tasn_dec.c revision 325335
1/* tasn_dec.c */ 2/* 3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project 4 * 2000. 5 */ 6/* ==================================================================== 7 * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * licensing@OpenSSL.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 * 54 * This product includes cryptographic software written by Eric Young 55 * (eay@cryptsoft.com). This product includes software written by Tim 56 * Hudson (tjh@cryptsoft.com). 57 * 58 */ 59 60#include <stddef.h> 61#include <string.h> 62#include <openssl/asn1.h> 63#include <openssl/asn1t.h> 64#include <openssl/objects.h> 65#include <openssl/buffer.h> 66#include <openssl/err.h> 67 68static int asn1_check_eoc(const unsigned char **in, long len); 69static int asn1_find_end(const unsigned char **in, long len, char inf); 70 71static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, 72 char inf, int tag, int aclass, int depth); 73 74static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen); 75 76static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, 77 char *inf, char *cst, 78 const unsigned char **in, long len, 79 int exptag, int expclass, char opt, ASN1_TLC *ctx); 80 81static int asn1_template_ex_d2i(ASN1_VALUE **pval, 82 const unsigned char **in, long len, 83 const ASN1_TEMPLATE *tt, char opt, 84 ASN1_TLC *ctx); 85static int asn1_template_noexp_d2i(ASN1_VALUE **val, 86 const unsigned char **in, long len, 87 const ASN1_TEMPLATE *tt, char opt, 88 ASN1_TLC *ctx); 89static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 90 const unsigned char **in, long len, 91 const ASN1_ITEM *it, 92 int tag, int aclass, char opt, 93 ASN1_TLC *ctx); 94 95/* Table to convert tags to bit values, used for MSTRING type */ 96static const unsigned long tag2bit[32] = { 97 /* tags 0 - 3 */ 98 0, 0, 0, B_ASN1_BIT_STRING, 99 /* tags 4- 7 */ 100 B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN, 101 /* tags 8-11 */ 102 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, 103 /* tags 12-15 */ 104 B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, 105 /* tags 16-19 */ 106 B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING, 107 /* tags 20-22 */ 108 B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING, 109 /* tags 23-24 */ 110 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, 111 /* tags 25-27 */ 112 B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING, 113 /* tags 28-31 */ 114 B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN, 115}; 116 117unsigned long ASN1_tag2bit(int tag) 118{ 119 if ((tag < 0) || (tag > 30)) 120 return 0; 121 return tag2bit[tag]; 122} 123 124/* Macro to initialize and invalidate the cache */ 125 126#define asn1_tlc_clear(c) if (c) (c)->valid = 0 127/* Version to avoid compiler warning about 'c' always non-NULL */ 128#define asn1_tlc_clear_nc(c) (c)->valid = 0 129 130/* 131 * Decode an ASN1 item, this currently behaves just like a standard 'd2i' 132 * function. 'in' points to a buffer to read the data from, in future we 133 * will have more advanced versions that can input data a piece at a time and 134 * this will simply be a special case. 135 */ 136 137ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, 138 const unsigned char **in, long len, 139 const ASN1_ITEM *it) 140{ 141 ASN1_TLC c; 142 ASN1_VALUE *ptmpval = NULL; 143 if (!pval) 144 pval = &ptmpval; 145 asn1_tlc_clear_nc(&c); 146 if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 147 return *pval; 148 return NULL; 149} 150 151int ASN1_template_d2i(ASN1_VALUE **pval, 152 const unsigned char **in, long len, 153 const ASN1_TEMPLATE *tt) 154{ 155 ASN1_TLC c; 156 asn1_tlc_clear_nc(&c); 157 return asn1_template_ex_d2i(pval, in, len, tt, 0, &c); 158} 159 160/* 161 * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and 162 * tag mismatch return -1 to handle OPTIONAL 163 */ 164 165int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, 166 const ASN1_ITEM *it, 167 int tag, int aclass, char opt, ASN1_TLC *ctx) 168{ 169 const ASN1_TEMPLATE *tt, *errtt = NULL; 170 const