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

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1#ifndef SECP256K1_SCHNORRSIG_H
2#define SECP256K1_SCHNORRSIG_H
3
4#include "secp256k1.h"
5#include "secp256k1_extrakeys.h"
6
7#ifdef __cplusplus
8extern "C" {
9#endif
10
11/** This module implements a variant of Schnorr signatures compliant with
12 *  Bitcoin Improvement Proposal 340 "Schnorr Signatures for secp256k1"
13 *  (https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
14 */
15
16/** A pointer to a function to deterministically generate a nonce.
17 *
18 *  Same as secp256k1_nonce function with the exception of accepting an
19 *  additional pubkey argument and not requiring an attempt argument. The pubkey
20 *  argument can protect signature schemes with key-prefixed challenge hash
21 *  inputs against reusing the nonce when signing with the wrong precomputed
22 *  pubkey.
23 *
24 *  Returns: 1 if a nonce was successfully generated. 0 will cause signing to
25 *           return an error.
26 *  Out:  nonce32: pointer to a 32-byte array to be filled by the function
27 *  In:       msg: the message being verified. Is NULL if and only if msglen
28 *                 is 0.
29 *         msglen: the length of the message
30 *          key32: pointer to a 32-byte secret key (will not be NULL)
31 *     xonly_pk32: the 32-byte serialized xonly pubkey corresponding to key32
32 *                 (will not be NULL)
33 *           algo: pointer to an array describing the signature
34 *                 algorithm (will not be NULL)
35 *        algolen: the length of the algo array
36 *           data: arbitrary data pointer that is passed through
37 *
38 *  Except for test cases, this function should compute some cryptographic hash of
39 *  the message, the key, the pubkey, the algorithm description, and data.
40 */
41typedef int (*secp256k1_nonce_function_hardened)(
42    unsigned char *nonce32,
43    const unsigned char *msg,
44    size_t msglen,
45    const unsigned char *key32,
46    const unsigned char *xonly_pk32,
47    const unsigned char *algo,
48    size_t algolen,
49    void *data
50);
51
52/** An implementation of the nonce generation function as defined in Bitcoin
53 *  Improvement Proposal 340 "Schnorr Signatures for secp256k1"
54 *  (https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
55 *
56 *  If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
57 *  auxiliary random data as defined in BIP-340. If the data pointer is NULL,
58 *  the nonce derivation procedure follows BIP-340 by setting the auxiliary
59 *  random data to zero. The algo argument must be non-NULL, otherwise the
60 *  function will fail and return 0. The hash will be tagged with algo.
61 *  Therefore, to create BIP-340 compliant signatures, algo must be set to
62 *  "BIP0340/nonce" and algolen to 13.
63 */
64SECP256K1_API const secp256k1_nonce_function_hardened secp256k1_nonce_function_bip340;
65
66/** Data structure that contains additional arguments for schnorrsig_sign_custom.
67 *
68 *  A schnorrsig_extraparams structure object can be initialized correctly by
69 *  setting it to SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT.
70 *
71 *  Members:
72 *      magic: set to SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC at initialization
73 *             and has no other function than making sure the object is
74 *             initialized.
75 *    noncefp: pointer to a nonce generation function. If NULL,
76 *             secp256k1_nonce_function_bip340 is used
77 *      ndata: pointer to arbitrary data used by the nonce generation function
78 *             (can be NULL). If it is non-NULL and
79 *             secp256k1_nonce_function_bip340 is used, then ndata must be a
80 *             pointer to 32-byte auxiliary randomness as per BIP-340.
81 */
82typedef struct secp256k1_schnorrsig_extraparams {
83    unsigned char magic[4];
84    secp256k1_nonce_function_hardened noncefp;
85    void *ndata;
86} secp256k1_schnorrsig_extraparams;
87
88#define SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC { 0xda, 0x6f, 0xb3, 0x8c }
89#define SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT {\
90    SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC,\
91    NULL,\
92    NULL\
93}
94
95/** Create a Schnorr signature.
