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Fix Seg fault in DTLSv1_listen
[thirdparty/openssl.git] / crypto / asn1 / tasn_dec.c
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9d6b1ce6 1/* tasn_dec.c */
0f113f3e
MC
2/*
3 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
4 * 2000.
9d6b1ce6
DSH
5 */
6/* ====================================================================
7bdeeb64 7 * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved.
9d6b1ce6
DSH
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
0f113f3e 14 * notice, this list of conditions and the following disclaimer.
9d6b1ce6
DSH
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * licensing@OpenSSL.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 * acknowledgment:
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59
9d6b1ce6 60#include <stddef.h>
a9daa467 61#include <string.h>
9d6b1ce6
DSH
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
875a644a 68static int asn1_check_eoc(const unsigned char **in, long len);
e1cc0671 69static int asn1_find_end(const unsigned char **in, long len, char inf);
8845420f
DSH
70
71static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
0f113f3e 72 char inf, int tag, int aclass, int depth);
8845420f 73
875a644a 74static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
8845420f
DSH
75
76static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
0f113f3e
MC
77 char *inf, char *cst,
78 const unsigned char **in, long len,
79 int exptag, int expclass, char opt, ASN1_TLC *ctx);
8845420f
DSH
80
81static int asn1_template_ex_d2i(ASN1_VALUE **pval,
0f113f3e
MC
82 const unsigned char **in, long len,
83 const ASN1_TEMPLATE *tt, char opt,
84 ASN1_TLC *ctx);
8845420f 85static int asn1_template_noexp_d2i(ASN1_VALUE **val,
0f113f3e
MC
86 const unsigned char **in, long len,
87 const ASN1_TEMPLATE *tt, char opt,
88 ASN1_TLC *ctx);
8845420f 89static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
0f113f3e
MC
90 const unsigned char **in, long len,
91 const ASN1_ITEM *it,
92 int tag, int aclass, char opt,
93 ASN1_TLC *ctx);
9d6b1ce6 94
1241126a 95/* Table to convert tags to bit values, used for MSTRING type */
2d3e956a 96static const unsigned long tag2bit[32] = {
b853717f 97 /* tags 0 - 3 */
0f113f3e 98 0, 0, 0, B_ASN1_BIT_STRING,
b853717f 99 /* tags 4- 7 */
0f113f3e 100 B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN,
b853717f 101 /* tags 8-11 */
0f113f3e 102 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
b853717f 103 /* tags 12-15 */
0f113f3e 104 B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN,
b853717f 105 /* tags 16-19 */
0f113f3e 106 B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING,
b853717f 107 /* tags 20-22 */
0f113f3e 108 B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING,
b853717f 109 /* tags 23-24 */
0f113f3e 110 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME,
b853717f 111 /* tags 25-27 */
0f113f3e 112 B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING,
b853717f 113 /* tags 28-31 */
0f113f3e
MC
114 B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN,
115};
1241126a
DSH
116
117unsigned long ASN1_tag2bit(int tag)
0f113f3e
MC
118{
119 if ((tag < 0) || (tag > 30))
120 return 0;
121 return tag2bit[tag];
122}
1241126a 123
9d6b1ce6
DSH
124/* Macro to initialize and invalidate the cache */
125
0f113f3e 126#define asn1_tlc_clear(c) if (c) (c)->valid = 0
de121164 127/* Version to avoid compiler warning about 'c' always non-NULL */
0f113f3e
MC
128#define asn1_tlc_clear_nc(c) (c)->valid = 0
129
130/*
131 * Decode an ASN1 item, this currently behaves just like a standard 'd2i'
132 * function. 'in' points to a buffer to read the data from, in future we
133 * will have more advanced versions that can input data a piece at a time and
134 * this will simply be a special case.
