Bitcoin Core  27.99.0 P2P Digital Currency
hash_impl.h
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1 /***********************************************************************
2  * Copyright (c) 2014 Pieter Wuille *
3  * Distributed under the MIT software license, see the accompanying *
5  ***********************************************************************/
6
7 #ifndef SECP256K1_HASH_IMPL_H
8 #define SECP256K1_HASH_IMPL_H
9
10 #include "hash.h"
11 #include "util.h"
12
13 #include <stdlib.h>
14 #include <stdint.h>
15 #include <string.h>
16
17 #define Ch(x,y,z) ((z) ^ ((x) & ((y) ^ (z))))
18 #define Maj(x,y,z) (((x) & (y)) | ((z) & ((x) | (y))))
19 #define Sigma0(x) (((x) >> 2 | (x) << 30) ^ ((x) >> 13 | (x) << 19) ^ ((x) >> 22 | (x) << 10))
20 #define Sigma1(x) (((x) >> 6 | (x) << 26) ^ ((x) >> 11 | (x) << 21) ^ ((x) >> 25 | (x) << 7))
21 #define sigma0(x) (((x) >> 7 | (x) << 25) ^ ((x) >> 18 | (x) << 14) ^ ((x) >> 3))
22 #define sigma1(x) (((x) >> 17 | (x) << 15) ^ ((x) >> 19 | (x) << 13) ^ ((x) >> 10))
23
24 #define Round(a,b,c,d,e,f,g,h,k,w) do { \
25  uint32_t t1 = (h) + Sigma1(e) + Ch((e), (f), (g)) + (k) + (w); \
26  uint32_t t2 = Sigma0(a) + Maj((a), (b), (c)); \
27  (d) += t1; \
28  (h) = t1 + t2; \
29 } while(0)
30
32  hash->s[0] = 0x6a09e667ul;
33  hash->s[1] = 0xbb67ae85ul;
34  hash->s[2] = 0x3c6ef372ul;
35  hash->s[3] = 0xa54ff53aul;
36  hash->s[4] = 0x510e527ful;
37  hash->s[5] = 0x9b05688cul;
38  hash->s[6] = 0x1f83d9abul;
39  hash->s[7] = 0x5be0cd19ul;
40  hash->bytes = 0;
41 }
42
44 static void secp256k1_sha256_transform(uint32_t* s, const unsigned char* buf) {
45  uint32_t a = s[0], b = s[1], c = s[2], d = s[3], e = s[4], f = s[5], g = s[6], h = s[7];
46  uint32_t w0, w1, w2, w3, w4, w5, w6, w7, w8, w9, w10, w11, w12, w13, w14, w15;
47
48  Round(a, b, c, d, e, f, g, h, 0x428a2f98, w0 = secp256k1_read_be32(&buf[0]));
49  Round(h, a, b, c, d, e, f, g, 0x71374491, w1 = secp256k1_read_be32(&buf[4]));
50  Round(g, h, a, b, c, d, e, f, 0xb5c0fbcf, w2 = secp256k1_read_be32(&buf[8]));
51  Round(f, g, h, a, b, c, d, e, 0xe9b5dba5, w3 = secp256k1_read_be32(&buf[12]));
52  Round(e, f, g, h, a, b, c, d, 0x3956c25b, w4 = secp256k1_read_be32(&buf[16]));
53  Round(d, e, f, g, h, a, b, c, 0x59f111f1, w5 = secp256k1_read_be32(&buf[20]));
54  Round(c, d, e, f, g, h, a, b, 0x923f82a4, w6 = secp256k1_read_be32(&buf[24]));
55  Round(b, c, d, e, f, g, h, a, 0xab1c5ed5, w7 = secp256k1_read_be32(&buf[28]));
56  Round(a, b, c, d, e, f, g, h, 0xd807aa98, w8 = secp256k1_read_be32(&buf[32]));
57  Round(h, a, b, c, d, e, f, g, 0x12835b01, w9 = secp256k1_read_be32(&buf[36]));
58  Round(g, h, a, b, c, d, e, f, 0x243185be, w10 = secp256k1_read_be32(&buf[40]));
59  Round(f, g, h, a, b, c, d, e, 0x550c7dc3, w11 = secp256k1_read_be32(&buf[44]));
60  Round(e, f, g, h, a, b, c, d, 0x72be5d74, w12 = secp256k1_read_be32(&buf[48]));
61  Round(d, e, f, g, h, a, b, c, 0x80deb1fe, w13 = secp256k1_read_be32(&buf[52]));
62  Round(c, d, e, f, g, h, a, b, 0x9bdc06a7, w14 = secp256k1_read_be32(&buf[56]));
