1 /* Copyright (C) 1995-1997 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] 56 */ 57 /* ==================================================================== 58 * Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved. 59 * 60 * Redistribution and use in source and binary forms, with or without 61 * modification, are permitted provided that the following conditions 62 * are met: 63 * 64 * 1. Redistributions of source code must retain the above copyright 65 * notice, this list of conditions and the following disclaimer. 66 * 67 * 2. Redistributions in binary form must reproduce the above copyright 68 * notice, this list of conditions and the following disclaimer in 69 * the documentation and/or other materials provided with the 70 * distribution. 71 * 72 * 3. All advertising materials mentioning features or use of this 73 * software must display the following acknowledgment: 74 * "This product includes software developed by the OpenSSL Project 75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 76 * 77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 78 * endorse or promote products derived from this software without 79 * prior written permission. For written permission, please contact 80 * openssl-core (at) openssl.org. 81 * 82 * 5. Products derived from this software may not be called "OpenSSL" 83 * nor may "OpenSSL" appear in their names without prior written 84 * permission of the OpenSSL Project. 85 * 86 * 6. Redistributions of any form whatsoever must retain the following 87 * acknowledgment: 88 * "This product includes software developed by the OpenSSL Project 89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 90 * 91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 102 * OF THE POSSIBILITY OF SUCH DAMAGE. 103 * ==================================================================== 104 * 105 * This product includes cryptographic software written by Eric Young 106 * (eay (at) cryptsoft.com). This product includes software written by Tim 107 * Hudson (tjh (at) cryptsoft.com). 108 * 109 */ 110 /* ==================================================================== 111 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 112 * 113 * Portions of the attached software ("Contribution") are developed by 114 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. 115 * 116 * The Contribution is licensed pursuant to the Eric Young open source 117 * license provided above. 118 * 119 * The binary polynomial arithmetic software is originally written by 120 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems 121 * Laboratories. */ 122 123 #ifndef OPENSSL_HEADER_BN_H 124 #define OPENSSL_HEADER_BN_H 125 126 #include <openssl/base.h> 127 #include <openssl/thread.h> 128 129 #include <inttypes.h> // for PRIu64 and friends 130 #include <stdio.h> // for FILE* 131 132 #if defined(__cplusplus) 133 extern "C" { 134 #endif 135 136 137 // BN provides support for working with arbitrary sized integers. For example, 138 // although the largest integer supported by the compiler might be 64 bits, BN 139 // will allow you to work with numbers until you run out of memory. 140 141 142 // BN_ULONG is the native word size when working with big integers. 143 // 144 // Note: on some platforms, inttypes.h does not define print format macros in 145 // C++ unless |__STDC_FORMAT_MACROS| defined. As this is a public header, bn.h 146 // does not define |__STDC_FORMAT_MACROS| itself. C++ source files which use the 147 // FMT macros must define it externally. 148 #if defined(OPENSSL_64_BIT) 149 #define BN_ULONG uint64_t 150 #define BN_BITS2 64 151 #define BN_DEC_FMT1 "%" PRIu64 152 #define BN_DEC_FMT2 "%019" PRIu64 153 #define BN_HEX_FMT1 "%" PRIx64 154 #define BN_HEX_FMT2 "%016" PRIx64 155 #elif defined(OPENSSL_32_BIT) 156 #define BN_ULONG uint32_t 157 #define BN_BITS2 32 158 #define BN_DEC_FMT1 "%" PRIu32 159 #define BN_DEC_FMT2 "%09" PRIu32 160 #define BN_HEX_FMT1 "%" PRIx32 161 #define BN_HEX_FMT2 "%08" PRIx64 162 #else 163 #error "Must define either OPENSSL_32_BIT or OPENSSL_64_BIT" 164 #endif 165 166 167 // Allocation and freeing. 168 169 // BN_new creates a new, allocated BIGNUM and initialises it. 170 OPENSSL_EXPORT BIGNUM *BN_new(void); 171 172 // BN_init initialises a stack allocated |BIGNUM|. 173 OPENSSL_EXPORT void BN_init(BIGNUM *bn); 174 175 // BN_free frees the data referenced by |bn| and, if |bn| was originally 176 // allocated on the heap, frees |bn| also. 177 OPENSSL_EXPORT void BN_free(BIGNUM *bn); 178 179 // BN_clear_free erases and frees the data referenced by |bn| and, if |bn| was 180 // originally allocated on the heap, frees |bn| also. 181 OPENSSL_EXPORT void BN_clear_free(BIGNUM *bn); 182 183 // BN_dup allocates a new BIGNUM and sets it equal to |src|. It returns the 184 // allocated BIGNUM on success or NULL otherwise. 185 OPENSSL_EXPORT BIGNUM *BN_dup(const BIGNUM *src); 186 187 // BN_copy sets |dest| equal to |src| and returns |dest| or NULL on allocation 188 // failure. 189 OPENSSL_EXPORT BIGNUM *BN_copy(BIGNUM *dest, const BIGNUM *src); 190 191 // BN_clear sets |bn| to zero and erases the old data. 192 OPENSSL_EXPORT void BN_clear(BIGNUM *bn); 193 194 // BN_value_one returns a static BIGNUM with value 1. 195 OPENSSL_EXPORT const BIGNUM *BN_value_one(void); 196 197 198 // Basic functions. 