9d6b1ce6
DSH
135 */
136
8845420f 137ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
0f113f3e
MC
138 const unsigned char **in, long len,
139 const ASN1_ITEM *it)
140{
141 ASN1_TLC c;
142 ASN1_VALUE *ptmpval = NULL;
143 if (!pval)
144 pval = &ptmpval;
145 asn1_tlc_clear_nc(&c);
146 if (ASN1_item_ex_d2i(pval, in, len, it, -1, 0, 0, &c) > 0)
147 return *pval;
148 return NULL;
149}
9d6b1ce6 150
8845420f 151int ASN1_template_d2i(ASN1_VALUE **pval,
0f113f3e
MC
152 const unsigned char **in, long len,
153 const ASN1_TEMPLATE *tt)
154{
155 ASN1_TLC c;
156 asn1_tlc_clear_nc(&c);
157 return asn1_template_ex_d2i(pval, in, len, tt, 0, &c);
158}
159
160/*
161 * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and
162 * tag mismatch return -1 to handle OPTIONAL
9d6b1ce6
DSH
163 */
164
8845420f 165int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
0f113f3e
MC
166 const ASN1_ITEM *it,
167 int tag, int aclass, char opt, ASN1_TLC *ctx)
168{
169 const ASN1_TEMPLATE *tt, *errtt = NULL;
170 const ASN1_COMPAT_FUNCS *cf;
171 const ASN1_EXTERN_FUNCS *ef;
172 const ASN1_AUX *aux = it->funcs;
173 ASN1_aux_cb *asn1_cb;
174 const unsigned char *p = NULL, *q;
175 unsigned char *wp = NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */
176 unsigned char imphack = 0, oclass;
177 char seq_eoc, seq_nolen, cst, isopt;
178 long tmplen;
179 int i;
180 int otag;
181 int ret = 0;
182 ASN1_VALUE **pchptr, *ptmpval;
183 if (!pval)
184 return 0;
185 if (aux && aux->asn1_cb)
186 asn1_cb = aux->asn1_cb;
187 else
188 asn1_cb = 0;
189
190 switch (it->itype) {
191 case ASN1_ITYPE_PRIMITIVE:
192 if (it->templates) {
193 /*
194 * tagging or OPTIONAL is currently illegal on an item template
195 * because the flags can't get passed down. In practice this
196 * isn't a problem: we include the relevant flags from the item
197 * template in the template itself.
198 */
199 if ((tag != -1) || opt) {
200 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I,
201 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
202 goto err;
203 }
204 return asn1_template_ex_d2i(pval, in, len,
205 it->templates, opt, ctx);
206 }
207 return asn1_d2i_ex_primitive(pval, in, len, it,
208 tag, aclass, opt, ctx);
0f113f3e
MC
209
210 case ASN1_ITYPE_MSTRING:
211 p = *in;
212 /* Just read in tag and class */
213 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
214 &p, len, -1, 0, 1, ctx);
215 if (!ret) {
216 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
217 goto err;
218 }
219
220 /* Must be UNIVERSAL class */
221 if (oclass != V_ASN1_UNIVERSAL) {
222 /* If OPTIONAL, assume this is OK */
223 if (opt)
224 return -1;
225 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_NOT_UNIVERSAL);
226 goto err;
227 }
228 /* Check tag matches bit map */
229 if (!(ASN1_tag2bit(otag) & it->utype)) {
230 /* If OPTIONAL, assume this is OK */
231 if (opt)
232 return -1;
233 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MSTRING_WRONG_TAG);
234 goto err;
235 }
236 return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx);
237
238 case ASN1_ITYPE_EXTERN:
239 /* Use new style d2i */
240 ef = it->funcs;
241 return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx);
242
243 case ASN1_ITYPE_COMPAT:
244 /* we must resort to old style evil hackery */
245 cf = it->funcs;
246
247 /* If OPTIONAL see if it is there */
248 if (opt) {
249 int exptag;
250 p = *in;
251 if (tag == -1)
252 exptag = it->utype;
253 else
254 exptag = tag;
255 /*
256 * Don't care about anything other than presence of expected tag
257 */
258
259 ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
260 &p, len, exptag, aclass, 1, ctx);
261 if (!ret) {
262 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
263 goto err;
264 }
265 if (ret == -1)
266 return -1;
267 }
268
269 /*
270 * This is the old style evil hack IMPLICIT handling: since the
271 * underlying code is expecting a tag and class other than the one
272 * present we change the buffer temporarily then change it back
273 * afterwards. This doesn't and never did work for tags > 30. Yes
274 * this is *horrible* but it is only needed for old style d2i which
275 * will hopefully not be around for much longer. FIXME: should copy
276 * the buffer then modify it so the input buffer can be const: we
277 * should *always* copy because the old style d2i might modify the
278 * buffer.
279 */
280
281 if (tag != -1) {
282 wp = *(unsigned char **)in;
283 imphack = *wp;
284 if (p == NULL) {
285 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
286 goto err;
287 }
288 *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
289 | it->utype);
290 }
291
292 ptmpval = cf->asn1_d2i(pval, in, len);
293
294 if (tag != -1)
295 *wp = imphack;
296
297 if (ptmpval)
298 return 1;
299
300 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
301 goto err;
302
303 case ASN1_ITYPE_CHOICE:
304 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
305 goto auxerr;
306
307 /* Allocate structure */
308 if (!*pval && !ASN1_item_ex_new(pval, it)) {
309 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
310 goto err;
311 }
312 /* CHOICE type, try each possibility in turn */
313 p = *in;
314 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
315 pchptr = asn1_get_field_ptr(pval, tt);
316 /*
317 * We mark field as OPTIONAL so its absence can be recognised.
