crypto/openssl/crypto/asn1/tasn_dec.c

   1 /* tasn_dec.c */
   2 /* Written by Dr Stephen N Henson (steve@openssl.org) 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, int depth);
  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 const 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 B_ASN1_SEQUENCE,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         c.valid = 0;
 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         c.valid = 0;
 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 = NULL, *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 **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                         if (p == NULL)
 287                                 {
 288                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 289                                         ERR_R_NESTED_ASN1_ERROR);
 290                                 goto err;
 291                                 }
 292                         *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
 293                                                                 | it->utype);
 294                         }
 295
 296                 ptmpval = cf->asn1_d2i(pval, in, len);
 297
 298                 if (tag != -1)
 299                         *wp = imphack;
 300
 301                 if (ptmpval)
 302                         return 1;
 303
 304                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
 305                 goto err;
 306
 307
 308                 case ASN1_ITYPE_CHOICE:
 309                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
 310                                 goto auxerr;
 311
 312                 if (*pval) {
 313                         /* Free up and zero CHOICE value if initialised */
 314                         i = asn1_get_choice_selector(pval, it);
 315                         if ((i >= 0) && (i < it->tcount)) {
 316                                 tt = it->templates + i;
 317                                 pchptr = asn1_get_field_ptr(pval, tt);
 318                                 ASN1_template_free(pchptr, tt);
 319                                 asn1_set_choice_selector(pval, -1, it);
 320                         }
 321                 } else if (!ASN1_item_ex_new(pval, it)) {
 322                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 323                                                 ERR_R_NESTED_ASN1_ERROR);
 324                         goto err;
 325                 }
 326                 /* CHOICE type, try each possibility in turn */
 327                 p = *in;
 328                 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
 329                         {
 330                         pchptr = asn1_get_field_ptr(pval, tt);
 331                         /* We mark field as OPTIONAL so its absence
 332                          * can be recognised.
 333                          */
 334                         ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
 335                         /* If field not present, try the next one */
 336                         if (ret == -1)
 337                                 continue;
 338                         /* If positive return, read OK, break loop */
 339                         if (ret > 0)
 340                                 break;
 341                         /* Otherwise must be an ASN1 parsing error */
 342                         errtt = tt;
 343                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 344                                                 ERR_R_NESTED_ASN1_ERROR);
 345                         goto err;
 346                         }
 347
 348                 /* Did we fall off the end without reading anything? */
 349                 if (i == it->tcount)
 350                         {
 351                         /* If OPTIONAL, this is OK */
 352                         if (opt)
 353                                 {
 354                                 /* Free and zero it */
 355                                 ASN1_item_ex_free(pval, it);
 356                                 return -1;
 357                                 }
 358                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 359                                         ASN1_R_NO_MATCHING_CHOICE_TYPE);
 360                         goto err;
 361                         }
 362
 363                 asn1_set_choice_selector(pval, i, it);
 364                 *in = p;
 365                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
 366                                 goto auxerr;
 367                 return 1;
 368
 369                 case ASN1_ITYPE_NDEF_SEQUENCE:
 370                 case ASN1_ITYPE_SEQUENCE:
 371                 p = *in;
 372                 tmplen = len;
 373
 374                 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
 375                 if (tag == -1)
 376                         {
 377                         tag = V_ASN1_SEQUENCE;
 378                         aclass = V_ASN1_UNIVERSAL;
 379                         }
 380                 /* Get SEQUENCE length and update len, p */
 381                 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
 382                                         &p, len, tag, aclass, opt, ctx);
 383                 if (!ret)
 384                         {
 385                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 386                                         ERR_R_NESTED_ASN1_ERROR);
 387                         goto err;
 388                         }
 389                 else if (ret == -1)
 390                         return -1;
 391                 if (aux && (aux->flags & ASN1_AFLG_BROKEN))
 392                         {
 393                         len = tmplen - (p - *in);
 394                         seq_nolen = 1;
 395                         }
 396                 /* If indefinite we don't do a length check */
 397                 else seq_nolen = seq_eoc;
 398                 if (!cst)
 399                         {
 400                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 401                                 ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
 402                         goto err;
 403                         }
 404
 405                 if (!*pval && !ASN1_item_ex_new(pval, it))
 406                         {
 407                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 408                                 ERR_R_NESTED_ASN1_ERROR);
 409                         goto err;
 410                         }
