|
package evidence
|
|
|
|
import (
|
|
"fmt"
|
|
"sync"
|
|
"time"
|
|
|
|
dbm "github.com/tendermint/tm-db"
|
|
|
|
clist "github.com/tendermint/tendermint/libs/clist"
|
|
"github.com/tendermint/tendermint/libs/log"
|
|
sm "github.com/tendermint/tendermint/state"
|
|
"github.com/tendermint/tendermint/store"
|
|
"github.com/tendermint/tendermint/types"
|
|
)
|
|
|
|
const (
|
|
baseKeyCommitted = byte(0x00)
|
|
baseKeyPending = byte(0x01)
|
|
baseKeyPOLC = byte(0x02)
|
|
)
|
|
|
|
// Pool maintains a pool of valid evidence to be broadcasted and committed
|
|
type Pool struct {
|
|
logger log.Logger
|
|
|
|
evidenceStore dbm.DB
|
|
evidenceList *clist.CList // concurrent linked-list of evidence
|
|
|
|
// needed to load validators to verify evidence
|
|
stateDB dbm.DB
|
|
// needed to load headers to verify evidence
|
|
blockStore *store.BlockStore
|
|
|
|
mtx sync.Mutex
|
|
// latest state
|
|
state sm.State
|
|
// a map of active validators and respective last heights validator is active
|
|
// if it was in validator set after EvidenceParams.MaxAgeNumBlocks or
|
|
// currently is (ie. [MaxAgeNumBlocks, CurrentHeight])
|
|
// In simple words, it means it's still bonded -> therefore slashable.
|
|
valToLastHeight valToLastHeightMap
|
|
}
|
|
|
|
// Validator.Address -> Last height it was in validator set
|
|
type valToLastHeightMap map[string]int64
|
|
|
|
func NewPool(stateDB, evidenceDB dbm.DB, blockStore *store.BlockStore) (*Pool, error) {
|
|
var (
|
|
state = sm.LoadState(stateDB)
|
|
)
|
|
|
|
valToLastHeight, err := buildValToLastHeightMap(state, stateDB, blockStore)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
pool := &Pool{
|
|
stateDB: stateDB,
|
|
blockStore: blockStore,
|
|
state: state,
|
|
logger: log.NewNopLogger(),
|
|
evidenceStore: evidenceDB,
|
|
evidenceList: clist.New(),
|
|
valToLastHeight: valToLastHeight,
|
|
}
|
|
|
|
// if pending evidence already in db, in event of prior failure, then load it back to the evidenceList
|
|
evList := pool.AllPendingEvidence()
|
|
for _, ev := range evList {
|
|
if pool.IsEvidenceExpired(ev) {
|
|
pool.removePendingEvidence(ev)
|
|
continue
|
|
}
|
|
pool.evidenceList.PushBack(ev)
|
|
}
|
|
|
|
return pool, nil
|
|
}
|
|
|
|
// PendingEvidence is used primarily as part of block proposal and returns up to maxNum of uncommitted evidence.
|
|
// If maxNum is -1, all evidence is returned. Pending evidence is prioritised based on time.
|
|
func (evpool *Pool) PendingEvidence(maxNum uint32) []types.Evidence {
|
|
evidence, err := evpool.listEvidence(baseKeyPending, int64(maxNum))
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to retrieve pending evidence", "err", err)
|
|
}
|
|
return evidence
|
|
}
|
|
|
|
func (evpool *Pool) AllPendingEvidence() []types.Evidence {
|
|
evidence, err := evpool.listEvidence(baseKeyPending, -1)
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to retrieve pending evidence", "err", err)
|
|
}
|
|
return evidence
|
|
}
|
|
|
|
// Update uses the latest block & state to update its copy of the state,
|
|
// validator to last height map and calls MarkEvidenceAsCommitted.
