From a5b4883fb43d01bfef1244df62c64bf8691ca63a Mon Sep 17 00:00:00 2001 From: ishaanam Date: Wed, 27 Jul 2022 14:24:19 +0530 Subject: [PATCH 1/2] rpc: extract psbt updating logic into ProcessPSBT This function is called from utxoupdatepsbt and will be modified in a following commit to allow for updating inputs with the `non_witness_utxo` as well. --- src/rpc/rawtransaction.cpp | 115 ++++++++++++++++++++----------------- 1 file changed, 62 insertions(+), 53 deletions(-) diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index 981dead3b85..011983a158c 100644 --- a/src/rpc/rawtransaction.cpp +++ b/src/rpc/rawtransaction.cpp @@ -169,6 +169,63 @@ static std::vector CreateTxDoc() }; } +// Update PSBT with information from the mempool, the UTXO set, and the provided descriptors +PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std::any& context, const HidingSigningProvider& provider) +{ + // Unserialize the transactions + PartiallySignedTransaction psbtx; + std::string error; + if (!DecodeBase64PSBT(psbtx, psbt_string, error)) { + throw JSONRPCError(RPC_DESERIALIZATION_ERROR, strprintf("TX decode failed %s", error)); + } + + // Fetch previous transactions (inputs): + CCoinsView viewDummy; + CCoinsViewCache view(&viewDummy); + { + NodeContext& node = EnsureAnyNodeContext(context); + const CTxMemPool& mempool = EnsureMemPool(node); + ChainstateManager& chainman = EnsureChainman(node); + LOCK2(cs_main, mempool.cs); + CCoinsViewCache &viewChain = chainman.ActiveChainstate().CoinsTip(); + CCoinsViewMemPool viewMempool(&viewChain, mempool); + view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view + + for (const CTxIn& txin : psbtx.tx->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 + } + + // Fill the inputs + const PrecomputedTransactionData txdata = PrecomputePSBTData(psbtx); + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + PSBTInput& input = psbtx.inputs.at(i); + + if (input.non_witness_utxo || !input.witness_utxo.IsNull()) { + continue; + } + + const Coin& coin = view.AccessCoin(psbtx.tx->vin[i].prevout); + + if (IsSegWitOutput(provider, coin.out.scriptPubKey)) { + input.witness_utxo = coin.out; + } + + // 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, i, &txdata, /*sighash=*/1); + } + + // Update script/keypath information using descriptor data. + for (unsigned int i = 0; i < psbtx.tx->vout.size(); ++i) { + UpdatePSBTOutput(provider, psbtx, i); + } + return psbtx; +} + static RPCHelpMan getrawtransaction() { return RPCHelpMan{ @@ -1594,13 +1651,6 @@ static RPCHelpMan utxoupdatepsbt() }, [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue { - // Unserialize the transactions - PartiallySignedTransaction psbtx; - std::string error; - if (!DecodeBase64PSBT(psbtx, request.params[0].get_str(), error)) { - throw JSONRPCError(RPC_DESERIALIZATION_ERROR, strprintf("TX decode failed %s", error)); - } - // Parse descriptors, if any. FlatSigningProvider provider; if (!request.params[1].isNull()) { @@ -1609,53 +1659,12 @@ static RPCHelpMan utxoupdatepsbt() EvalDescriptorStringOrObject(descs[i], provider); } } + // We don't actually need private keys further on; hide them as a precaution. - HidingSigningProvider public_provider(&provider, /*hide_secret=*/true, /*hide_origin=*/false); - - // Fetch previous transactions (inputs): - CCoinsView viewDummy; - CCoinsViewCache view(&viewDummy); - { - NodeContext& node = EnsureAnyNodeContext(request.context); - const CTxMemPool& mempool = EnsureMemPool(node); - ChainstateManager& chainman = EnsureChainman(node); - LOCK2(cs_main, mempool.cs); - CCoinsViewCache &viewChain = chainman.ActiveChainstate().CoinsTip(); - CCoinsViewMemPool viewMempool(&viewChain, mempool); - view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view - - for (const CTxIn& txin : psbtx.tx->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 - } - - // Fill the inputs - const PrecomputedTransactionData txdata = PrecomputePSBTData(psbtx); - for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { - PSBTInput& input = psbtx.inputs.at(i); - - if (input.non_witness_utxo || !input.witness_utxo.IsNull()) { - continue; - } - - const Coin& coin = view.AccessCoin(psbtx.tx->vin[i].prevout); - - if (IsSegWitOutput(provider, coin.out.scriptPubKey)) { - input.witness_utxo = coin.out; - } - - // 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(public_provider, psbtx, i, &txdata, /*sighash=*/1); - } - - // Update script/keypath information using descriptor data. - for (unsigned int i = 0; i < psbtx.tx->vout.size(); ++i) { - UpdatePSBTOutput(public_provider, psbtx, i); - } + const PartiallySignedTransaction& psbtx = ProcessPSBT( + request.params[0].get_str(), + request.context, + HidingSigningProvider(&provider, /*hide_secret=*/true, /*hide_origin=*/false)); CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION); ssTx << psbtx; From 6e9f8bb050785dbc754b6bb493aad9139908ef98 Mon Sep 17 00:00:00 2001 From: ishaanam Date: Tue, 23 Aug 2022 15:24:00 -0400 Subject: [PATCH 2/2] rpc, tests: in `utxoupdatepsbt` also look for the transaction in the txindex Previously only the segwit utxos being spent by the psbt were looked for and added to the psbt. Now, the full transaction corresponding to each of these utxos (legacy and segwit) is looked for in the txindex and mempool and added to the psbt. If txindex is disabled and the transaction is not in the mempool, then we fall back to getting just the utxo (if segwit) from the utxo set. --- src/psbt.cpp | 32 +++++++++++++++ src/psbt.h | 3 ++ src/rpc/rawtransaction.cpp | 82 +++++++++++++++++++++++++------------ src/wallet/wallet.cpp | 29 +------------ test/functional/rpc_psbt.py | 12 +++--- 5 files changed, 97 insertions(+), 61 deletions(-) diff --git a/src/psbt.cpp b/src/psbt.cpp index 50ccd9e2c03..16f4fa857c1 100644 --- a/src/psbt.cpp +++ b/src/psbt.cpp @@ -430,6 +430,38 @@ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& return sig_complete; } +void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx, const int& sighash_type) +{ + // Only drop non_witness_utxos if sighash_type != SIGHASH_ANYONECANPAY + if ((sighash_type & 0x80) != SIGHASH_ANYONECANPAY) { + // Figure out if any non_witness_utxos should be dropped + std::vector to_drop; + for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) { + const auto& input = psbtx.inputs.at(i); + int wit_ver; + std::vector wit_prog; + if (input.witness_utxo.IsNull() || !input.witness_utxo.scriptPubKey.IsWitnessProgram(wit_ver, wit_prog)) { + // There's a non-segwit input or Segwit v0, so we cannot drop any witness_utxos + to_drop.clear(); + break; + } + if (wit_ver == 0) { + // Segwit v0, so we cannot drop any non_witness_utxos + to_drop.clear(); + break; + } + if (input.non_witness_utxo) { + to_drop.push_back(i); + } + } + + // Drop the non_witness_utxos that we can drop + for (unsigned int i : to_drop) { + psbtx.inputs.at(i).non_witness_utxo = nullptr; + } + } +} + bool FinalizePSBT(PartiallySignedTransaction& psbtx) { // Finalize input signatures -- in case we have partial signatures that add up to a complete diff --git a/src/psbt.h b/src/psbt.h index 40d69cd4545..0a581933f0e 100644 --- a/src/psbt.h +++ b/src/psbt.h @@ -1231,6 +1231,9 @@ bool PSBTInputSignedAndVerified(const PartiallySignedTransaction psbt, unsigned **/ bool SignPSBTInput(const SigningProvider& provider, PartiallySignedTransaction& psbt, int index, const PrecomputedTransactionData* txdata, int sighash = SIGHASH_ALL, SignatureData* out_sigdata = nullptr, bool finalize = true); +/** Reduces the size of the PSBT by dropping unnecessary `non_witness_utxos` (i.e. complete previous transactions) from a psbt when all inputs are segwit v1. */ +void RemoveUnnecessaryTransactions(PartiallySignedTransaction& psbtx, const