ASN1_COMPAT_FUNCS *cf; 171 const ASN1_EXTERN_FUNCS *ef; 172 const ASN1_AUX *aux = it->funcs; 173 ASN1_aux_cb *asn1_cb; 174 const unsigned char *p = NULL, *q; 175 unsigned char *wp = NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */ 176 unsigned char imphack = 0, oclass; 177 char seq_eoc, seq_nolen, cst, isopt; 178 long tmplen; 179 int i; 180 int otag; 181 int ret = 0; 182 ASN1_VALUE **pchptr, *ptmpval; 183 int combine = aclass & ASN1_TFLG_COMBINE; 184 aclass &= ~ASN1_TFLG_COMBINE; 185 if (!pval) 186 return 0; 187 if (aux && aux->asn1_cb) 188 asn1_cb = aux->asn1_cb; 189 else 190 asn1_cb = 0; 191 192 switch (it->itype) { 193 case ASN1_ITYPE_PRIMITIVE: 194 if (it->templates) { 195 /* 196 * tagging or OPTIONAL is currently illegal on an item template 197 * because the flags can't get passed down. In practice this 198 * isn't a problem: we include the relevant flags from the item 199 * template in the template itself. 200 */ 201 if ((tag != -1) || opt) { 202 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 203 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); 204 goto err; 205 } 206 return asn1_template_ex_d2i(pval, in, len, 207 it->templates, opt, ctx); 208 } 209 return asn1_d2i_ex_primitive(pval, in, len, it, 210 tag, aclass, opt, ctx); 211 break; 212 213 case ASN1_ITYPE_MSTRING: 214 p = *in; 215 /* Just read in tag and class */ 216 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, 217 &p, len, -1, 0, 1, ctx); 218 if (!ret) { 219 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 220 goto err; 221 } 222 223 /* Must be UNIVERSAL class */ 224 if (oclass != V_ASN1_UNIVERSAL) { 225 /* If OPTIONAL, assume this is OK */ 226 if (opt) 227 return -1; 228 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL); 229 goto err; 230 } 231 /* Check tag matches bit map */ 232 if (!(ASN1_tag2bit(otag) & it->utype)) { 233 /* If OPTIONAL, assume this is OK */ 234 if (opt) 235 return -1; 236 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG); 237 goto err; 238 } 239 return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx); 240 241 case ASN1_ITYPE_EXTERN: 242 /* Use new style d2i */ 243 ef = it->funcs; 244 return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx); 245 246 case ASN1_ITYPE_COMPAT: 247 /* we must resort to old style evil hackery */ 248 cf = it->funcs; 249 250 /* If OPTIONAL see if it is there */ 251 if (opt) { 252 int exptag; 253 p = *in; 254 if (tag == -1) 255 exptag = it->utype; 256 else 257 exptag = tag; 258 /* 259 * Don't care about anything other than presence of expected tag 260 */ 261 262 ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, 263 &p, len, exptag, aclass, 1, ctx); 264 if (!ret) { 265 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 266 goto err; 267 } 268 if (ret == -1) 269 return -1; 270 } 271 272 /* 273 * This is the old style evil hack IMPLICIT handling: since the 274 * underlying code is expecting a tag and class other than the one 275 * present we change the buffer temporarily then change it back 276 * afterwards. This doesn't and never did work for tags > 30. Yes 277 * this is *horrible* but it is only needed for old style d2i which 278 * will hopefully not be around for much longer. FIXME: should copy 279 * the buffer then modify it so the input buffer can be const: we 280 * should *always* copy because the old style d2i might modify the 281 * buffer. 282 */ 283 284 if (tag != -1) { 285 wp = *(unsigned char **)in; 286 imphack = *wp; 287 if (p == NULL) { 288 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 289 goto err; 290 } 291 *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED) 292 | it->utype); 293 } 294 295 ptmpval = cf->asn1_d2i(pval, in, len); 296 297 if (tag != -1) 298 *wp = imphack; 299 300 if (ptmpval) 301 return 1; 302 303 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 304 goto err; 305 306 case ASN1_ITYPE_CHOICE: 307 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL)) 308 goto auxerr; 309 if (*pval) { 310 /* Free up and zero CHOICE value if initialised */ 311 i = asn1_get_choice_selector(pval, it); 312 if ((i >= 0) && (i < it->tcount)) { 313 tt = it->templates + i; 314 pchptr = asn1_get_field_ptr(pval, tt); 315 ASN1_template_free(pchptr, tt); 316 asn1_set_choice_selector(pval, -1, it); 317 } 318 } else if (!ASN1_item_ex_new(pval, it)) { 319 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 320 goto err; 321 } 322 /* CHOICE type, try each possibility in turn */ 323 p = *in; 324 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 325 pchptr = asn1_get_field_ptr(pval, tt); 326 /* 327 * We mark field as OPTIONAL so its absence can be recognised. 