cce504dc97713113d309728ccba796fc169d0f3f
[amitay/samba.git] / source4 / dsdb / samdb / ldb_modules / acl_util.c
1 /*
2   ACL utility functions
3
4   Copyright (C) Nadezhda Ivanova 2010
5
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.
10
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.
15
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/>.
18 */
19
20 /*
21  *  Name: acl_util
22  *
23  *  Component: ldb ACL modules
24  *
25  *  Description: Some auxiliary functions used for access checking
26  *
27  *  Author: Nadezhda Ivanova
28  */
29 #include "includes.h"
30 #include "ldb_module.h"
31 #include "auth/auth.h"
32 #include "libcli/security/security.h"
33 #include "dsdb/samdb/samdb.h"
34 #include "librpc/gen_ndr/ndr_security.h"
35 #include "param/param.h"
36 #include "dsdb/samdb/ldb_modules/util.h"
37
38 struct security_token *acl_user_token(struct ldb_module *module)
39 {
40         struct ldb_context *ldb = ldb_module_get_ctx(module);
41         struct auth_session_info *session_info
42                 = (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
43         if(!session_info) {
44                 return NULL;
45         }
46         return session_info->security_token;
47 }
48
49 /* performs an access check from inside the module stack
50  * given the dn of the object to be checked, the required access
51  * guid is either the guid of the extended right, or NULL
52  */
53
54 int dsdb_module_check_access_on_dn(struct ldb_module *module,
55                                    TALLOC_CTX *mem_ctx,
56                                    struct ldb_dn *dn,
57                                    uint32_t access_mask,
58                                    const struct GUID *guid,
59                                    struct ldb_request *parent)
60 {
61         int ret;
62         struct ldb_result *acl_res;
63         static const char *acl_attrs[] = {
64                 "nTSecurityDescriptor",
65                 "objectSid",
66                 NULL
67         };
68         struct ldb_context *ldb = ldb_module_get_ctx(module);
69         struct auth_session_info *session_info
70                 = (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
71         if(!session_info) {
72                 return ldb_operr(ldb);
73         }
74         ret = dsdb_module_search_dn(module, mem_ctx, &acl_res, dn,
75                                     acl_attrs,
76                                     DSDB_FLAG_NEXT_MODULE |
77                                     DSDB_SEARCH_SHOW_RECYCLED,
78                                     parent);
79         if (ret != LDB_SUCCESS) {
80                 DEBUG(0,("access_check: failed to find object %s\n", ldb_dn_get_linearized(dn)));
81                 return ret;
82         }
83         return dsdb_check_access_on_dn_internal(ldb, acl_res,
84                                                 mem_ctx,
85                                                 session_info->security_token,
86                                                 dn,
87                                                 access_mask,
88                                                 guid);
89 }
90
91 int acl_check_access_on_attribute(struct ldb_module *module,
92                                   TALLOC_CTX *mem_ctx,
93                                   struct security_descriptor *sd,
94                                   struct dom_sid *rp_sid,
95                                   uint32_t access_mask,
96                                   const struct dsdb_attribute *attr)
97 {
98         int ret;
99         NTSTATUS status;
100         uint32_t access_granted;
101         struct object_tree *root = NULL;
102         struct object_tree *new_node = NULL;
103         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
104         struct security_token *token = acl_user_token(module);
105         if (attr) {
106                 if (!GUID_all_zero(&attr->attributeSecurityGUID)) {
107                         if (!insert_in_object_tree(tmp_ctx,
108                                                    &attr->attributeSecurityGUID,
109                                                    access_mask, &root,
110                                                    &new_node)) {
111                                 DEBUG(10, ("acl_search: cannot add to object tree securityGUID\n"));
112                                 goto fail;
113                         }
114
115                         if (!insert_in_object_tree(tmp_ctx,
116                                                    &attr->schemaIDGUID,
117                                                    access_mask, &new_node,
118                                                    &new_node)) {
119                                 DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
120                                 goto fail;
121                         }
122                 }
123                 else {
124                         if (!insert_in_object_tree(tmp_ctx,
125                                                    &attr->schemaIDGUID,
126                                                    access_mask, &root,
127                                                    &new_node)) {
128                                 DEBUG(10, ("acl_search: cannot add to object tree attributeGUID\n"));
129                                 goto fail;
130                         }
131                 }
132         }
133         status = sec_access_check_ds(sd, token,
134                                      access_mask,
135                                      &access_granted,
136                                      root,
137                                      rp_sid);
138         if (!NT_STATUS_IS_OK(status)) {
139                 ret = LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
140         }
141         else {
142                 ret = LDB_SUCCESS;
143         }
144         talloc_free(tmp_ctx);
145         return ret;
146 fail:
147         talloc_free(tmp_ctx);
148         return ldb_operr(ldb_module_get_ctx(module));
149 }
150
151
152 /* checks for validated writes */
153 int acl_check_extended_right(TALLOC_CTX *mem_ctx,
154                              struct security_descriptor *sd,
155                              struct security_token *token,
156                              const char *ext_right,
157                              uint32_t right_type,
158                              struct dom_sid *sid)
159 {
160         struct GUID right;
161         NTSTATUS status;
162         uint32_t access_granted;
163         struct object_tree *root = NULL;
164         struct object_tree *new_node = NULL;
165         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
166
167         GUID_from_string(ext_right, &right);
168
169         if (!insert_in_object_tree(tmp_ctx, &right, right_type,
170                                    &root, &new_node)) {
171                 DEBUG(10, ("acl_ext_right: cannot add to object tree\n"));
172                 talloc_free(tmp_ctx);
173                 return LDB_ERR_OPERATIONS_ERROR;
174         }
175         status = sec_access_check_ds(sd, token,
176                                      right_type,
177                                      &access_granted,
178                                      root,
179                                      sid);
180
181         if (!NT_STATUS_IS_OK(status)) {
182                 talloc_free(tmp_ctx);
183                 return LDB_ERR_INSUFFICIENT_ACCESS_RIGHTS;
184         }
185         talloc_free(tmp_ctx);
186         return LDB_SUCCESS;
187 }
188
189 const char *acl_user_name(TALLOC_CTX *mem_ctx, struct ldb_module *module)
190 {
191         struct ldb_context *ldb = ldb_module_get_ctx(module);
192         struct auth_session_info *session_info
193                 = (struct auth_session_info *)ldb_get_opaque(ldb, "sessionInfo");
194         if (!session_info) {
195                 return "UNKNOWN (NULL)";
196         }
197
198         return talloc_asprintf(mem_ctx, "%s\\%s",
199                                session_info->info->domain_name,
200                                session_info->info->account_name);
201 }