core: ensure the canonical block is written before the canonical hash is set

This commit is contained in:
Bas van Kervel
2016-07-26 16:37:04 +02:00
parent 4c2cc32f2e
commit bb8059f6aa
5 changed files with 69 additions and 20 deletions

View File

@ -151,6 +151,14 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
localTd := hc.GetTd(hc.currentHeaderHash, hc.currentHeader.Number.Uint64())
externTd := new(big.Int).Add(header.Difficulty, ptd)
// Irrelevant of the canonical status, write the td and header to the database
if err := hc.WriteTd(hash, number, 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)
}
// 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
@ -176,6 +184,7 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
headNumber = headHeader.Number.Uint64() - 1
headHeader = hc.GetHeader(headHash, headNumber)
}
// 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)
@ -183,19 +192,14 @@ func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, er
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, number, 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)
hc.numberCache.Add(hash, number)