Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1 | /* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com) |
| 2 | * All rights reserved. |
| 3 | * |
| 4 | * This package is an SSL implementation written |
| 5 | * by Eric Young (eay@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@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@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@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@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@cryptsoft.com). This product includes software written by Tim |
| 107 | * Hudson (tjh@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> |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 127 | #include <openssl/thread.h> |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 128 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 129 | #include <inttypes.h> /* for PRIu64 and friends */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 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 arbitary 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 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 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. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 148 | #if defined(OPENSSL_64_BIT) |
| 149 | #define BN_ULONG uint64_t |
| 150 | #define BN_BITS2 64 |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 151 | #define BN_DEC_FMT1 "%" PRIu64 |
| 152 | #define BN_DEC_FMT2 "%019" PRIu64 |
| 153 | #define BN_HEX_FMT1 "%" PRIx64 |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 154 | #elif defined(OPENSSL_32_BIT) |
| 155 | #define BN_ULONG uint32_t |
| 156 | #define BN_BITS2 32 |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 157 | #define BN_DEC_FMT1 "%" PRIu32 |
| 158 | #define BN_DEC_FMT2 "%09" PRIu32 |
| 159 | #define BN_HEX_FMT1 "%" PRIx32 |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 160 | #else |
| 161 | #error "Must define either OPENSSL_32_BIT or OPENSSL_64_BIT" |
| 162 | #endif |
| 163 | |
| 164 | |
| 165 | /* Allocation and freeing. */ |
| 166 | |
| 167 | /* BN_new creates a new, allocated BIGNUM and initialises it. */ |
| 168 | OPENSSL_EXPORT BIGNUM *BN_new(void); |
| 169 | |
| 170 | /* BN_init initialises a stack allocated |BIGNUM|. */ |
| 171 | OPENSSL_EXPORT void BN_init(BIGNUM *bn); |
| 172 | |
| 173 | /* BN_free frees the data referenced by |bn| and, if |bn| was originally |
| 174 | * allocated on the heap, frees |bn| also. */ |
| 175 | OPENSSL_EXPORT void BN_free(BIGNUM *bn); |
| 176 | |
| 177 | /* BN_clear_free erases and frees the data referenced by |bn| and, if |bn| was |
| 178 | * originally allocated on the heap, frees |bn| also. */ |
| 179 | OPENSSL_EXPORT void BN_clear_free(BIGNUM *bn); |
| 180 | |
| 181 | /* BN_dup allocates a new BIGNUM and sets it equal to |src|. It returns the |
| 182 | * allocated BIGNUM on success or NULL otherwise. */ |
| 183 | OPENSSL_EXPORT BIGNUM *BN_dup(const BIGNUM *src); |
| 184 | |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 185 | /* BN_copy sets |dest| equal to |src| and returns |dest| or NULL on allocation |
| 186 | * failure. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 187 | OPENSSL_EXPORT BIGNUM *BN_copy(BIGNUM *dest, const BIGNUM *src); |
| 188 | |
| 189 | /* BN_clear sets |bn| to zero and erases the old data. */ |
| 190 | OPENSSL_EXPORT void BN_clear(BIGNUM *bn); |
| 191 | |
| 192 | /* BN_value_one returns a static BIGNUM with value 1. */ |
| 193 | OPENSSL_EXPORT const BIGNUM *BN_value_one(void); |
| 194 | |
| 195 | /* BN_with_flags initialises a stack allocated |BIGNUM| with pointers to the |
| 196 | * contents of |in| but with |flags| ORed into the flags field. |
| 197 | * |
| 198 | * Note: the two BIGNUMs share state and so |out| should /not/ be passed to |
| 199 | * |BN_free|. */ |
| 200 | OPENSSL_EXPORT void BN_with_flags(BIGNUM *out, const BIGNUM *in, int flags); |
| 201 | |
| 202 | |
| 203 | /* Basic functions. */ |
| 204 | |
| 205 | /* BN_num_bits returns the minimum number of bits needed to represent the |
| 206 | * absolute value of |bn|. */ |
| 207 | OPENSSL_EXPORT unsigned BN_num_bits(const BIGNUM *bn); |
| 208 | |
| 209 | /* BN_num_bytes returns the minimum number of bytes needed to represent the |
| 210 | * absolute value of |bn|. */ |
| 211 | OPENSSL_EXPORT unsigned BN_num_bytes(const BIGNUM *bn); |
| 212 | |
| 213 | /* BN_zero sets |bn| to zero. */ |
| 214 | OPENSSL_EXPORT void BN_zero(BIGNUM *bn); |
| 215 | |
| 216 | /* BN_one sets |bn| to one. It returns one on success or zero on allocation |
| 217 | * failure. */ |
| 218 | OPENSSL_EXPORT int BN_one(BIGNUM *bn); |
| 219 | |
| 220 | /* BN_set_word sets |bn| to |value|. It returns one on success or zero on |
| 221 | * allocation failure. */ |
| 222 | OPENSSL_EXPORT int BN_set_word(BIGNUM *bn, BN_ULONG value); |
| 223 | |
| 224 | /* BN_set_negative sets the sign of |bn|. */ |
| 225 | OPENSSL_EXPORT void BN_set_negative(BIGNUM *bn, int sign); |
| 226 | |
| 227 | /* BN_is_negative returns one if |bn| is negative and zero otherwise. */ |
| 228 | OPENSSL_EXPORT int BN_is_negative(const BIGNUM *bn); |
| 229 | |
| 230 | /* BN_get_flags returns |bn->flags| & |flags|. */ |
| 231 | OPENSSL_EXPORT int BN_get_flags(const BIGNUM *bn, int flags); |
