fix justify and finalize logic

consensus/consensus.go

@@ -150,7 +150,7 @@ type PoSA interface {
 	IsLocalBlock(header *types.Header) bool
 	AllowLightProcess(chain ChainReader, currentHeader *types.Header) bool
 	GetJustifiedHeader(chain ChainHeaderReader, header *types.Header) *types.Header
-	GetFinalizedHeader(chain ChainHeaderReader, header *types.Header) *types.Header
+	GetFinalizedHeader(chain ChainHeaderReader, header *types.Header, backward uint64) *types.Header
 	VerifyVote(chain ChainHeaderReader, vote *types.VoteEnvelope) error
 	IsActiveValidatorAt(chain ChainHeaderReader, header *types.Header) bool
 }

consensus/parlia/parlia.go

@@ -1685,38 +1685,42 @@ func (p *Parlia) GetJustifiedHeader(chain consensus.ChainHeaderReader, header *t
 		return nil
 	}
 
-	// There won't any attestation in first two blocks, return root.
-	if header.Number.Uint64() < 2 {
-		return chain.GetHeaderByNumber(0)
-	}
-
 	snap, err := p.snapshot(chain, header.Number.Uint64(), header.Hash(), nil)
 	if err != nil {
 		log.Error("Unexpected error when getting snapshot",
 			"error", err, "blockNumber", header.Number.Uint64(), "blockHash", header.Hash())
 		return nil
 	}
 
-	// If there is no vote justified block, then return root.
+	// If there is no vote justified block, then return root or naturally justified block.
 	if snap.Attestation == nil {
-		return chain.GetHeaderByNumber(0)
+		if header.Number.Uint64() <= naturallyJustifiedDist {
+			return chain.GetHeaderByNumber(0)
+		}
+		// Return naturally justified block.
+		return FindAncientHeader(header, naturallyJustifiedDist, chain, nil)
 	}
-	// Return naturally justified block.
+
+	// If the latest vote justified block is too far, return naturally justified block.
 	if snap.Number-snap.Attestation.TargetNumber > naturallyJustifiedDist {
 		return FindAncientHeader(header, naturallyJustifiedDist, chain, nil)
 	}
 	//Return latest vote justified block.
 	return chain.GetHeaderByHash(snap.Attestation.TargetHash)
 }
 
-// GetFinalizedHeader returns highest finalized block header before the specific block,
-// the attestation within the specific block will be taken into account.
-func (p *Parlia) GetFinalizedHeader(chain consensus.ChainHeaderReader, header *types.Header) *types.Header {
+// GetFinalizedHeader returns highest finalized block header before the specific block.
+// It will first to find vote finalized block within the specific backward blocks, the suggested backward blocks is 21.
+// If the vote finalized block not found, return its previous backward block.
+func (p *Parlia) GetFinalizedHeader(chain consensus.ChainHeaderReader, header *types.Header, backward uint64) *types.Header {
+	if chain == nil || header == nil {
+		return nil
+	}
 	if !chain.Config().IsLynn(header.Number) {
 		return chain.GetHeaderByNumber(0)
 	}
-	if chain == nil || header == nil || header.Number.Uint64() < 2 {
-		return chain.GetHeaderByNumber(0)
+	if header.Number.Uint64() < backward {
+		backward = header.Number.Uint64()
 	}
 
 	snap, err := p.snapshot(chain, header.Number.Uint64(), header.Hash(), nil)
@@ -1726,7 +1730,7 @@ func (p *Parlia) GetFinalizedHeader(chain consensus.ChainHeaderReader, header *t
 		return nil
 	}
 
-	for snap.Attestation != nil {
+	for snap.Attestation != nil && snap.Attestation.SourceNumber >= header.Number.Uint64()-backward {
 		if snap.Attestation.TargetNumber == snap.Attestation.SourceNumber+1 {
 			return chain.GetHeaderByHash(snap.Attestation.SourceHash)
 		}
@@ -1739,7 +1743,7 @@ func (p *Parlia) GetFinalizedHeader(chain consensus.ChainHeaderReader, header *t
 		}
 	}
 
