1 /* tasn_dec.c */ 2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL 3 * project 2000. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing@OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 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 68 static int asn1_check_eoc(const unsigned char **in, long len); 69 static int asn1_find_end(const unsigned char **in, long len, char inf); 70 71 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, 72 char inf, int tag, int aclass); 73 74 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen); 75 76 static 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, 80 ASN1_TLC *ctx); 81 82 static int asn1_template_ex_d2i(ASN1_VALUE **pval, 83 const unsigned char **in, long len, 84 const ASN1_TEMPLATE *tt, char opt, 85 ASN1_TLC *ctx); 86 static int asn1_template_noexp_d2i(ASN1_VALUE **val, 87 const unsigned char **in, long len, 88 const ASN1_TEMPLATE *tt, char opt, 89 ASN1_TLC *ctx); 90 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 91 const unsigned char **in, long len, 92 const ASN1_ITEM *it, 93 int tag, int aclass, char opt, ASN1_TLC *ctx); 94 95 /* Table to convert tags to bit values, used for MSTRING type */ 96 static unsigned long tag2bit[32] = { 97 0, 0, 0, B_ASN1_BIT_STRING, /* tags 0 - 3 */ 98 B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,/* tags 4- 7 */ 99 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags 8-11 */ 100 B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */ 101 0, 0, B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */ 102 B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING, /* tags 20-22 */ 103 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, /* tags 23-24 */ 104 B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING, /* tags 25-27 */ 105 B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */ 106 }; 107 108 unsigned long ASN1_tag2bit(int tag) 109 { 110 if ((tag < 0) || (tag > 30)) return 0; 111 return tag2bit[tag]; 112 } 113 114 /* Macro to initialize and invalidate the cache */ 115 116 #define asn1_tlc_clear(c) if (c) (c)->valid = 0 117 118 /* Decode an ASN1 item, this currently behaves just 119 * like a standard 'd2i' function. 'in' points to 120 * a buffer to read the data from, in future we will 121 * have more advanced versions that can input data 122 * a piece at a time and this will simply be a special 123 * case. 124 */ 125 126 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval, 127 const unsigned char **in, long len, const ASN1_ITEM *it) 128 { 129 ASN1_TLC c; 130 ASN1_VALUE *ptmpval = NULL; 131 if (!pval) 132 pval = &ptmpval; 133 asn1_tlc_clear(&c); 134 if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 135 return *pval; 136 return NULL; 137 } 138 139 int ASN1_template_d2i(ASN1_VALUE **pval, 140 const unsigned char **in, long len, const ASN1_TEMPLATE *tt) 141 { 142 ASN1_TLC c; 143 asn1_tlc_clear(&c); 144 return asn1_template_ex_d2i(pval, in, len, tt, 0, &c); 145 } 146 147 148 /* Decode an item, taking care of IMPLICIT tagging, if any. 149 * If 'opt' set and tag mismatch return -1 to handle OPTIONAL 150 */ 151 152 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len, 153 const ASN1_ITEM *it, 154 int tag, int aclass, char opt, ASN1_TLC *ctx) 155 { 156 const ASN1_TEMPLATE *tt, *errtt = NULL; 157 const ASN1_COMPAT_FUNCS *cf; 158 const ASN1_EXTERN_FUNCS *ef; 159 const ASN1_AUX *aux = it->funcs; 160 ASN1_aux_cb *asn1_cb; 161 const unsigned char *p, *q; 162 unsigned char *wp=NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */ 163 unsigned char imphack = 0, oclass; 164 char seq_eoc, seq_nolen, cst, isopt; 165 long tmplen; 166 int i; 167 int otag; 168 int ret = 0; 169 ASN1_VALUE *pchval, **pchptr, *ptmpval; 170 if (!pval) 171 return 0; 172 if (aux && aux->asn1_cb) 173 asn1_cb = aux->asn1_cb; 174 else asn1_cb = 0; 175 176 switch(it->itype) 177 { 178 case ASN1_ITYPE_PRIMITIVE: 179 if (it->templates) 180 { 181 /* tagging or OPTIONAL is currently illegal on an item 182 * template because the flags can't get passed down. 183 * In practice this isn't a problem: we include the 184 * relevant flags from the item template in the 185 * template itself. 