 411
 412                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
 413                                 goto auxerr;
 414
 415                 /* Free up and zero any ADB found */
 416                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
 417                         if (tt->flags & ASN1_TFLG_ADB_MASK) {
 418                                 const ASN1_TEMPLATE *seqtt;
 419                                 ASN1_VALUE **pseqval;
 420                                 seqtt = asn1_do_adb(pval, tt, 1);
 421                                 pseqval = asn1_get_field_ptr(pval, seqtt);
 422                                 ASN1_template_free(pseqval, seqtt);
 423                         }
 424                 }
 425
 426                 /* Get each field entry */
 427                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
 428                         {
 429                         const ASN1_TEMPLATE *seqtt;
 430                         ASN1_VALUE **pseqval;
 431                         seqtt = asn1_do_adb(pval, tt, 1);
 432                         if (!seqtt)
 433                                 goto err;
 434                         pseqval = asn1_get_field_ptr(pval, seqtt);
 435                         /* Have we ran out of data? */
 436                         if (!len)
 437                                 break;
 438                         q = p;
 439                         if (asn1_check_eoc(&p, len))
 440                                 {
 441                                 if (!seq_eoc)
 442                                         {
 443                                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 444                                                         ASN1_R_UNEXPECTED_EOC);
 445                                         goto err;
 446                                         }
 447                                 len -= p - q;
 448                                 seq_eoc = 0;
 449                                 q = p;
 450                                 break;
 451                                 }
 452                         /* This determines the OPTIONAL flag value. The field
 453                          * cannot be omitted if it is the last of a SEQUENCE
 454                          * and there is still data to be read. This isn't
 455                          * strictly necessary but it increases efficiency in
 456                          * some cases.
 457                          */
 458                         if (i == (it->tcount - 1))
 459                                 isopt = 0;
 460                         else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
 461                         /* attempt to read in field, allowing each to be
 462                          * OPTIONAL */
 463
 464                         ret = asn1_template_ex_d2i(pseqval, &p, len,
 465                                                         seqtt, isopt, ctx);
 466                         if (!ret)
 467                                 {
 468                                 errtt = seqtt;
 469                                 goto err;
 470                                 }
 471                         else if (ret == -1)
 472                                 {
 473                                 /* OPTIONAL component absent.
 474                                  * Free and zero the field.
 475                                  */
 476                                 ASN1_template_free(pseqval, seqtt);
 477                                 continue;
 478                                 }
 479                         /* Update length */
 480                         len -= p - q;
 481                         }
 482
 483                 /* Check for EOC if expecting one */
 484                 if (seq_eoc && !asn1_check_eoc(&p, len))
 485                         {
 486                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
 487                         goto err;
 488                         }
 489                 /* Check all data read */
 490                 if (!seq_nolen && len)
 491                         {
 492                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 493                                         ASN1_R_SEQUENCE_LENGTH_MISMATCH);
 494                         goto err;
 495                         }
 496
 497                 /* If we get here we've got no more data in the SEQUENCE,
 498                  * however we may not have read all fields so check all
 499                  * remaining are OPTIONAL and clear any that are.
 500                  */
 501                 for (; i < it->tcount; tt++, i++)
 502                         {
 503                         const ASN1_TEMPLATE *seqtt;
 504                         seqtt = asn1_do_adb(pval, tt, 1);
 505                         if (!seqtt)
 506                                 goto err;
 507                         if (seqtt->flags & ASN1_TFLG_OPTIONAL)
 508                                 {
 509                                 ASN1_VALUE **pseqval;
 510                                 pseqval = asn1_get_field_ptr(pval, seqtt);
 511                                 ASN1_template_free(pseqval, seqtt);
 512                                 }
 513                         else
 514                                 {
 515                                 errtt = seqtt;
 516                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 517                                                         ASN1_R_FIELD_MISSING);
 518                                 goto err;
 519                                 }
 520                         }
 521                 /* Save encoding */
 522                 if (!asn1_enc_save(pval, *in, p - *in, it))
 523                         goto auxerr;
 524                 *in = p;
 525                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
 526                                 goto auxerr;
 527                 return 1;
 528
 529                 default:
 530                 return 0;
 531                 }
 532         auxerr:
 533         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
 534         err:
 535         ASN1_item_ex_free(pval, it);
 536         if (errtt)
 537                 ERR_add_error_data(4, "Field=", errtt->field_name,
 538                                         ", Type=", it->sname);
 539         else
 540                 ERR_add_error_data(2, "Type=", it->sname);
 541         return 0;
 542         }
 543
 544 /* Templates are handled with two separate functions.