199 200 // BN_num_bits returns the minimum number of bits needed to represent the 201 // absolute value of |bn|. 202 OPENSSL_EXPORT unsigned BN_num_bits(const BIGNUM *bn); 203 204 // BN_num_bytes returns the minimum number of bytes needed to represent the 205 // absolute value of |bn|. 206 OPENSSL_EXPORT unsigned BN_num_bytes(const BIGNUM *bn); 207 208 // BN_zero sets |bn| to zero. 209 OPENSSL_EXPORT void BN_zero(BIGNUM *bn); 210 211 // BN_one sets |bn| to one. It returns one on success or zero on allocation 212 // failure. 213 OPENSSL_EXPORT int BN_one(BIGNUM *bn); 214 215 // BN_set_word sets |bn| to |value|. It returns one on success or zero on 216 // allocation failure. 217 OPENSSL_EXPORT int BN_set_word(BIGNUM *bn, BN_ULONG value); 218 219 // BN_set_u64 sets |bn| to |value|. It returns one on success or zero on 220 // allocation failure. 221 OPENSSL_EXPORT int BN_set_u64(BIGNUM *bn, uint64_t value); 222 223 // BN_set_negative sets the sign of |bn|. 224 OPENSSL_EXPORT void BN_set_negative(BIGNUM *bn, int sign); 225 226 // BN_is_negative returns one if |bn| is negative and zero otherwise. 227 OPENSSL_EXPORT int BN_is_negative(const BIGNUM *bn); 228 229 230 // Conversion functions. 231 232 // BN_bin2bn sets |*ret| to the value of |len| bytes from |in|, interpreted as 233 // a big-endian number, and returns |ret|. If |ret| is NULL then a fresh 234 // |BIGNUM| is allocated and returned. It returns NULL on allocation 235 // failure. 236 OPENSSL_EXPORT BIGNUM *BN_bin2bn(const uint8_t *in, size_t len, BIGNUM *ret); 237 238 // BN_bn2bin serialises the absolute value of |in| to |out| as a big-endian 239 // integer, which must have |BN_num_bytes| of space available. It returns the 240 // number of bytes written. 241 OPENSSL_EXPORT size_t BN_bn2bin(const BIGNUM *in, uint8_t *out); 242 243 // BN_le2bn sets |*ret| to the value of |len| bytes from |in|, interpreted as 244 // a little-endian number, and returns |ret|. If |ret| is NULL then a fresh 245 // |BIGNUM| is allocated and returned. It returns NULL on allocation 246 // failure. 247 OPENSSL_EXPORT BIGNUM *BN_le2bn(const uint8_t *in, size_t len, BIGNUM *ret); 248 249 // BN_bn2le_padded serialises the absolute value of |in| to |out| as a 250 // little-endian integer, which must have |len| of space available, padding 251 // out the remainder of out with zeros. If |len| is smaller than |BN_num_bytes|, 252 // the function fails and returns 0. Otherwise, it returns 1. 253 OPENSSL_EXPORT int BN_bn2le_padded(uint8_t *out, size_t len, const BIGNUM *in); 254 255 // BN_bn2bin_padded serialises the absolute value of |in| to |out| as a 256 // big-endian integer. The integer is padded with leading zeros up to size 257 // |len|. If |len| is smaller than |BN_num_bytes|, the function fails and 258 // returns 0. Otherwise, it returns 1. 259 OPENSSL_EXPORT int BN_bn2bin_padded(uint8_t *out, size_t len, const BIGNUM *in); 260 261 // BN_bn2cbb_padded behaves like |BN_bn2bin_padded| but writes to a |CBB|. 262 OPENSSL_EXPORT int BN_bn2cbb_padded(CBB *out, size_t len, const BIGNUM *in); 263 264 // BN_bn2hex returns an allocated string that contains a NUL-terminated, hex 265 // representation of |bn|. If |bn| is negative, the first char in the resulting 266 // string will be '-'. Returns NULL on allocation failure. 267 OPENSSL_EXPORT char *BN_bn2hex(const BIGNUM *bn); 268 269 // BN_hex2bn parses the leading hex number from |in|, which may be proceeded by 270 // a '-' to indicate a negative number and may contain trailing, non-hex data. 271 // If |outp| is not NULL, it constructs a BIGNUM equal to the hex number and 272 // stores it in |*outp|. If |*outp| is NULL then it allocates a new BIGNUM and 273 // updates |*outp|. It returns the number of bytes of |in| processed or zero on 274 // error. 275 OPENSSL_EXPORT int BN_hex2bn(BIGNUM **outp, const char *in); 276 277 // BN_bn2dec returns an allocated string that contains a NUL-terminated, 278 // decimal representation of |bn|. If |bn| is negative, the first char in the 279 // resulting string will be '-'. Returns NULL on allocation failure. 280 OPENSSL_EXPORT char *BN_bn2dec(const BIGNUM *a); 281 282 // BN_dec2bn parses the leading decimal number from |in|, which may be 283 // proceeded by a '-' to indicate a negative number and may contain trailing, 284 // non-decimal data. If |outp| is not NULL, it constructs a BIGNUM equal to the 285 // decimal number and stores it in |*outp|. If |*outp| is NULL then it 286 // allocates a new BIGNUM and updates |*outp|. It returns the number of bytes 287 // of |in| processed or zero on error. 288 OPENSSL_EXPORT int BN_dec2bn(BIGNUM **outp, const char *in); 289 290 // BN_asc2bn acts like |BN_dec2bn| or |BN_hex2bn| depending on whether |in| 291 // begins with "0X" or "0x" (indicating hex) or not (indicating decimal). A 292 // leading '-' is still permitted and comes before the optional 0X/0x. It 293 // returns one on success or zero on error. 294 OPENSSL_EXPORT int BN_asc2bn(BIGNUM **outp, const char *in); 295 296 // BN_print writes a hex encoding of |a| to |bio|. It returns one on success 297 // and zero on error. 298 OPENSSL_EXPORT int BN_print(BIO *bio, const BIGNUM *a); 299 300 // BN_print_fp acts like |BIO_print|, but wraps |fp| in a |BIO| first. 