chore: vendor

vendor/github.com/containers/image/docker/docker_image_src.go

@@ -0,0 +1,451 @@
+package docker
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime"
+	"net/http"
+	"net/url"
+	"os"
+	"strconv"
+
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/manifest"
+	"github.com/containers/image/pkg/sysregistriesv2"
+	"github.com/containers/image/types"
+	"github.com/docker/distribution/registry/client"
+	digest "github.com/opencontainers/go-digest"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+type dockerImageSource struct {
+	ref dockerReference
+	c   *dockerClient
+	// State
+	cachedManifest         []byte // nil if not loaded yet
+	cachedManifestMIMEType string // Only valid if cachedManifest != nil
+}
+
+// newImageSource creates a new ImageSource for the specified image reference.
+// The caller must call .Close() on the returned ImageSource.
+func newImageSource(ctx context.Context, sys *types.SystemContext, ref dockerReference) (*dockerImageSource, error) {
+	registry, err := sysregistriesv2.FindRegistry(sys, ref.ref.Name())
+	if err != nil {
+		return nil, errors.Wrapf(err, "error loading registries configuration")
+	}
+	if registry == nil {
+		// No configuration was found for the provided reference, so use the
+		// equivalent of a default configuration.
+		registry = &sysregistriesv2.Registry{
+			Endpoint: sysregistriesv2.Endpoint{
+				Location: ref.ref.String(),
+			},
+			Prefix: ref.ref.String(),
+		}
+	}
+
+	primaryDomain := reference.Domain(ref.ref)
+	// Check all endpoints for the manifest availability. If we find one that does
+	// contain the image, it will be used for all future pull actions.  Always try the
+	// non-mirror original location last; this both transparently handles the case
+	// of no mirrors configured, and ensures we return the error encountered when
+	// acessing the upstream location if all endpoints fail.
+	manifestLoadErr := errors.New("Internal error: newImageSource returned without trying any endpoint")
+	pullSources, err := registry.PullSourcesFromReference(ref.ref)
+	if err != nil {
+		return nil, err
+	}
+	for _, pullSource := range pullSources {
+		logrus.Debugf("Trying to pull %q", pullSource.Reference)
+		dockerRef, err := newReference(pullSource.Reference)
+		if err != nil {
+			return nil, err
+		}
+
+		endpointSys := sys
+		// sys.DockerAuthConfig does not explicitly specify a registry; we must not blindly send the credentials intended for the primary endpoint to mirrors.
+		if endpointSys != nil && endpointSys.DockerAuthConfig != nil && reference.Domain(dockerRef.ref) != primaryDomain {
+			copy := *endpointSys
+			copy.DockerAuthConfig = nil
+			endpointSys = &copy
+		}
+
+		client, err := newDockerClientFromRef(endpointSys, dockerRef, false, "pull")
+		if err != nil {
+			return nil, err
+		}
+		client.tlsClientConfig.InsecureSkipVerify = pullSource.Endpoint.Insecure
+
+		testImageSource := &dockerImageSource{
+			ref: dockerRef,
+			c:   client,
+		}
+
+		manifestLoadErr = testImageSource.ensureManifestIsLoaded(ctx)
+		if manifestLoadErr == nil {
+			return testImageSource, nil
+		}
+	}
+	return nil, manifestLoadErr
+}
+
+// Reference returns the reference used to set up this source, _as specified by the user_
+// (not as the image itself, or its underlying storage, claims).  This can be used e.g. to determine which public keys are trusted for this image.
+func (s *dockerImageSource) Reference() types.ImageReference {
+	return s.ref
+}
+
+// Close removes resources associated with an initialized ImageSource, if any.
+func (s *dockerImageSource) Close() error {
+	return nil
+}
+
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *dockerImageSource) LayerInfosForCopy(ctx context.Context) ([]types.BlobInfo, error) {
+	return nil, nil
+}
+
+// simplifyContentType drops parameters from a HTTP media type (see https://tools.ietf.org/html/rfc7231#section-3.1.1.1)
+// Alternatively, an empty string is returned unchanged, and invalid values are "simplified" to an empty string.
+func simplifyContentType(contentType string) string {
+	if contentType == "" {
+		return contentType
+	}
+	mimeType, _, err := mime.ParseMediaType(contentType)
+	if err != nil {
+		return ""
+	}
+	return mimeType
+}
+
+// GetManifest returns the image's manifest along with its MIME type (which may be empty when it can't be determined but the manifest is available).
