package graph import ( "bytes" "encoding/json" "fmt" "io" "io/ioutil" log "github.com/Sirupsen/logrus" "github.com/docker/docker/engine" "github.com/docker/docker/pkg/tarsum" "github.com/docker/docker/registry" "github.com/docker/docker/runconfig" "github.com/docker/libtrust" ) func (s *TagStore) newManifest(localName, remoteName, tag string) ([]byte, error) { manifest := ®istry.ManifestData{ Name: remoteName, Tag: tag, SchemaVersion: 1, } localRepo, err := s.Get(localName) if err != nil { return nil, err } if localRepo == nil { return nil, fmt.Errorf("Repo does not exist: %s", localName) } // Get the top-most layer id which the tag points to layerId, exists := localRepo[tag] if !exists { return nil, fmt.Errorf("Tag does not exist for %s: %s", localName, tag) } layersSeen := make(map[string]bool) layer, err := s.graph.Get(layerId) if err != nil { return nil, err } manifest.Architecture = layer.Architecture manifest.FSLayers = make([]*registry.FSLayer, 0, 4) manifest.History = make([]*registry.ManifestHistory, 0, 4) var metadata runconfig.Config if layer.Config != nil { metadata = *layer.Config } for ; layer != nil; layer, err = layer.GetParent() { if err != nil { return nil, err } if layersSeen[layer.ID] { break } if layer.Config != nil && metadata.Image != layer.ID { err = runconfig.Merge(&metadata, layer.Config) if err != nil { return nil, err } } checksum, err := layer.GetCheckSum(s.graph.ImageRoot(layer.ID)) if err != nil { return nil, fmt.Errorf("Error getting image checksum: %s", err) } if tarsum.VersionLabelForChecksum(checksum) != tarsum.Version1.String() { archive, err := layer.TarLayer() if err != nil { return nil, err } tarSum, err := tarsum.NewTarSum(archive, true, tarsum.Version1) if err != nil { return nil, err } if _, err := io.Copy(ioutil.Discard, tarSum); err != nil { return nil, err } checksum = tarSum.Sum(nil) // Save checksum value if err := layer.SaveCheckSum(s.graph.ImageRoot(layer.ID), checksum); err != nil { return nil, err } } jsonData, err := layer.RawJson() if err != nil { return nil, fmt.Errorf("Cannot retrieve the path for {%s}: %s", layer.ID, err) } manifest.FSLayers = append(manifest.FSLayers, ®istry.FSLayer{BlobSum: checksum}) layersSeen[layer.ID] = true manifest.History = append(manifest.History, ®istry.ManifestHistory{V1Compatibility: string(jsonData)}) } manifestBytes, err := json.MarshalIndent(manifest, "", " ") if err != nil { return nil, err } return manifestBytes, nil } // loadManifest loads a manifest from a byte array and verifies its content. // The signature must be verified or an error is returned. If the manifest // contains no signatures by a trusted key for the name in the manifest, the // image is not considered verified. The parsed manifest object and a boolean // for whether the manifest is verified is returned. func (s *TagStore) loadManifest(eng *engine.Engine, manifestBytes []byte) (*registry.ManifestData, bool, error) { sig, err := libtrust.ParsePrettySignature(manifestBytes, "signatures") if err != nil { return nil, false, fmt.Errorf("error parsing payload: %s", err) } keys, err := sig.Verify() if err != nil { return nil, false, fmt.Errorf("error verifying payload: %s", err) } payload, err := sig.Payload() if err != nil { return nil, false, fmt.Errorf("error retrieving payload: %s", err) } var manifest registry.ManifestData if err := json.Unmarshal(payload, &manifest); err != nil { return nil, false, fmt.Errorf("error unmarshalling manifest: %s", err) } if manifest.SchemaVersion != 1 { return nil, false, fmt.Errorf("unsupported schema version: %d", manifest.SchemaVersion) } var verified bool for _, key := range keys { job := eng.Job("trust_key_check") b, err := key.MarshalJSON() if err != nil { return nil, false, fmt.Errorf("error marshalling public key: %s", err) } namespace := manifest.Name if namespace[0] != '/' { namespace = "/" + namespace } stdoutBuffer := bytes.NewBuffer(nil) job.Args = append(job.Args, namespace) job.Setenv("PublicKey", string(b)) // Check key has read/write permission (0x03) job.SetenvInt("Permission", 0x03) job.Stdout.Add(stdoutBuffer) if err = job.Run(); err != nil { return nil, false, fmt.Errorf("error running key check: %s", err) } result := engine.Tail(stdoutBuffer, 1) log.Debugf("Key check result: %q", result) if result == "verified" { verified = true } } return &manifest, verified, nil } func checkValidManifest(manifest *registry.ManifestData) error { if len(manifest.FSLayers) != len(manifest.History) { return fmt.Errorf("length of history not equal to number of layers") } if len(manifest.FSLayers) == 0 { return fmt.Errorf("no FSLayers in manifest") } return nil }