aboutsummaryrefslogtreecommitdiff
path: root/src/daemon/https/minitasn1/coding.c
blob: fe61229998486183bde86d44f868f60f11b82d4b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
/*
 *      Copyright (C) 2004, 2006 Free Software Foundation
 *      Copyright (C) 2002  Fabio Fiorina
 *
 * This file is part of LIBTASN1.
 *
 * The LIBTASN1 library is free software; you can redistribute it
 * and/or modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 */


/*****************************************************/
/* File: coding.c                                    */
/* Description: Functions to create a DER coding of  */
/*   an ASN1 type.                                   */
/*****************************************************/

#include <int.h>
#include "parser_aux.h"
#include <gstr.h>
#include "element.h"
#include <structure.h>

#define MAX_TAG_LEN 16

/******************************************************/
/* Function : MHD__asn1_error_description_value_not_found */
/* Description: creates the ErrorDescription string   */
/* for the ASN1_VALUE_NOT_FOUND error.                */
/* Parameters:                                        */
/*   node: node of the tree where the value is NULL.  */
/*   ErrorDescription: string returned.               */
/* Return:                                            */
/******************************************************/
static void
MHD__asn1_error_description_value_not_found (node_asn * node,
                                             char *ErrorDescription)
{

  if (ErrorDescription == NULL)
    return;

  Estrcpy (ErrorDescription, ":: value of element '");
  MHD__asn1_hierarchical_name (node,
                               ErrorDescription + strlen (ErrorDescription),
                               MAX_ERROR_DESCRIPTION_SIZE - 40);
  Estrcat (ErrorDescription, "' not found");

}

/**
 * MHD__asn1_length_der:
 * @len: value to convert.
 * @ans: string returned.
 * @ans_len: number of meaningful bytes of ANS (ans[0]..ans[ans_len-1]).
 *
 * Creates the DER coding for the LEN parameter (only the length).
 * The @ans buffer is pre-allocated and must have room for the output.
 **/
void
MHD__asn1_length_der (unsigned long int len, unsigned char *ans, int *ans_len)
{
  int k;
  unsigned char temp[SIZEOF_UNSIGNED_LONG_INT];

  if (len < 128)
    {
      /* short form */
      if (ans != NULL)
        ans[0] = (unsigned char) len;
      *ans_len = 1;
    }
  else
    {
      /* Long form */
      k = 0;
      while (len)
        {
          temp[k++] = len & 0xFF;
          len = len >> 8;
        }
      *ans_len = k + 1;
      if (ans != NULL)
        {
          ans[0] = ((unsigned char) k & 0x7F) + 128;
          while (k--)
            ans[*ans_len - 1 - k] = temp[k];
        }
    }
}

/******************************************************/
/* Function : MHD__asn1_tag_der                           */
/* Description: creates the DER coding for the CLASS  */
/* and TAG parameters.                                */
/* Parameters:                                        */
/*   class: value to convert.                         */
/*   tag_value: value to convert.                     */
/*   ans: string returned.                            */
/*   ans_len: number of meaningful bytes of ANS       */
/*            (ans[0]..ans[ans_len-1]).               */
/* Return:                                            */
/******************************************************/
static void
MHD__asn1_tag_der (unsigned char class, unsigned int tag_value,
                   unsigned char *ans, int *ans_len)
{
  int k;
  unsigned char temp[SIZEOF_UNSIGNED_INT];

  if (tag_value < 31)
    {
      /* short form */
      ans[0] = (class & 0xE0) + ((unsigned char) (tag_value & 0x1F));
      *ans_len = 1;
    }
  else
    {
      /* Long form */
      ans[0] = (class & 0xE0) + 31;
      k = 0;
      while (tag_value)
        {
          temp[k++] = tag_value & 0x7F;
          tag_value = tag_value >> 7;
        }
      *ans_len = k + 1;
      while (k--)
        ans[*ans_len - 1 - k] = temp[k] + 128;
      ans[*ans_len - 1] -= 128;
    }
}

