Fix for CVE-2014-3570 (with minor bn_asm.c revamp).
[openssl.git] / crypto / bn / bn_asm.c
1 /* crypto/bn/bn_asm.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 <openssl/crypto.h>
66 #include "cryptlib.h"
67 #include "bn_lcl.h"
68
69 #if defined(BN_LLONG) || defined(BN_UMULT_HIGH)
70
71 BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
72         {
73         BN_ULONG c1=0;
74
75         assert(num >= 0);
76         if (num <= 0) return(c1);
77
78 #ifndef OPENSSL_SMALL_FOOTPRINT
79         while (num&~3)
80                 {
81                 mul_add(rp[0],ap[0],w,c1);
82                 mul_add(rp[1],ap[1],w,c1);
83                 mul_add(rp[2],ap[2],w,c1);
84                 mul_add(rp[3],ap[3],w,c1);
85                 ap+=4; rp+=4; num-=4;
86                 }
87 #endif
88         while (num)
89                 {
90                 mul_add(rp[0],ap[0],w,c1);
91                 ap++; rp++; num--;
92                 }
93         
94         return(c1);
95         } 
96
97 BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
98         {
99         BN_ULONG c1=0;
100
101         assert(num >= 0);
102         if (num <= 0) return(c1);
103
104 #ifndef OPENSSL_SMALL_FOOTPRINT
105         while (num&~3)
106                 {
107                 mul(rp[0],ap[0],w,c1);
108                 mul(rp[1],ap[1],w,c1);
109                 mul(rp[2],ap[2],w,c1);
110                 mul(rp[3],ap[3],w,c1);
111                 ap+=4; rp+=4; num-=4;
112                 }
113 #endif
114         while (num)
115                 {
116                 mul(rp[0],ap[0],w,c1);
117                 ap++; rp++; num--;
118                 }
119         return(c1);
120         } 
121
122 void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
123         {
124         assert(n >= 0);
125         if (n <= 0) return;
126
127 #ifndef OPENSSL_SMALL_FOOTPRINT
128         while (n&~3)
129                 {
130                 sqr(r[0],r[1],a[0]);
131                 sqr(r[2],r[3],a[1]);
132                 sqr(r[4],r[5],a[2]);
133                 sqr(r[6],r[7],a[3]);
134                 a+=4; r+=8; n-=4;
135                 }
136 #endif
137         while (n)
138                 {
139                 sqr(r[0],r[1],a[0]);
140                 a++; r+=2; n--;
141                 }
142         }
143
144 #else /* !(defined(BN_LLONG) || defined(BN_UMULT_HIGH)) */
145
146 BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
147         {
148         BN_ULONG c=0;
149         BN_ULONG bl,bh;
150
151         assert(num >= 0);
152         if (num <= 0) return((BN_ULONG)0);
153
154         bl=LBITS(w);
155         bh=HBITS(w);
156
157 #ifndef OPENSSL_SMALL_FOOTPRINT
158         while (num&~3)
159                 {
160                 mul_add(rp[0],ap[0],bl,bh,c);
161                 mul_add(rp[1],ap[1],bl,bh,c);
162                 mul_add(rp[2],ap[2],bl,bh,c);
163                 mul_add(rp[3],ap[3],bl,bh,c);
164                 ap+=4; rp+=4; num-=4;
165                 }
166 #endif
167         while (num)
168                 {
169                 mul_add(rp[0],ap[0],bl,bh,c);
170                 ap++; rp++; num--;
171                 }
172         return(c);
173         } 
174
175 BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w)
176         {
177         BN_ULONG carry=0;
178         BN_ULONG bl,bh;
179
180         assert(num >= 0);
181         if (num <= 0) return((BN_ULONG)0);
182
183         bl=LBITS(w);
184         bh=HBITS(w);
185
186 #ifndef OPENSSL_SMALL_FOOTPRINT
187         while (num&~3)
188                 {
189                 mul(rp[0],ap[0],bl,bh,carry);
190                 mul(rp[1],ap[1],bl,bh,carry);
191                 mul(rp[2],ap[2],bl,bh,carry);
192                 mul(rp[3],ap[3],bl,bh,carry);
193                 ap+=4; rp+=4; num-=4;
194                 }
195 #endif
196         while (num)
197                 {
198                 mul(rp[0],ap[0],bl,bh,carry);
199                 ap++; rp++; num--;
200                 }
201         return(carry);
202         } 
203
204 void bn_sqr_words(BN_ULONG *r, const BN_ULONG *a, int n)
205         {
206         assert(n >= 0);
207         if (n <= 0) return;
208
209 #ifndef OPENSSL_SMALL_FOOTPRINT
210         while (n&~3)
211                 {
212                 sqr64(r[0],r[1],a[0]);
213                 sqr64(r[2],r[3],a[1]);
214                 sqr64(r[4],r[5],a[2]);
215                 sqr64(r[6],r[7],a[3]);
216                 a+=4; r+=8; n-=4;