 545  * One handles any EXPLICIT tag and the other handles the rest.
 546  */
 547
 548 static int asn1_template_ex_d2i(ASN1_VALUE **val,
 549                                 const unsigned char **in, long inlen,
 550                                 const ASN1_TEMPLATE *tt, char opt,
 551                                                         ASN1_TLC *ctx)
 552         {
 553         int flags, aclass;
 554         int ret;
 555         long len;
 556         const unsigned char *p, *q;
 557         char exp_eoc;
 558         if (!val)
 559                 return 0;
 560         flags = tt->flags;
 561         aclass = flags & ASN1_TFLG_TAG_CLASS;
 562
 563         p = *in;
 564
 565         /* Check if EXPLICIT tag expected */
 566         if (flags & ASN1_TFLG_EXPTAG)
 567                 {
 568                 char cst;
 569                 /* Need to work out amount of data available to the inner
 570                  * content and where it starts: so read in EXPLICIT header to
 571                  * get the info.
 572                  */
 573                 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
 574                                         &p, inlen, tt->tag, aclass, opt, ctx);
 575                 q = p;
 576                 if (!ret)
 577                         {
 578                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 579                                         ERR_R_NESTED_ASN1_ERROR);
 580                         return 0;
 581                         }
 582                 else if (ret == -1)
 583                         return -1;
 584                 if (!cst)
 585                         {
 586                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 587                                         ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
 588                         return 0;
 589                         }
 590                 /* We've found the field so it can't be OPTIONAL now */
 591                 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
 592                 if (!ret)
 593                         {
 594                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 595                                         ERR_R_NESTED_ASN1_ERROR);
 596                         return 0;
 597                         }
 598                 /* We read the field in OK so update length */
 599                 len -= p - q;
 600                 if (exp_eoc)
 601                         {
 602                         /* If NDEF we must have an EOC here */
 603                         if (!asn1_check_eoc(&p, len))
 604                                 {
 605                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 606                                                 ASN1_R_MISSING_EOC);
 607                                 goto err;
 608                                 }
 609                         }
 610                 else
 611                         {
 612                         /* Otherwise we must hit the EXPLICIT tag end or its
 613                          * an error */
 614                         if (len)
 615                                 {
 616                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 617                                         ASN1_R_EXPLICIT_LENGTH_MISMATCH);
 618                                 goto err;
 619                                 }
 620                         }
 621                 }
 622                 else
 623                         return asn1_template_noexp_d2i(val, in, inlen,
 624                                                                 tt, opt, ctx);
 625
 626         *in = p;
 627         return 1;
 628
 629         err:
 630         ASN1_template_free(val, tt);
 631         return 0;
 632         }
 633
 634 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
 635                                 const unsigned char **in, long len,
 636                                 const ASN1_TEMPLATE *tt, char opt,
 637                                 ASN1_TLC *ctx)
 638         {
 639         int flags, aclass;
 640         int ret;
 641         const unsigned char *p, *q;
 642         if (!val)
 643                 return 0;
 644         flags = tt->flags;
 645         aclass = flags & ASN1_TFLG_TAG_CLASS;
 646
 647         p = *in;
 648         q = p;
 649
 650         if (flags & ASN1_TFLG_SK_MASK)
 651                 {
 652                 /* SET OF, SEQUENCE OF */
 653                 int sktag, skaclass;
 654                 char sk_eoc;
 655                 /* First work out expected inner tag value */
 656                 if (flags & ASN1_TFLG_IMPTAG)
 657                         {
 658                         sktag = tt->tag;
 659                         skaclass = aclass;
 660                         }
 661                 else
 662                         {
 663                         skaclass = V_ASN1_UNIVERSAL;
 664                         if (flags & ASN1_TFLG_SET_OF)
 665                                 sktag = V_ASN1_SET;
 666                         else
 667                                 sktag = V_ASN1_SEQUENCE;
 668                         }
 669                 /* Get the tag */
 670                 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
 671                                         &p, len, sktag, skaclass, opt, ctx);
 672                 if (!ret)
 673                         {
 674                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 675                                                 ERR_R_NESTED_ASN1_ERROR);
 676                         return 0;
 677                         }
 678                 else if (ret == -1)
 679                         return -1;
 680                 if (!*val)
 681                         *val = (ASN1_VALUE *)sk_new_null();
 682                 else
 683                         {
 684                         /* We've got a valid STACK: free up any items present */
 685                         STACK *sktmp = (STACK *)*val;