/**
 * MHD__asn1_octet_der:
 * @str: OCTET string.
 * @str_len: STR length (str[0]..str[str_len-1]).
 * @der: string returned.
 * @der_len: number of meaningful bytes of DER (der[0]..der[ans_len-1]).
 *
 * Creates the DER coding for an OCTET type (length included).
 **/
void
MHD__asn1_octet_der (const unsigned char *str, int str_len,
                     unsigned char *der, int *der_len)
{
  int len_len;

  if (der == NULL || str_len < 0)
    return;
  MHD__asn1_length_der (str_len, der, &len_len);
  memcpy (der + len_len, str, str_len);
  *der_len = str_len + len_len;
}

/******************************************************/
/* Function : MHD__asn1_time_der                          */
/* Description: creates the DER coding for a TIME     */
/* type (length included).                            */
/* Parameters:                                        */
/*   str: TIME null-terminated string.                */
/*   der: string returned.                            */
/*   der_len: number of meaningful bytes of DER       */
/*            (der[0]..der[ans_len-1]). Initially it  */
/*            if must store the lenght of DER.        */
/* Return:                                            */
/*   ASN1_MEM_ERROR when DER isn't big enough         */
/*   ASN1_SUCCESS otherwise                           */
/******************************************************/
static MHD__asn1_retCode
MHD__asn1_time_der (unsigned char *str, unsigned char *der, int *der_len)
{
  int len_len;
  int max_len;

  max_len = *der_len;

  MHD__asn1_length_der (strlen ((const char *) str),
                        (max_len > 0) ? der : NULL, &len_len);

  if ((len_len + (int) strlen ((const char *) str)) <= max_len)
    memcpy (der + len_len, str, strlen ((const char *) str));
  *der_len = len_len + strlen ((const char *) str);

  if ((*der_len) > max_len)
    return ASN1_MEM_ERROR;

  return ASN1_SUCCESS;
}

/******************************************************/
/* Function : MHD__asn1_objectid_der                      */
/* Description: creates the DER coding for an         */
/* OBJECT IDENTIFIER  type (length included).         */
/* Parameters:                                        */
/*   str: OBJECT IDENTIFIER null-terminated string.   */
/*   der: string returned.                            */
/*   der_len: number of meaningful bytes of DER       */
/*            (der[0]..der[ans_len-1]). Initially it  */
/*            must store the length of DER.           */
/* Return:                                            */
/*   ASN1_MEM_ERROR when DER isn't big enough         */
/*   ASN1_SUCCESS otherwise                           */
/******************************************************/
static MHD__asn1_retCode
MHD__asn1_objectid_der (unsigned char *str, unsigned char *der, int *der_len)
{
  int len_len, counter, k, first, max_len;
  char *temp, *n_end, *n_start;
  unsigned char bit7;
  unsigned long val, val1 = 0;

  max_len = *der_len;

  temp = (char *) MHD__asn1_alloca (strlen ((const char *) str) + 2);
  if (temp == NULL)
    return ASN1_MEM_ALLOC_ERROR;

  strcpy (temp, (const char *) str);
  strcat (temp, ".");

  counter = 0;
  n_start = temp;
  while ((n_end = strchr (n_start, '.')))
    {
      *n_end = 0;
      val = strtoul (n_start, NULL, 10);
      counter++;

      if (counter == 1)
        val1 = val;
      else if (counter == 2)
        {
          if (max_len > 0)
            der[0] = 40 * val1 + val;
          *der_len = 1;
        }
      else
        {
          first = 0;
          for (k = 4; k >= 0; k--)
            {
              bit7 = (val >> (k * 7)) & 0x7F;
              if (bit7 || first || !k)
                {
                  if (k)
                    bit7 |= 0x80;
                  if (max_len > (*der_len))
                    der[*der_len] = bit7;
                  (*der_len)++;
                  first = 1;
                }
            }

        }
      n_start = n_end + 1;
    }

  MHD__asn1_length_der (*der_len, NULL, &len_len);
  if (max_len >= (*der_len + len_len))
    {
      memmove (der + len_len, der, *der_len);
      MHD__asn1_length_der (*der_len, der, &len_len);
    }
  *der_len += len_len;

  MHD__asn1_afree (temp);

  if (max_len < (*der_len))
    return ASN1_MEM_ERROR;

  return ASN1_SUCCESS;
}


const char MHD_bit_mask[] =
  { 0xFF, 0xFE, 0xFC, 0xF8, 0xF0, 0xE0, 0xC0, 0x80 };

