crypto/asn1/tasn_dec.c

   1 /* tasn_dec.c */
   2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL
   3  * project 2000.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 2000-2004 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
  70 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
  71                                 char inf, int tag, int aclass);
  72
  73 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
  74
  75 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
  76                                 char *inf, char *cst,
  77                                 const unsigned char **in, long len,
  78                                 int exptag, int expclass, char opt,
  79                                 ASN1_TLC *ctx);
  80
  81 static int asn1_template_ex_d2i(ASN1_VALUE **pval,
  82                                 const unsigned char **in, long len,
  83                                 const ASN1_TEMPLATE *tt, char opt,
  84                                 ASN1_TLC *ctx);
  85 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
  86                                 const unsigned char **in, long len,
  87                                 const ASN1_TEMPLATE *tt, char opt,
  88                                 ASN1_TLC *ctx);
  89 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
  90                                 const unsigned char **in, long len,
  91                                 const ASN1_ITEM *it,
  92                                 int tag, int aclass, char opt, ASN1_TLC *ctx);
  93
  94 /* Table to convert tags to bit values, used for MSTRING type */
  95 static unsigned long tag2bit[32] = {
  96 0,      0,      0,      B_ASN1_BIT_STRING,      /* tags  0 -  3 */
  97 B_ASN1_OCTET_STRING,    0,      0,              B_ASN1_UNKNOWN,/* tags  4- 7 */
  98 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags  8-11 */
  99 B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
 100 0,      0,      B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING,   /* tags 16-19 */
 101 B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
 102 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,                        /* tags 23-24 */
 103 B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
 104 B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
 105         };
 106
 107 unsigned long ASN1_tag2bit(int tag)
 108         {
 109         if ((tag < 0) || (tag > 30)) return 0;
 110         return tag2bit[tag];
 111         }
 112
 113 /* Macro to initialize and invalidate the cache */
 114
 115 #define asn1_tlc_clear(c)       if (c) (c)->valid = 0
 116
 117 /* Decode an ASN1 item, this currently behaves just
 118  * like a standard 'd2i' function. 'in' points to
 119  * a buffer to read the data from, in future we will
 120  * have more advanced versions that can input data
 121  * a piece at a time and this will simply be a special
 122  * case.
 123  */
 124
 125 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
 126                 const unsigned char **in, long len, const ASN1_ITEM *it)
 127         {
 128         ASN1_TLC c;
 129         ASN1_VALUE *ptmpval = NULL;
 130         if (!pval)
 131                 pval = &ptmpval;
 132         asn1_tlc_clear(&c);
 133         if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
 134                 return *pval;
 135         return NULL;
 136         }
 137
 138 int ASN1_template_d2i(ASN1_VALUE **pval,
 139                 const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
 140         {
 141         ASN1_TLC c;
 142         asn1_tlc_clear(&c);
 143         return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
 144         }
 145
 146
 147 /* Decode an item, taking care of IMPLICIT tagging, if any.
 148  * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
 149  */
 150
 151 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
 152                         const ASN1_ITEM *it,
 153                         int tag, int aclass, char opt, ASN1_TLC *ctx)
 154         {
 155         const ASN1_TEMPLATE *tt, *errtt = NULL;
 156         const ASN1_COMPAT_FUNCS *cf;
 157         const ASN1_EXTERN_FUNCS *ef;
 158         const ASN1_AUX *aux = it->funcs;
 159         ASN1_aux_cb *asn1_cb;
 160         const unsigned char *p, *q;
 161         unsigned char *wp=NULL; /* BIG FAT WARNING!  BREAKS CONST WHERE USED */
 162         unsigned char imphack = 0, oclass;
 163         char seq_eoc, seq_nolen, cst, isopt;
 164         long tmplen;
 165         int i;
 166         int otag;
 167         int ret = 0;
 168         ASN1_VALUE *pchval, **pchptr, *ptmpval;
 169         if (!pval)
 170                 return 0;
 171         if (aux && aux->asn1_cb)
 172                 asn1_cb = aux->asn1_cb;
 173         else asn1_cb = 0;
 174
 175         switch(it->itype)
 176                 {
 177                 case ASN1_ITYPE_PRIMITIVE:
 178                 if (it->templates)
 179                         {
 180                         /* tagging or OPTIONAL is currently illegal on an item
 181                          * template because the flags can't get passed down.
 182                          * In practice this isn't a problem: we include the
 183                          * relevant flags from the item template in the
 184                          * template itself.
