xref: /freebsd/crypto/openssl/crypto/asn1/tasn_dec.c (revision 830940567b49bb0c08dfaed40418999e76616909)
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 
118 /* Decode an ASN1 item, this currently behaves just
119  * like a standard 'd2i' function. 'in' points to
120  * a buffer to read the data from, in future we will
121  * have more advanced versions that can input data
122  * a piece at a time and this will simply be a special
123  * case.
124  */
125 
126 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
127 		const unsigned char **in, long len, const ASN1_ITEM *it)
128 	{
129 	ASN1_TLC c;
130 	ASN1_VALUE *ptmpval = NULL;
131 	if (!pval)
132 		pval = &ptmpval;
133 	c.valid = 0;
134 	if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
135 		return *pval;
136 	return NULL;
137 	}
138 
139 int ASN1_template_d2i(ASN1_VALUE **pval,
140 		const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
141 	{
142 	ASN1_TLC c;
143 	c.valid = 0;
144 	return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
145 	}
146 
147 
148 /* Decode an item, taking care of IMPLICIT tagging, if any.
149  * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
150  */
151 
152 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
153 			const ASN1_ITEM *it,
154 			int tag, int aclass, char opt, ASN1_TLC *ctx)
155 	{
156 	const ASN1_TEMPLATE *tt, *errtt = NULL;
157 	const ASN1_COMPAT_FUNCS *cf;
158 	const ASN1_EXTERN_FUNCS *ef;
159 	const ASN1_AUX *aux = it->funcs;
160 	ASN1_aux_cb *asn1_cb;
161 	const unsigned char *p = NULL, *q;
162 	unsigned char *wp=NULL;	/* BIG FAT WARNING!  BREAKS CONST WHERE USED */
163 	unsigned char imphack = 0, oclass;
164 	char seq_eoc, seq_nolen, cst, isopt;
165 	long tmplen;
166 	int i;
167 	int otag;
168 	int ret = 0;
169 	ASN1_VALUE *pchval, **pchptr, *ptmpval;
170 	if (!pval)
171 		return 0;
172 	if (aux && aux->asn1_cb)
173 		asn1_cb = aux->asn1_cb;
174 	else asn1_cb = 0;
175 
176 	switch(it->itype)
177 		{
178 		case ASN1_ITYPE_PRIMITIVE:
179 		if (it->templates)
180 			{
181 			/* tagging or OPTIONAL is currently illegal on an item
182 			 * template because the flags can't get passed down.
183 			 * In practice this isn't a problem: we include the
184 			 * relevant flags from the item template in the
185 			 * template itself.
186 			 */
187 			if ((tag != -1) || opt)
188 				{
189 				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
190 				ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
191 				goto err;
192 				}
193 			return asn1_template_ex_d2i(pval, in, len,
194 					it->templates, opt, ctx);
195 		}
196 		return asn1_d2i_ex_primitive(pval, in, len, it,
197 						tag, aclass, opt, ctx);
198 		break;
199 
200 		case ASN1_ITYPE_MSTRING:
201 		p = *in;
202 		/* Just read in tag and class */
203 		ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
204 						&p, len, -1, 0, 1, ctx);
205 		if (!ret)
206 			{
207 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
208 					ERR_R_NESTED_ASN1_ERROR);
209 			goto err;
210 			}
211 
212 		/* Must be UNIVERSAL class */
213 		if (oclass != V_ASN1_UNIVERSAL)
214 			{
215 			/* If OPTIONAL, assume this is OK */
216 			if (opt) return -1;
217 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
218 					ASN1_R_MSTRING_NOT_UNIVERSAL);
219 			goto err;
220 			}
221 		/* Check tag matches bit map */
222 		if (!(ASN1_tag2bit(otag) & it->utype))
223 			{
224 			/* If OPTIONAL, assume this is OK */
225 			if (opt)
226 				return -1;
227 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
228 					ASN1_R_MSTRING_WRONG_TAG);
229 			goto err;
230 			}
231 		return asn1_d2i_ex_primitive(pval, in, len,
232 						it, otag, 0, 0, ctx);
233 
234 		case ASN1_ITYPE_EXTERN:
235 		/* Use new style d2i */
236 		ef = it->funcs;
237 		return ef->asn1_ex_d2i(pval, in, len,
238 						it, tag, aclass, opt, ctx);
239 
240 		case ASN1_ITYPE_COMPAT:
241 		/* we must resort to old style evil hackery */
242 		cf = it->funcs;
243 
244 		/* If OPTIONAL see if it is there */
245 		if (opt)
246 			{
247 			int exptag;
248 			p = *in;
249 			if (tag == -1)
250 				exptag = it->utype;
251 			else exptag = tag;
252 			/* Don't care about anything other than presence
253 			 * of expected tag */
254 
255 			ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
256 					&p, len, exptag, aclass, 1, ctx);
257 			if (!ret)
258 				{
259 				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
260 					ERR_R_NESTED_ASN1_ERROR);
261 				goto err;
262 				}
263 			if (ret == -1)
264 				return -1;
265 			}
266 
267 		/* This is the old style evil hack IMPLICIT handling:
268 		 * since the underlying code is expecting a tag and
269 		 * class other than the one present we change the
270 		 * buffer temporarily then change it back afterwards.
