READ THE CODE

Inside Bitcoin

The code behind the network, with room to understand it.

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.

70,656 bytes · SHA-256 cc7139b01872981a… · 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#ifndef BITCOIN_PSBT_H
6#define BITCOIN_PSBT_H
7
8#include <common/types.h>
9#include <musig.h>
10#include <node/transaction.h>
11#include <policy/feerate.h>
12#include <primitives/transaction.h>
13#include <pubkey.h>
14#include <script/keyorigin.h>
15#include <script/sign.h>
16#include <script/signingprovider.h>
17#include <span.h>
18#include <streams.h>
19#include <uint256.h>
20#include <util/result.h>
21#include <util/expected.h>
22
23#include <optional>
24#include <bitset>
25
26namespace node {
27enum class TransactionError;
28} // namespace node
29
30using common::PSBTError;
31
32// Magic bytes
33inline constexpr uint8_t PSBT_MAGIC_BYTES[5] = {'p', 's', 'b', 't', 0xff};
34
35// Global types
36inline constexpr uint8_t PSBT_GLOBAL_UNSIGNED_TX = 0x00;
37inline constexpr uint8_t PSBT_GLOBAL_XPUB = 0x01;
38inline constexpr uint8_t PSBT_GLOBAL_TX_VERSION = 0x02;
39inline constexpr uint8_t PSBT_GLOBAL_FALLBACK_LOCKTIME = 0x03;
40inline constexpr uint8_t PSBT_GLOBAL_INPUT_COUNT = 0x04;
41inline constexpr uint8_t PSBT_GLOBAL_OUTPUT_COUNT = 0x05;
42inline constexpr uint8_t PSBT_GLOBAL_TX_MODIFIABLE = 0x06;
43inline constexpr uint8_t PSBT_GLOBAL_VERSION = 0xFB;
44inline constexpr uint8_t PSBT_GLOBAL_PROPRIETARY = 0xFC;
45
46// Input types
47inline constexpr uint8_t PSBT_IN_NON_WITNESS_UTXO = 0x00;
48inline constexpr uint8_t PSBT_IN_WITNESS_UTXO = 0x01;
49inline constexpr uint8_t PSBT_IN_PARTIAL_SIG = 0x02;
50inline constexpr uint8_t PSBT_IN_SIGHASH = 0x03;
51inline constexpr uint8_t PSBT_IN_REDEEMSCRIPT = 0x04;
52inline constexpr uint8_t PSBT_IN_WITNESSSCRIPT = 0x05;
53inline constexpr uint8_t PSBT_IN_BIP32_DERIVATION = 0x06;
54inline constexpr uint8_t PSBT_IN_SCRIPTSIG = 0x07;
55inline constexpr uint8_t PSBT_IN_SCRIPTWITNESS = 0x08;
56inline constexpr uint8_t PSBT_IN_RIPEMD160 = 0x0A;
57inline constexpr uint8_t PSBT_IN_SHA256 = 0x0B;
58inline constexpr uint8_t PSBT_IN_HASH160 = 0x0C;
59inline constexpr uint8_t PSBT_IN_HASH256 = 0x0D;
60inline constexpr uint8_t PSBT_IN_PREVIOUS_TXID = 0x0e;
61inline constexpr uint8_t PSBT_IN_OUTPUT_INDEX = 0x0f;
62inline constexpr uint8_t PSBT_IN_SEQUENCE = 0x10;
63inline constexpr uint8_t PSBT_IN_REQUIRED_TIME_LOCKTIME = 0x11;
64inline constexpr uint8_t PSBT_IN_REQUIRED_HEIGHT_LOCKTIME = 0x12;
65inline constexpr uint8_t PSBT_IN_TAP_KEY_SIG = 0x13;
66inline constexpr uint8_t PSBT_IN_TAP_SCRIPT_SIG = 0x14;
67inline constexpr uint8_t PSBT_IN_TAP_LEAF_SCRIPT = 0x15;
68inline constexpr uint8_t PSBT_IN_TAP_BIP32_DERIVATION = 0x16;
69inline constexpr uint8_t PSBT_IN_TAP_INTERNAL_KEY = 0x17;
70inline constexpr uint8_t PSBT_IN_TAP_MERKLE_ROOT = 0x18;
71inline constexpr uint8_t PSBT_IN_MUSIG2_PARTICIPANT_PUBKEYS = 0x1a;
72inline constexpr uint8_t PSBT_IN_MUSIG2_PUB_NONCE = 0x1b;
73inline constexpr uint8_t PSBT_IN_MUSIG2_PARTIAL_SIG = 0x1c;
74inline constexpr uint8_t PSBT_IN_PROPRIETARY = 0xFC;
75
76// Output types
77inline constexpr uint8_t PSBT_OUT_REDEEMSCRIPT = 0x00;
78inline constexpr uint8_t PSBT_OUT_WITNESSSCRIPT = 0x01;
79inline constexpr uint8_t PSBT_OUT_BIP32_DERIVATION = 0x02;
80inline constexpr uint8_t PSBT_OUT_AMOUNT = 0x03;
81inline constexpr uint8_t PSBT_OUT_SCRIPT = 0x04;
82inline constexpr uint8_t PSBT_OUT_TAP_INTERNAL_KEY = 0x05;
83inline constexpr uint8_t PSBT_OUT_TAP_TREE = 0x06;
