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package types
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import (
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"bytes"
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"fmt"
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"math"
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"math/big"
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"sort"
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"strings"
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"github.com/pkg/errors"
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"github.com/tendermint/tendermint/crypto/merkle"
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)
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// MaxTotalVotingPower - the maximum allowed total voting power.
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// It needs to be sufficiently small to, in all cases:
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// 1. prevent clipping in incrementProposerPriority()
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// 2. let (diff+diffMax-1) not overflow in IncrementProposerPriority()
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// (Proof of 1 is tricky, left to the reader).
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// It could be higher, but this is sufficiently large for our purposes,
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// and leaves room for defensive purposes.
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// PriorityWindowSizeFactor - is a constant that when multiplied with the total voting power gives
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// the maximum allowed distance between validator priorities.
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const (
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MaxTotalVotingPower = int64(math.MaxInt64) / 8
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PriorityWindowSizeFactor = 2
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)
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// ValidatorSet represent a set of *Validator at a given height.
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// The validators can be fetched by address or index.
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// The index is in order of .Address, so the indices are fixed
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// for all rounds of a given blockchain height - ie. the validators
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// are sorted by their address.
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// On the other hand, the .ProposerPriority of each validator and
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// the designated .GetProposer() of a set changes every round,
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// upon calling .IncrementProposerPriority().
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// NOTE: Not goroutine-safe.
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// NOTE: All get/set to validators should copy the value for safety.
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type ValidatorSet struct {
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// NOTE: persisted via reflect, must be exported.
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Validators []*Validator `json:"validators"`
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Proposer *Validator `json:"proposer"`
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// cached (unexported)
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totalVotingPower int64
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}
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// NewValidatorSet initializes a ValidatorSet by copying over the
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// values from `valz`, a list of Validators. If valz is nil or empty,
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// the new ValidatorSet will have an empty list of Validators.
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// The addresses of validators in `valz` must be unique otherwise the
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// function panics.
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// Note the validator set size has an implied limit equal to that of the MaxVotesCount -
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// commits by a validator set larger than this will fail validation.
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func NewValidatorSet(valz []*Validator) *ValidatorSet {
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vals := &ValidatorSet{}
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err := vals.updateWithChangeSet(valz, false)
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if err != nil {
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panic(fmt.Sprintf("cannot create validator set: %s", err))
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}
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if len(valz) > 0 {
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vals.IncrementProposerPriority(1)
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}
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return vals
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}
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// Nil or empty validator sets are invalid.
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func (vals *ValidatorSet) IsNilOrEmpty() bool {
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return vals == nil || len(vals.Validators) == 0
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}
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// Increment ProposerPriority and update the proposer on a copy, and return it.
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func (vals *ValidatorSet) CopyIncrementProposerPriority(times int) *ValidatorSet {
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copy := vals.Copy()
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copy.IncrementProposerPriority(times)
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return copy
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}
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// IncrementProposerPriority increments ProposerPriority of each validator and updates the
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// proposer. Panics if validator set is empty.
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// `times` must be positive.
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func (vals *ValidatorSet) IncrementProposerPriority(times int) {
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if vals.IsNilOrEmpty() {
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panic("empty validator set")
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}
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if times <= 0 {
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panic("Cannot call IncrementProposerPriority with non-positive times")
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}
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// Cap the difference between priorities to be proportional to 2*totalPower by
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// re-normalizing priorities, i.e., rescale all priorities by multiplying with:
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// 2*totalVotingPower/(maxPriority - minPriority)
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diffMax := PriorityWindowSizeFactor * vals.TotalVotingPower()
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vals.RescalePriorities(diffMax)
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vals.shiftByAvgProposerPriority()
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var proposer *Validator
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// Call IncrementProposerPriority(1) times times.
