mirror of
https://github.com/nbd-wtf/go-nostr.git
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vendor libsecp256k1 so it doesn't depend on a shared library.
This commit is contained in:
fiatjaf
899
libsecp256k1/include/secp256k1.h
Normal file
899
libsecp256k1/include/secp256k1.h
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@@ -0,0 +1,899 @@
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#ifndef SECP256K1_H
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#define SECP256K1_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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#include <stddef.h>
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/** Unless explicitly stated all pointer arguments must not be NULL.
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*
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* The following rules specify the order of arguments in API calls:
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*
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* 1. Context pointers go first, followed by output arguments, combined
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* output/input arguments, and finally input-only arguments.
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* 2. Array lengths always immediately follow the argument whose length
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* they describe, even if this violates rule 1.
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* 3. Within the OUT/OUTIN/IN groups, pointers to data that is typically generated
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* later go first. This means: signatures, public nonces, secret nonces,
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* messages, public keys, secret keys, tweaks.
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* 4. Arguments that are not data pointers go last, from more complex to less
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* complex: function pointers, algorithm names, messages, void pointers,
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* counts, flags, booleans.
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* 5. Opaque data pointers follow the function pointer they are to be passed to.
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*/
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/** Opaque data structure that holds context information
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*
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* The primary purpose of context objects is to store randomization data for
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* enhanced protection against side-channel leakage. This protection is only
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* effective if the context is randomized after its creation. See
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* secp256k1_context_create for creation of contexts and
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* secp256k1_context_randomize for randomization.
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*
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* A secondary purpose of context objects is to store pointers to callback
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* functions that the library will call when certain error states arise. See
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* secp256k1_context_set_error_callback as well as
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* secp256k1_context_set_illegal_callback for details. Future library versions
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* may use context objects for additional purposes.
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*
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* A constructed context can safely be used from multiple threads
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* simultaneously, but API calls that take a non-const pointer to a context
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* need exclusive access to it. In particular this is the case for
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* secp256k1_context_destroy, secp256k1_context_preallocated_destroy,
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* and secp256k1_context_randomize.
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*
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* Regarding randomization, either do it once at creation time (in which case
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* you do not need any locking for the other calls), or use a read-write lock.
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*/
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typedef struct secp256k1_context_struct secp256k1_context;
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/** Opaque data structure that holds a parsed and valid public key.
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*
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* The exact representation of data inside is implementation defined and not
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* guaranteed to be portable between different platforms or versions. It is
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* however guaranteed to be 64 bytes in size, and can be safely copied/moved.
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* If you need to convert to a format suitable for storage or transmission,
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* use secp256k1_ec_pubkey_serialize and secp256k1_ec_pubkey_parse. To
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* compare keys, use secp256k1_ec_pubkey_cmp.
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*/
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typedef struct secp256k1_pubkey {
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unsigned char data[64];
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} secp256k1_pubkey;
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/** Opaque data structure that holds a parsed ECDSA signature.
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*
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* The exact representation of data inside is implementation defined and not
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* guaranteed to be portable between different platforms or versions. It is
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* however guaranteed to be 64 bytes in size, and can be safely copied/moved.
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* If you need to convert to a format suitable for storage, transmission, or
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* comparison, use the secp256k1_ecdsa_signature_serialize_* and
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* secp256k1_ecdsa_signature_parse_* functions.
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*/
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typedef struct secp256k1_ecdsa_signature {
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unsigned char data[64];
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} secp256k1_ecdsa_signature;
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/** A pointer to a function to deterministically generate a nonce.
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*
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* Returns: 1 if a nonce was successfully generated. 0 will cause signing to fail.
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* Out: nonce32: pointer to a 32-byte array to be filled by the function.
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* In: msg32: the 32-byte message hash being verified (will not be NULL)
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* key32: pointer to a 32-byte secret key (will not be NULL)
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* algo16: pointer to a 16-byte array describing the signature
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* algorithm (will be NULL for ECDSA for compatibility).
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* data: Arbitrary data pointer that is passed through.
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* attempt: how many iterations we have tried to find a nonce.
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* This will almost always be 0, but different attempt values
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* are required to result in a different nonce.
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*
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* Except for test cases, this function should compute some cryptographic hash of
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* the message, the algorithm, the key and the attempt.
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*/
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typedef int (*secp256k1_nonce_function)(
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unsigned char *nonce32,
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const unsigned char *msg32,
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const unsigned char *key32,
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const unsigned char *algo16,
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void *data,
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unsigned int attempt
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);
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# if !defined(SECP256K1_GNUC_PREREQ)
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# if defined(__GNUC__)&&defined(__GNUC_MINOR__)
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# define SECP256K1_GNUC_PREREQ(_maj,_min) \
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((__GNUC__<<16)+__GNUC_MINOR__>=((_maj)<<16)+(_min))
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# else
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# define SECP256K1_GNUC_PREREQ(_maj,_min) 0
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# endif
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# endif
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/* When this header is used at build-time the SECP256K1_BUILD define needs to be set
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* to correctly setup export attributes and nullness checks. This is normally done
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* by secp256k1.c but to guard against this header being included before secp256k1.c
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* has had a chance to set the define (e.g. via test harnesses that just includes
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* secp256k1.c) we set SECP256K1_NO_BUILD when this header is processed without the
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* BUILD define so this condition can be caught.
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*/
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#ifndef SECP256K1_BUILD
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# define SECP256K1_NO_BUILD
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#endif
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/* Symbol visibility. */
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#if defined(_WIN32)
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/* GCC for Windows (e.g., MinGW) accepts the __declspec syntax
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* for MSVC compatibility. A __declspec declaration implies (but is not
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* exactly equivalent to) __attribute__ ((visibility("default"))), and so we
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* actually want __declspec even on GCC, see "Microsoft Windows Function
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* Attributes" in the GCC manual and the recommendations in
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* https://gcc.gnu.org/wiki/Visibility. */
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# if defined(SECP256K1_BUILD)
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# if defined(DLL_EXPORT) || defined(SECP256K1_DLL_EXPORT)
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/* Building libsecp256k1 as a DLL.
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* 1. If using Libtool, it defines DLL_EXPORT automatically.
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* 2. In other cases, SECP256K1_DLL_EXPORT must be defined. */
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# define SECP256K1_API extern __declspec (dllexport)
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# else
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/* Building libsecp256k1 as a static library on Windows.
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* No declspec is needed, and so we would want the non-Windows-specific
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* logic below take care of this case. However, this may result in setting
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* __attribute__ ((visibility("default"))), which is supposed to be a noop
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* on Windows but may trigger warnings when compiling with -flto due to a
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* bug in GCC, see
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* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116478 . */
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# define SECP256K1_API extern
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# endif
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/* The user must define SECP256K1_STATIC when consuming libsecp256k1 as a static
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* library on Windows. */
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# elif !defined(SECP256K1_STATIC)
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/* Consuming libsecp256k1 as a DLL. */
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# define SECP256K1_API extern __declspec (dllimport)
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# endif
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#endif
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#ifndef SECP256K1_API
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/* All cases not captured by the Windows-specific logic. */
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# if defined(__GNUC__) && (__GNUC__ >= 4) && defined(SECP256K1_BUILD)
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/* Building libsecp256k1 using GCC or compatible. */
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# define SECP256K1_API extern __attribute__ ((visibility ("default")))
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# else
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/* Fall back to standard C's extern. */
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# define SECP256K1_API extern
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# endif
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#endif
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/* Warning attributes
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* NONNULL is not used if SECP256K1_BUILD is set to avoid the compiler optimizing out
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* some paranoid null checks. */
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# if defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
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# define SECP256K1_WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__))
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# else
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# define SECP256K1_WARN_UNUSED_RESULT
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# endif
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# if !defined(SECP256K1_BUILD) && defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
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# define SECP256K1_ARG_NONNULL(_x) __attribute__ ((__nonnull__(_x)))
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# else
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# define SECP256K1_ARG_NONNULL(_x)
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# endif
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/* Attribute for marking functions, types, and variables as deprecated */
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#if !defined(SECP256K1_BUILD) && defined(__has_attribute)
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# if __has_attribute(__deprecated__)
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# define SECP256K1_DEPRECATED(_msg) __attribute__ ((__deprecated__(_msg)))
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# else
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# define SECP256K1_DEPRECATED(_msg)
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# endif
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#else
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# define SECP256K1_DEPRECATED(_msg)
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#endif
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/* All flags' lower 8 bits indicate what they're for. Do not use directly. */
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#define SECP256K1_FLAGS_TYPE_MASK ((1 << 8) - 1)
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#define SECP256K1_FLAGS_TYPE_CONTEXT (1 << 0)
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#define SECP256K1_FLAGS_TYPE_COMPRESSION (1 << 1)
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/* The higher bits contain the actual data. Do not use directly. */
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#define SECP256K1_FLAGS_BIT_CONTEXT_VERIFY (1 << 8)
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#define SECP256K1_FLAGS_BIT_CONTEXT_SIGN (1 << 9)
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#define SECP256K1_FLAGS_BIT_CONTEXT_DECLASSIFY (1 << 10)
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#define SECP256K1_FLAGS_BIT_COMPRESSION (1 << 8)
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/** Context flags to pass to secp256k1_context_create, secp256k1_context_preallocated_size, and
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* secp256k1_context_preallocated_create. */
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#define SECP256K1_CONTEXT_NONE (SECP256K1_FLAGS_TYPE_CONTEXT)
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/** Deprecated context flags. These flags are treated equivalent to SECP256K1_CONTEXT_NONE. */
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#define SECP256K1_CONTEXT_VERIFY (SECP256K1_FLAGS_TYPE_CONTEXT | SECP256K1_FLAGS_BIT_CONTEXT_VERIFY)
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#define SECP256K1_CONTEXT_SIGN (SECP256K1_FLAGS_TYPE_CONTEXT | SECP256K1_FLAGS_BIT_CONTEXT_SIGN)
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/* Testing flag. Do not use. */
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#define SECP256K1_CONTEXT_DECLASSIFY (SECP256K1_FLAGS_TYPE_CONTEXT | SECP256K1_FLAGS_BIT_CONTEXT_DECLASSIFY)
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/** Flag to pass to secp256k1_ec_pubkey_serialize. */
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#define SECP256K1_EC_COMPRESSED (SECP256K1_FLAGS_TYPE_COMPRESSION | SECP256K1_FLAGS_BIT_COMPRESSION)
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#define SECP256K1_EC_UNCOMPRESSED (SECP256K1_FLAGS_TYPE_COMPRESSION)
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/** Prefix byte used to tag various encoded curvepoints for specific purposes */
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#define SECP256K1_TAG_PUBKEY_EVEN 0x02
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#define SECP256K1_TAG_PUBKEY_ODD 0x03
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#define SECP256K1_TAG_PUBKEY_UNCOMPRESSED 0x04
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#define SECP256K1_TAG_PUBKEY_HYBRID_EVEN 0x06
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#define SECP256K1_TAG_PUBKEY_HYBRID_ODD 0x07
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/** A built-in constant secp256k1 context object with static storage duration, to be
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* used in conjunction with secp256k1_selftest.
