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[thirdparty/openssl.git] / crypto / asn1 / tasn_dec.c
1 /* tasn_dec.c */
2 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) 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);
73
74 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
75
76 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
77 char *inf, char *cst,
78 const unsigned char **in, long len,
79 int exptag, int expclass, char opt,
80 ASN1_TLC *ctx);
81
82 static int asn1_template_ex_d2i(ASN1_VALUE **pval,
83 const unsigned char **in, long len,
84 const ASN1_TEMPLATE *tt, char opt,
85 ASN1_TLC *ctx);
86 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
87 const unsigned char **in, long len,
88 const ASN1_TEMPLATE *tt, char opt,
89 ASN1_TLC *ctx);
90 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
91 const unsigned char **in, long len,
92 const ASN1_ITEM *it,
93 int tag, int aclass, char opt, ASN1_TLC *ctx);
94
95 /* Table to convert tags to bit values, used for MSTRING type */
96 static const unsigned long tag2bit[32] = {
97 0, 0, 0, B_ASN1_BIT_STRING, /* tags 0 - 3 */
98 B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,/* tags 4- 7 */
99 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,/* tags 8-11 */
100 B_ASN1_UTF8STRING,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,B_ASN1_UNKNOWN,/* tags 12-15 */
101 B_ASN1_SEQUENCE,0,B_ASN1_NUMERICSTRING,B_ASN1_PRINTABLESTRING, /* tags 16-19 */
102 B_ASN1_T61STRING,B_ASN1_VIDEOTEXSTRING,B_ASN1_IA5STRING, /* tags 20-22 */
103 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, /* tags 23-24 */
104 B_ASN1_GRAPHICSTRING,B_ASN1_ISO64STRING,B_ASN1_GENERALSTRING, /* tags 25-27 */
105 B_ASN1_UNIVERSALSTRING,B_ASN1_UNKNOWN,B_ASN1_BMPSTRING,B_ASN1_UNKNOWN, /* tags 28-31 */
106 };
107
108 unsigned long ASN1_tag2bit(int tag)
109 {
110 if ((tag < 0) || (tag > 30)) return 0;
111 return tag2bit[tag];
112 }
113
114 /* Macro to initialize and invalidate the cache */
115
116 #define asn1_tlc_clear(c) if (c) (c)->valid = 0
117 /* Version to avoid compiler warning about 'c' always non-NULL */
118 #define asn1_tlc_clear_nc(c) (c)->valid = 0
119
120 /* Decode an ASN1 item, this currently behaves just
121 * like a standard 'd2i' function. 'in' points to
122 * a buffer to read the data from, in future we will
123 * have more advanced versions that can input data
124 * a piece at a time and this will simply be a special
125 * case.
126 */
127
128 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
129 const unsigned char **in, long len, const ASN1_ITEM *it)
130 {
131 ASN1_TLC c;
132 ASN1_VALUE *ptmpval = NULL;
133 if (!pval)
134 pval = &ptmpval;
135 asn1_tlc_clear_nc(&c);
136 if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
137 return *pval;
138 return NULL;
139 }
140
141 int ASN1_template_d2i(ASN1_VALUE **pval,
142 const unsigned char **in, long len, const ASN1_TEMPLATE *tt)
143 {
144 ASN1_TLC c;
145 asn1_tlc_clear_nc(&c);
146 return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
147 }
148
149
150 /* Decode an item, taking care of IMPLICIT tagging, if any.