186 */ 187 if ((tag != -1) || opt) 188 { 189 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 190 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE); 191 goto err; 192 } 193 return asn1_template_ex_d2i(pval, in, len, 194 it->templates, opt, ctx); 195 } 196 return asn1_d2i_ex_primitive(pval, in, len, it, 197 tag, aclass, opt, ctx); 198 break; 199 200 case ASN1_ITYPE_MSTRING: 201 p = *in; 202 /* Just read in tag and class */ 203 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL, 204 &p, len, -1, 0, 1, ctx); 205 if (!ret) 206 { 207 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 208 ERR_R_NESTED_ASN1_ERROR); 209 goto err; 210 } 211 212 /* Must be UNIVERSAL class */ 213 if (oclass != V_ASN1_UNIVERSAL) 214 { 215 /* If OPTIONAL, assume this is OK */ 216 if (opt) return -1; 217 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 218 ASN1_R_MSTRING_NOT_UNIVERSAL); 219 goto err; 220 } 221 /* Check tag matches bit map */ 222 if (!(ASN1_tag2bit(otag) & it->utype)) 223 { 224 /* If OPTIONAL, assume this is OK */ 225 if (opt) 226 return -1; 227 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 228 ASN1_R_MSTRING_WRONG_TAG); 229 goto err; 230 } 231 return asn1_d2i_ex_primitive(pval, in, len, 232 it, otag, 0, 0, ctx); 233 234 case ASN1_ITYPE_EXTERN: 235 /* Use new style d2i */ 236 ef = it->funcs; 237 return ef->asn1_ex_d2i(pval, in, len, 238 it, tag, aclass, opt, ctx); 239 240 case ASN1_ITYPE_COMPAT: 241 /* we must resort to old style evil hackery */ 242 cf = it->funcs; 243 244 /* If OPTIONAL see if it is there */ 245 if (opt) 246 { 247 int exptag; 248 p = *in; 249 if (tag == -1) 250 exptag = it->utype; 251 else exptag = tag; 252 /* Don't care about anything other than presence 253 * of expected tag */ 254 255 ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL, 256 &p, len, exptag, aclass, 1, ctx); 257 if (!ret) 258 { 259 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 260 ERR_R_NESTED_ASN1_ERROR); 261 goto err; 262 } 263 if (ret == -1) 264 return -1; 265 } 266 267 /* This is the old style evil hack IMPLICIT handling: 268 * since the underlying code is expecting a tag and 269 * class other than the one present we change the 270 * buffer temporarily then change it back afterwards. 271 * This doesn't and never did work for tags > 30. 272 * 273 * Yes this is *horrible* but it is only needed for 274 * old style d2i which will hopefully not be around 275 * for much longer. 276 * FIXME: should copy the buffer then modify it so 277 * the input buffer can be const: we should *always* 278 * copy because the old style d2i might modify the 279 * buffer. 280 */ 281 282 if (tag != -1) 283 { 284 wp = *(unsigned char **)in; 285 imphack = *wp; 286 *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED) 287 | it->utype); 288 } 289 290 ptmpval = cf->asn1_d2i(pval, in, len); 291 292 if (tag != -1) 293 *wp = imphack; 294 295 if (ptmpval) 296 return 1; 297 298 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR); 299 goto err; 300 301 302 case ASN1_ITYPE_CHOICE: 303 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) 304 goto auxerr; 305 306 /* Allocate structure */ 307 if (!*pval && !ASN1_item_ex_new(pval, it)) 308 { 309 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 310 ERR_R_NESTED_ASN1_ERROR); 311 goto err; 312 } 313 /* CHOICE type, try each possibility in turn */ 314 pchval = NULL; 315 p = *in; 316 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++) 317 { 318 pchptr = asn1_get_field_ptr(pval, tt); 319 /* We mark field as OPTIONAL so its absence 320 * can be recognised. 