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 if (!isdigit(*p)) return false;
225 v = strtoul(p, &newp, 10);
226 if (newp[0] != '.') return false;
229 if (!isdigit(*p)) return false;
230 v2 = strtoul(p, &newp, 10);
231 if (newp[0] != '.') return false;
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;
242 if (!isdigit(*p)) return false;
243 v = strtoul(p, &newp, 10);
244 if (newp[0] == '.') {
246 /* check for empty last component */
247 if (!*p) return false;
248 } else if (newp[0] == '\0') {
251 data_blob_free(blob);
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);
267 * Serialize partial OID string.
268 * Partial OIDs are in the form:
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);
278 /* truncate partial part so ber_write_OID_String() works */
279 p = strchr(oid, ':');
285 if (!ber_write_OID_String(mem_ctx, blob, oid)) {
286 talloc_free(tmp_ctx);
290 /* Add partially encoded sub-identifier */
292 DATA_BLOB tmp_blob = strhex_to_data_blob(tmp_ctx, p);
293 if (!data_blob_append(mem_ctx, blob, tmp_blob.data,
295 talloc_free(tmp_ctx);
300 talloc_free(tmp_ctx);
305 /* write an object ID to a ASN1 buffer */
306 bool asn1_write_OID(struct asn1_data *data, const char *OID)
310 if (!asn1_push_tag(data, ASN1_OID)) return false;
312 if (!ber_write_OID_String(NULL, &blob, OID)) {
313 data->has_error = true;
317 if (!asn1_write(data, blob.data, blob.length)) {
318 data_blob_free(&blob);
319 data->has_error = true;
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);
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);
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);
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);
372 return !data->has_error;
375 bool asn1_read_BOOLEAN(struct asn1_data *data, bool *v)
378 asn1_start_tag(data, ASN1_BOOLEAN);
379 asn1_read_uint8(data, &tmp);
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);
395 return !data->has_error;
398 bool asn1_read_BOOLEAN_context(struct asn1_data *data, bool *v, int context)
401 asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(context));
402 asn1_read_uint8(data, &tmp);
409 return !data->has_error;
412 /* check a BOOLEAN */
413 bool asn1_check_BOOLEAN(struct asn1_data *data, bool v)
417 asn1_read_uint8(data, &b);
418 if (b != ASN1_BOOLEAN) {
419 data->has_error = true;
422 asn1_read_uint8(data, &b);
424 data->has_error = true;
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)
435 data->data = (uint8_t *)talloc_memdup(data, blob.data, blob.length);
437 data->has_error = true;
440 data->length = blob.length;
444 /* Peek into an ASN1 buffer, not advancing the pointer */
445 bool asn1_peek(struct asn1_data *data, void *p, int len)
450 if (len < 0 || data->ofs + len < data->ofs || data->ofs + len < len)
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;
460 memcpy(p, data->data + data->ofs, len);
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;
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)
491 if (asn1_tag_remaining(data) <= 0) {
495 if (!asn1_peek_uint8(data, &b))
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;
510 if (data->has_error) {
514 if (!asn1_read_uint8(data, &b)) {
515 data->ofs = start_ofs;
516 data->has_error = false;
521 data->ofs = start_ofs;
522 data->has_error = false;
526 if (!asn1_read_uint8(data, &b)) {
527 data->ofs = start_ofs;
528 data->has_error = false;
534 if (!asn1_read_uint8(data, &b)) {
535 data->ofs = start_ofs;
536 data->has_error = false;
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;
