tasn_dec.c revision 279264
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
68static int asn1_check_eoc(const unsigned char **in, long len);
69static int asn1_find_end(const unsigned char **in, long len, char inf);
70
71static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
72			char inf, int tag, int aclass, int depth);
73
74static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
75
76static 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
82static 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);
86static 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);
90static 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 */
96static const unsigned long tag2bit[32] = {
970,	0,	0,	B_ASN1_BIT_STRING,	/* tags  0 -  3 */
98B_ASN1_OCTET_STRING,	0,	0,		B_ASN1_UNKNOWN,/* tags  4- 7 */
99B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,	B_ASN1_UNKNOWN,/* tags  8-11 */
100B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
101B_ASN1_SEQUENCE,0,B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */
102B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING,       /* tags 20-22 */
103B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,			       /* tags 23-24 */
104B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING,  /* tags 25-27 */
105B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
106	};
107
108unsigned 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
128ASN1_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
141int 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
154int 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
532static 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
618static 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
766static 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		if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
874			|| utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
875			|| utype == V_ASN1_ENUMERATED)
876			{
877			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
878				ASN1_R_TYPE_NOT_PRIMITIVE);
879			return 0;
880			}
881		buf.length = 0;
882		buf.max = 0;
883		buf.data = NULL;
884		/* Should really check the internal tags are correct but
885		 * some things may get this wrong. The relevant specs
886		 * say that constructed string types should be OCTET STRINGs
887		 * internally irrespective of the type. So instead just check
888		 * for UNIVERSAL class and ignore the tag.
889		 */
890		if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0))
891			{
892			free_cont = 1;
893			goto err;
894			}
895		len = buf.length;
896		/* Append a final null to string */
897		if (!BUF_MEM_grow_clean(&buf, len + 1))
898			{
899			ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
900						ERR_R_MALLOC_FAILURE);
901			return 0;
902			}
903		buf.data[len] = 0;
904		cont = (const unsigned char *)buf.data;
905		free_cont = 1;
906		}
907	else
908		{
909		cont = p;
910		len = plen;
911		p += plen;
912		}
913
914	/* We now have content length and type: translate into a structure */
915	if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
916		goto err;
917
918	*in = p;
919	ret = 1;
920	err:
921	if (free_cont && buf.data) OPENSSL_free(buf.data);
922	return ret;
923	}
924
925/* Translate ASN1 content octets into a structure */
926
927int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
928			int utype, char *free_cont, const ASN1_ITEM *it)
929	{
930	ASN1_VALUE **opval = NULL;
931	ASN1_STRING *stmp;
932	ASN1_TYPE *typ = NULL;
933	int ret = 0;
934	const ASN1_PRIMITIVE_FUNCS *pf;
935	ASN1_INTEGER **tint;
936	pf = it->funcs;
937
938	if (pf && pf->prim_c2i)
939		return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
940	/* If ANY type clear type and set pointer to internal value */
941	if (it->utype == V_ASN1_ANY)
942		{
943		if (!*pval)
944			{
945			typ = ASN1_TYPE_new();
946			if (typ == NULL)
947				goto err;
948			*pval = (ASN1_VALUE *)typ;
949			}
950		else
951			typ = (ASN1_TYPE *)*pval;
952
953		if (utype != typ->type)
954			ASN1_TYPE_set(typ, utype, NULL);
955		opval = pval;
956		pval = &typ->value.asn1_value;
957		}
958	switch(utype)
959		{
960		case V_ASN1_OBJECT:
961		if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
962			goto err;
963		break;
964
965		case V_ASN1_NULL:
966		if (len)
967			{
968			ASN1err(ASN1_F_ASN1_EX_C2I,
969						ASN1_R_NULL_IS_WRONG_LENGTH);
970			goto err;
971			}
972		*pval = (ASN1_VALUE *)1;
973		break;
974
975		case V_ASN1_BOOLEAN:
976		if (len != 1)
977			{
978			ASN1err(ASN1_F_ASN1_EX_C2I,
979						ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
980			goto err;
981			}
982		else
983			{
984			ASN1_BOOLEAN *tbool;
985			tbool = (ASN1_BOOLEAN *)pval;
986			*tbool = *cont;
987			}
