source: trunk/server/libcli/security/sddl.c@ 1040

Last change on this file since 1040 was 745, checked in by Silvan Scherrer, 13 years ago

Samba Server: updated trunk to 3.6.0
File size: 16.2 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3
4 security descriptor description language functions
5
6 Copyright (C) Andrew Tridgell 2005
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
20*/
21
22#include "includes.h"
23#include "libcli/security/security.h"
24#include "librpc/gen_ndr/ndr_misc.h"
25#include "system/locale.h"
26
27struct flag_map {
28 const char *name;
29 uint32_t flag;
30};
31
32/*
33 map a series of letter codes into a uint32_t
34*/
35static bool sddl_map_flags(const struct flag_map *map, const char *str,
36 uint32_t *flags, size_t *len)
37{
38 const char *str0 = str;
39 if (len) *len = 0;
40 *flags = 0;
41 while (str[0] && isupper(str[0])) {
42 int i;
43 for (i=0;map[i].name;i++) {
44 size_t l = strlen(map[i].name);
45 if (strncmp(map[i].name, str, l) == 0) {
46 *flags |= map[i].flag;
47 str += l;
48 if (len) *len += l;
49 break;
50 }
51 }
52 if (map[i].name == NULL) {
53 DEBUG(1, ("Unknown flag - %s in %s\n", str, str0));
54 return false;
55 }
56 }
57 return true;
58}
59
60/*
61 a mapping between the 2 letter SID codes and sid strings
62*/
63static const struct {
64 const char *code;
65 const char *sid;
66 uint32_t rid;
67} sid_codes[] = {
68 { "WD", SID_WORLD },
69
70 { "CO", SID_CREATOR_OWNER },
71 { "CG", SID_CREATOR_GROUP },
72
73 { "NU", SID_NT_NETWORK },
74 { "IU", SID_NT_INTERACTIVE },
75 { "SU", SID_NT_SERVICE },
76 { "AN", SID_NT_ANONYMOUS },
77 { "ED", SID_NT_ENTERPRISE_DCS },
78 { "PS", SID_NT_SELF },
79 { "AU", SID_NT_AUTHENTICATED_USERS },
80 { "RC", SID_NT_RESTRICTED },
81 { "SY", SID_NT_SYSTEM },
82 { "LS", SID_NT_LOCAL_SERVICE },
83 { "NS", SID_NT_NETWORK_SERVICE },
84
85 { "BA", SID_BUILTIN_ADMINISTRATORS },
86 { "BU", SID_BUILTIN_USERS },
87 { "BG", SID_BUILTIN_GUESTS },
88 { "PU", SID_BUILTIN_POWER_USERS },
89 { "AO", SID_BUILTIN_ACCOUNT_OPERATORS },
90 { "SO", SID_BUILTIN_SERVER_OPERATORS },
91 { "PO", SID_BUILTIN_PRINT_OPERATORS },
92 { "BO", SID_BUILTIN_BACKUP_OPERATORS },
93 { "RE", SID_BUILTIN_REPLICATOR },
94 { "BR", SID_BUILTIN_RAS_SERVERS },
95 { "RU", SID_BUILTIN_PREW2K },
96 { "RD", SID_BUILTIN_REMOTE_DESKTOP_USERS },
97 { "NO", SID_BUILTIN_NETWORK_CONF_OPERATORS },
98 { "IF", SID_BUILTIN_INCOMING_FOREST_TRUST },
99
100 { "LA", NULL, DOMAIN_RID_ADMINISTRATOR },
101 { "LG", NULL, DOMAIN_RID_GUEST },
102 { "LK", NULL, DOMAIN_RID_KRBTGT },
103
104 { "ER", NULL, DOMAIN_RID_ENTERPRISE_READONLY_DCS },
105 { "DA", NULL, DOMAIN_RID_ADMINS },
106 { "DU", NULL, DOMAIN_RID_USERS },
107 { "DG", NULL, DOMAIN_RID_GUESTS },
108 { "DC", NULL, DOMAIN_RID_DOMAIN_MEMBERS },
109 { "DD", NULL, DOMAIN_RID_DCS },
110 { "CA", NULL, DOMAIN_RID_CERT_ADMINS },
