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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.

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1#ifndef SECP256K1_EXTRAKEYS_H
2#define SECP256K1_EXTRAKEYS_H
3
4#include "secp256k1.h"
5
6#ifdef __cplusplus
7extern "C" {
8#endif
9
10/** Opaque data structure that holds a parsed and valid "x-only" public key.
11 *  An x-only pubkey encodes a point whose Y coordinate is even. It is
12 *  serialized using only its X coordinate (32 bytes). See BIP-340 for more
13 *  information about x-only pubkeys.
14 *
15 *  The exact representation of data inside is implementation defined and not
16 *  guaranteed to be portable between different platforms or versions. It is
17 *  however guaranteed to be 64 bytes in size, and can be safely copied/moved.
18 *  If you need to convert to a format suitable for storage, transmission, use
19 *  use secp256k1_xonly_pubkey_serialize and secp256k1_xonly_pubkey_parse. To
20 *  compare keys, use secp256k1_xonly_pubkey_cmp.
21 */
22typedef struct secp256k1_xonly_pubkey {
23    unsigned char data[64];
24} secp256k1_xonly_pubkey;
25
26/** Opaque data structure that holds a keypair consisting of a secret and a
27 *  public key.
28 *
29 *  The exact representation of data inside is implementation defined and not
30 *  guaranteed to be portable between different platforms or versions. It is
31 *  however guaranteed to be 96 bytes in size, and can be safely copied/moved.
32 */
33typedef struct secp256k1_keypair {
34    unsigned char data[96];
35} secp256k1_keypair;
36
37/** Parse a 32-byte sequence into a xonly_pubkey object.
38 *
39 *  Returns: 1 if the public key was fully valid.
40 *           0 if the public key could not be parsed or is invalid.
41 *
42 *  Args:   ctx: pointer to a context object.
43 *  Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to a
44 *               parsed version of input. If not, it's set to an invalid value.
45 *  In: input32: pointer to a serialized xonly_pubkey.
46 */
47SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_parse(
48    const secp256k1_context *ctx,
49    secp256k1_xonly_pubkey *pubkey,
50    const unsigned char *input32
51) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
52
53/** Serialize an xonly_pubkey object into a 32-byte sequence.
54 *
55 *  Returns: 1 always.
56 *
57 *  Args:     ctx: pointer to a context object.
58 *  Out: output32: pointer to a 32-byte array to place the serialized key in.
59 *  In:    pubkey: pointer to a secp256k1_xonly_pubkey containing an initialized public key.
60 */
61SECP256K1_API int secp256k1_xonly_pubkey_serialize(
62    const secp256k1_context *ctx,
63    unsigned char *output32,
64    const secp256k1_xonly_pubkey *pubkey
65) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
66
67/** Compare two x-only public keys using lexicographic order
68 *
69 *  Returns: <0 if the first public key is less than the second
70 *           >0 if the first public key is greater than the second
71 *           0 if the two public keys are equal
72 *  Args: ctx:      pointer to a context object.
73 *  In:   pubkey1:  first public key to compare
74 *        pubkey2:  second public key to compare
75 */
76SECP256K1_API int secp256k1_xonly_pubkey_cmp(
77    const secp256k1_context *ctx,
78    const secp256k1_xonly_pubkey *pk1,
79    const secp256k1_xonly_pubkey *pk2
80) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
81
82/** Converts a secp256k1_pubkey into a secp256k1_xonly_pubkey.
83 *
84 *  Returns: 1 always.
85 *
86 *  Args:         ctx: pointer to a context object.
87 *  Out: xonly_pubkey: pointer to an x-only public key object for placing the converted public key.
88 *          pk_parity: Ignored if NULL. Otherwise, pointer to an integer that
89 *                     will be set to 1 if the point encoded by xonly_pubkey is
90 *                     the negation of the pubkey and set to 0 otherwise.
91 *  In:        pubkey: pointer to a public key that is converted.
92 */
93SECP256K1_API int secp256k1_xonly_pubkey_from_pubkey(
94    const secp256k1_context *ctx,
95    secp256k1_xonly_pubkey *xonly_pubkey,
96    int *pk_parity,
97    const secp256k1_pubkey *pubkey
98) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
99
100/** Tweak an x-only public key by adding the generator multiplied with tweak32
101 *  to it.
102 *
103 *  Note that the resulting point can not in general be represented by an x-only
104 *  pubkey because it may have an odd Y coordinate. Instead, the output_pubkey
105 *  is a normal secp256k1_pubkey.
106 *
107 *  Returns: 0 if the arguments are invalid or the resulting public key would be
108 *           invalid (only when the tweak is the negation of the corresponding
109 *           secret key). 1 otherwise.
110 *
111 *  Args:           ctx: pointer to a context object.
112 *  Out:  output_pubkey: pointer to a public key to store the result. Will be set
113 *                       to an invalid value if this function returns 0.
114 *  In: internal_pubkey: pointer to an x-only pubkey to apply the tweak to.
115 *              tweak32: pointer to a 32-byte tweak, which must be valid
116 *                       according to secp256k1_ec_seckey_verify or 32 zero
117 *                       bytes. For uniformly random 32-byte tweaks, the chance of
118 *                       being invalid is negligible (around 1 in 2^128).
119 */
120SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_tweak_add(
121    const secp256k1_context *ctx,
122    secp256k1_pubkey *output_pubkey,
123    const secp256k1_xonly_pubkey *internal_pubkey,
124    const unsigned char *tweak32
125) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
126
127/** Checks that a tweaked pubkey is the result of calling
128 *  secp256k1_xonly_pubkey_tweak_add with internal_pubkey and tweak32.
