lib/decoding.c

   1 /*
   2  * Copyright (C) 2002-2014 Free Software Foundation, Inc.
   3  *
   4  * This file is part of LIBTASN1.
   5  *
   6  * The LIBTASN1 library is free software; you can redistribute it
   7  * and/or modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19  * 02110-1301, USA
  20  */
  21
  22
  23 /*****************************************************/
  24 /* File: decoding.c                                  */
  25 /* Description: Functions to manage DER decoding     */
  26 /*****************************************************/
  27
  28 #include <int.h>
  29 #include <parser_aux.h>
  30 #include <gstr.h>
  31 #include <structure.h>
  32 #include <element.h>
  33 #include <limits.h>
  34 #include <intprops.h>
  35
  36 #ifdef DEBUG
  37 # define warn() fprintf(stderr, "%s: %d\n", __func__, __LINE__)
  38 #else
  39 # define warn()
  40 #endif
  41
  42 #define HAVE_TWO(x) (x>=2?1:0)
  43
  44 #define DECR_LEN(l, s) do { \
  45           l -= s; \
  46           if (l < 0) { \
  47             warn(); \
  48             result = ASN1_DER_ERROR; \
  49             goto cleanup; \
  50           } \
  51         } while (0)
  52
  53 static int
  54 _asn1_get_indefinite_length_string (const unsigned char *der, int der_len, int *len);
  55
  56 static void
  57 _asn1_error_description_tag_error (asn1_node node, char *ErrorDescription)
  58 {
  59
  60   Estrcpy (ErrorDescription, ":: tag error near element '");
  61   _asn1_hierarchical_name (node, ErrorDescription + strlen (ErrorDescription),
  62                            ASN1_MAX_ERROR_DESCRIPTION_SIZE - 40);
  63   Estrcat (ErrorDescription, "'");
  64
  65 }
  66
  67 /**
  68  * asn1_get_length_der:
  69  * @der: DER data to decode.
  70  * @der_len: Length of DER data to decode.
  71  * @len: Output variable containing the length of the DER length field.
  72  *
  73  * Extract a length field from DER data.
  74  *
  75  * Returns: Return the decoded length value, or -1 on indefinite
  76  *   length, or -2 when the value was too big to fit in a int, or -4
  77  *   when the decoded length value plus @len would exceed @der_len.
  78  **/
  79 long
  80 asn1_get_length_der (const unsigned char *der, int der_len, int *len)
  81 {
  82   unsigned int ans;
  83   int k, punt, sum;
  84
  85   *len = 0;
  86   if (der_len <= 0)
  87     return 0;
  88
  89   if (!(der[0] & 128))
  90     {
  91       /* short form */
  92       *len = 1;
  93       ans = der[0];
  94     }
  95   else
  96     {
  97       /* Long form */
  98       k = der[0] & 0x7F;
  99       punt = 1;
 100       if (k)
 101         {                       /* definite length method */
 102           ans = 0;
 103           while (punt <= k && punt < der_len)
 104             {
 105               if (INT_MULTIPLY_OVERFLOW (ans, 256))
 106                 return -2;
 107               ans *= 256;
 108
 109               if (INT_ADD_OVERFLOW (ans, ((unsigned) der[punt])))
 110                 return -2;
 111               ans += der[punt];
 112               punt++;
 113             }
 114         }
 115       else
 116         {                       /* indefinite length method */
 117           *len = punt;
 118           return -1;
 119         }
 120
 121       *len = punt;
 122     }
 123
 124   sum = ans;
 125   if (ans >= INT_MAX || INT_ADD_OVERFLOW (sum, (*len)))
 126     return -2;
 127   sum += *len;
 128
 129   if (sum > der_len)
 130     return -4;
 131
 132   return ans;
 133 }
 134
 135 /**
 136  * asn1_get_tag_der:
 137  * @der: DER data to decode.
 138  * @der_len: Length of DER data to decode.
 139  * @cls: Output variable containing decoded class.
 140  * @len: Output variable containing the length of the DER TAG data.
 141  * @tag: Output variable containing the decoded tag.
 142  *
 143  * Decode the class and TAG from DER code.
 144  *
 145  * Returns: Returns %ASN1_SUCCESS on success, or an error.
 146  **/
 147 int
 148 asn1_get_tag_der (const unsigned char *der, int der_len,
 149                   unsigned char *cls, int *len, unsigned long *tag)
 150 {
 151   unsigned int ris;
 152   int punt;
 153
 154   if (der == NULL || der_len < 2 || len == NULL)
 155     return ASN1_DER_ERROR;
 156
 157   *cls = der[0] & 0xE0;
 158   if ((der[0] & 0x1F) != 0x1F)
 159     {
 160       /* short form */
 161       *len = 1;
 162       ris = der[0] & 0x1F;
 163     }
 164   else
 165     {
 166       /* Long form */
 167       punt = 1;
 168       ris = 0;
 169       while (punt < der_len && der[punt] & 128)
 170         {
 171
 172           if (INT_MULTIPLY_OVERFLOW (ris, 128))
 173             return ASN1_DER_ERROR;
 174           ris *= 128;
 175
 176           if (INT_ADD_OVERFLOW (ris, ((unsigned) (der[punt] & 0x7F))))
 177             return ASN1_DER_ERROR;
 178           ris += (der[punt] & 0x7F);
 179           punt++;
 180         }
 181
 182       if (punt >= der_len)
 183         return ASN1_DER_ERROR;
 184
 185       if (INT_MULTIPLY_OVERFLOW (ris, 128))
 186         return ASN1_DER_ERROR;
 187       ris *= 128;
 188
 189       if (INT_ADD_OVERFLOW (ris, ((unsigned) (der[punt] & 0x7F))))
 190         return ASN1_DER_ERROR;
 191       ris += (der[punt] & 0x7F);
 192       punt++;
 193
 194       *len = punt;
 195     }
 196
 197   if (tag)
 198     *tag = ris;
 199   return ASN1_SUCCESS;
 200 }
 201
 202 /**
 203  * asn1_get_length_ber:
 204  * @ber: BER data to decode.
 205  * @ber_len: Length of BER data to decode.
 206  * @len: Output variable containing the length of the BER length field.
 207  *
 208  * Extract a length field from BER data.  The difference to
 209  * asn1_get_length_der() is that this function will return a length
 210  * even if the value has indefinite encoding.
 211  *
 212  * Returns: Return the decoded length value, or negative value when
 213  *   the value was too big.
 214  *
 215  * Since: 2.0
 216  **/
 217 long
 218 asn1_get_length_ber (const unsigned char *ber, int ber_len, int *len)
 219 {
 220   int ret;
 221   long err;
 222
 223   ret = asn1_get_length_der (ber, ber_len, len);
 224   if (ret == -1)
 225     {                           /* indefinite length method */
 226       err = _asn1_get_indefinite_length_string (ber + 1, ber_len, &ret);
 227       if (err != ASN1_SUCCESS)
 228         return -3;
 229     }
 230
 231   return ret;
 232 }
 233
 234 /**
 235  * asn1_get_octet_der:
 236  * @der: DER data to decode containing the OCTET SEQUENCE.
 237  * @der_len: Length of DER data to decode.
 238  * @ret_len: Output variable containing the length of the DER data.
 239  * @str: Pre-allocated output buffer to put decoded OCTET SEQUENCE in.
 240  * @str_size: Length of pre-allocated output buffer.
 241  * @str_len: Output variable containing the length of the OCTET SEQUENCE.
 242  *
 243  * Extract an OCTET SEQUENCE from DER data.
 244  *
 245  * Returns: Returns %ASN1_SUCCESS on success, or an error.
 246  **/
 247 int
 248 asn1_get_octet_der (const unsigned char *der, int der_len,
 249                     int *ret_len, unsigned char *str, int str_size,
 250                     int *str_len)
 251 {
 252   int len_len = 0;
 253
 254   if (der_len <= 0)
 255     return ASN1_GENERIC_ERROR;
 256
 257   *str_len = asn1_get_length_der (der, der_len, &len_len);
 258
 259   if (*str_len < 0)
 260     return ASN1_DER_ERROR;
 261
 262   *ret_len = *str_len + len_len;
 263   if (str_size >= *str_len)
 264     {
 265       if (*str_len > 0 && str != NULL)
 266         memcpy (str, der + len_len, *str_len);
 267     }
 268   else
 269     {
 270       return ASN1_MEM_ERROR;
 271     }
 272
 273   return ASN1_SUCCESS;
 274 }
 275
 276 /* Returns ASN1_SUCCESS on success or an error code on error.