/**
 * MHD__asn1_bit_der:
 * @str: BIT string.
 * @bit_len: number of meaningful bits in STR.
 * @der: string returned.
 * @der_len: number of meaningful bytes of DER
 *   (der[0]..der[ans_len-1]).
 *
 * Creates the DER coding for a BIT STRING type (length and pad
 * included).
 **/
void
MHD__asn1_bit_der (const unsigned char *str, int bit_len,
                   unsigned char *der, int *der_len)
{
  int len_len, len_byte, len_pad;

  if (der == NULL)
    return;
  len_byte = bit_len >> 3;
  len_pad = 8 - (bit_len & 7);
  if (len_pad == 8)
    len_pad = 0;
  else
    len_byte++;
  MHD__asn1_length_der (len_byte + 1, der, &len_len);
  der[len_len] = len_pad;
  memcpy (der + len_len + 1, str, len_byte);
  der[len_len + len_byte] &= MHD_bit_mask[len_pad];
  *der_len = len_byte + len_len + 1;
}


/******************************************************/
/* Function : MHD__asn1_complete_explicit_tag             */
/* Description: add the length coding to the EXPLICIT */
/* tags.                                              */
/* Parameters:                                        */
/*   node: pointer to the tree element.               */
/*   der: string with the DER coding of the whole tree*/
/*   counter: number of meaningful bytes of DER       */
/*            (der[0]..der[*counter-1]).              */
/*   max_len: size of der vector                      */
/* Return:                                            */
/*   ASN1_MEM_ERROR if der vector isn't big enough,   */
/*   otherwise ASN1_SUCCESS.                          */
/******************************************************/
static MHD__asn1_retCode
MHD__asn1_complete_explicit_tag (node_asn * node, unsigned char *der,
                                 int *counter, int *max_len)
{
  node_asn *p;
  int is_tag_implicit, len2, len3;
  unsigned char temp[SIZEOF_UNSIGNED_INT];

  is_tag_implicit = 0;

  if (node->type & CONST_TAG)
    {
      p = node->down;
      /* When there are nested tags we must complete them reverse to
         the order they were created. This is because completing a tag
         modifies all data within it, including the incomplete tags
         which store buffer positions -- simon@josefsson.org 2002-09-06
       */
      while (p->right)
        p = p->right;
      while (p && p != node->down->left)
        {
          if (type_field (p->type) == TYPE_TAG)
            {
              if (p->type & CONST_EXPLICIT)
                {
                  len2 = strtol (p->name, NULL, 10);
                  MHD__asn1_set_name (p, NULL);
                  MHD__asn1_length_der (*counter - len2, temp, &len3);
                  if (len3 <= (*max_len))
                    {
                      memmove (der + len2 + len3, der + len2,
                               *counter - len2);
                      memcpy (der + len2, temp, len3);
                    }
                  *max_len -= len3;
                  *counter += len3;
                  is_tag_implicit = 0;
                }
              else
                {               /* CONST_IMPLICIT */
                  if (!is_tag_implicit)
                    {
                      is_tag_implicit = 1;
                    }
                }
            }
          p = p->left;
        }
    }

  if (*max_len < 0)
    return ASN1_MEM_ERROR;

  return ASN1_SUCCESS;
}


/******************************************************/
/* Function : MHD__asn1_insert_tag_der                    */
/* Description: creates the DER coding of tags of one */
/* NODE.                                              */
/* Parameters:                                        */
/*   node: pointer to the tree element.               */
/*   der: string returned                             */
/*   counter: number of meaningful bytes of DER       */
/*            (counter[0]..der[*counter-1]).          */
/*   max_len: size of der vector                      */
/* Return:                                            */
/*   ASN1_GENERIC_ERROR if the type is unknown,       */
/*   ASN1_MEM_ERROR if der vector isn't big enough,   */
/*   otherwise ASN1_SUCCESS.                          */
/******************************************************/
static MHD__asn1_retCode
MHD__asn1_insert_tag_der (node_asn * node, unsigned char *der, int *counter,
                          int *max_len)
{
  node_asn *p;
  int tag_len, is_tag_implicit;
  unsigned char class, class_implicit = 0, temp[SIZEOF_UNSIGNED_INT * 3 + 1];
  unsigned long tag_implicit = 0;
  char tag_der[MAX_TAG_LEN];

  is_tag_implicit = 0;