+// It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve (when the primary manifest is a manifest list);
+// this never happens if the primary manifest is not a manifest list (e.g. if the source never returns manifest lists).
+func (s *dockerImageSource) GetManifest(ctx context.Context, instanceDigest *digest.Digest) ([]byte, string, error) {
+	if instanceDigest != nil {
+		return s.fetchManifest(ctx, instanceDigest.String())
+	}
+	err := s.ensureManifestIsLoaded(ctx)
+	if err != nil {
+		return nil, "", err
+	}
+	return s.cachedManifest, s.cachedManifestMIMEType, nil
+}
+
+func (s *dockerImageSource) fetchManifest(ctx context.Context, tagOrDigest string) ([]byte, string, error) {
+	path := fmt.Sprintf(manifestPath, reference.Path(s.ref.ref), tagOrDigest)
+	headers := map[string][]string{
+		"Accept": manifest.DefaultRequestedManifestMIMETypes,
+	}
+	res, err := s.c.makeRequest(ctx, "GET", path, headers, nil, v2Auth, nil)
+	if err != nil {
+		return nil, "", err
+	}
+	defer res.Body.Close()
+	if res.StatusCode != http.StatusOK {
+		return nil, "", errors.Wrapf(client.HandleErrorResponse(res), "Error reading manifest %s in %s", tagOrDigest, s.ref.ref.Name())
+	}
+	manblob, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, "", err
+	}
+	return manblob, simplifyContentType(res.Header.Get("Content-Type")), nil
+}
+
+// ensureManifestIsLoaded sets s.cachedManifest and s.cachedManifestMIMEType
+//
+// ImageSource implementations are not required or expected to do any caching,
+// but because our signatures are “attached” to the manifest digest,
+// we need to ensure that the digest of the manifest returned by GetManifest(ctx, nil)
+// and used by GetSignatures(ctx, nil) are consistent, otherwise we would get spurious
+// signature verification failures when pulling while a tag is being updated.
+func (s *dockerImageSource) ensureManifestIsLoaded(ctx context.Context) error {
+	if s.cachedManifest != nil {
+		return nil
+	}
+
+	reference, err := s.ref.tagOrDigest()
+	if err != nil {
+		return err
+	}
+
+	manblob, mt, err := s.fetchManifest(ctx, reference)
+	if err != nil {
+		return err
+	}
+	// We might validate manblob against the Docker-Content-Digest header here to protect against transport errors.
+	s.cachedManifest = manblob
+	s.cachedManifestMIMEType = mt
+	return nil
+}
+
+func (s *dockerImageSource) getExternalBlob(ctx context.Context, urls []string) (io.ReadCloser, int64, error) {
+	var (
+		resp *http.Response
+		err  error
+	)
+	for _, url := range urls {
+		resp, err = s.c.makeRequestToResolvedURL(ctx, "GET", url, nil, nil, -1, noAuth, nil)
+		if err == nil {
+			if resp.StatusCode != http.StatusOK {
+				err = errors.Errorf("error fetching external blob from %q: %d (%s)", url, resp.StatusCode, http.StatusText(resp.StatusCode))
+				logrus.Debug(err)
+				continue
+			}
+			break
+		}
+	}
+	if err != nil {
+		return nil, 0, err
+	}
+	return resp.Body, getBlobSize(resp), nil
+}
+
+func getBlobSize(resp *http.Response) int64 {
+	size, err := strconv.ParseInt(resp.Header.Get("Content-Length"), 10, 64)
+	if err != nil {
+		size = -1
+	}
+	return size
+}
+
+// HasThreadSafeGetBlob indicates whether GetBlob can be executed concurrently.
+func (s *dockerImageSource) HasThreadSafeGetBlob() bool {
+	return true
+}
+
+// GetBlob returns a stream for the specified blob, and the blob’s size (or -1 if unknown).
+// The Digest field in BlobInfo is guaranteed to be provided, Size may be -1 and MediaType may be optionally provided.
+// May update BlobInfoCache, preferably after it knows for certain that a blob truly exists at a specific location.
