1 /* $OpenBSD: asn1_lib.c,v 1.44.10.1 2020/12/08 15:08:47 tb 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 <limits.h> 60 #include <stdio.h> 61 #include <string.h> 62 63 #include <openssl/asn1.h> 64 #include <openssl/err.h> 65 66 static int asn1_get_length(const unsigned char **pp, int *inf, long *rl, int max); 67 static void asn1_put_length(unsigned char **pp, int length); 68 69 static int 70 _asn1_check_infinite_end(const unsigned char **p, long len) 71 { 72 /* If there is 0 or 1 byte left, the length check should pick 73 * things up */ 74 if (len <= 0) 75 return (1); 76 else if ((len >= 2) && ((*p)[0] == 0) && ((*p)[1] == 0)) { 77 (*p) += 2; 78 return (1); 79 } 80 return (0); 81 } 82 83 int 84 ASN1_check_infinite_end(unsigned char **p, long len) 85 { 86 return _asn1_check_infinite_end((const unsigned char **)p, len); 87 } 88 89 int 90 ASN1_const_check_infinite_end(const unsigned char **p, long len) 91 { 92 return _asn1_check_infinite_end(p, len); 93 } 94 95 int 96 ASN1_get_object(const unsigned char **pp, long *plength, int *ptag, 97 int *pclass, long omax) 98 { 99 int i, ret; 100 long l; 101 const unsigned char *p = *pp; 102 int tag, xclass, inf; 103 long max = omax; 104 105 if (!max) 106 goto err; 107 ret = (*p & V_ASN1_CONSTRUCTED); 108 xclass = (*p & V_ASN1_PRIVATE); 109 i = *p & V_ASN1_PRIMITIVE_TAG; 110 if (i == V_ASN1_PRIMITIVE_TAG) { /* high-tag */ 111 p++; 112 if (--max == 0) 113 goto err; 114 l = 0; 115 while (*p & 0x80) { 116 l <<= 7L; 117 l |= *(p++) & 0x7f; 118 if (--max == 0) 119 goto err; 120 if (l > (INT_MAX >> 7L)) 121 goto err; 122 } 123 l <<= 7L; 124 l |= *(p++) & 0x7f; 125 tag = (int)l; 126 if (--max == 0) 127 goto err; 128 } else { 129 tag = i; 130 p++; 131 if (--max == 0) 132 goto err; 133 } 134 *ptag = tag; 135 *pclass = xclass; 136 if (!asn1_get_length(&p, &inf, plength, (int)max)) 137 goto err; 138 139 if (inf && !(ret & V_ASN1_CONSTRUCTED)) 140 goto err; 141 142 if (*plength > (omax - (p - *pp))) { 143 ASN1error(ASN1_R_TOO_LONG); 144 /* Set this so that even if things are not long enough 145 * the values are set correctly */ 146 ret |= 0x80; 147 } 148 *pp = p; 149 return (ret | inf); 150 151 err: 152 ASN1error(ASN1_R_HEADER_TOO_LONG); 153 return (0x80); 154 } 155 156 static int 157 asn1_get_length(const unsigned char **pp, int *inf, long *rl, int max) 158 { 159 const unsigned char *p = *pp; 160 unsigned long ret = 0; 161 unsigned int i; 162 163 if (max-- < 1) 164 return (0); 165 if (*p == 0x80) { 166 *inf = 1; 167 ret = 0; 168 p++; 169 } else { 170 *inf = 0; 171 i = *p & 0x7f; 172 if (*(p++) & 0x80) { 173 if (max < (int)i) 174 return (0); 175 /* skip leading zeroes */ 176 while (i && *p == 0) { 177 p++; 178 i--; 179 } 180 if (i > sizeof(long)) 181 return 0; 182 while (i-- > 0) { 183 ret <<= 8L; 184 ret |= *(p++); 185 } 186 } else 187 ret = i; 188 } 189 if (ret > LONG_MAX) 190 return 0; 191 *pp = p; 192 *rl = (long)ret; 193 return (1); 194 } 195 196 /* class 0 is constructed 197 * constructed == 2 for indefinite length constructed */ 198 void 199 ASN1_put_object(unsigned char **pp, int constructed, int length, int tag, 200 int xclass) 201 { 202 unsigned char *p = *pp; 203 int i, ttag; 204 205 i = (constructed) ? V_ASN1_CONSTRUCTED : 0; 206 i |= (xclass & V_ASN1_PRIVATE); 207 if (tag < 31) 208 *(p++) = i | (tag & V_ASN1_PRIMITIVE_TAG); 209 else { 210 *(p++) = i | V_ASN1_PRIMITIVE_TAG; 211 for(i = 0, ttag = tag; ttag > 0; i++) 212 ttag >>= 7; 213 ttag = i; 214 while (i-- > 0) { 215 p[i] = tag & 0x7f; 216 if (i != (ttag - 1)) 217 p[i] |= 0x80; 218 tag >>= 7; 219 } 220 p += ttag; 221 } 222 if (constructed == 2) 223 *(p++) = 0x80; 224 else 225 asn1_put_length(&p, length); 226 *pp = p; 227 } 228 229 int 230 ASN1_put_eoc(unsigned char **pp) 231 { 232 unsigned char *p = *pp; 233 234 *p++ = 0; 235 *p++ = 0; 236 *pp = p; 237 return 2; 238 } 239 240 static void 241 asn1_put_length(unsigned char **pp, int length) 242 { 243 unsigned char *p = *pp; 244 245 int i, l; 246 if (length <= 127) 247 *(p++) = (unsigned char)length; 248 else { 249 l = length; 250 for (i = 0; l > 0; i++) 251 l >>= 8; 252 *(p++) = i | 0x80; 253 l = i; 254 while (i-- > 0) { 255 p[i] = length & 0xff; 256 length >>= 8; 257 } 258 p += l; 259 } 260 *pp = p; 261 } 262 263 int 264 ASN1_object_size(int constructed, int length, int tag) 265 { 266 int ret; 267 268 ret = length; 269 ret++; 270 if (tag >= 31) { 271 while (tag > 0) { 272 tag >>= 7; 273 ret++; 274 } 275 } 276 if (constructed == 2) 277 return ret + 3; 278 ret++; 279 if (length > 127) { 280 while (length > 0) { 281 length >>= 8; 282 ret++; 283 } 284 } 285 return (ret); 286 } 287 288 int 289 ASN1_STRING_copy(ASN1_STRING *dst, const ASN1_STRING *str) 290 { 291 if (str == NULL) 292 return 0; 293 dst->type = str->type; 294 if (!ASN1_STRING_set(dst, str->data, str->length)) 295 return 0; 296 dst->flags = str->flags; 297 return 1; 298 } 299 300 ASN1_STRING * 301 ASN1_STRING_dup(const ASN1_STRING *str) 302 { 303 ASN1_STRING *ret; 304 305 if (!str) 306 return NULL; 307 ret = ASN1_STRING_new(); 308 if (!ret) 309 return NULL; 310 if (!ASN1_STRING_copy(ret, str)) { 311 ASN1_STRING_free(ret); 312 return NULL; 313 } 314 return ret; 315 } 316 317 int 318 ASN1_STRING_set(ASN1_STRING *str, const void *_data, int len) 319 { 320 const char *data = _data; 321 322 if (len < 0) { 323 if (data == NULL) 324 return (0); 325 else 326 len = strlen(data); 327 } 328 if ((str->length < len) || (str->data == NULL)) { 329 unsigned char *tmp; 330 tmp = realloc(str->data, len + 1); 331 if (tmp == NULL) { 332 ASN1error(ERR_R_MALLOC_FAILURE); 333 return (0); 334 } 335 str->data = tmp; 336 } 337 str->length = len; 338 if (data != NULL) { 339 memmove(str->data, data, len); 340 } 341 str->data[str->length] = '\0'; 342 return (1); 343 } 344 345 void 346 ASN1_STRING_set0(ASN1_STRING *str, void *data, int len) 347 { 348 freezero(str->data, str->length); 349 str->data = data; 350 str->length = len; 351 } 352 353 ASN1_STRING * 354 ASN1_STRING_new(void) 355 { 356 return (ASN1_STRING_type_new(V_ASN1_OCTET_STRING)); 357 } 358 359 ASN1_STRING * 360 ASN1_STRING_type_new(int type) 361 { 362 ASN1_STRING *ret; 363 364 ret = malloc(sizeof(ASN1_STRING)); 365 if (ret == NULL) { 366 ASN1error(ERR_R_MALLOC_FAILURE); 367 return (NULL); 368 } 369 ret->length = 0; 370 ret->type = type; 371 ret->data = NULL; 372 ret->flags = 0; 373 return (ret); 374 } 375 376 void 377 ASN1_STRING_free(ASN1_STRING *a) 378 { 379 if (a == NULL) 380 return; 381 if (a->data != NULL && !(a->flags & ASN1_STRING_FLAG_NDEF)) 382 freezero(a->data, a->length); 383 free(a); 384 } 385 386 int 387 ASN1_STRING_cmp(const ASN1_STRING *a, const ASN1_STRING *b) 388 { 389 int i; 390 391 if (a == NULL || b == NULL) 392 return -1; 393 i = (a->length - b->length); 394 if (i == 0) { 395 i = memcmp(a->data, b->data, a->length); 396 if (i == 0) 397 return (a->type - b->type); 398 else 399 return (i); 400 } else 401 return (i); 402 } 403 404 void 405 asn1_add_error(const unsigned char *address, int offset) 406 { 407 ERR_asprintf_error_data("offset=%d", offset); 408 } 409 410 int 411 ASN1_STRING_length(const ASN1_STRING *x) 412 { 413 return (x->length); 414 } 415 416 void 417 ASN1_STRING_length_set(ASN1_STRING *x, int len) 418 { 419 x->length = len; 420 } 421 422 int 423 ASN1_STRING_type(const ASN1_STRING *x) 424 { 425 return (x->type); 426 } 427 428 unsigned char * 429 ASN1_STRING_data(ASN1_STRING *x) 430 { 431 return (x->data); 432 } 433 434 const unsigned char * 435 ASN1_STRING_get0_data(const ASN1_STRING *x) 436 { 437 return (x->data); 438 } 439