111 { "SA", NULL, DOMAIN_RID_SCHEMA_ADMINS },
112 { "EA", NULL, DOMAIN_RID_ENTERPRISE_ADMINS },
113 { "PA", NULL, DOMAIN_RID_POLICY_ADMINS },
114 { "RO", NULL, DOMAIN_RID_READONLY_DCS },
115 { "RS", NULL, DOMAIN_RID_RAS_SERVERS }
116};
117
118/*
119 decode a SID
120 It can either be a special 2 letter code, or in S-* format
121*/
122static struct dom_sid *sddl_decode_sid(TALLOC_CTX *mem_ctx, const char **sddlp,
123 const struct dom_sid *domain_sid)
124{
125 const char *sddl = (*sddlp);
126 int i;
127
128 /* see if its in the numeric format */
129 if (strncmp(sddl, "S-", 2) == 0) {
130 struct dom_sid *sid;
131 char *sid_str;
132 size_t len = strspn(sddl+2, "-0123456789");
133 sid_str = talloc_strndup(mem_ctx, sddl, len+2);
134 if (!sid_str) {
135 return NULL;
136 }
137 (*sddlp) += len+2;
138 sid = dom_sid_parse_talloc(mem_ctx, sid_str);
139 talloc_free(sid_str);
140 return sid;
141 }
142
143 /* now check for one of the special codes */
144 for (i=0;i<ARRAY_SIZE(sid_codes);i++) {
145 if (strncmp(sid_codes[i].code, sddl, 2) == 0) break;
146 }
147 if (i == ARRAY_SIZE(sid_codes)) {
148 DEBUG(1,("Unknown sddl sid code '%2.2s'\n", sddl));
149 return NULL;
150 }
151
152 (*sddlp) += 2;
153
154 if (sid_codes[i].sid == NULL) {
155 return dom_sid_add_rid(mem_ctx, domain_sid, sid_codes[i].rid);
156 }
157
158 return dom_sid_parse_talloc(mem_ctx, sid_codes[i].sid);
159}
160
161static const struct flag_map ace_types[] = {
162 { "AU", SEC_ACE_TYPE_SYSTEM_AUDIT },
163 { "AL", SEC_ACE_TYPE_SYSTEM_ALARM },
164 { "OA", SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT },
165 { "OD", SEC_ACE_TYPE_ACCESS_DENIED_OBJECT },
166 { "OU", SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT },
167 { "OL", SEC_ACE_TYPE_SYSTEM_ALARM_OBJECT },
168 { "A", SEC_ACE_TYPE_ACCESS_ALLOWED },
169 { "D", SEC_ACE_TYPE_ACCESS_DENIED },
170 { NULL, 0 }
171};
172
173static const struct flag_map ace_flags[] = {
174 { "OI", SEC_ACE_FLAG_OBJECT_INHERIT },
175 { "CI", SEC_ACE_FLAG_CONTAINER_INHERIT },
176 { "NP", SEC_ACE_FLAG_NO_PROPAGATE_INHERIT },
177 { "IO", SEC_ACE_FLAG_INHERIT_ONLY },
178 { "ID", SEC_ACE_FLAG_INHERITED_ACE },
179 { "SA", SEC_ACE_FLAG_SUCCESSFUL_ACCESS },
180 { "FA", SEC_ACE_FLAG_FAILED_ACCESS },
181 { NULL, 0 },
182};
183
184static const struct flag_map ace_access_mask[] = {
185 { "RP", SEC_ADS_READ_PROP },
186 { "WP", SEC_ADS_WRITE_PROP },
187 { "CR", SEC_ADS_CONTROL_ACCESS },
188 { "CC", SEC_ADS_CREATE_CHILD },
189 { "DC", SEC_ADS_DELETE_CHILD },
190 { "LC", SEC_ADS_LIST },
191 { "LO", SEC_ADS_LIST_OBJECT },
192 { "RC", SEC_STD_READ_CONTROL },
193 { "WO", SEC_STD_WRITE_OWNER },
194 { "WD", SEC_STD_WRITE_DAC },
195 { "SD", SEC_STD_DELETE },
196 { "DT", SEC_ADS_DELETE_TREE },
197 { "SW", SEC_ADS_SELF_WRITE },
198 { "GA", SEC_GENERIC_ALL },
199 { "GR", SEC_GENERIC_READ },
200 { "GW", SEC_GENERIC_WRITE },
201 { "GX", SEC_GENERIC_EXECUTE },
