// SetCurrentHeader sets the current head header of the canonical chain.
func (hc *HeaderChain) SetCurrentHeader(head *types.Header) {
if err := WriteHeadHeaderHash(hc.chainDb, head.Hash()); err != nil {
glog.Fatalf("failed to insert head header hash: %v", err)
}
hc.currentHeader = head
hc.currentHeaderHash = head.Hash()
}
// WriteHeader writes a header into the local chain, given that its parent is
// already known. If the total difficulty of the newly inserted header becomes
// greater than the current known TD, the canonical chain is re-routed.
//
// Note: This method is not concurrent-safe with inserting blocks simultaneously
// into the chain, as side effects caused by reorganisations cannot be emulated
// without the real blocks. Hence, writing headers directly should only be done
// in two scenarios: pure-header mode of operation (light clients), or properly
// separated header/block phases (non-archive clients).
func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, err error) {
// Cache some values to prevent constant recalculation
var (
hash = header.Hash()
number = header.Number.Uint64()
)
// Calculate the total difficulty of the header
ptd := hc.GetTd(header.ParentHash)
if ptd == nil {
return NonStatTy, ParentError(header.ParentHash)
}
localTd := hc.GetTd(hc.currentHeaderHash)
externTd := new(big.Int).Add(header.Difficulty, ptd)
// If the total difficulty is higher than our known, add it to the canonical chain
// Second clause in the if statement reduces the vulnerability to selfish mining.
// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) {
// Delete any canonical number assignments above the new head
for i := number + 1; GetCanonicalHash(hc.chainDb, i) != (common.Hash{}); i++ {
DeleteCanonicalHash(hc.chainDb, i)
}
// Overwrite any stale canonical number assignments
var (
headHash = header.ParentHash
headHeader = hc.GetHeader(headHash)
headNumber = headHeader.Number.Uint64()
)
for GetCanonicalHash(hc.chainDb, headNumber) != headHash {
WriteCanonicalHash(hc.chainDb, headHash, headNumber)
headHash = headHeader.ParentHash
headHeader = hc.GetHeader(headHash)
headNumber = headHeader.Number.Uint64()
}
// Extend the canonical chain with the new header
if err := WriteCanonicalHash(hc.chainDb, hash, number); err != nil {
glog.Fatalf("failed to insert header number: %v", err)
}
if err := WriteHeadHeaderHash(hc.chainDb, hash); err != nil {
glog.Fatalf("failed to insert head header hash: %v", err)
}
hc.currentHeaderHash, hc.currentHeader = hash, types.CopyHeader(header)
status = CanonStatTy
} else {
status = SideStatTy
}
// Irrelevant of the canonical status, write the header itself to the database
if err := hc.WriteTd(hash, externTd); err != nil {
glog.Fatalf("failed to write header total difficulty: %v", err)
}
if err := WriteHeader(hc.chainDb, header); err != nil {
glog.Fatalf("failed to write header contents: %v", err)
}
hc.headerCache.Add(hash, header)
return
}
// ValidateHeader validates the given header and, depending on the pow arg,
// checks the proof of work of the given header. Returns an error if the
// validation failed.
func (v *BlockValidator) ValidateHeader(header, parent *types.Header, checkPow bool) error {
// Short circuit if the parent is missing.
if parent == nil {
return ParentError(header.ParentHash)
}
// Short circuit if the header's already known or its parent missing
if v.bc.HasHeader(header.Hash()) {
return nil
}
return ValidateHeader(v.config, v.Pow, header, parent, checkPow, false)
}
// ValidateHeader verifies the validity of a header, relying on the database and
// POW behind the block processor.
func (sm *BlockProcessor) ValidateHeader(header *types.Header, checkPow, uncle bool) error {
// Short circuit if the header's already known or its parent missing
if sm.bc.HasHeader(header.Hash()) {
return nil
}
if parent := sm.bc.GetHeader(header.ParentHash); parent == nil {
return ParentError(header.ParentHash)
} else {
return ValidateHeader(sm.Pow, header, parent, checkPow, uncle)
}
}
// WriteHeader serializes a block header into the database.
func WriteHeader(db ethdb.Database, header *types.Header) error {
data, err := rlp.EncodeToBytes(header)
if err != nil {
return err
}
key := append(append(blockPrefix, header.Hash().Bytes()...), headerSuffix...)
if err := db.Put(key, data); err != nil {
glog.Fatalf("failed to store header into database: %v", err)
return err
}
glog.V(logger.Debug).Infof("stored header #%v [%x…]", header.Number, header.Hash().Bytes()[:4])
return nil
}
func (self *worker) commitUncle(work *Work, uncle *types.Header) error {
hash := uncle.Hash()
if work.uncles.Has(hash) {
return core.UncleError("Uncle not unique")
}
if !work.ancestors.Has(uncle.ParentHash) {
return core.UncleError(fmt.Sprintf("Uncle's parent unknown (%x)", uncle.ParentHash[0:4]))
}
if work.family.Has(hash) {
return core.UncleError(fmt.Sprintf("Uncle already in family (%x)", hash))
}
work.uncles.Add(uncle.Hash())
return nil
}
// Validates a header. Returns an error if the header is invalid.
