From 6b4f231f5f0f88690488c4da20ea1c180dbc4b19 Mon Sep 17 00:00:00 2001 From: Andrew Chow Date: Fri, 9 Jun 2017 22:38:06 -0700 Subject: Move transaction combining from signrawtransaction to new RPC Create a combinerawtransaction RPC which accepts a json array of hex raw transactions to combine them into one transaction. Signrawtransaction is changed to no longer combine transactions and only accept one transaction at a time. --- src/rpc/client.cpp | 1 + src/rpc/rawtransaction.cpp | 135 +++++++++++++++++++++++++++++++++------------ 2 files changed, 101 insertions(+), 35 deletions(-) (limited to 'src') diff --git a/src/rpc/client.cpp b/src/rpc/client.cpp index 775ad4b6c9..d82e85f825 100644 --- a/src/rpc/client.cpp +++ b/src/rpc/client.cpp @@ -95,6 +95,7 @@ static const CRPCConvertParam vRPCConvertParams[] = { "signrawtransaction", 1, "prevtxs" }, { "signrawtransaction", 2, "privkeys" }, { "sendrawtransaction", 1, "allowhighfees" }, + { "combinerawtransaction", 0, "txs" }, { "fundrawtransaction", 1, "options" }, { "gettxout", 1, "n" }, { "gettxout", 2, "include_mempool" }, diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index b878624df8..10886fea9f 100644 --- a/src/rpc/rawtransaction.cpp +++ b/src/rpc/rawtransaction.cpp @@ -554,6 +554,93 @@ static void TxInErrorToJSON(const CTxIn& txin, UniValue& vErrorsRet, const std:: vErrorsRet.push_back(entry); } +UniValue combinerawtransaction(const JSONRPCRequest& request) +{ + + if (request.fHelp || request.params.size() != 1) + throw std::runtime_error( + "combinerawtransaction [\"hexstring\",...]\n" + "\nCombine multiple partially signed transactions into one transaction.\n" + "The combined transaction may be another partially signed transaction or a \n" + "fully signed transaction." + + "\nArguments:\n" + "1. \"txs\" (string) A json array of hex strings of partially signed transactions\n" + " [\n" + " \"hexstring\" (string) A transaction hash\n" + " ,...\n" + " ]\n" + + "\nResult:\n" + "\"hex\" : \"value\", (string) The hex-encoded raw transaction with signature(s)\n" + + "\nExamples:\n" + + HelpExampleCli("combinerawtransaction", "[\"myhex1\", \"myhex2\", \"myhex3\"]") + ); + + + UniValue txs = request.params[0].get_array(); + std::vector txVariants(txs.size()); + + for (unsigned int idx = 0; idx < txs.size(); idx++) { + if (!DecodeHexTx(txVariants[idx], txs[idx].get_str(), true)) { + throw JSONRPCError(RPC_DESERIALIZATION_ERROR, strprintf("TX decode failed for tx %d", idx)); + } + } + + if (txVariants.empty()) { + throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Missing transactions"); + } + + // mergedTx will end up with all the signatures; it + // starts as a clone of the rawtx: + CMutableTransaction mergedTx(txVariants[0]); + + // Fetch previous transactions (inputs): + CCoinsView viewDummy; + CCoinsViewCache view(&viewDummy); + { + LOCK(cs_main); + LOCK(mempool.cs); + CCoinsViewCache &viewChain = *pcoinsTip; + CCoinsViewMemPool viewMempool(&viewChain, mempool); + view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view + + for (const CTxIn& txin : mergedTx.vin) { + view.AccessCoin(txin.prevout); // Load entries from viewChain into view; can fail. + } + + view.SetBackend(viewDummy); // switch back to avoid locking mempool for too long + } + + // Use CTransaction for the constant parts of the + // transaction to avoid rehashing. + const CTransaction txConst(mergedTx); + // Sign what we can: + for (unsigned int i = 0; i < mergedTx.vin.size(); i++) { + CTxIn& txin = mergedTx.vin[i]; + const Coin& coin = view.AccessCoin(txin.prevout); + if (coin.IsSpent()) { + throw JSONRPCError(RPC_VERIFY_ERROR, "Input not found or already spent"); + } + const CScript& prevPubKey = coin.out.scriptPubKey; + const CAmount& amount = coin.out.nValue; + + SignatureData sigdata; + + // ... and merge in other signatures: + for (const CMutableTransaction& txv : txVariants) { + if (txv.vin.size() > i) { + sigdata = CombineSignatures(prevPubKey, TransactionSignatureChecker(&txConst, i, amount), sigdata, DataFromTransaction(txv, i)); + } + } + + UpdateTransaction(mergedTx, i, sigdata); + } + + return EncodeHexTx(mergedTx); +} + UniValue signrawtransaction(const JSONRPCRequest& request) { #ifdef