301 OPENSSL_EXPORT int BN_print_fp(FILE *fp, const BIGNUM *a); 302 303 // BN_get_word returns the absolute value of |bn| as a single word. If |bn| is 304 // too large to be represented as a single word, the maximum possible value 305 // will be returned. 306 OPENSSL_EXPORT BN_ULONG BN_get_word(const BIGNUM *bn); 307 308 // BN_get_u64 sets |*out| to the absolute value of |bn| as a |uint64_t| and 309 // returns one. If |bn| is too large to be represented as a |uint64_t|, it 310 // returns zero. 311 OPENSSL_EXPORT int BN_get_u64(const BIGNUM *bn, uint64_t *out); 312 313 314 // ASN.1 functions. 315 316 // BN_parse_asn1_unsigned parses a non-negative DER INTEGER from |cbs| writes 317 // the result to |ret|. It returns one on success and zero on failure. 318 OPENSSL_EXPORT int BN_parse_asn1_unsigned(CBS *cbs, BIGNUM *ret); 319 320 // BN_marshal_asn1 marshals |bn| as a non-negative DER INTEGER and appends the 321 // result to |cbb|. It returns one on success and zero on failure. 322 OPENSSL_EXPORT int BN_marshal_asn1(CBB *cbb, const BIGNUM *bn); 323 324 325 // BIGNUM pools. 326 // 327 // Certain BIGNUM operations need to use many temporary variables and 328 // allocating and freeing them can be quite slow. Thus such operations typically 329 // take a |BN_CTX| parameter, which contains a pool of |BIGNUMs|. The |ctx| 330 // argument to a public function may be NULL, in which case a local |BN_CTX| 331 // will be created just for the lifetime of that call. 332 // 333 // A function must call |BN_CTX_start| first. Then, |BN_CTX_get| may be called 334 // repeatedly to obtain temporary |BIGNUM|s. All |BN_CTX_get| calls must be made 335 // before calling any other functions that use the |ctx| as an argument. 336 // 337 // Finally, |BN_CTX_end| must be called before returning from the function. 338 // When |BN_CTX_end| is called, the |BIGNUM| pointers obtained from 339 // |BN_CTX_get| become invalid. 340 341 // BN_CTX_new returns a new, empty BN_CTX or NULL on allocation failure. 342 OPENSSL_EXPORT BN_CTX *BN_CTX_new(void); 343 344 // BN_CTX_free frees all BIGNUMs contained in |ctx| and then frees |ctx| 345 // itself. 346 OPENSSL_EXPORT void BN_CTX_free(BN_CTX *ctx); 347 348 // BN_CTX_start "pushes" a new entry onto the |ctx| stack and allows future 349 // calls to |BN_CTX_get|. 350 OPENSSL_EXPORT void BN_CTX_start(BN_CTX *ctx); 351 352 // BN_CTX_get returns a new |BIGNUM|, or NULL on allocation failure. Once 353 // |BN_CTX_get| has returned NULL, all future calls will also return NULL until 354 // |BN_CTX_end| is called. 355 OPENSSL_EXPORT BIGNUM *BN_CTX_get(BN_CTX *ctx); 356 357 // BN_CTX_end invalidates all |BIGNUM|s returned from |BN_CTX_get| since the 358 // matching |BN_CTX_start| call. 359 OPENSSL_EXPORT void BN_CTX_end(BN_CTX *ctx); 360 361 362 // Simple arithmetic 363 364 // BN_add sets |r| = |a| + |b|, where |r| may be the same pointer as either |a| 365 // or |b|. It returns one on success and zero on allocation failure. 366 OPENSSL_EXPORT int BN_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); 367 368 // BN_uadd sets |r| = |a| + |b|, where |a| and |b| are non-negative and |r| may 369 // be the same pointer as either |a| or |b|. It returns one on success and zero 370 // on allocation failure. 371 OPENSSL_EXPORT int BN_uadd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); 372 373 // BN_add_word adds |w| to |a|. It returns one on success and zero otherwise. 374 OPENSSL_EXPORT int BN_add_word(BIGNUM *a, BN_ULONG w); 375 376 // BN_sub sets |r| = |a| - |b|, where |r| may be the same pointer as either |a| 377 // or |b|. It returns one on success and zero on allocation failure. 378 OPENSSL_EXPORT int BN_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); 379 380 // BN_usub sets |r| = |a| - |b|, where |a| and |b| are non-negative integers, 381 // |b| < |a| and |r| may be the same pointer as either |a| or |b|. It returns 382 // one on success and zero on allocation failure. 383 OPENSSL_EXPORT int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); 384 385 // BN_sub_word subtracts |w| from |a|. It returns one on success and zero on 386 // allocation failure. 387 OPENSSL_EXPORT int BN_sub_word(BIGNUM *a, BN_ULONG w); 388 389 // BN_mul sets |r| = |a| * |b|, where |r| may be the same pointer as |a| or 390 // |b|. Returns one on success and zero otherwise. 391 OPENSSL_EXPORT int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 392 BN_CTX *ctx); 393 394 // BN_mul_word sets |bn| = |bn| * |w|. It returns one on success or zero on 395 // allocation failure. 396 OPENSSL_EXPORT int BN_mul_word(BIGNUM *bn, BN_ULONG w); 397 398 // BN_sqr sets |r| = |a|^2 (i.e. squares), where |r| may be the same pointer as 399 // |a|. Returns one on success and zero otherwise. This is more efficient than 400 // BN_mul(r, a, a, ctx). 401 OPENSSL_EXPORT int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx); 402 403 // BN_div divides |numerator| by |divisor| and places the result in |quotient| 404 // and the remainder in |rem|. Either of |quotient| or |rem| may be NULL, in 405 // which case the respective value is not returned. The result is rounded 406 // towards zero; thus if |numerator| is negative, the remainder will be zero or 407 // negative. It returns one on success or zero on error. 