1 /* tasn_dec.c */
2 /*
3  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
4  * 2000.
5  */
6 /* ====================================================================
7  * Copyright (c) 2000-2005 The OpenSSL Project.  All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in
18  *    the documentation and/or other materials provided with the
19  *    distribution.
20  *
21  * 3. All advertising materials mentioning features or use of this
22  *    software must display the following acknowledgment:
23  *    "This product includes software developed by the OpenSSL Project
24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25  *
26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27  *    endorse or promote products derived from this software without
28  *    prior written permission. For written permission, please contact
29  *    licensing@OpenSSL.org.
30  *
31  * 5. Products derived from this software may not be called "OpenSSL"
32  *    nor may "OpenSSL" appear in their names without prior written
33  *    permission of the OpenSSL Project.
34  *
35  * 6. Redistributions of any form whatsoever must retain the following
36  *    acknowledgment:
37  *    "This product includes software developed by the OpenSSL Project
38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51  * OF THE POSSIBILITY OF SUCH DAMAGE.
52  * ====================================================================
53  *
54  * This product includes cryptographic software written by Eric Young
55  * (eay@cryptsoft.com).  This product includes software written by Tim
56  * Hudson (tjh@cryptsoft.com).
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, ASN1_TLC *ctx);
80 
81 static int asn1_template_ex_d2i(ASN1_VALUE **pval,
82                                 const unsigned char **in, long len,
83                                 const ASN1_TEMPLATE *tt, char opt,
84                                 ASN1_TLC *ctx);
85 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
86                                    const unsigned char **in, long len,
87                                    const ASN1_TEMPLATE *tt, char opt,
88                                    ASN1_TLC *ctx);
89 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
90                                  const unsigned char **in, long len,
91                                  const ASN1_ITEM *it,
92                                  int tag, int aclass, char opt,
93                                  ASN1_TLC *ctx);
94 
95 /* Table to convert tags to bit values, used for MSTRING type */
96 static const unsigned long tag2bit[32] = {
97     /* tags  0 -  3 */
98     0, 0, 0, B_ASN1_BIT_STRING,
99     /* tags  4- 7 */
100     B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,
101     /* tags  8-11 */
102     B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
103     /* tags 12-15 */
104     B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
105     /* tags 16-19 */
106     B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING,
107     /* tags 20-22 */
108     B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING,
109     /* tags 23-24 */
110     B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,
111     /* tags 25-27 */
112     B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING,
113     /* tags 28-31 */
114     B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN,
115 };
116 
ASN1_tag2bit(int tag)117 unsigned long ASN1_tag2bit(int tag)
118 {
119     if ((tag < 0) || (tag > 30))
120         return 0;
121     return tag2bit[tag];
122 }
123 
124 /* Macro to initialize and invalidate the cache */
125 
126 #define asn1_tlc_clear(c)       if (c) (c)->valid = 0
127 
128 /*
129  * Decode an ASN1 item, this currently behaves just like a standard 'd2i'
130  * function. 'in' points to a buffer to read the data from, in future we
131  * will have more advanced versions that can input data a piece at a time and
132  * this will simply be a special case.
133  */
134 
ASN1_item_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_ITEM * it)135 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
136                           const unsigned char **in, long len,
137                           const ASN1_ITEM *it)
138 {
139     ASN1_TLC c;
140     ASN1_VALUE *ptmpval = NULL;
141     if (!pval)
142         pval = &ptmpval;
143     c.valid = 0;
144     if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
145         return *pval;
146     return NULL;
147 }
148 
ASN1_template_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_TEMPLATE * tt)149 int ASN1_template_d2i(ASN1_VALUE **pval,
150                       const unsigned char **in, long len,
151                       const ASN1_TEMPLATE *tt)
152 {
153     ASN1_TLC c;
154     c.valid = 0;
155     return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
156 }
157 
158 /*
159  * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and
160  * tag mismatch return -1 to handle OPTIONAL
161  */
162 
ASN1_item_ex_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_ITEM * it,int tag,int aclass,char opt,ASN1_TLC * ctx)163 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
164                      const ASN1_ITEM *it,
165                      int tag, int aclass, char opt, ASN1_TLC *ctx)
166 {
167     const ASN1_TEMPLATE *tt, *errtt = NULL;
168     const ASN1_COMPAT_FUNCS *cf;
169     const ASN1_EXTERN_FUNCS *ef;
170     const ASN1_AUX *aux = it->funcs;
171     ASN1_aux_cb *asn1_cb;
172     const unsigned char *p = NULL, *q;
173     unsigned char *wp = NULL;   /* BIG FAT WARNING! BREAKS CONST WHERE USED */
174     unsigned char imphack = 0, oclass;
175     char seq_eoc, seq_nolen, cst, isopt;
176     long tmplen;
177     int i;
178     int otag;
179     int ret = 0;
180     ASN1_VALUE **pchptr, *ptmpval;
181     int combine = aclass & ASN1_TFLG_COMBINE;
182     aclass &= ~ASN1_TFLG_COMBINE;
183     if (!pval)
184         return 0;
185     if (aux && aux->asn1_cb)
186         asn1_cb = aux->asn1_cb;
187     else
188         asn1_cb = 0;
189 
190     switch (it->itype) {
191     case ASN1_ITYPE_PRIMITIVE:
192         if (it->templates) {
193             /*
194              * tagging or OPTIONAL is currently illegal on an item template
195              * because the flags can't get passed down. In practice this
196              * isn't a problem: we include the relevant flags from the item
197              * template in the template itself.
