1 /* $OpenBSD: bn_lcl.h,v 1.30 2018/11/05 23:52:47 tb Exp $ */ 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 * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. 60 * 61 * Redistribution and use in source and binary forms, with or without 62 * modification, are permitted provided that the following conditions 63 * are met: 64 * 65 * 1. Redistributions of source code must retain the above copyright 66 * notice, this list of conditions and the following disclaimer. 67 * 68 * 2. Redistributions in binary form must reproduce the above copyright 69 * notice, this list of conditions and the following disclaimer in 70 * the documentation and/or other materials provided with the 71 * distribution. 72 * 73 * 3. All advertising materials mentioning features or use of this 74 * software must display the following acknowledgment: 75 * "This product includes software developed by the OpenSSL Project 76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 77 * 78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 79 * endorse or promote products derived from this software without 80 * prior written permission. For written permission, please contact 81 * openssl-core@openssl.org. 82 * 83 * 5. Products derived from this software may not be called "OpenSSL" 84 * nor may "OpenSSL" appear in their names without prior written 85 * permission of the OpenSSL Project. 86 * 87 * 6. Redistributions of any form whatsoever must retain the following 88 * acknowledgment: 89 * "This product includes software developed by the OpenSSL Project 90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 91 * 92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 103 * OF THE POSSIBILITY OF SUCH DAMAGE. 104 * ==================================================================== 105 * 106 * This product includes cryptographic software written by Eric Young 107 * (eay@cryptsoft.com). This product includes software written by Tim 108 * Hudson (tjh@cryptsoft.com). 109 * 110 */ 111 112 #ifndef HEADER_BN_LCL_H 113 #define HEADER_BN_LCL_H 114 115 #include <openssl/opensslconf.h> 116 117 #include <openssl/bn.h> 118 119 __BEGIN_HIDDEN_DECLS 120 121 /* 122 * BN_window_bits_for_exponent_size -- macro for sliding window mod_exp functions 123 * 124 * 125 * For window size 'w' (w >= 2) and a random 'b' bits exponent, 126 * the number of multiplications is a constant plus on average 127 * 128 * 2^(w-1) + (b-w)/(w+1); 129 * 130 * here 2^(w-1) is for precomputing the table (we actually need 131 * entries only for windows that have the lowest bit set), and 132 * (b-w)/(w+1) is an approximation for the expected number of 133 * w-bit windows, not counting the first one. 134 * 135 * Thus we should use 136 * 137 * w >= 6 if b > 671 138 * w = 5 if 671 > b > 239 139 * w = 4 if 239 > b > 79 140 * w = 3 if 79 > b > 23 141 * w <= 2 if 23 > b 142 * 143 * (with draws in between). Very small exponents are often selected 144 * with low Hamming weight, so we use w = 1 for b <= 23. 145 */ 146 #define BN_window_bits_for_exponent_size(b) \ 147 ((b) > 671 ? 6 : \ 148 (b) > 239 ? 5 : \ 149 (b) > 79 ? 4 : \ 150 (b) > 23 ? 