 686                         ASN1_VALUE *vtmp;
 687                         while(sk_num(sktmp) > 0)
 688                                 {
 689                                 vtmp = (ASN1_VALUE *)sk_pop(sktmp);
 690                                 ASN1_item_ex_free(&vtmp,
 691                                                 ASN1_ITEM_ptr(tt->item));
 692                                 }
 693                         }
 694
 695                 if (!*val)
 696                         {
 697                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 698                                                 ERR_R_MALLOC_FAILURE);
 699                         goto err;
 700                         }
 701
 702                 /* Read as many items as we can */
 703                 while(len > 0)
 704                         {
 705                         ASN1_VALUE *skfield;
 706                         q = p;
 707                         /* See if EOC found */
 708                         if (asn1_check_eoc(&p, len))
 709                                 {
 710                                 if (!sk_eoc)
 711                                         {
 712                                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 713                                                         ASN1_R_UNEXPECTED_EOC);
 714                                         goto err;
 715                                         }
 716                                 len -= p - q;
 717                                 sk_eoc = 0;
 718                                 break;
 719                                 }
 720                         skfield = NULL;
 721                         if (!ASN1_item_ex_d2i(&skfield, &p, len,
 722                                                 ASN1_ITEM_ptr(tt->item),
 723                                                 -1, 0, 0, ctx))
 724                                 {
 725                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 726                                         ERR_R_NESTED_ASN1_ERROR);
 727                                 goto err;
 728                                 }
 729                         len -= p - q;
 730                         if (!sk_push((STACK *)*val, (char *)skfield))
 731                                 {
 732                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 733                                                 ERR_R_MALLOC_FAILURE);
 734                                 goto err;
 735                                 }
 736                         }
 737                 if (sk_eoc)
 738                         {
 739                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
 740                         goto err;
 741                         }
 742                 }
 743         else if (flags & ASN1_TFLG_IMPTAG)
 744                 {
 745                 /* IMPLICIT tagging */
 746                 ret = ASN1_item_ex_d2i(val, &p, len,
 747                         ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
 748                 if (!ret)
 749                         {
 750                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 751                                                 ERR_R_NESTED_ASN1_ERROR);
 752                         goto err;
 753                         }
 754                 else if (ret == -1)
 755                         return -1;
 756                 }
 757         else
 758                 {
 759                 /* Nothing special */
 760                 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
 761                                                         -1, 0, opt, ctx);
 762                 if (!ret)
 763                         {
 764                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 765                                         ERR_R_NESTED_ASN1_ERROR);
 766                         goto err;
 767                         }
 768                 else if (ret == -1)
 769                         return -1;
 770                 }
 771
 772         *in = p;
 773         return 1;
 774
 775         err:
 776         ASN1_template_free(val, tt);
 777         return 0;
 778         }
 779
 780 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
 781                                 const unsigned char **in, long inlen,
 782                                 const ASN1_ITEM *it,
 783                                 int tag, int aclass, char opt, ASN1_TLC *ctx)
 784         {
 785         int ret = 0, utype;
 786         long plen;
 787         char cst, inf, free_cont = 0;
 788         const unsigned char *p;
 789         BUF_MEM buf;
 790         const unsigned char *cont = NULL;
 791         long len;
 792         if (!pval)
 793                 {
 794                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
 795                 return 0; /* Should never happen */
 796                 }
 797
 798         if (it->itype == ASN1_ITYPE_MSTRING)
 799                 {
 800                 utype = tag;
 801                 tag = -1;
 802                 }
 803         else
 804                 utype = it->utype;
 805
 806         if (utype == V_ASN1_ANY)
 807                 {
 808                 /* If type is ANY need to figure out type from tag */
 809                 unsigned char oclass;
 810                 if (tag >= 0)
 811                         {
 812                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 813                                         ASN1_R_ILLEGAL_TAGGED_ANY);
 814                         return 0;
 815                         }
 816                 if (opt)
 817                         {
 818                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 819                                         ASN1_R_ILLEGAL_OPTIONAL_ANY);
 820                         return 0;
 821                         }
 822                 p = *in;
 823                 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
