From fb2a3a70e860aa87fb7a21f6554ed9f3ce901e2d Mon Sep 17 00:00:00 2001 From: ishaanam Date: Wed, 3 Aug 2022 19:32:59 -0400 Subject: [PATCH 1/2] 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/client.cpp | 3 ++ src/rpc/rawtransaction.cpp | 93 +++++++++++++++++++++++++++++++++++--- src/rpc/util.cpp | 5 +- src/rpc/util.h | 2 +- src/test/fuzz/rpc.cpp | 1 + 5 files changed, 96 insertions(+), 8 deletions(-) diff --git a/src/rpc/client.cpp b/src/rpc/client.cpp index f3c19003ff9..d08e2d55d1d 100644 --- a/src/rpc/client.cpp +++ b/src/rpc/client.cpp @@ -133,6 +133,9 @@ static const CRPCConvertParam vRPCConvertParams[] = { "walletprocesspsbt", 1, "sign" }, { "walletprocesspsbt", 3, "bip32derivs" }, { "walletprocesspsbt", 4, "finalize" }, + { "descriptorprocesspsbt", 1, "descriptors"}, + { "descriptorprocesspsbt", 3, "bip32derivs" }, + { "descriptorprocesspsbt", 4, "finalize" }, { "createpsbt", 0, "inputs" }, { "createpsbt", 1, "outputs" }, { "createpsbt", 2, "locktime" }, diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index 4a918cbd420..d5a5f3ce6f7 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}, }; diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp index 1f3f37d0a0f..122811ce8b5 100644 --- a/src/rpc/util.cpp +++ b/src/rpc/util.cpp @@ -1126,7 +1126,7 @@ std::pair ParseDescriptorRange(const UniValue& value) return {low, high}; } -std::vector EvalDescriptorStringOrObject(const UniValue& scanobject, FlatSigningProvider& provider) +std::vector EvalDescriptorStringOrObject(const UniValue& scanobject, FlatSigningProvider& provider, const bool expand_priv) { std::string desc_str; std::pair range = {0, 1000}; @@ -1159,6 +1159,9 @@ std::vector EvalDescriptorStringOrObject(const UniValue& scanobject, Fl if (!desc->Expand(i, provider, scripts, provider)) { throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, strprintf("Cannot derive script without private keys: '%s'", desc_str)); } + if (expand_priv) { + desc->ExpandPrivate(/*pos=*/i, provider, /*out=*/provider); + } std::move(scripts.begin(), scripts.end(), std::back_inserter(ret)); } return ret; diff --git a/src/rpc/util.h b/src/rpc/util.h index bb5c30a2f44..3ff02582a65 100644 --- a/src/rpc/util.h +++ b/src/rpc/util.h @@ -110,7 +110,7 @@ UniValue JSONRPCTransactionError(TransactionError terr, const std::string& err_s std::pair ParseDescriptorRange(const UniValue& value); /** Evaluate a descriptor given as a string, or as a {"desc":...,"range":...} object, with default range of 1000. */ -std::vector EvalDescriptorStringOrObject(const UniValue& scanobject, FlatSigningProvider& provider); +std::vector EvalDescriptorStringOrObject(const UniValue& scanobject, FlatSigningProvider& provider, const bool expand_priv = false); /** Returns, given services flags, a list of humanly readable (known) network services */ UniValue GetServicesNames(ServiceFlags services); diff --git a/src/test/fuzz/rpc.cpp b/src/test/fuzz/rpc.cpp index 1c6140c66a0..ed0195c5509 100644 --- a/src/test/fuzz/rpc.cpp +++ b/src/test/fuzz/rpc.cpp @@ -97,6 +97,7 @@ const std::vector RPC_COMMANDS_SAFE_FOR_FUZZING{ "decoderawtransaction", "decodescript", "deriveaddresses", + "descriptorprocesspsbt", "disconnectnode", "echo", "echojson", From 1bce12acd3e271a7c88d9400b4e3a5645bc8a911 Mon Sep 17 00:00:00 2001 From: ishaanam Date: Fri, 5 May 2023 11:22:05 -0400 Subject: [PATCH 2/2] test: add test for `descriptorprocesspsbt` RPC --- test/functional/rpc_psbt.py | 47 ++++++++++++++++++++++++++++++++++++- 1 file changed, 46 insertions(+), 1 deletion(-) diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py index ef773463d81..51ea0216b63 100755 --- a/test/functional/rpc_psbt.py +++ b/test/functional/rpc_psbt.py @@ -42,7 +42,10 @@ find_vout_for_address, random_bytes, ) -from test_framework.wallet_util import bytes_to_wif +from test_framework.wallet_util import ( + bytes_to_wif, + get_generate_key +) import json import os @@ -944,6 +947,48 @@ def test_psbt_input_keys(psbt_input, keys): self.log.info("Test we don't crash when making a 0-value funded transaction at 0 fee without forcing an input selection") assert_raises_rpc_error(-4, "Transaction requires one destination of non-0 value, a non-0 feerate, or a pre-selected input", self.nodes[0].walletcreatefundedpsbt, [], [{"data": "deadbeef"}], 0, {"fee_rate": "0"}) + self.log.info("Test descriptorprocesspsbt updates and signs a psbt with descriptors") + + self.generate(self.nodes[2], 1) + + # Disable the wallet for node 2 since `descriptorprocesspsbt` does not use the wallet + self.restart_node(2, extra_args=["-disablewallet"]) + self.connect_nodes(0, 2) + self.connect_nodes(1, 2) + + key_info = get_generate_key() + key = key_info.privkey + address = key_info.p2wpkh_addr + + descriptor = descsum_create(f"wpkh({key})") + + txid = self.nodes[0].sendtoaddress(address, 1) + self.sync_all() + vout = find_output(self.nodes[0], txid, 1) + + psbt = self.nodes[2].createpsbt([{"txid": txid, "vout": vout}], {self.nodes[0].getnewaddress(): 0.99999}) + decoded = self.nodes[2].decodepsbt(psbt) + test_psbt_input_keys(decoded['inputs'][0], []) + + # Test that even if the wrong descriptor is given, `witness_utxo` and `non_witness_utxo` + # are still added to the psbt + alt_descriptor = descsum_create(f"wpkh({get_generate_key().privkey})") + alt_psbt = self.nodes[2].descriptorprocesspsbt(psbt=psbt, descriptors=[alt_descriptor], sighashtype="ALL")["psbt"] + decoded = self.nodes[2].decodepsbt(alt_psbt) + test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'non_witness_utxo']) + + # Test that the psbt is not finalized and does not have bip32_derivs unless specified + psbt = self.nodes[2].descriptorprocesspsbt(psbt=psbt, descriptors=[descriptor], sighashtype="ALL", bip32derivs=True, finalize=False)["psbt"] + decoded = self.nodes[2].decodepsbt(psbt) + test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'non_witness_utxo', 'partial_signatures', 'bip32_derivs']) + + psbt = self.nodes[2].descriptorprocesspsbt(psbt=psbt, descriptors=[descriptor], sighashtype="ALL", bip32derivs=False, finalize=True)["psbt"] + decoded = self.nodes[2].decodepsbt(psbt) + test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'non_witness_utxo', 'final_scriptwitness']) + + # Broadcast transaction + rawtx = self.nodes[2].finalizepsbt(psbt)["hex"] + self.nodes[2].sendrawtransaction(rawtx) if __name__ == '__main__': PSBTTest().main()