Esempio n. 1
0
// 4 vals.
// polka P1 at R1, P2 at R2, and P3 at R3,
// we lock on P1 at R1, don't see P2, and unlock using P3 at R3
// then we should make sure we don't lock using P2
func TestLockPOLSafety2(t *testing.T) {
	css, privVals := simpleConsensusState(4)
	cs1, cs2, cs3, cs4 := css[0], css[1], css[2], css[3]
	cs1.newStepCh = make(chan *RoundState) // so it blocks

	timeoutChan := make(chan *types.EventDataRoundState)
	voteChan := make(chan *types.EventDataVote)
	evsw := events.NewEventSwitch()
	evsw.OnStart()
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutPropose(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutWait(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringVote(), func(data types.EventData) {
		vote := data.(*types.EventDataVote)
		// we only fire for our own votes
		if bytes.Equal(cs1.privValidator.Address, vote.Address) {
			voteChan <- vote
		}
	})
	cs1.SetFireable(evsw)

	// start round and wait for propose and prevote
	cs1.EnterNewRound(cs1.Height, 0, false)
	_, _, _ = <-cs1.NewStepCh(), <-voteChan, <-cs1.NewStepCh()

	theBlockHash := cs1.ProposalBlock.Hash()

	donePrecommit := make(chan struct{})
	go func() {
		<-voteChan
		<-cs1.NewStepCh()
		donePrecommit <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header(), cs2, cs3, cs4)
	<-donePrecommit

	// the proposed block should now be locked and our precommit added
	validatePrecommit(t, cs1, 0, 0, privVals[0], theBlockHash, theBlockHash)

	donePrecommitWait := make(chan struct{})
	go func() {
		<-cs1.NewStepCh()
		donePrecommitWait <- struct{}{}
	}()
	// add precommits from the rest
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs4)
	signAddVoteToFrom(types.VoteTypePrecommit, cs1, cs3, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header())
	<-donePrecommitWait

	// before we time out into new round, set next proposer
	// and next proposal block
	_, v1 := cs1.Validators.GetByAddress(privVals[0].Address)
	v1.VotingPower = 1
	if updated := cs1.Validators.Update(v1); !updated {
		t.Fatal("failed to update validator")
	}

	cs2.decideProposal(cs2.Height, cs2.Round+1)
	prop, propBlock := cs2.Proposal, cs2.ProposalBlock
	if prop == nil || propBlock == nil {
		t.Fatal("Failed to create proposal block with cs2")
	}

	incrementRound(cs2, cs3, cs4)

	// timeout to new round
	<-timeoutChan

	log.Info("### ONTO Round 2")
	/*Round2
	// we timeout and prevote our lock
	// a polka happened but we didn't see it!
	*/

	// now we're on a new round and not the proposer, so wait for timeout
	_, _ = <-cs1.NewStepCh(), <-timeoutChan
	// go to prevote, prevote for locked block
	_, _ = <-voteChan, <-cs1.NewStepCh()
	validatePrevote(t, cs1, 0, privVals[0], cs1.LockedBlock.Hash())

	// the others sign a polka but we don't see it
	prevotes := signVoteMany(types.VoteTypePrevote, propBlock.Hash(), propBlock.MakePartSet().Header(), cs2, cs3, cs4)

	// once we see prevotes for the next round we'll skip ahead

	incrementRound(cs2, cs3, cs4)

	log.Info("### ONTO Round 3")
	/*Round3
	a polka for nil causes us to unlock
	*/

	// these prevotes will send us straight to precommit at the higher round
	donePrecommit = make(chan struct{})
	go func() {
		select {
		case <-cs1.NewStepCh(): // we're in PrevoteWait, go to Precommit
			<-voteChan
		case <-voteChan: // we went straight to Precommit
		}
		<-cs1.NewStepCh()
		donePrecommit <- struct{}{}
	}()
	// now lets add prevotes from everyone else for nil
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, nil, types.PartSetHeader{}, cs2, cs3, cs4)
	<-donePrecommit

