1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2 * All rights reserved.
3 *
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
7 *
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14 *
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50 * SUCH DAMAGE.
51 *
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.] */
56
57 #include <openssl/asn1.h>
58
59 #include <limits.h>
60 #include <string.h>
61
62 #include <openssl/asn1t.h>
63 #include <openssl/buf.h>
64 #include <openssl/err.h>
65 #include <openssl/mem.h>
66
67 #include "../internal.h"
68
69 static int asn1_check_eoc(const unsigned char **in, long len);
70 static int asn1_find_end(const unsigned char **in, long len, char inf);
71
72 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
73 char inf, int tag, int aclass, int depth);
74
75 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen);
76
77 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
78 char *inf, char *cst,
79 const unsigned char **in, long len,
80 int exptag, int expclass, char opt, 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,
94 ASN1_TLC *ctx);
95
96 /* Table to convert tags to bit values, used for MSTRING type */
97 static const unsigned long tag2bit[32] = {
98 0, 0, 0, B_ASN1_BIT_STRING, /* tags 0 - 3 */
99 B_ASN1_OCTET_STRING, 0, 0, B_ASN1_UNKNOWN, /* tags 4- 7 */
100 B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, /* tags
101 * 8-11 */
102 B_ASN1_UTF8STRING, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, B_ASN1_UNKNOWN, /* tags
103 * 12-15
104 */
105 B_ASN1_SEQUENCE, 0, B_ASN1_NUMERICSTRING, B_ASN1_PRINTABLESTRING, /* tags
106 * 16-19
107 */
108 B_ASN1_T61STRING, B_ASN1_VIDEOTEXSTRING, B_ASN1_IA5STRING, /* tags 20-22 */
109 B_ASN1_UTCTIME, B_ASN1_GENERALIZEDTIME, /* tags 23-24 */
110 B_ASN1_GRAPHICSTRING, B_ASN1_ISO64STRING, B_ASN1_GENERALSTRING, /* tags
111 * 25-27 */
112 B_ASN1_UNIVERSALSTRING, B_ASN1_UNKNOWN, B_ASN1_BMPSTRING, B_ASN1_UNKNOWN, /* tags
113 * 28-31
114 */
115 };
116
ASN1_tag2bit(int tag)117 unsigned long ASN1_tag2bit(int tag)
118 {
119 if ((tag < 0) || (tag > 30))
120 return 0;
121 return tag2bit[tag];
122 }
123
124 /* Macro to initialize and invalidate the cache */
125
126 #define asn1_tlc_clear(c) if (c) (c)->valid = 0
127 /* Version to avoid compiler warning about 'c' always non-NULL */
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.
135 */
136
ASN1_item_d2i(ASN1_VALUE ** pval,const unsigned char ** in,long len,const ASN1_ITEM * it)137 ASN1_VALUE *ASN1_item_d2i(ASN1_VALUE **pval,
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 }
150
151 /*
152 * Decode an item, taking care of IMPLICIT tagging, if any. If 'opt' set and
153 * tag mismatch return -1 to handle OPTIONAL
154 */
155
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)156 int ASN1_item_ex_d2i(ASN1_VALUE **pval, const unsigned char **in, long len,
157 const ASN1_ITEM *it,
158 int tag, int aclass, char opt, ASN1_TLC *ctx)
159 {
160 const ASN1_TEMPLATE *tt, *errtt = NULL;
161 const ASN1_COMPAT_FUNCS *cf;
162 const ASN1_EXTERN_FUNCS *ef;
163 const ASN1_AUX *aux = it->funcs;
164 ASN1_aux_cb *asn1_cb;
165 const unsigned char *p = NULL, *q;
166 unsigned char *wp = NULL; /* BIG FAT WARNING! BREAKS CONST WHERE USED */
167 unsigned char imphack = 0, oclass;
168 char seq_eoc, seq_nolen, cst, isopt;
169 long tmplen;
170 int i;
171 int otag;
172 int ret = 0;
173 ASN1_VALUE **pchptr, *ptmpval;
174 int combine = aclass & ASN1_TFLG_COMBINE;
175 aclass &= ~ASN1_TFLG_COMBINE;
176 if (!pval)
177 return 0;
178 if (aux && aux->asn1_cb)
179 asn1_cb = aux->asn1_cb;
180 else
181 asn1_cb = 0;
182
183 /*
184 * Bound |len| to comfortably fit in an int. Lengths in this module often
185 * switch between int and long without overflow checks.
186 */
187 if (len > INT_MAX/2) {
188 len = INT_MAX/2;
189 }
190
191 switch (it->itype) {
192 case ASN1_ITYPE_PRIMITIVE:
193 if (it->templates) {
194 /*
195 * tagging or OPTIONAL is currently illegal on an item template
196 * because the flags can't get passed down. In practice this
197 * isn't a problem: we include the relevant flags from the item
198 * template in the template itself.