988		break;
989
990		case V_ASN1_BIT_STRING:
991		if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
992			goto err;
993		break;
994
995		case V_ASN1_INTEGER:
996		case V_ASN1_NEG_INTEGER:
997		case V_ASN1_ENUMERATED:
998		case V_ASN1_NEG_ENUMERATED:
999		tint = (ASN1_INTEGER **)pval;
1000		if (!c2i_ASN1_INTEGER(tint, &cont, len))
1001			goto err;
1002		/* Fixup type to match the expected form */
1003		(*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
1004		break;
1005
1006		case V_ASN1_OCTET_STRING:
1007		case V_ASN1_NUMERICSTRING:
1008		case V_ASN1_PRINTABLESTRING:
1009		case V_ASN1_T61STRING:
1010		case V_ASN1_VIDEOTEXSTRING:
1011		case V_ASN1_IA5STRING:
1012		case V_ASN1_UTCTIME:
1013		case V_ASN1_GENERALIZEDTIME:
1014		case V_ASN1_GRAPHICSTRING:
1015		case V_ASN1_VISIBLESTRING:
1016		case V_ASN1_GENERALSTRING:
1017		case V_ASN1_UNIVERSALSTRING:
1018		case V_ASN1_BMPSTRING:
1019		case V_ASN1_UTF8STRING:
1020		case V_ASN1_OTHER:
1021		case V_ASN1_SET:
1022		case V_ASN1_SEQUENCE:
1023		default:
1024		if (utype == V_ASN1_BMPSTRING && (len & 1))
1025			{
1026			ASN1err(ASN1_F_ASN1_EX_C2I,
1027					ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
1028			goto err;
1029			}
1030		if (utype == V_ASN1_UNIVERSALSTRING && (len & 3))
1031			{
1032			ASN1err(ASN1_F_ASN1_EX_C2I,
1033					ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
1034			goto err;
1035			}
1036		/* All based on ASN1_STRING and handled the same */
1037		if (!*pval)
1038			{
1039			stmp = ASN1_STRING_type_new(utype);
1040			if (!stmp)
1041				{
1042				ASN1err(ASN1_F_ASN1_EX_C2I,
1043							ERR_R_MALLOC_FAILURE);
1044				goto err;
1045				}
1046			*pval = (ASN1_VALUE *)stmp;
1047			}
1048		else
1049			{
1050			stmp = (ASN1_STRING *)*pval;
1051			stmp->type = utype;
1052			}
1053		/* If we've already allocated a buffer use it */
1054		if (*free_cont)
1055			{
1056			if (stmp->data)
1057				OPENSSL_free(stmp->data);
1058			stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1059			stmp->length = len;
1060			*free_cont = 0;
1061			}
1062		else
1063			{
1064			if (!ASN1_STRING_set(stmp, cont, len))
1065				{
1066				ASN1err(ASN1_F_ASN1_EX_C2I,
1067							ERR_R_MALLOC_FAILURE);
1068				ASN1_STRING_free(stmp);
1069				*pval = NULL;
1070				goto err;
1071				}
1072			}
1073		break;
1074		}
1075	/* If ASN1_ANY and NULL type fix up value */
1076	if (typ && (utype == V_ASN1_NULL))
1077		 typ->value.ptr = NULL;
1078
1079	ret = 1;
1080	err:
1081	if (!ret)
1082		{
1083		ASN1_TYPE_free(typ);
1084		if (opval)
1085			*opval = NULL;
1086		}
1087	return ret;
1088	}
1089
1090
1091/* This function finds the end of an ASN1 structure when passed its maximum
1092 * length, whether it is indefinite length and a pointer to the content.
1093 * This is more efficient than calling asn1_collect because it does not
1094 * recurse on each indefinite length header.
1095 */
1096
1097static int asn1_find_end(const unsigned char **in, long len, char inf)
1098	{
1099	int expected_eoc;
1100	long plen;
1101	const unsigned char *p = *in, *q;
1102	/* If not indefinite length constructed just add length */
1103	if (inf == 0)
1104		{
1105		*in += len;
1106		return 1;
1107		}
1108	expected_eoc = 1;
1109	/* Indefinite length constructed form. Find the end when enough EOCs
1110	 * are found. If more indefinite length constructed headers
1111	 * are encountered increment the expected eoc count otherwise just
1112	 * skip to the end of the data.
1113	 */
1114	while (len > 0)
1115		{
1116		if(asn1_check_eoc(&p, len))
1117			{
1118			expected_eoc--;
1119			if (expected_eoc == 0)
1120				break;
1121			len -= 2;
1122			continue;
1123			}
1124		q = p;
1125		/* Just read in a header: only care about the length */
1126		if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1127				-1, 0, 0, NULL))
1128			{
1129			ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1130			return 0;
1131			}
1132		if (inf)
1133			expected_eoc++;
1134		else
1135			p += plen;
1136		len -= p - q;
1137		}
1138	if (expected_eoc)
1139		{
1140		ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1141		return 0;
1142		}
1143	*in = p;
1144	return 1;
1145	}
1146/* This function collects the asn1 data from a constructred string
1147 * type into a buffer. The values of 'in' and 'len' should refer
1148 * to the contents of the constructed type and 'inf' should be set
1149 * if it is indefinite length.
1150 */
1151
1152#ifndef ASN1_MAX_STRING_NEST
1153/* This determines how many levels of recursion are permitted in ASN1
1154 * string types. If it is not limited stack overflows can occur. If set
1155 * to zero no recursion is allowed at all. Although zero should be adequate
1156 * examples exist that require a value of 1. So 5 should be more than enough.