151 * If 'opt' set and tag mismatch return -1 to handle OPTIONAL
152 */
153
154 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
155 const ASN1_ITEM *it,
156 int tag, int aclass, char opt, ASN1_TLC *ctx)
157 {
158 const ASN1_TEMPLATE *tt, *errtt = NULL;
159 const ASN1_COMPAT_FUNCS *cf;
160 const ASN1_EXTERN_FUNCS *ef;
161 const ASN1_AUX *aux = it->funcs;
162 ASN1_aux_cb *asn1_cb;
163 const unsigned char *p = NULL, *q;
164 unsigned char *wp=NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */
165 unsigned char imphack = 0, oclass;
166 char seq_eoc, seq_nolen, cst, isopt;
167 long tmplen;
168 int i;
169 int otag;
170 int ret = 0;
171 ASN1_VALUE *pchval, **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 pchval = NULL;
323 p = *in;
324 for (i = 0, tt=it->templates; i < it->tcount; i++, tt++)
325 {
326 pchptr = asn1_get_field_ptr(pval, tt);
327 /* We mark field as OPTIONAL so its absence
328 * can be recognised.
329 */
330 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
331 /* If field not present, try the next one */
332 if (ret == -1)
333 continue;
334 /* If positive return, read OK, break loop */
335 if (ret > 0)
336 break;
337 /* Otherwise must be an ASN1 parsing error */
338 errtt = tt;
339 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
340 ERR_R_NESTED_ASN1_ERROR);
341 goto err;
342 }
343
344 /* Did we fall off the end without reading anything? */
345 if (i == it->tcount)
346 {
347 /* If OPTIONAL, this is OK */
348 if (opt)
349 {
350 /* Free and zero it */
351 ASN1_item_ex_free(pval, it);
352 return -1;
353 }
354 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
355 ASN1_R_NO_MATCHING_CHOICE_TYPE);
356 goto err;
357 }
358
359 asn1_set_choice_selector(pval, i, it);
360 *in = p;
361 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
362 goto auxerr;
363 return 1;
364
365 case ASN1_ITYPE_NDEF_SEQUENCE:
366 case ASN1_ITYPE_SEQUENCE:
367 p = *in;
368 tmplen = len;
369
370 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
371 if (tag == -1)
372 {
373 tag = V_ASN1_SEQUENCE;
374 aclass = V_ASN1_UNIVERSAL;
375 }
376 /* Get SEQUENCE length and update len, p */
377 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
378 &p, len, tag, aclass, opt, ctx);
379 if (!ret)
380 {
381 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
382 ERR_R_NESTED_ASN1_ERROR);
383 goto err;
384 }
385 else if (ret == -1)
386 return -1;
387 if (aux && (aux->flags & ASN1_AFLG_BROKEN))
388 {
389 len = tmplen - (p - *in);
390 seq_nolen = 1;
391 }
392 /* If indefinite we don't do a length check */
393 else seq_nolen = seq_eoc;
394 if (!cst)
395 {
396 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
397 ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
398 goto err;
399 }
400
401 if (!*pval && !ASN1_item_ex_new(pval, it))
402 {
403 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
404 ERR_R_NESTED_ASN1_ERROR);
405 goto err;
406 }
407
408 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
409 goto auxerr;
410
411 /* Get each field entry */
412 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++)
413 {
414 const ASN1_TEMPLATE *seqtt;
415 ASN1_VALUE **pseqval;
416 seqtt = asn1_do_adb(pval, tt, 1);
417 if (!seqtt)
418 goto err;
419 pseqval = asn1_get_field_ptr(pval, seqtt);
420 /* Have we ran out of data? */
421 if (!len)
422 break;
423 q = p;
424 if (asn1_check_eoc(&p, len))
425 {
426 if (!seq_eoc)
427 {
428 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
429 ASN1_R_UNEXPECTED_EOC);
430 goto err;
431 }
432 len -= p - q;
433 seq_eoc = 0;
434 q = p;
435 break;
436 }
437 /* This determines the OPTIONAL flag value. The field
438 * cannot be omitted if it is the last of a SEQUENCE
439 * and there is still data to be read. This isn't
440 * strictly necessary but it increases efficiency in
441 * some cases.
442 */
443 if (i == (it->tcount - 1))
444 isopt = 0;
445 else isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
446 /* attempt to read in field, allowing each to be
447 * OPTIONAL */
448
449 ret = asn1_template_ex_d2i(pseqval, &p, len,
450 seqtt, isopt, ctx);
451 if (!ret)
452 {
453 errtt = seqtt;
454 goto err;
455 }
456 else if (ret == -1)
457 {
458 /* OPTIONAL component absent.