198              */
199             if ((tag != -1) || opt) {
200                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
201                         ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
202                 goto err;
203             }
204             return asn1_template_ex_d2i(pval, in, len,
205                                         it->templates, opt, ctx);
206         }
207         return asn1_d2i_ex_primitive(pval, in, len, it,
208                                      tag, aclass, opt, ctx);
209         break;
210 
211     case ASN1_ITYPE_MSTRING:
212         p = *in;
213         /* Just read in tag and class */
214         ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
215                               &p, len, -1, 0, 1, ctx);
216         if (!ret) {
217             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
218             goto err;
219         }
220 
221         /* Must be UNIVERSAL class */
222         if (oclass != V_ASN1_UNIVERSAL) {
223             /* If OPTIONAL, assume this is OK */
224             if (opt)
225                 return -1;
226             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL);
227             goto err;
228         }
229         /* Check tag matches bit map */
230         if (!(ASN1_tag2bit(otag) & it->utype)) {
231             /* If OPTIONAL, assume this is OK */
232             if (opt)
233                 return -1;
234             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG);
235             goto err;
236         }
237         return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx);
238 
239     case ASN1_ITYPE_EXTERN:
240         /* Use new style d2i */
241         ef = it->funcs;
242         return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx);
243 
244     case ASN1_ITYPE_COMPAT:
245         /* we must resort to old style evil hackery */
246         cf = it->funcs;
247 
248         /* If OPTIONAL see if it is there */
249         if (opt) {
250             int exptag;
251             p = *in;
252             if (tag == -1)
253                 exptag = it->utype;
254             else
255                 exptag = tag;
256             /*
257              * Don't care about anything other than presence of expected tag
258              */
259 
260             ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
261                                   &p, len, exptag, aclass, 1, ctx);
262             if (!ret) {
263                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
264                 goto err;
265             }
266             if (ret == -1)
267                 return -1;
268         }
269 
270         /*
271          * This is the old style evil hack IMPLICIT handling: since the
272          * underlying code is expecting a tag and class other than the one
273          * present we change the buffer temporarily then change it back
274          * afterwards. This doesn't and never did work for tags > 30. Yes
275          * this is *horrible* but it is only needed for old style d2i which
276          * will hopefully not be around for much longer. FIXME: should copy
277          * the buffer then modify it so the input buffer can be const: we
278          * should *always* copy because the old style d2i might modify the
279          * buffer.
280          */
281 
282         if (tag != -1) {
283             wp = *(unsigned char **)in;
284             imphack = *wp;
285             if (p == NULL) {
286                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
287                 goto err;
288             }
289             *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
290                                   | it->utype);
291         }
292 
293         ptmpval = cf->asn1_d2i(pval, in, len);
294 
295         if (tag != -1)
296             *wp = imphack;
297 
298         if (ptmpval)
299             return 1;
300 
301         ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
302         goto err;
303 
304     case ASN1_ITYPE_CHOICE:
305         if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
306             goto auxerr;
307         if (*pval) {
308             /* Free up and zero CHOICE value if initialised */
309             i = asn1_get_choice_selector(pval, it);
310             if ((i >= 0) && (i < it->tcount)) {
311                 tt = it->templates + i;
312                 pchptr = asn1_get_field_ptr(pval, tt);
313                 ASN1_template_free(pchptr, tt);
314                 asn1_set_choice_selector(pval, -1, it);
315             }
316         } else if (!ASN1_item_ex_new(pval, it)) {
317             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
318             goto err;
319         }
320         /* CHOICE type, try each possibility in turn */
321         p = *in;
322         for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
323             pchptr = asn1_get_field_ptr(pval, tt);
324             /*
325              * We mark field as OPTIONAL so its absence can be recognised.
