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Diffstat (limited to 'src/lib/libcrypto/bn/bn_mul.c')
-rw-r--r--src/lib/libcrypto/bn/bn_mul.c753
1 files changed, 650 insertions, 103 deletions
diff --git a/src/lib/libcrypto/bn/bn_mul.c b/src/lib/libcrypto/bn/bn_mul.c
index d0c04e1d4b..38c47f3d1f 100644
--- a/src/lib/libcrypto/bn/bn_mul.c
+++ b/src/lib/libcrypto/bn/bn_mul.c
@@ -60,150 +60,697 @@
60#include "cryptlib.h" 60#include "cryptlib.h"
61#include "bn_lcl.h" 61#include "bn_lcl.h"
62 62
63/* r must be different to a and b */ 63#ifdef BN_RECURSION
64/* int BN_mmul(r, a, b) */ 64/* r is 2*n2 words in size,
65int BN_mul(r, a, b) 65 * a and b are both n2 words in size.
66BIGNUM *r; 66 * n2 must be a power of 2.
67BIGNUM *a; 67 * We multiply and return the result.
68BIGNUM *b; 68 * t must be 2*n2 words in size
69 * We calulate
70 * a[0]*b[0]
71 * a[0]*b[0]+a[1]*b[1]+(a[0]-a[1])*(b[1]-b[0])
72 * a[1]*b[1]
73 */
74void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
75 BN_ULONG *t)
69 { 76 {
70 int i; 77 int n=n2/2,c1,c2;
71 int max,al,bl; 78 unsigned int neg,zero;
72 BN_ULONG *ap,*bp,*rp; 79 BN_ULONG ln,lo,*p;
73 80
74 al=a->top; 81#ifdef BN_COUNT
75 bl=b->top; 82printf(" bn_mul_recursive %d * %d\n",n2,n2);
76 if ((al == 0) || (bl == 0)) 83#endif
84#ifdef BN_MUL_COMBA
85/* if (n2 == 4)
77 { 86 {
78 r->top=0; 87 bn_mul_comba4(r,a,b);
79 return(1); 88 return;
89 }
90 else */ if (n2 == 8)
91 {
92 bn_mul_comba8(r,a,b);
93 return;
94 }
95#endif
96 if (n2 < BN_MUL_RECURSIVE_SIZE_NORMAL)
97 {
98 /* This should not happen */
99 bn_mul_normal(r,a,n2,b,n2);
100 return;
101 }
102 /* r=(a[0]-a[1])*(b[1]-b[0]) */
103 c1=bn_cmp_words(a,&(a[n]),n);
104 c2=bn_cmp_words(&(b[n]),b,n);
105 zero=neg=0;
106 switch (c1*3+c2)
107 {
108 case -4:
109 bn_sub_words(t, &(a[n]),a, n); /* - */
110 bn_sub_words(&(t[n]),b, &(b[n]),n); /* - */
111 break;
112 case -3:
113 zero=1;
114 break;
115 case -2:
116 bn_sub_words(t, &(a[n]),a, n); /* - */
117 bn_sub_words(&(t[n]),&(b[n]),b, n); /* + */
118 neg=1;
119 break;
120 case -1:
121 case 0:
122 case 1:
123 zero=1;
124 break;
125 case 2:
126 bn_sub_words(t, a, &(a[n]),n); /* + */
127 bn_sub_words(&(t[n]),b, &(b[n]),n); /* - */
128 neg=1;
129 break;
130 case 3:
131 zero=1;
132 break;
133 case 4:
134 bn_sub_words(t, a, &(a[n]),n);
135 bn_sub_words(&(t[n]),&(b[n]),b, n);
136 break;
80 } 137 }
81 138
82 max=(al+bl); 139#ifdef BN_MUL_COMBA
83 if (bn_wexpand(r,max) == NULL) return(0); 140 if (n == 4)
84 r->top=max; 141 {
85 r->neg=a->neg^b->neg; 142 if (!zero)
