Function VerifyScript

src/script/interpreter.cpp:2304–2451

}

std::optional<ScriptError> VerifyScript(
    const verify_script_params& params,
    const task::CCancellationToken& token,
    const CScript& scriptSig,
    const CScript& scriptPubKey,
    uint32_t flags,       
    const BaseSignatureChecker& checker)
{
    if(!valid_flags(flags))
        return SCRIPT_ERR_INVALID_FLAGS;

    if (flags & SCRIPT_ENABLE_SIGHASH_FORKID)
    {
        // If FORKID is enabled, we also ensure strict encoding.
        flags |= SCRIPT_VERIFY_STRICTENC;
    }

    if(VerifySigPushOnly(flags))
    {
        // Check for push-only scriptSig if:
        // - we are post-Genesis but pre-Chronicle, or
        // - we are post-Chronicle and the txn is non-malleable
        if((IsGenesis(flags) && !IsChronicle(flags)) ||
           (IsChronicle(flags) && !IsMalleableTxnVersion(checker.Version())))
        {
            if(!scriptSig.IsPushOnly())
            {
                return SCRIPT_ERR_SIG_PUSHONLY;
            }
        }
    }

    LimitedStack stack{params.MaxStackMemoryUsage()};
    LimitedStack stackCopy{params.MaxStackMemoryUsage()};
    if(const auto o = EvalScript(params.EvalScriptParams(),
                                 token,
                                 stack,
                                 scriptSig,
                                 &scriptPubKey,
                                 flags,
                                 checker);
       !o.has_value())
    {
        return {};
    }
    else if(o.value() != SCRIPT_ERR_OK)
    {
        return o;
    }

    if ((flags & SCRIPT_VERIFY_P2SH)  && !(flags & SCRIPT_UTXO_AFTER_GENESIS)) {
        stackCopy = stack.makeRootStackCopy();
    }

    if(const auto o = EvalScript(params.EvalScriptParams(),
                                 token,
                                 stack,
                                 scriptPubKey,