The core protocol of WoopChain
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woop/consensus/consensus_v2.go

666 lines
23 KiB

package consensus
import (
"bytes"
"encoding/hex"
"time"
protobuf "github.com/golang/protobuf/proto"
msg_pb "github.com/harmony-one/harmony/api/proto/message"
"github.com/harmony-one/harmony/block"
"github.com/harmony-one/harmony/consensus/quorum"
"github.com/harmony-one/harmony/core/types"
vrf_bls "github.com/harmony-one/harmony/crypto/vrf/bls"
nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
"github.com/harmony-one/harmony/p2p"
"github.com/harmony-one/harmony/shard"
"github.com/harmony-one/vdf/src/vdf_go"
"github.com/pkg/errors"
)
// handlemessageupdate will update the consensus state according to received message
func (consensus *Consensus) handleMessageUpdate(payload []byte) {
if len(payload) == 0 {
return
}
msg := &msg_pb.Message{}
if err := protobuf.Unmarshal(payload, msg); err != nil {
consensus.getLogger().Error().Err(err).Msg("Failed to unmarshal message payload.")
return
}
// when node is in ViewChanging mode, it still accepts normal messages into FBFTLog
// in order to avoid possible trap forever but drop PREPARE and COMMIT
// which are message types specifically for a node acting as leader
if (consensus.current.Mode() == ViewChanging) &&
(msg.Type == msg_pb.MessageType_PREPARE ||
msg.Type == msg_pb.MessageType_COMMIT) {
return
}
if msg.Type == msg_pb.MessageType_VIEWCHANGE ||
msg.Type == msg_pb.MessageType_NEWVIEW {
if msg.GetViewchange() != nil &&
msg.GetViewchange().ShardId != consensus.ShardID {
consensus.getLogger().Warn().
Uint32("myShardId", consensus.ShardID).
Uint32("receivedShardId", msg.GetViewchange().ShardId).
Msg("Received view change message from different shard")
return
}
} else {
if msg.GetConsensus() != nil &&
msg.GetConsensus().ShardId != consensus.ShardID {
consensus.getLogger().Warn().
Uint32("myShardId", consensus.ShardID).
Uint32("receivedShardId", msg.GetConsensus().ShardId).
Msg("Received consensus message from different shard")
return
}
}
intendedForValidator, intendedForLeader :=
!consensus.IsLeader(),
consensus.IsLeader()
switch t := msg.Type; true {
// Handle validator intended messages first
case t == msg_pb.MessageType_ANNOUNCE &&
intendedForValidator &&
consensus.validatorSanityChecks(msg):
consensus.onAnnounce(msg)
case t == msg_pb.MessageType_PREPARED &&
intendedForValidator &&
consensus.validatorSanityChecks(msg):
consensus.onPrepared(msg)
case t == msg_pb.MessageType_COMMITTED &&
intendedForValidator &&
consensus.validatorSanityChecks(msg):
consensus.onCommitted(msg)
// Handle leader intended messages now
case t == msg_pb.MessageType_PREPARE &&
intendedForLeader &&
consensus.leaderSanityChecks(msg):
consensus.onPrepare(msg)
case t == msg_pb.MessageType_COMMIT &&
intendedForLeader &&
consensus.leaderSanityChecks(msg):
consensus.onCommit(msg)
case t == msg_pb.MessageType_VIEWCHANGE &&
consensus.viewChangeSanityCheck(msg):
consensus.onViewChange(msg)
case t == msg_pb.MessageType_NEWVIEW &&
consensus.viewChangeSanityCheck(msg):
consensus.onNewView(msg)
}
}
func (consensus *Consensus) finalizeCommits() {
consensus.getLogger().Info().
Int64("NumCommits", consensus.Decider.SignersCount(quorum.Commit)).
Msg("[finalizeCommits] Finalizing Block")
beforeCatchupNum := consensus.blockNum
leaderPriKey, err := consensus.GetConsensusLeaderPrivateKey()
if err != nil {
consensus.getLogger().Error().Err(err).Msg("[FinalizeCommits] leader not found")
return
}
// Construct committed message
network, err := consensus.construct(msg_pb.MessageType_COMMITTED, nil, leaderPriKey.GetPublicKey(), leaderPriKey)
if err != nil {
consensus.getLogger().Warn().Err(err).
