Fix warnings (From HEAD, original patch by Ben).
[openssl.git] / crypto / asn1 / tasn_dec.c
1 /* tasn_dec.c */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 2000-2005 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer. 
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58
59
60 #include <stddef.h>
61 #include <string.h>
62 #include <openssl/asn1.h>
63 #include <openssl/asn1t.h>
64 #include <openssl/objects.h>
65 #include <openssl/buffer.h>
66 #include <openssl/err.h>
67
68 static int asn1_check_eoc(const unsigned char **in, long len);
69 static int asn1_find_end(const unsigned char **in, long len, char inf);
70
71 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
72                         char inf, int tag, int aclass, int depth);
73
74 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
75
76 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
77                                 char *inf, char *cst,
78                                 const unsigned char **in, long len,
79                                 int exptag, int expclass, char opt,
80                                 ASN1_TLC *ctx);
81
82 static int asn1_template_ex_d2i(ASN1_VALUE **pval,
83                                 const unsigned char **in, long len,
84                                 const ASN1_TEMPLATE *tt, char opt,
85                                 ASN1_TLC *ctx);
86 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
87                                 const unsigned char **in, long len,
88                                 const ASN1_TEMPLATE *tt, char opt,
89                                 ASN1_TLC *ctx);
90 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
91                                 const unsigned char **in, long len,
92                                 const ASN1_ITEM *it,
93                                 int tag, int aclass, char opt, ASN1_TLC *ctx);
94
95 /* Table to convert tags to bit values, used for MSTRING type */
96 static const unsigned long tag2bit[32] = {
97 0,      0,      0,      B_ASN1_BIT_STRING,      /* tags  0 -  3 */
98 B_ASN1_OCTET_STRING,    0,      0,              B_ASN1_UNKNOWN,/* tags  4- 7 */
99 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags  8-11 */
100 B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
101 B_ASN1_SEQUENCE,0,B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */
102 B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
103 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,                        /* tags 23-24 */ 
104 B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
105 B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
106         };
107
108 unsigned long ASN1_tag2bit(int tag)
109         {
110         if ((tag < 0) || (tag > 30)) return 0;
111         return tag2bit[tag];
112         }
113
114 /* Macro to initialize and invalidate the cache */
115
116 #define asn1_tlc_clear(c)       if (c) (c)->valid = 0
117 /* Version to avoid compiler warning about 'c' always non-NULL */
118 #define asn1_tlc_clear_nc(c)    (c)->valid = 0
119
120 /* Decode an ASN1 item, this currently behaves just 
121  * like a standard 'd2i' function. 'in' points to 
122  * a buffer to read the data from, in future we will
123  * have more advanced versions that can input data
124  * a piece at a time and this will simply be a special
125  * case.
126  */
127
128 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
129                 const unsigned char **in, long len, const ASN1_ITEM *it)
130         {
131         ASN1_TLC c;
132         ASN1_VALUE *ptmpval = NULL;
133         if (!pval)
134                 pval = &ptmpval;
135         asn1_tlc_clear_nc(&c);
136         if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0) 
137                 return *pval;
138         return NULL;
139         }
140
141 int ASN1_template_d2i(ASN1_VALUE **pval,
142                 const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
143         {
144         ASN1_TLC c;
145         asn1_tlc_clear_nc(&c);
146         return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
147         }
148
149
150 /* Decode an item, taking care of IMPLICIT tagging, if any.
151  * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
152  */
153
154 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
155                         const ASN1_ITEM *it,
156                         int tag, int aclass, char opt, ASN1_TLC *ctx)
157         {
158         const ASN1_TEMPLATE *tt, *errtt = NULL;
159         const ASN1_COMPAT_FUNCS *cf;
160         const ASN1_EXTERN_FUNCS *ef;
161         const ASN1_AUX *aux = it->funcs;
162         ASN1_aux_cb *asn1_cb;
163         const unsigned char *p = NULL, *q;
164         unsigned char *wp=NULL; /* BIG FAT WARNING!  BREAKS CONST WHERE USED */
165         unsigned char imphack = 0, oclass;
166         char seq_eoc, seq_nolen, cst, isopt;
167         long tmplen;
168         int i;
169         int otag;
170         int ret = 0;
171         ASN1_VALUE **pchptr, *ptmpval;
172         if (!pval)
173                 return 0;
174         if (aux && aux->asn1_cb)
175                 asn1_cb = aux->asn1_cb;
176         else asn1_cb = 0;
177
178         switch(it->itype)
179                 {
180                 case ASN1_ITYPE_PRIMITIVE:
181                 if (it->templates)
182                         {
183                         /* tagging or OPTIONAL is currently illegal on an item
184                          * template because the flags can't get passed down.
185                          * In practice this isn't a problem: we include the
186                          * relevant flags from the item template in the
187                          * template itself.
