File: sha1.c

package info (click to toggle)
tla 1.3.5%2Bdfsg1-2
  • links: PTS
  • area: main
  • in suites: bullseye, buster, sid, stretch
  • size: 22,292 kB
  • ctags: 11,952
  • sloc: ansic: 149,771; sh: 16,009; xml: 2,689; lisp: 1,927; makefile: 1,064; cpp: 363; tcl: 230; awk: 48; sed: 25
file content (471 lines) | stat: -rw-r--r-- 13,430 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
/* sha.c - Functions to compute the SHA1 hash (message-digest) of files
   or blocks of memory.  Complies to the NIST specification FIPS-180-1.

   Copyright (C) 2000, 2001, 2003 Scott G. Miller

   Modified for hackerlab:
   Copyright (C) 2004 Colin Walters <walters@verbum.org>

   Credits:
      Robert Klep <robert@ilse.nl>  -- Expansion function fix
*/

#include "hackerlab/bugs/panic.h"
#include "hackerlab/machine/endian.h"
#include "hackerlab/mem/mem.h"
#include "hackerlab/char/str.h"
#include "hackerlab/fmt/cvt.h"
#include "hackerlab/hash/sha1.h"

/*
  Not-swap is a macro that does an endian swap on architectures that are
  big-endian, as SHA needs some data in a little-endian format
*/


/************************************************************************
 *(h1 "SHA1 Routines")
 * 
 * The SHA1 routines allow you to compute an SHA1 message digest
 * According to the definition of SHA1 in RFC 3174 from September 2001.
 * 
 */


/* Structure to save state of computation between the single steps.  */
struct sha1_context
{
  sha1_t current_sha1;

  t_uint32 total[2];
  t_uint32 buflen;
  t_uchar buffer[128] __attribute__((aligned(4)));
};

static void
sha1_process_blocks (const t_uchar *buffer, size_t len, sha1_context_t ctx);

#if MACHINE_IS_BIGENDIAN
# define NOTSWAP(n) (n)
# define SWAP(n)							\
    (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
#else
# define NOTSWAP(n)                                                         \
    (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
# define SWAP(n) (n)
#endif

/* This array contains the bytes used to pad the buffer to the next
   64-byte boundary.  (RFC 1321, 3.1: Step 1)  */
static const t_uchar fillbuf[64] = { 0x80, 0 /* , 0, 0, ...  */ };

/*(c make_sha1_context)
 * sha1_context_t make_sha1_context (alloc_limits limits);
 * 
 * Allocate and initialize an object which will keep track of the
 * state of an sha1 digest computation.
 */
sha1_context_t
make_sha1_context (alloc_limits limits)
{
  sha1_context_t ctx = 0;

  ctx = lim_malloc (limits, sizeof (*ctx));
  sha1_context_reset (ctx);
  return ctx;
}

/*(c sha1_context_reset)
 * void sha1_context_reset (sha1_context_t ctx);
 * 
 * Reinitialize a SHA1 state object.  This will 
 * undo the effects of any previous calls to
 * `sha1_scan'.
 */
void
sha1_context_reset (sha1_context_t ctx)
{
  if (ctx)
    {
      ctx->current_sha1.A = 0x67452301;
      ctx->current_sha1.B = 0xefcdab89;
      ctx->current_sha1.C = 0x98badcfe;
      ctx->current_sha1.D = 0x10325476;
      ctx->current_sha1.E = 0xc3d2e1f0;
      
      ctx->total[0] = ctx->total[1] = 0;
      ctx->buflen = 0;
    }
}

/*(c free_sha1_context)
 * void free_sha1_context (alloc_limits limits, sha1_context_t ctx);
 * 
 * Free all resources associated with an sha1 state object.
 */
void
free_sha1_context (alloc_limits limits, sha1_context_t ctx)
{
  lim_free (limits, ctx);
}