328 */ 329 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx); 330 /* If field not present, try the next one */ 331 if (ret == -1) 332 continue; 333 /* If positive return, read OK, break loop */ 334 if (ret > 0) 335 break; 336 /* Otherwise must be an ASN1 parsing error */ 337 errtt = tt; 338 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 339 goto err; 340 } 341 342 /* Did we fall off the end without reading anything? */ 343 if (i == it->tcount) { 344 /* If OPTIONAL, this is OK */ 345 if (opt) { 346 /* Free and zero it */ 347 ASN1_item_ex_free(pval, it); 348 return -1; 349 } 350 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE); 351 goto err; 352 } 353 354 asn1_set_choice_selector(pval, i, it); 355 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL)) 356 goto auxerr; 357 *in = p; 358 return 1; 359 360 case ASN1_ITYPE_NDEF_SEQUENCE: 361 case ASN1_ITYPE_SEQUENCE: 362 p = *in; 363 tmplen = len; 364 365 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */ 366 if (tag == -1) { 367 tag = V_ASN1_SEQUENCE; 368 aclass = V_ASN1_UNIVERSAL; 369 } 370 /* Get SEQUENCE length and update len, p */ 371 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst, 372 &p, len, tag, aclass, opt, ctx); 373 if (!ret) { 374 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 375 goto err; 376 } else if (ret == -1) 377 return -1; 378 if (aux && (aux->flags & ASN1_AFLG_BROKEN)) { 379 len = tmplen - (p - *in); 380 seq_nolen = 1; 381 } 382 /* If indefinite we don't do a length check */ 383 else 384 seq_nolen = seq_eoc; 385 if (!cst) { 386 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED); 387 goto err; 388 } 389 390 if (!*pval && !ASN1_item_ex_new(pval, it)) { 391 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 392 goto err; 393 } 394 395 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL)) 396 goto auxerr; 397 398 /* Free up and zero any ADB found */ 399 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 400 if (tt->flags & ASN1_TFLG_ADB_MASK) { 401 const ASN1_TEMPLATE *seqtt; 402 ASN1_VALUE **pseqval; 403 seqtt = asn1_do_adb(pval, tt, 0); 404 if (seqtt == NULL) 405 continue; 406 pseqval = asn1_get_field_ptr(pval, seqtt); 407 ASN1_template_free(pseqval, seqtt); 408 } 409 } 410 411 /* Get each field entry */ 412 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 413 const ASN1_TEMPLATE *seqtt; 414 ASN1_VALUE **pseqval; 415 seqtt = asn1_do_adb(pval, tt, 1); 416 if (seqtt == NULL) 417 goto err; 418 pseqval = asn1_get_field_ptr(pval, seqtt); 419 /* Have we ran out of data? */ 420 if (!len) 421 break; 422 q = p; 423 if (asn1_check_eoc(&p, len)) { 424 if (!seq_eoc) { 425 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC); 426 goto err; 427 } 428 len -= p - q; 429 seq_eoc = 0; 430 q = p; 431 break; 432 } 433 /* 434 * This determines the OPTIONAL flag value. The field cannot be 435 * omitted if it is the last of a SEQUENCE and there is still 436 * data to be read. This isn't strictly necessary but it 437 * increases efficiency in some cases. 438 */ 439 if (i == (it->tcount - 1)) 440 isopt = 0; 441 else 442 isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL); 443 /* 444 * attempt to read in field, allowing each to be OPTIONAL 445 */ 446 447 ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx); 448 if (!ret) { 449 errtt = seqtt; 450 goto err; 451 } else if (ret == -1) { 452 /* 453 * OPTIONAL component absent. Free and zero the field. 