217                 }
218 #endif
219         while (n)
220                 {
221                 sqr64(r[0],r[1],a[0]);
222                 a++; r+=2; n--;
223                 }
224         }
225
226 #endif /* !(defined(BN_LLONG) || defined(BN_UMULT_HIGH)) */
227
228 #if defined(BN_LLONG) && defined(BN_DIV2W)
229
230 BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
231         {
232         return((BN_ULONG)(((((BN_ULLONG)h)<<BN_BITS2)|l)/(BN_ULLONG)d));
233         }
234
235 #else
236
237 /* Divide h,l by d and return the result. */
238 /* I need to test this some more :-( */
239 BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d)
240         {
241         BN_ULONG dh,dl,q,ret=0,th,tl,t;
242         int i,count=2;
243
244         if (d == 0) return(BN_MASK2);
245
246         i=BN_num_bits_word(d);
247         assert((i == BN_BITS2) || (h <= (BN_ULONG)1<<i));
248
249         i=BN_BITS2-i;
250         if (h >= d) h-=d;
251
252         if (i)
253                 {
254                 d<<=i;
255                 h=(h<<i)|(l>>(BN_BITS2-i));
256                 l<<=i;
257                 }
258         dh=(d&BN_MASK2h)>>BN_BITS4;
259         dl=(d&BN_MASK2l);
260         for (;;)
261                 {
262                 if ((h>>BN_BITS4) == dh)
263                         q=BN_MASK2l;
264                 else
265                         q=h/dh;
266
267                 th=q*dh;
268                 tl=dl*q;
269                 for (;;)
270                         {
271                         t=h-th;
272                         if ((t&BN_MASK2h) ||
273                                 ((tl) <= (
274                                         (t<<BN_BITS4)|
275                                         ((l&BN_MASK2h)>>BN_BITS4))))
276                                 break;
277                         q--;
278                         th-=dh;
279                         tl-=dl;
280                         }
281                 t=(tl>>BN_BITS4);
282                 tl=(tl<<BN_BITS4)&BN_MASK2h;
283                 th+=t;
284
285                 if (l < tl) th++;
286                 l-=tl;
287                 if (h < th)
288                         {
289                         h+=d;
290                         q--;
291                         }
292                 h-=th;
293
294                 if (--count == 0) break;
295
296                 ret=q<<BN_BITS4;
297                 h=((h<<BN_BITS4)|(l>>BN_BITS4))&BN_MASK2;
298                 l=(l&BN_MASK2l)<<BN_BITS4;
299                 }
300         ret|=q;
301         return(ret);
302         }
303 #endif /* !defined(BN_LLONG) && defined(BN_DIV2W) */
304
305 #ifdef BN_LLONG
306 BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
307         {
308         BN_ULLONG ll=0;
309
310         assert(n >= 0);
311         if (n <= 0) return((BN_ULONG)0);
312
313 #ifndef OPENSSL_SMALL_FOOTPRINT
314         while (n&~3)
315                 {
316                 ll+=(BN_ULLONG)a[0]+b[0];
317                 r[0]=(BN_ULONG)ll&BN_MASK2;
318                 ll>>=BN_BITS2;
319                 ll+=(BN_ULLONG)a[1]+b[1];
320                 r[1]=(BN_ULONG)ll&BN_MASK2;
321                 ll>>=BN_BITS2;
322                 ll+=(BN_ULLONG)a[2]+b[2];
323                 r[2]=(BN_ULONG)ll&BN_MASK2;
324                 ll>>=BN_BITS2;
325                 ll+=(BN_ULLONG)a[3]+b[3];
326                 r[3]=(BN_ULONG)ll&BN_MASK2;
327                 ll>>=BN_BITS2;
328                 a+=4; b+=4; r+=4; n-=4;
329                 }
330 #endif
331         while (n)
332                 {
333                 ll+=(BN_ULLONG)a[0]+b[0];
334                 r[0]=(BN_ULONG)ll&BN_MASK2;
335                 ll>>=BN_BITS2;
336                 a++; b++; r++; n--;
337                 }
338         return((BN_ULONG)ll);
339         }
340 #else /* !BN_LLONG */
341 BN_ULONG bn_add_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
342         {
343         BN_ULONG c,l,t;
344
345         assert(n >= 0);
346         if (n <= 0) return((BN_ULONG)0);
347
348         c=0;
349 #ifndef OPENSSL_SMALL_FOOTPRINT
350         while (n&~3)
351                 {
352                 t=a[0];
353                 t=(t+c)&BN_MASK2;
354                 c=(t < c);
355                 l=(t+b[0])&BN_MASK2;
356                 c+=(l < t);
357                 r[0]=l;
358                 t=a[1];
359                 t=(t+c)&BN_MASK2;
360                 c=(t < c);
361                 l=(t+b[1])&BN_MASK2;