 185                          */
 186                         if ((tag != -1) || opt)
 187                                 {
 188                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 189                                 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
 190                                 goto err;
 191                                 }
 192                         return asn1_template_ex_d2i(pval, in, len,
 193                                         it->templates, opt, ctx);
 194                 }
 195                 return asn1_d2i_ex_primitive(pval, in, len, it,
 196                                                 tag, aclass, opt, ctx);
 197                 break;
 198
 199                 case ASN1_ITYPE_MSTRING:
 200                 p = *in;
 201                 /* Just read in tag and class */
 202                 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
 203                                                 &p, len, -1, 0, 1, ctx);
 204                 if (!ret)
 205                         {
 206                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 207                                         ERR_R_NESTED_ASN1_ERROR);
 208                         goto err;
 209                         }
 210
 211                 /* Must be UNIVERSAL class */
 212                 if (oclass != V_ASN1_UNIVERSAL)
 213                         {
 214                         /* If OPTIONAL, assume this is OK */
 215                         if (opt) return -1;
 216                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 217                                         ASN1_R_MSTRING_NOT_UNIVERSAL);
 218                         goto err;
 219                         }
 220                 /* Check tag matches bit map */
 221                 if (!(ASN1_tag2bit(otag) & it->utype))
 222                         {
 223                         /* If OPTIONAL, assume this is OK */
 224                         if (opt)
 225                                 return -1;
 226                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 227                                         ASN1_R_MSTRING_WRONG_TAG);
 228                         goto err;
 229                         }
 230                 return asn1_d2i_ex_primitive(pval, in, len,
 231                                                 it, otag, 0, 0, ctx);
 232
 233                 case ASN1_ITYPE_EXTERN:
 234                 /* Use new style d2i */
 235                 ef = it->funcs;
 236                 return ef->asn1_ex_d2i(pval, in, len,
 237                                                 it, tag, aclass, opt, ctx);
 238
 239                 case ASN1_ITYPE_COMPAT:
 240                 /* we must resort to old style evil hackery */
 241                 cf = it->funcs;
 242
 243                 /* If OPTIONAL see if it is there */
 244                 if (opt)
 245                         {
 246                         int exptag;
 247                         p = *in;
 248                         if (tag == -1)
 249                                 exptag = it->utype;
 250                         else exptag = tag;
 251                         /* Don't care about anything other than presence
 252                          * of expected tag */
 253
 254                         ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
 255                                         &p, len, exptag, aclass, 1, ctx);
 256                         if (!ret)
 257                                 {
 258                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 259                                         ERR_R_NESTED_ASN1_ERROR);
 260                                 goto err;
 261                                 }
 262                         if (ret == -1)
 263                                 return -1;
 264                         }
 265
 266                 /* This is the old style evil hack IMPLICIT handling:
 267                  * since the underlying code is expecting a tag and
 268                  * class other than the one present we change the
 269                  * buffer temporarily then change it back afterwards.
 270                  * This doesn't and never did work for tags > 30.
 271                  *
 272                  * Yes this is *horrible* but it is only needed for
 273                  * old style d2i which will hopefully not be around
 274                  * for much longer.
 275                  * FIXME: should copy the buffer then modify it so
 276                  * the input buffer can be const: we should *always*
 277                  * copy because the old style d2i might modify the
 278                  * buffer.
 279                  */
 280
 281                 if (tag != -1)
 282                         {
 283                         wp = *(unsigned char **)in;
 284                         imphack = *wp;
 285                         *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
 286                                                                 | it->utype);
 287                         }
 288
 289                 ptmpval = cf->asn1_d2i(pval, in, len);
 290
 291                 if (tag != -1)
 292                         *wp = imphack;
 293
 294                 if (ptmpval)
 295                         return 1;
 296
 297                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
 298                 goto err;
 299
 300
 301                 case ASN1_ITYPE_CHOICE:
 302                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
 303                                 goto auxerr;
 304
 305                 /* Allocate structure */
 306                 if (!*pval && !ASN1_item_ex_new(pval, it))
 307                         {
 308                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 309                                                 ERR_R_NESTED_ASN1_ERROR);
 310                         goto err;
 311                         }
 312                 /* CHOICE type, try each possibility in turn */
 313                 pchval = NULL;
 314                 p = *in;
 315                 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
 316                         {
 317                         pchptr = asn1_get_field_ptr(pval, tt);
 318                         /* We mark field as OPTIONAL so its absence
 319                          * can be recognised.