-	return chain.GetHeaderByNumber(0)
+	return FindAncientHeader(header, backward, chain, nil)
 }
 
 // ===========================     utility function        ==========================

core/blockchain.go

@@ -545,14 +545,35 @@ func (bc *BlockChain) getJustifiedNumber(header *types.Header) uint64 {
 // getFinalizedNumber returns the highest finalized number before the specific block.
 func (bc *BlockChain) getFinalizedNumber(header *types.Header) uint64 {
 	if p, ok := bc.engine.(consensus.PoSA); ok {
-		if finalizedHeader := p.GetFinalizedHeader(bc, header); finalizedHeader != nil {
+		if finalizedHeader := p.GetFinalizedHeader(bc, header, types.NaturallyFinalizedDist); finalizedHeader != nil {
 			return finalizedHeader.Number.Uint64()
 		}
 	}
 
 	return 0
 }
 
+// isFinalizedBlockHigher returns true when the new block's finalized block is higher than current block.
+func (bc *BlockChain) isFinalizedBlockHigher(header *types.Header, curHeader *types.Header) bool {
+	p, ok := bc.engine.(consensus.PoSA)
+	if !ok {
+		return false
+	}
+
+	ancestor := rawdb.FindCommonAncestor(bc.db, header, curHeader)
+	if ancestor == nil {
+		return false
+	}
+
+	finalized := p.GetFinalizedHeader(bc, header, header.Number.Uint64()-ancestor.Number.Uint64())
+	curFinalized := p.GetFinalizedHeader(bc, curHeader, curHeader.Number.Uint64()-ancestor.Number.Uint64())
+	if finalized == nil || curFinalized == nil {
+		return false
+	}
+
+	return finalized.Number.Uint64() > curFinalized.Number.Uint64()
+}
+
 // loadLastState loads the last known chain state from the database. This method
 // assumes that the chain manager mutex is held.
 func (bc *BlockChain) loadLastState() error {
@@ -1842,7 +1863,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
 	reorg := externTd.Cmp(localTd) > 0
 	currentBlock = bc.CurrentBlock()
-	if bc.getFinalizedNumber(block.Header()) > bc.getFinalizedNumber(currentBlock.Header()) {
+	if bc.isFinalizedBlockHigher(block.Header(), currentBlock.Header()) {
 		reorg = true
 	}
 	if !reorg && externTd.Cmp(localTd) == 0 {
@@ -1890,7 +1911,7 @@ func (bc *BlockChain) writeBlockWithState(block *types.Block, receipts []*types.
 		if emitHeadEvent {
 			bc.chainHeadFeed.Send(ChainHeadEvent{Block: block})
 			if posa, ok := bc.Engine().(consensus.PoSA); ok {
-				if finalizedHeader := posa.GetFinalizedHeader(bc, block.Header()); finalizedHeader != nil {
+				if finalizedHeader := posa.GetFinalizedHeader(bc, block.Header(), types.NaturallyFinalizedDist); finalizedHeader != nil {
 					bc.finalizedHeaderFeed.Send(FinalizedHeaderEvent{finalizedHeader})
 				}
 			}
@@ -1997,7 +2018,7 @@ func (bc *BlockChain) insertChain(chain types.Blocks, verifySeals bool) (int, er
 		if lastCanon != nil && bc.CurrentBlock().Hash() == lastCanon.Hash() {
 			bc.chainHeadFeed.Send(ChainHeadEvent{lastCanon})
 			if posa, ok := bc.Engine().(consensus.PoSA); ok {
-				if finalizedHeader := posa.GetFinalizedHeader(bc, lastCanon.Header()); finalizedHeader != nil {
+				if finalizedHeader := posa.GetFinalizedHeader(bc, lastCanon.Header(), types.NaturallyFinalizedDist); finalizedHeader != nil {
 					bc.finalizedHeaderFeed.Send(FinalizedHeaderEvent{finalizedHeader})
 				}
 			}