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for i := 0; i < times; i++ {
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proposer = vals.incrementProposerPriority()
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}
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vals.Proposer = proposer
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}
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func (vals *ValidatorSet) RescalePriorities(diffMax int64) {
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if vals.IsNilOrEmpty() {
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panic("empty validator set")
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}
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// NOTE: This check is merely a sanity check which could be
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// removed if all tests would init. voting power appropriately;
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// i.e. diffMax should always be > 0
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if diffMax <= 0 {
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return
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}
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// Calculating ceil(diff/diffMax):
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// Re-normalization is performed by dividing by an integer for simplicity.
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// NOTE: This may make debugging priority issues easier as well.
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diff := computeMaxMinPriorityDiff(vals)
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ratio := (diff + diffMax - 1) / diffMax
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if diff > diffMax {
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for _, val := range vals.Validators {
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val.ProposerPriority /= ratio
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}
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}
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}
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func (vals *ValidatorSet) incrementProposerPriority() *Validator {
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for _, val := range vals.Validators {
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// Check for overflow for sum.
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newPrio := safeAddClip(val.ProposerPriority, val.VotingPower)
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val.ProposerPriority = newPrio
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}
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// Decrement the validator with most ProposerPriority.
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mostest := vals.getValWithMostPriority()
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// Mind the underflow.
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mostest.ProposerPriority = safeSubClip(mostest.ProposerPriority, vals.TotalVotingPower())
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return mostest
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}
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// Should not be called on an empty validator set.
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func (vals *ValidatorSet) computeAvgProposerPriority() int64 {
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n := int64(len(vals.Validators))
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sum := big.NewInt(0)
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for _, val := range vals.Validators {
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sum.Add(sum, big.NewInt(val.ProposerPriority))
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}
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avg := sum.Div(sum, big.NewInt(n))
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if avg.IsInt64() {
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return avg.Int64()
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}
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// This should never happen: each val.ProposerPriority is in bounds of int64.
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panic(fmt.Sprintf("Cannot represent avg ProposerPriority as an int64 %v", avg))
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}
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// Compute the difference between the max and min ProposerPriority of that set.
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func computeMaxMinPriorityDiff(vals *ValidatorSet) int64 {
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if vals.IsNilOrEmpty() {
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panic("empty validator set")
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}
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max := int64(math.MinInt64)
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min := int64(math.MaxInt64)
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for _, v := range vals.Validators {
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if v.ProposerPriority < min {
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min = v.ProposerPriority
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}
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if v.ProposerPriority > max {
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max = v.ProposerPriority
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}
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}
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diff := max - min
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if diff < 0 {
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return -1 * diff
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} else {
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return diff
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}
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}
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func (vals *ValidatorSet) getValWithMostPriority() *Validator {
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var res *Validator
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for _, val := range vals.Validators {
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res = res.CompareProposerPriority(val)
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}
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return res
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}
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func (vals *ValidatorSet) shiftByAvgProposerPriority() {
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if vals.IsNilOrEmpty() {
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panic("empty validator set")
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}
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avgProposerPriority := vals.computeAvgProposerPriority()
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for _, val := range vals.Validators {
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val.ProposerPriority = safeSubClip(val.ProposerPriority, avgProposerPriority)
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}
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}
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// Makes a copy of the validator list.
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func validatorListCopy(valsList []*Validator) []*Validator {
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if valsList == nil {
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return nil
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}
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valsCopy := make([]*Validator, len(valsList))
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for i, val := range valsList {
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valsCopy[i] = val.Copy()
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}
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return valsCopy
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}
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// Copy each validator into a new ValidatorSet.
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func (vals *ValidatorSet) Copy() *ValidatorSet {
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return &ValidatorSet{
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Validators: validatorListCopy(vals.Validators),
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Proposer: vals.Proposer,
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totalVotingPower: vals.totalVotingPower,
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}
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}
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// HasAddress returns true if address given is in the validator set, false -
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// otherwise.