86 ap=a->d; 143 bn_mul_comba4(&(t[n2]),t,&(t[n]));
87 bp=b->d; 144 else
88 rp=r->d; 145 memset(&(t[n2]),0,8*sizeof(BN_ULONG));
146
147 bn_mul_comba4(r,a,b);
148 bn_mul_comba4(&(r[n2]),&(a[n]),&(b[n]));
149 }
150 else if (n == 8)
151 {
152 if (!zero)
153 bn_mul_comba8(&(t[n2]),t,&(t[n]));
154 else
155 memset(&(t[n2]),0,16*sizeof(BN_ULONG));
156
157 bn_mul_comba8(r,a,b);
158 bn_mul_comba8(&(r[n2]),&(a[n]),&(b[n]));
159 }
160 else
161#endif
162 {
163 p= &(t[n2*2]);
164 if (!zero)
165 bn_mul_recursive(&(t[n2]),t,&(t[n]),n,p);
166 else
167 memset(&(t[n2]),0,n2*sizeof(BN_ULONG));
168 bn_mul_recursive(r,a,b,n,p);
169 bn_mul_recursive(&(r[n2]),&(a[n]),&(b[n]),n,p);
170 }
89 171
90 rp[al]=bn_mul_words(rp,ap,al,*(bp++)); 172 /* t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
91 rp++; 173 * r[10] holds (a[0]*b[0])
92 for (i=1; i<bl; i++) 174 * r[32] holds (b[1]*b[1])
175 */
176
177 c1=(int)(bn_add_words(t,r,&(r[n2]),n2));
178
179 if (neg) /* if t[32] is negative */
93 { 180 {
94 rp[al]=bn_mul_add_words(rp,ap,al,*(bp++)); 181 c1-=(int)(bn_sub_words(&(t[n2]),t,&(t[n2]),n2));
95 rp++; 182 }
183 else
184 {
185 /* Might have a carry */
186 c1+=(int)(bn_add_words(&(t[n2]),&(t[n2]),t,n2));
96 } 187 }
97 if (r->d[max-1] == 0) r->top--;
98 return(1);
99 }
100 188
101#if 0 189 /* t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
102#include "stack.h" 190 * r[10] holds (a[0]*b[0])
191 * r[32] holds (b[1]*b[1])
192 * c1 holds the carry bits
193 */
194 c1+=(int)(bn_add_words(&(r[n]),&(r[n]),&(t[n2]),n2));
195 if (c1)
196 {
197 p= &(r[n+n2]);
198 lo= *p;
199 ln=(lo+c1)&BN_MASK2;
200 *p=ln;
103 201
104int limit=16; 202 /* The overflow will stop before we over write
203 * words we should not overwrite */
204 if (ln < (BN_ULONG)c1)
205 {
206 do {
207 p++;
208 lo= *p;
209 ln=(lo+1)&BN_MASK2;
210 *p=ln;
211 } while (ln == 0);
212 }
213 }
214 }
105 215
106typedef struct bn_pool_st 216/* n+tn is the word length
217 * t needs to be n*4 is size, as does r */
218void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int tn,
219 int n, BN_ULONG *t)
107 { 220 {
108 int used; 221 int i,j,n2=n*2;
109 int tos; 222 unsigned int c1;
110 STACK *sk; 223 BN_ULONG ln,lo,*p;
111 } BN_POOL;
112 224
113BIGNUM *BN_POOL_push(bp) 225#ifdef BN_COUNT
114BN_POOL *bp; 226printf(" bn_mul_part_recursive %d * %d\n",tn+n,tn+n);
115 { 227#endif
116 BIGNUM *ret; 228 if (n < 8)
229 {
230 i=tn+n;
231 bn_mul_normal(r,a,i,b,i);
232 return;
233 }
234
235 /* r=(a[0]-a[1])*(b[1]-b[0]) */
236 bn_sub_words(t, a, &(a[n]),n); /* + */
237 bn_sub_words(&(t[n]),b, &(b[n]),n); /* - */