 824                                         &p, inlen, -1, 0, 0, ctx);
 825                 if (!ret)
 826                         {
 827                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 828                                         ERR_R_NESTED_ASN1_ERROR);
 829                         return 0;
 830                         }
 831                 if (oclass != V_ASN1_UNIVERSAL)
 832                         utype = V_ASN1_OTHER;
 833                 }
 834         if (tag == -1)
 835                 {
 836                 tag = utype;
 837                 aclass = V_ASN1_UNIVERSAL;
 838                 }
 839         p = *in;
 840         /* Check header */
 841         ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
 842                                 &p, inlen, tag, aclass, opt, ctx);
 843         if (!ret)
 844                 {
 845                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
 846                 return 0;
 847                 }
 848         else if (ret == -1)
 849                 return -1;
 850         ret = 0;
 851         /* SEQUENCE, SET and "OTHER" are left in encoded form */
 852         if ((utype == V_ASN1_SEQUENCE)
 853                 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
 854                 {
 855                 /* Clear context cache for type OTHER because the auto clear
 856                  * when we have a exact match wont work
 857                  */
 858                 if (utype == V_ASN1_OTHER)
 859                         {
 860                         asn1_tlc_clear(ctx);
 861                         }
 862                 /* SEQUENCE and SET must be constructed */
 863                 else if (!cst)
 864                         {
 865                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 866                                 ASN1_R_TYPE_NOT_CONSTRUCTED);
 867                         return 0;
 868                         }
 869
 870                 cont = *in;
 871                 /* If indefinite length constructed find the real end */
 872                 if (inf)
 873                         {
 874                         if (!asn1_find_end(&p, plen, inf))
 875                                  goto err;
 876                         len = p - cont;
 877                         }
 878                 else
 879                         {
 880                         len = p - cont + plen;
 881                         p += plen;
 882                         buf.data = NULL;
 883                         }
 884                 }
 885         else if (cst)
 886                 {
 887                 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
 888                         || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
 889                         || utype == V_ASN1_ENUMERATED)
 890                         {
 891                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 892                                 ASN1_R_TYPE_NOT_PRIMITIVE);
 893                         return 0;
 894                         }
 895                 buf.length = 0;
 896                 buf.max = 0;
 897                 buf.data = NULL;
 898                 /* Should really check the internal tags are correct but
 899                  * some things may get this wrong. The relevant specs
 900                  * say that constructed string types should be OCTET STRINGs
 901                  * internally irrespective of the type. So instead just check
 902                  * for UNIVERSAL class and ignore the tag.
 903                  */
 904                 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
 905                         {
 906                         free_cont = 1;
 907                         goto err;
 908                         }
 909                 len = buf.length;
 910                 /* Append a final null to string */
 911                 if (!BUF_MEM_grow_clean(&buf, len + 1))
 912                         {
 913                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 914                                                 ERR_R_MALLOC_FAILURE);
 915                         return 0;
 916                         }
 917                 buf.data[len] = 0;
 918                 cont = (const unsigned char *)buf.data;
 919                 free_cont = 1;
 920                 }
 921         else
 922                 {
 923                 cont = p;
 924                 len = plen;
 925                 p += plen;
 926                 }
 927
 928         /* We now have content length and type: translate into a structure */
 929         if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
 930                 goto err;
 931
 932         *in = p;
 933         ret = 1;
 934         err:
 935         if (free_cont && buf.data) OPENSSL_free(buf.data);
 936         return ret;
 937         }
 938
 939 /* Translate ASN1 content octets into a structure */
 940
 941 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
 942                         int utype, char *free_cont, const ASN1_ITEM *it)
 943         {
 944         ASN1_VALUE **opval = NULL;
 945         ASN1_STRING *stmp;
 946         ASN1_TYPE *typ = NULL;
 947         int ret = 0;
 948         const ASN1_PRIMITIVE_FUNCS *pf;
 949         ASN1_INTEGER **tint;
 950         pf = it->funcs;
 951
 952         if (pf && pf->prim_c2i)
 953                 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
 954         /* If ANY type clear type and set pointer to internal value */
 955         if (it->utype == V_ASN1_ANY)
 956                 {
 957                 if (!*pval)
 958                         {
 959                         typ = ASN1_TYPE_new();
 960                         if (typ == NULL)
 961                                 goto err;
 962                         *pval = (ASN1_VALUE *)typ;
 963                         }
 964                 else
 965                         typ = (ASN1_TYPE *)*pval;
 966
 967                 if (utype != typ->type)