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*
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* This context object offers *only limited functionality* , i.e., it cannot be used
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* for API functions that perform computations involving secret keys, e.g., signing
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* and public key generation. If this restriction applies to a specific API function,
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* it is mentioned in its documentation. See secp256k1_context_create if you need a
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* full context object that supports all functionality offered by the library.
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*
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* It is highly recommended to call secp256k1_selftest before using this context.
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*/
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SECP256K1_API const secp256k1_context *secp256k1_context_static;
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/** Deprecated alias for secp256k1_context_static. */
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SECP256K1_API const secp256k1_context *secp256k1_context_no_precomp
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SECP256K1_DEPRECATED("Use secp256k1_context_static instead");
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/** Perform basic self tests (to be used in conjunction with secp256k1_context_static)
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*
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* This function performs self tests that detect some serious usage errors and
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* similar conditions, e.g., when the library is compiled for the wrong endianness.
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* This is a last resort measure to be used in production. The performed tests are
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* very rudimentary and are not intended as a replacement for running the test
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* binaries.
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*
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* It is highly recommended to call this before using secp256k1_context_static.
|
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* It is not necessary to call this function before using a context created with
|
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* secp256k1_context_create (or secp256k1_context_preallocated_create), which will
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* take care of performing the self tests.
|
||||
*
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* If the tests fail, this function will call the default error handler to abort the
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* program (see secp256k1_context_set_error_callback).
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*/
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SECP256K1_API void secp256k1_selftest(void);
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/** Create a secp256k1 context object (in dynamically allocated memory).
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*
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* This function uses malloc to allocate memory. It is guaranteed that malloc is
|
||||
* called at most once for every call of this function. If you need to avoid dynamic
|
||||
* memory allocation entirely, see secp256k1_context_static and the functions in
|
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* secp256k1_preallocated.h.
|
||||
*
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||||
* Returns: pointer to a newly created context object.
|
||||
* In: flags: Always set to SECP256K1_CONTEXT_NONE (see below).
|
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*
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* The only valid non-deprecated flag in recent library versions is
|
||||
* SECP256K1_CONTEXT_NONE, which will create a context sufficient for all functionality
|
||||
* offered by the library. All other (deprecated) flags will be treated as equivalent
|
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* to the SECP256K1_CONTEXT_NONE flag. Though the flags parameter primarily exists for
|
||||
* historical reasons, future versions of the library may introduce new flags.
|
||||
*
|
||||
* If the context is intended to be used for API functions that perform computations
|
||||
* involving secret keys, e.g., signing and public key generation, then it is highly
|
||||
* recommended to call secp256k1_context_randomize on the context before calling
|
||||
* those API functions. This will provide enhanced protection against side-channel
|
||||
* leakage, see secp256k1_context_randomize for details.
|
||||
*
|
||||
* Do not create a new context object for each operation, as construction and
|
||||
* randomization can take non-negligible time.
|
||||
*/
|
||||
SECP256K1_API secp256k1_context *secp256k1_context_create(
|
||||
unsigned int flags
|
||||
) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Copy a secp256k1 context object (into dynamically allocated memory).
|
||||
*
|
||||
* This function uses malloc to allocate memory. It is guaranteed that malloc is
|
||||
* called at most once for every call of this function. If you need to avoid dynamic
|
||||
* memory allocation entirely, see the functions in secp256k1_preallocated.h.
|
||||
*
|
||||
* Cloning secp256k1_context_static is not possible, and should not be emulated by
|
||||
* the caller (e.g., using memcpy). Create a new context instead.
|
||||
*
|
||||
* Returns: pointer to a newly created context object.
|
||||
* Args: ctx: pointer to a context to copy (not secp256k1_context_static).
|
||||
*/
|
||||
SECP256K1_API secp256k1_context *secp256k1_context_clone(
|
||||
const secp256k1_context *ctx
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Destroy a secp256k1 context object (created in dynamically allocated memory).
|
||||
*
|
||||
* The context pointer may not be used afterwards.
|
||||
*
|
||||
* The context to destroy must have been created using secp256k1_context_create
|
||||
* or secp256k1_context_clone. If the context has instead been created using
|
||||
* secp256k1_context_preallocated_create or secp256k1_context_preallocated_clone, the
|
||||
* behaviour is undefined. In that case, secp256k1_context_preallocated_destroy must
|
||||
* be used instead.
|
||||
*
|
||||
* Args: ctx: pointer to a context to destroy, constructed using
|
||||
* secp256k1_context_create or secp256k1_context_clone
|
||||
* (i.e., not secp256k1_context_static).
|
||||
*/
|
||||
SECP256K1_API void secp256k1_context_destroy(
|
||||
secp256k1_context *ctx
|
||||
) SECP256K1_ARG_NONNULL(1);
|
||||
|
||||
/** Set a callback function to be called when an illegal argument is passed to
|
||||
* an API call. It will only trigger for violations that are mentioned
|
||||
* explicitly in the header.
|
||||
*
|
||||
* The philosophy is that these shouldn't be dealt with through a
|
||||
* specific return value, as calling code should not have branches to deal with
|
||||
* the case that this code itself is broken.
|
||||
*
|
||||
* On the other hand, during debug stage, one would want to be informed about
|
||||
* such mistakes, and the default (crashing) may be inadvisable.
|
||||
* When this callback is triggered, the API function called is guaranteed not
|
||||
* to cause a crash, though its return value and output arguments are
|
||||
* undefined.
|
||||
*
|
||||
* When this function has not been called (or called with fn==NULL), then the
|
||||
* default handler will be used. The library provides a default handler which
|
||||
* writes the message to stderr and calls abort. This default handler can be
|
||||
* replaced at link time if the preprocessor macro
|
||||
* USE_EXTERNAL_DEFAULT_CALLBACKS is defined, which is the case if the build
|
||||
* has been configured with --enable-external-default-callbacks. Then the
|
||||
* following two symbols must be provided to link against:
|
||||
* - void secp256k1_default_illegal_callback_fn(const char *message, void *data);
|
||||
* - void secp256k1_default_error_callback_fn(const char *message, void *data);
|
||||
* The library can call these default handlers even before a proper callback data
|
||||
* pointer could have been set using secp256k1_context_set_illegal_callback or
|
||||
* secp256k1_context_set_error_callback, e.g., when the creation of a context
|
||||
* fails. In this case, the corresponding default handler will be called with
|
||||
* the data pointer argument set to NULL.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: fun: pointer to a function to call when an illegal argument is
|
||||
* passed to the API, taking a message and an opaque pointer.
|
||||
* (NULL restores the default handler.)
|
||||
* data: the opaque pointer to pass to fun above, must be NULL for the default handler.
|
||||
*
|
||||
* See also secp256k1_context_set_error_callback.
|
||||
*/
|
||||
SECP256K1_API void secp256k1_context_set_illegal_callback(
|
||||
secp256k1_context *ctx,
|
||||
void (*fun)(const char *message, void *data),
|
||||
const void *data
|
||||
) SECP256K1_ARG_NONNULL(1);
|
||||
|
||||
/** Set a callback function to be called when an internal consistency check
|
||||
* fails.
|
||||
*
|
||||
* The default callback writes an error message to stderr and calls abort
|
||||
* to abort the program.
|
||||
*
|
||||
* This can only trigger in case of a hardware failure, miscompilation,
|
||||
* memory corruption, serious bug in the library, or other error would can
|
||||
* otherwise result in undefined behaviour. It will not trigger due to mere
|
||||
* incorrect usage of the API (see secp256k1_context_set_illegal_callback
|
||||
* for that). After this callback returns, anything may happen, including
|
||||
* crashing.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: fun: pointer to a function to call when an internal error occurs,
|
||||
* taking a message and an opaque pointer (NULL restores the
|
||||
* default handler, see secp256k1_context_set_illegal_callback
|
||||
* for details).
|
||||
* data: the opaque pointer to pass to fun above, must be NULL for the default handler.
|
||||
*
|
||||
* See also secp256k1_context_set_illegal_callback.
|
||||
*/
|
||||
SECP256K1_API void secp256k1_context_set_error_callback(
|
||||
secp256k1_context *ctx,
|
||||
void (*fun)(const char *message, void *data),
|
||||
const void *data
|
||||
) SECP256K1_ARG_NONNULL(1);
|
||||
|
||||
/** Parse a variable-length public key into the pubkey object.
|
||||
*
|
||||
* Returns: 1 if the public key was fully valid.
|
||||
* 0 if the public key could not be parsed or is invalid.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to a
|
||||
* parsed version of input. If not, its value is undefined.