117 238
118 if (bp->used >= bp->tos) 239/* if (n == 4)
240 {
241 bn_mul_comba4(&(t[n2]),t,&(t[n]));
242 bn_mul_comba4(r,a,b);
243 bn_mul_normal(&(r[n2]),&(a[n]),tn,&(b[n]),tn);
244 memset(&(r[n2+tn*2]),0,sizeof(BN_ULONG)*(n2-tn*2));
245 }
246 else */ if (n == 8)
119 { 247 {
120 ret=BN_new(); 248 bn_mul_comba8(&(t[n2]),t,&(t[n]));
121 sk_push(bp->sk,(char *)ret); 249 bn_mul_comba8(r,a,b);
122 bp->tos++; 250 bn_mul_normal(&(r[n2]),&(a[n]),tn,&(b[n]),tn);
123 bp->used++; 251 memset(&(r[n2+tn*2]),0,sizeof(BN_ULONG)*(n2-tn*2));
124 } 252 }
125 else 253 else
126 { 254 {
127 ret=(BIGNUM *)sk_value(bp->sk,bp->used); 255 p= &(t[n2*2]);
128 bp->used++; 256 bn_mul_recursive(&(t[n2]),t,&(t[n]),n,p);
257 bn_mul_recursive(r,a,b,n,p);
258 i=n/2;
259 /* If there is only a bottom half to the number,
260 * just do it */
261 j=tn-i;
262 if (j == 0)
263 {
264 bn_mul_recursive(&(r[n2]),&(a[n]),&(b[n]),i,p);
265 memset(&(r[n2+i*2]),0,sizeof(BN_ULONG)*(n2-i*2));
266 }
267 else if (j > 0) /* eg, n == 16, i == 8 and tn == 11 */
268 {
269 bn_mul_part_recursive(&(r[n2]),&(a[n]),&(b[n]),
270 j,i,p);
271 memset(&(r[n2+tn*2]),0,
272 sizeof(BN_ULONG)*(n2-tn*2));
273 }
274 else /* (j < 0) eg, n == 16, i == 8 and tn == 5 */
275 {
276 memset(&(r[n2]),0,sizeof(BN_ULONG)*n2);
277 if (tn < BN_MUL_RECURSIVE_SIZE_NORMAL)
278 {
279 bn_mul_normal(&(r[n2]),&(a[n]),tn,&(b[n]),tn);
280 }
281 else
282 {
283 for (;;)
284 {
285 i/=2;
286 if (i < tn)
287 {
288 bn_mul_part_recursive(&(r[n2]),
289 &(a[n]),&(b[n]),
290 tn-i,i,p);
291 break;
292 }
293 else if (i == tn)
294 {
295 bn_mul_recursive(&(r[n2]),
296 &(a[n]),&(b[n]),
297 i,p);
298 break;
299 }
300 }
301 }
302 }
303 }
304
305 /* t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
306 * r[10] holds (a[0]*b[0])
307 * r[32] holds (b[1]*b[1])
308 */
309
310 c1=(int)(bn_add_words(t,r,&(r[n2]),n2));
311 c1-=(int)(bn_sub_words(&(t[n2]),t,&(t[n2]),n2));
312
313 /* t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
314 * r[10] holds (a[0]*b[0])
315 * r[32] holds (b[1]*b[1])
316 * c1 holds the carry bits
317 */
318 c1+=(int)(bn_add_words(&(r[n]),&(r[n]),&(t[n2]),n2));
319 if (c1)
320 {
321 p= &(r[n+n2]);
322 lo= *p;
323 ln=(lo+c1)&BN_MASK2;
324 *p=ln;
325
326 /* The overflow will stop before we over write
327 * words we should not overwrite */
328 if (ln < c1)
329 {
330 do {
331 p++;
332 lo= *p;
333 ln=(lo+1)&BN_MASK2;
334 *p=ln;
335 } while (ln == 0);
336 }
129 } 337 }
130 return(ret);
131 } 338 }
132 339
133void BN_POOL_pop(bp,num) 340/* a and b must be the same size, which is n2.