 968                         ASN1_TYPE_set(typ, utype, NULL);
 969                 opval = pval;
 970                 pval = &typ->value.asn1_value;
 971                 }
 972         switch(utype)
 973                 {
 974                 case V_ASN1_OBJECT:
 975                 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
 976                         goto err;
 977                 break;
 978
 979                 case V_ASN1_NULL:
 980                 if (len)
 981                         {
 982                         ASN1err(ASN1_F_ASN1_EX_C2I,
 983                                                 ASN1_R_NULL_IS_WRONG_LENGTH);
 984                         goto err;
 985                         }
 986                 *pval = (ASN1_VALUE *)1;
 987                 break;
 988
 989                 case V_ASN1_BOOLEAN:
 990                 if (len != 1)
 991                         {
 992                         ASN1err(ASN1_F_ASN1_EX_C2I,
 993                                                 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
 994                         goto err;
 995                         }
 996                 else
 997                         {
 998                         ASN1_BOOLEAN *tbool;
 999                         tbool = (ASN1_BOOLEAN *)pval;
1000                         *tbool = *cont;
1001                         }
1002                 break;
1003
1004                 case V_ASN1_BIT_STRING:
1005                 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
1006                         goto err;
1007                 break;
1008
1009                 case V_ASN1_INTEGER:
1010                 case V_ASN1_NEG_INTEGER:
1011                 case V_ASN1_ENUMERATED:
1012                 case V_ASN1_NEG_ENUMERATED:
1013                 tint = (ASN1_INTEGER **)pval;
1014                 if (!c2i_ASN1_INTEGER(tint, &cont, len))
1015                         goto err;
1016                 /* Fixup type to match the expected form */
1017                 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
1018                 break;
1019
1020                 case V_ASN1_OCTET_STRING:
1021                 case V_ASN1_NUMERICSTRING:
1022                 case V_ASN1_PRINTABLESTRING:
1023                 case V_ASN1_T61STRING:
1024                 case V_ASN1_VIDEOTEXSTRING:
1025                 case V_ASN1_IA5STRING:
1026                 case V_ASN1_UTCTIME:
1027                 case V_ASN1_GENERALIZEDTIME:
1028                 case V_ASN1_GRAPHICSTRING:
1029                 case V_ASN1_VISIBLESTRING:
1030                 case V_ASN1_GENERALSTRING:
1031                 case V_ASN1_UNIVERSALSTRING:
1032                 case V_ASN1_BMPSTRING:
1033                 case V_ASN1_UTF8STRING:
1034                 case V_ASN1_OTHER:
1035                 case V_ASN1_SET:
1036                 case V_ASN1_SEQUENCE:
1037                 default:
1038                 if (utype == V_ASN1_BMPSTRING && (len & 1))
1039                         {
1040                         ASN1err(ASN1_F_ASN1_EX_C2I,
1041                                         ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
1042                         goto err;
1043                         }
1044                 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
1045                         {
1046                         ASN1err(ASN1_F_ASN1_EX_C2I,
1047                                         ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
1048                         goto err;
1049                         }
1050                 /* All based on ASN1_STRING and handled the same */
1051                 if (!*pval)
1052                         {
1053                         stmp = ASN1_STRING_type_new(utype);
1054                         if (!stmp)
1055                                 {
1056                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1057                                                         ERR_R_MALLOC_FAILURE);
1058                                 goto err;
1059                                 }
1060                         *pval = (ASN1_VALUE *)stmp;
1061                         }
1062                 else
1063                         {
1064                         stmp = (ASN1_STRING *)*pval;
1065                         stmp->type = utype;
1066                         }
1067                 /* If we've already allocated a buffer use it */
1068                 if (*free_cont)
1069                         {
1070                         if (stmp->data)
1071                                 OPENSSL_free(stmp->data);
1072                         stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1073                         stmp->length = len;
1074                         *free_cont = 0;
1075                         }
1076                 else
1077                         {
1078                         if (!ASN1_STRING_set(stmp, cont, len))
1079                                 {
1080                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1081                                                         ERR_R_MALLOC_FAILURE);
1082                                 ASN1_STRING_free(stmp);
1083                                 *pval = NULL;
1084                                 goto err;
1085                                 }
1086                         }
1087                 break;
1088                 }
1089         /* If ASN1_ANY and NULL type fix up value */
1090         if (typ && (utype == V_ASN1_NULL))
1091                  typ->value.ptr = NULL;
1092
1093         ret = 1;
1094         err:
1095         if (!ret)
1096                 {
1097                 ASN1_TYPE_free(typ);
1098                 if (opval)
1099                         *opval = NULL;
1100                 }
1101         return ret;
1102         }
1103
1104
1105 /* This function finds the end of an ASN1 structure when passed its maximum
1106  * length, whether it is indefinite length and a pointer to the content.