454 */ 455 ASN1_template_free(pseqval, seqtt); 456 continue; 457 } 458 /* Update length */ 459 len -= p - q; 460 } 461 462 /* Check for EOC if expecting one */ 463 if (seq_eoc && !asn1_check_eoc(&p, len)) { 464 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC); 465 goto err; 466 } 467 /* Check all data read */ 468 if (!seq_nolen && len) { 469 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH); 470 goto err; 471 } 472 473 /* 474 * If we get here we've got no more data in the SEQUENCE, however we 475 * may not have read all fields so check all remaining are OPTIONAL 476 * and clear any that are. 477 */ 478 for (; i < it->tcount; tt++, i++) { 479 const ASN1_TEMPLATE *seqtt; 480 seqtt = asn1_do_adb(pval, tt, 1); 481 if (seqtt == NULL) 482 goto err; 483 if (seqtt->flags & ASN1_TFLG_OPTIONAL) { 484 ASN1_VALUE **pseqval; 485 pseqval = asn1_get_field_ptr(pval, seqtt); 486 ASN1_template_free(pseqval, seqtt); 487 } else { 488 errtt = seqtt; 489 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING); 490 goto err; 491 } 492 } 493 /* Save encoding */ 494 if (!asn1_enc_save(pval, *in, p - *in, it)) 495 goto auxerr; 496 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL)) 497 goto auxerr; 498 *in = p; 499 return 1; 500 501 default: 502 return 0; 503 } 504 auxerr: 505 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR); 506 err: 507 if (combine == 0) 508 ASN1_item_ex_free(pval, it); 509 if (errtt) 510 ERR_add_error_data(4, "Field=", errtt->field_name, 511 ", Type=", it->sname); 512 else 513 ERR_add_error_data(2, "Type=", it->sname); 514 return 0; 515} 516 517/* 518 * Templates are handled with two separate functions. One handles any 519 * EXPLICIT tag and the other handles the rest. 520 */ 521 522static int asn1_template_ex_d2i(ASN1_VALUE **val, 523 const unsigned char **in, long inlen, 524 const ASN1_TEMPLATE *tt, char opt, 525 ASN1_TLC *ctx) 526{ 527 int flags, aclass; 528 int ret; 529 long len; 530 const unsigned char *p, *q; 531 char exp_eoc; 532 if (!val) 533 return 0; 534 flags = tt->flags; 535 aclass = flags & ASN1_TFLG_TAG_CLASS; 536 537 p = *in; 538 539 /* Check if EXPLICIT tag expected */ 540 if (flags & ASN1_TFLG_EXPTAG) { 541 char cst; 542 /* 543 * Need to work out amount of data available to the inner content and 544 * where it starts: so read in EXPLICIT header to get the info. 545 */ 546 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, 547 &p, inlen, tt->tag, aclass, opt, ctx); 548 q = p; 549 if (!ret) { 550 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 551 return 0; 552 } else if (ret == -1) 553 return -1; 554 if (!cst) { 555 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 556 ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED); 557 return 0; 558 } 559 /* We've found the field so it can't be OPTIONAL now */ 560 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx); 561 if (!ret) { 562 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 563 return 0; 564 } 565 /* We read the field in OK so update length */ 566 len -= p - q; 567 if (exp_eoc) { 568 /* If NDEF we must have an EOC here */ 569 if (!asn1_check_eoc(&p, len)) { 570 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_MISSING_EOC); 571 goto err; 572 } 573 } else { 574 /* 575 * Otherwise we must hit the EXPLICIT tag end or its an error 576 */ 577 if (len) { 578 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 579 ASN1_R_EXPLICIT_LENGTH_MISMATCH); 580 goto err; 581 } 582 } 583 } else 584 return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx); 585 586 *in = p; 587 return 1; 588 589 err: 590 ASN1_template_free(val, tt); 591 return 0; 592} 593 594static int asn1_template_noexp_d2i(ASN1_VALUE **val, 595 const unsigned char **in, long len, 596 const ASN1_TEMPLATE *tt, char opt, 597 ASN1_TLC *ctx) 598{ 599 int flags, aclass; 600 int ret; 601 const unsigned char *p, *q; 602 if (!val) 603 return 0; 604 flags = tt->flags; 605 aclass = flags & ASN1_TFLG_TAG_CLASS; 606 607 p = *in; 608 q = p; 609 610 if (flags & ASN1_TFLG_SK_MASK) { 611 /* SET OF, SEQUENCE OF */ 612 int sktag, skaclass; 613 char sk_eoc; 614 /* First work out expected inner tag value */ 615 if (flags & ASN1_TFLG_IMPTAG) { 616 sktag = tt->tag; 617 skaclass = aclass; 618 } else { 619 skaclass = V_ASN1_UNIVERSAL; 620 if (flags & ASN1_TFLG_SET_OF) 621 sktag = V_ASN1_SET; 622 else 623 sktag = V_ASN1_SEQUENCE; 624 } 625 /* Get the tag */ 626 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, 627 &p, len, sktag, skaclass, opt, ctx); 628 if (!ret) { 629 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 630 return 0; 631 } else if (ret == -1) 632 return -1; 633 if (!