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
ASN1_tag2bit(int tag)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
ASN1_item_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_ITEM * it)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
ASN1_template_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_TEMPLATE * tt)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
ASN1_item_ex_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_ITEM * it,int tag,int aclass,char opt,ASN1_TLC * ctx)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
asn1_template_ex_d2i(ASN1_VALUE ** val,const unsigned char ** in,long inlen,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)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 *val = NULL;
615 return 0;
616 }
617
asn1_template_noexp_d2i(ASN1_VALUE ** val,const unsigned char ** in,long len,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)618 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
619 const unsigned char **in, long len,
620 const ASN1_TEMPLATE *tt, char opt,
621 ASN1_TLC *ctx)
622 {
623 int flags, aclass;
624 int ret;
625 const unsigned char *p, *q;
626 if (!val)
627 return 0;
628 flags = tt->flags;
629 aclass = flags & ASN1_TFLG_TAG_CLASS;
630
631 p = *in;
632 q = p;
633
634 if (flags & ASN1_TFLG_SK_MASK)
635 {
636 /* SET OF, SEQUENCE OF */
637 int sktag, skaclass;
638 char sk_eoc;
639 /* First work out expected inner tag value */
640 if (flags & ASN1_TFLG_IMPTAG)
641 {
642 sktag = tt->tag;
643 skaclass = aclass;
644 }
645 else
646 {
647 skaclass = V_ASN1_UNIVERSAL;
648 if (flags & ASN1_TFLG_SET_OF)
649 sktag = V_ASN1_SET;
650 else
651 sktag = V_ASN1_SEQUENCE;
652 }
653 /* Get the tag */
654 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
655 &p, len, sktag, skaclass, opt, ctx);
656 if (!ret)
657 {
658 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
659 ERR_R_NESTED_ASN1_ERROR);
660 return 0;
661 }
662 else if (ret == -1)
663 return -1;
664 if (!*val)
665 *val = (ASN1_VALUE *)sk_new_null();
666 else
667 {
668 /* We've got a valid STACK: free up any items present */
669 STACK *sktmp = (STACK *)*val;
670 ASN1_VALUE *vtmp;
671 while(sk_num(sktmp) > 0)
672 {
673 vtmp = (ASN1_VALUE *)sk_pop(sktmp);
674 ASN1_item_ex_free(&vtmp,
675 ASN1_ITEM_ptr(tt->item));
676 }
677 }
678
679 if (!*val)
680 {
681 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
682 ERR_R_MALLOC_FAILURE);
683 goto err;
684 }
685
686 /* Read as many items as we can */
687 while(len > 0)
688 {
689 ASN1_VALUE *skfield;
690 q = p;
691 /* See if EOC found */
692 if (asn1_check_eoc(&p, len))
693 {
694 if (!sk_eoc)
695 {
696 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
697 ASN1_R_UNEXPECTED_EOC);
698 goto err;
699 }
700 len -= p - q;
701 sk_eoc = 0;
702 break;
703 }
704 skfield = NULL;
705 if (!ASN1_item_ex_d2i(&skfield, &p, len,
706 ASN1_ITEM_ptr(tt->item),
707 -1, 0, 0, ctx))
708 {
709 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
710 ERR_R_NESTED_ASN1_ERROR);
711 goto err;
712 }
713 len -= p - q;
714 if (!sk_push((STACK *)*val, (char *)skfield))
715 {
716 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
717 ERR_R_MALLOC_FAILURE);
718 goto err;
719 }
720 }
721 if (sk_eoc)
722 {
723 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
724 goto err;
725 }
726 }
727 else if (flags & ASN1_TFLG_IMPTAG)
728 {
729 /* IMPLICIT tagging */
730 ret = ASN1_item_ex_d2i(val, &p, len,
731 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt, ctx);
732 if (!ret)
733 {
