Function MutateTxAddOutMultiSig

src/bitcoin-tx.cpp:362–433

}

static void MutateTxAddOutMultiSig(CMutableTransaction& tx, const std::string& strInput)
{
    // Separate into VALUE:REQUIRED:NUMKEYS:PUBKEY1:PUBKEY2:....[:FLAGS]
    std::vector<std::string> vStrInputParts = SplitString(strInput, ':');

    // Check that there are enough parameters
    if (vStrInputParts.size()<3)
        throw std::runtime_error("Not enough multisig parameters");

    // Extract and validate VALUE
    CAmount value = ExtractAndValidateValue(vStrInputParts[0]);

    // Extract REQUIRED
    const uint32_t required{TrimAndParse<uint32_t>(vStrInputParts.at(1), "invalid multisig required number")};

    // Extract NUMKEYS
    const uint32_t numkeys{TrimAndParse<uint32_t>(vStrInputParts.at(2), "invalid multisig total number")};

    // Validate there are the correct number of pubkeys
    if (vStrInputParts.size() < numkeys + 3)
        throw std::runtime_error("incorrect number of multisig pubkeys");

    if (required < 1 || required > MAX_PUBKEYS_PER_MULTISIG || numkeys < 1 || numkeys > MAX_PUBKEYS_PER_MULTISIG || numkeys < required)
        throw std::runtime_error("multisig parameter mismatch. Required " \
                            + ToString(required) + " of " + ToString(numkeys) + "signatures.");

    // extract and validate PUBKEYs
    std::vector<CPubKey> pubkeys;
    for(int pos = 1; pos <= int(numkeys); pos++) {
        CPubKey pubkey(ParseHex(vStrInputParts[pos + 2]));
        if (!pubkey.IsFullyValid())
            throw std::runtime_error("invalid TX output pubkey");
        pubkeys.push_back(pubkey);
    }

    // Extract FLAGS
    bool bSegWit = false;
    bool bScriptHash = false;
    if (vStrInputParts.size() == numkeys + 4) {
        const std::string& flags = vStrInputParts.back();
        bSegWit = (flags.find('W') != std::string::npos);
        bScriptHash = (flags.find('S') != std::string::npos);
    }
    else if (vStrInputParts.size() > numkeys + 4) {
        // Validate that there were no more parameters passed
        throw std::runtime_error("Too many parameters");
    }

    CScript scriptPubKey = GetScriptForMultisig(required, pubkeys);

    if (bSegWit) {
        for (const CPubKey& pubkey : pubkeys) {
            if (!pubkey.IsCompressed()) {
                throw std::runtime_error("Uncompressed pubkeys are not useable for SegWit outputs");
            }
        }
        // Build a P2WSH with the multisig script
        scriptPubKey = GetScriptForDestination(WitnessV0ScriptHash(scriptPubKey));