326              */
327             ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
328             /* If field not present, try the next one */
329             if (ret == -1)
330                 continue;
331             /* If positive return, read OK, break loop */
332             if (ret > 0)
333                 break;
334             /* Otherwise must be an ASN1 parsing error */
335             errtt = tt;
336             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
337             goto err;
338         }
339 
340         /* Did we fall off the end without reading anything? */
341         if (i == it->tcount) {
342             /* If OPTIONAL, this is OK */
343             if (opt) {
344                 /* Free and zero it */
345                 ASN1_item_ex_free(pval, it);
346                 return -1;
347             }
348             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE);
349             goto err;
350         }
351 
352         asn1_set_choice_selector(pval, i, it);
353         *in = p;
354         if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
355             goto auxerr;
356         return 1;
357 
358     case ASN1_ITYPE_NDEF_SEQUENCE:
359     case ASN1_ITYPE_SEQUENCE:
360         p = *in;
361         tmplen = len;
362 
363         /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
364         if (tag == -1) {
365             tag = V_ASN1_SEQUENCE;
366             aclass = V_ASN1_UNIVERSAL;
367         }
368         /* Get SEQUENCE length and update len, p */
369         ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
370                               &p, len, tag, aclass, opt, ctx);
371         if (!ret) {
372             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
373             goto err;
374         } else if (ret == -1)
375             return -1;
376         if (aux && (aux->flags & ASN1_AFLG_BROKEN)) {
377             len = tmplen - (p - *in);
378             seq_nolen = 1;
379         }
380         /* If indefinite we don't do a length check */
381         else
382             seq_nolen = seq_eoc;
383         if (!cst) {
384             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
385             goto err;
386         }
387 
388         if (!*pval && !ASN1_item_ex_new(pval, it)) {
389             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
390             goto err;
391         }
392 
393         if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
394             goto auxerr;
395 
396         /* Free up and zero any ADB found */
397         for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
398             if (tt->flags & ASN1_TFLG_ADB_MASK) {
399                 const ASN1_TEMPLATE *seqtt;
400                 ASN1_VALUE **pseqval;
401                 seqtt = asn1_do_adb(pval, tt, 1);
402                 pseqval = asn1_get_field_ptr(pval, seqtt);
403                 ASN1_template_free(pseqval, seqtt);
404             }
405         }
406 
407         /* Get each field entry */
408         for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
409             const ASN1_TEMPLATE *seqtt;
410             ASN1_VALUE **pseqval;
411             seqtt = asn1_do_adb(pval, tt, 1);
412             if (!seqtt)
413                 goto err;
414             pseqval = asn1_get_field_ptr(pval, seqtt);
415             /* Have we ran out of data? */
416             if (!len)
417                 break;
418             q = p;
419             if (asn1_check_eoc(&p, len)) {
420                 if (!seq_eoc) {
421                     ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC);
422                     goto err;
423                 }
424                 len -= p - q;
425                 seq_eoc = 0;
426                 q = p;
427                 break;
428             }
429             /*
430              * This determines the OPTIONAL flag value. The field cannot be
431              * omitted if it is the last of a SEQUENCE and there is still
432              * data to be read. This isn't strictly necessary but it
433              * increases efficiency in some cases.
434              */
435             if (i == (it->tcount - 1))
436                 isopt = 0;
437             else
438                 isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
439             /*
440              * attempt to read in field, allowing each to be OPTIONAL
441              */
442 
443             ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx);
444             if (!ret) {
445                 errtt = seqtt;
446                 goto err;
447             } else if (ret == -1) {
448                 /*
449                  * OPTIONAL component absent. Free and zero the field.
450                  */
451                 ASN1_template_free(pseqval, seqtt);
452                 continue;
453             }
454             /* Update length */
455             len -= p - q;
456         }
457 
458         /* Check for EOC if expecting one */
459         if (seq_eoc && !asn1_check_eoc(&p, len)) {
460             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
461             goto err;
462         }
463         /* Check all data read */
464         if (!seq_nolen && len) {
465             ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH);
466             goto err;
467         }
468 
469         /*
470          * If we get here we've got no more data in the SEQUENCE, however we
471          * may not have read all fields so check all remaining are OPTIONAL
472          * and clear any that are.
