2 Unix SMB/CIFS implementation.
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/>.
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);
28 DEBUG(0,("asn1_init failed! out of memory\n"));
33 /* free an asn1 structure */
34 void asn1_free(struct asn1_data *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) {
45 newp = talloc_realloc(data, data->data, uint8_t, data->ofs+len);
48 data->has_error = true;
52 data->length = data->ofs+len;
54 memcpy(data->data + data->ofs, p, len);
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);
73 data->has_error = true;
77 nesting->start = data->ofs;
78 nesting->next = data->nesting;
79 data->nesting = nesting;
80 return asn1_write_uint8(data, 0xff);
84 bool asn1_pop_tag(struct asn1_data *data)
86 struct nesting *nesting;
89 nesting = data->nesting;
92 data->has_error = true;
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 */
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;
132 data->data[nesting->start] = len;
135 data->nesting = nesting->next;
136 talloc_free(nesting);
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;
149 if (!push_int_bigendian(data, i, negative))
152 if (data->nesting->start+1 == data->ofs) {
154 /* We did not write anything yet, looking at the highest
158 /* Don't write leading 0xff's */
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))
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))
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)
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);
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)
220 const char *p = (const char *)OID;
224 v = strtoul(p, &newp, 10);
225 if (newp[0] != '.') return false;
228 v2 = strtoul(p, &newp, 10);
229 if (newp[0] != '.') return false;
232 /*the ber representation can't use more space then the string one */
233 *blob = data_blob_talloc(mem_ctx, NULL, strlen(OID));
234 if (!blob->data) return false;
236 blob->data[0] = 40*v + v2;
240 v = strtoul(p, &newp, 10);
241 if (newp[0] == '.') {
243 } else if (newp[0] == '\0') {
246 data_blob_free(blob);
249 if (v >= (1<<28)) blob->data[i++] = (0x80 | ((v>>28)&0x7f));
250 if (v >= (1<<21)) blob->data[i++] = (0x80 | ((v>>21)&0x7f));
251 if (v >= (1<<14)) blob->data[i++] = (0x80 | ((v>>14)&0x7f));
252 if (v >= (1<<7)) blob->data[i++] = (0x80 | ((v>>7)&0x7f));
253 blob->data[i++] = (v&0x7f);
262 * Serialize partial OID string.
263 * Partial OIDs are in the form:
267 bool ber_write_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, const char *partial_oid)
269 TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
270 char *oid = talloc_strdup(tmp_ctx, partial_oid);
273 /* truncate partial part so ber_write_OID_String() works */
274 p = strchr(oid, ':');
280 if (!ber_write_OID_String(mem_ctx, blob, oid)) {
281 talloc_free(tmp_ctx);
285 /* Add partially endcoded subidentifier */
287 DATA_BLOB tmp_blob = strhex_to_data_blob(tmp_ctx, p);
288 data_blob_append(mem_ctx, blob, tmp_blob.data, tmp_blob.length);
291 talloc_free(tmp_ctx);
296 /* write an object ID to a ASN1 buffer */
297 bool asn1_write_OID(struct asn1_data *data, const char *OID)
301 if (!asn1_push_tag(data, ASN1_OID)) return false;
303 if (!ber_write_OID_String(NULL, &blob, OID)) {
304 data->has_error = true;
308 if (!asn1_write(data, blob.data, blob.length)) {
309 data_blob_free(&blob);
310 data->has_error = true;
313 data_blob_free(&blob);
314 return asn1_pop_tag(data);
317 /* write an octet string */
318 bool asn1_write_OctetString(struct asn1_data *data, const void *p, size_t length)
320 asn1_push_tag(data, ASN1_OCTET_STRING);
321 asn1_write(data, p, length);
323 return !data->has_error;
326 /* write a LDAP string */
327 bool asn1_write_LDAPString(struct asn1_data *data, const char *s)
329 asn1_write(data, s, strlen(s));
330 return !data->has_error;
333 /* write a LDAP string from a DATA_BLOB */
334 bool asn1_write_DATA_BLOB_LDAPString(struct asn1_data *data, const DATA_BLOB *s)
336 asn1_write(data, s->data, s->length);
337 return !data->has_error;
340 /* write a general string */
341 bool asn1_write_GeneralString(struct asn1_data *data, const char *s)
343 asn1_push_tag(data, ASN1_GENERAL_STRING);
344 asn1_write_LDAPString(data, s);
346 return !data->has_error;
349 bool asn1_write_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
351 asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(num));
352 asn1_write(data, blob->data, blob->length);
354 return !data->has_error;
357 /* write a BOOLEAN */
358 bool asn1_write_BOOLEAN(struct asn1_data *data, bool v)