362                 c+=(l < t);
363                 r[1]=l;
364                 t=a[2];
365                 t=(t+c)&BN_MASK2;
366                 c=(t < c);
367                 l=(t+b[2])&BN_MASK2;
368                 c+=(l < t);
369                 r[2]=l;
370                 t=a[3];
371                 t=(t+c)&BN_MASK2;
372                 c=(t < c);
373                 l=(t+b[3])&BN_MASK2;
374                 c+=(l < t);
375                 r[3]=l;
376                 a+=4; b+=4; r+=4; n-=4;
377                 }
378 #endif
379         while(n)
380                 {
381                 t=a[0];
382                 t=(t+c)&BN_MASK2;
383                 c=(t < c);
384                 l=(t+b[0])&BN_MASK2;
385                 c+=(l < t);
386                 r[0]=l;
387                 a++; b++; r++; n--;
388                 }
389         return((BN_ULONG)c);
390         }
391 #endif /* !BN_LLONG */
392
393 BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, int n)
394         {
395         BN_ULONG t1,t2;
396         int c=0;
397
398         assert(n >= 0);
399         if (n <= 0) return((BN_ULONG)0);
400
401 #ifndef OPENSSL_SMALL_FOOTPRINT
402         while (n&~3)
403                 {
404                 t1=a[0]; t2=b[0];
405                 r[0]=(t1-t2-c)&BN_MASK2;
406                 if (t1 != t2) c=(t1 < t2);
407                 t1=a[1]; t2=b[1];
408                 r[1]=(t1-t2-c)&BN_MASK2;
409                 if (t1 != t2) c=(t1 < t2);
410                 t1=a[2]; t2=b[2];
411                 r[2]=(t1-t2-c)&BN_MASK2;
412                 if (t1 != t2) c=(t1 < t2);
413                 t1=a[3]; t2=b[3];
414                 r[3]=(t1-t2-c)&BN_MASK2;
415                 if (t1 != t2) c=(t1 < t2);
416                 a+=4; b+=4; r+=4; n-=4;
417                 }
418 #endif
419         while (n)
420                 {
421                 t1=a[0]; t2=b[0];
422                 r[0]=(t1-t2-c)&BN_MASK2;
423                 if (t1 != t2) c=(t1 < t2);
424                 a++; b++; r++; n--;
425                 }
426         return(c);
427         }
428
429 #if defined(BN_MUL_COMBA) && !defined(OPENSSL_SMALL_FOOTPRINT)
430
431 #undef bn_mul_comba8
432 #undef bn_mul_comba4
433 #undef bn_sqr_comba8
434 #undef bn_sqr_comba4
435
436 /* mul_add_c(a,b,c0,c1,c2)  -- c+=a*b for three word number c=(c2,c1,c0) */
437 /* mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0) */
438 /* sqr_add_c(a,i,c0,c1,c2)  -- c+=a[i]^2 for three word number c=(c2,c1,c0) */
439 /* sqr_add_c2(a,i,c0,c1,c2) -- c+=2*a[i]*a[j] for three word number c=(c2,c1,c0) */
440
441 #ifdef BN_LLONG
442 /*
443  * Keep in mind that additions to multiplication result can not
444  * overflow, because its high half cannot be all-ones.
445  */
446 #define mul_add_c(a,b,c0,c1,c2)         do {    \
447         BN_ULONG hi;                            \
448         BN_ULLONG t = (BN_ULLONG)(a)*(b);       \
449         t += c0;                /* no carry */  \
450         c0 = (BN_ULONG)Lw(t);                   \
451         hi = (BN_ULONG)Hw(t);                   \
452         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
453         } while(0)
454
455 #define mul_add_c2(a,b,c0,c1,c2)        do {    \
456         BN_ULONG hi;                            \
457         BN_ULLONG t = (BN_ULLONG)(a)*(b);       \
458         BN_ULLONG tt = t+c0;    /* no carry */  \
459         c0 = (BN_ULONG)Lw(tt);                  \
460         hi = (BN_ULONG)Hw(tt);                  \
461         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
462         t += c0;                /* no carry */  \
463         c0 = (BN_ULONG)Lw(t);                   \
464         hi = (BN_ULONG)Hw(t);                   \
465         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
466         } while(0)
467
468 #define sqr_add_c(a,i,c0,c1,c2)         do {    \
469         BN_ULONG hi;                            \
470         BN_ULLONG t = (BN_ULLONG)a[i]*a[i];     \
471         t += c0;                /* no carry */  \
472         c0 = (BN_ULONG)Lw(t);                   \
473         hi = (BN_ULONG)Hw(t);                   \
474         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
475         } while(0)
476
477 #define sqr_add_c2(a,i,j,c0,c1,c2) \
478         mul_add_c2((a)[i],(a)[j],c0,c1,c2)
479
480 #elif defined(BN_UMULT_LOHI)
481 /*
482  * Keep in mind that additions to hi can not overflow, because
483  * the high word of a multiplication result cannot be all-ones.
