[sync] added commit sig verification logic to legacy sync

api/service/legacysync/downloader/client.go

@@ -91,6 +91,23 @@ func (client *Client) GetBlocks(hashes [][]byte) *pb.DownloaderResponse {
 	return response
 }
 
+// GetBlocksAndSigs get blockWithSig in serialization byte array by calling a grpc request
+func (client *Client) GetBlocksAndSigs(hashes [][]byte) *pb.DownloaderResponse {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	request := &pb.DownloaderRequest{Type: pb.DownloaderRequest_BLOCKWITHSIG}
+	request.Hashes = make([][]byte, len(hashes))
+	for i := range hashes {
+		request.Hashes[i] = make([]byte, len(hashes[i]))
+		copy(request.Hashes[i], hashes[i])
+	}
+	response, err := client.dlClient.Query(ctx, request)
+	if err != nil {
+		utils.Logger().Error().Err(err).Str("target", client.conn.Target()).Msg("[SYNC] downloader/client.go:GetBlocksAndSigs query failed")
+	}
+	return response
+}
+
 // Register will register node's ip/port information to peers receive newly created blocks in future
 // hash is the bytes of "ip:port" string representation
 func (client *Client) Register(hash []byte, ip, port string) *pb.DownloaderResponse {

api/service/legacysync/downloader/proto/downloader.pb.go

@@ -40,6 +40,7 @@ const (
 	DownloaderRequest_REGISTERTIMEOUT DownloaderRequest_RequestType = 5
 	DownloaderRequest_UNKNOWN         DownloaderRequest_RequestType = 6
 	DownloaderRequest_BLOCKHEADER     DownloaderRequest_RequestType = 7
+	DownloaderRequest_BLOCKWITHSIG    DownloaderRequest_RequestType = 8
 )
 
 // Enum value maps for DownloaderRequest_RequestType.
@@ -53,6 +54,7 @@ var (
 		5: "REGISTERTIMEOUT",
 		6: "UNKNOWN",
 		7: "BLOCKHEADER",
+		8: "BLOCKWITHSIG",
 	}
 	DownloaderRequest_RequestType_value = map[string]int32{
 		"BLOCKHASH":       0,
@@ -63,6 +65,7 @@ var (
 		"REGISTERTIMEOUT": 5,
 		"UNKNOWN":         6,
 		"BLOCKHEADER":     7,
+		"BLOCKWITHSIG":    8,
 	}
 )
 
@@ -310,7 +313,7 @@ var File_downloader_proto protoreflect.FileDescriptor
 
 var file_downloader_proto_rawDesc = []byte{
 	0x0a, 0x10, 0x64, 0x6f, 0x77, 0x6e, 0x6c, 0x6f, 0x61, 0x64, 0x65, 0x72, 0x2e, 0x70, 0x72, 0x6f,
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@@ -324,7 +327,7 @@ var file_downloader_proto_rawDesc = []byte{
 	0x6b, 0x48, 0x61, 0x73, 0x68, 0x12, 0x0e, 0x0a, 0x02, 0x69, 0x70, 0x18, 0x05, 0x20, 0x01, 0x28,
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@@ -333,26 +336,27 @@ var file_downloader_proto_rawDesc = []byte{
 	0x45, 0x52, 0x10, 0x04, 0x12, 0x13, 0x0a, 0x0f, 0x52, 0x45, 0x47, 0x49, 0x53, 0x54, 0x45, 0x52,
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 }
 
 var (

api/service/legacysync/downloader/proto/downloader.proto

@@ -18,6 +18,7 @@ message DownloaderRequest {
     REGISTERTIMEOUT = 5;
     UNKNOWN = 6;
     BLOCKHEADER = 7;
+    BLOCKWITHSIG = 8;
   }
 
   // Request type.

api/service/legacysync/syncing.go

@@ -11,6 +11,8 @@ import (
 	"sync"
 	"time"
 
+	"github.com/harmony-one/harmony/internal/chain"
+
 	"github.com/Workiva/go-datastructures/queue"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/rlp"
@@ -280,9 +282,16 @@ func CompareSyncPeerConfigByblockHashes(a *SyncPeerConfig, b *SyncPeerConfig) in
 	return 0
 }
 