321 */ 322 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx); 323 /* If field not present, try the next one */ 324 if (ret == -1) 325 continue; 326 /* If positive return, read OK, break loop */ 327 if (ret > 0) 328 break; 329 /* Otherwise must be an ASN1 parsing error */ 330 errtt = tt; 331 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 332 ERR_R_NESTED_ASN1_ERROR); 333 goto err; 334 } 335 336 /* Did we fall off the end without reading anything? */ 337 if (i == it->tcount) 338 { 339 /* If OPTIONAL, this is OK */ 340 if (opt) 341 { 342 /* Free and zero it */ 343 ASN1_item_ex_free(pval, it); 344 return -1; 345 } 346 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 347 ASN1_R_NO_MATCHING_CHOICE_TYPE); 348 goto err; 349 } 350 351 asn1_set_choice_selector(pval, i, it); 352 *in = p; 353 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) 354 goto auxerr; 355 return 1; 356 357 case ASN1_ITYPE_NDEF_SEQUENCE: 358 case ASN1_ITYPE_SEQUENCE: 359 p = *in; 360 tmplen = len; 361 362 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */ 363 if (tag == -1) 364 { 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 { 373 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 374 ERR_R_NESTED_ASN1_ERROR); 375 goto err; 376 } 377 else if (ret == -1) 378 return -1; 379 if (aux && (aux->flags & ASN1_AFLG_BROKEN)) 380 { 381 len = tmplen - (p - *in); 382 seq_nolen = 1; 383 } 384 /* If indefinite we don't do a length check */ 385 else seq_nolen = seq_eoc; 386 if (!cst) 387 { 388 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 389 ASN1_R_SEQUENCE_NOT_CONSTRUCTED); 390 goto err; 391 } 392 393 if (!*pval && !ASN1_item_ex_new(pval, it)) 394 { 395 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 396 ERR_R_NESTED_ASN1_ERROR); 397 goto err; 398 } 399 400 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it)) 401 goto auxerr; 402 403 /* Get each field entry */ 404 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) 405 { 406 const ASN1_TEMPLATE *seqtt; 407 ASN1_VALUE **pseqval; 408 seqtt = asn1_do_adb(pval, tt, 1); 409 if (!seqtt) 410 goto err; 411 pseqval = asn1_get_field_ptr(pval, seqtt); 412 /* Have we ran out of data? */ 413 if (!len) 414 break; 415 q = p; 416 if (asn1_check_eoc(&p, len)) 417 { 418 if (!seq_eoc) 419 { 420 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 421 ASN1_R_UNEXPECTED_EOC); 422 goto err; 423 } 424 len -= p - q; 425 seq_eoc = 0; 426 q = p; 427 break; 428 } 429 /* This determines the OPTIONAL flag value. The field 430 * cannot be omitted if it is the last of a SEQUENCE 431 * and there is still data to be read. This isn't 432 * strictly necessary but it increases efficiency in 433 * some cases. 434 */ 435 if (i == (it->tcount - 1)) 436 isopt = 0; 437 else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL); 438 /* attempt to read in field, allowing each to be 439 * OPTIONAL */ 440 441 ret = asn1_template_ex_d2i(pseqval, &p, len, 442 seqtt, isopt, ctx); 443 if (!ret) 444 { 445 errtt = seqtt; 446 goto err; 447 } 448 else if (ret == -1) 449 { 450 /* OPTIONAL component absent. 451 * Free and zero the field. 452 */ 453 ASN1_template_free(pseqval, seqtt); 454 continue; 455 } 456 /* Update length */ 457 len -= p - q; 458 } 459 460 /* Check for EOC if expecting one */ 461 if (seq_eoc && !asn1_check_eoc(&p, len)) 462 { 463 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC); 464 goto err; 465 } 466 /* Check all data read */ 467 if (!seq_nolen && len) 468 { 469 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 470 ASN1_R_SEQUENCE_LENGTH_MISMATCH); 471 goto err; 472 } 473 474 /* If we get here we've got no more data in the SEQUENCE, 475 * however we may not have read all fields so check all 476 * remaining are OPTIONAL and clear any that are. 477 */ 478 for (; i < it->tcount; tt++, i++) 479 { 480 const ASN1_TEMPLATE *seqtt; 481 seqtt = asn1_do_adb(pval, tt, 1); 482 if (!seqtt) 483 goto err; 484 if (seqtt->flags & ASN1_TFLG_OPTIONAL) 485 { 486 ASN1_VALUE **pseqval; 487 pseqval = asn1_get_field_ptr(pval, seqtt); 488 ASN1_template_free(pseqval, seqtt); 489 } 490 else 491 { 492 errtt = seqtt; 493 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, 494 ASN1_R_FIELD_MISSING); 495 goto err; 496 } 497 } 498 /* Save encoding */ 499 if (!asn1_enc_save(pval, *in, p - *in, it)) 500 goto auxerr; 501 *in = p; 502 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it)) 503 goto auxerr; 504 return 1; 505 506 default: 507 return 0; 508 } 509 auxerr: 510 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR); 511 err: 512 ASN1_item_ex_free(pval, it); 513 if (errtt) 514 ERR_add_error_data(4, "Field=", errtt->field_name, 515 ", Type=", it->sname); 516 else 517 ERR_add_error_data(2, "Type=", it->sname); 518 return 0; 519 } 520 521 /* Templates are handled with two separate functions. 522 * One handles any EXPLICIT tag and the other handles the rest. 523 */ 524 525 static int asn1_template_ex_d2i(ASN1_VALUE **val, 526 const unsigned char **in, long inlen, 527 const ASN1_TEMPLATE *tt, char opt, 528 ASN1_TLC *ctx) 529 { 530 int flags, aclass; 531 int ret; 532 long len; 533 const unsigned char *p, *q; 534 char exp_eoc; 535 if (!val) 536 return 0; 537 flags = tt->flags; 538 aclass = flags & ASN1_TFLG_TAG_CLASS; 539 540 p = *in; 541 542 /* Check if EXPLICIT tag expected */ 543 if (flags & ASN1_TFLG_EXPTAG) 544 { 545 char cst; 546 /* Need to work out amount of data available to the inner 547 * content and where it starts: so read in EXPLICIT header to 548 * get the info. 549 */ 550 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst, 551 &p, inlen, tt->tag, aclass, opt, ctx); 552 q = p; 553 if (!ret) 554 { 555 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 556 ERR_R_NESTED_ASN1_ERROR); 557 return 0; 558 } 559 else if (ret == -1) 560 return -1; 561 if (!cst) 562 { 563 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 564 ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED); 565 return 0; 566 } 567 /* We've found the field so it can't be OPTIONAL now */ 568 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx); 569 if (!ret) 570 { 571 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 572 ERR_R_NESTED_ASN1_ERROR); 573 return 0; 574 } 575 /* We read the field in OK so update length */ 576 len -= p - q; 577 if (exp_eoc) 578 { 579 /* If NDEF we must have an EOC here */ 580 if (!asn1_check_eoc(&p, len)) 581 { 582 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 583 ASN1_R_MISSING_EOC); 584 goto err; 585 } 586 } 587 else 588 { 589 /* Otherwise we must hit the EXPLICIT tag end or its 590 * an error */ 591 if (len) 592 { 593 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, 594 ASN1_R_EXPLICIT_LENGTH_MISMATCH); 595 goto err; 596 } 597 } 598 } 599 else 600 return asn1_template_noexp_d2i(val, in, inlen, 601 tt, opt, ctx); 602 603 *in = p; 604 return 1; 605 606 err: 607 ASN1_template_free(val, tt); 608 *val = NULL; 609 return 0; 610 } 611 612 static int asn1_template_noexp_d2i(ASN1_VALUE **val, 613 const unsigned char **in, long len, 614 const ASN1_TEMPLATE *tt, char opt, 615 ASN1_TLC *ctx) 616 { 617 int flags, aclass; 618 int ret; 619 const unsigned char *p, *q; 620 if (!val) 621 return 0; 622 flags = tt->flags; 623 aclass = flags & ASN1_TFLG_TAG_CLASS; 624 625 p = *in; 626 q = p; 627 628 if (flags & ASN1_TFLG_SK_MASK) 629 { 630 /* SET OF, SEQUENCE OF */ 631 int sktag, skaclass; 632 char sk_eoc; 633 /* First work out expected inner tag value */ 634 if (flags & ASN1_TFLG_IMPTAG) 635 { 636 sktag = tt->tag; 637 skaclass = aclass; 638 } 639 else 640 { 641 skaclass = V_ASN1_UNIVERSAL; 642 if (flags & ASN1_TFLG_SET_OF) 643 sktag = V_ASN1_SET; 644 else 645 sktag = V_ASN1_SEQUENCE; 646 } 647 /* Get the tag */ 648 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL, 649 &p, len, sktag, skaclass, opt, ctx); 650 if (!ret) 651 { 652 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 653 ERR_R_NESTED_ASN1_ERROR); 654 return 0; 655 } 656 else if (ret == -1) 657 return -1; 658 if (!