 320                          */
 321                         ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
 322                         /* If field not present, try the next one */
 323                         if (ret == -1)
 324                                 continue;
 325                         /* If positive return, read OK, break loop */
 326                         if (ret > 0)
 327                                 break;
 328                         /* Otherwise must be an ASN1 parsing error */
 329                         errtt = tt;
 330                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 331                                                 ERR_R_NESTED_ASN1_ERROR);
 332                         goto err;
 333                         }
 334
 335                 /* Did we fall off the end without reading anything? */
 336                 if (i == it->tcount)
 337                         {
 338                         /* If OPTIONAL, this is OK */
 339                         if (opt)
 340                                 {
 341                                 /* Free and zero it */
 342                                 ASN1_item_ex_free(pval, it);
 343                                 return -1;
 344                                 }
 345                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 346                                         ASN1_R_NO_MATCHING_CHOICE_TYPE);
 347                         goto err;
 348                         }
 349
 350                 asn1_set_choice_selector(pval, i, it);
 351                 *in = p;
 352                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
 353                                 goto auxerr;
 354                 return 1;
 355
 356                 case ASN1_ITYPE_NDEF_SEQUENCE:
 357                 case ASN1_ITYPE_SEQUENCE:
 358                 p = *in;
 359                 tmplen = len;
 360
 361                 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
 362                 if (tag == -1)
 363                         {
 364                         tag = V_ASN1_SEQUENCE;
 365                         aclass = V_ASN1_UNIVERSAL;
 366                         }
 367                 /* Get SEQUENCE length and update len, p */
 368                 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
 369                                         &p, len, tag, aclass, opt, ctx);
 370                 if (!ret)
 371                         {
 372                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 373                                         ERR_R_NESTED_ASN1_ERROR);
 374                         goto err;
 375                         }
 376                 else if (ret == -1)
 377                         return -1;
 378                 if (aux && (aux->flags & ASN1_AFLG_BROKEN))
 379                         {
 380                         len = tmplen - (p - *in);
 381                         seq_nolen = 1;
 382                         }
 383                 /* If indefinite we don't do a length check */
 384                 else seq_nolen = seq_eoc;
 385                 if (!cst)
 386                         {
 387                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 388                                 ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
 389                         goto err;
 390                         }
 391
 392                 if (!*pval && !!ASN1_item_ex_new(pval, it))
 393                         {
 394                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 395                                 ERR_R_NESTED_ASN1_ERROR);
 396                         goto err;
 397                         }
 398
 399                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
 400                                 goto auxerr;
 401
 402                 /* Get each field entry */
 403                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
 404                         {
 405                         const ASN1_TEMPLATE *seqtt;
 406                         ASN1_VALUE **pseqval;
 407                         seqtt = asn1_do_adb(pval, tt, 1);
 408                         if (!seqtt)
 409                                 goto err;
 410                         pseqval = asn1_get_field_ptr(pval, seqtt);
 411                         /* Have we ran out of data? */
 412                         if (!len)
 413                                 break;
 414                         q = p;
 415                         if (asn1_check_eoc(&p, len))
 416                                 {
 417                                 if (!seq_eoc)
 418                                         {
 419                                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 420                                                         ASN1_R_UNEXPECTED_EOC);
 421                                         goto err;
 422                                         }
 423                                 len -= p - q;
 424                                 seq_eoc = 0;
 425                                 q = p;
 426                                 break;
 427                                 }
 428                         /* This determines the OPTIONAL flag value. The field
 429                          * cannot be omitted if it is the last of a SEQUENCE
 430                          * and there is still data to be read. This isn't
 431                          * strictly necessary but it increases efficiency in
 432                          * some cases.
 433                          */
 434                         if (i == (it->tcount - 1))
 435                                 isopt = 0;
 436                         else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
 437                         /* attempt to read in field, allowing each to be
 438                          * OPTIONAL */
 439
 440                         ret = asn1_template_ex_d2i(pseqval, &p, len,
 441                                                         seqtt, isopt, ctx);
 442                         if (!ret)
 443                                 {
 444                                 errtt = seqtt;
 445                                 goto err;
 446                                 }
 447                         else if (ret == -1)
 448                                 {
 449                                 /* OPTIONAL component absent.
 450                                  * Free and zero the field.
 451                                  */
 452                                 ASN1_template_free(pseqval, seqtt);
 453                                 continue;
 454                                 }
 455                         /* Update length */
 456                         len -= p - q;
 457                         }
 458
 459                 /* Check for EOC if expecting one */
 460                 if (seq_eoc && !asn1_check_eoc(&p, len))
 461                         {
 462                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
 463                         goto err;
 464                         }
 465                 /* Check all data read */
 466                 if (!seq_nolen && len)
 467                         {
 468                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 469                                         ASN1_R_SEQUENCE_LENGTH_MISMATCH);
 470                         goto err;
 471                         }
 472
 473                 /* If we get here we've got no more data in the SEQUENCE,
 474                  * however we may not have read all fields so check all
 475                  * remaining are OPTIONAL and clear any that are.