484  */
485 #define mul_add_c(a,b,c0,c1,c2)         do {    \
486         BN_ULONG ta = (a), tb = (b);            \
487         BN_ULONG lo, hi;                        \
488         BN_UMULT_LOHI(lo,hi,ta,tb);             \
489         c0 += lo; hi += (c0<lo)?1:0;            \
490         c1 += hi; c2 += (c1<hi)?1:0;            \
491         } while(0)
492
493 #define mul_add_c2(a,b,c0,c1,c2)        do {    \
494         BN_ULONG ta = (a), tb = (b);            \
495         BN_ULONG lo, hi, tt;                    \
496         BN_UMULT_LOHI(lo,hi,ta,tb);             \
497         c0 += lo; tt = hi+((c0<lo)?1:0);        \
498         c1 += tt; c2 += (c1<tt)?1:0;            \
499         c0 += lo; hi += (c0<lo)?1:0;            \
500         c1 += hi; c2 += (c1<hi)?1:0;            \
501         } while(0)
502
503 #define sqr_add_c(a,i,c0,c1,c2)         do {    \
504         BN_ULONG ta = (a)[i];                   \
505         BN_ULONG lo, hi;                        \
506         BN_UMULT_LOHI(lo,hi,ta,ta);             \
507         c0 += lo; hi += (c0<lo)?1:0;            \
508         c1 += hi; c2 += (c1<hi)?1:0;            \
509         } while(0)
510
511 #define sqr_add_c2(a,i,j,c0,c1,c2)      \
512         mul_add_c2((a)[i],(a)[j],c0,c1,c2)
513
514 #elif defined(BN_UMULT_HIGH)
515 /*
516  * Keep in mind that additions to hi can not overflow, because
517  * the high word of a multiplication result cannot be all-ones.
518  */
519 #define mul_add_c(a,b,c0,c1,c2)         do {    \
520         BN_ULONG ta = (a), tb = (b);            \
521         BN_ULONG lo = ta * tb;                  \
522         BN_ULONG hi = BN_UMULT_HIGH(ta,tb);     \
523         c0 += lo; hi += (c0<lo)?1:0;            \
524         c1 += hi; c2 += (c1<hi)?1:0;            \
525         } while(0)
526
527 #define mul_add_c2(a,b,c0,c1,c2)        do {    \
528         BN_ULONG ta = (a), tb = (b), tt;        \
529         BN_ULONG lo = ta * tb;                  \
530         BN_ULONG hi = BN_UMULT_HIGH(ta,tb);     \
531         c0 += lo; tt = hi + ((c0<lo)?1:0);      \
532         c1 += tt; c2 += (c1<tt)?1:0;            \
533         c0 += lo; hi += (c0<lo)?1:0;            \
534         c1 += hi; c2 += (c1<hi)?1:0;            \
535         } while(0)
536
537 #define sqr_add_c(a,i,c0,c1,c2)         do {    \
538         BN_ULONG ta = (a)[i];                   \
539         BN_ULONG lo = ta * ta;                  \
540         BN_ULONG hi = BN_UMULT_HIGH(ta,ta);     \
541         c0 += lo; hi += (c0<lo)?1:0;            \
542         c1 += hi; c2 += (c1<hi)?1:0;            \
543         } while(0)
544
545 #define sqr_add_c2(a,i,j,c0,c1,c2)      \
546         mul_add_c2((a)[i],(a)[j],c0,c1,c2)
547
548 #else /* !BN_LLONG */
549 /*
550  * Keep in mind that additions to hi can not overflow, because
551  * the high word of a multiplication result cannot be all-ones.
