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- Committer: Bazaar Package Importer
- Author(s): Tomas Fasth
- Date: 2005-05-24 13:31:34 UTC
- mfrom: (1.1.1 upstream)
- Revision ID: james.westby@ubuntu.com-20050524133134-6hn24gprfmo91sfv
Tags: 1.4.1-1
New upstream release.
- files added:
- Makefile.in
- files removed:
- ChangeLog
- crypto
- files modified:
- README
- doc/keymap-names.txt *
added
removed
crypto/bn_lib.c
1
/* crypto/bn/bn_lib.c */
2
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3
* All rights reserved.
4
*
5
* This package is an SSL implementation written
6
* by Eric Young (eay@cryptsoft.com).
7
* The implementation was written so as to conform with Netscapes SSL.
8
*
9
* This library is free for commercial and non-commercial use as long as
10
* the following conditions are aheared to. The following conditions
11
* apply to all code found in this distribution, be it the RC4, RSA,
12
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
13
* included with this distribution is covered by the same copyright terms
14
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
15
*
16
* Copyright remains Eric Young's, and as such any Copyright notices in
17
* the code are not to be removed.
18
* If this package is used in a product, Eric Young should be given attribution
19
* as the author of the parts of the library used.
20
* This can be in the form of a textual message at program startup or
21
* in documentation (online or textual) provided with the package.
22
*
23
* Redistribution and use in source and binary forms, with or without
24
* modification, are permitted provided that the following conditions
25
* are met:
26
* 1. Redistributions of source code must retain the copyright
27
* notice, this list of conditions and the following disclaimer.
28
* 2. Redistributions in binary form must reproduce the above copyright
29
* notice, this list of conditions and the following disclaimer in the
30
* documentation and/or other materials provided with the distribution.
31
* 3. All advertising materials mentioning features or use of this software
32
* must display the following acknowledgement:
33
* "This product includes cryptographic software written by
34
* Eric Young (eay@cryptsoft.com)"
35
* The word 'cryptographic' can be left out if the rouines from the library
36
* being used are not cryptographic related :-).
37
* 4. If you include any Windows specific code (or a derivative thereof) from
38
* the apps directory (application code) you must include an acknowledgement:
39
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40
*
41
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51
* SUCH DAMAGE.
52
*
53
* The licence and distribution terms for any publically available version or
54
* derivative of this code cannot be changed. i.e. this code cannot simply be
55
* copied and put under another distribution licence
56
* [including the GNU Public Licence.]
57
*/
58
59
#ifndef BN_DEBUG
60
# undef NDEBUG /* avoid conflicting definitions */
61
# define NDEBUG
62
#endif
63
64
#include <assert.h>
65
#include <limits.h>
66
#include <stdio.h>
67
#include "bn_lcl.h"
68
69
#if 0
70
BIGNUM *BN_value_one(void)
71
{
72
static BN_ULONG data_one=1L;
73
static BIGNUM const_one={&data_one,1,1,0};
74
75
return(&const_one);
76
}
77
#endif
78
79
int BN_num_bits_word(BN_ULONG l)
80
{
81
static const char bits[256]={
82
0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,
83
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
84
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
85
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
86
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
87
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
88
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
89
7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
90
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
91
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
92
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
93
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
94
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
95
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
96
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
97
8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
98
};
99
100
#if defined(SIXTY_FOUR_BIT_LONG)
101
if (l & 0xffffffff00000000L)
102
{
103
if (l & 0xffff000000000000L)
104
{
105
if (l & 0xff00000000000000L)
106
{
107
return(bits[(int)(l>>56)]+56);
108
}
109
else return(bits[(int)(l>>48)]+48);
110
}
111
else
112
{
113
if (l & 0x0000ff0000000000L)
