bn_print.c revision 325335
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 (BN_is_zero(a)) 76 return OPENSSL_strdup("0"); 77 buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2); 78 if (buf == NULL) { 79 BNerr(BN_F_BN_BN2HEX, ERR_R_MALLOC_FAILURE); 80 goto err; 81 } 82 p = buf; 83 if (a->neg) 84 *(p++) = '-'; 85 for (i = a->top - 1; i >= 0; i--) { 86 for (j = BN_BITS2 - 8; j >= 0; j -= 8) { 87 /* strip leading zeros */ 88 v = ((int)(a->d[i] >> (long)j)) & 0xff; 89 if (z || (v != 0)) { 90 *(p++) = Hex[v >> 4]; 91 *(p++) = Hex[v & 0x0f]; 92 z = 1; 93 } 94 } 95 } 96 *p = '\0'; 97 err: 98 return (buf); 99} 100 101/* Must 'OPENSSL_free' the returned data */ 102char *BN_bn2dec(const BIGNUM *a) 103{ 104 int i = 0, num, ok = 0; 105 char *buf = NULL; 106 char *p; 107 BIGNUM *t = NULL; 108 BN_ULONG *bn_data = NULL, *lp; 109 int bn_data_num; 110 111 /*- 112 * get an upper bound for the length of the decimal integer 113 * num <= (BN_num_bits(a) + 1) * log(2) 114 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error) 115 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1 116 */ 117 i = BN_num_bits(a) * 3; 118 num = (i / 10 + i / 1000 + 1) + 1; 119 bn_data_num = num / BN_DEC_NUM + 1; 120 bn_data = OPENSSL_malloc(bn_data_num * sizeof(BN_ULONG)); 121 buf = OPENSSL_malloc(num + 3); 122 if ((buf == NULL) || (bn_data == NULL)) { 123 BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE); 124 goto err; 125 } 126 if ((t = BN_dup(a)) == NULL) 127 goto err; 128 129#define BUF_REMAIN (num+3 - (size_t)(p - buf)) 130 p = buf; 131 lp = bn_data; 132 if (BN_is_zero(t)) { 133 *(p++) = '0'; 134 *(p++) = '\0'; 135 } else { 136 if (BN_is_negative(t)) 137 *p++ = '-'; 138 139 while (!BN_is_zero(t)) { 140 if (lp - bn_data >= bn_data_num) 141 goto err; 142 *lp = BN_div_word(t, BN_DEC_CONV); 143 if (*lp == (BN_ULONG)-1) 144 goto err; 145 lp++; 146 } 147 lp--; 148 /* 149 * We now have a series of blocks, BN_DEC_NUM chars in length, where 150 * the last one needs truncation. The blocks need to be reversed in 151 * order. 152 */ 153 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp); 154 while (*p) 155 p++; 156 while (lp != bn_data) { 157 lp--; 158 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp); 159 while (*p) 160 p++; 161 } 162 } 163 ok = 1; 164 err: 165 if (bn_data != NULL) 166 OPENSSL_free(bn_data); 167 if (t != NULL) 168 BN_free(t); 169 if (!ok && buf) { 170 OPENSSL_free(buf); 171 buf = NULL; 172 } 173 174 return (buf); 175} 176 177int BN_hex2bn(BIGNUM **bn, const char *a) 178{ 179 BIGNUM *ret = NULL; 180 BN_ULONG l = 0; 181 int neg = 0, h, m, i, j, k, c; 182 int num; 183 184 if ((a == NULL) || (*a == '\0')) 185 return (0); 186 187 if (*a == '-') { 188 neg = 1; 189 a++; 190 } 191 192 for (i = 0; i <= (INT_MAX/4) && isxdigit((unsigned char)a[i]); i++) 193 continue; 194 195 if (i > INT_MAX/4) 196 goto err; 197 198 num = i + neg; 199 if (bn == NULL) 200 return (num); 201 202 /* a is the start of the hex digits, and it is 'i' long */ 203 if (*bn == NULL) { 204 if ((ret = BN_new()) == NULL) 205 return (0); 206 } else { 207 ret = *bn; 208 BN_zero(ret); 209 } 210 211 /* i is the number of hex digits */ 212 if (bn_expand(ret, i * 4) == NULL) 213 goto err; 214 215 j = i; /* least significant 'hex' */ 216 m = 0; 217 h = 0; 218 while (j > 0) { 219 m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j; 220 l = 0; 221 for (;;) { 222 c = a[j - m]; 223 if ((c >= '0') && (c <= '9')) 224 k = c - '0'; 225 else if ((c >= 'a') && (c <= 'f')) 226 k = c - 'a' + 10; 