*val) 659 *val = (ASN1_VALUE *)sk_new_null(); 660 else 661 { 662 /* We've got a valid STACK: free up any items present */ 663 STACK *sktmp = (STACK *)*val; 664 ASN1_VALUE *vtmp; 665 while(sk_num(sktmp) > 0) 666 { 667 vtmp = (ASN1_VALUE *)sk_pop(sktmp); 668 ASN1_item_ex_free(&vtmp, 669 ASN1_ITEM_ptr(tt->item)); 670 } 671 } 672 673 if (!*val) 674 { 675 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 676 ERR_R_MALLOC_FAILURE); 677 goto err; 678 } 679 680 /* Read as many items as we can */ 681 while(len > 0) 682 { 683 ASN1_VALUE *skfield; 684 q = p; 685 /* See if EOC found */ 686 if (asn1_check_eoc(&p, len)) 687 { 688 if (!sk_eoc) 689 { 690 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 691 ASN1_R_UNEXPECTED_EOC); 692 goto err; 693 } 694 len -= p - q; 695 sk_eoc = 0; 696 break; 697 } 698 skfield = NULL; 699 if (!ASN1_item_ex_d2i(&skfield, &p, len, 700 ASN1_ITEM_ptr(tt->item), 701 -1, 0, 0, ctx)) 702 { 703 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 704 ERR_R_NESTED_ASN1_ERROR); 705 goto err; 706 } 707 len -= p - q; 708 if (!sk_push((STACK *)*val, (char *)skfield)) 709 { 710 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 711 ERR_R_MALLOC_FAILURE); 712 goto err; 713 } 714 } 715 if (sk_eoc) 716 { 717 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC); 718 goto err; 719 } 720 } 721 else if (flags & ASN1_TFLG_IMPTAG) 722 { 723 /* IMPLICIT tagging */ 724 ret = ASN1_item_ex_d2i(val, &p, len, 725 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx); 726 if (!ret) 727 { 728 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 729 ERR_R_NESTED_ASN1_ERROR); 730 goto err; 731 } 732 else if (ret == -1) 733 return -1; 734 } 735 else 736 { 737 /* Nothing special */ 738 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item), 739 -1, 0, opt, ctx); 740 if (!ret) 741 { 742 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, 743 ERR_R_NESTED_ASN1_ERROR); 744 goto err; 745 } 746 else if (ret == -1) 747 return -1; 748 } 749 750 *in = p; 751 return 1; 752 753 err: 754 ASN1_template_free(val, tt); 755 *val = NULL; 756 return 0; 757 } 758 759 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval, 760 const unsigned char **in, long inlen, 761 const ASN1_ITEM *it, 762 int tag, int aclass, char opt, ASN1_TLC *ctx) 763 { 764 int ret = 0, utype; 765 long plen; 766 char cst, inf, free_cont = 0; 767 const unsigned char *p; 768 BUF_MEM buf; 769 const unsigned char *cont = NULL; 770 long len; 771 if (!pval) 772 { 773 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL); 774 return 0; /* Should never happen */ 775 } 776 777 if (it->itype == ASN1_ITYPE_MSTRING) 778 { 779 utype = tag; 780 tag = -1; 781 } 782 else 783 utype = it->utype; 784 785 if (utype == V_ASN1_ANY) 786 { 787 /* If type is ANY need to figure out type from tag */ 788 unsigned char oclass; 789 if (tag >= 0) 790 { 791 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 792 ASN1_R_ILLEGAL_TAGGED_ANY); 793 return 0; 794 } 795 if (opt) 796 { 797 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 798 ASN1_R_ILLEGAL_OPTIONAL_ANY); 799 return 0; 800 } 801 p = *in; 802 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL, 803 &p, inlen, -1, 0, 0, ctx); 804 if (!ret) 805 { 806 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 807 ERR_R_NESTED_ASN1_ERROR); 808 return 0; 809 } 810 if (oclass != V_ASN1_UNIVERSAL) 811 utype = V_ASN1_OTHER; 812 } 813 if (tag == -1) 814 { 815 tag = utype; 816 aclass = V_ASN1_UNIVERSAL; 817 } 818 p = *in; 819 /* Check header */ 820 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst, 821 &p, inlen, tag, aclass, opt, ctx); 