 476                  */
 477                 for (; i < it->tcount; tt++, i++)
 478                         {
 479                         const ASN1_TEMPLATE *seqtt;
 480                         seqtt = asn1_do_adb(pval, tt, 1);
 481                         if (!seqtt)
 482                                 goto err;
 483                         if (seqtt->flags & ASN1_TFLG_OPTIONAL)
 484                                 {
 485                                 ASN1_VALUE **pseqval;
 486                                 pseqval = asn1_get_field_ptr(pval, seqtt);
 487                                 ASN1_template_free(pseqval, seqtt);
 488                                 }
 489                         else
 490                                 {
 491                                 errtt = seqtt;
 492                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
 493                                                         ASN1_R_FIELD_MISSING);
 494                                 goto err;
 495                                 }
 496                         }
 497                 /* Save encoding */
 498                 if (!asn1_enc_save(pval, *in, p - *in, it))
 499                         goto auxerr;
 500                 *in = p;
 501                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
 502                                 goto auxerr;
 503                 return 1;
 504
 505                 default:
 506                 return 0;
 507                 }
 508         auxerr:
 509         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
 510         err:
 511         ASN1_item_ex_free(pval, it);
 512         if (errtt)
 513                 ERR_add_error_data(4, "Field=", errtt->field_name,
 514                                         ", Type=", it->sname);
 515         else
 516                 ERR_add_error_data(2, "Type=", it->sname);
 517         return 0;
 518         }
 519
 520 /* Templates are handled with two separate functions.
 521  * One handles any EXPLICIT tag and the other handles the rest.
 522  */
 523
 524 static int asn1_template_ex_d2i(ASN1_VALUE **val,
 525                                 const unsigned char **in, long inlen,
 526                                 const ASN1_TEMPLATE *tt, char opt,
 527                                                         ASN1_TLC *ctx)
 528         {
 529         int flags, aclass;
 530         int ret;
 531         long len;
 532         const unsigned char *p, *q;
 533         char exp_eoc;
 534         if (!val)
 535                 return 0;
 536         flags = tt->flags;
 537         aclass = flags & ASN1_TFLG_TAG_CLASS;
 538
 539         p = *in;
 540
 541         /* Check if EXPLICIT tag expected */
 542         if (flags & ASN1_TFLG_EXPTAG)
 543                 {
 544                 char cst;
 545                 /* Need to work out amount of data available to the inner
 546                  * content and where it starts: so read in EXPLICIT header to
 547                  * get the info.
 548                  */
 549                 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
 550                                         &p, inlen, tt->tag, aclass, opt, ctx);
 551                 q = p;
 552                 if (!ret)
 553                         {
 554                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 555                                         ERR_R_NESTED_ASN1_ERROR);
 556                         return 0;
 557                         }
 558                 else if (ret == -1)
 559                         return -1;
 560                 if (!cst)
 561                         {
 562                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 563                                         ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
 564                         return 0;
 565                         }
 566                 /* We've found the field so it can't be OPTIONAL now */
 567                 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
 568                 if (!ret)
 569                         {
 570                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 571                                         ERR_R_NESTED_ASN1_ERROR);
 572                         return 0;
 573                         }
 574                 /* We read the field in OK so update length */
 575                 len -= p - q;
 576                 if (exp_eoc)
 577                         {
 578                         /* If NDEF we must have an EOC here */
 579                         if (!asn1_check_eoc(&p, len))
 580                                 {
 581                                 ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 582                                                 ASN1_R_MISSING_EOC);
 583                                 goto err;
 584                                 }
 585                         }
 586                 else
 587                         {
 588                         /* Otherwise we must hit the EXPLICIT tag end or its
 589                          * an error */
 590                         if (len)
 591                                 {
 592                                 ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 593                                         ASN1_R_EXPLICIT_LENGTH_MISMATCH);
 594                                 goto err;
 595                                 }
 596                         }
 597                 }
 598                 else
 599                         return asn1_template_noexp_d2i(val, in, inlen,
 600                                                                 tt, opt, ctx);
 601
 602         *in = p;
 603         return 1;
 604
 605         err:
 606         ASN1_template_free(val, tt);
 607         *val = NULL;
 608         return 0;
 609         }
 610
 611 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
 612                                 const unsigned char **in, long len,
 613                                 const ASN1_TEMPLATE *tt, char opt,
 614                                 ASN1_TLC *ctx)
 615         {
 616         int flags, aclass;
 617         int ret;
 618         const unsigned char *p, *q;
 619         if (!val)
 620                 return 0;
 621         flags = tt->flags;