553 if (!asn1_read_uint8(data, &b)) {
554 data->ofs = start_ofs;
555 data->has_error = false;
558 taglen = (taglen << 8) | b;
565 *size = (data->ofs - start_ofs) + taglen;
567 data->ofs = start_ofs;
568 data->has_error = false;
572 /* start reading a nested asn1 structure */
573 bool asn1_start_tag(struct asn1_data *data, uint8_t tag)
576 struct nesting *nesting;
578 if (!asn1_read_uint8(data, &b))
582 data->has_error = true;
585 nesting = talloc(data, struct nesting);
587 data->has_error = true;
591 if (!asn1_read_uint8(data, &b)) {
597 if (!asn1_read_uint8(data, &b))
601 if (!asn1_read_uint8(data, &b))
603 nesting->taglen = (nesting->taglen << 8) | b;
609 nesting->start = data->ofs;
610 nesting->next = data->nesting;
611 data->nesting = nesting;
612 if (asn1_tag_remaining(data) == -1) {
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;
629 nesting = data->nesting;
632 data->has_error = true;
636 data->nesting = nesting->next;
637 talloc_free(nesting);
641 /* work out how many bytes are left in this nested tag */
642 int asn1_tag_remaining(struct asn1_data *data)
645 if (data->has_error) {
649 if (!data->nesting) {
650 data->has_error = true;
653 remaining = data->nesting->taglen - (data->ofs - data->nesting->start);
654 if (remaining > (data->length - data->ofs)) {
655 data->has_error = true;
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)
672 char *tmp_oid = NULL;
674 if (blob.length < 2) return false;
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) {
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);
695 if (!tmp_oid) goto nomem;
705 /* read an object ID from a data blob */
706 bool ber_read_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob, char **OID)
710 if (!_ber_read_OID_String_impl(mem_ctx, blob, OID, &bytes_eaten))
713 return (bytes_eaten == blob.length);
717 * Deserialize partial OID string.
718 * Partial OIDs are in the form:
722 bool ber_read_partial_OID_String(TALLOC_CTX *mem_ctx, DATA_BLOB blob,
727 char *identifier = NULL;
728 char *tmp_oid = NULL;
730 if (!_ber_read_OID_String_impl(mem_ctx, blob, &tmp_oid, &bytes_eaten))
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);
742 *partial_oid = tmp_oid;
748 TALLOC_FREE(identifier);
749 TALLOC_FREE(tmp_oid);
753 /* read an object ID from a ASN1 buffer */
754 bool asn1_read_OID(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **OID)
759 if (!asn1_start_tag(data, ASN1_OID)) return false;
761 len = asn1_tag_remaining(data);
763 data->has_error = true;
767 blob = data_blob(NULL, len);
769 data->has_error = true;
773 asn1_read(data, blob.data, len);
775 if (data->has_error) {
776 data_blob_free(&blob);
780 if (!ber_read_OID_String(mem_ctx, blob, OID)) {
781 data->has_error = true;
782 data_blob_free(&blob);
786 data_blob_free(&blob);
790 /* check that the next object ID is correct */
791 bool asn1_check_OID(struct asn1_data *data, const char *OID)
795 if (!asn1_read_OID(data, data, &id)) return false;
797 if (strcmp(id, OID) != 0) {
799 data->has_error = true;
806 /* read a LDAPString from a ASN1 buffer */
807 bool asn1_read_LDAPString(struct asn1_data *data, TALLOC_CTX *mem_ctx, char **s)
810 len = asn1_tag_remaining(data);
812 data->has_error = true;
815 *s = talloc_array(mem_ctx, char, len+1);
817 data->has_error = true;
820 asn1_read(data, *s, len);
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)
840 if (!asn1_start_tag(data, ASN1_OCTET_STRING)) return false;
841 len = asn1_tag_remaining(data);
843 data->has_error = true;
846 *blob = data_blob_talloc(mem_ctx, NULL, len+1);