| 232 | |
| 233 | /* BN_set_flags sets |flags| on |bn|. */ |
| 234 | OPENSSL_EXPORT void BN_set_flags(BIGNUM *bn, int flags); |
| 235 | |
| 236 | |
| 237 | /* Conversion functions. */ |
| 238 | |
| 239 | /* BN_bin2bn sets |*ret| to the value of |len| bytes from |in|, interpreted as |
| 240 | * a big-endian number, and returns |ret|. If |ret| is NULL then a fresh |
| 241 | * |BIGNUM| is allocated and returned. It returns NULL on allocation |
| 242 | * failure. */ |
| 243 | OPENSSL_EXPORT BIGNUM *BN_bin2bn(const uint8_t *in, size_t len, BIGNUM *ret); |
| 244 | |
| 245 | /* BN_bn2bin serialises the absolute value of |in| to |out| as a big-endian |
| 246 | * integer, which must have |BN_num_bytes| of space available. It returns the |
| 247 | * number of bytes written. */ |
| 248 | OPENSSL_EXPORT size_t BN_bn2bin(const BIGNUM *in, uint8_t *out); |
| 249 | |
| 250 | /* BN_bn2bin_padded serialises the absolute value of |in| to |out| as a |
| 251 | * big-endian integer. The integer is padded with leading zeros up to size |
| 252 | * |len|. If |len| is smaller than |BN_num_bytes|, the function fails and |
| 253 | * returns 0. Otherwise, it returns 1. */ |
| 254 | OPENSSL_EXPORT int BN_bn2bin_padded(uint8_t *out, size_t len, const BIGNUM *in); |
| 255 | |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 256 | /* BN_bn2cbb_padded behaves like |BN_bn2bin_padded| but writes to a |CBB|. */ |
| 257 | OPENSSL_EXPORT int BN_bn2cbb_padded(CBB *out, size_t len, const BIGNUM *in); |
| 258 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 259 | /* BN_bn2hex returns an allocated string that contains a NUL-terminated, hex |
| 260 | * representation of |bn|. If |bn| is negative, the first char in the resulting |
| 261 | * string will be '-'. Returns NULL on allocation failure. */ |
| 262 | OPENSSL_EXPORT char *BN_bn2hex(const BIGNUM *bn); |
| 263 | |
| 264 | /* BN_hex2bn parses the leading hex number from |in|, which may be proceeded by |
| 265 | * a '-' to indicate a negative number and may contain trailing, non-hex data. |
| 266 | * If |outp| is not NULL, it constructs a BIGNUM equal to the hex number and |
| 267 | * stores it in |*outp|. If |*outp| is NULL then it allocates a new BIGNUM and |
| 268 | * updates |*outp|. It returns the number of bytes of |in| processed or zero on |
| 269 | * error. */ |
| 270 | OPENSSL_EXPORT int BN_hex2bn(BIGNUM **outp, const char *in); |
| 271 | |
| 272 | /* BN_bn2dec returns an allocated string that contains a NUL-terminated, |
| 273 | * decimal representation of |bn|. If |bn| is negative, the first char in the |
| 274 | * resulting string will be '-'. Returns NULL on allocation failure. */ |
| 275 | OPENSSL_EXPORT char *BN_bn2dec(const BIGNUM *a); |
| 276 | |
| 277 | /* BN_dec2bn parses the leading decimal number from |in|, which may be |
| 278 | * proceeded by a '-' to indicate a negative number and may contain trailing, |
| 279 | * non-decimal data. If |outp| is not NULL, it constructs a BIGNUM equal to the |
| 280 | * decimal number and stores it in |*outp|. If |*outp| is NULL then it |
| 281 | * allocates a new BIGNUM and updates |*outp|. It returns the number of bytes |
| 282 | * of |in| processed or zero on error. */ |
| 283 | OPENSSL_EXPORT int BN_dec2bn(BIGNUM **outp, const char *in); |
| 284 | |
| 285 | /* BN_asc2bn acts like |BN_dec2bn| or |BN_hex2bn| depending on whether |in| |
| 286 | * begins with "0X" or "0x" (indicating hex) or not (indicating decimal). A |
| 287 | * leading '-' is still permitted and comes before the optional 0X/0x. It |
| 288 | * returns one on success or zero on error. */ |
| 289 | OPENSSL_EXPORT int BN_asc2bn(BIGNUM **outp, const char *in); |
| 290 | |
| 291 | /* BN_print writes a hex encoding of |a| to |bio|. It returns one on success |
| 292 | * and zero on error. */ |
| 293 | OPENSSL_EXPORT int BN_print(BIO *bio, const BIGNUM *a); |
| 294 | |
| 295 | /* BN_print_fp acts like |BIO_print|, but wraps |fp| in a |BIO| first. */ |
| 296 | OPENSSL_EXPORT int BN_print_fp(FILE *fp, const BIGNUM *a); |
| 297 | |
| 298 | /* BN_get_word returns the absolute value of |bn| as a single word. If |bn| is |
| 299 | * too large to be represented as a single word, the maximum possible value |
| 300 | * will be returned. */ |
| 301 | OPENSSL_EXPORT BN_ULONG BN_get_word(const BIGNUM *bn); |
| 302 | |
| 303 | |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 304 | /* ASN.1 functions. */ |
| 305 | |
| 306 | /* BN_cbs2unsigned parses a non-negative DER INTEGER from |cbs| writes the |
| 307 | * result to |ret|. It returns one on success and zero on failure. */ |
| 308 | OPENSSL_EXPORT int BN_cbs2unsigned(CBS *cbs, BIGNUM *ret); |
| 309 | |
| 310 | /* BN_cbs2unsigned_buggy acts like |BN_cbs2unsigned| but tolerates some invalid |
| 311 | * encodings. Do not use this function. */ |
| 312 | OPENSSL_EXPORT int BN_cbs2unsigned_buggy(CBS *cbs, BIGNUM *ret); |
| 313 | |
| 314 | /* BN_bn2cbb marshals |bn| as a non-negative DER INTEGER and appends the result |
| 315 | * to |cbb|. It returns one on success and zero on failure. */ |
| 316 | OPENSSL_EXPORT int BN_bn2cbb(CBB *cbb, const BIGNUM *bn); |
| 317 | |
| 318 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 319 | /* Internal functions. |