3 : 1) 151 152 153 /* BN_mod_exp_mont_consttime is based on the assumption that the 154 * L1 data cache line width of the target processor is at least 155 * the following value. 156 */ 157 #define MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH ( 64 ) 158 #define MOD_EXP_CTIME_MIN_CACHE_LINE_MASK (MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH - 1) 159 160 /* Window sizes optimized for fixed window size modular exponentiation 161 * algorithm (BN_mod_exp_mont_consttime). 162 * 163 * To achieve the security goals of BN_mode_exp_mont_consttime, the 164 * maximum size of the window must not exceed 165 * log_2(MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH). 166 * 167 * Window size thresholds are defined for cache line sizes of 32 and 64, 168 * cache line sizes where log_2(32)=5 and log_2(64)=6 respectively. A 169 * window size of 7 should only be used on processors that have a 128 170 * byte or greater cache line size. 171 */ 172 #if MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH == 64 173 174 # define BN_window_bits_for_ctime_exponent_size(b) \ 175 ((b) > 937 ? 6 : \ 176 (b) > 306 ? 5 : \ 177 (b) > 89 ? 4 : \ 178 (b) > 22 ? 3 : 1) 179 # define BN_MAX_WINDOW_BITS_FOR_CTIME_EXPONENT_SIZE (6) 180 181 #elif MOD_EXP_CTIME_MIN_CACHE_LINE_WIDTH == 32 182 183 # define BN_window_bits_for_ctime_exponent_size(b) \ 184 ((b) > 306 ? 5 : \ 185 (b) > 89 ? 4 : \ 186 (b) > 22 ? 3 : 1) 187 # define BN_MAX_WINDOW_BITS_FOR_CTIME_EXPONENT_SIZE (5) 188 189 #endif 190 191 192 /* Pentium pro 16,16,16,32,64 */ 193 /* Alpha 16,16,16,16.64 */ 194 #define BN_MULL_SIZE_NORMAL (16) /* 32 */ 195 #define BN_MUL_RECURSIVE_SIZE_NORMAL (16) /* 32 less than */ 196 #define BN_SQR_RECURSIVE_SIZE_NORMAL (16) /* 32 */ 197 #define BN_MUL_LOW_RECURSIVE_SIZE_NORMAL (32) /* 32 */ 198 #define BN_MONT_CTX_SET_SIZE_WORD (64) /* 32 */ 199 200 #if !defined(OPENSSL_NO_ASM) && !defined(OPENSSL_NO_INLINE_ASM) 201 /* 202 * BN_UMULT_HIGH section. 203 * 204 * No, I'm not trying to overwhelm you when stating that the 205 * product of N-bit numbers is 2*N bits wide:-) No, I don't expect 206 * you to be impressed when I say that if the compiler doesn't 207 * support 2*N integer type, then you have to replace every N*N 208 * multiplication with 4 (N/2)*(N/2) accompanied by some shifts 209 * and additions which unavoidably results in severe performance 210 * penalties. Of course provided that the hardware is capable of 211 * producing 2*N result... That's when you normally start 212 * considering assembler implementation. However! It should be 213 * pointed out that some CPUs (most notably Alpha, PowerPC and 214 * upcoming IA-64 family:-) provide *separate* instruction 215 * calculating the upper half of the product placing the result 216 * into a general purpose register. Now *if* the compiler supports 217 * inline assembler, then it's not impossible to implement the 218 * "bignum" routines (and have the compiler optimize 'em) 219 * exhibiting "native" performance in C. That's what BN_UMULT_HIGH 220 * macro is about:-) 221 * 222 * <appro@fy.chalmers.se> 223 */ 224 # if defined(__alpha) 225 # if defined(__GNUC__) && __GNUC__>=2 