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bor.go
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bor.go
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package bor
import (
"bytes"
"context"
"encoding/hex"
"encoding/json"
"errors"
"fmt"
"io"
"math/big"
"sort"
"strconv"
"sync"
"sync/atomic"
"time"
lru "github.com/hashicorp/golang-lru"
"golang.org/x/crypto/sha3"
"github.com/ethereum/go-ethereum/accounts"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/consensus"
"github.com/ethereum/go-ethereum/consensus/bor/api"
"github.com/ethereum/go-ethereum/consensus/bor/clerk"
"github.com/ethereum/go-ethereum/consensus/bor/heimdall/span"
"github.com/ethereum/go-ethereum/consensus/bor/statefull"
"github.com/ethereum/go-ethereum/consensus/bor/valset"
"github.com/ethereum/go-ethereum/consensus/misc"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/state"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/params"
"github.com/ethereum/go-ethereum/rlp"
"github.com/ethereum/go-ethereum/rpc"
"github.com/ethereum/go-ethereum/trie"
)
const (
checkpointInterval = 1024 // Number of blocks after which to save the vote snapshot to the database
inmemorySnapshots = 128 // Number of recent vote snapshots to keep in memory
inmemorySignatures = 4096 // Number of recent block signatures to keep in memory
)
// Bor protocol constants.
var (
defaultSprintLength = uint64(64) // Default number of blocks after which to checkpoint and reset the pending votes
extraVanity = 32 // Fixed number of extra-data prefix bytes reserved for signer vanity
extraSeal = 65 // Fixed number of extra-data suffix bytes reserved for signer seal
uncleHash = types.CalcUncleHash(nil) // Always Keccak256(RLP([])) as uncles are meaningless outside of PoW.
validatorHeaderBytesLength = common.AddressLength + 20 // address + power
)
// Various error messages to mark blocks invalid. These should be private to
// prevent engine specific errors from being referenced in the remainder of the
// codebase, inherently breaking if the engine is swapped out. Please put common
// error types into the consensus package.
var (
// errUnknownBlock is returned when the list of signers is requested for a block
// that is not part of the local blockchain.
errUnknownBlock = errors.New("unknown block")
// errMissingVanity is returned if a block's extra-data section is shorter than
// 32 bytes, which is required to store the signer vanity.
errMissingVanity = errors.New("extra-data 32 byte vanity prefix missing")
// errMissingSignature is returned if a block's extra-data section doesn't seem
// to contain a 65 byte secp256k1 signature.
errMissingSignature = errors.New("extra-data 65 byte signature suffix missing")
// errExtraValidators is returned if non-sprint-end block contain validator data in
// their extra-data fields.
errExtraValidators = errors.New("non-sprint-end block contains extra validator list")
// errInvalidSpanValidators is returned if a block contains an
// invalid list of validators (i.e. non divisible by 40 bytes).
errInvalidSpanValidators = errors.New("invalid validator list on sprint end block")
// errInvalidMixDigest is returned if a block's mix digest is non-zero.
errInvalidMixDigest = errors.New("non-zero mix digest")
// errInvalidUncleHash is returned if a block contains an non-empty uncle list.
errInvalidUncleHash = errors.New("non empty uncle hash")
// errInvalidDifficulty is returned if the difficulty of a block neither 1 or 2.
errInvalidDifficulty = errors.New("invalid difficulty")
// ErrInvalidTimestamp is returned if the timestamp of a block is lower than
// the previous block's timestamp + the minimum block period.