63  Round(b, c, d, e, f, g, h, a, 0xc19bf174, w15 = secp256k1_read_be32(&buf[60]));
64
65  Round(a, b, c, d, e, f, g, h, 0xe49b69c1, w0 += sigma1(w14) + w9 + sigma0(w1));
66  Round(h, a, b, c, d, e, f, g, 0xefbe4786, w1 += sigma1(w15) + w10 + sigma0(w2));
67  Round(g, h, a, b, c, d, e, f, 0x0fc19dc6, w2 += sigma1(w0) + w11 + sigma0(w3));
68  Round(f, g, h, a, b, c, d, e, 0x240ca1cc, w3 += sigma1(w1) + w12 + sigma0(w4));
69  Round(e, f, g, h, a, b, c, d, 0x2de92c6f, w4 += sigma1(w2) + w13 + sigma0(w5));
70  Round(d, e, f, g, h, a, b, c, 0x4a7484aa, w5 += sigma1(w3) + w14 + sigma0(w6));
71  Round(c, d, e, f, g, h, a, b, 0x5cb0a9dc, w6 += sigma1(w4) + w15 + sigma0(w7));
72  Round(b, c, d, e, f, g, h, a, 0x76f988da, w7 += sigma1(w5) + w0 + sigma0(w8));
73  Round(a, b, c, d, e, f, g, h, 0x983e5152, w8 += sigma1(w6) + w1 + sigma0(w9));
74  Round(h, a, b, c, d, e, f, g, 0xa831c66d, w9 += sigma1(w7) + w2 + sigma0(w10));
75  Round(g, h, a, b, c, d, e, f, 0xb00327c8, w10 += sigma1(w8) + w3 + sigma0(w11));
76  Round(f, g, h, a, b, c, d, e, 0xbf597fc7, w11 += sigma1(w9) + w4 + sigma0(w12));
77  Round(e, f, g, h, a, b, c, d, 0xc6e00bf3, w12 += sigma1(w10) + w5 + sigma0(w13));
78  Round(d, e, f, g, h, a, b, c, 0xd5a79147, w13 += sigma1(w11) + w6 + sigma0(w14));
79  Round(c, d, e, f, g, h, a, b, 0x06ca6351, w14 += sigma1(w12) + w7 + sigma0(w15));
80  Round(b, c, d, e, f, g, h, a, 0x14292967, w15 += sigma1(w13) + w8 + sigma0(w0));
81
82  Round(a, b, c, d, e, f, g, h, 0x27b70a85, w0 += sigma1(w14) + w9 + sigma0(w1));
83  Round(h, a, b, c, d, e, f, g, 0x2e1b2138, w1 += sigma1(w15) + w10 + sigma0(w2));
84  Round(g, h, a, b, c, d, e, f, 0x4d2c6dfc, w2 += sigma1(w0) + w11 + sigma0(w3));
85  Round(f, g, h, a, b, c, d, e, 0x53380d13, w3 += sigma1(w1) + w12 + sigma0(w4));
86  Round(e, f, g, h, a, b, c, d, 0x650a7354, w4 += sigma1(w2) + w13 + sigma0(w5));
87  Round(d, e, f, g, h, a, b, c, 0x766a0abb, w5 += sigma1(w3) + w14 + sigma0(w6));
88  Round(c, d, e, f, g, h, a, b, 0x81c2c92e, w6 += sigma1(w4) + w15 + sigma0(w7));
89  Round(b, c, d, e, f, g, h, a, 0x92722c85, w7 += sigma1(w5) + w0 + sigma0(w8));
90  Round(a, b, c, d, e, f, g, h, 0xa2bfe8a1, w8 += sigma1(w6) + w1 + sigma0(w9));
91  Round(h, a, b, c, d, e, f, g, 0xa81a664b, w9 += sigma1(w7) + w2 + sigma0(w10));
92  Round(g, h, a, b, c, d, e, f, 0xc24b8b70, w10 += sigma1(w8) + w3 + sigma0(w11));
93  Round(f, g, h, a, b, c, d, e, 0xc76c51a3, w11 += sigma1(w9) + w4 + sigma0(w12));
94  Round(e, f, g, h, a, b, c, d, 0xd192e819, w12 += sigma1(w10) + w5 + sigma0(w13));
95  Round(d, e, f, g, h, a, b, c, 0xd6990624, w13 += sigma1(w11) + w6 + sigma0(w14));
96  Round(c, d, e, f, g, h, a, b, 0xf40e3585, w14 += sigma1(w12) + w7 + sigma0(w15));
97  Round(b, c, d, e, f, g, h, a, 0x106aa070, w15 += sigma1(w13) + w8 + sigma0(w0));
98
99  Round(a, b, c, d, e, f, g, h, 0x19a4c116, w0 += sigma1(w14) + w9 + sigma0(w1));
100  Round(h, a, b, c, d, e, f, g, 0x1e376c08, w1 += sigma1(w15) + w10 + sigma0(w2));