/*(c sha1_scan)
 * void sha1_scan (sha1_context_t hd, t_uchar * inbuf, size_t inlen);
 * 
 * Scan the next `inlen' bytes of `inbuf', treating them as subsequent
 * bytes in a message for which we are computing an sha1 digest.
 * 
 * This function may be called repeatedly on sequential ``bursts'' 
 * of a total message.
 */
void
sha1_scan (sha1_context_t ctx, const t_uchar *buffer, size_t len)
{
  /* When we already have some bits in our internal buffer concatenate
     both inputs first.  */
  while (len > 0)
    {
      size_t left_over = ctx->buflen;
      size_t add = 128 - left_over > len ? len : 128 - left_over;

      mem_cpy (&ctx->buffer[left_over], buffer, add);
      ctx->buflen += add;

      if (ctx->buflen > 64)
	{
	  sha1_process_blocks (ctx->buffer, ctx->buflen & ~63, ctx);

	  ctx->buflen &= 63;
	  /* The regions in the following copy operation cannot overlap.  */
	  mem_cpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
		   ctx->buflen);
	}

      buffer = (const t_uchar *) buffer + add;
      len -= add;
    }

  /* Process available complete blocks.  */
  /*
  if (len >= 64)
    {
      sha1_process_blocks (buffer, len & ~63, ctx);
      buffer = (const t_uchar *) buffer + (len & ~63);
      len &= 63;
    }
  */

  /* Move remaining bytes in internal buffer.  */
  /*
  if (len > 0)
    {
      size_t left_over = ctx->buflen;

      mem_cpy (&ctx->buffer[left_over], buffer, len);
      left_over += len;
      if (left_over >= 64)
	{
	  sha1_process_blocks (ctx->buffer, 64, ctx);
	  left_over -= 64;
	  mem_cpy (ctx->buffer, &ctx->buffer[64], left_over);
	}
      ctx->buflen = left_over;
    }
  */
}



/*(c sha1_final)
 * void sha1_final (t_uchar * result, sha1_context_t ctx);
 * 
 * Declare that a complete message has been scanned using
 * `state' and `sha1_scan()'.
 * 
 * Return the 20-byte SHA1 digest in `result', which must point to
 * storage for at least 20 bytes.
 * 
 * As a side-effect, `state' is reinitialized and may be used
 * again with `sha1_scan ()' to process a new message.
 */
void
sha1_final (t_uchar *result, sha1_context_t ctx)
{
  /* Take yet unprocessed bytes into account.  */
  t_uint32 bytes = ctx->buflen;
  size_t pad;
  /* Temporary array for solving alignment issues */
  t_uint32 tmp[5];

  /* Now count remaining bytes.  */
  ctx->total[0] += bytes;
  if (ctx->total[0] < bytes)
    ++ctx->total[1];

  pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
  mem_cpy (&ctx->buffer[bytes], fillbuf, pad);

  /* Put the 64-bit file length in *bits* at the end of the buffer.  */
  *(t_uint32 *) &ctx->buffer[bytes + pad + 4] = NOTSWAP (ctx->total[0] << 3);
  *(t_uint32 *) &ctx->buffer[bytes + pad] = NOTSWAP ((ctx->total[1] << 3) |
						    (ctx->total[0] >> 29));

  /* Process last bytes.  */
  sha1_process_blocks (ctx->buffer, bytes + pad + 8, ctx);

  tmp[0] = NOTSWAP (ctx->current_sha1.A);
  tmp[1] = NOTSWAP (ctx->current_sha1.B);
  tmp[2] = NOTSWAP (ctx->current_sha1.C);
  tmp[3] = NOTSWAP (ctx->current_sha1.D);
  tmp[4] = NOTSWAP (ctx->current_sha1.E);
  mem_cpy (result, tmp, 20);
  
  sha1_context_reset (ctx);
}



/*(c sha1_alloc_ascii)
 * t_uchar * sha1_alloc_ascii (alloc_limits limits, t_uchar * result);
 * 
 * Return a newly allocated 41-byte 0-terminated ascii string
 * containing a hexadecimal version of the 20-byte binary sha1 sum
 * pointed to by `result'.
 */
t_uchar *
sha1_alloc_ascii (alloc_limits limits, t_uchar * result)
{
  t_uchar * answer = 0;

  answer = lim_malloc (limits, 41);
  if (!answer)
    return 0;

  answer[40] = 0;

  sha1_ascii (answer, result);

  return answer;
}


/*(c sha1_ascii)
 * void sha1_ascii (t_uchar * answer, t_uchar * result);
 * 
 * Format a 40-byte ascii string containing a hexadecimal version of
 * the 20-byte binary SHA1 sum pointed to by `result'.
 * 
 * This function does not add a final 0-byte to the string.
 */
void
sha1_ascii (t_uchar * answer, t_uchar * result)
{
  int x;

  for (x = 0; x < 20; ++x)
    {
      int hi = (0xf & (result[x] >> 4));
      int lo = (0xf & result[x]);

      answer[2 * x] = ((hi >= 10) ? ('a' + (hi - 10)) : ('0' + hi));
      answer[2 * x + 1] = ((lo >= 10) ? ('a' + (lo - 10)) : ('0' + lo));
    }
}