ErrInvalidTimestamp = errors.New("invalid timestamp")
// errOutOfRangeChain is returned if an authorization list is attempted to
// be modified via out-of-range or non-contiguous headers.
errOutOfRangeChain = errors.New("out of range or non-contiguous chain")
errUncleDetected = errors.New("uncles not allowed")
errUnknownValidators = errors.New("unknown validators")
)
// SignerFn is a signer callback function to request a header to be signed by a
// backing account.
type SignerFn func(accounts.Account, string, []byte) ([]byte, error)
// ecrecover extracts the Ethereum account address from a signed header.
func ecrecover(header *types.Header, sigcache *lru.ARCCache, c *params.BorConfig) (common.Address, error) {
// If the signature's already cached, return that
hash := header.Hash()
if address, known := sigcache.Get(hash); known {
return address.(common.Address), nil
}
// Retrieve the signature from the header extra-data
if len(header.Extra) < extraSeal {
return common.Address{}, errMissingSignature
}
signature := header.Extra[len(header.Extra)-extraSeal:]
// Recover the public key and the Ethereum address
pubkey, err := crypto.Ecrecover(SealHash(header, c).Bytes(), signature)
if err != nil {
return common.Address{}, err
}
var signer common.Address
copy(signer[:], crypto.Keccak256(pubkey[1:])[12:])
sigcache.Add(hash, signer)
return signer, nil
}
// SealHash returns the hash of a block prior to it being sealed.
func SealHash(header *types.Header, c *params.BorConfig) (hash common.Hash) {
hasher := sha3.NewLegacyKeccak256()
encodeSigHeader(hasher, header, c)
hasher.Sum(hash[:0])
return hash
}
func encodeSigHeader(w io.Writer, header *types.Header, c *params.BorConfig) {
enc := []interface{}{
header.ParentHash,
header.UncleHash,
header.Coinbase,
header.Root,
header.TxHash,
header.ReceiptHash,
header.Bloom,
header.Difficulty,
header.Number,
header.GasLimit,
header.GasUsed,
header.Time,
header.Extra[:len(header.Extra)-65], // Yes, this will panic if extra is too short
header.MixDigest,
header.Nonce,
}
if c.IsJaipur(header.Number.Uint64()) {
if header.BaseFee != nil {
enc = append(enc, header.BaseFee)
}
}
if err := rlp.Encode(w, enc); err != nil {
panic("can't encode: " + err.Error())
}
}
// CalcProducerDelay is the block delay algorithm based on block time, period, producerDelay and turn-ness of a signer
func CalcProducerDelay(number uint64, succession int, c *params.BorConfig) uint64 {
// When the block is the first block of the sprint, it is expected to be delayed by `producerDelay`.
// That is to allow time for block propagation in the last sprint
delay := c.CalculatePeriod(number)
if number%c.Sprint == 0 {
delay = c.ProducerDelay
}
if succession > 0 {
delay += uint64(succession) * c.CalculateBackupMultiplier(number)
}
return delay
}
// BorRLP returns the rlp bytes which needs to be signed for the bor
// sealing. The RLP to sign consists of the entire header apart from the 65 byte signature
// contained at the end of the extra data.
//
// Note, the method requires the extra data to be at least 65 bytes, otherwise it
// panics. This is done to avoid accidentally using both forms (signature present
// or not), which could be abused to produce different hashes for the same header.
func BorRLP(header *types.Header, c *params.BorConfig) []byte {
b := new(bytes.Buffer)
encodeSigHeader(b, header, c)
return b.Bytes()
}
// Bor is the matic-bor consensus engine
type Bor struct {
chainConfig *params.ChainConfig // Chain config
config *params.BorConfig // Consensus engine configuration parameters for bor consensus
db ethdb.Database // Database to store and retrieve snapshot checkpoints
recents *lru.ARCCache // Snapshots for recent block to speed up reorgs
signatures *lru.ARCCache // Signatures of recent blocks to speed up mining
authorizedSigner atomic.Pointer[signer] // Ethereum address and sign function of the signing key
ethAPI api.Caller
spanner Spanner
GenesisContractsClient GenesisContract
HeimdallClient IHeimdallClient
// The fields below are for testing only
fakeDiff bool // Skip difficulty verifications
closeOnce sync.Once
}
type signer struct {
signer common.Address // Ethereum address of the signing key
signFn SignerFn // Signer function to authorize hashes with
}
// New creates a Matic Bor consensus engine.