408 OPENSSL_EXPORT int BN_div(BIGNUM *quotient, BIGNUM *rem, 409 const BIGNUM *numerator, const BIGNUM *divisor, 410 BN_CTX *ctx); 411 412 // BN_div_word sets |numerator| = |numerator|/|divisor| and returns the 413 // remainder or (BN_ULONG)-1 on error. 414 OPENSSL_EXPORT BN_ULONG BN_div_word(BIGNUM *numerator, BN_ULONG divisor); 415 416 // BN_sqrt sets |*out_sqrt| (which may be the same |BIGNUM| as |in|) to the 417 // square root of |in|, using |ctx|. It returns one on success or zero on 418 // error. Negative numbers and non-square numbers will result in an error with 419 // appropriate errors on the error queue. 420 OPENSSL_EXPORT int BN_sqrt(BIGNUM *out_sqrt, const BIGNUM *in, BN_CTX *ctx); 421 422 423 // Comparison functions 424 425 // BN_cmp returns a value less than, equal to or greater than zero if |a| is 426 // less than, equal to or greater than |b|, respectively. 427 OPENSSL_EXPORT int BN_cmp(const BIGNUM *a, const BIGNUM *b); 428 429 // BN_cmp_word is like |BN_cmp| except it takes its second argument as a 430 // |BN_ULONG| instead of a |BIGNUM|. 431 OPENSSL_EXPORT int BN_cmp_word(const BIGNUM *a, BN_ULONG b); 432 433 // BN_ucmp returns a value less than, equal to or greater than zero if the 434 // absolute value of |a| is less than, equal to or greater than the absolute 435 // value of |b|, respectively. 436 OPENSSL_EXPORT int BN_ucmp(const BIGNUM *a, const BIGNUM *b); 437 438 // BN_equal_consttime returns one if |a| is equal to |b|, and zero otherwise. 439 // It takes an amount of time dependent on the sizes of |a| and |b|, but 440 // independent of the contents (including the signs) of |a| and |b|. 441 OPENSSL_EXPORT int BN_equal_consttime(const BIGNUM *a, const BIGNUM *b); 442 443 // BN_less_than_consttime returns one if |a| is less than |b|, and zero 444 // otherwise. It takes an amount of time dependent on the sizes and signs of |a| 445 // and |b|, but independent of the contents of |a| and |b|. 446 OPENSSL_EXPORT int BN_less_than_consttime(const BIGNUM *a, const BIGNUM *b); 447 448 // BN_abs_is_word returns one if the absolute value of |bn| equals |w| and zero 449 // otherwise. 450 OPENSSL_EXPORT int BN_abs_is_word(const BIGNUM *bn, BN_ULONG w); 451 452 // BN_is_zero returns one if |bn| is zero and zero otherwise. 453 OPENSSL_EXPORT int BN_is_zero(const BIGNUM *bn); 454 455 // BN_is_one returns one if |bn| equals one and zero otherwise. 456 OPENSSL_EXPORT int BN_is_one(const BIGNUM *bn); 457 458 // BN_is_word returns one if |bn| is exactly |w| and zero otherwise. 459 OPENSSL_EXPORT int BN_is_word(const BIGNUM *bn, BN_ULONG w); 460 461 // BN_is_odd returns one if |bn| is odd and zero otherwise. 462 OPENSSL_EXPORT int BN_is_odd(const BIGNUM *bn); 463 464 // BN_is_pow2 returns 1 if |a| is a power of two, and 0 otherwise. 465 OPENSSL_EXPORT int BN_is_pow2(const BIGNUM *a); 466 467 // Bitwise operations. 468 469 // BN_lshift sets |r| equal to |a| << n. The |a| and |r| arguments may be the 470 // same |BIGNUM|. It returns one on success and zero on allocation failure. 471 OPENSSL_EXPORT int BN_lshift(BIGNUM *r, const BIGNUM *a, int n); 472 473 // BN_lshift1 sets |r| equal to |a| << 1, where |r| and |a| may be the same 474 // pointer. It returns one on success and zero on allocation failure. 475 OPENSSL_EXPORT int BN_lshift1(BIGNUM *r, const BIGNUM *a); 476 477 // BN_rshift sets |r| equal to |a| >> n, where |r| and |a| may be the same 478 // pointer. It returns one on success and zero on allocation failure. 479 OPENSSL_EXPORT int BN_rshift(BIGNUM *r, const BIGNUM *a, int n); 480 481 // BN_rshift1 sets |r| equal to |a| >> 1, where |r| and |a| may be the same 482 // pointer. It returns one on success and zero on allocation failure. 483 OPENSSL_EXPORT int BN_rshift1(BIGNUM *r, const BIGNUM *a); 484 485 // BN_set_bit sets the |n|th, least-significant bit in |a|. For example, if |a| 486 // is 2 then setting bit zero will make it 3. It returns one on success or zero 487 // on allocation failure. 488 OPENSSL_EXPORT int BN_set_bit(BIGNUM *a, int n); 489 490 // BN_clear_bit clears the |n|th, least-significant bit in |a|. For example, if 491 // |a| is 3, clearing bit zero will make it two. It returns one on success or 492 // zero on allocation failure. 493 OPENSSL_EXPORT int BN_clear_bit(BIGNUM *a, int n); 494 495 // BN_is_bit_set returns one if the |n|th least-significant bit in |a| exists 496 // and is set. Otherwise, it returns zero. 497 OPENSSL_EXPORT int BN_is_bit_set(const BIGNUM *a, int n); 498 499 // BN_mask_bits truncates |a| so that it is only |n| bits long. It returns one 500 // on success or zero if |n| is greater than the length of |a| already. 501 OPENSSL_EXPORT int BN_mask_bits(BIGNUM *a, int n); 502 503 504 // Modulo arithmetic. 505 506 // BN_mod_word returns |a| mod |w| or (BN_ULONG)-1 on error. 507 OPENSSL_EXPORT BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w); 508 509 // BN_mod_pow2 sets |r| = |a| mod 2^|e|. It returns 1 on success and 510 // 0 on error. 511 OPENSSL_EXPORT int BN_mod_pow2(BIGNUM *r, const BIGNUM *a, size_t e); 512 513 // BN_nnmod_pow2 sets |r| = |a| mod 2^|e| where |r| is always positive. 514 // It returns 1 on success and 0 on error. 515 OPENSSL_EXPORT int BN_nnmod_pow2(BIGNUM *r, const BIGNUM *a, size_t e); 516 517 // BN_mod is a helper macro that calls |BN_div| and discards the quotient. 