+func (s *dockerImageSource) GetBlob(ctx context.Context, info types.BlobInfo, cache types.BlobInfoCache) (io.ReadCloser, int64, error) {
+	if len(info.URLs) != 0 {
+		return s.getExternalBlob(ctx, info.URLs)
+	}
+
+	path := fmt.Sprintf(blobsPath, reference.Path(s.ref.ref), info.Digest.String())
+	logrus.Debugf("Downloading %s", path)
+	res, err := s.c.makeRequest(ctx, "GET", path, nil, nil, v2Auth, nil)
+	if err != nil {
+		return nil, 0, err
+	}
+	if res.StatusCode != http.StatusOK {
+		// print url also
+		return nil, 0, errors.Errorf("Invalid status code returned when fetching blob %d (%s)", res.StatusCode, http.StatusText(res.StatusCode))
+	}
+	cache.RecordKnownLocation(s.ref.Transport(), bicTransportScope(s.ref), info.Digest, newBICLocationReference(s.ref))
+	return res.Body, getBlobSize(res), nil
+}
+
+// GetSignatures returns the image's signatures.  It may use a remote (= slow) service.
+// If instanceDigest is not nil, it contains a digest of the specific manifest instance to retrieve signatures for
+// (when the primary manifest is a manifest list); this never happens if the primary manifest is not a manifest list
+// (e.g. if the source never returns manifest lists).
+func (s *dockerImageSource) GetSignatures(ctx context.Context, instanceDigest *digest.Digest) ([][]byte, error) {
+	if err := s.c.detectProperties(ctx); err != nil {
+		return nil, err
+	}
+	switch {
+	case s.c.signatureBase != nil:
+		return s.getSignaturesFromLookaside(ctx, instanceDigest)
+	case s.c.supportsSignatures:
+		return s.getSignaturesFromAPIExtension(ctx, instanceDigest)
+	default:
+		return [][]byte{}, nil
+	}
+}
+
+// manifestDigest returns a digest of the manifest, from instanceDigest if non-nil; or from the supplied reference,
+// or finally, from a fetched manifest.
+func (s *dockerImageSource) manifestDigest(ctx context.Context, instanceDigest *digest.Digest) (digest.Digest, error) {
+	if instanceDigest != nil {
+		return *instanceDigest, nil
+	}
+	if digested, ok := s.ref.ref.(reference.Digested); ok {
+		d := digested.Digest()
+		if d.Algorithm() == digest.Canonical {
+			return d, nil
+		}
+	}
+	if err := s.ensureManifestIsLoaded(ctx); err != nil {
+		return "", err
+	}
+	return manifest.Digest(s.cachedManifest)
+}
+
+// getSignaturesFromLookaside implements GetSignatures() from the lookaside location configured in s.c.signatureBase,
+// which is not nil.
+func (s *dockerImageSource) getSignaturesFromLookaside(ctx context.Context, instanceDigest *digest.Digest) ([][]byte, error) {
+	manifestDigest, err := s.manifestDigest(ctx, instanceDigest)
+	if err != nil {
+		return nil, err
+	}
+
+	// NOTE: Keep this in sync with docs/signature-protocols.md!
+	signatures := [][]byte{}
+	for i := 0; ; i++ {
+		url := signatureStorageURL(s.c.signatureBase, manifestDigest, i)
+		if url == nil {
+			return nil, errors.Errorf("Internal error: signatureStorageURL with non-nil base returned nil")
+		}
+		signature, missing, err := s.getOneSignature(ctx, url)
+		if err != nil {
+			return nil, err
+		}
+		if missing {
+			break
+		}
+		signatures = append(signatures, signature)
+	}
+	return signatures, nil
+}
+
+// getOneSignature downloads one signature from url.
+// If it successfully determines that the signature does not exist, returns with missing set to true and error set to nil.
+// NOTE: Keep this in sync with docs/signature-protocols.md!
+func (s *dockerImageSource) getOneSignature(ctx context.Context, url *url.URL) (signature []byte, missing bool, err error) {
+	switch url.Scheme {
+	case "file":
+		logrus.Debugf("Reading %s", url.Path)
+		sig, err := ioutil.ReadFile(url.Path)
+		if err != nil {
+			if os.IsNotExist(err) {
+				return nil, true, nil
+			}
+			return nil, false, err
+		}
+		return sig, false, nil
+
+	case "http", "https":
+		logrus.Debugf("GET %s", url)
+		req, err := http.NewRequest("GET", url.String(), nil)
+		if err != nil {
+			return nil, false, err
+		}
+		req = req.WithContext(ctx)
+		res, err := s.c.client.Do(req)
+		if err != nil {
+			return nil, false, err
+		}
+		defer res.Body.Close()
+		if res.StatusCode == http.StatusNotFound {
+			return nil, true, nil
+		} else if res.StatusCode != http.StatusOK {
+			return nil, false, errors.Errorf("Error reading signature from %s: status %d (%s)", url.String(), res.StatusCode, http.StatusText(res.StatusCode))
+		}
+		sig, err := ioutil.ReadAll(res.Body)
+		if err != nil {
+			return nil, false, err
+		}
+		return sig, false, nil
+
+	default:
+		return nil, false, errors.Errorf("Unsupported scheme when reading signature from %s", url.String())
+	}
+}
+
+// getSignaturesFromAPIExtension implements GetSignatures() using the X-Registry-Supports-Signatures API extension.
