implement Signer interface for bls12381

Author: freddiecoleman

asserter/construction.go

@@ -215,7 +215,7 @@ func CurveType(
 	curve types.CurveType,
 ) error {
 	switch curve {
-	case types.Secp256k1, types.Secp256r1, types.Edwards25519, types.Tweedle, types.Pallas:
+	case types.Secp256k1, types.Secp256r1, types.Edwards25519, types.Tweedle, types.Pallas, types.Bls12381:
 		return nil
 	default:
 		return fmt.Errorf("%w: %s", ErrCurveTypeNotSupported, curve)
@@ -304,7 +304,7 @@ func SignatureType(
 	signature types.SignatureType,
 ) error {
 	switch signature {
-	case types.Ecdsa, types.EcdsaRecovery, types.Ed25519, types.Schnorr1, types.SchnorrPoseidon:
+	case types.Ecdsa, types.EcdsaRecovery, types.Ed25519, types.Schnorr1, types.SchnorrPoseidon, types.BlsG2Element:
 		return nil
 	default:
 		return fmt.Errorf("%w: %s", ErrSignatureTypeNotSupported, signature)

keys/errors.go

@@ -39,6 +39,9 @@ var (
 	ErrKeyGenPallasFailed = errors.New(
 		"keygen: error generating key pair for pallas curve type",
 	)
+	ErrKeyGenBls12381Failed = errors.New(
+		"keygen: error generating key pair for bls12381 curve type",
+	)
 	ErrCurveTypeNotSupported = errors.New("not a supported CurveType")
 
 	ErrSignUnsupportedPayloadSignatureType = errors.New(

keys/keys.go

@@ -24,6 +24,7 @@ import (
 	"math/big"
 
 	"github.com/btcsuite/btcd/btcec"
+	"github.com/coinbase/kryptology/pkg/signatures/bls/bls_sig"
 	"github.com/coinbase/kryptology/pkg/signatures/schnorr/mina"
 
 	"github.com/coinbase/rosetta-sdk-go/asserter"
@@ -210,6 +211,22 @@ func GenerateKeypair(curve types.CurveType) (*KeyPair, error) {
 			CurveType: curve,
 		}
 
+		keyPair = &KeyPair{
+			PublicKey:  pubKey,
+			PrivateKey: rawPrivKeyBytes,
+		}
+	case types.Bls12381:
+		rawPubKey, rawPrivKey, err := bls_sig.NewSigBasic().Keygen()
+		rawPubKeyBytes, _ := rawPubKey.MarshalBinary()
+		rawPrivKeyBytes, _ := rawPrivKey.MarshalBinary()
+		if err != nil {
+			return nil, fmt.Errorf("%w: %v", ErrKeyGenBls12381Failed, err)
+		}
+		pubKey := &types.PublicKey{
+			Bytes:     rawPubKeyBytes,
+			CurveType: curve,
+		}
+
 		keyPair = &KeyPair{
 			PublicKey:  pubKey,
 			PrivateKey: rawPrivKeyBytes,
@@ -252,6 +269,8 @@ func (k *KeyPair) Signer() (Signer, error) {
 		return &SignerSecp256r1{k}, nil
 	case types.Pallas:
 		return &SignerPallas{k}, nil
+	case types.Bls12381:
+		return &SignerBls12381{k}, nil
 	default:
 		return nil, fmt.Errorf("%w: %s", ErrCurveTypeNotSupported, k.PublicKey.CurveType)
 	}

keys/signer_bls12381.go

@@ -0,0 +1,121 @@
+// Copyright 2022 Coinbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package keys
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/coinbase/kryptology/pkg/signatures/bls/bls_sig"
+	"github.com/coinbase/rosetta-sdk-go/asserter"
+	"github.com/coinbase/rosetta-sdk-go/types"
+)
+
+var ErrBlsTransactionValidationErr = errors.New("transaction with bls validation failed")
+
+type SignerBls12381 struct {
+	KeyPair *KeyPair
+}
+
+func (s *SignerBls12381) PublicKey() *types.PublicKey {
+	return s.KeyPair.PublicKey
+}
+
+// Sign transaction payloads using a KeyPair
+func (s *SignerBls12381) Sign(
+	payload *types.SigningPayload,
+	sigType types.SignatureType,
+) (*types.Signature, error) {
+	err := s.KeyPair.IsValid()
+	if err != nil {
+		return nil, err
+	}
+
+	if !(payload.SignatureType == types.BlsG2Element || payload.SignatureType == "") {
+		return nil, fmt.Errorf(
+			"%w: expected %v but got %v",
+			ErrSignUnsupportedPayloadSignatureType,
+			types.BlsG2Element,
+			payload.SignatureType,
+		)
+	}
+
+	if sigType != types.BlsG2Element {
+		return nil, fmt.Errorf(
+			"%w: expected %v but got %v",
+			ErrSignUnsupportedSignatureType,
+			types.BlsG2Element,
+			sigType,
+		)
+	}
+
+	// Generate private key bytes
+	privKeyBytes := s.KeyPair.PrivateKey
+	privKey := &bls_sig.SecretKey{}
+	_ = privKey.UnmarshalBinary(privKeyBytes)
+
+	bls := bls_sig.NewSigBasic()
+	sig, err := bls.Sign(privKey, payload.Bytes)
+	if err != nil {
+		return nil, err
+	}
+	sigBytes, _ := sig.MarshalBinary()
+
+	return &types.Signature{
+		SigningPayload: payload,
+		PublicKey:      s.KeyPair.PublicKey,
+		SignatureType:  payload.SignatureType,
+		Bytes:          sigBytes,
+	}, nil
+}
+
+// Verify verifies a Signature, by checking the validity of a Signature,
+// the SigningPayload, and the PublicKey of the Signature.
+func (s *SignerBls12381) Verify(signature *types.Signature) error {
+	if signature.SignatureType != types.BlsG2Element {
+		return fmt.Errorf(
+			"%w: expected %v but got %v",
+			ErrVerifyUnsupportedPayloadSignatureType,
+			types.BlsG2Element,
+			signature.SignatureType,
+		)
+	}
+
+	pubKeyBytes := signature.PublicKey.Bytes
+	pubKey := &bls_sig.PublicKey{}
+	_ = pubKey.UnmarshalBinary(pubKeyBytes)
+
+	sigBytes := signature.Bytes
+	sig := &bls_sig.Signature{}
+	_ = sig.UnmarshalBinary(sigBytes)
+
+	err := asserter.Signatures([]*types.Signature{signature})
+	if err != nil {
+		return fmt.Errorf("%w: %s", ErrVerifyFailed, err)
+	}
+
+	bls := bls_sig.NewSigBasic()
+	result, err := bls.Verify(pubKey, signature.SigningPayload.Bytes, sig)
+
+	if err != nil {
+		return err
+	}
+
+	if !result {
+		return fmt.Errorf("%w: %s", ErrVerifyFailed, "Verify failed")
+	}
+
+	return nil
+}

