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 /* Version to avoid compiler warning about 'c' always non-NULL */
 118 #define asn1_tlc_clear_nc(c)    (c)->valid = 0
 119
 120 /* Decode an ASN1 item, this currently behaves just
 121  * like a standard 'd2i' function. 'in' points to
 122  * a buffer to read the data from, in future we will
 123  * have more advanced versions that can input data
 124  * a piece at a time and this will simply be a special
 125  * case.
 126  */
 127
 128 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
 129                 const unsigned char **in, long len, const ASN1_ITEM *it)
 130 {
 131         ASN1_TLC c;
 132         ASN1_VALUE *ptmpval = NULL;
 133         asn1_tlc_clear_nc(&c);
 134         if (pval && *pval && it->itype == ASN1_ITYPE_PRIMITIVE)
 135                 ptmpval = *pval;
 136         if (ASN1_item_ex_d2i(&ptmpval, in, len, it, -1, 0, 0, &c) > 0) {
 137                 if (pval && it->itype != ASN1_ITYPE_PRIMITIVE) {
 138                         if (*pval)
 139                                 ASN1_item_free(*pval, it);
 140                         *pval = ptmpval;
 141                 }
 142                 return ptmpval;
 143         }
 144         return NULL;
 145 }
 146
 147 int ASN1_template_d2i(ASN1_VALUE **pval,
 148                 const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
 149         {
 150         ASN1_TLC c;
 151         asn1_tlc_clear_nc(&c);
 152         return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
 153         }
 154
 155
 156 /* Decode an item, taking care of IMPLICIT tagging, if any.
 157  * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
 158  */
 159
 160 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
 161                         const ASN1_ITEM *it,
 162                         int tag, int aclass, char opt, ASN1_TLC *ctx)
 163         {
 164         const ASN1_TEMPLATE *tt, *errtt = NULL;
 165         const ASN1_COMPAT_FUNCS *cf;
 166         const ASN1_EXTERN_FUNCS *ef;
 167         const ASN1_AUX *aux = it->funcs;
 168         ASN1_aux_cb *asn1_cb;
 169         const unsigned char *p = NULL, *q;
 170         unsigned char *wp=NULL; /* BIG FAT WARNING!  BREAKS CONST WHERE USED */
 171         unsigned char imphack = 0, oclass;
 172         char seq_eoc, seq_nolen, cst, isopt;
 173         long tmplen;
 174         int i;
 175         int otag;
 176         int ret = 0;
 177         ASN1_VALUE **pchptr, *ptmpval;
 178         if (!pval)
 179                 return 0;
 180         if (aux && aux->asn1_cb)
 181                 asn1_cb = aux->asn1_cb;
 182         else asn1_cb = 0;
 183
 184         switch(it->itype)
 185                 {
 186                 case ASN1_ITYPE_PRIMITIVE:
 187                 if (it->templates)
 188                         {
 189                         /* tagging or OPTIONAL is currently illegal on an item
 190                          * template because the flags can't get passed down.
 191                          * In practice this isn't a problem: we include the
 192                          * relevant flags from the item template in the
 193                          * template itself.
 194                          */
 195                         if ((tag != -1) || opt)
 196                                 {
 197                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 198                                 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
 199                                 goto err;
 200                                 }
 201                         return asn1_template_ex_d2i(pval, in, len,
 202                                         it->templates, opt, ctx);
 203                 }
 204                 return asn1_d2i_ex_primitive(pval, in, len, it,
 205                                                 tag, aclass, opt, ctx);
 206                 break;
 207
 208                 case ASN1_ITYPE_MSTRING:
 209                 p = *in;
 210                 /* Just read in tag and class */
 211                 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
 212                                                 &p, len, -1, 0, 1, ctx);
 213                 if (!ret)
 214                         {
 215                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 216                                         ERR_R_NESTED_ASN1_ERROR);
 217                         goto err;
 218                         }
 219
 220                 /* Must be UNIVERSAL class */
 221                 if (oclass != V_ASN1_UNIVERSAL)
 222                         {
 223                         /* If OPTIONAL, assume this is OK */
 224                         if (opt) return -1;
 225                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 226                                         ASN1_R_MSTRING_NOT_UNIVERSAL);
 227                         goto err;
 228                         }
 229                 /* Check tag matches bit map */
 230                 if (!(ASN1_tag2bit(otag) & it->utype))
 231                         {
 232                         /* If OPTIONAL, assume this is OK */
 233                         if (opt)
 234                                 return -1;
 235                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 236                                         ASN1_R_MSTRING_WRONG_TAG);
 237                         goto err;
 238                         }
 239                 return asn1_d2i_ex_primitive(pval, in, len,
 240                                                 it, otag, 0, 0, ctx);
 241
 242                 case ASN1_ITYPE_EXTERN:
 243                 /* Use new style d2i */
 244                 ef = it->funcs;
 245                 return ef->asn1_ex_d2i(pval, in, len,
 246                                                 it, tag, aclass, opt, ctx);
 247
 248                 case ASN1_ITYPE_COMPAT:
 249                 /* we must resort to old style evil hackery */
 250                 cf = it->funcs;
 251
 252                 /* If OPTIONAL see if it is there */
 253                 if (opt)
 254                         {
 255                         int exptag;
 256                         p = *in;
 257                         if (tag == -1)
 258                                 exptag = it->utype;
 259                         else exptag = tag;
 260                         /* Don't care about anything other than presence
 261                          * of expected tag */
 262
 263                         ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
 264                                         &p, len, exptag, aclass, 1, ctx);
 265                         if (!ret)
 266                                 {
 267                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 268                                         ERR_R_NESTED_ASN1_ERROR);
 269                                 goto err;
 270                                 }
 271                         if (ret == -1)
 272                                 return -1;
 273                         }
 274
 275                 /* This is the old style evil hack IMPLICIT handling:
 276                  * since the underlying code is expecting a tag and
 277                  * class other than the one present we change the
 278                  * buffer temporarily then change it back afterwards.
