dbwrap: Use tdb_null in db_ctdb_delete
[Samba/gbeck.git] / lib / util / asn1.c
blob70637a3e065c48d5063a95d22bea392559f35622
1 /*
2 Unix SMB/CIFS implementation.
3 simple ASN1 routines
4 Copyright (C) Andrew Tridgell 2001
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include "includes.h"
21 #include "../lib/util/asn1.h"
23 /* allocate an asn1 structure */
24 struct asn1_data *asn1_init(TALLOC_CTX *mem_ctx)
26 struct asn1_data *ret = talloc_zero(mem_ctx, struct asn1_data);
27 if (ret == NULL) {
28 DEBUG(0,("asn1_init failed! out of memory\n"));
30 return ret;
33 /* free an asn1 structure */
34 void asn1_free(struct asn1_data *data)
36 talloc_free(data);
39 /* write to the ASN1 buffer, advancing the buffer pointer */
40 bool asn1_write(struct asn1_data *data, const void *p, int len)
42 if (data->has_error) return false;
43 if (data->length < data->ofs+len) {
44 uint8_t *newp;
45 newp = talloc_realloc(data, data->data, uint8_t, data->ofs+len);
46 if (!newp) {
47 asn1_free(data);
48 data->has_error = true;
49 return false;
51 data->data = newp;
52 data->length = data->ofs+len;
54 memcpy(data->data + data->ofs, p, len);
55 data->ofs += len;
56 return true;
59 /* useful fn for writing a uint8_t */
60 bool asn1_write_uint8(struct asn1_data *data, uint8_t v)
62 return asn1_write(data, &v, 1);
65 /* push a tag onto the asn1 data buffer. Used for nested structures */
66 bool asn1_push_tag(struct asn1_data *data, uint8_t tag)
68 struct nesting *nesting;
70 asn1_write_uint8(data, tag);
71 nesting = talloc(data, struct nesting);
72 if (!nesting) {
73 data->has_error = true;
74 return false;
77 nesting->start = data->ofs;
78 nesting->next = data->nesting;
79 data->nesting = nesting;
80 return asn1_write_uint8(data, 0xff);
83 /* pop a tag */
84 bool asn1_pop_tag(struct asn1_data *data)
86 struct nesting *nesting;
87 size_t len;
89 nesting = data->nesting;
91 if (!nesting) {
92 data->has_error = true;
93 return false;
95 len = data->ofs - (nesting->start+1);
96 /* yes, this is ugly. We don't know in advance how many bytes the length
97 of a tag will take, so we assumed 1 byte. If we were wrong then we
98 need to correct our mistake */
99 if (len > 0xFFFFFF) {
100 data->data[nesting->start] = 0x84;
101 if (!asn1_write_uint8(data, 0)) return false;
102 if (!asn1_write_uint8(data, 0)) return false;
103 if (!asn1_write_uint8(data, 0)) return false;
104 if (!asn1_write_uint8(data, 0)) return false;
105 memmove(data->data+nesting->start+5, data->data+nesting->start+1, len);
106 data->data[nesting->start+1] = (len>>24) & 0xFF;
107 data->data[nesting->start+2] = (len>>16) & 0xFF;
108 data->data[nesting->start+3] = (len>>8) & 0xFF;
109 data->data[nesting->start+4] = len&0xff;
110 } else if (len > 0xFFFF) {
111 data->data[nesting->start] = 0x83;
112 if (!asn1_write_uint8(data, 0)) return false;
113 if (!asn1_write_uint8(data, 0)) return false;
114 if (!asn1_write_uint8(data, 0)) return false;
115 memmove(data->data+nesting->start+4, data->data+nesting->start+1, len);
116 data->data[nesting->start+1] = (len>>16) & 0xFF;
117 data->data[nesting->start+2] = (len>>8) & 0xFF;
118 data->data[nesting->start+3] = len&0xff;
119 } else if (len > 255) {
120 data->data[nesting->start] = 0x82;
121 if (!asn1_write_uint8(data, 0)) return false;
122 if (!asn1_write_uint8(data, 0)) return false;
123 memmove(data->data+nesting->start+3, data->data+nesting->start+1, len);
124 data->data[nesting->start+1] = len>>8;
125 data->data[nesting->start+2] = len&0xff;
126 } else if (len > 127) {
127 data->data[nesting->start] = 0x81;
128 if (!asn1_write_uint8(data, 0)) return false;
129 memmove(data->data+nesting->start+2, data->data+nesting->start+1, len);