|
||||
* In: input: pointer to a serialized public key
|
||||
* inputlen: length of the array pointed to by input
|
||||
*
|
||||
* This function supports parsing compressed (33 bytes, header byte 0x02 or
|
||||
* 0x03), uncompressed (65 bytes, header byte 0x04), or hybrid (65 bytes, header
|
||||
* byte 0x06 or 0x07) format public keys.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_parse(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const unsigned char *input,
|
||||
size_t inputlen
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Serialize a pubkey object into a serialized byte sequence.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output: pointer to a 65-byte (if compressed==0) or 33-byte (if
|
||||
* compressed==1) byte array to place the serialized key
|
||||
* in.
|
||||
* In/Out: outputlen: pointer to an integer which is initially set to the
|
||||
* size of output, and is overwritten with the written
|
||||
* size.
|
||||
* In: pubkey: pointer to a secp256k1_pubkey containing an
|
||||
* initialized public key.
|
||||
* flags: SECP256K1_EC_COMPRESSED if serialization should be in
|
||||
* compressed format, otherwise SECP256K1_EC_UNCOMPRESSED.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ec_pubkey_serialize(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output,
|
||||
size_t *outputlen,
|
||||
const secp256k1_pubkey *pubkey,
|
||||
unsigned int flags
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Compare two public keys using lexicographic (of compressed serialization) order
|
||||
*
|
||||
* Returns: <0 if the first public key is less than the second
|
||||
* >0 if the first public key is greater than the second
|
||||
* 0 if the two public keys are equal
|
||||
* Args: ctx: pointer to a context object
|
||||
* In: pubkey1: first public key to compare
|
||||
* pubkey2: second public key to compare
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_cmp(
|
||||
const secp256k1_context *ctx,
|
||||
const secp256k1_pubkey *pubkey1,
|
||||
const secp256k1_pubkey *pubkey2
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Sort public keys using lexicographic (of compressed serialization) order
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid. 1 otherwise.
|
||||
*
|
||||
* Args: ctx: pointer to a context object
|
||||
* In: pubkeys: array of pointers to pubkeys to sort
|
||||
* n_pubkeys: number of elements in the pubkeys array
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ec_pubkey_sort(
|
||||
const secp256k1_context *ctx,
|
||||
const secp256k1_pubkey **pubkeys,
|
||||
size_t n_pubkeys
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
|
||||
|
||||
/** Parse an ECDSA signature in compact (64 bytes) format.
|
||||
*
|
||||
* Returns: 1 when the signature could be parsed, 0 otherwise.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: sig: pointer to a signature object
|
||||
* In: input64: pointer to the 64-byte array to parse
|
||||
*
|
||||
* The signature must consist of a 32-byte big endian R value, followed by a
|
||||
* 32-byte big endian S value. If R or S fall outside of [0..order-1], the
|
||||
* encoding is invalid. R and S with value 0 are allowed in the encoding.
|
||||
*
|
||||
* After the call, sig will always be initialized. If parsing failed or R or
|
||||
* S are zero, the resulting sig value is guaranteed to fail verification for
|
||||
* any message and public key.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_signature_parse_compact(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_signature *sig,
|
||||
const unsigned char *input64
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Parse a DER ECDSA signature.
|
||||
*
|
||||
* Returns: 1 when the signature could be parsed, 0 otherwise.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: sig: pointer to a signature object
|
||||
* In: input: pointer to the signature to be parsed
|
||||
* inputlen: the length of the array pointed to be input
|
||||
*
|
||||
* This function will accept any valid DER encoded signature, even if the
|
||||
* encoded numbers are out of range.
|
||||
*
|
||||
* After the call, sig will always be initialized. If parsing failed or the
|
||||
* encoded numbers are out of range, signature verification with it is
|
||||
* guaranteed to fail for every message and public key.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_signature_parse_der(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_signature *sig,
|
||||
const unsigned char *input,
|
||||
size_t inputlen
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Serialize an ECDSA signature in DER format.
|
||||
*
|
||||
* Returns: 1 if enough space was available to serialize, 0 otherwise
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: output: pointer to an array to store the DER serialization
|
||||
* In/Out: outputlen: pointer to a length integer. Initially, this integer
|
||||
* should be set to the length of output. After the call
|
||||
* it will be set to the length of the serialization (even
|
||||
* if 0 was returned).
|
||||
* In: sig: pointer to an initialized signature object
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_signature_serialize_der(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output,
|
||||
size_t *outputlen,
|
||||
const secp256k1_ecdsa_signature *sig
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Serialize an ECDSA signature in compact (64 byte) format.
|
||||
*
|
||||
* Returns: 1
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: output64: pointer to a 64-byte array to store the compact serialization
|
||||
* In: sig: pointer to an initialized signature object
|
||||
*
|
||||
* See secp256k1_ecdsa_signature_parse_compact for details about the encoding.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_signature_serialize_compact(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output64,
|
||||
const secp256k1_ecdsa_signature *sig
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Verify an ECDSA signature.
|
||||
*
|
||||
* Returns: 1: correct signature
|
||||
* 0: incorrect or unparseable signature
|
||||
* Args: ctx: pointer to a context object
|
||||
* In: sig: the signature being verified.
|
||||
* msghash32: the 32-byte message hash being verified.
|
||||
* The verifier must make sure to apply a cryptographic
|
||||
* hash function to the message by itself and not accept an
|
||||
* msghash32 value directly. Otherwise, it would be easy to
|
||||
* create a "valid" signature without knowledge of the
|
||||
* secret key. See also
|
||||
* https://bitcoin.stackexchange.com/a/81116/35586 for more
|
||||
* background on this topic.
|
||||
* pubkey: pointer to an initialized public key to verify with.
|
||||
*
|
||||
* To avoid accepting malleable signatures, only ECDSA signatures in lower-S
|
||||
* form are accepted.
|
||||
*
|
||||
* If you need to accept ECDSA signatures from sources that do not obey this
|
||||
* rule, apply secp256k1_ecdsa_signature_normalize to the signature prior to
|
||||
* verification, but be aware that doing so results in malleable signatures.
|
||||
*
|
||||
* For details, see the comments for that function.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_verify(
|
||||
const secp256k1_context *ctx,
|
||||
const secp256k1_ecdsa_signature *sig,
|
||||
const unsigned char *msghash32,
|
||||
const secp256k1_pubkey *pubkey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Convert a signature to a normalized lower-S form.
|
||||
*
|
||||
* Returns: 1 if sigin was not normalized, 0 if it already was.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: sigout: pointer to a signature to fill with the normalized form,
|
||||
* or copy if the input was already normalized. (can be NULL if
|
||||
* you're only interested in whether the input was already
|
||||
* normalized).
|
||||
* In: sigin: pointer to a signature to check/normalize (can be identical to sigout)
|
||||
*
|
||||
* With ECDSA a third-party can forge a second distinct signature of the same
|
||||
* message, given a single initial signature, but without knowing the key. This
|
||||
* is done by negating the S value modulo the order of the curve, 'flipping'
|
||||
* the sign of the random point R which is not included in the signature.
|
||||
*
|
||||
* Forgery of the same message isn't universally problematic, but in systems
|
||||
* where message malleability or uniqueness of signatures is important this can
|
||||
* cause issues. This forgery can be blocked by all verifiers forcing signers
|
||||
* to use a normalized form.
|
||||
*
|
||||
* The lower-S form reduces the size of signatures slightly on average when
|
||||
* variable length encodings (such as DER) are used and is cheap to verify,
|
||||
* making it a good choice. Security of always using lower-S is assured because
|
||||
* anyone can trivially modify a signature after the fact to enforce this
|
||||
* property anyway.
|
||||
*
|
||||
* The lower S value is always between 0x1 and
|
||||
* 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
|
||||
* inclusive.
|
||||
*
|
||||
* No other forms of ECDSA malleability are known and none seem likely, but
|
||||
* there is no formal proof that ECDSA, even with this additional restriction,
|
||||
* is free of other malleability. Commonly used serialization schemes will also
|
||||
* accept various non-unique encodings, so care should be taken when this
|
||||
* property is required for an application.
|
||||
*
|
||||
* The secp256k1_ecdsa_sign function will by default create signatures in the
|
||||
* lower-S form, and secp256k1_ecdsa_verify will not accept others. In case
|
||||
* signatures come from a system that cannot enforce this property,
|
||||
* secp256k1_ecdsa_signature_normalize must be called before verification.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_signature_normalize(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_signature *sigout,
|
||||
const secp256k1_ecdsa_signature *sigin
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** An implementation of RFC6979 (using HMAC-SHA256) as nonce generation function.
|
||||
* If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
|
||||
* extra entropy.
|
||||
*/
|
||||
SECP256K1_API const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
|
||||
|
||||
/** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
|
||||
SECP256K1_API const secp256k1_nonce_function secp256k1_nonce_function_default;
|
||||
|
||||
/** Create an ECDSA signature.
|
||||
*
|
||||
* Returns: 1: signature created
|
||||
* 0: the nonce generation function failed, or the secret key was invalid.