 279                  * This doesn't and never did work for tags > 30.
 280                  *
 281                  * Yes this is *horrible* but it is only needed for
 282                  * old style d2i which will hopefully not be around
 283                  * for much longer.
 284                  * FIXME: should copy the buffer then modify it so
 285                  * the input buffer can be const: we should *always*
 286                  * copy because the old style d2i might modify the
 287                  * buffer.
 288                  */
 289
 290                 if (tag != -1)
 291                         {
 292                         wp = *(unsigned char **)in;
 293                         imphack = *wp;
 294                         if (p == NULL)
 295                                 {
 296                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 297                                         ERR_R_NESTED_ASN1_ERROR);
 298                                 goto err;
 299                                 }
 300                         *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
 301                                                                 | it->utype);
 302                         }
 303
 304                 ptmpval = cf->asn1_d2i(pval, in, len);
 305
 306                 if (tag != -1)
 307                         *wp = imphack;
 308
 309                 if (ptmpval)
 310                         return 1;
 311
 312                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
 313                 goto err;
 314
 315
 316                 case ASN1_ITYPE_CHOICE:
 317                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
 318                                 goto auxerr;
 319
 320                 if (*pval) {
 321                         /* Free up and zero CHOICE value if initialised */
 322                         i = asn1_get_choice_selector(pval, it);
 323                         if ((i >= 0) && (i < it->tcount)) {
 324                                 tt = it->templates + i;
 325                                 pchptr = asn1_get_field_ptr(pval, tt);
 326                                 ASN1_template_free(pchptr, tt);
 327                                 asn1_set_choice_selector(pval, -1, it);
 328                         }
 329                 } else if (!ASN1_item_ex_new(pval, it)) {
 330                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 331                                                 ERR_R_NESTED_ASN1_ERROR);
 332                         goto err;
 333                 }
 334                 /* CHOICE type, try each possibility in turn */
 335                 p = *in;
 336                 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
 337                         {
 338                         pchptr = asn1_get_field_ptr(pval, tt);
 339                         /* We mark field as OPTIONAL so its absence
 340                          * can be recognised.
 341                          */
 342                         ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
 343                         /* If field not present, try the next one */
 344                         if (ret == -1)
 345                                 continue;
 346                         /* If positive return, read OK, break loop */
 347                         if (ret > 0)
 348                                 break;
 349                         /* Otherwise must be an ASN1 parsing error */
 350                         errtt = tt;
 351                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 352                                                 ERR_R_NESTED_ASN1_ERROR);
 353                         goto err;
 354                         }
 355
 356                 /* Did we fall off the end without reading anything? */
 357                 if (i == it->tcount)
 358                         {
 359                         /* If OPTIONAL, this is OK */
 360                         if (opt)
 361                                 {
 362                                 /* Free and zero it */
 363                                 ASN1_item_ex_free(pval, it);
 364                                 return -1;
 365                                 }
 366                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 367                                         ASN1_R_NO_MATCHING_CHOICE_TYPE);
 368                         goto err;
 369                         }
 370
 371                 asn1_set_choice_selector(pval, i, it);
 372                 *in = p;
 373                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
 374                                 goto auxerr;
 375                 return 1;
 376
 377                 case ASN1_ITYPE_NDEF_SEQUENCE:
 378                 case ASN1_ITYPE_SEQUENCE:
 379                 p = *in;
 380                 tmplen = len;
 381
 382                 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
 383                 if (tag == -1)
 384                         {
 385                         tag = V_ASN1_SEQUENCE;
 386                         aclass = V_ASN1_UNIVERSAL;
 387                         }
 388                 /* Get SEQUENCE length and update len, p */
 389                 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
 390                                         &p, len, tag, aclass, opt, ctx);
 391                 if (!ret)
 392                         {
 393                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 394                                         ERR_R_NESTED_ASN1_ERROR);
 395                         goto err;
 396                         }
 397                 else if (ret == -1)
 398                         return -1;
 399                 if (aux && (aux->flags & ASN1_AFLG_BROKEN))
 400                         {
 401                         len = tmplen - (p - *in);
 402                         seq_nolen = 1;
 403                         }
 404                 /* If indefinite we don't do a length check */
 405                 else seq_nolen = seq_eoc;
 406                 if (!cst)
 407                         {
 408                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 409                                 ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
 410                         goto err;
 411                         }
 412
 413                 if (!*pval && !ASN1_item_ex_new(pval, it))
 414                         {
 415                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 416                                 ERR_R_NESTED_ASN1_ERROR);
 417                         goto err;