keys/signer_bls12381_test.go

@@ -0,0 +1,113 @@
+// Copyright 2022 Coinbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package keys
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/coinbase/rosetta-sdk-go/types"
+)
+
+var signerBls12381 Signer
+
+func init() {
+	bls12381Keypair, _ := GenerateKeypair(types.Bls12381)
+	signerBls12381, _ = bls12381Keypair.Signer()
+
+	unsignedTxStr := "a7ca4bce10200d073ef10c46e9d27c3b4e31263d4c07fbec447650fcc1b286" +
+		"300e8ecf25c0560f9cb5aa673247fb6a6f95fb73164d1bf5d41288f57ea40517d9da86c44a289ed" +
+		"2b6f9d3bf9a750ee96dbf905073f8ae56c80100ef47f5585acf70baff8c72c3b8a833181fb3edf4" +
+		"328fccd5bb71183532bff220ba46c268991a3ff07eb358e8255a65c30a2dce0e5fbb"
+	txnBytes = []byte(unsignedTxStr)
+}
+
+func TestSignBls12381(t *testing.T) {
+	type payloadTest struct {
+		payload *types.SigningPayload
+		err     bool
+		errMsg  error
+	}
+
+	var payloadTests = []payloadTest{
+		{mockPayload(txnBytes, types.BlsG2Element), false, nil},
+		{mockPayload(txnBytes, ""), false, nil},
+		{mockPayload(txnBytes, types.Ecdsa), true, ErrSignUnsupportedPayloadSignatureType},
+		{
+			mockPayload(txnBytes, types.EcdsaRecovery),
+			true,
+			ErrSignUnsupportedPayloadSignatureType,
+		},
+	}
+	for _, test := range payloadTests {
+		signature, err := signerBls12381.Sign(test.payload, types.BlsG2Element)
+
+		if !test.err {
+			assert.NoError(t, err)
+			assert.Len(t, signature.Bytes, 96)
+			assert.Equal(t, signerBls12381.PublicKey(), signature.PublicKey)
+		} else {
+			assert.Contains(t, err.Error(), test.errMsg.Error())
+		}
+	}
+}
+
+func TestVerifyBls(t *testing.T) {
+	type signatureTest struct {
+		signature *types.Signature
+		errMsg    error
+	}
+
+	payload := mockPayload(txnBytes, types.BlsG2Element)
+	testSignature, err := signerBls12381.Sign(payload, types.BlsG2Element)
+	assert.NoError(t, err)
+
+	simpleBytes := make([]byte, 32)
+	copy(simpleBytes, "hello")
+
+	var signatureTests = []signatureTest{
+		{mockSignature(
+			types.Ecdsa,
+			signerBls12381.PublicKey(),
+			txnBytes,
+			simpleBytes), ErrVerifyUnsupportedPayloadSignatureType},
+		{mockSignature(
+			types.EcdsaRecovery,
+			signerBls12381.PublicKey(),
+			txnBytes,
+			simpleBytes), ErrVerifyUnsupportedPayloadSignatureType},
+		{mockSignature(
+			types.BlsG2Element,
+			signerBls12381.PublicKey(),
+			simpleBytes,
+			testSignature.Bytes), ErrVerifyFailed},
+	}
+
+	for _, test := range signatureTests {
+		err := signerBls12381.Verify(test.signature)
+		assert.Contains(t, err.Error(), test.errMsg.Error())
+	}
+
+	// happy path
+	goodSignature := mockSignature(
+		types.BlsG2Element,
+		signerBls12381.PublicKey(),
+		txnBytes,
+		testSignature.Bytes,
+	)
+
+	assert.Equal(t, nil, signerBls12381.Verify(goodSignature))
+}

types/curve_type.go

@@ -27,6 +27,7 @@ type CurveType string
 
 // List of CurveType
 const (
+	Bls12381     CurveType = "bls12381"
 	Secp256k1    CurveType = "secp256k1"
 	Secp256r1    CurveType = "secp256r1"
 	Edwards25519 CurveType = "edwards25519"

types/signature_type.go

@@ -29,6 +29,7 @@ type SignatureType string
 
 // List of SignatureType
 const (
+	BlsG2Element    SignatureType = "bls12381_g2_element"
 	Ecdsa           SignatureType = "ecdsa"
 	EcdsaRecovery   SignatureType = "ecdsa_recovery"
 	Ed25519         SignatureType = "ed25519"