 622         aclass = flags & ASN1_TFLG_TAG_CLASS;
 623
 624         p = *in;
 625         q = p;
 626
 627         if (flags & ASN1_TFLG_SK_MASK)
 628                 {
 629                 /* SET OF, SEQUENCE OF */
 630                 int sktag, skaclass;
 631                 char sk_eoc;
 632                 /* First work out expected inner tag value */
 633                 if (flags & ASN1_TFLG_IMPTAG)
 634                         {
 635                         sktag = tt->tag;
 636                         skaclass = aclass;
 637                         }
 638                 else
 639                         {
 640                         skaclass = V_ASN1_UNIVERSAL;
 641                         if (flags & ASN1_TFLG_SET_OF)
 642                                 sktag = V_ASN1_SET;
 643                         else
 644                                 sktag = V_ASN1_SEQUENCE;
 645                         }
 646                 /* Get the tag */
 647                 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
 648                                         &p, len, sktag, skaclass, opt, ctx);
 649                 if (!ret)
 650                         {
 651                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 652                                                 ERR_R_NESTED_ASN1_ERROR);
 653                         return 0;
 654                         }
 655                 else if (ret == -1)
 656                         return -1;
 657                 if (!*val)
 658                         *val = (ASN1_VALUE *)sk_new_null();
 659                 else
 660                         {
 661                         /* We've got a valid STACK: free up any items present */
 662                         STACK *sktmp = (STACK *)*val;
 663                         ASN1_VALUE *vtmp;
 664                         while(sk_num(sktmp) > 0)
 665                                 {
 666                                 vtmp = (ASN1_VALUE *)sk_pop(sktmp);
 667                                 ASN1_item_ex_free(&vtmp,
 668                                                 ASN1_ITEM_ptr(tt->item));
 669                                 }
 670                         }
 671
 672                 if (!*val)
 673                         {
 674                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
 675                                                 ERR_R_MALLOC_FAILURE);
 676                         goto err;
 677                         }
 678
 679                 /* Read as many items as we can */
 680                 while(len > 0)
 681                         {
 682                         ASN1_VALUE *skfield;
 683                         q = p;
 684                         /* See if EOC found */
 685                         if (asn1_check_eoc(&p, len))
 686                                 {
 687                                 if (!sk_eoc)
 688                                         {
 689                                         ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 690                                                         ASN1_R_UNEXPECTED_EOC);
 691                                         goto err;
 692                                         }
 693                                 len -= p - q;
 694                                 sk_eoc = 0;
 695                                 break;
 696                                 }
 697                         skfield = NULL;
 698                         if (!ASN1_item_ex_d2i(&skfield, &p, len,
 699                                                 ASN1_ITEM_ptr(tt->item),
 700                                                 -1, 0, 0, ctx))
 701                                 {
 702                                 ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 703                                         ERR_R_NESTED_ASN1_ERROR);
 704                                 goto err;
 705                                 }
 706                         len -= p - q;
 707                         if (!sk_push((STACK *)*val, (char *)skfield))
 708                                 {
 709                                 ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 710                                                 ERR_R_MALLOC_FAILURE);
 711                                 goto err;
 712                                 }
 713                         }
 714                 if (sk_eoc)
 715                         {
 716                         ASN1err(ASN1_F_ASN1_TEMPLATE_D2I, ASN1_R_MISSING_EOC);
 717                         goto err;
 718                         }
 719                 }
 720         else if (flags & ASN1_TFLG_IMPTAG)
 721                 {
 722                 /* IMPLICIT tagging */
 723                 ret = ASN1_item_ex_d2i(val, &p, len,
 724                         ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
 725                 if (!ret)
 726                         {
 727                         ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 728                                                 ERR_R_NESTED_ASN1_ERROR);
 729                         goto err;
 730                         }
 731                 else if (ret == -1)
 732                         return -1;
 733                 }
 734         else
 735                 {
 736                 /* Nothing special */
 737                 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
 738                                                         -1, 0, opt, ctx);
 739                 if (!ret)
 740                         {
 741                         ASN1err(ASN1_F_ASN1_TEMPLATE_D2I,
 742                                         ERR_R_NESTED_ASN1_ERROR);
 743                         goto err;
 744                         }
 745                 else if (ret == -1)
 746                         return -1;
 747                 }
 748
 749         *in = p;
 750         return 1;
 751
 752         err:
 753         ASN1_template_free(val, tt);
 754         *val = NULL;
 755         return 0;
 756         }
 757
 758 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
 759                                 const unsigned char **in, long inlen,
 760                                 const ASN1_ITEM *it,