	// we should have unlocked
	// NOTE: we don't lock on nil, so LockedRound is still 0
	validatePrecommit(t, cs1, 2, 0, privVals[0], nil, nil)

	donePrecommitWait = make(chan struct{})
	go func() {
		// the votes will bring us to new round right away
		// we should timeut of it and go to prevote
		<-cs1.NewStepCh()
		// set the proposal block to be that which got a polka in R2
		cs1.mtx.Lock()
		cs1.Proposal, cs1.ProposalBlock, cs1.ProposalBlockParts = prop, propBlock, propBlock.MakePartSet()
		cs1.mtx.Unlock()
		// timeout into prevote, finish prevote
		_, _, _ = <-timeoutChan, <-voteChan, <-cs1.NewStepCh()
		donePrecommitWait <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs3)
	<-donePrecommitWait

	log.Info("### ONTO ROUND 4")
	/*Round4
	we see the polka from R2
	make sure we don't lock because of it!
	*/
	// new round and not proposer
	// (we already timed out and stepped into prevote)

	log.Warn("adding prevotes from round 2")

	addVoteToFromMany(cs1, prevotes, cs2, cs3, cs4)

	log.Warn("Done adding prevotes!")

	// we should prevote it now
	validatePrevote(t, cs1, 3, privVals[0], cs1.ProposalBlock.Hash())

	// but we shouldn't precommit it
	precommits := cs1.Votes.Precommits(3)
	vote := precommits.GetByIndex(0)
	if vote != nil {
		t.Fatal("validator precommitted at round 4 based on an old polka")
	}
}
Esempio n. 2
0
// 4 vals
// a polka at round 1 but we miss it
// then a polka at round 2 that we lock on
// then we see the polka from round 1 but shouldn't unlock
func TestLockPOLSafety1(t *testing.T) {
	css, privVals := simpleConsensusState(4)
	cs1, cs2, cs3, cs4 := css[0], css[1], css[2], css[3]
	cs1.newStepCh = make(chan *RoundState) // so it blocks

	timeoutChan := make(chan *types.EventDataRoundState)
	voteChan := make(chan *types.EventDataVote)
	evsw := events.NewEventSwitch()
	evsw.OnStart()
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutPropose(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutWait(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringVote(), func(data types.EventData) {
		vote := data.(*types.EventDataVote)
		// we only fire for our own votes
		if bytes.Equal(cs1.privValidator.Address, vote.Address) {
			voteChan <- vote
		}
	})
	cs1.SetFireable(evsw)

	// start round and wait for propose and prevote
	cs1.EnterNewRound(cs1.Height, 0, false)
	_, _, _ = <-cs1.NewStepCh(), <-voteChan, <-cs1.NewStepCh()

	propBlock := cs1.ProposalBlock

	validatePrevote(t, cs1, 0, privVals[0], cs1.ProposalBlock.Hash())

	// the others sign a polka but we don't see it
	prevotes := signVoteMany(types.VoteTypePrevote, propBlock.Hash(), propBlock.MakePartSet().Header(), cs2, cs3, cs4)

	// before we time out into new round, set next proposer
	// and next proposal block
	_, v1 := cs1.Validators.GetByAddress(privVals[0].Address)
	v1.VotingPower = 1
	if updated := cs1.Validators.Update(v1); !updated {
		t.Fatal("failed to update validator")
	}

	log.Warn("old prop", "hash", fmt.Sprintf("%X", propBlock.Hash()))

	// we do see them precommit nil
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs3, cs4)

	cs2.decideProposal(cs2.Height, cs2.Round+1)
	prop, propBlock := cs2.Proposal, cs2.ProposalBlock
	if prop == nil || propBlock == nil {
		t.Fatal("Failed to create proposal block with cs2")
	}

	incrementRound(cs2, cs3, cs4)

	log.Info("### ONTO ROUND 2")
	/*Round2
	// we timeout and prevote our lock
	// a polka happened but we didn't see it!
	*/

	// now we're on a new round and not the proposer,
	<-cs1.NewStepCh()
	// so set proposal
	cs1.mtx.Lock()
	propBlockHash, propBlockParts := propBlock.Hash(), propBlock.MakePartSet()
	cs1.Proposal, cs1.ProposalBlock, cs1.ProposalBlockParts = prop, propBlock, propBlockParts
	cs1.mtx.Unlock()
	// and wait for timeout
	<-timeoutChan
	if cs1.LockedBlock != nil {
		t.Fatal("we should not be locked!")
	}
	log.Warn("new prop", "hash", fmt.Sprintf("%X", propBlockHash))
	// go to prevote, prevote for proposal block
	_, _ = <-voteChan, <-cs1.NewStepCh()
	validatePrevote(t, cs1, 1, privVals[0], propBlockHash)