int& sighash_type); + /** Counts the unsigned inputs of a PSBT. */ size_t CountPSBTUnsignedInputs(const PartiallySignedTransaction& psbt); diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp index 011983a158c..879e847acb3 100644 --- a/src/rpc/rawtransaction.cpp +++ b/src/rpc/rawtransaction.cpp @@ -169,7 +169,7 @@ static std::vector CreateTxDoc() }; } -// Update PSBT with information from the mempool, the UTXO set, and the provided descriptors +// 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) { // Unserialize the transactions @@ -179,50 +179,78 @@ PartiallySignedTransaction ProcessPSBT(const std::string& psbt_string, const std throw JSONRPCError(RPC_DESERIALIZATION_ERROR, strprintf("TX decode failed %s", error)); } - // Fetch previous transactions (inputs): - CCoinsView viewDummy; - CCoinsViewCache view(&viewDummy); - { - NodeContext& node = EnsureAnyNodeContext(context); - const CTxMemPool& mempool = EnsureMemPool(node); - ChainstateManager& chainman = EnsureChainman(node); - LOCK2(cs_main, mempool.cs); - CCoinsViewCache &viewChain = chainman.ActiveChainstate().CoinsTip(); - CCoinsViewMemPool viewMempool(&viewChain, mempool); - view.SetBackend(viewMempool); // temporarily switch cache backend to db+mempool view + if (g_txindex) g_txindex->BlockUntilSyncedToCurrentChain(); + const NodeContext& node = EnsureAnyNodeContext(context); - for (const CTxIn& txin : psbtx.tx->vin) { - view.AccessCoin(txin.prevout); // Load entries from viewChain into view; can fail. + // If we can't find the corresponding full transaction for all of our inputs, + // this will be used to find just the utxos for the segwit inputs for which + // the full transaction isn't found + std::map coins; + + // Fetch previous transactions: + // First, look in the txindex and the mempool + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + PSBTInput& psbt_input = psbtx.inputs.at(i); + const CTxIn& tx_in = psbtx.tx->vin.at(i); + + // The `non_witness_utxo` is the whole previous transaction + if (psbt_input.non_witness_utxo) continue; + + CTransactionRef tx; + + // Look in the txindex + if (g_txindex) { + uint256 block_hash; + g_txindex->FindTx(tx_in.prevout.hash, block_hash, tx); + } + // If we still don't have it look in the mempool + if (!tx) { + tx = node.mempool->get(tx_in.prevout.hash); + } + if (tx) { + psbt_input.non_witness_utxo = tx; + } else { + coins[tx_in.prevout]; // Create empty map entry keyed by prevout } - - view.SetBackend(viewDummy); // switch back to avoid locking mempool for too long } - // Fill the inputs - const PrecomputedTransactionData txdata = PrecomputePSBTData(psbtx); - for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { - PSBTInput& input = psbtx.inputs.at(i); + // If we still haven't found all of the inputs, look for the missing ones in the utxo set + if (!coins.empty()) { + FindCoins(node, coins); + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + PSBTInput& input = psbtx.inputs.at(i); - if (input.non_witness_utxo || !input.witness_utxo.IsNull()) { - continue; + // If there are still missing utxos, add them if they were found in the utxo set + if (!input.non_witness_utxo) { + const CTxIn& tx_in = psbtx.tx->vin.at(i); + const Coin& coin = coins.at(tx_in.prevout); + if (!coin.out.IsNull() && IsSegWitOutput(provider, coin.out.scriptPubKey)) { + input.witness_utxo = coin.out; + } + } } + } - const Coin& coin = view.AccessCoin(psbtx.tx->vin[i].prevout); + const PrecomputedTransactionData& txdata = PrecomputePSBTData(psbtx); - if (IsSegWitOutput(provider, coin.out.scriptPubKey)) { - input.witness_utxo = coin.out; + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + if (PSBTInputSigned(psbtx.inputs.at(i))) { + continue; } // 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, i, &txdata, /*sighash=*/1); + SignPSBTInput(provider, psbtx, /*index=*/i, &txdata, /*sighash=*/1); } // Update script/keypath information using descriptor data. for (unsigned int i = 0; i < psbtx.tx->vout.size(); ++i) { UpdatePSBTOutput(provider, psbtx, i); } + + RemoveUnnecessaryTransactions(psbtx, /*sighash_type=*/1); + return psbtx; } @@ -1632,7 +1660,7 @@ static RPCHelpMan converttopsbt() static RPCHelpMan utxoupdatepsbt() { return RPCHelpMan{"utxoupdatepsbt", - "\nUpdates all segwit inputs and outputs in a PSBT with data from output descriptors, the UTXO set or the mempool.