arbo implementation improved to remove hint

arbo/verifier.go

@@ -2,6 +2,7 @@ package arbo
 
 import (
 	"github.com/consensys/gnark/frontend"
+	"github.com/consensys/gnark/std/math/cmp"
 	"github.com/vocdoni/gnark-crypto-primitives/poseidon"
 )
 
@@ -50,18 +51,25 @@ func calcRoot(api frontend.API, current frontend.Variable, path, valid, siblings
 	return calcRoot(api, newCurrent, path[:i], valid[:i], siblings[:i])
 }
 
+// validSiblings function creates a binary map with the slots where a valid
+// sibling is located in the siblings list. This function helps to skip
+// unnecessary iterations when walking through the merkle tree.
+func validSiblings(api frontend.API, siblings []frontend.Variable, nsibling frontend.Variable) []frontend.Variable {
+	valid := make([]frontend.Variable, len(siblings))
+	for i := 0; i < len(siblings); i++ {
+		valid[i] = cmp.IsLess(api, frontend.Variable(i), nsibling)
+	}
+	return valid
+}
+
 // CheckProof receives the parameters of a proof of Arbo to recalculate the
 // root with them and compare it with the provided one, verifiying the proof.
 func CheckProof(api frontend.API, key, value, root, nsiblings frontend.Variable, siblings []frontend.Variable) error {
 	// ensure that the number of valid siblings are less or equal to the number
 	// of provided siblings
 	api.AssertIsLessOrEqual(nsiblings, len(siblings))
-	// call to ValidSiblings that creates a map of valid siblings
-	valid, err := api.NewHint(ValidSiblings, len(siblings), nsiblings)
-	if err != nil {
-		return err
-	}
-
+	// get a map with the valid siblings
+	valid := validSiblings(api, siblings, nsiblings)
 	// calculta the path from the provided key to decide which leaf is the
 	// correct one in every level of the tree
 	path := api.ToBinary(key, api.Compiler().FieldBitLen())

arbo/verifier_test.go

@@ -1,13 +1,11 @@
 package arbo
 
 import (
-	"encoding/hex"
 	"math/big"
 	"testing"
 
 	"github.com/consensys/gnark-crypto/ecc"
 	"github.com/consensys/gnark/backend"
-	"github.com/consensys/gnark/constraint/solver"
 	"github.com/consensys/gnark/frontend"
 	"github.com/consensys/gnark/test"
 	qt "github.com/frankban/quicktest"
@@ -41,15 +39,14 @@ func successInputs(t *testing.T, n int) testVerifierCircuit {
 	})
 	c.Assert(err, qt.IsNil)
 
-	key, err := hex.DecodeString("2a4636A5a1138e35F7f93e81FA56d3c970BC6777")
-	c.Assert(err, qt.IsNil)
+	key := util.BigToFF(new(big.Int).SetBytes(util.RandomBytes(20))).Bytes()
 	value := big.NewInt(10)
 
 	err = tree.Add(key, value.Bytes())
 	c.Assert(err, qt.IsNil)
 
 	for i := 1; i < n; i++ {
-		err = tree.Add(util.RandomBytes(20), value.Bytes())
+		err = tree.Add(util.BigToFF(new(big.Int).SetBytes(util.RandomBytes(20))).Bytes(), value.Bytes())
 		c.Assert(err, qt.IsNil)
 	}
 
@@ -65,7 +62,7 @@ func successInputs(t *testing.T, n int) testVerifierCircuit {
 	siblings := [160]frontend.Variable{}
 	for i := 0; i < 160; i++ {
 		if i < len(uSiblings) {
-			siblings[i] = arbo.BytesToBigInt(uSiblings[i])
+			siblings[i] = arbo.BytesLEToBigInt(uSiblings[i])
 		} else {
 			siblings[i] = big.NewInt(0)
 		}
@@ -74,8 +71,8 @@ func successInputs(t *testing.T, n int) testVerifierCircuit {
 	root, err := tree.Root()
 	c.Assert(err, qt.IsNil)
 	return testVerifierCircuit{
-		Root:      arbo.BytesToBigInt(root),
-		Key:       arbo.BytesToBigInt(key),
+		Root:      arbo.BytesLEToBigInt(root),
+		Key:       arbo.BytesLEToBigInt(key),
 		Value:     value,
 		Siblings:  siblings,
 		NSiblings: new(big.Int).SetInt64(int64(len(uSiblings))),
@@ -86,5 +83,5 @@ func TestVerifier(t *testing.T) {
 	assert := test.NewAssert(t)
 