199 */
200 if ((tag != -1) || opt) {
201 OPENSSL_PUT_ERROR(ASN1,
202 ASN1_R_ILLEGAL_OPTIONS_ON_ITEM_TEMPLATE);
203 goto err;
204 }
205 return asn1_template_ex_d2i(pval, in, len,
206 it->templates, opt, ctx);
207 }
208 return asn1_d2i_ex_primitive(pval, in, len, it,
209 tag, aclass, opt, ctx);
210 break;
211
212 case ASN1_ITYPE_MSTRING:
213 p = *in;
214 /* Just read in tag and class */
215 ret = asn1_check_tlen(NULL, &otag, &oclass, NULL, NULL,
216 &p, len, -1, 0, 1, ctx);
217 if (!ret) {
218 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
219 goto err;
220 }
221
222 /* Must be UNIVERSAL class */
223 if (oclass != V_ASN1_UNIVERSAL) {
224 /* If OPTIONAL, assume this is OK */
225 if (opt)
226 return -1;
227 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MSTRING_NOT_UNIVERSAL);
228 goto err;
229 }
230 /* Check tag matches bit map */
231 if (!(ASN1_tag2bit(otag) & it->utype)) {
232 /* If OPTIONAL, assume this is OK */
233 if (opt)
234 return -1;
235 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MSTRING_WRONG_TAG);
236 goto err;
237 }
238 return asn1_d2i_ex_primitive(pval, in, len, it, otag, 0, 0, ctx);
239
240 case ASN1_ITYPE_EXTERN:
241 /* Use new style d2i */
242 ef = it->funcs;
243 return ef->asn1_ex_d2i(pval, in, len, it, tag, aclass, opt, ctx);
244
245 case ASN1_ITYPE_COMPAT:
246 /* we must resort to old style evil hackery */
247 cf = it->funcs;
248
249 /* If OPTIONAL see if it is there */
250 if (opt) {
251 int exptag;
252 p = *in;
253 if (tag == -1)
254 exptag = it->utype;
255 else
256 exptag = tag;
257 /*
258 * Don't care about anything other than presence of expected tag
259 */
260
261 ret = asn1_check_tlen(NULL, NULL, NULL, NULL, NULL,
262 &p, len, exptag, aclass, 1, ctx);
263 if (!ret) {
264 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
265 goto err;
266 }
267 if (ret == -1)
268 return -1;
269 }
270
271 /*
272 * This is the old style evil hack IMPLICIT handling: since the
273 * underlying code is expecting a tag and class other than the one
274 * present we change the buffer temporarily then change it back
275 * afterwards. This doesn't and never did work for tags > 30. Yes
276 * this is *horrible* but it is only needed for old style d2i which
277 * will hopefully not be around for much longer. FIXME: should copy
278 * the buffer then modify it so the input buffer can be const: we
279 * should *always* copy because the old style d2i might modify the
280 * buffer.
281 */
282
283 if (tag != -1) {
284 wp = *(unsigned char **)in;
285 imphack = *wp;
286 if (p == NULL) {
287 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
288 goto err;
289 }
290 *wp = (unsigned char)((*p & V_ASN1_CONSTRUCTED)
291 | it->utype);
292 }
293
294 ptmpval = cf->asn1_d2i(pval, in, len);
295
296 if (tag != -1)
297 *wp = imphack;
298
299 if (ptmpval)
300 return 1;
301
302 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
303 goto err;
304
305 case ASN1_ITYPE_CHOICE:
306 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
307 goto auxerr;
308
309 if (*pval) {
310 /* Free up and zero CHOICE value if initialised */
311 i = asn1_get_choice_selector(pval, it);
312 if ((i >= 0) && (i < it->tcount)) {
313 tt = it->templates + i;
314 pchptr = asn1_get_field_ptr(pval, tt);
315 ASN1_template_free(pchptr, tt);
316 asn1_set_choice_selector(pval, -1, it);
317 }
318 } else if (!ASN1_item_ex_new(pval, it)) {
319 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
320 goto err;
321 }
322 /* CHOICE type, try each possibility in turn */
323 p = *in;
324 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
325 pchptr = asn1_get_field_ptr(pval, tt);
326 /*
327 * We mark field as OPTIONAL so its absence can be recognised.
