Basic multisig checking for consensus

consensus/consensus_leader.go

@@ -12,6 +12,7 @@ import (
 	consensus_proto "github.com/harmony-one/harmony/api/consensus"
 	"github.com/harmony-one/harmony/api/services/explorer"
 	"github.com/harmony-one/harmony/core/types"
+	bls_cosi "github.com/harmony-one/harmony/crypto/bls"
 	"github.com/harmony-one/harmony/internal/profiler"
 	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/p2p"
@@ -94,7 +95,7 @@ func (consensus *Consensus) startConsensus(newBlock *types.Block) {
 	// Set state to AnnounceDone
 	consensus.state = AnnounceDone
 
-	// Leader sign the multi-sig itself
+	// Leader sign the block hash itself
 	(*consensus.prepareSigs)[consensus.nodeID] = consensus.priKey.SignHash(consensus.blockHash[:])
 
 	host.BroadcastMessageFromLeader(consensus.host, consensus.GetValidatorPeers(), msgToSend, consensus.OfflinePeers)
@@ -144,41 +145,46 @@ func (consensus *Consensus) processPrepareMessage(message consensus_proto.Messag
 
 	// proceed only when the message is not received before
 	_, ok = (*prepareSigs)[validatorID]
-	shouldProcess := !ok
-	if len((*prepareSigs)) >= ((len(consensus.PublicKeys)*2)/3 + 1) {
-		shouldProcess = false
+	if ok {
+		utils.GetLogInstance().Debug("Already received prepare message from the validator", "validatorID", validatorID)
+		return
 	}
 
-	if shouldProcess {
-		var sign bls.Sign
-		err := sign.Deserialize(prepareSig)
-		if err != nil {
-			utils.GetLogInstance().Error("Failed to deserialize bls signature", "validatorID", validatorID)
-		}
-		// TODO: check bls signature
-		(*prepareSigs)[validatorID] = &sign
-		utils.GetLogInstance().Debug("Received new prepare signature", "numReceivedSoFar", len(*prepareSigs), "validatorID", validatorID, "PublicKeys", len(consensus.PublicKeys))
+	if len((*prepareSigs)) >= ((len(consensus.PublicKeys)*2)/3 + 1) {
+		utils.GetLogInstance().Debug("Received additional new prepare message", "validatorID", validatorID)
+		return
+	}
 
-		// Set the bitmap indicate this validate signed.
-		prepareBitmap.SetKey(value.PubKey, true)
+	// Check BLS signature for the multi-sig
+	var sign bls.Sign
+	err = sign.Deserialize(prepareSig)
+	if err != nil {
+		utils.GetLogInstance().Error("Failed to deserialize bls signature", "validatorID", validatorID)
+		return
 	}
 
-	if !shouldProcess {
-		utils.GetLogInstance().Debug("Received additional new commit message", "validatorID", validatorID)
+	if !sign.VerifyHash(value.PubKey, consensus.blockHash[:]) {
+		utils.GetLogInstance().Error("Received invalid BLS signature", "validatorID", validatorID)
 		return
 	}
 
+	(*prepareSigs)[validatorID] = &sign
+	utils.GetLogInstance().Debug("Received new prepare signature", "numReceivedSoFar", len(*prepareSigs), "validatorID", validatorID, "PublicKeys", len(consensus.PublicKeys))
+
+	// Set the bitmap indicate this validate signed.
+	prepareBitmap.SetKey(value.PubKey, true)
+
 	targetState := PreparedDone
 	if len((*prepareSigs)) >= ((len(consensus.PublicKeys)*2)/3+1) && consensus.state < targetState {
-		utils.GetLogInstance().Debug("Enough commitments received with signatures", "num", len(*prepareSigs), "state", consensus.state)
+		utils.GetLogInstance().Debug("Enough prepares received with signatures", "num", len(*prepareSigs), "state", consensus.state)
 
 		// Construct prepared message
 		msgToSend, aggSig := consensus.constructPreparedMessage()
 		consensus.aggregatedPrepareSig = aggSig
 
-		// Leader sign the multi-sig itself
-		// TODO: sign on the prepared multi-sig, rather than the block hash
-		(*consensus.commitSigs)[consensus.nodeID] = consensus.priKey.SignHash(consensus.blockHash[:])
+		// Leader sign the multi-sig and bitmap
+		multiSigAndBitmap := append(aggSig.Serialize(), prepareBitmap.Bitmap...)
+		(*consensus.commitSigs)[consensus.nodeID] = consensus.priKey.SignHash(multiSigAndBitmap)
 
 		// Broadcast prepared message
 		host.BroadcastMessageFromLeader(consensus.host, consensus.GetValidatorPeers(), msgToSend, consensus.OfflinePeers)
@@ -195,14 +201,13 @@ func (consensus *Consensus) processCommitMessage(message consensus_proto.Message
 	validatorID := message.SenderId
 	commitSig := message.Payload
 