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: sig: pointer to an array where the signature will be placed.
|
||||
* In: msghash32: the 32-byte message hash being signed.
|
||||
* seckey: pointer to a 32-byte secret key.
|
||||
* noncefp: pointer to a nonce generation function. If NULL,
|
||||
* secp256k1_nonce_function_default is used.
|
||||
* ndata: pointer to arbitrary data used by the nonce generation function
|
||||
* (can be NULL). If it is non-NULL and
|
||||
* secp256k1_nonce_function_default is used, then ndata must be a
|
||||
* pointer to 32-bytes of additional data.
|
||||
*
|
||||
* The created signature is always in lower-S form. See
|
||||
* secp256k1_ecdsa_signature_normalize for more details.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_sign(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_signature *sig,
|
||||
const unsigned char *msghash32,
|
||||
const unsigned char *seckey,
|
||||
secp256k1_nonce_function noncefp,
|
||||
const void *ndata
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Verify an elliptic curve secret key.
|
||||
*
|
||||
* A secret key is valid if it is not 0 and less than the secp256k1 curve order
|
||||
* when interpreted as an integer (most significant byte first). The
|
||||
* probability of choosing a 32-byte string uniformly at random which is an
|
||||
* invalid secret key is negligible. However, if it does happen it should
|
||||
* be assumed that the randomness source is severely broken and there should
|
||||
* be no retry.
|
||||
*
|
||||
* Returns: 1: secret key is valid
|
||||
* 0: secret key is invalid
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: seckey: pointer to a 32-byte secret key.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(
|
||||
const secp256k1_context *ctx,
|
||||
const unsigned char *seckey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
|
||||
|
||||
/** Compute the public key for a secret key.
|
||||
*
|
||||
* Returns: 1: secret was valid, public key stores.
|
||||
* 0: secret was invalid, try again.
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: pubkey: pointer to the created public key.
|
||||
* In: seckey: pointer to a 32-byte secret key.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const unsigned char *seckey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Negates a secret key in place.
|
||||
*
|
||||
* Returns: 0 if the given secret key is invalid according to
|
||||
* secp256k1_ec_seckey_verify. 1 otherwise
|
||||
* Args: ctx: pointer to a context object
|
||||
* In/Out: seckey: pointer to the 32-byte secret key to be negated. If the
|
||||
* secret key is invalid according to
|
||||
* secp256k1_ec_seckey_verify, this function returns 0 and
|
||||
* seckey will be set to some unspecified value.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_negate(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
|
||||
|
||||
/** Same as secp256k1_ec_seckey_negate, but DEPRECATED. Will be removed in
|
||||
* future versions. */
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_negate(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2)
|
||||
SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_negate instead");
|
||||
|
||||
/** Negates a public key in place.
|
||||
*
|
||||
* Returns: 1 always
|
||||
* Args: ctx: pointer to a context object
|
||||
* In/Out: pubkey: pointer to the public key to be negated.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_negate(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
|
||||
|
||||
/** Tweak a secret key by adding tweak to it.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid or the resulting secret key would be
|
||||
* invalid (only when the tweak is the negation of the secret key). 1
|
||||
* otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In/Out: seckey: pointer to a 32-byte secret key. If the secret key is
|
||||
* invalid according to secp256k1_ec_seckey_verify, this
|
||||
* function returns 0. seckey will be set to some unspecified
|
||||
* value if this function returns 0.
|
||||
* In: tweak32: pointer to a 32-byte tweak, which must be valid according to
|
||||
* secp256k1_ec_seckey_verify or 32 zero bytes. For uniformly
|
||||
* random 32-byte tweaks, the chance of being invalid is
|
||||
* negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_tweak_add(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Same as secp256k1_ec_seckey_tweak_add, but DEPRECATED. Will be removed in
|
||||
* future versions. */
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3)
|
||||
SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_tweak_add instead");
|
||||
|
||||
/** Tweak a public key by adding tweak times the generator to it.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid or the resulting public key would be
|
||||
* invalid (only when the tweak is the negation of the corresponding
|
||||
* secret key). 1 otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In/Out: pubkey: pointer to a public key object. pubkey will be set to an
|
||||
* invalid value if this function returns 0.
|
||||
* In: tweak32: pointer to a 32-byte tweak, which must be valid according to
|
||||
* secp256k1_ec_seckey_verify or 32 zero bytes. For uniformly
|
||||
* random 32-byte tweaks, the chance of being invalid is
|
||||
* negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Tweak a secret key by multiplying it by a tweak.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid. 1 otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In/Out: seckey: pointer to a 32-byte secret key. If the secret key is
|
||||
* invalid according to secp256k1_ec_seckey_verify, this
|
||||
* function returns 0. seckey will be set to some unspecified
|
||||
* value if this function returns 0.
|
||||
* In: tweak32: pointer to a 32-byte tweak. If the tweak is invalid according to
|
||||
* secp256k1_ec_seckey_verify, this function returns 0. For
|
||||
* uniformly random 32-byte arrays the chance of being invalid
|
||||
* is negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_tweak_mul(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Same as secp256k1_ec_seckey_tweak_mul, but DEPRECATED. Will be removed in
|
||||
* future versions. */
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3)
|
||||
SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_tweak_mul instead");
|
||||
|
||||
/** Tweak a public key by multiplying it by a tweak value.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid. 1 otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In/Out: pubkey: pointer to a public key object. pubkey will be set to an
|
||||
* invalid value if this function returns 0.
|
||||
* In: tweak32: pointer to a 32-byte tweak. If the tweak is invalid according to
|
||||
* secp256k1_ec_seckey_verify, this function returns 0. For
|
||||
* uniformly random 32-byte arrays the chance of being invalid
|
||||
* is negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Randomizes the context to provide enhanced protection against side-channel leakage.
|
||||
*
|
||||
* Returns: 1: randomization successful
|
||||
* 0: error
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* In: seed32: pointer to a 32-byte random seed (NULL resets to initial state).
|
||||
*
|
||||
* While secp256k1 code is written and tested to be constant-time no matter what
|
||||
* secret values are, it is possible that a compiler may output code which is not,
|
||||
* and also that the CPU may not emit the same radio frequencies or draw the same
|
||||
* amount of power for all values. Randomization of the context shields against
|
||||
* side-channel observations which aim to exploit secret-dependent behaviour in
|
||||
* certain computations which involve secret keys.
|
||||
*
|
||||
* It is highly recommended to call this function on contexts returned from
|
||||
* secp256k1_context_create or secp256k1_context_clone (or from the corresponding
|
||||
* functions in secp256k1_preallocated.h) before using these contexts to call API
|
||||
* functions that perform computations involving secret keys, e.g., signing and
|
||||
* public key generation. It is possible to call this function more than once on
|
||||
* the same context, and doing so before every few computations involving secret
|
||||
* keys is recommended as a defense-in-depth measure. Randomization of the static
|
||||
* context secp256k1_context_static is not supported.
|
||||
*
|
||||
* Currently, the random seed is mainly used for blinding multiplications of a
|
||||
* secret scalar with the elliptic curve base point. Multiplications of this
|
||||
* kind are performed by exactly those API functions which are documented to
|
||||
* require a context that is not secp256k1_context_static. As a rule of thumb,
|
||||
* these are all functions which take a secret key (or a keypair) as an input.
|
||||
* A notable exception to that rule is the ECDH module, which relies on a different
|
||||
* kind of elliptic curve point multiplication and thus does not benefit from
|
||||
* enhanced protection against side-channel leakage currently.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_context_randomize(
|
||||
secp256k1_context *ctx,
|
||||
const unsigned char *seed32
|
||||
) SECP256K1_ARG_NONNULL(1);
|
||||
|
||||
/** Add a number of public keys together.
|
||||
*
|
||||
* Returns: 1: the sum of the public keys is valid.
|
||||
* 0: the sum of the public keys is not valid.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: out: pointer to a public key object for placing the resulting public key.
|
||||
* In: ins: pointer to array of pointers to public keys.
|
||||
* n: the number of public keys to add together (must be at least 1).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_combine(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *out,
|
||||
const secp256k1_pubkey * const *ins,
|
||||
size_t n
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Compute a tagged hash as defined in BIP-340.
|
||||
*
|
||||
* This is useful for creating a message hash and achieving domain separation
|
||||
* through an application-specific tag. This function returns
|
||||
* SHA256(SHA256(tag)||SHA256(tag)||msg). Therefore, tagged hash
|
||||
* implementations optimized for a specific tag can precompute the SHA256 state
|
||||
* after hashing the tag hashes.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: hash32: pointer to a 32-byte array to store the resulting hash
|
||||
* In: tag: pointer to an array containing the tag
|
||||
* taglen: length of the tag array
|
||||
* msg: pointer to an array containing the message
|
||||
* msglen: length of the message array
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_tagged_sha256(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *hash32,
|
||||
const unsigned char *tag,
|
||||
size_t taglen,
|
||||
const unsigned char *msg,
|
||||
size_t msglen
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(5);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_H */
|
||||
63
libsecp256k1/include/secp256k1_ecdh.h
Normal file
63
libsecp256k1/include/secp256k1_ecdh.h
Normal file
@@ -0,0 +1,63 @@
|
||||
#ifndef SECP256K1_ECDH_H
|
||||
#define SECP256K1_ECDH_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/** A pointer to a function that hashes an EC point to obtain an ECDH secret
|
||||
*
|
||||
* Returns: 1 if the point was successfully hashed.
|
||||
* 0 will cause secp256k1_ecdh to fail and return 0.
|
||||
* Other return values are not allowed, and the behaviour of
|
||||
* secp256k1_ecdh is undefined for other return values.
|
||||
* Out: output: pointer to an array to be filled by the function
|
||||
* In: x32: pointer to a 32-byte x coordinate
|
||||
* y32: pointer to a 32-byte y coordinate
|
||||
* data: arbitrary data pointer that is passed through
|
||||
*/
|
||||
typedef int (*secp256k1_ecdh_hash_function)(
|
||||
unsigned char *output,
|
||||
const unsigned char *x32,
|
||||
const unsigned char *y32,
|
||||
void *data
|
||||
);
|
||||
|
||||
/** An implementation of SHA256 hash function that applies to compressed public key.
|
||||
* Populates the output parameter with 32 bytes. */
|
||||
SECP256K1_API const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_sha256;
|
||||
|
||||
/** A default ECDH hash function (currently equal to secp256k1_ecdh_hash_function_sha256).
|
||||
* Populates the output parameter with 32 bytes. */
|
||||
SECP256K1_API const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_default;
|
||||
|
||||
/** Compute an EC Diffie-Hellman secret in constant time
|
||||
*
|
||||
* Returns: 1: exponentiation was successful
|
||||
* 0: scalar was invalid (zero or overflow) or hashfp returned 0
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output: pointer to an array to be filled by hashfp.