271 		 * This doesn't and never did work for tags > 30.
272 		 *
273 		 * Yes this is *horrible* but it is only needed for
274 		 * old style d2i which will hopefully not be around
275 		 * for much longer.
276 		 * FIXME: should copy the buffer then modify it so
277 		 * the input buffer can be const: we should *always*
278 		 * copy because the old style d2i might modify the
279 		 * buffer.
280 		 */
281 
282 		if (tag != -1)
283 			{
284 			wp = *(unsigned char **)in;
285 			imphack = *wp;
286 			if (p == NULL)
287 				{
288 				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
289 					ERR_R_NESTED_ASN1_ERROR);
290 				goto err;
291 				}
292 			*wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
293 								| it->utype);
294 			}
295 
296 		ptmpval = cf->asn1_d2i(pval, in, len);
297 
298 		if (tag != -1)
299 			*wp = imphack;
300 
301 		if (ptmpval)
302 			return 1;
303 
304 		ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
305 		goto err;
306 
307 
308 		case ASN1_ITYPE_CHOICE:
309 		if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
310 				goto auxerr;
311 
312 		/* Allocate structure */
313 		if (!*pval && !ASN1_item_ex_new(pval, it))
314 			{
315 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
316 						ERR_R_NESTED_ASN1_ERROR);
317 			goto err;
318 			}
319 		/* CHOICE type, try each possibility in turn */
320 		pchval = NULL;
321 		p = *in;
322 		for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
323 			{
324 			pchptr = asn1_get_field_ptr(pval, tt);
325 			/* We mark field as OPTIONAL so its absence
326 			 * can be recognised.
327 			 */
328 			ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
329 			/* If field not present, try the next one */
330 			if (ret == -1)
331 				continue;
332 			/* If positive return, read OK, break loop */
333 			if (ret > 0)
334 				break;
335 			/* Otherwise must be an ASN1 parsing error */
336 			errtt = tt;
337 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
338 						ERR_R_NESTED_ASN1_ERROR);
339 			goto err;
340 			}
341 
342 		/* Did we fall off the end without reading anything? */
343 		if (i == it->tcount)
344 			{
345 			/* If OPTIONAL, this is OK */
346 			if (opt)
347 				{
348 				/* Free and zero it */
349 				ASN1_item_ex_free(pval, it);
350 				return -1;
351 				}
352 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
353 					ASN1_R_NO_MATCHING_CHOICE_TYPE);
354 			goto err;
355 			}
356 
357 		asn1_set_choice_selector(pval, i, it);
358 		*in = p;
359 		if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
360 				goto auxerr;
361 		return 1;
362 
363 		case ASN1_ITYPE_NDEF_SEQUENCE:
364 		case ASN1_ITYPE_SEQUENCE:
365 		p = *in;
366 		tmplen = len;
367 
368 		/* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
369 		if (tag == -1)
370 			{
371 			tag = V_ASN1_SEQUENCE;
372 			aclass = V_ASN1_UNIVERSAL;
373 			}
374 		/* Get SEQUENCE length and update len, p */
375 		ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
376 					&p, len, tag, aclass, opt, ctx);
377 		if (!ret)
378 			{
379 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
380 					ERR_R_NESTED_ASN1_ERROR);
381 			goto err;
382 			}
383 		else if (ret == -1)
384 			return -1;
385 		if (aux && (aux->flags & ASN1_AFLG_BROKEN))
386 			{
387 			len = tmplen - (p - *in);
388 			seq_nolen = 1;
389 			}
390 		/* If indefinite we don't do a length check */
391 		else seq_nolen = seq_eoc;
392 		if (!cst)
393 			{
394 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
395 				ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
396 			goto err;
397 			}
398 
399 		if (!*pval && !ASN1_item_ex_new(pval, it))
400 			{
401 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
402 				ERR_R_NESTED_ASN1_ERROR);
403 			goto err;
404 			}
405 
406 		if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it))
407 				goto auxerr;
408 
409 		/* Get each field entry */
410 		for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
411 			{
412 			const ASN1_TEMPLATE *seqtt;
413 			ASN1_VALUE **pseqval;
414 			seqtt = asn1_do_adb(pval, tt, 1);
415 			if (!seqtt)
416 				goto err;
417 			pseqval = asn1_get_field_ptr(pval, seqtt);
418 			/* Have we ran out of data? */
419 			if (!len)
420 				break;
421 			q = p;
422 			if (asn1_check_eoc(&p, len))
423 				{
424 				if (!seq_eoc)
425 					{
426 					ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
427 							ASN1_R_UNEXPECTED_EOC);
428 					goto err;
429 					}
430 				len -= p - q;
431 				seq_eoc = 0;
432 				q = p;
433 				break;
434 				}
435 			/* This determines the OPTIONAL flag value. The field
436 			 * cannot be omitted if it is the last of a SEQUENCE
437 			 * and there is still data to be read. This isn't
438 			 * strictly necessary but it increases efficiency in
439 			 * some cases.