| 320 | * |
| 321 | * These functions are useful for code that is doing low-level manipulations of |
| 322 | * BIGNUM values. However, be sure that no other function in this file does |
| 323 | * what you want before turning to these. */ |
| 324 | |
| 325 | /* bn_correct_top decrements |bn->top| until |bn->d[top-1]| is non-zero or |
| 326 | * until |top| is zero. */ |
| 327 | OPENSSL_EXPORT void bn_correct_top(BIGNUM *bn); |
| 328 | |
| 329 | /* bn_wexpand ensures that |bn| has at least |words| works of space without |
| 330 | * altering its value. It returns one on success or zero on allocation |
| 331 | * failure. */ |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 332 | OPENSSL_EXPORT BIGNUM *bn_wexpand(BIGNUM *bn, size_t words); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 333 | |
| 334 | |
| 335 | /* BIGNUM pools. |
| 336 | * |
| 337 | * Certain BIGNUM operations need to use many temporary variables and |
| 338 | * allocating and freeing them can be quite slow. Thus such opertions typically |
| 339 | * take a |BN_CTX| parameter, which contains a pool of |BIGNUMs|. The |ctx| |
| 340 | * argument to a public function may be NULL, in which case a local |BN_CTX| |
| 341 | * will be created just for the lifetime of that call. |
| 342 | * |
| 343 | * A function must call |BN_CTX_start| first. Then, |BN_CTX_get| may be called |
| 344 | * repeatedly to obtain temporary |BIGNUM|s. All |BN_CTX_get| calls must be made |
| 345 | * before calling any other functions that use the |ctx| as an argument. |
| 346 | * |
| 347 | * Finally, |BN_CTX_end| must be called before returning from the function. |
| 348 | * When |BN_CTX_end| is called, the |BIGNUM| pointers obtained from |
| 349 | * |BN_CTX_get| become invalid. */ |
| 350 | |
| 351 | /* BN_CTX_new returns a new, empty BN_CTX or NULL on allocation failure. */ |
| 352 | OPENSSL_EXPORT BN_CTX *BN_CTX_new(void); |
| 353 | |
| 354 | /* BN_CTX_free frees all BIGNUMs contained in |ctx| and then frees |ctx| |
| 355 | * itself. */ |
| 356 | OPENSSL_EXPORT void BN_CTX_free(BN_CTX *ctx); |
| 357 | |
| 358 | /* BN_CTX_start "pushes" a new entry onto the |ctx| stack and allows future |
| 359 | * calls to |BN_CTX_get|. */ |
| 360 | OPENSSL_EXPORT void BN_CTX_start(BN_CTX *ctx); |
| 361 | |
| 362 | /* BN_CTX_get returns a new |BIGNUM|, or NULL on allocation failure. Once |
| 363 | * |BN_CTX_get| has returned NULL, all future calls will also return NULL until |
| 364 | * |BN_CTX_end| is called. */ |
| 365 | OPENSSL_EXPORT BIGNUM *BN_CTX_get(BN_CTX *ctx); |
| 366 | |
| 367 | /* BN_CTX_end invalidates all |BIGNUM|s returned from |BN_CTX_get| since the |
| 368 | * matching |BN_CTX_start| call. */ |
| 369 | OPENSSL_EXPORT void BN_CTX_end(BN_CTX *ctx); |
| 370 | |
| 371 | |
| 372 | /* Simple arithmetic */ |
| 373 | |
| 374 | /* BN_add sets |r| = |a| + |b|, where |r| may be the same pointer as either |a| |
| 375 | * or |b|. It returns one on success and zero on allocation failure. */ |
| 376 | OPENSSL_EXPORT int BN_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); |
| 377 | |
| 378 | /* BN_uadd sets |r| = |a| + |b|, where |a| and |b| are non-negative and |r| may |
| 379 | * be the same pointer as either |a| or |b|. It returns one on success and zero |
| 380 | * on allocation failure. */ |
| 381 | OPENSSL_EXPORT int BN_uadd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); |
| 382 | |
| 383 | /* BN_add_word adds |w| to |a|. It returns one on success and zero otherwise. */ |
| 384 | OPENSSL_EXPORT int BN_add_word(BIGNUM *a, BN_ULONG w); |
| 385 | |
| 386 | /* BN_sub sets |r| = |a| - |b|, where |r| must be a distinct pointer from |a| |
| 387 | * and |b|. It returns one on success and zero on allocation failure. */ |
| 388 | OPENSSL_EXPORT int BN_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); |
| 389 | |
| 390 | /* BN_usub sets |r| = |a| - |b|, where |a| and |b| are non-negative integers, |
| 391 | * |b| < |a| and |r| must be a distinct pointer from |a| and |b|. It returns |
| 392 | * one on success and zero on allocation failure. */ |
| 393 | OPENSSL_EXPORT int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b); |
| 394 | |
| 395 | /* BN_sub_word subtracts |w| from |a|. It returns one on success and zero on |
| 396 | * allocation failure. */ |
| 397 | OPENSSL_EXPORT int BN_sub_word(BIGNUM *a, BN_ULONG w); |
| 398 | |
| 399 | /* BN_mul sets |r| = |a| * |b|, where |r| may be the same pointer as |a| or |
| 400 | * |b|. Returns one on success and zero otherwise. */ |
| 401 | OPENSSL_EXPORT int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 402 | BN_CTX *ctx); |
| 403 | |
| 404 | /* BN_mul_word sets |bn| = |bn| * |w|. It returns one on success or zero on |
| 405 | * allocation failure. */ |
| 406 | OPENSSL_EXPORT int BN_mul_word(BIGNUM *bn, BN_ULONG w); |
| 407 | |
| 408 | /* BN_sqr sets |r| = |a|^2 (i.e. squares), where |r| may be the same pointer as |
| 409 | * |a|. Returns one on success and zero otherwise. This is more efficient than |
| 410 | * BN_mul(r, a, a, ctx). */ |
| 411 | OPENSSL_EXPORT int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx); |
| 412 | |
| 413 | /* BN_div divides |numerator| by |divisor| and places the result in |quotient| |
| 414 | * and the remainder in |rem|. Either of |quotient| or |rem| may be NULL, in |