734 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
735 ERR_R_NESTED_ASN1_ERROR);
736 goto err;
737 }
738 else if (ret == -1)
739 return -1;
740 }
741 else
742 {
743 /* Nothing special */
744 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
745 -1, 0, opt, ctx);
746 if (!ret)
747 {
748 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
749 ERR_R_NESTED_ASN1_ERROR);
750 goto err;
751 }
752 else if (ret == -1)
753 return -1;
754 }
755
756 *in = p;
757 return 1;
758
759 err:
760 ASN1_template_free(val, tt);
761 *val = NULL;
762 return 0;
763 }
764
asn1_d2i_ex_primitive(ASN1_VALUE ** pval,const unsigned char ** in,long inlen,const ASN1_ITEM * it,int tag,int aclass,char opt,ASN1_TLC * ctx)765 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
766 const unsigned char **in, long inlen,
767 const ASN1_ITEM *it,
768 int tag, int aclass, char opt, ASN1_TLC *ctx)
769 {
770 int ret = 0, utype;
771 long plen;
772 char cst, inf, free_cont = 0;
773 const unsigned char *p;
774 BUF_MEM buf;
775 const unsigned char *cont = NULL;
776 long len;
777 if (!pval)
778 {
779 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
780 return 0; /* Should never happen */
781 }
782
783 if (it->itype == ASN1_ITYPE_MSTRING)
784 {
785 utype = tag;
786 tag = -1;
787 }
788 else
789 utype = it->utype;
790
791 if (utype == V_ASN1_ANY)
792 {
793 /* If type is ANY need to figure out type from tag */
794 unsigned char oclass;
795 if (tag >= 0)
796 {
797 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
798 ASN1_R_ILLEGAL_TAGGED_ANY);
799 return 0;
800 }
801 if (opt)
802 {
803 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
804 ASN1_R_ILLEGAL_OPTIONAL_ANY);
805 return 0;
806 }
807 p = *in;
808 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
809 &p, inlen, -1, 0, 0, ctx);
810 if (!ret)
811 {
812 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
813 ERR_R_NESTED_ASN1_ERROR);
814 return 0;
815 }
816 if (oclass != V_ASN1_UNIVERSAL)
817 utype = V_ASN1_OTHER;
818 }
819 if (tag == -1)
820 {
821 tag = utype;
822 aclass = V_ASN1_UNIVERSAL;
823 }
824 p = *in;
825 /* Check header */
826 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
827 &p, inlen, tag, aclass, opt, ctx);
828 if (!ret)
829 {
830 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
831 return 0;
832 }
833 else if (ret == -1)
834 return -1;
835 ret = 0;
836 /* SEQUENCE, SET and "OTHER" are left in encoded form */
837 if ((utype == V_ASN1_SEQUENCE)
838 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER))
839 {
840 /* Clear context cache for type OTHER because the auto clear
841 * when we have a exact match wont work
842 */
843 if (utype == V_ASN1_OTHER)
844 {
845 asn1_tlc_clear(ctx);
846 }
847 /* SEQUENCE and SET must be constructed */
848 else if (!cst)
849 {
850 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
851 ASN1_R_TYPE_NOT_CONSTRUCTED);
852 return 0;
853 }
854
855 cont = *in;
856 /* If indefinite length constructed find the real end */
857 if (inf)
858 {
859 if (!asn1_find_end(&p, plen, inf))
860 goto err;
861 len = p - cont;
862 }
863 else
864 {
865 len = p - cont + plen;
866 p += plen;
867 buf.data = NULL;
868 }
869 }
870 else if (cst)
871 {
872 buf.length = 0;
873 buf.max = 0;
874 buf.data = NULL;
875 /* Should really check the internal tags are correct but
876 * some things may get this wrong. The relevant specs
877 * say that constructed string types should be OCTET STRINGs
878 * internally irrespective of the type. So instead just check
879 * for UNIVERSAL class and ignore the tag.
