Add length limit for sigchain bit shift

Signed-off-by: Yilun <[email protected]>

chain/blockvalidator.go

@@ -259,7 +259,11 @@ func GetNextBlockSigner(height uint32, timestamp int64) ([]byte, []byte, pb.Winn
 
 		switch winnerType {
 		case pb.WinnerType_TXN_SIGNER:
-			whash, _ := common.Uint256ParseFromBytes(header.UnsignedHeader.WinnerHash)
+			whash, err := common.Uint256ParseFromBytes(header.UnsignedHeader.WinnerHash)
+			if err != nil {
+				return nil, nil, 0, err
+			}
+
 			txn, err := DefaultLedger.Store.GetTransaction(whash)
 			if err != nil {
 				return nil, nil, 0, err
@@ -277,7 +281,18 @@ func GetNextBlockSigner(height uint32, timestamp int64) ([]byte, []byte, pb.Winn
 			sigChainTxn := payload.(*pb.SigChainTxn)
 			sigChain := &pb.SigChain{}
 			proto.Unmarshal(sigChainTxn.SigChain, sigChain)
-			publicKey, chordID, err = sigChain.GetMiner()
+
+			blockHash, err := common.Uint256ParseFromBytes(sigChain.BlockHash)
+			if err != nil {
+				return nil, nil, 0, err
+			}
+
+			height, err := DefaultLedger.Store.GetHeightByBlockHash(blockHash)
+			if err != nil {
+				return nil, nil, 0, err
+			}
+
+			publicKey, chordID, err = sigChain.GetMiner(height)
 			if err != nil {
 				return nil, nil, 0, err
 			}

cmd/nknd/nknd.go

@@ -46,7 +46,7 @@ import (
 )
 
 const (
-	NetVersionNum = 20 // This is temporary and will be removed soon after mainnet is stabilized
+	NetVersionNum = 21 // This is temporary and will be removed soon after mainnet is stabilized
 )
 
 var (

config/config.go

@@ -161,6 +161,10 @@ var (
 		heights: []uint32{1200000, 0},
 		values:  []bool{false, true},
 	}
+	SigChainBitShiftMaxLength = HeightDependentInt32{
+		heights: []uint32{2543000, 0},
+		values:  []int32{14, 0},
+	}
 )
 
 var (

pb/sigchain.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/nknorg/nkn/v2/common"
 	"github.com/nknorg/nkn/v2/common/serialization"
+	"github.com/nknorg/nkn/v2/config"
 )
 
 const (
@@ -204,7 +205,7 @@ func (sc *SigChain) GetSignerIndex(pubkey []byte) (int, error) {
 	return idx, err
 }
 
-func (sc *SigChain) GetMiner() ([]byte, []byte, error) {
+func (sc *SigChain) GetMiner(height uint32) ([]byte, []byte, error) {
 	if !sc.IsComplete() {
 		return nil, nil, errors.New("sigchain is not complete")
 	}
@@ -233,7 +234,7 @@ func (sc *SigChain) GetMiner() ([]byte, []byte, error) {
 		return nil, nil, errors.New("no mining element")
 	}
 
-	sigHash, err := sc.SignatureHash()
+	sigHash, err := sc.SignatureHash(height)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -281,12 +282,12 @@ func (sc *SigChain) LastRelayHash() ([]byte, error) {
 	return prevHash, nil
 }
 
-func (sc *SigChain) SignatureHash() ([]byte, error) {
+func (sc *SigChain) SignatureHash(height uint32) ([]byte, error) {
 	lastRelayHash, err := sc.LastRelayHash()
 	if err != nil {
 		return nil, err
 	}
-	sigHash := ComputeSignatureHash(lastRelayHash, sc.Length())
+	sigHash := ComputeSignatureHash(lastRelayHash, sc.Length(), height)
 	return sigHash, nil
 }
 
@@ -307,9 +308,13 @@ func (sc *SigChain) ToMap() map[string]interface{} {
 	}
 }
 
-func ComputeSignatureHash(lastRelayHash []byte, sigChainLen int) []byte {
+func ComputeSignatureHash(lastRelayHash []byte, sigChainLen int, height uint32) []byte {
 	h := sha256.Sum256(lastRelayHash)
 	sigHash := h[:]
+	maxSigChainLen := int(config.SigChainBitShiftMaxLength.GetValueAtHeight(height))
+	if maxSigChainLen > 0 && sigChainLen > maxSigChainLen {
+		sigChainLen = maxSigChainLen
+	}
 	rightShiftBytes(sigHash, bitShiftPerSigChainElement*sigChainLen)
 	return sigHash
 }

por/porpackage.go

@@ -109,7 +109,7 @@ func NewPorPackage(txn *transaction.Transaction, shouldVerify bool) (*PorPackage
 	}
 
 	txHash := txn.Hash()
-	sigHash, err := sigChain.SignatureHash()
+	sigHash, err := sigChain.SignatureHash(height)
 	if err != nil {
 		return nil, err
 	}

por/porserver.go

@@ -367,9 +367,20 @@ func (ps *PorServer) ShouldSignDestSigChainElem(blockHash, lastHash []byte, sigC
 	if _, ok := ps.finalizedBlockCache.Get(blockHash); ok {
 		return false
 	}
+
+	blockHashUint256, err := common.Uint256ParseFromBytes(blockHash)
+	if err != nil {
+		return false
+	}
+
+	height, err := Store.GetHeightByBlockHash(blockHashUint256)
+	if err != nil {
+		return false
+	}
+
 	if v, ok := ps.destSigChainElemCache.Get(blockHash); ok {
 		if currentDestSigChainElem, ok := v.(*destSigChainElem); ok {
-			sigHash := pb.ComputeSignatureHash(lastHash, sigChainLen)
+			sigHash := pb.ComputeSignatureHash(lastHash, sigChainLen, height)
 			if bytes.Compare(sigHash, currentDestSigChainElem.sigHash) >= 0 {
 				return false
 			}
@@ -386,8 +397,18 @@ func (ps *PorServer) AddDestSigChainElem(blockHash, lastHash []byte, sigChainLen
 		return false, nil
 	}
 
-	err := ps.destSigChainElemCache.Set(blockHash, &destSigChainElem{
-		sigHash:      pb.ComputeSignatureHash(lastHash, sigChainLen),
+	blockHashUint256, err := common.Uint256ParseFromBytes(blockHash)
+	if err != nil {
+		return false, err
+	}
+
+	height, err := Store.GetHeightByBlockHash(blockHashUint256)
+	if err != nil {
+		return false, err
+	}
+
+	err = ps.destSigChainElemCache.Set(blockHash, &destSigChainElem{
+		sigHash:      pb.ComputeSignatureHash(lastHash, sigChainLen, height),
 		sigChainElem: destElem,
 		prevHash:     lastHash,
 	})