848 data->has_error = true;
851 asn1_read(data, blob->data, len);
856 if (data->has_error) {
857 data_blob_free(blob);
858 *blob = data_blob_null;
864 bool asn1_read_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob)
868 if (!asn1_start_tag(data, ASN1_CONTEXT_SIMPLE(num))) return false;
869 len = asn1_tag_remaining(data);
871 data->has_error = true;
874 *blob = data_blob(NULL, len);
875 if ((len != 0) && (!blob->data)) {
876 data->has_error = true;
879 asn1_read(data, blob->data, len);
881 return !data->has_error;
884 /* read an integer without tag*/
885 bool asn1_read_implicit_Integer(struct asn1_data *data, int *i)
890 while (!data->has_error && asn1_tag_remaining(data)>0) {
891 if (!asn1_read_uint8(data, &b)) return false;
894 return !data->has_error;
898 /* read an integer */
899 bool asn1_read_Integer(struct asn1_data *data, int *i)
903 if (!asn1_start_tag(data, ASN1_INTEGER)) return false;
904 if (!asn1_read_implicit_Integer(data, i)) return false;
905 return asn1_end_tag(data);
908 /* read a BIT STRING */
909 bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding)
913 if (!asn1_start_tag(data, ASN1_BIT_STRING)) return false;
914 len = asn1_tag_remaining(data);
916 data->has_error = true;
919 if (!asn1_read_uint8(data, padding)) return false;
921 *blob = data_blob_talloc(mem_ctx, NULL, len);
923 data->has_error = true;
926 if (asn1_read(data, blob->data, len - 1)) {
932 if (data->has_error) {
933 data_blob_free(blob);
934 *blob = data_blob_null;
941 /* read an integer */
942 bool asn1_read_enumerated(struct asn1_data *data, int *v)
946 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
947 while (!data->has_error && asn1_tag_remaining(data)>0) {
949 asn1_read_uint8(data, &b);
952 return asn1_end_tag(data);
955 /* check a enumerated value is correct */
956 bool asn1_check_enumerated(struct asn1_data *data, int v)
959 if (!asn1_start_tag(data, ASN1_ENUMERATED)) return false;
960 asn1_read_uint8(data, &b);
964 data->has_error = false;
966 return !data->has_error;
969 /* write an enumerated value to the stream */
970 bool asn1_write_enumerated(struct asn1_data *data, uint8_t v)
972 if (!asn1_push_tag(data, ASN1_ENUMERATED)) return false;
973 asn1_write_uint8(data, v);
975 return !data->has_error;
979 Get us the data just written without copying
981 bool asn1_blob(const struct asn1_data *asn1, DATA_BLOB *blob)
983 if (asn1->has_error) {
986 if (asn1->nesting != NULL) {
989 blob->data = asn1->data;
990 blob->length = asn1->length;
995 Fill in an asn1 struct without making a copy
997 void asn1_load_nocopy(struct asn1_data *data, uint8_t *buf, size_t len)
1005 check if a ASN.1 blob is a full tag
1007 NTSTATUS asn1_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
1009 struct asn1_data *asn1 = asn1_init(NULL);
1012 NT_STATUS_HAVE_NO_MEMORY(asn1);
1014 asn1->data = blob.data;
1015 asn1->length = blob.length;
1016 asn1_start_tag(asn1, tag);
1017 if (asn1->has_error) {
1019 return STATUS_MORE_ENTRIES;
1021 size = asn1_tag_remaining(asn1) + asn1->ofs;
1025 if (size > blob.length) {
1026 return STATUS_MORE_ENTRIES;
1029 *packet_size = size;
1030 return NT_STATUS_OK;
1033 NTSTATUS asn1_peek_full_tag(DATA_BLOB blob, uint8_t tag, size_t *packet_size)
1035 struct asn1_data asn1;
1040 asn1.data = blob.data;
1041 asn1.length = blob.length;
1043 ok = asn1_peek_tag_needed_size(&asn1, tag, &size);
1045 return NT_STATUS_INVALID_BUFFER_SIZE;
1048 if (size > blob.length) {
1049 *packet_size = size;
1050 return STATUS_MORE_ENTRIES;
1053 *packet_size = size;
1054 return NT_STATUS_OK;