 277  */
 278 static int
 279 _asn1_get_time_der (const unsigned char *der, int der_len, int *ret_len,
 280                     char *str, int str_size)
 281 {
 282   int len_len, str_len;
 283
 284   if (der_len <= 0 || str == NULL)
 285     return ASN1_DER_ERROR;
 286
 287   str_len = asn1_get_length_der (der, der_len, &len_len);
 288   if (str_len <= 0 || str_size < str_len)
 289     return ASN1_DER_ERROR;
 290
 291   memcpy (str, der + len_len, str_len);
 292   str[str_len] = 0;
 293   *ret_len = str_len + len_len;
 294
 295   return ASN1_SUCCESS;
 296 }
 297
 298 static int
 299 _asn1_get_objectid_der (const unsigned char *der, int der_len, int *ret_len,
 300                         char *str, int str_size)
 301 {
 302   int len_len, len, k;
 303   int leading;
 304   char temp[LTOSTR_MAX_SIZE];
 305   unsigned long val, val1;
 306
 307   *ret_len = 0;
 308   if (str && str_size > 0)
 309     str[0] = 0;                 /* no oid */
 310
 311   if (str == NULL || der_len <= 0)
 312     return ASN1_GENERIC_ERROR;
 313
 314   len = asn1_get_length_der (der, der_len, &len_len);
 315
 316   if (len <= 0 || len + len_len > der_len)
 317     return ASN1_DER_ERROR;
 318
 319   val1 = der[len_len] / 40;
 320   val = der[len_len] - val1 * 40;
 321
 322   _asn1_str_cpy (str, str_size, _asn1_ltostr (val1, temp));
 323   _asn1_str_cat (str, str_size, ".");
 324   _asn1_str_cat (str, str_size, _asn1_ltostr (val, temp));
 325
 326   val = 0;
 327   leading = 1;
 328   for (k = 1; k < len; k++)
 329     {
 330       /* X.690 mandates that the leading byte must never be 0x80
 331        */
 332       if (leading != 0 && der[len_len + k] == 0x80)
 333         return ASN1_DER_ERROR;
 334       leading = 0;
 335
 336       /* check for wrap around */
 337       if (INT_LEFT_SHIFT_OVERFLOW (val, 7))
 338         return ASN1_DER_ERROR;
 339
 340       val = val << 7;
 341       val |= der[len_len + k] & 0x7F;
 342
 343       if (!(der[len_len + k] & 0x80))
 344         {
 345           _asn1_str_cat (str, str_size, ".");
 346           _asn1_str_cat (str, str_size, _asn1_ltostr (val, temp));
 347           val = 0;
 348           leading = 1;
 349         }
 350     }
 351
 352   if (INT_ADD_OVERFLOW (len, len_len))
 353     return ASN1_DER_ERROR;
 354
 355   *ret_len = len + len_len;
 356
 357   return ASN1_SUCCESS;
 358 }
 359
 360 /**
 361  * asn1_get_bit_der:
 362  * @der: DER data to decode containing the BIT SEQUENCE.
 363  * @der_len: Length of DER data to decode.
 364  * @ret_len: Output variable containing the length of the DER data.
 365  * @str: Pre-allocated output buffer to put decoded BIT SEQUENCE in.
 366  * @str_size: Length of pre-allocated output buffer.
 367  * @bit_len: Output variable containing the size of the BIT SEQUENCE.
 368  *
 369  * Extract a BIT SEQUENCE from DER data.
 370  *
 371  * Returns: Return %ASN1_SUCCESS on success, or an error.
 372  **/
 373 int
 374 asn1_get_bit_der (const unsigned char *der, int der_len,
 375                   int *ret_len, unsigned char *str, int str_size,
 376                   int *bit_len)
 377 {
 378   int len_len = 0, len_byte;
 379
 380   if (der_len <= 0)
 381     return ASN1_GENERIC_ERROR;
 382
 383   len_byte = asn1_get_length_der (der, der_len, &len_len) - 1;
 384   if (len_byte < 0)
 385     return ASN1_DER_ERROR;
 386
 387   *ret_len = len_byte + len_len + 1;
 388   *bit_len = len_byte * 8 - der[len_len];
 389
 390   if (*bit_len < 0)
 391     return ASN1_DER_ERROR;
 392
 393   if (str_size >= len_byte)
 394     {
 395       if (len_byte > 0 && str)
 396         memcpy (str, der + len_len + 1, len_byte);
 397     }
 398   else
 399     {
 400       return ASN1_MEM_ERROR;
 401     }
 402
 403   return ASN1_SUCCESS;
 404 }
 405
 406
 407 static int
 408 _asn1_extract_tag_der (asn1_node node, const unsigned char *der, int der_len,
 409                        int *ret_len)
 410 {
 411   asn1_node p;
 412   int counter, len2, len3, is_tag_implicit;
 413   int result;
 414   unsigned long tag, tag_implicit = 0;
 415   unsigned char class, class2, class_implicit = 0;
 416
 417   if (der_len <= 0)
 418     return ASN1_GENERIC_ERROR;
 419
 420   counter = is_tag_implicit = 0;
 421
 422   if (node->type & CONST_TAG)
 423     {
 424       p = node->down;
 425       while (p)
 426         {
 427           if (type_field (p->type) == ASN1_ETYPE_TAG)
 428             {
 429               if (p->type & CONST_APPLICATION)
 430                 class2 = ASN1_CLASS_APPLICATION;
 431               else if (p->type & CONST_UNIVERSAL)
 432                 class2 = ASN1_CLASS_UNIVERSAL;
 433               else if (p->type & CONST_PRIVATE)
 434                 class2 = ASN1_CLASS_PRIVATE;
 435               else
 436                 class2 = ASN1_CLASS_CONTEXT_SPECIFIC;
 437
 438               if (p->type & CONST_EXPLICIT)
 439                 {
 440                   if (asn1_get_tag_der
 441                       (der + counter, der_len, &class, &len2,
 442                        &tag) != ASN1_SUCCESS)
 443                     return ASN1_DER_ERROR;
 444
 445                   DECR_LEN(der_len, len2);
 446                   counter += len2;
 447
 448                   len3 =
 449                     asn1_get_length_ber (der + counter, der_len,
 450                                          &len2);
 451                   if (len3 < 0)
 452                     return ASN1_DER_ERROR;
 453
 454                   DECR_LEN(der_len, len2);
 455                   counter += len2;
 456
 457                   if (!is_tag_implicit)
 458                     {
 459                       if ((class != (class2 | ASN1_CLASS_STRUCTURED)) ||
 460                           (tag != strtoul ((char *) p->value, NULL, 10)))
 461                         return ASN1_TAG_ERROR;
 462                     }
 463                   else
 464                     {           /* ASN1_TAG_IMPLICIT */
 465                       if ((class != class_implicit) || (tag != tag_implicit))
 466                         return ASN1_TAG_ERROR;
 467                     }
 468                   is_tag_implicit = 0;
 469                 }
 470               else
 471                 {               /* ASN1_TAG_IMPLICIT */
 472                   if (!is_tag_implicit)
 473                     {
 474                       if ((type_field (node->type) == ASN1_ETYPE_SEQUENCE) ||
 475                           (type_field (node->type) == ASN1_ETYPE_SEQUENCE_OF)
 476                           || (type_field (node->type) == ASN1_ETYPE_SET)
 477                           || (type_field (node->type) == ASN1_ETYPE_SET_OF))
 478                         class2 |= ASN1_CLASS_STRUCTURED;
 479                       class_implicit = class2;
 480                       tag_implicit = strtoul ((char *) p->value, NULL, 10);
 481                       is_tag_implicit = 1;
 482                     }
 483                 }
 484             }
 485           p = p->right;
 486         }
 487     }
 488
 489   if (is_tag_implicit)
 490     {
 491       if (asn1_get_tag_der
 492           (der + counter, der_len, &class, &len2,
 493            &tag) != ASN1_SUCCESS)
 494         return ASN1_DER_ERROR;
 495
 496       DECR_LEN(der_len, len2);
 497
 498       if ((class != class_implicit) || (tag != tag_implicit))
 499         {
 500           if (type_field (node->type) == ASN1_ETYPE_OCTET_STRING)
 501             {
 502               class_implicit |= ASN1_CLASS_STRUCTURED;
 503               if ((class != class_implicit) || (tag != tag_implicit))
 504                 return ASN1_TAG_ERROR;
 505             }
 506           else
 507             return ASN1_TAG_ERROR;
 508         }
 509     }
 510   else
 511     {
 512       unsigned type = type_field (node->type);
 513       if (type == ASN1_ETYPE_TAG)
 514         {
 515           *ret_len = 0;
 516           return ASN1_SUCCESS;
 517         }
 518
 519       if (asn1_get_tag_der
 520           (der + counter, der_len, &class, &len2,
 521            &tag) != ASN1_SUCCESS)
 522         return ASN1_DER_ERROR;
 523
 524       DECR_LEN(der_len, len2);
 525
 526       switch (type)
 527         {
 528         case ASN1_ETYPE_NULL:
 529         case ASN1_ETYPE_BOOLEAN:
 530         case ASN1_ETYPE_INTEGER:
 531         case ASN1_ETYPE_ENUMERATED:
 532         case ASN1_ETYPE_OBJECT_ID:
 533         case ASN1_ETYPE_GENERALSTRING:
 534         case ASN1_ETYPE_NUMERIC_STRING:
 535         case ASN1_ETYPE_IA5_STRING:
 536         case ASN1_ETYPE_TELETEX_STRING:
 537         case ASN1_ETYPE_PRINTABLE_STRING:
 538         case ASN1_ETYPE_UNIVERSAL_STRING:
 539         case ASN1_ETYPE_BMP_STRING:
 540         case ASN1_ETYPE_UTF8_STRING:
 541         case ASN1_ETYPE_VISIBLE_STRING:
 542         case ASN1_ETYPE_BIT_STRING:
 543         case ASN1_ETYPE_SEQUENCE:
 544         case ASN1_ETYPE_SEQUENCE_OF:
 545         case ASN1_ETYPE_SET:
 546         case ASN1_ETYPE_SET_OF:
 547         case ASN1_ETYPE_GENERALIZED_TIME:
 548         case ASN1_ETYPE_UTC_TIME:
 549           if ((class != _asn1_tags[type].class)
 550               || (tag != _asn1_tags[type].tag))
 551             return ASN1_DER_ERROR;
 552           break;
 553
 554         case ASN1_ETYPE_OCTET_STRING:
 555           /* OCTET STRING is handled differently to allow
 556            * BER encodings (structured class). */
 557           if (((class != ASN1_CLASS_UNIVERSAL)
 558                && (class != (ASN1_CLASS_UNIVERSAL | ASN1_CLASS_STRUCTURED)))
 559               || (tag != ASN1_TAG_OCTET_STRING))
 560             return ASN1_DER_ERROR;
 561           break;
 562         case ASN1_ETYPE_ANY:
 563           counter -= len2;
 564           break;
 565         case ASN1_ETYPE_CHOICE:
 566           counter -= len2;
 567           break;
 568         default:
 569           return ASN1_DER_ERROR;
 570           break;
 571         }
 572     }
 573
 574   counter += len2;
 575   *ret_len = counter;
 576   return ASN1_SUCCESS;
 577
 578 cleanup:
 579   return result;
 580 }
 581
 582 static int
 583 extract_tag_der_recursive(asn1_node node, const unsigned char *der, int der_len,
 584                        int *ret_len)
 585 {
 586 asn1_node p;
 587 int ris = ASN1_DER_ERROR;
 588
 589   if (type_field (node->type) == ASN1_ETYPE_CHOICE)
 590     {
 591       p = node->down;
 592       while (p)
 593         {
 594           ris = _asn1_extract_tag_der (p, der, der_len, ret_len);
 595           if (ris == ASN1_SUCCESS)
 596             break;
 597           p = p->right;
 598         }
 599
 600       *ret_len = 0;
 601       return ris;
 602     }
 603   else
 604     return _asn1_extract_tag_der (node, der, der_len, ret_len);
 605 }
 606
 607 static int
 608 _asn1_delete_not_used (asn1_node node)
 609 {
 610   asn1_node p, p2;
 611
 612   if (node == NULL)
 613     return ASN1_ELEMENT_NOT_FOUND;
 614
 615   p = node;
 616   while (p)
 617     {
 618       if (p->type & CONST_NOT_USED)
 619         {
 620           p2 = NULL;
 621           if (p != node)
 622             {
 623               p2 = _asn1_find_left (p);
 624               if (!p2)
 625                 p2 = _asn1_get_up (p);
 626             }
 627           asn1_delete_structure (&p);
 628           p = p2;
 629         }
 630
 631       if (!p)
 632         break;                  /* reach node */
 633
 634       if (p->down)
 635         {
 636           p = p->down;
 637         }
 638       else
 639         {
 640           if (p == node)
 641             p = NULL;
 642           else if (p->right)
 643             p = p->right;
 644           else
 645             {
 646               while (1)
 647                 {
 648                   p = _asn1_get_up (p);
 649                   if (p == node)
 650                     {
 651                       p = NULL;
 652                       break;
 653                     }
 654                   if (p->right)
 655                     {
 656                       p = p->right;
 657                       break;
 658                     }
 659                 }
 660             }
 661         }
 662     }
 663   return ASN1_SUCCESS;
 664 }
 665
 666 static int
 667 _asn1_extract_der_octet (asn1_node node, const unsigned char *der,
 668                          int der_len)
 669 {
 670   int len2, len3;
 671   int counter, counter_end;
 672   int result;
 673
 674   len2 = asn1_get_length_der (der, der_len, &len3);
 675   if (len2 < -1)
 676     return ASN1_DER_ERROR;
 677
 678   counter = len3 + 1;
 679
 680   if (len2 == -1)
 681     counter_end = der_len - 2;
 682   else
 683     counter_end = der_len;
 684
 685   while (counter < counter_end)
 686     {
 687       len2 = asn1_get_length_der (der + counter, der_len, &len3);
 688
 689       if (len2 < -1)
 690         return ASN1_DER_ERROR;
 691
 692       if (len2 >= 0)
 693         {
 694           DECR_LEN(der_len, len2+len3);
 695           _asn1_append_value (node, der + counter + len3, len2);
 696         }
 697       else
 698         {                       /* indefinite */
 699           DECR_LEN(der_len, len3);
 700           result =
 701             _asn1_extract_der_octet (node, der + counter + len3,
 702                                      der_len);
 703           if (result != ASN1_SUCCESS)
 704             return result;
 705           len2 = 0;
 706         }
 707
 708       DECR_LEN(der_len, 1);
 709       counter += len2 + len3 + 1;
 710     }
 711
 712   return ASN1_SUCCESS;
 713
 714 cleanup:
 715   return result;
 716 }
 717
 718 static int
 719 _asn1_get_octet_string (asn1_node node, const unsigned char *der, int der_len, int *len)
 720 {
 721   int len2, len3, counter, tot_len, indefinite;
 722   int result;
 723
 724   counter = 0;
 725
 726   if (*(der - 1) & ASN1_CLASS_STRUCTURED)
 727     {
 728       tot_len = 0;
 729       indefinite = asn1_get_length_der (der, der_len, &len3);
 730       if (indefinite < -1)
 731         return ASN1_DER_ERROR;
 732
 733       counter += len3;
 734       DECR_LEN(der_len, len3);
 735
 736       if (indefinite >= 0)
 737         indefinite += len3;
 738
 739       while (1)
 740         {
 741           if (indefinite == -1)
 742             {
 743               if (HAVE_TWO(der_len) && (der[counter] == 0) && (der[counter + 1] == 0))
 744                 {
 745                   counter += 2;
 746                   DECR_LEN(der_len, 2);
 747                   break;
 748                 }
 749             }
 750           else if (counter >= indefinite)
 751             break;
 752
 753           DECR_LEN(der_len, 1);
 754           if (der[counter] != ASN1_TAG_OCTET_STRING)
 755             return ASN1_DER_ERROR;
 756
 757           counter++;
 758
 759           len2 = asn1_get_length_der (der + counter, der_len, &len3);
 760           if (len2 <= 0)
 761             return ASN1_DER_ERROR;
 762
 763           DECR_LEN(der_len, len3 + len2);
 764           counter += len3 + len2;
 765
 766           tot_len += len2;
 767         }
 768
 769       /* copy */
 770       if (node)
 771         {
 772           unsigned char temp[ASN1_MAX_LENGTH_SIZE];
 773           int ret;
 774
 775           len2 = sizeof (temp);
 776
 777           asn1_length_der (tot_len, temp, &len2);
 778           _asn1_set_value (node, temp, len2);
 779
 780           ret = _asn1_extract_der_octet (node, der, der_len);
 781           if (ret != ASN1_SUCCESS)
 782             return ret;
 783
 784         }
 785     }
 786   else
 787     {                           /* NOT STRUCTURED */
 788       len2 = asn1_get_length_der (der, der_len, &len3);
 789       if (len2 < 0)
 790         return ASN1_DER_ERROR;
 791
 792       DECR_LEN(der_len, len3+len2);
 793       counter = len3 + len2;
 794       if (node)
 795         _asn1_set_value (node, der, counter);
 796     }
 797
 798   *len = counter;
 799   return ASN1_SUCCESS;
 800
 801 cleanup:
 802   return result;
 803 }
 804
 805 static int
 806 _asn1_get_indefinite_length_string (const unsigned char *der,
 807                                     int der_len, int *len)
 808 {
 809   int len2, len3, counter, indefinite;
 810   int result;
 811   unsigned long tag;
 812   unsigned char class;
 813
 814   counter = indefinite = 0;
 815
 816   while (1)
 817     {
 818       if (HAVE_TWO(der_len) && (der[counter] == 0) && (der[counter + 1] == 0))
 819         {
 820           counter += 2;
 821           DECR_LEN(der_len, 2);
 822
 823           indefinite--;
 824           if (indefinite <= 0)
 825             break;
 826           else
 827             continue;
 828         }
 829
 830       if (asn1_get_tag_der
 831           (der + counter, der_len, &class, &len2,
 832            &tag) != ASN1_SUCCESS)