473          */
474         for (; i < it->tcount; tt++, i++) {
475             const ASN1_TEMPLATE *seqtt;
476             seqtt = asn1_do_adb(pval, tt, 1);
477             if (!seqtt)
478                 goto err;
479             if (seqtt->flags & ASN1_TFLG_OPTIONAL) {
480                 ASN1_VALUE **pseqval;
481                 pseqval = asn1_get_field_ptr(pval, seqtt);
482                 ASN1_template_free(pseqval, seqtt);
483             } else {
484                 errtt = seqtt;
485                 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING);
486                 goto err;
487             }
488         }
489         /* Save encoding */
490         if (!asn1_enc_save(pval, *in, p - *in, it))
491             goto auxerr;
492         *in = p;
493         if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
494             goto auxerr;
495         return 1;
496 
497     default:
498         return 0;
499     }
500  auxerr:
501     ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
502  err:
503     if (combine == 0)
504         ASN1_item_ex_free(pval, it);
505     if (errtt)
506         ERR_add_error_data(4, "Field=", errtt->field_name,
507                            ", Type=", it->sname);
508     else
509         ERR_add_error_data(2, "Type=", it->sname);
510     return 0;
511 }
512 
513 /*
514  * Templates are handled with two separate functions. One handles any
515  * EXPLICIT tag and the other handles the rest.
516  */
517 
asn1_template_ex_d2i(ASN1_VALUE ** val,const unsigned char ** in,long inlen,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)518 static int asn1_template_ex_d2i(ASN1_VALUE **val,
519                                 const unsigned char **in, long inlen,
520                                 const ASN1_TEMPLATE *tt, char opt,
521                                 ASN1_TLC *ctx)
522 {
523     int flags, aclass;
524     int ret;
525     long len;
526     const unsigned char *p, *q;
527     char exp_eoc;
528     if (!val)
529         return 0;
530     flags = tt->flags;
531     aclass = flags & ASN1_TFLG_TAG_CLASS;
532 
533     p = *in;
534 
535     /* Check if EXPLICIT tag expected */
536     if (flags & ASN1_TFLG_EXPTAG) {
537         char cst;
538         /*
539          * Need to work out amount of data available to the inner content and
540          * where it starts: so read in EXPLICIT header to get the info.
541          */
542         ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
543                               &p, inlen, tt->tag, aclass, opt, ctx);
544         q = p;
545         if (!ret) {
546             ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
547             return 0;
548         } else if (ret == -1)
549             return -1;
550         if (!cst) {
551             ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
552                     ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
553             return 0;
554         }
555         /* We've found the field so it can't be OPTIONAL now */
556         ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
557         if (!ret) {
558             ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
559             return 0;
560         }
561         /* We read the field in OK so update length */
562         len -= p - q;
563         if (exp_eoc) {
564             /* If NDEF we must have an EOC here */
565             if (!asn1_check_eoc(&p, len)) {
566                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_MISSING_EOC);
567                 goto err;
568             }
569         } else {
570             /*
571              * Otherwise we must hit the EXPLICIT tag end or its an error
572              */
573             if (len) {
574                 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
575                         ASN1_R_EXPLICIT_LENGTH_MISMATCH);
576                 goto err;
577             }
578         }
579     } else
580         return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx);
581 
582     *in = p;
583     return 1;
584 
585  err:
586     ASN1_template_free(val, tt);
587     return 0;
588 }
589 
asn1_template_noexp_d2i(ASN1_VALUE ** val,const unsigned char ** in,long len,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)590 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
591                                    const unsigned char **in, long len,
592                                    const ASN1_TEMPLATE *tt, char opt,
593                                    ASN1_TLC *ctx)
594 {
595     int flags, aclass;
596     int ret;
597     const unsigned char *p, *q;
598     if (!val)
599         return 0;
600     flags = tt->flags;
601     aclass = flags & ASN1_TFLG_TAG_CLASS;
602 
603     p = *in;
604     q = p;
605 
606     if (flags & ASN1_TFLG_SK_MASK) {
607         /* SET OF, SEQUENCE OF */
608         int sktag, skaclass;
609         char sk_eoc;
610         /* First work out expected inner tag value */
611         if (flags & ASN1_TFLG_IMPTAG) {
612             sktag = tt->tag;
613             skaclass = aclass;
614         } else {
615             skaclass = V_ASN1_UNIVERSAL;
616             if (flags & ASN1_TFLG_SET_OF)
617                 sktag = V_ASN1_SET;
618             else
619                 sktag = V_ASN1_SEQUENCE;
620         }
621         /* Get the tag */
622         ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
623                               &p, len, sktag, skaclass, opt, ctx);
624         if (!ret) {
625             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
626             return 0;
627         } else if (ret == -1)
628             return -1;
629         if (!*val)
630             *val = (ASN1_VALUE *)sk_new_null();
631         else {
632             /*
633              * We've got a valid STACK: free up any items present
634              */
635             STACK *sktmp = (STACK *) * val;
636             ASN1_VALUE *vtmp;
637             while (sk_num(sktmp) > 0) {
638                 vtmp = (ASN1_VALUE *)sk_pop(sktmp);
639                 ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item));
640             }
641         }
642 
643         if (!*val) {
644             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE);