226 # define BN_UMULT_HIGH(a,b) ({ \ 227 BN_ULONG ret; \ 228 asm ("umulh %1,%2,%0" \ 229 : "=r"(ret) \ 230 : "r"(a), "r"(b)); \ 231 ret; }) 232 # endif /* compiler */ 233 # elif defined(_ARCH_PPC) && defined(_LP64) 234 # if defined(__GNUC__) && __GNUC__>=2 235 # define BN_UMULT_HIGH(a,b) ({ \ 236 BN_ULONG ret; \ 237 asm ("mulhdu %0,%1,%2" \ 238 : "=r"(ret) \ 239 : "r"(a), "r"(b)); \ 240 ret; }) 241 # endif /* compiler */ 242 # elif (defined(__x86_64) || defined(__x86_64__)) && defined(_LP64) 243 # if defined(__GNUC__) && __GNUC__>=2 244 # define BN_UMULT_HIGH(a,b) ({ \ 245 BN_ULONG ret,discard; \ 246 asm ("mulq %3" \ 247 : "=a"(discard),"=d"(ret) \ 248 : "a"(a), "g"(b) \ 249 : "cc"); \ 250 ret; }) 251 # define BN_UMULT_LOHI(low,high,a,b) \ 252 asm ("mulq %3" \ 253 : "=a"(low),"=d"(high) \ 254 : "a"(a),"g"(b) \ 255 : "cc"); 256 # endif 257 # elif defined(__mips) && defined(_LP64) 258 # if defined(__GNUC__) && __GNUC__>=2 259 # if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4) /* "h" constraint is no more since 4.4 */ 260 # define BN_UMULT_HIGH(a,b) (((__uint128_t)(a)*(b))>>64) 261 # define BN_UMULT_LOHI(low,high,a,b) ({ \ 262 __uint128_t ret=(__uint128_t)(a)*(b); \ 263 (high)=ret>>64; (low)=ret; }) 264 # else 265 # define BN_UMULT_HIGH(a,b) ({ \ 266 BN_ULONG ret; \ 267 asm ("dmultu %1,%2" \ 268 : "=h"(ret) \ 269 : "r"(a), "r"(b) : "l"); \ 270 ret; }) 271 # define BN_UMULT_LOHI(low,high,a,b)\ 272 asm ("dmultu %2,%3" \ 273 : "=l"(low),"=h"(high) \ 274 : "r"(a), "r"(b)); 275 # endif 276 # endif 277 # endif /* cpu */ 278 #endif /* OPENSSL_NO_ASM */ 279 280 /************************************************************* 281 * Using the long long type 282 */ 283 #define Lw(t) (((BN_ULONG)(t))&BN_MASK2) 284 #define Hw(t) (((BN_ULONG)((t)>>BN_BITS2))&BN_MASK2) 285 286 #ifdef BN_DEBUG_RAND 287 #define bn_clear_top2max(a) \ 288 { \ 289 int ind = (a)->dmax - (a)->top; \ 290 BN_ULONG *ftl = &(a)->d[(a)->top-1]; \ 291 for (; ind != 0; ind--) \ 292 *(++ftl) = 0x0; \ 293 } 294 #else 295 #define bn_clear_top2max(a) 296 #endif 297 298 #ifdef BN_LLONG 299 #define mul_add(r,a,w,c) { \ 300 BN_ULLONG t; \ 301 t=(BN_ULLONG)w * (a) + (r) + (c); \ 302 (r)= Lw(t); \ 303 (c)= Hw(t); \ 304 } 305 306 #define mul(r,a,w,c) { \ 307 BN_ULLONG t; \ 308 t=(BN_ULLONG)w * (a) + (c); \ 309 (r)= Lw(t); \ 310 (c)= Hw(t); \ 311 } 312 313 #define sqr(r0,r1,a) { \ 314 BN_ULLONG t; \ 315 t=(BN_ULLONG)(a)*(a); \ 316 (r0)=Lw(t); \ 317 (r1)=Hw(t); \ 318 } 319 320 #elif defined(BN_UMULT_LOHI) 321 #define mul_add(r,a,w,c) { \ 322 BN_ULONG high,low,ret,tmp=(a); \ 323 ret = (r); \ 324 BN_UMULT_LOHI(low,high,w,tmp); \ 325 ret += (c); \ 326 (c) = (ret<(c))?1:0; \ 327 (c) += high; \ 328 ret += low; \ 329 (c) += (ret<low)?1:0; \ 330 (r) = ret; \ 331 } 332 333 #define mul(r,a,w,c) { \ 334 BN_ULONG high,low,ret,ta=(a); \ 335 BN_UMULT_LOHI(low,high,w,ta); \ 336 ret = low + (c); \ 337 (c) = high; \ 338 (c) += (ret<low)?1:0; \ 339 (r) = ret; \ 340 } 341 342 #define sqr(r0,r1,a) { \ 343 BN_ULONG tmp=(a); \ 344 BN_UMULT_LOHI(r0,r1,tmp,tmp); \ 345 } 346 347 #elif defined(BN_UMULT_HIGH) 348 #define mul_add(r,a,w,c) { \ 349 