 833         return ASN1_DER_ERROR;
 834
 835       DECR_LEN(der_len, len2);
 836       counter += len2;
 837
 838       len2 = asn1_get_length_der (der + counter, der_len, &len3);
 839       if (len2 < -1)
 840         return ASN1_DER_ERROR;
 841
 842       if (len2 == -1)
 843         {
 844           indefinite++;
 845           counter += 1;
 846           DECR_LEN(der_len, 1);
 847         }
 848       else
 849         {
 850           counter += len2 + len3;
 851           DECR_LEN(der_len, len2+len3);
 852         }
 853     }
 854
 855   *len = counter;
 856   return ASN1_SUCCESS;
 857
 858 cleanup:
 859   return result;
 860 }
 861
 862 static void delete_unneeded_choice_fields(asn1_node p)
 863 {
 864   asn1_node p2;
 865
 866   while (p->right)
 867     {
 868       p2 = p->right;
 869       asn1_delete_structure (&p2);
 870     }
 871 }
 872
 873
 874
 875 /**
 876  * asn1_der_decoding:
 877  * @element: pointer to an ASN1 structure.
 878  * @ider: vector that contains the DER encoding.
 879  * @ider_len: number of bytes of *@ider: @ider[0]..@ider[len-1].
 880  * @errorDescription: null-terminated string contains details when an
 881  *   error occurred.
 882  *
 883  * Fill the structure *@element with values of a DER encoding
 884  * string. The structure must just be created with function
 885  * asn1_create_element().
 886  *
 887  * Note that the *@element variable is provided as a pointer for
 888  * historical reasons.
 889  *
 890  * Returns: %ASN1_SUCCESS if DER encoding OK, %ASN1_ELEMENT_NOT_FOUND
 891  *   if @ELEMENT is %NULL, and %ASN1_TAG_ERROR or
 892  *   %ASN1_DER_ERROR if the der encoding doesn't match the structure
 893  *   name (*@ELEMENT deleted).
 894  **/
 895 int
 896 asn1_der_decoding (asn1_node * element, const void *ider, int ider_len,
 897                    char *errorDescription)
 898 {
 899   asn1_node node, p, p2, p3;
 900   char temp[128];
 901   int counter, len2, len3, len4, move, ris, tlen;
 902   asn1_node ptail = NULL;
 903   unsigned char class;
 904   unsigned long tag;
 905   int indefinite, result, total_len = ider_len;
 906   const unsigned char *der = ider;
 907
 908   node = *element;
 909
 910   if (errorDescription != NULL)
 911     errorDescription[0] = 0;
 912
 913   if (node == NULL)
 914     return ASN1_ELEMENT_NOT_FOUND;
 915
 916   if (node->type & CONST_OPTION)
 917     {
 918       result = ASN1_GENERIC_ERROR;
 919       warn();
 920       goto cleanup;
 921     }
 922
 923   counter = 0;
 924   move = DOWN;
 925   p = node;
 926   while (1)
 927     {
 928       ris = ASN1_SUCCESS;
 929       if (move != UP)
 930         {
 931           if (p->type & CONST_SET)
 932             {
 933               p2 = _asn1_get_up (p);
 934               len2 = p2->tmp_ival;
 935               if (len2 == -1)
 936                 {
 937                   if (HAVE_TWO(ider_len) && !der[counter] && !der[counter + 1])
 938                     {
 939                       p = p2;
 940                       move = UP;
 941                       counter += 2;
 942                       DECR_LEN(ider_len, 2);
 943                       continue;
 944                     }
 945                 }
 946               else if (counter == len2)
 947                 {
 948                   p = p2;
 949                   move = UP;
 950                   continue;
 951                 }
 952               else if (counter > len2)
 953                 {
 954                   result = ASN1_DER_ERROR;
 955                   warn();
 956                   goto cleanup;
 957                 }
 958               p2 = p2->down;
 959               while (p2)
 960                 {
 961                   if ((p2->type & CONST_SET) && (p2->type & CONST_NOT_USED))
 962                     {
 963                       ris =
 964                           extract_tag_der_recursive (p2, der + counter,
 965                                                      ider_len, &len2);
 966                       if (ris == ASN1_SUCCESS)
 967                         {
 968                           p2->type &= ~CONST_NOT_USED;
 969                           p = p2;
 970                           break;
 971                         }
 972                     }
 973                   p2 = p2->right;
 974                 }
 975               if (p2 == NULL)
 976                 {
 977                   result = ASN1_DER_ERROR;
 978                   warn();
 979                   goto cleanup;
 980                 }
 981             }
 982
 983           /* the position in the DER structure this starts */
 984           p->start = counter;
 985           p->end = total_len;
 986
 987           if ((p->type & CONST_OPTION) || (p->type & CONST_DEFAULT))
 988             {
 989               p2 = _asn1_get_up (p);
 990               len2 = p2->tmp_ival;
 991               if (counter == len2)
 992                 {
 993                   if (p->right)
 994                     {
 995                       p2 = p->right;
 996                       move = RIGHT;
 997                     }
 998                   else
 999                     move = UP;
1000
1001                   if (p->type & CONST_OPTION)
1002                     asn1_delete_structure (&p);
1003
1004                   p = p2;
1005                   continue;
1006                 }
1007             }
1008
1009           if (type_field (p->type) == ASN1_ETYPE_CHOICE)
1010             {
1011               while (p->down)
1012                 {
1013                   ris =
1014                       extract_tag_der_recursive (p->down, der + counter,
1015                                                  ider_len, &len2);
1016
1017                   if (ris == ASN1_SUCCESS)
1018                     {
1019                       delete_unneeded_choice_fields(p->down);
1020                       break;
1021                     }
1022                   else if (ris == ASN1_ERROR_TYPE_ANY)
1023                     {
1024                       result = ASN1_ERROR_TYPE_ANY;
1025                       warn();
1026                       goto cleanup;
1027                     }
1028                   else
1029                     {
1030                       p2 = p->down;
1031                       asn1_delete_structure (&p2);
1032                     }
1033                 }
1034
1035               if (p->down == NULL)
1036                 {
1037                   if (!(p->type & CONST_OPTION))
1038                     {
1039                       result = ASN1_DER_ERROR;
1040                       warn();
1041                       goto cleanup;
1042                     }
1043                 }
1044               else if (type_field (p->type) != ASN1_ETYPE_CHOICE)
1045                 p = p->down;
1046
1047               p->start = counter;
1048             }
1049
1050           if ((p->type & CONST_OPTION) || (p->type & CONST_DEFAULT))
1051             {
1052               p2 = _asn1_get_up (p);
1053               len2 = p2->tmp_ival;
1054
1055               if ((len2 != -1) && (counter > len2))
1056                 ris = ASN1_TAG_ERROR;
1057             }
1058
1059           if (ris == ASN1_SUCCESS)
1060             ris =
1061               extract_tag_der_recursive (p, der + counter, ider_len, &len2);
1062
1063           if (ris != ASN1_SUCCESS)
1064             {
1065               if (p->type & CONST_OPTION)
1066                 {
1067                   p->type |= CONST_NOT_USED;
1068                   move = RIGHT;
1069                 }
1070               else if (p->type & CONST_DEFAULT)
1071                 {
1072                   _asn1_set_value (p, NULL, 0);
1073                   move = RIGHT;
1074                 }
1075               else
1076                 {
1077                   if (errorDescription != NULL)
1078                     _asn1_error_description_tag_error (p, errorDescription);
1079
1080                   result = ASN1_TAG_ERROR;
1081                   warn();
1082                   goto cleanup;
1083                 }
1084             }
1085           else
1086             {
1087               DECR_LEN(ider_len, len2);
1088               counter += len2;
1089             }
1090         }
1091
1092       if (ris == ASN1_SUCCESS)
1093         {
1094           switch (type_field (p->type))
1095             {
1096             case ASN1_ETYPE_NULL:
1097               DECR_LEN(ider_len, 1);
1098               if (der[counter])
1099                 {
1100                   result = ASN1_DER_ERROR;
1101                   warn();
1102                   goto cleanup;
1103                 }
1104               counter++;
1105               move = RIGHT;
1106               break;
1107             case ASN1_ETYPE_BOOLEAN:
1108               DECR_LEN(ider_len, 2);
1109
1110               if (der[counter++] != 1)
1111                 {
1112                   result = ASN1_DER_ERROR;
1113                   warn();
1114                   goto cleanup;
1115                 }
1116               if (der[counter++] == 0)
1117                 _asn1_set_value (p, "F", 1);
1118               else
1119                 _asn1_set_value (p, "T", 1);
1120               move = RIGHT;
1121               break;
1122             case ASN1_ETYPE_INTEGER:
1123             case ASN1_ETYPE_ENUMERATED:
1124               len2 =
1125                 asn1_get_length_der (der + counter, ider_len, &len3);
1126               if (len2 < 0)
1127                 {
1128                   result = ASN1_DER_ERROR;
1129                   warn();
1130                   goto cleanup;
1131                 }
1132
1133               DECR_LEN(ider_len, len3+len2);
1134
1135               _asn1_set_value (p, der + counter, len3 + len2);
1136               counter += len3 + len2;
1137               move = RIGHT;
1138               break;
1139             case ASN1_ETYPE_OBJECT_ID:
1140               result =
1141                 _asn1_get_objectid_der (der + counter, ider_len, &len2,
1142                                         temp, sizeof (temp));
1143               if (result != ASN1_SUCCESS)
1144                 {
1145                   warn();
1146                   goto cleanup;
1147                 }
1148
1149               DECR_LEN(ider_len, len2);
1150
1151               tlen = strlen (temp);
1152               if (tlen > 0)
1153                 _asn1_set_value (p, temp, tlen + 1);
1154
1155               counter += len2;
1156               move = RIGHT;
1157               break;
1158             case ASN1_ETYPE_GENERALIZED_TIME:
1159             case ASN1_ETYPE_UTC_TIME:
1160               result =
1161                 _asn1_get_time_der (der + counter, ider_len, &len2, temp,
1162                                     sizeof (temp) - 1);
1163               if (result != ASN1_SUCCESS)
1164                 {
1165                   warn();
1166                   goto cleanup;
1167                 }
1168
1169               DECR_LEN(ider_len, len2);
1170
1171               tlen = strlen (temp);
1172               if (tlen > 0)
1173                 _asn1_set_value (p, temp, tlen);
1174
1175               counter += len2;
1176               move = RIGHT;
1177               break;
1178             case ASN1_ETYPE_OCTET_STRING:
1179               result = _asn1_get_octet_string (p, der + counter, ider_len, &len3);
1180               if (result != ASN1_SUCCESS)
1181                 {
1182                   warn();
1183                   goto cleanup;
1184                 }
1185
1186               DECR_LEN(ider_len, len3);
1187               counter += len3;
1188               move = RIGHT;
1189               break;
1190             case ASN1_ETYPE_GENERALSTRING:
1191             case ASN1_ETYPE_NUMERIC_STRING:
1192             case ASN1_ETYPE_IA5_STRING:
1193             case ASN1_ETYPE_TELETEX_STRING:
1194             case ASN1_ETYPE_PRINTABLE_STRING:
1195             case ASN1_ETYPE_UNIVERSAL_STRING:
1196             case ASN1_ETYPE_BMP_STRING:
1197             case ASN1_ETYPE_UTF8_STRING:
1198             case ASN1_ETYPE_VISIBLE_STRING:
1199             case ASN1_ETYPE_BIT_STRING:
1200               len2 =
1201                 asn1_get_length_der (der + counter, ider_len, &len3);
1202               if (len2 < 0)
1203                 {
1204                   result = ASN1_DER_ERROR;
1205                   warn();
1206                   goto cleanup;
1207                 }
1208
1209               DECR_LEN(ider_len, len3+len2);
1210
1211               _asn1_set_value (p, der + counter, len3 + len2);
1212               counter += len3 + len2;
1213               move = RIGHT;
1214               break;
1215             case ASN1_ETYPE_SEQUENCE:
1216             case ASN1_ETYPE_SET:
1217               if (move == UP)
1218                 {
1219                   len2 = p->tmp_ival;
1220                   p->tmp_ival = 0;
1221                   if (len2 == -1)
1222                     {           /* indefinite length method */
1223                       DECR_LEN(ider_len, 2);
1224                       if ((der[counter]) || der[counter + 1])
1225                         {
1226                           result = ASN1_DER_ERROR;
1227                           warn();
1228                           goto cleanup;
1229                         }
1230                       counter += 2;
1231                     }
1232                   else
1233                     {           /* definite length method */
1234                       if (len2 != counter)
1235                         {
1236                           result = ASN1_DER_ERROR;
1237                           warn();
1238                           goto cleanup;
1239                         }
1240                     }
1241                   move = RIGHT;
1242                 }
1243               else
1244                 {               /* move==DOWN || move==RIGHT */
1245                   len3 =
1246                     asn1_get_length_der (der + counter, ider_len, &len2);
1247                   if (len3 < -1)
1248                     {
1249                       result = ASN1_DER_ERROR;
1250                       warn();
1251                       goto cleanup;
1252                     }
1253
1254                   DECR_LEN(ider_len, len2);
1255                   counter += len2;
1256
1257                   if (len3 > 0)
1258                     {
1259                       p->tmp_ival = counter + len3;
1260                       move = DOWN;
1261                     }
1262                   else if (len3 == 0)
1263                     {
1264                       p2 = p->down;
1265                       while (p2)
1266                         {
1267                           if (type_field (p2->type) != ASN1_ETYPE_TAG)
1268                             {
1269                               p3 = p2->right;
1270                               asn1_delete_structure (&p2);
1271                               p2 = p3;
1272                             }
1273                           else
1274                             p2 = p2->right;
1275                         }
1276                       move = RIGHT;
1277                     }
1278                   else
1279                     {           /* indefinite length method */
1280                       p->tmp_ival = -1;
1281                       move = DOWN;
1282                     }
1283                 }
1284               break;
1285             case ASN1_ETYPE_SEQUENCE_OF:
1286             case ASN1_ETYPE_SET_OF:
1287               if (move == UP)
1288                 {
1289                   len2 = p->tmp_ival;
1290                   if (len2 == -1)
1291                     {           /* indefinite length method */
1292                       if (!HAVE_TWO(ider_len) || ((der[counter]) || der[counter + 1]))
1293                         {
1294                           _asn1_append_sequence_set (p, &ptail);
1295                           p = ptail;
1296                           move = RIGHT;
1297                           continue;
1298                         }
1299
1300                       p->tmp_ival = 0;
1301                       ptail = NULL; /* finished decoding this structure */
1302                       DECR_LEN(ider_len, 2);
1303                       counter += 2;
1304                     }
1305                   else
1306                     {           /* definite length method */
1307                       if (len2 > counter)
1308                         {
1309                           _asn1_append_sequence_set (p, &ptail);
1310                           p = ptail;
1311                           move = RIGHT;
1312                           continue;
1313                         }
1314
