X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;ds=sidebyside;f=protocol%2Fbbft.go;fp=protocol%2Fbbft.go;h=6c6194956927d7f9f131fd7be7d6494dfefcb701;hb=54373c1a3efe0e373ec1605840a4363e4b246c46;hp=0000000000000000000000000000000000000000;hpb=ee01d543fdfe1fd0a4d548965c66f7923ea7b062;p=bytom%2Fvapor.git

diff --git a/protocol/bbft.go b/protocol/bbft.go
new file mode 100644
index 00000000..6c619495
--- /dev/null
+++ b/protocol/bbft.go
@@ -0,0 +1,238 @@
+package protocol
+
+import (
+	"encoding/hex"
+	"fmt"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/vapor/config"
+	"github.com/vapor/errors"
+	"github.com/vapor/event"
+	"github.com/vapor/protocol/bc"
+	"github.com/vapor/protocol/bc/types"
+	"github.com/vapor/protocol/state"
+)
+
+const (
+	maxSignatureCacheSize = 10000
+)
+
+var (
+	errVotingOperationOverFlow = errors.New("voting operation result overflow")
+	errDoubleSignBlock         = errors.New("the consensus is double sign in same height of different block")
+	errInvalidSignature        = errors.New("the signature of block is invalid")
+	errSignForkChain           = errors.New("can not sign fork before the irreversible block")
+)
+
+func signCacheKey(blockHash, pubkey string) string {
+	return fmt.Sprintf("%s:%s", blockHash, pubkey)
+}
+
+func (c *Chain) isIrreversible(blockNode *state.BlockNode) bool {
+	consensusNodes, err := c.consensusNodeManager.getConsensusNodes(&blockNode.Parent.Hash)
+	if err != nil {
+		return false
+	}
+
+	signCount := 0
+	for i := 0; i < len(consensusNodes); i++ {
+		if ok, _ := blockNode.BlockWitness.Test(uint32(i)); ok {
+			signCount++
+		}
+	}
+
+	return signCount > len(consensusNodes)*2/3
+}
+
+// GetVoteResultByHash return vote result by block hash
+func (c *Chain) GetVoteResultByHash(blockHash *bc.Hash) (*state.VoteResult, error) {
+	blockNode := c.index.GetNode(blockHash)
+	return c.consensusNodeManager.getVoteResult(state.CalcVoteSeq(blockNode.Height), blockNode)
+}
+
+// IsBlocker returns whether the consensus node is a blocker at the specified time
+func (c *Chain) IsBlocker(prevBlockHash *bc.Hash, pubKey string, timeStamp uint64) (bool, error) {
+	xPub, err := c.consensusNodeManager.getBlocker(prevBlockHash, timeStamp)
+	if err != nil {
+		return false, err
+	}
+	return xPub == pubKey, nil
+}
+
+// GetBlock return blocker by specified timestamp
+func (c *Chain) GetBlocker(prevBlockHash *bc.Hash, timestamp uint64) (string, error) {
+	return c.consensusNodeManager.getBlocker(prevBlockHash, timestamp)
+}
+
+// ProcessBlockSignature process the received block signature messages
+// return whether a block become irreversible, if so, the chain module must update status
+func (c *Chain) ProcessBlockSignature(signature, xPub []byte, blockHash *bc.Hash) error {
+	xpubStr := hex.EncodeToString(xPub[:])
+	blockNode := c.index.GetNode(blockHash)
+	// save the signature if the block is not exist
+	if blockNode == nil {
+		cacheKey := signCacheKey(blockHash.String(), xpubStr)
+		c.signatureCache.Add(cacheKey, signature)
+		return nil
+	}
+
+	consensusNode, err := c.consensusNodeManager.getConsensusNode(&blockNode.Parent.Hash, xpubStr)
+	if err != nil {
+		return err
+	}
+
+	if exist, _ := blockNode.BlockWitness.Test(uint32(consensusNode.Order)); exist {
+		return nil
+	}
+
+	c.cond.L.Lock()
+	defer c.cond.L.Unlock()
+	if err := c.checkNodeSign(blockNode.BlockHeader(), consensusNode, signature); err != nil {
+		return err
+	}
+
+	if err := c.updateBlockSignature(blockNode, consensusNode.Order, signature); err != nil {
+		return err
+	}
+	return c.eventDispatcher.Post(event.BlockSignatureEvent{BlockHash: *blockHash, Signature: signature, XPub: xPub})
+}
+
+// validateSign verify the signatures of block, and return the number of correct signature
+// if some signature is invalid, they will be reset to nil
+// if the block has not the signature of blocker, it will return error
+func (c *Chain) validateSign(block *types.Block) error {