| 415 | * which case the respective value is not returned. The result is rounded |
| 416 | * towards zero; thus if |numerator| is negative, the remainder will be zero or |
| 417 | * negative. It returns one on success or zero on error. */ |
| 418 | OPENSSL_EXPORT int BN_div(BIGNUM *quotient, BIGNUM *rem, |
| 419 | const BIGNUM *numerator, const BIGNUM *divisor, |
| 420 | BN_CTX *ctx); |
| 421 | |
| 422 | /* BN_div_word sets |numerator| = |numerator|/|divisor| and returns the |
| 423 | * remainder or (BN_ULONG)-1 on error. */ |
| 424 | OPENSSL_EXPORT BN_ULONG BN_div_word(BIGNUM *numerator, BN_ULONG divisor); |
| 425 | |
| 426 | /* BN_sqrt sets |*out_sqrt| (which may be the same |BIGNUM| as |in|) to the |
| 427 | * square root of |in|, using |ctx|. It returns one on success or zero on |
| 428 | * error. Negative numbers and non-square numbers will result in an error with |
| 429 | * appropriate errors on the error queue. */ |
| 430 | OPENSSL_EXPORT int BN_sqrt(BIGNUM *out_sqrt, const BIGNUM *in, BN_CTX *ctx); |
| 431 | |
| 432 | |
| 433 | /* Comparison functions */ |
| 434 | |
| 435 | /* BN_cmp returns a value less than, equal to or greater than zero if |a| is |
| 436 | * less than, equal to or greater than |b|, respectively. */ |
| 437 | OPENSSL_EXPORT int BN_cmp(const BIGNUM *a, const BIGNUM *b); |
| 438 | |
| 439 | /* BN_ucmp returns a value less than, equal to or greater than zero if the |
| 440 | * absolute value of |a| is less than, equal to or greater than the absolute |
| 441 | * value of |b|, respectively. */ |
| 442 | OPENSSL_EXPORT int BN_ucmp(const BIGNUM *a, const BIGNUM *b); |
| 443 | |
| 444 | /* BN_abs_is_word returns one if the absolute value of |bn| equals |w| and zero |
| 445 | * otherwise. */ |
| 446 | OPENSSL_EXPORT int BN_abs_is_word(const BIGNUM *bn, BN_ULONG w); |
| 447 | |
| 448 | /* BN_is_zero returns one if |bn| is zero and zero otherwise. */ |
| 449 | OPENSSL_EXPORT int BN_is_zero(const BIGNUM *bn); |
| 450 | |
| 451 | /* BN_is_one returns one if |bn| equals one and zero otherwise. */ |
| 452 | OPENSSL_EXPORT int BN_is_one(const BIGNUM *bn); |
| 453 | |
| 454 | /* BN_is_word returns one if |bn| is exactly |w| and zero otherwise. */ |
| 455 | OPENSSL_EXPORT int BN_is_word(const BIGNUM *bn, BN_ULONG w); |
| 456 | |
| 457 | /* BN_is_odd returns one if |bn| is odd and zero otherwise. */ |
| 458 | OPENSSL_EXPORT int BN_is_odd(const BIGNUM *bn); |
| 459 | |
| 460 | |
| 461 | /* Bitwise operations. */ |
| 462 | |
| 463 | /* BN_lshift sets |r| equal to |a| << n. The |a| and |r| arguments may be the |
| 464 | * same |BIGNUM|. It returns one on success and zero on allocation failure. */ |
| 465 | OPENSSL_EXPORT int BN_lshift(BIGNUM *r, const BIGNUM *a, int n); |
| 466 | |
| 467 | /* BN_lshift1 sets |r| equal to |a| << 1, where |r| and |a| may be the same |
| 468 | * pointer. It returns one on success and zero on allocation failure. */ |
| 469 | OPENSSL_EXPORT int BN_lshift1(BIGNUM *r, const BIGNUM *a); |
| 470 | |
| 471 | /* BN_rshift sets |r| equal to |a| >> n, where |r| and |a| may be the same |
| 472 | * pointer. It returns one on success and zero on allocation failure. */ |
| 473 | OPENSSL_EXPORT int BN_rshift(BIGNUM *r, const BIGNUM *a, int n); |
| 474 | |
| 475 | /* BN_rshift1 sets |r| equal to |a| >> 1, where |r| and |a| may be the same |
| 476 | * pointer. It returns one on success and zero on allocation failure. */ |
| 477 | OPENSSL_EXPORT int BN_rshift1(BIGNUM *r, const BIGNUM *a); |
| 478 | |
| 479 | /* BN_set_bit sets the |n|th, least-significant bit in |a|. For example, if |a| |
| 480 | * is 2 then setting bit zero will make it 3. It returns one on success or zero |
| 481 | * on allocation failure. */ |
| 482 | OPENSSL_EXPORT int BN_set_bit(BIGNUM *a, int n); |
| 483 | |
| 484 | /* BN_clear_bit clears the |n|th, least-significant bit in |a|. For example, if |
| 485 | * |a| is 3, clearing bit zero will make it two. It returns one on success or |
| 486 | * zero on allocation failure. */ |
| 487 | OPENSSL_EXPORT int BN_clear_bit(BIGNUM *a, int n); |
| 488 | |
| 489 | /* BN_is_bit_set returns the value of the |n|th, least-significant bit in |a|, |
| 490 | * or zero if the bit doesn't exist. */ |
| 491 | OPENSSL_EXPORT int BN_is_bit_set(const BIGNUM *a, int n); |
| 492 | |
| 493 | /* BN_mask_bits truncates |a| so that it is only |n| bits long. It returns one |
| 494 | * on success or zero if |n| is greater than the length of |a| already. */ |
| 495 | OPENSSL_EXPORT int BN_mask_bits(BIGNUM *a, int n); |
| 496 | |
| 497 | |
| 498 | /* Modulo arithmetic. */ |
| 499 | |
| 500 | /* BN_mod_word returns |a| mod |w|. */ |
| 501 | OPENSSL_EXPORT BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w); |
| 502 | |
| 503 | /* BN_mod is a helper macro that calls |BN_div| and discards the quotient. */ |
| 504 | #define BN_mod(rem, numerator, divisor, ctx) \ |
| 505 | BN_div(NULL, (rem), (numerator), (divisor), (ctx)) |
| 506 | |
| 507 | /* BN_nnmod is a non-negative modulo function. It acts like |BN_mod|, but 0 <= |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 508 | * |rem| < |divisor| is always true. It returns one on success and zero on |
