tasn_dec.c revision 299068
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 = 0 127 128/* 129 * Decode an ASN1 item, this currently behaves just like a standard 'd2i' 130 * function. 'in' points to a buffer to read the data from, in future we 131 * will have more advanced versions that can input data a piece at a time and 132 * this will simply be a special case. 133 */ 134 135ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, 136 const unsigned char **in, long len, 137 const ASN1_ITEM *it) 138{ 139 ASN1_TLC c; 140 ASN1_VALUE *ptmpval = NULL; 141 if (!pval) 142 pval = &ptmpval; 143 c.valid = 0; 144 if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 145 return *pval; 146 return NULL; 147} 148 149int ASN1_template_d2i(ASN1_VALUE **pval, 150 const unsigned char **in, long len, 151 const ASN1_TEMPLATE *tt) 152{ 153 ASN1_TLC c; 154 c.valid = 0; 155 return asn1_template_ex_d2i(pval, in, len, tt, 0, &c); 156} 157 158/* 159 * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and 160 * tag mismatch return -1 to handle OPTIONAL 161 */ 162 163int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, 164 const ASN1_ITEM *it, 165 int tag, int aclass, char opt, ASN1_TLC *ctx) 166{ 167 const ASN1_TEMPLATE *tt, *errtt = NULL; 168 const ASN1_COMPAT_FUNCS *cf; 169 const ASN1_EXTERN_FUNCS *ef; 170 const ASN1_AUX *aux = it->funcs; 171 ASN1_aux_cb *asn1_cb; 172 const unsigned char *p = NULL, *q; 173 unsigned char *wp = NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */ 174 unsigned char imphack = 0, oclass; 175 char seq_eoc, seq_nolen, cst, isopt; 176 long tmplen; 177 int i; 178 int otag; 179 int ret = 0; 180 ASN1_VALUE **pchptr, *ptmpval; 181 int combine = aclass & ASN1_TFLG_COMBINE; 182 aclass &= ~ASN1_TFLG_COMBINE; 183 if (!pval) 184 return 0; 185 if (aux && aux->asn1_cb) 186 asn1_cb = aux->asn1_cb; 187 else 188 asn1_cb = 0; 189 190 switch (it->itype) { 191 case ASN1_ITYPE_PRIMITIVE: 192 if (it->templates) { 193 /* 194 * tagging or OPTIONAL is currently illegal on an item template 195 * because the flags can't get passed down. In practice this 196 * isn't a problem: we include the relevant flags from the item 197 * template in the template itself. 198 */ 199 if ((tag != -1) || opt) { 200 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 201 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); 202 goto err; 203 } 204 return asn1_template_ex_d2i(pval, in, len, 205 it->templates, opt, ctx); 206 } 207 return asn1_d2i_ex_primitive(pval, in, len, it, 208 tag, aclass, opt, ctx); 209 break; 210 211 case ASN1_ITYPE_MSTRING: 212 p = *in; 213 /* Just read in tag and class */ 214 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, 215 &p, len, -1, 0, 1, ctx); 216 if (!ret) { 217 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 218 goto err; 219 } 220 221 /* Must be UNIVERSAL class */ 222 if (oclass != V_ASN1_UNIVERSAL) { 223 /* If OPTIONAL, assume this is OK */ 224 if (opt) 225 return -1; 226 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL); 227 goto err; 228 } 229 /* Check tag matches bit map */ 230 if (!(ASN1_tag2bit(otag) & it->utype)) { 231 /* If OPTIONAL, assume this is OK */ 232 if (opt) 233 return -1; 234 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG); 235 goto err; 236 } 237 return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx); 238 239 case ASN1_ITYPE_EXTERN: 240 /* Use new style d2i */ 241 ef = it->funcs; 242 return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx); 243 244 case ASN1_ITYPE_COMPAT: 245 /* we must resort to old style evil hackery */ 246 cf = it->funcs; 247 248 /* If OPTIONAL see if it is there */ 249 if (opt) { 250 int exptag; 251 p = *in; 252 if (tag == -1) 253 