|
|
func (evpool *Pool) Update(block *types.Block, state sm.State) {
|
|
// sanity check
|
|
if state.LastBlockHeight != block.Height {
|
|
panic(
|
|
fmt.Sprintf("Failed EvidencePool.Update sanity check: got state.Height=%d with block.Height=%d",
|
|
state.LastBlockHeight,
|
|
block.Height,
|
|
),
|
|
)
|
|
}
|
|
|
|
// remove evidence from pending and mark committed
|
|
evpool.MarkEvidenceAsCommitted(block.Height, block.Time, block.Evidence.Evidence)
|
|
|
|
// remove expired evidence - this should be done at every height to ensure we don't send expired evidence to peers
|
|
evpool.removeExpiredPendingEvidence()
|
|
|
|
// as it's not vital to remove expired POLCs, we only prune periodically
|
|
if block.Height%state.ConsensusParams.Evidence.MaxAgeNumBlocks == 0 {
|
|
evpool.pruneExpiredPOLC()
|
|
}
|
|
|
|
// update the state
|
|
evpool.mtx.Lock()
|
|
defer evpool.mtx.Unlock()
|
|
evpool.state = state
|
|
evpool.updateValToLastHeight(block.Height, state)
|
|
}
|
|
|
|
// AddPOLC adds a proof of lock change to the evidence database
|
|
// that may be needed in the future to verify votes
|
|
func (evpool *Pool) AddPOLC(polc types.ProofOfLockChange) error {
|
|
key := keyPOLC(polc)
|
|
polcBytes := cdc.MustMarshalBinaryBare(polc)
|
|
return evpool.evidenceStore.Set(key, polcBytes)
|
|
}
|
|
|
|
// AddEvidence checks the evidence is valid and adds it to the pool. If
|
|
// evidence is composite (ConflictingHeadersEvidence), it will be broken up
|
|
// into smaller pieces.
|
|
func (evpool *Pool) AddEvidence(evidence types.Evidence) error {
|
|
var (
|
|
state = evpool.State()
|
|
evList = []types.Evidence{evidence}
|
|
)
|
|
|
|
valSet, err := sm.LoadValidators(evpool.stateDB, evidence.Height())
|
|
if err != nil {
|
|
return fmt.Errorf("can't load validators at height #%d: %w", evidence.Height(), err)
|
|
}
|
|
|
|
// Break composite evidence into smaller pieces.
|
|
if ce, ok := evidence.(types.CompositeEvidence); ok {
|
|
evpool.logger.Info("Breaking up composite evidence", "ev", evidence)
|
|
|
|
blockMeta := evpool.blockStore.LoadBlockMeta(evidence.Height())
|
|
if blockMeta == nil {
|
|
return fmt.Errorf("don't have block meta at height #%d", evidence.Height())
|
|
}
|
|
|
|
if err := ce.VerifyComposite(&blockMeta.Header, valSet); err != nil {
|
|
return err
|
|
}
|
|
|
|
// XXX: Copy here since this should be a rare case.
|
|
evpool.mtx.Lock()
|
|
valToLastHeightCopy := make(valToLastHeightMap, len(evpool.valToLastHeight))
|
|
for k, v := range evpool.valToLastHeight {
|
|
valToLastHeightCopy[k] = v
|
|
}
|
|
evpool.mtx.Unlock()
|
|
|
|
evList = ce.Split(&blockMeta.Header, valSet, valToLastHeightCopy)
|
|
}
|
|
|
|
for _, ev := range evList {
|
|
if evpool.Has(ev) {
|
|
continue
|
|
}
|
|
|
|
// For lunatic validator evidence, a header needs to be fetched.
|
|
var header *types.Header
|
|
if _, ok := ev.(*types.LunaticValidatorEvidence); ok {
|
|
header = evpool.Header(ev.Height())
|
|
if header == nil {
|
|
return fmt.Errorf("don't have block meta at height #%d", ev.Height())
|
|
}
|
|
}
|
|
|
|
// 1) Verify against state.