| 509 | * error. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 510 | OPENSSL_EXPORT int BN_nnmod(BIGNUM *rem, const BIGNUM *numerator, |
| 511 | const BIGNUM *divisor, BN_CTX *ctx); |
| 512 | |
| 513 | /* BN_mod_add sets |r| = |a| + |b| mod |m|. It returns one on success and zero |
| 514 | * on error. */ |
| 515 | OPENSSL_EXPORT int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 516 | const BIGNUM *m, BN_CTX *ctx); |
| 517 | |
| 518 | /* BN_mod_add_quick acts like |BN_mod_add| but requires that |a| and |b| be |
| 519 | * non-negative and less than |m|. */ |
| 520 | OPENSSL_EXPORT int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 521 | const BIGNUM *m); |
| 522 | |
| 523 | /* BN_mod_sub sets |r| = |a| - |b| mod |m|. It returns one on success and zero |
| 524 | * on error. */ |
| 525 | OPENSSL_EXPORT int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 526 | const BIGNUM *m, BN_CTX *ctx); |
| 527 | |
| 528 | /* BN_mod_sub_quick acts like |BN_mod_sub| but requires that |a| and |b| be |
| 529 | * non-negative and less than |m|. */ |
| 530 | OPENSSL_EXPORT int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 531 | const BIGNUM *m); |
| 532 | |
| 533 | /* BN_mod_mul sets |r| = |a|*|b| mod |m|. It returns one on success and zero |
| 534 | * on error. */ |
| 535 | OPENSSL_EXPORT int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 536 | const BIGNUM *m, BN_CTX *ctx); |
| 537 | |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 538 | /* BN_mod_sqr sets |r| = |a|^2 mod |m|. It returns one on success and zero |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 539 | * on error. */ |
| 540 | OPENSSL_EXPORT int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, |
| 541 | BN_CTX *ctx); |
| 542 | |
| 543 | /* BN_mod_lshift sets |r| = (|a| << n) mod |m|, where |r| and |a| may be the |
| 544 | * same pointer. It returns one on success and zero on error. */ |
| 545 | OPENSSL_EXPORT int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, |
| 546 | const BIGNUM *m, BN_CTX *ctx); |
| 547 | |
| 548 | /* BN_mod_lshift_quick acts like |BN_mod_lshift| but requires that |a| be |
| 549 | * non-negative and less than |m|. */ |
| 550 | OPENSSL_EXPORT int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, |
| 551 | const BIGNUM *m); |
| 552 | |
| 553 | /* BN_mod_lshift1 sets |r| = (|a| << 1) mod |m|, where |r| and |a| may be the |
| 554 | * same pointer. It returns one on success and zero on error. */ |
| 555 | OPENSSL_EXPORT int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, |
| 556 | BN_CTX *ctx); |
| 557 | |
| 558 | /* BN_mod_lshift1_quick acts like |BN_mod_lshift1| but requires that |a| be |
| 559 | * non-negative and less than |m|. */ |
| 560 | OPENSSL_EXPORT int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, |
| 561 | const BIGNUM *m); |
| 562 | |
| 563 | /* BN_mod_sqrt returns a |BIGNUM|, r, such that r^2 == a (mod p). */ |
| 564 | OPENSSL_EXPORT BIGNUM *BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, |
| 565 | BN_CTX *ctx); |
| 566 | |
| 567 | |
| 568 | /* Random and prime number generation. */ |
| 569 | |
Adam Langley | f4e4272 | 2015-06-04 17:45:09 -0700 | [diff] [blame] | 570 | /* BN_rand sets |rnd| to a random number of length |bits|. If |top| is zero, the |
| 571 | * most-significant bit, if any, will be set. If |top| is one, the two most |
| 572 | * significant bits, if any, will be set. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 573 | * |
| 574 | * If |top| is -1 then no extra action will be taken and |BN_num_bits(rnd)| may |
| 575 | * not equal |bits| if the most significant bits randomly ended up as zeros. |
| 576 | * |
Adam Langley | f4e4272 | 2015-06-04 17:45:09 -0700 | [diff] [blame] | 577 | * If |bottom| is non-zero, the least-significant bit, if any, will be set. The |
| 578 | * function returns one on success or zero otherwise. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 579 | OPENSSL_EXPORT int BN_rand(BIGNUM *rnd, int bits, int top, int bottom); |
| 580 | |
| 581 | /* BN_pseudo_rand is an alias for |BN_rand|. */ |
| 582 | OPENSSL_EXPORT int BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom); |
| 583 | |
| 584 | /* BN_rand_range sets |rnd| to a random value [0..range). It returns one on |
| 585 | * success and zero otherwise. */ |
| 586 | OPENSSL_EXPORT int BN_rand_range(BIGNUM *rnd, const BIGNUM *range); |
| 587 | |
| 588 | /* BN_pseudo_rand_range is an alias for BN_rand_range. */ |
| 589 | OPENSSL_EXPORT int BN_pseudo_rand_range(BIGNUM *rnd, const BIGNUM *range); |
| 590 | |
| 591 | /* BN_generate_dsa_nonce generates a random number 0 <= out < range. Unlike |
| 592 | * BN_rand_range, it also includes the contents of |priv| and |message| in the |
| 593 | * generation so that an RNG failure isn't fatal as long as |priv| remains |
| 594 | * secret. This is intended for use in DSA and ECDSA where an RNG weakness |
| 595 | * leads directly to private key exposure unless this function is used. |
| 596 | * It returns one on success and zero on error. */ |
| 597 | OPENSSL_EXPORT int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, |
| 598 | const BIGNUM *priv, |
| 599 | const uint8_t *message, |
| 600 | size_t message_len, BN_CTX *ctx); |
| 601 | |
| 602 | /* BN_GENCB holds a callback function that is used by generation functions that |