BN_ULONG high,low,ret,tmp=(a); \ 350 ret = (r); \ 351 high= BN_UMULT_HIGH(w,tmp); \ 352 ret += (c); \ 353 low = (w) * tmp; \ 354 (c) = (ret<(c))?1:0; \ 355 (c) += high; \ 356 ret += low; \ 357 (c) += (ret<low)?1:0; \ 358 (r) = ret; \ 359 } 360 361 #define mul(r,a,w,c) { \ 362 BN_ULONG high,low,ret,ta=(a); \ 363 low = (w) * ta; \ 364 high= BN_UMULT_HIGH(w,ta); \ 365 ret = low + (c); \ 366 (c) = high; \ 367 (c) += (ret<low)?1:0; \ 368 (r) = ret; \ 369 } 370 371 #define sqr(r0,r1,a) { \ 372 BN_ULONG tmp=(a); \ 373 (r0) = tmp * tmp; \ 374 (r1) = BN_UMULT_HIGH(tmp,tmp); \ 375 } 376 377 #else 378 /************************************************************* 379 * No long long type 380 */ 381 382 #define LBITS(a) ((a)&BN_MASK2l) 383 #define HBITS(a) (((a)>>BN_BITS4)&BN_MASK2l) 384 #define L2HBITS(a) (((a)<<BN_BITS4)&BN_MASK2) 385 386 #define mul64(l,h,bl,bh) \ 387 { \ 388 BN_ULONG m,m1,lt,ht; \ 389 \ 390 lt=l; \ 391 ht=h; \ 392 m =(bh)*(lt); \ 393 lt=(bl)*(lt); \ 394 m1=(bl)*(ht); \ 395 ht =(bh)*(ht); \ 396 m=(m+m1)&BN_MASK2; if (m < m1) ht+=L2HBITS((BN_ULONG)1); \ 397 ht+=HBITS(m); \ 398 m1=L2HBITS(m); \ 399 lt=(lt+m1)&BN_MASK2; if (lt < m1) ht++; \ 400 (l)=lt; \ 401 (h)=ht; \ 402 } 403 404 #define sqr64(lo,ho,in) \ 405 { \ 406 BN_ULONG l,h,m; \ 407 \ 408 h=(in); \ 409 l=LBITS(h); \ 410 h=HBITS(h); \ 411 m =(l)*(h); \ 412 l*=l; \ 413 h*=h; \ 414 h+=(m&BN_MASK2h1)>>(BN_BITS4-1); \ 415 m =(m&BN_MASK2l)<<(BN_BITS4+1); \ 416 l=(l+m)&BN_MASK2; if (l < m) h++; \ 417 (lo)=l; \ 418 (ho)=h; \ 419 } 420 421 #define mul_add(r,a,bl,bh,c) { \ 422 BN_ULONG l,h; \ 423 \ 424 h= (a); \ 425 l=LBITS(h); \ 426 h=HBITS(h); \ 427 mul64(l,h,(bl),(bh)); \ 428 \ 429 /* non-multiply part */ \ 430 l=(l+(c))&BN_MASK2; if (l < (c)) h++; \ 431 (c)=(r); \ 432 l=(l+(c))&BN_MASK2; if (l < (c)) h++; \ 433 (c)=h&BN_MASK2; \ 434 (r)=l; \ 435 } 436 437 #define mul(r,a,bl,bh,c) { \ 438 BN_ULONG l,h; \ 439 \ 440 h= (a); \ 441 l=LBITS(h); \ 442 h=HBITS(h); \ 443 mul64(l,h,(bl),(bh)); \ 444 \ 445 /* non-multiply part */ \ 446 l+=(c); if ((l&BN_MASK2) < (c)) h++; \ 447 (c)=h&BN_MASK2; \ 448 (r)=l&BN_MASK2; \ 449 } 450 #endif /* !BN_LLONG */ 451 452 void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, int nb); 453 void bn_mul_comba8(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b); 454 void bn_mul_comba4(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b); 455 void bn_sqr_normal(BN_ULONG *r, const BN_ULONG *a, int n, BN_ULONG *tmp); 456 void bn_sqr_comba8(BN_ULONG *r, const BN_ULONG *a); 457 void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a); 458 int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n); 459 int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, 460 int cl, int dl); 461 void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2, 462 int dna, int dnb, BN_ULONG *t); 463 void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, 464 int n, int tna, int tnb, BN_ULONG *t); 465 void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t); 466 void bn_mul_low_normal(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n); 467 void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2, 468 BN_ULONG *t); 469 void bn_mul_high(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, BN_ULONG *l, int n2, 470 BN_ULONG *t); 471 BN_ULONG bn_add_part_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, 472 int cl, int dl); 473 BN_ULONG bn_sub_part_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b, 474 int cl, int dl); 475 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); 476 477 #define bn_wexpand(a,words) (((words) <= (a)->dmax)?