+// BlockWithSig the serialization structure for request DownloaderRequest_BLOCKWITHSIG
+// The block is encoded as block + commit signature
+type BlockWithSig struct {
+	Block              *types.Block
+	CommitSigAndBitmap []byte
+}
+
 // GetBlocks gets blocks by calling grpc request to the corresponding peer.
 func (peerConfig *SyncPeerConfig) GetBlocks(hashes [][]byte) ([][]byte, error) {
-	response := peerConfig.client.GetBlocks(hashes)
+	response := peerConfig.client.GetBlocksAndSigs(hashes)
 	if response == nil {
 		return nil, ErrGetBlock
 	}
@@ -620,8 +629,8 @@ func (ss *StateSync) handleBlockSyncResult(payload [][]byte, tasks syncBlockTask
 	}
 
 	for i, blockBytes := range payload {
-		var blockObj types.Block
+		var bws BlockWithSig
-		if err := rlp.DecodeBytes(blockBytes, &blockObj); err != nil {
+		if err := rlp.DecodeBytes(blockBytes, &bws); err != nil {
 			utils.Logger().Warn().
 				Err(err).
 				Int("taskIndex", tasks[i].index).
@@ -630,6 +639,8 @@ func (ss *StateSync) handleBlockSyncResult(payload [][]byte, tasks syncBlockTask
 			failedTasks = append(failedTasks, tasks[i])
 			continue
 		}
+		blockObj := bws.Block
+		blockObj.SetCurrentCommitSig(bws.CommitSigAndBitmap)
 		gotHash := blockObj.Hash()
 		if !bytes.Equal(gotHash[:], tasks[i].blockHash) {
 			utils.Logger().Warn().
@@ -640,7 +651,7 @@ func (ss *StateSync) handleBlockSyncResult(payload [][]byte, tasks syncBlockTask
 			continue
 		}
 		ss.syncMux.Lock()
-		ss.commonBlocks[tasks[i].index] = &blockObj
+		ss.commonBlocks[tasks[i].index] = blockObj
 		ss.syncMux.Unlock()
 	}
 	return failedTasks
@@ -771,6 +782,15 @@ func (ss *StateSync) UpdateBlockAndStatus(block *types.Block, bc *core.BlockChai
 		if verifyAllSig {
 			verifySig = true
 		}
+		if verifySig {
+			sig, bitmap, err := chain.ParseCommitSigAndBitmap(block.GetCurrentCommitSig())
+			if err != nil {
+				return errors.Wrap(err, "parse commitSigAndBitmap")
+			}
+			if err := bc.Engine().VerifyHeaderSignature(bc, block.Header(), sig, bitmap); err != nil {
+				return errors.Wrapf(err, "verify header signature %v", block.Hash().String())
+			}
+		}
 		err := bc.Engine().VerifyHeader(bc, block.Header(), verifySig)
 		if err == engine.ErrUnknownAncestor {
 			return err
@@ -807,6 +827,12 @@ func (ss *StateSync) UpdateBlockAndStatus(block *types.Block, bc *core.BlockChai
 		Str("blockHex", block.Hash().Hex()).
 		Uint32("ShardID", block.ShardID()).
 		Msg("[SYNC] UpdateBlockAndStatus: New Block Added to Blockchain")
+
+	if verifyAllSig {
+		if err := bc.WriteCommitSig(block.NumberU64(), block.GetCurrentCommitSig()); err != nil {
+			return err
+		}
+	}
 	for i, tx := range block.StakingTransactions() {
 		utils.Logger().Info().
 			Msgf(
@@ -822,16 +848,19 @@ func (ss *StateSync) generateNewState(bc *core.BlockChain, worker *worker.Worker
 	parentHash := bc.CurrentBlock().Hash()
 
 	var err error
-	for {
+	for block := ss.getBlockFromOldBlocksByParentHash(parentHash); ; {
-		block := ss.getBlockFromOldBlocksByParentHash(parentHash)
 		if block == nil {
 			break
 		}
-		err = ss.UpdateBlockAndStatus(block, bc, worker, false)
+		next := ss.getBlockFromOldBlocksByParentHash(block.Hash())
+		// Enforce sig check for the last block in a batch
+		enforceSigCheck := next == nil
+
+		err = ss.UpdateBlockAndStatus(block, bc, worker, enforceSigCheck)
 		if err != nil {
 			break
 		}
-		parentHash = block.Hash()
+		block = next
 	}
 	ss.syncMux.Lock()
 	ss.commonBlocks = make(map[int]*types.Block)
@@ -844,7 +873,7 @@ func (ss *StateSync) generateNewState(bc *core.BlockChain, worker *worker.Worker
 		if block == nil {
 			break
 		}
-		err = ss.UpdateBlockAndStatus(block, bc, worker, false)
+		err = ss.UpdateBlockAndStatus(block, bc, worker, true)
 		if err != nil {
 			break
 		}
@@ -865,7 +894,7 @@ func (ss *StateSync) generateNewState(bc *core.BlockChain, worker *worker.Worker
 		if block == nil {
 			break
 		}
-		err = ss.UpdateBlockAndStatus(block, bc, worker, false)
+		err = ss.UpdateBlockAndStatus(block, bc, worker, true)
 		if err != nil {
 			break
 		}