129 *
130 *  The tweaked pubkey is represented by its 32-byte x-only serialization and
131 *  its pk_parity, which can both be obtained by converting the result of
132 *  tweak_add to a secp256k1_xonly_pubkey.
133 *
134 *  Note that this alone does _not_ verify that the tweaked pubkey is a
135 *  commitment. If the tweak is not chosen in a specific way, the tweaked pubkey
136 *  can easily be the result of a different internal_pubkey and tweak.
137 *
138 *  Returns: 0 if the arguments are invalid or the tweaked pubkey is not the
139 *           result of tweaking the internal_pubkey with tweak32. 1 otherwise.
140 *  Args:            ctx: pointer to a context object.
141 *  In: tweaked_pubkey32: pointer to a serialized xonly_pubkey.
142 *     tweaked_pk_parity: the parity of the tweaked pubkey (whose serialization
143 *                        is passed in as tweaked_pubkey32). This must match the
144 *                        pk_parity value that is returned when calling
145 *                        secp256k1_xonly_pubkey with the tweaked pubkey, or
146 *                        this function will fail.
147 *       internal_pubkey: pointer to an x-only public key object to apply the tweak to.
148 *               tweak32: pointer to a 32-byte tweak.
149 */
150SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_tweak_add_check(
151    const secp256k1_context *ctx,
152    const unsigned char *tweaked_pubkey32,
153    int tweaked_pk_parity,
154    const secp256k1_xonly_pubkey *internal_pubkey,
155    const unsigned char *tweak32
156) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5);
157
158/** Compute the keypair for a valid secret key.
159 *
160 *  See the documentation of `secp256k1_ec_seckey_verify` for more information
161 *  about the validity of secret keys.
162 *
163 *  Returns: 1: secret key is valid
164 *           0: secret key is invalid
165 *  Args:    ctx: pointer to a context object (not secp256k1_context_static).
166 *  Out: keypair: pointer to the created keypair.
167 *  In:   seckey: pointer to a 32-byte secret key.
168 */
169SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_create(
170    const secp256k1_context *ctx,
171    secp256k1_keypair *keypair,
172    const unsigned char *seckey
173) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
174
175/** Get the secret key from a keypair.
176 *
177 *  Returns: 1 always.
178 *  Args:   ctx: pointer to a context object.
179 *  Out: seckey: pointer to a 32-byte buffer for the secret key.
180 *  In: keypair: pointer to a keypair.
181 */
182SECP256K1_API int secp256k1_keypair_sec(
183    const secp256k1_context *ctx,
184    unsigned char *seckey,
185    const secp256k1_keypair *keypair
186) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
187
188/** Get the public key from a keypair.
189 *
190 *  Returns: 1 always.
191 *  Args:   ctx: pointer to a context object.
192 *  Out: pubkey: pointer to a pubkey object, set to the keypair public key.
193 *  In: keypair: pointer to a keypair.
194 */
195SECP256K1_API int secp256k1_keypair_pub(
196    const secp256k1_context *ctx,
197    secp256k1_pubkey *pubkey,
198    const secp256k1_keypair *keypair
199) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
200
201/** Get the x-only public key from a keypair.
202 *
203 *  This is the same as calling secp256k1_keypair_pub and then
204 *  secp256k1_xonly_pubkey_from_pubkey.
205 *
206 *  Returns: 1 always.
207 *  Args:   ctx: pointer to a context object.
208 *  Out: pubkey: pointer to an xonly_pubkey object, set to the keypair
209 *               public key after converting it to an xonly_pubkey.
210 *    pk_parity: Ignored if NULL. Otherwise, pointer to an integer that will be set to the
211 *               pk_parity argument of secp256k1_xonly_pubkey_from_pubkey.
212 *  In: keypair: pointer to a keypair.
213 */
214SECP256K1_API int secp256k1_keypair_xonly_pub(
215    const secp256k1_context *ctx,
216    secp256k1_xonly_pubkey *pubkey,
217    int *pk_parity,
218    const secp256k1_keypair *keypair
219) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
220
221/** Tweak a keypair by adding tweak32 to the secret key and updating the public
222 *  key accordingly.
223 *
224 *  Calling this function and then secp256k1_keypair_pub results in the same
225 *  public key as calling secp256k1_keypair_xonly_pub and then
226 *  secp256k1_xonly_pubkey_tweak_add.
227 *
228 *  Returns: 0 if the arguments are invalid or the resulting keypair would be
229 *           invalid (only when the tweak is the negation of the keypair's
230 *           secret key). 1 otherwise.
231 *
232 *  Args:       ctx: pointer to a context object.
233 *  In/Out: keypair: pointer to a keypair to apply the tweak to. Will be set to
234 *                   an invalid value if this function returns 0.
235 *  In:     tweak32: pointer to a 32-byte tweak, which must be valid according to
236 *                   secp256k1_ec_seckey_verify or 32 zero bytes. For uniformly
237 *                   random 32-byte tweaks, the chance of being invalid is
238 *                   negligible (around 1 in 2^128).
239 */
240SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_xonly_tweak_add(
241    const secp256k1_context *ctx,
242    secp256k1_keypair *keypair,
243    const unsigned char *tweak32
244) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
245
246#ifdef __cplusplus
247}
248#endif
249
250#endif /* SECP256K1_EXTRAKEYS_H */

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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