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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  for (i = 0; i < 15; i += 5) {
102  R0(a, b, c, d, e, 0 + i);
103  R0(e, a, b, c, d, 1 + i);
104  R0(d, e, a, b, c, 2 + i);
105  R0(c, d, e, a, b, 3 + i);
106  R0(b, c, d, e, a, 4 + i);
107  }
108  R0(a, b, c, d, e, 15);
109  R1(e, a, b, c, d, 16);
110  R1(d, e, a, b, c, 17);
111  R1(c, d, e, a, b, 18);
112  R1(b, c, d, e, a, 19);
113  for (i = 20; i < 40; i += 5) {
114  R2(a, b, c, d, e, 0 + i);
115  R2(e, a, b, c, d, 1 + i);
116  R2(d, e, a, b, c, 2 + i);
117  R2(c, d, e, a, b, 3 + i);
118  R2(b, c, d, e, a, 4 + i);
119  }
120  for (; i < 60; i += 5) {
121  R3(a, b, c, d, e, 0 + i);
122  R3(e, a, b, c, d, 1 + i);
123  R3(d, e, a, b, c, 2 + i);
124  R3(c, d, e, a, b, 3 + i);
125  R3(b, c, d, e, a, 4 + i);
126  }
127  for (; i < 80; i += 5) {
128  R4(a, b, c, d, e, 0 + i);
129  R4(e, a, b, c, d, 1 + i);
130  R4(d, e, a, b, c, 2 + i);
131  R4(c, d, e, a, b, 3 + i);
132  R4(b, c, d, e, a, 4 + i);
133  }
134 #endif
135  state[0] += a;
136  state[1] += b;
137  state[2] += c;
138  state[3] += d;
139  state[4] += e;
140 }
141 
142 static const uint32_t K256[64] = {
143  0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
144  0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
145  0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
146  0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
147  0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
148  0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
149  0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
150  0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
151  0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
152  0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
153  0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
154  0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
155  0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
156  0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
157  0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
158  0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
159 };
160 
161 
162 #define Ch(x,y,z) (((x) & ((y) ^ (z))) ^ (z))
163 #define Maj(z,y,x) ((((x) | (y)) & (z)) | ((x) & (y)))
164 
165 #define Sigma0_256(x) (rol((x), 30) ^ rol((x), 19) ^ rol((x), 10))
166 #define Sigma1_256(x) (rol((x), 26) ^ rol((x), 21) ^ rol((x), 7))
167 #define sigma0_256(x) (rol((x), 25) ^ rol((x), 14) ^ ((x) >> 3))
168 #define sigma1_256(x) (rol((x), 15) ^ rol((x), 13) ^ ((x) >> 10))
169 
170 #undef blk
171 #define blk(i) (block[i] = block[i - 16] + sigma0_256(block[i - 15]) + \
172  sigma1_256(block[i - 2]) + block[i - 7])
173 
174 #define ROUND256(a,b,c,d,e,f,g,h) \
175  T1 += (h) + Sigma1_256(e) + Ch((e), (f), (g)) + K256[i]; \
176  (d) += T1; \
177  (h) = T1 + Sigma0_256(a) + Maj((a), (b), (c)); \
178  i++
179 
180 #define ROUND256_0_TO_15(a,b,c,d,e,f,g,h) \
181  T1 = blk0(i); \
182  ROUND256(a,b,c,d,e,f,g,h)
183 
184 #define ROUND256_16_TO_63(a,b,c,d,e,f,g,h) \
185  T1 = blk(i); \
186  ROUND256(a,b,c,d,e,f,g,h)
187 
188 static void sha256_transform(uint32_t *state, const uint8_t buffer[64])
189 {
190  unsigned int i, a, b, c, d, e, f, g, h;
191  uint32_t block[64];
192  uint32_t T1;
193 
194  a = state[0];
195  b = state[1];
196  c = state[2];
197  d = state[3];
198  e = state[4];
199  f = state[5];
200  g = state[6];
201  h = state[7];
202 #if CONFIG_SMALL
203  for (i = 0; i < 64; i++) {
204  uint32_t T2;
205  if (i < 16)
206  T1 = blk0(i);
207  else
208  T1 = blk(i);
209  T1 += h + Sigma1_256(e) + Ch(e, f, g) + K256[i];
210  T2 = Sigma0_256(a) + Maj(a, b, c);
211  h = g;
212  g = f;
213  f = e;
214  e = d + T1;
215  d = c;
216  c = b;
217  b = a;
218  a = T1 + T2;
219  }
220 #else
221  for (i = 0; i < 16 - 7;) {
222  ROUND256_0_TO_15(a, b, c, d, e, f, g, h);
223  ROUND256_0_TO_15(h, a, b, c, d, e, f, g);
224  ROUND256_0_TO_15(g, h, a, b, c, d, e, f);
225  ROUND256_0_TO_15(f, g, h, a, b, c, d, e);
226  ROUND256_0_TO_15(e, f, g, h, a, b, c, d);
227  ROUND256_0_TO_15(d, e, f, g, h, a, b, c);
228  ROUND256_0_TO_15(c, d, e, f, g, h, a, b);
229  ROUND256_0_TO_15(b, c, d, e, f, g, h, a);
230  }
231 
232  for (; i < 64 - 7;) {
233  ROUND256_16_TO_63(a, b, c, d, e, f, g, h);
234  ROUND256_16_TO_63(h, a, b, c, d, e, f, g);
235  ROUND256_16_TO_63(g, h, a, b, c, d, e, f);