328 */
329 ret = asn1_template_ex_d2i(pchptr, &p, len, tt, 1, ctx);
330 /* If field not present, try the next one */
331 if (ret == -1)
332 continue;
333 /* If positive return, read OK, break loop */
334 if (ret > 0)
335 break;
336 /* Otherwise must be an ASN1 parsing error */
337 errtt = tt;
338 OPENSSL_PUT_ERROR(ASN1, ASN1_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 /* If OPTIONAL, this is OK */
345 if (opt) {
346 /* Free and zero it */
347 ASN1_item_ex_free(pval, it);
348 return -1;
349 }
350 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NO_MATCHING_CHOICE_TYPE);
351 goto err;
352 }
353
354 asn1_set_choice_selector(pval, i, it);
355 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
356 goto auxerr;
357 *in = p;
358 return 1;
359
360 case ASN1_ITYPE_NDEF_SEQUENCE:
361 case ASN1_ITYPE_SEQUENCE:
362 p = *in;
363 tmplen = len;
364
365 /* If no IMPLICIT tagging set to SEQUENCE, UNIVERSAL */
366 if (tag == -1) {
367 tag = V_ASN1_SEQUENCE;
368 aclass = V_ASN1_UNIVERSAL;
369 }
370 /* Get SEQUENCE length and update len, p */
371 ret = asn1_check_tlen(&len, NULL, NULL, &seq_eoc, &cst,
372 &p, len, tag, aclass, opt, ctx);
373 if (!ret) {
374 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
375 goto err;
376 } else if (ret == -1)
377 return -1;
378 if (aux && (aux->flags & ASN1_AFLG_BROKEN)) {
379 len = tmplen - (p - *in);
380 seq_nolen = 1;
381 }
382 /* If indefinite we don't do a length check */
383 else
384 seq_nolen = seq_eoc;
385 if (!cst) {
386 OPENSSL_PUT_ERROR(ASN1, ASN1_R_SEQUENCE_NOT_CONSTRUCTED);
387 goto err;
388 }
389
390 if (!*pval && !ASN1_item_ex_new(pval, it)) {
391 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
392 goto err;
393 }
394
395 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_PRE, pval, it, NULL))
396 goto auxerr;
397
398 /* Free up and zero any ADB found */
399 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
400 if (tt->flags & ASN1_TFLG_ADB_MASK) {
401 const ASN1_TEMPLATE *seqtt;
402 ASN1_VALUE **pseqval;
403 seqtt = asn1_do_adb(pval, tt, 0);
404 if (seqtt == NULL)
405 continue;
406 pseqval = asn1_get_field_ptr(pval, seqtt);
407 ASN1_template_free(pseqval, seqtt);
408 }
409 }
410
411 /* Get each field entry */
412 for (i = 0, tt = it->templates; i < it->tcount; i++, tt++) {
413 const ASN1_TEMPLATE *seqtt;
414 ASN1_VALUE **pseqval;
415 seqtt = asn1_do_adb(pval, tt, 1);
416 if (seqtt == NULL)
417 goto err;
418 pseqval = asn1_get_field_ptr(pval, seqtt);
419 /* Have we ran out of data? */
420 if (!len)
421 break;
422 q = p;
423 if (asn1_check_eoc(&p, len)) {
424 if (!seq_eoc) {
425 OPENSSL_PUT_ERROR(ASN1, ASN1_R_UNEXPECTED_EOC);
426 goto err;
427 }
428 len -= p - q;
429 seq_eoc = 0;
430 q = p;
431 break;
432 }
433 /*
434 * This determines the OPTIONAL flag value. The field cannot be
435 * omitted if it is the last of a SEQUENCE and there is still
436 * data to be read. This isn't strictly necessary but it
437 * increases efficiency in some cases.
438 */
439 if (i == (it->tcount - 1))
440 isopt = 0;
441 else
442 isopt = (char)(seqtt->flags & ASN1_TFLG_OPTIONAL);
443 /*
444 * attempt to read in field, allowing each to be OPTIONAL
445 */
446
447 ret = asn1_template_ex_d2i(pseqval, &p, len, seqtt, isopt, ctx);
448 if (!ret) {
449 errtt = seqtt;
450 goto err;
451 } else if (ret == -1) {
452 /*
453 * OPTIONAL component absent. Free and zero the field.
454 */
455 ASN1_template_free(pseqval, seqtt);
456 continue;
457 }
458 /* Update length */
459 len -= p - q;
460 }
461
462 /* Check for EOC if expecting one */
463 if (seq_eoc && !asn1_check_eoc(&p, len)) {
464 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MISSING_EOC);
465 goto err;
466 }
467 /* Check all data read */
468 if (!seq_nolen && len) {
469 OPENSSL_PUT_ERROR(ASN1, ASN1_R_SEQUENCE_LENGTH_MISMATCH);
470 goto err;
471 }
472
473 /*
474 * If we get here we've got no more data in the SEQUENCE, however we
475 * may not have read all fields so check all remaining are OPTIONAL
476 * and clear any that are.
477 */
478 for (; i < it->tcount; tt++, i++) {
479 const ASN1_TEMPLATE *seqtt;
480 seqtt = asn1_do_adb(pval, tt, 1);
481 if (seqtt == NULL)
482 goto err;
483 if (seqtt->flags & ASN1_TFLG_OPTIONAL) {
484 ASN1_VALUE **pseqval;
485 pseqval = asn1_get_field_ptr(pval, seqtt);
486 ASN1_template_free(pseqval, seqtt);
487 } else {
488 errtt = seqtt;
489 OPENSSL_PUT_ERROR(ASN1, ASN1_R_FIELD_MISSING);
490 goto err;
491 }
492 }
493 /* Save encoding */
494 if (!asn1_enc_save(pval, *in, p - *in, it))
495 goto auxerr;
496 if (asn1_cb && !asn1_cb(ASN1_OP_D2I_POST, pval, it, NULL))
497 goto auxerr;
498 *in = p;
499 return 1;
500
501 default:
502 return 0;
503 }
504 auxerr:
505 OPENSSL_PUT_ERROR(ASN1, ASN1_R_AUX_ERROR);
506 err:
507 if (combine == 0)
508 ASN1_item_ex_free(pval, it);
509 if (errtt)
510 ERR_add_error_data(4, "Field=", errtt->field_name,
511 ", Type=", it->sname);
512 else
513 ERR_add_error_data(2, "Type=", it->sname);
514 return 0;
515 }
516
517 /*
518 * Templates are handled with two separate functions. One handles any
519 * EXPLICIT tag and the other handles the rest.