exptag = it->utype; 254 else 255 exptag = tag; 256 /* 257 * Don't care about anything other than presence of expected tag 258 */ 259 260 ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, 261 &p, len, exptag, aclass, 1, ctx); 262 if (!ret) { 263 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 264 goto err; 265 } 266 if (ret == -1) 267 return -1; 268 } 269 270 /* 271 * This is the old style evil hack IMPLICIT handling: since the 272 * underlying code is expecting a tag and class other than the one 273 * present we change the buffer temporarily then change it back 274 * afterwards. This doesn't and never did work for tags > 30. Yes 275 * this is *horrible* but it is only needed for old style d2i which 276 * will hopefully not be around for much longer. FIXME: should copy 277 * the buffer then modify it so the input buffer can be const: we 278 * should *always* copy because the old style d2i might modify the 279 * buffer. 280 */ 281 282 if (tag != -1) { 283 wp = *(unsigned char **)in; 284 imphack = *wp; 285 if (p == NULL) { 286 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 287 goto err; 288 } 289 *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED) 290 | it->utype); 291 } 292 293 ptmpval = cf->asn1_d2i(pval, in, len); 294 295 if (tag != -1) 296 *wp = imphack; 297 298 if (ptmpval) 299 return 1; 300 301 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 302 goto err; 303 304 case ASN1_ITYPE_CHOICE: 305 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) 306 goto auxerr; 307 if (*pval) { 308 /* Free up and zero CHOICE value if initialised */ 309 i = asn1_get_choice_selector(pval, it); 310 if ((i >= 0) && (i < it->tcount)) { 311 tt = it->templates + i; 312 pchptr = asn1_get_field_ptr(pval, tt); 313 ASN1_template_free(pchptr, tt); 314 asn1_set_choice_selector(pval, -1, it); 315 } 316 } else if (!ASN1_item_ex_new(pval, it)) { 317 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 318 goto err; 319 } 320 /* CHOICE type, try each possibility in turn */ 321 p = *in; 322 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 323 pchptr = asn1_get_field_ptr(pval, tt); 324 /* 325 * We mark field as OPTIONAL so its absence can be recognised. 326 */ 327 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx); 328 /* If field not present, try the next one */ 329 if (ret == -1) 330 continue; 331 /* If positive return, read OK, break loop */ 332 if (ret > 0) 333 break; 334 /* Otherwise must be an ASN1 parsing error */ 335 errtt = tt; 336 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 337 goto err; 338 } 339 340 /* Did we fall off the end without reading anything? */ 341 if (i == it->tcount) { 342 /* If OPTIONAL, this is OK */ 343 if (opt) { 344 /* Free and zero it */ 345 ASN1_item_ex_free(pval, it); 346 return -1; 347 } 348 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE); 349 goto err; 350 } 351 352 asn1_set_choice_selector(pval, i, it); 353 *in = p; 354 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) 355 goto auxerr; 356 return 1; 357 358 case ASN1_ITYPE_NDEF_SEQUENCE: 359 case ASN1_ITYPE_SEQUENCE: 360 p = *in; 361 tmplen = len; 362 363 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */ 364 if (tag == -1) { 365 tag = V_ASN1_SEQUENCE; 366 aclass = V_ASN1_UNIVERSAL; 367 } 368 /* Get SEQUENCE length and update len, p */ 369 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst, 370 &p, len, tag, aclass, opt, ctx); 371 if (!ret) { 372 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 373 goto err; 374 } else if (ret == -1) 375 return -1; 376 if (aux && (aux->flags & ASN1_AFLG_BROKEN)) { 377 len = tmplen - (p - *in); 378 seq_nolen = 1; 379 } 380 /* If indefinite we don't do a length check */ 381 else 382 seq_nolen = seq_eoc; 383 if (!cst) { 384 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED); 385 goto err; 386 } 387 388 if (!