Function VerifyScript

bitcoin/core/scripteval.py:737–787

Verify a scriptSig satisfies a scriptPubKey scriptSig - Signature scriptPubKey - PubKey txTo - Spending transaction inIdx - Index of the transaction input containing scriptSig Raises a ValidationError subclass if the validation fails.

(scriptSig, scriptPubKey, txTo, inIdx, flags=())

    pass

def VerifyScript(scriptSig, scriptPubKey, txTo, inIdx, flags=()):
    """Verify a scriptSig satisfies a scriptPubKey

    scriptSig    - Signature

    scriptPubKey - PubKey

    txTo         - Spending transaction

    inIdx        - Index of the transaction input containing scriptSig

    Raises a ValidationError subclass if the validation fails.
    """
    stack = []
    EvalScript(stack, scriptSig, txTo, inIdx, flags=flags)
    if SCRIPT_VERIFY_P2SH in flags:
        stackCopy = list(stack)
    EvalScript(stack, scriptPubKey, txTo, inIdx, flags=flags)
    if len(stack) == 0:
        raise VerifyScriptError("scriptPubKey left an empty stack")
    if not _CastToBool(stack[-1]):
        raise VerifyScriptError("scriptPubKey returned false")

    # Additional validation for spend-to-script-hash transactions
    if SCRIPT_VERIFY_P2SH in flags and scriptPubKey.is_p2sh():
        if not scriptSig.is_push_only():
            raise VerifyScriptError("P2SH scriptSig not is_push_only()")

        # restore stack
        stack = stackCopy

        # stack cannot be empty here, because if it was the
        # P2SH  HASH <> EQUAL  scriptPubKey would be evaluated with
        # an empty stack and the EvalScript above would return false.
        assert len(stack)

        pubKey2 = CScript(stack.pop())

        EvalScript(stack, pubKey2, txTo, inIdx, flags=flags)

        if not len(stack):
            raise VerifyScriptError("P2SH inner scriptPubKey left an empty stack")

        if not _CastToBool(stack[-1]):
            raise VerifyScriptError("P2SH inner scriptPubKey returned false")

    if SCRIPT_VERIFY_CLEANSTACK in flags:
        assert SCRIPT_VERIFY_P2SH in flags

        if len(stack) != 1:
            raise VerifyScriptError("scriptPubKey left extra items on stack")


class VerifySignatureError(bitcoin.core.ValidationError):