fix: need to implement MetadataTypeProof support

go.mod

@@ -17,11 +17,13 @@ require (
 	go.sia.tech/jape v0.11.1
 	go.uber.org/fx v1.20.1
 	go.uber.org/zap v1.26.0
+	lukechampine.com/blake3 v1.2.1
 	nhooyr.io/websocket v1.7.1
 )
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/klauspost/cpuid/v2 v2.0.9 // indirect
 	github.com/mr-tron/base58 v1.1.0 // indirect
 	github.com/multiformats/go-base32 v0.0.3 // indirect
 	github.com/multiformats/go-base36 v0.1.0 // indirect

go.sum

@@ -16,6 +16,8 @@ github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/julienschmidt/httprouter v1.3.0 h1:U0609e9tgbseu3rBINet9P48AI/D3oJs4dN7jwJOQ1U=
 github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
+github.com/klauspost/cpuid/v2 v2.0.9 h1:lgaqFMSdTdQYdZ04uHyN2d/eKdOMyi2YLSvlQIBFYa4=
+github.com/klauspost/cpuid/v2 v2.0.9/go.mod h1:FInQzS24/EEf25PyTYn52gqo7WaD8xa0213Md/qVLRg=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
@@ -107,5 +109,7 @@ gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+lukechampine.com/blake3 v1.2.1 h1:YuqqRuaqsGV71BV/nm9xlI0MKUv4QC54jQnBChWbGnI=
+lukechampine.com/blake3 v1.2.1/go.mod h1:0OFRp7fBtAylGVCO40o87sbupkyIGgbpv1+M1k1LM6k=
 nhooyr.io/websocket v1.7.1 h1:W8X03PI0a2fiKb3Srck2gpmWr8UwJqDGndXw8bb93yM=
 nhooyr.io/websocket v1.7.1/go.mod h1:FyTYp9aYEPchTiPpXj2mOOnHJ49S35YStWZCjotwizg=

metadata/media_metadata.go

@@ -1,10 +1,17 @@
 package metadata
 
 import (
+	"bytes"
+	"crypto/ed25519"
 	"errors"
+	"git.lumeweb.com/LumeWeb/libs5-go/encoding"
 	"git.lumeweb.com/LumeWeb/libs5-go/serialize"
 	"git.lumeweb.com/LumeWeb/libs5-go/types"
+	"git.lumeweb.com/LumeWeb/libs5-go/utils"
 	"github.com/vmihailenco/msgpack/v5"
+	"io"
+	"lukechampine.com/blake3"
+	_ "lukechampine.com/blake3"
 )
 
 var (
@@ -23,9 +30,14 @@ type MediaMetadata struct {
 	Details       MediaMetadataDetails
 	Links         *MediaMetadataLinks
 	ExtraMetadata ExtraMetadata
+	provenPubKeys []*encoding.Multihash
 	BaseMetadata
 }
 
+func (m *MediaMetadata) ProvenPubKeys() []*encoding.Multihash {
+	return m.provenPubKeys
+}
+
 func NewMediaMetadata(name string, details MediaMetadataDetails, parents []MetadataParentLink, mediaTypes map[string][]MediaFormat, links *MediaMetadataLinks, extraMetadata ExtraMetadata) *MediaMetadata {
 	return &MediaMetadata{
 		Name:          name,
@@ -61,7 +73,78 @@ func (m *MediaMetadata) DecodeMsgpack(dec *msgpack.Decoder) error {
 }
 