*pval && !ASN1_item_ex_new(pval, it)) { 389 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 390 goto err; 391 } 392 393 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) 394 goto auxerr; 395 396 /* Free up and zero any ADB found */ 397 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 398 if (tt->flags & ASN1_TFLG_ADB_MASK) { 399 const ASN1_TEMPLATE *seqtt; 400 ASN1_VALUE **pseqval; 401 seqtt = asn1_do_adb(pval, tt, 1); 402 pseqval = asn1_get_field_ptr(pval, seqtt); 403 ASN1_template_free(pseqval, seqtt); 404 } 405 } 406 407 /* Get each field entry */ 408 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) { 409 const ASN1_TEMPLATE *seqtt; 410 ASN1_VALUE **pseqval; 411 seqtt = asn1_do_adb(pval, tt, 1); 412 if (!seqtt) 413 goto err; 414 pseqval = asn1_get_field_ptr(pval, seqtt); 415 /* Have we ran out of data? */ 416 if (!len) 417 break; 418 q = p; 419 if (asn1_check_eoc(&p, len)) { 420 if (!seq_eoc) { 421 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC); 422 goto err; 423 } 424 len -= p - q; 425 seq_eoc = 0; 426 q = p; 427 break; 428 } 429 /* 430 * This determines the OPTIONAL flag value. The field cannot be 431 * omitted if it is the last of a SEQUENCE and there is still 432 * data to be read. This isn't strictly necessary but it 433 * increases efficiency in some cases. 434 */ 435 if (i == (it->tcount - 1)) 436 isopt = 0; 437 else 438 isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL); 439 /* 440 * attempt to read in field, allowing each to be OPTIONAL 441 */ 442 443 ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx); 444 if (!ret) { 445 errtt = seqtt; 446 goto err; 447 } else if (ret == -1) { 448 /* 449 * OPTIONAL component absent. Free and zero the field. 450 */ 451 ASN1_template_free(pseqval, seqtt); 452 continue; 453 } 454 /* Update length */ 455 len -= p - q; 456 } 457 458 /* Check for EOC if expecting one */ 459 if (seq_eoc && !asn1_check_eoc(&p, len)) { 460 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC); 461 goto err; 462 } 463 /* Check all data read */ 464 if (!seq_nolen && len) { 465 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH); 466 goto err; 467 } 468 469 /* 470 * If we get here we've got no more data in the SEQUENCE, however we 471 * may not have read all fields so check all remaining are OPTIONAL 472 * and clear any that are. 473 */ 474 for (; i < it->tcount; tt++, i++) { 475 const ASN1_TEMPLATE *seqtt; 476 seqtt = asn1_do_adb(pval, tt, 1); 477 if (!seqtt) 478 goto err; 479 if (seqtt->flags & ASN1_TFLG_OPTIONAL) { 480 ASN1_VALUE **pseqval; 481 pseqval = asn1_get_field_ptr(pval, seqtt); 482 ASN1_template_free(pseqval, seqtt); 483 } else { 484 errtt = seqtt; 485 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING); 486 goto err; 487 } 488 } 489 /* Save encoding */ 490 if (!asn1_enc_save(pval, *in, p - *in, it)) 491 goto auxerr; 492 *in = p; 493 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) 494 goto auxerr; 495 return 1; 496 497 default: 498 return 0; 499 } 500 auxerr: 501 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR); 502 err: 503 if (combine == 0) 504 ASN1_item_ex_free(pval, it); 505 if (errtt) 506 ERR_add_error_data(4, "Field=", errtt->field_name, 507 ", Type=", it->sname); 508 else 509 ERR_add_error_data(2, "Type=", it->sname); 510 return 0; 511} 512 513/* 514 * Templates are handled with two separate functions. One handles any 515 * EXPLICIT tag and the other handles the rest. 516 */ 517 518static int asn1_template_ex_d2i(ASN1_VALUE **val, 519 const unsigned char **in, long inlen, 