134BN_POOL *bp; 341 * r needs to be n2 words and t needs to be n2*2
135int num; 342 */
343void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
344 BN_ULONG *t)
136 { 345 {
137 bp->used-=num; 346 int n=n2/2;
347
348#ifdef BN_COUNT
349printf(" bn_mul_low_recursive %d * %d\n",n2,n2);
350#endif
351
352 bn_mul_recursive(r,a,b,n,&(t[0]));
353 if (n >= BN_MUL_LOW_RECURSIVE_SIZE_NORMAL)
354 {
355 bn_mul_low_recursive(&(t[0]),&(a[0]),&(b[n]),n,&(t[n2]));
356 bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
357 bn_mul_low_recursive(&(t[0]),&(a[n]),&(b[0]),n,&(t[n2]));
358 bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
359 }
360 else
361 {
362 bn_mul_low_normal(&(t[0]),&(a[0]),&(b[n]),n);
363 bn_mul_low_normal(&(t[n]),&(a[n]),&(b[0]),n);
364 bn_add_words(&(r[n]),&(r[n]),&(t[0]),n);
365 bn_add_words(&(r[n]),&(r[n]),&(t[n]),n);
366 }
138 } 367 }
139 368
140int BN_mul(r,a,b) 369/* a and b must be the same size, which is n2.
141BIGNUM *r,*a,*b; 370 * r needs to be n2 words and t needs to be n2*2
371 * l is the low words of the output.
372 * t needs to be n2*3
373 */
374void bn_mul_high(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, BN_ULONG *l, int n2,
375 BN_ULONG *t)
142 { 376 {
143 static BN_POOL bp; 377 int i,n;
144 static init=1; 378 int c1,c2;
379 int neg,oneg,zero;
380 BN_ULONG ll,lc,*lp,*mp;
381
382#ifdef BN_COUNT
383printf(" bn_mul_high %d * %d\n",n2,n2);
384#endif
385 n=n2/2;
386
387 /* Calculate (al-ah)*(bh-bl) */
388 neg=zero=0;
389 c1=bn_cmp_words(&(a[0]),&(a[n]),n);
390 c2=bn_cmp_words(&(b[n]),&(b[0]),n);
391 switch (c1*3+c2)
392 {
393 case -4:
394 bn_sub_words(&(r[0]),&(a[n]),&(a[0]),n);
395 bn_sub_words(&(r[n]),&(b[0]),&(b[n]),n);
396 break;
397 case -3:
398 zero=1;
399 break;
400 case -2:
401 bn_sub_words(&(r[0]),&(a[n]),&(a[0]),n);
402 bn_sub_words(&(r[n]),&(b[n]),&(b[0]),n);
403 neg=1;
404 break;
405 case -1:
406 case 0:
407 case 1:
408 zero=1;
409 break;
410 case 2:
411 bn_sub_words(&(r[0]),&(a[0]),&(a[n]),n);
412 bn_sub_words(&(r[n]),&(b[0]),&(b[n]),n);
413 neg=1;
414 break;
415 case 3:
416 zero=1;
417 break;
418 case 4:
419 bn_sub_words(&(r[0]),&(a[0]),&(a[n]),n);
420 bn_sub_words(&(r[n]),&(b[n]),&(b[0]),n);
421 break;
422 }
423
424 oneg=neg;
425 /* t[10] = (a[0]-a[1])*(b[1]-b[0]) */
426 /* r[10] = (a[1]*b[1]) */
427#ifdef BN_MUL_COMBA
428 if (n == 8)
429 {
430 bn_mul_comba8(&(t[0]),&(r[0]),&(r[n]));
431 bn_mul_comba8(r,&(a[n]),&(b[n]));
432 }
433 else
434#endif
435 {
436 bn_mul_recursive(&(t[0]),&(r[0]),&(r[n]),n,&(t[n2]));
