prysm-pulse/beacon-chain/sync/validate_beacon_blocks.go
2021-05-26 11:33:46 -07:00

266 lines
9.6 KiB
Go

package sync
import (
"context"
"errors"
"fmt"
"time"
"github.com/libp2p/go-libp2p-core/peer"
pubsub "github.com/libp2p/go-libp2p-pubsub"
types "github.com/prysmaticlabs/eth2-types"
ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
"github.com/prysmaticlabs/prysm/beacon-chain/core/blocks"
"github.com/prysmaticlabs/prysm/beacon-chain/core/feed"
blockfeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/block"
"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
"github.com/prysmaticlabs/prysm/beacon-chain/core/state"
"github.com/prysmaticlabs/prysm/shared/bytesutil"
"github.com/prysmaticlabs/prysm/shared/interfaces"
"github.com/prysmaticlabs/prysm/shared/params"
"github.com/prysmaticlabs/prysm/shared/timeutils"
"github.com/prysmaticlabs/prysm/shared/traceutil"
"github.com/sirupsen/logrus"
"go.opencensus.io/trace"
)
// validateBeaconBlockPubSub checks that the incoming block has a valid BLS signature.
// Blocks that have already been seen are ignored. If the BLS signature is any valid signature,
// this method rebroadcasts the message.
func (s *Service) validateBeaconBlockPubSub(ctx context.Context, pid peer.ID, msg *pubsub.Message) pubsub.ValidationResult {
receivedTime := timeutils.Now()
// Validation runs on publish (not just subscriptions), so we should approve any message from
// ourselves.
if pid == s.cfg.P2P.PeerID() {
return pubsub.ValidationAccept
}
// We should not attempt to process blocks until fully synced, but propagation is OK.
if s.cfg.InitialSync.Syncing() {
return pubsub.ValidationIgnore
}
ctx, span := trace.StartSpan(ctx, "sync.validateBeaconBlockPubSub")
defer span.End()
m, err := s.decodePubsubMessage(msg)
if err != nil {
log.WithError(err).Debug("Could not decode message")
traceutil.AnnotateError(span, err)
return pubsub.ValidationReject
}
s.validateBlockLock.Lock()
defer s.validateBlockLock.Unlock()
rblk, ok := m.(*ethpb.SignedBeaconBlock)
if !ok {
log.WithError(errors.New("msg is not ethpb.SignedBeaconBlock")).Debug("Rejected block")
return pubsub.ValidationReject
}
blk := interfaces.WrappedPhase0SignedBeaconBlock(rblk)
if blk.IsNil() || blk.Block().IsNil() {
log.WithError(errors.New("block.Block is nil")).Debug("Rejected block")
return pubsub.ValidationReject
}
// Broadcast the block on a feed to notify other services in the beacon node
// of a received block (even if it does not process correctly through a state transition).
s.cfg.BlockNotifier.BlockFeed().Send(&feed.Event{
Type: blockfeed.ReceivedBlock,
Data: &blockfeed.ReceivedBlockData{
SignedBlock: blk,
},
})
// Verify the block is the first block received for the proposer for the slot.
if s.hasSeenBlockIndexSlot(blk.Block().Slot(), blk.Block().ProposerIndex()) {
return pubsub.ValidationIgnore
}
blockRoot, err := blk.Block().HashTreeRoot()
if err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
if s.cfg.DB.HasBlock(ctx, blockRoot) {
return pubsub.ValidationIgnore
}
// Check if parent is a bad block and then reject the block.
if s.hasBadBlock(bytesutil.ToBytes32(blk.Block().ParentRoot())) {
s.setBadBlock(ctx, blockRoot)
e := fmt.Errorf("received block with root %#x that has an invalid parent %#x", blockRoot, blk.Block().ParentRoot())
log.WithError(e).WithField("blockSlot", blk.Block().Slot()).Debug("Rejected block")
return pubsub.ValidationReject
}
s.pendingQueueLock.RLock()
if s.seenPendingBlocks[blockRoot] {
s.pendingQueueLock.RUnlock()
return pubsub.ValidationIgnore
}
s.pendingQueueLock.RUnlock()
if err := helpers.VerifySlotTime(uint64(s.cfg.Chain.GenesisTime().Unix()), blk.Block().Slot(), params.BeaconNetworkConfig().MaximumGossipClockDisparity); err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
// Add metrics for block arrival time subtracts slot start time.
genesisTime := uint64(s.cfg.Chain.GenesisTime().Unix())
if err := captureArrivalTimeMetric(genesisTime, blk.Block().Slot()); err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
startSlot, err := helpers.StartSlot(s.cfg.Chain.FinalizedCheckpt().Epoch)
if err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
if startSlot >= blk.Block().Slot() {
e := fmt.Errorf("finalized slot %d greater or equal to block slot %d", startSlot, blk.Block().Slot())
log.WithError(e).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
// Handle block when the parent is unknown.
if !s.cfg.DB.HasBlock(ctx, bytesutil.ToBytes32(blk.Block().ParentRoot())) {
s.pendingQueueLock.Lock()
if err := s.insertBlockToPendingQueue(blk.Block().Slot(), blk, blockRoot); err != nil {
s.pendingQueueLock.Unlock()
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
s.pendingQueueLock.Unlock()
log.WithError(errors.New("unknown parent")).WithField("blockSlot", blk.Block().Slot()).Debug("Ignored block")
return pubsub.ValidationIgnore
}
if err := s.validateBeaconBlock(ctx, blk, blockRoot); err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Warn("Rejected block")
return pubsub.ValidationReject
}
// Record attribute of valid block.