318 */
319 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
320 /* If field not present, try the next one */
321 if (ret == -1)
322 continue;
323 /* If positive return, read OK, break loop */
324 if (ret > 0)
325 break;
326 /* Otherwise must be an ASN1 parsing error */
327 errtt = tt;
328 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
329 goto err;
330 }
331
332 /* Did we fall off the end without reading anything? */
333 if (i == it->tcount) {
334 /* If OPTIONAL, this is OK */
335 if (opt) {
336 /* Free and zero it */
337 ASN1_item_ex_free(pval, it);
338 return -1;
339 }
340 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_NO_MATCHING_CHOICE_TYPE);
341 goto err;
342 }
343
344 asn1_set_choice_selector(pval, i, it);
345 *in = p;
346 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
347 goto auxerr;
348 return 1;
349
350 case ASN1_ITYPE_NDEF_SEQUENCE:
351 case ASN1_ITYPE_SEQUENCE:
352 p = *in;
353 tmplen = len;
354
355 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
356 if (tag == -1) {
357 tag = V_ASN1_SEQUENCE;
358 aclass = V_ASN1_UNIVERSAL;
359 }
360 /* Get SEQUENCE length and update len, p */
361 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
362 &p, len, tag, aclass, opt, ctx);
363 if (!ret) {
364 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
365 goto err;
366 } else if (ret == -1)
367 return -1;
368 if (aux && (aux->flags & ASN1_AFLG_BROKEN)) {
369 len = tmplen - (p - *in);
370 seq_nolen = 1;
371 }
372 /* If indefinite we don't do a length check */
373 else
374 seq_nolen = seq_eoc;
375 if (!cst) {
376 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
377 goto err;
378 }
379
380 if (!*pval && !ASN1_item_ex_new(pval, it)) {
381 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
382 goto err;
383 }
384
385 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
386 goto auxerr;
387
388 /* Get each field entry */
389 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
390 const ASN1_TEMPLATE *seqtt;
391 ASN1_VALUE **pseqval;
392 seqtt = asn1_do_adb(pval, tt, 1);
393 if (!seqtt)
394 goto err;
395 pseqval = asn1_get_field_ptr(pval, seqtt);
396 /* Have we ran out of data? */
397 if (!len)
398 break;
399 q = p;
400 if (asn1_check_eoc(&p, len)) {
401 if (!seq_eoc) {
402 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_UNEXPECTED_EOC);
403 goto err;
404 }
405 len -= p - q;
406 seq_eoc = 0;
407 q = p;
408 break;
409 }
410 /*
411 * This determines the OPTIONAL flag value. The field cannot be
412 * omitted if it is the last of a SEQUENCE and there is still
413 * data to be read. This isn't strictly necessary but it
414 * increases efficiency in some cases.
415 */
416 if (i == (it->tcount - 1))
417 isopt = 0;
418 else
419 isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
420 /*
421 * attempt to read in field, allowing each to be OPTIONAL
422 */
423
424 ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx);
425 if (!ret) {
426 errtt = seqtt;
427 goto err;
428 } else if (ret == -1) {
429 /*
430 * OPTIONAL component absent. Free and zero the field.
431 */
432 ASN1_template_free(pseqval, seqtt);
433 continue;
434 }
435 /* Update length */
436 len -= p - q;
437 }
438
439 /* Check for EOC if expecting one */
440 if (seq_eoc && !asn1_check_eoc(&p, len)) {
441 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_MISSING_EOC);
442 goto err;
443 }
444 /* Check all data read */
445 if (!seq_nolen && len) {
446 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_SEQUENCE_LENGTH_MISMATCH);
447 goto err;
448 }
449
450 /*
451 * If we get here we've got no more data in the SEQUENCE, however we
452 * may not have read all fields so check all remaining are OPTIONAL
453 * and clear any that are.