437 bn_mul_recursive(r,&(a[n]),&(b[n]),n,&(t[n2]));
438 }
439
440 /* s0 == low(al*bl)
441 * s1 == low(ah*bh)+low((al-ah)*(bh-bl))+low(al*bl)+high(al*bl)
442 * We know s0 and s1 so the only unknown is high(al*bl)
443 * high(al*bl) == s1 - low(ah*bh+s0+(al-ah)*(bh-bl))
444 * high(al*bl) == s1 - (r[0]+l[0]+t[0])
445 */
446 if (l != NULL)
447 {
448 lp= &(t[n2+n]);
449 c1=(int)(bn_add_words(lp,&(r[0]),&(l[0]),n));
450 }
451 else
452 {
453 c1=0;
454 lp= &(r[0]);
455 }
456
457 if (neg)
458 neg=(int)(bn_sub_words(&(t[n2]),lp,&(t[0]),n));
459 else
460 {
461 bn_add_words(&(t[n2]),lp,&(t[0]),n);
462 neg=0;
463 }
464
465 if (l != NULL)
466 {
467 bn_sub_words(&(t[n2+n]),&(l[n]),&(t[n2]),n);
468 }
469 else
470 {
471 lp= &(t[n2+n]);
472 mp= &(t[n2]);
473 for (i=0; i<n; i++)
474 lp[i]=((~mp[i])+1)&BN_MASK2;
475 }
476
477 /* s[0] = low(al*bl)
478 * t[3] = high(al*bl)
479 * t[10] = (a[0]-a[1])*(b[1]-b[0]) neg is the sign
480 * r[10] = (a[1]*b[1])
481 */
482 /* R[10] = al*bl
483 * R[21] = al*bl + ah*bh + (a[0]-a[1])*(b[1]-b[0])
484 * R[32] = ah*bh
485 */
486 /* R[1]=t[3]+l[0]+r[0](+-)t[0] (have carry/borrow)
487 * R[2]=r[0]+t[3]+r[1](+-)t[1] (have carry/borrow)
488 * R[3]=r[1]+(carry/borrow)
489 */
490 if (l != NULL)
491 {
492 lp= &(t[n2]);
493 c1= (int)(bn_add_words(lp,&(t[n2+n]),&(l[0]),n));
494 }
495 else
496 {
497 lp= &(t[n2+n]);
498 c1=0;
499 }
500 c1+=(int)(bn_add_words(&(t[n2]),lp, &(r[0]),n));
501 if (oneg)
502 c1-=(int)(bn_sub_words(&(t[n2]),&(t[n2]),&(t[0]),n));
503 else
504 c1+=(int)(bn_add_words(&(t[n2]),&(t[n2]),&(t[0]),n));
145 505
146 if (init) 506 c2 =(int)(bn_add_words(&(r[0]),&(r[0]),&(t[n2+n]),n));
507 c2+=(int)(bn_add_words(&(r[0]),&(r[0]),&(r[n]),n));
508 if (oneg)
509 c2-=(int)(bn_sub_words(&(r[0]),&(r[0]),&(t[n]),n));
510 else
511 c2+=(int)(bn_add_words(&(r[0]),&(r[0]),&(t[n]),n));
512
513 if (c1 != 0) /* Add starting at r[0], could be +ve or -ve */
147 { 514 {
148 bp.used=0; 515 i=0;
149 bp.tos=0; 516 if (c1 > 0)
150 bp.sk=sk_new_null(); 517 {
151 init=0; 518 lc=c1;
519 do {
520 ll=(r[i]+lc)&BN_MASK2;
521 r[i++]=ll;
522 lc=(lc > ll);
523 } while (lc);
524 }
525 else
526 {
527 lc= -c1;
528 do {
529 ll=r[i];
530 r[i++]=(ll-lc)&BN_MASK2;
531 lc=(lc > ll);
532 } while (lc);
533 }
534 }
535 if (c2 != 0) /* Add starting at r[1] */
536 {
537 i=n;
538 if (c2 > 0)
539 {
540 lc=c2;
541 do {
542 ll=(r[i]+lc)&BN_MASK2;
543 r[i++]=ll;
544 lc=(lc > ll);
545 } while (lc);
546 }
547 else
548 {
549 lc= -c2;
550 do {
551 ll=r[i];
552 r[i++]=(ll-lc)&BN_MASK2;
553 lc=(lc > ll);
554 } while (lc);
555 }
152 } 556 }