440 			 */
441 			if (i == (it->tcount - 1))
442 				isopt = 0;
443 			else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
444 			/* attempt to read in field, allowing each to be
445 			 * OPTIONAL */
446 
447 			ret = asn1_template_ex_d2i(pseqval, &p, len,
448 							seqtt, isopt, ctx);
449 			if (!ret)
450 				{
451 				errtt = seqtt;
452 				goto err;
453 				}
454 			else if (ret == -1)
455 				{
456 				/* OPTIONAL component absent.
457 				 * Free and zero the field.
458 				 */
459 				ASN1_template_free(pseqval, seqtt);
460 				continue;
461 				}
462 			/* Update length */
463 			len -= p - q;
464 			}
465 
466 		/* Check for EOC if expecting one */
467 		if (seq_eoc && !asn1_check_eoc(&p, len))
468 			{
469 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
470 			goto err;
471 			}
472 		/* Check all data read */
473 		if (!seq_nolen && len)
474 			{
475 			ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
476 					ASN1_R_SEQUENCE_LENGTH_MISMATCH);
477 			goto err;
478 			}
479 
480 		/* If we get here we've got no more data in the SEQUENCE,
481 		 * however we may not have read all fields so check all
482 		 * remaining are OPTIONAL and clear any that are.
483 		 */
484 		for (; i < it->tcount; tt++, i++)
485 			{
486 			const ASN1_TEMPLATE *seqtt;
487 			seqtt = asn1_do_adb(pval, tt, 1);
488 			if (!seqtt)
489 				goto err;
490 			if (seqtt->flags & ASN1_TFLG_OPTIONAL)
491 				{
492 				ASN1_VALUE **pseqval;
493 				pseqval = asn1_get_field_ptr(pval, seqtt);
494 				ASN1_template_free(pseqval, seqtt);
495 				}
496 			else
497 				{
498 				errtt = seqtt;
499 				ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
500 							ASN1_R_FIELD_MISSING);
501 				goto err;
502 				}
503 			}
504 		/* Save encoding */
505 		if (!asn1_enc_save(pval, *in, p - *in, it))
506 			goto auxerr;
507 		*in = p;
508 		if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it))
509 				goto auxerr;
510 		return 1;
511 
512 		default:
513 		return 0;
514 		}
515 	auxerr:
516 	ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
517 	err:
518 	ASN1_item_ex_free(pval, it);
519 	if (errtt)
520 		ERR_add_error_data(4, "Field=", errtt->field_name,
521 					", Type=", it->sname);
522 	else
523 		ERR_add_error_data(2, "Type=", it->sname);
524 	return 0;
525 	}
526 
527 /* Templates are handled with two separate functions.
528  * One handles any EXPLICIT tag and the other handles the rest.
529  */
530 
531 static int asn1_template_ex_d2i(ASN1_VALUE **val,
532 				const unsigned char **in, long inlen,
533 				const ASN1_TEMPLATE *tt, char opt,
534 							ASN1_TLC *ctx)
535 	{
536 	int flags, aclass;
537 	int ret;
538 	long len;
539 	const unsigned char *p, *q;
540 	char exp_eoc;
541 	if (!val)
542 		return 0;
543 	flags = tt->flags;
544 	aclass = flags & ASN1_TFLG_TAG_CLASS;
545 
546 	p = *in;
547 
548 	/* Check if EXPLICIT tag expected */
549 	if (flags & ASN1_TFLG_EXPTAG)
550 		{
551 		char cst;
552 		/* Need to work out amount of data available to the inner
553 		 * content and where it starts: so read in EXPLICIT header to
554 		 * get the info.