96 *
97 *  Does _not_ strictly follow BIP-340 because it does not verify the resulting
98 *  signature. Instead, you can manually use secp256k1_schnorrsig_verify and
99 *  abort if it fails.
100 *
101 *  This function only signs 32-byte messages. If you have messages of a
102 *  different size (or the same size but without a context-specific tag
103 *  prefix), it is recommended to create a 32-byte message hash with
104 *  secp256k1_tagged_sha256 and then sign the hash. Tagged hashing allows
105 *  providing an context-specific tag for domain separation. This prevents
106 *  signatures from being valid in multiple contexts by accident.
107 *
108 *  Returns 1 on success, 0 on failure.
109 *  Args:    ctx: pointer to a context object (not secp256k1_context_static).
110 *  Out:   sig64: pointer to a 64-byte array to store the serialized signature.
111 *  In:    msg32: the 32-byte message being signed.
112 *       keypair: pointer to an initialized keypair.
113 *    aux_rand32: 32 bytes of fresh randomness. While recommended to provide
114 *                this, it is only supplemental to security and can be NULL. A
115 *                NULL argument is treated the same as an all-zero one. See
116 *                BIP-340 "Default Signing" for a full explanation of this
117 *                argument and for guidance if randomness is expensive.
118 */
119SECP256K1_API int secp256k1_schnorrsig_sign32(
120    const secp256k1_context *ctx,
121    unsigned char *sig64,
122    const unsigned char *msg32,
123    const secp256k1_keypair *keypair,
124    const unsigned char *aux_rand32
125) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
126
127/** Create a Schnorr signature with a more flexible API.
128 *
129 *  Same arguments as secp256k1_schnorrsig_sign32 except that it allows signing
130 *  variable length messages and accepts a pointer to an extraparams object that
131 *  allows customizing signing by passing additional arguments.
132 *
133 *  Equivalent to secp256k1_schnorrsig_sign32(..., aux_rand32) if msglen is 32
134 *  and extraparams is initialized as follows:
135 *  ```
136 *  secp256k1_schnorrsig_extraparams extraparams = SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT;
137 *  extraparams.ndata = (unsigned char*)aux_rand32;
138 *  ```
139 *
140 *  Returns 1 on success, 0 on failure.
141 *  Args:   ctx: pointer to a context object (not secp256k1_context_static).
142 *  Out:  sig64: pointer to a 64-byte array to store the serialized signature.
143 *  In:     msg: the message being signed. Can only be NULL if msglen is 0.
144 *       msglen: length of the message.
145 *      keypair: pointer to an initialized keypair.
146 *  extraparams: pointer to an extraparams object (can be NULL).
147 */
148SECP256K1_API int secp256k1_schnorrsig_sign_custom(
149    const secp256k1_context *ctx,
150    unsigned char *sig64,
151    const unsigned char *msg,
152    size_t msglen,
153    const secp256k1_keypair *keypair,
154    secp256k1_schnorrsig_extraparams *extraparams
155) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(5);
156
157/** Verify a Schnorr signature.
158 *
159 *  Returns: 1: correct signature
160 *           0: incorrect signature
161 *  Args:    ctx: pointer to a context object.
162 *  In:    sig64: pointer to the 64-byte signature to verify.
163 *           msg: the message being verified. Can only be NULL if msglen is 0.
164 *        msglen: length of the message
165 *        pubkey: pointer to an x-only public key to verify with
166 */
167SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_schnorrsig_verify(
168    const secp256k1_context *ctx,
169    const unsigned char *sig64,
170    const unsigned char *msg,
171    size_t msglen,
172    const secp256k1_xonly_pubkey *pubkey
173) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(5);
174
175#ifdef __cplusplus
176}
177#endif
178
179#endif /* SECP256K1_SCHNORRSIG_H */
180

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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