 418                         }
 419
 420                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
 421                                 goto auxerr;
 422
 423                 /* Free up and zero any ADB found */
 424                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
 425                         if (tt->flags & ASN1_TFLG_ADB_MASK) {
 426                                 const ASN1_TEMPLATE *seqtt;
 427                                 ASN1_VALUE **pseqval;
 428                                 seqtt = asn1_do_adb(pval, tt, 1);
 429                                 pseqval = asn1_get_field_ptr(pval, seqtt);
 430                                 ASN1_template_free(pseqval, seqtt);
 431                         }
 432                 }
 433
 434                 /* Get each field entry */
 435                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
 436                         {
 437                         const ASN1_TEMPLATE *seqtt;
 438                         ASN1_VALUE **pseqval;
 439                         seqtt = asn1_do_adb(pval, tt, 1);
 440                         if (!seqtt)
 441                                 goto err;
 442                         pseqval = asn1_get_field_ptr(pval, seqtt);
 443                         /* Have we ran out of data? */
 444                         if (!len)
 445                                 break;
 446                         q = p;
 447                         if (asn1_check_eoc(&p, len))
 448                                 {
 449                                 if (!seq_eoc)
 450                                         {
 451                                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 452                                                         ASN1_R_UNEXPECTED_EOC);
 453                                         goto err;
 454                                         }
 455                                 len -= p - q;
 456                                 seq_eoc = 0;
 457                                 q = p;
 458                                 break;
 459                                 }
 460                         /* This determines the OPTIONAL flag value. The field
 461                          * cannot be omitted if it is the last of a SEQUENCE
 462                          * and there is still data to be read. This isn't
 463                          * strictly necessary but it increases efficiency in
 464                          * some cases.
 465                          */
 466                         if (i == (it->tcount - 1))
 467                                 isopt = 0;
 468                         else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
 469                         /* attempt to read in field, allowing each to be
 470                          * OPTIONAL */
 471
 472                         ret = asn1_template_ex_d2i(pseqval, &p, len,
 473                                                         seqtt, isopt, ctx);
 474                         if (!ret)
 475                                 {
 476                                 errtt = seqtt;
 477                                 goto err;
 478                                 }
 479                         else if (ret == -1)
 480                                 {
 481                                 /* OPTIONAL component absent.
 482                                  * Free and zero the field.
 483                                  */
 484                                 ASN1_template_free(pseqval, seqtt);
 485                                 continue;
 486                                 }
 487                         /* Update length */
 488                         len -= p - q;
 489                         }
 490
 491                 /* Check for EOC if expecting one */
 492                 if (seq_eoc && !asn1_check_eoc(&p, len))
 493                         {
 494                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
 495                         goto err;
 496                         }
 497                 /* Check all data read */
 498                 if (!seq_nolen && len)
 499                         {
 500                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 501                                         ASN1_R_SEQUENCE_LENGTH_MISMATCH);
 502                         goto err;
 503                         }
 504
 505                 /* If we get here we've got no more data in the SEQUENCE,
 506                  * however we may not have read all fields so check all
 507                  * remaining are OPTIONAL and clear any that are.
 508                  */
 509                 for (; i < it->tcount; tt++, i++)
 510                         {
 511                         const ASN1_TEMPLATE *seqtt;
 512                         seqtt = asn1_do_adb(pval, tt, 1);
 513                         if (!seqtt)
 514                                 goto err;
 515                         if (seqtt->flags & ASN1_TFLG_OPTIONAL)
 516                                 {
 517                                 ASN1_VALUE **pseqval;
 518                                 pseqval = asn1_get_field_ptr(pval, seqtt);
 519                                 ASN1_template_free(pseqval, seqtt);
 520                                 }
 521                         else
 522                                 {
 523                                 errtt = seqtt;
 524                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 525                                                         ASN1_R_FIELD_MISSING);
 526                                 goto err;
 527                                 }
 528                         }
 529                 /* Save encoding */
 530                 if (!asn1_enc_save(pval, *in, p - *in, it))
 531                         goto auxerr;
 532                 *in = p;
 533                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
 534                                 goto auxerr;
 535                 return 1;
 536
 537                 default:
 538                 return 0;
 539                 }
 540         auxerr:
 541         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
 542         err:
 543         ASN1_item_ex_free(pval, it);
 544         if (errtt)
 545                 ERR_add_error_data(4, "Field=", errtt->field_name,
 546                                         ", Type=", it->sname);
 547         else
 548                 ERR_add_error_data(2, "Type=", it->sname);
 549         return 0;
 550         }
 551
 552 /* Templates are handled with two separate functions.
 553  * One handles any EXPLICIT tag and the other handles the rest.
