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4a243da47c
These functions are intended for compatibility with legacy software, and are not normally needed in new secp256k1 applications. They also do not obeying any particular standard (and likely cannot without without undermining their compatibility), and so are a better fit for contrib.
572 lines
24 KiB
C
572 lines
24 KiB
C
#ifndef _SECP256K1_
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# define _SECP256K1_
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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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/* These 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 the 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, private 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 (precomputed tables etc.).
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*
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* The purpose of context structures is to cache large precomputed data tables
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* that are expensive to construct, and also to maintain the randomization data
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* for blinding.
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*
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* Do not create a new context object for each operation, as construction is
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* far slower than all other API calls (~100 times slower than an ECDSA
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* verification).
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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 call 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 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, use
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* secp256k1_ec_pubkey_serialize and secp256k1_ec_pubkey_parse.
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*
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* Furthermore, it is guaranteed that identical public keys (ignoring
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* compression) will have identical representation, so they can be memcmp'ed.
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*/
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typedef struct {
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unsigned char data[64];
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} secp256k1_pubkey;
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/** Opaque data structured 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 or transmission, use
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* the secp256k1_ecdsa_signature_serialize_* and
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* secp256k1_ecdsa_signature_serialize_* functions.
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*
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* Furthermore, it is guaranteed to identical signatures will have identical
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* representation, so they can be memcmp'ed.
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*/
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typedef struct {
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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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# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
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# if SECP256K1_GNUC_PREREQ(2,7)
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# define SECP256K1_INLINE __inline__
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# elif (defined(_MSC_VER))
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# define SECP256K1_INLINE __inline
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# else
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# define SECP256K1_INLINE
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# endif
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# else
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# define SECP256K1_INLINE inline
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# endif
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#ifndef SECP256K1_API
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# if defined(_WIN32)
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# ifdef SECP256K1_BUILD
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# define SECP256K1_API __declspec(dllexport)
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# else
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# define SECP256K1_API
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# endif
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# elif defined(__GNUC__) && defined(SECP256K1_BUILD)
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# define SECP256K1_API __attribute__ ((visibility ("default")))
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# else
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# define SECP256K1_API
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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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/** Flags to pass to secp256k1_context_create. */
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# define SECP256K1_CONTEXT_VERIFY (1 << 0)
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# define SECP256K1_CONTEXT_SIGN (1 << 1)
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/** Flag to pass to secp256k1_ec_pubkey_serialize and secp256k1_ec_privkey_export. */
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# define SECP256K1_EC_COMPRESSED (1 << 0)
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/** Create a secp256k1 context object.
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*
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* Returns: a newly created context object.
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* In: flags: which parts of the context to initialize.
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*/
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SECP256K1_API secp256k1_context* secp256k1_context_create(
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unsigned int flags
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) SECP256K1_WARN_UNUSED_RESULT;
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/** Copies a secp256k1 context object.
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*
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* Returns: a newly created context object.
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* Args: ctx: an existing context to copy (cannot be NULL)
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*/
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SECP256K1_API secp256k1_context* secp256k1_context_clone(
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const secp256k1_context* ctx
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) SECP256K1_ARG_NONNULL(1) SECP256K1_WARN_UNUSED_RESULT;
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/** Destroy a secp256k1 context object.
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*
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* The context pointer may not be used afterwards.
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* Args: ctx: an existing context to destroy (cannot be NULL)
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*/
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SECP256K1_API void secp256k1_context_destroy(
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secp256k1_context* ctx
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);
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/** Set a callback function to be called when an illegal argument is passed to
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* an API call. It will only trigger for violations that are mentioned
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* explicitly in the header.
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*
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* The philosophy is that these shouldn't be dealt with through a
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* specific return value, as calling code should not have branches to deal with
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* the case that this code itself is broken.
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*
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* On the other hand, during debug stage, one would want to be informed about
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* such mistakes, and the default (crashing) may be inadvisable.
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* When this callback is triggered, the API function called is guaranteed not
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* to cause a crash, though its return value and output arguments are
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* undefined.
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*
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* Args: ctx: an existing context object (cannot be NULL)
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* In: fun: a pointer to a function to call when an illegal argument is
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* passed to the API, taking a message and an opaque pointer
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* (NULL restores a default handler that calls abort).
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* data: the opaque pointer to pass to fun above.
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*/
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SECP256K1_API void secp256k1_context_set_illegal_callback(
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secp256k1_context* ctx,
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void (*fun)(const char* message, void* data),
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const void* data
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) SECP256K1_ARG_NONNULL(1);
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/** Set a callback function to be called when an internal consistency check
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* fails. The default is crashing.