459 * Free and zero the field.
460 */
461 ASN1_template_free(pseqval, seqtt);
462 continue;
463 }
464 /* Update length */
465 len -= p - q;
466 }
467
468 /* Check for EOC if expecting one */
469 if (seq_eoc && !asn1_check_eoc(&p, len))
470 {
471 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
472 goto err;
473 }
474 /* Check all data read */
475 if (!seq_nolen && len)
476 {
477 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
478 ASN1_R_SEQUENCE_LENGTH_MISMATCH);
479 goto err;
480 }
481
482 /* If we get here we've got no more data in the SEQUENCE,
483 * however we may not have read all fields so check all
484 * remaining are OPTIONAL and clear any that are.
485 */
486 for (; i < it->tcount; tt++, i++)
487 {
488 const ASN1_TEMPLATE *seqtt;
489 seqtt = asn1_do_adb(pval, tt, 1);
490 if (!seqtt)
491 goto err;
492 if (seqtt->flags & ASN1_TFLG_OPTIONAL)
493 {
494 ASN1_VALUE **pseqval;
495 pseqval = asn1_get_field_ptr(pval, seqtt);
496 ASN1_template_free(pseqval, seqtt);
497 }
498 else
499 {
500 errtt = seqtt;
501 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
502 ASN1_R_FIELD_MISSING);
503 goto err;
504 }
505 }
506 /* Save encoding */
507 if (!asn1_enc_save(pval, *in, p - *in, it))
508 goto auxerr;
509 *in = p;
510 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
511 goto auxerr;
512 return 1;
513
514 default:
515 return 0;
516 }
517 auxerr:
518 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
519 err:
520 ASN1_item_ex_free(pval, it);
521 if (errtt)
522 ERR_add_error_data(4, "Field=", errtt->field_name,
523 ", Type=", it->sname);
524 else
525 ERR_add_error_data(2, "Type=", it->sname);
526 return 0;
527 }
528
529 /* Templates are handled with two separate functions.
530 * One handles any EXPLICIT tag and the other handles the rest.
531 */
532
533 static int asn1_template_ex_d2i(ASN1_VALUE **val,
534 const unsigned char **in, long inlen,
535 const ASN1_TEMPLATE *tt, char opt,
536 ASN1_TLC *ctx)
537 {
538 int flags, aclass;
539 int ret;
540 long len;
541 const unsigned char *p, *q;
542 char exp_eoc;
543 if (!val)
544 return 0;
545 flags = tt->flags;
546 aclass = flags & ASN1_TFLG_TAG_CLASS;
547
548 p = *in;
549
550 /* Check if EXPLICIT tag expected */
551 if (flags & ASN1_TFLG_EXPTAG)
552 {
553 char cst;
554 /* Need to work out amount of data available to the inner
555 * content and where it starts: so read in EXPLICIT header to
556 * get the info.