454 */
455 for (; i < it->tcount; tt++, i++) {
456 const ASN1_TEMPLATE *seqtt;
457 seqtt = asn1_do_adb(pval, tt, 1);
458 if (!seqtt)
459 goto err;
460 if (seqtt->flags & ASN1_TFLG_OPTIONAL) {
461 ASN1_VALUE **pseqval;
462 pseqval = asn1_get_field_ptr(pval, seqtt);
463 ASN1_template_free(pseqval, seqtt);
464 } else {
465 errtt = seqtt;
466 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_FIELD_MISSING);
467 goto err;
468 }
469 }
470 /* Save encoding */
471 if (!asn1_enc_save(pval, *in, p - *in, it))
472 goto auxerr;
473 *in = p;
474 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
475 goto auxerr;
476 return 1;
477
478 default:
479 return 0;
480 }
481 auxerr:
482 ASN1err(ASN1_F_ASN1_ITEM_EX_D2I, ASN1_R_AUX_ERROR);
483 err:
484 ASN1_item_ex_free(pval, it);
485 if (errtt)
486 ERR_add_error_data(4, "Field=", errtt->field_name,
487 ", Type=", it->sname);
488 else
489 ERR_add_error_data(2, "Type=", it->sname);
490 return 0;
491}
492
493/*
494 * Templates are handled with two separate functions. One handles any
495 * EXPLICIT tag and the other handles the rest.
9d6b1ce6
DSH
496 */
497
8845420f 498static int asn1_template_ex_d2i(ASN1_VALUE **val,
0f113f3e
MC
499 const unsigned char **in, long inlen,
500 const ASN1_TEMPLATE *tt, char opt,
501 ASN1_TLC *ctx)
502{
503 int flags, aclass;
504 int ret;
505 long len;
506 const unsigned char *p, *q;
507 char exp_eoc;
508 if (!val)
509 return 0;
510 flags = tt->flags;
511 aclass = flags & ASN1_TFLG_TAG_CLASS;
512
513 p = *in;
514
515 /* Check if EXPLICIT tag expected */
516 if (flags & ASN1_TFLG_EXPTAG) {
517 char cst;
518 /*
519 * Need to work out amount of data available to the inner content and
520 * where it starts: so read in EXPLICIT header to get the info.
521 */
522 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
523 &p, inlen, tt->tag, aclass, opt, ctx);
524 q = p;
525 if (!ret) {
526 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
527 return 0;
528 } else if (ret == -1)
529 return -1;
530 if (!cst) {
531 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
532 ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
533 return 0;
534 }
535 /* We've found the field so it can't be OPTIONAL now */
536 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
537 if (!ret) {
538 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ERR_R_NESTED_ASN1_ERROR);
539 return 0;
540 }
541 /* We read the field in OK so update length */
542 len -= p - q;
543 if (exp_eoc) {
544 /* If NDEF we must have an EOC here */
545 if (!asn1_check_eoc(&p, len)) {
546 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I, ASN1_R_MISSING_EOC);
547 goto err;
548 }
549 } else {
550 /*
551 * Otherwise we must hit the EXPLICIT tag end or its an error
552 */
553 if (len) {
554 ASN1err(ASN1_F_ASN1_TEMPLATE_EX_D2I,
555 ASN1_R_EXPLICIT_LENGTH_MISMATCH);
556 goto err;
557 }
558 }
559 } else
560 return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx);
561
562 *in = p;
563 return 1;
564
565 err:
566 ASN1_template_free(val, tt);
567 return 0;
568}
9d6b1ce6 569
8845420f 570static int asn1_template_noexp_d2i(ASN1_VALUE **val,
0f113f3e
MC
571 const unsigned char **in, long len,
572 const ASN1_TEMPLATE *tt, char opt,
573 ASN1_TLC *ctx)
574{
575 int flags, aclass;
576 int ret;
577 const unsigned char *p, *q;
578 if (!val)
579 return 0;
580 flags = tt->flags;
581 aclass = flags & ASN1_TFLG_TAG_CLASS;
582
583 p = *in;
584 q = p;
585
586 if (flags & ASN1_TFLG_SK_MASK) {
587 /* SET OF, SEQUENCE OF */
588 int sktag, skaclass;
589 char sk_eoc;
590 /* First work out expected inner tag value */
591 if (flags & ASN1_TFLG_IMPTAG) {
592 sktag = tt->tag;
593 skaclass = aclass;
594 } else {
595 skaclass = V_ASN1_UNIVERSAL;
596 if (flags & ASN1_TFLG_SET_OF)
597 sktag = V_ASN1_SET;
598 else
599 sktag = V_ASN1_SEQUENCE;
600 }
601 /* Get the tag */
602 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
603 &p, len, sktag, skaclass, opt, ctx);
604 if (!ret) {
605 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
606 return 0;
607 } else if (ret == -1)
608 return -1;
609 if (!*val)
610 *val = (ASN1_VALUE *)sk_new_null();
611 else {
612 /*
613 * We've got a valid STACK: free up any items present
614 */
615 STACK_OF(ASN1_VALUE) *sktmp = (STACK_OF(ASN1_VALUE) *)*val;
616 ASN1_VALUE *vtmp;
617 while (sk_ASN1_VALUE_num(sktmp) > 0) {
618 vtmp = sk_ASN1_VALUE_pop(sktmp);
619 ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item));
620 }
621 }
622
623 if (!*val) {
624 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE);
625 goto err;