1107  * This is more efficient than calling asn1_collect because it does not
1108  * recurse on each indefinite length header.
1109  */
1110
1111 static int asn1_find_end(const unsigned char **in, long len, char inf)
1112         {
1113         int expected_eoc;
1114         long plen;
1115         const unsigned char *p = *in, *q;
1116         /* If not indefinite length constructed just add length */
1117         if (inf == 0)
1118                 {
1119                 *in += len;
1120                 return 1;
1121                 }
1122         expected_eoc = 1;
1123         /* Indefinite length constructed form. Find the end when enough EOCs
1124          * are found. If more indefinite length constructed headers
1125          * are encountered increment the expected eoc count otherwise just
1126          * skip to the end of the data.
1127          */
1128         while (len > 0)
1129                 {
1130                 if(asn1_check_eoc(&p, len))
1131                         {
1132                         expected_eoc--;
1133                         if (expected_eoc == 0)
1134                                 break;
1135                         len -= 2;
1136                         continue;
1137                         }
1138                 q = p;
1139                 /* Just read in a header: only care about the length */
1140                 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1141                                 -1, 0, 0, NULL))
1142                         {
1143                         ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1144                         return 0;
1145                         }
1146                 if (inf)
1147                         expected_eoc++;
1148                 else
1149                         p += plen;
1150                 len -= p - q;
1151                 }
1152         if (expected_eoc)
1153                 {
1154                 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1155                 return 0;
1156                 }
1157         *in = p;
1158         return 1;
1159         }
1160 /* This function collects the asn1 data from a constructred string
1161  * type into a buffer. The values of 'in' and 'len' should refer
1162  * to the contents of the constructed type and 'inf' should be set
1163  * if it is indefinite length.
1164  */
1165
1166 #ifndef ASN1_MAX_STRING_NEST
1167 /* This determines how many levels of recursion are permitted in ASN1
1168  * string types. If it is not limited stack overflows can occur. If set
1169  * to zero no recursion is allowed at all. Although zero should be adequate
1170  * examples exist that require a value of 1. So 5 should be more than enough.
