extensionSignature{
Version: extensionSignatureSchemaVersion,
Name: signatureName,
Type: extensionSignatureTypeAtomic,
Content: newSig,
}
body, err := json.Marshal(sig)
if err != nil {
return err
}
// manifestDigest is known to be valid because it was not rejected by getExtensionsSignatures above.
path := fmt.Sprintf(extensionsSignaturePath, reference.Path(d.ref.ref), manifestDigest.String())
res, err := d.c.makeRequest(ctx, http.MethodPut, path, nil, bytes.NewReader(body), v2Auth, nil)
if err != nil {
return err
}
defer res.Body.Close()
if res.StatusCode != http.StatusCreated {
logrus.Debugf("Error uploading signature, status %d, %#v", res.StatusCode, res)
return fmt.Errorf("uploading signature to %s in %s: %w", path, d.c.registry, registryHTTPResponseToError(res))
}
}
return nil
}
// CommitWithOptions marks the process of storing the image as successful and asks for the image to be persisted.
// WARNING: This does not have any transactional semantics:
// - Uploaded data MAY be visible to others before CommitWithOptions() is called
// - Uploaded data MAY be removed or MAY remain around if Close() is called without CommitWithOptions() (i.e. rollback is allowed but not guaranteed)
func (d *dockerImageDestination) CommitWithOptions(ctx context.Context, options private.CommitOptions) error {
return nil
}