555 		 */
556 		ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
557 					&p, inlen, tt->tag, aclass, opt, ctx);
558 		q = p;
559 		if (!ret)
560 			{
561 			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
562 					ERR_R_NESTED_ASN1_ERROR);
563 			return 0;
564 			}
565 		else if (ret == -1)
566 			return -1;
567 		if (!cst)
568 			{
569 			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
570 					ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
571 			return 0;
572 			}
573 		/* We've found the field so it can't be OPTIONAL now */
574 		ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
575 		if (!ret)
576 			{
577 			ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
578 					ERR_R_NESTED_ASN1_ERROR);
579 			return 0;
580 			}
581 		/* We read the field in OK so update length */
582 		len -= p - q;
583 		if (exp_eoc)
584 			{
585 			/* If NDEF we must have an EOC here */
586 			if (!asn1_check_eoc(&p, len))
587 				{
588 				ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
589 						ASN1_R_MISSING_EOC);
590 				goto err;
591 				}
592 			}
593 		else
594 			{
595 			/* Otherwise we must hit the EXPLICIT tag end or its
596 			 * an error */
597 			if (len)
598 				{
599 				ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
600 					ASN1_R_EXPLICIT_LENGTH_MISMATCH);
601 				goto err;
602 				}
603 			}
604 		}
605 		else
606 			return asn1_template_noexp_d2i(val, in, inlen,
607 								tt, opt, ctx);
608 
609 	*in = p;
610 	return 1;
611 
612 	err:
613 	ASN1_template_free(val, tt);
614 	return 0;
615 	}
616 
617 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
618 				const unsigned char **in, long len,
619 				const ASN1_TEMPLATE *tt, char opt,
620 				ASN1_TLC *ctx)
621 	{
622 	int flags, aclass;
623 	int ret;
624 	const unsigned char *p, *q;
625 	if (!val)
626 		return 0;
627 	flags = tt->flags;
628 	aclass = flags & ASN1_TFLG_TAG_CLASS;
629 
630 	p = *in;
631 	q = p;
632 
633 	if (flags & ASN1_TFLG_SK_MASK)
634 		{
635 		/* SET OF, SEQUENCE OF */
636 		int sktag, skaclass;
637 		char sk_eoc;
638 		/* First work out expected inner tag value */
639 		if (flags & ASN1_TFLG_IMPTAG)
640 			{
641 			sktag = tt->tag;
642 			skaclass = aclass;
643 			}
644 		else
645 			{
646 			skaclass = V_ASN1_UNIVERSAL;
647 			if (flags & ASN1_TFLG_SET_OF)
648 				sktag = V_ASN1_SET;
649 			else
650 				sktag = V_ASN1_SEQUENCE;
651 			}
652 		/* Get the tag */
653 		ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
654 					&p, len, sktag, skaclass, opt, ctx);
655 		if (!ret)
656 			{
657 			ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
658 						ERR_R_NESTED_ASN1_ERROR);
659 			return 0;
660 			}
661 		else if (ret == -1)
662 			return -1;
663 		if (!*val)
664 			*val = (ASN1_VALUE *)sk_new_null();
665 		else
666 			{
667 			/* We've got a valid STACK: free up any items present */
668 			STACK *sktmp = (STACK *)*val;
669 			ASN1_VALUE *vtmp;
670 			while(sk_num(sktmp) > 0)
671 				{
672 				vtmp = (ASN1_VALUE *)sk_pop(sktmp);
673 				ASN1_item_ex_free(&vtmp,
674 						ASN1_ITEM_ptr(tt->item));
675 				}
676 			}
677 
678 		if (!*val)
679 			{
680 			ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
681 						ERR_R_MALLOC_FAILURE);
682 			goto err;
683 			}
684 
685 		/* Read as many items as we can */
686 		while(len > 0)
687 			{
688 			ASN1_VALUE *skfield;
689 			q = p;
690 			/* See if EOC found */
691 			if (asn1_check_eoc(&p, len))
692 				{
693 				if (!sk_eoc)
694 					{
695 					ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
696 							ASN1_R_UNEXPECTED_EOC);
697 					goto err;
698 					}
699 				len -= p - q;
700 				sk_eoc = 0;
701 				break;
702 				}
703 			skfield = NULL;
704 			if (!ASN1_item_ex_d2i(&skfield, &p, len,
705 						ASN1_ITEM_ptr(tt->item),
706 						-1, 0, 0, ctx))
707 				{
708 				ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
709 					ERR_R_NESTED_ASN1_ERROR);
710 				goto err;
711 				}
712 			len -= p - q;
713 			if (!sk_push((STACK *)*val, (char *)skfield))
714 				{
715 				ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