188                          */
189                         if ((tag != -1) || opt)
190                                 {
191                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
192                                 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
193                                 goto err;
194                                 }
195                         return asn1_template_ex_d2i(pval, in, len,
196                                         it->templates, opt, ctx);
197                 }
198                 return asn1_d2i_ex_primitive(pval, in, len, it,
199                                                 tag, aclass, opt, ctx);
200                 break;
201
202                 case ASN1_ITYPE_MSTRING:
203                 p = *in;
204                 /* Just read in tag and class */
205                 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
206                                                 &p, len, -1, 0, 1, ctx);
207                 if (!ret)
208                         {
209                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
210                                         ERR_R_NESTED_ASN1_ERROR);
211                         goto err;
212                         }
213
214                 /* Must be UNIVERSAL class */
215                 if (oclass != V_ASN1_UNIVERSAL)
216                         {
217                         /* If OPTIONAL, assume this is OK */
218                         if (opt) return -1;
219                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
220                                         ASN1_R_MSTRING_NOT_UNIVERSAL);
221                         goto err;
222                         }
223                 /* Check tag matches bit map */
224                 if (!(ASN1_tag2bit(otag) & it->utype))
225                         {
226                         /* If OPTIONAL, assume this is OK */
227                         if (opt)
228                                 return -1;
229                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
230                                         ASN1_R_MSTRING_WRONG_TAG);
231                         goto err;
232                         }
233                 return asn1_d2i_ex_primitive(pval, in, len,
234                                                 it, otag, 0, 0, ctx);
235
236                 case ASN1_ITYPE_EXTERN:
237                 /* Use new style d2i */
238                 ef = it->funcs;
239                 return ef->asn1_ex_d2i(pval, in, len,
240                                                 it, tag, aclass, opt, ctx);
241
242                 case ASN1_ITYPE_COMPAT:
243                 /* we must resort to old style evil hackery */
244                 cf = it->funcs;
245
246                 /* If OPTIONAL see if it is there */
247                 if (opt)
248                         {
249                         int exptag;
250                         p = *in;
251                         if (tag == -1)
252                                 exptag = it->utype;
253                         else exptag = tag;
254                         /* Don't care about anything other than presence
255                          * of expected tag */
256
257                         ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
258                                         &p, len, exptag, aclass, 1, ctx);
259                         if (!ret)
260                                 {
261                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
262                                         ERR_R_NESTED_ASN1_ERROR);
263                                 goto err;
264                                 }
265                         if (ret == -1)
266                                 return -1;
267                         }
268
269                 /* This is the old style evil hack IMPLICIT handling:
270                  * since the underlying code is expecting a tag and
271                  * class other than the one present we change the
272                  * buffer temporarily then change it back afterwards.
273                  * This doesn't and never did work for tags > 30.
274                  *
275                  * Yes this is *horrible* but it is only needed for
276                  * old style d2i which will hopefully not be around
277                  * for much longer.
278                  * FIXME: should copy the buffer then modify it so
279                  * the input buffer can be const: we should *always*
280                  * copy because the old style d2i might modify the
281                  * buffer.
282                  */
283
284                 if (tag != -1)
285                         {
286                         wp = *(unsigned char **)in;
287                         imphack = *wp;
288                         if (p == NULL)
289                                 {
290                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
291                                         ERR_R_NESTED_ASN1_ERROR);
292                                 goto err;
293                                 }
294                         *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
295                                                                 | it->utype);
296                         }
297
298                 ptmpval = cf->asn1_d2i(pval, in, len);
299
300                 if (tag != -1)
301                         *wp = imphack;
302
303                 if (ptmpval)
304                         return 1;
305
306                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
307                 goto err;
308
309
310                 case ASN1_ITYPE_CHOICE:
311                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
312                                 goto auxerr;
313
314                 /* Allocate structure */
315                 if (!*pval && !ASN1_item_ex_new(pval, it))
316                         {
317                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
318                                                 ERR_R_NESTED_ASN1_ERROR);
319                         goto err;
320                         }
321                 /* CHOICE type, try each possibility in turn */
322                 p = *in;
323                 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
324                         {
325                         pchptr = asn1_get_field_ptr(pval, tt);
326                         /* We mark field as OPTIONAL so its absence
327                          * can be recognised.