880 */
881 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL))
882 {
883 free_cont = 1;
884 goto err;
885 }
886 len = buf.length;
887 /* Append a final null to string */
888 if (!BUF_MEM_grow_clean(&buf, len + 1))
889 {
890 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
891 ERR_R_MALLOC_FAILURE);
892 return 0;
893 }
894 buf.data[len] = 0;
895 cont = (const unsigned char *)buf.data;
896 free_cont = 1;
897 }
898 else
899 {
900 cont = p;
901 len = plen;
902 p += plen;
903 }
904
905 /* We now have content length and type: translate into a structure */
906 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
907 goto err;
908
909 *in = p;
910 ret = 1;
911 err:
912 if (free_cont && buf.data) OPENSSL_free(buf.data);
913 return ret;
914 }
915
916 /* Translate ASN1 content octets into a structure */
917
asn1_ex_c2i(ASN1_VALUE ** pval,const unsigned char * cont,int len,int utype,char * free_cont,const ASN1_ITEM * it)918 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
919 int utype, char *free_cont, const ASN1_ITEM *it)
920 {
921 ASN1_VALUE **opval = NULL;
922 ASN1_STRING *stmp;
923 ASN1_TYPE *typ = NULL;
924 int ret = 0;
925 const ASN1_PRIMITIVE_FUNCS *pf;
926 ASN1_INTEGER **tint;
927 pf = it->funcs;
928
929 if (pf && pf->prim_c2i)
930 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
931 /* If ANY type clear type and set pointer to internal value */
932 if (it->utype == V_ASN1_ANY)
933 {
934 if (!*pval)
935 {
936 typ = ASN1_TYPE_new();
937 if (typ == NULL)
938 goto err;
939 *pval = (ASN1_VALUE *)typ;
940 }
941 else
942 typ = (ASN1_TYPE *)*pval;
943
944 if (utype != typ->type)
945 ASN1_TYPE_set(typ, utype, NULL);
946 opval = pval;
947 pval = &typ->value.asn1_value;
948 }
949 switch(utype)
950 {
951 case V_ASN1_OBJECT:
952 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
953 goto err;
954 break;
955
956 case V_ASN1_NULL:
957 if (len)
958 {
959 ASN1err(ASN1_F_ASN1_EX_C2I,
960 ASN1_R_NULL_IS_WRONG_LENGTH);
961 goto err;
962 }
963 *pval = (ASN1_VALUE *)1;
964 break;
965
966 case V_ASN1_BOOLEAN:
967 if (len != 1)
968 {
969 ASN1err(ASN1_F_ASN1_EX_C2I,
970 ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
971 goto err;
972 }
973 else
974 {
975 ASN1_BOOLEAN *tbool;
976 tbool = (ASN1_BOOLEAN *)pval;
977 *tbool = *cont;
978 }
979 break;
980
981 case V_ASN1_BIT_STRING:
982 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
983 goto err;
984 break;
985
986 case V_ASN1_INTEGER:
987 case V_ASN1_NEG_INTEGER:
988 case V_ASN1_ENUMERATED:
989 case V_ASN1_NEG_ENUMERATED:
990 tint = (ASN1_INTEGER **)pval;
991 if (!c2i_ASN1_INTEGER(tint, &cont, len))
992 goto err;
993 /* Fixup type to match the expected form */
994 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
995 break;
996
997 case V_ASN1_OCTET_STRING:
998 case V_ASN1_NUMERICSTRING:
999 case V_ASN1_PRINTABLESTRING:
1000 case V_ASN1_T61STRING:
1001 case V_ASN1_VIDEOTEXSTRING:
1002 case V_ASN1_IA5STRING:
1003 case V_ASN1_UTCTIME:
1004 case V_ASN1_GENERALIZEDTIME:
1005 case V_ASN1_GRAPHICSTRING:
1006 case V_ASN1_VISIBLESTRING:
1007 case V_ASN1_GENERALSTRING:
1008 case V_ASN1_UNIVERSALSTRING:
1009 case V_ASN1_BMPSTRING:
1010 case V_ASN1_UTF8STRING:
1011 case V_ASN1_OTHER:
1012 case V_ASN1_SET:
1013 case V_ASN1_SEQUENCE:
1014 default:
1015 /* All based on ASN1_STRING and handled the same */
1016 if (!*pval)
1017 {
1018 stmp = ASN1_STRING_type_new(utype);
1019 if (!stmp)
1020 {
1021 ASN1err(ASN1_F_ASN1_EX_C2I,
1022 ERR_R_MALLOC_FAILURE);
1023 goto err;
1024 }
1025 *pval = (ASN1_VALUE *)stmp;
1026 }
1027 else
1028 {
1029 stmp = (ASN1_STRING *)*pval;
1030 stmp->type = utype;
1031 }
1032 /* If we've already allocated a buffer use it */
1033 if (*free_cont)
1034 {
1035 if (stmp->data)
1036 OPENSSL_free(stmp->data);
1037 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
1038 stmp->length = len;
1039 *free_cont = 0;
1040 }
1041 else
1042 {
1043 if (!ASN1_STRING_set(stmp, cont, len))
1044 {
1045 ASN1err(ASN1_F_ASN1_EX_C2I,
1046 ERR_R_MALLOC_FAILURE);
1047 ASN1_STRING_free(stmp);
1048 *pval = NULL;
1049 goto err;
1050 }
1051 }
1052 break;
1053 }
1054 /* If ASN1_ANY and NULL type fix up value */
1055 if (typ && (utype == V_ASN1_NULL))
1056 typ->value.ptr = NULL;
1057
1058 ret = 1;
1059 err:
1060 if (!ret)
1061 {
1062 ASN1_TYPE_free(typ);
1063 if (opval)
1064 *opval = NULL;
1065 }
1066 return ret;
1067 }
1068
1069
1070 /* This function finds the end of an ASN1 structure when passed its maximum
1071 * length, whether it is indefinite length and a pointer to the content.