626 }
627
628 /* Read as many items as we can */
629 while (len > 0) {
630 ASN1_VALUE *skfield;
631 q = p;
632 /* See if EOC found */
633 if (asn1_check_eoc(&p, len)) {
634 if (!sk_eoc) {
635 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
636 ASN1_R_UNEXPECTED_EOC);
637 goto err;
638 }
639 len -= p - q;
640 sk_eoc = 0;
641 break;
642 }
643 skfield = NULL;
644 if (!ASN1_item_ex_d2i(&skfield, &p, len,
645 ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) {
646 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I,
647 ERR_R_NESTED_ASN1_ERROR);
648 goto err;
649 }
650 len -= p - q;
651 if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val, skfield)) {
652 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_MALLOC_FAILURE);
653 goto err;
654 }
655 }
656 if (sk_eoc) {
657 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ASN1_R_MISSING_EOC);
658 goto err;
659 }
660 } else if (flags & ASN1_TFLG_IMPTAG) {
661 /* IMPLICIT tagging */
662 ret = ASN1_item_ex_d2i(val, &p, len,
663 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt,
664 ctx);
665 if (!ret) {
666 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
667 goto err;
668 } else if (ret == -1)
669 return -1;
670 } else {
671 /* Nothing special */
672 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
673 -1, 0, opt, ctx);
674 if (!ret) {
675 ASN1err(ASN1_F_ASN1_TEMPLATE_NOEXP_D2I, ERR_R_NESTED_ASN1_ERROR);
676 goto err;
677 } else if (ret == -1)
678 return -1;
679 }
680
681 *in = p;
682 return 1;
683
684 err:
685 ASN1_template_free(val, tt);
686 return 0;
687}
9d6b1ce6 688
8845420f 689static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
0f113f3e
MC
690 const unsigned char **in, long inlen,
691 const ASN1_ITEM *it,
692 int tag, int aclass, char opt, ASN1_TLC *ctx)
693{
694 int ret = 0, utype;
695 long plen;
696 char cst, inf, free_cont = 0;
697 const unsigned char *p;
698 BUF_MEM buf;
699 const unsigned char *cont = NULL;
700 long len;
701 if (!pval) {
702 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_NULL);
703 return 0; /* Should never happen */
704 }
705
706 if (it->itype == ASN1_ITYPE_MSTRING) {
707 utype = tag;
708 tag = -1;
709 } else
710 utype = it->utype;
711
712 if (utype == V_ASN1_ANY) {
713 /* If type is ANY need to figure out type from tag */
714 unsigned char oclass;
715 if (tag >= 0) {
716 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_ILLEGAL_TAGGED_ANY);
717 return 0;
718 }
719 if (opt) {
720 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
721 ASN1_R_ILLEGAL_OPTIONAL_ANY);
722 return 0;
723 }
724 p = *in;
725 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
726 &p, inlen, -1, 0, 0, ctx);
727 if (!ret) {
728 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
729 return 0;
730 }
731 if (oclass != V_ASN1_UNIVERSAL)
732 utype = V_ASN1_OTHER;
733 }
734 if (tag == -1) {
735 tag = utype;
736 aclass = V_ASN1_UNIVERSAL;
737 }
738 p = *in;
739 /* Check header */
740 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
741 &p, inlen, tag, aclass, opt, ctx);
742 if (!ret) {
743 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_NESTED_ASN1_ERROR);
744 return 0;
745 } else if (ret == -1)
746 return -1;
747 ret = 0;
748 /* SEQUENCE, SET and "OTHER" are left in encoded form */
749 if ((utype == V_ASN1_SEQUENCE)
750 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) {
751 /*
752 * Clear context cache for type OTHER because the auto clear when we
753 * have a exact match wont work
754 */
755 if (utype == V_ASN1_OTHER) {
756 asn1_tlc_clear(ctx);
757 }
758 /* SEQUENCE and SET must be constructed */
759 else if (!cst) {
760 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE,
761 ASN1_R_TYPE_NOT_CONSTRUCTED);
762 return 0;
763 }
764
765 cont = *in;
766 /* If indefinite length constructed find the real end */
767 if (inf) {
768 if (!asn1_find_end(&p, plen, inf))
769 goto err;
770 len = p - cont;
771 } else {
772 len = p - cont + plen;
773 p += plen;
774 buf.data = NULL;
775 }
776 } else if (cst) {
777 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
778 || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
779 || utype == V_ASN1_ENUMERATED) {
780 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ASN1_R_TYPE_NOT_PRIMITIVE);
781 return 0;
782 }
783 buf.length = 0;
784 buf.max = 0;
785 buf.data = NULL;
786 /*
787 * Should really check the internal tags are correct but some things
788 * may get this wrong. The relevant specs say that constructed string
789 * types should be OCTET STRINGs internally irrespective of the type.