645             goto err;
646         }
647 
648         /* Read as many items as we can */
649         while (len > 0) {
650             ASN1_VALUE *skfield;
651             q = p;
652             /* See if EOC found */
653             if (asn1_check_eoc(&p, len)) {
654                 if (!sk_eoc) {
655                     ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
656                             ASN1_R_UNEXPECTED_EOC);
657                     goto err;
658                 }
659                 len -= p - q;
660                 sk_eoc = 0;
661                 break;
662             }
663             skfield = NULL;
664             if (!ASN1_item_ex_d2i(&skfield, &p, len,
665                                   ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) {
666                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
667                         ERR_R_NESTED_ASN1_ERROR);
668                 goto err;
669             }
670             len -= p - q;
671             if (!sk_push((STACK *) * val, (char *)skfield)) {
672                 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE);
673                 goto err;
674             }
675         }
676         if (sk_eoc) {
677             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
678             goto err;
679         }
680     } else if (flags & ASN1_TFLG_IMPTAG) {
681         /* IMPLICIT tagging */
682         ret = ASN1_item_ex_d2i(val, &p, len,
683                                ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt,
684                                ctx);
685         if (!ret) {
686             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
687             goto err;
688         } else if (ret == -1)
689             return -1;
690     } else {
691         /* Nothing special */
692         ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
693                                -1, tt->flags & ASN1_TFLG_COMBINE, opt, ctx);
694         if (!ret) {
695             ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
696             goto err;
697         } else if (ret == -1)
698             return -1;
699     }
700 
701     *in = p;
702     return 1;
703 
704  err:
705     ASN1_template_free(val, tt);
706     return 0;
707 }
708 
asn1_d2i_ex_primitive(ASN1_VALUE ** pval,const unsigned char ** in,long inlen,const ASN1_ITEM * it,int tag,int aclass,char opt,ASN1_TLC * ctx)709 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
710                                  const unsigned char **in, long inlen,
711                                  const ASN1_ITEM *it,
712                                  int tag, int aclass, char opt, ASN1_TLC *ctx)
713 {
714     int ret = 0, utype;
715     long plen;
716     char cst, inf, free_cont = 0;
717     const unsigned char *p;
718     BUF_MEM buf;
719     const unsigned char *cont = NULL;
720     long len;
721     if (!pval) {
722         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
723         return 0;               /* Should never happen */
724     }
725 
726     if (it->itype == ASN1_ITYPE_MSTRING) {
727         utype = tag;
728         tag = -1;
729     } else
730         utype = it->utype;
731 
732     if (utype == V_ASN1_ANY) {
733         /* If type is ANY need to figure out type from tag */
734         unsigned char oclass;
735         if (tag >= 0) {
736             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY);
737             return 0;
738         }
739         if (opt) {
740             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
741                     ASN1_R_ILLEGAL_OPTIONAL_ANY);
742             return 0;
743         }
744         p = *in;
745         ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
746                               &p, inlen, -1, 0, 0, ctx);
747         if (!ret) {
748             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
749             return 0;
750         }
751         if (oclass != V_ASN1_UNIVERSAL)
752             utype = V_ASN1_OTHER;
753     }
754     if (tag == -1) {
755         tag = utype;
756         aclass = V_ASN1_UNIVERSAL;
757     }
758     p = *in;
759     /* Check header */
760     ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
761                           &p, inlen, tag, aclass, opt, ctx);
762     if (!ret) {
763         ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
764         return 0;
765     } else if (ret == -1)
766         return -1;
767     ret = 0;
768     /* SEQUENCE, SET and "OTHER" are left in encoded form */
769     if ((utype == V_ASN1_SEQUENCE)
770         || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) {
771         /*
772          * Clear context cache for type OTHER because the auto clear when we
773          * have a exact match wont work
774          */
775         if (utype == V_ASN1_OTHER) {
776             asn1_tlc_clear(ctx);
777         }
778         /* SEQUENCE and SET must be constructed */
779         else if (!cst) {
780             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
781                     ASN1_R_TYPE_NOT_CONSTRUCTED);
782             return 0;
783         }
784 
785         cont = *in;
786         /* If indefinite length constructed find the real end */
787         if (inf) {
788             if (!asn1_find_end(&p, plen, inf))
789                 goto err;
790             len = p - cont;
791         } else {
792             len = p - cont + plen;
793             p += plen;
794             buf.data = NULL;
795         }
796     } else if (cst) {
797         if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
798             || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
799             || utype == V_ASN1_ENUMERATED) {
800             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE);
801             return 0;
802         }
803         buf.length = 0;
804         buf.max = 0;
805         buf.data = NULL;
806         /*
807          * Should really check the internal tags are correct but some things
808          * may get this wrong. The relevant specs say that constructed string
809          * types should be OCTET STRINGs internally irrespective of the type.