552  */
553 #define mul_add_c(a,b,c0,c1,c2)         do {    \
554         BN_ULONG lo = LBITS(a), hi = HBITS(a);  \
555         BN_ULONG bl = LBITS(b), bh = HBITS(b);  \
556         mul64(lo,hi,bl,bh);                     \
557         c0 = (c0+lo)&BN_MASK2; if (c0<lo) hi++; \
558         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
559         } while(0)
560
561 #define mul_add_c2(a,b,c0,c1,c2)        do {    \
562         BN_ULONG tt;                            \
563         BN_ULONG lo = LBITS(a), hi = HBITS(a);  \
564         BN_ULONG bl = LBITS(b), bh = HBITS(b);  \
565         mul64(lo,hi,bl,bh);                     \
566         tt = hi;                                \
567         c0 = (c0+lo)&BN_MASK2; if (c0<lo) tt++; \
568         c1 = (c1+tt)&BN_MASK2; if (c1<tt) c2++; \
569         c0 = (c0+lo)&BN_MASK2; if (c0<lo) hi++; \
570         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
571         } while(0)
572
573 #define sqr_add_c(a,i,c0,c1,c2)         do {    \
574         BN_ULONG lo, hi;                        \
575         sqr64(lo,hi,(a)[i]);                    \
576         c0 = (c0+lo)&BN_MASK2; if (c0<lo) hi++; \
577         c1 = (c1+hi)&BN_MASK2; if (c1<hi) c2++; \
578         } while(0)
579
580 #define sqr_add_c2(a,i,j,c0,c1,c2) \
581         mul_add_c2((a)[i],(a)[j],c0,c1,c2)
582 #endif /* !BN_LLONG */
583
584 void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
585         {
586         BN_ULONG c1,c2,c3;
587
588         c1=0;
589         c2=0;
590         c3=0;
591         mul_add_c(a[0],b[0],c1,c2,c3);
592         r[0]=c1;
593         c1=0;
594         mul_add_c(a[0],b[1],c2,c3,c1);
595         mul_add_c(a[1],b[0],c2,c3,c1);
596         r[1]=c2;
597         c2=0;
598         mul_add_c(a[2],b[0],c3,c1,c2);
599         mul_add_c(a[1],b[1],c3,c1,c2);
600         mul_add_c(a[0],b[2],c3,c1,c2);
601         r[2]=c3;
602         c3=0;
603         mul_add_c(a[0],b[3],c1,c2,c3);
604         mul_add_c(a[1],b[2],c1,c2,c3);
605         mul_add_c(a[2],b[1],c1,c2,c3);
606         mul_add_c(a[3],b[0],c1,c2,c3);
607         r[3]=c1;
608         c1=0;
609         mul_add_c(a[4],b[0],c2,c3,c1);
610         mul_add_c(a[3],b[1],c2,c3,c1);
611         mul_add_c(a[2],b[2],c2,c3,c1);
612         mul_add_c(a[1],b[3],c2,c3,c1);
613         mul_add_c(a[0],b[4],c2,c3,c1);
614         r[4]=c2;
615         c2=0;
616         mul_add_c(a[0],b[5],c3,c1,c2);
617         mul_add_c(a[1],b[4],c3,c1,c2);
618         mul_add_c(a[2],b[3],c3,c1,c2);
619         mul_add_c(a[3],b[2],c3,c1,c2);
620         mul_add_c(a[4],b[1],c3,c1,c2);
621         mul_add_c(a[5],b[0],c3,c1,c2);
622         r[5]=c3;
623         c3=0;
624         mul_add_c(a[6],b[0],c1,c2,c3);
625         mul_add_c(a[5],b[1],c1,c2,c3);
626         mul_add_c(a[4],b[2],c1,c2,c3);
627         mul_add_c(a[3],b[3],c1,c2,c3);
628         mul_add_c(a[2],b[4],c1,c2,c3);
629         mul_add_c(a[1],b[5],c1,c2,c3);
630         mul_add_c(a[0],b[6],c1,c2,c3);
631         r[6]=c1;
632         c1=0;
633         mul_add_c(a[0],b[7],c2,c3,c1);
634         mul_add_c(a[1],b[6],c2,c3,c1);
635         mul_add_c(a[2],b[5],c2,c3,c1);
636         mul_add_c(a[3],b[4],c2,c3,c1);
637         mul_add_c(a[4],b[3],c2,c3,c1);
638         mul_add_c(a[5],b[2],c2,c3,c1);
639         mul_add_c(a[6],b[1],c2,c3,c1);
640         mul_add_c(a[7],b[0],c2,c3,c1);
641         r[7]=c2;
642         c2=0;
643         mul_add_c(a[7],b[1],c3,c1,c2);
644         mul_add_c(a[6],b[2],c3,c1,c2);
645         mul_add_c(a[5],b[3],c3,c1,c2);
646         mul_add_c(a[4],b[4],c3,c1,c2);
647         mul_add_c(a[3],b[5],c3,c1,c2);
648         mul_add_c(a[2],b[6],c3,c1,c2);
649         mul_add_c(a[1],b[7],c3,c1,c2);
650         r[8]=c3;
651         c3=0;
652         mul_add_c(a[2],b[7],c1,c2,c3);
653         mul_add_c(a[3],b[6],c1,c2,c3);
654         mul_add_c(a[4],b[5],c1,c2,c3);
655         mul_add_c(a[5],b[4],c1,c2,c3);
656         mul_add_c(a[6],b[3],c1,c2,c3);
657         mul_add_c(a[7],b[2],c1,c2,c3);
658         r[9]=c1;
659         c1=0;
660         mul_add_c(a[7],b[3],c2,c3,c1);
661         mul_add_c(a[6],b[4],c2,c3,c1);
662         mul_add_c(a[5],b[5],c2,c3,c1);
663         mul_add_c(a[4],b[6],c2,c3,c1);
664         mul_add_c(a[3],b[7],c2,c3,c1);
665         r[10]=c2;
666         c2=0;