520 */
521
asn1_template_ex_d2i(ASN1_VALUE ** val,const unsigned char ** in,long inlen,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)522 static int asn1_template_ex_d2i(ASN1_VALUE **val,
523 const unsigned char **in, long inlen,
524 const ASN1_TEMPLATE *tt, char opt,
525 ASN1_TLC *ctx)
526 {
527 int flags, aclass;
528 int ret;
529 long len;
530 const unsigned char *p, *q;
531 char exp_eoc;
532 if (!val)
533 return 0;
534 flags = tt->flags;
535 aclass = flags & ASN1_TFLG_TAG_CLASS;
536
537 p = *in;
538
539 /* Check if EXPLICIT tag expected */
540 if (flags & ASN1_TFLG_EXPTAG) {
541 char cst;
542 /*
543 * Need to work out amount of data available to the inner content and
544 * where it starts: so read in EXPLICIT header to get the info.
545 */
546 ret = asn1_check_tlen(&len, NULL, NULL, &exp_eoc, &cst,
547 &p, inlen, tt->tag, aclass, opt, ctx);
548 q = p;
549 if (!ret) {
550 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
551 return 0;
552 } else if (ret == -1)
553 return -1;
554 if (!cst) {
555 OPENSSL_PUT_ERROR(ASN1, ASN1_R_EXPLICIT_TAG_NOT_CONSTRUCTED);
556 return 0;
557 }
558 /* We've found the field so it can't be OPTIONAL now */
559 ret = asn1_template_noexp_d2i(val, &p, len, tt, 0, ctx);
560 if (!ret) {
561 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
562 return 0;
563 }
564 /* We read the field in OK so update length */
565 len -= p - q;
566 if (exp_eoc) {
567 /* If NDEF we must have an EOC here */
568 if (!asn1_check_eoc(&p, len)) {
569 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MISSING_EOC);
570 goto err;
571 }
572 } else {
573 /*
574 * Otherwise we must hit the EXPLICIT tag end or its an error
575 */
576 if (len) {
577 OPENSSL_PUT_ERROR(ASN1, ASN1_R_EXPLICIT_LENGTH_MISMATCH);
578 goto err;
579 }
580 }
581 } else
582 return asn1_template_noexp_d2i(val, in, inlen, tt, opt, ctx);
583
584 *in = p;
585 return 1;
586
587 err:
588 ASN1_template_free(val, tt);
589 return 0;
590 }
591
asn1_template_noexp_d2i(ASN1_VALUE ** val,const unsigned char ** in,long len,const ASN1_TEMPLATE * tt,char opt,ASN1_TLC * ctx)592 static int asn1_template_noexp_d2i(ASN1_VALUE **val,
593 const unsigned char **in, long len,
594 const ASN1_TEMPLATE *tt, char opt,
595 ASN1_TLC *ctx)
596 {
597 int flags, aclass;
598 int ret;
599 const unsigned char *p;
600 if (!val)
601 return 0;
602 flags = tt->flags;
603 aclass = flags & ASN1_TFLG_TAG_CLASS;
604
605 p = *in;
606
607 if (flags & ASN1_TFLG_SK_MASK) {
608 /* SET OF, SEQUENCE OF */
609 int sktag, skaclass;
610 char sk_eoc;
611 /* First work out expected inner tag value */
612 if (flags & ASN1_TFLG_IMPTAG) {
613 sktag = tt->tag;
614 skaclass = aclass;
615 } else {
616 skaclass = V_ASN1_UNIVERSAL;
617 if (flags & ASN1_TFLG_SET_OF)
618 sktag = V_ASN1_SET;
619 else
620 sktag = V_ASN1_SEQUENCE;
621 }
622 /* Get the tag */
623 ret = asn1_check_tlen(&len, NULL, NULL, &sk_eoc, NULL,
624 &p, len, sktag, skaclass, opt, ctx);
625 if (!ret) {
626 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
627 return 0;
628 } else if (ret == -1)
629 return -1;
630 if (!*val)
631 *val = (ASN1_VALUE *)sk_new_null();
632 else {
633 /*
634 * We've got a valid STACK: free up any items present
635 */
636 STACK_OF(ASN1_VALUE) *sktmp = (STACK_OF(ASN1_VALUE) *)*val;
637 ASN1_VALUE *vtmp;
638 while (sk_ASN1_VALUE_num(sktmp) > 0) {
639 vtmp = sk_ASN1_VALUE_pop(sktmp);
640 ASN1_item_ex_free(&vtmp, ASN1_ITEM_ptr(tt->item));
641 }
642 }
643
644 if (!*val) {
645 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
646 goto err;
647 }
648
649 /* Read as many items as we can */
650 while (len > 0) {
651 ASN1_VALUE *skfield;
652 const unsigned char *q = p;
653 /* See if EOC found */
654 if (asn1_check_eoc(&p, len)) {
655 if (!sk_eoc) {
656 OPENSSL_PUT_ERROR(ASN1, ASN1_R_UNEXPECTED_EOC);
657 goto err;
658 }
659 len -= p - q;
660 sk_eoc = 0;
661 break;
662 }
663 skfield = NULL;
664 if (!ASN1_item_ex_d2i(&skfield, &p, len,
665 ASN1_ITEM_ptr(tt->item), -1, 0, 0, ctx)) {