202 { NULL, 0 }
203};
204
205/*
206 decode an ACE
207 return true on success, false on failure
208 note that this routine modifies the string
209*/
210static bool sddl_decode_ace(TALLOC_CTX *mem_ctx, struct security_ace *ace, char *str,
211 const struct dom_sid *domain_sid)
212{
213 const char *tok[6];
214 const char *s;
215 int i;
216 uint32_t v;
217 struct dom_sid *sid;
218
219 ZERO_STRUCTP(ace);
220
221 /* parse out the 6 tokens */
222 tok[0] = str;
223 for (i=0;i<5;i++) {
224 char *ptr = strchr(str, ';');
225 if (ptr == NULL) return false;
226 *ptr = 0;
227 str = ptr+1;
228 tok[i+1] = str;
229 }
230
231 /* parse ace type */
232 if (!sddl_map_flags(ace_types, tok[0], &v, NULL)) {
233 return false;
234 }
235 ace->type = v;
236
237 /* ace flags */
238 if (!sddl_map_flags(ace_flags, tok[1], &v, NULL)) {
239 return false;
240 }
241 ace->flags = v;
242
243 /* access mask */
244 if (strncmp(tok[2], "0x", 2) == 0) {
245 ace->access_mask = strtol(tok[2], NULL, 16);
246 } else {
247 if (!sddl_map_flags(ace_access_mask, tok[2], &v, NULL)) {
248 return false;
249 }
250 ace->access_mask = v;
251 }
252
253 /* object */
254 if (tok[3][0] != 0) {
255 NTSTATUS status = GUID_from_string(tok[3],
256 &ace->object.object.type.type);
257 if (!NT_STATUS_IS_OK(status)) {
258 return false;
259 }
260 ace->object.object.flags |= SEC_ACE_OBJECT_TYPE_PRESENT;
261 }
262
263 /* inherit object */
264 if (tok[4][0] != 0) {
265 NTSTATUS status = GUID_from_string(tok[4],
266 &ace->object.object.inherited_type.inherited_type);
267 if (!NT_STATUS_IS_OK(status)) {
268 return false;
269 }
270 ace->object.object.flags |= SEC_ACE_INHERITED_OBJECT_TYPE_PRESENT;
271 }
272
273 /* trustee */
274 s = tok[5];
275 sid = sddl_decode_sid(mem_ctx, &s, domain_sid);
276 if (sid == NULL) {
277 return false;
278 }
279 ace->trustee = *sid;
280 talloc_free(sid);
281
282 return true;
283}
284
285static const struct flag_map acl_flags[] = {
286 { "P", SEC_DESC_DACL_PROTECTED },
287 { "AR", SEC_DESC_DACL_AUTO_INHERIT_REQ },
288 { "AI", SEC_DESC_DACL_AUTO_INHERITED },
289 { NULL, 0 }
290};
291
292/*
293 decode an ACL
294*/
295static struct security_acl *sddl_decode_acl(struct security_descriptor *sd,
296 const char **sddlp, uint32_t *flags,
297 const struct dom_sid *domain_sid)
298{
299 const char *sddl = *sddlp;
300 struct security_acl *acl;
301 size_t len;
302
303 *flags = 0;
304
305 acl = talloc_zero(sd, struct security_acl);
306 if (acl == NULL) return NULL;
307 acl->revision = SECURITY_ACL_REVISION_ADS;
308
309 if (isupper(sddl[0]) && sddl[1] == ':') {
310 /* its an empty ACL */
311 return acl;
312 }
313
314 /* work out the ACL flags */
315 if (!sddl_map_flags(acl_flags, sddl, flags, &len)) {
316 talloc_free(acl);
317 return NULL;
318 }
319 sddl += len;
320
321 /* now the ACEs */
322 while (*sddl == '(') {
323 char *astr;
324 len = strcspn(sddl+1, ")");
