Function CheckBlock

src/validation.cpp:3570–3642

}

bool CheckBlock(const CBlock& block, BlockValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW, bool fCheckMerkleRoot)
{
    // These are checks that are independent of context.

    if (block.fChecked)
        return true;

    // Check that the header is valid (particularly PoW).  This is mostly
    // redundant with the call in AcceptBlockHeader.
    if (!CheckBlockHeader(block, state, consensusParams, fCheckPOW))
        return false;

    // Signet only: check block solution
    if (consensusParams.signet_blocks && fCheckPOW && !CheckSignetBlockSolution(block, consensusParams)) {
        return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-signet-blksig", "signet block signature validation failure");
    }

    // Check the merkle root.
    if (fCheckMerkleRoot) {
        bool mutated;
        uint256 hashMerkleRoot2 = BlockMerkleRoot(block, &mutated);
        if (block.hashMerkleRoot != hashMerkleRoot2)
            return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-txnmrklroot", "hashMerkleRoot mismatch");

        // Check for merkle tree malleability (CVE-2012-2459): repeating sequences
        // of transactions in a block without affecting the merkle root of a block,
        // while still invalidating it.
        if (mutated)
            return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-txns-duplicate", "duplicate transaction");
    }

    // All potential-corruption validation must be done before we do any
    // transaction validation, as otherwise we may mark the header as invalid
    // because we receive the wrong transactions for it.
    // Note that witness malleability is checked in ContextualCheckBlock, so no
    // checks that use witness data may be performed here.

    // Size limits
    if (block.vtx.empty() || block.vtx.size() * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT || ::GetSerializeSize(block, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
        return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-blk-length", "size limits failed");

    // First transaction must be coinbase, the rest must not be
    if (block.vtx.empty() || !block.vtx[0]->IsCoinBase())
        return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-missing", "first tx is not coinbase");
    for (unsigned int i = 1; i < block.vtx.size(); i++)
        if (block.vtx[i]->IsCoinBase())
            return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-multiple", "more than one coinbase");

    // Check transactions
    // Must check for duplicate inputs (see CVE-2018-17144)
    for (const auto& tx : block.vtx) {
        TxValidationState tx_state;
        if (!CheckTransaction(*tx, tx_state)) {
            // CheckBlock() does context-free validation checks. The only
            // possible failures are consensus failures.
            assert(tx_state.GetResult() == TxValidationResult::TX_CONSENSUS);
            return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, tx_state.GetRejectReason(),
                                 strprintf("Transaction check failed (tx hash %s) %s", tx->GetHash().ToString(), tx_state.GetDebugMessage()));