(a):bn_expand2((a),(words))) 478 BIGNUM *bn_expand2(BIGNUM *a, int words); 479 BIGNUM *bn_expand(BIGNUM *a, int bits); 480 481 BIGNUM *bn_dup_expand(const BIGNUM *a, int words); /* unused */ 482 483 /* Bignum consistency macros 484 * There is one "API" macro, bn_fix_top(), for stripping leading zeroes from 485 * bignum data after direct manipulations on the data. There is also an 486 * "internal" macro, bn_check_top(), for verifying that there are no leading 487 * zeroes. Unfortunately, some auditing is required due to the fact that 488 * bn_fix_top() has become an overabused duct-tape because bignum data is 489 * occasionally passed around in an inconsistent state. So the following 490 * changes have been made to sort this out; 491 * - bn_fix_top()s implementation has been moved to bn_correct_top() 492 * - if BN_DEBUG isn't defined, bn_fix_top() maps to bn_correct_top(), and 493 * bn_check_top() is as before. 494 * - if BN_DEBUG *is* defined; 495 * - bn_check_top() tries to pollute unused words even if the bignum 'top' is 496 * consistent. (ed: only if BN_DEBUG_RAND is defined) 497 * - bn_fix_top() maps to bn_check_top() rather than "fixing" anything. 498 * The idea is to have debug builds flag up inconsistent bignums when they 499 * occur. If that occurs in a bn_fix_top(), we examine the code in question; if 500 * the use of bn_fix_top() was appropriate (ie. it follows directly after code 501 * that manipulates the bignum) it is converted to bn_correct_top(), and if it 502 * was not appropriate, we convert it permanently to bn_check_top() and track 503 * down the cause of the bug. Eventually, no internal code should be using the 504 * bn_fix_top() macro. External applications and libraries should try this with 505 * their own code too, both in terms of building against the openssl headers 506 * with BN_DEBUG defined *and* linking with a version of OpenSSL built with it 507 * defined. This not only improves external code, it provides more test 508 * coverage for openssl's own code. 509 */ 510 511 #ifdef BN_DEBUG 512 513 /* We only need assert() when debugging */ 514 #include <assert.h> 515 516 #ifdef BN_DEBUG_RAND 517 #define bn_pollute(a) \ 518 do { \ 519 const BIGNUM *_bnum1 = (a); \ 520 if(_bnum1->top < _bnum1->dmax) { \ 521 unsigned char _tmp_char; \ 522 /* We cast away const without the compiler knowing, any \ 523 * *genuinely* constant variables that aren't mutable \ 524 * wouldn't be constructed with top!