130 data->data[nesting->start+1] = len;
131 } else {
132 data->data[nesting->start] = len;
135 data->nesting = nesting->next;
136 talloc_free(nesting);
137 return true;
140 /* "i" is the one's complement representation, as is the normal result of an
141 * implicit signed->unsigned conversion */
143 static bool push_int_bigendian(struct asn1_data *data, unsigned int i, bool negative)
145 uint8_t lowest = i & 0xFF;
147 i = i >> 8;
148 if (i != 0)
149 if (!push_int_bigendian(data, i, negative))
150 return false;
152 if (data->nesting->start+1 == data->ofs) {
154 /* We did not write anything yet, looking at the highest
155 * valued byte */
157 if (negative) {
158 /* Don't write leading 0xff's */
159 if (lowest == 0xFF)
160 return true;
162 if ((lowest & 0x80) == 0) {
163 /* The only exception for a leading 0xff is if
164 * the highest bit is 0, which would indicate
165 * a positive value */
166 if (!asn1_write_uint8(data, 0xff))
167 return false;
169 } else {
170 if (lowest & 0x80) {
171 /* The highest bit of a positive integer is 1,
172 * this would indicate a negative number. Push
173 * a 0 to indicate a positive one */
174 if (!asn1_write_uint8(data, 0))
175 return false;
180 return asn1_write_uint8(data, lowest);
183 /* write an Integer without the tag framing. Needed for example for the LDAP
184 * Abandon Operation */
186 bool asn1_write_implicit_Integer(struct asn1_data *data, int i)
188 if (i == -1) {
189 /* -1 is special as it consists of all-0xff bytes. In
190 push_int_bigendian this is the only case that is not
191 properly handled, as all 0xff bytes would be handled as
192 leading ones to be ignored. */
193 return asn1_write_uint8(data, 0xff);
194 } else {
195 return push_int_bigendian(data, i, i<0);
200 /* write an integer */
201 bool asn1_write_Integer(struct asn1_data *data, int i)
203 if (!asn1_push_tag(data, ASN1_INTEGER)) return false;
204 if (!asn1_write_implicit_Integer(data, i)) return false;
205 return asn1_pop_tag(data);
208 /* write a BIT STRING */
209 bool asn1_write_BitString(struct asn1_data *data, const void *p, size_t length, uint8_t padding)
211 if (!asn1_push_tag(data, ASN1_BIT_STRING)) return false;
212 if (!asn1_write_uint8(data, padding)) return false;
213 if (!asn1_write(data, p, length)) return false;
214 return asn1_pop_tag(data);
217 bool ber_write_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, const char *OID)
219 unsigned int v, v2;
220 const char *p = (const char *)OID;
221 char *newp;
222 int i;
224 if (!isdigit(*p)) return false;
225 v = strtoul(p, &newp, 10);
226 if (newp[0] != '.') return false;
227 p = newp + 1;
229 if (!isdigit(*p)) return false;
230 v2 = strtoul(p, &newp, 10);
231 if (newp[0] != '.') return false;
232 p = newp + 1;
234 /*the ber representation can't use more space then the string one */
235 *blob = data_blob_talloc(mem_ctx, NULL, strlen(OID));
236 if (!blob->data) return false;
238 blob->data[0] = 40*v + v2;
240 i = 1;
241 while (*p) {
242 if (!isdigit(*p)) return false;
243 v = strtoul(p, &newp, 10);
244 if (newp[0] == '.') {
245 p = newp + 1;
246 /* check for empty last component */
247 if (!*p) return false;
248 } else if (newp[0] == '\0') {
249 p = newp;
250 } else {
251 data_blob_free(blob);
252 return false;
254 if (v >= (1<<28)) blob->data[i++] = (0x80 | ((v>>28)&0x7f));
255 if (v >= (1<<21)) blob->data[i++] = (0x80 | ((v>>21)&0x7f));
256 if (v >= (1<<14)) blob->data[i++] = (0x80 | ((v>>14)&0x7f));
257 if (v >= (1<<7)) blob->data[i++] = (0x80 | ((v>>7)&0x7f));
258 blob->data[i++] = (v&0x7f);
261 blob->length = i;
263 return true;
267 * Serialize partial OID string.
