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 66 static const char Hex[] = "0123456789ABCDEF"; 67 68 /* Must 'OPENSSL_free' the returned data */ 69 char *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 if (BN_is_zero(a)) 86 *(p++) = '0'; 87 for (i = a->top - 1; i >= 0; i--) { 88 for (j = BN_BITS2 - 8; j >= 0; j -= 8) { 89 /* strip leading zeros */ 90 v = ((int)(a->d[i] >> (long)j)) & 0xff; 91 if (z || (v != 0)) { 92 *(p++) = Hex[v >> 4]; 93 *(p++) = Hex[v & 0x0f]; 94 z = 1; 95 } 96 } 97 } 98 *p = '\0'; 99 err: 100 return (buf); 101 } 102 103 /* Must 'OPENSSL_free' the returned data */ 104 char *BN_bn2dec(const BIGNUM *a) 105 { 106 int i = 0, num, ok = 0; 107 char *buf = NULL; 108 char *p; 109 BIGNUM *t = NULL; 110 BN_ULONG *bn_data = NULL, *lp; 111 int bn_data_num; 112 113 /*- 114 * get an upper bound for the length of the decimal integer 115 * num <= (BN_num_bits(a) + 1) * log(2) 116 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error) 117 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1 118 */ 119 i = BN_num_bits(a) * 3; 120 num = (i / 10 + i / 1000 + 1) + 1; 121 bn_data_num = num / BN_DEC_NUM + 1; 122 bn_data = OPENSSL_malloc(bn_data_num * sizeof(BN_ULONG)); 123 buf = OPENSSL_malloc(num + 3); 124 if ((buf == NULL) || (bn_data == NULL)) { 125 BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE); 126 goto err; 127 } 128 if ((t = BN_dup(a)) == NULL) 129 goto err; 130 131 #define BUF_REMAIN (num+3 - (size_t)(p - buf)) 132 p = buf; 133 lp = bn_data; 134 if (BN_is_zero(t)) { 135 *(p++) = '0'; 136 *(p++) = '\0'; 137 } else { 138 if (BN_is_negative(t)) 139 *p++ = '-'; 140 141 while (!BN_is_zero(t)) { 142 if (lp - bn_data >= bn_data_num) 143 goto err; 144 *lp = BN_div_word(t, BN_DEC_CONV); 145 if (*lp == (BN_ULONG)-1) 146 goto err; 147 lp++; 148 } 149 lp--; 150 /* 151 * We now have a series of blocks, BN_DEC_NUM chars in length, where 152 * the last one needs truncation. The blocks need to be reversed in 153 * order. 154 */ 155 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp); 156 while (*p) 157 p++; 158 while (lp != bn_data) { 159 lp--; 160 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp); 161 while (*p) 162 p++; 163 } 164 } 165 ok = 1; 166 err: 167 if (bn_data != NULL) 168 OPENSSL_free(bn_data); 169 if (t != NULL) 170 BN_free(t); 171 if (!ok && buf) { 172 OPENSSL_free(buf); 173 buf = NULL; 174 } 175 176 return (buf); 177 } 178 179 int BN_hex2bn(BIGNUM **bn, const char *a) 180 { 181 BIGNUM *ret = NULL; 182 BN_ULONG l = 0; 183 int neg = 0, h, m, i, j, k, c; 184 int num; 185 186 if ((a == NULL) || (*a == '\0')) 187 return (0); 188 189 if (*a == '-') { 190 neg = 1; 191 a++; 192 } 193 194 for (i = 0; i <= (INT_MAX/4) && isxdigit((unsigned char)a[i]); i++) 195 continue; 196 197 if (i > INT_MAX/4) 198 goto err; 199 200 num = i + neg; 201 if (bn == NULL) 202 return (num); 203 204 /* a is the start of the hex digits, and it is 'i' long */ 205 if (*bn == NULL) { 206 if ((ret = BN_new()) == NULL) 207 return (0); 208 } else { 209 ret = *bn; 210 BN_zero(ret); 211 } 212 213 /* i is the number of hex digits */ 214 if (bn_expand(ret, i * 4) == NULL) 215 goto err; 216 217 j = i; /* least significant 'hex' */ 218 m = 0; 219 h = 0; 220 while (j > 0) { 221 m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j; 222 l = 0; 223 for (;;) { 224 c = a[j - m]; 225 if ((c >= '0') && (c <= '9')) 226 k = c - '0'; 227 else if ((c >= 'a') && (c <= 'f')) 228 k = c - 'a' + 10; 229 else if ((c >= 'A') && (c <= 'F')) 