790 * So instead just check for UNIVERSAL class and ignore the tag.
791 */
792 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0)) {
793 free_cont = 1;
794 goto err;
795 }
796 len = buf.length;
797 /* Append a final null to string */
798 if (!BUF_MEM_grow_clean(&buf, len + 1)) {
799 ASN1err(ASN1_F_ASN1_D2I_EX_PRIMITIVE, ERR_R_MALLOC_FAILURE);
800 return 0;
801 }
802 buf.data[len] = 0;
803 cont = (const unsigned char *)buf.data;
804 free_cont = 1;
805 } else {
806 cont = p;
807 len = plen;
808 p += plen;
809 }
810
811 /* We now have content length and type: translate into a structure */
812 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
813 goto err;
814
815 *in = p;
816 ret = 1;
817 err:
818 if (free_cont && buf.data)
819 OPENSSL_free(buf.data);
820 return ret;
821}
9d6b1ce6
DSH
822
823/* Translate ASN1 content octets into a structure */
824
8845420f 825int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
0f113f3e
MC
826 int utype, char *free_cont, const ASN1_ITEM *it)
827{
828 ASN1_VALUE **opval = NULL;
829 ASN1_STRING *stmp;
830 ASN1_TYPE *typ = NULL;
831 int ret = 0;
832 const ASN1_PRIMITIVE_FUNCS *pf;
833 ASN1_INTEGER **tint;
834 pf = it->funcs;
835
836 if (pf && pf->prim_c2i)
837 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
838 /* If ANY type clear type and set pointer to internal value */
839 if (it->utype == V_ASN1_ANY) {
840 if (!*pval) {
841 typ = ASN1_TYPE_new();
842 if (typ == NULL)
843 goto err;
844 *pval = (ASN1_VALUE *)typ;
845 } else
846 typ = (ASN1_TYPE *)*pval;
847
848 if (utype != typ->type)
849 ASN1_TYPE_set(typ, utype, NULL);
850 opval = pval;
851 pval = &typ->value.asn1_value;
852 }
853 switch (utype) {
854 case V_ASN1_OBJECT:
855 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
856 goto err;
857 break;
858
859 case V_ASN1_NULL:
860 if (len) {
861 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_NULL_IS_WRONG_LENGTH);
862 goto err;
863 }
864 *pval = (ASN1_VALUE *)1;
865 break;
866
867 case V_ASN1_BOOLEAN:
868 if (len != 1) {
869 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
870 goto err;
871 } else {
872 ASN1_BOOLEAN *tbool;
873 tbool = (ASN1_BOOLEAN *)pval;
874 *tbool = *cont;
875 }
876 break;
877
878 case V_ASN1_BIT_STRING:
879 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
880 goto err;
881 break;
882
883 case V_ASN1_INTEGER:
884 case V_ASN1_NEG_INTEGER:
885 case V_ASN1_ENUMERATED:
886 case V_ASN1_NEG_ENUMERATED:
887 tint = (ASN1_INTEGER **)pval;
888 if (!c2i_ASN1_INTEGER(tint, &cont, len))
889 goto err;
890 /* Fixup type to match the expected form */
891 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
892 break;
893
894 case V_ASN1_OCTET_STRING:
895 case V_ASN1_NUMERICSTRING:
896 case V_ASN1_PRINTABLESTRING:
897 case V_ASN1_T61STRING:
898 case V_ASN1_VIDEOTEXSTRING:
899 case V_ASN1_IA5STRING:
900 case V_ASN1_UTCTIME:
901 case V_ASN1_GENERALIZEDTIME:
902 case V_ASN1_GRAPHICSTRING:
903 case V_ASN1_VISIBLESTRING:
904 case V_ASN1_GENERALSTRING:
905 case V_ASN1_UNIVERSALSTRING:
906 case V_ASN1_BMPSTRING:
907 case V_ASN1_UTF8STRING:
908 case V_ASN1_OTHER:
909 case V_ASN1_SET:
910 case V_ASN1_SEQUENCE:
911 default:
912 if (utype == V_ASN1_BMPSTRING && (len & 1)) {
913 ASN1err(ASN1_F_ASN1_EX_C2I, ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
914 goto err;
915 }