| 603 | * can take a very long time to complete. Use |BN_GENCB_set| to initialise a |
| 604 | * |BN_GENCB| structure. |
| 605 | * |
| 606 | * The callback receives the address of that |BN_GENCB| structure as its last |
| 607 | * argument and the user is free to put an arbitary pointer in |arg|. The other |
| 608 | * arguments are set as follows: |
| 609 | * event=BN_GENCB_GENERATED, n=i: after generating the i'th possible prime |
| 610 | * number. |
| 611 | * event=BN_GENCB_PRIME_TEST, n=-1: when finished trial division primality |
| 612 | * checks. |
| 613 | * event=BN_GENCB_PRIME_TEST, n=i: when the i'th primality test has finished. |
| 614 | * |
| 615 | * The callback can return zero to abort the generation progress or one to |
| 616 | * allow it to continue. |
| 617 | * |
| 618 | * When other code needs to call a BN generation function it will often take a |
| 619 | * BN_GENCB argument and may call the function with other argument values. */ |
| 620 | #define BN_GENCB_GENERATED 0 |
| 621 | #define BN_GENCB_PRIME_TEST 1 |
| 622 | |
| 623 | struct bn_gencb_st { |
| 624 | void *arg; /* callback-specific data */ |
| 625 | int (*callback)(int event, int n, struct bn_gencb_st *); |
| 626 | }; |
| 627 | |
| 628 | /* BN_GENCB_set configures |callback| to call |f| and sets |callout->arg| to |
| 629 | * |arg|. */ |
| 630 | OPENSSL_EXPORT void BN_GENCB_set(BN_GENCB *callback, |
| 631 | int (*f)(int event, int n, |
| 632 | struct bn_gencb_st *), |
| 633 | void *arg); |
| 634 | |
| 635 | /* BN_GENCB_call calls |callback|, if not NULL, and returns the return value of |
| 636 | * the callback, or 1 if |callback| is NULL. */ |
| 637 | OPENSSL_EXPORT int BN_GENCB_call(BN_GENCB *callback, int event, int n); |
| 638 | |
| 639 | /* BN_generate_prime_ex sets |ret| to a prime number of |bits| length. If safe |
| 640 | * is non-zero then the prime will be such that (ret-1)/2 is also a prime. |
| 641 | * (This is needed for Diffie-Hellman groups to ensure that the only subgroups |
| 642 | * are of size 2 and (p-1)/2.). |
| 643 | * |
| 644 | * If |add| is not NULL, the prime will fulfill the condition |ret| % |add| == |
| 645 | * |rem| in order to suit a given generator. (If |rem| is NULL then |ret| % |
| 646 | * |add| == 1.) |
| 647 | * |
| 648 | * If |cb| is not NULL, it will be called during processing to give an |
| 649 | * indication of progress. See the comments for |BN_GENCB|. It returns one on |
| 650 | * success and zero otherwise. */ |
| 651 | OPENSSL_EXPORT int BN_generate_prime_ex(BIGNUM *ret, int bits, int safe, |
| 652 | const BIGNUM *add, const BIGNUM *rem, |
| 653 | BN_GENCB *cb); |
| 654 | |
| 655 | /* BN_prime_checks is magic value that can be used as the |checks| argument to |
| 656 | * the primality testing functions in order to automatically select a number of |
| 657 | * Miller-Rabin checks that gives a false positive rate of ~2^{-80}. */ |
| 658 | #define BN_prime_checks 0 |
| 659 | |
| 660 | /* BN_primality_test sets |*is_probably_prime| to one if |candidate| is |
| 661 | * probably a prime number by the Miller-Rabin test or zero if it's certainly |
| 662 | * not. |
| 663 | * |
| 664 | * If |do_trial_division| is non-zero then |candidate| will be tested against a |
| 665 | * list of small primes before Miller-Rabin tests. The probability of this |
| 666 | * function returning a false positive is 2^{2*checks}. If |checks| is |
| 667 | * |BN_prime_checks| then a value that results in approximately 2^{-80} false |
| 668 | * positive probability is used. If |cb| is not NULL then it is called during |
| 669 | * the checking process. See the comment above |BN_GENCB|. |
| 670 | * |
| 671 | * The function returns one on success and zero on error. |
| 672 | * |
| 673 | * (If you are unsure whether you want |do_trial_division|, don't set it.) */ |
| 674 | OPENSSL_EXPORT int BN_primality_test(int *is_probably_prime, |
| 675 | const BIGNUM *candidate, int checks, |
| 676 | BN_CTX *ctx, int do_trial_division, |
| 677 | BN_GENCB *cb); |
| 678 | |
| 679 | /* BN_is_prime_fasttest_ex returns one if |candidate| is probably a prime |
| 680 | * number by the Miller-Rabin test, zero if it's certainly not and -1 on error. |
| 681 | * |
| 682 | * If |do_trial_division| is non-zero then |candidate| will be tested against a |
| 683 | * list of small primes before Miller-Rabin tests. The probability of this |
| 684 | * function returning one when |candidate| is composite is 2^{2*checks}. If |
| 685 | * |checks| is |BN_prime_checks| then a value that results in approximately |
| 686 | * 2^{-80} false positive probability is used. If |cb| is not NULL then it is |
| 687 | * called during the checking process. See the comment above |BN_GENCB|. |
| 688 | * |
| 689 | * WARNING: deprecated. Use |BN_primality_test|. */ |
| 690 | OPENSSL_EXPORT int BN_is_prime_fasttest_ex(const BIGNUM *candidate, int checks, |
| 691 | BN_CTX *ctx, int do_trial_division, |
| 692 | BN_GENCB *cb); |
| 693 | |
| 694 | /* BN_is_prime_ex acts the same as |BN_is_prime_fasttest_ex| with |
| 695 | * |do_trial_division| set to zero. |
| 696 | * |
| 697 | * WARNING: deprecated: Use |BN_primality_test|. */ |
| 698 | OPENSSL_EXPORT int BN_is_prime_ex(const BIGNUM *candidate, int checks, |