667         mul_add_c(a[4],b[7],c3,c1,c2);
668         mul_add_c(a[5],b[6],c3,c1,c2);
669         mul_add_c(a[6],b[5],c3,c1,c2);
670         mul_add_c(a[7],b[4],c3,c1,c2);
671         r[11]=c3;
672         c3=0;
673         mul_add_c(a[7],b[5],c1,c2,c3);
674         mul_add_c(a[6],b[6],c1,c2,c3);
675         mul_add_c(a[5],b[7],c1,c2,c3);
676         r[12]=c1;
677         c1=0;
678         mul_add_c(a[6],b[7],c2,c3,c1);
679         mul_add_c(a[7],b[6],c2,c3,c1);
680         r[13]=c2;
681         c2=0;
682         mul_add_c(a[7],b[7],c3,c1,c2);
683         r[14]=c3;
684         r[15]=c1;
685         }
686
687 void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
688         {
689         BN_ULONG c1,c2,c3;
690
691         c1=0;
692         c2=0;
693         c3=0;
694         mul_add_c(a[0],b[0],c1,c2,c3);
695         r[0]=c1;
696         c1=0;
697         mul_add_c(a[0],b[1],c2,c3,c1);
698         mul_add_c(a[1],b[0],c2,c3,c1);
699         r[1]=c2;
700         c2=0;
701         mul_add_c(a[2],b[0],c3,c1,c2);
702         mul_add_c(a[1],b[1],c3,c1,c2);
703         mul_add_c(a[0],b[2],c3,c1,c2);
704         r[2]=c3;
705         c3=0;
706         mul_add_c(a[0],b[3],c1,c2,c3);
707         mul_add_c(a[1],b[2],c1,c2,c3);
708         mul_add_c(a[2],b[1],c1,c2,c3);
709         mul_add_c(a[3],b[0],c1,c2,c3);
710         r[3]=c1;
711         c1=0;
712         mul_add_c(a[3],b[1],c2,c3,c1);
713         mul_add_c(a[2],b[2],c2,c3,c1);
714         mul_add_c(a[1],b[3],c2,c3,c1);
715         r[4]=c2;
716         c2=0;
717         mul_add_c(a[2],b[3],c3,c1,c2);
718         mul_add_c(a[3],b[2],c3,c1,c2);
719         r[5]=c3;
720         c3=0;
721         mul_add_c(a[3],b[3],c1,c2,c3);
722         r[6]=c1;
723         r[7]=c2;
724         }
725
726 void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a)
727         {
728         BN_ULONG c1,c2,c3;
729
730         c1=0;
731         c2=0;
732         c3=0;
733         sqr_add_c(a,0,c1,c2,c3);
734         r[0]=c1;
735         c1=0;
736         sqr_add_c2(a,1,0,c2,c3,c1);
737         r[1]=c2;
738         c2=0;
739         sqr_add_c(a,1,c3,c1,c2);
740         sqr_add_c2(a,2,0,c3,c1,c2);
741         r[2]=c3;
742         c3=0;
743         sqr_add_c2(a,3,0,c1,c2,c3);
744         sqr_add_c2(a,2,1,c1,c2,c3);
745         r[3]=c1;
746         c1=0;
747         sqr_add_c(a,2,c2,c3,c1);
748         sqr_add_c2(a,3,1,c2,c3,c1);
749         sqr_add_c2(a,4,0,c2,c3,c1);
750         r[4]=c2;
751         c2=0;
752         sqr_add_c2(a,5,0,c3,c1,c2);
753         sqr_add_c2(a,4,1,c3,c1,c2);
754         sqr_add_c2(a,3,2,c3,c1,c2);
755         r[5]=c3;
756         c3=0;
757         sqr_add_c(a,3,c1,c2,c3);
758         sqr_add_c2(a,4,2,c1,c2,c3);
759         sqr_add_c2(a,5,1,c1,c2,c3);
760         sqr_add_c2(a,6,0,c1,c2,c3);
761         r[6]=c1;
762         c1=0;
763         sqr_add_c2(a,7,0,c2,c3,c1);
764         sqr_add_c2(a,6,1,c2,c3,c1);
765         sqr_add_c2(a,5,2,c2,c3,c1);
766         sqr_add_c2(a,4,3,c2,c3,c1);
767         r[7]=c2;
768         c2=0;
769         sqr_add_c(a,4,c3,c1,c2);
770         sqr_add_c2(a,5,3,c3,c1,c2);
771         sqr_add_c2(a,6,2,c3,c1,c2);
772         sqr_add_c2(a,7,1,c3,c1,c2);
773         r[8]=c3;
774         c3=0;
775         sqr_add_c2(a,7,2,c1,c2,c3);
776         sqr_add_c2(a,6,3,c1,c2,c3);
777         sqr_add_c2(a,5,4,c1,c2,c3);
778         r[9]=c1;
779         c1=0;
780         sqr_add_c(a,5,c2,c3,c1);
781         sqr_add_c2(a,6,4,c2,c3,c1);
782         sqr_add_c2(a,7,3,c2,c3,c1);
783         r[10]=c2;
784         c2=0;
785         sqr_add_c2(a,7,4,c3,c1,c2);
786         sqr_add_c2(a,6,5,c3,c1,c2);
787         r[11]=c3;
788         c3=0;
789         sqr_add_c(a,6,c1,c2,c3);
790         sqr_add_c2(a,7,5,c1,c2,c3);
791         r[12]=c1;
792         c1=0;
793         sqr_add_c2(a,7,6,c2,c3,c1);
794         r[13]=c2;
795         c2=0;
796         sqr_add_c(a,7,c3,c1,c2);
797         r[14]=c3;
798         r[15]=c1;
799         }
800
801 void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
802         {
803         BN_ULONG c1,c2,c3;
804
805         c1=0;
806         c2=0;
807         c3=0;
808         sqr_add_c(a,0,c1,c2,c3);
809         r[0]=c1;
810         c1=0;
811         sqr_add_c2(a,1,0,c2,c3,c1);
812         r[1]=c2;
813         c2=0;
814         sqr_add_c(a,1,c3,c1,c2);