268 * Partial OIDs are in the form:
269 * 1:2.5.6:0x81
270 * 1:2.5.6:0x8182
272 bool ber_write_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, const char *partial_oid)
274 TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
275 char *oid = talloc_strdup(tmp_ctx, partial_oid);
276 char *p;
278 /* truncate partial part so ber_write_OID_String() works */
279 p = strchr(oid, ':');
280 if (p) {
281 *p = '\0';
282 p++;
285 if (!ber_write_OID_String(mem_ctx, blob, oid)) {
286 talloc_free(tmp_ctx);
287 return false;
290 /* Add partially encoded sub-identifier */
291 if (p) {
292 DATA_BLOB tmp_blob = strhex_to_data_blob(tmp_ctx, p);
293 if (!data_blob_append(mem_ctx, blob, tmp_blob.data,
294 tmp_blob.length)) {
295 talloc_free(tmp_ctx);
296 return false;
300 talloc_free(tmp_ctx);
302 return true;
305 /* write an object ID to a ASN1 buffer */
306 bool asn1_write_OID(struct asn1_data *data, const char *OID)
308 DATA_BLOB blob;
310 if (!asn1_push_tag(data, ASN1_OID)) return false;
312 if (!ber_write_OID_String(NULL, &blob, OID)) {
313 data->has_error = true;
314 return false;
317 if (!asn1_write(data, blob.data, blob.length)) {
318 data_blob_free(&blob);
319 data->has_error = true;
320 return false;
322 data_blob_free(&blob);
323 return asn1_pop_tag(data);
326 /* write an octet string */
327 bool asn1_write_OctetString(struct asn1_data *data, const void *p, size_t length)
329 asn1_push_tag(data, ASN1_OCTET_STRING);
330 asn1_write(data, p, length);
331 asn1_pop_tag(data);
332 return !data->has_error;
335 /* write a LDAP string */
336 bool asn1_write_LDAPString(struct asn1_data *data, const char *s)
338 asn1_write(data, s, strlen(s));
339 return !data->has_error;
342 /* write a LDAP string from a DATA_BLOB */
343 bool asn1_write_DATA_BLOB_LDAPString(struct asn1_data *data, const DATA_BLOB *s)
345 asn1_write(data, s->data, s->length);
346 return !data->has_error;
349 /* write a general string */
350 bool asn1_write_GeneralString(struct asn1_data *data, const char *s)
352 asn1_push_tag(data, ASN1_GENERAL_STRING);
353 asn1_write_LDAPString(data, s);
354 asn1_pop_tag(data);
355 return !data->has_error;
358 bool asn1_write_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
360 asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(num));
361 asn1_write(data, blob->data, blob->length);
362 asn1_pop_tag(data);
363 return !data->has_error;
366 /* write a BOOLEAN */
367 bool asn1_write_BOOLEAN(struct asn1_data *data, bool v)
369 asn1_push_tag(data, ASN1_BOOLEAN);
370 asn1_write_uint8(data, v ? 0xFF : 0);
371 asn1_pop_tag(data);
372 return !data->has_error;
375 bool asn1_read_BOOLEAN(struct asn1_data *data, bool *v)
377 uint8_t tmp = 0;
378 asn1_start_tag(data, ASN1_BOOLEAN);
379 asn1_read_uint8(data, &tmp);
380 if (tmp == 0xFF) {
381 *v = true;
382 } else {
383 *v = false;
385 asn1_end_tag(data);
386 return !data->has_error;
389 /* write a BOOLEAN in a simple context */
390 bool asn1_write_BOOLEAN_context(struct asn1_data *data, bool v, int context)
392 asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(context));
393 asn1_write_uint8(data, v ? 0xFF : 0);
394 asn1_pop_tag(data);
395 return !data->has_error;
