got merkle proof traversal working

field/field.go

@@ -1,6 +1,7 @@
 package field
 
 import (
+	"fmt"
 	"math/big"
 
 	"github.com/consensys/gnark-crypto/ecc"
@@ -36,3 +37,10 @@ var r EmulatedField
 func EmulatedFieldModulus() *big.Int {
 	return r.Modulus()
 }
+
+func PrintHash(f frontend.API, h Hash) {
+	for i := 0; i < 4; i++ {
+		fmt.Println("Hash Limb", i)
+		f.Println(h[i])
+	}
+}

go.mod

@@ -30,4 +30,4 @@ require (
 
 // For now, use a forked version of gnark so that the emaulated fields are
 // mod'ed when printed.  See here:  https://github.com/kevjue/gnark/commit/0b216679a380b4b8d29f10dd96f34e8a5702463e
-replace github.com/consensys/gnark v0.7.2-0.20220921094618-a121a3074ee8 => github.com/kevjue/gnark v0.7.2-0.20221031212238-0b216679a380
+replace github.com/consensys/gnark v0.7.2-0.20220921094618-a121a3074ee8 => github.com/kevjue/gnark v0.7.2-0.20221109003544-edd49e7202a7

go.sum

@@ -16,8 +16,8 @@ github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
 github.com/google/pprof v0.0.0-20220729232143-a41b82acbcb1 h1:8pyqKJvrJqUYaKS851Ule26pwWvey6IDMiczaBLDKLQ=
 github.com/google/pprof v0.0.0-20220729232143-a41b82acbcb1/go.mod h1:gSuNB+gJaOiQKLEZ+q+PK9Mq3SOzhRcw2GsGS/FhYDk=
 github.com/google/subcommands v1.2.0/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
-github.com/kevjue/gnark v0.7.2-0.20221031212238-0b216679a380 h1:AaxoOsAa/6HME7IIZ8XF0RsFNaDjy4WhRX7iK290YqM=
-github.com/kevjue/gnark v0.7.2-0.20221031212238-0b216679a380/go.mod h1:iN7/IRE6Eu2QKnTJEsoS48suBV0O5XrM+Nzo1ipp6Zw=
+github.com/kevjue/gnark v0.7.2-0.20221109003544-edd49e7202a7 h1:pU9438pFjuTjtDA4iV/oOPcdnzL7KelKXp4aHuqn2o4=
+github.com/kevjue/gnark v0.7.2-0.20221109003544-edd49e7202a7/go.mod h1:iN7/IRE6Eu2QKnTJEsoS48suBV0O5XrM+Nzo1ipp6Zw=
 github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=

plonky2_verifier/deserialize.go

@@ -59,19 +59,18 @@ type MerkleProofRaw struct {
 }
 
 func (m *MerkleProofRaw) UnmarshalJSON(data []byte) error {
-	var siblingDict map[string]interface{}
-	if err := json.Unmarshal(data, &siblingDict); err != nil {
+	type SiblingObject struct {
+		Siblings []map[string][]uint64 // "siblings"
+	}
+
+	var siblings SiblingObject
+	if err := json.Unmarshal(data, &siblings); err != nil {
 		panic(err)
 	}
 
-	siblings := siblingDict["siblings"].([]interface{})
-	m.hash = make([][]uint64, len(siblings))
-	for siblingIdx, sibling := range siblings {
-		siblingHash := sibling.(map[string]interface{})["elements"].([]interface{})
-		m.hash[siblingIdx] = make([]uint64, 4)
-		for siblingElementIdx, siblingElement := range siblingHash {
-			m.hash[siblingIdx][siblingElementIdx] = uint64(siblingElement.(float64))
-		}
+	m.hash = make([][]uint64, len(siblings.Siblings))
+	for siblingIdx, sibling := range siblings.Siblings {
+		m.hash[siblingIdx] = sibling["elements"]
 	}
 
 	return nil

plonky2_verifier/fri.go

@@ -100,30 +100,37 @@ func (f *FriChip) hashOrNoop(data []F) Hash {
 
 func (f *FriChip) verifyMerkleProofToCapWithCapIndex(leafData []F, leafIndexBits []frontend.Variable, capIndex F, merkleCap MerkleCap, proof *MerkleProof) {
 	currentDigest := f.hashOrNoop(leafData)
-
-	if len(leafIndexBits) != len(proof.Siblings) {
-		panic("len(leafIndexBits) != len(proof.Siblings)")
-	}
-
 	fourZeros := [4]F{f.qe.ZERO_F, f.qe.ZERO_F, f.qe.ZERO_F, f.qe.ZERO_F}
-	for i, bit := range leafIndexBits {
-		sibling := proof.Siblings[i]
+	field.PrintHash(f.field, currentDigest)
+	for i, sibling := range proof.Siblings {
+		bit := leafIndexBits[i]
 
 		var leftSiblingState poseidon.PoseidonState
 		copy(leftSiblingState[0:4], sibling[0:4])
 		copy(leftSiblingState[4:8], currentDigest[0:4])
 		copy(leftSiblingState[8:12], fourZeros[0:4])
+
 		leftHash := f.poseidonChip.Poseidon(leftSiblingState)
-		leftHashCompress := leftHash[0:4]
+		var leftHashCompress Hash
+		leftHashCompress[0] = leftHash[0]
+		leftHashCompress[1] = leftHash[1]
+		leftHashCompress[2] = leftHash[2]
+		leftHashCompress[3] = leftHash[3]
 
 		var rightSiblingState poseidon.PoseidonState
 		copy(rightSiblingState[0:4], currentDigest[0:4])
 		copy(rightSiblingState[4:8], sibling[0:4])
 		copy(rightSiblingState[8:12], fourZeros[0:4])
-		rightHash := f.poseidonChip.Poseidon(rightSiblingState)
-		rightHashCompress := rightHash[0:4]
 
-		currentDigest = f.api.Select(bit, leftHashCompress, rightHashCompress).(Hash)
+		rightHash := f.poseidonChip.Poseidon(rightSiblingState)
+		var rightHashCompress Hash
+		rightHashCompress[0] = rightHash[0]
+		rightHashCompress[1] = rightHash[1]
+		rightHashCompress[2] = rightHash[2]
+		rightHashCompress[3] = rightHash[3]
+
+		currentDigest = SelectHash(f.field, bit, leftHashCompress, rightHashCompress)
+		field.PrintHash(f.field, currentDigest)
 	}
 }
 

plonky2_verifier/utils.go

@@ -4,6 +4,8 @@ import (
 	"fmt"
 	. "gnark-ed25519/field"
 	"math/bits"
+
+	"github.com/consensys/gnark/frontend"
 )
 
 func reduceWithPowers(qe *QuadraticExtensionAPI, terms []QuadraticExtension, scalar QuadraticExtension) QuadraticExtension {
@@ -30,3 +32,12 @@ func log2Strict(n uint) int {
 	}
 	return res
 }
+
+func SelectHash(fieldAPI frontend.API, bit frontend.Variable, leftHash, rightHash Hash) Hash {
+	var returnHash Hash
+	for i := 0; i < 4; i++ {
+		returnHash[i] = fieldAPI.Select(bit, leftHash[i], rightHash[i]).(F)
+	}
+
+	return returnHash
+}