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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

6,017 bytes · SHA-256 81a48f5564e28f4a… · View upstream ↗

1// Copyright (c) 2009-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <coins.h>
6#include <consensus/amount.h>
7#include <consensus/tx_verify.h>
8#include <node/psbt.h>
9#include <policy/policy.h>
10#include <policy/settings.h>
11#include <tinyformat.h>
12
13#include <numeric>
14
15namespace node {
16PSBTAnalysis AnalyzePSBT(PartiallySignedTransaction psbtx)
17{
18    // Go through each input and build status
19    PSBTAnalysis result;
20
21    std::optional<CMutableTransaction> unsigned_tx = psbtx.GetUnsignedTx();
22    if (!unsigned_tx) {
23        result.SetInvalid("PSBT cannot be made into a valid transaction");
24        return result;
25    }
26    CMutableTransaction& mtx = *unsigned_tx;
27
28    bool calc_fee = true;
29
30    CAmount in_amt = 0;
31
32    result.inputs.resize(psbtx.inputs.size());
33
34    // PrecomputePSBTData calls GetUnsignedTx() which we checked already works
35    const PrecomputedTransactionData txdata = *PrecomputePSBTData(psbtx);
36
37    for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) {
38        PSBTInput& input = psbtx.inputs[i];
39        PSBTInputAnalysis& input_analysis = result.inputs[i];
40
41        // We set next role here and ratchet backwards as required
42        input_analysis.next = PSBTRole::EXTRACTOR;
43
44        // Check for a UTXO
45        CTxOut utxo;
46        if (input.GetUTXO(utxo)) {
47            if (!MoneyRange(utxo.nValue) || !MoneyRange(in_amt + utxo.nValue)) {
48                result.SetInvalid(strprintf("PSBT is not valid. Input %u has invalid value", i));
49                return result;
50            }
51            in_amt += utxo.nValue;
52            input_analysis.has_utxo = true;
53        } else {
54            if (input.non_witness_utxo && input.prev_out >= input.non_witness_utxo->vout.size()) {
55                result.SetInvalid(strprintf("PSBT is not valid. Input %u specifies invalid prevout", i));
56                return result;
57            }
58            input_analysis.has_utxo = false;
59            input_analysis.is_final = false;
60            input_analysis.next = PSBTRole::UPDATER;
61            calc_fee = false;
62        }
63
64        if (!utxo.IsNull() && utxo.scriptPubKey.IsUnspendable()) {
65            result.SetInvalid(strprintf("PSBT is not valid. Input %u spends unspendable output", i));
66            return result;
67        }
68
69        // Check if it is final
70        if (!PSBTInputSignedAndVerified(psbtx, i, &txdata)) {
71            input_analysis.is_final = false;
72
73            // Figure out what is missing
74            SignatureData outdata;
75            const auto sign_result = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, &txdata, /*options*/{}, &outdata);
76            bool complete = sign_result.has_value();
77
78            // Things are missing
79            if (!complete) {
80                input_analysis.missing_pubkeys = outdata.missing_pubkeys;
81                input_analysis.missing_redeem_script = outdata.missing_redeem_script;
82                input_analysis.missing_witness_script = outdata.missing_witness_script;
83                input_analysis.missing_sigs = outdata.missing_sigs;
84
85                // If we are only missing signatures and nothing else, then next is signer
86                if (outdata.missing_pubkeys.empty() && outdata.missing_redeem_script.IsNull() && outdata.missing_witness_script.IsNull() && !outdata.missing_sigs.empty()) {
87                    input_analysis.next = PSBTRole::SIGNER;
88                } else {
89                    input_analysis.next = PSBTRole::UPDATER;
90                }
91            } else {
92                input_analysis.next = PSBTRole::FINALIZER;
93            }
94        } else if (!utxo.IsNull()){
95            input_analysis.is_final = true;
96        }
97    }
98
99    // Calculate next role for PSBT by grabbing "minimum" PSBTInput next role
100    result.next = PSBTRole::EXTRACTOR;
101    for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) {
102        PSBTInputAnalysis& input_analysis = result.inputs[i];
103        result.next = std::min(result.next, input_analysis.next);
104    }
105    assert(result.next > PSBTRole::CREATOR);
106
107    if (calc_fee) {
108        // Get the output amount
109        CAmount out_amt = std::accumulate(psbtx.outputs.begin(), psbtx.outputs.end(), CAmount(0),
110            [](CAmount a, const PSBTOutput& b) {
111                if (!MoneyRange(a) || !MoneyRange(b.amount) || !MoneyRange(a + b.amount)) {
112                    return CAmount(-1);
113                }
114                return a += b.amount;
115            }
116        );
117        if (!MoneyRange(out_amt)) {
118            result.SetInvalid("PSBT is not valid. Output amount invalid");
119            return result;
120        }
121
122        // Get the fee
123        CAmount fee = in_amt - out_amt;
124        result.fee = fee;
125
126        // Estimate the size
127        CCoinsViewCache view{&CoinsViewEmpty::Get()};
128        bool success = true;
129
130        for (unsigned int i = 0; i < psbtx.inputs.size(); ++i) {
131            PSBTInput& input = psbtx.inputs[i];
132            Coin newcoin;
133
134            const auto sign_result = SignPSBTInput(DUMMY_SIGNING_PROVIDER, psbtx, i, nullptr, /*options=*/{});
135            if (!sign_result.has_value() || !input.GetUTXO(newcoin.out)) {
136                success = false;
137                break;
138            } else {
139                mtx.vin[i].scriptSig = input.final_script_sig;
140                mtx.vin[i].scriptWitness = input.final_script_witness;
141                newcoin.nHeight = 1;
142                view.AddCoin(input.GetOutPoint(), std::move(newcoin), true);
143            }
144        }
145
146        if (success) {
147            CTransaction ctx = CTransaction(mtx);
148            size_t size(GetVirtualTransactionSize(ctx, GetTransactionSigOpCost(ctx, view, STANDARD_SCRIPT_VERIFY_FLAGS), ::nBytesPerSigOp));
149            result.estimated_vsize = size;
150            // Estimate fee rate
151            CFeeRate feerate(fee, size);
152            result.estimated_feerate = feerate;
153        }
154
155    }
156
157    return result;
158}
159} // namespace node
160

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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