+	consensusNodeMap, err := c.consensusNodeManager.getConsensusNodes(&block.PreviousBlockHash)
+	if err != nil {
+		return err
+	}
+
+	hasBlockerSign := false
+	blockHash := block.Hash()
+	for pubKey, node := range consensusNodeMap {
+		if len(block.Witness) <= int(node.Order) {
+			continue
+		}
+
+		if block.Get(node.Order) == nil {
+			cachekey := signCacheKey(blockHash.String(), pubKey)
+			if signature, ok := c.signatureCache.Get(cachekey); ok {
+				block.Set(node.Order, signature.([]byte))
+			} else {
+				continue
+			}
+		}
+
+		if err := c.checkNodeSign(&block.BlockHeader, node, block.Get(node.Order)); err == errDoubleSignBlock {
+			log.WithFields(log.Fields{"module": logModule, "blockHash": blockHash.String(), "pubKey": pubKey}).Warn("the consensus node double sign the same height of different block")
+			block.Delete(node.Order)
+			continue
+		} else if err != nil {
+			return err
+		}
+
+		isBlocker, err := c.IsBlocker(&block.PreviousBlockHash, pubKey, block.Timestamp)
+		if err != nil {
+			return err
+		}
+
+		if isBlocker {
+			hasBlockerSign = true
+		}
+
+	}
+
+	if !hasBlockerSign {
+		return errors.New("the block has no signature of the blocker")
+	}
+	return nil
+}
+
+func (c *Chain) checkNodeSign(bh *types.BlockHeader, consensusNode *state.ConsensusNode, signature []byte) error {
+	if !consensusNode.XPub.Verify(bh.Hash().Bytes(), signature) {
+		return errInvalidSignature
+	}
+
+	blockNodes := c.consensusNodeManager.blockIndex.NodesByHeight(bh.Height)
+	for _, blockNode := range blockNodes {
+		if blockNode.Hash == bh.Hash() {
+			continue
+		}
+
+		consensusNode, err := c.consensusNodeManager.getConsensusNode(&blockNode.Parent.Hash, consensusNode.XPub.String())
+		if err != nil && err != errNotFoundConsensusNode {
+			return err
+		}
+
+		if err == errNotFoundConsensusNode {
+			continue
+		}
+
+		if ok, err := blockNode.BlockWitness.Test(uint32(consensusNode.Order)); err == nil && ok {
+			return errDoubleSignBlock
+		}
+	}
+	return nil
+}
+
+// SignBlock signing the block if current node is consensus node
+func (c *Chain) SignBlock(block *types.Block) ([]byte, error) {
+	xprv := config.CommonConfig.PrivateKey()
+	xpubStr := xprv.XPub().String()
+	node, err := c.consensusNodeManager.getConsensusNode(&block.PreviousBlockHash, xpubStr)
+	if err == errNotFoundConsensusNode {
+		return nil, nil
+	} else if err != nil {
+		return nil, err
+	}
+
+	c.cond.L.Lock()
+	defer c.cond.L.Unlock()
+	//check double sign in same block height
+	blockNodes := c.consensusNodeManager.blockIndex.NodesByHeight(block.Height)
+	for _, blockNode := range blockNodes {
+		// Has already signed the same height block
+		if ok, err := blockNode.BlockWitness.Test(uint32(node.Order)); err == nil && ok {
+			return nil, nil
+		}
+	}
+
+	for blockNode := c.index.GetNode(&block.PreviousBlockHash); !c.index.InMainchain(blockNode.Hash); blockNode = blockNode.Parent {
+		if blockNode.Height <= c.bestIrreversibleNode.Height {
+			return nil, errSignForkChain
+		}
+	}
+
+	signature := block.Get(node.Order)
+	if len(signature) == 0 {
+		signature = xprv.Sign(block.Hash().Bytes())
+		block.Set(node.Order, signature)
+	}
+	return signature, nil
+}
+
+func (c *Chain) updateBlockSignature(blockNode *state.BlockNode, nodeOrder uint64, signature []byte) error {
+	if err := blockNode.BlockWitness.Set(uint32(nodeOrder)); err != nil {
+		return err
+	}
+
+	blockHeader, err := c.store.GetBlockHeader(&blockNode.Hash, blockNode.Height)
+	if err != nil {
+		return err
+	}
+
+	blockHeader.Set(nodeOrder, signature)
+
+	if err := c.store.SaveBlockHeader(blockHeader); err != nil {
+		return err
+	}
+
+	if c.isIrreversible(blockNode) && blockNode.Height > c.bestIrreversibleNode.Height {
+		if err := c.store.SaveChainStatus(c.bestNode, blockNode, state.NewUtxoViewpoint(), []*state.VoteResult{}); err != nil {
+			return err
+		}
+
+		c.bestIrreversibleNode = blockNode
+	}
+	return nil
+}