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func (vals *ValidatorSet) HasAddress(address []byte) bool {
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idx := sort.Search(len(vals.Validators), func(i int) bool {
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return bytes.Compare(address, vals.Validators[i].Address) <= 0
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})
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return idx < len(vals.Validators) && bytes.Equal(vals.Validators[idx].Address, address)
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}
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// GetByAddress returns an index of the validator with address and validator
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// itself if found. Otherwise, -1 and nil are returned.
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func (vals *ValidatorSet) GetByAddress(address []byte) (index int, val *Validator) {
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idx := sort.Search(len(vals.Validators), func(i int) bool {
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return bytes.Compare(address, vals.Validators[i].Address) <= 0
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})
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if idx < len(vals.Validators) && bytes.Equal(vals.Validators[idx].Address, address) {
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return idx, vals.Validators[idx].Copy()
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}
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return -1, nil
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}
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// GetByIndex returns the validator's address and validator itself by index.
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// It returns nil values if index is less than 0 or greater or equal to
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// len(ValidatorSet.Validators).
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func (vals *ValidatorSet) GetByIndex(index int) (address []byte, val *Validator) {
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if index < 0 || index >= len(vals.Validators) {
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return nil, nil
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}
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val = vals.Validators[index]
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return val.Address, val.Copy()
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}
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// Size returns the length of the validator set.
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func (vals *ValidatorSet) Size() int {
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return len(vals.Validators)
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}
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// Force recalculation of the set's total voting power.
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func (vals *ValidatorSet) updateTotalVotingPower() {
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sum := int64(0)
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for _, val := range vals.Validators {
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// mind overflow
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sum = safeAddClip(sum, val.VotingPower)
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if sum > MaxTotalVotingPower {
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panic(fmt.Sprintf(
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"Total voting power should be guarded to not exceed %v; got: %v",
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MaxTotalVotingPower,
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sum))
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}
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}
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vals.totalVotingPower = sum
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}
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// TotalVotingPower returns the sum of the voting powers of all validators.
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// It recomputes the total voting power if required.
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func (vals *ValidatorSet) TotalVotingPower() int64 {
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if vals.totalVotingPower == 0 {
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vals.updateTotalVotingPower()
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}
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return vals.totalVotingPower
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}
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// GetProposer returns the current proposer. If the validator set is empty, nil
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// is returned.
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func (vals *ValidatorSet) GetProposer() (proposer *Validator) {
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if len(vals.Validators) == 0 {
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return nil
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}
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if vals.Proposer == nil {
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vals.Proposer = vals.findProposer()
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}
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return vals.Proposer.Copy()
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}
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func (vals *ValidatorSet) findProposer() *Validator {
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var proposer *Validator
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for _, val := range vals.Validators {
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if proposer == nil || !bytes.Equal(val.Address, proposer.Address) {
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proposer = proposer.CompareProposerPriority(val)
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}
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}
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return proposer
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}
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// Hash returns the Merkle root hash build using validators (as leaves) in the
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// set.
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func (vals *ValidatorSet) Hash() []byte {
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if len(vals.Validators) == 0 {
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return nil
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}
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bzs := make([][]byte, len(vals.Validators))
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for i, val := range vals.Validators {
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bzs[i] = val.Bytes()
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}
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return merkle.SimpleHashFromByteSlices(bzs)
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}
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// Iterate will run the given function over the set.
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func (vals *ValidatorSet) Iterate(fn func(index int, val *Validator) bool) {
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for i, val := range vals.Validators {
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stop := fn(i, val.Copy())
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if stop {
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break
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}
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}
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}
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// Checks changes against duplicates, splits the changes in updates and removals, sorts them by address.
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//
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// Returns:
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// updates, removals - the sorted lists of updates and removals
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// err - non-nil if duplicate entries or entries with negative voting power are seen
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//
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// No changes are made to 'origChanges'.
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func processChanges(origChanges []*Validator) (updates, removals []*Validator, err error) {
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// Make a deep copy of the changes and sort by address.