func New(
chainConfig *params.ChainConfig,
db ethdb.Database,
ethAPI api.Caller,
spanner Spanner,
heimdallClient IHeimdallClient,
genesisContracts GenesisContract,
) *Bor {
// get bor config
borConfig := chainConfig.Bor
// Set any missing consensus parameters to their defaults
if borConfig != nil && borConfig.Sprint == 0 {
borConfig.Sprint = defaultSprintLength
}
// Allocate the snapshot caches and create the engine
recents, _ := lru.NewARC(inmemorySnapshots)
signatures, _ := lru.NewARC(inmemorySignatures)
c := &Bor{
chainConfig: chainConfig,
config: borConfig,
db: db,
ethAPI: ethAPI,
recents: recents,
signatures: signatures,
spanner: spanner,
GenesisContractsClient: genesisContracts,
HeimdallClient: heimdallClient,
}
c.authorizedSigner.Store(&signer{
common.Address{},
func(_ accounts.Account, _ string, i []byte) ([]byte, error) {
// return an error to prevent panics
return nil, &UnauthorizedSignerError{0, common.Address{}.Bytes()}
},
})
// make sure we can decode all the GenesisAlloc in the BorConfig.
for key, genesisAlloc := range c.config.BlockAlloc {
if _, err := decodeGenesisAlloc(genesisAlloc); err != nil {
panic(fmt.Sprintf("BUG: Block alloc '%s' in genesis is not correct: %v", key, err))
}
}
return c
}
// Author implements consensus.Engine, returning the Ethereum address recovered
// from the signature in the header's extra-data section.
func (c *Bor) Author(header *types.Header) (common.Address, error) {
return ecrecover(header, c.signatures, c.config)
}
// VerifyHeader checks whether a header conforms to the consensus rules.
func (c *Bor) VerifyHeader(chain consensus.ChainHeaderReader, header *types.Header, _ bool) error {
return c.verifyHeader(chain, header, nil)
}
// VerifyHeaders is similar to VerifyHeader, but verifies a batch of headers. The
// method returns a quit channel to abort the operations and a results channel to
// retrieve the async verifications (the order is that of the input slice).
func (c *Bor) VerifyHeaders(chain consensus.ChainHeaderReader, headers []*types.Header, _ []bool) (chan<- struct{}, <-chan error) {
abort := make(chan struct{})
results := make(chan error, len(headers))
go func() {
for i, header := range headers {
err := c.verifyHeader(chain, header, headers[:i])
select {
case <-abort:
return
case results <- err:
}
}
}()
return abort, results
}
// verifyHeader checks whether a header conforms to the consensus rules.The
// caller may optionally pass in a batch of parents (ascending order) to avoid
// looking those up from the database. This is useful for concurrently verifying
// a batch of new headers.
func (c *Bor) verifyHeader(chain consensus.ChainHeaderReader, header *types.Header, parents []*types.Header) error {
if header.Number == nil {
return errUnknownBlock
}
number := header.Number.Uint64()
// Don't waste time checking blocks from the future
if header.Time > uint64(time.Now().Unix()) {
return consensus.ErrFutureBlock
}
if err := validateHeaderExtraField(header.Extra); err != nil {
return err
}
// check extr adata
isSprintEnd := IsSprintStart(number+1, c.config.Sprint)
// Ensure that the extra-data contains a signer list on checkpoint, but none otherwise
signersBytes := len(header.Extra) - extraVanity - extraSeal
if !isSprintEnd && signersBytes != 0 {
return errExtraValidators
}
if isSprintEnd && signersBytes%validatorHeaderBytesLength != 0 {
return errInvalidSpanValidators
}
// Ensure that the mix digest is zero as we don't have fork protection currently
if header.MixDigest != (common.Hash{}) {
return errInvalidMixDigest
}
// Ensure that the block doesn't contain any uncles which are meaningless in PoA
if header.UncleHash != uncleHash {
return errInvalidUncleHash
}
// Ensure that the block's difficulty is meaningful (may not be correct at this point)
if number > 0 {
if header.Difficulty == nil {
return errInvalidDifficulty
}
}
// Verify that the gas limit is <= 2^63-1
gasCap := uint64(0x7fffffffffffffff)
if header.GasLimit > gasCap {
return fmt.Errorf("invalid gasLimit: have %v, max %v", header.GasLimit, gasCap)
}
// If all checks passed, validate any special fields for hard forks
if err := misc.VerifyForkHashes(chain.Config(), header, false); err != nil {
return err
}
// All basic checks passed, verify cascading fields
return c.verifyCascadingFields(chain, header, parents)
}
// validateHeaderExtraField validates that the extra-data contains both the vanity and signature.