325 astr = talloc_strndup(acl, sddl+1, len);
326 if (astr == NULL || sddl[len+1] != ')') {
327 talloc_free(acl);
328 return NULL;
329 }
330 acl->aces = talloc_realloc(acl, acl->aces, struct security_ace,
331 acl->num_aces+1);
332 if (acl->aces == NULL) {
333 talloc_free(acl);
334 return NULL;
335 }
336 if (!sddl_decode_ace(acl->aces, &acl->aces[acl->num_aces],
337 astr, domain_sid)) {
338 talloc_free(acl);
339 return NULL;
340 }
341 switch (acl->aces[acl->num_aces].type) {
342 case SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT:
343 case SEC_ACE_TYPE_ACCESS_DENIED_OBJECT:
344 case SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT:
345 case SEC_ACE_TYPE_SYSTEM_ALARM_OBJECT:
346 acl->revision = SECURITY_ACL_REVISION_ADS;
347 break;
348 default:
349 break;
350 }
351 talloc_free(astr);
352 sddl += len+2;
353 acl->num_aces++;
354 }
355
356 (*sddlp) = sddl;
357 return acl;
358}
359
360/*
361 decode a security descriptor in SDDL format
362*/
363struct security_descriptor *sddl_decode(TALLOC_CTX *mem_ctx, const char *sddl,
364 const struct dom_sid *domain_sid)
365{
366 struct security_descriptor *sd;
367 sd = talloc_zero(mem_ctx, struct security_descriptor);
368
369 sd->revision = SECURITY_DESCRIPTOR_REVISION_1;
370 sd->type = SEC_DESC_SELF_RELATIVE;
371
372 while (*sddl) {
373 uint32_t flags;
374 char c = sddl[0];
375 if (sddl[1] != ':') goto failed;
376
377 sddl += 2;
378 switch (c) {
379 case 'D':
380 if (sd->dacl != NULL) goto failed;
381 sd->dacl = sddl_decode_acl(sd, &sddl, &flags, domain_sid);
382 if (sd->dacl == NULL) goto failed;
383 sd->type |= flags | SEC_DESC_DACL_PRESENT;
384 break;
385 case 'S':
386 if (sd->sacl != NULL) goto failed;
387 sd->sacl = sddl_decode_acl(sd, &sddl, &flags, domain_sid);
388 if (sd->sacl == NULL) goto failed;
389 /* this relies on the SEC_DESC_SACL_* flags being
390 1 bit shifted from the SEC_DESC_DACL_* flags */
391 sd->type |= (flags<<1) | SEC_DESC_SACL_PRESENT;
392 break;
393 case 'O':
394 if (sd->owner_sid != NULL) goto failed;
395 sd->owner_sid = sddl_decode_sid(sd, &sddl, domain_sid);
396 if (sd->owner_sid == NULL) goto failed;
397 break;
398 case 'G':
399 if (sd->group_sid != NULL) goto failed;
400 sd->group_sid = sddl_decode_sid(sd, &sddl, domain_sid);
401 if (sd->group_sid == NULL) goto failed;
402 break;
403 }
404 }
405
406 return sd;
407
408failed:
409 DEBUG(2,("Badly formatted SDDL '%s'\n", sddl));
410 talloc_free(sd);
411 return NULL;
412}
413
414/*
415 turn a set of flags into a string
416*/
417static char *sddl_flags_to_string(TALLOC_CTX *mem_ctx, const struct flag_map *map,
418 uint32_t flags, bool check_all)
419{
420 int i;
421 char *s;
422
423 /* try to find an exact match */
424 for (i=0;map[i].name;i++) {
425 if (map[i].flag == flags) {
426 return talloc_strdup(mem_ctx, map[i].name);
427 }
428 }
429
430 s = talloc_strdup(mem_ctx, "");
431