  if (node->type & CONST_TAG)
    {
      p = node->down;
      while (p)
        {
          if (type_field (p->type) == TYPE_TAG)
            {
              if (p->type & CONST_APPLICATION)
                class = ASN1_CLASS_APPLICATION;
              else if (p->type & CONST_UNIVERSAL)
                class = ASN1_CLASS_UNIVERSAL;
              else if (p->type & CONST_PRIVATE)
                class = ASN1_CLASS_PRIVATE;
              else
                class = ASN1_CLASS_CONTEXT_SPECIFIC;

              if (p->type & CONST_EXPLICIT)
                {
                  if (is_tag_implicit)
                    MHD__asn1_tag_der (class_implicit, tag_implicit,
                                       (unsigned char *) tag_der, &tag_len);
                  else
                    MHD__asn1_tag_der (class | ASN1_CLASS_STRUCTURED,
                                       strtoul ((const char *) p->value, NULL,
                                                10),
                                       (unsigned char *) tag_der, &tag_len);

                  *max_len -= tag_len;
                  if (*max_len >= 0)
                    memcpy (der + *counter, tag_der, tag_len);
                  *counter += tag_len;

                  MHD__asn1_ltostr (*counter, (char *) temp);
                  MHD__asn1_set_name (p, (const char *) temp);

                  is_tag_implicit = 0;
                }
              else
                {               /* CONST_IMPLICIT */
                  if (!is_tag_implicit)
                    {
                      if ((type_field (node->type) == TYPE_SEQUENCE) ||
                          (type_field (node->type) == TYPE_SEQUENCE_OF) ||
                          (type_field (node->type) == TYPE_SET) ||
                          (type_field (node->type) == TYPE_SET_OF))
                        class |= ASN1_CLASS_STRUCTURED;
                      class_implicit = class;
                      tag_implicit =
                        strtoul ((const char *) p->value, NULL, 10);
                      is_tag_implicit = 1;
                    }
                }
            }
          p = p->right;
        }
    }

  if (is_tag_implicit)
    {
      MHD__asn1_tag_der (class_implicit, tag_implicit,
                         (unsigned char *) tag_der, &tag_len);
    }
  else
    {
      switch (type_field (node->type))
        {
        case TYPE_NULL:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_NULL,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_BOOLEAN:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_BOOLEAN,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_INTEGER:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_INTEGER,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_ENUMERATED:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_ENUMERATED,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_OBJECT_ID:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_OBJECT_ID,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_TIME:
          if (node->type & CONST_UTC)
            {
              MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_UTCTime,
                                 (unsigned char *) tag_der, &tag_len);
            }
          else
            MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_GENERALIZEDTime,
                               (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_OCTET_STRING:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_OCTET_STRING,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_GENERALSTRING:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_GENERALSTRING,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_BIT_STRING:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL, ASN1_TAG_BIT_STRING,
                             (unsigned char *) tag_der, &tag_len);
          break;
        case TYPE_SEQUENCE:
        case TYPE_SEQUENCE_OF:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL | ASN1_CLASS_STRUCTURED,
                             ASN1_TAG_SEQUENCE, (unsigned char *) tag_der,
                             &tag_len);
          break;
        case TYPE_SET:
        case TYPE_SET_OF:
          MHD__asn1_tag_der (ASN1_CLASS_UNIVERSAL | ASN1_CLASS_STRUCTURED,
                             ASN1_TAG_SET, (unsigned char *) tag_der,
                             &tag_len);
          break;
        case TYPE_TAG:
          tag_len = 0;
          break;
        case TYPE_CHOICE:
          tag_len = 0;
          break;
        case TYPE_ANY:
          tag_len = 0;
          break;
        default:
          return ASN1_GENERIC_ERROR;
        }
    }

  *max_len -= tag_len;
  if (*max_len >= 0)
    memcpy (der + *counter, tag_der, tag_len);
  *counter += tag_len;

  if (*max_len < 0)
    return ASN1_MEM_ERROR;

  return ASN1_SUCCESS;
}

/******************************************************/
/* Function : MHD__asn1_ordering_set                      */
/* Description: puts the elements of a SET type in    */
/* the correct order according to DER rules.          */
/* Parameters:                                        */
/*   der: string with the DER coding.                 */
/*   node: pointer to the SET element.                */
/* Return:                                            */
/******************************************************/
static void
MHD__asn1_ordering_set (unsigned char *der, int der_len, node_asn * node)
{
  struct vet
  {
    int end;
    unsigned long value;
    struct vet *next, *prev;
  };