360 asn1_push_tag(data, ASN1_BOOLEAN);
361 asn1_write_uint8(data, v ? 0xFF : 0);
363 return !data->has_error;
366 bool asn1_read_BOOLEAN(struct asn1_data *data, bool *v)
369 asn1_start_tag(data, ASN1_BOOLEAN);
370 asn1_read_uint8(data, &tmp);
377 return !data->has_error;
380 /* write a BOOLEAN in a simple context */
381 bool asn1_write_BOOLEAN_context(struct asn1_data *data, bool v, int context)
383 asn1_push_tag(data, ASN1_CONTEXT_SIMPLE(context));
384 asn1_write_uint8(data, v ? 0xFF : 0);
386 return !data->has_error;
389 bool asn1_read_BOOLEAN_context(struct asn1_data *data, bool *v, int context)
392 asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(context));
393 asn1_read_uint8(data, &tmp);
400 return !data->has_error;
403 /* check a BOOLEAN */
404 bool asn1_check_BOOLEAN(struct asn1_data *data, bool v)
408 asn1_read_uint8(data, &b);
409 if (b != ASN1_BOOLEAN) {
410 data->has_error = true;
413 asn1_read_uint8(data, &b);
415 data->has_error = true;
418 return !data->has_error;
422 /* load a struct asn1_data structure with a lump of data, ready to be parsed */
423 bool asn1_load(struct asn1_data *data, DATA_BLOB blob)
426 data->data = (uint8_t *)talloc_memdup(data, blob.data, blob.length);
428 data->has_error = true;
431 data->length = blob.length;
435 /* Peek into an ASN1 buffer, not advancing the pointer */
436 bool asn1_peek(struct asn1_data *data, void *p, int len)
441 if (len < 0 || data->ofs + len < data->ofs || data->ofs + len < len)
444 if (data->ofs + len > data->length) {
445 /* we need to mark the buffer as consumed, so the caller knows
446 this was an out of data error, and not a decode error */
447 data->ofs = data->length;
451 memcpy(p, data->data + data->ofs, len);
455 /* read from a ASN1 buffer, advancing the buffer pointer */
456 bool asn1_read(struct asn1_data *data, void *p, int len)
458 if (!asn1_peek(data, p, len)) {
459 data->has_error = true;
467 /* read a uint8_t from a ASN1 buffer */
468 bool asn1_read_uint8(struct asn1_data *data, uint8_t *v)
470 return asn1_read(data, v, 1);
473 bool asn1_peek_uint8(struct asn1_data *data, uint8_t *v)
475 return asn1_peek(data, v, 1);
478 bool asn1_peek_tag(struct asn1_data *data, uint8_t tag)
482 if (asn1_tag_remaining(data) <= 0) {
486 if (!asn1_peek_uint8(data, &b))
493 * just get the needed size the tag would consume
495 bool asn1_peek_tag_needed_size(struct asn1_data *data, uint8_t tag, size_t *size)
497 off_t start_ofs = data->ofs;
501 if (data->has_error) {
505 if (!asn1_read_uint8(data, &b)) {
506 data->ofs = start_ofs;
507 data->has_error = false;
512 data->ofs = start_ofs;
513 data->has_error = false;
517 if (!asn1_read_uint8(data, &b)) {
518 data->ofs = start_ofs;
519 data->has_error = false;
525 if (!asn1_read_uint8(data, &b)) {
526 data->ofs = start_ofs;
527 data->has_error = false;
532 if (!asn1_read_uint8(data, &b)) {
533 data->ofs = start_ofs;
534 data->has_error = false;
537 taglen = (taglen << 8) | b;
544 *size = (data->ofs - start_ofs) + taglen;
546 data->ofs = start_ofs;
547 data->has_error = false;
551 /* start reading a nested asn1 structure */
552 bool asn1_start_tag(struct asn1_data *data, uint8_t tag)
555 struct nesting *nesting;
557 if (!asn1_read_uint8(data, &b))
561 data->has_error = true;
564 nesting = talloc(data, struct nesting);
566 data->has_error = true;
570 if (!asn1_read_uint8(data, &b)) {
576 if (!asn1_read_uint8(data, &b))
580 if (!asn1_read_uint8(data, &b))
582 nesting->taglen = (nesting->taglen << 8) | b;
588 nesting->start = data->ofs;
589 nesting->next = data->nesting;
590 data->nesting = nesting;
591 if (asn1_tag_remaining(data) == -1) {
594 return !data->has_error;
597 /* stop reading a tag */
598 bool asn1_end_tag(struct asn1_data *data)
600 struct nesting *nesting;
602 /* make sure we read it all */
603 if (asn1_tag_remaining(data) != 0) {
604 data->has_error = true;
608 nesting = data->nesting;
611 data->has_error = true;
615 data->nesting = nesting->next;
616 talloc_free(nesting);
620 /* work out how many bytes are left in this nested tag */
621 int asn1_tag_remaining(struct asn1_data *data)
624 if (data->has_error) {
628 if (!data->nesting) {
629 data->has_error = true;
632 remaining = data->nesting->taglen - (data->ofs - data->nesting->start);
633 if (remaining > (data->length - data->ofs)) {
634 data->has_error = true;
641 * Internal implementation for reading binary OIDs
642 * Reading is done as far in the buffer as valid OID
643 * till buffer ends or not valid sub-identifier is found.