|
|
if err := sm.VerifyEvidence(evpool.stateDB, state, ev, header); err != nil {
|
|
return fmt.Errorf("failed to verify %v: %w", ev, err)
|
|
}
|
|
|
|
// 2) Save to store.
|
|
if err := evpool.addPendingEvidence(ev); err != nil {
|
|
return fmt.Errorf("database error: %v", err)
|
|
}
|
|
|
|
// 3) Add evidence to clist.
|
|
evpool.evidenceList.PushBack(ev)
|
|
|
|
evpool.logger.Info("Verified new evidence of byzantine behaviour", "evidence", ev)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// MarkEvidenceAsCommitted marks all the evidence as committed and removes it
|
|
// from the queue.
|
|
func (evpool *Pool) MarkEvidenceAsCommitted(height int64, lastBlockTime time.Time, evidence []types.Evidence) {
|
|
// make a map of committed evidence to remove from the clist
|
|
blockEvidenceMap := make(map[string]struct{})
|
|
for _, ev := range evidence {
|
|
// As the evidence is stored in the block store we only need to record the height that it was saved at.
|
|
key := keyCommitted(ev)
|
|
evBytes := cdc.MustMarshalBinaryBare(height)
|
|
if err := evpool.evidenceStore.Set(key, evBytes); err != nil {
|
|
evpool.logger.Error("Unable to add committed evidence", "err", err)
|
|
// if we can't move evidence to committed then don't remove the evidence from pending
|
|
continue
|
|
}
|
|
// if pending, remove from that bucket, remember not all evidence has been seen before
|
|
if evpool.IsPending(ev) {
|
|
evpool.removePendingEvidence(ev)
|
|
blockEvidenceMap[evMapKey(ev)] = struct{}{}
|
|
}
|
|
}
|
|
|
|
// remove committed evidence from the clist
|
|
if len(blockEvidenceMap) != 0 {
|
|
evpool.removeEvidenceFromList(blockEvidenceMap)
|
|
}
|
|
}
|
|
|
|
// Has checks whether the evidence exists either pending or already committed
|
|
func (evpool *Pool) Has(evidence types.Evidence) bool {
|
|
return evpool.IsPending(evidence) || evpool.IsCommitted(evidence)
|
|
}
|
|
|
|
// IsEvidenceExpired checks whether evidence is past the maximum age where it can be used
|
|
func (evpool *Pool) IsEvidenceExpired(evidence types.Evidence) bool {
|
|
return evpool.IsExpired(evidence.Height(), evidence.Time())
|
|
}
|
|
|
|
// IsExpired checks whether evidence or a polc is expired by checking whether a height and time is older
|
|
// than set by the evidence consensus parameters
|
|
func (evpool *Pool) IsExpired(height int64, time time.Time) bool {
|
|
var (
|
|
params = evpool.State().ConsensusParams.Evidence
|
|
ageDuration = evpool.State().LastBlockTime.Sub(time)
|
|
ageNumBlocks = evpool.State().LastBlockHeight - height
|
|
)
|
|
return ageNumBlocks > params.MaxAgeNumBlocks &&
|
|
ageDuration > params.MaxAgeDuration
|
|
}
|
|
|
|
// IsCommitted returns true if we have already seen this exact evidence and it is already marked as committed.
|
|
func (evpool *Pool) IsCommitted(evidence types.Evidence) bool {
|
|
key := keyCommitted(evidence)
|
|
ok, err := evpool.evidenceStore.Has(key)
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to find committed evidence", "err", err)
|
|
}
|
|
return ok
|
|
}
|
|
|
|
// IsPending checks whether the evidence is already pending. DB errors are passed to the logger.