666 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
667 goto err;
668 }
669 len -= p - q;
670 if (!sk_ASN1_VALUE_push((STACK_OF(ASN1_VALUE) *)*val, skfield)) {
671 ASN1_item_ex_free(&skfield, ASN1_ITEM_ptr(tt->item));
672 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
673 goto err;
674 }
675 }
676 if (sk_eoc) {
677 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MISSING_EOC);
678 goto err;
679 }
680 } else if (flags & ASN1_TFLG_IMPTAG) {
681 /* IMPLICIT tagging */
682 ret = ASN1_item_ex_d2i(val, &p, len,
683 ASN1_ITEM_ptr(tt->item), tt->tag, aclass, opt,
684 ctx);
685 if (!ret) {
686 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
687 goto err;
688 } else if (ret == -1)
689 return -1;
690 } else {
691 /* Nothing special */
692 ret = ASN1_item_ex_d2i(val, &p, len, ASN1_ITEM_ptr(tt->item),
693 -1, tt->flags & ASN1_TFLG_COMBINE, opt, ctx);
694 if (!ret) {
695 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
696 goto err;
697 } else if (ret == -1)
698 return -1;
699 }
700
701 *in = p;
702 return 1;
703
704 err:
705 ASN1_template_free(val, tt);
706 return 0;
707 }
708
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)709 static int asn1_d2i_ex_primitive(ASN1_VALUE **pval,
710 const unsigned char **in, long inlen,
711 const ASN1_ITEM *it,
712 int tag, int aclass, char opt, ASN1_TLC *ctx)
713 {
714 int ret = 0, utype;
715 long plen;
716 char cst, inf, free_cont = 0;
717 const unsigned char *p;
718 BUF_MEM buf = {0, NULL, 0 };
719 const unsigned char *cont = NULL;
720 long len;
721 if (!pval) {
722 OPENSSL_PUT_ERROR(ASN1, ASN1_R_ILLEGAL_NULL);
723 return 0; /* Should never happen */
724 }
725
726 if (it->itype == ASN1_ITYPE_MSTRING) {
727 utype = tag;
728 tag = -1;
729 } else
730 utype = it->utype;
731
732 if (utype == V_ASN1_ANY) {
733 /* If type is ANY need to figure out type from tag */
734 unsigned char oclass;
735 if (tag >= 0) {
736 OPENSSL_PUT_ERROR(ASN1, ASN1_R_ILLEGAL_TAGGED_ANY);
737 return 0;
738 }
739 if (opt) {
740 OPENSSL_PUT_ERROR(ASN1, ASN1_R_ILLEGAL_OPTIONAL_ANY);
741 return 0;
742 }
743 p = *in;
744 ret = asn1_check_tlen(NULL, &utype, &oclass, NULL, NULL,
745 &p, inlen, -1, 0, 0, ctx);
746 if (!ret) {
747 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
748 return 0;
749 }
750 if (oclass != V_ASN1_UNIVERSAL)
751 utype = V_ASN1_OTHER;
752 }
753 if (tag == -1) {
754 tag = utype;
755 aclass = V_ASN1_UNIVERSAL;
756 }
757 p = *in;
758 /* Check header */
759 ret = asn1_check_tlen(&plen, NULL, NULL, &inf, &cst,
760 &p, inlen, tag, aclass, opt, ctx);
761 if (!ret) {
762 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
763 return 0;
764 } else if (ret == -1)
765 return -1;
766 ret = 0;
767 /* SEQUENCE, SET and "OTHER" are left in encoded form */
768 if ((utype == V_ASN1_SEQUENCE)
769 || (utype == V_ASN1_SET) || (utype == V_ASN1_OTHER)) {
770 /*
771 * Clear context cache for type OTHER because the auto clear when we
772 * have a exact match wont work
773 */
774 if (utype == V_ASN1_OTHER) {
775 asn1_tlc_clear(ctx);
776 }
777 /* SEQUENCE and SET must be constructed */
778 else if (!cst) {
779 OPENSSL_PUT_ERROR(ASN1, ASN1_R_TYPE_NOT_CONSTRUCTED);
780 return 0;
781 }
782
783 cont = *in;
784 /* If indefinite length constructed find the real end */
785 if (inf) {
786 if (!asn1_find_end(&p, plen, inf))
787 goto err;
788 len = p - cont;
789 } else {
790 len = p - cont + plen;
791 p += plen;
792 }
793 } else if (cst) {
794 if (utype == V_ASN1_NULL || utype == V_ASN1_BOOLEAN
795 || utype == V_ASN1_OBJECT || utype == V_ASN1_INTEGER
796 || utype == V_ASN1_ENUMERATED) {
797 /* These types only have primitive encodings. */
798 OPENSSL_PUT_ERROR(ASN1, ASN1_R_TYPE_NOT_PRIMITIVE);
799 return 0;
800 }
801
802 /* Free any returned 'buf' content */
803 free_cont = 1;
804 /*
805 * Should really check the internal tags are correct but some things
806 * may get this wrong. The relevant specs say that constructed string
807 * types should be OCTET STRINGs internally irrespective of the type.