520 const ASN1_TEMPLATE *tt, char opt, 521 ASN1_TLC *ctx) 522{ 523 int flags, aclass; 524 int ret; 525 long len; 526 const unsigned char *p, *q; 527 char exp_eoc; 528 if (!val) 529 return 0; 530 flags = tt->flags; 531 aclass = flags & ASN1_TFLG_TAG_CLASS; 532 533 p = *in; 534 535 /* Check if EXPLICIT tag expected */ 536 if (flags & ASN1_TFLG_EXPTAG) { 537 char cst; 538 /* 539 * Need to work out amount of data available to the inner content and 540 * where it starts: so read in EXPLICIT header to get the info. 541 */ 542 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, 543 &p, inlen, tt->tag, aclass, opt, ctx); 544 q = p; 545 if (!ret) { 546 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 547 return 0; 548 } else if (ret == -1) 549 return -1; 550 if (!cst) { 551 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 552 ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED); 553 return 0; 554 } 555 /* We've found the field so it can't be OPTIONAL now */ 556 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx); 557 if (!ret) { 558 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 559 return 0; 560 } 561 /* We read the field in OK so update length */ 562 len -= p - q; 563 if (exp_eoc) { 564 /* If NDEF we must have an EOC here */ 565 if (!asn1_check_eoc(&p, len)) { 566 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_MISSING_EOC); 567 goto err; 568 } 569 } else { 570 /* 571 * Otherwise we must hit the EXPLICIT tag end or its an error 572 */ 573 if (len) { 574 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 575 ASN1_R_EXPLICIT_LENGTH_MISMATCH); 576 goto err; 577 } 578 } 579 } else 580 return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx); 581 582 *in = p; 583 return 1; 584 585 err: 586 ASN1_template_free(val, tt); 587 return 0; 588} 589 590static int asn1_template_noexp_d2i(ASN1_VALUE **val, 591 const unsigned char **in, long len, 592 const ASN1_TEMPLATE *tt, char opt, 593 ASN1_TLC *ctx) 594{ 595 int flags, aclass; 596 int ret; 597 const unsigned char *p, *q; 598 if (!val) 599 return 0; 600 flags = tt->flags; 601 aclass = flags & ASN1_TFLG_TAG_CLASS; 602 603 p = *in; 604 q = p; 605 606 if (flags & ASN1_TFLG_SK_MASK) { 607 /* SET OF, SEQUENCE OF */ 608 int sktag, skaclass; 609 char sk_eoc; 610 /* First work out expected inner tag value */ 611 if (flags & ASN1_TFLG_IMPTAG) { 612 sktag = tt->tag; 613 skaclass = aclass; 614 } else { 615 skaclass = V_ASN1_UNIVERSAL; 616 if (flags & ASN1_TFLG_SET_OF) 617 sktag = V_ASN1_SET; 618 else 619 sktag = V_ASN1_SEQUENCE; 620 } 621 /* Get the tag */ 622 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, 623 &p, len, sktag, skaclass, opt, ctx); 624 if (!ret) { 625 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 626 return 0; 627 } else if (ret == -1) 628 return -1; 629 if (!*val) 630 *val = (ASN1_VALUE *)sk_new_null(); 631 else { 632 /* 633 * We've got a valid STACK: free up any items present 634 */ 635 STACK *sktmp = (STACK *) * val; 636 ASN1_VALUE *vtmp; 637 while (sk_num(sktmp) > 0) { 638 vtmp = (ASN1_VALUE *)sk_pop(sktmp); 639 ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item)); 640 } 641 } 642 643 if (!