114
{
115
return(bits[(int)(l>>40)]+40);
116
}
117
else return(bits[(int)(l>>32)]+32);
118
}
119
}
120
else
121
#else
122
#ifdef SIXTY_FOUR_BIT
123
if (l & 0xffffffff00000000LL)
124
{
125
if (l & 0xffff000000000000LL)
126
{
127
if (l & 0xff00000000000000LL)
128
{
129
return(bits[(int)(l>>56)]+56);
130
}
131
else return(bits[(int)(l>>48)]+48);
132
}
133
else
134
{
135
if (l & 0x0000ff0000000000LL)
136
{
137
return(bits[(int)(l>>40)]+40);
138
}
139
else return(bits[(int)(l>>32)]+32);
140
}
141
}
142
else
143
#endif
144
#endif
145
{
146
#if defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
147
if (l & 0xffff0000L)
148
{
149
if (l & 0xff000000L)
150
return(bits[(int)(l>>24L)]+24);
151
else return(bits[(int)(l>>16L)]+16);
152
}
153
else
154
#endif
155
{
156
#if defined(SIXTEEN_BIT) || defined(THIRTY_TWO_BIT) || defined(SIXTY_FOUR_BIT) || defined(SIXTY_FOUR_BIT_LONG)
157
if (l & 0xff00L)
158
return(bits[(int)(l>>8)]+8);
159
else
160
#endif
161
return(bits[(int)(l )] );
162
}
163
}
164
}
165
166
int BN_num_bits(const BIGNUM *a)
167
{
168
BN_ULONG l;
169
int i;
170
171
bn_check_top(a);
172
173
if (a->top == 0) return(0);
174
l=a->d[a->top-1];
175
assert(l != 0);
176
i=(a->top-1)*BN_BITS2;
177
return(i+BN_num_bits_word(l));
178
}
179
180
void BN_clear_free(BIGNUM *a)
181
{
182
int i;
183
184
if (a == NULL) return;
185
if (a->d != NULL)
186
{
187
memset(a->d,0,a->dmax*sizeof(a->d[0]));
188
if (!(BN_get_flags(a,BN_FLG_STATIC_DATA)))
189
OPENSSL_free(a->d);
190
}
191
i=BN_get_flags(a,BN_FLG_MALLOCED);
192
memset(a,0,sizeof(BIGNUM));
193
if (i)
194
OPENSSL_free(a);
195
}
196
197
void BN_free(BIGNUM *a)
198
{
199
if (a == NULL) return;
200
if ((a->d != NULL) && !(BN_get_flags(a,BN_FLG_STATIC_DATA)))
201
OPENSSL_free(a->d);
202
a->flags|=BN_FLG_FREE; /* REMOVE? */
203
if (a->flags & BN_FLG_MALLOCED)
204
OPENSSL_free(a);
205
}
206
207
void BN_init(BIGNUM *a)
208
{
209
memset(a,0,sizeof(BIGNUM));
210
}
211
212
#if 0
213
BIGNUM *BN_new(void)
214
{
215
BIGNUM *ret;
216
217
if ((ret=(BIGNUM *)OPENSSL_malloc(sizeof(BIGNUM))) == NULL)
218
{
219
BNerr(BN_F_BN_NEW,ERR_R_MALLOC_FAILURE);
220
return(NULL);
221
}
222
ret->flags=BN_FLG_MALLOCED;
223
ret->top=0;
224
ret->neg=0;
225
ret->dmax=0;
226
ret->d=NULL;
227
return(ret);
228
}
229
#endif
230
231
/* This is an internal function that should not be used in applications.
232
* It ensures that 'b' has enough room for a 'words' word number number.
233
* It is mostly used by the various BIGNUM routines. If there is an error,
234
* NULL is returned. If not, 'b' is returned. */
235
236
BIGNUM *bn_expand2(BIGNUM *b, int words)
237
{
238
BN_ULONG *A,*a;
239
const BN_ULONG *B;
240
int i;
241
242
bn_check_top(b);
243
244
if (words > b->dmax)
245
{
246
if (words > (INT_MAX/(4*BN_BITS2)))
247
{
248
BNerr(BN_F_BN_EXPAND2,BN_R_BIGNUM_TOO_LONG);
249
return NULL;
250
}
251
252
bn_check_top(b);
253
if (BN_get_flags(b,BN_FLG_STATIC_DATA))
254
{
255
BNerr(BN_F_BN_EXPAND2,BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);
256
return(NULL);
257
}
258
a=A=(BN_ULONG *)OPENSSL_malloc(sizeof(BN_ULONG)*(words+1));
259
if (A == NULL)
260
{
261
BNerr(BN_F_BN_EXPAND2,ERR_R_MALLOC_FAILURE);
262
return(NULL);
263
}
264
#if 1
265
B=b->d;
266
/* Check if the previous number needs to be copied */
267
if (B != NULL)
268
{
269
#if 0
270
/* This lot is an unrolled loop to copy b->top
271
* BN_ULONGs from B to A
272
*/
273
/*
274
* I have nothing against unrolling but it's usually done for
275
* several reasons, namely:
276
* - minimize percentage of decision making code, i.e. branches;
277
* - avoid cache trashing;
278
* - make it possible to schedule loads earlier;
279
* Now let's examine the code below. The cornerstone of C is
280
* "programmer is always right" and that's what we love it for:-)
281
* For this very reason C compilers have to be paranoid when it
282
* comes to data aliasing and assume the worst. Yeah, but what
283
* does it mean in real life? This means that loop body below will
284
* be compiled to sequence of loads immediately followed by stores
285
* as compiler assumes the worst, something in A==B+1 style. As a
286
* result CPU pipeline is going to starve for incoming data. Secondly
287
* if A and B happen to share same cache line such code is going to
288
* cause severe cache trashing. Both factors have severe impact on
289
* performance of modern CPUs and this is the reason why this
290
* particular piece of code is #ifdefed away and replaced by more
291
* "friendly" version found in #else section below. This comment
292
* also applies to BN_copy function.
