7 log "github.com/sirupsen/logrus"
9 "github.com/vapor/config"
10 "github.com/vapor/errors"
11 "github.com/vapor/event"
12 "github.com/vapor/protocol/bc"
13 "github.com/vapor/protocol/bc/types"
14 "github.com/vapor/protocol/state"
18 maxSignatureCacheSize = 10000
22 errDoubleSignBlock = errors.New("the consensus is double sign in same height of different block")
23 errInvalidSignature = errors.New("the signature of block is invalid")
24 errSignForkChain = errors.New("can not sign fork before the irreversible block")
27 func signCacheKey(blockHash, pubkey string) string {
28 return fmt.Sprintf("%s:%s", blockHash, pubkey)
31 func (c *Chain) checkDoubleSign(bh *types.BlockHeader, xPub string) error {
32 blockHashes, err := c.store.GetBlockHashesByHeight(bh.Height)
37 for _, blockHash := range blockHashes {
38 if *blockHash == bh.Hash() {
42 blockHeader, err := c.store.GetBlockHeader(blockHash)
47 consensusNode, err := c.getConsensusNode(&blockHeader.PreviousBlockHash, xPub)
48 if err == errNotFoundConsensusNode {
50 } else if err != nil {
54 if blockHeader.BlockWitness.Get(consensusNode.Order) != nil {
55 return errDoubleSignBlock
61 func (c *Chain) checkNodeSign(bh *types.BlockHeader, consensusNode *state.ConsensusNode, signature []byte) error {
62 if !consensusNode.XPub.Verify(bh.Hash().Bytes(), signature) {
63 return errInvalidSignature
66 return c.checkDoubleSign(bh, consensusNode.XPub.String())
69 func (c *Chain) isIrreversible(blockHeader *types.BlockHeader) bool {
70 consensusNodes, err := c.getConsensusNodes(&blockHeader.PreviousBlockHash)
76 for i := 0; i < len(consensusNodes); i++ {
77 if blockHeader.BlockWitness.Get(uint64(i)) != nil {
82 return signCount > len(consensusNodes)*2/3
85 func (c *Chain) updateBlockSignature(blockHeader *types.BlockHeader, nodeOrder uint64, signature []byte) error {
86 blockHeader.Set(nodeOrder, signature)
87 if err := c.store.SaveBlockHeader(blockHeader); err != nil {
91 if !c.isIrreversible(blockHeader) || blockHeader.Height <= c.lastIrrBlockHeader.Height {
95 if c.InMainChain(blockHeader.Hash()) {
96 if err := c.store.SaveChainStatus(c.bestBlockHeader, blockHeader, []*types.BlockHeader{}, state.NewUtxoViewpoint(), []*state.ConsensusResult{}); err != nil {
100 c.lastIrrBlockHeader = blockHeader
102 // block is on a forked chain
103 log.WithFields(log.Fields{"module": logModule}).Info("majority votes received on forked chain")
104 tail, err := c.traceLongestChainTail(blockHeader)
109 return c.reorganizeChain(tail)
114 // validateSign verify the signatures of block, and return the number of correct signature
115 // if some signature is invalid, they will be reset to nil
116 // if the block does not have the signature of blocker, it will return error
117 func (c *Chain) validateSign(block *types.Block) error {
118 consensusNodeMap, err := c.getConsensusNodes(&block.PreviousBlockHash)
123 blocker, err := c.GetBlocker(&block.PreviousBlockHash, block.Timestamp)
128 hasBlockerSign := false
129 blockHash := block.Hash()
130 for pubKey, node := range consensusNodeMap {
131 if block.BlockWitness.Get(node.Order) == nil {
132 cachekey := signCacheKey(blockHash.String(), pubKey)
133 if signature, ok := c.signatureCache.Get(cachekey); ok {
134 block.Set(node.Order, signature.([]byte))
135 c.signatureCache.Remove(cachekey)
141 if err := c.checkNodeSign(&block.BlockHeader, node, block.Get(node.Order)); err == errDoubleSignBlock {
142 log.WithFields(log.Fields{"module": logModule, "blockHash": blockHash.String(), "pubKey": pubKey}).Warn("the consensus node double sign the same height of different block")
143 block.BlockWitness.Delete(node.Order)
145 } else if err != nil {
149 if blocker == pubKey {
150 hasBlockerSign = true
155 return errors.New("the block has no signature of the blocker")
160 // ProcessBlockSignature process the received block signature messages
161 // return whether a block become irreversible, if so, the chain module must update status
162 func (c *Chain) ProcessBlockSignature(signature, xPub []byte, blockHash *bc.Hash) error {
163 xpubStr := hex.EncodeToString(xPub[:])
164 blockHeader, _ := c.store.GetBlockHeader(blockHash)
166 // save the signature if the block is not exist
167 if blockHeader == nil {
168 cacheKey := signCacheKey(blockHash.String(), xpubStr)
169 c.signatureCache.Add(cacheKey, signature)
173 consensusNode, err := c.getConsensusNode(&blockHeader.PreviousBlockHash, xpubStr)
178 if blockHeader.BlockWitness.Get(consensusNode.Order) != nil {
183 defer c.cond.L.Unlock()
184 if err := c.checkNodeSign(blockHeader, consensusNode, signature); err != nil {
188 if err := c.updateBlockSignature(blockHeader, consensusNode.Order, signature); err != nil {
191 return c.eventDispatcher.Post(event.BlockSignatureEvent{BlockHash: *blockHash, Signature: signature, XPub: xPub})
194 // SignBlock signing the block if current node is consensus node
195 func (c *Chain) SignBlock(block *types.Block) ([]byte, error) {
196 xprv := config.CommonConfig.PrivateKey()
197 xpubStr := xprv.XPub().String()
198 node, err := c.getConsensusNode(&block.PreviousBlockHash, xpubStr)
199 if err == errNotFoundConsensusNode {
201 } else if err != nil {
205 if err := c.checkDoubleSign(&block.BlockHeader, node.XPub.String()); err == errDoubleSignBlock {
207 } else if err != nil {
211 signature := block.Get(node.Order)
212 if len(signature) == 0 {
213 signature = xprv.Sign(block.Hash().Bytes())
214 block.Set(node.Order, signature)
216 return signature, nil