tendermint/consensus/vote_set.go

303 lines
8.6 KiB
Go

package consensus
import (
"bytes"
"fmt"
"strings"
"sync"
"github.com/tendermint/tendermint/account"
"github.com/tendermint/tendermint/binary"
. "github.com/tendermint/tendermint/common"
sm "github.com/tendermint/tendermint/state"
"github.com/tendermint/tendermint/types"
)
// VoteSet helps collect signatures from validators at each height+round
// for a predefined vote type.
// Note that there three kinds of votes: prevotes, precommits, and commits.
// A commit of prior rounds can be added added in lieu of votes/precommits.
// NOTE: Assumes that the sum total of voting power does not exceed MaxUInt64.
type VoteSet struct {
height uint
round uint
type_ byte
mtx sync.Mutex
valSet *sm.ValidatorSet
votes []*types.Vote // validator index -> vote
votesBitArray *BitArray // validator index -> has vote?
votesByBlock map[string]uint64 // string(blockHash)+string(blockParts) -> vote sum.
totalVotes uint64
maj23Hash []byte
maj23Parts types.PartSetHeader
maj23Exists bool
}
// Constructs a new VoteSet struct used to accumulate votes for given height/round.
func NewVoteSet(height uint, round uint, type_ byte, valSet *sm.ValidatorSet) *VoteSet {
if height == 0 {
panic("Cannot make VoteSet for height == 0, doesn't make sense.")
}
return &VoteSet{
height: height,
round: round,
type_: type_,
valSet: valSet,
votes: make([]*types.Vote, valSet.Size()),
votesBitArray: NewBitArray(valSet.Size()),
votesByBlock: make(map[string]uint64),
totalVotes: 0,
}
}
func (voteSet *VoteSet) Height() uint {
if voteSet == nil {
return 0
} else {
return voteSet.height
}
}
func (voteSet *VoteSet) Round() uint {
if voteSet == nil {
return 0
} else {
return voteSet.round
}
}
func (voteSet *VoteSet) Size() uint {
if voteSet == nil {
return 0
} else {
return voteSet.valSet.Size()
}
}
// Returns added=true, index if vote was added
// Otherwise returns err=ErrVote[UnexpectedStep|InvalidAccount|InvalidSignature|InvalidBlockHash|ConflictingSignature]
// Duplicate votes return added=false, err=nil.
// NOTE: vote should not be mutated after adding.
func (voteSet *VoteSet) AddByIndex(valIndex uint, vote *types.Vote) (added bool, index uint, err error) {
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return voteSet.addByIndex(valIndex, vote)
}
// Returns added=true, index if vote was added
// Otherwise returns err=ErrVote[UnexpectedStep|InvalidAccount|InvalidSignature|InvalidBlockHash|ConflictingSignature]
// Duplicate votes return added=false, err=nil.
// NOTE: vote should not be mutated after adding.
func (voteSet *VoteSet) AddByAddress(address []byte, vote *types.Vote) (added bool, index uint, err error) {
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
// Ensure that signer is a validator.
valIndex, val := voteSet.valSet.GetByAddress(address)
if val == nil {
return false, 0, types.ErrVoteInvalidAccount
}
return voteSet.addVote(val, valIndex, vote)
}
func (voteSet *VoteSet) addByIndex(valIndex uint, vote *types.Vote) (bool, uint, error) {
// Ensure that signer is a validator.
_, val := voteSet.valSet.GetByIndex(valIndex)
if val == nil {
return false, 0, types.ErrVoteInvalidAccount
}
return voteSet.addVote(val, valIndex, vote)
}
func (voteSet *VoteSet) addVote(val *sm.Validator, valIndex uint, vote *types.Vote) (bool, uint, error) {
// Make sure the step matches. (or that vote is commit && round < voteSet.round)
if (vote.Height != voteSet.height) ||
(vote.Round != voteSet.round) ||
(vote.Type != voteSet.type_) {
return false, 0, types.ErrVoteUnexpectedStep
}
// Check signature.
if !val.PubKey.VerifyBytes(account.SignBytes(config.GetString("chain_id"), vote), vote.Signature) {
// Bad signature.
return false, 0, types.ErrVoteInvalidSignature
}
// If vote already exists, return false.
if existingVote := voteSet.votes[valIndex]; existingVote != nil {
if bytes.Equal(existingVote.BlockHash, vote.BlockHash) {
return false, valIndex, nil
} else {
return false, valIndex, &types.ErrVoteConflictingSignature{
VoteA: existingVote,
VoteB: vote,
}
}
}
// Add vote.
voteSet.votes[valIndex] = vote
voteSet.votesBitArray.SetIndex(valIndex, true)
blockKey := string(vote.BlockHash) + string(binary.BinaryBytes(vote.BlockParts))
totalBlockHashVotes := voteSet.votesByBlock[blockKey] + val.VotingPower
voteSet.votesByBlock[blockKey] = totalBlockHashVotes
voteSet.totalVotes += val.VotingPower
// If we just nudged it up to two thirds majority, add it.