	// now we see the others prevote for it, so we should lock on it
	donePrecommit := make(chan struct{})
	go func() {
		select {
		case <-cs1.NewStepCh(): // we're in PrevoteWait, go to Precommit
			<-voteChan
		case <-voteChan: // we went straight to Precommit
		}
		<-cs1.NewStepCh()
		donePrecommit <- struct{}{}
	}()
	// now lets add prevotes from everyone else for nil
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, propBlockHash, propBlockParts.Header(), cs2, cs3, cs4)
	<-donePrecommit

	// we should have precommitted
	validatePrecommit(t, cs1, 1, 1, privVals[0], propBlockHash, propBlockHash)

	// now we see precommits for nil
	donePrecommitWait := make(chan struct{})
	go func() {
		// the votes will bring us to new round
		// we should timeut of it and go to prevote
		<-cs1.NewStepCh()
		<-timeoutChan
		donePrecommitWait <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs3)
	<-donePrecommitWait

	incrementRound(cs2, cs3, cs4)

	log.Info("### ONTO ROUND 3")
	/*Round3
	we see the polka from round 1 but we shouldn't unlock!
	*/

	// timeout of propose
	_, _ = <-cs1.NewStepCh(), <-timeoutChan

	// finish prevote
	_, _ = <-voteChan, <-cs1.NewStepCh()

	// we should prevote what we're locked on
	validatePrevote(t, cs1, 2, privVals[0], propBlockHash)

	// add prevotes from the earlier round
	addVoteToFromMany(cs1, prevotes, cs2, cs3, cs4)

	log.Warn("Done adding prevotes!")

	ensureNoNewStep(t, cs1)
}
Esempio n. 3
0
// 4 vals, one precommits, other 3 polka at next round, so we unlock and precomit the polka
func TestLockPOLRelock(t *testing.T) {
	css, privVals := simpleConsensusState(4)
	cs1, cs2, cs3, cs4 := css[0], css[1], css[2], css[3]
	cs1.newStepCh = make(chan *RoundState) // so it blocks

	timeoutChan := make(chan *types.EventDataRoundState)
	voteChan := make(chan *types.EventDataVote)
	evsw := events.NewEventSwitch()
	evsw.OnStart()
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutPropose(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutWait(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringVote(), func(data types.EventData) {
		vote := data.(*types.EventDataVote)
		// we only fire for our own votes
		if bytes.Equal(cs1.privValidator.Address, vote.Address) {
			voteChan <- vote
		}
	})
	cs1.SetFireable(evsw)

	// everything done from perspective of cs1

	/*
		Round1 (cs1, B) // B B B B// B nil B nil

		eg. cs2 and cs4 didn't see the 2/3 prevotes
	*/

	// start round and wait for propose and prevote
	cs1.EnterNewRound(cs1.Height, 0, false)
	_, _, _ = <-cs1.NewStepCh(), <-voteChan, <-cs1.NewStepCh()

	theBlockHash := cs1.ProposalBlock.Hash()

	// wait to finish precommit after prevotes done
	// we do this in a go routine with another channel since otherwise
	// we may get deadlock with EnterPrecommit waiting to send on newStepCh and the final
	// signAddVoteToFrom waiting for the cs.mtx.Lock
	donePrecommit := make(chan struct{})
	go func() {
		<-voteChan
		<-cs1.NewStepCh()
		donePrecommit <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header(), cs2, cs3, cs4)
	<-donePrecommit

	// the proposed block should now be locked and our precommit added
	validatePrecommit(t, cs1, 0, 0, privVals[0], theBlockHash, theBlockHash)

	donePrecommitWait := make(chan struct{})
	go func() {
		// (note we're entering precommit for a second time this round)
		// but with invalid args. then we EnterPrecommitWait, twice (?)
		<-cs1.NewStepCh()
		donePrecommitWait <- struct{}{}
	}()
	// add precommits from the rest
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs4)
	signAddVoteToFrom(types.VoteTypePrecommit, cs1, cs3, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header())
	<-donePrecommitWait

