bn_print.c revision 296341
1/* crypto/bn/bn_print.c */ 2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59#include <stdio.h> 60#include <ctype.h> 61#include <limits.h> 62#include "cryptlib.h" 63#include <openssl/buffer.h> 64#include "bn_lcl.h" 65 66static const char Hex[] = "0123456789ABCDEF"; 67 68/* Must 'OPENSSL_free' the returned data */ 69char *BN_bn2hex(const BIGNUM *a) 70{ 71 int i, j, v, z = 0; 72 char *buf; 73 char *p; 74 75 if (a->neg && BN_is_zero(a)) { 76 /* "-0" == 3 bytes including NULL terminator */ 77 buf = OPENSSL_malloc(3); 78 } else { 79 buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2); 80 } 81 if (buf == NULL) { 82 BNerr(BN_F_BN_BN2HEX, ERR_R_MALLOC_FAILURE); 83 goto err; 84 } 85 p = buf; 86 if (a->neg) 87 *(p++) = '-'; 88 if (BN_is_zero(a)) 89 *(p++) = '0'; 90 for (i = a->top - 1; i >= 0; i--) { 91 for (j = BN_BITS2 - 8; j >= 0; j -= 8) { 92 /* strip leading zeros */ 93 v = ((int)(a->d[i] >> (long)j)) & 0xff; 94 if (z || (v != 0)) { 95 *(p++) = Hex[v >> 4]; 96 *(p++) = Hex[v & 0x0f]; 97 z = 1; 98 } 99 } 100 } 101 *p = '\0'; 102 err: 103 return (buf); 104} 105 106/* Must 'OPENSSL_free' the returned data */ 107char *BN_bn2dec(const BIGNUM *a) 108{ 109 int i = 0, num, ok = 0; 110 char *buf = NULL; 111 char *p; 112 BIGNUM *t = NULL; 113 BN_ULONG *bn_data = NULL, *lp; 114 115 /*- 116 * get an upper bound for the length of the decimal integer 117 * num <= (BN_num_bits(a) + 1) * log(2) 118 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error) 119 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1 120 */ 121 i = BN_num_bits(a) * 3; 122 num = (i / 10 + i / 1000 + 1) + 1; 123 bn_data = 124 (BN_ULONG *)OPENSSL_malloc((num / BN_DEC_NUM + 1) * sizeof(BN_ULONG)); 125 buf = (char *)OPENSSL_malloc(num + 3); 126 if ((buf == NULL) || (bn_data == NULL)) { 127 BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE); 128 goto err; 129 } 130 if ((t = BN_dup(a)) == NULL) 131 goto err; 132 133#define BUF_REMAIN (num+3 - (size_t)(p - buf)) 134 p = buf; 135 lp = bn_data; 136 if (BN_is_zero(t)) { 137 *(p++) = '0'; 138 *(p++) = '\0'; 139 } else { 140 if (BN_is_negative(t)) 141 *p++ = '-'; 142 143 i = 0; 144 while (!BN_is_zero(t)) { 145 *lp = BN_div_word(t, BN_DEC_CONV); 146 lp++; 147 } 148 lp--; 149 /* 150 * We now have a series of blocks, BN_DEC_NUM chars in length, where 151 * the last one needs truncation. The blocks need to be reversed in 152 * order. 153 */ 154 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp); 155 while (*p) 156 p++; 157 while (lp != bn_data) { 158 lp--; 159 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp); 160 while (*p) 161 p++; 162 } 163 } 164 ok = 1; 165 err: 166 if (bn_data != NULL) 167 OPENSSL_free(bn_data); 168 if (t != NULL) 169 BN_free(t); 170 if (!ok && buf) { 171 OPENSSL_free(buf); 172 buf = NULL; 173 } 174 175 return (buf); 176} 177 178int BN_hex2bn(BIGNUM **bn, const char *a) 179{ 180 BIGNUM *ret = NULL; 181 BN_ULONG l = 0; 182 int neg = 0, h, m, i, j, k, c; 183 int num; 184 185 if ((a == NULL) || (*a == '\0')) 186 return (0); 187 188 if (*a == '-') { 189 neg = 1; 190 a++; 191 } 192 193 for (i = 0; i <= (INT_MAX/4) && isxdigit((unsigned char)a[i]); i++) 194 continue; 195 196 if (i > INT_MAX/4) 197 goto err; 198 199 num = i + neg; 200 if (bn == NULL) 201 return (num); 202 203 /* a is the start of the hex digits, and it is 'i' long */ 204 if (*bn == NULL) { 205 if ((ret = BN_new()) == NULL) 206 return (0); 207 } else { 208 ret = *bn; 209 BN_zero(ret); 210 } 211 212 /* i is the number of hex digits */ 213 if (bn_expand(ret, i * 4) == NULL) 214 goto err; 