548 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			548 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _SECP256K1_
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| # define _SECP256K1_
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| 
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| # ifdef __cplusplus
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| extern "C" {
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| # endif
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| 
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| #include <stddef.h>
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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|  *  Note that this function also supports some violations of DER and even BER.
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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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| 
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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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| 
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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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| 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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| 
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| /** An implementation of RFC6979 (using HMAC-SHA256) as nonce generation function.
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|  * If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
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|  * extra entropy.
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|  */
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| extern const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
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| 
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| /** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
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| extern const secp256k1_nonce_function secp256k1_nonce_function_default;
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| 
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| /** Create an ECDSA signature.
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|  *
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|  *  Returns: 1: signature created
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|  *           0: the nonce generation function failed, or the private key was invalid.
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|  *  Args:    ctx:    pointer to a context object, initialized for signing (cannot be NULL)
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|  *  Out:     sig:    pointer to an array where the signature will be placed (cannot be NULL)
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|  *  In:      msg32:  the 32-byte message hash being signed (cannot be NULL)
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|  *           seckey: pointer to a 32-byte secret key (cannot be NULL)
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|  *           noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
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|  *           ndata:  pointer to arbitrary data used by the nonce generation function (can be NULL)
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|  *
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|  * The sig always has an s value in the lower half of the range (From 0x1
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|  * to 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
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|  * inclusive), unlike many other implementations.
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|  *
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|  * With ECDSA a third-party can can forge a second distinct signature
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|  * of the same message given a single initial signature without knowing
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|  * the key by setting s to its additive inverse mod-order, 'flipping' the
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|  * sign of the random point R which is not included in the signature.
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|  * Since the forgery is of the same message this isn't universally
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|  * problematic, but in systems where message malleability or uniqueness
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|  * of signatures is important this can cause issues.  This forgery can be
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|  * blocked by all verifiers forcing signers to use a canonical form. The
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|  * 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
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|  * verify, making it a good choice. Security of always using lower-S is
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|  * assured because anyone can trivially modify a signature after the
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|  * fact to enforce this property.  Adjusting it inside the signing
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|  * function avoids the need to re-serialize or have curve specific
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|  * constants outside of the library.  By always using a canonical form
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|  * even in applications where it isn't needed it becomes possible to
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|  * impose a requirement later if a need is discovered.
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|  * No other forms of ECDSA malleability are known and none seem likely,
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|  * but there is no formal proof that ECDSA, even with this additional
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|  * restriction, is free of other malleability.  Commonly used serialization
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|  * schemes will also accept various non-unique encodings, so care should
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|  * be taken when this property is required for an application.
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|  */
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| SECP256K1_API int secp256k1_ecdsa_sign(
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|     const secp256k1_context* ctx,
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|     secp256k1_ecdsa_signature *sig,
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|     const unsigned char *msg32,
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|     const unsigned char *seckey,
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|     secp256k1_nonce_function noncefp,
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|     const void *ndata
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| ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
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| 
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| /** Verify an ECDSA secret key.
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|  *
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|  *  Returns: 1: secret key is valid
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|  *           0: secret key is invalid
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|  *  Args:    ctx: pointer to a context object (cannot be NULL)
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|  *  In:      seckey: pointer to a 32-byte secret key (cannot be NULL)
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|  */
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| SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(
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|     const secp256k1_context* ctx,
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|     const unsigned char *seckey
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| ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
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| 
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| /** Compute the public key for a secret key.
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|  *
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|  *  Returns: 1: secret was valid, public key stores
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|  *           0: secret was invalid, try again
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|  *  Args:   ctx:        pointer to a context object, initialized for signing (cannot be NULL)
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|  *  Out:    pubkey:     pointer to the created public key (cannot be NULL)
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|  *  In:     seckey:     pointer to a 32-byte private key (cannot be NULL)
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|  */
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| SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
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|     const secp256k1_context* ctx,
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|     secp256k1_pubkey *pubkey,
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|     const unsigned char *seckey
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| ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
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| 
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| /** Export a private key in BER format.
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|  *
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|  *  Returns: 1 if the private key was valid.
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|  *  Args: ctx:        pointer to a context object, initialized for signing (cannot
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|  *                    be NULL)
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|  *  Out: privkey:     pointer to an array for storing the private key in BER.
 | |
|  *                    Should have space for 279 bytes, and cannot be NULL.
 | |
|  *       privkeylen:  Pointer to an int where the length of the private key in
 | |
|  *                    privkey will be stored.
 | |
|  *  In:  seckey:      pointer to a 32-byte secret key to export.
 | |
|  *       flags:       SECP256K1_EC_COMPRESSED if the key should be exported in
 | |
|  *                    compressed format.
 | |
|  *
 | |
|  *  This function is purely meant for compatibility with applications that
 | |
|  *  require BER encoded keys. When working with secp256k1-specific code, the
 | |
|  *  simple 32-byte private keys are sufficient.
 | |
|  *
 | |
|  *  Note that this function does not guarantee correct DER output. It is
 | |
|  *  guaranteed to be parsable by secp256k1_ec_privkey_import.
 | |
|  */
 | |
| SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_export(
 | |
|     const secp256k1_context* ctx,
 | |
|     unsigned char *privkey,
 | |
|     size_t *privkeylen,
 | |
|     const unsigned char *seckey,
 | |
|     unsigned int flags
 | |
| ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
 | |
| 
 | |
| /** Import a private key in DER format.
 | |
|  * Returns: 1 if a private key was extracted.
 | |
|  * Args: ctx:        pointer to a context object (cannot be NULL).
 | |
|  * Out:  seckey:     pointer to a 32-byte array for storing the private key.
 | |
|  *                   (cannot be NULL).
 | |
|  * In:   privkey:    pointer to a private key in DER format (cannot be NULL).
 | |
|  *       privkeylen: length of the DER private key pointed to be privkey.
 | |
|  *
 | |
|  * This function will accept more than just strict DER, and even allow some BER
 | |
|  * violations. The public key stored inside the DER-encoded private key is not
 | |
|  * verified for correctness, nor are the curve parameters. Use this function
 | |
|  * only if you know in advance it is supposed to contain a secp256k1 private
 | |
|  * key.
 | |
|  */
 | |
| SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_import(
 | |
|     const secp256k1_context* ctx,
 | |
|     unsigned char *seckey,
 | |
|     const unsigned char *privkey,
 | |
|     size_t privkeylen
 | |
| ) 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
 |