Leader verifies validator's signatures and collect responses by node id

consensus/consensus.go

@@ -21,8 +21,8 @@ type Consensus struct {
 	commitments map[uint16]kyber.Point
 	// Commits collected from validators.
 	bitmap *crypto.Mask
-	// Signatures collected from validators
-	responses map[string]string
+	// Responses collected from validators
+	responses map[uint16]kyber.Scalar
 	// map of nodeId to validator Peer object
 	validators map[uint16]p2p.Peer
 	// Leader
@@ -89,7 +89,7 @@ func NewConsensus(ip, port, ShardID string, peers []p2p.Peer, leader p2p.Peer) *
 
 	consensus.commitments = make(map[uint16]kyber.Point)
 	consensus.validators = make(map[uint16]p2p.Peer)
-	consensus.responses = make(map[string]string)
+	consensus.responses = make(map[uint16]kyber.Scalar)
 
 	consensus.leader = leader
 	for _, peer := range peers {
@@ -160,7 +160,7 @@ func (consensus *Consensus) getValidatorPeers() []p2p.Peer {
 func (consensus *Consensus) ResetState() {
 	consensus.state = FINISHED
 	consensus.commitments = make(map[uint16]kyber.Point)
-	consensus.responses = make(map[string]string)
+	consensus.responses = make(map[uint16]kyber.Scalar)
 	consensus.secret = nil
 }
 

consensus/consensus_leader.go

@@ -271,7 +271,7 @@ func (consensus *Consensus) processResponseMessage(payload []byte) {
 	offset += 32
 
 	// 2 byte validator id
-	validatorId := string(payload[offset : offset+2])
+	validatorId := binary.BigEndian.Uint16(payload[offset : offset+2])
 	offset += 2
 
 	// 32 byte response
@@ -283,12 +283,6 @@ func (consensus *Consensus) processResponseMessage(payload []byte) {
 	offset += 64
 	//#### END: Read payload data
 
-	// TODO: make use of the data. This is just to avoid the unused variable warning
-	_ = consensusId
-	_ = blockHash
-	_ = response
-	_ = signature
-
 	shouldProcess := true
 	consensus.mutex.Lock()
 	// check consensus Id
@@ -302,12 +296,24 @@ func (consensus *Consensus) processResponseMessage(payload []byte) {
 		return
 	}
 
+	// Verify signature
+	value, ok := consensus.validators[validatorId]
+	if !ok {
+		consensus.Log.Warn("Received message from unrecognized validator", "validatorId", validatorId, "consensus", consensus)
+		return
+	}
+	if schnorr.Verify(crypto.Ed25519Curve, value.PubKey, payload[:offset-64], signature) != nil {
+		consensus.Log.Warn("Received message with invalid signature", "validatorKey", consensus.leader.PubKey, "consensus", consensus)
+		return
+	}
+
 	// proceed only when the message is not received before
-	_, ok := consensus.responses[validatorId]
+	_, ok = consensus.responses[validatorId]
 	shouldProcess = shouldProcess && !ok
 	if shouldProcess {
-		consensus.responses[validatorId] = validatorId
-		//consensus.Log.Debug("Number of responses received", "consensusId", consensus.consensusId, "count", len(consensus.responses))
+		scalar := crypto.Ed25519Curve.Scalar()
+		scalar.UnmarshalBinary(response)
+		consensus.responses[validatorId] = scalar
 	}
 	consensus.mutex.Unlock()