215 216 j = i; /* least significant 'hex' */ 217 m = 0; 218 h = 0; 219 while (j > 0) { 220 m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j; 221 l = 0; 222 for (;;) { 223 c = a[j - m]; 224 if ((c >= '0') && (c <= '9')) 225 k = c - '0'; 226 else if ((c >= 'a') && (c <= 'f')) 227 k = c - 'a' + 10; 228 else if ((c >= 'A') && (c <= 'F')) 229 k = c - 'A' + 10; 230 else 231 k = 0; /* paranoia */ 232 l = (l << 4) | k; 233 234 if (--m <= 0) { 235 ret->d[h++] = l; 236 break; 237 } 238 } 239 j -= (BN_BYTES * 2); 240 } 241 ret->top = h; 242 bn_correct_top(ret); 243 ret->neg = neg; 244 245 *bn = ret; 246 bn_check_top(ret); 247 return (num); 248 err: 249 if (*bn == NULL) 250 BN_free(ret); 251 return (0); 252} 253 254int BN_dec2bn(BIGNUM **bn, const char *a) 255{ 256 BIGNUM *ret = NULL; 257 BN_ULONG l = 0; 258 int neg = 0, i, j; 259 int num; 260 261 if ((a == NULL) || (*a == '\0')) 262 return (0); 263 if (*a == '-') { 264 neg = 1; 265 a++; 266 } 267 268 for (i = 0; i <= (INT_MAX/4) && isdigit((unsigned char)a[i]); i++) 269 continue; 270 271 if (i > INT_MAX/4) 272 goto err; 273 274 num = i + neg; 275 if (bn == NULL) 276 return (num); 277 278 /* 279 * a is the start of the digits, and it is 'i' long. We chop it into 280 * BN_DEC_NUM digits at a time 281 */ 282 if (*bn == NULL) { 283 if ((ret = BN_new()) == NULL) 284 return (0); 285 } else { 286 ret = *bn; 287 BN_zero(ret); 288 } 289 290 /* i is the number of digits, a bit of an over expand */ 291 if (bn_expand(ret, i * 4) == NULL) 292 goto err; 293 294 j = BN_DEC_NUM - (i % BN_DEC_NUM); 295 if (j == BN_DEC_NUM) 296 j = 0; 297 l = 0; 298 while (*a) { 299 l *= 10; 300 l += *a - '0'; 301 a++; 302 if (++j == BN_DEC_NUM) { 303 BN_mul_word(ret, BN_DEC_CONV); 304 BN_add_word(ret, l); 305 l = 0; 306 j = 0; 307 } 308 } 309 ret->neg = neg; 310 311 bn_correct_top(ret); 312 *bn = ret; 313 bn_check_top(ret); 314 return (num); 315 err: 316 if (*bn == NULL) 317 BN_free(ret); 318 return (0); 319} 320 321int BN_asc2bn(BIGNUM **bn, const char *a) 322{ 323 const char *p = a; 324 if (*p == '-') 325 p++; 326 327 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x')) { 328 if (!BN_hex2bn(bn, p + 2)) 329 return 0; 330 } else { 331 if (!BN_dec2bn(bn, p)) 332 return 0; 333 } 334 if (*a == '-') 335 (*bn)->neg = 1; 336 return 1; 337} 338 339#ifndef OPENSSL_NO_BIO 340# ifndef OPENSSL_NO_FP_API 341int BN_print_fp(FILE *fp, const BIGNUM *a) 342{ 343 BIO *b; 344 int ret; 345 346 if ((b = BIO_new(BIO_s_file())) == NULL) 347 return (0); 348 BIO_set_fp(b, fp, BIO_NOCLOSE); 349 ret = BN_print(b, a); 350 BIO_free(b); 351 return (ret); 352} 353# endif 354 355int BN_print(BIO *bp, const BIGNUM *a) 356{ 357 int i, j, v, z = 0; 358 int ret = 0; 359 360 if ((a->neg) && (BIO_write(bp, "-", 1) != 1)) 361 goto end; 362 if (BN_is_zero(a) && (BIO_write(bp, "0", 1) != 1)) 363 goto end; 364 for (i = a->top - 1; i >= 0; i--) { 365 for (j = BN_BITS2 - 4; j >= 0; j -= 4) { 366 /* strip leading zeros */ 367 v = ((int)(a->d[i] >> (long)j)) & 0x0f; 368 if (z || (v != 0)) { 369 if (BIO_write(bp, &(Hex[v]), 1) != 1) 370 goto end; 371 z = 1; 372 } 373 } 374 } 375 ret = 1; 376 end: 377 return (ret); 378} 379#endif 380 381char *BN_options(void) 382{ 383 static int init = 0; 384 static char data[16]; 385 386 if (!init) { 387 init++; 388#ifdef BN_LLONG 389 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 390 (int)sizeof(BN_ULLONG) * 8, (int)sizeof(BN_ULONG) * 8); 391#else 392 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 393 (int)sizeof(BN_ULONG) * 8, (int)sizeof(BN_ULONG) * 8); 394#endif 395 } 396 return (data); 397} 398