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