FFmpeg
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 
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 
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 AVERROR(EINVAL);
309  }
310  ctx->count = 0;
311  return 0;
312 }
313 
314 void av_sha_update(struct AVSHA *ctx, const uint8_t *data, size_t len)
315 {
316  unsigned int j;
317  size_t i;
318 
319  j = ctx->count & 63;
320  ctx->count += len;
321 #if CONFIG_SMALL
322  for (i = 0; i < len; i++) {
323  ctx->buffer[j++] = data[i];
324  if (64 == j) {
325  ctx->transform(ctx->state, ctx->buffer);
326  j = 0;
327  }
328  }
329 #else
330  if (len >= 64 - j) {
331  const uint8_t *end;
332  memcpy(&ctx->buffer[j], data, (i = 64 - j));
333  ctx->transform(ctx->state, ctx->buffer);
334  data += i;
335  len -= i;
336  end = data + (len & ~63);
337  len = len % 64;
338  for (; data < end; data += 64)
339  ctx->transform(ctx->state, data);
340  j = 0;
341  }
342  memcpy(&ctx->buffer[j], data, len);
343 #endif
344 }
345 
346 void av_sha_final(AVSHA* ctx, uint8_t *digest)
347 {
348  int i;
349  uint64_t finalcount = av_be2ne64(ctx->count << 3);
350 
351  av_sha_update(ctx, "\200", 1);
352  while ((ctx->count & 63) != 56)
353  av_sha_update(ctx, "", 1);
354  av_sha_update(ctx, (uint8_t *)&finalcount, 8); /* Should cause a transform() */
355  for (i = 0; i < ctx->digest_len; i++)
356  AV_WB32(digest + i*4, ctx->state[i]);
357 }
AVSHA::transform
void(* transform)(uint32_t *state, const uint8_t buffer[64])
function used to update hash for 512-bit input block
Definition: sha.c:40
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
R0
#define R0(v, w, x, y, z, i)
Definition: sha.c:56
state
static struct @321 state
av_be2ne64
#define av_be2ne64(x)
Definition: bswap.h:94
av_sha_init
av_cold int av_sha_init(AVSHA *ctx, int bits)
Initialize SHA-1 or SHA-2 hashing.
Definition: sha.c:273
K256
static const uint32_t K256[64]
Definition: sha.c:156
b
#define b
Definition: input.c:41
data
const char data[16]
Definition: mxf.c:142
AVSHA::state
uint32_t state[8]
current hash value
Definition: sha.c:38
av_cold
#define av_cold
Definition: attributes.h:90
R1_20
#define R1_20
AVSHA::buffer
uint8_t buffer[64]
512-bit buffer of input values used in hash updating
Definition: sha.c:37
intreadwrite.h
g
const char * g
Definition: vf_curves.c:117
R256_0
#define R256_0
sha256_transform
static void sha256_transform(uint32_t *state, const uint8_t buffer[64])
Definition: sha.c:202
bits
uint8_t bits
Definition: vp3data.h:141
ctx
AVFormatContext * ctx
Definition: movenc.c:48
blk
#define blk(i)
Definition: sha.c:185
f
#define f(width, name)
Definition: cbs_vp9.c:255
av_sha_final
void av_sha_final(AVSHA *ctx, uint8_t *digest)
Finish hashing and output digest value.
Definition: sha.c:346
Maj
#define Maj(z, y, x)
Definition: sha.c:177
av_sha_size
const int av_sha_size
Definition: sha.c:43
sha.h
R1_60
#define R1_60
AVSHA::digest_len
uint8_t digest_len
digest length in 32-bit words
Definition: sha.c:35
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AV_WB32
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
R1
#define R1(v, w, x, y, z, i)
Definition: sha.c:57
av_sha_update
void av_sha_update(struct AVSHA *ctx, const uint8_t *data, size_t len)
Update hash value.
Definition: sha.c:314
rol
#define rol(value, bits)
Definition: sha.c:50
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
attributes.h
Ch
#define Ch(x, y, z)
Definition: sha.c:176
AVSHA::count
uint64_t count
number of bytes in buffer
Definition: sha.c:36
av_sha_alloc
struct AVSHA * av_sha_alloc(void)
Allocate an AVSHA context.
Definition: sha.c:45
i
int i
Definition: input.c:407
R1_40
#define R1_40
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:243
len
int len
Definition: vorbis_enc_data.h:452
AVSHA
hash context
Definition: sha.c:34
bswap.h
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
sha1_transform
static void sha1_transform(uint32_t state[5], const uint8_t buffer[64])
Definition: sha.c:64
R256_16
#define R256_16
avutil.h
mem.h
d
d
Definition: ffmpeg_filter.c:156
blk0
#define blk0(i)
Definition: sha.c:53
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
h
h
Definition: vp9dsp_template.c:2038
Sigma0_256
#define Sigma0_256(x)
Definition: sha.c:179
Sigma1_256
#define Sigma1_256(x)
Definition: sha.c:180
R1_0
#define R1_0