// header.Extra = header.Vanity + header.ProducerBytes (optional) + header.Seal
func validateHeaderExtraField(extraBytes []byte) error {
if len(extraBytes) < extraVanity {
return errMissingVanity
}
if len(extraBytes) < extraVanity+extraSeal {
return errMissingSignature
}
return nil
}
// verifyCascadingFields verifies all the header fields that are not standalone,
// rather depend on a batch of previous headers. The caller may optionally pass
// in a batch of parents (ascending order) to avoid looking those up from the
// database. This is useful for concurrently verifying a batch of new headers.
func (c *Bor) verifyCascadingFields(chain consensus.ChainHeaderReader, header *types.Header, parents []*types.Header) error {
// The genesis block is the always valid dead-end
number := header.Number.Uint64()
if number == 0 {
return nil
}
// Ensure that the block's timestamp isn't too close to it's parent
var parent *types.Header
if len(parents) > 0 {
parent = parents[len(parents)-1]
} else {
parent = chain.GetHeader(header.ParentHash, number-1)
}
if parent == nil || parent.Number.Uint64() != number-1 || parent.Hash() != header.ParentHash {
return consensus.ErrUnknownAncestor
}
// Verify that the gasUsed is <= gasLimit
if header.GasUsed > header.GasLimit {
return fmt.Errorf("invalid gasUsed: have %d, gasLimit %d", header.GasUsed, header.GasLimit)
}
if !chain.Config().IsLondon(header.Number) {
// Verify BaseFee not present before EIP-1559 fork.
if header.BaseFee != nil {
return fmt.Errorf("invalid baseFee before fork: have %d, want <nil>", header.BaseFee)
}
if err := misc.VerifyGaslimit(parent.GasLimit, header.GasLimit); err != nil {
return err
}
} else if err := misc.VerifyEip1559Header(chain.Config(), parent, header); err != nil {
// Verify the header's EIP-1559 attributes.
return err
}
if parent.Time+c.config.CalculatePeriod(number) > header.Time {
return ErrInvalidTimestamp
}
// Retrieve the snapshot needed to verify this header and cache it
snap, err := c.snapshot(chain, number-1, header.ParentHash, parents)
if err != nil {
return err
}
// verify the validator list in the last sprint block
if IsSprintStart(number, c.config.Sprint) {
parentValidatorBytes := parent.Extra[extraVanity : len(parent.Extra)-extraSeal]
validatorsBytes := make([]byte, len(snap.ValidatorSet.Validators)*validatorHeaderBytesLength)
currentValidators := snap.ValidatorSet.Copy().Validators
// sort validator by address
sort.Sort(valset.ValidatorsByAddress(currentValidators))
for i, validator := range currentValidators {
copy(validatorsBytes[i*validatorHeaderBytesLength:], validator.HeaderBytes())
}
// len(header.Extra) >= extraVanity+extraSeal has already been validated in validateHeaderExtraField, so this won't result in a panic
if !bytes.Equal(parentValidatorBytes, validatorsBytes) {
return &MismatchingValidatorsError{number - 1, validatorsBytes, parentValidatorBytes}
}
}
// All basic checks passed, verify the seal and return
return c.verifySeal(chain, header, parents)
}
// snapshot retrieves the authorization snapshot at a given point in time.