432 /* now by bits */
433 for (i=0;map[i].name;i++) {
434 if ((flags & map[i].flag) != 0) {
435 s = talloc_asprintf_append_buffer(s, "%s", map[i].name);
436 if (s == NULL) goto failed;
437 flags &= ~map[i].flag;
438 }
439 }
440
441 if (check_all && flags != 0) {
442 goto failed;
443 }
444
445 return s;
446
447failed:
448 talloc_free(s);
449 return NULL;
450}
451
452/*
453 encode a sid in SDDL format
454*/
455static char *sddl_encode_sid(TALLOC_CTX *mem_ctx, const struct dom_sid *sid,
456 const struct dom_sid *domain_sid)
457{
458 int i;
459 char *sidstr;
460
461 sidstr = dom_sid_string(mem_ctx, sid);
462 if (sidstr == NULL) return NULL;
463
464 /* seen if its a well known sid */
465 for (i=0;sid_codes[i].sid;i++) {
466 if (strcmp(sidstr, sid_codes[i].sid) == 0) {
467 talloc_free(sidstr);
468 return talloc_strdup(mem_ctx, sid_codes[i].code);
469 }
470 }
471
472 /* or a well known rid in our domain */
473 if (dom_sid_in_domain(domain_sid, sid)) {
474 uint32_t rid = sid->sub_auths[sid->num_auths-1];
475 for (;i<ARRAY_SIZE(sid_codes);i++) {
476 if (rid == sid_codes[i].rid) {
477 talloc_free(sidstr);
478 return talloc_strdup(mem_ctx, sid_codes[i].code);
479 }
480 }
481 }
482
483 talloc_free(sidstr);
484
485 /* TODO: encode well known sids as two letter codes */
486 return dom_sid_string(mem_ctx, sid);
487}
488
489
490/*
491 encode an ACE in SDDL format
492*/
493static char *sddl_encode_ace(TALLOC_CTX *mem_ctx, const struct security_ace *ace,
494 const struct dom_sid *domain_sid)
495{
496 char *sddl = NULL;
497 TALLOC_CTX *tmp_ctx;
498 const char *sddl_type="", *sddl_flags="", *sddl_mask="",
499 *sddl_object="", *sddl_iobject="", *sddl_trustee="";
500
501 tmp_ctx = talloc_new(mem_ctx);
502 if (tmp_ctx == NULL) {
503 DEBUG(0, ("talloc_new failed\n"));
504 return NULL;
505 }
506
507 sddl_type = sddl_flags_to_string(tmp_ctx, ace_types, ace->type, true);
508 if (sddl_type == NULL) {
509 goto failed;
510 }
511
512 sddl_flags = sddl_flags_to_string(tmp_ctx, ace_flags, ace->flags,
513 true);
514 if (sddl_flags == NULL) {
515 goto failed;
516 }
517
518 sddl_mask = sddl_flags_to_string(tmp_ctx, ace_access_mask,
519 ace->access_mask, true);
520 if (sddl_mask == NULL) {
521 sddl_mask = talloc_asprintf(tmp_ctx, "0x%08x",
522 ace->access_mask);
523 if (sddl_mask == NULL) {
524 goto failed;
525 }
526 }
527
528 if (ace->type == SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT ||
529 ace->type == SEC_ACE_TYPE_ACCESS_DENIED_OBJECT ||
530 ace->type == SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT ||
531 ace->type == SEC_ACE_TYPE_SYSTEM_AUDIT_OBJECT) {
532 if (ace->object.object.flags & SEC_ACE_OBJECT_TYPE_PRESENT) {
533 sddl_object = GUID_string(
534 tmp_ctx, &ace->object.object.type.type);
535 if (sddl_object == NULL) {
536 goto failed;
537 }
538 }
539
540 if (ace->object.object.flags & SEC_ACE_INHERITED_OBJECT_TYPE_PRESENT) {
