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sha.c
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1 /*
2  * Copyright (C) 2007 Michael Niedermayer <michaelni@gmx.at>
3  * Copyright (C) 2009 Konstantin Shishkov
4  * based on public domain SHA-1 code by Steve Reid <steve@edmweb.com>
5  * and on BSD-licensed SHA-2 code by Aaron D. Gifford
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include <string.h>
25 
26 #include "attributes.h"
27 #include "avutil.h"
28 #include "bswap.h"
29 #include "sha.h"
30 #include "intreadwrite.h"
31 #include "mem.h"
32 
33 /** hash context */
34 typedef struct AVSHA {
35  uint8_t digest_len; ///< digest length in 32-bit words
36  uint64_t count; ///< number of bytes in buffer
37  uint8_t buffer[64]; ///< 512-bit buffer of input values used in hash updating
38  uint32_t state[8]; ///< current hash value
39  /** function used to update hash for 512-bit input block */
40  void (*transform)(uint32_t *state, const uint8_t buffer[64]);
41 } AVSHA;
42 
43 const int av_sha_size = sizeof(AVSHA);
44 
45 struct AVSHA *av_sha_alloc(void)
46 {
47  return av_mallocz(sizeof(struct AVSHA));
48 }
49 
50 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
51 
52 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
53 #define blk0(i) (block[i] = AV_RB32(buffer + 4 * (i)))
54 #define blk(i) (block[i] = rol(block[(i)-3] ^ block[(i)-8] ^ block[(i)-14] ^ block[(i)-16], 1))
55 
56 #define R0(v,w,x,y,z,i) z += (((w)&((x)^(y)))^(y)) + blk0(i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
57 #define R1(v,w,x,y,z,i) z += (((w)&((x)^(y)))^(y)) + blk (i) + 0x5A827999 + rol(v, 5); w = rol(w, 30);
58 #define R2(v,w,x,y,z,i) z += ( (w)^(x) ^(y)) + blk (i) + 0x6ED9EBA1 + rol(v, 5); w = rol(w, 30);
59 #define R3(v,w,x,y,z,i) z += ((((w)|(x))&(y))|((w)&(x))) + blk (i) + 0x8F1BBCDC + rol(v, 5); w = rol(w, 30);
60 #define R4(v,w,x,y,z,i) z += ( (w)^(x) ^(y)) + blk (i) + 0xCA62C1D6 + rol(v, 5); w = rol(w, 30);
61 
62 /* Hash a single 512-bit block. This is the core of the algorithm. */
63 
64 static void sha1_transform(uint32_t state[5], const uint8_t buffer[64])
65 {
66  uint32_t block[80];
67  unsigned int i, a, b, c, d, e;
68 
69  a = state[0];
70  b = state[1];
71  c = state[2];
72  d = state[3];
73  e = state[4];
74 #if CONFIG_SMALL
75  for (i = 0; i < 80; i++) {
76  int t;
77  if (i < 16)
78  t = AV_RB32(buffer + 4 * i);
79  else
80  t = rol(block[i-3] ^ block[i-8] ^ block[i-14] ^ block[i-16], 1);
81  block[i] = t;
82  t += e + rol(a, 5);
83  if (i < 40) {
84  if (i < 20)
85  t += ((b&(c^d))^d) + 0x5A827999;
86  else
87  t += ( b^c ^d) + 0x6ED9EBA1;
88  } else {
89  if (i < 60)
90  t += (((b|c)&d)|(b&c)) + 0x8F1BBCDC;
91  else
92  t += ( b^c ^d) + 0xCA62C1D6;
93  }
94  e = d;
95  d = c;
96  c = rol(b, 30);
97  b = a;
98  a = t;
99  }
100 #else
101 
102 #define R1_0 \
103  R0(a, b, c, d, e, 0 + i); \
104  R0(e, a, b, c, d, 1 + i); \