293
*
294
* <appro@fy.chalmers.se>
295
*/
296
for (i=b->top&(~7); i>0; i-=8)
297
{
298
A[0]=B[0]; A[1]=B[1]; A[2]=B[2]; A[3]=B[3];
299
A[4]=B[4]; A[5]=B[5]; A[6]=B[6]; A[7]=B[7];
300
A+=8;
301
B+=8;
302
}
303
switch (b->top&7)
304
{
305
case 7:
306
A[6]=B[6];
307
case 6:
308
A[5]=B[5];
309
case 5:
310
A[4]=B[4];
311
case 4:
312
A[3]=B[3];
313
case 3:
314
A[2]=B[2];
315
case 2:
316
A[1]=B[1];
317
case 1:
318
A[0]=B[0];
319
case 0:
320
/* I need the 'case 0' entry for utrix cc.
321
* If the optimizer is turned on, it does the
322
* switch table by doing
323
* a=top&7
324
* a--;
325
* goto jump_table[a];
326
* If top is 0, this makes us jump to 0xffffffc
327
* which is rather bad :-(.
328
* eric 23-Apr-1998
329
*/
330
;
331
}
332
#else
333
for (i=b->top>>2; i>0; i--,A+=4,B+=4)
334
{
335
/*
336
* The fact that the loop is unrolled
337
* 4-wise is a tribute to Intel. It's
338
* the one that doesn't have enough
339
* registers to accomodate more data.
340
* I'd unroll it 8-wise otherwise:-)
341
*
342
* <appro@fy.chalmers.se>
343
*/
344
BN_ULONG a0,a1,a2,a3;
345
a0=B[0]; a1=B[1]; a2=B[2]; a3=B[3];
346
A[0]=a0; A[1]=a1; A[2]=a2; A[3]=a3;
347
}
348
switch (b->top&3)
349
{
350
case 3: A[2]=B[2];
351
case 2: A[1]=B[1];
352
case 1: A[0]=B[0];
353
case 0: ; /* ultrix cc workaround, see above */
354
}
355
#endif
356
OPENSSL_free(b->d);
357
}
358
359
b->d=a;
360
b->dmax=words;
361
362
/* Now need to zero any data between b->top and b->max */
363
364
A= &(b->d[b->top]);
365
for (i=(b->dmax - b->top)>>3; i>0; i--,A+=8)
366
{
367
A[0]=0; A[1]=0; A[2]=0; A[3]=0;
368
A[4]=0; A[5]=0; A[6]=0; A[7]=0;
369
}
370
for (i=(b->dmax - b->top)&7; i>0; i--,A++)
371
A[0]=0;
372
#else
373
memset(A,0,sizeof(BN_ULONG)*(words+1));
374
memcpy(A,b->d,sizeof(b->d[0])*b->top);
375
b->d=a;
376
b->max=words;
377
#endif
378
379
/* memset(&(p[b->max]),0,((words+1)-b->max)*sizeof(BN_ULONG)); */
380
/* { int i; for (i=b->max; i<words+1; i++) p[i]=i;} */
381
382
}
383
return(b);
384
}
385
386
#if 0
387
BIGNUM *BN_dup(const BIGNUM *a)
388
{
389
BIGNUM *r;
390
391
if (a == NULL) return NULL;
392
393
bn_check_top(a);
394
395
r=BN_new();
396
if (r == NULL) return(NULL);
397
return((BIGNUM *)BN_copy(r,a));
398
}
399
#endif
400
401
BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b)
402
{
403
int i;
404
BN_ULONG *A;
405
const BN_ULONG *B;
406
407
bn_check_top(b);
408
409
if (a == b) return(a);
410
if (bn_wexpand(a,b->top) == NULL) return(NULL);
411
412
#if 1
413
A=a->d;
414
B=b->d;
415
for (i=b->top>>2; i>0; i--,A+=4,B+=4)
416
{
417
BN_ULONG a0,a1,a2,a3;
418
a0=B[0]; a1=B[1]; a2=B[2]; a3=B[3];