//
// See YP section 4.3.4. "Block Header Validity"
func ValidateHeader(config *ChainConfig, pow pow.PoW, header *types.Header, parent *types.Header, checkPow, uncle bool) error {
if big.NewInt(int64(len(header.Extra))).Cmp(params.MaximumExtraDataSize) == 1 {
return fmt.Errorf("Header extra data too long (%d)", len(header.Extra))
}
if uncle {
if header.Time.Cmp(common.MaxBig) == 1 {
return BlockTSTooBigErr
}
} else {
if header.Time.Cmp(big.NewInt(time.Now().Unix())) == 1 {
return BlockFutureErr
}
}
if header.Time.Cmp(parent.Time) != 1 {
return BlockEqualTSErr
}
expd := CalcDifficulty(config, header.Time.Uint64(), parent.Time.Uint64(), parent.Number, parent.Difficulty)
if expd.Cmp(header.Difficulty) != 0 {
return fmt.Errorf("Difficulty check failed for header %v, %v", header.Difficulty, expd)
}
a := new(big.Int).Set(parent.GasLimit)
a = a.Sub(a, header.GasLimit)
a.Abs(a)
b := new(big.Int).Set(parent.GasLimit)
b = b.Div(b, params.GasLimitBoundDivisor)
if !(a.Cmp(b) < 0) || (header.GasLimit.Cmp(params.MinGasLimit) == -1) {
return fmt.Errorf("GasLimit check failed for header %v (%v > %v)", header.GasLimit, a, b)
}
num := new(big.Int).Set(parent.Number)
num.Sub(header.Number, num)
if num.Cmp(big.NewInt(1)) != 0 {
return BlockNumberErr
}
if checkPow {
// Verify the nonce of the header. Return an error if it's not valid
if !pow.Verify(types.NewBlockWithHeader(header)) {
return &BlockNonceErr{header.Number, header.Hash(), header.Nonce.Uint64()}
}
}
// If all checks passed, validate the extra-data field for hard forks
return ValidateDAOHeaderExtraData(config, header)
}
func (self *worker) commitUncle(uncle *types.Header) error {
if self.current.uncles.Has(uncle.Hash()) {
// Error not unique
return core.UncleError("Uncle not unique")
}
self.current.uncles.Add(uncle.Hash())
if !self.current.family.Has(uncle.ParentHash) {
return core.UncleError(fmt.Sprintf("Uncle's parent unknown (%x)", uncle.ParentHash[0:4]))
}
if self.current.family.Has(uncle.Hash()) {
return core.UncleError(fmt.Sprintf("Uncle already in family (%x)", uncle.Hash()))
}
return nil
}
func NewUncleRes(h *types.Header) *UncleRes {
if h == nil {
return nil
}
var v = new(UncleRes)
v.BlockNumber = newHexNum(h.Number)
v.BlockHash = newHexData(h.Hash())
v.ParentHash = newHexData(h.ParentHash)
v.Sha3Uncles = newHexData(h.UncleHash)
v.Nonce = newHexData(h.Nonce[:])
v.LogsBloom = newHexData(h.Bloom)
v.TransactionRoot = newHexData(h.TxHash)
v.StateRoot = newHexData(h.Root)
v.Miner = newHexData(h.Coinbase)
v.Difficulty = newHexNum(h.Difficulty)
v.ExtraData = newHexData(h.Extra)
v.GasLimit = newHexNum(h.GasLimit)
v.GasUsed = newHexNum(h.GasUsed)
v.UnixTimestamp = newHexNum(h.Time)
v.ReceiptHash = newHexData(h.ReceiptHash)
return v
}
// writeHeader writes a header into the local chain, given that its parent is
// already known. If the total difficulty of the newly inserted header becomes
// greater than the current known TD, the canonical chain is re-routed.