*val) 634 *val = (ASN1_VALUE *)sk_new_null(); 635 else { 636 /* 637 * We've got a valid STACK: free up any items present 638 */ 639 STACK_OF(ASN1_VALUE) *sktmp = (STACK_OF(ASN1_VALUE) *)*val; 640 ASN1_VALUE *vtmp; 641 while (sk_ASN1_VALUE_num(sktmp) > 0) { 642 vtmp = sk_ASN1_VALUE_pop(sktmp); 643 ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item)); 644 } 645 } 646 647 if (!*val) { 648 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE); 649 goto err; 650 } 651 652 /* Read as many items as we can */ 653 while (len > 0) { 654 ASN1_VALUE *skfield; 655 q = p; 656 /* See if EOC found */ 657 if (asn1_check_eoc(&p, len)) { 658 if (!sk_eoc) { 659 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 660 ASN1_R_UNEXPECTED_EOC); 661 goto err; 662 } 663 len -= p - q; 664 sk_eoc = 0; 665 break; 666 } 667 skfield = NULL; 668 if (!ASN1_item_ex_d2i(&skfield, &p, len, 669 ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) { 670 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 671 ERR_R_NESTED_ASN1_ERROR); 672 goto err; 673 } 674 len -= p - q; 675 if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val, skfield)) { 676 ASN1_item_ex_free(&skfield, ASN1_ITEM_ptr(tt->item)); 677 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE); 678 goto err; 679 } 680 } 681 if (sk_eoc) { 682 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC); 683 goto err; 684 } 685 } else if (flags & ASN1_TFLG_IMPTAG) { 686 /* IMPLICIT tagging */ 687 ret = ASN1_item_ex_d2i(val, &p, len, 688 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, 689 ctx); 690 if (!ret) { 691 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 692 goto err; 693 } else if (ret == -1) 694 return -1; 695 } else { 696 /* Nothing special */ 697 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), 698 -1, tt->flags & ASN1_TFLG_COMBINE, opt, ctx); 699 if (!ret) { 700 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 701 goto err; 702 } else if (ret == -1) 703 return -1; 704 } 705 706 *in = p; 707 return 1; 708 709 err: 710 ASN1_template_free(val, tt); 711 return 0; 712} 713 714static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 715 const unsigned char **in, long inlen, 716 const ASN1_ITEM *it, 717 int tag, int aclass, char opt, ASN1_TLC *ctx) 718{ 719 int ret = 0, utype; 720 long plen; 721 char cst, inf, free_cont = 0; 722 const unsigned char *p; 723 BUF_MEM buf = { 0, NULL, 0 }; 724 const unsigned char *cont = NULL; 725 long len; 726 if (!pval) { 727 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL); 728 return 0; /* Should never happen */ 729 } 730 731 if (it->itype == ASN1_ITYPE_MSTRING) { 732 utype = tag; 733 tag = -1; 734 } else 735 utype = it->utype; 736 737 if (utype == V_ASN1_ANY) { 738 /* If type is ANY need to figure out type from tag */ 739 unsigned char oclass; 740 if (tag >= 0) { 741 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY); 742 return 0; 743 } 744 if (opt) { 745 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 746 ASN1_R_ILLEGAL_OPTIONAL_ANY); 747 return 0; 748 } 749 p = *in; 750 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, 751 &p, inlen, -1, 0, 0, ctx); 752 if (!ret) { 753 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); 754 return 0; 755 } 756 if (oclass != V_ASN1_UNIVERSAL) 757 utype = V_ASN1_OTHER; 758 } 759 if (tag == -1) { 760 tag = utype; 761 aclass = V_ASN1_UNIVERSAL; 762 } 763 p = *in; 764 /* Check header */ 765 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, 766 &p, inlen, tag, aclass, opt, ctx); 767 if (!ret) { 768 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); 769 return 0; 770 } else if (ret == -1) 771 return -1; 772 ret = 0; 773 /* SEQUENCE, SET and "OTHER" are left in encoded form */ 774 if ((utype == V_ASN1_SEQUENCE) 775 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) { 776 /* 777 * Clear context cache for type OTHER because the auto clear when we 778 * have a exact match wont work 779 */ 780 if (utype == V_ASN1_OTHER) { 781 asn1_tlc_clear(ctx); 782 } 783 /* SEQUENCE and SET must be constructed */ 784 else if (!cst) { 785 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 786 ASN1_R_TYPE_NOT_CONSTRUCTED); 787 return 0; 788 } 789 790 cont = *in; 791 /* If indefinite length constructed find the real end */ 792 if (inf) { 793 if (!asn1_find_end(&p, plen, inf)) 794 goto err; 795 len = p - cont; 796 } else { 797 len = p - cont + plen; 798 p += plen; 799 } 800 } else if (cst) { 801 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN 802 || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER 803 || utype == V_ASN1_ENUMERATED) { 804 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE); 805 return 0; 806 } 807 808 /* Free any returned 'buf' content */ 809 free_cont = 1; 810 /* 811 * Should really check the internal tags are correct but some things 812 * may get this wrong. The relevant specs say that constructed string 813 * types should be OCTET STRINGs internally irrespective of the type. 814 * So instead just check for UNIVERSAL class and ignore the tag. 815 */ 816 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0)) { 817 goto err; 818 } 819 len = buf.length; 820 /* Append a final null to string */ 821 if (!BUF_MEM_grow_clean(&buf, len + 1)) { 822 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE); 823 goto err; 824 } 825 buf.data[len] = 0; 826 cont = (const unsigned char *)buf.data; 827 } else { 828 cont = p; 829 len = plen; 830 p += plen; 831 } 832 833 /* We now have content length and type: translate into a structure */ 834 /* asn1_ex_c2i may reuse allocated buffer, and so sets free_cont to 0 */ 835 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) 836 goto err; 837 838 *in = p; 839 ret = 1; 840 err: 841 if (free_cont && buf.data) 842 OPENSSL_free(buf.data); 843 return ret; 844} 845 846/* Translate ASN1 content octets into a structure */ 847 848int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 849 int utype, char *free_cont, const ASN1_ITEM *it) 850{ 851 ASN1_VALUE **opval = NULL; 852 ASN1_STRING *stmp; 853 ASN1_TYPE *typ = NULL; 854 int ret = 0; 855 const ASN1_PRIMITIVE_FUNCS *pf; 856 ASN1_INTEGER **tint; 857 pf = it->funcs; 858 859 if (pf && pf->prim_c2i) 860 return pf->prim_c2i(pval, cont, len, utype, free_cont, it); 861 /* If ANY type clear type and set pointer to internal value */ 862 if (it->utype == V_ASN1_ANY) { 863 if (!*pval) { 864 typ = ASN1_TYPE_new(); 865 if (typ == NULL) 866 goto err; 867 *pval = (ASN1_VALUE *)typ; 868 } else 869 typ = (ASN1_TYPE *)*pval; 870 871 if (utype != typ->type) 872 ASN1_TYPE_set(typ, utype, NULL); 873 opval = pval; 874 pval = &typ->value.asn1_value; 875 } 876 switch (utype) { 877 case V_ASN1_OBJECT: 878 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) 879 goto err; 880 break; 881 882 case V_ASN1_NULL: 883 if (len) { 884 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_NULL_IS_WRONG_LENGTH); 885 goto err; 886 } 887 *pval = (ASN1_VALUE *)1; 888 break; 889 890 case V_ASN1_BOOLEAN: 891 if (len != 1) { 892 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BOOLEAN_IS_WRONG_LENGTH); 893 goto err; 894 } else { 895 ASN1_BOOLEAN *tbool; 896 tbool = (ASN1_BOOLEAN *)pval; 897 *tbool = *cont; 898 } 899 break; 900 901 case V_ASN1_BIT_STRING: 902 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) 903 goto err; 904 break; 905 906 case V_ASN1_INTEGER: 907 case V_ASN1_ENUMERATED: 908 tint = (ASN1_INTEGER **)pval; 909 if (!c2i_ASN1_INTEGER(tint, &cont, len)) 910 goto err; 911 /* Fixup type to match the expected form */ 912 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG); 913 break; 914 915 case V_ASN1_OCTET_STRING: 916 case V_ASN1_NUMERICSTRING: 917 case V_ASN1_PRINTABLESTRING: 918 