  int counter, len, len2;
  struct vet *first, *last, *p_vet, *p2_vet;
  node_asn *p;
  unsigned char class, *temp;
  unsigned long tag;

  counter = 0;

  if (type_field (node->type) != TYPE_SET)
    return;

  p = node->down;
  while ((p != NULL) &&
         ((type_field (p->type) == TYPE_TAG)
          || (type_field (p->type) == TYPE_SIZE)))
    p = p->right;

  if ((p == NULL) || (p->right == NULL))
    return;

  first = last = NULL;
  while (p)
    {
      p_vet = (struct vet *) MHD__asn1_alloca (sizeof (struct vet));
      if (p_vet == NULL)
        return;

      p_vet->next = NULL;
      p_vet->prev = last;
      if (first == NULL)
        first = p_vet;
      else
        last->next = p_vet;
      last = p_vet;

      /* tag value calculation */
      if (MHD__asn1_get_tag_der
          (der + counter, der_len - counter, &class, &len2,
           &tag) != ASN1_SUCCESS)
        return;
      p_vet->value = (class << 24) | tag;
      counter += len2;

      /* extraction and length */
      len2 =
        MHD__asn1_get_length_der (der + counter, der_len - counter, &len);
      if (len2 < 0)
        return;
      counter += len + len2;

      p_vet->end = counter;
      p = p->right;
    }

  p_vet = first;

  while (p_vet)
    {
      p2_vet = p_vet->next;
      counter = 0;
      while (p2_vet)
        {
          if (p_vet->value > p2_vet->value)
            {
              /* change position */
              temp =
                (unsigned char *) MHD__asn1_alloca (p_vet->end - counter);
              if (temp == NULL)
                return;

              memcpy (temp, der + counter, p_vet->end - counter);
              memcpy (der + counter, der + p_vet->end,
                      p2_vet->end - p_vet->end);
              memcpy (der + counter + p2_vet->end - p_vet->end, temp,
                      p_vet->end - counter);
              MHD__asn1_afree (temp);

              tag = p_vet->value;
              p_vet->value = p2_vet->value;
              p2_vet->value = tag;

              p_vet->end = counter + (p2_vet->end - p_vet->end);
            }
          counter = p_vet->end;

          p2_vet = p2_vet->next;
          p_vet = p_vet->next;
        }

      if (p_vet != first)
        p_vet->prev->next = NULL;
      else
        first = NULL;
      MHD__asn1_afree (p_vet);
      p_vet = first;
    }
}

/******************************************************/
/* Function : MHD__asn1_ordering_set_of                   */
/* Description: puts the elements of a SET OF type in */
/* the correct order according to DER rules.          */
/* Parameters:                                        */
/*   der: string with the DER coding.                 */
/*   node: pointer to the SET OF element.             */
/* Return:                                            */
/******************************************************/
static void
MHD__asn1_ordering_set_of (unsigned char *der, int der_len, node_asn * node)
{
  struct vet
  {
    int end;
    struct vet *next, *prev;
  };

  int counter, len, len2, change;
  struct vet *first, *last, *p_vet, *p2_vet;
  node_asn *p;
  unsigned char *temp, class;
  unsigned long k, max;

  counter = 0;

  if (type_field (node->type) != TYPE_SET_OF)
    return;

  p = node->down;
  while ((type_field (p->type) == TYPE_TAG)
         || (type_field (p->type) == TYPE_SIZE))
    p = p->right;
  p = p->right;

  if ((p == NULL) || (p->right == NULL))
    return;

  first = last = NULL;
  while (p)
    {
      p_vet = (struct vet *) MHD__asn1_alloca (sizeof (struct vet));
      if (p_vet == NULL)
        return;

      p_vet->next = NULL;
      p_vet->prev = last;
      if (first == NULL)
        first = p_vet;
      else
        last->next = p_vet;
      last = p_vet;