-	shouldProcess := true
 	consensus.mutex.Lock()
 	defer consensus.mutex.Unlock()
 
 	// check consensus Id
 	if consensusID != consensus.consensusID {
-		shouldProcess = false
 		utils.GetLogInstance().Warn("Received Commit with wrong consensus Id", "myConsensusId", consensus.consensusID, "theirConsensusId", consensusID, "consensus", consensus)
+		return
 	}
 
 	if !bytes.Equal(blockHash, consensus.blockHash[:]) {
@@ -234,30 +239,34 @@ func (consensus *Consensus) processCommitMessage(message consensus_proto.Message
 
 	// proceed only when the message is not received before
 	_, ok = (*commitSigs)[validatorID]
-	shouldProcess = shouldProcess && !ok
-
+	if ok {
+		utils.GetLogInstance().Debug("Already received commit message from the validator", "validatorID", validatorID)
+		return
+	}
 	if len((*commitSigs)) >= ((len(consensus.PublicKeys)*2)/3 + 1) {
-		shouldProcess = false
+		utils.GetLogInstance().Debug("Received additional new commit message", "validatorID", strconv.Itoa(int(validatorID)))
+		return
 	}
 
-	if shouldProcess {
-		var sign bls.Sign
-		err := sign.Deserialize(commitSig)
-		if err != nil {
-			utils.GetLogInstance().Debug("Failed to deserialize bls signature", "validatorID", validatorID)
-		}
-		// TODO: check bls signature
-		(*commitSigs)[validatorID] = &sign
-		utils.GetLogInstance().Debug("Received new commit message", "numReceivedSoFar", len(*commitSigs), "validatorID", strconv.Itoa(int(validatorID)))
-		// Set the bitmap indicate this validate signed.
-		commitBitmap.SetKey(value.PubKey, true)
+	var sign bls.Sign
+	err = sign.Deserialize(commitSig)
+	if err != nil {
+		utils.GetLogInstance().Debug("Failed to deserialize bls signature", "validatorID", validatorID)
+		return
 	}
 
-	if !shouldProcess {
-		utils.GetLogInstance().Debug("Received additional new commit message", "validatorID", strconv.Itoa(int(validatorID)))
+	// Verify the signature on prepare multi-sig and bitmap is correct
+	aggSig := bls_cosi.AggregateSig(consensus.GetPrepareSigsArray())
+	if !sign.VerifyHash(value.PubKey, append(aggSig.Serialize(), consensus.prepareBitmap.Bitmap...)) {
+		utils.GetLogInstance().Error("Received invalid BLS signature", "validatorID", validatorID)
 		return
 	}
 
+	(*commitSigs)[validatorID] = &sign
+	utils.GetLogInstance().Debug("Received new commit message", "numReceivedSoFar", len(*commitSigs), "validatorID", strconv.Itoa(int(validatorID)))
+	// Set the bitmap indicate this validate signed.
+	commitBitmap.SetKey(value.PubKey, true)
+
 	targetState := CommittedDone
 	if len(*commitSigs) >= ((len(consensus.PublicKeys)*2)/3+1) && consensus.state != targetState {
 		utils.GetLogInstance().Info("Enough commits received!", "num", len(*commitSigs), "state", consensus.state)

consensus/consensus_leader_test.go

@@ -13,6 +13,7 @@ import (
 	protobuf "github.com/golang/protobuf/proto"
 	consensus_proto "github.com/harmony-one/harmony/api/consensus"
 	"github.com/harmony-one/harmony/core/types"
+	bls_cosi "github.com/harmony-one/harmony/crypto/bls"
 	"github.com/harmony-one/harmony/internal/utils"
 	mock_host "github.com/harmony-one/harmony/p2p/host/mock"
 	"github.com/stretchr/testify/assert"
@@ -159,6 +160,10 @@ func TestProcessMessageLeaderCommit(test *testing.T) {
 	consensusLeader.blockHash = blockHash
 	consensusLeader.OnConsensusDone = func(newBlock *types.Block) {}
 	consensusLeader.block, _ = rlp.EncodeToBytes(types.NewBlock(&types.Header{}, nil, nil))
+	(*consensusLeader.prepareSigs)[consensusLeader.nodeID] = consensusLeader.priKey.SignHash(consensusLeader.blockHash[:])
+
+	aggSig := bls_cosi.AggregateSig(consensusLeader.GetPrepareSigsArray())
+	multiSigAndBitmap := append(aggSig.Serialize(), consensusLeader.prepareBitmap.Bitmap...)
 
 	consensusValidators := make([]*Consensus, 3)
 