808 * So instead just check for UNIVERSAL class and ignore the tag.
809 */
810 if (!asn1_collect(&buf, &p, plen, inf, -1, V_ASN1_UNIVERSAL, 0)) {
811 goto err;
812 }
813 len = buf.length;
814 /* Append a final null to string */
815 if (!BUF_MEM_grow_clean(&buf, len + 1)) {
816 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
817 goto err;
818 }
819 buf.data[len] = 0;
820 cont = (const unsigned char *)buf.data;
821 } else {
822 cont = p;
823 len = plen;
824 p += plen;
825 }
826
827 /* We now have content length and type: translate into a structure */
828 /* asn1_ex_c2i may reuse allocated buffer, and so sets free_cont to 0 */
829 if (!asn1_ex_c2i(pval, cont, len, utype, &free_cont, it))
830 goto err;
831
832 *in = p;
833 ret = 1;
834 err:
835 if (free_cont && buf.data)
836 OPENSSL_free(buf.data);
837 return ret;
838 }
839
840 /* Translate ASN1 content octets into a structure */
841
asn1_ex_c2i(ASN1_VALUE ** pval,const unsigned char * cont,int len,int utype,char * free_cont,const ASN1_ITEM * it)842 int asn1_ex_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
843 int utype, char *free_cont, const ASN1_ITEM *it)
844 {
845 ASN1_VALUE **opval = NULL;
846 ASN1_STRING *stmp;
847 ASN1_TYPE *typ = NULL;
848 int ret = 0;
849 const ASN1_PRIMITIVE_FUNCS *pf;
850 ASN1_INTEGER **tint;
851 pf = it->funcs;
852
853 if (pf && pf->prim_c2i)
854 return pf->prim_c2i(pval, cont, len, utype, free_cont, it);
855 /* If ANY type clear type and set pointer to internal value */
856 if (it->utype == V_ASN1_ANY) {
857 if (!*pval) {
858 typ = ASN1_TYPE_new();
859 if (typ == NULL)
860 goto err;
861 *pval = (ASN1_VALUE *)typ;
862 } else
863 typ = (ASN1_TYPE *)*pval;
864
865 if (utype != typ->type)
866 ASN1_TYPE_set(typ, utype, NULL);
867 opval = pval;
868 pval = &typ->value.asn1_value;
869 }
870 switch (utype) {
871 case V_ASN1_OBJECT:
872 if (!c2i_ASN1_OBJECT((ASN1_OBJECT **)pval, &cont, len))
873 goto err;
874 break;
875
876 case V_ASN1_NULL:
877 if (len) {
878 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NULL_IS_WRONG_LENGTH);
879 goto err;
880 }
881 *pval = (ASN1_VALUE *)1;
882 break;
883
884 case V_ASN1_BOOLEAN:
885 if (len != 1) {
886 OPENSSL_PUT_ERROR(ASN1, ASN1_R_BOOLEAN_IS_WRONG_LENGTH);
887 goto err;
888 } else {
889 ASN1_BOOLEAN *tbool;
890 tbool = (ASN1_BOOLEAN *)pval;
891 *tbool = *cont;
892 }
893 break;
894
895 case V_ASN1_BIT_STRING:
896 if (!c2i_ASN1_BIT_STRING((ASN1_BIT_STRING **)pval, &cont, len))
897 goto err;
898 break;
899
900 case V_ASN1_INTEGER:
901 case V_ASN1_ENUMERATED:
902 tint = (ASN1_INTEGER **)pval;
903 if (!c2i_ASN1_INTEGER(tint, &cont, len))
904 goto err;
905 /* Fixup type to match the expected form */
906 (*tint)->type = utype | ((*tint)->type & V_ASN1_NEG);
907 break;
908
909 case V_ASN1_OCTET_STRING:
910 case V_ASN1_NUMERICSTRING:
911 case V_ASN1_PRINTABLESTRING:
912 case V_ASN1_T61STRING:
913 case V_ASN1_VIDEOTEXSTRING:
914 case V_ASN1_IA5STRING:
915 case V_ASN1_UTCTIME:
916 case V_ASN1_GENERALIZEDTIME:
917 case V_ASN1_GRAPHICSTRING:
918 case V_ASN1_VISIBLESTRING:
919 case V_ASN1_GENERALSTRING:
920 case V_ASN1_UNIVERSALSTRING:
921 case V_ASN1_BMPSTRING:
922 case V_ASN1_UTF8STRING:
923 case V_ASN1_OTHER:
924 case V_ASN1_SET:
925 case V_ASN1_SEQUENCE:
926 default:
927 if (utype == V_ASN1_BMPSTRING && (len & 1)) {
928 OPENSSL_PUT_ERROR(ASN1, ASN1_R_BMPSTRING_IS_WRONG_LENGTH);