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changes := validatorListCopy(origChanges)
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sort.Sort(ValidatorsByAddress(changes))
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removals = make([]*Validator, 0, len(changes))
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updates = make([]*Validator, 0, len(changes))
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var prevAddr Address
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// Scan changes by address and append valid validators to updates or removals lists.
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for _, valUpdate := range changes {
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if bytes.Equal(valUpdate.Address, prevAddr) {
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err = fmt.Errorf("duplicate entry %v in %v", valUpdate, changes)
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return nil, nil, err
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}
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if valUpdate.VotingPower < 0 {
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err = fmt.Errorf("voting power can't be negative: %v", valUpdate)
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return nil, nil, err
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}
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if valUpdate.VotingPower > MaxTotalVotingPower {
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err = fmt.Errorf("to prevent clipping/ overflow, voting power can't be higher than %v: %v ",
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MaxTotalVotingPower, valUpdate)
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return nil, nil, err
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}
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if valUpdate.VotingPower == 0 {
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removals = append(removals, valUpdate)
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} else {
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updates = append(updates, valUpdate)
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}
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prevAddr = valUpdate.Address
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}
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return updates, removals, err
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}
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// Verifies a list of updates against a validator set, making sure the allowed
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// total voting power would not be exceeded if these updates would be applied to the set.
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//
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// Returns:
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// updatedTotalVotingPower - the new total voting power if these updates would be applied
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// numNewValidators - number of new validators
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// err - non-nil if the maximum allowed total voting power would be exceeded
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//
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// 'updates' should be a list of proper validator changes, i.e. they have been verified
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// by processChanges for duplicates and invalid values.
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// No changes are made to the validator set 'vals'.
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func verifyUpdates(
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updates []*Validator,
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vals *ValidatorSet,
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) (updatedTotalVotingPower int64, numNewValidators int, err error) {
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updatedTotalVotingPower = vals.TotalVotingPower()
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for _, valUpdate := range updates {
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address := valUpdate.Address
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_, val := vals.GetByAddress(address)
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if val == nil {
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// New validator, add its voting power the the total.
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updatedTotalVotingPower += valUpdate.VotingPower
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numNewValidators++
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} else {
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// Updated validator, add the difference in power to the total.
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updatedTotalVotingPower += valUpdate.VotingPower - val.VotingPower
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}
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}
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overflow := updatedTotalVotingPower > MaxTotalVotingPower
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if overflow {
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err = fmt.Errorf(
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"failed to add/update validator, total voting power would exceed the max allowed %v",
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MaxTotalVotingPower)
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return 0, 0, err
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}
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return updatedTotalVotingPower, numNewValidators, nil
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}
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// Computes the proposer priority for the validators not present in the set based on 'updatedTotalVotingPower'.
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// Leaves unchanged the priorities of validators that are changed.
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//
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// 'updates' parameter must be a list of unique validators to be added or updated.
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// No changes are made to the validator set 'vals'.
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func computeNewPriorities(updates []*Validator, vals *ValidatorSet, updatedTotalVotingPower int64) {
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for _, valUpdate := range updates {
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address := valUpdate.Address
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_, val := vals.GetByAddress(address)
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if val == nil {
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// add val
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// Set ProposerPriority to -C*totalVotingPower (with C ~= 1.125) to make sure validators can't
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// un-bond and then re-bond to reset their (potentially previously negative) ProposerPriority to zero.
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//
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// Contract: updatedVotingPower < MaxTotalVotingPower to ensure ProposerPriority does
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// not exceed the bounds of int64.
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//
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// Compute ProposerPriority = -1.125*totalVotingPower == -(updatedVotingPower + (updatedVotingPower >> 3)).
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valUpdate.ProposerPriority = -(updatedTotalVotingPower + (updatedTotalVotingPower >> 3))
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} else {
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valUpdate.ProposerPriority = val.ProposerPriority
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}
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}
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}
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// Merges the vals' validator list with the updates list.