*val) { 644 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE); 645 goto err; 646 } 647 648 /* Read as many items as we can */ 649 while (len > 0) { 650 ASN1_VALUE *skfield; 651 q = p; 652 /* See if EOC found */ 653 if (asn1_check_eoc(&p, len)) { 654 if (!sk_eoc) { 655 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 656 ASN1_R_UNEXPECTED_EOC); 657 goto err; 658 } 659 len -= p - q; 660 sk_eoc = 0; 661 break; 662 } 663 skfield = NULL; 664 if (!ASN1_item_ex_d2i(&skfield, &p, len, 665 ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) { 666 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 667 ERR_R_NESTED_ASN1_ERROR); 668 goto err; 669 } 670 len -= p - q; 671 if (!sk_push((STACK *) * val, (char *)skfield)) { 672 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE); 673 goto err; 674 } 675 } 676 if (sk_eoc) { 677 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC); 678 goto err; 679 } 680 } else if (flags & ASN1_TFLG_IMPTAG) { 681 /* IMPLICIT tagging */ 682 ret = ASN1_item_ex_d2i(val, &p, len, 683 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, 684 ctx); 685 if (!ret) { 686 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 687 goto err; 688 } else if (ret == -1) 689 return -1; 690 } else { 691 /* Nothing special */ 692 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), 693 -1, tt->flags & ASN1_TFLG_COMBINE, opt, ctx); 694 if (!ret) { 695 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR); 696 goto err; 697 } else if (ret == -1) 698 return -1; 699 } 700 701 *in = p; 702 return 1; 703 704 err: 705 ASN1_template_free(val, tt); 706 return 0; 707} 708 709static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 710 const unsigned char **in, long inlen, 711 const ASN1_ITEM *it, 712 int tag, int aclass, char opt, ASN1_TLC *ctx) 713{ 714 int ret = 0, utype; 715 long plen; 716 char cst, inf, free_cont = 0; 717 const unsigned char *p; 718 BUF_MEM buf; 719 const unsigned char *cont = NULL; 720 long len; 721 if (!pval) { 722 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL); 723 return 0; /* Should never happen */ 724 } 725 726 if (it->itype == ASN1_ITYPE_MSTRING) { 727 utype = tag; 728 tag = -1; 729 } else 730 utype = it->utype; 731 732 if (utype == V_ASN1_ANY) { 733 /* If type is ANY need to figure out type from tag */ 734 unsigned char oclass; 735 if (tag >= 0) { 736 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY); 737 return 0; 738 } 739 if (opt) { 740 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 741 ASN1_R_ILLEGAL_OPTIONAL_ANY); 742 return 0; 743 } 744 p = *in; 745 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, 746 &p, inlen, -1, 0, 0, ctx); 747 if (!ret) { 748 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); 749 return 0; 750 } 751 if (oclass != V_ASN1_UNIVERSAL) 752 utype = V_ASN1_OTHER; 753 } 754 if (tag == -1) { 755 tag = utype; 756 aclass = V_ASN1_UNIVERSAL; 757 } 758 p = *in; 759 /* Check header */ 760 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, 761 &p, inlen, tag, aclass, opt, ctx); 762 if (!ret) { 763 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); 764 return 0; 765 } else if (ret == -1) 766 return -1; 767 ret = 0; 768 /* SEQUENCE, SET and "OTHER" are left in encoded form */ 769 if ((utype == V_ASN1_SEQUENCE) 770 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) { 771 /* 772 * Clear context cache for type OTHER because the auto clear when we 773 * have a exact match wont work 774 */ 775 if (utype == V_ASN1_OTHER) { 776 asn1_tlc_clear(ctx); 777 } 778 /* SEQUENCE and SET must be constructed */ 779 else if (!cst) { 780 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 781 ASN1_R_TYPE_NOT_CONSTRUCTED); 782 return 0; 783 } 784 785 cont = *in; 786 /* If indefinite length constructed find the real end */ 787 if (inf) { 788 if (!asn1_find_end(&p, plen, inf)) 789 goto err; 790 len = p - cont; 791 } else { 792 len = p - cont + plen; 793 p += plen; 794 buf.data = NULL; 795 } 796 } else if (cst) { 797 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN 798 || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER 799 || utype == V_ASN1_ENUMERATED) { 800 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE); 801 return 0; 802 } 803 buf.length = 0; 804 