716 						ERR_R_MALLOC_FAILURE);
717 				goto err;
718 				}
719 			}
720 		if (sk_eoc)
721 			{
722 			ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
723 			goto err;
724 			}
725 		}
726 	else if (flags & ASN1_TFLG_IMPTAG)
727 		{
728 		/* IMPLICIT tagging */
729 		ret = ASN1_item_ex_d2i(val, &p, len,
730 			ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
731 		if (!ret)
732 			{
733 			ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
734 						ERR_R_NESTED_ASN1_ERROR);
735 			goto err;
736 			}
737 		else if (ret == -1)
738 			return -1;
739 		}
740 	else
741 		{
742 		/* Nothing special */
743 		ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
744 							-1, 0, opt, ctx);
745 		if (!ret)
746 			{
747 			ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
748 					ERR_R_NESTED_ASN1_ERROR);
749 			goto err;
750 			}
751 		else if (ret == -1)
752 			return -1;
753 		}
754 
755 	*in = p;
756 	return 1;
757 
758 	err:
759 	ASN1_template_free(val, tt);
760 	return 0;
761 	}
762 
763 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
764 				const unsigned char **in, long inlen,
765 				const ASN1_ITEM *it,
766 				int tag, int aclass, char opt, ASN1_TLC *ctx)
767 	{
768 	int ret = 0, utype;
769 	long plen;
770 	char cst, inf, free_cont = 0;
771 	const unsigned char *p;
772 	BUF_MEM buf;
773 	const unsigned char *cont = NULL;
774 	long len;
775 	if (!pval)
776 		{
777 		ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
778 		return 0; /* Should never happen */
779 		}
780 
781 	if (it->itype == ASN1_ITYPE_MSTRING)
782 		{
783 		utype = tag;
784 		tag = -1;
785 		}
786 	else
787 		utype = it->utype;
788 
789 	if (utype == V_ASN1_ANY)
790 		{
791 		/* If type is ANY need to figure out type from tag */
792 		unsigned char oclass;
793 		if (tag >= 0)
794 			{
795 			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
796 					ASN1_R_ILLEGAL_TAGGED_ANY);
797 			return 0;
798 			}
799 		if (opt)
800 			{
801 			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
802 					ASN1_R_ILLEGAL_OPTIONAL_ANY);
803 			return 0;
804 			}
805 		p = *in;
806 		ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
807 					&p, inlen, -1, 0, 0, ctx);
808 		if (!ret)
809 			{
810 			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
811 					ERR_R_NESTED_ASN1_ERROR);
812 			return 0;
813 			}
814 		if (oclass != V_ASN1_UNIVERSAL)
815 			utype = V_ASN1_OTHER;
816 		}
817 	if (tag == -1)
818 		{
819 		tag = utype;
820 		aclass = V_ASN1_UNIVERSAL;
821 		}
822 	p = *in;
823 	/* Check header */
824 	ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
825 				&p, inlen, tag, aclass, opt, ctx);
826 	if (!ret)
827 		{
828 		ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
829 		return 0;
830 		}
831 	else if (ret == -1)
832 		return -1;
833         ret = 0;
834 	/* SEQUENCE, SET and "OTHER" are left in encoded form */
835 	if ((utype == V_ASN1_SEQUENCE)
836 		|| (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
837 		{
838 		/* Clear context cache for type OTHER because the auto clear
839 		 * when we have a exact match wont work
840 		 */
841 		if (utype == V_ASN1_OTHER)
842 			{
843 			asn1_tlc_clear(ctx);
844 			}
845 		/* SEQUENCE and SET must be constructed */
846 		else if (!cst)
847 			{
848 			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
849 				ASN1_R_TYPE_NOT_CONSTRUCTED);
850 			return 0;
851 			}
852 
853 		cont = *in;
854 		/* If indefinite length constructed find the real end */
855 		if (inf)
856 			{
857 			if (!asn1_find_end(&p, plen, inf))
858 				 goto err;
859 			len = p - cont;
860 			}
861 		else
862 			{
863 			len = p - cont + plen;
864 			p += plen;
865 			buf.data = NULL;
866 			}
867 		}
868 	else if (cst)
869 		{
870 		buf.length = 0;
871 		buf.max = 0;
872 		buf.data = NULL;
873 		/* Should really check the internal tags are correct but
874 		 * some things may get this wrong. The relevant specs
875 		 * say that constructed string types should be OCTET STRINGs
876 		 * internally irrespective of the type. So instead just check
877 		 * for UNIVERSAL class and ignore the tag.