// nolint: gocognit
func (c *Bor) snapshot(chain consensus.ChainHeaderReader, number uint64, hash common.Hash, parents []*types.Header) (*Snapshot, error) {
// Search for a snapshot in memory or on disk for checkpoints
var snap *Snapshot
headers := make([]*types.Header, 0, 16)
//nolint:govet
for snap == nil {
// If an in-memory snapshot was found, use that
if s, ok := c.recents.Get(hash); ok {
snap = s.(*Snapshot)
break
}
// If an on-disk checkpoint snapshot can be found, use that
if number%checkpointInterval == 0 {
if s, err := loadSnapshot(c.config, c.signatures, c.db, hash); err == nil {
log.Trace("Loaded snapshot from disk", "number", number, "hash", hash)
snap = s
break
}
}
// If we're at the genesis, snapshot the initial state. Alternatively if we're
// at a checkpoint block without a parent (light client CHT), or we have piled
// up more headers than allowed to be reorged (chain reinit from a freezer),
// consider the checkpoint trusted and snapshot it.
// TODO fix this
// nolint:nestif
if number == 0 {
checkpoint := chain.GetHeaderByNumber(number)
if checkpoint != nil {
// get checkpoint data
hash := checkpoint.Hash()
// get validators and current span
validators, err := c.spanner.GetCurrentValidators(context.Background(), hash, number+1)
if err != nil {
return nil, err
}
// new snap shot
snap = newSnapshot(c.config, c.signatures, number, hash, validators)
if err := snap.store(c.db); err != nil {
return nil, err
}
log.Info("Stored checkpoint snapshot to disk", "number", number, "hash", hash)
break
}
}
// No snapshot for this header, gather the header and move backward
var header *types.Header
if len(parents) > 0 {
// If we have explicit parents, pick from there (enforced)
header = parents[len(parents)-1]
if header.Hash() != hash || header.Number.Uint64() != number {
return nil, consensus.ErrUnknownAncestor
}
parents = parents[:len(parents)-1]
} else {
// No explicit parents (or no more left), reach out to the database
header = chain.GetHeader(hash, number)
if header == nil {
return nil, consensus.ErrUnknownAncestor
}
}
headers = append(headers, header)
number, hash = number-1, header.ParentHash
}
log.Info("Snapshot has been found in", "headers depth", len(headers))
// check if snapshot is nil
if snap == nil {
return nil, fmt.Errorf("unknown error while retrieving snapshot at block number %v", number)
}
// Previous snapshot found, apply any pending headers on top of it
for i := 0; i < len(headers)/2; i++ {
headers[i], headers[len(headers)-1-i] = headers[len(headers)-1-i], headers[i]
}
snap, err := snap.apply(headers)
if err != nil {
return nil, err
}
c.recents.Add(snap.Hash, snap)
// If we've generated a new checkpoint snapshot, save to disk
if snap.Number%checkpointInterval == 0 && len(headers) > 0 {
if err = snap.store(c.db); err != nil {
return nil, err
}
log.Trace("Stored snapshot to disk", "number", snap.Number, "hash", snap.Hash)
}
return snap, err
}
// VerifyUncles implements consensus.Engine, always returning an error for any
// uncles as this consensus mechanism doesn't permit uncles.
func (c *Bor) VerifyUncles(_ consensus.ChainReader, block *types.Block) error {
if len(block.Uncles()) > 0 {
return errUncleDetected
}
return nil
}
// VerifySeal implements consensus.Engine, checking whether the signature contained
// in the header satisfies the consensus protocol requirements.
func (c *Bor) VerifySeal(chain consensus.ChainHeaderReader, header *types.Header) error {
return c.verifySeal(chain, header, nil)
}
// verifySeal checks whether the signature contained in the header satisfies the
// consensus protocol requirements. The method accepts an optional list of parent
// headers that aren't yet part of the local blockchain to generate the snapshots
// from.