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// When two elements with same address are seen, the one from updates is selected.
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// Expects updates to be a list of updates sorted by address with no duplicates or errors,
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// must have been validated with verifyUpdates() and priorities computed with computeNewPriorities().
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func (vals *ValidatorSet) applyUpdates(updates []*Validator) {
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existing := vals.Validators
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merged := make([]*Validator, len(existing)+len(updates))
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i := 0
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for len(existing) > 0 && len(updates) > 0 {
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if bytes.Compare(existing[0].Address, updates[0].Address) < 0 { // unchanged validator
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merged[i] = existing[0]
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existing = existing[1:]
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} else {
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// Apply add or update.
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merged[i] = updates[0]
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if bytes.Equal(existing[0].Address, updates[0].Address) {
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// Validator is present in both, advance existing.
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existing = existing[1:]
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}
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updates = updates[1:]
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}
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i++
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}
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// Add the elements which are left.
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for j := 0; j < len(existing); j++ {
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merged[i] = existing[j]
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i++
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}
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// OR add updates which are left.
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for j := 0; j < len(updates); j++ {
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merged[i] = updates[j]
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i++
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}
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vals.Validators = merged[:i]
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}
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// Checks that the validators to be removed are part of the validator set.
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// No changes are made to the validator set 'vals'.
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func verifyRemovals(deletes []*Validator, vals *ValidatorSet) error {
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for _, valUpdate := range deletes {
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address := valUpdate.Address
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_, val := vals.GetByAddress(address)
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if val == nil {
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return fmt.Errorf("failed to find validator %X to remove", address)
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}
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}
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if len(deletes) > len(vals.Validators) {
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panic("more deletes than validators")
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}
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return nil
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}
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|
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// Removes the validators specified in 'deletes' from validator set 'vals'.
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// Should not fail as verification has been done before.
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func (vals *ValidatorSet) applyRemovals(deletes []*Validator) {
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existing := vals.Validators
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merged := make([]*Validator, len(existing)-len(deletes))
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i := 0
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|
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// Loop over deletes until we removed all of them.
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for len(deletes) > 0 {
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if bytes.Equal(existing[0].Address, deletes[0].Address) {
|
|
deletes = deletes[1:]
|
|
} else { // Leave it in the resulting slice.
|
|
merged[i] = existing[0]
|
|
i++
|
|
}
|
|
existing = existing[1:]
|
|
}
|
|
|
|
// Add the elements which are left.
|
|
for j := 0; j < len(existing); j++ {
|
|
merged[i] = existing[j]
|
|
i++
|
|
}
|
|
|
|
vals.Validators = merged[:i]
|
|
}
|
|
|
|
// Main function used by UpdateWithChangeSet() and NewValidatorSet().
|
|
// If 'allowDeletes' is false then delete operations (identified by validators with voting power 0)
|
|
// are not allowed and will trigger an error if present in 'changes'.
|
|
// The 'allowDeletes' flag is set to false by NewValidatorSet() and to true by UpdateWithChangeSet().
|
|
func (vals *ValidatorSet) updateWithChangeSet(changes []*Validator, allowDeletes bool) error {
|
|
|
|
if len(changes) == 0 {
|
|
return nil
|
|
}
|
|
|
|
// Check for duplicates within changes, split in 'updates' and 'deletes' lists (sorted).
|
|
updates, deletes, err := processChanges(changes)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if !allowDeletes && len(deletes) != 0 {
|
|
return fmt.Errorf("cannot process validators with voting power 0: %v", deletes)
|
|
}
|
|
|
|
// Verify that applying the 'deletes' against 'vals' will not result in error.
|
|
if err := verifyRemovals(deletes, vals); err != nil {
|
|
return err
|
|
}
|
|
|
|
// Verify that applying the 'updates' against 'vals' will not result in error.
|
|
updatedTotalVotingPower, numNewValidators, err := verifyUpdates(updates, vals)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// Check that the resulting set will not be empty.