=dmax. */ \ 525 BN_ULONG *_not_const; \ 526 memcpy(&_not_const, &_bnum1->d, sizeof(BN_ULONG*)); \ 527 arc4random_buf(&_tmp_char, 1); \ 528 memset((unsigned char *)(_not_const + _bnum1->top), _tmp_char, \ 529 (_bnum1->dmax - _bnum1->top) * sizeof(BN_ULONG)); \ 530 } \ 531 } while(0) 532 #else 533 #define bn_pollute(a) 534 #endif 535 536 #define bn_check_top(a) \ 537 do { \ 538 const BIGNUM *_bnum2 = (a); \ 539 if (_bnum2 != NULL) { \ 540 assert((_bnum2->top == 0) || \ 541 (_bnum2->d[_bnum2->top - 1] != 0)); \ 542 bn_pollute(_bnum2); \ 543 } \ 544 } while(0) 545 546 #define bn_fix_top(a) bn_check_top(a) 547 548 #define bn_check_size(bn, bits) bn_wcheck_size(bn, ((bits+BN_BITS2-1))/BN_BITS2) 549 #define bn_wcheck_size(bn, words) \ 550 do { \ 551 const BIGNUM *_bnum2 = (bn); \ 552 assert(words <= (_bnum2)->dmax && words >= (_bnum2)->top); \ 553 } while(0) 554 555 #else /* !BN_DEBUG */ 556 557 #define bn_pollute(a) 558 #define bn_check_top(a) 559 #define bn_fix_top(a) bn_correct_top(a) 560 #define bn_check_size(bn, bits) 561 #define bn_wcheck_size(bn, words) 562 563 #endif 564 565 #define bn_correct_top(a) \ 566 { \ 567 BN_ULONG *ftl; \ 568 int tmp_top = (a)->top; \ 569 if (tmp_top > 0) \ 570 { \ 571 for (ftl= &((a)->d[tmp_top-1]); tmp_top > 0; tmp_top--) \ 572 if (*(ftl--)) break; \ 573 (a)->top = tmp_top; \ 574 } \ 575 bn_pollute(a); \ 576 } 577 578 BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w); 579 BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, int num, BN_ULONG w); 580 void bn_sqr_words(BN_ULONG *rp, const BN_ULONG *ap, int num); 581 BN_ULONG bn_div_words(BN_ULONG h, BN_ULONG l, BN_ULONG d); 582 BN_ULONG bn_add_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, int num); 583 BN_ULONG bn_sub_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp, int num); 584 585 int BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom); 586 int bn_rand_interval(BIGNUM *rnd, const BIGNUM *lower_inc, const BIGNUM *upper_exc); 587 588 /* Explicitly const time / non-const time versions for internal use */ 589 int BN_mod_exp_ct(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 590 const BIGNUM *m, BN_CTX *ctx); 591 int BN_mod_exp_nonct(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 592 const BIGNUM *m, BN_CTX *ctx); 593 int BN_mod_exp_mont_ct(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 594 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx); 595 int BN_mod_exp_mont_nonct(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 596 const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx); 597 int BN_div_nonct(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, 598 BN_CTX *ctx); 599 int BN_div_ct(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d, 600 BN_CTX *ctx); 601 #define BN_mod_ct(rem,m,d,ctx) BN_div_ct(NULL,(rem),(m),(d),(ctx)) 602 #define BN_mod_nonct(rem,m,d,ctx) BN_div_nonct(NULL,(rem),(m),(d),(ctx)) 603 BIGNUM *BN_mod_inverse_ct(BIGNUM *ret, const BIGNUM *a, const BIGNUM *n, 604 BN_CTX *ctx); 605 BIGNUM *BN_mod_inverse_nonct(BIGNUM *ret, const BIGNUM *a, const BIGNUM *n, 606 BN_CTX *ctx); 607 int BN_gcd_ct(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx); 608 int BN_gcd_nonct(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx); 609 610 int BN_swap_ct(BN_ULONG swap, BIGNUM *a, BIGNUM *b, size_t nwords); 611 612 __END_HIDDEN_DECLS 613 #endif 614