84inline constexpr uint8_t PSBT_OUT_TAP_BIP32_DERIVATION = 0x07;
85inline constexpr uint8_t PSBT_OUT_MUSIG2_PARTICIPANT_PUBKEYS = 0x08;
86inline constexpr uint8_t PSBT_OUT_PROPRIETARY = 0xFC;
87
88// The separator is 0x00. Reading this in means that the unserializer can interpret it
89// as a 0 length key which indicates that this is the separator. The separator has no value.
90inline constexpr uint8_t PSBT_SEPARATOR = 0x00;
91
92// BIP 174 does not specify a maximum file size, but we set a limit anyway
93// to prevent reading a stream indefinitely and running out of memory.
94inline constexpr std::streamsize MAX_FILE_SIZE_PSBT{100'000'000}; // 100 MB
95
96// PSBT version number
97inline constexpr uint32_t PSBT_HIGHEST_VERSION = 2;
98
99/** A structure for PSBT proprietary types */
100struct PSBTProprietary
101{
102    uint64_t subtype;
103    std::vector<unsigned char> identifier;
104    std::vector<unsigned char> key;
105    std::vector<unsigned char> value;
106
107    bool operator<(const PSBTProprietary &b) const {
108        return key < b.key;
109    }
110    bool operator==(const PSBTProprietary &b) const {
111        return key == b.key;
112    }
113};
114
115// Takes a stream and multiple arguments and serializes them as if first serialized into a vector and then into the stream
116// The resulting output into the stream has the total serialized length of all of the objects followed by all objects concatenated with each other.
117template<typename Stream, typename... X>
118void SerializeToVector(Stream& s, const X&... args)
119{
120    SizeComputer sizecomp;
121    SerializeMany(sizecomp, args...);
122    WriteCompactSize(s, sizecomp.size());
123    SerializeMany(s, args...);
124}
125
126// Takes a stream and multiple arguments and unserializes them first as a vector then each object individually in the order provided in the arguments
127template<typename Stream, typename... X>
128void UnserializeFromVector(Stream& s, X&&... args)
129{
130    size_t expected_size = ReadCompactSize(s);
131    size_t remaining_before = s.size();
132    UnserializeMany(s, args...);
133    size_t remaining_after = s.size();
134    if (remaining_after + expected_size != remaining_before) {
135        throw std::ios_base::failure("Size of value was not the stated size");
136    }
137}
138
139// Deserialize bytes of given length from the stream as a KeyOriginInfo
140template<typename Stream>
141KeyOriginInfo DeserializeKeyOrigin(Stream& s, uint64_t length)
142{
143    // Read in key path
144    if (length % 4 || length == 0) {
145        throw std::ios_base::failure("Invalid length for HD key path");
146    }
147
148    KeyOriginInfo hd_keypath;
149    s >> hd_keypath.fingerprint;
150    for (unsigned int i = 4; i < length; i += sizeof(uint32_t)) {
151        uint32_t index;
152        s >> index;
153        hd_keypath.path.push_back(index);
154    }
155    return hd_keypath;
156}
157
158// Deserialize a length prefixed KeyOriginInfo from a stream
159template<typename Stream>
160void DeserializeHDKeypath(Stream& s, KeyOriginInfo& hd_keypath)
161{
162    hd_keypath = DeserializeKeyOrigin(s, ReadCompactSize(s));
163}
164
165// Deserialize HD keypaths into a map
166template<typename Stream>
167void DeserializeHDKeypaths(Stream& s, const std::vector<unsigned char>& key, std::map<CPubKey, KeyOriginInfo>& hd_keypaths)
168{
169    // Make sure that the key is the size of pubkey + 1
170    if (key.size() != CPubKey::SIZE + 1 && key.size() != CPubKey::COMPRESSED_SIZE + 1) {