 	inputs := successInputs(t, 10)
-	assert.SolvingSucceeded(&testVerifierCircuit{}, &inputs, test.WithCurves(ecc.BN254), test.WithBackends(backend.GROTH16), test.WithSolverOpts(solver.WithHints(ValidSiblings)))
+	assert.SolvingSucceeded(&testVerifierCircuit{}, &inputs, test.WithCurves(ecc.BN254), test.WithBackends(backend.GROTH16))
 }

go.mod

@@ -1,53 +1,54 @@
 module github.com/vocdoni/gnark-crypto-primitives
 
-go 1.22
+go 1.23.0
 
-toolchain go1.22.4
+toolchain go1.23.2
 
 require (
 	github.com/consensys/gnark v0.11.0
 	github.com/consensys/gnark-crypto v0.14.0
 	github.com/frankban/quicktest v1.14.6
 	github.com/iden3/go-iden3-crypto v0.0.17
-	go.vocdoni.io/dvote v1.10.1
+	go.vocdoni.io/dvote v1.10.2-0.20241024102542-c1ce6d744bc5
 )
 
 require (
 	github.com/DataDog/zstd v1.5.2 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bits-and-blooms/bitset v1.14.3 // indirect
 	github.com/blang/semver/v4 v4.0.0 // indirect
-	github.com/cespare/xxhash/v2 v2.2.0 // indirect
-	github.com/cockroachdb/errors v1.9.1 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/cockroachdb/errors v1.11.3 // indirect
+	github.com/cockroachdb/fifo v0.0.0-20240606204812-0bbfbd93a7ce // indirect
 	github.com/cockroachdb/logtags v0.0.0-20230118201751-21c54148d20b // indirect
-	github.com/cockroachdb/pebble v0.0.0-20230928194634-aa077af62593 // indirect
-	github.com/cockroachdb/redact v1.1.3 // indirect
+	github.com/cockroachdb/pebble v1.1.2 // indirect
+	github.com/cockroachdb/redact v1.1.5 // indirect
 	github.com/cockroachdb/tokenbucket v0.0.0-20230807174530-cc333fc44b06 // indirect
 	github.com/consensys/bavard v0.1.22 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/fxamacker/cbor/v2 v2.7.0 // indirect
-	github.com/getsentry/sentry-go v0.18.0 // indirect
+	github.com/getsentry/sentry-go v0.27.0 // indirect
 	github.com/glendc/go-external-ip v0.1.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/golang/snappy v0.0.5-0.20220116011046-fa5810519dcb // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/google/pprof v0.0.0-20241101162523-b92577c0c142 // indirect
 	github.com/ingonyama-zk/icicle v1.1.0 // indirect
 	github.com/ingonyama-zk/iciclegnark v0.1.0 // indirect
-	github.com/klauspost/compress v1.17.2 // indirect
+	github.com/klauspost/compress v1.17.9 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
-	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/mmcloughlin/addchain v0.4.0 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
-	github.com/prometheus/client_golang v1.17.0 // indirect
-	github.com/prometheus/client_model v0.5.0 // indirect
-	github.com/prometheus/common v0.44.0 // indirect
-	github.com/prometheus/procfs v0.12.0 // indirect
+	github.com/prometheus/client_golang v1.19.1 // indirect
+	github.com/prometheus/client_model v0.6.1 // indirect
+	github.com/prometheus/common v0.55.0 // indirect
+	github.com/prometheus/procfs v0.15.1 // indirect
 	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	github.com/ronanh/intcomp v1.1.0 // indirect
 	github.com/rs/zerolog v1.33.0 // indirect
@@ -58,7 +59,8 @@ require (
 	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/sys v0.26.0 // indirect
 	golang.org/x/text v0.19.0 // indirect
-	google.golang.org/protobuf v1.31.0 // indirect
+	google.golang.org/protobuf v1.34.2 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
+	lukechampine.com/blake3 v1.3.0 // indirect
 	rsc.io/tmplfunc v0.0.3 // indirect
 )