|
||||
* In: pubkey: pointer to a secp256k1_pubkey containing an initialized public key.
|
||||
* seckey: a 32-byte scalar with which to multiply the point.
|
||||
* hashfp: pointer to a hash function. If NULL,
|
||||
* secp256k1_ecdh_hash_function_sha256 is used
|
||||
* (in which case, 32 bytes will be written to output).
|
||||
* data: arbitrary data pointer that is passed through to hashfp
|
||||
* (can be NULL for secp256k1_ecdh_hash_function_sha256).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdh(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output,
|
||||
const secp256k1_pubkey *pubkey,
|
||||
const unsigned char *seckey,
|
||||
secp256k1_ecdh_hash_function hashfp,
|
||||
void *data
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_ECDH_H */
|
||||
200
libsecp256k1/include/secp256k1_ellswift.h
Normal file
200
libsecp256k1/include/secp256k1_ellswift.h
Normal file
@@ -0,0 +1,200 @@
|
||||
#ifndef SECP256K1_ELLSWIFT_H
|
||||
#define SECP256K1_ELLSWIFT_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/* This module provides an implementation of ElligatorSwift as well as a
|
||||
* version of x-only ECDH using it (including compatibility with BIP324).
|
||||
*
|
||||
* ElligatorSwift is described in https://eprint.iacr.org/2022/759 by
|
||||
* Chavez-Saab, Rodriguez-Henriquez, and Tibouchi. It permits encoding
|
||||
* uniformly chosen public keys as 64-byte arrays which are indistinguishable
|
||||
* from uniformly random arrays.
|
||||
*
|
||||
* Let f be the function from pairs of field elements to point X coordinates,
|
||||
* defined as follows (all operations modulo p = 2^256 - 2^32 - 977)
|
||||
* f(u,t):
|
||||
* - Let C = 0xa2d2ba93507f1df233770c2a797962cc61f6d15da14ecd47d8d27ae1cd5f852,
|
||||
* a square root of -3.
|
||||
* - If u=0, set u=1 instead.
|
||||
* - If t=0, set t=1 instead.
|
||||
* - If u^3 + t^2 + 7 = 0, multiply t by 2.
|
||||
* - Let X = (u^3 + 7 - t^2) / (2 * t)
|
||||
* - Let Y = (X + t) / (C * u)
|
||||
* - Return the first in [u + 4 * Y^2, (-X/Y - u) / 2, (X/Y - u) / 2] that is an
|
||||
* X coordinate on the curve (at least one of them is, for any u and t).
|
||||
*
|
||||
* Then an ElligatorSwift encoding of x consists of the 32-byte big-endian
|
||||
* encodings of field elements u and t concatenated, where f(u,t) = x.
|
||||
* The encoding algorithm is described in the paper, and effectively picks a
|
||||
* uniformly random pair (u,t) among those which encode x.
|
||||
*
|
||||
* If the Y coordinate is relevant, it is given the same parity as t.
|
||||
*
|
||||
* Changes w.r.t. the paper:
|
||||
* - The u=0, t=0, and u^3+t^2+7=0 conditions result in decoding to the point
|
||||
* at infinity in the paper. Here they are remapped to finite points.
|
||||
* - The paper uses an additional encoding bit for the parity of y. Here the
|
||||
* parity of t is used (negating t does not affect the decoded x coordinate,
|
||||
* so this is possible).
|
||||
*
|
||||
* For mathematical background about the scheme, see the doc/ellswift.md file.
|
||||
*/
|
||||
|
||||
/** A pointer to a function used by secp256k1_ellswift_xdh to hash the shared X
|
||||
* coordinate along with the encoded public keys to a uniform shared secret.
|
||||
*
|
||||
* Returns: 1 if a shared secret was successfully computed.
|
||||
* 0 will cause secp256k1_ellswift_xdh to fail and return 0.
|
||||
* Other return values are not allowed, and the behaviour of
|
||||
* secp256k1_ellswift_xdh is undefined for other return values.
|
||||
* Out: output: pointer to an array to be filled by the function
|
||||
* In: x32: pointer to the 32-byte serialized X coordinate
|
||||
* of the resulting shared point (will not be NULL)
|
||||
* ell_a64: pointer to the 64-byte encoded public key of party A
|
||||
* (will not be NULL)
|
||||
* ell_b64: pointer to the 64-byte encoded public key of party B
|
||||
* (will not be NULL)
|
||||
* data: arbitrary data pointer that is passed through
|
||||
*/
|
||||
typedef int (*secp256k1_ellswift_xdh_hash_function)(
|
||||
unsigned char *output,
|
||||
const unsigned char *x32,
|
||||
const unsigned char *ell_a64,
|
||||
const unsigned char *ell_b64,
|
||||
void *data
|
||||
);
|
||||
|
||||
/** An implementation of an secp256k1_ellswift_xdh_hash_function which uses
|
||||
* SHA256(prefix64 || ell_a64 || ell_b64 || x32), where prefix64 is the 64-byte
|
||||
* array pointed to by data. */
|
||||
SECP256K1_API const secp256k1_ellswift_xdh_hash_function secp256k1_ellswift_xdh_hash_function_prefix;
|
||||
|
||||
/** An implementation of an secp256k1_ellswift_xdh_hash_function compatible with
|
||||
* BIP324. It returns H_tag(ell_a64 || ell_b64 || x32), where H_tag is the
|
||||
* BIP340 tagged hash function with tag "bip324_ellswift_xonly_ecdh". Equivalent
|
||||
* to secp256k1_ellswift_xdh_hash_function_prefix with prefix64 set to
|
||||
* SHA256("bip324_ellswift_xonly_ecdh")||SHA256("bip324_ellswift_xonly_ecdh").
|
||||
* The data argument is ignored. */
|
||||
SECP256K1_API const secp256k1_ellswift_xdh_hash_function secp256k1_ellswift_xdh_hash_function_bip324;
|
||||
|
||||
/** Construct a 64-byte ElligatorSwift encoding of a given pubkey.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: ell64: pointer to a 64-byte array to be filled
|
||||
* In: pubkey: pointer to a secp256k1_pubkey containing an
|
||||
* initialized public key
|
||||
* rnd32: pointer to 32 bytes of randomness
|
||||
*
|
||||
* It is recommended that rnd32 consists of 32 uniformly random bytes, not
|
||||
* known to any adversary trying to detect whether public keys are being
|
||||
* encoded, though 16 bytes of randomness (padded to an array of 32 bytes,
|
||||
* e.g., with zeros) suffice to make the result indistinguishable from
|
||||
* uniform. The randomness in rnd32 must not be a deterministic function of
|
||||
* the pubkey (it can be derived from the private key, though).
|
||||
*
|
||||
* It is not guaranteed that the computed encoding is stable across versions
|
||||
* of the library, even if all arguments to this function (including rnd32)
|
||||
* are the same.
|
||||
*
|
||||
* This function runs in variable time.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ellswift_encode(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *ell64,
|
||||
const secp256k1_pubkey *pubkey,
|
||||
const unsigned char *rnd32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Decode a 64-bytes ElligatorSwift encoded public key.
|
||||
*
|
||||
* Returns: always 1
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: pubkey: pointer to a secp256k1_pubkey that will be filled
|
||||
* In: ell64: pointer to a 64-byte array to decode
|
||||
*
|
||||
* This function runs in variable time.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ellswift_decode(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const unsigned char *ell64
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Compute an ElligatorSwift public key for a secret key.
|
||||
*
|
||||
* Returns: 1: secret was valid, public key was stored.
|
||||
* 0: secret was invalid, try again.
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: ell64: pointer to a 64-byte array to receive the ElligatorSwift
|
||||
* public key
|
||||
* In: seckey32: pointer to a 32-byte secret key
|
||||
* auxrnd32: (optional) pointer to 32 bytes of randomness
|
||||
*
|
||||
* Constant time in seckey and auxrnd32, but not in the resulting public key.
|
||||
*
|
||||
* It is recommended that auxrnd32 contains 32 uniformly random bytes, though
|
||||
* it is optional (and does result in encodings that are indistinguishable from
|
||||
* uniform even without any auxrnd32). It differs from the (mandatory) rnd32
|
||||
* argument to secp256k1_ellswift_encode in this regard.
|
||||
*
|
||||
* This function can be used instead of calling secp256k1_ec_pubkey_create
|
||||
* followed by secp256k1_ellswift_encode. It is safer, as it uses the secret
|
||||
* key as entropy for the encoding (supplemented with auxrnd32, if provided).
|
||||
*
|
||||
* Like secp256k1_ellswift_encode, this function does not guarantee that the
|
||||
* computed encoding is stable across versions of the library, even if all
|
||||
* arguments (including auxrnd32) are the same.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ellswift_create(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *ell64,
|
||||
const unsigned char *seckey32,
|
||||
const unsigned char *auxrnd32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Given a private key, and ElligatorSwift public keys sent in both directions,
|
||||
* compute a shared secret using x-only Elliptic Curve Diffie-Hellman (ECDH).
|
||||
*
|
||||
* Returns: 1: shared secret was successfully computed
|
||||
* 0: secret was invalid or hashfp returned 0
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output: pointer to an array to be filled by hashfp.
|
||||
* In: ell_a64: pointer to the 64-byte encoded public key of party A
|
||||
* (will not be NULL)
|
||||
* ell_b64: pointer to the 64-byte encoded public key of party B
|
||||
* (will not be NULL)
|
||||
* seckey32: pointer to our 32-byte secret key
|
||||
* party: boolean indicating which party we are: zero if we are
|
||||
* party A, non-zero if we are party B. seckey32 must be
|
||||
* the private key corresponding to that party's ell_?64.
|
||||
* This correspondence is not checked.
|
||||
* hashfp: pointer to a hash function.