func (c *Bor) verifySeal(chain consensus.ChainHeaderReader, header *types.Header, parents []*types.Header) error {
// Verifying the genesis block is not supported
number := header.Number.Uint64()
if number == 0 {
return errUnknownBlock
}
// Retrieve the snapshot needed to verify this header and cache it
snap, err := c.snapshot(chain, number-1, header.ParentHash, parents)
if err != nil {
return err
}
// Resolve the authorization key and check against signers
signer, err := ecrecover(header, c.signatures, c.config)
if err != nil {
return err
}
if !snap.ValidatorSet.HasAddress(signer) {
// Check the UnauthorizedSignerError.Error() msg to see why we pass number-1
return &UnauthorizedSignerError{number - 1, signer.Bytes()}
}
succession, err := snap.GetSignerSuccessionNumber(signer)
if err != nil {
return err
}
var parent *types.Header
if len(parents) > 0 { // if parents is nil, len(parents) is zero
parent = parents[len(parents)-1]
} else if number > 0 {
parent = chain.GetHeader(header.ParentHash, number-1)
}
if IsBlockOnTime(parent, header, number, succession, c.config) {
return &BlockTooSoonError{number, succession}
}
// Ensure that the difficulty corresponds to the turn-ness of the signer
if !c.fakeDiff {
difficulty := Difficulty(snap.ValidatorSet, signer)
if header.Difficulty.Uint64() != difficulty {
return &WrongDifficultyError{number, difficulty, header.Difficulty.Uint64(), signer.Bytes()}
}
}
return nil
}
func IsBlockOnTime(parent *types.Header, header *types.Header, number uint64, succession int, cfg *params.BorConfig) bool {
return parent != nil && header.Time < parent.Time+CalcProducerDelay(number, succession, cfg)
}
// Prepare implements consensus.Engine, preparing all the consensus fields of the
// header for running the transactions on top.
func (c *Bor) Prepare(chain consensus.ChainHeaderReader, header *types.Header) error {
// If the block isn't a checkpoint, cast a random vote (good enough for now)
header.Coinbase = common.Address{}
header.Nonce = types.BlockNonce{}
number := header.Number.Uint64()
// Assemble the validator snapshot to check which votes make sense
snap, err := c.snapshot(chain, number-1, header.ParentHash, nil)
if err != nil {
return err
}
currentSigner := *c.authorizedSigner.Load()
// Set the correct difficulty
header.Difficulty = new(big.Int).SetUint64(Difficulty(snap.ValidatorSet, currentSigner.signer))
// Ensure the extra data has all it's components
if len(header.Extra) < extraVanity {
header.Extra = append(header.Extra, bytes.Repeat([]byte{0x00}, extraVanity-len(header.Extra))...)
}
header.Extra = header.Extra[:extraVanity]
// get validator set if number
if IsSprintStart(number+1, c.config.Sprint) {
newValidators, err := c.spanner.GetCurrentValidators(context.Background(), header.ParentHash, number+1)
if err != nil {
return errUnknownValidators
}
// sort validator by address
sort.Sort(valset.ValidatorsByAddress(newValidators))
for _, validator := range newValidators {
header.Extra = append(header.Extra, validator.HeaderBytes()...)
}
}
// add extra seal space
header.Extra = append(header.Extra, make([]byte, extraSeal)...)
// Mix digest is reserved for now, set to empty
header.MixDigest = common.Hash{}
// Ensure the timestamp has the correct delay
parent := chain.GetHeader(header.ParentHash, number-1)
if parent == nil {
return consensus.ErrUnknownAncestor
}
var succession int
// if signer is not empty
if currentSigner.signer != (common.Address{}) {
succession, err = snap.GetSignerSuccessionNumber(currentSigner.signer)
if err != nil {
return err
}
}
header.Time = parent.Time + CalcProducerDelay(number, succession, c.config)
if header.Time < uint64(time.Now().Unix()) {
header.Time = uint64(time.Now().Unix())
}
return nil
}
// Finalize implements consensus.Engine, ensuring no uncles are set, nor block
// rewards given.