105  R0(d, e, a, b, c, 2 + i); \
106  R0(c, d, e, a, b, 3 + i); \
107  R0(b, c, d, e, a, 4 + i); \
108  i += 5
109 
110  i = 0;
111  R1_0; R1_0; R1_0;
112  R0(a, b, c, d, e, 15);
113  R1(e, a, b, c, d, 16);
114  R1(d, e, a, b, c, 17);
115  R1(c, d, e, a, b, 18);
116  R1(b, c, d, e, a, 19);
117 
118 #define R1_20 \
119  R2(a, b, c, d, e, 0 + i); \
120  R2(e, a, b, c, d, 1 + i); \
121  R2(d, e, a, b, c, 2 + i); \
122  R2(c, d, e, a, b, 3 + i); \
123  R2(b, c, d, e, a, 4 + i); \
124  i += 5
125 
126  i = 20;
127  R1_20; R1_20; R1_20; R1_20;
128 
129 #define R1_40 \
130  R3(a, b, c, d, e, 0 + i); \
131  R3(e, a, b, c, d, 1 + i); \
132  R3(d, e, a, b, c, 2 + i); \
133  R3(c, d, e, a, b, 3 + i); \
134  R3(b, c, d, e, a, 4 + i); \
135  i += 5
136 
137  R1_40; R1_40; R1_40; R1_40;
138 
139 #define R1_60 \
140  R4(a, b, c, d, e, 0 + i); \
141  R4(e, a, b, c, d, 1 + i); \
142  R4(d, e, a, b, c, 2 + i); \
143  R4(c, d, e, a, b, 3 + i); \
144  R4(b, c, d, e, a, 4 + i); \
145  i += 5
146 
147  R1_60; R1_60; R1_60; R1_60;
148 #endif
149  state[0] += a;
150  state[1] += b;
151  state[2] += c;
152  state[3] += d;
153  state[4] += e;
154 }
155 
156 static const uint32_t K256[64] = {
157  0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
158  0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
159  0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
160  0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
161  0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
162  0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
163  0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
164  0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
165  0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
166  0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
167  0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
168  0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
169  0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
170  0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
171  0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
172  0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
173 };
174 
175 
176 #define Ch(x,y,z) (((x) & ((y) ^ (z))) ^ (z))
177 #define Maj(z,y,x) ((((x) | (y)) & (z)) | ((x) & (y)))
178 
179 #define Sigma0_256(x) (rol((x), 30) ^ rol((x), 19) ^ rol((x), 10))
180 #define Sigma1_256(x) (rol((x), 26) ^ rol((x), 21) ^ rol((x), 7))
181 #define sigma0_256(x) (rol((x), 25) ^ rol((x), 14) ^ ((x) >> 3))
182 #define sigma1_256(x) (rol((x), 15) ^ rol((x), 13) ^ ((x) >> 10))
183 
184 #undef blk
185 #define blk(i) (block[i] = block[i - 16] + sigma0_256(block[i - 15]) + \
186  sigma1_256(block[i - 2]) + block[i - 7])
187 
188 #define ROUND256(a,b,c,d,e,f,g,h) \
189  T1 += (h) + Sigma1_256(e) + Ch((e), (f), (g)) + K256[i]; \
190  (d) += T1; \
191  (h) = T1 + Sigma0_256(a) + Maj((a), (b), (c)); \
192  i++
193 
194 #define ROUND256_0_TO_15(a,b,c,d,e,f,g,h) \