buf.max = 0; 805 buf.data = NULL; 806 /* 807 * Should really check the internal tags are correct but some things 808 * may get this wrong. The relevant specs say that constructed string 809 * types should be OCTET STRINGs internally irrespective of the type. 810 * So instead just check for UNIVERSAL class and ignore the tag. 811 */ 812 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0)) { 813 free_cont = 1; 814 goto err; 815 } 816 len = buf.length; 817 /* Append a final null to string */ 818 if (!BUF_MEM_grow_clean(&buf, len + 1)) { 819 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE); 820 return 0; 821 } 822 buf.data[len] = 0; 823 cont = (const unsigned char *)buf.data; 824 free_cont = 1; 825 } else { 826 cont = p; 827 len = plen; 828 p += plen; 829 } 830 831 /* We now have content length and type: translate into a structure */ 832 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) 833 goto err; 834 835 *in = p; 836 ret = 1; 837 err: 838 if (free_cont && buf.data) 839 OPENSSL_free(buf.data); 840 return ret; 841} 842 843/* Translate ASN1 content octets into a structure */ 844 845int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 846 int utype, char *free_cont, const ASN1_ITEM *it) 847{ 848 ASN1_VALUE **opval = NULL; 849 ASN1_STRING *stmp; 850 ASN1_TYPE *typ = NULL; 851 int ret = 0; 852 const ASN1_PRIMITIVE_FUNCS *pf; 853 ASN1_INTEGER **tint; 854 pf = it->funcs; 855 856 if (pf && pf->prim_c2i) 857 return pf->prim_c2i(pval, cont, len, utype, free_cont, it); 858 /* If ANY type clear type and set pointer to internal value */ 859 if (it->utype == V_ASN1_ANY) { 860 if (!*pval) { 861 typ = ASN1_TYPE_new(); 862 if (typ == NULL) 863 goto err; 864 *pval = (ASN1_VALUE *)typ; 865 } else 866 typ = (ASN1_TYPE *)*pval; 867 868 if (utype != typ->type) 869 ASN1_TYPE_set(typ, utype, NULL); 870 opval = pval; 871 pval = &typ->value.asn1_value; 872 } 873 switch (utype) { 874 case V_ASN1_OBJECT: 875 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) 876 goto err; 877 break; 878 879 case V_ASN1_NULL: 880 if (len) { 881 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_NULL_IS_WRONG_LENGTH); 882 goto err; 883 } 884 *pval = (ASN1_VALUE *)1; 885 break; 886 887 case V_ASN1_BOOLEAN: 888 if (len != 1) { 889 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BOOLEAN_IS_WRONG_LENGTH); 890 goto err; 891 } else { 892 ASN1_BOOLEAN *tbool; 893 tbool = (ASN1_BOOLEAN *)pval; 894 *tbool = *cont; 895 } 896 break; 897 898 case V_ASN1_BIT_STRING: 899 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) 900 goto err; 901 break; 902 903 case V_ASN1_INTEGER: 904 case V_ASN1_ENUMERATED: 905 tint = (ASN1_INTEGER **)pval; 906 if (!c2i_ASN1_INTEGER(tint, &cont, len)) 907 goto err; 908 /* Fixup type to match the expected form */ 909 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG); 910 break; 911 912 case V_ASN1_OCTET_STRING: 913 case V_ASN1_NUMERICSTRING: 914 case V_ASN1_PRINTABLESTRING: 915 case V_ASN1_T61STRING: 916 case V_ASN1_VIDEOTEXSTRING: 917 case V_ASN1_IA5STRING: 918 case V_ASN1_UTCTIME: 919 case V_ASN1_GENERALIZEDTIME: 920 case V_ASN1_GRAPHICSTRING: 921 case V_ASN1_VISIBLESTRING: 922 case V_ASN1_GENERALSTRING: 923 case V_ASN1_UNIVERSALSTRING: 924 case V_ASN1_BMPSTRING: 925 case V_ASN1_UTF8STRING: 926 case V_ASN1_OTHER: 927 case V_ASN1_SET: 928 case V_ASN1_SEQUENCE: 929 default: 930 if (utype == V_ASN1_BMPSTRING && (len & 1)) { 931 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BMPSTRING_IS_WRONG_LENGTH); 932 goto err; 933 } 934 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) { 935 ASN1err(ASN1_F_ASN1_EX_C2I, 936 ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH); 937 goto err; 938 } 939 /* All based on ASN1_STRING and handled the same */ 940 if (!