Msg("[FinalizeCommits] Unable to construct Committed message")
return
}
msgToSend, aggSig, FBFTMsg :=
network.Bytes,
network.OptionalAggregateSignature,
network.FBFTMsg
consensus.aggregatedCommitSig = aggSig // this may not needed
consensus.FBFTLog.AddMessage(FBFTMsg)
// find correct block content
curBlockHash := consensus.blockHash
block := consensus.FBFTLog.GetBlockByHash(curBlockHash)
if block == nil {
consensus.getLogger().Warn().
Str("blockHash", hex.EncodeToString(curBlockHash[:])).
Msg("[FinalizeCommits] Cannot find block by hash")
return
}
consensus.tryCatchup()
if consensus.blockNum-beforeCatchupNum != 1 {
consensus.getLogger().Warn().
Uint64("beforeCatchupBlockNum", beforeCatchupNum).
Msg("[FinalizeCommits] Leader cannot provide the correct block for committed message")
return
}
if err := consensus.ChainReader.WriteLastCommits(FBFTMsg.Payload); err != nil {
consensus.getLogger().Err(err).
Msg("[FinalizeCommits] could not write last commits")
return
}
// if leader success finalize the block, send committed message to validators
if err := consensus.msgSender.SendWithRetry(
block.NumberU64(),
msg_pb.MessageType_COMMITTED, []nodeconfig.GroupID{
nodeconfig.NewGroupIDByShardID(nodeconfig.ShardID(consensus.ShardID)),
},
p2p.ConstructMessage(msgToSend)); err != nil {
consensus.getLogger().Warn().Err(err).Msg("[finalizeCommits] Cannot send committed message")
} else {
consensus.getLogger().Info().
Hex("blockHash", curBlockHash[:]).
Uint64("blockNum", consensus.blockNum).
Msg("[finalizeCommits] Sent Committed Message")
}
// Dump new block into level db
// In current code, we add signatures in block in tryCatchup, the block dump to explorer does not contains signatures
// but since explorer doesn't need signatures, it should be fine
// in future, we will move signatures to next block
//explorer.GetStorageInstance(consensus.leader.IP, consensus.leader.Port, true).Dump(block, beforeCatchupNum)
if consensus.consensusTimeout[timeoutBootstrap].IsActive() {
consensus.consensusTimeout[timeoutBootstrap].Stop()
consensus.getLogger().Debug().Msg("[finalizeCommits] Start consensus timer; stop bootstrap timer only once")
} else {
consensus.getLogger().Debug().Msg("[finalizeCommits] Start consensus timer")
}
consensus.consensusTimeout[timeoutConsensus].Start()
consensus.getLogger().Info().
Uint64("blockNum", block.NumberU64()).
Uint64("epochNum", block.Epoch().Uint64()).
Uint64("ViewId", block.Header().ViewID().Uint64()).
Str("blockHash", block.Hash().String()).
Int("index", consensus.Decider.IndexOf(consensus.LeaderPubKey)).
Int("numTxns", len(block.Transactions())).
Int("numStakingTxns", len(block.StakingTransactions())).
Msg("HOORAY!!!!!!! CONSENSUS REACHED!!!!!!!")
if n := time.Now(); n.Before(consensus.NextBlockDue) {
// Sleep to wait for the full block time
consensus.getLogger().Debug().Msg("[finalizeCommits] Waiting for Block Time")
time.Sleep(consensus.NextBlockDue.Sub(n))
}
// Send signal to Node to propose the new block for consensus
consensus.ReadySignal <- struct{}{}
// Update time due for next block
consensus.NextBlockDue = time.Now().Add(consensus.BlockPeriod)
}
// LastCommitSig returns the byte array of aggregated
// commit signature and bitmap of last block
func (consensus *Consensus) LastCommitSig() ([]byte, []byte, error) {
if consensus.blockNum <= 1 {
return nil, nil, nil
}
lastCommits, err := consensus.ChainReader.ReadLastCommits()
if err != nil ||
len(lastCommits) < shard.BLSSignatureSizeInBytes {
msgs := consensus.FBFTLog.GetMessagesByTypeSeq(
msg_pb.MessageType_COMMITTED, consensus.blockNum-1,
)
if len(msgs) != 1 {
consensus.getLogger().Error().