236  ROUND256_16_TO_63(f, g, h, a, b, c, d, e);
237  ROUND256_16_TO_63(e, f, g, h, a, b, c, d);
238  ROUND256_16_TO_63(d, e, f, g, h, a, b, c);
239  ROUND256_16_TO_63(c, d, e, f, g, h, a, b);
240  ROUND256_16_TO_63(b, c, d, e, f, g, h, a);
241  }
242 #endif
243  state[0] += a;
244  state[1] += b;
245  state[2] += c;
246  state[3] += d;
247  state[4] += e;
248  state[5] += f;
249  state[6] += g;
250  state[7] += h;
251 }
252 
253 
254 av_cold int av_sha_init(AVSHA *ctx, int bits)
255 {
256  ctx->digest_len = bits >> 5;
257  switch (bits) {
258  case 160: // SHA-1
259  ctx->state[0] = 0x67452301;
260  ctx->state[1] = 0xEFCDAB89;
261  ctx->state[2] = 0x98BADCFE;
262  ctx->state[3] = 0x10325476;
263  ctx->state[4] = 0xC3D2E1F0;
264  ctx->transform = sha1_transform;
265  break;
266  case 224: // SHA-224
267  ctx->state[0] = 0xC1059ED8;
268  ctx->state[1] = 0x367CD507;
269  ctx->state[2] = 0x3070DD17;
270  ctx->state[3] = 0xF70E5939;
271  ctx->state[4] = 0xFFC00B31;
272  ctx->state[5] = 0x68581511;
273  ctx->state[6] = 0x64F98FA7;
274  ctx->state[7] = 0xBEFA4FA4;
275  ctx->transform = sha256_transform;
276  break;
277  case 256: // SHA-256
278  ctx->state[0] = 0x6A09E667;
279  ctx->state[1] = 0xBB67AE85;
280  ctx->state[2] = 0x3C6EF372;
281  ctx->state[3] = 0xA54FF53A;
282  ctx->state[4] = 0x510E527F;
283  ctx->state[5] = 0x9B05688C;
284  ctx->state[6] = 0x1F83D9AB;
285  ctx->state[7] = 0x5BE0CD19;
286  ctx->transform = sha256_transform;
287  break;
288  default:
289  return -1;
290  }
291  ctx->count = 0;
292  return 0;
293 }
294 
295 void av_sha_update(AVSHA* ctx, const uint8_t* data, unsigned int len)
296 {
297  unsigned int i, j;
298 
299  j = ctx->count & 63;
300  ctx->count += len;
301 #if CONFIG_SMALL
302  for (i = 0; i < len; i++) {
303  ctx->buffer[j++] = data[i];
304  if (64 == j) {
305  ctx->transform(ctx->state, ctx->buffer);
306  j = 0;
307  }
308  }
309 #else
310  if ((j + len) > 63) {
311  memcpy(&ctx->buffer[j], data, (i = 64 - j));
312  ctx->transform(ctx->state, ctx->buffer);
313  for (; i + 63 < len; i += 64)
314  ctx->transform(ctx->state, &data[i]);
315  j = 0;
316  } else
317  i = 0;
318  memcpy(&ctx->buffer[j], &data[i], len - i);
319 #endif
320 }
321 
322 void av_sha_final(AVSHA* ctx, uint8_t *digest)
323 {
324  int i;
325  uint64_t finalcount = av_be2ne64(ctx->count << 3);
326 
327  av_sha_update(ctx, "\200", 1);
328  while ((ctx->count & 63) != 56)
329  av_sha_update(ctx, "", 1);
330  av_sha_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
331  for (i = 0; i < ctx->digest_len; i++)
332  AV_WB32(digest + i*4, ctx->state[i]);
333 }
334 
335 #ifdef TEST
336 #include <stdio.h>
337 
338 int main(void)
339 {
340  int i, j, k;
341  AVSHA ctx;
342  unsigned char digest[32];
343  const int lengths[3] = { 160, 224, 256 };
344 
345  for (j = 0; j < 3; j++) {
346  printf("Testing SHA-%d\n", lengths[j]);
347  for (k = 0; k < 3; k++) {
348  av_sha_init(&ctx, lengths[j]);
349  if (k == 0)
350  av_sha_update(&ctx, "abc", 3);
351  else if (k == 1)
352  av_sha_update(&ctx, "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq", 56);
353  else
354  for (i = 0; i < 1000*1000; i++)
355  av_sha_update(&ctx, "a", 1);
356  av_sha_final(&ctx, digest);
357  for (i = 0; i < lengths[j] >> 3; i++)
358  printf("%02X", digest[i]);
359  putchar('\n');
360  }
361  switch (j) {
362  case 0:
363  //test vectors (from FIPS PUB 180-1)
364  printf("A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D\n"
365  "84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1\n"
366  "34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F\n");
367  break;
368  case 1:
369  //test vectors (from FIPS PUB 180-2 Appendix A)
370  printf("23097d22 3405d822 8642a477 bda255b3 2aadbce4 bda0b3f7 e36c9da7\n"
371  "75388b16 512776cc 5dba5da1 fd890150 b0c6455c b4f58b19 52522525\n"
372  "20794655 980c91d8 bbb4c1ea 97618a4b f03f4258 1948b2ee 4ee7ad67\n");
373  break;
374  case 2:
375  //test vectors (from FIPS PUB 180-2)
376  printf("ba7816bf 8f01cfea 414140de 5dae2223 b00361a3 96177a9c b410ff61 f20015ad\n"
377  "248d6a61 d20638b8 e5c02693 0c3e6039 a33ce459 64ff2167 f6ecedd4 19db06c1\n"
378  "cdc76e5c 9914fb92 81a1c7e2 84d73e67 f1809a48 a497200e 046d39cc c7112cd0\n");
379  break;
380  }
381  }
382 
383  return 0;
384 }
385 #endif
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