419
A[0]=a0; A[1]=a1; A[2]=a2; A[3]=a3;
420
}
421
switch (b->top&3)
422
{
423
case 3: A[2]=B[2];
424
case 2: A[1]=B[1];
425
case 1: A[0]=B[0];
426
case 0: ; /* ultrix cc workaround, see comments in bn_expand2 */
427
}
428
#else
429
memcpy(a->d,b->d,sizeof(b->d[0])*b->top);
430
#endif
431
432
/* memset(&(a->d[b->top]),0,sizeof(a->d[0])*(a->max-b->top));*/
433
a->top=b->top;
434
if ((a->top == 0) && (a->d != NULL))
435
a->d[0]=0;
436
a->neg=b->neg;
437
return(a);
438
}
439
440
#if 0
441
void BN_clear(BIGNUM *a)
442
{
443
if (a->d != NULL)
444
memset(a->d,0,a->dmax*sizeof(a->d[0]));
445
a->top=0;
446
a->neg=0;
447
}
448
449
BN_ULONG BN_get_word(BIGNUM *a)
450
{
451
int i,n;
452
BN_ULONG ret=0;
453
454
n=BN_num_bytes(a);
455
if (n > sizeof(BN_ULONG))
456
return(BN_MASK2);
457
for (i=a->top-1; i>=0; i--)
458
{
459
#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
460
ret<<=BN_BITS4; /* stops the compiler complaining */
461
ret<<=BN_BITS4;
462
#else
463
ret=0;
464
#endif
465
ret|=a->d[i];
466
}
467
return(ret);
468
}
469
#endif
470
471
int BN_set_word(BIGNUM *a, BN_ULONG w)
472
{
473
int i,n;
474
if (bn_expand(a,sizeof(BN_ULONG)*8) == NULL) return(0);
475
476
n=sizeof(BN_ULONG)/BN_BYTES;
477
a->neg=0;
478
a->top=0;
479
a->d[0]=(BN_ULONG)w&BN_MASK2;
480
if (a->d[0] != 0) a->top=1;
481
for (i=1; i<n; i++)
482
{
483
/* the following is done instead of
484
* w>>=BN_BITS2 so compilers don't complain
485
* on builds where sizeof(long) == BN_TYPES */
486
#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
487
w>>=BN_BITS4;
488
w>>=BN_BITS4;
489
#else
490
w=0;
491
#endif
492
a->d[i]=(BN_ULONG)w&BN_MASK2;
493
if (a->d[i] != 0) a->top=i+1;
494
}
495
return(1);
496
}
497
498
/* ignore negative */
499
BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret)
500
{
501
unsigned int i,m;
502
unsigned int n;
503
BN_ULONG l;
504
505
#if 0
506
if (ret == NULL) ret=BN_new();
507
#endif
508
if (ret == NULL) return(NULL);
509
l=0;
510
n=len;
511
if (n == 0)
512
{
513
ret->top=0;
514
return(ret);
515
}
516
if (bn_expand(ret,(int)(n+2)*8) == NULL)
517
return(NULL);
518
i=((n-1)/BN_BYTES)+1;
519
m=((n-1)%(BN_BYTES));
520
ret->top=i;
521
while (n-- > 0)
522
{
523
l=(l<<8L)| *(s++);
524
if (m-- == 0)
525
{
526
ret->d[--i]=l;
527
l=0;
528
m=BN_BYTES-1;
529
}
530
}
531
/* need to call this due to clear byte at top if avoiding
532
* having the top bit set (-ve number) */
533
bn_fix_top(ret);
534
return(ret);
535
}
536
537
/* ignore negative */
538
int BN_bn2bin(const BIGNUM *a, unsigned char *to)
539
{
540
int n,i;
541
BN_ULONG l;
542
543
n=i=BN_num_bytes(a);
544