|
||||
* data: arbitrary data pointer passed through to hashfp.
|
||||
*
|
||||
* Constant time in seckey32.
|
||||
*
|
||||
* This function is more efficient than decoding the public keys, and performing
|
||||
* ECDH on them.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ellswift_xdh(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output,
|
||||
const unsigned char *ell_a64,
|
||||
const unsigned char *ell_b64,
|
||||
const unsigned char *seckey32,
|
||||
int party,
|
||||
secp256k1_ellswift_xdh_hash_function hashfp,
|
||||
void *data
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5) SECP256K1_ARG_NONNULL(7);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_ELLSWIFT_H */
|
||||
250
libsecp256k1/include/secp256k1_extrakeys.h
Normal file
250
libsecp256k1/include/secp256k1_extrakeys.h
Normal file
@@ -0,0 +1,250 @@
|
||||
#ifndef SECP256K1_EXTRAKEYS_H
|
||||
#define SECP256K1_EXTRAKEYS_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/** Opaque data structure that holds a parsed and valid "x-only" public key.
|
||||
* An x-only pubkey encodes a point whose Y coordinate is even. It is
|
||||
* serialized using only its X coordinate (32 bytes). See BIP-340 for more
|
||||
* information about x-only pubkeys.
|
||||
*
|
||||
* The exact representation of data inside is implementation defined and not
|
||||
* guaranteed to be portable between different platforms or versions. It is
|
||||
* however guaranteed to be 64 bytes in size, and can be safely copied/moved.
|
||||
* If you need to convert to a format suitable for storage, transmission, use
|
||||
* use secp256k1_xonly_pubkey_serialize and secp256k1_xonly_pubkey_parse. To
|
||||
* compare keys, use secp256k1_xonly_pubkey_cmp.
|
||||
*/
|
||||
typedef struct secp256k1_xonly_pubkey {
|
||||
unsigned char data[64];
|
||||
} secp256k1_xonly_pubkey;
|
||||
|
||||
/** Opaque data structure that holds a keypair consisting of a secret and a
|
||||
* public key.
|
||||
*
|
||||
* The exact representation of data inside is implementation defined and not
|
||||
* guaranteed to be portable between different platforms or versions. It is
|
||||
* however guaranteed to be 96 bytes in size, and can be safely copied/moved.
|
||||
*/
|
||||
typedef struct secp256k1_keypair {
|
||||
unsigned char data[96];
|
||||
} secp256k1_keypair;
|
||||
|
||||
/** Parse a 32-byte sequence into a xonly_pubkey object.
|
||||
*
|
||||
* Returns: 1 if the public key was fully valid.
|
||||
* 0 if the public key could not be parsed or is invalid.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to a
|
||||
* parsed version of input. If not, it's set to an invalid value.
|
||||
* In: input32: pointer to a serialized xonly_pubkey.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_parse(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_xonly_pubkey *pubkey,
|
||||
const unsigned char *input32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Serialize an xonly_pubkey object into a 32-byte sequence.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output32: pointer to a 32-byte array to place the serialized key in.
|
||||
* In: pubkey: pointer to a secp256k1_xonly_pubkey containing an initialized public key.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_xonly_pubkey_serialize(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output32,
|
||||
const secp256k1_xonly_pubkey *pubkey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Compare two x-only public keys using lexicographic order
|
||||
*
|
||||
* Returns: <0 if the first public key is less than the second
|
||||
* >0 if the first public key is greater than the second
|
||||
* 0 if the two public keys are equal
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: pubkey1: first public key to compare
|
||||
* pubkey2: second public key to compare
|
||||
*/
|
||||
SECP256K1_API int secp256k1_xonly_pubkey_cmp(
|
||||
const secp256k1_context *ctx,
|
||||
const secp256k1_xonly_pubkey *pk1,
|
||||
const secp256k1_xonly_pubkey *pk2
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Converts a secp256k1_pubkey into a secp256k1_xonly_pubkey.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: xonly_pubkey: pointer to an x-only public key object for placing the converted public key.
|
||||
* pk_parity: Ignored if NULL. Otherwise, pointer to an integer that
|
||||
* will be set to 1 if the point encoded by xonly_pubkey is
|
||||
* the negation of the pubkey and set to 0 otherwise.
|
||||
* In: pubkey: pointer to a public key that is converted.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_from_pubkey(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_xonly_pubkey *xonly_pubkey,
|
||||
int *pk_parity,
|
||||
const secp256k1_pubkey *pubkey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Tweak an x-only public key by adding the generator multiplied with tweak32
|
||||
* to it.
|
||||
*
|
||||
* Note that the resulting point can not in general be represented by an x-only
|
||||
* pubkey because it may have an odd Y coordinate. Instead, the output_pubkey
|
||||
* is a normal secp256k1_pubkey.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid or the resulting public key would be
|
||||
* invalid (only when the tweak is the negation of the corresponding
|
||||
* secret key). 1 otherwise.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output_pubkey: pointer to a public key to store the result. Will be set
|
||||
* to an invalid value if this function returns 0.
|
||||
* In: internal_pubkey: pointer to an x-only pubkey to apply the tweak to.
|
||||
* tweak32: pointer to a 32-byte tweak, which must be valid
|
||||
* according to secp256k1_ec_seckey_verify or 32 zero
|
||||
* bytes. For uniformly random 32-byte tweaks, the chance of
|
||||
* being invalid is negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_tweak_add(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *output_pubkey,
|
||||
const secp256k1_xonly_pubkey *internal_pubkey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Checks that a tweaked pubkey is the result of calling
|
||||
* secp256k1_xonly_pubkey_tweak_add with internal_pubkey and tweak32.
|
||||
*
|
||||
* The tweaked pubkey is represented by its 32-byte x-only serialization and
|
||||
* its pk_parity, which can both be obtained by converting the result of
|
||||
* tweak_add to a secp256k1_xonly_pubkey.
|
||||
*
|
||||
* Note that this alone does _not_ verify that the tweaked pubkey is a
|
||||
* commitment. If the tweak is not chosen in a specific way, the tweaked pubkey
|
||||
* can easily be the result of a different internal_pubkey and tweak.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid or the tweaked pubkey is not the
|
||||
* result of tweaking the internal_pubkey with tweak32. 1 otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: tweaked_pubkey32: pointer to a serialized xonly_pubkey.
|
||||
* tweaked_pk_parity: the parity of the tweaked pubkey (whose serialization
|
||||
* is passed in as tweaked_pubkey32). This must match the
|
||||
* pk_parity value that is returned when calling
|
||||
* secp256k1_xonly_pubkey with the tweaked pubkey, or
|
||||
* this function will fail.
|
||||
* internal_pubkey: pointer to an x-only public key object to apply the tweak to.
|
||||
* tweak32: pointer to a 32-byte tweak.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_tweak_add_check(
|
||||
const secp256k1_context *ctx,
|
||||
const unsigned char *tweaked_pubkey32,
|
||||
int tweaked_pk_parity,
|
||||
const secp256k1_xonly_pubkey *internal_pubkey,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5);
|
||||
|
||||
/** Compute the keypair for a valid secret key.
|
||||
*
|
||||
* See the documentation of `secp256k1_ec_seckey_verify` for more information
|
||||
* about the validity of secret keys.
|
||||
*
|
||||
* Returns: 1: secret key is valid
|
||||
* 0: secret key is invalid
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: keypair: pointer to the created keypair.
|
||||
* In: seckey: pointer to a 32-byte secret key.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_create(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_keypair *keypair,
|
||||
const unsigned char *seckey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Get the secret key from a keypair.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: seckey: pointer to a 32-byte buffer for the secret key.
|
||||
* In: keypair: pointer to a keypair.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_sec(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *seckey,
|
||||
const secp256k1_keypair *keypair
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Get the public key from a keypair.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: pubkey: pointer to a pubkey object, set to the keypair public key.
|
||||
* In: keypair: pointer to a keypair.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_pub(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const secp256k1_keypair *keypair
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Get the x-only public key from a keypair.
|
||||
*
|
||||
* This is the same as calling secp256k1_keypair_pub and then
|
||||
* secp256k1_xonly_pubkey_from_pubkey.
|
||||
*
|
||||
* Returns: 1 always.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: pubkey: pointer to an xonly_pubkey object, set to the keypair
|
||||
* public key after converting it to an xonly_pubkey.
|
||||
* pk_parity: Ignored if NULL. Otherwise, pointer to an integer that will be set to the
|
||||
* pk_parity argument of secp256k1_xonly_pubkey_from_pubkey.
|
||||
* In: keypair: pointer to a keypair.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_xonly_pub(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_xonly_pubkey *pubkey,
|
||||
int *pk_parity,
|
||||
const secp256k1_keypair *keypair
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Tweak a keypair by adding tweak32 to the secret key and updating the public
|
||||
* key accordingly.
|
||||
*
|
||||
* Calling this function and then secp256k1_keypair_pub results in the same
|
||||
* public key as calling secp256k1_keypair_xonly_pub and then
|
||||
* secp256k1_xonly_pubkey_tweak_add.
|
||||
*
|
||||
* Returns: 0 if the arguments are invalid or the resulting keypair would be
|
||||
* invalid (only when the tweak is the negation of the keypair's
|
||||
* secret key). 1 otherwise.
|
||||
*
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In/Out: keypair: pointer to a keypair to apply the tweak to. Will be set to
|
||||
* an invalid value if this function returns 0.
|
||||
* In: tweak32: pointer to a 32-byte tweak, which must be valid according to
|
||||
* secp256k1_ec_seckey_verify or 32 zero bytes. For uniformly
|
||||
* random 32-byte tweaks, the chance of being invalid is
|
||||
* negligible (around 1 in 2^128).