 554  */
 555
 556 static int asn1_template_ex_d2i(ASN1_VALUE **val,
 557                                 const unsigned char **in, long inlen,
 558                                 const ASN1_TEMPLATE *tt, char opt,
 559                                                         ASN1_TLC *ctx)
 560         {
 561         int flags, aclass;
 562         int ret;
 563         long len;
 564         const unsigned char *p, *q;
 565         char exp_eoc;
 566         if (!val)
 567                 return 0;
 568         flags = tt->flags;
 569         aclass = flags & ASN1_TFLG_TAG_CLASS;
 570
 571         p = *in;
 572
 573         /* Check if EXPLICIT tag expected */
 574         if (flags & ASN1_TFLG_EXPTAG)
 575                 {
 576                 char cst;
 577                 /* Need to work out amount of data available to the inner
 578                  * content and where it starts: so read in EXPLICIT header to
 579                  * get the info.
 580                  */
 581                 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
 582                                         &p, inlen, tt->tag, aclass, opt, ctx);
 583                 q = p;
 584                 if (!ret)
 585                         {
 586                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 587                                         ERR_R_NESTED_ASN1_ERROR);
 588                         return 0;
 589                         }
 590                 else if (ret == -1)
 591                         return -1;
 592                 if (!cst)
 593                         {
 594                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 595                                         ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
 596                         return 0;
 597                         }
 598                 /* We've found the field so it can't be OPTIONAL now */
 599                 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
 600                 if (!ret)
 601                         {
 602                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 603                                         ERR_R_NESTED_ASN1_ERROR);
 604                         return 0;
 605                         }
 606                 /* We read the field in OK so update length */
 607                 len -= p - q;
 608                 if (exp_eoc)
 609                         {
 610                         /* If NDEF we must have an EOC here */
 611                         if (!asn1_check_eoc(&p, len))
 612                                 {
 613                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 614                                                 ASN1_R_MISSING_EOC);
 615                                 goto err;
 616                                 }
 617                         }
 618                 else
 619                         {
 620                         /* Otherwise we must hit the EXPLICIT tag end or its
 621                          * an error */
 622                         if (len)
 623                                 {
 624                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 625                                         ASN1_R_EXPLICIT_LENGTH_MISMATCH);
 626                                 goto err;
 627                                 }
 628                         }
 629                 }
 630                 else
 631                         return asn1_template_noexp_d2i(val, in, inlen,
 632                                                                 tt, opt, ctx);
 633
 634         *in = p;
 635         return 1;
 636
 637         err:
 638         ASN1_template_free(val, tt);
 639         return 0;
 640         }
 641
 642 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
 643                                 const unsigned char **in, long len,
 644                                 const ASN1_TEMPLATE *tt, char opt,
 645                                 ASN1_TLC *ctx)
 646         {
 647         int flags, aclass;
 648         int ret;
 649         const unsigned char *p, *q;
 650         if (!val)
 651                 return 0;
 652         flags = tt->flags;
 653         aclass = flags & ASN1_TFLG_TAG_CLASS;
 654
 655         p = *in;
 656         q = p;
 657
 658         if (flags & ASN1_TFLG_SK_MASK)
 659                 {
 660                 /* SET OF, SEQUENCE OF */
 661                 int sktag, skaclass;
 662                 char sk_eoc;
 663                 /* First work out expected inner tag value */
 664                 if (flags & ASN1_TFLG_IMPTAG)
 665                         {
 666                         sktag = tt->tag;
 667                         skaclass = aclass;
 668                         }
 669                 else
 670                         {
 671                         skaclass = V_ASN1_UNIVERSAL;
 672                         if (flags & ASN1_TFLG_SET_OF)
 673                                 sktag = V_ASN1_SET;
 674                         else
 675                                 sktag = V_ASN1_SEQUENCE;
 676                         }
 677                 /* Get the tag */
 678                 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
 679                                         &p, len, sktag, skaclass, opt, ctx);
 680                 if (!ret)
 681                         {
 682                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 683                                                 ERR_R_NESTED_ASN1_ERROR);
 684                         return 0;
 685                         }
 686                 else if (ret == -1)
 687                         return -1;
 688                 if (!*val)
 689                         *val = (ASN1_VALUE *)sk_new_null();
 690                 else
 691                         {
 692                         /* We've got a valid STACK: free up any items present */
 693                         STACK_OF(ASN1_VALUE) *sktmp
 694                             = (STACK_OF(ASN1_VALUE) *)*val;
 695                         ASN1_VALUE *vtmp;
 696                         while(sk_ASN1_VALUE_num(sktmp) > 0)
 697                                 {
 698                                 vtmp = sk_ASN1_VALUE_pop(sktmp);
 699                                 ASN1_item_ex_free(&vtmp,
 700                                                 ASN1_ITEM_ptr(tt->item));
 701                                 }
 702                         }
 703
 704                 if (!*val)
 705                         {
 706                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 707                                                 ERR_R_MALLOC_FAILURE);
 708                         goto err;
 709                         }
 710
 711                 /* Read as many items as we can */
 712                 while(len > 0)
 713                         {
 714                         ASN1_VALUE *skfield;
 715                         q = p;
 716                         /* See if EOC found */
 717                         if (asn1_check_eoc(&p, len))
 718                                 {
 719                                 if (!sk_eoc)
 720                                         {
 721                                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 722                                                         ASN1_R_UNEXPECTED_EOC);
 723                                         goto err;
 724                                         }
 725                                 len -= p - q;
 726                                 sk_eoc = 0;
 727                                 break;
 728                                 }
 729                         skfield = NULL;
 730                         if (!ASN1_item_ex_d2i(&skfield, &p, len,
 731                                                 ASN1_ITEM_ptr(tt->item),