|
|
if numNewValidators == 0 && len(vals.Validators) == len(deletes) {
|
|
return errors.New("applying the validator changes would result in empty set")
|
|
}
|
|
|
|
// Compute the priorities for updates.
|
|
computeNewPriorities(updates, vals, updatedTotalVotingPower)
|
|
|
|
// Apply updates and removals.
|
|
vals.applyUpdates(updates)
|
|
vals.applyRemovals(deletes)
|
|
|
|
vals.updateTotalVotingPower()
|
|
|
|
// Scale and center.
|
|
vals.RescalePriorities(PriorityWindowSizeFactor * vals.TotalVotingPower())
|
|
vals.shiftByAvgProposerPriority()
|
|
|
|
return nil
|
|
}
|
|
|
|
// UpdateWithChangeSet attempts to update the validator set with 'changes'.
|
|
// It performs the following steps:
|
|
// - validates the changes making sure there are no duplicates and splits them in updates and deletes
|
|
// - verifies that applying the changes will not result in errors
|
|
// - computes the total voting power BEFORE removals to ensure that in the next steps the priorities
|
|
// across old and newly added validators are fair
|
|
// - computes the priorities of new validators against the final set
|
|
// - applies the updates against the validator set
|
|
// - applies the removals against the validator set
|
|
// - performs scaling and centering of priority values
|
|
// If an error is detected during verification steps, it is returned and the validator set
|
|
// is not changed.
|
|
func (vals *ValidatorSet) UpdateWithChangeSet(changes []*Validator) error {
|
|
return vals.updateWithChangeSet(changes, true)
|
|
}
|
|
|
|
// Verify that +2/3 of the set had signed the given signBytes.
|
|
func (vals *ValidatorSet) VerifyCommit(chainID string, blockID BlockID, height int64, commit *Commit) error {
|
|
|
|
if err := commit.ValidateBasic(); err != nil {
|
|
return err
|
|
}
|
|
if vals.Size() != len(commit.Precommits) {
|
|
return NewErrInvalidCommitPrecommits(vals.Size(), len(commit.Precommits))
|
|
}
|
|
if height != commit.Height() {
|
|
return NewErrInvalidCommitHeight(height, commit.Height())
|
|
}
|
|
if !blockID.Equals(commit.BlockID) {
|
|
return fmt.Errorf("invalid commit -- wrong block id: want %v got %v",
|
|
blockID, commit.BlockID)
|
|
}
|
|
|
|
talliedVotingPower := int64(0)
|
|
|
|
for idx, precommit := range commit.Precommits {
|
|
if precommit == nil {
|
|
continue // OK, some precommits can be missing.
|
|
}
|
|
_, val := vals.GetByIndex(idx)
|
|
// Validate signature.
|
|
precommitSignBytes := commit.VoteSignBytes(chainID, idx)
|
|
if !val.PubKey.VerifyBytes(precommitSignBytes, precommit.Signature) {
|
|
return fmt.Errorf("invalid commit -- invalid signature: %v", precommit)
|
|
}
|
|
// Good precommit!
|
|
if blockID.Equals(precommit.BlockID) {
|
|
talliedVotingPower += val.VotingPower
|
|
}
|
|
// else {
|
|
// It's OK that the BlockID doesn't match. We include stray
|
|
// precommits to measure validator availability.
|
|
// }
|
|
}
|
|
|
|
if talliedVotingPower > vals.TotalVotingPower()*2/3 {
|
|
return nil
|
|
}
|
|
return errTooMuchChange{talliedVotingPower, vals.TotalVotingPower()*2/3 + 1}
|
|
}
|
|
|
|
// VerifyFutureCommit will check to see if the set would be valid with a different
|
|
// validator set.
|
|
//
|
|
// vals is the old validator set that we know. Over 2/3 of the power in old
|
|
// signed this block.