Int("numCommittedMsg", len(msgs)).
Msg("GetLastCommitSig failed with wrong number of committed message")
return nil, nil, errors.Errorf(
"GetLastCommitSig failed with wrong number of committed message %d", len(msgs),
)
}
lastCommits = msgs[0].Payload
}
//#### Read payload data from committed msg
aggSig := make([]byte, shard.BLSSignatureSizeInBytes)
bitmap := make([]byte, len(lastCommits)-shard.BLSSignatureSizeInBytes)
offset := 0
copy(aggSig[:], lastCommits[offset:offset+shard.BLSSignatureSizeInBytes])
offset += shard.BLSSignatureSizeInBytes
copy(bitmap[:], lastCommits[offset:])
//#### END Read payload data from committed msg
return aggSig, bitmap, nil
}
// try to catch up if fall behind
func (consensus *Consensus) tryCatchup() {
consensus.getLogger().Info().Msg("[TryCatchup] commit new blocks")
currentBlockNum := consensus.blockNum
for {
msgs := consensus.FBFTLog.GetMessagesByTypeSeq(
msg_pb.MessageType_COMMITTED, consensus.blockNum,
)
if len(msgs) == 0 {
break
}
if len(msgs) > 1 {
consensus.getLogger().Error().
Int("numMsgs", len(msgs)).
Msg("[TryCatchup] DANGER!!! we should only get one committed message for a given blockNum")
}
var committedMsg *FBFTMessage
var block *types.Block
for i := range msgs {
tmpBlock := consensus.FBFTLog.GetBlockByHash(msgs[i].BlockHash)
if tmpBlock == nil {
blksRepr, msgsRepr, incomingMsg :=
consensus.FBFTLog.Blocks().String(),
consensus.FBFTLog.Messages().String(),
msgs[i].String()
consensus.getLogger().Debug().
Str("FBFT-log-blocks", blksRepr).
Str("FBFT-log-messages", msgsRepr).
Str("incoming-message", incomingMsg).
Uint64("blockNum", msgs[i].BlockNum).
Uint64("viewID", msgs[i].ViewID).
Str("blockHash", msgs[i].BlockHash.Hex()).
Msg("[TryCatchup] Failed finding a matching block for committed message")
continue
}
if consensus.BlockVerifier == nil {
// do nothing
} else if err := consensus.BlockVerifier(tmpBlock); err != nil {
consensus.getLogger().Info().Msg("[TryCatchup] block verification failed")
continue
}
committedMsg = msgs[i]
block = tmpBlock
break
}
if block == nil || committedMsg == nil {
consensus.getLogger().Error().Msg("[TryCatchup] Failed finding a valid committed message.")
break
}
if block.ParentHash() != consensus.ChainReader.CurrentHeader().Hash() {
consensus.getLogger().Debug().Msg("[TryCatchup] parent block hash not match")
break
}
consensus.getLogger().Info().Msg("[TryCatchup] block found to commit")
preparedMsgs := consensus.FBFTLog.GetMessagesByTypeSeqHash(
msg_pb.MessageType_PREPARED, committedMsg.BlockNum, committedMsg.BlockHash,
)
msg := consensus.FBFTLog.FindMessageByMaxViewID(preparedMsgs)
if msg == nil {
break
}
consensus.getLogger().Info().Msg("[TryCatchup] prepared message found to commit")
// TODO(Chao): Explain the reasoning for these code
consensus.blockHash = [32]byte{}
consensus.blockNum = consensus.blockNum + 1
consensus.viewID = committedMsg.ViewID + 1
consensus.LeaderPubKey = committedMsg.SenderPubkey
consensus.getLogger().Info().Msg("[TryCatchup] Adding block to chain")
consensus.OnConsensusDone(block, committedMsg.Payload)
consensus.ResetState()
select {
case consensus.VerifiedNewBlock <- block:
default:
consensus.getLogger().Info().
Str("blockHash", block.Hash().String()).
Msg("[TryCatchup] consensus verified block send to chan failed")
continue
}
break
}
if currentBlockNum < consensus.blockNum {
consensus.getLogger().Info().
Uint64("From", currentBlockNum).