398 bool asn1_read_BOOLEAN_context(struct asn1_data *data, bool *v, int context)
400 uint8_t tmp = 0;
401 asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(context));
402 asn1_read_uint8(data, &tmp);
403 if (tmp == 0xFF) {
404 *v = true;
405 } else {
406 *v = false;
408 asn1_end_tag(data);
409 return !data->has_error;
412 /* check a BOOLEAN */
413 bool asn1_check_BOOLEAN(struct asn1_data *data, bool v)
415 uint8_t b = 0;
417 asn1_read_uint8(data, &b);
418 if (b != ASN1_BOOLEAN) {
419 data->has_error = true;
420 return false;
422 asn1_read_uint8(data, &b);
423 if (b != v) {
424 data->has_error = true;
425 return false;
427 return !data->has_error;
431 /* load a struct asn1_data structure with a lump of data, ready to be parsed */
432 bool asn1_load(struct asn1_data *data, DATA_BLOB blob)
434 ZERO_STRUCTP(data);
435 data->data = (uint8_t *)talloc_memdup(data, blob.data, blob.length);
436 if (!data->data) {
437 data->has_error = true;
438 return false;
440 data->length = blob.length;
441 return true;
444 /* Peek into an ASN1 buffer, not advancing the pointer */
445 bool asn1_peek(struct asn1_data *data, void *p, int len)
447 if (data->has_error)
448 return false;
450 if (len < 0 || data->ofs + len < data->ofs || data->ofs + len < len)
451 return false;
453 if (data->ofs + len > data->length) {
454 /* we need to mark the buffer as consumed, so the caller knows
455 this was an out of data error, and not a decode error */
456 data->ofs = data->length;
457 return false;
460 memcpy(p, data->data + data->ofs, len);
461 return true;
464 /* read from a ASN1 buffer, advancing the buffer pointer */
465 bool asn1_read(struct asn1_data *data, void *p, int len)
467 if (!asn1_peek(data, p, len)) {
468 data->has_error = true;
469 return false;
472 data->ofs += len;
473 return true;
476 /* read a uint8_t from a ASN1 buffer */
477 bool asn1_read_uint8(struct asn1_data *data, uint8_t *v)
479 return asn1_read(data, v, 1);
482 bool asn1_peek_uint8(struct asn1_data *data, uint8_t *v)
484 return asn1_peek(data, v, 1);
487 bool asn1_peek_tag(struct asn1_data *data, uint8_t tag)
489 uint8_t b;
491 if (asn1_tag_remaining(data) <= 0) {
492 return false;
495 if (!asn1_peek_uint8(data, &b))
496 return false;
498 return (b == tag);
502 * just get the needed size the tag would consume
504 bool asn1_peek_tag_needed_size(struct asn1_data *data, uint8_t tag, size_t *size)
506 off_t start_ofs = data->ofs;
507 uint8_t b;
508 size_t taglen = 0;
510 if (data->has_error) {
511 return false;
514 if (!asn1_read_uint8(data, &b)) {
515 data->ofs = start_ofs;
516 data->has_error = false;
517 return false;
520 if (b != tag) {
521 data->ofs = start_ofs;
522 data->has_error = false;
523 return false;
526 if (!asn1_read_uint8(data, &b)) {
527 data->ofs = start_ofs;
528 data->has_error = false;
529 return false;
532 if (b & 0x80) {
533 int n = b & 0x7f;
534 if (!asn1_read_uint8(data, &b)) {
535 data->ofs = start_ofs;
536 data->has_error = false;
537 return false;
539 if (n > 4) {
541 * We should not allow more than 4 bytes
542 * for the encoding of the tag length.
544 * Otherwise we'd overflow the taglen
545 * variable on 32 bit systems.