|
|
//
|
|
// In Tendermint, 1/3 of the voting power can halt or fork the chain, but 1/3
|
|
// can't make arbitrary state transitions. You still need > 2/3 Byzantine to
|
|
// make arbitrary state transitions.
|
|
//
|
|
// To preserve this property in the light client, we also require > 2/3 of the
|
|
// old vals to sign the future commit at H, that way we preserve the property
|
|
// that if they weren't being truthful about the validator set at H (block hash
|
|
// -> vals hash) or about the app state (block hash -> app hash) we can slash
|
|
// > 2/3. Otherwise, the lite client isn't providing the same security
|
|
// guarantees.
|
|
//
|
|
// Even if we added a slashing condition that if you sign a block header with
|
|
// the wrong validator set, then we would only need > 1/3 of signatures from
|
|
// the old vals on the new commit, it wouldn't be sufficient because the new
|
|
// vals can be arbitrary and commit some arbitrary app hash.
|
|
//
|
|
// newSet is the validator set that signed this block. Only votes from new are
|
|
// sufficient for 2/3 majority in the new set as well, for it to be a valid
|
|
// commit.
|
|
//
|
|
// NOTE: This doesn't check whether the commit is a future commit, because the
|
|
// current height isn't part of the ValidatorSet. Caller must check that the
|
|
// commit height is greater than the height for this validator set.
|
|
func (vals *ValidatorSet) VerifyFutureCommit(newSet *ValidatorSet, chainID string,
|
|
blockID BlockID, height int64, commit *Commit) error {
|
|
oldVals := vals
|
|
|
|
// Commit must be a valid commit for newSet.
|
|
err := newSet.VerifyCommit(chainID, blockID, height, commit)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
// Check old voting power.
|
|
oldVotingPower := int64(0)
|
|
seen := map[int]bool{}
|
|
round := commit.Round()
|
|
|
|
for idx, precommit := range commit.Precommits {
|
|
if precommit == nil {
|
|
continue
|
|
}
|
|
if precommit.Height != height {
|
|
return errors.Errorf("blocks don't match - %d vs %d", round, precommit.Round)
|
|
}
|
|
if precommit.Round != round {
|
|
return errors.Errorf("invalid commit -- wrong round: %v vs %v", round, precommit.Round)
|
|
}
|
|
if precommit.Type != PrecommitType {
|
|
return errors.Errorf("invalid commit -- not precommit @ index %v", idx)
|
|
}
|
|
// See if this validator is in oldVals.
|
|
oldIdx, val := oldVals.GetByAddress(precommit.ValidatorAddress)
|
|
if val == nil || seen[oldIdx] {
|
|
continue // missing or double vote...
|
|
}
|
|
seen[oldIdx] = true
|
|
|
|
// Validate signature.
|
|
precommitSignBytes := commit.VoteSignBytes(chainID, idx)
|
|
if !val.PubKey.VerifyBytes(precommitSignBytes, precommit.Signature) {
|
|
return errors.Errorf("invalid commit -- invalid signature: %v", precommit)
|
|
}
|
|
// Good precommit!
|
|
if blockID.Equals(precommit.BlockID) {
|
|
oldVotingPower += val.VotingPower
|
|
}
|
|
// else {
|
|
// It's OK that the BlockID doesn't match. We include stray
|
|
// precommits to measure validator availability.