328                          */
329                         ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
330                         /* If field not present, try the next one */
331                         if (ret == -1)
332                                 continue;
333                         /* If positive return, read OK, break loop */
334                         if (ret > 0)
335                                 break;
336                         /* Otherwise must be an ASN1 parsing error */
337                         errtt = tt;
338                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
339                                                 ERR_R_NESTED_ASN1_ERROR);
340                         goto err;
341                         }
342
343                 /* Did we fall off the end without reading anything? */
344                 if (i == it->tcount)
345                         {
346                         /* If OPTIONAL, this is OK */
347                         if (opt)
348                                 {
349                                 /* Free and zero it */
350                                 ASN1_item_ex_free(pval, it);
351                                 return -1;
352                                 }
353                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
354                                         ASN1_R_NO_MATCHING_CHOICE_TYPE);
355                         goto err;
356                         }
357
358                 asn1_set_choice_selector(pval, i, it);
359                 *in = p;
360                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
361                                 goto auxerr;
362                 return 1;
363
364                 case ASN1_ITYPE_NDEF_SEQUENCE:
365                 case ASN1_ITYPE_SEQUENCE:
366                 p = *in;
367                 tmplen = len;
368
369                 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
370                 if (tag == -1)
371                         {
372                         tag = V_ASN1_SEQUENCE;
373                         aclass = V_ASN1_UNIVERSAL;
374                         }
375                 /* Get SEQUENCE length and update len, p */
376                 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
377                                         &p, len, tag, aclass, opt, ctx);
378                 if (!ret)
379                         {
380                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
381                                         ERR_R_NESTED_ASN1_ERROR);
382                         goto err;
383                         }
384                 else if (ret == -1)
385                         return -1;
386                 if (aux && (aux->flags & ASN1_AFLG_BROKEN))
387                         {
388                         len = tmplen - (p - *in);
389                         seq_nolen = 1;
390                         }
391                 /* If indefinite we don't do a length check */
392                 else seq_nolen = seq_eoc;
393                 if (!cst)
394                         {
395                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
396                                 ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
397                         goto err;
398                         }
399
400                 if (!*pval && !ASN1_item_ex_new(pval, it))
401                         {
402                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
403                                 ERR_R_NESTED_ASN1_ERROR);
404                         goto err;
405                         }
406
407                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
408                                 goto auxerr;
409
410                 /* Get each field entry */
411                 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
412                         {
413                         const ASN1_TEMPLATE *seqtt;
414                         ASN1_VALUE **pseqval;
415                         seqtt = asn1_do_adb(pval, tt, 1);
416                         if (!seqtt)
417                                 goto err;
418                         pseqval = asn1_get_field_ptr(pval, seqtt);
419                         /* Have we ran out of data? */
420                         if (!len)
421                                 break;
422                         q = p;
423                         if (asn1_check_eoc(&p, len))
424                                 {
425                                 if (!seq_eoc)
426                                         {
427                                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
428                                                         ASN1_R_UNEXPECTED_EOC);
429                                         goto err;
430                                         }
431                                 len -= p - q;
432                                 seq_eoc = 0;
433                                 q = p;
434                                 break;
435                                 }
436                         /* This determines the OPTIONAL flag value. The field
437                          * cannot be omitted if it is the last of a SEQUENCE
438                          * and there is still data to be read. This isn't
439                          * strictly necessary but it increases efficiency in
440                          * some cases.
441                          */
442                         if (i == (it->tcount - 1))
443                                 isopt = 0;
444                         else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
445                         /* attempt to read in field, allowing each to be
446                          * OPTIONAL */
447
448                         ret = asn1_template_ex_d2i(pseqval, &p, len,
449                                                         seqtt, isopt, ctx);
450                         if (!ret)
451                                 {
452                                 errtt = seqtt;
453                                 goto err;
454                                 }
455                         else if (ret == -1)
456                                 {
457                                 /* OPTIONAL component absent.
458                                  * Free and zero the field.
459                                  */
460                                 ASN1_template_free(pseqval, seqtt);
461                                 continue;
462                                 }
463                         /* Update length */
464                         len -= p - q;
465                         }
466
467                 /* Check for EOC if expecting one */
468                 if (seq_eoc && !asn1_check_eoc(&p, len))
469                         {
470                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
471                         goto err;
472                         }
473                 /* Check all data read */
474                 if (!seq_nolen && len)
475                         {
476                         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
477                                         ASN1_R_SEQUENCE_LENGTH_MISMATCH);
478                         goto err;
479                         }
480
481                 /* If we get here we've got no more data in the SEQUENCE,
482                  * however we may not have read all fields so check all
483                  * remaining are OPTIONAL and clear any that are.
484                  */
485                 for (; i < it->tcount; tt++, i++)
486                         {
487                         const ASN1_TEMPLATE *seqtt;
488                         seqtt = asn1_do_adb(pval, tt, 1);
489                         if (!seqtt)
490                                 goto err;
491                         if (seqtt->flags & ASN1_TFLG_OPTIONAL)
492                                 {
493                                 ASN1_VALUE **pseqval;
494                                 pseqval = asn1_get_field_ptr(pval, seqtt);
495                                 ASN1_template_free(pseqval, seqtt);
496                                 }
497                         else
498                                 {
499                                 errtt = seqtt;
500                                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
501                                                         ASN1_R_FIELD_MISSING);
502                                 goto err;
503                                 }
504                         }
505                 /* Save encoding */
506                 if (!asn1_enc_save(pval, *in, p - *in, it))
507                         goto auxerr;
508                 *in = p;
509                 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
510                                 goto auxerr;
511                 return 1;
512
513                 default:
514                 return 0;
515                 }
516         auxerr:
517         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
518         err:
519         ASN1_item_ex_free(pval, it);
520         if (errtt)
521                 ERR_add_error_data(4, "Field=", errtt->field_name,
522                                         ", Type=", it->sname);
523         else
524                 ERR_add_error_data(2, "Type=", it->sname);
525         return 0;
526         }
527
528 /* Templates are handled with two separate functions.