815         sqr_add_c2(a,2,0,c3,c1,c2);
816         r[2]=c3;
817         c3=0;
818         sqr_add_c2(a,3,0,c1,c2,c3);
819         sqr_add_c2(a,2,1,c1,c2,c3);
820         r[3]=c1;
821         c1=0;
822         sqr_add_c(a,2,c2,c3,c1);
823         sqr_add_c2(a,3,1,c2,c3,c1);
824         r[4]=c2;
825         c2=0;
826         sqr_add_c2(a,3,2,c3,c1,c2);
827         r[5]=c3;
828         c3=0;
829         sqr_add_c(a,3,c1,c2,c3);
830         r[6]=c1;
831         r[7]=c2;
832         }
833
834 #ifdef OPENSSL_NO_ASM
835 #ifdef OPENSSL_BN_ASM_MONT
836 #include <alloca.h>
837 /*
838  * This is essentially reference implementation, which may or may not
839  * result in performance improvement. E.g. on IA-32 this routine was
840  * observed to give 40% faster rsa1024 private key operations and 10%
841  * faster rsa4096 ones, while on AMD64 it improves rsa1024 sign only
842  * by 10% and *worsens* rsa4096 sign by 15%. Once again, it's a
843  * reference implementation, one to be used as starting point for
844  * platform-specific assembler. Mentioned numbers apply to compiler
845  * generated code compiled with and without -DOPENSSL_BN_ASM_MONT and
846  * can vary not only from platform to platform, but even for compiler
847  * versions. Assembler vs. assembler improvement coefficients can
848  * [and are known to] differ and are to be documented elsewhere.
849  */
850 int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0p, int num)
851         {
852         BN_ULONG c0,c1,ml,*tp,n0;
853 #ifdef mul64
854         BN_ULONG mh;
855 #endif
856         volatile BN_ULONG *vp;
857         int i=0,j;
858
859 #if 0   /* template for platform-specific implementation */
860         if (ap==bp)     return bn_sqr_mont(rp,ap,np,n0p,num);
861 #endif
862         vp = tp = alloca((num+2)*sizeof(BN_ULONG));
863
864         n0 = *n0p;
865
866         c0 = 0;
867         ml = bp[0];
868 #ifdef mul64
869         mh = HBITS(ml);
870         ml = LBITS(ml);
871         for (j=0;j<num;++j)
872                 mul(tp[j],ap[j],ml,mh,c0);
873 #else
874         for (j=0;j<num;++j)
875                 mul(tp[j],ap[j],ml,c0);
876 #endif
877
878         tp[num]   = c0;
879         tp[num+1] = 0;
880         goto enter;
881
882         for(i=0;i<num;i++)
883                 {
884                 c0 = 0;
885                 ml = bp[i];
886 #ifdef mul64
887                 mh = HBITS(ml);
888                 ml = LBITS(ml);
889                 for (j=0;j<num;++j)
890                         mul_add(tp[j],ap[j],ml,mh,c0);
891 #else
892                 for (j=0;j<num;++j)
893                         mul_add(tp[j],ap[j],ml,c0);
894 #endif
895                 c1 = (tp[num] + c0)&BN_MASK2;
896                 tp[num]   = c1;
897                 tp[num+1] = (c1<c0?1:0);
898         enter:
899                 c1  = tp[0];
900                 ml = (c1*n0)&BN_MASK2;
901                 c0 = 0;
902 #ifdef mul64
903                 mh = HBITS(ml);
904                 ml = LBITS(ml);
905                 mul_add(c1,np[0],ml,mh,c0);
906 #else
907                 mul_add(c1,ml,np[0],c0);
908 #endif
909                 for(j=1;j<num;j++)
910                         {
911                         c1 = tp[j];
912 #ifdef mul64
913                         mul_add(c1,np[j],ml,mh,c0);
914 #else
915                         mul_add(c1,ml,np[j],c0);
916 #endif
917                         tp[j-1] = c1&BN_MASK2;
918                         }
919                 c1        = (tp[num] + c0)&BN_MASK2;
920                 tp[num-1] = c1;
921                 tp[num]   = tp[num+1] + (c1<c0?1:0);
922                 }
923
924         if (tp[num]!=0 || tp[num-1]>=np[num-1])
925                 {
926                 c0 = bn_sub_words(rp,tp,np,num);
927                 if (tp[num]!=0 || c0==0)
928                         {
929                         for(i=0;i<num+2;i++)    vp[i] = 0;
930                         return 1;
931                         }
932                 }
933         for(i=0;i<num;i++)      rp[i] = tp[i],  vp[i] = 0;
934         vp[num]   = 0;
935         vp[num+1] = 0;
936         return 1;
937         }
938 #else
939 /*
940  * Return value of 0 indicates that multiplication/convolution was not
941  * performed to signal the caller to fall down to alternative/original
942  * code-path.