func (c *Bor) Finalize(chain consensus.ChainHeaderReader, header *types.Header, state *state.StateDB, _ []*types.Transaction, _ []*types.Header) {
var (
stateSyncData []*types.StateSyncData
err error
)
headerNumber := header.Number.Uint64()
if IsSprintStart(headerNumber, c.config.Sprint) {
ctx := context.Background()
cx := statefull.ChainContext{Chain: chain, Bor: c}
// check and commit span
if err := c.checkAndCommitSpan(ctx, state, header, cx); err != nil {
log.Error("Error while committing span", "error", err)
return
}
if c.HeimdallClient != nil {
// commit states
stateSyncData, err = c.CommitStates(ctx, state, header, cx)
if err != nil {
log.Error("Error while committing states", "error", err)
return
}
}
}
if err = c.changeContractCodeIfNeeded(headerNumber, state); err != nil {
log.Error("Error changing contract code", "error", err)
return
}
// No block rewards in PoA, so the state remains as is and uncles are dropped
header.Root = state.IntermediateRoot(chain.Config().IsEIP158(header.Number))
header.UncleHash = types.CalcUncleHash(nil)
// Set state sync data to blockchain
bc := chain.(*core.BlockChain)
bc.SetStateSync(stateSyncData)
}
func decodeGenesisAlloc(i interface{}) (core.GenesisAlloc, error) {
var alloc core.GenesisAlloc
b, err := json.Marshal(i)
if err != nil {
return nil, err
}
if err := json.Unmarshal(b, &alloc); err != nil {
return nil, err
}
return alloc, nil
}
func (c *Bor) changeContractCodeIfNeeded(headerNumber uint64, state *state.StateDB) error {
for blockNumber, genesisAlloc := range c.config.BlockAlloc {
if blockNumber == strconv.FormatUint(headerNumber, 10) {
allocs, err := decodeGenesisAlloc(genesisAlloc)
if err != nil {
return fmt.Errorf("failed to decode genesis alloc: %w", err)
}
for addr, account := range allocs {
log.Info("change contract code", "address", addr)
state.SetCode(addr, account.Code)
}
}
}
return nil
}
// FinalizeAndAssemble implements consensus.Engine, ensuring no uncles are set,
// nor block rewards given, and returns the final block.
func (c *Bor) FinalizeAndAssemble(chain consensus.ChainHeaderReader, header *types.Header, state *state.StateDB, txs []*types.Transaction, _ []*types.Header, receipts []*types.Receipt) (*types.Block, error) {
var stateSyncData []*types.StateSyncData
headerNumber := header.Number.Uint64()
if IsSprintStart(headerNumber, c.config.Sprint) {
ctx := context.Background()
cx := statefull.ChainContext{Chain: chain, Bor: c}
// check and commit span
err := c.checkAndCommitSpan(ctx, state, header, cx)
if err != nil {
log.Error("Error while committing span", "error", err)
return nil, err
}
if c.HeimdallClient != nil {
// commit states
stateSyncData, err = c.CommitStates(ctx, state, header, cx)
if err != nil {
log.Error("Error while committing states", "error", err)
return nil, err
}
}
}
if err := c.changeContractCodeIfNeeded(headerNumber, state); err != nil {
log.Error("Error changing contract code", "error", err)
return nil, err
}
// No block rewards in PoA, so the state remains as is and uncles are dropped
header.Root = state.IntermediateRoot(chain.Config().IsEIP158(header.Number))
header.UncleHash = types.CalcUncleHash(nil)
// Assemble block
block := types.NewBlock(header, txs, nil, receipts, new(trie.Trie))
// set state sync
bc := chain.(core.BorStateSyncer)
bc.SetStateSync(stateSyncData)
// return the final block for sealing
return block, nil
}
// Authorize injects a private key into the consensus engine to mint new blocks
// with.
func (c *Bor) Authorize(currentSigner common.Address, signFn SignerFn) {
c.authorizedSigner.Store(&signer{
signer: currentSigner,
signFn: signFn,
})
}
// Seal implements consensus.Engine, attempting to create a sealed block using
// the local signing credentials.