645 static bool _ber_read_OID_String_impl(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
646 const char **OID, size_t *bytes_eaten)
651 char *tmp_oid = NULL;
653 if (blob.length < 2) return false;
657 tmp_oid = talloc_asprintf(mem_ctx, "%u", b[0]/40);
658 if (!tmp_oid) goto nomem;
659 tmp_oid = talloc_asprintf_append_buffer(tmp_oid, ".%u", b[0]%40);
660 if (!tmp_oid) goto nomem;
662 if (bytes_eaten != NULL) {
666 for(i = 1, v = 0; i < blob.length; i++) {
667 v = (v<<7) | (b[i]&0x7f);
668 if ( ! (b[i] & 0x80)) {
669 tmp_oid = talloc_asprintf_append_buffer(tmp_oid, ".%u", v);
674 if (!tmp_oid) goto nomem;
684 /* read an object ID from a data blob */
685 bool ber_read_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob, const char **OID)
689 if (!_ber_read_OID_String_impl(mem_ctx, blob, OID, &bytes_eaten))
692 return (bytes_eaten == blob.length);
696 * Deserialize partial OID string.
697 * Partial OIDs are in the form:
701 bool ber_read_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob, const char **partial_oid)
705 char *identifier = NULL;
706 char *tmp_oid = NULL;
708 if (!_ber_read_OID_String_impl(mem_ctx, blob, (const char **)&tmp_oid, &bytes_eaten))
711 if (bytes_eaten < blob.length) {
712 bytes_left = blob.length - bytes_eaten;
713 identifier = hex_encode_talloc(mem_ctx, &blob.data[bytes_eaten], bytes_left);
714 if (!identifier) goto nomem;
716 *partial_oid = talloc_asprintf_append_buffer(tmp_oid, ":0x%s", identifier);
717 if (!*partial_oid) goto nomem;
718 TALLOC_FREE(identifier);
720 *partial_oid = tmp_oid;
726 TALLOC_FREE(identifier);
727 TALLOC_FREE(tmp_oid);
731 /* read an object ID from a ASN1 buffer */
732 bool asn1_read_OID(struct asn1_data *data, TALLOC_CTX *mem_ctx, const char **OID)
737 if (!asn1_start_tag(data, ASN1_OID)) return false;
739 len = asn1_tag_remaining(data);
741 data->has_error = true;
745 blob = data_blob(NULL, len);
747 data->has_error = true;
751 asn1_read(data, blob.data, len);
753 if (data->has_error) {
754 data_blob_free(&blob);
758 if (!ber_read_OID_String(mem_ctx, blob, OID)) {
759 data->has_error = true;
760 data_blob_free(&blob);
764 data_blob_free(&blob);
768 /* check that the next object ID is correct */
769 bool asn1_check_OID(struct asn1_data *data, const char *OID)
773 if (!asn1_read_OID(data, data, &id)) return false;
775 if (strcmp(id, OID) != 0) {
776 talloc_free(discard_const(id));
777 data->has_error = true;
780 talloc_free(discard_const(id));
784 /* read a LDAPString from a ASN1 buffer */
785 bool asn1_read_LDAPString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
788 len = asn1_tag_remaining(data);
790 data->has_error = true;
793 *s = talloc_array(mem_ctx, char, len+1);
795 data->has_error = true;
798 asn1_read(data, *s, len);
800 return !data->has_error;
804 /* read a GeneralString from a ASN1 buffer */
805 bool asn1_read_GeneralString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
807 if (!asn1_start_tag(data, ASN1_GENERAL_STRING)) return false;
808 if (!asn1_read_LDAPString(data, mem_ctx, s)) return false;
809 return asn1_end_tag(data);
813 /* read a octet string blob */
814 bool asn1_read_OctetString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob)
818 if (!asn1_start_tag(data, ASN1_OCTET_STRING)) return false;
819 len = asn1_tag_remaining(data);
821 data->has_error = true;
824 *blob = data_blob_talloc(mem_ctx, NULL, len+1);
826 data->has_error = true;
829 asn1_read(data, blob->data, len);