916 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) {
917 ASN1err(ASN1_F_ASN1_EX_C2I,
918 ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
919 goto err;
920 }
921 /* All based on ASN1_STRING and handled the same */
922 if (!*pval) {
923 stmp = ASN1_STRING_type_new(utype);
924 if (!stmp) {
925 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE);
926 goto err;
927 }
928 *pval = (ASN1_VALUE *)stmp;
929 } else {
930 stmp = (ASN1_STRING *)*pval;
931 stmp->type = utype;
932 }
933 /* If we've already allocated a buffer use it */
934 if (*free_cont) {
935 if (stmp->data)
936 OPENSSL_free(stmp->data);
937 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
938 stmp->length = len;
939 *free_cont = 0;
940 } else {
941 if (!ASN1_STRING_set(stmp, cont, len)) {
942 ASN1err(ASN1_F_ASN1_EX_C2I, ERR_R_MALLOC_FAILURE);
943 ASN1_STRING_free(stmp);
944 *pval = NULL;
945 goto err;
946 }
947 }
948 break;
949 }
950 /* If ASN1_ANY and NULL type fix up value */
951 if (typ && (utype == V_ASN1_NULL))
952 typ->value.ptr = NULL;
953
954 ret = 1;
955 err:
956 if (!ret) {
957 ASN1_TYPE_free(typ);
958 if (opval)
959 *opval = NULL;
960 }
961 return ret;
962}
963
964/*
965 * This function finds the end of an ASN1 structure when passed its maximum
966 * length, whether it is indefinite length and a pointer to the content. This
967 * is more efficient than calling asn1_collect because it does not recurse on
968 * each indefinite length header.
e1cc0671
DSH
969 */
970
971static int asn1_find_end(const unsigned char **in, long len, char inf)
0f113f3e
MC
972{
973 int expected_eoc;
974 long plen;
975 const unsigned char *p = *in, *q;
976 /* If not indefinite length constructed just add length */
977 if (inf == 0) {
978 *in += len;
979 return 1;
980 }
981 expected_eoc = 1;
982 /*
983 * Indefinite length constructed form. Find the end when enough EOCs are
984 * found. If more indefinite length constructed headers are encountered
985 * increment the expected eoc count otherwise just skip to the end of the
986 * data.
987 */
988 while (len > 0) {
989 if (asn1_check_eoc(&p, len)) {
990 expected_eoc--;
991 if (expected_eoc == 0)
992 break;
993 len -= 2;
994 continue;
995 }
996 q = p;
997 /* Just read in a header: only care about the length */
998 if (!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
999 -1, 0, 0, NULL)) {
1000 ASN1err(ASN1_F_ASN1_FIND_END, ERR_R_NESTED_ASN1_ERROR);
1001 return 0;
1002 }
1003 if (inf)
1004 expected_eoc++;
1005 else
1006 p += plen;
1007 len -= p - q;
1008 }
1009 if (expected_eoc) {
1010 ASN1err(ASN1_F_ASN1_FIND_END, ASN1_R_MISSING_EOC);
1011 return 0;
1012 }
1013 *in = p;
1014 return 1;
1015}
1016
1017/*
1018 * This function collects the asn1 data from a constructred string type into
1019 * a buffer. The values of 'in' and 'len' should refer to the contents of the
1020 * constructed type and 'inf' should be set if it is indefinite length.
9d6b1ce6
DSH
1021 */
1022
854a225a 1023#ifndef ASN1_MAX_STRING_NEST
0f113f3e
MC
1024/*
1025 * This determines how many levels of recursion are permitted in ASN1 string
1026 * types. If it is not limited stack overflows can occur. If set to zero no
1027 * recursion is allowed at all. Although zero should be adequate examples
1028 * exist that require a value of 1. So 5 should be more than enough.