/**
 * \brief Format a 40-byte ascii string containing a hexadecimal version of
 * the 20-byte binary SHA1 sum pointed to by `sha1'.
 * 
 * This function does not add a final 0-byte to the string.
 */
void
sha1_to_ascii (t_uchar * answer, sha1_t * sha1)
{
  sha1_ascii (answer, (t_uchar *) sha1);
}

/**
 * \brief convert a hex representation of a sha1 to a sha1_t
 * \param out the sha1 to populate
 * \return zero on success;
 */
int
sha1_from_ascii (sha1_t * out, t_uchar const * ascii)
{
  unsigned int scanresult;
  t_uchar const * position = ascii;
  t_uchar *current = (t_uchar *)out;
  int count;
  out->A = 0;
  out->B = 0;
  out->C = 0;
  out->D = 0;
  out->E = 0;
  if (str_length (ascii) != 40)
    return -1;

  for (count =0; count < 20; ++count)
    {
      int ign;
      if (cvt_hex_to_uint (&ign, &scanresult, position, 2))
	  return -1;
      position +=2;
      current[count] = scanresult;
    }
  return 0;
}



/* --- Code below is the primary difference between md5.c and sha.c --- */

/* SHA1 round constants */
#define K1 0x5a827999L
#define K2 0x6ed9eba1L
#define K3 0x8f1bbcdcL
#define K4 0xca62c1d6L

/* Round functions.  Note that F2 is the same as F4.  */
#define F1(B,C,D) ( D ^ ( B & ( C ^ D ) ) )
#define F2(B,C,D) (B ^ C ^ D)
#define F3(B,C,D) ( ( B & C ) | ( D & ( B | C ) ) )
#define F4(B,C,D) (B ^ C ^ D)

/* Process LEN bytes of BUFFER, accumulating context into CTX.
   It is assumed that LEN % 64 == 0.
   Most of this code comes from GnuPG's cipher/sha1.c.  */
static void
sha1_process_blocks (const t_uchar *buffer, size_t len, sha1_context_t ctx)
{
  const t_uint32 *words = buffer;
  size_t nwords = len / sizeof (t_uint32);
  const t_uint32 *endp = words + nwords;
  t_uint32 x[16];
  t_uint32 a = ctx->current_sha1.A;
  t_uint32 b = ctx->current_sha1.B;
  t_uint32 c = ctx->current_sha1.C;
  t_uint32 d = ctx->current_sha1.D;
  t_uint32 e = ctx->current_sha1.E;

  /* First increment the byte count.  RFC 1321 specifies the possible
     length of the file up to 2^64 bits.  Here we only compute the
     number of bytes.  Do a double word increment.  */
  ctx->total[0] += len;
  if (ctx->total[0] < len)
    ++ctx->total[1];

#define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
#define M(I) ( tm =   x[I&0x0f] ^ x[(I-14)&0x0f] \
		    ^ x[(I-8)&0x0f] ^ x[(I-3)&0x0f] \
	       , (x[I&0x0f] = rol(tm, 1)) )

#define R(A,B,C,D,E,F,K,M)  do { E += rol( A, 5 )     \
				      + F( B, C, D )  \
				      + K	      \
				      + M;	      \
				 B = rol( B, 30 );    \
			       } while(0)

  while (words < endp)
    {
      t_uint32 tm;
      int t;
      /* FIXME: see sha1.c for a better implementation.  */
      for (t = 0; t < 16; t++)
	{
	  x[t] = NOTSWAP (*words);
	  words++;
	}