|
|
// }
|
|
}
|
|
|
|
if oldVotingPower <= oldVals.TotalVotingPower()*2/3 {
|
|
return errTooMuchChange{oldVotingPower, oldVals.TotalVotingPower()*2/3 + 1}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
//-----------------
|
|
// ErrTooMuchChange
|
|
|
|
func IsErrTooMuchChange(err error) bool {
|
|
_, ok := errors.Cause(err).(errTooMuchChange)
|
|
return ok
|
|
}
|
|
|
|
type errTooMuchChange struct {
|
|
got int64
|
|
needed int64
|
|
}
|
|
|
|
func (e errTooMuchChange) Error() string {
|
|
return fmt.Sprintf("Invalid commit -- insufficient old voting power: got %v, needed %v", e.got, e.needed)
|
|
}
|
|
|
|
//----------------
|
|
|
|
func (vals *ValidatorSet) String() string {
|
|
return vals.StringIndented("")
|
|
}
|
|
|
|
// String
|
|
func (vals *ValidatorSet) StringIndented(indent string) string {
|
|
if vals == nil {
|
|
return "nil-ValidatorSet"
|
|
}
|
|
var valStrings []string
|
|
vals.Iterate(func(index int, val *Validator) bool {
|
|
valStrings = append(valStrings, val.String())
|
|
return false
|
|
})
|
|
return fmt.Sprintf(`ValidatorSet{
|
|
%s Proposer: %v
|
|
%s Validators:
|
|
%s %v
|
|
%s}`,
|
|
indent, vals.GetProposer().String(),
|
|
indent,
|
|
indent, strings.Join(valStrings, "\n"+indent+" "),
|
|
indent)
|
|
|
|
}
|
|
|
|
//-------------------------------------
|
|
// Implements sort for sorting validators by address.
|
|
|
|
// Sort validators by address.
|
|
type ValidatorsByAddress []*Validator
|
|
|
|
func (valz ValidatorsByAddress) Len() int {
|
|
return len(valz)
|
|
}
|
|
|
|
func (valz ValidatorsByAddress) Less(i, j int) bool {
|
|
return bytes.Compare(valz[i].Address, valz[j].Address) == -1
|
|
}
|
|
|
|
func (valz ValidatorsByAddress) Swap(i, j int) {
|
|
it := valz[i]
|
|
valz[i] = valz[j]
|
|
valz[j] = it
|
|
}
|
|
|
|
//----------------------------------------
|
|
// for testing
|
|
|
|
// RandValidatorSet returns a randomized validator set, useful for testing.
|
|
// NOTE: PrivValidator are in order.
|
|
// UNSTABLE
|
|
func RandValidatorSet(numValidators int, votingPower int64) (*ValidatorSet, []PrivValidator) {
|
|
valz := make([]*Validator, numValidators)
|
|
privValidators := make([]PrivValidator, numValidators)
|
|
for i := 0; i < numValidators; i++ {
|
|
val, privValidator := RandValidator(false, votingPower)
|
|
valz[i] = val
|
|
privValidators[i] = privValidator
|
|
}
|
|
vals := NewValidatorSet(valz)
|
|
sort.Sort(PrivValidatorsByAddress(privValidators))
|
|
return vals, privValidators
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
// safe addition/subtraction
|
|
|
|
func safeAdd(a, b int64) (int64, bool) {
|
|
if b > 0 && a > math.MaxInt64-b {
|
|
return -1, true
|
|
} else if b < 0 && a < math.MinInt64-b {
|
|
return -1, true
|
|
}
|
|
return a + b, false
|
|
}
|
|
|
|
func safeSub(a, b int64) (int64, bool) {
|
|
if b > 0 && a < math.MinInt64+b {
|
|
return -1, true
|
|
} else if b < 0 && a > math.MaxInt64+b {
|
|
return -1, true
|
|
}
|
|
return a - b, false
|
|
}
|
|
|
|
func safeAddClip(a, b int64) int64 {
|
|
c, overflow := safeAdd(a, b)
|
|
if overflow {
|
|
if b < 0 {
|
|
return math.MinInt64
|
|
}
|
|
return math.MaxInt64
|
|
}
|
|
return c
|
|
}
|
|
|
|
func safeSubClip(a, b int64) int64 {
|
|
c, overflow := safeSub(a, b)
|
|
if overflow {
|
|
if b > 0 {
|
|
return math.MinInt64
|
|
}
|
|
return math.MaxInt64
|
|
}
|
|
return c
|
|
}
|