1072 * This is more efficient than calling asn1_collect because it does not
1073 * recurse on each indefinite length header.
1074 */
1075
asn1_find_end(const unsigned char ** in,long len,char inf)1076 static int asn1_find_end(const unsigned char **in, long len, char inf)
1077 {
1078 int expected_eoc;
1079 long plen;
1080 const unsigned char *p = *in, *q;
1081 /* If not indefinite length constructed just add length */
1082 if (inf == 0)
1083 {
1084 *in += len;
1085 return 1;
1086 }
1087 expected_eoc = 1;
1088 /* Indefinite length constructed form. Find the end when enough EOCs
1089 * are found. If more indefinite length constructed headers
1090 * are encountered increment the expected eoc count otherwise just
1091 * skip to the end of the data.
1092 */
1093 while (len > 0)
1094 {
1095 if(asn1_check_eoc(&p, len))
1096 {
1097 expected_eoc--;
1098 if (expected_eoc == 0)
1099 break;
1100 len -= 2;
1101 continue;
1102 }
1103 q = p;
1104 /* Just read in a header: only care about the length */
1105 if(!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1106 -1, 0, 0, NULL))
1107 {
1108 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1109 return 0;
1110 }
1111 if (inf)
1112 expected_eoc++;
1113 else
1114 p += plen;
1115 len -= p - q;
1116 }
1117 if (expected_eoc)
1118 {
1119 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1120 return 0;
1121 }
1122 *in = p;
1123 return 1;
1124 }
1125 /* This function collects the asn1 data from a constructred string
1126 * type into a buffer. The values of 'in' and 'len' should refer
1127 * to the contents of the constructed type and 'inf' should be set
1128 * if it is indefinite length.
1129 */
1130
asn1_collect(BUF_MEM * buf,const unsigned char ** in,long len,char inf,int tag,int aclass)1131 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1132 char inf, int tag, int aclass)
1133 {
1134 const unsigned char *p, *q;
1135 long plen;
1136 char cst, ininf;
1137 p = *in;
1138 inf &= 1;
1139 /* If no buffer and not indefinite length constructed just pass over
1140 * the encoded data */
1141 if (!buf && !inf)
1142 {
1143 *in += len;
1144 return 1;
1145 }
1146 while(len > 0)
1147 {
1148 q = p;
1149 /* Check for EOC */
1150 if (asn1_check_eoc(&p, len))
1151 {
1152 /* EOC is illegal outside indefinite length
1153 * constructed form */
1154 if (!inf)
1155 {
1156 ASN1err(ASN1_F_ASN1_COLLECT,
1157 ASN1_R_UNEXPECTED_EOC);
1158 return 0;
1159 }
1160 inf = 0;
1161 break;
1162 }
1163
1164 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1165 len, tag, aclass, 0, NULL))
1166 {
1167 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1168 return 0;
1169 }
1170
1171 /* If indefinite length constructed update max length */
1172 if (cst)
1173 {
1174 #ifdef OPENSSL_ALLOW_NESTED_ASN1_STRINGS
1175 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass))
1176 return 0;
1177 #else
1178 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
1179 return 0;
1180 #endif
1181 }
1182 else if (plen && !collect_data(buf, &p, plen))
1183 return 0;
1184 len -= p - q;
1185 }
1186 if (inf)
1187 {
1188 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1189 return 0;
1190 }