1157 */
1158#define ASN1_MAX_STRING_NEST 5
1159#endif
1160
1161
1162static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1163			char inf, int tag, int aclass, int depth)
1164	{
1165	const unsigned char *p, *q;
1166	long plen;
1167	char cst, ininf;
1168	p = *in;
1169	inf &= 1;
1170	/* If no buffer and not indefinite length constructed just pass over
1171	 * the encoded data */
1172	if (!buf && !inf)
1173		{
1174		*in += len;
1175		return 1;
1176		}
1177	while(len > 0)
1178		{
1179		q = p;
1180		/* Check for EOC */
1181		if (asn1_check_eoc(&p, len))
1182			{
1183			/* EOC is illegal outside indefinite length
1184			 * constructed form */
1185			if (!inf)
1186				{
1187				ASN1err(ASN1_F_ASN1_COLLECT,
1188					ASN1_R_UNEXPECTED_EOC);
1189				return 0;
1190				}
1191			inf = 0;
1192			break;
1193			}
1194
1195		if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1196					len, tag, aclass, 0, NULL))
1197			{
1198			ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1199			return 0;
1200			}
1201
1202		/* If indefinite length constructed update max length */
1203		if (cst)
1204			{
1205			if (depth >= ASN1_MAX_STRING_NEST)
1206				{
1207				ASN1err(ASN1_F_ASN1_COLLECT,
1208					ASN1_R_NESTED_ASN1_STRING);
1209				return 0;
1210				}
1211			if (!asn1_collect(buf, &p, plen, ininf, tag, aclass,
1212						depth + 1))
1213				return 0;
1214			}
1215		else if (plen && !collect_data(buf, &p, plen))
1216			return 0;
1217		len -= p - q;
1218		}
1219	if (inf)
1220		{
1221		ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1222		return 0;
1223		}
1224	*in = p;
1225	return 1;
1226	}
1227
1228static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1229	{
1230	int len;
1231	if (buf)
1232		{
1233		len = buf->length;
1234		if (!BUF_MEM_grow_clean(buf, len + plen))
1235			{
1236			ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1237			return 0;
1238			}
1239		memcpy(buf->data + len, *p, plen);
1240		}
1241	*p += plen;
1242	return 1;
1243	}
1244
1245/* Check for ASN1 EOC and swallow it if found */
1246
1247static int asn1_check_eoc(const unsigned char **in, long len)
1248	{
1249	const unsigned char *p;
1250	if (len < 2) return 0;
1251	p = *in;
1252	if (!p[0] && !p[1])
1253		{
1254		*in += 2;
1255		return 1;
1256		}
1257	return 0;
1258	}
1259
1260/* Check an ASN1 tag and length: a bit like ASN1_get_object
1261 * but it sets the length for indefinite length constructed
1262 * form, we don't know the exact length but we can set an
1263 * upper bound to the amount of data available minus the
1264 * header length just read.
1265 */
1266
1267static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1268				char *inf, char *cst,
1269				const unsigned char **in, long len,
1270				int exptag, int expclass, char opt,
1271				ASN1_TLC *ctx)
1272	{
1273	int i;
1274	int ptag, pclass;
1275	long plen;
1276	const unsigned char *p, *q;
1277	p = *in;
1278	q = p;
1279
1280	if (ctx && ctx->valid)
1281		{
1282		i = ctx->ret;
1283		plen = ctx->plen;
1284		pclass = ctx->pclass;
1285		ptag = ctx->ptag;
1286		p += ctx->hdrlen;
1287		}
1288	else
1289		{
1290		i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1291		if (ctx)
1292			{
1293			ctx->ret = i;
1294			ctx->plen = plen;
1295			ctx->pclass = pclass;
1296			ctx->ptag = ptag;
1297			ctx->hdrlen = p - q;
1298			ctx->valid = 1;
1299			/* If definite length, and no error, length +
1300			 * header can't exceed total amount of data available.
1301			 */
1302			if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1303				{
1304				ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1305							ASN1_R_TOO_LONG);
1306				asn1_tlc_clear(ctx);
1307				return 0;
1308				}
1309			}
1310		}
1311
1312	if (i & 0x80)
1313		{
1314		ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1315		asn1_tlc_clear(ctx);
1316		return 0;
1317		}
1318	if (exptag >= 0)
1319		{
1320		if ((exptag != ptag) || (expclass != pclass))
1321			{
1322			/* If type is OPTIONAL, not an error:
1323			 * indicate missing type.
1324			 */
1325			if (opt) return -1;
1326			asn1_tlc_clear(ctx);
1327			ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1328			return 0;
1329			}
1330		/* We have a tag and class match:
1331		 * assume we are going to do something with it */
1332		asn1_tlc_clear(ctx);
1333		}
1334
1335	if (i & 1)
1336		plen = len - (p - q);
1337
1338	if (inf)
1339		*inf = i & 1;
1340
1341	if (cst)
1342		*cst = i & V_ASN1_CONSTRUCTED;
1343
1344	if (olen)
1345		*olen = plen;
1346
1347	if (oclass)
1348		*oclass = pclass;
1349
1350	if (otag)
1351		*otag = ptag;
1352
1353	*in = p;
1354	return 1;
1355	}
1356