 func (m *MediaMetadata) decodeProof(dec *msgpack.Decoder) error {
-	return errors.New("Not implemented")
+	all, err := io.ReadAll(dec.Buffered())
+	if err != nil {
+		return err
+	}
+
+	proofSectionLength := utils.DecodeEndian(all[0:2])
+
+	bodyBytes := all[2+proofSectionLength:]
+
+	if proofSectionLength == 0 {
+		return nil
+	}
+
+	childDec := msgpack.NewDecoder(bytes.NewReader(all[2 : proofSectionLength+4]))
+
+	b3hash := blake3.Sum256(bodyBytes)
+
+	arrayLen, err := childDec.DecodeArrayLen()
+	if err != nil {
+		return err
+	}
+
+	provenPubKeys := make([]*encoding.Multihash, 0)
+
+	for i := 0; i < arrayLen; i++ {
+		proofData, err := childDec.DecodeSlice()
+		if err != nil {
+			return err
+		}
+
+		for j := 0; j < len(proofData); j++ {
+			var mhashType int
+			var pubkey []byte
+			var signature []byte
+
+			switch j {
+			case 0:
+				sigType := proofData[j].(int)
+				if types.MetadataProofType(sigType) != types.MetadataProofTypeSignature {
+					return errors.New("Invalid proof type")
+				}
+			case 1:
+				mhashType = proofData[j].(int)
+				if types.HashType(mhashType) != types.HashTypeBlake3 {
+					return errors.New("Invalid hash type")
+				}
+
+			case 2:
+				pubkey = proofData[j].([]byte)
+				if types.HashType(mhashType) != types.HashTypeEd25519 {
+					return errors.New("Invalid public key type")
+				}
+
+				if len(pubkey) != 33 {
+					return errors.New("Invalid public key length")
+				}
+
+			case 3:
+				signature = proofData[j].([]byte)
+
+				if valid := ed25519.Verify(pubkey, b3hash[:], signature); !valid {
+					return errors.New("Invalid signature")
+				}
+
+				provenPubKeys = append(provenPubKeys, encoding.NewMultihash(pubkey))
+			}
+		}
+	}
+
+	m.provenPubKeys = provenPubKeys
+
+	return m.decodeMedia(msgpack.NewDecoder(bytes.NewReader(bodyBytes)))
 }
 
 func (m *MediaMetadata) decodeMedia(dec *msgpack.Decoder) error {
@@ -80,11 +163,20 @@ func (m *MediaMetadata) decodeMedia(dec *msgpack.Decoder) error {
 		return err
 	}
 
-	err = dec.Decode(&m.Parents)
+	arrLen, err := dec.DecodeArrayLen()
 	if err != nil {
 		return err
 	}
 
+	parents := make([]MetadataParentLink, arrLen)
+	for i := 0; i < arrLen; i++ {
+		parents[i].SetParent(m)
+		err = dec.Decode(&parents[i])
+		if err != nil {
+			return err
+		}
+	}
+
 	err = dec.Decode(&m.MediaTypes)
 	if err != nil {
 		return err

metadata/parent_link.go

@@ -18,6 +18,11 @@ type MetadataParentLink struct {
 	Type   types.ParentLinkType
 	Role   string
 	Signed bool
+	parent *MediaMetadata
+}
+
+func (m *MetadataParentLink) SetParent(parent *MediaMetadata) {
+	m.parent = parent
 }
 
 func (m *MetadataParentLink) EncodeMsgpack(enc *msgpack.Encoder) error {
@@ -31,6 +36,8 @@ func (m *MetadataParentLink) DecodeMsgpack(dec *msgpack.Decoder) error {
 		return err
 	}
 
+	cid := &encoding.CID{}
+
 	for i := 0; i < mapLen; i++ {
 		key, err := dec.DecodeInt8()
 		if err != nil {
@@ -45,7 +52,7 @@ func (m *MetadataParentLink) DecodeMsgpack(dec *msgpack.Decoder) error {
 		case 0:
 			m.Type = types.ParentLinkType(value.(int))
 		case 1:
-			cid, err := encoding.CIDFromBytes(value.([]byte))
+			cid, err = encoding.CIDFromBytes(value.([]byte))
 			if err != nil {
 				return err
 			}
@@ -60,6 +67,15 @@ func (m *MetadataParentLink) DecodeMsgpack(dec *msgpack.Decoder) error {
 
 	m.Signed = false
 
+	if m.parent != nil {
+		for _, key := range m.parent.ProvenPubKeys() {
+			if cid.Hash.Equals(key) {
+				m.Signed = true
+				break
+			}
+		}
+	}
+
 	return nil
 }
 

types/meta.go

@@ -57,3 +57,15 @@ var MetadataTypeMap = map[string]MetadataType{
 	"Proof":        MetadataTypeProof,
 	"UserIdentity": MetadataTypeUserIdentity,
 }
+
+type MetadataProofType uint8
+
+const (
+	MetadataProofTypeSignature MetadataProofType = 0x01
+	MetadataProofTypeTimestamp MetadataProofType = 0x02
+)
+
+var MetadataProofTypeMap = map[string]MetadataProofType{
+	"Signature": MetadataProofTypeSignature,
+	"Timestamp": MetadataProofTypeTimestamp,
+}