 761                                 int tag, int aclass, char opt, ASN1_TLC *ctx)
 762         {
 763         int ret = 0, utype;
 764         long plen;
 765         char cst, inf, free_cont = 0;
 766         const unsigned char *p;
 767         BUF_MEM buf;
 768         const unsigned char *cont = NULL;
 769         long len;
 770         if (!pval)
 771                 {
 772                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
 773                 return 0; /* Should never happen */
 774                 }
 775
 776         if (it->itype == ASN1_ITYPE_MSTRING)
 777                 {
 778                 utype = tag;
 779                 tag = -1;
 780                 }
 781         else
 782                 utype = it->utype;
 783
 784         if (utype == V_ASN1_ANY)
 785                 {
 786                 /* If type is ANY need to figure out type from tag */
 787                 unsigned char oclass;
 788                 if (tag >= 0)
 789                         {
 790                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 791                                         ASN1_R_ILLEGAL_TAGGED_ANY);
 792                         return 0;
 793                         }
 794                 if (opt)
 795                         {
 796                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 797                                         ASN1_R_ILLEGAL_OPTIONAL_ANY);
 798                         return 0;
 799                         }
 800                 p = *in;
 801                 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
 802                                         &p, inlen, -1, 0, 0, ctx);
 803                 if (!ret)
 804                         {
 805                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 806                                         ERR_R_NESTED_ASN1_ERROR);
 807                         return 0;
 808                         }
 809                 if (oclass != V_ASN1_UNIVERSAL)
 810                         utype = V_ASN1_OTHER;
 811                 }
 812         if (tag == -1)
 813                 {
 814                 tag = utype;
 815                 aclass = V_ASN1_UNIVERSAL;
 816                 }
 817         p = *in;
 818         /* Check header */
 819         ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
 820                                 &p, inlen, tag, aclass, opt, ctx);
 821         if (!ret)
 822                 {
 823                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
 824                 return 0;
 825                 }
 826         else if (ret == -1)
 827                 return -1;
 828         /* SEQUENCE, SET and "OTHER" are left in encoded form */
 829         if ((utype == V_ASN1_SEQUENCE)
 830                 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
 831                 {
 832                 /* Clear context cache for type OTHER because the auto clear
 833                  * when we have a exact match wont work
 834                  */
 835                 if (utype == V_ASN1_OTHER)
 836                         {
 837                         asn1_tlc_clear(ctx);
 838                         }
 839                 /* SEQUENCE and SET must be constructed */
 840                 else if (!cst)
 841                         {
 842                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 843                                 ASN1_R_TYPE_NOT_CONSTRUCTED);
 844                         return 0;
 845                         }
 846
 847                 cont = *in;
 848                 /* If indefinite length constructed find the real end */
 849                 if (inf)
 850                         {
 851                         if (!asn1_collect(NULL, &p, plen, inf, -1, -1))
 852                                  goto err;
 853                         len = p - cont;
 854                         }
 855                 else
 856                         {
 857                         len = p - cont + plen;
 858                         p += plen;
 859                         buf.data = NULL;
 860                         }
 861                 }
 862         else if (cst)
 863                 {
 864                 buf.length = 0;
 865                 buf.max = 0;
 866                 buf.data = NULL;
 867                 /* Should really check the internal tags are correct but
 868                  * some things may get this wrong. The relevant specs
 869                  * say that constructed string types should be OCTET STRINGs
 870                  * internally irrespective of the type. So instead just check
 871                  * for UNIVERSAL class and ignore the tag.
 872                  */
 873                 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL))
 874                         goto err;
 875                 len = buf.length;
 876                 /* Append a final null to string */
 877                 if (!BUF_MEM_grow_clean(&buf, len + 1))
 878                         {
 879                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 880                                                 ERR_R_MALLOC_FAILURE);
 881                         return 0;
 882                         }
 883                 buf.data[len] = 0;
 884                 cont = (const unsigned char *)buf.data;
 885                 free_cont = 1;
 886                 }
 887         else
 888                 {
 889                 cont = p;
 890                 len = plen;
 891                 p += plen;
 892                 }
 893
 894         /* We now have content length and type: translate into a structure */
 895         if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
 896                 goto err;
 897
 898         *in = p;
 899         ret = 1;
 900         err:
 901         if (free_cont && buf.data) OPENSSL_free(buf.data);
 902         return ret;
 903         }
 904
 905 /* Translate ASN1 content octets into a structure */
 906
 907 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
 908                         int utype, char *free_cont, const ASN1_ITEM *it)
 909         {
 910         ASN1_VALUE **opval = NULL;
 911         ASN1_STRING *stmp;
 912         ASN1_TYPE *typ = NULL;
 913         int ret = 0;
 914         const ASN1_PRIMITIVE_FUNCS *pf;