541 sddl_iobject = GUID_string(tmp_ctx, &ace->object.object.inherited_type.inherited_type);
542 if (sddl_iobject == NULL) {
543 goto failed;
544 }
545 }
546 }
547
548 sddl_trustee = sddl_encode_sid(tmp_ctx, &ace->trustee, domain_sid);
549 if (sddl_trustee == NULL) {
550 goto failed;
551 }
552
553 sddl = talloc_asprintf(mem_ctx, "%s;%s;%s;%s;%s;%s",
554 sddl_type, sddl_flags, sddl_mask, sddl_object,
555 sddl_iobject, sddl_trustee);
556
557failed:
558 talloc_free(tmp_ctx);
559 return sddl;
560}
561
562/*
563 encode an ACL in SDDL format
564*/
565static char *sddl_encode_acl(TALLOC_CTX *mem_ctx, const struct security_acl *acl,
566 uint32_t flags, const struct dom_sid *domain_sid)
567{
568 char *sddl;
569 uint32_t i;
570
571 /* add any ACL flags */
572 sddl = sddl_flags_to_string(mem_ctx, acl_flags, flags, false);
573 if (sddl == NULL) goto failed;
574
575 /* now the ACEs, encoded in braces */
576 for (i=0;i<acl->num_aces;i++) {
577 char *ace = sddl_encode_ace(sddl, &acl->aces[i], domain_sid);
578 if (ace == NULL) goto failed;
579 sddl = talloc_asprintf_append_buffer(sddl, "(%s)", ace);
580 if (sddl == NULL) goto failed;
581 talloc_free(ace);
582 }
583
584 return sddl;
585
586failed:
587 talloc_free(sddl);
588 return NULL;
589}
590
591
592/*
593 encode a security descriptor to SDDL format
594*/
595char *sddl_encode(TALLOC_CTX *mem_ctx, const struct security_descriptor *sd,
596 const struct dom_sid *domain_sid)
597{
598 char *sddl;
599 TALLOC_CTX *tmp_ctx;
600
601 /* start with a blank string */
602 sddl = talloc_strdup(mem_ctx, "");
603 if (sddl == NULL) goto failed;
604
605 tmp_ctx = talloc_new(mem_ctx);
606
607 if (sd->owner_sid != NULL) {
608 char *sid = sddl_encode_sid(tmp_ctx, sd->owner_sid, domain_sid);
609 if (sid == NULL) goto failed;
610 sddl = talloc_asprintf_append_buffer(sddl, "O:%s", sid);
611 if (sddl == NULL) goto failed;
612 }
613
614 if (sd->group_sid != NULL) {
615 char *sid = sddl_encode_sid(tmp_ctx, sd->group_sid, domain_sid);
616 if (sid == NULL) goto failed;
617 sddl = talloc_asprintf_append_buffer(sddl, "G:%s", sid);
618 if (sddl == NULL) goto failed;
619 }
620
621 if ((sd->type & SEC_DESC_DACL_PRESENT) && sd->dacl != NULL) {
622 char *acl = sddl_encode_acl(tmp_ctx, sd->dacl, sd->type, domain_sid);
623 if (acl == NULL) goto failed;
624 sddl = talloc_asprintf_append_buffer(sddl, "D:%s", acl);
625 if (sddl == NULL) goto failed;
626 }
627
628 if ((sd->type & SEC_DESC_SACL_PRESENT) && sd->sacl != NULL) {
629 char *acl = sddl_encode_acl(tmp_ctx, sd->sacl, sd->type>>1, domain_sid);
630 if (acl == NULL) goto failed;
631 sddl = talloc_asprintf_append_buffer(sddl, "S:%s", acl);
632 if (sddl == NULL) goto failed;
633 }
634
635 talloc_free(tmp_ctx);
636 return sddl;
637
638failed:
639 talloc_free(sddl);
640 return NULL;
641}
642
643
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