943  */
944 int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0, int num)
945 {       return 0;       }
946 #endif /* OPENSSL_BN_ASM_MONT */
947 #endif
948
949 #else /* !BN_MUL_COMBA */
950
951 /* hmm... is it faster just to do a multiply? */
952 #undef bn_sqr_comba4
953 #undef bn_sqr_comba8
954 void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
955         {
956         BN_ULONG t[8];
957         bn_sqr_normal(r,a,4,t);
958         }
959
960 void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a)
961         {
962         BN_ULONG t[16];
963         bn_sqr_normal(r,a,8,t);
964         }
965
966 void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
967         {
968         r[4]=bn_mul_words(    &(r[0]),a,4,b[0]);
969         r[5]=bn_mul_add_words(&(r[1]),a,4,b[1]);
970         r[6]=bn_mul_add_words(&(r[2]),a,4,b[2]);
971         r[7]=bn_mul_add_words(&(r[3]),a,4,b[3]);
972         }
973
974 void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b)
975         {
976         r[ 8]=bn_mul_words(    &(r[0]),a,8,b[0]);
977         r[ 9]=bn_mul_add_words(&(r[1]),a,8,b[1]);
978         r[10]=bn_mul_add_words(&(r[2]),a,8,b[2]);
979         r[11]=bn_mul_add_words(&(r[3]),a,8,b[3]);
980         r[12]=bn_mul_add_words(&(r[4]),a,8,b[4]);
981         r[13]=bn_mul_add_words(&(r[5]),a,8,b[5]);
982         r[14]=bn_mul_add_words(&(r[6]),a,8,b[6]);
983         r[15]=bn_mul_add_words(&(r[7]),a,8,b[7]);
984         }
985
986 #ifdef OPENSSL_NO_ASM
987 #ifdef OPENSSL_BN_ASM_MONT
988 #include <alloca.h>
989 int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0p, int num)
990         {
991         BN_ULONG c0,c1,*tp,n0=*n0p;
992         volatile BN_ULONG *vp;
993         int i=0,j;
994
995         vp = tp = alloca((num+2)*sizeof(BN_ULONG));
996
997         for(i=0;i<=num;i++)     tp[i]=0;
998
999         for(i=0;i<num;i++)
1000                 {
1001                 c0         = bn_mul_add_words(tp,ap,num,bp[i]);
1002                 c1         = (tp[num] + c0)&BN_MASK2;
1003                 tp[num]    = c1;
1004                 tp[num+1]  = (c1<c0?1:0);
1005
1006                 c0         = bn_mul_add_words(tp,np,num,tp[0]*n0);
1007                 c1         = (tp[num] + c0)&BN_MASK2;
1008                 tp[num]    = c1;
1009                 tp[num+1] += (c1<c0?1:0);
1010                 for(j=0;j<=num;j++)     tp[j]=tp[j+1];
1011                 }
1012
1013         if (tp[num]!=0 || tp[num-1]>=np[num-1])
1014                 {
1015                 c0 = bn_sub_words(rp,tp,np,num);
1016                 if (tp[num]!=0 || c0==0)
1017                         {
1018                         for(i=0;i<num+2;i++)    vp[i] = 0;
1019                         return 1;
1020                         }
1021                 }
1022         for(i=0;i<num;i++)      rp[i] = tp[i],  vp[i] = 0;
1023         vp[num]   = 0;
1024         vp[num+1] = 0;
1025         return 1;
1026         }
1027 #else
1028 int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, const BN_ULONG *np,const BN_ULONG *n0, int num)
1029 {       return 0;       }
1030 #endif /* OPENSSL_BN_ASM_MONT */
1031 #endif
1032
1033 #endif /* !BN_MUL_COMBA */