 915         ASN1_INTEGER **tint;
 916         pf = it->funcs;
 917
 918         if (pf && pf->prim_c2i)
 919                 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
 920         /* If ANY type clear type and set pointer to internal value */
 921         if (it->utype == V_ASN1_ANY)
 922                 {
 923                 if (!*pval)
 924                         {
 925                         typ = ASN1_TYPE_new();
 926                         *pval = (ASN1_VALUE *)typ;
 927                         }
 928                 else
 929                         typ = (ASN1_TYPE *)*pval;
 930
 931                 if (utype != typ->type)
 932                         ASN1_TYPE_set(typ, utype, NULL);
 933                 opval = pval;
 934                 pval = (ASN1_VALUE **)&typ->value.ptr;
 935                 }
 936         switch(utype)
 937                 {
 938                 case V_ASN1_OBJECT:
 939                 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
 940                         goto err;
 941                 break;
 942
 943                 case V_ASN1_NULL:
 944                 if (len)
 945                         {
 946                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 947                                                 ASN1_R_NULL_IS_WRONG_LENGTH);
 948                         goto err;
 949                         }
 950                 *pval = (ASN1_VALUE *)1;
 951                 break;
 952
 953                 case V_ASN1_BOOLEAN:
 954                 if (len != 1)
 955                         {
 956                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
 957                                                 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
 958                         goto err;
 959                         }
 960                 else
 961                         {
 962                         ASN1_BOOLEAN *tbool;
 963                         tbool = (ASN1_BOOLEAN *)pval;
 964                         *tbool = *cont;
 965                         }
 966                 break;
 967
 968                 case V_ASN1_BIT_STRING:
 969                 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
 970                         goto err;
 971                 break;
 972
 973                 case V_ASN1_INTEGER:
 974                 case V_ASN1_NEG_INTEGER:
 975                 case V_ASN1_ENUMERATED:
 976                 case V_ASN1_NEG_ENUMERATED:
 977                 tint = (ASN1_INTEGER **)pval;
 978                 if (!c2i_ASN1_INTEGER(tint, &cont, len))
 979                         goto err;
 980                 /* Fixup type to match the expected form */
 981                 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
 982                 break;
 983
 984                 case V_ASN1_OCTET_STRING:
 985                 case V_ASN1_NUMERICSTRING:
 986                 case V_ASN1_PRINTABLESTRING:
 987                 case V_ASN1_T61STRING:
 988                 case V_ASN1_VIDEOTEXSTRING:
 989                 case V_ASN1_IA5STRING:
 990                 case V_ASN1_UTCTIME:
 991                 case V_ASN1_GENERALIZEDTIME:
 992                 case V_ASN1_GRAPHICSTRING:
 993                 case V_ASN1_VISIBLESTRING:
 994                 case V_ASN1_GENERALSTRING:
 995                 case V_ASN1_UNIVERSALSTRING:
 996                 case V_ASN1_BMPSTRING:
 997                 case V_ASN1_UTF8STRING:
 998                 case V_ASN1_OTHER:
 999                 case V_ASN1_SET:
1000                 case V_ASN1_SEQUENCE:
1001                 default:
1002                 /* All based on ASN1_STRING and handled the same */
1003                 if (!*pval)
1004                         {
1005                         stmp = ASN1_STRING_type_new(utype);
1006                         if (!stmp)
1007                                 {
1008                                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
1009                                                         ERR_R_MALLOC_FAILURE);
1010                                 goto err;
1011                                 }
1012                         *pval = (ASN1_VALUE *)stmp;
1013                         }
1014                 else
1015                         {
1016                         stmp = (ASN1_STRING *)*pval;
1017                         stmp->type = utype;
1018                         }
1019                 /* If we've already allocated a buffer use it */
1020                 if (*free_cont)
1021                         {
1022                         if (stmp->data)
1023                                 OPENSSL_free(stmp->data);
1024                         stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1025                         stmp->length = len;
1026                         *free_cont = 0;
1027                         }
1028                 else
1029                         {
1030                         if (!ASN1_STRING_set(stmp, cont, len))
1031                                 {
1032                                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
1033                                                         ERR_R_MALLOC_FAILURE);
1034                                 ASN1_STRING_free(stmp);
1035                                 *pval = NULL;
1036                                 goto err;
1037                                 }
1038                         }
1039                 break;
1040                 }
1041         /* If ASN1_ANY and NULL type fix up value */
1042         if (typ && (utype == V_ASN1_NULL))
1043                  typ->value.ptr = NULL;
1044
1045         ret = 1;
1046         err:
1047         if (!ret)
1048                 {
1049                 ASN1_TYPE_free(typ);
1050                 if (opval)
1051                         *opval = NULL;
1052                 }
1053         return ret;
1054         }
1055
1056 /* This function collects the asn1 data from a constructred string
1057  * type into a buffer. The values of 'in' and 'len' should refer
1058  * to the contents of the constructed type and 'inf' should be set
1059  * if it is indefinite length. If 'buf' is NULL then we just want
1060  * to find the end of the current structure: useful for indefinite
1061  * length constructed stuff.