@@ -169,7 +174,7 @@ func TestProcessMessageLeaderCommit(test *testing.T) {
 	for i := 0; i < 3; i++ {
 		consensusValidators[i] = New(hosts[i], "0", validators, leader)
 		consensusValidators[i].blockHash = blockHash
-		msg := consensusValidators[i].constructCommitMessage()
+		msg := consensusValidators[i].constructCommitMessage(multiSigAndBitmap)
 		consensusLeader.ProcessMessageLeader(msg[1:])
 	}
 

consensus/consensus_validator.go

@@ -3,6 +3,9 @@ package consensus
 import (
 	"bytes"
 
+	"github.com/harmony-one/bls/ffi/go/bls"
+	bls_cosi "github.com/harmony-one/harmony/crypto/bls"
+
 	"github.com/ethereum/go-ethereum/rlp"
 	protobuf "github.com/golang/protobuf/proto"
 	consensus_proto "github.com/harmony-one/harmony/api/consensus"
@@ -152,12 +155,22 @@ func (consensus *Consensus) processPreparedMessage(message consensus_proto.Messa
 		return
 	}
 
-	_ = multiSig
-	_ = bitmap
-	// TODO: verify multi signature
+	deserializedMultiSig := bls.Sign{}
+	err = deserializedMultiSig.Deserialize(multiSig)
+	if err != nil {
+		utils.GetLogInstance().Warn("Failed to deserialize the multi signature", "Error", err, "leader ID", leaderID)
+		return
+	}
+	mask, err := bls_cosi.NewMask(consensus.PublicKeys, nil)
+	mask.SetMask(bitmap)
+	if !deserializedMultiSig.VerifyHash(mask.AggregatePublic, blockHash) || err != nil {
+		utils.GetLogInstance().Warn("Failed to verify the multi signature", "Error", err, "leader ID", leaderID)
+		return
+	}
+	multiSigAndBitmap := append(multiSig, bitmap...)
 
 	// Construct and send the commit message
-	msgToSend := consensus.constructCommitMessage()
+	msgToSend := consensus.constructCommitMessage(multiSigAndBitmap)
 
 	consensus.SendMessage(consensus.leader, msgToSend)
 
@@ -226,11 +239,6 @@ func (consensus *Consensus) processCommittedMessage(message consensus_proto.Mess
 	_ = bitmap
 	// TODO: verify multi signature
 
-	// Construct and send the prepare message
-	msgToSend := consensus.constructPrepareMessage()
-
-	consensus.SendMessage(consensus.leader, msgToSend)
-
 	consensus.state = CommittedDone
 
 	// TODO: the block catch up logic is a temporary workaround for full failure node catchup. Implement the full node catchup logic

consensus/consensus_validator_msg.go

@@ -44,7 +44,7 @@ func (consensus *Consensus) constructPrepareMessage() []byte {
 }
 
 // Construct the commit message to send to leader (assumption the consensus data is already verified)
-func (consensus *Consensus) constructCommitMessage() []byte {
+func (consensus *Consensus) constructCommitMessage(multiSigAndBitmap []byte) []byte {
 	message := consensus_proto.Message{}
 	message.Type = consensus_proto.MessageType_COMMIT
 
@@ -58,8 +58,7 @@ func (consensus *Consensus) constructCommitMessage() []byte {
 	message.SenderId = uint32(consensus.nodeID)
 
 	// 48 byte of bls signature
-	// TODO: sign on the prepared message hash, rather than the block hash
-	sign := consensus.priKey.SignHash(message.BlockHash)
+	sign := consensus.priKey.SignHash(multiSigAndBitmap)
 	if sign != nil {
 		message.Payload = sign.Serialize()
 	}

consensus/consensus_validator_msg_test.go

@@ -36,9 +36,9 @@ func TestConstructCommitMessage(test *testing.T) {
 	}
 	consensus := New(host, "0", []p2p.Peer{leader, validator}, leader)
 	consensus.blockHash = [32]byte{}
-	msg := consensus.constructCommitMessage()
+	msg := consensus.constructCommitMessage([]byte("random string"))
 
-	if len(msg) != 93 {
+	if len(msg) != 143 {
 		test.Errorf("Commit message is not constructed in the correct size: %d", len(msg))
 	}
 }

consensus/consensus_validator_test.go

@@ -104,6 +104,8 @@ func TestProcessMessageValidatorPrepared(test *testing.T) {
 	copy(consensusLeader.blockHash[:], hashBytes[:])
 
 	announceMsg := consensusLeader.constructAnnounceMessage()
+	(*consensusLeader.prepareSigs)[consensusLeader.nodeID] = consensusLeader.priKey.SignHash(consensusLeader.blockHash[:])
+
 	preparedMsg, _ := consensusLeader.constructPreparedMessage()
 
 	if err != nil {