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*
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* This can only trigger in case of a hardware failure, miscompilation,
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* memory corruption, serious bug in the library, or other error would can
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* otherwise result in undefined behaviour. It will not trigger due to mere
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* incorrect usage of the API (see secp256k1_context_set_illegal_callback
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* for that). After this callback returns, anything may happen, including
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* crashing.
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*
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* Args: ctx: an existing context object (cannot be NULL)
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* In: fun: a pointer to a function to call when an interal error occurs,
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* taking a message and an opaque pointer (NULL restores a default
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* handler that calls abort).
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* data: the opaque pointer to pass to fun above.
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*/
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SECP256K1_API void secp256k1_context_set_error_callback(
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secp256k1_context* ctx,
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void (*fun)(const char* message, void* data),
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const void* data
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) SECP256K1_ARG_NONNULL(1);
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/** Parse a variable-length public key into the pubkey object.
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*
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* Returns: 1 if the public key was fully valid.
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* 0 if the public key could not be parsed or is invalid.
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* Args: ctx: a secp256k1 context object.
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* Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to a
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* parsed version of input. If not, its value is undefined.
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* In: input: pointer to a serialized public key
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* inputlen: length of the array pointed to by input
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*
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* This function supports parsing compressed (33 bytes, header byte 0x02 or
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* 0x03), uncompressed (65 bytes, header byte 0x04), or hybrid (65 bytes, header
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* byte 0x06 or 0x07) format public keys.
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*/
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SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_parse(
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const secp256k1_context* ctx,
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secp256k1_pubkey* pubkey,
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const unsigned char *input,
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size_t inputlen
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
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/** Serialize a pubkey object into a serialized byte sequence.
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*
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* Returns: 1 always.
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* Args: ctx: a secp256k1 context object.
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* Out: output: a pointer to a 65-byte (if compressed==0) or 33-byte (if
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* compressed==1) byte array to place the serialized key in.
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* outputlen: a pointer to an integer which will contain the serialized
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* size.
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* In: pubkey: a pointer to a secp256k1_pubkey containing an initialized
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* public key.
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* flags: SECP256K1_EC_COMPRESSED if serialization should be in
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* compressed format.
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*/
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SECP256K1_API int secp256k1_ec_pubkey_serialize(
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const secp256k1_context* ctx,
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unsigned char *output,
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size_t *outputlen,
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const secp256k1_pubkey* pubkey,
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unsigned int flags
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
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/** Parse an ECDSA signature in compact (64 bytes) format.
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*
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* Returns: 1 when the signature could be parsed, 0 otherwise.
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* Args: ctx: a secp256k1 context object
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* Out: sig: a pointer to a signature object
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* In: input64: a pointer to the 64-byte array to parse
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*
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* The signature must consist of a 32-byte big endian R value, followed by a
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* 32-byte big endian S value. If R or S fall outside of [0..order-1], the
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* encoding is invalid. R and S with value 0 are allowed in the encoding.
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*
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* After the call, sig will always be initialized. If parsing failed or R or
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* S are zero, the resulting sig value is guaranteed to fail validation for any
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* message and public key.
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*/
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SECP256K1_API int secp256k1_ecdsa_signature_parse_compact(
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const secp256k1_context* ctx,
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secp256k1_ecdsa_signature* sig,
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const unsigned char *input64
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
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/** Parse a DER ECDSA signature.
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*
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* Returns: 1 when the signature could be parsed, 0 otherwise.
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* Args: ctx: a secp256k1 context object
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* Out: sig: a pointer to a signature object
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* In: input: a pointer to the signature to be parsed
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* inputlen: the length of the array pointed to be input
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*
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* This function will accept any valid DER encoded signature, even if the
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* encoded numbers are out of range.
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*
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* After the call, sig will always be initialized. If parsing failed or the
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* encoded numbers are out of range, signature validation with it is
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* guaranteed to fail for every message and public key.
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*/
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SECP256K1_API int secp256k1_ecdsa_signature_parse_der(
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const secp256k1_context* ctx,
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secp256k1_ecdsa_signature* sig,
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const unsigned char *input,
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size_t inputlen
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
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/** Serialize an ECDSA signature in DER format.
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*
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* Returns: 1 if enough space was available to serialize, 0 otherwise
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* Args: ctx: a secp256k1 context object
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* Out: output: a pointer to an array to store the DER serialization
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* In/Out: outputlen: a pointer to a length integer. Initially, this integer
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* should be set to the length of output. After the call
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* it will be set to the length of the serialization (even
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* if 0 was returned).