529  * One handles any EXPLICIT tag and the other handles the rest.
530  */
531
532 static int asn1_template_ex_d2i(ASN1_VALUE **val,
533                                 const unsigned char **in, long inlen,
534                                 const ASN1_TEMPLATE *tt, char opt,
535                                                         ASN1_TLC *ctx)
536         {
537         int flags, aclass;
538         int ret;
539         long len;
540         const unsigned char *p, *q;
541         char exp_eoc;
542         if (!val)
543                 return 0;
544         flags = tt->flags;
545         aclass = flags & ASN1_TFLG_TAG_CLASS;
546
547         p = *in;
548
549         /* Check if EXPLICIT tag expected */
550         if (flags & ASN1_TFLG_EXPTAG)
551                 {
552                 char cst;
553                 /* Need to work out amount of data available to the inner
554                  * content and where it starts: so read in EXPLICIT header to
555                  * get the info.
556                  */
557                 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
558                                         &p, inlen, tt->tag, aclass, opt, ctx);
559                 q = p;
560                 if (!ret)
561                         {
562                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
563                                         ERR_R_NESTED_ASN1_ERROR);
564                         return 0;
565                         }
566                 else if (ret == -1)
567                         return -1;
568                 if (!cst)
569                         {
570                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
571                                         ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
572                         return 0;
573                         }
574                 /* We've found the field so it can't be OPTIONAL now */
575                 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
576                 if (!ret)
577                         {
578                         ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
579                                         ERR_R_NESTED_ASN1_ERROR);
580                         return 0;
581                         }
582                 /* We read the field in OK so update length */
583                 len -= p - q;
584                 if (exp_eoc)
585                         {
586                         /* If NDEF we must have an EOC here */
587                         if (!asn1_check_eoc(&p, len))
588                                 {
589                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
590                                                 ASN1_R_MISSING_EOC);
591                                 goto err;
592                                 }
593                         }
594                 else
595                         {
596                         /* Otherwise we must hit the EXPLICIT tag end or its
597                          * an error */
598                         if (len)
599                                 {
600                                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
601                                         ASN1_R_EXPLICIT_LENGTH_MISMATCH);
602                                 goto err;
603                                 }
604                         }
605                 }
606                 else 
607                         return asn1_template_noexp_d2i(val, in, inlen,
608                                                                 tt, opt, ctx);
609
610         *in = p;
611         return 1;
612
613         err:
614         ASN1_template_free(val, tt);
615         return 0;
616         }
617
618 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
619                                 const unsigned char **in, long len,
620                                 const ASN1_TEMPLATE *tt, char opt,
621                                 ASN1_TLC *ctx)
622         {
623         int flags, aclass;
624         int ret;
625         const unsigned char *p, *q;
626         if (!val)
627                 return 0;
628         flags = tt->flags;
629         aclass = flags & ASN1_TFLG_TAG_CLASS;
630
631         p = *in;
632         q = p;
633
634         if (flags & ASN1_TFLG_SK_MASK)
635                 {
636                 /* SET OF, SEQUENCE OF */
637                 int sktag, skaclass;
638                 char sk_eoc;
639                 /* First work out expected inner tag value */
640                 if (flags & ASN1_TFLG_IMPTAG)
641                         {
642                         sktag = tt->tag;
643                         skaclass = aclass;
644                         }
645                 else
646                         {
647                         skaclass = V_ASN1_UNIVERSAL;
648                         if (flags & ASN1_TFLG_SET_OF)
649                                 sktag = V_ASN1_SET;
650                         else
651                                 sktag = V_ASN1_SEQUENCE;
652                         }
653                 /* Get the tag */
654                 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
655                                         &p, len, sktag, skaclass, opt, ctx);
656                 if (!ret)
657                         {
658                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
659                                                 ERR_R_NESTED_ASN1_ERROR);
660                         return 0;
661                         }
662                 else if (ret == -1)
663                         return -1;
664                 if (!*val)
665                         *val = (ASN1_VALUE *)sk_new_null();
666                 else
667                         {
668                         /* We've got a valid STACK: free up any items present */
669                         STACK_OF(ASN1_VALUE) *sktmp
670                             = (STACK_OF(ASN1_VALUE) *)*val;
671                         ASN1_VALUE *vtmp;
672                         while(sk_ASN1_VALUE_num(sktmp) > 0)
673                                 {
674                                 vtmp = sk_ASN1_VALUE_pop(sktmp);
675                                 ASN1_item_ex_free(&vtmp,
676                                                 ASN1_ITEM_ptr(tt->item));
677                                 }
678                         }
679                                 
680                 if (!*val)
681                         {
682                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
683                                                 ERR_R_MALLOC_FAILURE);
684                         goto err;
685                         }
686
687                 /* Read as many items as we can */
688                 while(len > 0)
689                         {
690                         ASN1_VALUE *skfield;
691                         q = p;
692                         /* See if EOC found */
693                         if (asn1_check_eoc(&p, len))
694                                 {
695                                 if (!sk_eoc)
696                                         {
697                                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
698                                                         ASN1_R_UNEXPECTED_EOC);
699                                         goto err;
700                                         }
701                                 len -= p - q;
702                                 sk_eoc = 0;