ENABLE_WALLET @@ -626,26 +713,9 @@ UniValue signrawtransaction(const JSONRPCRequest& request) #endif RPCTypeCheck(request.params, {UniValue::VSTR, UniValue::VARR, UniValue::VARR, UniValue::VSTR}, true); - std::vector txData(ParseHexV(request.params[0], "argument 1")); - CDataStream ssData(txData, SER_NETWORK, PROTOCOL_VERSION); - std::vector txVariants; - while (!ssData.empty()) { - try { - CMutableTransaction tx; - ssData >> tx; - txVariants.push_back(tx); - } - catch (const std::exception&) { - throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "TX decode failed"); - } - } - - if (txVariants.empty()) - throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Missing transaction"); - - // mergedTx will end up with all the signatures; it - // starts as a clone of the rawtx: - CMutableTransaction mergedTx(txVariants[0]); + CMutableTransaction mtx; + if (!DecodeHexTx(mtx, request.params[0].get_str(), true)) + throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "TX decode failed"); // Fetch previous transactions (inputs): CCoinsView viewDummy; @@ -656,7 +726,7 @@ UniValue signrawtransaction(const JSONRPCRequest& request) CCoinsViewMemPool viewMempool(&viewChain, mempool); view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view - for (const CTxIn& txin : mergedTx.vin) { + for (const CTxIn& txin : mtx.vin) { view.AccessCoin(txin.prevout); // Load entries from viewChain into view; can fail. } @@ -781,10 +851,10 @@ UniValue signrawtransaction(const JSONRPCRequest& request) // Use CTransaction for the constant parts of the // transaction to avoid rehashing. - const CTransaction txConst(mergedTx); + const CTransaction txConst(mtx); // Sign what we can: - for (unsigned int i = 0; i < mergedTx.vin.size(); i++) { - CTxIn& txin = mergedTx.vin[i]; + for (unsigned int i = 0; i < mtx.vin.size(); i++) { + CTxIn& txin = mtx.vin[i]; const Coin& coin = view.AccessCoin(txin.prevout); if (coin.IsSpent()) { TxInErrorToJSON(txin, vErrors, "Input not found or already spent"); @@ -795,17 +865,11 @@ UniValue signrawtransaction(const JSONRPCRequest& request) SignatureData sigdata; // Only sign SIGHASH_SINGLE if there's a corresponding output: - if (!fHashSingle || (i < mergedTx.vout.size())) - ProduceSignature(MutableTransactionSignatureCreator(&keystore, &mergedTx, i, amount, nHashType), prevPubKey, sigdata); + if (!fHashSingle || (i < mtx.vout.size())) + ProduceSignature(MutableTransactionSignatureCreator(&keystore, &mtx, i, amount, nHashType), prevPubKey, sigdata); + sigdata = CombineSignatures(prevPubKey, TransactionSignatureChecker(&txConst, i, amount), sigdata, DataFromTransaction(mtx, i)); - // ... and merge in other signatures: - for (const CMutableTransaction& txv : txVariants) { - if (txv.vin.size() > i) { - sigdata = CombineSignatures(prevPubKey, TransactionSignatureChecker(&txConst, i, amount), sigdata, DataFromTransaction(txv, i)); - } - } - - UpdateTransaction(mergedTx, i, sigdata); + UpdateTransaction(mtx, i, sigdata); ScriptError serror = SCRIPT_ERR_OK; if (!VerifyScript(txin.scriptSig, prevPubKey, &txin.scriptWitness, STANDARD_SCRIPT_VERIFY_FLAGS, TransactionSignatureChecker(&txConst, i, amount), &serror)) { @@ -815,7 +879,7 @@ UniValue signrawtransaction(const JSONRPCRequest& request) bool fComplete = vErrors.empty(); UniValue result(UniValue::VOBJ); - result.push_back(Pair("hex", EncodeHexTx(mergedTx))); + result.push_back(Pair("hex", EncodeHexTx(mtx))); result.push_back(Pair("complete", fComplete)); if (!vErrors.empty()) { result.push_back(Pair("errors", vErrors)); @@ -905,6 +969,7 @@ static const CRPCCommand commands[] = { "rawtransactions", "decoderawtransaction", &decoderawtransaction, true, {"hexstring"} }, { "rawtransactions", "decodescript", &decodescript, true, {"hexstring"} }, { "rawtransactions", "sendrawtransaction", &sendrawtransaction, false, {"hexstring","allowhighfees"} }, + { "rawtransactions", "combinerawtransaction", &combinerawtransaction, true, {"txs"} }, { "rawtransactions", "signrawtransaction", &signrawtransaction, false, {"hexstring","prevtxs","privkeys","sighashtype"} }, /* uses wallet if enabled */ { "blockchain", "gettxoutproof", &gettxoutproof, true, {"txids", "blockhash"} }, -- cgit v1.2.3