while (i-- > 0)
545
{
546
l=a->d[i/BN_BYTES];
547
*(to++)=(unsigned char)(l>>(8*(i%BN_BYTES)))&0xff;
548
}
549
return(n);
550
}
551
552
int BN_ucmp(const BIGNUM *a, const BIGNUM *b)
553
{
554
int i;
555
BN_ULONG t1,t2,*ap,*bp;
556
557
bn_check_top(a);
558
bn_check_top(b);
559
560
i=a->top-b->top;
561
if (i != 0) return(i);
562
ap=a->d;
563
bp=b->d;
564
for (i=a->top-1; i>=0; i--)
565
{
566
t1= ap[i];
567
t2= bp[i];
568
if (t1 != t2)
569
return(t1 > t2?1:-1);
570
}
571
return(0);
572
}
573
574
#if 0
575
int BN_cmp(const BIGNUM *a, const BIGNUM *b)
576
{
577
int i;
578
int gt,lt;
579
BN_ULONG t1,t2;
580
581
if ((a == NULL) || (b == NULL))
582
{
583
if (a != NULL)
584
return(-1);
585
else if (b != NULL)
586
return(1);
587
else
588
return(0);
589
}
590
591
bn_check_top(a);
592
bn_check_top(b);
593
594
if (a->neg != b->neg)
595
{
596
if (a->neg)
597
return(-1);
598
else return(1);
599
}
600
if (a->neg == 0)
601
{ gt=1; lt= -1; }
602
else { gt= -1; lt=1; }
603
604
if (a->top > b->top) return(gt);
605
if (a->top < b->top) return(lt);
606
for (i=a->top-1; i>=0; i--)
607
{
608
t1=a->d[i];
609
t2=b->d[i];
610
if (t1 > t2) return(gt);
611
if (t1 < t2) return(lt);
612
}
613
return(0);
614
}
615
616
int BN_set_bit(BIGNUM *a, int n)
617
{
618
int i,j,k;
619
620
i=n/BN_BITS2;
621
j=n%BN_BITS2;
622
if (a->top <= i)
623
{
624
if (bn_wexpand(a,i+1) == NULL) return(0);
625
for(k=a->top; k<i+1; k++)
626
a->d[k]=0;
627
a->top=i+1;
628
}
629
630
a->d[i]|=(((BN_ULONG)1)<<j);
631
return(1);
632
}
633
634
int BN_clear_bit(BIGNUM *a, int n)
635
{
636
int i,j;
637
638
i=n/BN_BITS2;
639
j=n%BN_BITS2;
640
if (a->top <= i) return(0);
641
642
a->d[i]&=(~(((BN_ULONG)1)<<j));
643
bn_fix_top(a);
644
return(1);
645
}
646
#endif
647
648
int BN_is_bit_set(const BIGNUM *a, int n)
649
{
650
int i,j;
651
652
if (n < 0) return(0);
653
i=n/BN_BITS2;
654
j=n%BN_BITS2;
655
if (a->top <= i) return(0);
656
return((a->d[i]&(((BN_ULONG)1)<<j))?1:0);
657
}
658
659
#if 0
660
int BN_mask_bits(BIGNUM *a, int n)
661
{
662
int b,w;
663
664
w=n/BN_BITS2;
665
b=n%BN_BITS2;
666
if (w >= a->top) return(0);
667
if (b == 0)
668
a->top=w;
669
else
670
{
671
a->top=w+1;
672
a->d[w]&= ~(BN_MASK2<<b);
673
}
674
bn_fix_top(a);
675
return(1);
676
}
677
678
int bn_cmp_words(BN_ULONG *a, BN_ULONG *b, int n)
679
{
680
int i;
681
BN_ULONG aa,bb;
682
683
aa=a[n-1];
684
bb=b[n-1];
685
if (aa != bb) return((aa > bb)?1:-1);
686
for (i=n-2; i>=0; i--)
687
{
688
aa=a[i];
689
bb=b[i];
690
if (aa != bb) return((aa > bb)?1:-1);
691
}
692
return(0);
693
}
694
#endif
Loggerhead is a web-based interface for Breezy
Version: 2.0.1