230 k = c - 'A' + 10; 231 else 232 k = 0; /* paranoia */ 233 l = (l << 4) | k; 234 235 if (--m <= 0) { 236 ret->d[h++] = l; 237 break; 238 } 239 } 240 j -= (BN_BYTES * 2); 241 } 242 ret->top = h; 243 bn_correct_top(ret); 244 245 *bn = ret; 246 bn_check_top(ret); 247 /* Don't set the negative flag if it's zero. */ 248 if (ret->top != 0) 249 ret->neg = neg; 250 return (num); 251 err: 252 if (*bn == NULL) 253 BN_free(ret); 254 return (0); 255 } 256 257 int BN_dec2bn(BIGNUM **bn, const char *a) 258 { 259 BIGNUM *ret = NULL; 260 BN_ULONG l = 0; 261 int neg = 0, i, j; 262 int num; 263 264 if ((a == NULL) || (*a == '\0')) 265 return (0); 266 if (*a == '-') { 267 neg = 1; 268 a++; 269 } 270 271 for (i = 0; i <= (INT_MAX/4) && isdigit((unsigned char)a[i]); i++) 272 continue; 273 274 if (i > INT_MAX/4) 275 goto err; 276 277 num = i + neg; 278 if (bn == NULL) 279 return (num); 280 281 /* 282 * a is the start of the digits, and it is 'i' long. We chop it into 283 * BN_DEC_NUM digits at a time 284 */ 285 if (*bn == NULL) { 286 if ((ret = BN_new()) == NULL) 287 return (0); 288 } else { 289 ret = *bn; 290 BN_zero(ret); 291 } 292 293 /* i is the number of digits, a bit of an over expand */ 294 if (bn_expand(ret, i * 4) == NULL) 295 goto err; 296 297 j = BN_DEC_NUM - (i % BN_DEC_NUM); 298 if (j == BN_DEC_NUM) 299 j = 0; 300 l = 0; 301 while (--i >= 0) { 302 l *= 10; 303 l += *a - '0'; 304 a++; 305 if (++j == BN_DEC_NUM) { 306 BN_mul_word(ret, BN_DEC_CONV); 307 BN_add_word(ret, l); 308 l = 0; 309 j = 0; 310 } 311 } 312 313 bn_correct_top(ret); 314 *bn = ret; 315 bn_check_top(ret); 316 /* Don't set the negative flag if it's zero. */ 317 if (ret->top != 0) 318 ret->neg = neg; 319 return (num); 320 err: 321 if (*bn == NULL) 322 BN_free(ret); 323 return (0); 324 } 325 326 int BN_asc2bn(BIGNUM **bn, const char *a) 327 { 328 const char *p = a; 329 330 if (*p == '-') 331 p++; 332 333 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x')) { 334 if (!BN_hex2bn(bn, p + 2)) 335 return 0; 336 } else { 337 if (!BN_dec2bn(bn, p)) 338 return 0; 339 } 340 /* Don't set the negative flag if it's zero. */ 341 if (*a == '-' && (*bn)->top != 0) 342 (*bn)->neg = 1; 343 return 1; 344 } 345 346 #ifndef OPENSSL_NO_BIO 347 # ifndef OPENSSL_NO_FP_API 348 int BN_print_fp(FILE *fp, const BIGNUM *a) 349 { 350 BIO *b; 351 int ret; 352 353 if ((b = BIO_new(BIO_s_file())) == NULL) 354 return (0); 355 BIO_set_fp(b, fp, BIO_NOCLOSE); 356 ret = BN_print(b, a); 357 BIO_free(b); 358 return (ret); 359 } 360 # endif 361 362 int BN_print(BIO *bp, const BIGNUM *a) 363 { 364 int i, j, v, z = 0; 365 int ret = 0; 366 367 if ((a->neg) && (BIO_write(bp, "-", 1) != 1)) 368 goto end; 369 if (BN_is_zero(a) && (BIO_write(bp, "0", 1) != 1)) 370 goto end; 371 for (i = a->top - 1; i >= 0; i--) { 372 for (j = BN_BITS2 - 4; j >= 0; j -= 4) { 373 /* strip leading zeros */ 374 v = ((int)(a->d[i] >> (long)j)) & 0x0f; 375 if (z || (v != 0)) { 376 if (BIO_write(bp, &(Hex[v]), 1) != 1) 377 goto end; 378 z = 1; 379 } 380 } 381 } 382 ret = 1; 383 end: 384 return (ret); 385 } 386 #endif 387 388 char *BN_options(void) 389 { 390 static int init = 0; 391 static char data[16]; 392 393 if (!init) { 394 init++; 395 #ifdef BN_LLONG 396 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 397 (int)sizeof(BN_ULLONG) * 8, (int)sizeof(BN_ULONG) * 8); 398 #else 399 BIO_snprintf(data, sizeof data, "bn(%d,%d)", 400 (int)sizeof(BN_ULONG) * 8, (int)sizeof(BN_ULONG) * 8); 401 #endif 402 } 403 return (data); 404 } 405