1315                       p->tmp_ival = 0;
1316                       ptail = NULL; /* finished decoding this structure */
1317
1318                       if (len2 != counter)
1319                         {
1320                           result = ASN1_DER_ERROR;
1321                           warn();
1322                           goto cleanup;
1323                         }
1324                     }
1325                 }
1326               else
1327                 {               /* move==DOWN || move==RIGHT */
1328                   len3 =
1329                     asn1_get_length_der (der + counter, ider_len, &len2);
1330                   if (len3 < -1)
1331                     {
1332                       result = ASN1_DER_ERROR;
1333                       warn();
1334                       goto cleanup;
1335                     }
1336
1337                   DECR_LEN(ider_len, len2);
1338                   counter += len2;
1339                   if (len3)
1340                     {
1341                       if (len3 > 0)
1342                         {       /* definite length method */
1343                           p->tmp_ival = counter + len3;
1344                         }
1345                       else
1346                         {       /* indefinite length method */
1347                           p->tmp_ival = -1;
1348                         }
1349                       p2 = p->down;
1350                       while ((type_field (p2->type) == ASN1_ETYPE_TAG)
1351                              || (type_field (p2->type) == ASN1_ETYPE_SIZE))
1352                         p2 = p2->right;
1353                       if (p2->right == NULL)
1354                         _asn1_append_sequence_set (p, &ptail);
1355                       p = p2;
1356                     }
1357                 }
1358               move = RIGHT;
1359               break;
1360             case ASN1_ETYPE_ANY:
1361               if (asn1_get_tag_der
1362                   (der + counter, ider_len, &class, &len2,
1363                    &tag) != ASN1_SUCCESS)
1364                 {
1365                   result = ASN1_DER_ERROR;
1366                   warn();
1367                   goto cleanup;
1368                 }
1369
1370               DECR_LEN(ider_len, len2);
1371
1372               len4 =
1373                 asn1_get_length_der (der + counter + len2,
1374                                      ider_len, &len3);
1375               if (len4 < -1)
1376                 {
1377                   result = ASN1_DER_ERROR;
1378                   warn();
1379                   goto cleanup;
1380                 }
1381               if (len4 != -1) /* definite */
1382                 {
1383                   len2 += len4;
1384
1385                   DECR_LEN(ider_len, len4+len3);
1386                   _asn1_set_value_lv (p, der + counter, len2 + len3);
1387                   counter += len2 + len3;
1388                 }
1389               else /* == -1 */
1390                 {               /* indefinite length */
1391                   ider_len += len2; /* undo DECR_LEN */
1392
1393                   if (counter == 0)
1394                     {
1395                       result = ASN1_DER_ERROR;
1396                       warn();
1397                       goto cleanup;
1398                     }
1399
1400                   /* Check indefinite lenth method in an EXPLICIT TAG */
1401                   if ((p->type & CONST_TAG) && (der[counter - 1] == 0x80))
1402                     indefinite = 1;
1403                   else
1404                     indefinite = 0;
1405
1406                   result =
1407                     _asn1_get_indefinite_length_string (der + counter, ider_len, &len2);
1408                   if (result != ASN1_SUCCESS)
1409                     {
1410                       warn();
1411                       goto cleanup;
1412                     }
1413
1414                   DECR_LEN(ider_len, len2);
1415                   _asn1_set_value_lv (p, der + counter, len2);
1416                   counter += len2;
1417
1418                   /* Check if a couple of 0x00 are present due to an EXPLICIT TAG with
1419                      an indefinite length method. */
1420                   if (indefinite)
1421                     {
1422                       DECR_LEN(ider_len, 2);
1423                       if (!der[counter] && !der[counter + 1])
1424                         {
1425                           counter += 2;
1426                         }
1427                       else
1428                         {
1429                           result = ASN1_DER_ERROR;
1430                           warn();
1431                           goto cleanup;
1432                         }
1433                     }
1434                 }
1435               move = RIGHT;
1436               break;
1437             default:
1438               move = (move == UP) ? RIGHT : DOWN;
1439               break;
1440             }
1441         }
1442
1443       if (p)
1444         {
1445           p->end = counter - 1;
1446         }
1447
1448       if (p == node && move != DOWN)
1449         break;
1450
1451       if (move == DOWN)
1452         {
1453           if (p->down)
1454             p = p->down;
1455           else
1456             move = RIGHT;
1457         }
1458       if ((move == RIGHT) && !(p->type & CONST_SET))
1459         {
1460           if (p->right)
1461             p = p->right;
1462           else
1463             move = UP;
1464         }
1465       if (move == UP)
1466         p = _asn1_get_up (p);
1467     }
1468
1469   _asn1_delete_not_used (*element);
1470
1471   if (ider_len != 0)
1472     {
1473       warn();
1474       result = ASN1_DER_ERROR;
1475       goto cleanup;
1476     }
1477
1478   return ASN1_SUCCESS;
1479
1480 cleanup:
1481   asn1_delete_structure (element);
1482   return result;
1483 }
1484
1485 #define FOUND        1
1486 #define SAME_BRANCH  2
1487 #define OTHER_BRANCH 3
1488 #define EXIT         4
1489
1490 /**
1491  * asn1_der_decoding_element:
1492  * @structure: pointer to an ASN1 structure
1493  * @elementName: name of the element to fill
1494  * @ider: vector that contains the DER encoding of the whole structure.
1495  * @len: number of bytes of *der: der[0]..der[len-1]
1496  * @errorDescription: null-terminated string contains details when an
1497  *   error occurred.
1498  *
1499  * Fill the element named @ELEMENTNAME with values of a DER encoding
1500  * string.  The structure must just be created with function
1501  * asn1_create_element().  The DER vector must contain the encoding
1502  * string of the whole @STRUCTURE.  If an error occurs during the
1503  * decoding procedure, the *@STRUCTURE is deleted and set equal to
1504  * %NULL.
1505  *
1506  * This function is deprecated and may just be an alias to asn1_der_decoding
1507  * in future versions. Use asn1_der_decoding() instead.
1508  *
1509  * Returns: %ASN1_SUCCESS if DER encoding OK, %ASN1_ELEMENT_NOT_FOUND
1510  *   if ELEMENT is %NULL or @elementName == NULL, and
1511  *   %ASN1_TAG_ERROR or %ASN1_DER_ERROR if the der encoding doesn't
1512  *   match the structure @structure (*ELEMENT deleted).
1513  **/
1514 int
1515 asn1_der_decoding_element (asn1_node * structure, const char *elementName,
1516                            const void *ider, int len, char *errorDescription)
1517 {
1518   return asn1_der_decoding(structure, ider, len, errorDescription);
1519 }
1520
1521 /**
1522  * asn1_der_decoding_startEnd:
1523  * @element: pointer to an ASN1 element
1524  * @ider: vector that contains the DER encoding.
1525  * @ider_len: number of bytes of *@ider: @ider[0]..@ider[len-1]
1526  * @name_element: an element of NAME structure.
1527  * @start: the position of the first byte of NAME_ELEMENT decoding
1528  *   (@ider[*start])
1529  * @end: the position of the last byte of NAME_ELEMENT decoding
1530  *  (@ider[*end])
1531  *
1532  * Find the start and end point of an element in a DER encoding
1533  * string. I mean that if you have a der encoding and you have already
1534  * used the function asn1_der_decoding() to fill a structure, it may
1535  * happen that you want to find the piece of string concerning an
1536  * element of the structure.
1537  *
1538  * One example is the sequence "tbsCertificate" inside an X509
1539  * certificate.