557 */
558 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
559 &p, inlen, tt->tag, aclass, opt, ctx);
560 q = p;
561 if (!ret)
562 {
563 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
564 ERR_R_NESTED_ASN1_ERROR);
565 return 0;
566 }
567 else if (ret == -1)
568 return -1;
569 if (!cst)
570 {
571 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
572 ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
573 return 0;
574 }
575 /* We've found the field so it can't be OPTIONAL now */
576 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
577 if (!ret)
578 {
579 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
580 ERR_R_NESTED_ASN1_ERROR);
581 return 0;
582 }
583 /* We read the field in OK so update length */
584 len -= p - q;
585 if (exp_eoc)
586 {
587 /* If NDEF we must have an EOC here */
588 if (!asn1_check_eoc(&p, len))
589 {
590 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
591 ASN1_R_MISSING_EOC);
592 goto err;
593 }
594 }
595 else
596 {
597 /* Otherwise we must hit the EXPLICIT tag end or its
598 * an error */
599 if (len)
600 {
601 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
602 ASN1_R_EXPLICIT_LENGTH_MISMATCH);
603 goto err;
604 }
605 }
606 }
607 else
608 return asn1_template_noexp_d2i(val, in, inlen,
609 tt, opt, ctx);
610
611 *in = p;
612 return 1;
613
614 err:
615 ASN1_template_free(val, tt);
616 *val = NULL;
617 return 0;
618 }
619
620 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
621 const unsigned char **in, long len,
622 const ASN1_TEMPLATE *tt, char opt,
623 ASN1_TLC *ctx)
624 {
625 int flags, aclass;
626 int ret;
627 const unsigned char *p, *q;
628 if (!val)
629 return 0;
630 flags = tt->flags;
631 aclass = flags & ASN1_TFLG_TAG_CLASS;
632
633 p = *in;
634 q = p;
635
636 if (flags & ASN1_TFLG_SK_MASK)
637 {
638 /* SET OF, SEQUENCE OF */
639 int sktag, skaclass;
640 char sk_eoc;
641 /* First work out expected inner tag value */
642 if (flags & ASN1_TFLG_IMPTAG)
643 {
644 sktag = tt->tag;
645 skaclass = aclass;
646 }
647 else
648 {
649 skaclass = V_ASN1_UNIVERSAL;
650 if (flags & ASN1_TFLG_SET_OF)
651 sktag = V_ASN1_SET;
652 else
653 sktag = V_ASN1_SEQUENCE;
654 }
655 /* Get the tag */
656 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
657 &p, len, sktag, skaclass, opt, ctx);
658 if (!ret)
659 {
660 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
661 ERR_R_NESTED_ASN1_ERROR);
662 return 0;
663 }
664 else if (ret == -1)
665 return -1;
666 if (!*val)
667 *val = (ASN1_VALUE *)sk_new_null();
668 else
669 {
670 /* We've got a valid STACK: free up any items present */
671 STACK_OF(ASN1_VALUE) *sktmp
672 = (STACK_OF(ASN1_VALUE) *)*val;
673 ASN1_VALUE *vtmp;
674 while(sk_ASN1_VALUE_num(sktmp) > 0)
675 {
676 vtmp = sk_ASN1_VALUE_pop(sktmp);
677 ASN1_item_ex_free(&vtmp,
678 ASN1_ITEM_ptr(tt->item));
679 }
680 }
681
682 if (!*val)
683 {
684 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
685 ERR_R_MALLOC_FAILURE);
686 goto err;
687 }
688
689 /* Read as many items as we can */
690 while(len > 0)
691 {
692 ASN1_VALUE *skfield;
693 q = p;
694 /* See if EOC found */
695 if (asn1_check_eoc(&p, len))
696 {
697 if (!sk_eoc)
698 {
699 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
700 ASN1_R_UNEXPECTED_EOC);
701 goto err;
702 }
703 len -= p - q;
704 sk_eoc = 0;
705 break;
706 }
707 skfield = NULL;
708 if (!ASN1_item_ex_d2i(&skfield, &p, len,
709 ASN1_ITEM_ptr(tt->item),
710 -1, 0, 0, ctx))
711 {
712 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
713 ERR_R_NESTED_ASN1_ERROR);
714 goto err;
715 }
716 len -= p - q;
717 if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val,
718 skfield))
719 {
720 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
721 ERR_R_MALLOC_FAILURE);