195  T1 = blk0(i); \
196  ROUND256(a,b,c,d,e,f,g,h)
197 
198 #define ROUND256_16_TO_63(a,b,c,d,e,f,g,h) \
199  T1 = blk(i); \
200  ROUND256(a,b,c,d,e,f,g,h)
201 
202 static void sha256_transform(uint32_t *state, const uint8_t buffer[64])
203 {
204  unsigned int i, a, b, c, d, e, f, g, h;
205  uint32_t block[64];
206  uint32_t T1;
207 
208  a = state[0];
209  b = state[1];
210  c = state[2];
211  d = state[3];
212  e = state[4];
213  f = state[5];
214  g = state[6];
215  h = state[7];
216 #if CONFIG_SMALL
217  for (i = 0; i < 64; i++) {
218  uint32_t T2;
219  if (i < 16)
220  T1 = blk0(i);
221  else
222  T1 = blk(i);
223  T1 += h + Sigma1_256(e) + Ch(e, f, g) + K256[i];
224  T2 = Sigma0_256(a) + Maj(a, b, c);
225  h = g;
226  g = f;
227  f = e;
228  e = d + T1;
229  d = c;
230  c = b;
231  b = a;
232  a = T1 + T2;
233  }
234 #else
235 
236  i = 0;
237 #define R256_0 \
238  ROUND256_0_TO_15(a, b, c, d, e, f, g, h); \
239  ROUND256_0_TO_15(h, a, b, c, d, e, f, g); \
240  ROUND256_0_TO_15(g, h, a, b, c, d, e, f); \
241  ROUND256_0_TO_15(f, g, h, a, b, c, d, e); \
242  ROUND256_0_TO_15(e, f, g, h, a, b, c, d); \
243  ROUND256_0_TO_15(d, e, f, g, h, a, b, c); \
244  ROUND256_0_TO_15(c, d, e, f, g, h, a, b); \
245  ROUND256_0_TO_15(b, c, d, e, f, g, h, a)
246 
247  R256_0; R256_0;
248 
249 #define R256_16 \
250  ROUND256_16_TO_63(a, b, c, d, e, f, g, h); \
251  ROUND256_16_TO_63(h, a, b, c, d, e, f, g); \
252  ROUND256_16_TO_63(g, h, a, b, c, d, e, f); \
253  ROUND256_16_TO_63(f, g, h, a, b, c, d, e); \
254  ROUND256_16_TO_63(e, f, g, h, a, b, c, d); \
255  ROUND256_16_TO_63(d, e, f, g, h, a, b, c); \
256  ROUND256_16_TO_63(c, d, e, f, g, h, a, b); \
257  ROUND256_16_TO_63(b, c, d, e, f, g, h, a)
258 
259  R256_16; R256_16; R256_16;
260  R256_16; R256_16; R256_16;
261 #endif
262  state[0] += a;
263  state[1] += b;
264  state[2] += c;
265  state[3] += d;
266  state[4] += e;
267  state[5] += f;
268  state[6] += g;
269  state[7] += h;
270 }
271 
272 
273 av_cold int av_sha_init(AVSHA *ctx, int bits)
274 {
275  ctx->digest_len = bits >> 5;
276  switch (bits) {
277  case 160: // SHA-1
278  ctx->state[0] = 0x67452301;
279  ctx->state[1] = 0xEFCDAB89;
280  ctx->state[2] = 0x98BADCFE;
281  ctx->state[3] = 0x10325476;
282  ctx->state[4] = 0xC3D2E1F0;
283  ctx->transform = sha1_transform;
284  break;
285  case 224: // SHA-224
286  ctx->state[0] = 0xC1059ED8;
287  ctx->state[1] = 0x367CD507;
288  ctx->state[2] = 0x3070DD17;
289  ctx->state[3] = 0xF70E5939;
290  ctx->state[4] = 0xFFC00B31;
291  ctx->state[5] = 0x68581511;
292  ctx->state[6] = 0x64F98FA7;
293  ctx->state[7] = 0xBEFA4FA4;
294  ctx->transform = sha256_transform;
295  break;
296  case 256: // SHA-256
297  ctx->state[0] = 0x6A09E667;
298  ctx->state[1] = 0xBB67AE85;
299  ctx->state[2] = 0x3C6EF372;
300  ctx->state[3] = 0xA54FF53A;
301  ctx->state[4] = 0x510E527F;
302  ctx->state[5] = 0x9B05688C;
303  ctx->state[6] = 0x1F83D9AB;
