Function IsLowDERSignature

src/script/interpreter.cpp:254–269

}

bool static IsLowDERSignature(const valtype &vchSig, ScriptError* serror) {
    if (!IsValidSignatureEncoding(vchSig)) {
        return set_error(serror, SCRIPT_ERR_SIG_DER);
    }
    // https://bitcoin.stackexchange.com/a/12556:
    //     Also note that inside transaction signatures, an extra hashtype byte
    //     follows the actual signature data.
    std::vector<unsigned char> vchSigCopy(vchSig.begin(), vchSig.begin() + vchSig.size() - 1);
    // If the S value is above the order of the curve divided by two, its
    // complement modulo the order could have been used instead, which is
    // one byte shorter when encoded correctly.
    if (!CPubKey::CheckLowS(vchSigCopy)) {
        return set_error(serror, SCRIPT_ERR_SIG_HIGH_S);
    }
    return true;
}

bool static IsDefinedHashtypeSignature(const valtype &vchSig, unsigned int flags) {
    if (vchSig.size() == 0) {