Uint64("To", consensus.blockNum).
Msg("[TryCatchup] Caught up!")
consensus.switchPhase(FBFTAnnounce, true)
}
// catup up and skip from view change trap
if currentBlockNum < consensus.blockNum &&
consensus.current.Mode() == ViewChanging {
consensus.current.SetMode(Normal)
consensus.consensusTimeout[timeoutViewChange].Stop()
}
// clean up old log
consensus.FBFTLog.DeleteBlocksLessThan(consensus.blockNum - 1)
consensus.FBFTLog.DeleteMessagesLessThan(consensus.blockNum - 1)
}
// Start waits for the next new block and run consensus
func (consensus *Consensus) Start(
blockChannel chan *types.Block, stopChan, stoppedChan, startChannel chan struct{},
) {
go func() {
toStart := false
isInitialLeader := consensus.IsLeader()
if isInitialLeader {
consensus.getLogger().Info().Time("time", time.Now()).Msg("[ConsensusMainLoop] Waiting for consensus start")
// send a signal to indicate it's ready to run consensus
// this signal is consumed by node object to create a new block and in turn trigger a new consensus on it
go func() {
<-startChannel
toStart = true
consensus.getLogger().Info().Time("time", time.Now()).Msg("[ConsensusMainLoop] Send ReadySignal")
consensus.ReadySignal <- struct{}{}
}()
}
consensus.getLogger().Info().Time("time", time.Now()).Msg("[ConsensusMainLoop] Consensus started")
defer close(stoppedChan)
ticker := time.NewTicker(3 * time.Second)
defer ticker.Stop()
consensus.consensusTimeout[timeoutBootstrap].Start()
consensus.getLogger().Debug().
Uint64("viewID", consensus.viewID).
Uint64("blockNum", consensus.blockNum).
Msg("[ConsensusMainLoop] Start bootstrap timeout (only once)")
vdfInProgress := false
// Set up next block due time.
consensus.NextBlockDue = time.Now().Add(consensus.BlockPeriod)
for {
select {
case <-ticker.C:
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] Ticker")
if !toStart && isInitialLeader {
continue
}
for k, v := range consensus.consensusTimeout {
if consensus.current.Mode() == Syncing ||
consensus.current.Mode() == Listening {
v.Stop()
}
if !v.CheckExpire() {
continue
}
if k != timeoutViewChange {
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] Ops Consensus Timeout!!!")
consensus.startViewChange(consensus.viewID + 1)
break
} else {
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] Ops View Change Timeout!!!")
viewID := consensus.current.ViewID()
consensus.startViewChange(viewID + 1)
break
}
}
case <-consensus.syncReadyChan:
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] syncReadyChan")
consensus.SetBlockNum(consensus.ChainReader.CurrentHeader().Number().Uint64() + 1)
consensus.SetViewID(consensus.ChainReader.CurrentHeader().ViewID().Uint64() + 1)
mode := consensus.UpdateConsensusInformation()
consensus.current.SetMode(mode)
consensus.getLogger().Info().Str("Mode", mode.String()).Msg("Node is IN SYNC")
case <-consensus.syncNotReadyChan:
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] syncNotReadyChan")
consensus.SetBlockNum(consensus.ChainReader.CurrentHeader().Number().Uint64() + 1)
consensus.current.SetMode(Syncing)
consensus.getLogger().Info().Msg("[ConsensusMainLoop] Node is OUT OF SYNC")
case newBlock := <-blockChannel:
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Msg("[ConsensusMainLoop] Received Proposed New Block!")