	// before we time out into new round, set next proposer
	// and next proposal block
	_, v1 := cs1.Validators.GetByAddress(privVals[0].Address)
	v1.VotingPower = 1
	if updated := cs1.Validators.Update(v1); !updated {
		t.Fatal("failed to update validator")
	}

	cs2.decideProposal(cs2.Height, cs2.Round+1)
	prop, propBlock := cs2.Proposal, cs2.ProposalBlock
	if prop == nil || propBlock == nil {
		t.Fatal("Failed to create proposal block with cs2")
	}

	incrementRound(cs2, cs3, cs4)

	// timeout to new round
	te := <-timeoutChan
	if te.Step != RoundStepPrecommitWait.String() {
		t.Fatalf("expected to timeout of precommit into new round. got %v", te.Step)
	}

	log.Info("### ONTO ROUND 2")

	/*
		Round2 (cs2, C) // B C C C // C C C _)

		cs1 changes lock!
	*/

	// now we're on a new round and not the proposer
	<-cs1.NewStepCh()
	cs1.mtx.Lock()
	// so set the proposal block
	propBlockHash, propBlockParts := propBlock.Hash(), propBlock.MakePartSet()
	cs1.Proposal, cs1.ProposalBlock, cs1.ProposalBlockParts = prop, propBlock, propBlockParts
	cs1.mtx.Unlock()
	// and wait for timeout
	te = <-timeoutChan
	if te.Step != RoundStepPropose.String() {
		t.Fatalf("expected to timeout of propose. got %v", te.Step)
	}
	// go to prevote, prevote for locked block (not proposal), move on
	_, _ = <-voteChan, <-cs1.NewStepCh()
	validatePrevote(t, cs1, 0, privVals[0], theBlockHash)

	donePrecommit = make(chan struct{})
	go func() {
		//  we need this go routine because if we go into PrevoteWait it has to pull on newStepCh
		// before the final vote will get added (because it holds the mutex).
		select {
		case <-cs1.NewStepCh(): // we're in PrevoteWait, go to Precommit
			<-voteChan
		case <-voteChan: // we went straight to Precommit
		}
		donePrecommit <- struct{}{}
	}()
	// now lets add prevotes from everyone else for the new block
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, propBlockHash, propBlockParts.Header(), cs2, cs3, cs4)
	<-donePrecommit

	// we should have unlocked and locked on the new block
	validatePrecommit(t, cs1, 1, 1, privVals[0], propBlockHash, propBlockHash)

	donePrecommitWait = make(chan struct{})
	go func() {
		// (note we're entering precommit for a second time this round)
		// but with invalid args. then we EnterPrecommitWait,
		<-cs1.NewStepCh()
		donePrecommitWait <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, propBlockHash, propBlockParts.Header(), cs2, cs3)
	<-donePrecommitWait

	<-cs1.NewStepCh()
	rs := <-cs1.NewStepCh()
	if rs.Height != 2 {
		t.Fatal("Expected height to increment")
	}

	if hash, _, ok := rs.LastCommit.TwoThirdsMajority(); !ok || !bytes.Equal(hash, propBlockHash) {
		t.Fatal("Expected block to get committed")
	}
}
Esempio n. 4
0
// 4 vals, one precommits, other 3 polka at next round, so we unlock and precomit the polka
func TestLockPOLUnlock(t *testing.T) {
	css, privVals := simpleConsensusState(4)
	cs1, cs2, cs3, cs4 := css[0], css[1], css[2], css[3]
	cs1.newStepCh = make(chan *RoundState) // so it blocks

	timeoutChan := make(chan *types.EventDataRoundState)
	voteChan := make(chan *types.EventDataVote)
	evsw := events.NewEventSwitch()
	evsw.OnStart()
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutPropose(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringTimeoutWait(), func(data types.EventData) {
		timeoutChan <- data.(*types.EventDataRoundState)
	})
	evsw.AddListenerForEvent("tester", types.EventStringVote(), func(data types.EventData) {
		vote := data.(*types.EventDataVote)
		// we only fire for our own votes
		if bytes.Equal(cs1.privValidator.Address, vote.Address) {
			voteChan <- vote
		}
	})
	cs1.SetFireable(evsw)