      R( a, b, c, d, e, F1, K1, x[ 0] );
      R( e, a, b, c, d, F1, K1, x[ 1] );
      R( d, e, a, b, c, F1, K1, x[ 2] );
      R( c, d, e, a, b, F1, K1, x[ 3] );
      R( b, c, d, e, a, F1, K1, x[ 4] );
      R( a, b, c, d, e, F1, K1, x[ 5] );
      R( e, a, b, c, d, F1, K1, x[ 6] );
      R( d, e, a, b, c, F1, K1, x[ 7] );
      R( c, d, e, a, b, F1, K1, x[ 8] );
      R( b, c, d, e, a, F1, K1, x[ 9] );
      R( a, b, c, d, e, F1, K1, x[10] );
      R( e, a, b, c, d, F1, K1, x[11] );
      R( d, e, a, b, c, F1, K1, x[12] );
      R( c, d, e, a, b, F1, K1, x[13] );
      R( b, c, d, e, a, F1, K1, x[14] );
      R( a, b, c, d, e, F1, K1, x[15] );
      R( e, a, b, c, d, F1, K1, M(16) );
      R( d, e, a, b, c, F1, K1, M(17) );
      R( c, d, e, a, b, F1, K1, M(18) );
      R( b, c, d, e, a, F1, K1, M(19) );
      R( a, b, c, d, e, F2, K2, M(20) );
      R( e, a, b, c, d, F2, K2, M(21) );
      R( d, e, a, b, c, F2, K2, M(22) );
      R( c, d, e, a, b, F2, K2, M(23) );
      R( b, c, d, e, a, F2, K2, M(24) );
      R( a, b, c, d, e, F2, K2, M(25) );
      R( e, a, b, c, d, F2, K2, M(26) );
      R( d, e, a, b, c, F2, K2, M(27) );
      R( c, d, e, a, b, F2, K2, M(28) );
      R( b, c, d, e, a, F2, K2, M(29) );
      R( a, b, c, d, e, F2, K2, M(30) );
      R( e, a, b, c, d, F2, K2, M(31) );
      R( d, e, a, b, c, F2, K2, M(32) );
      R( c, d, e, a, b, F2, K2, M(33) );
      R( b, c, d, e, a, F2, K2, M(34) );
      R( a, b, c, d, e, F2, K2, M(35) );
      R( e, a, b, c, d, F2, K2, M(36) );
      R( d, e, a, b, c, F2, K2, M(37) );
      R( c, d, e, a, b, F2, K2, M(38) );
      R( b, c, d, e, a, F2, K2, M(39) );
      R( a, b, c, d, e, F3, K3, M(40) );
      R( e, a, b, c, d, F3, K3, M(41) );
      R( d, e, a, b, c, F3, K3, M(42) );
      R( c, d, e, a, b, F3, K3, M(43) );
      R( b, c, d, e, a, F3, K3, M(44) );
      R( a, b, c, d, e, F3, K3, M(45) );
      R( e, a, b, c, d, F3, K3, M(46) );
      R( d, e, a, b, c, F3, K3, M(47) );
      R( c, d, e, a, b, F3, K3, M(48) );
      R( b, c, d, e, a, F3, K3, M(49) );
      R( a, b, c, d, e, F3, K3, M(50) );
      R( e, a, b, c, d, F3, K3, M(51) );
      R( d, e, a, b, c, F3, K3, M(52) );
      R( c, d, e, a, b, F3, K3, M(53) );
      R( b, c, d, e, a, F3, K3, M(54) );
      R( a, b, c, d, e, F3, K3, M(55) );
      R( e, a, b, c, d, F3, K3, M(56) );
      R( d, e, a, b, c, F3, K3, M(57) );
      R( c, d, e, a, b, F3, K3, M(58) );
      R( b, c, d, e, a, F3, K3, M(59) );
      R( a, b, c, d, e, F4, K4, M(60) );
      R( e, a, b, c, d, F4, K4, M(61) );
      R( d, e, a, b, c, F4, K4, M(62) );
      R( c, d, e, a, b, F4, K4, M(63) );
      R( b, c, d, e, a, F4, K4, M(64) );
      R( a, b, c, d, e, F4, K4, M(65) );
      R( e, a, b, c, d, F4, K4, M(66) );
      R( d, e, a, b, c, F4, K4, M(67) );
      R( c, d, e, a, b, F4, K4, M(68) );
      R( b, c, d, e, a, F4, K4, M(69) );
      R( a, b, c, d, e, F4, K4, M(70) );
      R( e, a, b, c, d, F4, K4, M(71) );
      R( d, e, a, b, c, F4, K4, M(72) );
      R( c, d, e, a, b, F4, K4, M(73) );
      R( b, c, d, e, a, F4, K4, M(74) );
      R( a, b, c, d, e, F4, K4, M(75) );
      R( e, a, b, c, d, F4, K4, M(76) );
      R( d, e, a, b, c, F4, K4, M(77) );
      R( c, d, e, a, b, F4, K4, M(78) );
      R( b, c, d, e, a, F4, K4, M(79) );

      a = ctx->current_sha1.A += a;
      b = ctx->current_sha1.B += b;
      c = ctx->current_sha1.C += c;
      d = ctx->current_sha1.D += d;
      e = ctx->current_sha1.E += e;
    }
}

/* tag: Colin Walters Mon, 05 Jan 2004 18:22:29 -0500 (sha1.c)
 */