 732                                                 -1, 0, 0, ctx))
 733                                 {
 734                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 735                                         ERR_R_NESTED_ASN1_ERROR);
 736                                 goto err;
 737                                 }
 738                         len -= p - q;
 739                         if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val,
 740                                                 skfield))
 741                                 {
 742                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 743                                                 ERR_R_MALLOC_FAILURE);
 744                                 goto err;
 745                                 }
 746                         }
 747                 if (sk_eoc)
 748                         {
 749                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
 750                         goto err;
 751                         }
 752                 }
 753         else if (flags & ASN1_TFLG_IMPTAG)
 754                 {
 755                 /* IMPLICIT tagging */
 756                 ret = ASN1_item_ex_d2i(val, &p, len,
 757                         ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
 758                 if (!ret)
 759                         {
 760                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 761                                                 ERR_R_NESTED_ASN1_ERROR);
 762                         goto err;
 763                         }
 764                 else if (ret == -1)
 765                         return -1;
 766                 }
 767         else
 768                 {
 769                 /* Nothing special */
 770                 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
 771                                                         -1, 0, opt, ctx);
 772                 if (!ret)
 773                         {
 774                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
 775                                         ERR_R_NESTED_ASN1_ERROR);
 776                         goto err;
 777                         }
 778                 else if (ret == -1)
 779                         return -1;
 780                 }
 781
 782         *in = p;
 783         return 1;
 784
 785         err:
 786         ASN1_template_free(val, tt);
 787         return 0;
 788         }
 789
 790 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
 791                                 const unsigned char **in, long inlen,
 792                                 const ASN1_ITEM *it,
 793                                 int tag, int aclass, char opt, ASN1_TLC *ctx)
 794         {
 795         int ret = 0, utype;
 796         long plen;
 797         char cst, inf, free_cont = 0;
 798         const unsigned char *p;
 799         BUF_MEM buf;
 800         const unsigned char *cont = NULL;
 801         long len;
 802         if (!pval)
 803                 {
 804                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
 805                 return 0; /* Should never happen */
 806                 }
 807
 808         if (it->itype == ASN1_ITYPE_MSTRING)
 809                 {
 810                 utype = tag;
 811                 tag = -1;
 812                 }
 813         else
 814                 utype = it->utype;
 815
 816         if (utype == V_ASN1_ANY)
 817                 {
 818                 /* If type is ANY need to figure out type from tag */
 819                 unsigned char oclass;
 820                 if (tag >= 0)
 821                         {
 822                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 823                                         ASN1_R_ILLEGAL_TAGGED_ANY);
 824                         return 0;
 825                         }
 826                 if (opt)
 827                         {
 828                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 829                                         ASN1_R_ILLEGAL_OPTIONAL_ANY);
 830                         return 0;
 831                         }
 832                 p = *in;
 833                 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
 834                                         &p, inlen, -1, 0, 0, ctx);
 835                 if (!ret)
 836                         {
 837                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 838                                         ERR_R_NESTED_ASN1_ERROR);
 839                         return 0;
 840                         }
 841                 if (oclass != V_ASN1_UNIVERSAL)
 842                         utype = V_ASN1_OTHER;
 843                 }
 844         if (tag == -1)
 845                 {
 846                 tag = utype;
 847                 aclass = V_ASN1_UNIVERSAL;
 848                 }
 849         p = *in;
 850         /* Check header */
 851         ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
 852                                 &p, inlen, tag, aclass, opt, ctx);
 853         if (!ret)
 854                 {
 855                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
 856                 return 0;
 857                 }
 858         else if (ret == -1)
 859                 return -1;
 860         ret = 0;
 861         /* SEQUENCE, SET and "OTHER" are left in encoded form */
 862         if ((utype == V_ASN1_SEQUENCE)
 863                 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
 864                 {
 865                 /* Clear context cache for type OTHER because the auto clear
 866                  * when we have a exact match wont work
 867                  */
 868                 if (utype == V_ASN1_OTHER)
 869                         {
 870                         asn1_tlc_clear(ctx);
 871                         }
 872                 /* SEQUENCE and SET must be constructed */
 873                 else if (!cst)
 874                         {
 875                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 876                                 ASN1_R_TYPE_NOT_CONSTRUCTED);
 877                         return 0;
 878                         }
 879
 880                 cont = *in;
 881                 /* If indefinite length constructed find the real end */
 882                 if (inf)
 883                         {
 884                         if (!asn1_find_end(&p, plen, inf))
 885                                  goto err;
 886                         len = p - cont;
 887                         }
 888                 else
 889                         {
 890                         len = p - cont + plen;
 891                         p += plen;
 892                         buf.data = NULL;
 893                         }
 894                 }
 895         else if (cst)
 896                 {
 897                 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
 898                         || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
 899                         || utype == V_ASN1_ENUMERATED)
 900                         {
 901                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 902                                 ASN1_R_TYPE_NOT_PRIMITIVE);
 903                         return 0;
 904                         }
 905                 buf.length = 0;
 906                 buf.max = 0;
 907                 buf.data = NULL;
 908                 /* Should really check the internal tags are correct but
 909                  * some things may get this wrong. The relevant specs
 910                  * say that constructed string types should be OCTET STRINGs
 911                  * internally irrespective of the type. So instead just check
 912                  * for UNIVERSAL class and ignore the tag.