518 #define BN_mod(rem, numerator, divisor, ctx) \ 519 BN_div(NULL, (rem), (numerator), (divisor), (ctx)) 520 521 // BN_nnmod is a non-negative modulo function. It acts like |BN_mod|, but 0 <= 522 // |rem| < |divisor| is always true. It returns one on success and zero on 523 // error. 524 OPENSSL_EXPORT int BN_nnmod(BIGNUM *rem, const BIGNUM *numerator, 525 const BIGNUM *divisor, BN_CTX *ctx); 526 527 // BN_mod_add sets |r| = |a| + |b| mod |m|. It returns one on success and zero 528 // on error. 529 OPENSSL_EXPORT int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 530 const BIGNUM *m, BN_CTX *ctx); 531 532 // BN_mod_add_quick acts like |BN_mod_add| but requires that |a| and |b| be 533 // non-negative and less than |m|. 534 OPENSSL_EXPORT int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 535 const BIGNUM *m); 536 537 // BN_mod_sub sets |r| = |a| - |b| mod |m|. It returns one on success and zero 538 // on error. 539 OPENSSL_EXPORT int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 540 const BIGNUM *m, BN_CTX *ctx); 541 542 // BN_mod_sub_quick acts like |BN_mod_sub| but requires that |a| and |b| be 543 // non-negative and less than |m|. 544 OPENSSL_EXPORT int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 545 const BIGNUM *m); 546 547 // BN_mod_mul sets |r| = |a|*|b| mod |m|. It returns one on success and zero 548 // on error. 549 OPENSSL_EXPORT int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 550 const BIGNUM *m, BN_CTX *ctx); 551 552 // BN_mod_sqr sets |r| = |a|^2 mod |m|. It returns one on success and zero 553 // on error. 554 OPENSSL_EXPORT int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, 555 BN_CTX *ctx); 556 557 // BN_mod_lshift sets |r| = (|a| << n) mod |m|, where |r| and |a| may be the 558 // same pointer. It returns one on success and zero on error. 559 OPENSSL_EXPORT int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, 560 const BIGNUM *m, BN_CTX *ctx); 561 562 // BN_mod_lshift_quick acts like |BN_mod_lshift| but requires that |a| be 563 // non-negative and less than |m|. 564 OPENSSL_EXPORT int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, 565 const BIGNUM *m); 566 567 // BN_mod_lshift1 sets |r| = (|a| << 1) mod |m|, where |r| and |a| may be the 568 // same pointer. It returns one on success and zero on error. 569 OPENSSL_EXPORT int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, 570 BN_CTX *ctx); 571 572 // BN_mod_lshift1_quick acts like |BN_mod_lshift1| but requires that |a| be 573 // non-negative and less than |m|. 574 OPENSSL_EXPORT int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, 575 const BIGNUM *m); 576 577 // BN_mod_sqrt returns a newly-allocated |BIGNUM|, r, such that 578 // r^2 == a (mod p). |p| must be a prime. It returns NULL on error or if |a| is 579 // not a square mod |p|. In the latter case, it will add |BN_R_NOT_A_SQUARE| to 580 // the error queue. 581 OPENSSL_EXPORT BIGNUM *BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, 582 BN_CTX *ctx); 583 584 585 // Random and prime number generation. 586 587 // The following are values for the |top| parameter of |BN_rand|. 588 #define BN_RAND_TOP_ANY (-1) 589 #define BN_RAND_TOP_ONE 0 590 #define BN_RAND_TOP_TWO 1 591 592 // The following are values for the |bottom| parameter of |BN_rand|. 593 #define BN_RAND_BOTTOM_ANY 0 594 #define BN_RAND_BOTTOM_ODD 1 595 596 // BN_rand sets |rnd| to a random number of length |bits|. It returns one on 597 // success and zero otherwise. 598 // 599 // |top| must be one of the |BN_RAND_TOP_*| values. If |BN_RAND_TOP_ONE|, the 600 // most-significant bit, if any, will be set. If |BN_RAND_TOP_TWO|, the two 601 // most significant bits, if any, will be set. If |BN_RAND_TOP_ANY|, no extra 602 // action will be taken and |BN_num_bits(rnd)| may not equal |bits| if the most 603 // significant bits randomly ended up as zeros. 604 // 605 // |bottom| must be one of the |BN_RAND_BOTTOM_*| values. If 606 // |BN_RAND_BOTTOM_ODD|, the least-significant bit, if any, will be set. If 607 // |BN_RAND_BOTTOM_ANY|, no extra action will be taken. 608 OPENSSL_EXPORT int BN_rand(BIGNUM *rnd, int bits, int top, int bottom); 609 610 // BN_pseudo_rand is an alias for |BN_rand|. 611 OPENSSL_EXPORT int BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom); 612 613 // BN_rand_range is equivalent to |BN_rand_range_ex| with |min_inclusive| set 614 // to zero and |max_exclusive| set to |range|. 615 OPENSSL_EXPORT int BN_rand_range(BIGNUM *rnd, const BIGNUM *range); 616 617 // BN_rand_range_ex sets |rnd| to a random value in 618 // [min_inclusive..max_exclusive). It returns one on success and zero 619 // otherwise. 620 OPENSSL_EXPORT int BN_rand_range_ex(BIGNUM *r, BN_ULONG min_inclusive, 621 const BIGNUM *max_exclusive); 622 623 // BN_pseudo_rand_range is an alias for BN_rand_range. 624 OPENSSL_EXPORT int BN_pseudo_rand_range(BIGNUM *rnd, const BIGNUM *range); 625 626 // BN_GENCB holds a callback function that is used by generation functions that 627 // can take a very long time to complete. Use |BN_GENCB_set| to initialise a 628 // |BN_GENCB| structure. 629 // 630 // The callback receives the address of that |BN_GENCB| structure as its last 631 // argument and the user is free to put an arbitrary pointer in |arg|. The other 632 // arguments are set as follows: 633 // event=BN_GENCB_GENERATED, n=i: after generating the i'th possible prime 634 // number. 