|
|
func (evpool *Pool) IsPending(evidence types.Evidence) bool {
|
|
key := keyPending(evidence)
|
|
ok, err := evpool.evidenceStore.Has(key)
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to find pending evidence", "err", err)
|
|
}
|
|
return ok
|
|
}
|
|
|
|
// RetrievePOLC attempts to find a polc at the given height and round, if not there it returns an error
|
|
func (evpool *Pool) RetrievePOLC(height int64, round int) (types.ProofOfLockChange, error) {
|
|
var polc types.ProofOfLockChange
|
|
key := keyPOLCFromHeightAndRound(height, round)
|
|
polcBytes, err := evpool.evidenceStore.Get(key)
|
|
if err != nil {
|
|
return polc, err
|
|
}
|
|
if polcBytes == nil {
|
|
return polc, fmt.Errorf("unable to find polc at height %d and round %d", height, round)
|
|
}
|
|
err = cdc.UnmarshalBinaryBare(polcBytes, &polc)
|
|
return polc, err
|
|
}
|
|
|
|
// EvidenceFront goes to the first evidence in the clist
|
|
func (evpool *Pool) EvidenceFront() *clist.CElement {
|
|
return evpool.evidenceList.Front()
|
|
}
|
|
|
|
// EvidenceWaitChan is a channel that closes once the first evidence in the list is there. i.e Front is not nil
|
|
func (evpool *Pool) EvidenceWaitChan() <-chan struct{} {
|
|
return evpool.evidenceList.WaitChan()
|
|
}
|
|
|
|
// SetLogger sets the Logger.
|
|
func (evpool *Pool) SetLogger(l log.Logger) {
|
|
evpool.logger = l
|
|
}
|
|
|
|
// Header gets the header from the block store at a specified height.
|
|
// Is used for validation of LunaticValidatorEvidence
|
|
func (evpool *Pool) Header(height int64) *types.Header {
|
|
blockMeta := evpool.blockStore.LoadBlockMeta(height)
|
|
if blockMeta == nil {
|
|
return nil
|
|
}
|
|
return &blockMeta.Header
|
|
}
|
|
|
|
// ValidatorLastHeight returns the last height of the validator w/ the
|
|
// given address. 0 - if address never was a validator or was such a
|
|
// long time ago (> ConsensusParams.Evidence.MaxAgeDuration && >
|
|
// ConsensusParams.Evidence.MaxAgeNumBlocks).
|
|
func (evpool *Pool) ValidatorLastHeight(address []byte) int64 {
|
|
evpool.mtx.Lock()
|
|
defer evpool.mtx.Unlock()
|
|
|
|
h, ok := evpool.valToLastHeight[string(address)]
|
|
if !ok {
|
|
return 0
|
|
}
|
|
return h
|
|
}
|
|
|
|
// State returns the current state of the evpool.
|
|
func (evpool *Pool) State() sm.State {
|
|
evpool.mtx.Lock()
|
|
defer evpool.mtx.Unlock()
|
|
return evpool.state
|
|
}
|
|
|
|
func (evpool *Pool) addPendingEvidence(evidence types.Evidence) error {
|
|
evBytes := cdc.MustMarshalBinaryBare(evidence)
|
|
key := keyPending(evidence)
|
|
return evpool.evidenceStore.Set(key, evBytes)
|
|
}
|
|
|
|
func (evpool *Pool) removePendingEvidence(evidence types.Evidence) {
|
|
key := keyPending(evidence)
|
|
if err := evpool.evidenceStore.Delete(key); err != nil {
|
|
evpool.logger.Error("Unable to delete pending evidence", "err", err)
|
|
} else {
|
|
evpool.logger.Info("Deleted pending evidence", "evidence", evidence)
|
|
}
|
|
}
|
|
|
|
// listEvidence lists up to maxNum pieces of evidence for the given prefix key.
|
|
// If maxNum is -1, there's no cap on the size of returned evidence.
