Remove the attestation media type field. (#565)

This was never actually correct - these are technically "payloadTypes", which are
not actually mediaTypes. Some implementations mistakenly sent incorrect media types, so
it appeared to work. The GCS storage layer rejected correct implementations that sent the
payloadType, because these are not valid mediaTypes.

We never used this field anyway, so let's drop it. I verified that the API correctly ignores
unknown fields, so removing this will not break clients that send it.

Signed-off-by: Dan Lorenc <lorenc.d@gmail.com>

cmd/rekor-cli/app/get.go

@@ -159,7 +159,6 @@ func parseEntry(uuid string, e models.LogEntryAnon) (interface{}, error) {
 
 	if e.Attestation != nil {
 		obj.Attestation = string(e.Attestation.Data)
-		obj.AttestationType = e.Attestation.MediaType
 	}
 
 	return &obj, nil

openapi.yaml

@@ -468,9 +468,7 @@ definitions:
           type: object
           properties:
             data:
-              format: byte
-            mediaType:
-              format: string
+              format: byte       
 
           format: byte
         verification:

pkg/api/entries.go

@@ -94,13 +94,12 @@ func logEntryFromLeaf(ctx context.Context, signer signature.Signer, tc TrillianC
 
 	uuid := hex.EncodeToString(leaf.MerkleLeafHash)
 	if viper.GetBool("enable_attestation_storage") {
-		att, typ, err := storageClient.FetchAttestation(ctx, uuid)
+		att, err := storageClient.FetchAttestation(ctx, uuid)
 		if err != nil {
 			log.Logger.Errorf("error fetching attestation: %s %s", uuid, err)
 		} else {
 			logEntryAnon.Attestation = &models.LogEntryAnonAttestation{
-				Data:      att,
-				MediaType: typ,
+				Data: att,
 			}
 		}
 	}
@@ -210,12 +209,12 @@ func createLogEntry(params entries.CreateLogEntryParams) (models.LogEntry, middl
 	if viper.GetBool("enable_attestation_storage") {
 
 		go func() {
-			typ, attestation := entry.Attestation()
-			if typ == "" {
+			attestation := entry.Attestation()
+			if attestation == nil {
 				log.RequestIDLogger(params.HTTPRequest).Infof("no attestation for %s", uuid)
 				return
 			}
-			if err := storeAttestation(context.Background(), uuid, typ, attestation); err != nil {
+			if err := storeAttestation(context.Background(), uuid, attestation); err != nil {
 				log.RequestIDLogger(params.HTTPRequest).Errorf("error storing attestation: %s", err)
 			}
 		}()

pkg/api/index.go

@@ -96,6 +96,6 @@ func addToIndex(ctx context.Context, key, value string) error {
 	return redisClient.Do(ctx, radix.Cmd(nil, "LPUSH", key, value))
 }
 
-func storeAttestation(ctx context.Context, uuid, attestationType string, attestation []byte) error {
-	return storageClient.StoreAttestation(ctx, uuid, attestationType, attestation)
+func storeAttestation(ctx context.Context, uuid string, attestation []byte) error {
+	return storageClient.StoreAttestation(ctx, uuid, attestation)
 }

pkg/generated/models/log_entry.go

@@ -300,9 +300,6 @@ type LogEntryAnonAttestation struct {
 	// data
 	// Format: byte
 	Data strfmt.Base64 `json:"data,omitempty"`
-
-	// media type
-	MediaType string `json:"mediaType,omitempty"`
 }
 
 // Validate validates this log entry anon attestation

pkg/generated/restapi/embedded_spec.go

@@ -498,9 +498,6 @@ func init() {
             "properties": {
               "data": {
                 "format": "byte"
-              },
-              "mediaType": {
-                "format": "string"
               }
             }
           },
@@ -1982,9 +1979,6 @@ func init() {
           "properties": {
             "data": {
               "format": "byte"
-            },
-            "mediaType": {
-              "format": "string"
             }
           }
         },
@@ -2025,9 +2019,6 @@ func init() {
       "properties": {
         "data": {
           "format": "byte"
-        },
-        "mediaType": {
-          "format": "string"
         }
       }
     },

pkg/storage/storage.go

@@ -31,8 +31,8 @@ import (
 )
 
 type AttestationStorage interface {
-	StoreAttestation(ctx context.Context, key string, attestationType string, attestation []byte) error
-	FetchAttestation(ctx context.Context, key string) ([]byte, string, error)
+	StoreAttestation(ctx context.Context, key string, attestation []byte) error
+	FetchAttestation(ctx context.Context, key string) ([]byte, error)
 }
 
 func NewAttestationStorage() (AttestationStorage, error) {
@@ -53,11 +53,9 @@ type Blob struct {
 	bucket *blob.Bucket
 }
 