722 goto err;
723 }
724 }
725 if (sk_eoc)
726 {
727 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
728 goto err;
729 }
730 }
731 else if (flags & ASN1_TFLG_IMPTAG)
732 {
733 /* IMPLICIT tagging */
734 ret = ASN1_item_ex_d2i(val, &p, len,
735 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
736 if (!ret)
737 {
738 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
739 ERR_R_NESTED_ASN1_ERROR);
740 goto err;
741 }
742 else if (ret == -1)
743 return -1;
744 }
745 else
746 {
747 /* Nothing special */
748 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
749 -1, 0, opt, ctx);
750 if (!ret)
751 {
752 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
753 ERR_R_NESTED_ASN1_ERROR);
754 goto err;
755 }
756 else if (ret == -1)
757 return -1;
758 }
759
760 *in = p;
761 return 1;
762
763 err:
764 ASN1_template_free(val, tt);
765 *val = NULL;
766 return 0;
767 }
768
769 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
770 const unsigned char **in, long inlen,
771 const ASN1_ITEM *it,
772 int tag, int aclass, char opt, ASN1_TLC *ctx)
773 {
774 int ret = 0, utype;
775 long plen;
776 char cst, inf, free_cont = 0;
777 const unsigned char *p;
778 BUF_MEM buf;
779 const unsigned char *cont = NULL;
780 long len;
781 if (!pval)
782 {
783 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
784 return 0; /* Should never happen */
785 }
786
787 if (it->itype == ASN1_ITYPE_MSTRING)
788 {
789 utype = tag;
790 tag = -1;
791 }
792 else
793 utype = it->utype;
794
795 if (utype == V_ASN1_ANY)
796 {
797 /* If type is ANY need to figure out type from tag */
798 unsigned char oclass;
799 if (tag >= 0)
800 {
801 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
802 ASN1_R_ILLEGAL_TAGGED_ANY);
803 return 0;
804 }
805 if (opt)
806 {
807 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
808 ASN1_R_ILLEGAL_OPTIONAL_ANY);
809 return 0;
810 }
811 p = *in;
812 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
813 &p, inlen, -1, 0, 0, ctx);
814 if (!ret)
815 {
816 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
817 ERR_R_NESTED_ASN1_ERROR);
818 return 0;
819 }
820 if (oclass != V_ASN1_UNIVERSAL)
821 utype = V_ASN1_OTHER;
822 }
823 if (tag == -1)
824 {
825 tag = utype;
826 aclass = V_ASN1_UNIVERSAL;
827 }
828 p = *in;
829 /* Check header */
830 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
831 &p, inlen, tag, aclass, opt, ctx);
832 if (!ret)
833 {
834 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
835 return 0;
836 }
837 else if (ret == -1)
838 return -1;
839 ret = 0;
840 /* SEQUENCE, SET and "OTHER" are left in encoded form */
841 if ((utype == V_ASN1_SEQUENCE)
842 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
843 {
844 /* Clear context cache for type OTHER because the auto clear
845 * when we have a exact match wont work
846 */
847 if (utype == V_ASN1_OTHER)
848 {
849 asn1_tlc_clear(ctx);
850 }
851 /* SEQUENCE and SET must be constructed */
852 else if (!cst)
853 {
854 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
855 ASN1_R_TYPE_NOT_CONSTRUCTED);
856 return 0;
857 }
858
859 cont = *in;
860 /* If indefinite length constructed find the real end */
861 if (inf)
862 {
863 if (!asn1_find_end(&p, plen, inf))
864 goto err;
865 len = p - cont;
866 }
867 else
868 {
869 len = p - cont + plen;
870 p += plen;
871 buf.data = NULL;
872 }
873 }
874 else if (cst)
875 {
876 buf.length = 0;
877 buf.max = 0;
878 buf.data = NULL;
879 /* Should really check the internal tags are correct but
880 * some things may get this wrong. The relevant specs
881 * say that constructed string types should be OCTET STRINGs
882 * internally irrespective of the type. So instead just check
883 * for UNIVERSAL class and ignore the tag.