span.AddAttributes(trace.Int64Attribute("slotInEpoch", int64(blk.Block().Slot()%params.BeaconConfig().SlotsPerEpoch)))
msg.ValidatorData = rblk // Used in downstream subscriber
// Log the arrival time of the accepted block
startTime, err := helpers.SlotToTime(genesisTime, blk.Block().Slot())
if err != nil {
log.WithError(err).WithField("blockSlot", blk.Block().Slot()).Debug("Couldn't get slot start time")
return pubsub.ValidationIgnore
}
log.WithFields(logrus.Fields{
"blockSlot": blk.Block().Slot(),
"sinceSlotStartTime": receivedTime.Sub(startTime),
}).Debug("Received block")
return pubsub.ValidationAccept
}
func (s *Service) validateBeaconBlock(ctx context.Context, blk interfaces.SignedBeaconBlock, blockRoot [32]byte) error {
ctx, span := trace.StartSpan(ctx, "sync.validateBeaconBlock")
defer span.End()
if err := s.cfg.Chain.VerifyBlkDescendant(ctx, bytesutil.ToBytes32(blk.Block().ParentRoot())); err != nil {
s.setBadBlock(ctx, blockRoot)
return err
}
hasStateSummaryDB := s.cfg.DB.HasStateSummary(ctx, bytesutil.ToBytes32(blk.Block().ParentRoot()))
if !hasStateSummaryDB {
_, err := s.cfg.StateGen.RecoverStateSummary(ctx, bytesutil.ToBytes32(blk.Block().ParentRoot()))
if err != nil {
return err
}
}
parentState, err := s.cfg.StateGen.StateByRoot(ctx, bytesutil.ToBytes32(blk.Block().ParentRoot()))
if err != nil {
return err
}
if err := blocks.VerifyBlockSignature(parentState, blk.Block().ProposerIndex(), blk.Signature(), blk.Block().HashTreeRoot); err != nil {
s.setBadBlock(ctx, blockRoot)
return err
}
// There is an epoch lookahead for validator proposals
// for the next epoch from the start of our current epoch. We
// use the randao mix at the end of the previous epoch as the seed
// to determine proposals.
// Seed for Next Epoch => Derived From Randao Mix at the end of the Previous Epoch.
// Which is why we simply set the slot over here.
nextEpoch := helpers.NextEpoch(parentState)
expectedEpoch := helpers.SlotToEpoch(blk.Block().Slot())
if expectedEpoch <= nextEpoch {
err = parentState.SetSlot(blk.Block().Slot())
if err != nil {
return err
}
} else {
// In the event the block is more than an epoch ahead from its
// parent state, we have to advance the state forward.
parentState, err = state.ProcessSlots(ctx, parentState, blk.Block().Slot())
if err != nil {
return err
}
}
idx, err := helpers.BeaconProposerIndex(parentState)
if err != nil {
return err
}
if blk.Block().ProposerIndex() != idx {
s.setBadBlock(ctx, blockRoot)
return errors.New("incorrect proposer index")
}
return nil
}
// Returns true if the block is not the first block proposed for the proposer for the slot.
func (s *Service) hasSeenBlockIndexSlot(slot types.Slot, proposerIdx types.ValidatorIndex) bool {
s.seenBlockLock.RLock()
defer s.seenBlockLock.RUnlock()
b := append(bytesutil.Bytes32(uint64(slot)), bytesutil.Bytes32(uint64(proposerIdx))...)
_, seen := s.seenBlockCache.Get(string(b))
return seen
}
// Set block proposer index and slot as seen for incoming blocks.
func (s *Service) setSeenBlockIndexSlot(slot types.Slot, proposerIdx types.ValidatorIndex) {
s.seenBlockLock.Lock()
defer s.seenBlockLock.Unlock()
b := append(bytesutil.Bytes32(uint64(slot)), bytesutil.Bytes32(uint64(proposerIdx))...)
s.seenBlockCache.Add(string(b), true)
}
// Returns true if the block is marked as a bad block.
func (s *Service) hasBadBlock(root [32]byte) bool {
s.badBlockLock.RLock()
defer s.badBlockLock.RUnlock()
_, seen := s.badBlockCache.Get(string(root[:]))
return seen
}
// Set bad block in the cache.
func (s *Service) setBadBlock(ctx context.Context, root [32]byte) {
s.badBlockLock.Lock()
defer s.badBlockLock.Unlock()
if ctx.Err() != nil { // Do not mark block as bad if it was due to context error.
return
}
s.badBlockCache.Add(string(root[:]), true)
}
// This captures metrics for block arrival time by subtracts slot start time.
func captureArrivalTimeMetric(genesisTime uint64, currentSlot types.Slot) error {
startTime, err := helpers.SlotToTime(genesisTime, currentSlot)
if err != nil {
return err
}
ms := timeutils.Now().Sub(startTime) / time.Millisecond
arrivalBlockPropagationHistogram.Observe(float64(ms))
return nil
}