 913                  */
 914                 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
 915                         {
 916                         free_cont = 1;
 917                         goto err;
 918                         }
 919                 len = buf.length;
 920                 /* Append a final null to string */
 921                 if (!BUF_MEM_grow_clean(&buf, len + 1))
 922                         {
 923                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 924                                                 ERR_R_MALLOC_FAILURE);
 925                         return 0;
 926                         }
 927                 buf.data[len] = 0;
 928                 cont = (const unsigned char *)buf.data;
 929                 free_cont = 1;
 930                 }
 931         else
 932                 {
 933                 cont = p;
 934                 len = plen;
 935                 p += plen;
 936                 }
 937
 938         /* We now have content length and type: translate into a structure */
 939         if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
 940                 goto err;
 941
 942         *in = p;
 943         ret = 1;
 944         err:
 945         if (free_cont && buf.data) OPENSSL_free(buf.data);
 946         return ret;
 947         }
 948
 949 /* Translate ASN1 content octets into a structure */
 950
 951 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
 952                         int utype, char *free_cont, const ASN1_ITEM *it)
 953         {
 954         ASN1_VALUE **opval = NULL;
 955         ASN1_STRING *stmp;
 956         ASN1_TYPE *typ = NULL;
 957         int ret = 0;
 958         const ASN1_PRIMITIVE_FUNCS *pf;
 959         ASN1_INTEGER **tint;
 960         pf = it->funcs;
 961
 962         if (pf && pf->prim_c2i)
 963                 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
 964         /* If ANY type clear type and set pointer to internal value */
 965         if (it->utype == V_ASN1_ANY)
 966                 {
 967                 if (!*pval)
 968                         {
 969                         typ = ASN1_TYPE_new();
 970                         if (typ == NULL)
 971                                 goto err;
 972                         *pval = (ASN1_VALUE *)typ;
 973                         }
 974                 else
 975                         typ = (ASN1_TYPE *)*pval;
 976
 977                 if (utype != typ->type)
 978                         ASN1_TYPE_set(typ, utype, NULL);
 979                 opval = pval;
 980                 pval = &typ->value.asn1_value;
 981                 }
 982         switch(utype)
 983                 {
 984                 case V_ASN1_OBJECT:
 985                 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
 986                         goto err;
 987                 break;
 988
 989                 case V_ASN1_NULL:
 990                 if (len)
 991                         {
 992                         ASN1err(ASN1_F_ASN1_EX_C2I,
 993                                                 ASN1_R_NULL_IS_WRONG_LENGTH);
 994                         goto err;
 995                         }
 996                 *pval = (ASN1_VALUE *)1;
 997                 break;
 998
 999                 case V_ASN1_BOOLEAN:
1000                 if (len != 1)
1001                         {
1002                         ASN1err(ASN1_F_ASN1_EX_C2I,
1003                                                 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
1004                         goto err;
1005                         }
1006                 else
1007                         {
1008                         ASN1_BOOLEAN *tbool;
1009                         tbool = (ASN1_BOOLEAN *)pval;
1010                         *tbool = *cont;
1011                         }
1012                 break;
1013
1014                 case V_ASN1_BIT_STRING:
1015                 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
1016                         goto err;
1017                 break;
1018
1019                 case V_ASN1_INTEGER:
1020                 case V_ASN1_NEG_INTEGER:
1021                 case V_ASN1_ENUMERATED:
1022                 case V_ASN1_NEG_ENUMERATED:
1023                 tint = (ASN1_INTEGER **)pval;
1024                 if (!c2i_ASN1_INTEGER(tint, &cont, len))
1025                         goto err;
1026                 /* Fixup type to match the expected form */
1027                 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
1028                 break;
1029
1030                 case V_ASN1_OCTET_STRING:
1031                 case V_ASN1_NUMERICSTRING:
1032                 case V_ASN1_PRINTABLESTRING:
1033                 case V_ASN1_T61STRING:
1034                 case V_ASN1_VIDEOTEXSTRING:
1035                 case V_ASN1_IA5STRING:
1036                 case V_ASN1_UTCTIME:
1037                 case V_ASN1_GENERALIZEDTIME:
1038                 case V_ASN1_GRAPHICSTRING:
1039                 case V_ASN1_VISIBLESTRING:
1040                 case V_ASN1_GENERALSTRING:
1041                 case V_ASN1_UNIVERSALSTRING:
1042                 case V_ASN1_BMPSTRING:
1043                 case V_ASN1_UTF8STRING:
1044                 case V_ASN1_OTHER:
1045                 case V_ASN1_SET:
1046                 case V_ASN1_SEQUENCE:
1047                 default:
1048                 if (utype == V_ASN1_BMPSTRING && (len & 1))
1049                         {
1050                         ASN1err(ASN1_F_ASN1_EX_C2I,
1051                                         ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