878 		 */
879 		if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
880 			{
881 			free_cont = 1;
882 			goto err;
883 			}
884 		len = buf.length;
885 		/* Append a final null to string */
886 		if (!BUF_MEM_grow_clean(&buf, len + 1))
887 			{
888 			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
889 						ERR_R_MALLOC_FAILURE);
890 			return 0;
891 			}
892 		buf.data[len] = 0;
893 		cont = (const unsigned char *)buf.data;
894 		free_cont = 1;
895 		}
896 	else
897 		{
898 		cont = p;
899 		len = plen;
900 		p += plen;
901 		}
902 
903 	/* We now have content length and type: translate into a structure */
904 	if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
905 		goto err;
906 
907 	*in = p;
908 	ret = 1;
909 	err:
910 	if (free_cont && buf.data) OPENSSL_free(buf.data);
911 	return ret;
912 	}
913 
914 /* Translate ASN1 content octets into a structure */
915 
916 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
917 			int utype, char *free_cont, const ASN1_ITEM *it)
918 	{
919 	ASN1_VALUE **opval = NULL;
920 	ASN1_STRING *stmp;
921 	ASN1_TYPE *typ = NULL;
922 	int ret = 0;
923 	const ASN1_PRIMITIVE_FUNCS *pf;
924 	ASN1_INTEGER **tint;
925 	pf = it->funcs;
926 
927 	if (pf && pf->prim_c2i)
928 		return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
929 	/* If ANY type clear type and set pointer to internal value */
930 	if (it->utype == V_ASN1_ANY)
931 		{
932 		if (!*pval)
933 			{
934 			typ = ASN1_TYPE_new();
935 			if (typ == NULL)
936 				goto err;
937 			*pval = (ASN1_VALUE *)typ;
938 			}
939 		else
940 			typ = (ASN1_TYPE *)*pval;
941 
942 		if (utype != typ->type)
943 			ASN1_TYPE_set(typ, utype, NULL);
944 		opval = pval;
945 		pval = &typ->value.asn1_value;
946 		}
947 	switch(utype)
948 		{
949 		case V_ASN1_OBJECT:
950 		if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
951 			goto err;
952 		break;
953 
954 		case V_ASN1_NULL:
955 		if (len)
956 			{
957 			ASN1err(ASN1_F_ASN1_EX_C2I,
958 						ASN1_R_NULL_IS_WRONG_LENGTH);
959 			goto err;
960 			}
961 		*pval = (ASN1_VALUE *)1;
962 		break;
963 
964 		case V_ASN1_BOOLEAN:
965 		if (len != 1)
966 			{
967 			ASN1err(ASN1_F_ASN1_EX_C2I,
968 						ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
969 			goto err;
970 			}
971 		else
972 			{
973 			ASN1_BOOLEAN *tbool;
974 			tbool = (ASN1_BOOLEAN *)pval;
975 			*tbool = *cont;
976 			}
977 		break;
978 
979 		case V_ASN1_BIT_STRING:
980 		if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
981 			goto err;
982 		break;
983 
984 		case V_ASN1_INTEGER:
985 		case V_ASN1_NEG_INTEGER:
986 		case V_ASN1_ENUMERATED:
987 		case V_ASN1_NEG_ENUMERATED:
988 		tint = (ASN1_INTEGER **)pval;
989 		if (!c2i_ASN1_INTEGER(tint, &cont, len))
990 			goto err;
991 		/* Fixup type to match the expected form */
992 		(*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
993 		break;
994 
995 		case V_ASN1_OCTET_STRING:
996 		case V_ASN1_NUMERICSTRING:
997 		case V_ASN1_PRINTABLESTRING:
998 		case V_ASN1_T61STRING:
999 		case V_ASN1_VIDEOTEXSTRING:
1000 		case V_ASN1_IA5STRING:
1001 		case V_ASN1_UTCTIME:
1002 		case V_ASN1_GENERALIZEDTIME:
1003 		case V_ASN1_GRAPHICSTRING:
1004 		case V_ASN1_VISIBLESTRING:
1005 		case V_ASN1_GENERALSTRING:
1006 		case V_ASN1_UNIVERSALSTRING:
1007 		case V_ASN1_BMPSTRING:
1008 		case V_ASN1_UTF8STRING:
1009 		case V_ASN1_OTHER:
1010 		case V_ASN1_SET:
1011 		case V_ASN1_SEQUENCE:
1012 		default:
1013 		if (utype == V_ASN1_BMPSTRING && (len & 1))
1014 			{
1015 			ASN1err(ASN1_F_ASN1_EX_C2I,
1016 					ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
1017 			goto err;
1018 			}