884 */
885 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL))
886 {
887 free_cont = 1;
888 goto err;
889 }
890 len = buf.length;
891 /* Append a final null to string */
892 if (!BUF_MEM_grow_clean(&buf, len + 1))
893 {
894 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
895 ERR_R_MALLOC_FAILURE);
896 return 0;
897 }
898 buf.data[len] = 0;
899 cont = (const unsigned char *)buf.data;
900 free_cont = 1;
901 }
902 else
903 {
904 cont = p;
905 len = plen;
906 p += plen;
907 }
908
909 /* We now have content length and type: translate into a structure */
910 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
911 goto err;
912
913 *in = p;
914 ret = 1;
915 err:
916 if (free_cont && buf.data) OPENSSL_free(buf.data);
917 return ret;
918 }
919
920 /* Translate ASN1 content octets into a structure */
921
922 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
923 int utype, char *free_cont, const ASN1_ITEM *it)
924 {
925 ASN1_VALUE **opval = NULL;
926 ASN1_STRING *stmp;
927 ASN1_TYPE *typ = NULL;
928 int ret = 0;
929 const ASN1_PRIMITIVE_FUNCS *pf;
930 ASN1_INTEGER **tint;
931 pf = it->funcs;
932
933 if (pf && pf->prim_c2i)
934 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
935 /* If ANY type clear type and set pointer to internal value */
936 if (it->utype == V_ASN1_ANY)
937 {
938 if (!*pval)
939 {
940 typ = ASN1_TYPE_new();
941 if (typ == NULL)
942 goto err;
943 *pval = (ASN1_VALUE *)typ;
944 }
945 else
946 typ = (ASN1_TYPE *)*pval;
947
948 if (utype != typ->type)
949 ASN1_TYPE_set(typ, utype, NULL);
950 opval = pval;
951 pval = &typ->value.asn1_value;
952 }
953 switch(utype)
954 {
955 case V_ASN1_OBJECT:
956 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
957 goto err;
958 break;
959
960 case V_ASN1_NULL:
961 if (len)
962 {
963 ASN1err(ASN1_F_ASN1_EX_C2I,
964 ASN1_R_NULL_IS_WRONG_LENGTH);
965 goto err;
966 }
967 *pval = (ASN1_VALUE *)1;
968 break;
969
970 case V_ASN1_BOOLEAN:
971 if (len != 1)
972 {
973 ASN1err(ASN1_F_ASN1_EX_C2I,
974 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
975 goto err;
976 }
977 else
978 {
979 ASN1_BOOLEAN *tbool;
980 tbool = (ASN1_BOOLEAN *)pval;
981 *tbool = *cont;
982 }
983 break;
984
985 case V_ASN1_BIT_STRING:
986 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
987 goto err;
988 break;
989
990 case V_ASN1_INTEGER:
991 case V_ASN1_NEG_INTEGER:
992 case V_ASN1_ENUMERATED:
993 case V_ASN1_NEG_ENUMERATED:
994 tint = (ASN1_INTEGER **)pval;
995 if (!c2i_ASN1_INTEGER(tint, &cont, len))
996 goto err;
997 /* Fixup type to match the expected form */
998 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
999 break;
1000
1001 case V_ASN1_OCTET_STRING:
1002 case V_ASN1_NUMERICSTRING:
1003 case V_ASN1_PRINTABLESTRING:
1004 case V_ASN1_T61STRING:
1005 case V_ASN1_VIDEOTEXSTRING:
1006 case V_ASN1_IA5STRING:
1007 case V_ASN1_UTCTIME:
1008 case V_ASN1_GENERALIZEDTIME:
1009 case V_ASN1_GRAPHICSTRING:
1010 case V_ASN1_VISIBLESTRING:
1011 case V_ASN1_GENERALSTRING:
1012 case V_ASN1_UNIVERSALSTRING:
1013 case V_ASN1_BMPSTRING:
1014 case V_ASN1_UTF8STRING:
1015 case V_ASN1_OTHER:
1016 case V_ASN1_SET:
1017 case V_ASN1_SEQUENCE:
1018 default:
1019 /* All based on ASN1_STRING and handled the same */
1020 if (!*pval)
1021 {
1022 stmp = ASN1_STRING_type_new(utype);
1023 if (!stmp)
1024 {
1025 ASN1err(ASN1_F_ASN1_EX_C2I,
1026 ERR_R_MALLOC_FAILURE);
1027 goto err;
1028 }
1029 *pval = (ASN1_VALUE *)stmp;
1030 }
1031 else
1032 {
1033 stmp = (ASN1_STRING *)*pval;
1034 stmp->type = utype;
1035 }
1036 /* If we've already allocated a buffer use it */
1037 if (*free_cont)
1038 {
1039 if (stmp->data)
1040 OPENSSL_free(stmp->data);
1041 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1042 stmp->length = len;
1043 *free_cont = 0;
1044 }
1045 else
1046 {
1047 if (!ASN1_STRING_set(stmp, cont, len))
1048 {
1049 ASN1err(ASN1_F_ASN1_EX_C2I,
1050 ERR_R_MALLOC_FAILURE);
1051 ASN1_STRING_free(stmp);
1052 *pval = NULL;
1053 goto err;
1054 }
1055 }
1056 break;
1057 }
1058 /* If ASN1_ANY and NULL type fix up value */
1059 if (typ && (utype == V_ASN1_NULL))
1060 typ->value.ptr = NULL;
1061
1062 ret = 1;
1063 err:
1064 if (!ret)
1065 {
1066 ASN1_TYPE_free(typ);
1067 if (opval)
1068 *opval = NULL;
1069 }
1070 return ret;
1071 }
1072
1073
1074 /* This function finds the end of an ASN1 structure when passed its maximum
1075 * length, whether it is indefinite length and a pointer to the content.
1076 * This is more efficient than calling asn1_collect because it does not
1077 * recurse on each indefinite length header.
1078 */
1079
1080 static int asn1_find_end(const unsigned char **in, long len, char inf)
1081 {
1082 int expected_eoc;
1083 long plen;
1084 const unsigned char *p = *in, *q;
1085 /* If not indefinite length constructed just add length */
1086 if (inf == 0)
1087 {
1088 *in += len;
1089 return 1;
1090 }
1091 expected_eoc = 1;
1092 /* Indefinite length constructed form. Find the end when enough EOCs
1093 * are found. If more indefinite length constructed headers
1094 * are encountered increment the expected eoc count otherwise just
1095 * skip to the end of the data.
1096 */
1097 while (len > 0)
1098 {
1099 if(asn1_check_eoc(&p, len))
1100 {
1101 expected_eoc--;
1102 if (expected_eoc == 0)
1103 break;
1104 len -= 2;
1105 continue;
1106 }
1107 q = p;
1108 /* Just read in a header: only care about the length */
1109 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1110 -1, 0, 0, NULL))
1111 {
1112 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1113 return 0;
1114 }
1115 if (inf)
1116 expected_eoc++;
1117 else
1118 p += plen;
1119 len -= p - q;
1120 }
1121 if (expected_eoc)
1122 {
1123 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1124 return 0;
1125 }
1126 *in = p;
1127 return 1;
1128 }
1129 /* This function collects the asn1 data from a constructred string
1130 * type into a buffer. The values of 'in' and 'len' should refer
1131 * to the contents of the constructed type and 'inf' should be set
1132 * if it is indefinite length.
