From fb2a3a70e860aa87fb7a21f6554ed9f3ce901e2d Mon Sep 17 00:00:00 2001 From: ishaanam Date: Wed, 3 Aug 2022 19:32:59 -0400 Subject: rpc: add descriptorprocesspsbt rpc This RPC can be the Updater, Signer, and optionally the Input Finalizer for a psbt, and has no interaction with the Bitcoin Core wallet. --- src/rpc/rawtransaction.cpp | 93 +++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 87 insertions(+), 6 deletions(-) (limited to 'src/rpc/rawtransaction.cpp') diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index 4a918cbd42..d5a5f3ce6f 100644 --- a/src/rpc/rawtransaction.cpp +++ b/src/rpc/rawtransaction.cpp @@ -172,8 +172,9 @@ static std::vector CreateTxDoc() }; } -// Update PSBT with information from the mempool, the UTXO set, the txindex, and the provided descriptors -PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std::any& context, const HidingSigningProvider& provider) +// Update PSBT with information from the mempool, the UTXO set, the txindex, and the provided descriptors. +// Optionally, sign the inputs that we can using information from the descriptors. +PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std::any& context, const HidingSigningProvider& provider, int sighash_type, bool finalize) { // Unserialize the transactions PartiallySignedTransaction psbtx; @@ -242,9 +243,10 @@ PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std } // Update script/keypath information using descriptor data. - // Note that SignPSBTInput does a lot more than just constructing ECDSA signatures - // we don't actually care about those here, in fact. - SignPSBTInput(provider, psbtx, /*index=*/i, &txdata, /*sighash=*/1); + // Note that SignPSBTInput does a lot more than just constructing ECDSA signatures. + // We only actually care about those if our signing provider doesn't hide private + // information, as is the case with `descriptorprocesspsbt` + SignPSBTInput(provider, psbtx, /*index=*/i, &txdata, sighash_type, /*out_sigdata=*/nullptr, finalize); } // Update script/keypath information using descriptor data. @@ -1697,7 +1699,9 @@ static RPCHelpMan utxoupdatepsbt() const PartiallySignedTransaction& psbtx = ProcessPSBT( request.params[0].get_str(), request.context, - HidingSigningProvider(&provider, /*hide_secret=*/true, /*hide_origin=*/false)); + HidingSigningProvider(&provider, /*hide_secret=*/true, /*hide_origin=*/false), + /*sighash_type=*/SIGHASH_ALL, + /*finalize=*/false); CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION); ssTx << psbtx; @@ -1916,6 +1920,82 @@ static RPCHelpMan analyzepsbt() }; } +RPCHelpMan descriptorprocesspsbt() +{ + return RPCHelpMan{"descriptorprocesspsbt", + "\nUpdate all segwit inputs in a PSBT with information from output descriptors, the UTXO set or the mempool. \n" + "Then, sign the inputs we are able to with information from the output descriptors. ", + { + {"psbt", RPCArg::Type::STR, RPCArg::Optional::NO, "The transaction base64 string"}, + {"descriptors", RPCArg::Type::ARR, RPCArg::Optional::NO, "An array of either strings or objects", { + {"", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "An output descriptor"}, + {"", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED, "An object with an output descriptor and extra information", { + {"desc", RPCArg::Type::STR, RPCArg::Optional::NO, "An output descriptor"}, + {"range", RPCArg::Type::RANGE, RPCArg::Default{1000}, "Up to what index HD chains should be explored (either end or [begin,end])"}, + }}, + }}, + {"sighashtype", RPCArg::Type::STR, RPCArg::Default{"DEFAULT for Taproot, ALL otherwise"}, "The signature hash type to sign with if not specified by the PSBT. Must be one of\n" + " \"DEFAULT\"\n" + " \"ALL\"\n" + " \"NONE\"\n" + " \"SINGLE\"\n" + " \"ALL|ANYONECANPAY\"\n" + " \"NONE|ANYONECANPAY\"\n" + " \"SINGLE|ANYONECANPAY\""}, + {"bip32derivs", RPCArg::Type::BOOL, RPCArg::Default{true}, "Include BIP 32 derivation paths for public keys if we know them"}, + {"finalize", RPCArg::Type::BOOL, RPCArg::Default{true}, "Also finalize inputs if possible"}, + }, + RPCResult{ + RPCResult::Type::OBJ, "", "", + { + {RPCResult::Type::STR, "psbt", "The base64-encoded partially signed transaction"}, + {RPCResult::Type::BOOL, "complete", "If the transaction has a complete set of signatures"}, + } + }, + RPCExamples{ + HelpExampleCli("descriptorprocesspsbt", "\"psbt\" \"[\\\"descriptor1\\\", \\\"descriptor2\\\"]\"") + + HelpExampleCli("descriptorprocesspsbt", "\"psbt\" \"[{\\\"desc\\\":\\\"mydescriptor\\\", \\\"range\\\":21}]\"") + }, + [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue +{ + // Add descriptor information to a signing provider + FlatSigningProvider provider; + + auto descs = request.params[1].get_array(); + for (size_t i = 0; i < descs.size(); ++i) { + EvalDescriptorStringOrObject(descs[i], provider, /*expand_priv=*/true); + } + + int sighash_type = ParseSighashString(request.params[2]); + bool bip32derivs = request.params[3].isNull() ? true : request.params[3].get_bool(); + bool finalize = request.params[4].isNull() ? true : request.params[4].get_bool(); + + const PartiallySignedTransaction& psbtx = ProcessPSBT( + request.params[0].get_str(), + request.context, + HidingSigningProvider(&provider, /*hide_secret=*/false, !bip32derivs), + sighash_type, + finalize); + + // Check whether or not all of the inputs are now signed + bool complete = true; + for (const auto& input : psbtx.inputs) { + complete &= PSBTInputSigned(input); + } + + CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION); + ssTx << psbtx; + + UniValue result(UniValue::VOBJ); + + result.pushKV("psbt", EncodeBase64(ssTx)); + result.pushKV("complete", complete); + + return result; +}, + }; +} + void RegisterRawTransactionRPCCommands(CRPCTable& t) { static const CRPCCommand commands[]{ @@ -1931,6 +2011,7 @@ void RegisterRawTransactionRPCCommands(CRPCTable& t) {"rawtransactions", &createpsbt}, {"rawtransactions", &converttopsbt}, {"rawtransactions", &utxoupdatepsbt}, + {"rawtransactions", &descriptorprocesspsbt}, {"rawtransactions", &joinpsbts}, {"rawtransactions", &analyzepsbt}, }; -- cgit v1.2.3