1062  */
1063
1064 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1065                                 char inf, int tag, int aclass)
1066         {
1067         const unsigned char *p, *q;
1068         long plen;
1069         char cst, ininf;
1070         p = *in;
1071         inf &= 1;
1072         /* If no buffer and not indefinite length constructed just pass over
1073          * the encoded data */
1074         if (!buf && !inf)
1075                 {
1076                 *in += len;
1077                 return 1;
1078                 }
1079         while(len > 0)
1080                 {
1081                 q = p;
1082                 /* Check for EOC */
1083                 if (asn1_check_eoc(&p, len))
1084                         {
1085                         /* EOC is illegal outside indefinite length
1086                          * constructed form */
1087                         if (!inf)
1088                                 {
1089                                 ASN1err(ASN1_F_ASN1_COLLECT,
1090                                         ASN1_R_UNEXPECTED_EOC);
1091                                 return 0;
1092                                 }
1093                         inf = 0;
1094                         break;
1095                         }
1096
1097                 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1098                                         len, tag, aclass, 0, NULL))
1099                         {
1100                         ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1101                         return 0;
1102                         }
1103
1104                 /* If indefinite length constructed update max length */
1105                 if (cst)
1106                         {
1107                         if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
1108                                 return 0;
1109                         }
1110                 else if (!collect_data(buf, &p, plen))
1111                         return 0;
1112                 len -= p - q;
1113                 }
1114         if (inf)
1115                 {
1116                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1117                 return 0;
1118                 }
1119         *in = p;
1120         return 1;
1121         }
1122
1123 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1124         {
1125         int len;
1126         if (buf)
1127                 {
1128                 len = buf->length;
1129                 if (!BUF_MEM_grow_clean(buf, len + plen))
1130                         {
1131                         ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1132                         return 0;
1133                         }
1134                 memcpy(buf->data + len, *p, plen);
1135                 }
1136         *p += plen;
1137         return 1;
1138         }
1139
1140 /* Check for ASN1 EOC and swallow it if found */
1141
1142 static int asn1_check_eoc(const unsigned char **in, long len)
1143         {
1144         const unsigned char *p;
1145         if (len < 2) return 0;
1146         p = *in;
1147         if (!p[0] && !p[1])
1148                 {
1149                 *in += 2;
1150                 return 1;
1151                 }
1152         return 0;
1153         }
1154
1155 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1156  * but it sets the length for indefinite length constructed
1157  * form, we don't know the exact length but we can set an
1158  * upper bound to the amount of data available minus the
1159  * header length just read.
1160  */
1161
1162 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1163                                 char *inf, char *cst,
1164                                 const unsigned char **in, long len,
1165                                 int exptag, int expclass, char opt,
1166                                 ASN1_TLC *ctx)
1167         {
1168         int i;
1169         int ptag, pclass;
1170         long plen;
1171         const unsigned char *p, *q;
1172         p = *in;
1173         q = p;
1174
1175         if (ctx && ctx->valid)
1176                 {
1177                 i = ctx->ret;
1178                 plen = ctx->plen;
1179                 pclass = ctx->pclass;
1180                 ptag = ctx->ptag;
1181                 p += ctx->hdrlen;
1182                 }
1183         else
1184                 {
1185                 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1186                 if (ctx)
1187                         {
1188                         ctx->ret = i;
1189                         ctx->plen = plen;
1190                         ctx->pclass = pclass;
1191                         ctx->ptag = ptag;
1192                         ctx->hdrlen = p - q;
1193                         ctx->valid = 1;
1194                         /* If definite length, and no error, length +
1195                          * header can't exceed total amount of data available.
1196                          */
1197                         if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1198                                 {
1199                                 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1200                                                         ASN1_R_TOO_LONG);
1201                                 asn1_tlc_clear(ctx);
1202                                 return 0;
1203                                 }
1204                         }
1205                 }
1206
1207         if (i & 0x80)
1208                 {
1209                 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1210                 asn1_tlc_clear(ctx);
1211                 return 0;
1212                 }
1213         if (exptag >= 0)
1214                 {
1215                 if ((exptag != ptag) || (expclass != pclass))
1216                         {
1217                         /* If type is OPTIONAL, not an error:
1218                          * indicate missing type.
1219                          */
1220                         if (opt) return -1;
1221                         asn1_tlc_clear(ctx);
1222                         ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1223                         return 0;
1224                         }
1225                 /* We have a tag and class match:
1226                  * assume we are going to do something with it */
1227                 asn1_tlc_clear(ctx);
1228                 }
1229
1230         if (i & 1)
1231                 plen = len - (p - q);
1232
1233         if (inf)
1234                 *inf = i & 1;
1235
1236         if (cst)
1237                 *cst = i & V_ASN1_CONSTRUCTED;
1238
1239         if (olen)
1240                 *olen = plen;
1241
1242         if (oclass)
1243                 *oclass = pclass;
1244
1245         if (otag)
1246                 *otag = ptag;
1247
1248         *in = p;
1249         return 1;
1250         }