1019 		if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
1020 			{
1021 			ASN1err(ASN1_F_ASN1_EX_C2I,
1022 					ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
1023 			goto err;
1024 			}
1025 		/* All based on ASN1_STRING and handled the same */
1026 		if (!*pval)
1027 			{
1028 			stmp = ASN1_STRING_type_new(utype);
1029 			if (!stmp)
1030 				{
1031 				ASN1err(ASN1_F_ASN1_EX_C2I,
1032 							ERR_R_MALLOC_FAILURE);
1033 				goto err;
1034 				}
1035 			*pval = (ASN1_VALUE *)stmp;
1036 			}
1037 		else
1038 			{
1039 			stmp = (ASN1_STRING *)*pval;
1040 			stmp->type = utype;
1041 			}
1042 		/* If we've already allocated a buffer use it */
1043 		if (*free_cont)
1044 			{
1045 			if (stmp->data)
1046 				OPENSSL_free(stmp->data);
1047 			stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1048 			stmp->length = len;
1049 			*free_cont = 0;
1050 			}
1051 		else
1052 			{
1053 			if (!ASN1_STRING_set(stmp, cont, len))
1054 				{
1055 				ASN1err(ASN1_F_ASN1_EX_C2I,
1056 							ERR_R_MALLOC_FAILURE);
1057 				ASN1_STRING_free(stmp);
1058 				*pval = NULL;
1059 				goto err;
1060 				}
1061 			}
1062 		break;
1063 		}
1064 	/* If ASN1_ANY and NULL type fix up value */
1065 	if (typ && (utype == V_ASN1_NULL))
1066 		 typ->value.ptr = NULL;
1067 
1068 	ret = 1;
1069 	err:
1070 	if (!ret)
1071 		{
1072 		ASN1_TYPE_free(typ);
1073 		if (opval)
1074 			*opval = NULL;
1075 		}
1076 	return ret;
1077 	}
1078 
1079 
1080 /* This function finds the end of an ASN1 structure when passed its maximum
1081  * length, whether it is indefinite length and a pointer to the content.
1082  * This is more efficient than calling asn1_collect because it does not
1083  * recurse on each indefinite length header.
1084  */
1085 
1086 static int asn1_find_end(const unsigned char **in, long len, char inf)
1087 	{
1088 	int expected_eoc;
1089 	long plen;
1090 	const unsigned char *p = *in, *q;
1091 	/* If not indefinite length constructed just add length */
1092 	if (inf == 0)
1093 		{
1094 		*in += len;
1095 		return 1;
1096 		}
1097 	expected_eoc = 1;
1098 	/* Indefinite length constructed form. Find the end when enough EOCs
1099 	 * are found. If more indefinite length constructed headers
1100 	 * are encountered increment the expected eoc count otherwise just
1101 	 * skip to the end of the data.
1102 	 */
1103 	while (len > 0)
1104 		{
1105 		if(asn1_check_eoc(&p, len))
1106 			{
1107 			expected_eoc--;
1108 			if (expected_eoc == 0)
1109 				break;
1110 			len -= 2;
1111 			continue;
1112 			}
1113 		q = p;
1114 		/* Just read in a header: only care about the length */
1115 		if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1116 				-1, 0, 0, NULL))
1117 			{
1118 			ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1119 			return 0;
1120 			}
1121 		if (inf)
1122 			expected_eoc++;
1123 		else
1124 			p += plen;
1125 		len -= p - q;
1126 		}
1127 	if (expected_eoc)
1128 		{
1129 		ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1130 		return 0;
1131 		}
1132 	*in = p;
1133 	return 1;
1134 	}
1135 /* This function collects the asn1 data from a constructred string
1136  * type into a buffer. The values of 'in' and 'len' should refer
1137  * to the contents of the constructed type and 'inf' should be set
1138  * if it is indefinite length.
1139  */
1140 
1141 #ifndef ASN1_MAX_STRING_NEST
1142 /* This determines how many levels of recursion are permitted in ASN1
1143  * string types. If it is not limited stack overflows can occur. If set
1144  * to zero no recursion is allowed at all. Although zero should be adequate
1145  * examples exist that require a value of 1. So 5 should be more than enough.