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* In: sig: a pointer to an initialized signature object
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*/
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SECP256K1_API int secp256k1_ecdsa_signature_serialize_der(
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const secp256k1_context* ctx,
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unsigned char *output,
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size_t *outputlen,
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const secp256k1_ecdsa_signature* sig
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
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/** Serialize an ECDSA signature in compact (64 byte) format.
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*
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* Returns: 1
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* Args: ctx: a secp256k1 context object
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* Out: output64: a pointer to a 64-byte array to store the compact serialization
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* In: sig: a pointer to an initialized signature object
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*
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* See secp256k1_ecdsa_signature_parse_compact for details about the encoding.
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*/
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SECP256K1_API int secp256k1_ecdsa_signature_serialize_compact(
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const secp256k1_context* ctx,
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unsigned char *output64,
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const secp256k1_ecdsa_signature* sig
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
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/** Verify an ECDSA signature.
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*
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* Returns: 1: correct signature
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* 0: incorrect or unparseable signature
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* Args: ctx: a secp256k1 context object, initialized for verification.
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* In: sig: the signature being verified (cannot be NULL)
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* msg32: the 32-byte message hash being verified (cannot be NULL)
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* pubkey: pointer to an initialized public key to verify with (cannot be NULL)
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*
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* To avoid accepting malleable signatures, only ECDSA signatures in lower-S
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* form are accepted.
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*
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* If you need to accept ECDSA signatures from sources that do not obey this
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* rule, apply secp256k1_ecdsa_signature_normalize to the signature prior to
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* validation, but be aware that doing so results in malleable signatures.
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*
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* For details, see the comments for that function.
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*/
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SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_verify(
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const secp256k1_context* ctx,
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const secp256k1_ecdsa_signature *sig,
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const unsigned char *msg32,
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const secp256k1_pubkey *pubkey
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
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/** Convert a signature to a normalized lower-S form.
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*
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* Returns: 1 if sigin was not normalized, 0 if it already was.
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* Args: ctx: a secp256k1 context object
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* Out: sigout: a pointer to a signature to fill with the normalized form,
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* or copy if the input was already normalized. (can be NULL if
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* you're only interested in whether the input was already
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* normalized).
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* In: sigin: a pointer to a signature to check/normalize (cannot be NULL,
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* can be identical to sigout)
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*
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* With ECDSA a third-party can forge a second distinct signature of the same
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* message, given a single initial signature, but without knowing the key. This
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* is done by negating the S value modulo the order of the curve, 'flipping'
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* the sign of the random point R which is not included in the signature.
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*
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* Forgery of the same message isn't universally problematic, but in systems
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* where message malleability or uniqueness of signatures is important this can
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* cause issues. This forgery can be blocked by all verifiers forcing signers
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* to use a normalized form.
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*
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* The lower-S form reduces the size of signatures slightly on average when
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* variable length encodings (such as DER) are used and is cheap to verify,
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* making it a good choice. Security of always using lower-S is assured because
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* anyone can trivially modify a signature after the fact to enforce this
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* property anyway.
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*
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* The lower S value is always between 0x1 and
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* 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
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* inclusive.
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*
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* No other forms of ECDSA malleability are known and none seem likely, but
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* there is no formal proof that ECDSA, even with this additional restriction,
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* is free of other malleability. Commonly used serialization schemes will also
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* accept various non-unique encodings, so care should be taken when this
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* property is required for an application.
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*
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* The secp256k1_ecdsa_sign function will by default create signatures in the
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* lower-S form, and secp256k1_ecdsa_verify will not accept others. In case
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* signatures come from a system that cannot enforce this property,
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* secp256k1_ecdsa_signature_normalize must be called before verification.