      /* extraction of tag and length */
      if (der_len - counter > 0)
        {

          if (MHD__asn1_get_tag_der
              (der + counter, der_len - counter, &class, &len,
               NULL) != ASN1_SUCCESS)
            return;
          counter += len;

          len2 =
            MHD__asn1_get_length_der (der + counter, der_len - counter, &len);
          if (len2 < 0)
            return;
          counter += len + len2;
        }

      p_vet->end = counter;
      p = p->right;
    }

  p_vet = first;

  while (p_vet)
    {
      p2_vet = p_vet->next;
      counter = 0;
      while (p2_vet)
        {
          if ((p_vet->end - counter) > (p2_vet->end - p_vet->end))
            max = p_vet->end - counter;
          else
            max = p2_vet->end - p_vet->end;

          change = -1;
          for (k = 0; k < max; k++)
            if (der[counter + k] > der[p_vet->end + k])
              {
                change = 1;
                break;
              }
            else if (der[counter + k] < der[p_vet->end + k])
              {
                change = 0;
                break;
              }

          if ((change == -1)
              && ((p_vet->end - counter) > (p2_vet->end - p_vet->end)))
            change = 1;

          if (change == 1)
            {
              /* change position */
              temp =
                (unsigned char *) MHD__asn1_alloca (p_vet->end - counter);
              if (temp == NULL)
                return;

              memcpy (temp, der + counter, (p_vet->end) - counter);
              memcpy (der + counter, der + (p_vet->end),
                      (p2_vet->end) - (p_vet->end));
              memcpy (der + counter + (p2_vet->end) - (p_vet->end), temp,
                      (p_vet->end) - counter);
              MHD__asn1_afree (temp);

              p_vet->end = counter + (p2_vet->end - p_vet->end);
            }
          counter = p_vet->end;

          p2_vet = p2_vet->next;
          p_vet = p_vet->next;
        }

      if (p_vet != first)
        p_vet->prev->next = NULL;
      else
        first = NULL;
      MHD__asn1_afree (p_vet);
      p_vet = first;
    }
}

/**
  * MHD__asn1_der_coding - Creates the DER encoding for the NAME structure
  * @element: pointer to an ASN1 element
  * @name: the name of the structure you want to encode (it must be
  *   inside *POINTER).
  * @ider: vector that will contain the DER encoding. DER must be a
  *   pointer to memory cells already allocated.
  * @len: number of bytes of *@ider: @ider[0]..@ider[len-1], Initialy
  *   holds the sizeof of der vector.
  * @errorDescription : return the error description or an empty
  *   string if success.
  *
  * Creates the DER encoding for the NAME structure (inside *POINTER
  * structure).
  *
  * Returns:
  *
  *   ASN1_SUCCESS: DER encoding OK.
  *
  *   ASN1_ELEMENT_NOT_FOUND: NAME is not a valid element.
  *
  *   ASN1_VALUE_NOT_FOUND: There is an element without a value.
  *
  *   ASN1_MEM_ERROR: @ider vector isn't big enough. Also in this case
  *     LEN will contain the length needed.
  *
  **/
MHD__asn1_retCode
MHD__asn1_der_coding (ASN1_TYPE element, const char *name, void *ider,
                      int *len, char *ErrorDescription)
{
  node_asn *node, *p, *p2;
  char temp[SIZEOF_UNSIGNED_LONG_INT * 3 + 1];
  int counter, counter_old, len2, len3, tlen, move, max_len, max_len_old;
  MHD__asn1_retCode err;
  unsigned char *der = ider;

  node = MHD__asn1_find_node (element, name);
  if (node == NULL)
    return ASN1_ELEMENT_NOT_FOUND;

  /* Node is now a locally allocated variable.
   * That is because in some point we modify the
   * structure, and I don't know why! --nmav
   */
  node = MHD__asn1_copy_structure3 (node);
  if (node == NULL)
    return ASN1_ELEMENT_NOT_FOUND;

  max_len = *len;