703                                 break;
704                                 }
705                         skfield = NULL;
706                         if (!ASN1_item_ex_d2i(&skfield, &p, len,
707                                                 ASN1_ITEM_ptr(tt->item),
708                                                 -1, 0, 0, ctx))
709                                 {
710                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
711                                         ERR_R_NESTED_ASN1_ERROR);
712                                 goto err;
713                                 }
714                         len -= p - q;
715                         if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val,
716                                                 skfield))
717                                 {
718                                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
719                                                 ERR_R_MALLOC_FAILURE);
720                                 goto err;
721                                 }
722                         }
723                 if (sk_eoc)
724                         {
725                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
726                         goto err;
727                         }
728                 }
729         else if (flags & ASN1_TFLG_IMPTAG)
730                 {
731                 /* IMPLICIT tagging */
732                 ret = ASN1_item_ex_d2i(val, &p, len,
733                         ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
734                 if (!ret)
735                         {
736                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
737                                                 ERR_R_NESTED_ASN1_ERROR);
738                         goto err;
739                         }
740                 else if (ret == -1)
741                         return -1;
742                 }
743         else
744                 {
745                 /* Nothing special */
746                 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
747                                                         -1, 0, opt, ctx);
748                 if (!ret)
749                         {
750                         ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
751                                         ERR_R_NESTED_ASN1_ERROR);
752                         goto err;
753                         }
754                 else if (ret == -1)
755                         return -1;
756                 }
757
758         *in = p;
759         return 1;
760
761         err:
762         ASN1_template_free(val, tt);
763         return 0;
764         }
765
766 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
767                                 const unsigned char **in, long inlen, 
768                                 const ASN1_ITEM *it,
769                                 int tag, int aclass, char opt, ASN1_TLC *ctx)
770         {
771         int ret = 0, utype;
772         long plen;
773         char cst, inf, free_cont = 0;
774         const unsigned char *p;
775         BUF_MEM buf;
776         const unsigned char *cont = NULL;
777         long len; 
778         if (!pval)
779                 {
780                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
781                 return 0; /* Should never happen */
782                 }
783
784         if (it->itype == ASN1_ITYPE_MSTRING)
785                 {
786                 utype = tag;
787                 tag = -1;
788                 }
789         else
790                 utype = it->utype;
791
792         if (utype == V_ASN1_ANY)
793                 {
794                 /* If type is ANY need to figure out type from tag */
795                 unsigned char oclass;
796                 if (tag >= 0)
797                         {
798                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
799                                         ASN1_R_ILLEGAL_TAGGED_ANY);
800                         return 0;
801                         }
802                 if (opt)
803                         {
804                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
805                                         ASN1_R_ILLEGAL_OPTIONAL_ANY);
806                         return 0;
807                         }
808                 p = *in;
809                 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
810                                         &p, inlen, -1, 0, 0, ctx);
811                 if (!ret)
812                         {
813                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
814                                         ERR_R_NESTED_ASN1_ERROR);
815                         return 0;
816                         }
817                 if (oclass != V_ASN1_UNIVERSAL)
818                         utype = V_ASN1_OTHER;
819                 }
820         if (tag == -1)
821                 {
822                 tag = utype;
823                 aclass = V_ASN1_UNIVERSAL;
824                 }
825         p = *in;
826         /* Check header */
827         ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
828                                 &p, inlen, tag, aclass, opt, ctx);
829         if (!ret)
830                 {
831                 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
832                 return 0;
833                 }
834         else if (ret == -1)
835                 return -1;
836         ret = 0;
837         /* SEQUENCE, SET and "OTHER" are left in encoded form */
838         if ((utype == V_ASN1_SEQUENCE)
839                 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
840                 {
841                 /* Clear context cache for type OTHER because the auto clear
842                  * when we have a exact match wont work
843                  */
844                 if (utype == V_ASN1_OTHER)
845                         {
846                         asn1_tlc_clear(ctx);
847                         }
848                 /* SEQUENCE and SET must be constructed */
849                 else if (!cst)
850                         {
851                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
852                                 ASN1_R_TYPE_NOT_CONSTRUCTED);
853                         return 0;
854                         }
855
856                 cont = *in;
857                 /* If indefinite length constructed find the real end */
858                 if (inf)
859                         {
860                         if (!asn1_find_end(&p, plen, inf))
861                                  goto err;
862                         len = p - cont;
863                         }
864                 else
865                         {
866                         len = p - cont + plen;
867                         p += plen;
868                         buf.data = NULL;
869                         }
870                 }
871         else if (cst)
872                 {
873                 buf.length = 0;
874                 buf.max = 0;
875                 buf.data = NULL;
876                 /* Should really check the internal tags are correct but
877                  * some things may get this wrong. The relevant specs
878                  * say that constructed string types should be OCTET STRINGs
879                  * internally irrespective of the type. So instead just check
880                  * for UNIVERSAL class and ignore the tag.