822 if (!ret) 823 { 824 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR); 825 return 0; 826 } 827 else if (ret == -1) 828 return -1; 829 /* SEQUENCE, SET and "OTHER" are left in encoded form */ 830 if ((utype == V_ASN1_SEQUENCE) 831 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) 832 { 833 /* Clear context cache for type OTHER because the auto clear 834 * when we have a exact match wont work 835 */ 836 if (utype == V_ASN1_OTHER) 837 { 838 asn1_tlc_clear(ctx); 839 } 840 /* SEQUENCE and SET must be constructed */ 841 else if (!cst) 842 { 843 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 844 ASN1_R_TYPE_NOT_CONSTRUCTED); 845 return 0; 846 } 847 848 cont = *in; 849 /* If indefinite length constructed find the real end */ 850 if (inf) 851 { 852 if (!asn1_find_end(&p, plen, inf)) 853 goto err; 854 len = p - cont; 855 } 856 else 857 { 858 len = p - cont + plen; 859 p += plen; 860 buf.data = NULL; 861 } 862 } 863 else if (cst) 864 { 865 buf.length = 0; 866 buf.max = 0; 867 buf.data = NULL; 868 /* Should really check the internal tags are correct but 869 * some things may get this wrong. The relevant specs 870 * say that constructed string types should be OCTET STRINGs 871 * internally irrespective of the type. So instead just check 872 * for UNIVERSAL class and ignore the tag. 873 */ 874 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL)) 875 goto err; 876 len = buf.length; 877 /* Append a final null to string */ 878 if (!BUF_MEM_grow_clean(&buf, len + 1)) 879 { 880 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, 881 ERR_R_MALLOC_FAILURE); 882 return 0; 883 } 884 buf.data[len] = 0; 885 cont = (const unsigned char *)buf.data; 886 free_cont = 1; 887 } 888 else 889 { 890 cont = p; 891 len = plen; 892 p += plen; 893 } 894 895 /* We now have content length and type: translate into a structure */ 896 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it)) 897 goto err; 898 899 *in = p; 900 ret = 1; 901 err: 902 if (free_cont && buf.data) OPENSSL_free(buf.data); 903 return ret; 904 } 905 906 /* Translate ASN1 content octets into a structure */ 907 908 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 909 int utype, char *free_cont, const ASN1_ITEM *it) 910 { 911 ASN1_VALUE **opval = NULL; 912 ASN1_STRING *stmp; 913 ASN1_TYPE *typ = NULL; 914 int ret = 0; 915 const ASN1_PRIMITIVE_FUNCS *pf; 916 ASN1_INTEGER **tint; 917 pf = it->funcs; 918 919 if (pf && pf->prim_c2i) 920 return pf->prim_c2i(pval, cont, len, utype, free_cont, it); 921 /* If ANY type clear type and set pointer to internal value */ 922 if (it->utype == V_ASN1_ANY) 923 { 924 if (!*pval) 925 { 926 typ = ASN1_TYPE_new(); 927 *pval = (ASN1_VALUE *)typ; 928 } 929 else 930 typ = (ASN1_TYPE *)*pval; 931 932 if (utype != typ->type) 933 ASN1_TYPE_set(typ, utype, NULL); 934 opval = pval; 935 pval = (ASN1_VALUE **)&typ->value.ptr; 936 } 937 switch(utype) 938 { 939 case V_ASN1_OBJECT: 940 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len)) 941 goto err; 942 break; 943 944 case V_ASN1_NULL: 945 if (len) 946 { 947 ASN1err(ASN1_F_ASN1_EX_C2I, 948 ASN1_R_NULL_IS_WRONG_LENGTH); 949 goto err; 950 } 951 *pval = (ASN1_VALUE *)1; 952 break; 953 954 case V_ASN1_BOOLEAN: 955 if (len != 1) 956 { 957 ASN1err(ASN1_F_ASN1_EX_C2I, 958 ASN1_R_BOOLEAN_IS_WRONG_LENGTH); 959 goto err; 960 } 961 else 962 { 963 ASN1_BOOLEAN *tbool; 964 tbool = (ASN1_BOOLEAN *)pval; 965 *tbool = *cont; 966 } 967 break; 968 969 case V_ASN1_BIT_STRING: 970 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len)) 971 goto err; 972 break; 973 974 case V_ASN1_INTEGER: 975 case V_ASN1_NEG_INTEGER: 976 case V_ASN1_ENUMERATED: 977 case V_ASN1_NEG_ENUMERATED: 978 tint = (ASN1_INTEGER **)pval; 979 if (!c2i_ASN1_INTEGER(tint, &cont, len)) 980 goto err; 981 /* Fixup type to match the expected form */ 982 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG); 