core/headerchain.go

@@ -133,14 +133,35 @@ func (hc *HeaderChain) getJustifiedNumber(header *types.Header) uint64 {
 // getFinalizedNumber returns the highest finalized number before the specific block.
 func (hc *HeaderChain) getFinalizedNumber(header *types.Header) uint64 {
 	if p, ok := hc.engine.(consensus.PoSA); ok {
-		if finalizedHeader := p.GetFinalizedHeader(hc, header); finalizedHeader != nil {
+		if finalizedHeader := p.GetFinalizedHeader(hc, header, types.NaturallyFinalizedDist); finalizedHeader != nil {
 			return finalizedHeader.Number.Uint64()
 		}
 	}
 
 	return 0
 }
 
+// isFinalizedBlockHigher returns true when the new block's finalized block is higher than current block.
+func (hc *HeaderChain) isFinalizedBlockHigher(header *types.Header, curHeader *types.Header) bool {
+	p, ok := hc.engine.(consensus.PoSA)
+	if !ok {
+		return false
+	}
+
+	ancestor := rawdb.FindCommonAncestor(hc.chainDb, header, curHeader)
+	if ancestor == nil {
+		return false
+	}
+
+	finalized := p.GetFinalizedHeader(hc, header, header.Number.Uint64()-ancestor.Number.Uint64())
+	curFinalized := p.GetFinalizedHeader(hc, curHeader, curHeader.Number.Uint64()-ancestor.Number.Uint64())
+	if finalized == nil || curFinalized == nil {
+		return false
+	}
+
+	return finalized.Number.Uint64() > curFinalized.Number.Uint64()
+}
+
 // GetBlockNumber retrieves the block number belonging to the given hash
 // from the cache or database
 func (hc *HeaderChain) GetBlockNumber(hash common.Hash) *uint64 {
@@ -241,7 +262,7 @@ func (hc *HeaderChain) writeHeaders(headers []*types.Header) (result *headerWrit
 	// Second clause in the if statement reduces the vulnerability to selfish mining.
 	// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
 	reorg := newTD.Cmp(localTD) > 0
-	if hc.getFinalizedNumber(lastHeader) > hc.getFinalizedNumber(hc.CurrentHeader()) {
+	if hc.isFinalizedBlockHigher(lastHeader, hc.CurrentHeader()) {
 		reorg = true
 	}
 	if !reorg && newTD.Cmp(localTD) == 0 {

core/types/vote.go

@@ -14,13 +14,14 @@ const (
 	BLSSignatureLength = 96
 
 	MaxAttestationExtraLength = 256
+	NaturallyFinalizedDist    = 21 // The distance to naturally finalized a block
 )
 
 type BLSPublicKey [BLSPublicKeyLength]byte
 type BLSSignature [BLSSignatureLength]byte
 type ValidatorsBitSet uint64
 
-// VoteData represents the vote data that validator voted for fast finality.
+// VoteData represents the vote range that validator voted for fast finality.
 type VoteData struct {
 	SourceNumber uint64      // The source block number should be the latest justified block number.
 	SourceHash   common.Hash // The block hash of the source block.

internal/ethapi/api.go

@@ -1328,7 +1328,7 @@ func (s *PublicBlockChainAPI) GetFinalizedHeader(ctx context.Context, blockNrOrH
 	}
 
 	if posa, ok := s.b.Engine().(consensus.PoSA); ok {
-		return posa.GetFinalizedHeader(s.b.Chain(), header), nil
+		return posa.GetFinalizedHeader(s.b.Chain(), header, types.NaturallyFinalizedDist), nil
 	}
 
 	// Not support.

light/lightchain.go

@@ -419,7 +419,7 @@ func (lc *LightChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (i
 	case core.CanonStatTy:
 		events = append(events, core.ChainEvent{Block: block, Hash: block.Hash()})
 		if posa, ok := lc.Engine().(consensus.PoSA); ok {
-			events = append(events, core.FinalizedHeaderEvent{Header: posa.GetFinalizedHeader(lc, block.Header())})
+			events = append(events, core.FinalizedHeaderEvent{Header: posa.GetFinalizedHeader(lc, block.Header(), types.NaturallyFinalizedDist)})
 		}
 	case core.SideStatTy:
 		events = append(events, core.ChainSideEvent{Block: block})