881                  */
882                 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
883                         {
884                         free_cont = 1;
885                         goto err;
886                         }
887                 len = buf.length;
888                 /* Append a final null to string */
889                 if (!BUF_MEM_grow_clean(&buf, len + 1))
890                         {
891                         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
892                                                 ERR_R_MALLOC_FAILURE);
893                         return 0;
894                         }
895                 buf.data[len] = 0;
896                 cont = (const unsigned char *)buf.data;
897                 free_cont = 1;
898                 }
899         else
900                 {
901                 cont = p;
902                 len = plen;
903                 p += plen;
904                 }
905
906         /* We now have content length and type: translate into a structure */
907         if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
908                 goto err;
909
910         *in = p;
911         ret = 1;
912         err:
913         if (free_cont && buf.data) OPENSSL_free(buf.data);
914         return ret;
915         }
916
917 /* Translate ASN1 content octets into a structure */
918
919 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
920                         int utype, char *free_cont, const ASN1_ITEM *it)
921         {
922         ASN1_VALUE **opval = NULL;
923         ASN1_STRING *stmp;
924         ASN1_TYPE *typ = NULL;
925         int ret = 0;
926         const ASN1_PRIMITIVE_FUNCS *pf;
927         ASN1_INTEGER **tint;
928         pf = it->funcs;
929
930         if (pf && pf->prim_c2i)
931                 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
932         /* If ANY type clear type and set pointer to internal value */
933         if (it->utype == V_ASN1_ANY)
934                 {
935                 if (!*pval)
936                         {
937                         typ = ASN1_TYPE_new();
938                         if (typ == NULL)
939                                 goto err;
940                         *pval = (ASN1_VALUE *)typ;
941                         }
942                 else
943                         typ = (ASN1_TYPE *)*pval;
944
945                 if (utype != typ->type)
946                         ASN1_TYPE_set(typ, utype, NULL);
947                 opval = pval;
948                 pval = &typ->value.asn1_value;
949                 }
950         switch(utype)
951                 {
952                 case V_ASN1_OBJECT:
953                 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
954                         goto err;
955                 break;
956
957                 case V_ASN1_NULL:
958                 if (len)
959                         {
960                         ASN1err(ASN1_F_ASN1_EX_C2I,
961                                                 ASN1_R_NULL_IS_WRONG_LENGTH);
962                         goto err;
963                         }
964                 *pval = (ASN1_VALUE *)1;
965                 break;
966
967                 case V_ASN1_BOOLEAN:
968                 if (len != 1)
969                         {
970                         ASN1err(ASN1_F_ASN1_EX_C2I,
971                                                 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
972                         goto err;
973                         }
974                 else
975                         {
976                         ASN1_BOOLEAN *tbool;
977                         tbool = (ASN1_BOOLEAN *)pval;
978                         *tbool = *cont;
979                         }
980                 break;
981
982                 case V_ASN1_BIT_STRING:
983                 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
984                         goto err;
985                 break;
986
987                 case V_ASN1_INTEGER:
988                 case V_ASN1_NEG_INTEGER:
989                 case V_ASN1_ENUMERATED:
990                 case V_ASN1_NEG_ENUMERATED:
991                 tint = (ASN1_INTEGER **)pval;
992                 if (!c2i_ASN1_INTEGER(tint, &cont, len))
993                         goto err;
994                 /* Fixup type to match the expected form */
995                 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
996                 break;
997
998                 case V_ASN1_OCTET_STRING:
999                 case V_ASN1_NUMERICSTRING:
1000                 case V_ASN1_PRINTABLESTRING:
1001                 case V_ASN1_T61STRING:
1002                 case V_ASN1_VIDEOTEXSTRING:
1003                 case V_ASN1_IA5STRING:
1004                 case V_ASN1_UTCTIME:
1005                 case V_ASN1_GENERALIZEDTIME:
1006                 case V_ASN1_GRAPHICSTRING:
1007                 case V_ASN1_VISIBLESTRING:
1008                 case V_ASN1_GENERALSTRING:
1009                 case V_ASN1_UNIVERSALSTRING:
1010                 case V_ASN1_BMPSTRING:
1011                 case V_ASN1_UTF8STRING:
1012                 case V_ASN1_OTHER:
1013                 case V_ASN1_SET:
1014                 case V_ASN1_SEQUENCE:
1015                 default:
1016                 if (utype == V_ASN1_BMPSTRING && (len & 1))
1017                         {
1018                         ASN1err(ASN1_F_ASN1_EX_C2I,
1019                                         ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