1133 */
1134
1135 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1136 char inf, int tag, int aclass)
1137 {
1138 const unsigned char *p, *q;
1139 long plen;
1140 char cst, ininf;
1141 p = *in;
1142 inf &= 1;
1143 /* If no buffer and not indefinite length constructed just pass over
1144 * the encoded data */
1145 if (!buf && !inf)
1146 {
1147 *in += len;
1148 return 1;
1149 }
1150 while(len > 0)
1151 {
1152 q = p;
1153 /* Check for EOC */
1154 if (asn1_check_eoc(&p, len))
1155 {
1156 /* EOC is illegal outside indefinite length
1157 * constructed form */
1158 if (!inf)
1159 {
1160 ASN1err(ASN1_F_ASN1_COLLECT,
1161 ASN1_R_UNEXPECTED_EOC);
1162 return 0;
1163 }
1164 inf = 0;
1165 break;
1166 }
1167
1168 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1169 len, tag, aclass, 0, NULL))
1170 {
1171 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1172 return 0;
1173 }
1174
1175 /* If indefinite length constructed update max length */
1176 if (cst)
1177 {
1178 #ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS
1179 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
1180 return 0;
1181 #else
1182 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
1183 return 0;
1184 #endif
1185 }
1186 else if (plen && !collect_data(buf, &p, plen))
1187 return 0;
1188 len -= p - q;
1189 }
1190 if (inf)
1191 {
1192 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1193 return 0;
1194 }
1195 *in = p;
1196 return 1;
1197 }
1198
1199 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1200 {
1201 int len;
1202 if (buf)
1203 {
1204 len = buf->length;
1205 if (!BUF_MEM_grow_clean(buf, len + plen))
1206 {
1207 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1208 return 0;
1209 }
1210 memcpy(buf->data + len, *p, plen);
1211 }
1212 *p += plen;
1213 return 1;
1214 }
1215
1216 /* Check for ASN1 EOC and swallow it if found */
1217
1218 static int asn1_check_eoc(const unsigned char **in, long len)
1219 {
1220 const unsigned char *p;
1221 if (len < 2) return 0;
1222 p = *in;
1223 if (!p[0] && !p[1])
1224 {
1225 *in += 2;
1226 return 1;
1227 }
1228 return 0;
1229 }
1230
1231 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1232 * but it sets the length for indefinite length constructed
1233 * form, we don't know the exact length but we can set an
1234 * upper bound to the amount of data available minus the
1235 * header length just read.
1236 */
1237
1238 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1239 char *inf, char *cst,
1240 const unsigned char **in, long len,
1241 int exptag, int expclass, char opt,
1242 ASN1_TLC *ctx)
1243 {
1244 int i;
1245 int ptag, pclass;
1246 long plen;
1247 const unsigned char *p, *q;
1248 p = *in;
1249 q = p;
1250
1251 if (ctx && ctx->valid)
1252 {
1253 i = ctx->ret;
1254 plen = ctx->plen;
1255 pclass = ctx->pclass;
1256 ptag = ctx->ptag;
1257 p += ctx->hdrlen;
1258 }
1259 else
1260 {
1261 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1262 if (ctx)
1263 {
1264 ctx->ret = i;
1265 ctx->plen = plen;
1266 ctx->pclass = pclass;
1267 ctx->ptag = ptag;
1268 ctx->hdrlen = p - q;
1269 ctx->valid = 1;
1270 /* If definite length, and no error, length +
1271 * header can't exceed total amount of data available.
1272 */
1273 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1274 {
1275 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1276 ASN1_R_TOO_LONG);
1277 asn1_tlc_clear(ctx);
1278 return 0;
1279 }
1280 }
1281 }
1282
1283 if (i & 0x80)
1284 {
1285 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1286 asn1_tlc_clear(ctx);
1287 return 0;
1288 }
1289 if (exptag >= 0)
1290 {
1291 if ((exptag != ptag) || (expclass != pclass))
1292 {
1293 /* If type is OPTIONAL, not an error:
1294 * indicate missing type.
1295 */
1296 if (opt) return -1;
1297 asn1_tlc_clear(ctx);
1298 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1299 return 0;
1300 }
1301 /* We have a tag and class match:
1302 * assume we are going to do something with it */
1303 asn1_tlc_clear(ctx);
1304 }
1305
1306 if (i & 1)
1307 plen = len - (p - q);
1308
1309 if (inf)
1310 *inf = i & 1;
1311
1312 if (cst)
1313 *cst = i & V_ASN1_CONSTRUCTED;
1314
1315 if (olen)
1316 *olen = plen;
1317
1318 if (oclass)
1319 *oclass = pclass;
1320
1321 if (otag)
1322 *otag = ptag;
1323
1324 *in = p;
1325 return 1;
1326 }