635 // event=BN_GENCB_PRIME_TEST, n=-1: when finished trial division primality 636 // checks. 637 // event=BN_GENCB_PRIME_TEST, n=i: when the i'th primality test has finished. 638 // 639 // The callback can return zero to abort the generation progress or one to 640 // allow it to continue. 641 // 642 // When other code needs to call a BN generation function it will often take a 643 // BN_GENCB argument and may call the function with other argument values. 644 #define BN_GENCB_GENERATED 0 645 #define BN_GENCB_PRIME_TEST 1 646 647 struct bn_gencb_st { 648 void *arg; // callback-specific data 649 int (*callback)(int event, int n, struct bn_gencb_st *); 650 }; 651 652 // BN_GENCB_set configures |callback| to call |f| and sets |callout->arg| to 653 // |arg|. 654 OPENSSL_EXPORT void BN_GENCB_set(BN_GENCB *callback, 655 int (*f)(int event, int n, 656 struct bn_gencb_st *), 657 void *arg); 658 659 // BN_GENCB_call calls |callback|, if not NULL, and returns the return value of 660 // the callback, or 1 if |callback| is NULL. 661 OPENSSL_EXPORT int BN_GENCB_call(BN_GENCB *callback, int event, int n); 662 663 // BN_generate_prime_ex sets |ret| to a prime number of |bits| length. If safe 664 // is non-zero then the prime will be such that (ret-1)/2 is also a prime. 665 // (This is needed for Diffie-Hellman groups to ensure that the only subgroups 666 // are of size 2 and (p-1)/2.). 667 // 668 // If |add| is not NULL, the prime will fulfill the condition |ret| % |add| == 669 // |rem| in order to suit a given generator. (If |rem| is NULL then |ret| % 670 // |add| == 1.) 671 // 672 // If |cb| is not NULL, it will be called during processing to give an 673 // indication of progress. See the comments for |BN_GENCB|. It returns one on 674 // success and zero otherwise. 675 OPENSSL_EXPORT int BN_generate_prime_ex(BIGNUM *ret, int bits, int safe, 676 const BIGNUM *add, const BIGNUM *rem, 677 BN_GENCB *cb); 678 679 // BN_prime_checks is magic value that can be used as the |checks| argument to 680 // the primality testing functions in order to automatically select a number of 681 // Miller-Rabin checks that gives a false positive rate of ~2^{-80}. 682 #define BN_prime_checks 0 683 684 // bn_primality_result_t enumerates the outcomes of primality-testing. 685 enum bn_primality_result_t { 686 bn_probably_prime, 687 bn_composite, 688 bn_non_prime_power_composite, 689 }; 690 691 // BN_enhanced_miller_rabin_primality_test tests whether |w| is probably a prime 692 // number using the Enhanced Miller-Rabin Test (FIPS 186-4 C.3.2) with 693 // |iterations| iterations and returns the result in |out_result|. Enhanced 694 // Miller-Rabin tests primality for odd integers greater than 3, returning 695 // |bn_probably_prime| if the number is probably prime, 696 // |bn_non_prime_power_composite| if the number is a composite that is not the 697 // power of a single prime, and |bn_composite| otherwise. If |iterations| is 698 // |BN_prime_checks|, then a value that results in a false positive rate lower 699 // than the number-field sieve security level of |w| is used. It returns one on 700 // success and zero on failure. If |cb| is not NULL, then it is called during 701 // each iteration of the primality test. 702 int BN_enhanced_miller_rabin_primality_test( 703 enum bn_primality_result_t *out_result, const BIGNUM *w, int iterations, 704 BN_CTX *ctx, BN_GENCB *cb); 705 706 // BN_primality_test sets |*is_probably_prime| to one if |candidate| is 707 // probably a prime number by the Miller-Rabin test or zero if it's certainly 708 // not. 709 // 710 // If |do_trial_division| is non-zero then |candidate| will be tested against a 711 // list of small primes before Miller-Rabin tests. The probability of this 712 // function returning a false positive is 2^{2*checks}. If |checks| is 713 // |BN_prime_checks| then a value that results in a false positive rate lower 714 // than the number-field sieve security level of |candidate| is used. If |cb| is 715 // not NULL then it is called during the checking process. See the comment above 716 // |BN_GENCB|. 717 // 718 // The function returns one on success and zero on error. 719 // 720 // (If you are unsure whether you want |do_trial_division|, don't set it.) 721 OPENSSL_EXPORT int BN_primality_test(int *is_probably_prime, 722 const BIGNUM *candidate, int checks, 723 BN_CTX *ctx, int do_trial_division, 724 BN_GENCB *cb); 725 726 // BN_is_prime_fasttest_ex returns one if |candidate| is probably a prime 727 // number by the Miller-Rabin test, zero if it's certainly not and -1 on error. 728 // 729 // If |do_trial_division| is non-zero then |candidate| will be tested against a 730 // list of small primes before Miller-Rabin tests. The probability of this 731 // function returning one when |candidate| is composite is 2^{2*checks}. If 732 // |checks| is |BN_prime_checks| then a value that results in a false positive 733 // rate lower than the number-field sieve security level of |candidate| is used. 734 // If |cb| is not NULL then it is called during the checking process. See the 735 // comment above |BN_GENCB|. 736 // 737 // WARNING: deprecated. Use |BN_primality_test|. 