if totalBlockHashVotes > voteSet.valSet.TotalVotingPower()*2/3 &&
(totalBlockHashVotes-val.VotingPower) <= voteSet.valSet.TotalVotingPower()*2/3 {
voteSet.maj23Hash = vote.BlockHash
voteSet.maj23Parts = vote.BlockParts
voteSet.maj23Exists = true
}
return true, valIndex, nil
}
func (voteSet *VoteSet) BitArray() *BitArray {
if voteSet == nil {
return nil
}
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return voteSet.votesBitArray.Copy()
}
func (voteSet *VoteSet) GetByIndex(valIndex uint) *types.Vote {
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return voteSet.votes[valIndex]
}
func (voteSet *VoteSet) GetByAddress(address []byte) *types.Vote {
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
valIndex, val := voteSet.valSet.GetByAddress(address)
if val == nil {
panic("GetByAddress(address) returned nil")
}
return voteSet.votes[valIndex]
}
func (voteSet *VoteSet) HasTwoThirdsMajority() bool {
if voteSet == nil {
return false
}
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return voteSet.maj23Exists
}
func (voteSet *VoteSet) HasTwoThirdsAny() bool {
if voteSet == nil {
return false
}
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return voteSet.totalBlockHashVotes > voteSet.valSet.TotalVotingPower()*2/3
}
// Returns either a blockhash (or nil) that received +2/3 majority.
// If there exists no such majority, returns (nil, false).
func (voteSet *VoteSet) TwoThirdsMajority() (hash []byte, parts types.PartSetHeader, ok bool) {
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
if voteSet.maj23Exists {
return voteSet.maj23Hash, voteSet.maj23Parts, true
} else {
return nil, types.PartSetHeader{}, false
}
}
func (voteSet *VoteSet) String() string {
return voteSet.StringIndented("")
}
func (voteSet *VoteSet) StringIndented(indent string) string {
voteStrings := make([]string, len(voteSet.votes))
for i, vote := range voteSet.votes {
if vote == nil {
voteStrings[i] = "nil-Vote"
} else {
voteStrings[i] = vote.String()
}
}
return fmt.Sprintf(`VoteSet{
%s H:%v R:%v T:%v
%s %v
%s %v
%s}`,
indent, voteSet.height, voteSet.round, voteSet.type_,
indent, strings.Join(voteStrings, "\n"+indent+" "),
indent, voteSet.votesBitArray,
indent)
}
func (voteSet *VoteSet) StringShort() string {
if voteSet == nil {
return "nil-VoteSet"
}
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
return fmt.Sprintf(`VoteSet{H:%v R:%v T:%v +2/3:%v %v}`,
voteSet.height, voteSet.round, voteSet.type_, voteSet.maj23Exists, voteSet.votesBitArray)
}
//--------------------------------------------------------------------------------
// Validation
func (voteSet *VoteSet) MakeValidation() *types.Validation {
if voteSet.type_ != types.VoteTypePrecommit {
panic("Cannot MakeValidation() unless VoteSet.Type is types.VoteTypePrecommit")
}
voteSet.mtx.Lock()
defer voteSet.mtx.Unlock()
if len(voteSet.maj23Hash) == 0 {
panic("Cannot MakeValidation() unless a blockhash has +2/3")
}
precommits := make([]types.Precommit, voteSet.valSet.Size())
voteSet.valSet.Iterate(func(valIndex uint, val *sm.Validator) bool {
vote := voteSet.votes[valIndex]
if vote == nil {
return false
}
if !bytes.Equal(vote.BlockHash, voteSet.maj23Hash) {
return false
}
if !vote.BlockParts.Equals(voteSet.maj23Parts) {
return false
}
precommits[valIndex] = types.Precommit{val.Address, vote.Signature}
return false
})
return &types.Validation{
Round: voteSet.round,
Precommits: precommits,
}
}
// XXX
func VoteSetFromValidation(validation *types.Validation) *VoteSet {
lastPrecommits := NewVoteSet(state.LastBlockHeight, 0, types.VoteTypePrecommit, state.LastBondedValidators)
seenValidation := cs.blockStore.LoadSeenValidation(state.LastBlockHeight)
for idx, precommit := range seenValidation.Precommits {
precommitVote := &types.Vote{
Height: state.LastBlockHeight,
Round: seenValidation.Round,
Type: types.VoteTypePrecommit,
BlockHash: state.LastBlockHash,
BlockParts: state.LastBlockParts,
Signature: precommit.Signature,
}
added, _, err := lastPrecommits.AddByIndex(uint(idx), precommitVote)
if !added || err != nil {
panic(Fmt("Failed to reconstruct LastPrecommits: %v", err))
}
}
}