101  Round(g, h, a, b, c, d, e, f, 0x2748774c, w2 += sigma1(w0) + w11 + sigma0(w3));
102  Round(f, g, h, a, b, c, d, e, 0x34b0bcb5, w3 += sigma1(w1) + w12 + sigma0(w4));
103  Round(e, f, g, h, a, b, c, d, 0x391c0cb3, w4 += sigma1(w2) + w13 + sigma0(w5));
104  Round(d, e, f, g, h, a, b, c, 0x4ed8aa4a, w5 += sigma1(w3) + w14 + sigma0(w6));
105  Round(c, d, e, f, g, h, a, b, 0x5b9cca4f, w6 += sigma1(w4) + w15 + sigma0(w7));
106  Round(b, c, d, e, f, g, h, a, 0x682e6ff3, w7 += sigma1(w5) + w0 + sigma0(w8));
107  Round(a, b, c, d, e, f, g, h, 0x748f82ee, w8 += sigma1(w6) + w1 + sigma0(w9));
108  Round(h, a, b, c, d, e, f, g, 0x78a5636f, w9 += sigma1(w7) + w2 + sigma0(w10));
109  Round(g, h, a, b, c, d, e, f, 0x84c87814, w10 += sigma1(w8) + w3 + sigma0(w11));
110  Round(f, g, h, a, b, c, d, e, 0x8cc70208, w11 += sigma1(w9) + w4 + sigma0(w12));
111  Round(e, f, g, h, a, b, c, d, 0x90befffa, w12 += sigma1(w10) + w5 + sigma0(w13));
112  Round(d, e, f, g, h, a, b, c, 0xa4506ceb, w13 += sigma1(w11) + w6 + sigma0(w14));
113  Round(c, d, e, f, g, h, a, b, 0xbef9a3f7, w14 + sigma1(w12) + w7 + sigma0(w15));
114  Round(b, c, d, e, f, g, h, a, 0xc67178f2, w15 + sigma1(w13) + w8 + sigma0(w0));
115
116  s[0] += a;
117  s[1] += b;
118  s[2] += c;
119  s[3] += d;
120  s[4] += e;
121  s[5] += f;
122  s[6] += g;
123  s[7] += h;
124 }
125
126 static void secp256k1_sha256_write(secp256k1_sha256 *hash, const unsigned char *data, size_t len) {
127  size_t bufsize = hash->bytes & 0x3F;
128  hash->bytes += len;
129  VERIFY_CHECK(hash->bytes >= len);
130  while (len >= 64 - bufsize) {
131  /* Fill the buffer, and process it. */
132  size_t chunk_len = 64 - bufsize;
133  memcpy(hash->buf + bufsize, data, chunk_len);
134  data += chunk_len;
135  len -= chunk_len;
136  secp256k1_sha256_transform(hash->s, hash->buf);
137  bufsize = 0;
138  }
139  if (len) {
140  /* Fill the buffer with what remains. */
141  memcpy(hash->buf + bufsize, data, len);
142  }
143 }
144
145 static void secp256k1_sha256_finalize(secp256k1_sha256 *hash, unsigned char *out32) {
146  static const unsigned char pad[64] = {0x80};
147  unsigned char sizedesc[8];
148  int i;
149  /* The maximum message size of SHA256 is 2^64-1 bits. */
150  VERIFY_CHECK(hash->bytes < ((uint64_t)1 << 61));
151  secp256k1_write_be32(&sizedesc[0], hash->bytes >> 29);
152  secp256k1_write_be32(&sizedesc[4], hash->bytes << 3);
153  secp256k1_sha256_write(hash, pad, 1 + ((119 - (hash->bytes % 64)) % 64));
154  secp256k1_sha256_write(hash, sizedesc, 8);
155  for (i = 0; i < 8; i++) {
156  secp256k1_write_be32(&out32[4*i], hash->s[i]);
157  hash->s[i] = 0;
158  }
159 }
160
161 /* Initializes a sha256 struct and writes the 64 byte string
162  * SHA256(tag)||SHA256(tag) into it. */
163 static void secp256k1_sha256_initialize_tagged(secp256k1_sha256 *hash, const unsigned char *tag, size_t taglen) {
164  unsigned char buf[32];
166  secp256k1_sha256_write(hash, tag, taglen);
167  secp256k1_sha256_finalize(hash, buf);
168
170  secp256k1_sha256_write(hash, buf, 32);