810          * So instead just check for UNIVERSAL class and ignore the tag.
811          */
812         if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0)) {
813             free_cont = 1;
814             goto err;
815         }
816         len = buf.length;
817         /* Append a final null to string */
818         if (!BUF_MEM_grow_clean(&buf, len + 1)) {
819             ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
820             return 0;
821         }
822         buf.data[len] = 0;
823         cont = (const unsigned char *)buf.data;
824         free_cont = 1;
825     } else {
826         cont = p;
827         len = plen;
828         p += plen;
829     }
830 
831     /* We now have content length and type: translate into a structure */
832     if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
833         goto err;
834 
835     *in = p;
836     ret = 1;
837  err:
838     if (free_cont && buf.data)
839         OPENSSL_free(buf.data);
840     return ret;
841 }
842 
843 /* Translate ASN1 content octets into a structure */
844 
asn1_ex_c2i(ASN1_VALUE ** pval,const unsigned char * cont,int len,int utype,char * free_cont,const ASN1_ITEM * it)845 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
846                 int utype, char *free_cont, const ASN1_ITEM *it)
847 {
848     ASN1_VALUE **opval = NULL;
849     ASN1_STRING *stmp;
850     ASN1_TYPE *typ = NULL;
851     int ret = 0;
852     const ASN1_PRIMITIVE_FUNCS *pf;
853     ASN1_INTEGER **tint;
854     pf = it->funcs;
855 
856     if (pf && pf->prim_c2i)
857         return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
858     /* If ANY type clear type and set pointer to internal value */
859     if (it->utype == V_ASN1_ANY) {
860         if (!*pval) {
861             typ = ASN1_TYPE_new();
862             if (typ == NULL)
863                 goto err;
864             *pval = (ASN1_VALUE *)typ;
865         } else
866             typ = (ASN1_TYPE *)*pval;
867 
868         if (utype != typ->type)
869             ASN1_TYPE_set(typ, utype, NULL);
870         opval = pval;
871         pval = &typ->value.asn1_value;
872     }
873     switch (utype) {
874     case V_ASN1_OBJECT:
875         if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
876             goto err;
877         break;
878 
879     case V_ASN1_NULL:
880         if (len) {
881             ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_NULL_IS_WRONG_LENGTH);
882             goto err;
883         }
884         *pval = (ASN1_VALUE *)1;
885         break;
886 
887     case V_ASN1_BOOLEAN:
888         if (len != 1) {
889             ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
890             goto err;
891         } else {
892             ASN1_BOOLEAN *tbool;
893             tbool = (ASN1_BOOLEAN *)pval;
894             *tbool = *cont;
895         }
896         break;
897 
898     case V_ASN1_BIT_STRING:
899         if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
900             goto err;
901         break;
902 
903     case V_ASN1_INTEGER:
904     case V_ASN1_ENUMERATED:
905         tint = (ASN1_INTEGER **)pval;
906         if (!c2i_ASN1_INTEGER(tint, &cont, len))
907             goto err;
908         /* Fixup type to match the expected form */
909         (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
910         break;
911 
912     case V_ASN1_OCTET_STRING:
913     case V_ASN1_NUMERICSTRING:
914     case V_ASN1_PRINTABLESTRING:
915     case V_ASN1_T61STRING:
916     case V_ASN1_VIDEOTEXSTRING:
917     case V_ASN1_IA5STRING:
918     case V_ASN1_UTCTIME:
919     case V_ASN1_GENERALIZEDTIME:
920     case V_ASN1_GRAPHICSTRING:
921     case V_ASN1_VISIBLESTRING:
922     case V_ASN1_GENERALSTRING:
923     case V_ASN1_UNIVERSALSTRING:
924     case V_ASN1_BMPSTRING:
925     case V_ASN1_UTF8STRING:
926     case V_ASN1_OTHER:
927     case V_ASN1_SET:
928     case V_ASN1_SEQUENCE:
929     default:
930         if (utype == V_ASN1_BMPSTRING && (len & 1)) {
931             ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
932             goto err;
933         }