929 goto err;
930 }
931 if (utype == V_ASN1_UNIVERSALSTRING && (len & 3)) {
932 OPENSSL_PUT_ERROR(ASN1, ASN1_R_UNIVERSALSTRING_IS_WRONG_LENGTH);
933 goto err;
934 }
935 /* All based on ASN1_STRING and handled the same */
936 if (!*pval) {
937 stmp = ASN1_STRING_type_new(utype);
938 if (!stmp) {
939 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
940 goto err;
941 }
942 *pval = (ASN1_VALUE *)stmp;
943 } else {
944 stmp = (ASN1_STRING *)*pval;
945 stmp->type = utype;
946 }
947 /* If we've already allocated a buffer use it */
948 if (*free_cont) {
949 if (stmp->data)
950 OPENSSL_free(stmp->data);
951 stmp->data = (unsigned char *)cont; /* UGLY CAST! RL */
952 stmp->length = len;
953 *free_cont = 0;
954 } else {
955 if (!ASN1_STRING_set(stmp, cont, len)) {
956 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
957 ASN1_STRING_free(stmp);
958 *pval = NULL;
959 goto err;
960 }
961 }
962 break;
963 }
964 /* If ASN1_ANY and NULL type fix up value */
965 if (typ && (utype == V_ASN1_NULL))
966 typ->value.ptr = NULL;
967
968 ret = 1;
969 err:
970 if (!ret) {
971 ASN1_TYPE_free(typ);
972 if (opval)
973 *opval = NULL;
974 }
975 return ret;
976 }
977
978 /*
979 * This function finds the end of an ASN1 structure when passed its maximum
980 * length, whether it is indefinite length and a pointer to the content. This
981 * is more efficient than calling asn1_collect because it does not recurse on
982 * each indefinite length header.
983 */
984
asn1_find_end(const unsigned char ** in,long len,char inf)985 static int asn1_find_end(const unsigned char **in, long len, char inf)
986 {
987 int expected_eoc;
988 long plen;
989 const unsigned char *p = *in, *q;
990 /* If not indefinite length constructed just add length */
991 if (inf == 0) {
992 *in += len;
993 return 1;
994 }
995 expected_eoc = 1;
996 /*
997 * Indefinite length constructed form. Find the end when enough EOCs are
998 * found. If more indefinite length constructed headers are encountered
999 * increment the expected eoc count otherwise just skip to the end of the
1000 * data.
1001 */
1002 while (len > 0) {
1003 if (asn1_check_eoc(&p, len)) {
1004 expected_eoc--;
1005 if (expected_eoc == 0)
1006 break;
1007 len -= 2;
1008 continue;
1009 }
1010 q = p;
1011 /* Just read in a header: only care about the length */
1012 if (!asn1_check_tlen(&plen, NULL, NULL, &inf, NULL, &p, len,
1013 -1, 0, 0, NULL)) {
1014 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
1015 return 0;
1016 }
1017 if (inf)
1018 expected_eoc++;
1019 else
1020 p += plen;
1021 len -= p - q;
1022 }
1023 if (expected_eoc) {
1024 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MISSING_EOC);
1025 return 0;
1026 }
1027 *in = p;
1028 return 1;
1029 }
1030
1031 /*
1032 * This function collects the asn1 data from a constructred string type into
1033 * a buffer. The values of 'in' and 'len' should refer to the contents of the
1034 * constructed type and 'inf' should be set if it is indefinite length.
1035 */
1036
1037 #ifndef ASN1_MAX_STRING_NEST
1038 /*
1039 * This determines how many levels of recursion are permitted in ASN1 string
1040 * types. If it is not limited stack overflows can occur. If set to zero no
1041 * recursion is allowed at all. Although zero should be adequate examples
1042 * exist that require a value of 1. So 5 should be more than enough.