738 OPENSSL_EXPORT int BN_is_prime_fasttest_ex(const BIGNUM *candidate, int checks, 739 BN_CTX *ctx, int do_trial_division, 740 BN_GENCB *cb); 741 742 // BN_is_prime_ex acts the same as |BN_is_prime_fasttest_ex| with 743 // |do_trial_division| set to zero. 744 // 745 // WARNING: deprecated: Use |BN_primality_test|. 746 OPENSSL_EXPORT int BN_is_prime_ex(const BIGNUM *candidate, int checks, 747 BN_CTX *ctx, BN_GENCB *cb); 748 749 750 // Number theory functions 751 752 // BN_gcd sets |r| = gcd(|a|, |b|). It returns one on success and zero 753 // otherwise. 754 OPENSSL_EXPORT int BN_gcd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 755 BN_CTX *ctx); 756 757 // BN_mod_inverse sets |out| equal to |a|^-1, mod |n|. If |out| is NULL, a 758 // fresh BIGNUM is allocated. It returns the result or NULL on error. 759 // 760 // If |n| is even then the operation is performed using an algorithm that avoids 761 // some branches but which isn't constant-time. This function shouldn't be used 762 // for secret values; use |BN_mod_inverse_blinded| instead. Or, if |n| is 763 // guaranteed to be prime, use 764 // |BN_mod_exp_mont_consttime(out, a, m_minus_2, m, ctx, m_mont)|, taking 765 // advantage of Fermat's Little Theorem. 766 OPENSSL_EXPORT BIGNUM *BN_mod_inverse(BIGNUM *out, const BIGNUM *a, 767 const BIGNUM *n, BN_CTX *ctx); 768 769 // BN_mod_inverse_blinded sets |out| equal to |a|^-1, mod |n|, where |n| is the 770 // Montgomery modulus for |mont|. |a| must be non-negative and must be less 771 // than |n|. |n| must be greater than 1. |a| is blinded (masked by a random 772 // value) to protect it against side-channel attacks. On failure, if the failure 773 // was caused by |a| having no inverse mod |n| then |*out_no_inverse| will be 774 // set to one; otherwise it will be set to zero. 775 int BN_mod_inverse_blinded(BIGNUM *out, int *out_no_inverse, const BIGNUM *a, 776 const BN_MONT_CTX *mont, BN_CTX *ctx); 777 778 // BN_mod_inverse_odd sets |out| equal to |a|^-1, mod |n|. |a| must be 779 // non-negative and must be less than |n|. |n| must be odd. This function 780 // shouldn't be used for secret values; use |BN_mod_inverse_blinded| instead. 781 // Or, if |n| is guaranteed to be prime, use 782 // |BN_mod_exp_mont_consttime(out, a, m_minus_2, m, ctx, m_mont)|, taking 783 // advantage of Fermat's Little Theorem. It returns one on success or zero on 784 // failure. On failure, if the failure was caused by |a| having no inverse mod 785 // |n| then |*out_no_inverse| will be set to one; otherwise it will be set to 786 // zero. 787 int BN_mod_inverse_odd(BIGNUM *out, int *out_no_inverse, const BIGNUM *a, 788 const BIGNUM *n, BN_CTX *ctx); 789 790 791 // Montgomery arithmetic. 792 793 // BN_MONT_CTX contains the precomputed values needed to work in a specific 794 // Montgomery domain. 795 796 // BN_MONT_CTX_new_for_modulus returns a fresh |BN_MONT_CTX| given the modulus, 797 // |mod| or NULL on error. 798 OPENSSL_EXPORT BN_MONT_CTX *BN_MONT_CTX_new_for_modulus(const BIGNUM *mod, 799 BN_CTX *ctx); 800 801 // BN_MONT_CTX_free frees memory associated with |mont|. 802 OPENSSL_EXPORT void BN_MONT_CTX_free(BN_MONT_CTX *mont); 803 804 // BN_MONT_CTX_copy sets |to| equal to |from|. It returns |to| on success or 805 // NULL on error. 806 OPENSSL_EXPORT BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, 807 const BN_MONT_CTX *from); 808 809 // BN_MONT_CTX_set_locked takes |lock| and checks whether |*pmont| is NULL. If 810 // so, it creates a new |BN_MONT_CTX| and sets the modulus for it to |mod|. It 811 // then stores it as |*pmont|. It returns one on success and zero on error. 812 // 813 // If |*pmont| is already non-NULL then it does nothing and returns one. 814 int BN_MONT_CTX_set_locked(BN_MONT_CTX **pmont, CRYPTO_MUTEX *lock, 815 const BIGNUM *mod, BN_CTX *bn_ctx); 816 817 // BN_to_montgomery sets |ret| equal to |a| in the Montgomery domain. |a| is 818 // assumed to be in the range [0, n), where |n| is the Montgomery modulus. It 819 // returns one on success or zero on error. 820 OPENSSL_EXPORT int BN_to_montgomery(BIGNUM *ret, const BIGNUM *a, 821 const BN_MONT_CTX *mont, BN_CTX *ctx); 822 823 // BN_from_montgomery sets |ret| equal to |a| * R^-1, i.e. translates values out 824 // of the Montgomery domain. |a| is assumed to be in the range [0, n), where |n| 825 // is the Montgomery modulus. It returns one on success or zero on error. 826 OPENSSL_EXPORT int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, 827 const BN_MONT_CTX *mont, BN_CTX *ctx); 828 829 // BN_mod_mul_montgomery set |r| equal to |a| * |b|, in the Montgomery domain. 830 // Both |a| and |b| must already be in the Montgomery domain (by 831 // |BN_to_montgomery|). In particular, |a| and |b| are assumed to be in the 832 // range [0, n), where |n| is the Montgomery modulus. It returns one on success 833 // or zero on error. 834 OPENSSL_EXPORT int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, 835 const BIGNUM *b, 836 const BN_MONT_CTX *mont, BN_CTX *ctx); 837 838 839 // Exponentiation. 840 841 // BN_exp sets |r| equal to |a|^{|p|}. It does so with a square-and-multiply 842 // algorithm that leaks side-channel information. It returns one on success or 843 // zero otherwise. 844 OPENSSL_EXPORT int BN_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 845 BN_CTX *ctx); 846 847 // BN_mod_exp sets |r| equal to |a|^{|p|} mod |m|. It does so with the best 848 // algorithm for the values provided. It returns one on success or zero 849 // otherwise. The |BN_mod_exp_mont_consttime| variant must be used if the 850 // exponent is secret. 