//VRF/VDF is only generated in the beacon chain
if consensus.NeedsRandomNumberGeneration(newBlock.Header().Epoch()) {
// generate VRF if the current block has a new leader
if !consensus.ChainReader.IsSameLeaderAsPreviousBlock(newBlock) {
vrfBlockNumbers, err := consensus.ChainReader.ReadEpochVrfBlockNums(newBlock.Header().Epoch())
if err != nil {
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Msg("[ConsensusMainLoop] no VRF block number from local db")
}
//check if VRF is already generated for the current block
vrfAlreadyGenerated := false
for _, v := range vrfBlockNumbers {
if v == newBlock.NumberU64() {
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Msg("[ConsensusMainLoop] VRF is already generated for this block")
vrfAlreadyGenerated = true
break
}
}
if !vrfAlreadyGenerated {
//generate a new VRF for the current block
vrfBlockNumbers := consensus.GenerateVrfAndProof(newBlock, vrfBlockNumbers)
//generate a new VDF for the current epoch if there are enough VRFs in the current epoch
//note that >= instead of == is used, because it is possible the current leader
//can commit this block, go offline without finishing VDF
if (!vdfInProgress) && len(vrfBlockNumbers) >= consensus.VdfSeedSize() {
//check local database to see if there's a VDF generated for this epoch
//generate a VDF if no blocknum is available
_, err := consensus.ChainReader.ReadEpochVdfBlockNum(newBlock.Header().Epoch())
if err != nil {
consensus.GenerateVdfAndProof(newBlock, vrfBlockNumbers)
vdfInProgress = true
}
}
}
}
vdfOutput, seed, err := consensus.GetNextRnd()
if err == nil {
vdfInProgress = false
// Verify the randomness
vdfObject := vdf_go.New(shard.Schedule.VdfDifficulty(), seed)
if !vdfObject.Verify(vdfOutput) {
consensus.getLogger().Warn().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Msg("[ConsensusMainLoop] failed to verify the VDF output")
} else {
//write the VDF only if VDF has not been generated
_, err := consensus.ChainReader.ReadEpochVdfBlockNum(newBlock.Header().Epoch())
if err == nil {
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Msg("[ConsensusMainLoop] VDF has already been generated previously")
} else {
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Msg("[ConsensusMainLoop] Generated a new VDF")
newBlock.AddVdf(vdfOutput[:])
}
}
}
}
startTime = time.Now()
consensus.msgSender.Reset(newBlock.NumberU64())
consensus.getLogger().Debug().
Int("numTxs", len(newBlock.Transactions())).
Int("numStakingTxs", len(newBlock.StakingTransactions())).
Time("startTime", startTime).
Int64("publicKeys", consensus.Decider.ParticipantsCount()).
Msg("[ConsensusMainLoop] STARTING CONSENSUS")
consensus.announce(newBlock)
case msg := <-consensus.MsgChan:
consensus.handleMessageUpdate(msg)
case viewID := <-consensus.commitFinishChan:
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] commitFinishChan")
// Only Leader execute this condition
func() {
consensus.mutex.Lock()
defer consensus.mutex.Unlock()
if viewID == consensus.viewID {
consensus.finalizeCommits()
}
}()
case <-stopChan:
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] stopChan")
return
}
}
consensus.getLogger().Debug().Msg("[ConsensusMainLoop] Ended.")
}()
}
// GenerateVrfAndProof generates new VRF/Proof from hash of previous block
func (consensus *Consensus) GenerateVrfAndProof(newBlock *types.Block, vrfBlockNumbers []uint64) []uint64 {
key, err := consensus.GetConsensusLeaderPrivateKey()
if err != nil {
consensus.getLogger().Error().
Err(err).
Msg("[GenerateVrfAndProof] VRF generation error")
return vrfBlockNumbers
}
sk := vrf_bls.NewVRFSigner(key)
blockHash := [32]byte{}
previousHeader := consensus.ChainReader.GetHeaderByNumber(
newBlock.NumberU64() - 1,
)
previousHash := previousHeader.Hash()
copy(blockHash[:], previousHash[:])
vrf, proof := sk.Evaluate(blockHash[:])
newBlock.AddVrf(append(vrf[:], proof...))
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Int("Num of VRF", len(vrfBlockNumbers)).
Msg("[ConsensusMainLoop] Leader generated a VRF")
return vrfBlockNumbers
}
// ValidateVrfAndProof validates a VRF/Proof from hash of previous block
func (consensus *Consensus) ValidateVrfAndProof(headerObj *block.Header) bool {
vrfPk := vrf_bls.NewVRFVerifier(consensus.LeaderPubKey)
var blockHash [32]byte
previousHeader := consensus.ChainReader.GetHeaderByNumber(
headerObj.Number().Uint64() - 1,
)
previousHash := previousHeader.Hash()
copy(blockHash[:], previousHash[:])
vrfProof := [96]byte{}
copy(vrfProof[:], headerObj.Vrf()[32:])
hash, err := vrfPk.ProofToHash(blockHash[:], vrfProof[:])
if err != nil {
consensus.getLogger().Warn().