internal/chain/engine.go

@@ -395,6 +395,9 @@ func applySlashes(
 // i.e. this header verification api is more flexible since the caller specifies which commit signature and bitmap to use
 // for verifying the block header, which is necessary for cross-shard block header verification. Example of such is cross-shard transaction.
 func (e *engineImpl) VerifyHeaderSignature(chain engine.ChainReader, header *block.Header, commitSig bls_cosi.SerializedSignature, commitBitmap []byte) error {
+	if chain.CurrentHeader().Number().Uint64() <= uint64(1) {
+		return nil
+	}
 	return e.verifyHeaderSignatureCached(chain, header, commitSig, commitBitmap)
 }
 

node/node_syncing.go

@@ -449,6 +449,18 @@ func (node *Node) CalculateResponse(request *downloader_pb.DownloaderRequest, in
 			}
 		}
 
+	case downloader_pb.DownloaderRequest_BLOCKWITHSIG:
+		var hash common.Hash
+		for _, bytes := range request.Hashes {
+			hash.SetBytes(bytes)
+			encoded, err := node.getEncodedBlockWithSigByHash(hash)
+			if err != nil {
+				utils.Logger().Info().Err(err).Str("hash", hash.String()).Msg("failed to get block with sig")
+				continue
+			}
+			response.Payload = append(response.Payload, encoded)
+		}
+
 	case downloader_pb.DownloaderRequest_BLOCKHEIGHT:
 		response.BlockHeight = node.Blockchain().CurrentBlock().NumberU64()
 
@@ -513,19 +525,23 @@ func (node *Node) CalculateResponse(request *downloader_pb.DownloaderRequest, in
 				Int("number", count).
 				Msg("[SYNC] extra node registered")
 		}
+
 	}
+
 	return response, nil
 }
 
 const (
-	headerCacheSize = 10000
+	headerCacheSize       = 10000
-	blockCacheSize  = 10000
+	blockCacheSize        = 10000
+	blockWithSigCacheSize = 10000
 )
 
 var (
 	// Cached fields for block header and block requests
-	headerReqCache, _ = lru.New(headerCacheSize)
+	headerReqCache, _       = lru.New(headerCacheSize)
-	blockReqCache, _  = lru.New(blockCacheSize)
+	blockReqCache, _        = lru.New(blockCacheSize)
+	blockWithSigReqCache, _ = lru.New(blockWithSigCacheSize)
 
 	errHeaderNotExist = errors.New("header not exist")
 	errBlockNotExist  = errors.New("block not exist")
@@ -563,6 +579,52 @@ func (node *Node) getEncodedBlockByHash(hash common.Hash) ([]byte, error) {
 	return b, nil
 }
 
+func (node *Node) getEncodedBlockWithSigByHash(hash common.Hash) ([]byte, error) {
+	if b, ok := blockWithSigReqCache.Get(hash); ok {
+		return b.([]byte), nil
+	}
+	blk := node.Blockchain().GetBlockByHash(hash)
+	if blk == nil {
+		return nil, errBlockNotExist
+	}
+	sab, err := node.getCommitSigAndBitmap(blk)
+	if err != nil {
+		return nil, err
+	}
+	bwh := legacysync.BlockWithSig{
+		Block:              blk,
+		CommitSigAndBitmap: sab,
+	}
+	b, err := rlp.EncodeToBytes(bwh)
+	if err != nil {
+		return nil, err
+	}
+	blockWithSigReqCache.Add(hash, b)
+	return b, nil
+}
+
+func (node *Node) getCommitSigAndBitmap(block *types.Block) ([]byte, error) {
+	child := node.Blockchain().GetBlockByNumber(block.NumberU64() + 1)
+	if child == nil {
+		return node.getCommitSigFromChild(block, child)
+	}
+	return node.getCommitSigFromDB(block)
+}
+
+func (node *Node) getCommitSigFromChild(parent, child *types.Block) ([]byte, error) {
+	if child.ParentHash() != parent.Hash() {
+		return nil, fmt.Errorf("child's parent hash unexpected: %v / %v",
+			child.ParentHash().String(), parent.Hash().String())
+	}
+	sig := child.Header().LastCommitSignature()
+	bitmap := child.Header().LastCommitBitmap()
+	return append(sig[:], bitmap...), nil
+}
+
+func (node *Node) getCommitSigFromDB(block *types.Block) ([]byte, error) {
+	return node.Blockchain().ReadCommitSig(block.NumberU64())
+}
+
 // SyncStatus return the syncing status, including whether node is syncing
 // and the target block number.
 func (node *Node) SyncStatus(shardID uint32) (bool, uint64) {