1052                         goto err;
1053                         }
1054                 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
1055                         {
1056                         ASN1err(ASN1_F_ASN1_EX_C2I,
1057                                         ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
1058                         goto err;
1059                         }
1060                 /* All based on ASN1_STRING and handled the same */
1061                 if (!*pval)
1062                         {
1063                         stmp = ASN1_STRING_type_new(utype);
1064                         if (!stmp)
1065                                 {
1066                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1067                                                         ERR_R_MALLOC_FAILURE);
1068                                 goto err;
1069                                 }
1070                         *pval = (ASN1_VALUE *)stmp;
1071                         }
1072                 else
1073                         {
1074                         stmp = (ASN1_STRING *)*pval;
1075                         stmp->type = utype;
1076                         }
1077                 /* If we've already allocated a buffer use it */
1078                 if (*free_cont)
1079                         {
1080                         if (stmp->data)
1081                                 OPENSSL_free(stmp->data);
1082                         stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1083                         stmp->length = len;
1084                         *free_cont = 0;
1085                         }
1086                 else
1087                         {
1088                         if (!ASN1_STRING_set(stmp, cont, len))
1089                                 {
1090                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1091                                                         ERR_R_MALLOC_FAILURE);
1092                                 ASN1_STRING_free(stmp);
1093                                 *pval = NULL;
1094                                 goto err;
1095                                 }
1096                         }
1097                 break;
1098                 }
1099         /* If ASN1_ANY and NULL type fix up value */
1100         if (typ && (utype == V_ASN1_NULL))
1101                  typ->value.ptr = NULL;
1102
1103         ret = 1;
1104         err:
1105         if (!ret)
1106                 {
1107                 ASN1_TYPE_free(typ);
1108                 if (opval)
1109                         *opval = NULL;
1110                 }
1111         return ret;
1112         }
1113
1114
1115 /* This function finds the end of an ASN1 structure when passed its maximum
1116  * length, whether it is indefinite length and a pointer to the content.
1117  * This is more efficient than calling asn1_collect because it does not
1118  * recurse on each indefinite length header.
1119  */
1120
1121 static int asn1_find_end(const unsigned char **in, long len, char inf)
1122         {
1123         int expected_eoc;
1124         long plen;
1125         const unsigned char *p = *in, *q;
1126         /* If not indefinite length constructed just add length */
1127         if (inf == 0)
1128                 {
1129                 *in += len;
1130                 return 1;
1131                 }
1132         expected_eoc = 1;
1133         /* Indefinite length constructed form. Find the end when enough EOCs
1134          * are found. If more indefinite length constructed headers
1135          * are encountered increment the expected eoc count otherwise just
1136          * skip to the end of the data.
1137          */
1138         while (len > 0)
1139                 {
1140                 if(asn1_check_eoc(&p, len))
1141                         {
1142                         expected_eoc--;
1143                         if (expected_eoc == 0)
1144                                 break;
1145                         len -= 2;
1146                         continue;
1147                         }
1148                 q = p;
1149                 /* Just read in a header: only care about the length */
1150                 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1151                                 -1, 0, 0, NULL))
1152                         {
1153                         ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1154                         return 0;
1155                         }
1156                 if (inf)
1157                         expected_eoc++;
1158                 else
1159                         p += plen;
1160                 len -= p - q;
1161                 }
1162         if (expected_eoc)
1163                 {
1164                 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1165                 return 0;
1166                 }
1167         *in = p;
1168         return 1;
1169         }
1170 /* This function collects the asn1 data from a constructred string
1171  * type into a buffer. The values of 'in' and 'len' should refer
1172  * to the contents of the constructed type and 'inf' should be set
1173  * if it is indefinite length.
1174  */
1175
1176 #ifndef ASN1_MAX_STRING_NEST
1177 /* This determines how many levels of recursion are permitted in ASN1
1178  * string types. If it is not limited stack overflows can occur. If set
1179  * to zero no recursion is allowed at all. Although zero should be adequate
1180  * examples exist that require a value of 1. So 5 should be more than enough.