1020                         goto err;
1021                         }
1022                 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
1023                         {
1024                         ASN1err(ASN1_F_ASN1_EX_C2I,
1025                                         ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
1026                         goto err;
1027                         }
1028                 /* All based on ASN1_STRING and handled the same */
1029                 if (!*pval)
1030                         {
1031                         stmp = ASN1_STRING_type_new(utype);
1032                         if (!stmp)
1033                                 {
1034                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1035                                                         ERR_R_MALLOC_FAILURE);
1036                                 goto err;
1037                                 }
1038                         *pval = (ASN1_VALUE *)stmp;
1039                         }
1040                 else
1041                         {
1042                         stmp = (ASN1_STRING *)*pval;
1043                         stmp->type = utype;
1044                         }
1045                 /* If we've already allocated a buffer use it */
1046                 if (*free_cont)
1047                         {
1048                         if (stmp->data)
1049                                 OPENSSL_free(stmp->data);
1050                         stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1051                         stmp->length = len;
1052                         *free_cont = 0;
1053                         }
1054                 else
1055                         {
1056                         if (!ASN1_STRING_set(stmp, cont, len))
1057                                 {
1058                                 ASN1err(ASN1_F_ASN1_EX_C2I,
1059                                                         ERR_R_MALLOC_FAILURE);
1060                                 ASN1_STRING_free(stmp); 
1061                                 *pval = NULL;
1062                                 goto err;
1063                                 }
1064                         }
1065                 break;
1066                 }
1067         /* If ASN1_ANY and NULL type fix up value */
1068         if (typ && (utype == V_ASN1_NULL))
1069                  typ->value.ptr = NULL;
1070
1071         ret = 1;
1072         err:
1073         if (!ret)
1074                 {
1075                 ASN1_TYPE_free(typ);
1076                 if (opval)
1077                         *opval = NULL;
1078                 }
1079         return ret;
1080         }
1081
1082
1083 /* This function finds the end of an ASN1 structure when passed its maximum
1084  * length, whether it is indefinite length and a pointer to the content.
1085  * This is more efficient than calling asn1_collect because it does not
1086  * recurse on each indefinite length header.
1087  */
1088
1089 static int asn1_find_end(const unsigned char **in, long len, char inf)
1090         {
1091         int expected_eoc;
1092         long plen;
1093         const unsigned char *p = *in, *q;
1094         /* If not indefinite length constructed just add length */
1095         if (inf == 0)
1096                 {
1097                 *in += len;
1098                 return 1;
1099                 }
1100         expected_eoc = 1;
1101         /* Indefinite length constructed form. Find the end when enough EOCs
1102          * are found. If more indefinite length constructed headers
1103          * are encountered increment the expected eoc count otherwise just
1104          * skip to the end of the data.
1105          */
1106         while (len > 0)
1107                 {
1108                 if(asn1_check_eoc(&p, len))
1109                         {
1110                         expected_eoc--;
1111                         if (expected_eoc == 0)
1112                                 break;
1113                         len -= 2;
1114                         continue;
1115                         }
1116                 q = p;
1117                 /* Just read in a header: only care about the length */
1118                 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1119                                 -1, 0, 0, NULL))
1120                         {
1121                         ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1122                         return 0;
1123                         }
1124                 if (inf)
1125                         expected_eoc++;
1126                 else
1127                         p += plen;
1128                 len -= p - q;
1129                 }
1130         if (expected_eoc)
1131                 {
1132                 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1133                 return 0;
1134                 }
1135         *in = p;
1136         return 1;
1137         }
1138 /* This function collects the asn1 data from a constructred string
1139  * type into a buffer. The values of 'in' and 'len' should refer
1140  * to the contents of the constructed type and 'inf' should be set
1141  * if it is indefinite length.
1142  */
1143
1144 #ifndef ASN1_MAX_STRING_NEST
1145 /* This determines how many levels of recursion are permitted in ASN1
1146  * string types. If it is not limited stack overflows can occur. If set
1147  * to zero no recursion is allowed at all. Although zero should be adequate
1148  * examples exist that require a value of 1. So 5 should be more than enough.
