eth/downloader: don't require state for ancestor lookups

This commit is contained in:
Péter Szilágyi 2018-02-11 14:43:56 +02:00
parent 5cf75a30c1
commit 96dad6b6f6
No known key found for this signature in database
GPG Key ID: E9AE538CEDF8293D
2 changed files with 9 additions and 13 deletions

View File

@ -173,8 +173,8 @@ type LightChain interface {
type BlockChain interface {
LightChain
// HasBlockAndState verifies block and associated states' presence in the local chain.
HasBlockAndState(common.Hash, uint64) bool
// HasBlock verifies a block's presence in the local chain.
HasBlock(common.Hash, uint64) bool
// GetBlockByHash retrieves a block from the local chain.
GetBlockByHash(common.Hash) *types.Block
@ -582,7 +582,6 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
// Figure out the valid ancestor range to prevent rewrite attacks
floor, ceil := int64(-1), d.lightchain.CurrentHeader().Number.Uint64()
p.log.Debug("Looking for common ancestor", "local", ceil, "remote", height)
if d.mode == FullSync {
ceil = d.blockchain.CurrentBlock().NumberU64()
} else if d.mode == FastSync {
@ -591,6 +590,8 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
if ceil >= MaxForkAncestry {
floor = int64(ceil - MaxForkAncestry)
}
p.log.Debug("Looking for common ancestor", "local", ceil, "remote", height)
// Request the topmost blocks to short circuit binary ancestor lookup
head := ceil
if head > height {
@ -646,7 +647,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
continue
}
// Otherwise check if we already know the header or not
if (d.mode == FullSync && d.blockchain.HasBlockAndState(headers[i].Hash(), headers[i].Number.Uint64())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash(), headers[i].Number.Uint64())) {
if (d.mode == FullSync && d.blockchain.HasBlock(headers[i].Hash(), headers[i].Number.Uint64())) || (d.mode != FullSync && d.lightchain.HasHeader(headers[i].Hash(), headers[i].Number.Uint64())) {
number, hash = headers[i].Number.Uint64(), headers[i].Hash()
// If every header is known, even future ones, the peer straight out lied about its head
@ -711,7 +712,7 @@ func (d *Downloader) findAncestor(p *peerConnection, height uint64) (uint64, err
arrived = true
// Modify the search interval based on the response
if (d.mode == FullSync && !d.blockchain.HasBlockAndState(headers[0].Hash(), headers[0].Number.Uint64())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash(), headers[0].Number.Uint64())) {
if (d.mode == FullSync && !d.blockchain.HasBlock(headers[0].Hash(), headers[0].Number.Uint64())) || (d.mode != FullSync && !d.lightchain.HasHeader(headers[0].Hash(), headers[0].Number.Uint64())) {
end = check
break
}

View File

@ -221,14 +221,9 @@ func (dl *downloadTester) HasHeader(hash common.Hash, number uint64) bool {
return dl.GetHeaderByHash(hash) != nil
}
// HasBlockAndState checks if a block and associated state is present in the testers canonical chain.
func (dl *downloadTester) HasBlockAndState(hash common.Hash, number uint64) bool {
block := dl.GetBlockByHash(hash)
if block == nil {
return false
}
_, err := dl.stateDb.Get(block.Root().Bytes())
return err == nil
// HasBlock checks if a block is present in the testers canonical chain.
func (dl *downloadTester) HasBlock(hash common.Hash, number uint64) bool {
return dl.GetBlockByHash(hash) != nil
}
// GetHeader retrieves a header from the testers canonical chain.