547 data->ofs = start_ofs;
548 data->has_error = false;
549 return false;
551 taglen = b;
552 while (n > 1) {
553 if (!asn1_read_uint8(data, &b)) {
554 data->ofs = start_ofs;
555 data->has_error = false;
556 return false;
558 taglen = (taglen << 8) | b;
559 n--;
561 } else {
562 taglen = b;
565 *size = (data->ofs - start_ofs) + taglen;
567 data->ofs = start_ofs;
568 data->has_error = false;
569 return true;
572 /* start reading a nested asn1 structure */
573 bool asn1_start_tag(struct asn1_data *data, uint8_t tag)
575 uint8_t b;
576 struct nesting *nesting;
578 if (!asn1_read_uint8(data, &b))
579 return false;
581 if (b != tag) {
582 data->has_error = true;
583 return false;
585 nesting = talloc(data, struct nesting);
586 if (!nesting) {
587 data->has_error = true;
588 return false;
591 if (!asn1_read_uint8(data, &b)) {
592 return false;
595 if (b & 0x80) {
596 int n = b & 0x7f;
597 if (!asn1_read_uint8(data, &b))
598 return false;
599 nesting->taglen = b;
600 while (n > 1) {
601 if (!asn1_read_uint8(data, &b))
602 return false;
603 nesting->taglen = (nesting->taglen << 8) | b;
604 n--;
606 } else {
607 nesting->taglen = b;
609 nesting->start = data->ofs;
610 nesting->next = data->nesting;
611 data->nesting = nesting;
612 if (asn1_tag_remaining(data) == -1) {
613 return false;
615 return !data->has_error;
618 /* stop reading a tag */
619 bool asn1_end_tag(struct asn1_data *data)
621 struct nesting *nesting;
623 /* make sure we read it all */
624 if (asn1_tag_remaining(data) != 0) {
625 data->has_error = true;
626 return false;
629 nesting = data->nesting;
631 if (!nesting) {
632 data->has_error = true;
633 return false;
636 data->nesting = nesting->next;
637 talloc_free(nesting);
638 return true;
641 /* work out how many bytes are left in this nested tag */
642 int asn1_tag_remaining(struct asn1_data *data)
644 int remaining;
645 if (data->has_error) {
646 return -1;
649 if (!data->nesting) {
650 data->has_error = true;
651 return -1;
653 remaining = data->nesting->taglen - (data->ofs - data->nesting->start);
654 if (remaining > (data->length - data->ofs)) {
655 data->has_error = true;
656 return -1;
658 return remaining;
662 * Internal implementation for reading binary OIDs
663 * Reading is done as far in the buffer as valid OID
664 * till buffer ends or not valid sub-identifier is found.
666 static bool _ber_read_OID_String_impl(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
667 char **OID, size_t *bytes_eaten)
669 int i;
670 uint8_t *b;
671 unsigned int v;
672 char *tmp_oid = NULL;
674 if (blob.length < 2) return false;
676 b = blob.data;
678 tmp_oid = talloc_asprintf(mem_ctx, "%u", b[0]/40);
679 if (!tmp_oid) goto nomem;
680 tmp_oid = talloc_asprintf_append_buffer(tmp_oid, ".%u", b[0]%40);
681 if (!tmp_oid) goto nomem;
683 if (bytes_eaten != NULL) {
684 *bytes_eaten = 0;
687 for(i = 1, v = 0; i < blob.length; i++) {
688 v = (v<<7) | (b[i]&0x7f);
689 if ( ! (b[i] & 0x80)) {
690 tmp_oid = talloc_asprintf_append_buffer(tmp_oid, ".%u", v);
691 v = 0;
692 if (bytes_eaten)
693 *bytes_eaten = i+1;
695 if (!tmp_oid) goto nomem;
698 *OID = tmp_oid;
699 return true;
701 nomem:
702 return false;
705 /* read an object ID from a data blob */
706 bool ber_read_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob, char **OID)
708 size_t bytes_eaten;
710 if (!_ber_read_OID_String_impl(mem_ctx, blob, OID, &bytes_eaten))
711 return false;
713 return (bytes_eaten == blob.length);
717 * Deserialize partial OID string.