1191 *in = p;
1192 return 1;
1193 }
1194
collect_data(BUF_MEM * buf,const unsigned char ** p,long plen)1195 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1196 {
1197 int len;
1198 if (buf)
1199 {
1200 len = buf->length;
1201 if (!BUF_MEM_grow_clean(buf, len + plen))
1202 {
1203 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1204 return 0;
1205 }
1206 memcpy(buf->data + len, *p, plen);
1207 }
1208 *p += plen;
1209 return 1;
1210 }
1211
1212 /* Check for ASN1 EOC and swallow it if found */
1213
asn1_check_eoc(const unsigned char ** in,long len)1214 static int asn1_check_eoc(const unsigned char **in, long len)
1215 {
1216 const unsigned char *p;
1217 if (len < 2) return 0;
1218 p = *in;
1219 if (!p[0] && !p[1])
1220 {
1221 *in += 2;
1222 return 1;
1223 }
1224 return 0;
1225 }
1226
1227 /* Check an ASN1 tag and length: a bit like ASN1_get_object
1228 * but it sets the length for indefinite length constructed
1229 * form, we don't know the exact length but we can set an
1230 * upper bound to the amount of data available minus the
1231 * header length just read.
1232 */
1233
asn1_check_tlen(long * olen,int * otag,unsigned char * oclass,char * inf,char * cst,const unsigned char ** in,long len,int exptag,int expclass,char opt,ASN1_TLC * ctx)1234 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1235 char *inf, char *cst,
1236 const unsigned char **in, long len,
1237 int exptag, int expclass, char opt,
1238 ASN1_TLC *ctx)
1239 {
1240 int i;
1241 int ptag, pclass;
1242 long plen;
1243 const unsigned char *p, *q;
1244 p = *in;
1245 q = p;
1246
1247 if (ctx && ctx->valid)
1248 {
1249 i = ctx->ret;
1250 plen = ctx->plen;
1251 pclass = ctx->pclass;
1252 ptag = ctx->ptag;
1253 p += ctx->hdrlen;
1254 }
1255 else
1256 {
1257 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1258 if (ctx)
1259 {
1260 ctx->ret = i;
1261 ctx->plen = plen;
1262 ctx->pclass = pclass;
1263 ctx->ptag = ptag;
1264 ctx->hdrlen = p - q;
1265 ctx->valid = 1;
1266 /* If definite length, and no error, length +
1267 * header can't exceed total amount of data available.
1268 */
1269 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len))
1270 {
1271 ASN1err(ASN1_F_ASN1_CHECK_TLEN,
1272 ASN1_R_TOO_LONG);
1273 asn1_tlc_clear(ctx);
1274 return 0;
1275 }
1276 }
1277 }
1278
1279 if (i & 0x80)
1280 {
1281 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1282 asn1_tlc_clear(ctx);
1283 return 0;
1284 }
1285 if (exptag >= 0)
1286 {
1287 if ((exptag != ptag) || (expclass != pclass))
1288 {
1289 /* If type is OPTIONAL, not an error:
1290 * indicate missing type.
1291 */
1292 if (opt) return -1;
1293 asn1_tlc_clear(ctx);
1294 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1295 return 0;
1296 }
1297 /* We have a tag and class match:
1298 * assume we are going to do something with it */
1299 asn1_tlc_clear(ctx);
1300 }
1301
1302 if (i & 1)
1303 plen = len - (p - q);
1304
1305 if (inf)
1306 *inf = i & 1;
1307
1308 if (cst)
1309 *cst = i & V_ASN1_CONSTRUCTED;
1310
1311 if (olen)
1312 *olen = plen;
1313
1314 if (oclass)
1315 *oclass = pclass;
1316
1317 if (otag)
1318 *otag = ptag;
1319
1320 *in = p;
1321 return 1;
1322 }
1323