\n", + "\nUpdates all segwit inputs and outputs in a PSBT with data from output descriptors, the UTXO set, txindex, or the mempool.\n", { {"psbt", RPCArg::Type::STR, RPCArg::Optional::NO, "A base64 string of a PSBT"}, {"descriptors", RPCArg::Type::ARR, RPCArg::Optional::OMITTED_NAMED_ARG, "An array of either strings or objects", { diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp index 6158ff033ca..3ead8bee349 100644 --- a/src/wallet/wallet.cpp +++ b/src/wallet/wallet.cpp @@ -2156,34 +2156,7 @@ TransactionError CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& comp } } - // Only drop non_witness_utxos if sighash_type != SIGHASH_ANYONECANPAY - if ((sighash_type & 0x80) != SIGHASH_ANYONECANPAY) { - // Figure out if any non_witness_utxos should be dropped - std::vector to_drop; - for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) { - const auto& input = psbtx.inputs.at(i); - int wit_ver; - std::vector wit_prog; - if (input.witness_utxo.IsNull() || !input.witness_utxo.scriptPubKey.IsWitnessProgram(wit_ver, wit_prog)) { - // There's a non-segwit input or Segwit v0, so we cannot drop any witness_utxos - to_drop.clear(); - break; - } - if (wit_ver == 0) { - // Segwit v0, so we cannot drop any non_witness_utxos - to_drop.clear(); - break; - } - if (input.non_witness_utxo) { - to_drop.push_back(i); - } - } - - // Drop the non_witness_utxos that we can drop - for (unsigned int i : to_drop) { - psbtx.inputs.at(i).non_witness_utxo = nullptr; - } - } + RemoveUnnecessaryTransactions(psbtx, sighash_type); // Complete if every input is now signed complete = true; diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py index 58a80e37a20..44113296882 100755 --- a/test/functional/rpc_psbt.py +++ b/test/functional/rpc_psbt.py @@ -611,17 +611,17 @@ class PSBTTest(BitcoinTestFramework): # Bech32 inputs should be filled with witness UTXO. Other inputs should not be filled because they are non-witness updated = self.nodes[1].utxoupdatepsbt(psbt) decoded = self.nodes[1].decodepsbt(updated) - test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo']) - test_psbt_input_keys(decoded['inputs'][1], []) - test_psbt_input_keys(decoded['inputs'][2], []) + test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'non_witness_utxo']) + test_psbt_input_keys(decoded['inputs'][1], ['non_witness_utxo']) + test_psbt_input_keys(decoded['inputs'][2], ['non_witness_utxo']) # Try again, now while providing descriptors, making P2SH-segwit work, and causing bip32_derivs and redeem_script to be filled in descs = [self.nodes[1].getaddressinfo(addr)['desc'] for addr in [addr1,addr2,addr3]] updated = self.nodes[1].utxoupdatepsbt(psbt=psbt, descriptors=descs) decoded = self.nodes[1].decodepsbt(updated) - test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'bip32_derivs']) - test_psbt_input_keys(decoded['inputs'][1], []) - test_psbt_input_keys(decoded['inputs'][2], ['witness_utxo', 'bip32_derivs', 'redeem_script']) + test_psbt_input_keys(decoded['inputs'][0], ['witness_utxo', 'non_witness_utxo', 'bip32_derivs']) + test_psbt_input_keys(decoded['inputs'][1], ['non_witness_utxo', 'bip32_derivs']) + test_psbt_input_keys(decoded['inputs'][2], ['non_witness_utxo','witness_utxo', 'bip32_derivs', 'redeem_script']) # Two PSBTs with a common input should not be joinable psbt1 = self.nodes[1].createpsbt([{"txid":txid1, "vout":vout1}], {self.nodes[0].getnewaddress():Decimal('10.999')})