| 699 | BN_CTX *ctx, BN_GENCB *cb); |
| 700 | |
| 701 | |
| 702 | /* Number theory functions */ |
| 703 | |
| 704 | /* BN_gcd sets |r| = gcd(|a|, |b|). It returns one on success and zero |
| 705 | * otherwise. */ |
| 706 | OPENSSL_EXPORT int BN_gcd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, |
| 707 | BN_CTX *ctx); |
| 708 | |
| 709 | /* BN_mod_inverse sets |out| equal to |a|^-1, mod |n|. If either of |a| or |n| |
| 710 | * have |BN_FLG_CONSTTIME| set then the operation is performed in constant |
| 711 | * time. If |out| is NULL, a fresh BIGNUM is allocated. It returns the result |
| 712 | * or NULL on error. */ |
| 713 | OPENSSL_EXPORT BIGNUM *BN_mod_inverse(BIGNUM *out, const BIGNUM *a, |
| 714 | const BIGNUM *n, BN_CTX *ctx); |
| 715 | |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 716 | /* BN_mod_inverse_ex acts like |BN_mod_inverse| except that, when it returns |
| 717 | * zero, it will set |*out_no_inverse| to one if the failure was caused because |
| 718 | * |a| has no inverse mod |n|. Otherwise it will set |*out_no_inverse| to |
| 719 | * zero. */ |
| 720 | OPENSSL_EXPORT BIGNUM *BN_mod_inverse_ex(BIGNUM *out, int *out_no_inverse, |
| 721 | const BIGNUM *a, const BIGNUM *n, |
| 722 | BN_CTX *ctx); |
| 723 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 724 | /* BN_kronecker returns the Kronecker symbol of |a| and |b| (which is -1, 0 or |
| 725 | * 1), or -2 on error. */ |
| 726 | OPENSSL_EXPORT int BN_kronecker(const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx); |
| 727 | |
| 728 | |
| 729 | /* Montgomery arithmetic. */ |
| 730 | |
| 731 | /* BN_MONT_CTX contains the precomputed values needed to work in a specific |
| 732 | * Montgomery domain. */ |
| 733 | |
| 734 | /* BN_MONT_CTX_new returns a fresh BN_MONT_CTX or NULL on allocation failure. */ |
| 735 | OPENSSL_EXPORT BN_MONT_CTX *BN_MONT_CTX_new(void); |
| 736 | |
Kenny Root | e99801b | 2015-11-06 15:31:15 -0800 | [diff] [blame] | 737 | /* BN_MONT_CTX_free frees memory associated with |mont|. */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 738 | OPENSSL_EXPORT void BN_MONT_CTX_free(BN_MONT_CTX *mont); |
| 739 | |
| 740 | /* BN_MONT_CTX_copy sets |to| equal to |from|. It returns |to| on success or |
| 741 | * NULL on error. */ |
| 742 | OPENSSL_EXPORT BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 743 | const BN_MONT_CTX *from); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 744 | |
| 745 | /* BN_MONT_CTX_set sets up a Montgomery context given the modulus, |mod|. It |
| 746 | * returns one on success and zero on error. */ |
| 747 | OPENSSL_EXPORT int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, |
| 748 | BN_CTX *ctx); |
| 749 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 750 | /* BN_MONT_CTX_set_locked takes |lock| and checks whether |*pmont| is NULL. If |
| 751 | * so, it creates a new |BN_MONT_CTX| and sets the modulus for it to |mod|. It |
| 752 | * then stores it as |*pmont| and returns it, or NULL on error. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 753 | * |
| 754 | * If |*pmont| is already non-NULL then the existing value is returned. */ |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 755 | BN_MONT_CTX *BN_MONT_CTX_set_locked(BN_MONT_CTX **pmont, CRYPTO_MUTEX *lock, |
| 756 | const BIGNUM *mod, BN_CTX *bn_ctx); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 757 | |
| 758 | /* BN_to_montgomery sets |ret| equal to |a| in the Montgomery domain. It |
| 759 | * returns one on success and zero on error. */ |
| 760 | OPENSSL_EXPORT int BN_to_montgomery(BIGNUM *ret, const BIGNUM *a, |
| 761 | const BN_MONT_CTX *mont, BN_CTX *ctx); |
| 762 | |
| 763 | /* BN_from_montgomery sets |ret| equal to |a| * R^-1, i.e. translates values |
| 764 | * out of the Montgomery domain. It returns one on success or zero on error. */ |
| 765 | OPENSSL_EXPORT int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, |
| 766 | const BN_MONT_CTX *mont, BN_CTX *ctx); |
| 767 | |
| 768 | /* BN_mod_mul_montgomery set |r| equal to |a| * |b|, in the Montgomery domain. |
| 769 | * Both |a| and |b| must already be in the Montgomery domain (by |
| 770 | * |BN_to_montgomery|). It returns one on success or zero on error. */ |
| 771 | OPENSSL_EXPORT int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, |
| 772 | const BIGNUM *b, |
| 773 | const BN_MONT_CTX *mont, BN_CTX *ctx); |
| 774 | |
| 775 | |
| 776 | /* Exponentiation. */ |
| 777 | |
| 778 | /* BN_exp sets |r| equal to |a|^{|p|}. It does so with a square-and-multiply |
| 779 | * algorithm that leaks side-channel information. It returns one on success or |
| 780 | * zero otherwise. */ |
| 781 | OPENSSL_EXPORT int BN_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, |
| 782 | BN_CTX *ctx); |
| 783 | |
| 784 | /* BN_mod_exp sets |r| equal to |a|^{|p|} mod |m|. It does so with the best |
| 785 | * algorithm for the values provided and can run in constant time if |
| 786 | * |BN_FLG_CONSTTIME| is set for |p|. It returns one on success or zero |
| 787 | * otherwise. */ |
| 788 | OPENSSL_EXPORT int BN_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, |
| 789 | const BIGNUM *m, BN_CTX *ctx); |
| 790 | |
| 791 | OPENSSL_EXPORT int BN_mod_exp_mont(BIGNUM *r, const BIGNUM *a, const BIGNUM *p, |