|
|
func (evpool *Pool) listEvidence(prefixKey byte, maxNum int64) ([]types.Evidence, error) {
|
|
var count int64
|
|
var evidence []types.Evidence
|
|
iter, err := dbm.IteratePrefix(evpool.evidenceStore, []byte{prefixKey})
|
|
if err != nil {
|
|
return nil, fmt.Errorf("database error: %v", err)
|
|
}
|
|
defer iter.Close()
|
|
for ; iter.Valid(); iter.Next() {
|
|
val := iter.Value()
|
|
|
|
if count == maxNum {
|
|
return evidence, nil
|
|
}
|
|
count++
|
|
|
|
var ev types.Evidence
|
|
err := cdc.UnmarshalBinaryBare(val, &ev)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
evidence = append(evidence, ev)
|
|
}
|
|
return evidence, nil
|
|
}
|
|
|
|
func (evpool *Pool) removeExpiredPendingEvidence() {
|
|
iter, err := dbm.IteratePrefix(evpool.evidenceStore, []byte{baseKeyPending})
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to iterate over pending evidence", "err", err)
|
|
return
|
|
}
|
|
defer iter.Close()
|
|
blockEvidenceMap := make(map[string]struct{})
|
|
for ; iter.Valid(); iter.Next() {
|
|
evBytes := iter.Value()
|
|
var ev types.Evidence
|
|
err := cdc.UnmarshalBinaryBare(evBytes, &ev)
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to unmarshal POLC", "err", err)
|
|
continue
|
|
}
|
|
if !evpool.IsExpired(ev.Height()-1, ev.Time()) {
|
|
if len(blockEvidenceMap) != 0 {
|
|
evpool.removeEvidenceFromList(blockEvidenceMap)
|
|
}
|
|
return
|
|
}
|
|
evpool.removePendingEvidence(ev)
|
|
blockEvidenceMap[evMapKey(ev)] = struct{}{}
|
|
}
|
|
}
|
|
|
|
func (evpool *Pool) removeEvidenceFromList(
|
|
blockEvidenceMap map[string]struct{}) {
|
|
|
|
for e := evpool.evidenceList.Front(); e != nil; e = e.Next() {
|
|
// Remove from clist
|
|
ev := e.Value.(types.Evidence)
|
|
if _, ok := blockEvidenceMap[evMapKey(ev)]; ok {
|
|
evpool.evidenceList.Remove(e)
|
|
e.DetachPrev()
|
|
}
|
|
}
|
|
}
|
|
|
|
func (evpool *Pool) pruneExpiredPOLC() {
|
|
evpool.logger.Debug("Pruning expired POLC's")
|
|
iter, err := dbm.IteratePrefix(evpool.evidenceStore, []byte{baseKeyPOLC})
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to iterate over POLC's", "err", err)
|
|
return
|
|
}
|
|
defer iter.Close()
|
|
for ; iter.Valid(); iter.Next() {
|
|
proofBytes := iter.Value()
|
|
var proof types.ProofOfLockChange
|
|
err := cdc.UnmarshalBinaryBare(proofBytes, &proof)
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to unmarshal POLC", "err", err)
|
|
continue
|
|
}
|
|
if !evpool.IsExpired(proof.Height()-1, proof.Time()) {
|
|
return
|
|
}
|
|
err = evpool.evidenceStore.Delete(iter.Key())
|
|
if err != nil {
|
|
evpool.logger.Error("Unable to delete expired POLC", "err", err)
|
|
continue
|
|
}
|
|
evpool.logger.Info("Deleted expired POLC", "polc", proof)
|
|
}
|
|
}
|
|
|
|
func evMapKey(ev types.Evidence) string {
|
|
return string(ev.Hash())
|
|
}
|
|
|
|
func (evpool *Pool) updateValToLastHeight(blockHeight int64, state sm.State) {
|
|
// Update current validators & add new ones.
|
|
for _, val := range state.Validators.Validators {
|
|
evpool.valToLastHeight[string(val.Address)] = blockHeight
|
|
}
|
|
|
|
// Remove validators outside of MaxAgeNumBlocks & MaxAgeDuration.