934         if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) {
935             ASN1err(ASN1_F_ASN1_EX_C2I,
936                     ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
937             goto err;
938         }
939         /* All based on ASN1_STRING and handled the same */
940         if (!*pval) {
941             stmp = ASN1_STRING_type_new(utype);
942             if (!stmp) {
943                 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE);
944                 goto err;
945             }
946             *pval = (ASN1_VALUE *)stmp;
947         } else {
948             stmp = (ASN1_STRING *)*pval;
949             stmp->type = utype;
950         }
951         /* If we've already allocated a buffer use it */
952         if (*free_cont) {
953             if (stmp->data)
954                 OPENSSL_free(stmp->data);
955             stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
956             stmp->length = len;
957             *free_cont = 0;
958         } else {
959             if (!ASN1_STRING_set(stmp, cont, len)) {
960                 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE);
961                 ASN1_STRING_free(stmp);
962                 *pval = NULL;
963                 goto err;
964             }
965         }
966         break;
967     }
968     /* If ASN1_ANY and NULL type fix up value */
969     if (typ && (utype == V_ASN1_NULL))
970         typ->value.ptr = NULL;
971 
972     ret = 1;
973  err:
974     if (!ret) {
975         ASN1_TYPE_free(typ);
976         if (opval)
977             *opval = NULL;
978     }
979     return ret;
980 }
981 
982 /*
983  * This function finds the end of an ASN1 structure when passed its maximum
984  * length, whether it is indefinite length and a pointer to the content. This
985  * is more efficient than calling asn1_collect because it does not recurse on
986  * each indefinite length header.
987  */
988 
asn1_find_end(const unsigned char ** in,long len,char inf)989 static int asn1_find_end(const unsigned char **in, long len, char inf)
990 {
991     int expected_eoc;
992     long plen;
993     const unsigned char *p = *in, *q;
994     /* If not indefinite length constructed just add length */
995     if (inf == 0) {
996         *in += len;
997         return 1;
998     }
999     expected_eoc = 1;
1000     /*
1001      * Indefinite length constructed form. Find the end when enough EOCs are
1002      * found. If more indefinite length constructed headers are encountered
1003      * increment the expected eoc count otherwise just skip to the end of the
1004      * data.
1005      */
1006     while (len > 0) {
1007         if (asn1_check_eoc(&p, len)) {
1008             expected_eoc--;
1009             if (expected_eoc == 0)
1010                 break;
1011             len -= 2;
1012             continue;
1013         }
1014         q = p;
1015         /* Just read in a header: only care about the length */
1016         if (!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1017                              -1, 0, 0, NULL)) {
1018             ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1019             return 0;
1020         }
1021         if (inf)
1022             expected_eoc++;
1023         else
1024             p += plen;
1025         len -= p - q;
1026     }
1027     if (expected_eoc) {
1028         ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1029         return 0;
1030     }
1031     *in = p;
1032     return 1;
1033 }
1034 
1035 /*
1036  * This function collects the asn1 data from a constructred string type into
1037  * a buffer. The values of 'in' and 'len' should refer to the contents of the
1038  * constructed type and 'inf' should be set if it is indefinite length.
1039  */
1040 
1041 #ifndef ASN1_MAX_STRING_NEST
1042 /*
1043  * This determines how many levels of recursion are permitted in ASN1 string
1044  * types. If it is not limited stack overflows can occur. If set to zero no
1045  * recursion is allowed at all. Although zero should be adequate examples
1046  * exist that require a value of 1. So 5 should be more than enough.