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*/
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SECP256K1_API int secp256k1_ecdsa_signature_normalize(
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const secp256k1_context* ctx,
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secp256k1_ecdsa_signature *sigout,
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const secp256k1_ecdsa_signature *sigin
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) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
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|
|
|
/** 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 extern const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
|
|
|
|
/** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
|
|
SECP256K1_API extern const secp256k1_nonce_function secp256k1_nonce_function_default;
|
|
|
|
/** Create an ECDSA signature.
|
|
*
|
|
* Returns: 1: signature created
|
|
* 0: the nonce generation function failed, or the private key was invalid.
|
|
* Args: ctx: pointer to a context object, initialized for signing (cannot be NULL)
|
|
* Out: sig: pointer to an array where the signature will be placed (cannot be NULL)
|
|
* In: msg32: the 32-byte message hash being signed (cannot be NULL)
|
|
* seckey: pointer to a 32-byte secret key (cannot be NULL)
|
|
* 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)
|
|
*
|
|
* 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 *msg32,
|
|
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 ECDSA secret key.
|
|
*
|
|
* Returns: 1: secret key is valid
|
|
* 0: secret key is invalid
|
|
* Args: ctx: pointer to a context object (cannot be NULL)
|
|
* In: seckey: pointer to a 32-byte secret key (cannot be NULL)
|
|
*/
|
|
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, initialized for signing (cannot be NULL)
|
|
* Out: pubkey: pointer to the created public key (cannot be NULL)
|
|
* In: seckey: pointer to a 32-byte private key (cannot be NULL)
|
|
*/
|
|
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);
|
|
|
|
/** Tweak a private key by adding tweak to it.
|
|
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
|
|
* uniformly random 32-byte arrays, or if the resulting private key
|
|
* would be invalid (only when the tweak is the complement of the
|
|
* private key). 1 otherwise.
|
|
* Args: ctx: pointer to a context object (cannot be NULL).
|
|
* In/Out: seckey: pointer to a 32-byte private key.
|
|
* In: tweak: pointer to a 32-byte tweak.
|
|
*/
|
|
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
|
|
const secp256k1_context* ctx,
|
|
unsigned char *seckey,
|
|
const unsigned char *tweak
|
|
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
|
|
|
/** Tweak a public key by adding tweak times the generator to it.
|
|
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
|
|
* uniformly random 32-byte arrays, or if the resulting public key
|
|
* would be invalid (only when the tweak is the complement of the
|
|
* corresponding private key). 1 otherwise.
|
|
* Args: ctx: pointer to a context object initialized for validation
|
|
* (cannot be NULL).
|
|
* In/Out: pubkey: pointer to a public key object.
|
|
* In: tweak: pointer to a 32-byte tweak.
|
|
*/
|
|
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
|
|
const secp256k1_context* ctx,
|
|
secp256k1_pubkey *pubkey,
|
|
const unsigned char *tweak
|
|
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
|
|
|
/** Tweak a private key by multiplying it by a tweak.
|
|
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
|
|
* uniformly random 32-byte arrays, or equal to zero. 1 otherwise.
|
|
* Args: ctx: pointer to a context object (cannot be NULL).
|
|
* In/Out: seckey: pointer to a 32-byte private key.
|
|
* In: tweak: pointer to a 32-byte tweak.
|
|
*/
|
|
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
|
|
const secp256k1_context* ctx,
|
|
unsigned char *seckey,
|
|
const unsigned char *tweak
|
|
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
|
|
|
/** Tweak a public key by multiplying it by a tweak value.
|
|
* Returns: 0 if the tweak was out of range (chance of around 1 in 2^128 for
|
|
* uniformly random 32-byte arrays, or equal to zero. 1 otherwise.
|
|
* Args: ctx: pointer to a context object initialized for validation
|
|
* (cannot be NULL).
|
|
* In/Out: pubkey: pointer to a public key obkect.
|
|
* In: tweak: pointer to a 32-byte tweak.
|
|
*/
|
|
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
|
|
const secp256k1_context* ctx,
|
|
secp256k1_pubkey *pubkey,
|
|
const unsigned char *tweak
|
|
) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
|
|
|
/** Updates the context randomization.
|
|
* Returns: 1: randomization successfully updated
|
|
* 0: error
|
|
* Args: ctx: pointer to a context object (cannot be NULL)
|
|
* In: seed32: pointer to a 32-byte random seed (NULL resets to initial state)
|
|
*/
|
|
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 pubkey for placing the resulting public key
|
|
* (cannot be NULL)
|
|
* In: ins: pointer to array of pointers to public keys (cannot be NULL)
|
|
* n: the number of public keys to add together (must be at least 1)
|
|
* Use secp256k1_ec_pubkey_compress and secp256k1_ec_pubkey_decompress if the
|
|
* uncompressed format is needed.
|
|
*/
|
|
SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_combine(
|
|
const secp256k1_context* ctx,
|
|
secp256k1_pubkey *out,
|
|
const secp256k1_pubkey * const * ins,
|
|
int n
|
|
) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
|
|
|
|
# ifdef __cplusplus
|
|
}
|
|
# endif
|
|
|
|
#endif
|