1  /***********************************************************************
 2   * Copyright (c) 2014 Pieter Wuille                                    *
 3   * Distributed under the MIT software license, see the accompanying    *
 4   * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
 5   ***********************************************************************/
 6  
 7  #ifndef SECP256K1_HASH_H
 8  #define SECP256K1_HASH_H
 9  
10  #include <stdlib.h>
11  #include <stdint.h>
12  
13  typedef struct {
14      secp256k1_sha256_compression_function fn_sha256_compression;
15  } secp256k1_hash_ctx;
16  
17  static void secp256k1_hash_ctx_init(secp256k1_hash_ctx *hash_ctx);
18  
19  typedef struct {
20      uint32_t s[8];
21      unsigned char buf[64];
22      uint64_t bytes;
23  } secp256k1_sha256;
24  
25  static void secp256k1_sha256_initialize(secp256k1_sha256 *hash);
26  /* Initialize a SHA256 hash state with a precomputed midstate.
27   * The byte counter must be a multiple of 64, i.e., there must be no unwritten
28   * bytes in the buffer. */
29  static void secp256k1_sha256_initialize_midstate(secp256k1_sha256 *hash, uint64_t bytes, const uint32_t state[8]);
30  static void secp256k1_sha256_write(const secp256k1_hash_ctx *hash_ctx, secp256k1_sha256 *hash, const unsigned char *data, size_t size);
31  static void secp256k1_sha256_finalize(const secp256k1_hash_ctx *hash_ctx, secp256k1_sha256 *hash, unsigned char *out32);
32  static void secp256k1_sha256_clear(secp256k1_sha256 *hash);
33  
34  typedef struct {
35      secp256k1_sha256 inner, outer;
36  } secp256k1_hmac_sha256;
37  
38  static void secp256k1_hmac_sha256_initialize(const secp256k1_hash_ctx *hash_ctx, secp256k1_hmac_sha256 *hash, const unsigned char *key, size_t size);
39  static void secp256k1_hmac_sha256_write(const secp256k1_hash_ctx *hash_ctx, secp256k1_hmac_sha256 *hash, const unsigned char *data, size_t size);
40  static void secp256k1_hmac_sha256_finalize(const secp256k1_hash_ctx *hash_ctx, secp256k1_hmac_sha256 *hash, unsigned char *out32);
41  static void secp256k1_hmac_sha256_clear(secp256k1_hmac_sha256 *hash);
42  
43  typedef struct {
44      unsigned char v[32];
45      unsigned char k[32];
46      int retry;
47  } secp256k1_rfc6979_hmac_sha256;
48  
49  static void secp256k1_rfc6979_hmac_sha256_initialize(const secp256k1_hash_ctx *hash_ctx, secp256k1_rfc6979_hmac_sha256 *rng, const unsigned char *key, size_t keylen);
50  static void secp256k1_rfc6979_hmac_sha256_generate(const secp256k1_hash_ctx *hash_ctx, secp256k1_rfc6979_hmac_sha256 *rng, unsigned char *out, size_t outlen);
51  static void secp256k1_rfc6979_hmac_sha256_finalize(secp256k1_rfc6979_hmac_sha256 *rng);
52  static void secp256k1_rfc6979_hmac_sha256_clear(secp256k1_rfc6979_hmac_sha256 *rng);
53  
54  #endif /* SECP256K1_HASH_H */