153 return(BN_mm(r,a,b,&bp));
154 } 557 }
558#endif
155 559
156/* r must be different to a and b */ 560int BN_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b, BN_CTX *ctx)
157int BN_mm(m, A, B, bp)
158BIGNUM *m,*A,*B;
159BN_POOL *bp;
160 { 561 {
161 int i,num; 562 int top,al,bl;
162 int an,bn; 563 BIGNUM *rr;
163 BIGNUM *a,*b,*c,*d,*ac,*bd; 564#ifdef BN_RECURSION
565 BIGNUM *t;
566 int i,j,k;
567#endif
568
569#ifdef BN_COUNT
570printf("BN_mul %d * %d\n",a->top,b->top);
571#endif
572
573 bn_check_top(a);
574 bn_check_top(b);
575 bn_check_top(r);
576
577 al=a->top;
578 bl=b->top;
579 r->neg=a->neg^b->neg;
580
581 if ((al == 0) || (bl == 0))
582 {
583 BN_zero(r);
584 return(1);
585 }
586 top=al+bl;
164 587
165 an=A->top; 588 if ((r == a) || (r == b))
166 bn=B->top; 589 rr= &(ctx->bn[ctx->tos+1]);
167 if ((an <= limit) || (bn <= limit)) 590 else
591 rr=r;
592
593#if defined(BN_MUL_COMBA) || defined(BN_RECURSION)
594 if (al == bl)
168 { 595 {
169 return(BN_mmul(m,A,B)); 596# ifdef BN_MUL_COMBA
597/* if (al == 4)
598 {
599 if (bn_wexpand(rr,8) == NULL) return(0);
600 rr->top=8;
601 bn_mul_comba4(rr->d,a->d,b->d);
602 goto end;
603 }
604 else */ if (al == 8)
605 {
606 if (bn_wexpand(rr,16) == NULL) return(0);
607 rr->top=16;
608 bn_mul_comba8(rr->d,a->d,b->d);
609 goto end;
610 }
611 else
612# endif
613#ifdef BN_RECURSION
614 if (al < BN_MULL_SIZE_NORMAL)
615#endif
616 {
617 if (bn_wexpand(rr,top) == NULL) return(0);
618 rr->top=top;
619 bn_mul_normal(rr->d,a->d,al,b->d,bl);
620 goto end;
621 }
622# ifdef BN_RECURSION
623 goto symetric;
624# endif
170 } 625 }
626#endif
627#ifdef BN_RECURSION
628 else if ((al < BN_MULL_SIZE_NORMAL) || (bl < BN_MULL_SIZE_NORMAL))
629 {
630 if (bn_wexpand(rr,top) == NULL) return(0);
631 rr->top=top;
632 bn_mul_normal(rr->d,a->d,al,b->d,bl);
633 goto end;
634 }
635 else
636 {
637 i=(al-bl);
638 if ((i == 1) && !BN_get_flags(b,BN_FLG_STATIC_DATA))
639 {
640 bn_wexpand(b,al);
641 b->d[bl]=0;
642 bl++;
643 goto symetric;
644 }
645 else if ((i == -1) && !BN_get_flags(a,BN_FLG_STATIC_DATA))
646 {
647 bn_wexpand(a,bl);
648 a->d[al]=0;
649 al++;
650 goto symetric;
651 }
652 }
653#endif
171 654
172 a=BN_POOL_push(bp); 655 /* asymetric and >= 4 */
173 b=BN_POOL_push(bp); 656 if (bn_wexpand(rr,top) == NULL) return(0);
174 c=BN_POOL_push(bp); 657 rr->top=top;
175 d=BN_POOL_push(bp); 658 bn_mul_normal(rr->d,a->d,al,b->d,bl);
176 ac=BN_POOL_push(bp);
177 bd=BN_POOL_push(bp);
178 659
179 num=(an <= bn)?an:bn; 660#ifdef BN_RECURSION
180 num=1<<(BN_num_bits_word(num-1)-1); 661 if (0)