+func (s *dockerImageSource) getSignaturesFromAPIExtension(ctx context.Context, instanceDigest *digest.Digest) ([][]byte, error) {
+	manifestDigest, err := s.manifestDigest(ctx, instanceDigest)
+	if err != nil {
+		return nil, err
+	}
+
+	parsedBody, err := s.c.getExtensionsSignatures(ctx, s.ref, manifestDigest)
+	if err != nil {
+		return nil, err
+	}
+
+	var sigs [][]byte
+	for _, sig := range parsedBody.Signatures {
+		if sig.Version == extensionSignatureSchemaVersion && sig.Type == extensionSignatureTypeAtomic {
+			sigs = append(sigs, sig.Content)
+		}
+	}
+	return sigs, nil
+}
+
+// deleteImage deletes the named image from the registry, if supported.
+func deleteImage(ctx context.Context, sys *types.SystemContext, ref dockerReference) error {
+	// docker/distribution does not document what action should be used for deleting images.
+	//
+	// Current docker/distribution requires "pull" for reading the manifest and "delete" for deleting it.
+	// quay.io requires "push" (an explicit "pull" is unnecessary), does not grant any token (fails parsing the request) if "delete" is included.
+	// OpenShift ignores the action string (both the password and the token is an OpenShift API token identifying a user).
+	//
+	// We have to hard-code a single string, luckily both docker/distribution and quay.io support "*" to mean "everything".
+	c, err := newDockerClientFromRef(sys, ref, true, "*")
+	if err != nil {
+		return err
+	}
+
+	headers := map[string][]string{
+		"Accept": manifest.DefaultRequestedManifestMIMETypes,
+	}
+	refTail, err := ref.tagOrDigest()
+	if err != nil {
+		return err
+	}
+	getPath := fmt.Sprintf(manifestPath, reference.Path(ref.ref), refTail)
+	get, err := c.makeRequest(ctx, "GET", getPath, headers, nil, v2Auth, nil)
+	if err != nil {
+		return err
+	}
+	defer get.Body.Close()
+	manifestBody, err := ioutil.ReadAll(get.Body)
+	if err != nil {
+		return err
+	}
+	switch get.StatusCode {
+	case http.StatusOK:
+	case http.StatusNotFound:
+		return errors.Errorf("Unable to delete %v. Image may not exist or is not stored with a v2 Schema in a v2 registry", ref.ref)
+	default:
+		return errors.Errorf("Failed to delete %v: %s (%v)", ref.ref, manifestBody, get.Status)
+	}
+
+	digest := get.Header.Get("Docker-Content-Digest")
+	deletePath := fmt.Sprintf(manifestPath, reference.Path(ref.ref), digest)
+
+	// When retrieving the digest from a registry >= 2.3 use the following header:
+	//   "Accept": "application/vnd.docker.distribution.manifest.v2+json"
+	delete, err := c.makeRequest(ctx, "DELETE", deletePath, headers, nil, v2Auth, nil)
+	if err != nil {
+		return err
+	}
+	defer delete.Body.Close()
+
+	body, err := ioutil.ReadAll(delete.Body)
+	if err != nil {
+		return err
+	}
+	if delete.StatusCode != http.StatusAccepted {
+		return errors.Errorf("Failed to delete %v: %s (%v)", deletePath, string(body), delete.Status)
+	}
+
+	if c.signatureBase != nil {
+		manifestDigest, err := manifest.Digest(manifestBody)
+		if err != nil {
+			return err
+		}
+
+		for i := 0; ; i++ {
+			url := signatureStorageURL(c.signatureBase, manifestDigest, i)
+			if url == nil {
+				return errors.Errorf("Internal error: signatureStorageURL with non-nil base returned nil")
+			}
+			missing, err := c.deleteOneSignature(url)
+			if err != nil {
+				return err
+			}
+			if missing {
+				break
+			}
+		}
+	}
+
+	return nil
+}