304  ctx->state[7] = 0x5BE0CD19;
305  ctx->transform = sha256_transform;
306  break;
307  default:
308  return -1;
309  }
310  ctx->count = 0;
311  return 0;
312 }
313 
314 void av_sha_update(AVSHA* ctx, const uint8_t* data, unsigned int len)
315 {
316  unsigned int i, j;
317 
318  j = ctx->count & 63;
319  ctx->count += len;
320 #if CONFIG_SMALL
321  for (i = 0; i < len; i++) {
322  ctx->buffer[j++] = data[i];
323  if (64 == j) {
324  ctx->transform(ctx->state, ctx->buffer);
325  j = 0;
326  }
327  }
328 #else
329  if ((j + len) > 63) {
330  memcpy(&ctx->buffer[j], data, (i = 64 - j));
331  ctx->transform(ctx->state, ctx->buffer);
332  for (; i + 63 < len; i += 64)
333  ctx->transform(ctx->state, &data[i]);
334  j = 0;
335  } else
336  i = 0;
337  memcpy(&ctx->buffer[j], &data[i], len - i);
338 #endif
339 }
340 
341 void av_sha_final(AVSHA* ctx, uint8_t *digest)
342 {
343  int i;
344  uint64_t finalcount = av_be2ne64(ctx->count << 3);
345 
346  av_sha_update(ctx, "\200", 1);
347  while ((ctx->count & 63) != 56)
348  av_sha_update(ctx, "", 1);
349  av_sha_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
350  for (i = 0; i < ctx->digest_len; i++)
351  AV_WB32(digest + i*4, ctx->state[i]);
352 }
353 
354 #ifdef TEST
355 #include <stdio.h>
356 
357 int main(void)
358 {
359  int i, j, k;
360  AVSHA ctx;
361  unsigned char digest[32];
362  static const int lengths[3] = { 160, 224, 256 };
363 
364  for (j = 0; j < 3; j++) {
365  printf("Testing SHA-%d\n", lengths[j]);
366  for (k = 0; k < 3; k++) {
367  av_sha_init(&ctx, lengths[j]);
368  if (k == 0)
369  av_sha_update(&ctx, "abc", 3);
370  else if (k == 1)
371  av_sha_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
372  else
373  for (i = 0; i < 1000*1000; i++)
374  av_sha_update(&ctx, "a", 1);
375  av_sha_final(&ctx, digest);
376  for (i = 0; i < lengths[j] >> 3; i++)
377  printf("%02X", digest[i]);
378  putchar('\n');
379  }
380  switch (j) {
381  case 0:
382  //test vectors (from FIPS PUB 180-1)
383  printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
384  "84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
385  "34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
386  break;
387  case 1:
388  //test vectors (from FIPS PUB 180-2 Appendix A)
389  printf("23097d22 3405d822 8642a477 bda255b3 2aadbce4 bda0b3f7 e36c9da7\n"
390  "75388b16 512776cc 5dba5da1 fd890150 b0c6455c b4f58b19 52522525\n"
391  "20794655 980c91d8 bbb4c1ea 97618a4b f03f4258 1948b2ee 4ee7ad67\n");
392  break;
393  case 2:
394  //test vectors (from FIPS PUB 180-2)
395  printf("ba7816bf 8f01cfea 414140de 5dae2223 b00361a3 96177a9c b410ff61 f20015ad\n"
396  "248d6a61 d20638b8 e5c02693 0c3e6039 a33ce459 64ff2167 f6ecedd4 19db06c1\n"
397  "cdc76e5c 9914fb92 81a1c7e2 84d73e67 f1809a48 a497200e 046d39cc c7112cd0\n");
398  break;
399  }
400  }
401 
402  return 0;
403 }
404 #endif
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