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