851 OPENSSL_EXPORT int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 852 const BIGNUM *m, BN_CTX *ctx); 853 854 OPENSSL_EXPORT int BN_mod_exp_mont(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, 855 const BIGNUM *m, BN_CTX *ctx, 856 const BN_MONT_CTX *mont); 857 858 OPENSSL_EXPORT int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, 859 const BIGNUM *p, const BIGNUM *m, 860 BN_CTX *ctx, 861 const BN_MONT_CTX *mont); 862 863 864 // Deprecated functions 865 866 // BN_bn2mpi serialises the value of |in| to |out|, using a format that consists 867 // of the number's length in bytes represented as a 4-byte big-endian number, 868 // and the number itself in big-endian format, where the most significant bit 869 // signals a negative number. (The representation of numbers with the MSB set is 870 // prefixed with null byte). |out| must have sufficient space available; to 871 // find the needed amount of space, call the function with |out| set to NULL. 872 OPENSSL_EXPORT size_t BN_bn2mpi(const BIGNUM *in, uint8_t *out); 873 874 // BN_mpi2bn parses |len| bytes from |in| and returns the resulting value. The 875 // bytes at |in| are expected to be in the format emitted by |BN_bn2mpi|. 876 // 877 // If |out| is NULL then a fresh |BIGNUM| is allocated and returned, otherwise 878 // |out| is reused and returned. On error, NULL is returned and the error queue 879 // is updated. 880 OPENSSL_EXPORT BIGNUM *BN_mpi2bn(const uint8_t *in, size_t len, BIGNUM *out); 881 882 // BN_mod_exp_mont_word is like |BN_mod_exp_mont| except that the base |a| is 883 // given as a |BN_ULONG| instead of a |BIGNUM *|. It returns one on success 884 // or zero otherwise. 885 OPENSSL_EXPORT int BN_mod_exp_mont_word(BIGNUM *r, BN_ULONG a, const BIGNUM *p, 886 const BIGNUM *m, BN_CTX *ctx, 887 const BN_MONT_CTX *mont); 888 889 // BN_mod_exp2_mont calculates (a1^p1) * (a2^p2) mod m. It returns 1 on success 890 // or zero otherwise. 891 OPENSSL_EXPORT int BN_mod_exp2_mont(BIGNUM *r, const BIGNUM *a1, 892 const BIGNUM *p1, const BIGNUM *a2, 893 const BIGNUM *p2, const BIGNUM *m, 894 BN_CTX *ctx, const BN_MONT_CTX *mont); 895 896 // BN_MONT_CTX_new returns a fresh |BN_MONT_CTX| or NULL on allocation failure. 897 // Use |BN_MONT_CTX_new_for_modulus| instead. 898 OPENSSL_EXPORT BN_MONT_CTX *BN_MONT_CTX_new(void); 899 900 // BN_MONT_CTX_set sets up a Montgomery context given the modulus, |mod|. It 901 // returns one on success and zero on error. Use |BN_MONT_CTX_new_for_modulus| 902 // instead. 903 OPENSSL_EXPORT int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, 904 BN_CTX *ctx); 905 906 907 // Private functions 908 909 struct bignum_st { 910 BN_ULONG *d; /* Pointer to an array of 'BN_BITS2' bit chunks in little-endian 911 order. */ 912 int top; // Index of last used element in |d|, plus one. 913 int dmax; // Size of |d|, in words. 914 int neg; // one if the number is negative 915 int flags; // bitmask of BN_FLG_* values 916 }; 917 918 struct bn_mont_ctx_st { 919 // RR is R^2, reduced modulo |N|. It is used to convert to Montgomery form. 920 BIGNUM RR; 921 // N is the modulus. It is always stored in minimal form, so |N.top| 922 // determines R. 923 BIGNUM N; 924 BN_ULONG n0[2]; // least significant words of (R*Ri-1)/N 925 }; 926 927 OPENSSL_EXPORT unsigned BN_num_bits_word(BN_ULONG l); 928 929 #define BN_FLG_MALLOCED 0x01 930 #define BN_FLG_STATIC_DATA 0x02 931 // |BN_FLG_CONSTTIME| has been removed and intentionally omitted so code relying 932 // on it will not compile. Consumers outside BoringSSL should use the 933 // higher-level cryptographic algorithms exposed by other modules. Consumers 934 // within the library should call the appropriate timing-sensitive algorithm 935 // directly. 936 937 938 #if defined(__cplusplus) 939 } // extern C 940 941 #if !defined(BORINGSSL_NO_CXX) 942 extern "C++" { 943 944 namespace bssl { 945 946 BORINGSSL_MAKE_DELETER(BIGNUM, BN_free) 947 BORINGSSL_MAKE_DELETER(BN_CTX, BN_CTX_free) 948 BORINGSSL_MAKE_DELETER(BN_MONT_CTX, BN_MONT_CTX_free) 949 950 class BN_CTXScope { 951 public: 952 BN_CTXScope(BN_CTX *ctx) : ctx_(ctx) { BN_CTX_start(ctx_); } 953 ~BN_CTXScope() { BN_CTX_end(ctx_); } 954 955 private: 956 BN_CTX *ctx_; 957 958 BN_CTXScope(BN_CTXScope &) = delete; 959 BN_CTXScope &operator=(BN_CTXScope &) = delete; 960 }; 961 962 } // namespace bssl 963 964 } // extern C++ 965 #endif 966 967 #endif 968 969 #define BN_R_ARG2_LT_ARG3 100 970 #define BN_R_BAD_RECIPROCAL 101 971 #define BN_R_BIGNUM_TOO_LONG 102 972 #define BN_R_BITS_TOO_SMALL 103 973 #define BN_R_CALLED_WITH_EVEN_MODULUS 104 974 #define BN_R_DIV_BY_ZERO 105 975 #define BN_R_EXPAND_ON_STATIC_BIGNUM_DATA 106 976 #define BN_R_INPUT_NOT_REDUCED 107 977 #define BN_R_INVALID_RANGE 108 978 #define BN_R_NEGATIVE_NUMBER 109 979 #define BN_R_NOT_A_SQUARE 110 980 #define BN_R_NOT_INITIALIZED 111 981 #define BN_R_NO_INVERSE 112 982 #define BN_R_PRIVATE_KEY_TOO_LARGE 113 983 #define BN_R_P_IS_NOT_PRIME 114 984 #define BN_R_TOO_MANY_ITERATIONS 115 985 #define BN_R_TOO_MANY_TEMPORARY_VARIABLES 116 986 #define BN_R_BAD_ENCODING 117 987 #define BN_R_ENCODE_ERROR 118 988 #define BN_R_INVALID_INPUT 119 989 990 #endif // OPENSSL_HEADER_BN_H 991