Err(err).
Str("MsgBlockNum", headerObj.Number().String()).
Msg("[OnAnnounce] VRF verification error")
return false
}
if !bytes.Equal(hash[:], headerObj.Vrf()[:32]) {
consensus.getLogger().Warn().
Str("MsgBlockNum", headerObj.Number().String()).
Msg("[OnAnnounce] VRF proof is not valid")
return false
}
vrfBlockNumbers, _ := consensus.ChainReader.ReadEpochVrfBlockNums(
headerObj.Epoch(),
)
consensus.getLogger().Info().
Str("MsgBlockNum", headerObj.Number().String()).
Int("Number of VRF", len(vrfBlockNumbers)).
Msg("[OnAnnounce] validated a new VRF")
return true
}
// GenerateVdfAndProof generates new VDF/Proof from VRFs in the current epoch
func (consensus *Consensus) GenerateVdfAndProof(newBlock *types.Block, vrfBlockNumbers []uint64) {
//derive VDF seed from VRFs generated in the current epoch
seed := [32]byte{}
for i := 0; i < consensus.VdfSeedSize(); i++ {
previousVrf := consensus.ChainReader.GetVrfByNumber(vrfBlockNumbers[i])
for j := 0; j < len(seed); j++ {
seed[j] = seed[j] ^ previousVrf[j]
}
}
consensus.getLogger().Info().
Uint64("MsgBlockNum", newBlock.NumberU64()).
Uint64("Epoch", newBlock.Header().Epoch().Uint64()).
Int("Num of VRF", len(vrfBlockNumbers)).
Msg("[ConsensusMainLoop] VDF computation started")
// TODO ek – limit concurrency
go func() {
vdf := vdf_go.New(shard.Schedule.VdfDifficulty(), seed)
outputChannel := vdf.GetOutputChannel()
start := time.Now()
vdf.Execute()
duration := time.Since(start)
consensus.getLogger().Info().
Dur("duration", duration).
Msg("[ConsensusMainLoop] VDF computation finished")
output := <-outputChannel
// The first 516 bytes are the VDF+proof and the last 32 bytes are XORed VRF as seed
rndBytes := [548]byte{}
copy(rndBytes[:516], output[:])
copy(rndBytes[516:], seed[:])
consensus.RndChannel <- rndBytes
}()
}
// ValidateVdfAndProof validates the VDF/proof in the current epoch
func (consensus *Consensus) ValidateVdfAndProof(headerObj *block.Header) bool {
vrfBlockNumbers, err := consensus.ChainReader.ReadEpochVrfBlockNums(headerObj.Epoch())
if err != nil {
consensus.getLogger().Error().Err(err).
Str("MsgBlockNum", headerObj.Number().String()).
Msg("[OnAnnounce] failed to read VRF block numbers for VDF computation")
}
//extra check to make sure there's no index out of range error
//it can happen if epoch is messed up, i.e. VDF ouput is generated in the next epoch
if consensus.VdfSeedSize() > len(vrfBlockNumbers) {
return false
}
seed := [32]byte{}
for i := 0; i < consensus.VdfSeedSize(); i++ {
previousVrf := consensus.ChainReader.GetVrfByNumber(vrfBlockNumbers[i])
for j := 0; j < len(seed); j++ {
seed[j] = seed[j] ^ previousVrf[j]
}
}
vdfObject := vdf_go.New(shard.Schedule.VdfDifficulty(), seed)
vdfOutput := [516]byte{}
copy(vdfOutput[:], headerObj.Vdf())
if vdfObject.Verify(vdfOutput) {
consensus.getLogger().Info().
Str("MsgBlockNum", headerObj.Number().String()).
Int("Num of VRF", consensus.VdfSeedSize()).
Msg("[OnAnnounce] validated a new VDF")
} else {
consensus.getLogger().Warn().
Str("MsgBlockNum", headerObj.Number().String()).
Uint64("Epoch", headerObj.Epoch().Uint64()).
Int("Num of VRF", consensus.VdfSeedSize()).
Msg("[OnAnnounce] VDF proof is not valid")
return false
}
return true
}