662 {
663symetric:
664 /* symetric and > 4 */
665 /* 16 or larger */
666 j=BN_num_bits_word((BN_ULONG)al);
667 j=1<<(j-1);
668 k=j+j;
669 t= &(ctx->bn[ctx->tos]);
670 if (al == j) /* exact multiple */
671 {
672 bn_wexpand(t,k*2);
673 bn_wexpand(rr,k*2);
674 bn_mul_recursive(rr->d,a->d,b->d,al,t->d);
675 }
676 else
677 {
678 bn_wexpand(a,k);
679 bn_wexpand(b,k);
680 bn_wexpand(t,k*4);
681 bn_wexpand(rr,k*4);
682 for (i=a->top; i<k; i++)
683 a->d[i]=0;
684 for (i=b->top; i<k; i++)
685 b->d[i]=0;
686 bn_mul_part_recursive(rr->d,a->d,b->d,al-j,j,t->d);
687 }
688 rr->top=top;
689 }
690#endif
691#if defined(BN_MUL_COMBA) || defined(BN_RECURSION)
692end:
693#endif
694 bn_fix_top(rr);
695 if (r != rr) BN_copy(r,rr);
696 return(1);
697 }
181 698
182 /* Are going to now chop things into 'num' word chunks. */ 699void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, int nb)
183 num*=BN_BITS2; 700 {
701 BN_ULONG *rr;
184 702
185 BN_copy(a,A); 703#ifdef BN_COUNT
186 BN_mask_bits(a,num); 704printf(" bn_mul_normal %d * %d\n",na,nb);
187 BN_rshift(b,A,num); 705#endif
188 706
189 BN_copy(c,B); 707 if (na < nb)
190 BN_mask_bits(c,num); 708 {
191 BN_rshift(d,B,num); 709 int itmp;
710 BN_ULONG *ltmp;
192 711
193 BN_sub(ac ,b,a); 712 itmp=na; na=nb; nb=itmp;
194 BN_sub(bd,c,d); 713 ltmp=a; a=b; b=ltmp;
195 BN_mm(m,ac,bd,bp);
196 BN_mm(ac,a,c,bp);
197 BN_mm(bd,b,d,bp);
198 714
199 BN_add(m,m,ac); 715 }
200 BN_add(m,m,bd); 716 rr= &(r[na]);
201 BN_lshift(m,m,num); 717 rr[0]=bn_mul_words(r,a,na,b[0]);
202 BN_lshift(bd,bd,num*2);
203 718
204 BN_add(m,m,ac); 719 for (;;)
205 BN_add(m,m,bd); 720 {
206 BN_POOL_pop(bp,6); 721 if (--nb <= 0) return;
207 return(1); 722 rr[1]=bn_mul_add_words(&(r[1]),a,na,b[1]);
723 if (--nb <= 0) return;
724 rr[2]=bn_mul_add_words(&(r[2]),a,na,b[2]);
725 if (--nb <= 0) return;
726 rr[3]=bn_mul_add_words(&(r[3]),a,na,b[3]);
727 if (--nb <= 0) return;
728 rr[4]=bn_mul_add_words(&(r[4]),a,na,b[4]);
729 rr+=4;
730 r+=4;
731 b+=4;
732 }
208 } 733 }
734
735void bn_mul_low_normal(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n)
736 {
737#ifdef BN_COUNT
738printf(" bn_mul_low_normal %d * %d\n",n,n);
209#endif 739#endif
740 bn_mul_words(r,a,n,b[0]);
741
742 for (;;)
743 {
744 if (--n <= 0) return;
745 bn_mul_add_words(&(r[1]),a,n,b[1]);
746 if (--n <= 0) return;
747 bn_mul_add_words(&(r[2]),a,n,b[2]);
748 if (--n <= 0) return;
749 bn_mul_add_words(&(r[3]),a,n,b[3]);
750 if (--n <= 0) return;
751 bn_mul_add_words(&(r[4]),a,n,b[4]);
752 r+=4;
753 b+=4;
754 }
755 }
756