983 break; 984 985 case V_ASN1_OCTET_STRING: 986 case V_ASN1_NUMERICSTRING: 987 case V_ASN1_PRINTABLESTRING: 988 case V_ASN1_T61STRING: 989 case V_ASN1_VIDEOTEXSTRING: 990 case V_ASN1_IA5STRING: 991 case V_ASN1_UTCTIME: 992 case V_ASN1_GENERALIZEDTIME: 993 case V_ASN1_GRAPHICSTRING: 994 case V_ASN1_VISIBLESTRING: 995 case V_ASN1_GENERALSTRING: 996 case V_ASN1_UNIVERSALSTRING: 997 case V_ASN1_BMPSTRING: 998 case V_ASN1_UTF8STRING: 999 case V_ASN1_OTHER: 1000 case V_ASN1_SET: 1001 case V_ASN1_SEQUENCE: 1002 default: 1003 /* All based on ASN1_STRING and handled the same */ 1004 if (!*pval) 1005 { 1006 stmp = ASN1_STRING_type_new(utype); 1007 if (!stmp) 1008 { 1009 ASN1err(ASN1_F_ASN1_EX_C2I, 1010 ERR_R_MALLOC_FAILURE); 1011 goto err; 1012 } 1013 *pval = (ASN1_VALUE *)stmp; 1014 } 1015 else 1016 { 1017 stmp = (ASN1_STRING *)*pval; 1018 stmp->type = utype; 1019 } 1020 /* If we've already allocated a buffer use it */ 1021 if (*free_cont) 1022 { 1023 if (stmp->data) 1024 OPENSSL_free(stmp->data); 1025 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */ 1026 stmp->length = len; 1027 *free_cont = 0; 1028 } 1029 else 1030 { 1031 if (!ASN1_STRING_set(stmp, cont, len)) 1032 { 1033 ASN1err(ASN1_F_ASN1_EX_C2I, 1034 ERR_R_MALLOC_FAILURE); 1035 ASN1_STRING_free(stmp); 1036 *pval = NULL; 1037 goto err; 1038 } 1039 } 1040 break; 1041 } 1042 /* If ASN1_ANY and NULL type fix up value */ 1043 if (typ && (utype == V_ASN1_NULL)) 1044 typ->value.ptr = NULL; 1045 1046 ret = 1; 1047 err: 1048 if (!ret) 1049 { 1050 ASN1_TYPE_free(typ); 1051 if (opval) 1052 *opval = NULL; 1053 } 1054 return ret; 1055 } 1056 1057 1058 /* This function finds the end of an ASN1 structure when passed its maximum 1059 * length, whether it is indefinite length and a pointer to the content. 1060 * This is more efficient than calling asn1_collect because it does not 1061 * recurse on each indefinite length header. 1062 */ 1063 1064 static int asn1_find_end(const unsigned char **in, long len, char inf) 1065 { 1066 int expected_eoc; 1067 long plen; 1068 const unsigned char *p = *in, *q; 1069 /* If not indefinite length constructed just add length */ 1070 if (inf == 0) 1071 { 1072 *in += len; 1073 return 1; 1074 } 1075 expected_eoc = 1; 1076 /* Indefinite length constructed form. Find the end when enough EOCs 1077 * are found. If more indefinite length constructed headers 1078 * are encountered increment the expected eoc count otherwise just 1079 * skip to the end of the data. 1080 */ 1081 while (len > 0) 1082 { 1083 if(asn1_check_eoc(&p, len)) 1084 { 1085 expected_eoc--; 1086 if (expected_eoc == 0) 1087 break; 1088 len -= 2; 1089 continue; 1090 } 1091 q = p; 1092 /* Just read in a header: only care about the length */ 1093 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len, 1094 -1, 0, 0, NULL)) 1095 { 1096 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR); 1097 return 0; 1098 } 1099 if (inf) 1100 expected_eoc++; 1101 else 1102 p += plen; 1103 len -= p - q; 1104 } 1105 if (expected_eoc) 1106 { 1107 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC); 1108 return 0; 1109 } 1110 *in = p; 1111 return 1; 1112 } 1113 /* This function collects the asn1 data from a constructred string 1114 * type into a buffer. The values of 'in' and 'len' should refer 1115 * to the contents of the constructed type and 'inf' should be set 1116 * if it is indefinite length. 