p2p: Add witness mutation check inside FillBlock

Since #29412, we have not allowed mutated blocks to continue
being processed immediately the block is received, but this
is only done for the legacy BLOCK message.

Extend these checks as belt-and-suspenders to not allow
similar mutation strategies to affect relay by honest peers
by applying the check inside
PartiallyDownloadedBlock::FillBlock, immediately before
returning READ_STATUS_OK.

This also removes the extraneous CheckBlock call.

Github-Pull: #32646
Rebased-From: bac9ee4830
This commit is contained in:
Greg Sanders
2025-05-21 13:36:43 -04:00
committed by fanquake
parent e97588fc3d
commit 9b95ab5e9d
5 changed files with 37 additions and 52 deletions

View File

@@ -32,14 +32,10 @@ void initialize_pdb()
g_setup = testing_setup.get();
}
PartiallyDownloadedBlock::CheckBlockFn FuzzedCheckBlock(std::optional<BlockValidationResult> result)
PartiallyDownloadedBlock::IsBlockMutatedFn FuzzedIsBlockMutated(bool result)
{
return [result](const CBlock&, BlockValidationState& state, const Consensus::Params&, bool, bool) {
if (result) {
return state.Invalid(*result);
}
return true;
return [result](const CBlock& block, bool) {
return result;
};
}
@@ -111,36 +107,23 @@ FUZZ_TARGET(partially_downloaded_block, .init = initialize_pdb)
skipped_missing |= (!pdb.IsTxAvailable(i) && skip);
}
// Mock CheckBlock
bool fail_check_block{fuzzed_data_provider.ConsumeBool()};
auto validation_result =
fuzzed_data_provider.PickValueInArray(
{BlockValidationResult::BLOCK_RESULT_UNSET,
BlockValidationResult::BLOCK_CONSENSUS,
BlockValidationResult::BLOCK_CACHED_INVALID,
BlockValidationResult::BLOCK_INVALID_HEADER,
BlockValidationResult::BLOCK_MUTATED,
BlockValidationResult::BLOCK_MISSING_PREV,
BlockValidationResult::BLOCK_INVALID_PREV,
BlockValidationResult::BLOCK_TIME_FUTURE,
BlockValidationResult::BLOCK_CHECKPOINT,
BlockValidationResult::BLOCK_HEADER_LOW_WORK});
pdb.m_check_block_mock = FuzzedCheckBlock(
fail_check_block ?
std::optional<BlockValidationResult>{validation_result} :
std::nullopt);
bool segwit_active{fuzzed_data_provider.ConsumeBool()};
// Mock IsBlockMutated
bool fail_block_mutated{fuzzed_data_provider.ConsumeBool()};
pdb.m_check_block_mutated_mock = FuzzedIsBlockMutated(fail_block_mutated);
CBlock reconstructed_block;
auto fill_status{pdb.FillBlock(reconstructed_block, missing)};
auto fill_status{pdb.FillBlock(reconstructed_block, missing, segwit_active)};
switch (fill_status) {
case READ_STATUS_OK:
assert(!skipped_missing);
assert(!fail_check_block);
assert(!fail_block_mutated);
assert(block->GetHash() == reconstructed_block.GetHash());
break;
case READ_STATUS_CHECKBLOCK_FAILED: [[fallthrough]];
case READ_STATUS_FAILED:
assert(fail_check_block);
assert(fail_block_mutated);
break;
case READ_STATUS_INVALID:
break;