1171  */
1172 #define ASN1_MAX_STRING_NEST 5
1173 #endif
1174
1175
1176 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1177                         char inf, int tag, int aclass, int depth)
1178         {
1179         const unsigned char *p, *q;
1180         long plen;
1181         char cst, ininf;
1182         p = *in;
1183         inf &= 1;
1184         /* If no buffer and not indefinite length constructed just pass over
1185          * the encoded data */
1186         if (!buf && !inf)
1187                 {
1188                 *in += len;
1189                 return 1;
1190                 }
1191         while(len > 0)
1192                 {
1193                 q = p;
1194                 /* Check for EOC */
1195                 if (asn1_check_eoc(&p, len))
1196                         {
1197                         /* EOC is illegal outside indefinite length
1198                          * constructed form */
1199                         if (!inf)
1200                                 {
1201                                 ASN1err(ASN1_F_ASN1_COLLECT,
1202                                         ASN1_R_UNEXPECTED_EOC);
1203                                 return 0;
1204                                 }
1205                         inf = 0;
1206                         break;
1207                         }
1208
1209                 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1210                                         len, tag, aclass, 0, NULL))
1211                         {
1212                         ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1213                         return 0;
1214                         }
1215
1216                 /* If indefinite length constructed update max length */
1217                 if (cst)
1218                         {
1219                         if (depth >= ASN1_MAX_STRING_NEST)
1220                                 {
1221                                 ASN1err(ASN1_F_ASN1_COLLECT,
1222                                         ASN1_R_NESTED_ASN1_STRING);
1223                                 return 0;
1224                                 }
1225                         if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
1226                                                 depth + 1))
1227                                 return 0;
1228                         }
1229                 else if (plen && !collect_data(buf, &p, plen))
1230                         return 0;
1231                 len -= p - q;
1232                 }
1233         if (inf)
1234                 {
1235                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1236                 return 0;
1237                 }
1238         *in = p;
1239         return 1;
1240         }
1241
1242 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1243         {
1244         int len;
1245         if (buf)
1246                 {
1247                 len = buf->length;
1248                 if (!BUF_MEM_grow_clean(buf, len + plen))
1249                         {
1250                         ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1251                         return 0;
1252                         }
1253                 memcpy(buf->data + len, *p, plen);
1254                 }
1255         *p += plen;
1256         return 1;
1257         }
1258
1259 /* Check for ASN1 EOC and swallow it if found */
1260
1261 static int asn1_check_eoc(const unsigned char **in, long len)
1262         {
1263         const unsigned char *p;
1264         if (len < 2) return 0;
1265         p = *in;
1266         if (!p[0] && !p[1])
1267                 {
1268                 *in += 2;
1269                 return 1;
1270                 }
1271         return 0;
1272         }
1273
1274 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1275  * but it sets the length for indefinite length constructed
1276  * form, we don't know the exact length but we can set an
1277  * upper bound to the amount of data available minus the
1278  * header length just read.
1279  */
1280
1281 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1282                                 char *inf, char *cst,
1283                                 const unsigned char **in, long len,
1284                                 int exptag, int expclass, char opt,
1285                                 ASN1_TLC *ctx)
1286         {
1287         int i;
1288         int ptag, pclass;
1289         long plen;
1290         const unsigned char *p, *q;
1291         p = *in;
1292         q = p;
1293
1294         if (ctx && ctx->valid)
1295                 {
1296                 i = ctx->ret;
1297                 plen = ctx->plen;
1298                 pclass = ctx->pclass;
1299                 ptag = ctx->ptag;
1300                 p += ctx->hdrlen;
1301                 }
1302         else
1303                 {
1304                 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1305                 if (ctx)
1306                         {
1307                         ctx->ret = i;
1308                         ctx->plen = plen;
1309                         ctx->pclass = pclass;
1310                         ctx->ptag = ptag;
1311                         ctx->hdrlen = p - q;
1312                         ctx->valid = 1;
1313                         /* If definite length, and no error, length +
1314                          * header can't exceed total amount of data available.
1315                          */
1316                         if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1317                                 {
1318                                 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1319                                                         ASN1_R_TOO_LONG);
1320                                 asn1_tlc_clear(ctx);
1321                                 return 0;
1322                                 }
1323                         }
1324                 }
1325
1326         if (i & 0x80)
1327                 {
1328                 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1329                 asn1_tlc_clear(ctx);
1330                 return 0;
1331                 }
1332         if (exptag >= 0)
1333                 {
1334                 if ((exptag != ptag) || (expclass != pclass))
1335                         {
1336                         /* If type is OPTIONAL, not an error:
1337                          * indicate missing type.
1338                          */
1339                         if (opt) return -1;
1340                         asn1_tlc_clear(ctx);
1341                         ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1342                         return 0;
1343                         }
1344                 /* We have a tag and class match:
1345                  * assume we are going to do something with it */
1346                 asn1_tlc_clear(ctx);
1347                 }
1348
1349         if (i & 1)
1350                 plen = len - (p - q);
1351
1352         if (inf)
1353                 *inf = i & 1;
1354
1355         if (cst)
1356                 *cst = i & V_ASN1_CONSTRUCTED;
1357
1358         if (olen)
1359                 *olen = plen;
1360
1361         if (oclass)
1362                 *oclass = pclass;
1363
1364         if (otag)
1365                 *otag = ptag;
1366
1367         *in = p;
1368         return 1;
1369         }