171  secp256k1_sha256_write(hash, buf, 32);
172 }
173
174 static void secp256k1_hmac_sha256_initialize(secp256k1_hmac_sha256 *hash, const unsigned char *key, size_t keylen) {
175  size_t n;
176  unsigned char rkey[64];
177  if (keylen <= sizeof(rkey)) {
178  memcpy(rkey, key, keylen);
179  memset(rkey + keylen, 0, sizeof(rkey) - keylen);
180  } else {
183  secp256k1_sha256_write(&sha256, key, keylen);
185  memset(rkey + 32, 0, 32);
186  }
187
189  for (n = 0; n < sizeof(rkey); n++) {
190  rkey[n] ^= 0x5c;
191  }
192  secp256k1_sha256_write(&hash->outer, rkey, sizeof(rkey));
193
195  for (n = 0; n < sizeof(rkey); n++) {
196  rkey[n] ^= 0x5c ^ 0x36;
197  }
198  secp256k1_sha256_write(&hash->inner, rkey, sizeof(rkey));
199  memset(rkey, 0, sizeof(rkey));
200 }
201
202 static void secp256k1_hmac_sha256_write(secp256k1_hmac_sha256 *hash, const unsigned char *data, size_t size) {
203  secp256k1_sha256_write(&hash->inner, data, size);
204 }
205
206 static void secp256k1_hmac_sha256_finalize(secp256k1_hmac_sha256 *hash, unsigned char *out32) {
207  unsigned char temp[32];
208  secp256k1_sha256_finalize(&hash->inner, temp);
209  secp256k1_sha256_write(&hash->outer, temp, 32);
210  memset(temp, 0, 32);
211  secp256k1_sha256_finalize(&hash->outer, out32);
212 }
213
214
215 static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256 *rng, const unsigned char *key, size_t keylen) {
217  static const unsigned char zero[1] = {0x00};
218  static const unsigned char one[1] = {0x01};
219
220  memset(rng->v, 0x01, 32); /* RFC6979 3.2.b. */
221  memset(rng->k, 0x00, 32); /* RFC6979 3.2.c. */
222
223  /* RFC6979 3.2.d. */
224  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
225  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
226  secp256k1_hmac_sha256_write(&hmac, zero, 1);
227  secp256k1_hmac_sha256_write(&hmac, key, keylen);
228  secp256k1_hmac_sha256_finalize(&hmac, rng->k);
229  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
230  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
231  secp256k1_hmac_sha256_finalize(&hmac, rng->v);
232
233  /* RFC6979 3.2.f. */
234  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
235  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
236  secp256k1_hmac_sha256_write(&hmac, one, 1);
237  secp256k1_hmac_sha256_write(&hmac, key, keylen);
238  secp256k1_hmac_sha256_finalize(&hmac, rng->k);
239  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
240  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
241  secp256k1_hmac_sha256_finalize(&hmac, rng->v);
242  rng->retry = 0;
243 }
244
245 static void secp256k1_rfc6979_hmac_sha256_generate(secp256k1_rfc6979_hmac_sha256 *rng, unsigned char *out, size_t outlen) {
246  /* RFC6979 3.2.h. */
247  static const unsigned char zero[1] = {0x00};
248  if (rng->retry) {
250  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
251  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
252  secp256k1_hmac_sha256_write(&hmac, zero, 1);
253  secp256k1_hmac_sha256_finalize(&hmac, rng->k);