case V_ASN1_T61STRING: 919 case V_ASN1_VIDEOTEXSTRING: 920 case V_ASN1_IA5STRING: 921 case V_ASN1_UTCTIME: 922 case V_ASN1_GENERALIZEDTIME: 923 case V_ASN1_GRAPHICSTRING: 924 case V_ASN1_VISIBLESTRING: 925 case V_ASN1_GENERALSTRING: 926 case V_ASN1_UNIVERSALSTRING: 927 case V_ASN1_BMPSTRING: 928 case V_ASN1_UTF8STRING: 929 case V_ASN1_OTHER: 930 case V_ASN1_SET: 931 case V_ASN1_SEQUENCE: 932 default: 933 if (utype == V_ASN1_BMPSTRING && (len & 1)) { 934 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BMPSTRING_IS_WRONG_LENGTH); 935 goto err; 936 } 937 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) { 938 ASN1err(ASN1_F_ASN1_EX_C2I, 939 ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH); 940 goto err; 941 } 942 /* All based on ASN1_STRING and handled the same */ 943 if (!*pval) { 944 stmp = ASN1_STRING_type_new(utype); 945 if (!stmp) { 946 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE); 947 goto err; 948 } 949 *pval = (ASN1_VALUE *)stmp; 950 } else { 951 stmp = (ASN1_STRING *)*pval; 952 stmp->type = utype; 953 } 954 /* If we've already allocated a buffer use it */ 955 if (*free_cont) { 956 if (stmp->data) 957 OPENSSL_free(stmp->data); 958 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */ 959 stmp->length = len; 960 *free_cont = 0; 961 } else { 962 if (!ASN1_STRING_set(stmp, cont, len)) { 963 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE); 964 ASN1_STRING_free(stmp); 965 *pval = NULL; 966 goto err; 967 } 968 } 969 break; 970 } 971 /* If ASN1_ANY and NULL type fix up value */ 972 if (typ && (utype == V_ASN1_NULL)) 973 typ->value.ptr = NULL; 974 975 ret = 1; 976 err: 977 if (!ret) { 978 ASN1_TYPE_free(typ); 979 if (opval) 980 *opval = NULL; 981 } 982 return ret; 983} 984 985/* 986 * This function finds the end of an ASN1 structure when passed its maximum 987 * length, whether it is indefinite length and a pointer to the content. This 988 * is more efficient than calling asn1_collect because it does not recurse on 989 * each indefinite length header. 990 */ 991 992static int asn1_find_end(const unsigned char **in, long len, char inf) 993{ 994 int expected_eoc; 995 long plen; 996 const unsigned char *p = *in, *q; 997 /* If not indefinite length constructed just add length */ 998 if (inf == 0) { 999 *in += len; 1000 return 1; 1001 } 1002 expected_eoc = 1; 1003 /* 1004 * Indefinite length constructed form. Find the end when enough EOCs are 1005 * found. If more indefinite length constructed headers are encountered 1006 * increment the expected eoc count otherwise just skip to the end of the 1007 * data. 1008 */ 1009 while (len > 0) { 1010 if (asn1_check_eoc(&p, len)) { 1011 expected_eoc--; 1012 if (expected_eoc == 0) 1013 break; 1014 len -= 2; 1015 continue; 1016 } 1017 q = p; 1018 /* Just read in a header: only care about the length */ 1019 if (!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len, 1020 -1, 0, 0, NULL)) { 1021 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR); 1022 return 0; 1023 } 1024 if (inf) 1025 expected_eoc++; 1026 else 1027 p += plen; 1028 len -= p - q; 1029 } 1030 if (expected_eoc) { 1031 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC); 1032 return 0; 1033 } 1034 *in = p; 1035 return 1; 1036} 1037 1038/* 1039 * This function collects the asn1 data from a constructred string type into 1040 * a buffer. The values of 'in' and 'len' should refer to the contents of the 1041 * constructed type and 'inf' should be set if it is indefinite length. 1042 */ 1043 1044#ifndef ASN1_MAX_STRING_NEST 1045/* 1046 * This determines how many levels of recursion are permitted in ASN1 string 1047 * types. If it is not limited stack overflows can occur. If set to zero no 1048 * recursion is allowed at all. Although zero should be adequate examples 1049 * exist that require a value of 1. So 5 should be more than enough. 