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_xonly_tweak_add(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_keypair *keypair,
|
||||
const unsigned char *tweak32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_EXTRAKEYS_H */
|
||||
134
libsecp256k1/include/secp256k1_preallocated.h
Normal file
134
libsecp256k1/include/secp256k1_preallocated.h
Normal file
@@ -0,0 +1,134 @@
|
||||
#ifndef SECP256K1_PREALLOCATED_H
|
||||
#define SECP256K1_PREALLOCATED_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/* The module provided by this header file is intended for settings in which it
|
||||
* is not possible or desirable to rely on dynamic memory allocation. It provides
|
||||
* functions for creating, cloning, and destroying secp256k1 context objects in a
|
||||
* contiguous fixed-size block of memory provided by the caller.
|
||||
*
|
||||
* Context objects created by functions in this module can be used like contexts
|
||||
* objects created by functions in secp256k1.h, i.e., they can be passed to any
|
||||
* API function that expects a context object (see secp256k1.h for details). The
|
||||
* only exception is that context objects created by functions in this module
|
||||
* must be destroyed using secp256k1_context_preallocated_destroy (in this
|
||||
* module) instead of secp256k1_context_destroy (in secp256k1.h).
|
||||
*
|
||||
* It is guaranteed that functions in this module will not call malloc or its
|
||||
* friends realloc, calloc, and free.
|
||||
*/
|
||||
|
||||
/** Determine the memory size of a secp256k1 context object to be created in
|
||||
* caller-provided memory.
|
||||
*
|
||||
* The purpose of this function is to determine how much memory must be provided
|
||||
* to secp256k1_context_preallocated_create.
|
||||
*
|
||||
* Returns: the required size of the caller-provided memory block
|
||||
* In: flags: which parts of the context to initialize.
|
||||
*/
|
||||
SECP256K1_API size_t secp256k1_context_preallocated_size(
|
||||
unsigned int flags
|
||||
) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Create a secp256k1 context object in caller-provided memory.
|
||||
*
|
||||
* The caller must provide a pointer to a rewritable contiguous block of memory
|
||||
* of size at least secp256k1_context_preallocated_size(flags) bytes, suitably
|
||||
* aligned to hold an object of any type.
|
||||
*
|
||||
* The block of memory is exclusively owned by the created context object during
|
||||
* the lifetime of this context object, which begins with the call to this
|
||||
* function and ends when a call to secp256k1_context_preallocated_destroy
|
||||
* (which destroys the context object again) returns. During the lifetime of the
|
||||
* context object, the caller is obligated not to access this block of memory,
|
||||
* i.e., the caller may not read or write the memory, e.g., by copying the memory
|
||||
* contents to a different location or trying to create a second context object
|
||||
* in the memory. In simpler words, the prealloc pointer (or any pointer derived
|
||||
* from it) should not be used during the lifetime of the context object.
|
||||
*
|
||||
* Returns: pointer to newly created context object.
|
||||
* In: prealloc: pointer to a rewritable contiguous block of memory of
|
||||
* size at least secp256k1_context_preallocated_size(flags)
|
||||
* bytes, as detailed above.
|
||||
* flags: which parts of the context to initialize.
|
||||
*
|
||||
* See secp256k1_context_create (in secp256k1.h) for further details.
|
||||
*
|
||||
* See also secp256k1_context_randomize (in secp256k1.h)
|
||||
* and secp256k1_context_preallocated_destroy.
|
||||
*/
|
||||
SECP256K1_API secp256k1_context *secp256k1_context_preallocated_create(
|
||||
void *prealloc,
|
||||
unsigned int flags
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Determine the memory size of a secp256k1 context object to be copied into
|
||||
* caller-provided memory.
|
||||
*
|
||||
* Returns: the required size of the caller-provided memory block.
|
||||
* In: ctx: pointer to a context to copy.
|
||||
*/
|
||||
SECP256K1_API size_t secp256k1_context_preallocated_clone_size(
|
||||
const secp256k1_context *ctx
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Copy a secp256k1 context object into caller-provided memory.
|
||||
*
|
||||
* The caller must provide a pointer to a rewritable contiguous block of memory
|
||||
* of size at least secp256k1_context_preallocated_size(flags) bytes, suitably
|
||||
* aligned to hold an object of any type.
|
||||
*
|
||||
* The block of memory is exclusively owned by the created context object during
|
||||
* the lifetime of this context object, see the description of
|
||||
* secp256k1_context_preallocated_create for details.
|
||||
*
|
||||
* Cloning secp256k1_context_static is not possible, and should not be emulated by
|
||||
* the caller (e.g., using memcpy). Create a new context instead.
|
||||
*
|
||||
* Returns: pointer to a newly created context object.
|
||||
* Args: ctx: pointer to a context to copy (not secp256k1_context_static).
|
||||
* In: prealloc: pointer to a rewritable contiguous block of memory of
|
||||
* size at least secp256k1_context_preallocated_size(flags)
|
||||
* bytes, as detailed above.
|
||||
*/
|
||||
SECP256K1_API secp256k1_context *secp256k1_context_preallocated_clone(
|
||||
const secp256k1_context *ctx,
|
||||
void *prealloc
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_WARN_UNUSED_RESULT;
|
||||
|
||||
/** Destroy a secp256k1 context object that has been created in
|
||||
* caller-provided memory.
|
||||
*
|
||||
* The context pointer may not be used afterwards.
|
||||
*
|
||||
* The context to destroy must have been created using
|
||||
* secp256k1_context_preallocated_create or secp256k1_context_preallocated_clone.
|
||||
* If the context has instead been created using secp256k1_context_create or
|
||||
* secp256k1_context_clone, the behaviour is undefined. In that case,
|
||||
* secp256k1_context_destroy must be used instead.
|
||||
*
|
||||
* If required, it is the responsibility of the caller to deallocate the block
|
||||
* of memory properly after this function returns, e.g., by calling free on the
|
||||
* preallocated pointer given to secp256k1_context_preallocated_create or
|
||||
* secp256k1_context_preallocated_clone.
|
||||
*
|
||||
* Args: ctx: pointer to a context to destroy, constructed using
|
||||
* secp256k1_context_preallocated_create or
|
||||
* secp256k1_context_preallocated_clone
|
||||
* (i.e., not secp256k1_context_static).
|
||||
*/
|
||||
SECP256K1_API void secp256k1_context_preallocated_destroy(
|
||||
secp256k1_context *ctx
|
||||
) SECP256K1_ARG_NONNULL(1);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_PREALLOCATED_H */
|
||||
113
libsecp256k1/include/secp256k1_recovery.h
Normal file
113
libsecp256k1/include/secp256k1_recovery.h
Normal file
@@ -0,0 +1,113 @@
|
||||
#ifndef SECP256K1_RECOVERY_H
|
||||
#define SECP256K1_RECOVERY_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/** Opaque data structure that holds a parsed ECDSA signature,
|
||||
* supporting pubkey recovery.
|
||||
*
|
||||
* The exact representation of data inside is implementation defined and not
|
||||
* guaranteed to be portable between different platforms or versions. It is
|
||||
* however guaranteed to be 65 bytes in size, and can be safely copied/moved.
|
||||
* If you need to convert to a format suitable for storage or transmission, use
|
||||
* the secp256k1_ecdsa_signature_serialize_* and
|
||||
* secp256k1_ecdsa_signature_parse_* functions.
|
||||
*
|
||||
* Furthermore, it is guaranteed that identical signatures (including their
|
||||
* recoverability) will have identical representation, so they can be
|
||||
* memcmp'ed.
|
||||
*/
|
||||
typedef struct secp256k1_ecdsa_recoverable_signature {
|
||||
unsigned char data[65];
|
||||
} secp256k1_ecdsa_recoverable_signature;
|
||||
|
||||
/** Parse a compact ECDSA signature (64 bytes + recovery id).
|
||||
*
|
||||
* Returns: 1 when the signature could be parsed, 0 otherwise
|
||||
* Args: ctx: pointer to a context object
|
||||
* Out: sig: pointer to a signature object
|
||||
* In: input64: pointer to a 64-byte compact signature
|
||||
* recid: the recovery id (0, 1, 2 or 3)
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_parse_compact(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_recoverable_signature *sig,
|
||||
const unsigned char *input64,
|
||||
int recid
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Convert a recoverable signature into a normal signature.
|
||||
*
|
||||
* Returns: 1
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: sig: pointer to a normal signature.
|
||||
* In: sigin: pointer to a recoverable signature.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_convert(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_signature *sig,
|
||||
const secp256k1_ecdsa_recoverable_signature *sigin
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
||||
|
||||
/** Serialize an ECDSA signature in compact format (64 bytes + recovery id).
|
||||
*
|
||||
* Returns: 1
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: output64: pointer to a 64-byte array of the compact signature.
|
||||
* recid: pointer to an integer to hold the recovery id.
|
||||
* In: sig: pointer to an initialized signature object.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_recoverable_signature_serialize_compact(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *output64,
|
||||
int *recid,
|
||||
const secp256k1_ecdsa_recoverable_signature *sig
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Create a recoverable ECDSA signature.
|
||||
*
|
||||
* Returns: 1: signature created
|
||||
* 0: the nonce generation function failed, or the secret key was invalid.
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: sig: pointer to an array where the signature will be placed.
|
||||
* In: msghash32: the 32-byte message hash being signed.
|
||||
* seckey: pointer to a 32-byte secret key.
|
||||
* noncefp: pointer to a nonce generation function. If NULL,
|
||||
* secp256k1_nonce_function_default is used.
|
||||
* ndata: pointer to arbitrary data used by the nonce generation function
|
||||
* (can be NULL for secp256k1_nonce_function_default).
|
||||
*/
|
||||
SECP256K1_API int secp256k1_ecdsa_sign_recoverable(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_ecdsa_recoverable_signature *sig,
|
||||
const unsigned char *msghash32,
|
||||
const unsigned char *seckey,
|
||||
secp256k1_nonce_function noncefp,
|
||||
const void *ndata
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Recover an ECDSA public key from a signature.
|
||||
*
|
||||
* Returns: 1: public key successfully recovered (which guarantees a correct signature).
|
||||
* 0: otherwise.
|
||||
* Args: ctx: pointer to a context object.
|
||||
* Out: pubkey: pointer to the recovered public key.
|
||||
* In: sig: pointer to initialized signature that supports pubkey recovery.
|
||||
* msghash32: the 32-byte message hash assumed to be signed.