func (c *Bor) Seal(chain consensus.ChainHeaderReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error {
header := block.Header()
// Sealing the genesis block is not supported
number := header.Number.Uint64()
if number == 0 {
return errUnknownBlock
}
// For 0-period chains, refuse to seal empty blocks (no reward but would spin sealing)
if c.config.CalculatePeriod(number) == 0 && len(block.Transactions()) == 0 {
log.Info("Sealing paused, waiting for transactions")
return nil
}
// Don't hold the signer fields for the entire sealing procedure
currentSigner := *c.authorizedSigner.Load()
snap, err := c.snapshot(chain, number-1, header.ParentHash, nil)
if err != nil {
return err
}
// Bail out if we're unauthorized to sign a block
if !snap.ValidatorSet.HasAddress(currentSigner.signer) {
// Check the UnauthorizedSignerError.Error() msg to see why we pass number-1
return &UnauthorizedSignerError{number - 1, currentSigner.signer.Bytes()}
}
successionNumber, err := snap.GetSignerSuccessionNumber(currentSigner.signer)
if err != nil {
return err
}
// Sweet, the protocol permits us to sign the block, wait for our time
delay := time.Unix(int64(header.Time), 0).Sub(time.Now()) // nolint: gosimple
// wiggle was already accounted for in header.Time, this is just for logging
wiggle := time.Duration(successionNumber) * time.Duration(c.config.CalculateBackupMultiplier(number)) * time.Second
// Sign all the things!
err = Sign(currentSigner.signFn, currentSigner.signer, header, c.config)
if err != nil {
return err
}
// Wait until sealing is terminated or delay timeout.
log.Info("Waiting for slot to sign and propagate", "number", number, "hash", header.Hash, "delay-in-sec", uint(delay), "delay", common.PrettyDuration(delay))
go func() {
select {
case <-stop:
log.Debug("Discarding sealing operation for block", "number", number)
return
case <-time.After(delay):
if wiggle > 0 {
log.Info(
"Sealing out-of-turn",
"number", number,
"hash", header.Hash,
"wiggle-in-sec", uint(wiggle),
"wiggle", common.PrettyDuration(wiggle),
"in-turn-signer", snap.ValidatorSet.GetProposer().Address.Hex(),
)
}
log.Info(
"Sealing successful",
"number", number,
"delay", delay,
"headerDifficulty", header.Difficulty,
)
}
select {
case results <- block.WithSeal(header):
default:
log.Warn("Sealing result was not read by miner", "number", number, "sealhash", SealHash(header, c.config))
}
}()
return nil
}
func Sign(signFn SignerFn, signer common.Address, header *types.Header, c *params.BorConfig) error {
sighash, err := signFn(accounts.Account{Address: signer}, accounts.MimetypeBor, BorRLP(header, c))
if err != nil {
return err
}
copy(header.Extra[len(header.Extra)-extraSeal:], sighash)
return nil
}
// CalcDifficulty is the difficulty adjustment algorithm. It returns the difficulty
// that a new block should have based on the previous blocks in the chain and the
// current signer.
func (c *Bor) CalcDifficulty(chain consensus.ChainHeaderReader, _ uint64, parent *types.Header) *big.Int {
snap, err := c.snapshot(chain, parent.Number.Uint64(), parent.Hash(), nil)
if err != nil {
return nil
}
return new(big.Int).SetUint64(Difficulty(snap.ValidatorSet, c.authorizedSigner.Load().signer))
}
// SealHash returns the hash of a block prior to it being sealed.
func (c *Bor) SealHash(header *types.Header) common.Hash {
return SealHash(header, c.config)
}
// APIs implements consensus.Engine, returning the user facing RPC API to allow
// controlling the signer voting.
func (c *Bor) APIs(chain consensus.ChainHeaderReader) []rpc.API {
return []rpc.API{{
Namespace: "bor",
Version: "1.0",
Service: &API{chain: chain, bor: c},
Public: false,
}}
}
// Close implements consensus.Engine. It's a noop for bor as there are no background threads.
func (c *Bor) Close() error {
c.closeOnce.Do(func() {
if c.HeimdallClient != nil {
c.HeimdallClient.Close()
}
})
return nil
}
func (c *Bor) checkAndCommitSpan(
ctx context.Context,
state *state.StateDB,
header *types.Header,