-func (b *Blob) StoreAttestation(ctx context.Context, key, attestationType string, attestation []byte) error {
-	log.Logger.Infof("storing attestation of type %s at %s", attestationType, key)
-	w, err := b.bucket.NewWriter(ctx, key, &blob.WriterOptions{
-		ContentType: attestationType,
-	})
+func (b *Blob) StoreAttestation(ctx context.Context, key string, attestation []byte) error {
+	log.Logger.Infof("storing attestation at %s", key)
+	w, err := b.bucket.NewWriter(ctx, key, nil)
 	if err != nil {
 		return err
 	}
@@ -67,23 +65,19 @@ func (b *Blob) StoreAttestation(ctx context.Context, key, attestationType string
 	return w.Close()
 }
 
-func (b *Blob) FetchAttestation(ctx context.Context, key string) ([]byte, string, error) {
+func (b *Blob) FetchAttestation(ctx context.Context, key string) ([]byte, error) {
 	log.Logger.Infof("fetching attestation %s", key)
 	exists, err := b.bucket.Exists(ctx, key)
 	if err != nil {
-		return nil, "", err
+		return nil, err
 	}
 	if !exists {
-		return nil, "", nil
-	}
-	att, err := b.bucket.Attributes(ctx, key)
-	if err != nil {
-		return nil, "", err
+		return nil, nil
 	}
 
 	data, err := b.bucket.ReadAll(ctx, key)
 	if err != nil {
-		return nil, "", err
+		return nil, err
 	}
-	return data, att.ContentType, nil
+	return data, nil
 }

pkg/types/alpine/v0.0.1/entry.go

@@ -300,8 +300,8 @@ func (v V001Entry) validate() error {
 	return nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/entries.go

@@ -35,7 +35,7 @@ type EntryImpl interface {
 	IndexKeys() ([]string, error)                     // the keys that should be added to the external index for this entry
 	Canonicalize(ctx context.Context) ([]byte, error) // marshal the canonical entry to be put into the tlog
 	Unmarshal(e models.ProposedEntry) error           // unmarshal the abstract entry into the specific struct for this versioned type
-	Attestation() (string, []byte)
+	Attestation() []byte
 	CreateFromArtifactProperties(context.Context, ArtifactProperties) (models.ProposedEntry, error)
 }
 

pkg/types/hashedrekord/v0.0.1/entry.go

@@ -182,8 +182,8 @@ func (v *V001Entry) validate() (pki.Signature, pki.PublicKey, error) {
 	return sigObj, keyObj, nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/helm/v0.0.1/entry.go

@@ -299,8 +299,8 @@ func (v V001Entry) validate() error {
 	return nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/intoto/v0.0.1/entry.go

@@ -193,12 +193,12 @@ func (v *V001Entry) validate() error {
 	return nil
 }
 
-func (v *V001Entry) Attestation() (string, []byte) {
+func (v *V001Entry) Attestation() []byte {
 	if len(v.env.Payload) > viper.GetInt("max_attestation_size") {
 		log.Logger.Infof("Skipping attestation storage, size %d is greater than max %d", len(v.env.Payload), viper.GetInt("max_attestation_size"))
-		return "", nil
+		return nil
 	}
-	return v.env.PayloadType, []byte(v.env.Payload)
+	return []byte(v.env.Payload)
 }
 
 type verifier struct {

pkg/types/jar/v0.0.1/entry.go

@@ -290,8 +290,8 @@ func extractPKCS7SignatureFromJAR(inz *zip.Reader) ([]byte, error) {
 	return nil, errors.New("unable to locate signature in JAR file")
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/rekord/v0.0.1/entry.go

@@ -353,8 +353,8 @@ func (v V001Entry) validate() error {
 	return nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/rfc3161/v0.0.1/entry.go

@@ -173,8 +173,8 @@ func (v V001Entry) validate() error {
 	return nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(_ context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/rpm/v0.0.1/entry.go

@@ -321,8 +321,8 @@ func (v V001Entry) validate() error {
 	return nil
 }
 
-func (v V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/test_util.go

@@ -48,8 +48,8 @@ func (u BaseUnmarshalTester) Validate() error {
 	return nil
 }
 
-func (u BaseUnmarshalTester) Attestation() (string, []byte) {
-	return "", nil
+func (u BaseUnmarshalTester) Attestation() []byte {
+	return nil
 }
 
 func (u BaseUnmarshalTester) CreateFromArtifactProperties(_ context.Context, _ ArtifactProperties) (models.ProposedEntry, error) {

pkg/types/tuf/v0.0.1/entry.go

@@ -313,8 +313,8 @@ func (v V001Entry) Validate() error {
 	return nil
 }
 
-func (v *V001Entry) Attestation() (string, []byte) {
-	return "", nil
+func (v *V001Entry) Attestation() []byte {
+	return nil
 }
 
 func (v V001Entry) CreateFromArtifactProperties(ctx context.Context, props types.ArtifactProperties) (models.ProposedEntry, error) {