  counter = 0;
  move = DOWN;
  p = node;
  while (1)
    {

      counter_old = counter;
      max_len_old = max_len;
      if (move != UP)
        {
          err = MHD__asn1_insert_tag_der (p, der, &counter, &max_len);
          if (err != ASN1_SUCCESS && err != ASN1_MEM_ERROR)
            goto error;
        }
      switch (type_field (p->type))
        {
        case TYPE_NULL:
          max_len--;
          if (max_len >= 0)
            der[counter] = 0;
          counter++;
          move = RIGHT;
          break;
        case TYPE_BOOLEAN:
          if ((p->type & CONST_DEFAULT) && (p->value == NULL))
            {
              counter = counter_old;
              max_len = max_len_old;
            }
          else
            {
              if (p->value == NULL)
                {
                  MHD__asn1_error_description_value_not_found (p,
                                                               ErrorDescription);
                  err = ASN1_VALUE_NOT_FOUND;
                  goto error;
                }
              max_len -= 2;
              if (max_len >= 0)
                {
                  der[counter++] = 1;
                  if (p->value[0] == 'F')
                    der[counter++] = 0;
                  else
                    der[counter++] = 0xFF;
                }
              else
                counter += 2;
            }
          move = RIGHT;
          break;
        case TYPE_INTEGER:
        case TYPE_ENUMERATED:
          if ((p->type & CONST_DEFAULT) && (p->value == NULL))
            {
              counter = counter_old;
              max_len = max_len_old;
            }
          else
            {
              if (p->value == NULL)
                {
                  MHD__asn1_error_description_value_not_found (p,
                                                               ErrorDescription);
                  err = ASN1_VALUE_NOT_FOUND;
                  goto error;
                }
              len2 = MHD__asn1_get_length_der (p->value, p->value_len, &len3);
              if (len2 < 0)
                {
                  err = ASN1_DER_ERROR;
                  goto error;
                }
              max_len -= len2 + len3;
              if (max_len >= 0)
                memcpy (der + counter, p->value, len3 + len2);
              counter += len3 + len2;
            }
          move = RIGHT;
          break;
        case TYPE_OBJECT_ID:
          if ((p->type & CONST_DEFAULT) && (p->value == NULL))
            {
              counter = counter_old;
              max_len = max_len_old;
            }
          else
            {
              if (p->value == NULL)
                {
                  MHD__asn1_error_description_value_not_found (p,
                                                               ErrorDescription);
                  err = ASN1_VALUE_NOT_FOUND;
                  goto error;
                }
              len2 = max_len;
              err = MHD__asn1_objectid_der (p->value, der + counter, &len2);
              if (err != ASN1_SUCCESS && err != ASN1_MEM_ERROR)
                goto error;

              max_len -= len2;
              counter += len2;
            }
          move = RIGHT;
          break;
        case TYPE_TIME:
          if (p->value == NULL)
            {
              MHD__asn1_error_description_value_not_found (p,
                                                           ErrorDescription);
              err = ASN1_VALUE_NOT_FOUND;
              goto error;
            }
          len2 = max_len;
          err = MHD__asn1_time_der (p->value, der + counter, &len2);
          if (err != ASN1_SUCCESS && err != ASN1_MEM_ERROR)
            goto error;

          max_len -= len2;
          counter += len2;
          move = RIGHT;
          break;
        case TYPE_OCTET_STRING:
          if (p->value == NULL)
            {
              MHD__asn1_error_description_value_not_found (p,
                                                           ErrorDescription);
              err = ASN1_VALUE_NOT_FOUND;
              goto error;
            }
          len2 = MHD__asn1_get_length_der (p->value, p->value_len, &len3);
          if (len2 < 0)
            {
              err = ASN1_DER_ERROR;
              goto error;
            }
          max_len -= len2 + len3;
          if (max_len >= 0)
            memcpy (der + counter, p->value, len3 + len2);
          counter += len3 + len2;
          move = RIGHT;
          break;
        case TYPE_GENERALSTRING:
          if (p->value == NULL)
            {
              MHD__asn1_error_description_value_not_found (p,
                                                           ErrorDescription);
              err = ASN1_VALUE_NOT_FOUND;
              goto error;
            }
          len2 = MHD__asn1_get_length_der (p->value, p->value_len, &len3);
          if (len2 < 0)
            {
              err = ASN1_DER_ERROR;
              goto error;
            }
          max_len -= len2 + len3;
          if (max_len >= 0)
            memcpy (der + counter, p->value, len3 + len2);
          counter += len3 + len2;
          move = RIGHT;
          break;
        case TYPE_BIT_STRING:
          if (p->value == NULL)
            {
              MHD__asn1_error_description_value_not_found (p,
                                                           ErrorDescription);
              err = ASN1_VALUE_NOT_FOUND;
              goto error;
            }
          len2 = MHD__asn1_get_length_der (p->value, p->value_len, &len3);
          if (len2 < 0)
            {
              err = ASN1_DER_ERROR;
              goto error;
            }
          max_len -= len2 + len3;
          if (max_len >= 0)
            memcpy (der + counter, p->value, len3 + len2);
          counter += len3 + len2;
          move = RIGHT;
          break;
        case TYPE_SEQUENCE:
        case TYPE_SET:
          if (move != UP)
            {
              MHD__asn1_ltostr (counter, temp);
              tlen = strlen (temp);
              if (tlen > 0)
                MHD__asn1_set_value (p, temp, tlen + 1);
              if (p->down == NULL)
                {
                  move = UP;
                  continue;
                }
              else
                {
                  p2 = p->down;
                  while (p2 && (type_field (p2->type) == TYPE_TAG))
                    p2 = p2->right;
                  if (p2)
                    {
                      p = p2;
                      move = RIGHT;
                      continue;
                    }
                  move = UP;
                  continue;
                }
            }
          else
            {                   /* move==UP */
              len2 = strtol ((const char *) p->value, NULL, 10);
              MHD__asn1_set_value (p, NULL, 0);
              if ((type_field (p->type) == TYPE_SET) && (max_len >= 0))
                MHD__asn1_ordering_set (der + len2, max_len - len2, p);
              MHD__asn1_length_der (counter - len2, (unsigned char *) temp,
                                    &len3);
              max_len -= len3;
              if (max_len >= 0)
                {
                  memmove (der + len2 + len3, der + len2, counter - len2);
                  memcpy (der + len2, temp, len3);
                }
              counter += len3;
              move = RIGHT;
            }
          break;
        case TYPE_SEQUENCE_OF:
        case TYPE_SET_OF:
          if (move != UP)
            {
              MHD__asn1_ltostr (counter, temp);
              tlen = strlen (temp);