*pval) { 941 stmp = ASN1_STRING_type_new(utype); 942 if (!stmp) { 943 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE); 944 goto err; 945 } 946 *pval = (ASN1_VALUE *)stmp; 947 } else { 948 stmp = (ASN1_STRING *)*pval; 949 stmp->type = utype; 950 } 951 /* If we've already allocated a buffer use it */ 952 if (*free_cont) { 953 if (stmp->data) 954 OPENSSL_free(stmp->data); 955 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */ 956 stmp->length = len; 957 *free_cont = 0; 958 } else { 959 if (!ASN1_STRING_set(stmp, cont, len)) { 960 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE); 961 ASN1_STRING_free(stmp); 962 *pval = NULL; 963 goto err; 964 } 965 } 966 break; 967 } 968 /* If ASN1_ANY and NULL type fix up value */ 969 if (typ && (utype == V_ASN1_NULL)) 970 typ->value.ptr = NULL; 971 972 ret = 1; 973 err: 974 if (!ret) { 975 ASN1_TYPE_free(typ); 976 if (opval) 977 *opval = NULL; 978 } 979 return ret; 980} 981 982/* 983 * This function finds the end of an ASN1 structure when passed its maximum 984 * length, whether it is indefinite length and a pointer to the content. This 985 * is more efficient than calling asn1_collect because it does not recurse on 986 * each indefinite length header. 987 */ 988 989static int asn1_find_end(const unsigned char **in, long len, char inf) 990{ 991 int expected_eoc; 992 long plen; 993 const unsigned char *p = *in, *q; 994 /* If not indefinite length constructed just add length */ 995 if (inf == 0) { 996 *in += len; 997 return 1; 998 } 999 expected_eoc = 1; 1000 /* 1001 * Indefinite length constructed form. Find the end when enough EOCs are 1002 * found. If more indefinite length constructed headers are encountered 1003 * increment the expected eoc count otherwise just skip to the end of the 1004 * data. 1005 */ 1006 while (len > 0) { 1007 if (asn1_check_eoc(&p, len)) { 1008 expected_eoc--; 1009 if (expected_eoc == 0) 1010 break; 1011 len -= 2; 1012 continue; 1013 } 1014 q = p; 1015 /* Just read in a header: only care about the length */ 1016 if (!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len, 1017 -1, 0, 0, NULL)) { 1018 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR); 1019 return 0; 1020 } 1021 if (inf) 1022 expected_eoc++; 1023 else 1024 p += plen; 1025 len -= p - q; 1026 } 1027 if (expected_eoc) { 1028 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC); 1029 return 0; 1030 } 1031 *in = p; 1032 return 1; 1033} 1034 1035/* 1036 * This function collects the asn1 data from a constructred string type into 1037 * a buffer. The values of 'in' and 'len' should refer to the contents of the 1038 * constructed type and 'inf' should be set if it is indefinite length. 1039 */ 1040 1041#ifndef ASN1_MAX_STRING_NEST 1042/* 1043 * This determines how many levels of recursion are permitted in ASN1 string 1044 * types. If it is not limited stack overflows can occur. If set to zero no 1045 * recursion is allowed at all. Although zero should be adequate examples 1046 * exist that require a value of 1. So 5 should be more than enough. 1047 */ 1048# define ASN1_MAX_STRING_NEST 5 1049#endif 1050 1051static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, 1052 char inf, int tag, int aclass, int depth) 1053{ 1054 const unsigned char *p, *q; 1055 long plen; 1056 char cst, ininf; 1057 p = *in; 1058 inf &= 1; 1059 /* 1060 * If no buffer and not indefinite length constructed just pass over the 1061 * encoded data 1062 */ 1063 if (!buf && !inf) { 1064 *in += len; 1065 return 1; 1066 } 1067 while (len > 0) { 1068 q = p; 1069 /* Check for EOC */ 1070 if (asn1_check_eoc(&p, len)) { 1071 /* 1072 * EOC is illegal outside indefinite length