718 * Partial OIDs are in the form:
719 * 1:2.5.6:0x81
720 * 1:2.5.6:0x8182
722 bool ber_read_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
723 char **partial_oid)
725 size_t bytes_left;
726 size_t bytes_eaten;
727 char *identifier = NULL;
728 char *tmp_oid = NULL;
730 if (!_ber_read_OID_String_impl(mem_ctx, blob, &tmp_oid, &bytes_eaten))
731 return false;
733 if (bytes_eaten < blob.length) {
734 bytes_left = blob.length - bytes_eaten;
735 identifier = hex_encode_talloc(mem_ctx, &blob.data[bytes_eaten], bytes_left);
736 if (!identifier) goto nomem;
738 *partial_oid = talloc_asprintf_append_buffer(tmp_oid, ":0x%s", identifier);
739 if (!*partial_oid) goto nomem;
740 TALLOC_FREE(identifier);
741 } else {
742 *partial_oid = tmp_oid;
745 return true;
747 nomem:
748 TALLOC_FREE(identifier);
749 TALLOC_FREE(tmp_oid);
750 return false;
753 /* read an object ID from a ASN1 buffer */
754 bool asn1_read_OID(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **OID)
756 DATA_BLOB blob;
757 int len;
759 if (!asn1_start_tag(data, ASN1_OID)) return false;
761 len = asn1_tag_remaining(data);
762 if (len < 0) {
763 data->has_error = true;
764 return false;
767 blob = data_blob(NULL, len);
768 if (!blob.data) {
769 data->has_error = true;
770 return false;
773 asn1_read(data, blob.data, len);
774 asn1_end_tag(data);
775 if (data->has_error) {
776 data_blob_free(&blob);
777 return false;
780 if (!ber_read_OID_String(mem_ctx, blob, OID)) {
781 data->has_error = true;
782 data_blob_free(&blob);
783 return false;
786 data_blob_free(&blob);
787 return true;
790 /* check that the next object ID is correct */
791 bool asn1_check_OID(struct asn1_data *data, const char *OID)
793 char *id;
795 if (!asn1_read_OID(data, data, &id)) return false;
797 if (strcmp(id, OID) != 0) {
798 talloc_free(id);
799 data->has_error = true;
800 return false;
802 talloc_free(id);
803 return true;
806 /* read a LDAPString from a ASN1 buffer */
807 bool asn1_read_LDAPString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
809 int len;
810 len = asn1_tag_remaining(data);
811 if (len < 0) {
812 data->has_error = true;
813 return false;
815 *s = talloc_array(mem_ctx, char, len+1);
816 if (! *s) {
817 data->has_error = true;
818 return false;
820 asn1_read(data, *s, len);
821 (*s)[len] = 0;
822 return !data->has_error;
826 /* read a GeneralString from a ASN1 buffer */
827 bool asn1_read_GeneralString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
829 if (!asn1_start_tag(data, ASN1_GENERAL_STRING)) return false;
830 if (!asn1_read_LDAPString(data, mem_ctx, s)) return false;
831 return asn1_end_tag(data);
835 /* read a octet string blob */
836 bool asn1_read_OctetString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
838 int len;
839 ZERO_STRUCTP(blob);
840 if (!asn1_start_tag(data, ASN1_OCTET_STRING)) return false;
841 len = asn1_tag_remaining(data);
842 if (len < 0) {
843 data->has_error = true;
844 return false;
846 *blob = data_blob_talloc(mem_ctx, NULL, len+1);
847 if (!blob->data || blob->length < len) {
848 data->has_error = true;
849 return false;
851 asn1_read(data, blob->data, len);
852 asn1_end_tag(data);
853 blob->length--;
854 blob->data[len] = 0;
856 if (data->has_error) {
857 data_blob_free(blob);
858 *blob = data_blob_null;
859 return false;
861 return true;
864 bool asn1_read_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
866 int len;
867 ZERO_STRUCTP(blob);
868 if (!asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(num))) return false;
869 len = asn1_tag_remaining(data);
870 if (len < 0) {
871 data->has_error = true;
872 return false;
874 *blob = data_blob(NULL, len);
875 if ((len != 0) && (!blob->data)) {
876 data->has_error = true;
877 return false;
879 asn1_read(data, blob->data, len);
880 asn1_end_tag(data);
881 return !data->has_error;
884 /* read an integer without tag*/
885 bool asn1_read_implicit_Integer(struct asn1_data *data, int *i)
887 uint8_t b;
888 bool first_byte = true;
889 *i = 0;
891 while (!data->has_error && asn1_tag_remaining(data)>0) {
892 if (!asn1_read_uint8(data, &b)) return false;
893 if (first_byte) {
894 if (b & 0x80) {
895 /* Number is negative.