|
|
removeHeight := blockHeight - state.ConsensusParams.Evidence.MaxAgeNumBlocks
|
|
if removeHeight >= 1 {
|
|
for val, height := range evpool.valToLastHeight {
|
|
if height <= removeHeight {
|
|
delete(evpool.valToLastHeight, val)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func buildValToLastHeightMap(state sm.State, stateDB dbm.DB, blockStore *store.BlockStore) (valToLastHeightMap, error) {
|
|
var (
|
|
valToLastHeight = make(map[string]int64)
|
|
params = state.ConsensusParams.Evidence
|
|
|
|
numBlocks = int64(0)
|
|
minAgeTime = time.Now().Add(-params.MaxAgeDuration)
|
|
height = state.LastBlockHeight
|
|
)
|
|
|
|
if height == 0 {
|
|
return valToLastHeight, nil
|
|
}
|
|
|
|
meta := blockStore.LoadBlockMeta(height)
|
|
if meta == nil {
|
|
return nil, fmt.Errorf("block meta for height %d not found", height)
|
|
}
|
|
blockTime := meta.Header.Time
|
|
|
|
// From state.LastBlockHeight, build a map of "active" validators until
|
|
// MaxAgeNumBlocks is passed and block time is less than now() -
|
|
// MaxAgeDuration.
|
|
for height >= 1 && (numBlocks <= params.MaxAgeNumBlocks || !blockTime.Before(minAgeTime)) {
|
|
valSet, err := sm.LoadValidators(stateDB, height)
|
|
if err != nil {
|
|
// last stored height -> return
|
|
if _, ok := err.(sm.ErrNoValSetForHeight); ok {
|
|
return valToLastHeight, nil
|
|
}
|
|
return nil, fmt.Errorf("validator set for height %d not found", height)
|
|
}
|
|
|
|
for _, val := range valSet.Validators {
|
|
key := string(val.Address)
|
|
if _, ok := valToLastHeight[key]; !ok {
|
|
valToLastHeight[key] = height
|
|
}
|
|
}
|
|
|
|
height--
|
|
|
|
if height > 0 {
|
|
// NOTE: we assume here blockStore and state.Validators are in sync. I.e if
|
|
// block N is stored, then validators for height N are also stored in
|
|
// state.
|
|
meta := blockStore.LoadBlockMeta(height)
|
|
if meta == nil {
|
|
return nil, fmt.Errorf("block meta for height %d not found", height)
|
|
}
|
|
blockTime = meta.Header.Time
|
|
}
|
|
|
|
numBlocks++
|
|
}
|
|
|
|
return valToLastHeight, nil
|
|
}
|
|
|
|
// big endian padded hex
|
|
func bE(h int64) string {
|
|
return fmt.Sprintf("%0.16X", h)
|
|
}
|
|
|
|
func keyCommitted(evidence types.Evidence) []byte {
|
|
return append([]byte{baseKeyCommitted}, keySuffix(evidence)...)
|
|
}
|
|
|
|
func keyPending(evidence types.Evidence) []byte {
|
|
return append([]byte{baseKeyPending}, keySuffix(evidence)...)
|
|
}
|
|
|
|
func keyPOLC(polc types.ProofOfLockChange) []byte {
|
|
return keyPOLCFromHeightAndRound(polc.Height(), polc.Round())
|
|
}
|
|
|
|
func keyPOLCFromHeightAndRound(height int64, round int) []byte {
|
|
return append([]byte{baseKeyPOLC}, []byte(fmt.Sprintf("%s/%s", bE(height), bE(int64(round))))...)
|
|
}
|
|
|
|
func keySuffix(evidence types.Evidence) []byte {
|
|
return []byte(fmt.Sprintf("%s/%X", bE(evidence.Height()), evidence.Hash()))
|
|
}
|
|
|
|
// ErrInvalidEvidence returns when evidence failed to validate
|
|
type ErrInvalidEvidence struct {
|
|
Reason error
|
|
}
|
|
|
|
func (e ErrInvalidEvidence) Error() string {
|
|
return fmt.Sprintf("evidence is not valid: %v ", e.Reason)
|
|
}
|