1 /* $OpenBSD: bn_print.c,v 1.23 2014/07/12 16:03:36 miod Exp $ */ 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 <ctype.h> 60 #include <stdio.h> 61 62 #include <openssl/opensslconf.h> 63 64 #include <openssl/bio.h> 65 #include <openssl/buffer.h> 66 #include <openssl/err.h> 67 68 #include "bn_lcl.h" 69 70 static const char Hex[]="0123456789ABCDEF"; 71 72 /* Must 'free' the returned data */ 73 char * 74 BN_bn2hex(const BIGNUM *a) 75 { 76 int i, j, v, z = 0; 77 char *buf; 78 char *p; 79 80 buf = malloc(a->top * BN_BYTES * 2 + 2); 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'; 102 103 err: 104 return (buf); 105 } 106 107 /* Must 'free' the returned data */ 108 char * 109 BN_bn2dec(const BIGNUM *a) 110 { 111 int i = 0, num, ok = 0; 112 char *buf = NULL; 113 char *p; 114 BIGNUM *t = NULL; 115 BN_ULONG *bn_data = NULL, *lp; 116 117 /* get an upper bound for the length of the decimal integer 118 * num <= (BN_num_bits(a) + 1) * log(2) 119 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error) 120 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1 121 */ 122 i = BN_num_bits(a) * 3; 123 num = (i / 10 + i / 1000 + 1) + 1; 124 bn_data = reallocarray(NULL, num / BN_DEC_NUM + 1, sizeof(BN_ULONG)); 125 buf = 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 /* We now have a series of blocks, BN_DEC_NUM chars 150 * in length, where the last one needs truncation. 151 * The blocks need to be reversed in order. */ 152 snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp); 153 while (*p) 154 p++; 155 while (lp != bn_data) { 156 lp--; 157 snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp); 158 while (*p) 159 p++; 160 } 161 } 162 ok = 1; 163 164 err: 165 free(bn_data); 166 BN_free(t); 167 if (!ok && buf) { 168 free(buf); 169 buf = NULL; 170 } 171 172 return (buf); 173 } 174 175 int 176 BN_hex2bn(BIGNUM **bn, const char *a) 177 { 178 BIGNUM *ret = NULL; 179 BN_ULONG l = 0; 180 int neg = 0, h, m, i,j, k, c; 181 int num; 182 183 if ((a == NULL) || (*a == '\0')) 184 return (0); 185 186 if (*a == '-') { 187 neg = 1; 188 a++; 189 } 190 191 for (i = 0; isxdigit((unsigned char)a[i]); i++) 192 ; 193 194 num = i + neg; 195 if (bn == NULL) 196 return (num); 197 198 /* a is the start of the hex digits, and it is 'i' long */ 199 if (*bn == NULL) { 200 if ((ret = BN_new()) == NULL) 201 return (0); 202 } else { 203 ret= *bn; 204 BN_zero(ret); 205 } 206 207 /* i is the number of hex digests; */ 208 if (bn_expand(ret, i * 4) == NULL) 209 goto err; 210 211 j = i; /* least significant 'hex' */ 212 m = 0; 213 h = 0; 214 while (j > 0) { 215 m = ((BN_BYTES*2) <= j) ? (BN_BYTES * 2) : j; 216 l = 0; 217 for (;;) { 218 c = a[j - m]; 219 if ((c >= '0') && (c <= '9')) 220 k = c - '0'; 221 else if ((c >= 'a') && (c <= 'f')) 222 k = c - 'a' + 10; 223 else if ((c >= 'A') && (c <= 'F')) 224 k = c - 'A' + 10; 225 else 226 k = 0; /* paranoia */ 227 l = (l << 4) | k; 228 229 if (--m <= 0) { 230 ret->d[h++] = l; 231 break; 232 } 233 } 234 j -= (BN_BYTES * 2); 235 } 236 ret->top = h; 237 bn_correct_top(ret); 238 ret->neg = neg; 239 240 *bn = ret; 241 bn_check_top(ret); 242 return (num); 243 244 err: 245 if (*bn == NULL) 246 BN_free(ret); 247 return (0); 248 } 249 250 int 251 BN_dec2bn(BIGNUM **bn, const char *a) 252 { 253 BIGNUM *ret = NULL; 254 BN_ULONG l = 0; 255 int neg = 0, i, j; 256 int num; 257 258 if ((a == NULL) || (*a == '\0')) 259 return (0); 260 if (*a == '-') { 261 neg = 1; 262 a++; 263 } 264 265 for (i = 0; isdigit((unsigned char)a[i]); i++) 266 ; 267 268 num = i + neg; 269 if (bn == NULL) 270 return (num); 271 272 /* a is the start of the digits, and it is 'i' long. 273 * We chop it into BN_DEC_NUM digits at a time */ 274 if (*bn == NULL) { 275 if ((ret = BN_new()) == NULL) 276 return (0); 277 } else { 278 ret = *bn; 279 BN_zero(ret); 280 } 281 282 /* i is the number of digests, a bit of an over expand; */ 283 if (bn_expand(ret, i * 4) == NULL) 284 goto err; 285 286 j = BN_DEC_NUM - (i % BN_DEC_NUM); 287 if (j == BN_DEC_NUM) 288 j = 0; 289 l = 0; 290 while (*a) { 291 l *= 10; 292 l += *a - '0'; 293 a++; 294 if (++j == BN_DEC_NUM) { 295 BN_mul_word(ret, BN_DEC_CONV); 296 BN_add_word(ret, l); 297 l = 0; 298 j = 0; 299 } 300 } 301 ret->neg = neg; 302 303 bn_correct_top(ret); 304 *bn = ret; 305 bn_check_top(ret); 306 return (num); 307 308 err: 309 if (*bn == NULL) 310 BN_free(ret); 311 return (0); 312 } 313 314 int 315 BN_asc2bn(BIGNUM **bn, const char *a) 316 { 317 const char *p = a; 318 if (*p == '-') 319 p++; 320 321 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x')) { 322 if (!BN_hex2bn(bn, p + 2)) 323 return 0; 324 } else { 325 if (!BN_dec2bn(bn, p)) 326 return 0; 327 } 328 if (*a == '-') 329 (*bn)->neg = 1; 330 return 1; 331 } 332 333 #ifndef OPENSSL_NO_BIO 334 int 335 BN_print_fp(FILE *fp, const BIGNUM *a) 336 { 337 BIO *b; 338 int ret; 339 340 if ((b = BIO_new(BIO_s_file())) == NULL) 341 return (0); 342 BIO_set_fp(b, fp, BIO_NOCLOSE); 343 ret = BN_print(b, a); 344 BIO_free(b); 345 return (ret); 346 } 347 348 int 349 BN_print(BIO *bp, const BIGNUM *a) 350 { 351 int i, j, v, z = 0; 352 int ret = 0; 353 354 if ((a->neg) && (BIO_write(bp, "-", 1) != 1)) 355 goto end; 356 if (BN_is_zero(a) && (BIO_write(bp, "0", 1) != 1)) 357 goto end; 358 for (i = a->top - 1; i >= 0; i--) { 359 for (j = BN_BITS2 - 4; j >= 0; j -= 4) { 360 /* strip leading zeros */ 361 v = ((int)(a->d[i] >> (long)j)) & 0x0f; 362 if (z || (v != 0)) { 363 if (BIO_write(bp, &(Hex[v]), 1) != 1) 364 goto end; 365 z = 1; 366 } 367 } 368 } 369 ret = 1; 370 371 end: 372 return (ret); 373 } 374 #endif 375 376 char * 377 BN_options(void) 378 { 379 static int init = 0; 380 static char data[16]; 381 382 if (!init) { 383 init++; 384 #ifdef BN_LLONG 385 snprintf(data,sizeof data, "bn(%d,%d)", 386 (int)sizeof(BN_ULLONG) * 8, (int)sizeof(BN_ULONG) * 8); 387 #else 388 snprintf(data,sizeof data, "bn(%d,%d)", 389 (int)sizeof(BN_ULONG) * 8, (int)sizeof(BN_ULONG) * 8); 390 #endif 391 } 392 return (data); 393 } 394