227 else if ((c >= 'A') && (c <= 'F')) 228 k = c - 'A' + 10; 229 else 230 k = 0; /* paranoia */ 231 l = (l << 4) | k; 232 233 if (--m <= 0) { 234 ret->d[h++] = l; 235 break; 236 } 237 } 238 j -= (BN_BYTES * 2); 239 } 240 ret->top = h; 241 bn_correct_top(ret); 242 243 *bn = ret; 244 bn_check_top(ret); 245 /* Don't set the negative flag if it's zero. */ 246 if (ret->top != 0) 247 ret->neg = neg; 248 return (num); 249 err: 250 if (*bn == NULL) 251 BN_free(ret); 252 return (0); 253} 254 255int BN_dec2bn(BIGNUM **bn, const char *a) 256{ 257 BIGNUM *ret = NULL; 258 BN_ULONG l = 0; 259 int neg = 0, i, j; 260 int num; 261 262 if ((a == NULL) || (*a == '\0')) 263 return (0); 264 if (*a == '-') { 265 neg = 1; 266 a++; 267 } 268 269 for (i = 0; i <= (INT_MAX/4) && isdigit((unsigned char)a[i]); i++) 270 continue; 271 272 if (i > INT_MAX/4) 273 goto err; 274 275 num = i + neg; 276 if (bn == NULL) 277 return (num); 278 279 /* 280 * a is the start of the digits, and it is 'i' long. We chop it into 281 * BN_DEC_NUM digits at a time 282 */ 283 if (*bn == NULL) { 284 if ((ret = BN_new()) == NULL) 285 return (0); 286 } else { 287 ret = *bn; 288 BN_zero(ret); 289 } 290 291 /* i is the number of digits, a bit of an over expand */ 292 if (bn_expand(ret, i * 4) == NULL) 293 goto err; 294 295 j = BN_DEC_NUM - (i % BN_DEC_NUM); 296 if (j == BN_DEC_NUM) 297 j = 0; 298 l = 0; 299 while (--i >= 0) { 300 l *= 10; 301 l += *a - '0'; 302 a++; 303 if (++j == BN_DEC_NUM) { 304 BN_mul_word(ret, BN_DEC_CONV); 305 BN_add_word(ret, l); 306 l = 0; 307 j = 0; 308 } 309 } 310 311 bn_correct_top(ret); 312 *bn = ret; 313 bn_check_top(ret); 314 /* Don't set the negative flag if it's zero. */ 315 if (ret->top != 0) 316 ret->neg = neg; 317 return (num); 318 err: 319 if (*bn == NULL) 320 BN_free(ret); 321 return (0); 322} 323 324int BN_asc2bn(BIGNUM **bn, const char *a) 325{ 326 const char *p = a; 327 328 if (*p == '-') 329 p++; 330 331 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x')) { 332 if (!BN_hex2bn(bn, p + 2)) 333 return 0; 334 } else { 335 if (!BN_dec2bn(bn, p)) 336 return 0; 337 } 338 /* Don't set the negative flag if it's zero. */ 339 if (*a == '-' && (*bn)->top != 0) 340 (*bn)->neg = 1; 341 return 1; 342} 343 344#ifndef OPENSSL_NO_BIO 345# ifndef OPENSSL_NO_FP_API 346int BN_print_fp(FILE *fp, const BIGNUM *a) 347{ 348 BIO *b; 349 int ret; 350 351 if ((b = BIO_new(BIO_s_file())) == NULL) 352 return (0); 353 BIO_set_fp(b, fp, BIO_NOCLOSE); 354 ret = BN_print(b, a); 355 BIO_free(b); 356 return (ret); 357} 358# endif 359 360int BN_print(BIO *bp, const BIGNUM *a) 361{ 362 int i, j, v, z = 0; 363 int ret = 0; 364 365 if ((a->neg) && (BIO_write(bp, "-", 1) != 1)) 366 goto end; 367 if (BN_is_zero(a) && (BIO_write(bp, "0", 1) != 1)) 368 goto end; 369 for (i = a->top - 1; i >= 0; i--) { 370 for (j = BN_BITS2 - 4; j >= 0; j -= 4) { 371 /* strip leading zeros */ 372 v = ((int)(a->d[i] >> (long)j)) & 0x0f; 373 if (z || (v != 0)) { 374 if (BIO_write(bp, &(Hex[v]), 1) != 1) 375 goto end; 376 z = 1; 377 } 378 } 379 } 380 ret = 1; 381 end: 382 return (ret); 383} 384#endif 385 386char *BN_options(void) 387{ 388 static int init = 0; 389 static char data[16]; 390 391 if (!init) { 392 init++; 393#ifdef BN_LLONG 394 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 395 (int)sizeof(BN_ULLONG) * 8, (int)sizeof(BN_ULONG) * 8); 396#else 397 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 398 (int)sizeof(BN_ULONG) * 8, (int)sizeof(BN_ULONG) * 8); 399#endif 400 } 401 return (data); 402} 403