1146  */
1147 #define ASN1_MAX_STRING_NEST 5
1148 #endif
1149 
1150 
1151 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1152 			char inf, int tag, int aclass, int depth)
1153 	{
1154 	const unsigned char *p, *q;
1155 	long plen;
1156 	char cst, ininf;
1157 	p = *in;
1158 	inf &= 1;
1159 	/* If no buffer and not indefinite length constructed just pass over
1160 	 * the encoded data */
1161 	if (!buf && !inf)
1162 		{
1163 		*in += len;
1164 		return 1;
1165 		}
1166 	while(len > 0)
1167 		{
1168 		q = p;
1169 		/* Check for EOC */
1170 		if (asn1_check_eoc(&p, len))
1171 			{
1172 			/* EOC is illegal outside indefinite length
1173 			 * constructed form */
1174 			if (!inf)
1175 				{
1176 				ASN1err(ASN1_F_ASN1_COLLECT,
1177 					ASN1_R_UNEXPECTED_EOC);
1178 				return 0;
1179 				}
1180 			inf = 0;
1181 			break;
1182 			}
1183 
1184 		if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1185 					len, tag, aclass, 0, NULL))
1186 			{
1187 			ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1188 			return 0;
1189 			}
1190 
1191 		/* If indefinite length constructed update max length */
1192 		if (cst)
1193 			{
1194 			if (depth >= ASN1_MAX_STRING_NEST)
1195 				{
1196 				ASN1err(ASN1_F_ASN1_COLLECT,
1197 					ASN1_R_NESTED_ASN1_STRING);
1198 				return 0;
1199 				}
1200 			if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
1201 						depth + 1))
1202 				return 0;
1203 			}
1204 		else if (plen && !collect_data(buf, &p, plen))
1205 			return 0;
1206 		len -= p - q;
1207 		}
1208 	if (inf)
1209 		{
1210 		ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1211 		return 0;
1212 		}
1213 	*in = p;
1214 	return 1;
1215 	}
1216 
1217 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1218 	{
1219 	int len;
1220 	if (buf)
1221 		{
1222 		len = buf->length;
1223 		if (!BUF_MEM_grow_clean(buf, len + plen))
1224 			{
1225 			ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1226 			return 0;
1227 			}
1228 		memcpy(buf->data + len, *p, plen);
1229 		}
1230 	*p += plen;
1231 	return 1;
1232 	}
1233 
1234 /* Check for ASN1 EOC and swallow it if found */
1235 
1236 static int asn1_check_eoc(const unsigned char **in, long len)
1237 	{
1238 	const unsigned char *p;
1239 	if (len < 2) return 0;
1240 	p = *in;
1241 	if (!p[0] && !p[1])
1242 		{
1243 		*in += 2;
1244 		return 1;
1245 		}
1246 	return 0;
1247 	}
1248 
1249 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1250  * but it sets the length for indefinite length constructed
1251  * form, we don't know the exact length but we can set an
1252  * upper bound to the amount of data available minus the
1253  * header length just read.
1254  */
1255 
1256 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1257 				char *inf, char *cst,
1258 				const unsigned char **in, long len,
1259 				int exptag, int expclass, char opt,
1260 				ASN1_TLC *ctx)
1261 	{
1262 	int i;
1263 	int ptag, pclass;
1264 	long plen;
1265 	const unsigned char *p, *q;
1266 	p = *in;
1267 	q = p;
1268 
1269 	if (ctx && ctx->valid)
1270 		{
1271 		i = ctx->ret;
1272 		plen = ctx->plen;
1273 		pclass = ctx->pclass;
1274 		ptag = ctx->ptag;
1275 		p += ctx->hdrlen;
1276 		}
1277 	else
1278 		{
1279 		i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1280 		if (ctx)
1281 			{
1282 			ctx->ret = i;
1283 			ctx->plen = plen;
1284 			ctx->pclass = pclass;
1285 			ctx->ptag = ptag;
1286 			ctx->hdrlen = p - q;
1287 			ctx->valid = 1;
1288 			/* If definite length, and no error, length +
1289 			 * header can't exceed total amount of data available.
1290 			 */
1291 			if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1292 				{
1293 				ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1294 							ASN1_R_TOO_LONG);
1295 				asn1_tlc_clear(ctx);
1296 				return 0;
1297 				}
1298 			}
1299 		}
1300 
1301 	if (i & 0x80)
1302 		{
1303 		ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1304 		asn1_tlc_clear(ctx);
1305 		return 0;
1306 		}
1307 	if (exptag >= 0)
1308 		{
1309 		if ((exptag != ptag) || (expclass != pclass))
1310 			{
1311 			/* If type is OPTIONAL, not an error:
1312 			 * indicate missing type.
1313 			 */
1314 			if (opt) return -1;
1315 			asn1_tlc_clear(ctx);
1316 			ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1317 			return 0;
1318 			}
1319 		/* We have a tag and class match:
1320 		 * assume we are going to do something with it */
1321 		asn1_tlc_clear(ctx);
1322 		}
1323 
1324 	if (i & 1)
1325 		plen = len - (p - q);
1326 
1327 	if (inf)
1328 		*inf = i & 1;
1329 
1330 	if (cst)
1331 		*cst = i & V_ASN1_CONSTRUCTED;
1332 
1333 	if (olen)
1334 		*olen = plen;
1335 
1336 	if (oclass)
1337 		*oclass = pclass;
1338 
1339 	if (otag)
1340 		*otag = ptag;
1341 
1342 	*in = p;
1343 	return 1;
1344 	}
1345