	// everything done from perspective of cs1

	/*
		Round1 (cs1, B) // B B B B // B nil B nil

		eg. didn't see the 2/3 prevotes
	*/

	// start round and wait for propose and prevote
	cs1.EnterNewRound(cs1.Height, 0, false)
	_, _, _ = <-cs1.NewStepCh(), <-voteChan, <-cs1.NewStepCh()

	theBlockHash := cs1.ProposalBlock.Hash()

	donePrecommit := make(chan struct{})
	go func() {
		<-voteChan
		<-cs1.NewStepCh()
		donePrecommit <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header(), cs2, cs3, cs4)
	<-donePrecommit

	// the proposed block should now be locked and our precommit added
	validatePrecommit(t, cs1, 0, 0, privVals[0], theBlockHash, theBlockHash)

	donePrecommitWait := make(chan struct{})
	go func() {
		<-cs1.NewStepCh()
		donePrecommitWait <- struct{}{}
	}()
	// add precommits from the rest
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs4)
	signAddVoteToFrom(types.VoteTypePrecommit, cs1, cs3, cs1.ProposalBlock.Hash(), cs1.ProposalBlockParts.Header())
	<-donePrecommitWait

	// before we time out into new round, set next proposer
	// and next proposal block
	_, v1 := cs1.Validators.GetByAddress(privVals[0].Address)
	v1.VotingPower = 1
	if updated := cs1.Validators.Update(v1); !updated {
		t.Fatal("failed to update validator")
	}

	cs2.decideProposal(cs2.Height, cs2.Round+1)
	prop, propBlock := cs2.Proposal, cs2.ProposalBlock
	if prop == nil || propBlock == nil {
		t.Fatal("Failed to create proposal block with cs2")
	}

	incrementRound(cs2, cs3, cs4)

	// timeout to new round
	<-timeoutChan

	log.Info("#### ONTO ROUND 2")
	/*
		Round2 (cs2, C) // B nil nil nil // nil nil nil _

		cs1 unlocks!
	*/

	// now we're on a new round and not the proposer,
	<-cs1.NewStepCh()
	cs1.mtx.Lock()
	// so set the proposal block
	cs1.Proposal, cs1.ProposalBlock, cs1.ProposalBlockParts = prop, propBlock, propBlock.MakePartSet()
	lockedBlockHash := cs1.LockedBlock.Hash()
	cs1.mtx.Unlock()
	// and wait for timeout
	<-timeoutChan

	// go to prevote, prevote for locked block (not proposal)
	_, _ = <-voteChan, <-cs1.NewStepCh()
	validatePrevote(t, cs1, 0, privVals[0], lockedBlockHash)

	donePrecommit = make(chan struct{})
	go func() {
		select {
		case <-cs1.NewStepCh(): // we're in PrevoteWait, go to Precommit
			<-voteChan
		case <-voteChan: // we went straight to Precommit
		}
		donePrecommit <- struct{}{}
	}()
	// now lets add prevotes from everyone else for the new block
	signAddVoteToFromMany(types.VoteTypePrevote, cs1, nil, types.PartSetHeader{}, cs2, cs3, cs4)
	<-donePrecommit

	// we should have unlocked
	// NOTE: we don't lock on nil, so LockedRound is still 0
	validatePrecommit(t, cs1, 1, 0, privVals[0], nil, nil)

	donePrecommitWait = make(chan struct{})
	go func() {
		// the votes will bring us to new round right away
		// we should timeout of it
		_, _, _ = <-cs1.NewStepCh(), <-cs1.NewStepCh(), <-timeoutChan
		donePrecommitWait <- struct{}{}
	}()
	signAddVoteToFromMany(types.VoteTypePrecommit, cs1, nil, types.PartSetHeader{}, cs2, cs3)
	<-donePrecommitWait
}
Esempio n. 5
0
func (cs *ConsensusState) addVote(valIndex int, vote *types.Vote, peerKey string) (added bool, address []byte, err error) {
	log.Debug("addVote", "voteHeight", vote.Height, "voteType", vote.Type, "csHeight", cs.Height)

	defer func() {
		if added {
			cs.evsw.FireEvent(types.EventStringVote(), &types.EventDataVote{valIndex, address, vote})
		}
	}()