1047  */
1048 # define ASN1_MAX_STRING_NEST 5
1049 #endif
1050 
asn1_collect(BUF_MEM * buf,const unsigned char ** in,long len,char inf,int tag,int aclass,int depth)1051 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1052                         char inf, int tag, int aclass, int depth)
1053 {
1054     const unsigned char *p, *q;
1055     long plen;
1056     char cst, ininf;
1057     p = *in;
1058     inf &= 1;
1059     /*
1060      * If no buffer and not indefinite length constructed just pass over the
1061      * encoded data
1062      */
1063     if (!buf && !inf) {
1064         *in += len;
1065         return 1;
1066     }
1067     while (len > 0) {
1068         q = p;
1069         /* Check for EOC */
1070         if (asn1_check_eoc(&p, len)) {
1071             /*
1072              * EOC is illegal outside indefinite length constructed form
1073              */
1074             if (!inf) {
1075                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC);
1076                 return 0;
1077             }
1078             inf = 0;
1079             break;
1080         }
1081 
1082         if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1083                              len, tag, aclass, 0, NULL)) {
1084             ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1085             return 0;
1086         }
1087 
1088         /* If indefinite length constructed update max length */
1089         if (cst) {
1090             if (depth >= ASN1_MAX_STRING_NEST) {
1091                 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
1092                 return 0;
1093             }
1094             if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1))
1095                 return 0;
1096         } else if (plen && !collect_data(buf, &p, plen))
1097             return 0;
1098         len -= p - q;
1099     }
1100     if (inf) {
1101         ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1102         return 0;
1103     }
1104     *in = p;
1105     return 1;
1106 }
1107 
collect_data(BUF_MEM * buf,const unsigned char ** p,long plen)1108 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1109 {
1110     int len;
1111     if (buf) {
1112         len = buf->length;
1113         if (!BUF_MEM_grow_clean(buf, len + plen)) {
1114             ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1115             return 0;
1116         }
1117         memcpy(buf->data + len, *p, plen);
1118     }
1119     *p += plen;
1120     return 1;
1121 }
1122 
1123 /* Check for ASN1 EOC and swallow it if found */
1124 
asn1_check_eoc(const unsigned char ** in,long len)1125 static int asn1_check_eoc(const unsigned char **in, long len)
1126 {
1127     const unsigned char *p;
1128     if (len < 2)
1129         return 0;
1130     p = *in;
1131     if (!p[0] && !p[1]) {
1132         *in += 2;
1133         return 1;
1134     }
1135     return 0;
1136 }
1137 
1138 /*
1139  * Check an ASN1 tag and length: a bit like ASN1_get_object but it sets the
1140  * length for indefinite length constructed form, we don't know the exact
1141  * length but we can set an upper bound to the amount of data available minus
1142  * the header length just read.
1143  */
1144 
asn1_check_tlen(long * olen,int * otag,unsigned char * oclass,char * inf,char * cst,const unsigned char ** in,long len,int exptag,int expclass,char opt,ASN1_TLC * ctx)1145 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1146                            char *inf, char *cst,
1147                            const unsigned char **in, long len,
1148                            int exptag, int expclass, char opt, ASN1_TLC *ctx)
1149 {
1150     int i;
1151     int ptag, pclass;
1152     long plen;
1153     const unsigned char *p, *q;
1154     p = *in;
1155     q = p;
1156 
1157     if (ctx && ctx->valid) {
1158         i = ctx->ret;
1159         plen = ctx->plen;
1160         pclass = ctx->pclass;
1161         ptag = ctx->ptag;
1162         p += ctx->hdrlen;
1163     } else {
1164         i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1165         if (ctx) {
1166             ctx->ret = i;
1167             ctx->plen = plen;
1168             ctx->pclass = pclass;
1169             ctx->ptag = ptag;
1170             ctx->hdrlen = p - q;
1171             ctx->valid = 1;
1172             /*
1173              * If definite length, and no error, length + header can't exceed
1174              * total amount of data available.
1175              */
1176             if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) {
1177                 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG);
1178                 asn1_tlc_clear(ctx);
1179                 return 0;
1180             }
1181         }
1182     }
1183 
1184     if (i & 0x80) {
1185         ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1186         asn1_tlc_clear(ctx);
1187         return 0;
1188     }
1189     if (exptag >= 0) {
1190         if ((exptag != ptag) || (expclass != pclass)) {
1191             /*
1192              * If type is OPTIONAL, not an error: indicate missing type.
1193              */
1194             if (opt)
1195                 return -1;
1196             asn1_tlc_clear(ctx);
1197             ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1198             return 0;
1199         }
1200         /*
1201          * We have a tag and class match: assume we are going to do something
1202          * with it
1203          */
1204         asn1_tlc_clear(ctx);
1205     }
1206 
1207     if (i & 1)
1208         plen = len - (p - q);
1209 
1210     if (inf)
1211         *inf = i & 1;
1212 
1213     if (cst)
1214         *cst = i & V_ASN1_CONSTRUCTED;
1215 
1216     if (olen)
1217         *olen = plen;
1218 
1219     if (oclass)
1220         *oclass = pclass;
1221 
1222     if (otag)
1223         *otag = ptag;
1224 
1225     *in = p;
1226     return 1;
1227 }
1228