1540  *
1541  * Note that since libtasn1 3.7 the @ider and @ider_len parameters
1542  * can be omitted, if the element is already decoded using asn1_der_decoding().
1543  *
1544  * Returns: %ASN1_SUCCESS if DER encoding OK, %ASN1_ELEMENT_NOT_FOUND
1545  *   if ELEMENT is %asn1_node EMPTY or @name_element is not a valid
1546  *   element, %ASN1_TAG_ERROR or %ASN1_DER_ERROR if the der encoding
1547  *   doesn't match the structure ELEMENT.
1548  **/
1549 int
1550 asn1_der_decoding_startEnd (asn1_node element, const void *ider, int ider_len,
1551                             const char *name_element, int *start, int *end)
1552 {
1553   asn1_node node, node_to_find;
1554   int result = ASN1_DER_ERROR;
1555
1556   node = element;
1557
1558   if (node == NULL)
1559     return ASN1_ELEMENT_NOT_FOUND;
1560
1561   node_to_find = asn1_find_node (node, name_element);
1562
1563   if (node_to_find == NULL)
1564     return ASN1_ELEMENT_NOT_FOUND;
1565
1566   *start = node_to_find->start;
1567   *end = node_to_find->end;
1568
1569   if (*start == 0 && *end == 0)
1570     {
1571       if (ider == NULL || ider_len == 0)
1572         return ASN1_GENERIC_ERROR;
1573
1574       /* it seems asn1_der_decoding() wasn't called before. Do it now */
1575       result = asn1_der_decoding (&node, ider, ider_len, NULL);
1576       if (result != ASN1_SUCCESS)
1577         {
1578           warn();
1579           return result;
1580         }
1581
1582       node_to_find = asn1_find_node (node, name_element);
1583       if (node_to_find == NULL)
1584         return ASN1_ELEMENT_NOT_FOUND;
1585
1586       *start = node_to_find->start;
1587       *end = node_to_find->end;
1588     }
1589
1590   if (*end < *start)
1591     return ASN1_GENERIC_ERROR;
1592
1593   return ASN1_SUCCESS;
1594 }
1595
1596 /**
1597  * asn1_expand_any_defined_by:
1598  * @definitions: ASN1 definitions
1599  * @element: pointer to an ASN1 structure
1600  *
1601  * Expands every "ANY DEFINED BY" element of a structure created from
1602  * a DER decoding process (asn1_der_decoding function). The element
1603  * ANY must be defined by an OBJECT IDENTIFIER. The type used to
1604  * expand the element ANY is the first one following the definition of
1605  * the actual value of the OBJECT IDENTIFIER.
1606  *
1607  * Returns: %ASN1_SUCCESS if Substitution OK, %ASN1_ERROR_TYPE_ANY if
1608  *   some "ANY DEFINED BY" element couldn't be expanded due to a
1609  *   problem in OBJECT_ID -> TYPE association, or other error codes
1610  *   depending on DER decoding.
1611  **/
1612 int
1613 asn1_expand_any_defined_by (asn1_node definitions, asn1_node * element)
1614 {
1615   char name[2 * ASN1_MAX_NAME_SIZE + 1],
1616     value[ASN1_MAX_NAME_SIZE];
1617   int retCode = ASN1_SUCCESS, result;
1618   int len, len2, len3;
1619   asn1_node p, p2, p3, aux = NULL;
1620   char errorDescription[ASN1_MAX_ERROR_DESCRIPTION_SIZE];
1621   const char *definitionsName;
1622
1623   if ((definitions == NULL) || (*element == NULL))
1624     return ASN1_ELEMENT_NOT_FOUND;
1625
1626   definitionsName = definitions->name;
1627
1628   p = *element;
1629   while (p)
1630     {
1631
1632       switch (type_field (p->type))
1633         {
1634         case ASN1_ETYPE_ANY:
1635           if ((p->type & CONST_DEFINED_BY) && (p->value))
1636             {
1637               /* search the "DEF_BY" element */
1638               p2 = p->down;
1639               while ((p2) && (type_field (p2->type) != ASN1_ETYPE_CONSTANT))
1640                 p2 = p2->right;
1641
1642               if (!p2)
1643                 {
1644                   retCode = ASN1_ERROR_TYPE_ANY;
1645                   break;
1646                 }
1647
1648               p3 = _asn1_get_up (p);
1649
1650               if (!p3)
1651                 {
1652                   retCode = ASN1_ERROR_TYPE_ANY;
1653                   break;
1654                 }
1655
1656               p3 = p3->down;
1657               while (p3)
1658                 {
1659                   if (!(strcmp (p3->name, p2->name)))
1660                     break;
1661                   p3 = p3->right;
1662                 }
1663
1664               if ((!p3) || (type_field (p3->type) != ASN1_ETYPE_OBJECT_ID) ||
1665                   (p3->value == NULL))
1666                 {
1667
1668                   p3 = _asn1_get_up (p);
1669                   p3 = _asn1_get_up (p3);
1670
1671                   if (!p3)
1672                     {
1673                       retCode = ASN1_ERROR_TYPE_ANY;
1674                       break;
1675                     }
1676
1677                   p3 = p3->down;
1678
1679                   while (p3)
1680                     {
1681                       if (!(strcmp (p3->name, p2->name)))
1682                         break;
1683                       p3 = p3->right;
1684                     }
1685
1686                   if ((!p3) || (type_field (p3->type) != ASN1_ETYPE_OBJECT_ID)
1687                       || (p3->value == NULL))
1688                     {
1689                       retCode = ASN1_ERROR_TYPE_ANY;
1690                       break;
1691                     }
1692                 }
1693
1694               /* search the OBJECT_ID into definitions */
1695               p2 = definitions->down;
1696               while (p2)
1697                 {
1698                   if ((type_field (p2->type) == ASN1_ETYPE_OBJECT_ID) &&
1699                       (p2->type & CONST_ASSIGN))
1700                     {
1701                       snprintf(name, sizeof(name), "%s.%s", definitionsName, p2->name);
1702
1703                       len = ASN1_MAX_NAME_SIZE;
1704                       result =
1705                         asn1_read_value (definitions, name, value, &len);
1706
1707                       if ((result == ASN1_SUCCESS)
1708                           && (!_asn1_strcmp (p3->value, value)))
1709                         {
1710                           p2 = p2->right;       /* pointer to the structure to
1711                                                    use for expansion */
1712                           while ((p2) && (p2->type & CONST_ASSIGN))
1713                             p2 = p2->right;
1714
1715                           if (p2)
1716                             {
1717                               snprintf(name, sizeof(name), "%s.%s", definitionsName, p2->name);
1718
1719                               result =
1720                                 asn1_create_element (definitions, name, &aux);
1721                               if (result == ASN1_SUCCESS)
1722                                 {
1723                                   _asn1_cpy_name (aux, p);
1724                                   len2 =
1725                                     asn1_get_length_der (p->value,
1726                                                          p->value_len, &len3);
1727                                   if (len2 < 0)
1728                                     return ASN1_DER_ERROR;
1729
1730                                   result =
1731                                     asn1_der_decoding (&aux, p->value + len3,
1732                                                        len2,
1733                                                        errorDescription);
1734                                   if (result == ASN1_SUCCESS)
1735                                     {
1736
1737                                       _asn1_set_right (aux, p->right);
1738                                       _asn1_set_right (p, aux);
1739
1740                                       result = asn1_delete_structure (&p);
1741                                       if (result == ASN1_SUCCESS)
1742                                         {
1743                                           p = aux;
1744                                           aux = NULL;
1745                                           break;
1746                                         }
1747                                       else
1748                                         {       /* error with asn1_delete_structure */
1749                                           asn1_delete_structure (&aux);
1750                                           retCode = result;
1751                                           break;
1752                                         }
1753                                     }
1754                                   else
1755                                     {   /* error with asn1_der_decoding */
1756                                       retCode = result;
1757                                       break;
1758                                     }
1759                                 }
1760                               else
1761                                 {       /* error with asn1_create_element */
1762                                   retCode = result;
1763                                   break;
1764                                 }
1765                             }
1766                           else
1767                             {   /* error with the pointer to the structure to exapand */
1768                               retCode = ASN1_ERROR_TYPE_ANY;
1769                               break;
1770                             }
1771                         }
1772                     }
1773                   p2 = p2->right;
1774                 }               /* end while */
1775
1776               if (!p2)
1777                 {
1778                   retCode = ASN1_ERROR_TYPE_ANY;
1779                   break;
1780                 }
1781
1782             }
1783           break;
1784         default:
1785           break;
1786         }
1787
1788
1789       if (p->down)
1790         {
1791           p = p->down;
1792         }
1793       else if (p == *element)
1794         {
1795           p = NULL;
1796           break;
1797         }
1798       else if (p->right)
1799         p = p->right;
1800       else
1801         {
1802           while (1)
1803             {
1804               p = _asn1_get_up (p);
1805               if (p == *element)
1806                 {
1807                   p = NULL;
1808                   break;
1809                 }
1810               if (p->right)
1811                 {
1812                   p = p->right;
1813                   break;
1814                 }
1815             }
1816         }
1817     }
1818
1819   return retCode;
1820 }
1821
1822 /**
1823  * asn1_expand_octet_string:
1824  * @definitions: ASN1 definitions
1825  * @element: pointer to an ASN1 structure
1826  * @octetName: name of the OCTECT STRING field to expand.