1117 */ 1118 1119 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len, 1120 char inf, int tag, int aclass) 1121 { 1122 const unsigned char *p, *q; 1123 long plen; 1124 char cst, ininf; 1125 p = *in; 1126 inf &= 1; 1127 /* If no buffer and not indefinite length constructed just pass over 1128 * the encoded data */ 1129 if (!buf && !inf) 1130 { 1131 *in += len; 1132 return 1; 1133 } 1134 while(len > 0) 1135 { 1136 q = p; 1137 /* Check for EOC */ 1138 if (asn1_check_eoc(&p, len)) 1139 { 1140 /* EOC is illegal outside indefinite length 1141 * constructed form */ 1142 if (!inf) 1143 { 1144 ASN1err(ASN1_F_ASN1_COLLECT, 1145 ASN1_R_UNEXPECTED_EOC); 1146 return 0; 1147 } 1148 inf = 0; 1149 break; 1150 } 1151 1152 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p, 1153 len, tag, aclass, 0, NULL)) 1154 { 1155 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR); 1156 return 0; 1157 } 1158 1159 /* If indefinite length constructed update max length */ 1160 if (cst) 1161 { 1162 #ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS 1163 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass)) 1164 return 0; 1165 #else 1166 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING); 1167 return 0; 1168 #endif 1169 } 1170 else if (!collect_data(buf, &p, plen)) 1171 return 0; 1172 len -= p - q; 1173 } 1174 if (inf) 1175 { 1176 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC); 1177 return 0; 1178 } 1179 *in = p; 1180 return 1; 1181 } 1182 1183 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen) 1184 { 1185 int len; 1186 if (buf) 1187 { 1188 len = buf->length; 1189 if (!BUF_MEM_grow_clean(buf, len + plen)) 1190 { 1191 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE); 1192 return 0; 1193 } 1194 memcpy(buf->data + len, *p, plen); 1195 } 1196 *p += plen; 1197 return 1; 1198 } 1199 1200 /* Check for ASN1 EOC and swallow it if found */ 1201 1202 static int asn1_check_eoc(const unsigned char **in, long len) 1203 { 1204 const unsigned char *p; 1205 if (len < 2) return 0; 1206 p = *in; 1207 if (!p[0] && !p[1]) 1208 { 1209 *in += 2; 1210 return 1; 1211 } 1212 return 0; 1213 } 1214 1215 /* Check an ASN1 tag and length: a bit like ASN1_get_object 1216 * but it sets the length for indefinite length constructed 1217 * form, we don't know the exact length but we can set an 1218 * upper bound to the amount of data available minus the 1219 * header length just read. 1220 */ 1221 1222 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass, 1223 char *inf, char *cst, 1224 const unsigned char **in, long len, 1225 int exptag, int expclass, char opt, 1226 ASN1_TLC *ctx) 1227 { 1228 int i; 1229 int ptag, pclass; 1230 long plen; 1231 const unsigned char *p, *q; 1232 p = *in; 1233 q = p; 1234 1235 if (ctx && ctx->valid) 1236 { 1237 i = ctx->ret; 1238 plen = ctx->plen; 1239 pclass = ctx->pclass; 1240 ptag = ctx->ptag; 1241 p += ctx->hdrlen; 1242 } 1243 else 1244 { 1245 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len); 1246 if (ctx) 1247 { 1248 ctx->ret = i; 1249 ctx->plen = plen; 1250 ctx->pclass = pclass; 1251 ctx->ptag = ptag; 1252 ctx->hdrlen = p - q; 1253 ctx->valid = 1; 1254 /* If definite length, and no error, length + 1255 * header can't exceed total amount of data available. 1256 */ 1257 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) 1258 { 1259 ASN1err(ASN1_F_ASN1_CHECK_TLEN, 1260 ASN1_R_TOO_LONG); 1261 asn1_tlc_clear(ctx); 1262 return 0; 1263 } 1264 } 1265 } 1266 1267 if (i & 0x80) 1268 { 1269 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER); 1270 asn1_tlc_clear(ctx); 1271 return 0; 1272 } 1273 if (exptag >= 0) 1274 { 1275 if ((exptag != ptag) || (expclass != pclass)) 1276 { 1277 /* If type is OPTIONAL, not an error: 1278 * indicate missing type. 1279 */ 1280 if (opt) return -1; 1281 asn1_tlc_clear(ctx); 1282 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG); 1283 return 0; 1284 } 1285 /* We have a tag and class match: 1286 * assume we are going to do something with it */ 1287 asn1_tlc_clear(ctx); 1288 } 1289 1290 if (i & 1) 1291 plen = len - (p - q); 1292 1293 if (inf) 1294 *inf = i & 1; 1295 1296 if (cst) 1297 *cst = i & V_ASN1_CONSTRUCTED; 1298 1299 if (olen) 1300 *olen = plen; 1301 1302 if (oclass) 1303 *oclass = pclass; 1304 1305 if (otag) 1306 *otag = ptag; 1307 1308 *in = p; 1309 return 1; 1310 } 1311