254  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
255  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
256  secp256k1_hmac_sha256_finalize(&hmac, rng->v);
257  }
258
259  while (outlen > 0) {
261  int now = outlen;
262  secp256k1_hmac_sha256_initialize(&hmac, rng->k, 32);
263  secp256k1_hmac_sha256_write(&hmac, rng->v, 32);
264  secp256k1_hmac_sha256_finalize(&hmac, rng->v);
265  if (now > 32) {
266  now = 32;
267  }
268  memcpy(out, rng->v, now);
269  out += now;
270  outlen -= now;
271  }
272
273  rng->retry = 1;
274 }
275
277  memset(rng->k, 0, 32);
278  memset(rng->v, 0, 32);
279  rng->retry = 0;
280 }
281
282 #undef Round
283 #undef sigma1
284 #undef sigma0
285 #undef Sigma1
286 #undef Sigma0
287 #undef Maj
288 #undef Ch
289
290 #endif /* SECP256K1_HASH_IMPL_H */
#define sigma1(x)
Definition: hash_impl.h:22
static void secp256k1_sha256_initialize(secp256k1_sha256 *hash)
Definition: hash_impl.h:31
static void secp256k1_rfc6979_hmac_sha256_generate(secp256k1_rfc6979_hmac_sha256 *rng, unsigned char *out, size_t outlen)
Definition: hash_impl.h:245
static void secp256k1_sha256_transform(uint32_t *s, const unsigned char *buf)
Perform one SHA-256 transformation, processing 16 big endian 32-bit words.
Definition: hash_impl.h:44
static void secp256k1_hmac_sha256_finalize(secp256k1_hmac_sha256 *hash, unsigned char *out32)
Definition: hash_impl.h:206
#define Round(a, b, c, d, e, f, g, h, k, w)
Definition: hash_impl.h:24
#define sigma0(x)
Definition: hash_impl.h:21
static void secp256k1_sha256_finalize(secp256k1_sha256 *hash, unsigned char *out32)
Definition: hash_impl.h:145
static void secp256k1_rfc6979_hmac_sha256_initialize(secp256k1_rfc6979_hmac_sha256 *rng, const unsigned char *key, size_t keylen)
Definition: hash_impl.h:215
static void secp256k1_rfc6979_hmac_sha256_finalize(secp256k1_rfc6979_hmac_sha256 *rng)
Definition: hash_impl.h:276
static void secp256k1_sha256_write(secp256k1_sha256 *hash, const unsigned char *data, size_t len)
Definition: hash_impl.h:126
static void secp256k1_hmac_sha256_write(secp256k1_hmac_sha256 *hash, const unsigned char *data, size_t size)
Definition: hash_impl.h:202
static void secp256k1_sha256_initialize_tagged(secp256k1_sha256 *hash, const unsigned char *tag, size_t taglen)
Definition: hash_impl.h:163
static void secp256k1_hmac_sha256_initialize(secp256k1_hmac_sha256 *hash, const unsigned char *key, size_t keylen)
Definition: hash_impl.h:174
Internal SHA-256 implementation.
Definition: sha256.cpp:69
static SECP256K1_INLINE uint32_t secp256k1_read_be32(const unsigned char *p)
Definition: util.h:358
static SECP256K1_INLINE void secp256k1_write_be32(unsigned char *p, uint32_t x)
Definition: util.h:366
#define VERIFY_CHECK(cond)
Definition: util.h:153
secp256k1_sha256 outer
Definition: hash.h:24
secp256k1_sha256 inner
Definition: hash.h:24
unsigned char k[32]
Definition: hash.h:33
unsigned char v[32]
Definition: hash.h:32
uint64_t bytes
Definition: hash.h:16
unsigned char buf[64]
Definition: hash.h:15
uint32_t s[8]
Definition: hash.h:14