1827  * @objectName: name of the OBJECT IDENTIFIER field to use to define
1828  *    the type for expansion.
1829  *
1830  * Expands an "OCTET STRING" element of a structure created from a DER
1831  * decoding process (the asn1_der_decoding() function).  The type used
1832  * for expansion is the first one following the definition of the
1833  * actual value of the OBJECT IDENTIFIER indicated by OBJECTNAME.
1834  *
1835  * Returns: %ASN1_SUCCESS if substitution OK, %ASN1_ELEMENT_NOT_FOUND
1836  *   if @objectName or @octetName are not correct,
1837  *   %ASN1_VALUE_NOT_VALID if it wasn't possible to find the type to
1838  *   use for expansion, or other errors depending on DER decoding.
1839  **/
1840 int
1841 asn1_expand_octet_string (asn1_node definitions, asn1_node * element,
1842                           const char *octetName, const char *objectName)
1843 {
1844   char name[2 * ASN1_MAX_NAME_SIZE + 1], value[ASN1_MAX_NAME_SIZE];
1845   int retCode = ASN1_SUCCESS, result;
1846   int len, len2, len3;
1847   asn1_node p2, aux = NULL;
1848   asn1_node octetNode = NULL, objectNode = NULL;
1849   char errorDescription[ASN1_MAX_ERROR_DESCRIPTION_SIZE];
1850
1851   if ((definitions == NULL) || (*element == NULL))
1852     return ASN1_ELEMENT_NOT_FOUND;
1853
1854   octetNode = asn1_find_node (*element, octetName);
1855   if (octetNode == NULL)
1856     return ASN1_ELEMENT_NOT_FOUND;
1857   if (type_field (octetNode->type) != ASN1_ETYPE_OCTET_STRING)
1858     return ASN1_ELEMENT_NOT_FOUND;
1859   if (octetNode->value == NULL)
1860     return ASN1_VALUE_NOT_FOUND;
1861
1862   objectNode = asn1_find_node (*element, objectName);
1863   if (objectNode == NULL)
1864     return ASN1_ELEMENT_NOT_FOUND;
1865
1866   if (type_field (objectNode->type) != ASN1_ETYPE_OBJECT_ID)
1867     return ASN1_ELEMENT_NOT_FOUND;
1868
1869   if (objectNode->value == NULL)
1870     return ASN1_VALUE_NOT_FOUND;
1871
1872
1873   /* search the OBJECT_ID into definitions */
1874   p2 = definitions->down;
1875   while (p2)
1876     {
1877       if ((type_field (p2->type) == ASN1_ETYPE_OBJECT_ID) &&
1878           (p2->type & CONST_ASSIGN))
1879         {
1880           strcpy (name, definitions->name);
1881           strcat (name, ".");
1882           strcat (name, p2->name);
1883
1884           len = sizeof (value);
1885           result = asn1_read_value (definitions, name, value, &len);
1886
1887           if ((result == ASN1_SUCCESS)
1888               && (!_asn1_strcmp (objectNode->value, value)))
1889             {
1890
1891               p2 = p2->right;   /* pointer to the structure to
1892                                    use for expansion */
1893               while ((p2) && (p2->type & CONST_ASSIGN))
1894                 p2 = p2->right;
1895
1896               if (p2)
1897                 {
1898                   strcpy (name, definitions->name);
1899                   strcat (name, ".");
1900                   strcat (name, p2->name);
1901
1902                   result = asn1_create_element (definitions, name, &aux);
1903                   if (result == ASN1_SUCCESS)
1904                     {
1905                       _asn1_cpy_name (aux, octetNode);
1906                       len2 =
1907                         asn1_get_length_der (octetNode->value,
1908                                              octetNode->value_len, &len3);
1909                       if (len2 < 0)
1910                         return ASN1_DER_ERROR;
1911
1912                       result =
1913                         asn1_der_decoding (&aux, octetNode->value + len3,
1914                                            len2, errorDescription);
1915                       if (result == ASN1_SUCCESS)
1916                         {
1917
1918                           _asn1_set_right (aux, octetNode->right);
1919                           _asn1_set_right (octetNode, aux);
1920
1921                           result = asn1_delete_structure (&octetNode);
1922                           if (result == ASN1_SUCCESS)
1923                             {
1924                               aux = NULL;
1925                               break;
1926                             }
1927                           else
1928                             {   /* error with asn1_delete_structure */
1929                               asn1_delete_structure (&aux);
1930                               retCode = result;
1931                               break;
1932                             }
1933                         }
1934                       else
1935                         {       /* error with asn1_der_decoding */
1936                           retCode = result;
1937                           break;
1938                         }
1939                     }
1940                   else
1941                     {           /* error with asn1_create_element */
1942                       retCode = result;
1943                       break;
1944                     }
1945                 }
1946               else
1947                 {               /* error with the pointer to the structure to exapand */
1948                   retCode = ASN1_VALUE_NOT_VALID;
1949                   break;
1950                 }
1951             }
1952         }
1953
1954       p2 = p2->right;
1955
1956     }
1957
1958   if (!p2)
1959     retCode = ASN1_VALUE_NOT_VALID;
1960
1961   return retCode;
1962 }
1963
1964 /**
1965  * asn1_decode_simple_der:
1966  * @etype: The type of the string to be encoded (ASN1_ETYPE_)
1967  * @der: the encoded string
1968  * @der_len: the bytes of the encoded string
1969  * @str: a pointer to the data
1970  * @str_len: the length of the data
1971  *
1972  * Decodes a simple DER encoded type (e.g. a string, which is not constructed).
1973  * The output is a pointer inside the @der.
1974  *
1975  * Returns: %ASN1_SUCCESS if successful or an error value.
1976  **/
1977 int
1978 asn1_decode_simple_der (unsigned int etype, const unsigned char *der,
1979                         unsigned int der_len, const unsigned char **str,
1980                         unsigned int *str_len)
1981 {
1982   int tag_len, len_len;
1983   const unsigned char *p;
1984   unsigned char class;
1985   unsigned long tag;
1986   long ret;
1987
1988   if (der == NULL || der_len == 0)
1989     return ASN1_VALUE_NOT_VALID;
1990
1991   if (ETYPE_OK (etype) == 0)
1992     return ASN1_VALUE_NOT_VALID;
1993
1994   /* doesn't handle constructed classes */
1995   if (ETYPE_CLASS (etype) != ASN1_CLASS_UNIVERSAL)
1996     return ASN1_VALUE_NOT_VALID;
1997
1998   p = der;
1999   ret = asn1_get_tag_der (p, der_len, &class, &tag_len, &tag);
2000   if (ret != ASN1_SUCCESS)
2001     return ret;
2002
2003   if (class != ETYPE_CLASS (etype) || tag != ETYPE_TAG (etype))
2004     return ASN1_DER_ERROR;
2005
2006   p += tag_len;
2007   der_len -= tag_len;
2008
2009   ret = asn1_get_length_der (p, der_len, &len_len);
2010   if (ret < 0)
2011     return ASN1_DER_ERROR;
2012
2013   p += len_len;
2014   der_len -= len_len;
2015
2016   *str_len = ret;
2017   *str = p;
2018
2019   return ASN1_SUCCESS;
2020 }