From ef22fe8c1f331b4f13f21a54d12030b92e83fbe7 Mon Sep 17 00:00:00 2001 From: Glenn Willen Date: Fri, 1 Mar 2019 00:25:10 -0800 Subject: Refactor analyzepsbt for use outside RPC code Refactor the analyzepsbt RPC into (1) an AnalyzePSBT function, which returns its output as a new strongly-typed PSBTAnalysis struct, and (2) a thin wrapper which converts the struct into a UniValue for RPC use. --- src/psbt.cpp | 139 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 138 insertions(+), 1 deletion(-) (limited to 'src/psbt.cpp') diff --git a/src/psbt.cpp b/src/psbt.cpp index 734e7897ec..184129e330 100644 --- a/src/psbt.cpp +++ b/src/psbt.cpp @@ -2,9 +2,14 @@ // Distributed under the MIT software license, see the accompanying // file COPYING or http://www.opensource.org/licenses/mit-license.php. +#include +#include +#include #include #include +#include + PartiallySignedTransaction::PartiallySignedTransaction(const CMutableTransaction& tx) : tx(tx) { inputs.resize(tx.vin.size()); @@ -205,7 +210,7 @@ void PSBTOutput::Merge(const PSBTOutput& output) if (redeem_script.empty() && !output.redeem_script.empty()) redeem_script = output.redeem_script; if (witness_script.empty() && !output.witness_script.empty()) witness_script = output.witness_script; } -bool PSBTInputSigned(PSBTInput& input) +bool PSBTInputSigned(const PSBTInput& input) { return !input.final_script_sig.empty() || !input.final_script_witness.IsNull(); } @@ -326,6 +331,138 @@ TransactionError CombinePSBTs(PartiallySignedTransaction& out, const std::vector return TransactionError::OK; } +std::string PSBTRoleName(PSBTRole role) { + switch (role) { + case PSBTRole::UPDATER: return "updater"; + case PSBTRole::SIGNER: return "signer"; + case PSBTRole::FINALIZER: return "finalizer"; + case PSBTRole::EXTRACTOR: return "extractor"; + } +} + +PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx) +{ + // Go through each input and build status + PSBTAnalysis result; + + bool calc_fee = true; + bool all_final = true; + bool only_missing_sigs = true; + bool only_missing_final = false; + CAmount in_amt = 0; + + result.inputs.resize(psbtx.tx->vin.size()); + + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + PSBTInput& input = psbtx.inputs[i]; + PSBTInputAnalysis& input_analysis = result.inputs[i]; + + // Check for a UTXO + CTxOut utxo; + if (psbtx.GetInputUTXO(utxo, i)) { + in_amt += utxo.nValue; + input_analysis.has_utxo = true; + } else { + input_analysis.has_utxo = false; + input_analysis.is_final = false; + input_analysis.next = PSBTRole::UPDATER; + calc_fee = false; + } + + // Check if it is final + if (!utxo.IsNull() && !PSBTInputSigned(input)) { + input_analysis.is_final = false; + all_final = false; + + // Figure out what is missing + SignatureData outdata; + bool complete = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, 1, &outdata); + + // Things are missing + if (!complete) { + input_analysis.missing_pubkeys = outdata.missing_pubkeys; + input_analysis.missing_redeem_script = outdata.missing_redeem_script; + input_analysis.missing_witness_script = outdata.missing_witness_script; + input_analysis.missing_sigs = outdata.missing_sigs; + + // If we are only missing signatures and nothing else, then next is signer + if (outdata.missing_pubkeys.empty() && outdata.missing_redeem_script.IsNull() && outdata.missing_witness_script.IsNull() && !outdata.missing_sigs.empty()) { + input_analysis.next = PSBTRole::SIGNER; + } else { + only_missing_sigs = false; + input_analysis.next = PSBTRole::UPDATER; + } + } else { + only_missing_final = true; + input_analysis.next = PSBTRole::FINALIZER; + } + } else if (!utxo.IsNull()){ + input_analysis.is_final = true; + } + } + + if (all_final) { + only_missing_sigs = false; + result.next = PSBTRole::EXTRACTOR; + } + if (calc_fee) { + // Get the output amount + CAmount out_amt = std::accumulate(psbtx.tx->vout.begin(), psbtx.tx->vout.end(), CAmount(0), + [](CAmount a, const CTxOut& b) { + return a += b.nValue; + } + ); + + // Get the fee + CAmount fee = in_amt - out_amt; + result.fee = fee; + + // Estimate the size + CMutableTransaction mtx(*psbtx.tx); + CCoinsView view_dummy; + CCoinsViewCache view(&view_dummy); + bool success = true; + + for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) { + PSBTInput& input = psbtx.inputs[i]; + Coin newcoin; + + if (!SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, 1, nullptr, true) || !psbtx.GetInputUTXO(newcoin.out, i)) { + success = false; + break; + } else { + mtx.vin[i].scriptSig = input.final_script_sig; + mtx.vin[i].scriptWitness = input.final_script_witness; + newcoin.nHeight = 1; + view.AddCoin(psbtx.tx->vin[i].prevout, std::move(newcoin), true); + } + } + + if (success) { + CTransaction ctx = CTransaction(mtx); + size_t size = GetVirtualTransactionSize(ctx, GetTransactionSigOpCost(ctx, view, STANDARD_SCRIPT_VERIFY_FLAGS)); + result.estimated_vsize = size; + // Estimate fee rate + CFeeRate feerate(fee, size); + result.estimated_feerate = feerate; + } + + if (only_missing_sigs) { + result.next = PSBTRole::SIGNER; + } else if (only_missing_final) { + result.next = PSBTRole::FINALIZER; + } else if (all_final) { + result.next = PSBTRole::EXTRACTOR; + } else { + result.next = PSBTRole::UPDATER; + } + } else { + result.next = PSBTRole::UPDATER; + } + + return result; +} + bool DecodeBase64PSBT(PartiallySignedTransaction& psbt, const std::string& base64_tx, std::string& error) { bool invalid; -- cgit v1.2.3