| 792 | const BIGNUM *m, BN_CTX *ctx, |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 793 | const BN_MONT_CTX *mont); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 794 | |
| 795 | OPENSSL_EXPORT int BN_mod_exp_mont_consttime(BIGNUM *rr, const BIGNUM *a, |
| 796 | const BIGNUM *p, const BIGNUM *m, |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 797 | BN_CTX *ctx, |
| 798 | const BN_MONT_CTX *mont); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 799 | |
| 800 | OPENSSL_EXPORT int BN_mod_exp_mont_word(BIGNUM *r, BN_ULONG a, const BIGNUM *p, |
| 801 | const BIGNUM *m, BN_CTX *ctx, |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 802 | const BN_MONT_CTX *mont); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 803 | OPENSSL_EXPORT int BN_mod_exp2_mont(BIGNUM *r, const BIGNUM *a1, |
| 804 | const BIGNUM *p1, const BIGNUM *a2, |
| 805 | const BIGNUM *p2, const BIGNUM *m, |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 806 | BN_CTX *ctx, const BN_MONT_CTX *mont); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 807 | |
| 808 | |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 809 | /* Deprecated functions */ |
| 810 | |
| 811 | /* BN_bn2mpi serialises the value of |in| to |out|, using a format that consists |
| 812 | * of the number's length in bytes represented as a 4-byte big-endian number, |
| 813 | * and the number itself in big-endian format, where the most significant bit |
| 814 | * signals a negative number. (The representation of numbers with the MSB set is |
| 815 | * prefixed with null byte). |out| must have sufficient space available; to |
| 816 | * find the needed amount of space, call the function with |out| set to NULL. */ |
| 817 | OPENSSL_EXPORT size_t BN_bn2mpi(const BIGNUM *in, uint8_t *out); |
| 818 | |
Adam Langley | fad6327 | 2015-11-12 12:15:39 -0800 | [diff] [blame] | 819 | /* BN_mpi2bn parses |len| bytes from |in| and returns the resulting value. The |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 820 | * bytes at |in| are expected to be in the format emitted by |BN_bn2mpi|. |
| 821 | * |
| 822 | * If |out| is NULL then a fresh |BIGNUM| is allocated and returned, otherwise |
| 823 | * |out| is reused and returned. On error, NULL is returned and the error queue |
| 824 | * is updated. */ |
| 825 | OPENSSL_EXPORT BIGNUM *BN_mpi2bn(const uint8_t *in, size_t len, BIGNUM *out); |
| 826 | |
| 827 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 828 | /* Private functions */ |
| 829 | |
| 830 | struct bignum_st { |
| 831 | BN_ULONG *d; /* Pointer to an array of 'BN_BITS2' bit chunks in little-endian |
| 832 | order. */ |
| 833 | int top; /* Index of last used element in |d|, plus one. */ |
| 834 | int dmax; /* Size of |d|, in words. */ |
| 835 | int neg; /* one if the number is negative */ |
| 836 | int flags; /* bitmask of BN_FLG_* values */ |
| 837 | }; |
| 838 | |
| 839 | struct bn_mont_ctx_st { |
| 840 | BIGNUM RR; /* used to convert to montgomery form */ |
| 841 | BIGNUM N; /* The modulus */ |
Adam Langley | 4139edb | 2016-01-13 15:00:54 -0800 | [diff] [blame^] | 842 | BN_ULONG n0[2]; /* least significant words of (R*Ri-1)/N */ |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 843 | }; |
| 844 | |
| 845 | OPENSSL_EXPORT unsigned BN_num_bits_word(BN_ULONG l); |
| 846 | |
| 847 | #define BN_FLG_MALLOCED 0x01 |
| 848 | #define BN_FLG_STATIC_DATA 0x02 |
| 849 | /* avoid leaking exponent information through timing, BN_mod_exp_mont() will |
| 850 | * call BN_mod_exp_mont_consttime, BN_div() will call BN_div_no_branch, |
| 851 | * BN_mod_inverse() will call BN_mod_inverse_no_branch. */ |
| 852 | #define BN_FLG_CONSTTIME 0x04 |
| 853 | |
| 854 | |
| 855 | /* Android compatibility section. |
| 856 | * |
| 857 | * These functions are declared, temporarily, for Android because |
| 858 | * wpa_supplicant will take a little time to sync with upstream. Outside of |
| 859 | * Android they'll have no definition. */ |
| 860 | |
| 861 | OPENSSL_EXPORT BIGNUM *get_rfc3526_prime_1536(BIGNUM *bn); |
| 862 | |
| 863 | |
| 864 | #if defined(__cplusplus) |
| 865 | } /* extern C */ |
| 866 | #endif |
| 867 | |
Adam Langley | e9ada86 | 2015-05-11 17:20:37 -0700 | [diff] [blame] | 868 | #define BN_R_ARG2_LT_ARG3 100 |
| 869 | #define BN_R_BAD_RECIPROCAL 101 |
| 870 | #define BN_R_BIGNUM_TOO_LONG 102 |
| 871 | #define BN_R_BITS_TOO_SMALL 103 |
| 872 | #define BN_R_CALLED_WITH_EVEN_MODULUS 104 |
| 873 | #define BN_R_DIV_BY_ZERO 105 |
| 874 | #define BN_R_EXPAND_ON_STATIC_BIGNUM_DATA 106 |
| 875 | #define BN_R_INPUT_NOT_REDUCED 107 |
| 876 | #define BN_R_INVALID_RANGE 108 |
| 877 | #define BN_R_NEGATIVE_NUMBER 109 |
| 878 | #define BN_R_NOT_A_SQUARE 110 |
| 879 | #define BN_R_NOT_INITIALIZED 111 |
| 880 | #define BN_R_NO_INVERSE 112 |
| 881 | #define BN_R_PRIVATE_KEY_TOO_LARGE 113 |
| 882 | #define BN_R_P_IS_NOT_PRIME 114 |
| 883 | #define BN_R_TOO_MANY_ITERATIONS 115 |
| 884 | #define BN_R_TOO_MANY_TEMPORARY_VARIABLES 116 |
Kenny Root | b849459 | 2015-09-25 02:29:14 +0000 | [diff] [blame] | 885 | #define BN_R_BAD_ENCODING 117 |
| 886 | #define BN_R_ENCODE_ERROR 118 |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 887 | |
| 888 | #endif /* OPENSSL_HEADER_BN_H */ |