1050 */ 1051# define ASN1_MAX_STRING_NEST 5 1052#endif 1053 1054static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, 1055 char inf, int tag, int aclass, int depth) 1056{ 1057 const unsigned char *p, *q; 1058 long plen; 1059 char cst, ininf; 1060 p = *in; 1061 inf &= 1; 1062 /* 1063 * If no buffer and not indefinite length constructed just pass over the 1064 * encoded data 1065 */ 1066 if (!buf && !inf) { 1067 *in += len; 1068 return 1; 1069 } 1070 while (len > 0) { 1071 q = p; 1072 /* Check for EOC */ 1073 if (asn1_check_eoc(&p, len)) { 1074 /* 1075 * EOC is illegal outside indefinite length constructed form 1076 */ 1077 if (!inf) { 1078 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC); 1079 return 0; 1080 } 1081 inf = 0; 1082 break; 1083 } 1084 1085 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, 1086 len, tag, aclass, 0, NULL)) { 1087 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR); 1088 return 0; 1089 } 1090 1091 /* If indefinite length constructed update max length */ 1092 if (cst) { 1093 if (depth >= ASN1_MAX_STRING_NEST) { 1094 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING); 1095 return 0; 1096 } 1097 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1)) 1098 return 0; 1099 } else if (plen && !collect_data(buf, &p, plen)) 1100 return 0; 1101 len -= p - q; 1102 } 1103 if (inf) { 1104 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC); 1105 return 0; 1106 } 1107 *in = p; 1108 return 1; 1109} 1110 1111static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen) 1112{ 1113 int len; 1114 if (buf) { 1115 len = buf->length; 1116 if (!BUF_MEM_grow_clean(buf, len + plen)) { 1117 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE); 1118 return 0; 1119 } 1120 memcpy(buf->data + len, *p, plen); 1121 } 1122 *p += plen; 1123 return 1; 1124} 1125 1126/* Check for ASN1 EOC and swallow it if found */ 1127 1128static int asn1_check_eoc(const unsigned char **in, long len) 1129{ 1130 const unsigned char *p; 1131 if (len < 2) 1132 return 0; 1133 p = *in; 1134 if (!p[0] && !p[1]) { 1135 *in += 2; 1136 return 1; 1137 } 1138 return 0; 1139} 1140 1141/* 1142 * Check an ASN1 tag and length: a bit like ASN1_get_object but it sets the 1143 * length for indefinite length constructed form, we don't know the exact 1144 * length but we can set an upper bound to the amount of data available minus 1145 * the header length just read. 1146 */ 1147 1148static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, 1149 char *inf, char *cst, 1150 const unsigned char **in, long len, 1151 int exptag, int expclass, char opt, ASN1_TLC *ctx) 1152{ 1153 int i; 1154 int ptag, pclass; 1155 long plen; 1156 const unsigned char *p, *q; 1157 p = *in; 1158 q = p; 1159 1160 if (ctx && ctx->valid) { 1161 i = ctx->ret; 1162 plen = ctx->plen; 1163 pclass = ctx->pclass; 1164 ptag = ctx->ptag; 1165 p += ctx->hdrlen; 1166 } else { 1167 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len); 1168 if (ctx) { 1169 ctx->ret = i; 1170 ctx->plen = plen; 1171 ctx->pclass = pclass; 1172 ctx->ptag = ptag; 1173 ctx->hdrlen = p - q; 1174 ctx->valid = 1; 1175 /* 1176 * If definite length, and no error, length + header can't exceed 1177 * total amount of data available. 1178 */ 1179 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) { 1180 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG); 1181 asn1_tlc_clear(ctx); 1182 return 0; 1183 } 1184 } 1185 } 1186 1187 if (i & 0x80) { 1188 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER); 1189 asn1_tlc_clear(ctx); 1190 return 0; 1191 } 1192 if (exptag >= 0) { 1193 if ((exptag != ptag) || (expclass != pclass)) { 1194 /* 1195 * If type is OPTIONAL, not an error: indicate missing type. 1196 */ 1197 if (opt) 1198 return -1; 1199 asn1_tlc_clear(ctx); 1200 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG); 1201 return 0; 1202 } 1203 /* 1204 * We have a tag and class match: assume we are going to do something 1205 * with it 1206 */ 1207 asn1_tlc_clear(ctx); 1208 } 1209 1210 if (i & 1) 1211 plen = len - (p - q); 1212 1213 if (inf) 1214 *inf = i & 1; 1215 1216 if (cst) 1217 *cst = i & V_ASN1_CONSTRUCTED; 1218 1219 if (olen) 1220 *olen = plen; 1221 1222 if (oclass) 1223 *oclass = pclass; 1224 1225 if (otag) 1226 *otag = ptag; 1227 1228 *in = p; 1229 return 1; 1230} 1231