              if (tlen > 0)
                MHD__asn1_set_value (p, temp, tlen + 1);
              p = p->down;
              while ((type_field (p->type) == TYPE_TAG)
                     || (type_field (p->type) == TYPE_SIZE))
                p = p->right;
              if (p->right)
                {
                  p = p->right;
                  move = RIGHT;
                  continue;
                }
              else
                p = MHD__asn1_find_up (p);
              move = UP;
            }
          if (move == UP)
            {
              len2 = strtol ((const char *) p->value, NULL, 10);
              MHD__asn1_set_value (p, NULL, 0);
              if ((type_field (p->type) == TYPE_SET_OF)
                  && (max_len - len2 > 0))
                {
                  MHD__asn1_ordering_set_of (der + len2, max_len - len2, p);
                }
              MHD__asn1_length_der (counter - len2, (unsigned char *) temp,
                                    &len3);
              max_len -= len3;
              if (max_len >= 0)
                {
                  memmove (der + len2 + len3, der + len2, counter - len2);
                  memcpy (der + len2, temp, len3);
                }
              counter += len3;
              move = RIGHT;
            }
          break;
        case TYPE_ANY:
          if (p->value == NULL)
            {
              MHD__asn1_error_description_value_not_found (p,
                                                           ErrorDescription);
              err = ASN1_VALUE_NOT_FOUND;
              goto error;
            }
          len2 = MHD__asn1_get_length_der (p->value, p->value_len, &len3);
          if (len2 < 0)
            {
              err = ASN1_DER_ERROR;
              goto error;
            }
          max_len -= len2;
          if (max_len >= 0)
            memcpy (der + counter, p->value + len3, len2);
          counter += len2;
          move = RIGHT;
          break;
        default:
          move = (move == UP) ? RIGHT : DOWN;
          break;
        }

      if ((move != DOWN) && (counter != counter_old))
        {
          err = MHD__asn1_complete_explicit_tag (p, der, &counter, &max_len);
          if (err != ASN1_SUCCESS && err != ASN1_MEM_ERROR)
            goto error;
        }

      if (p == node && move != DOWN)
        break;

      if (move == DOWN)
        {
          if (p->down)
            p = p->down;
          else
            move = RIGHT;
        }
      if (move == RIGHT)
        {
          if (p->right)
            p = p->right;
          else
            move = UP;
        }
      if (move == UP)
        p = MHD__asn1_find_up (p);
    }

  *len = counter;

  if (max_len < 0)
    {
      err = ASN1_MEM_ERROR;
      goto error;
    }

  err = ASN1_SUCCESS;

error:
  MHD__asn1_delete_structure (&node);
  return err;
}