896 Set i to -1 for sign extend. */
897 *i = -1;
899 first_byte = false;
901 *i = (*i << 8) + b;
903 return !data->has_error;
907 /* read an integer */
908 bool asn1_read_Integer(struct asn1_data *data, int *i)
910 *i = 0;
912 if (!asn1_start_tag(data, ASN1_INTEGER)) return false;
913 if (!asn1_read_implicit_Integer(data, i)) return false;
914 return asn1_end_tag(data);
917 /* read a BIT STRING */
918 bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding)
920 int len;
921 ZERO_STRUCTP(blob);
922 if (!asn1_start_tag(data, ASN1_BIT_STRING)) return false;
923 len = asn1_tag_remaining(data);
924 if (len < 0) {
925 data->has_error = true;
926 return false;
928 if (!asn1_read_uint8(data, padding)) return false;
930 *blob = data_blob_talloc(mem_ctx, NULL, len+1);
931 if (!blob->data || blob->length < len) {
932 data->has_error = true;
933 return false;
935 if (asn1_read(data, blob->data, len - 1)) {
936 blob->length--;
937 blob->data[len] = 0;
938 asn1_end_tag(data);
941 if (data->has_error) {
942 data_blob_free(blob);
943 *blob = data_blob_null;
944 *padding = 0;
945 return false;
947 return true;
950 /* read an integer */
951 bool asn1_read_enumerated(struct asn1_data *data, int *v)
953 *v = 0;
955 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
956 while (!data->has_error && asn1_tag_remaining(data)>0) {
957 uint8_t b;
958 asn1_read_uint8(data, &b);
959 *v = (*v << 8) + b;
961 return asn1_end_tag(data);
964 /* check a enumerated value is correct */
965 bool asn1_check_enumerated(struct asn1_data *data, int v)
967 uint8_t b;
968 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
969 asn1_read_uint8(data, &b);
970 asn1_end_tag(data);
972 if (v != b)
973 data->has_error = false;
975 return !data->has_error;
978 /* write an enumerated value to the stream */
979 bool asn1_write_enumerated(struct asn1_data *data, uint8_t v)
981 if (!asn1_push_tag(data, ASN1_ENUMERATED)) return false;
982 asn1_write_uint8(data, v);
983 asn1_pop_tag(data);
984 return !data->has_error;
988 Get us the data just written without copying
990 bool asn1_blob(const struct asn1_data *asn1, DATA_BLOB *blob)
992 if (asn1->has_error) {
993 return false;
995 if (asn1->nesting != NULL) {
996 return false;
998 blob->data = asn1->data;
999 blob->length = asn1->length;
1000 return true;
1004 Fill in an asn1 struct without making a copy
1006 void asn1_load_nocopy(struct asn1_data *data, uint8_t *buf, size_t len)
1008 ZERO_STRUCTP(data);
1009 data->data = buf;
1010 data->length = len;
1014 check if a ASN.1 blob is a full tag
1016 NTSTATUS asn1_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
1018 struct asn1_data *asn1 = asn1_init(NULL);
1019 int size;
1021 NT_STATUS_HAVE_NO_MEMORY(asn1);
1023 asn1->data = blob.data;
1024 asn1->length = blob.length;
1025 asn1_start_tag(asn1, tag);
1026 if (asn1->has_error) {
1027 talloc_free(asn1);
1028 return STATUS_MORE_ENTRIES;
1030 size = asn1_tag_remaining(asn1) + asn1->ofs;
1032 talloc_free(asn1);
1034 if (size > blob.length) {
1035 return STATUS_MORE_ENTRIES;
1038 *packet_size = size;
1039 return NT_STATUS_OK;
1042 NTSTATUS asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
1044 struct asn1_data asn1;
1045 size_t size;
1046 bool ok;
1048 ZERO_STRUCT(asn1);
1049 asn1.data = blob.data;
1050 asn1.length = blob.length;
1052 ok = asn1_peek_tag_needed_size(&asn1, tag, &size);
1053 if (!ok) {
1054 return NT_STATUS_INVALID_BUFFER_SIZE;
1057 if (size > blob.length) {
1058 *packet_size = size;
1059 return STATUS_MORE_ENTRIES;
1062 *packet_size = size;
1063 return NT_STATUS_OK;