171        throw std::ios_base::failure("Size of key was not the expected size for the type BIP32 keypath");
172    }
173    // Read in the pubkey from key
174    CPubKey pubkey(key.begin() + 1, key.end());
175    if (!pubkey.IsFullyValid()) {
176       throw std::ios_base::failure("Invalid pubkey");
177    }
178
179    KeyOriginInfo keypath;
180    DeserializeHDKeypath(s, keypath);
181
182    // Add to map
183    hd_keypaths.emplace(pubkey, std::move(keypath));
184}
185
186// Serialize a KeyOriginInfo to a stream
187template<typename Stream>
188void SerializeKeyOrigin(Stream& s, KeyOriginInfo hd_keypath)
189{
190    s << hd_keypath.fingerprint;
191    for (const auto& path : hd_keypath.path) {
192        s << path;
193    }
194}
195
196// Serialize a length prefixed KeyOriginInfo to a stream
197template<typename Stream>
198void SerializeHDKeypath(Stream& s, KeyOriginInfo hd_keypath)
199{
200    WriteCompactSize(s, (hd_keypath.path.size() + 1) * sizeof(uint32_t));
201    SerializeKeyOrigin(s, hd_keypath);
202}
203
204// Serialize HD keypaths to a stream from a map
205template<typename Stream>
206void SerializeHDKeypaths(Stream& s, const std::map<CPubKey, KeyOriginInfo>& hd_keypaths, CompactSizeWriter type)
207{
208    for (const auto& keypath_pair : hd_keypaths) {
209        if (!keypath_pair.first.IsValid()) {
210            throw std::ios_base::failure("Invalid CPubKey being serialized");
211        }
212        SerializeToVector(s, type, std::span{keypath_pair.first});
213        SerializeHDKeypath(s, keypath_pair.second);
214    }
215}
216
217// Deserialize a PSBT_{IN/OUT}_MUSIG2_PARTICIPANT_PUBKEYS field
218template<typename Stream>
219void DeserializeMuSig2ParticipantPubkeys(Stream& s, SpanReader& skey, std::map<CPubKey, std::vector<CPubKey>>& out, std::string context)
220{
221    std::array<unsigned char, CPubKey::COMPRESSED_SIZE> agg_pubkey_bytes;
222    skey >> std::as_writable_bytes(std::span{agg_pubkey_bytes});
223    CPubKey agg_pubkey(agg_pubkey_bytes);
224    if (!agg_pubkey.IsFullyValid()) {
225        throw std::ios_base::failure(context + " musig2 aggregate pubkey is invalid");
226    }
227
228    std::vector<CPubKey> participants;
229    std::vector<unsigned char> val;
230    s >> val;
231    SpanReader s_val{val};
232    while (s_val.size() >= CPubKey::COMPRESSED_SIZE) {
233        std::array<unsigned char, CPubKey::COMPRESSED_SIZE> part_pubkey_bytes;
234        s_val >> std::as_writable_bytes(std::span{part_pubkey_bytes});
235        CPubKey participant(part_pubkey_bytes);
236        if (!participant.IsFullyValid()) {
237            throw std::ios_base::failure(context + " musig2 participant pubkey is invalid");
238        }
239        participants.push_back(participant);
240    }
241    if (!s_val.empty()) {
242        throw std::ios_base::failure(context + " musig2 participants pubkeys value size is not a multiple of 33");
243    }
244
245    out.emplace(agg_pubkey, participants);
246}
247
248// Deserialize the MuSig2 participant identifiers from PSBT_MUSIG2_{PUBNONCE/PARTIAL_SIG} fields
249// Both fields contain the same data after the type byte - aggregate pubkey | participant pubkey | leaf script hash
250template<typename Stream>

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

Independent explanations by MyBitcoinExplorer. Not affiliated with or endorsed by Bitcoin Core. Guides are educational and do not replace the source or its tests.

Bitcoin Core source © its contributors, distributed under the MIT license. Original notices and bundled third-party licenses are retained in the source tree.