1181  */
1182 #define ASN1_MAX_STRING_NEST 5
1183 #endif
1184
1185
1186 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1187                         char inf, int tag, int aclass, int depth)
1188         {
1189         const unsigned char *p, *q;
1190         long plen;
1191         char cst, ininf;
1192         p = *in;
1193         inf &= 1;
1194         /* If no buffer and not indefinite length constructed just pass over
1195          * the encoded data */
1196         if (!buf && !inf)
1197                 {
1198                 *in += len;
1199                 return 1;
1200                 }
1201         while(len > 0)
1202                 {
1203                 q = p;
1204                 /* Check for EOC */
1205                 if (asn1_check_eoc(&p, len))
1206                         {
1207                         /* EOC is illegal outside indefinite length
1208                          * constructed form */
1209                         if (!inf)
1210                                 {
1211                                 ASN1err(ASN1_F_ASN1_COLLECT,
1212                                         ASN1_R_UNEXPECTED_EOC);
1213                                 return 0;
1214                                 }
1215                         inf = 0;
1216                         break;
1217                         }
1218
1219                 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1220                                         len, tag, aclass, 0, NULL))
1221                         {
1222                         ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1223                         return 0;
1224                         }
1225
1226                 /* If indefinite length constructed update max length */
1227                 if (cst)
1228                         {
1229                         if (depth >= ASN1_MAX_STRING_NEST)
1230                                 {
1231                                 ASN1err(ASN1_F_ASN1_COLLECT,
1232                                         ASN1_R_NESTED_ASN1_STRING);
1233                                 return 0;
1234                                 }
1235                         if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
1236                                                 depth + 1))
1237                                 return 0;
1238                         }
1239                 else if (plen && !collect_data(buf, &p, plen))
1240                         return 0;
1241                 len -= p - q;
1242                 }
1243         if (inf)
1244                 {
1245                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1246                 return 0;
1247                 }
1248         *in = p;
1249         return 1;
1250         }
1251
1252 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1253         {
1254         int len;
1255         if (buf)
1256                 {
1257                 len = buf->length;
1258                 if (!BUF_MEM_grow_clean(buf, len + plen))
1259                         {
1260                         ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1261                         return 0;
1262                         }
1263                 memcpy(buf->data + len, *p, plen);
1264                 }
1265         *p += plen;
1266         return 1;
1267         }
1268
1269 /* Check for ASN1 EOC and swallow it if found */
1270
1271 static int asn1_check_eoc(const unsigned char **in, long len)
1272         {
1273         const unsigned char *p;
1274         if (len < 2) return 0;
1275         p = *in;
1276         if (!p[0] && !p[1])
1277                 {
1278                 *in += 2;
1279                 return 1;
1280                 }
1281         return 0;
1282         }
1283
1284 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1285  * but it sets the length for indefinite length constructed
1286  * form, we don't know the exact length but we can set an
1287  * upper bound to the amount of data available minus the
1288  * header length just read.
1289  */
1290
1291 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1292                                 char *inf, char *cst,
1293                                 const unsigned char **in, long len,
1294                                 int exptag, int expclass, char opt,
1295                                 ASN1_TLC *ctx)
1296         {
1297         int i;
1298         int ptag, pclass;
1299         long plen;
1300         const unsigned char *p, *q;
1301         p = *in;
1302         q = p;
1303
1304         if (ctx && ctx->valid)
1305                 {
1306                 i = ctx->ret;
1307                 plen = ctx->plen;
1308                 pclass = ctx->pclass;
1309                 ptag = ctx->ptag;
1310                 p += ctx->hdrlen;
1311                 }
1312         else
1313                 {
1314                 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1315                 if (ctx)
1316                         {
1317                         ctx->ret = i;
1318                         ctx->plen = plen;
1319                         ctx->pclass = pclass;
1320                         ctx->ptag = ptag;
1321                         ctx->hdrlen = p - q;
1322                         ctx->valid = 1;
1323                         /* If definite length, and no error, length +
1324                          * header can't exceed total amount of data available.
1325                          */
1326                         if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1327                                 {
1328                                 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1329                                                         ASN1_R_TOO_LONG);
1330                                 asn1_tlc_clear(ctx);
1331                                 return 0;
1332                                 }
1333                         }
1334                 }
1335
1336         if (i & 0x80)
1337                 {
1338                 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1339                 asn1_tlc_clear(ctx);
1340                 return 0;
1341                 }
1342         if (exptag >= 0)
1343                 {
1344                 if ((exptag != ptag) || (expclass != pclass))
1345                         {
1346                         /* If type is OPTIONAL, not an error:
1347                          * indicate missing type.
1348                          */
1349                         if (opt) return -1;
1350                         asn1_tlc_clear(ctx);
1351                         ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1352                         return 0;
1353                         }
1354                 /* We have a tag and class match:
1355                  * assume we are going to do something with it */
1356                 asn1_tlc_clear(ctx);
1357                 }
1358
1359         if (i & 1)
1360                 plen = len - (p - q);
1361
1362         if (inf)
1363                 *inf = i & 1;
1364
1365         if (cst)
1366                 *cst = i & V_ASN1_CONSTRUCTED;
1367
1368         if (olen)
1369                 *olen = plen;
1370
1371         if (oclass)
1372                 *oclass = pclass;
1373
1374         if (otag)
1375                 *otag = ptag;
1376
1377         *in = p;
1378         return 1;
1379         }