//
// Note: This method is not concurrent-safe with inserting blocks simultaneously
// into the chain, as side effects caused by reorganisations cannot be emulated
// without the real blocks. Hence, writing headers directly should only be done
// in two scenarios: pure-header mode of operation (light clients), or properly
// separated header/block phases (non-archive clients).
func (self *BlockChain) writeHeader(header *types.Header) error {
self.wg.Add(1)
defer self.wg.Done()
// Calculate the total difficulty of the header
ptd := self.GetTd(header.ParentHash)
if ptd == nil {
return ParentError(header.ParentHash)
}
localTd := self.GetTd(self.currentHeader.Hash())
externTd := new(big.Int).Add(header.Difficulty, ptd)
// Make sure no inconsistent state is leaked during insertion
self.mu.Lock()
defer self.mu.Unlock()
// If the total difficulty is higher than our known, add it to the canonical chain
// Second clause in the if statement reduces the vulnerability to selfish mining.
// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) {
// Delete any canonical number assignments above the new head
for i := header.Number.Uint64() + 1; GetCanonicalHash(self.chainDb, i) != (common.Hash{}); i++ {
DeleteCanonicalHash(self.chainDb, i)
}
// Overwrite any stale canonical number assignments
head := self.GetHeader(header.ParentHash)
for GetCanonicalHash(self.chainDb, head.Number.Uint64()) != head.Hash() {
WriteCanonicalHash(self.chainDb, head.Hash(), head.Number.Uint64())
head = self.GetHeader(head.ParentHash)
}
// Extend the canonical chain with the new header
if err := WriteCanonicalHash(self.chainDb, header.Hash(), header.Number.Uint64()); err != nil {
glog.Fatalf("failed to insert header number: %v", err)
}
if err := WriteHeadHeaderHash(self.chainDb, header.Hash()); err != nil {
glog.Fatalf("failed to insert head header hash: %v", err)
}
self.currentHeader = types.CopyHeader(header)
}
// Irrelevant of the canonical status, write the header itself to the database
if err := WriteTd(self.chainDb, header.Hash(), externTd); err != nil {
glog.Fatalf("failed to write header total difficulty: %v", err)
}
if err := WriteHeader(self.chainDb, header); err != nil {
glog.Fatalf("filed to write header contents: %v", err)
}
return nil
}
// writeHeader writes a header into the local chain, given that its parent is
// already known. If the total difficulty of the newly inserted header becomes
// greater than the current known TD, the canonical chain is re-routed.
//
// Note: This method is not concurrent-safe with inserting blocks simultaneously
// into the chain, as side effects caused by reorganisations cannot be emulated
// without the real blocks. Hence, writing headers directly should only be done
// in two scenarios: pure-header mode of operation (light clients), or properly
// separated header/block phases (non-archive clients).
func (self *BlockChain) writeHeader(header *types.Header) error {
self.wg.Add(1)
defer self.wg.Done()
// Calculate the total difficulty of the header
ptd := self.GetTd(header.ParentHash)
if ptd == nil {
return ParentError(header.ParentHash)
}
td := new(big.Int).Add(header.Difficulty, ptd)
// Make sure no inconsistent state is leaked during insertion
self.mu.Lock()
defer self.mu.Unlock()
// If the total difficulty is higher than our known, add it to the canonical chain
if td.Cmp(self.GetTd(self.currentHeader.Hash())) > 0 {
// Delete any canonical number assignments above the new head
for i := header.Number.Uint64() + 1; GetCanonicalHash(self.chainDb, i) != (common.Hash{}); i++ {
DeleteCanonicalHash(self.chainDb, i)
}
// Overwrite any stale canonical number assignments
head := self.GetHeader(header.ParentHash)
for GetCanonicalHash(self.chainDb, head.Number.Uint64()) != head.Hash() {
WriteCanonicalHash(self.chainDb, head.Hash(), head.Number.Uint64())
head = self.GetHeader(head.ParentHash)
}
// Extend the canonical chain with the new header
if err := WriteCanonicalHash(self.chainDb, header.Hash(), header.Number.Uint64()); err != nil {
glog.Fatalf("failed to insert header number: %v", err)
}
if err := WriteHeadHeaderHash(self.chainDb, header.Hash()); err != nil {
glog.Fatalf("failed to insert head header hash: %v", err)
}
self.currentHeader = types.CopyHeader(header)
}
// Irrelevant of the canonical status, write the header itself to the database
if err := WriteTd(self.chainDb, header.Hash(), td); err != nil {
glog.Fatalf("failed to write header total difficulty: %v", err)
}
if err := WriteHeader(self.chainDb, header); err != nil {
glog.Fatalf("filed to write header contents: %v", err)
}
return nil
}
// ValidateHeaderWithParent verifies the validity of a header, relying on the database and
// POW behind the block processor.
func (sm *BlockProcessor) ValidateHeaderWithParent(header, parent *types.Header, checkPow, uncle bool) error {
if sm.bc.HasHeader(header.Hash()) {
return nil
}
return ValidateHeader(sm.Pow, header, parent, checkPow, uncle)
}