diff options
| author | fanquake <fanquake@gmail.com> | 2020-04-26 20:01:46 +0800 |
|---|---|---|
| committer | fanquake <fanquake@gmail.com> | 2020-04-29 11:20:22 +0800 |
| commit | 06442549f8b725f46c1c727e9eb6fde6b843503c (patch) | |
| tree | 13cccca00de2f9c22549cb878df0b5923fbfb8af | |
| parent | ba348dbc518b8e082a5dc3a225432fdacf859a13 (diff) | |
validation: Add minimum witness commitment size constant
Per BIP 141, the witness commitment structure is atleast 38 bytes,
OP_RETURN (0x6a) + 36 (0x24) + 4 byte header (0xaa21a9ed) + 32 byte
SHA256 hash. It can be longer, however any additional data has no
consensus meaning.
| -rw-r--r-- | src/validation.cpp | 11 | ||||
| -rw-r--r-- | src/validation.h | 2 |
2 files changed, 11 insertions, 2 deletions
diff --git a/src/validation.cpp b/src/validation.cpp index 25975e3e31..8f873bb3a6 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -3386,7 +3386,14 @@ int GetWitnessCommitmentIndex(const CBlock& block) int commitpos = -1; if (!block.vtx.empty()) { for (size_t o = 0; o < block.vtx[0]->vout.size(); o++) { - if (block.vtx[0]->vout[o].scriptPubKey.size() >= 38 && block.vtx[0]->vout[o].scriptPubKey[0] == OP_RETURN && block.vtx[0]->vout[o].scriptPubKey[1] == 0x24 && block.vtx[0]->vout[o].scriptPubKey[2] == 0xaa && block.vtx[0]->vout[o].scriptPubKey[3] == 0x21 && block.vtx[0]->vout[o].scriptPubKey[4] == 0xa9 && block.vtx[0]->vout[o].scriptPubKey[5] == 0xed) { + const CTxOut& vout = block.vtx[0]->vout[o]; + if (vout.scriptPubKey.size() >= MINIMUM_WITNESS_COMMITMENT && + vout.scriptPubKey[0] == OP_RETURN && + vout.scriptPubKey[1] == 0x24 && + vout.scriptPubKey[2] == 0xaa && + vout.scriptPubKey[3] == 0x21 && + vout.scriptPubKey[4] == 0xa9 && + vout.scriptPubKey[5] == 0xed) { commitpos = o; } } @@ -3417,7 +3424,7 @@ std::vector<unsigned char> GenerateCoinbaseCommitment(CBlock& block, const CBloc CHash256().Write(witnessroot.begin(), 32).Write(ret.data(), 32).Finalize(witnessroot.begin()); CTxOut out; out.nValue = 0; - out.scriptPubKey.resize(38); + out.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT); out.scriptPubKey[0] = OP_RETURN; out.scriptPubKey[1] = 0x24; out.scriptPubKey[2] = 0xaa; diff --git a/src/validation.h b/src/validation.h index 91b1ba6497..0169362768 100644 --- a/src/validation.h +++ b/src/validation.h @@ -92,6 +92,8 @@ static const unsigned int DEFAULT_CHECKLEVEL = 3; // one 128MB block file + added 15% undo data = 147MB greater for a total of 545MB // Setting the target to >= 550 MiB will make it likely we can respect the target. static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024; +/** Minimum size of a witness commitment structure. Defined in BIP 141. **/ +static constexpr size_t MINIMUM_WITNESS_COMMITMENT{38}; struct BlockHasher { |