854a225a 1029 */
0f113f3e 1030# define ASN1_MAX_STRING_NEST 5
854a225a
DSH
1031#endif
1032
8845420f 1033static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
0f113f3e
MC
1034 char inf, int tag, int aclass, int depth)
1035{
1036 const unsigned char *p, *q;
1037 long plen;
1038 char cst, ininf;
1039 p = *in;
1040 inf &= 1;
1041 /*
1042 * If no buffer and not indefinite length constructed just pass over the
1043 * encoded data
1044 */
1045 if (!buf && !inf) {
1046 *in += len;
1047 return 1;
1048 }
1049 while (len > 0) {
1050 q = p;
1051 /* Check for EOC */
1052 if (asn1_check_eoc(&p, len)) {
1053 /*
1054 * EOC is illegal outside indefinite length constructed form
1055 */
1056 if (!inf) {
1057 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_UNEXPECTED_EOC);
1058 return 0;
1059 }
1060 inf = 0;
1061 break;
1062 }
1063
1064 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1065 len, tag, aclass, 0, NULL)) {
1066 ASN1err(ASN1_F_ASN1_COLLECT, ERR_R_NESTED_ASN1_ERROR);
1067 return 0;
1068 }
1069
1070 /* If indefinite length constructed update max length */
1071 if (cst) {
1072 if (depth >= ASN1_MAX_STRING_NEST) {
1073 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_NESTED_ASN1_STRING);
1074 return 0;
1075 }
1076 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1))
1077 return 0;
1078 } else if (plen && !collect_data(buf, &p, plen))
1079 return 0;
1080 len -= p - q;
1081 }
1082 if (inf) {
1083 ASN1err(ASN1_F_ASN1_COLLECT, ASN1_R_MISSING_EOC);
1084 return 0;
1085 }
1086 *in = p;
1087 return 1;
1088}
9d6b1ce6 1089
875a644a 1090static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
0f113f3e
MC
1091{
1092 int len;
1093 if (buf) {
1094 len = buf->length;
1095 if (!BUF_MEM_grow_clean(buf, len + plen)) {
1096 ASN1err(ASN1_F_COLLECT_DATA, ERR_R_MALLOC_FAILURE);
1097 return 0;
1098 }
1099 memcpy(buf->data + len, *p, plen);
1100 }
1101 *p += plen;
1102 return 1;
1103}
9d6b1ce6
DSH
1104
1105/* Check for ASN1 EOC and swallow it if found */
1106
875a644a 1107static int asn1_check_eoc(const unsigned char **in, long len)
0f113f3e
MC
1108{
1109 const unsigned char *p;
1110 if (len < 2)
1111 return 0;
1112 p = *in;
1113 if (!p[0] && !p[1]) {
1114 *in += 2;
1115 return 1;
1116 }
1117 return 0;
1118}
1119
1120/*
1121 * Check an ASN1 tag and length: a bit like ASN1_get_object but it sets the
1122 * length for indefinite length constructed form, we don't know the exact
1123 * length but we can set an upper bound to the amount of data available minus
1124 * the header length just read.
9d6b1ce6
DSH
1125 */
1126
8845420f 1127static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
0f113f3e
MC
1128 char *inf, char *cst,
1129 const unsigned char **in, long len,
1130 int exptag, int expclass, char opt, ASN1_TLC *ctx)
1131{
1132 int i;
1133 int ptag, pclass;
1134 long plen;
1135 const unsigned char *p, *q;
1136 p = *in;
1137 q = p;
1138
1139 if (ctx && ctx->valid) {
1140 i = ctx->ret;
1141 plen = ctx->plen;
1142 pclass = ctx->pclass;
1143 ptag = ctx->ptag;
1144 p += ctx->hdrlen;
1145 } else {
1146 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1147 if (ctx) {
1148 ctx->ret = i;
1149 ctx->plen = plen;
1150 ctx->pclass = pclass;
1151 ctx->ptag = ptag;
1152 ctx->hdrlen = p - q;
1153 ctx->valid = 1;
1154 /*
1155 * If definite length, and no error, length + header can't exceed
1156 * total amount of data available.
1157 */
1158 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) {
1159 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_TOO_LONG);
1160 asn1_tlc_clear(ctx);
1161 return 0;
1162 }
1163 }
1164 }
1165
1166 if (i & 0x80) {
1167 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_BAD_OBJECT_HEADER);
1168 asn1_tlc_clear(ctx);
1169 return 0;
1170 }
1171 if (exptag >= 0) {
1172 if ((exptag != ptag) || (expclass != pclass)) {
1173 /*
1174 * If type is OPTIONAL, not an error: indicate missing type.
1175 */
1176 if (opt)
1177 return -1;
1178 asn1_tlc_clear(ctx);
1179 ASN1err(ASN1_F_ASN1_CHECK_TLEN, ASN1_R_WRONG_TAG);
1180 return 0;
1181 }
1182 /*
1183 * We have a tag and class match: assume we are going to do something
1184 * with it
1185 */
1186 asn1_tlc_clear(ctx);
1187 }
1188
1189 if (i & 1)
1190 plen = len - (p - q);
1191
1192 if (inf)
1193 *inf = i & 1;
1194
1195 if (cst)
1196 *cst = i & V_ASN1_CONSTRUCTED;
1197
1198 if (olen)
1199 *olen = plen;
1200
1201 if (oclass)
1202 *oclass = pclass;
1203
1204 if (otag)
1205 *otag = ptag;
1206
1207 *in = p;
1208 return 1;
1209}