834 if (data->has_error) {
835 data_blob_free(blob);
836 *blob = data_blob_null;
842 bool asn1_read_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
846 if (!asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(num))) return false;
847 len = asn1_tag_remaining(data);
849 data->has_error = true;
852 *blob = data_blob(NULL, len);
853 if ((len != 0) && (!blob->data)) {
854 data->has_error = true;
857 asn1_read(data, blob->data, len);
859 return !data->has_error;
862 /* read an integer without tag*/
863 bool asn1_read_implicit_Integer(struct asn1_data *data, int *i)
868 while (!data->has_error && asn1_tag_remaining(data)>0) {
869 if (!asn1_read_uint8(data, &b)) return false;
872 return !data->has_error;
876 /* read an integer */
877 bool asn1_read_Integer(struct asn1_data *data, int *i)
881 if (!asn1_start_tag(data, ASN1_INTEGER)) return false;
882 if (!asn1_read_implicit_Integer(data, i)) return false;
883 return asn1_end_tag(data);
886 /* read a BIT STRING */
887 bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding)
891 if (!asn1_start_tag(data, ASN1_BIT_STRING)) return false;
892 len = asn1_tag_remaining(data);
894 data->has_error = true;
897 if (!asn1_read_uint8(data, padding)) return false;
899 *blob = data_blob_talloc(mem_ctx, NULL, len);
901 data->has_error = true;
904 if (asn1_read(data, blob->data, len - 1)) {
910 if (data->has_error) {
911 data_blob_free(blob);
912 *blob = data_blob_null;
919 /* read an integer */
920 bool asn1_read_enumerated(struct asn1_data *data, int *v)
924 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
925 while (!data->has_error && asn1_tag_remaining(data)>0) {
927 asn1_read_uint8(data, &b);
930 return asn1_end_tag(data);
933 /* check a enumerated value is correct */
934 bool asn1_check_enumerated(struct asn1_data *data, int v)
937 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
938 asn1_read_uint8(data, &b);
942 data->has_error = false;
944 return !data->has_error;
947 /* write an enumerated value to the stream */
948 bool asn1_write_enumerated(struct asn1_data *data, uint8_t v)
950 if (!asn1_push_tag(data, ASN1_ENUMERATED)) return false;
951 asn1_write_uint8(data, v);
953 return !data->has_error;
957 Get us the data just written without copying
959 bool asn1_blob(const struct asn1_data *asn1, DATA_BLOB *blob)
961 if (asn1->has_error) {
964 if (asn1->nesting != NULL) {
967 blob->data = asn1->data;
968 blob->length = asn1->length;
973 Fill in an asn1 struct without making a copy
975 void asn1_load_nocopy(struct asn1_data *data, uint8_t *buf, size_t len)
983 check if a ASN.1 blob is a full tag
985 NTSTATUS asn1_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
987 struct asn1_data *asn1 = asn1_init(NULL);
990 NT_STATUS_HAVE_NO_MEMORY(asn1);
992 asn1->data = blob.data;
993 asn1->length = blob.length;
994 asn1_start_tag(asn1, tag);
995 if (asn1->has_error) {
997 return STATUS_MORE_ENTRIES;
999 size = asn1_tag_remaining(asn1) + asn1->ofs;
1003 if (size > blob.length) {
1004 return STATUS_MORE_ENTRIES;
1007 *packet_size = size;
1008 return NT_STATUS_OK;
1011 NTSTATUS asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
1013 struct asn1_data asn1;
1018 asn1.data = blob.data;
1019 asn1.length = blob.length;
1021 ok = asn1_peek_tag_needed_size(&asn1, tag, &size);
1023 return STATUS_MORE_ENTRIES;
1026 if (size > blob.length) {
1027 *packet_size = size;
1028 return STATUS_MORE_ENTRIES;
1031 *packet_size = size;
1032 return NT_STATUS_OK;