1043 */
1044 # define ASN1_MAX_STRING_NEST 5
1045 #endif
1046
asn1_collect(BUF_MEM * buf,const unsigned char ** in,long len,char inf,int tag,int aclass,int depth)1047 static int asn1_collect(BUF_MEM *buf, const unsigned char **in, long len,
1048 char inf, int tag, int aclass, int depth)
1049 {
1050 const unsigned char *p, *q;
1051 long plen;
1052 char cst, ininf;
1053 p = *in;
1054 inf &= 1;
1055 /*
1056 * If no buffer and not indefinite length constructed just pass over the
1057 * encoded data
1058 */
1059 if (!buf && !inf) {
1060 *in += len;
1061 return 1;
1062 }
1063 while (len > 0) {
1064 q = p;
1065 /* Check for EOC */
1066 if (asn1_check_eoc(&p, len)) {
1067 /*
1068 * EOC is illegal outside indefinite length constructed form
1069 */
1070 if (!inf) {
1071 OPENSSL_PUT_ERROR(ASN1, ASN1_R_UNEXPECTED_EOC);
1072 return 0;
1073 }
1074 inf = 0;
1075 break;
1076 }
1077
1078 if (!asn1_check_tlen(&plen, NULL, NULL, &ininf, &cst, &p,
1079 len, tag, aclass, 0, NULL)) {
1080 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_ERROR);
1081 return 0;
1082 }
1083
1084 /* If indefinite length constructed update max length */
1085 if (cst) {
1086 if (depth >= ASN1_MAX_STRING_NEST) {
1087 OPENSSL_PUT_ERROR(ASN1, ASN1_R_NESTED_ASN1_STRING);
1088 return 0;
1089 }
1090 if (!asn1_collect(buf, &p, plen, ininf, tag, aclass, depth + 1))
1091 return 0;
1092 } else if (plen && !collect_data(buf, &p, plen))
1093 return 0;
1094 len -= p - q;
1095 }
1096 if (inf) {
1097 OPENSSL_PUT_ERROR(ASN1, ASN1_R_MISSING_EOC);
1098 return 0;
1099 }
1100 *in = p;
1101 return 1;
1102 }
1103
collect_data(BUF_MEM * buf,const unsigned char ** p,long plen)1104 static int collect_data(BUF_MEM *buf, const unsigned char **p, long plen)
1105 {
1106 int len;
1107 if (buf) {
1108 len = buf->length;
1109 if (!BUF_MEM_grow_clean(buf, len + plen)) {
1110 OPENSSL_PUT_ERROR(ASN1, ERR_R_MALLOC_FAILURE);
1111 return 0;
1112 }
1113 OPENSSL_memcpy(buf->data + len, *p, plen);
1114 }
1115 *p += plen;
1116 return 1;
1117 }
1118
1119 /* Check for ASN1 EOC and swallow it if found */
1120
asn1_check_eoc(const unsigned char ** in,long len)1121 static int asn1_check_eoc(const unsigned char **in, long len)
1122 {
1123 const unsigned char *p;
1124 if (len < 2)
1125 return 0;
1126 p = *in;
1127 if (!p[0] && !p[1]) {
1128 *in += 2;
1129 return 1;
1130 }
1131 return 0;
1132 }
1133
1134 /*
1135 * Check an ASN1 tag and length: a bit like ASN1_get_object but it sets the
1136 * length for indefinite length constructed form, we don't know the exact
1137 * length but we can set an upper bound to the amount of data available minus
1138 * the header length just read.
1139 */
1140
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)1141 static int asn1_check_tlen(long *olen, int *otag, unsigned char *oclass,
1142 char *inf, char *cst,
1143 const unsigned char **in, long len,
1144 int exptag, int expclass, char opt, ASN1_TLC *ctx)
1145 {
1146 int i;
1147 int ptag, pclass;
1148 long plen;
1149 const unsigned char *p, *q;
1150 p = *in;
1151 q = p;
1152
1153 if (ctx && ctx->valid) {
1154 i = ctx->ret;
1155 plen = ctx->plen;
1156 pclass = ctx->pclass;
1157 ptag = ctx->ptag;
1158 p += ctx->hdrlen;
1159 } else {
1160 i = ASN1_get_object(&p, &plen, &ptag, &pclass, len);
1161 if (ctx) {
1162 ctx->ret = i;
1163 ctx->plen = plen;
1164 ctx->pclass = pclass;
1165 ctx->ptag = ptag;
1166 ctx->hdrlen = p - q;
1167 ctx->valid = 1;
1168 /*
1169 * If definite length, and no error, length + header can't exceed
1170 * total amount of data available.
1171 */
1172 if (!(i & 0x81) && ((plen + ctx->hdrlen) > len)) {
1173 OPENSSL_PUT_ERROR(ASN1, ASN1_R_TOO_LONG);
1174 asn1_tlc_clear(ctx);
1175 return 0;
1176 }
1177 }
1178 }
1179
1180 if (i & 0x80) {
1181 OPENSSL_PUT_ERROR(ASN1, ASN1_R_BAD_OBJECT_HEADER);
1182 asn1_tlc_clear(ctx);
1183 return 0;
1184 }
1185 if (exptag >= 0) {
1186 if ((exptag != ptag) || (expclass != pclass)) {
1187 /*
1188 * If type is OPTIONAL, not an error: indicate missing type.
1189 */
1190 if (opt)
1191 return -1;
1192 asn1_tlc_clear(ctx);
1193 OPENSSL_PUT_ERROR(ASN1, ASN1_R_WRONG_TAG);
1194 return 0;
1195 }
1196 /*
1197 * We have a tag and class match: assume we are going to do something
1198 * with it
1199 */
1200 asn1_tlc_clear(ctx);
1201 }
1202
1203 if (i & 1)
1204 plen = len - (p - q);
1205
1206 if (inf)
1207 *inf = i & 1;
1208
1209 if (cst)
1210 *cst = i & V_ASN1_CONSTRUCTED;
1211
1212 if (olen)
1213 *olen = plen;
1214
1215 if (oclass)
1216 *oclass = pclass;
1217
1218 if (otag)
1219 *otag = ptag;
1220
1221 *in = p;
1222 return 1;
1223 }
1224