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_recover(
|
||||
const secp256k1_context *ctx,
|
||||
secp256k1_pubkey *pubkey,
|
||||
const secp256k1_ecdsa_recoverable_signature *sig,
|
||||
const unsigned char *msghash32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_RECOVERY_H */
|
||||
190
libsecp256k1/include/secp256k1_schnorrsig.h
Normal file
190
libsecp256k1/include/secp256k1_schnorrsig.h
Normal file
@@ -0,0 +1,190 @@
|
||||
#ifndef SECP256K1_SCHNORRSIG_H
|
||||
#define SECP256K1_SCHNORRSIG_H
|
||||
|
||||
#include "secp256k1.h"
|
||||
#include "secp256k1_extrakeys.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/** This module implements a variant of Schnorr signatures compliant with
|
||||
* Bitcoin Improvement Proposal 340 "Schnorr Signatures for secp256k1"
|
||||
* (https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
|
||||
*/
|
||||
|
||||
/** A pointer to a function to deterministically generate a nonce.
|
||||
*
|
||||
* Same as secp256k1_nonce function with the exception of accepting an
|
||||
* additional pubkey argument and not requiring an attempt argument. The pubkey
|
||||
* argument can protect signature schemes with key-prefixed challenge hash
|
||||
* inputs against reusing the nonce when signing with the wrong precomputed
|
||||
* pubkey.
|
||||
*
|
||||
* Returns: 1 if a nonce was successfully generated. 0 will cause signing to
|
||||
* return an error.
|
||||
* Out: nonce32: pointer to a 32-byte array to be filled by the function
|
||||
* In: msg: the message being verified. Is NULL if and only if msglen
|
||||
* is 0.
|
||||
* msglen: the length of the message
|
||||
* key32: pointer to a 32-byte secret key (will not be NULL)
|
||||
* xonly_pk32: the 32-byte serialized xonly pubkey corresponding to key32
|
||||
* (will not be NULL)
|
||||
* algo: pointer to an array describing the signature
|
||||
* algorithm (will not be NULL)
|
||||
* algolen: the length of the algo array
|
||||
* data: arbitrary data pointer that is passed through
|
||||
*
|
||||
* Except for test cases, this function should compute some cryptographic hash of
|
||||
* the message, the key, the pubkey, the algorithm description, and data.
|
||||
*/
|
||||
typedef int (*secp256k1_nonce_function_hardened)(
|
||||
unsigned char *nonce32,
|
||||
const unsigned char *msg,
|
||||
size_t msglen,
|
||||
const unsigned char *key32,
|
||||
const unsigned char *xonly_pk32,
|
||||
const unsigned char *algo,
|
||||
size_t algolen,
|
||||
void *data
|
||||
);
|
||||
|
||||
/** An implementation of the nonce generation function as defined in Bitcoin
|
||||
* Improvement Proposal 340 "Schnorr Signatures for secp256k1"
|
||||
* (https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
|
||||
*
|
||||
* If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
|
||||
* auxiliary random data as defined in BIP-340. If the data pointer is NULL,
|
||||
* the nonce derivation procedure follows BIP-340 by setting the auxiliary
|
||||
* random data to zero. The algo argument must be non-NULL, otherwise the
|
||||
* function will fail and return 0. The hash will be tagged with algo.
|
||||
* Therefore, to create BIP-340 compliant signatures, algo must be set to
|
||||
* "BIP0340/nonce" and algolen to 13.
|
||||
*/
|
||||
SECP256K1_API const secp256k1_nonce_function_hardened secp256k1_nonce_function_bip340;
|
||||
|
||||
/** Data structure that contains additional arguments for schnorrsig_sign_custom.
|
||||
*
|
||||
* A schnorrsig_extraparams structure object can be initialized correctly by
|
||||
* setting it to SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT.
|
||||
*
|
||||
* Members:
|
||||
* magic: set to SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC at initialization
|
||||
* and has no other function than making sure the object is
|
||||
* initialized.
|
||||
* noncefp: pointer to a nonce generation function. If NULL,
|
||||
* secp256k1_nonce_function_bip340 is used
|
||||
* ndata: pointer to arbitrary data used by the nonce generation function
|
||||
* (can be NULL). If it is non-NULL and
|
||||
* secp256k1_nonce_function_bip340 is used, then ndata must be a
|
||||
* pointer to 32-byte auxiliary randomness as per BIP-340.
|
||||
*/
|
||||
typedef struct secp256k1_schnorrsig_extraparams {
|
||||
unsigned char magic[4];
|
||||
secp256k1_nonce_function_hardened noncefp;
|
||||
void *ndata;
|
||||
} secp256k1_schnorrsig_extraparams;
|
||||
|
||||
#define SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC { 0xda, 0x6f, 0xb3, 0x8c }
|
||||
#define SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT {\
|
||||
SECP256K1_SCHNORRSIG_EXTRAPARAMS_MAGIC,\
|
||||
NULL,\
|
||||
NULL\
|
||||
}
|
||||
|
||||
/** Create a Schnorr signature.
|
||||
*
|
||||
* Does _not_ strictly follow BIP-340 because it does not verify the resulting
|
||||
* signature. Instead, you can manually use secp256k1_schnorrsig_verify and
|
||||
* abort if it fails.
|
||||
*
|
||||
* This function only signs 32-byte messages. If you have messages of a
|
||||
* different size (or the same size but without a context-specific tag
|
||||
* prefix), it is recommended to create a 32-byte message hash with
|
||||
* secp256k1_tagged_sha256 and then sign the hash. Tagged hashing allows
|
||||
* providing an context-specific tag for domain separation. This prevents
|
||||
* signatures from being valid in multiple contexts by accident.
|
||||
*
|
||||
* Returns 1 on success, 0 on failure.
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: sig64: pointer to a 64-byte array to store the serialized signature.
|
||||
* In: msg32: the 32-byte message being signed.
|
||||
* keypair: pointer to an initialized keypair.
|
||||
* aux_rand32: 32 bytes of fresh randomness. While recommended to provide
|
||||
* this, it is only supplemental to security and can be NULL. A
|
||||
* NULL argument is treated the same as an all-zero one. See
|
||||
* BIP-340 "Default Signing" for a full explanation of this
|
||||
* argument and for guidance if randomness is expensive.
|
||||
*/
|
||||
SECP256K1_API int secp256k1_schnorrsig_sign32(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *sig64,
|
||||
const unsigned char *msg32,
|
||||
const secp256k1_keypair *keypair,
|
||||
const unsigned char *aux_rand32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
|
||||
|
||||
/** Same as secp256k1_schnorrsig_sign32, but DEPRECATED. Will be removed in
|
||||
* future versions. */
|
||||
SECP256K1_API int secp256k1_schnorrsig_sign(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *sig64,
|
||||
const unsigned char *msg32,
|
||||
const secp256k1_keypair *keypair,
|
||||
const unsigned char *aux_rand32
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4)
|
||||
SECP256K1_DEPRECATED("Use secp256k1_schnorrsig_sign32 instead");
|
||||
|
||||
/** Create a Schnorr signature with a more flexible API.
|
||||
*
|
||||
* Same arguments as secp256k1_schnorrsig_sign except that it allows signing
|
||||
* variable length messages and accepts a pointer to an extraparams object that
|
||||
* allows customizing signing by passing additional arguments.
|
||||
*
|
||||
* Equivalent to secp256k1_schnorrsig_sign32(..., aux_rand32) if msglen is 32
|
||||
* and extraparams is initialized as follows:
|
||||
* ```
|
||||
* secp256k1_schnorrsig_extraparams extraparams = SECP256K1_SCHNORRSIG_EXTRAPARAMS_INIT;
|
||||
* extraparams.ndata = (unsigned char*)aux_rand32;
|
||||
* ```
|
||||
*
|
||||
* Returns 1 on success, 0 on failure.
|
||||
* Args: ctx: pointer to a context object (not secp256k1_context_static).
|
||||
* Out: sig64: pointer to a 64-byte array to store the serialized signature.
|
||||
* In: msg: the message being signed. Can only be NULL if msglen is 0.
|
||||
* msglen: length of the message.
|
||||
* keypair: pointer to an initialized keypair.
|
||||
* extraparams: pointer to an extraparams object (can be NULL).
|
||||
*/
|
||||
SECP256K1_API int secp256k1_schnorrsig_sign_custom(
|
||||
const secp256k1_context *ctx,
|
||||
unsigned char *sig64,
|
||||
const unsigned char *msg,
|
||||
size_t msglen,
|
||||
const secp256k1_keypair *keypair,
|
||||
secp256k1_schnorrsig_extraparams *extraparams
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(5);
|
||||
|
||||
/** Verify a Schnorr signature.
|
||||
*
|
||||
* Returns: 1: correct signature
|
||||
* 0: incorrect signature
|
||||
* Args: ctx: pointer to a context object.
|
||||
* In: sig64: pointer to the 64-byte signature to verify.
|
||||
* msg: the message being verified. Can only be NULL if msglen is 0.
|
||||
* msglen: length of the message
|
||||
* pubkey: pointer to an x-only public key to verify with
|
||||
*/
|
||||
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_schnorrsig_verify(
|
||||
const secp256k1_context *ctx,
|
||||
const unsigned char *sig64,
|
||||
const unsigned char *msg,
|
||||
size_t msglen,
|
||||
const secp256k1_xonly_pubkey *pubkey
|
||||
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(5);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* SECP256K1_SCHNORRSIG_H */
|
||||
Reference in New Issue
Block a user