constructed form 1073 */ 1074 if (!inf) { 1075 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC); 1076 return 0; 1077 } 1078 inf = 0; 1079 break; 1080 } 1081 1082 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, 1083 len, tag, aclass, 0, NULL)) { 1084 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR); 1085 return 0; 1086 } 1087 1088 /* If indefinite length constructed update max length */ 1089 if (cst) { 1090 if (depth >= ASN1_MAX_STRING_NEST) { 1091 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING); 1092 return 0; 1093 } 1094 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1)) 1095 return 0; 1096 } else if (plen && !collect_data(buf, &p, plen)) 1097 return 0; 1098 len -= p - q; 1099 } 1100 if (inf) { 1101 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC); 1102 return 0; 1103 } 1104 *in = p; 1105 return 1; 1106} 1107 1108static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen) 1109{ 1110 int len; 1111 if (buf) { 1112 len = buf->length; 1113 if (!BUF_MEM_grow_clean(buf, len + plen)) { 1114 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE); 1115 return 0; 1116 } 1117 memcpy(buf->data + len, *p, plen); 1118 } 1119 *p += plen; 1120 return 1; 1121} 1122 1123/* Check for ASN1 EOC and swallow it if found */ 1124 1125static int asn1_check_eoc(const unsigned char **in, long len) 1126{ 1127 const unsigned char *p; 1128 if (len < 2) 1129 return 0; 1130 p = *in; 1131 if (!p[0] && !p[1]) { 1132 *in += 2; 1133 return 1; 1134 } 1135 return 0; 1136} 1137 1138/* 1139 * Check an ASN1 tag and length: a bit like ASN1_get_object but it sets the 1140 * length for indefinite length constructed form, we don't know the exact 1141 * length but we can set an upper bound to the amount of data available minus 1142 * the header length just read. 1143 */ 1144 1145static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, 1146 char *inf, char *cst, 1147 const unsigned char **in, long len, 1148 int exptag, int expclass, char opt, ASN1_TLC *ctx) 1149{ 1150 int i; 1151 int ptag, pclass; 1152 long plen; 1153 const unsigned char *p, *q; 1154 p = *in; 1155 q = p; 1156 1157 if (ctx && ctx->valid) { 1158 i = ctx->ret; 1159 plen = ctx->plen; 1160 pclass = ctx->pclass; 1161 ptag = ctx->ptag; 1162 p += ctx->hdrlen; 1163 } else { 1164 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len); 1165 if (ctx) { 1166 ctx->ret = i; 1167 ctx->plen = plen; 1168 ctx->pclass = pclass; 1169 ctx->ptag = ptag; 1170 ctx->hdrlen = p - q; 1171 ctx->valid = 1; 1172 /* 1173 * If definite length, and no error, length + header can't exceed 1174 * total amount of data available. 1175 */ 1176 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) { 1177 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG); 1178 asn1_tlc_clear(ctx); 1179 return 0; 1180 } 1181 } 1182 } 1183 1184 if (i & 0x80) { 1185 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER); 1186 asn1_tlc_clear(ctx); 1187 return 0; 1188 } 1189 if (exptag >= 0) { 1190 if ((exptag != ptag) || (expclass != pclass)) { 1191 /* 1192 * If type is OPTIONAL, not an error: indicate missing type. 1193 */ 1194 if (opt) 1195 return -1; 1196 asn1_tlc_clear(ctx); 1197 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG); 1198 return 0; 1199 } 1200 /* 1201 * We have a tag and class match: assume we are going to do something 1202 * with it 1203 */ 1204 asn1_tlc_clear(ctx); 1205 } 1206 1207 if (i & 1) 1208 plen = len - (p - q); 1209 1210 if (inf) 1211 *inf = i & 1; 1212 1213 if (cst) 1214 *cst = i & V_ASN1_CONSTRUCTED; 1215 1216 if (olen) 1217 *olen = plen; 1218 1219 if (oclass) 1220 *oclass = pclass; 1221 1222 if (otag) 1223 *otag = ptag; 1224 1225 *in = p; 1226 return 1; 1227} 1228