1149  */
1150 #define ASN1_MAX_STRING_NEST 5
1151 #endif
1152
1153
1154 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1155                         char inf, int tag, int aclass, int depth)
1156         {
1157         const unsigned char *p, *q;
1158         long plen;
1159         char cst, ininf;
1160         p = *in;
1161         inf &= 1;
1162         /* If no buffer and not indefinite length constructed just pass over
1163          * the encoded data */
1164         if (!buf && !inf)
1165                 {
1166                 *in += len;
1167                 return 1;
1168                 }
1169         while(len > 0)
1170                 {
1171                 q = p;
1172                 /* Check for EOC */
1173                 if (asn1_check_eoc(&p, len))
1174                         {
1175                         /* EOC is illegal outside indefinite length
1176                          * constructed form */
1177                         if (!inf)
1178                                 {
1179                                 ASN1err(ASN1_F_ASN1_COLLECT,
1180                                         ASN1_R_UNEXPECTED_EOC);
1181                                 return 0;
1182                                 }
1183                         inf = 0;
1184                         break;
1185                         }
1186
1187                 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1188                                         len, tag, aclass, 0, NULL))
1189                         {
1190                         ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1191                         return 0;
1192                         }
1193
1194                 /* If indefinite length constructed update max length */
1195                 if (cst)
1196                         {
1197                         if (depth >= ASN1_MAX_STRING_NEST)
1198                                 {
1199                                 ASN1err(ASN1_F_ASN1_COLLECT,
1200                                         ASN1_R_NESTED_ASN1_STRING);
1201                                 return 0;
1202                                 }
1203                         if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
1204                                                 depth + 1))
1205                                 return 0;
1206                         }
1207                 else if (plen && !collect_data(buf, &p, plen))
1208                         return 0;
1209                 len -= p - q;
1210                 }
1211         if (inf)
1212                 {
1213                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1214                 return 0;
1215                 }
1216         *in = p;
1217         return 1;
1218         }
1219
1220 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1221         {
1222         int len;
1223         if (buf)
1224                 {
1225                 len = buf->length;
1226                 if (!BUF_MEM_grow_clean(buf, len + plen))
1227                         {
1228                         ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1229                         return 0;
1230                         }
1231                 memcpy(buf->data + len, *p, plen);
1232                 }
1233         *p += plen;
1234         return 1;
1235         }
1236
1237 /* Check for ASN1 EOC and swallow it if found */
1238
1239 static int asn1_check_eoc(const unsigned char **in, long len)
1240         {
1241         const unsigned char *p;
1242         if (len < 2) return 0;
1243         p = *in;
1244         if (!p[0] && !p[1])
1245                 {
1246                 *in += 2;
1247                 return 1;
1248                 }
1249         return 0;
1250         }
1251
1252 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1253  * but it sets the length for indefinite length constructed
1254  * form, we don't know the exact length but we can set an
1255  * upper bound to the amount of data available minus the
1256  * header length just read.
1257  */
1258
1259 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1260                                 char *inf, char *cst,
1261                                 const unsigned char **in, long len,
1262                                 int exptag, int expclass, char opt,
1263                                 ASN1_TLC *ctx)
1264         {
1265         int i;
1266         int ptag, pclass;
1267         long plen;
1268         const unsigned char *p, *q;
1269         p = *in;
1270         q = p;
1271
1272         if (ctx && ctx->valid)
1273                 {
1274                 i = ctx->ret;
1275                 plen = ctx->plen;
1276                 pclass = ctx->pclass;
1277                 ptag = ctx->ptag;
1278                 p += ctx->hdrlen;
1279                 }
1280         else
1281                 {
1282                 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1283                 if (ctx)
1284                         {
1285                         ctx->ret = i;
1286                         ctx->plen = plen;
1287                         ctx->pclass = pclass;
1288                         ctx->ptag = ptag;
1289                         ctx->hdrlen = p - q;
1290                         ctx->valid = 1;
1291                         /* If definite length, and no error, length +
1292                          * header can't exceed total amount of data available. 
1293                          */
1294                         if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1295                                 {
1296                                 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1297                                                         ASN1_R_TOO_LONG);
1298                                 asn1_tlc_clear(ctx);
1299                                 return 0;
1300                                 }
1301                         }
1302                 }
1303
1304         if (i & 0x80)
1305                 {
1306                 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1307                 asn1_tlc_clear(ctx);
1308                 return 0;
1309                 }
1310         if (exptag >= 0)
1311                 {
1312                 if ((exptag != ptag) || (expclass != pclass))
1313                         {
1314                         /* If type is OPTIONAL, not an error:
1315                          * indicate missing type.
1316                          */
1317                         if (opt) return -1;
1318                         asn1_tlc_clear(ctx);
1319                         ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1320                         return 0;
1321                         }
1322                 /* We have a tag and class match:
1323                  * assume we are going to do something with it */
1324                 asn1_tlc_clear(ctx);
1325                 }
1326
1327         if (i & 1)
1328                 plen = len - (p - q);
1329
1330         if (inf)
1331                 *inf = i & 1;
1332
1333         if (cst)
1334                 *cst = i & V_ASN1_CONSTRUCTED;
1335
1336         if (olen)
1337                 *olen = plen;
1338
1339         if (oclass)
1340                 *oclass = pclass;
1341
1342         if (otag)
1343                 *otag = ptag;
1344
1345         *in = p;
1346         return 1;
1347         }