	// A precommit for the previous height?
	if vote.Height+1 == cs.Height {
		if !(cs.Step == RoundStepNewHeight && vote.Type == types.VoteTypePrecommit) {
			// TODO: give the reason ..
			// fmt.Errorf("TryAddVote: Wrong height, not a LastCommit straggler commit.")
			return added, nil, ErrVoteHeightMismatch
		}
		added, address, err = cs.LastCommit.AddByIndex(valIndex, vote)
		if added {
			log.Info(Fmt("Added to lastPrecommits: %v", cs.LastCommit.StringShort()))
		}
		return
	}

	// A prevote/precommit for this height?
	if vote.Height == cs.Height {
		height := cs.Height
		added, address, err = cs.Votes.AddByIndex(valIndex, vote, peerKey)
		if added {
			switch vote.Type {
			case types.VoteTypePrevote:
				prevotes := cs.Votes.Prevotes(vote.Round)
				log.Info(Fmt("Added to prevotes: %v", prevotes.StringShort()))
				// First, unlock if prevotes is a valid POL.
				// >> lockRound < POLRound <= unlockOrChangeLockRound (see spec)
				// NOTE: If (lockRound < POLRound) but !(POLRound <= unlockOrChangeLockRound),
				// we'll still EnterNewRound(H,vote.R) and EnterPrecommit(H,vote.R) to process it
				// there.
				if (cs.LockedBlock != nil) && (cs.LockedRound < vote.Round) && (vote.Round <= cs.Round) {
					hash, _, ok := prevotes.TwoThirdsMajority()
					if ok && !cs.LockedBlock.HashesTo(hash) {
						log.Notice("Unlocking because of POL.", "lockedRound", cs.LockedRound, "POLRound", vote.Round)
						cs.LockedRound = 0
						cs.LockedBlock = nil
						cs.LockedBlockParts = nil
						cs.evsw.FireEvent(types.EventStringUnlock(), cs.RoundStateEvent())
					}
				}
				if cs.Round <= vote.Round && prevotes.HasTwoThirdsAny() {
					// Round-skip over to PrevoteWait or goto Precommit.
					go func() {
						cs.EnterNewRound(height, vote.Round, false)
						if prevotes.HasTwoThirdsMajority() {
							cs.EnterPrecommit(height, vote.Round, false)
						} else {
							cs.EnterPrevote(height, vote.Round, false)
							cs.EnterPrevoteWait(height, vote.Round)
						}
					}()
				} else if cs.Proposal != nil && 0 <= cs.Proposal.POLRound && cs.Proposal.POLRound == vote.Round {
					// If the proposal is now complete, enter prevote of cs.Round.
					if cs.isProposalComplete() {
						go cs.EnterPrevote(height, cs.Round, false)
					}
				}
			case types.VoteTypePrecommit:
				precommits := cs.Votes.Precommits(vote.Round)
				log.Info(Fmt("Added to precommit: %v", precommits.StringShort()))
				hash, _, ok := precommits.TwoThirdsMajority()
				if ok {
					go func() {
						if len(hash) == 0 {
							cs.EnterNewRound(height, vote.Round+1, false)
						} else {
							cs.EnterNewRound(height, vote.Round, false)
							cs.EnterPrecommit(height, vote.Round, false)
							cs.EnterCommit(height, vote.Round)
						}
					}()
				} else if cs.Round <= vote.Round && precommits.HasTwoThirdsAny() {
					go func() {
						cs.EnterNewRound(height, vote.Round, false)
						cs.EnterPrecommit(height, vote.Round, false)
						cs.EnterPrecommitWait(height, vote.Round)
					}()
				}
			default:
				PanicSanity(Fmt("Unexpected vote type %X", vote.Type)) // Should not happen.
			}
		}
		// Either duplicate, or error upon cs.Votes.AddByIndex()
		return
	} else {
		err = ErrVoteHeightMismatch
	}

	// Height mismatch, bad peer?
	log.Info("Vote ignored and not added", "voteHeight", vote.Height, "csHeight", cs.Height)
	return
}