pyldb: avoid segfault when adding an element with no name
[nivanova/samba-autobuild/.git] / libgpo / gpo_sec.c
1 /*
2  *  Unix SMB/CIFS implementation.
3  *  Group Policy Object Support
4  *  Copyright (C) Guenther Deschner 2007
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 #include "includes.h"
21 #include "libcli/security/security.h"
22 #include "../libgpo/gpo.h"
23 #include "auth.h"
24 #include "../librpc/ndr/libndr.h"
25
26 /****************************************************************
27 ****************************************************************/
28
29 static bool gpo_sd_check_agp_object_guid(const struct security_ace_object *object)
30 {
31         struct GUID ext_right_apg_guid;
32         NTSTATUS status;
33
34         if (!object) {
35                 return false;
36         }
37
38         status = GUID_from_string(ADS_EXTENDED_RIGHT_APPLY_GROUP_POLICY,
39                                   &ext_right_apg_guid);
40         if (!NT_STATUS_IS_OK(status)) {
41                 return false;
42         }
43
44         switch (object->flags) {
45                 case SEC_ACE_OBJECT_TYPE_PRESENT:
46                         if (GUID_equal(&object->type.type,
47                                        &ext_right_apg_guid)) {
48                                 return true;
49                         }
50
51                         FALL_THROUGH;
52                 case SEC_ACE_INHERITED_OBJECT_TYPE_PRESENT:
53                         if (GUID_equal(&object->inherited_type.inherited_type,
54                                        &ext_right_apg_guid)) {
55                                 return true;
56                         }
57
58                         FALL_THROUGH;
59                 default:
60                         break;
61         }
62
63         return false;
64 }
65
66 /****************************************************************
67 ****************************************************************/
68
69 static bool gpo_sd_check_agp_object(const struct security_ace *ace)
70 {
71         if (!sec_ace_object(ace->type)) {
72                 return false;
73         }
74
75         return gpo_sd_check_agp_object_guid(&ace->object.object);
76 }
77
78 /****************************************************************
79 ****************************************************************/
80
81 static bool gpo_sd_check_agp_access_bits(uint32_t access_mask)
82 {
83         return (access_mask & SEC_ADS_CONTROL_ACCESS);
84 }
85
86 #if 0
87 /****************************************************************
88 ****************************************************************/
89
90 static bool gpo_sd_check_read_access_bits(uint32_t access_mask)
91 {
92         uint32_t read_bits = SEC_RIGHTS_LIST_CONTENTS |
93                            SEC_RIGHTS_READ_ALL_PROP |
94                            SEC_RIGHTS_READ_PERMS;
95
96         return (read_bits == (access_mask & read_bits));
97 }
98 #endif
99
100 /****************************************************************
101 ****************************************************************/
102
103 static NTSTATUS gpo_sd_check_ace_denied_object(const struct security_ace *ace,
104                                                const struct security_token *token)
105 {
106         if (gpo_sd_check_agp_object(ace) &&
107             gpo_sd_check_agp_access_bits(ace->access_mask) &&
108             security_token_has_sid(token, &ace->trustee)) {
109                 struct dom_sid_buf sid_str;
110                 DEBUG(10,("gpo_sd_check_ace_denied_object: "
111                         "Access denied as of ace for %s\n",
112                         dom_sid_str_buf(&ace->trustee, &sid_str)));
113                 return NT_STATUS_ACCESS_DENIED;
114         }
115
116         return STATUS_MORE_ENTRIES;
117 }
118
119 /****************************************************************
120 ****************************************************************/
121
122 static NTSTATUS gpo_sd_check_ace_allowed_object(const struct security_ace *ace,
123                                                 const struct security_token *token)
124 {
125         if (gpo_sd_check_agp_object(ace) &&
126             gpo_sd_check_agp_access_bits(ace->access_mask) &&
127             security_token_has_sid(token, &ace->trustee)) {
128                 struct dom_sid_buf sid_str;
129                 DEBUG(10,("gpo_sd_check_ace_allowed_object: "
130                         "Access granted as of ace for %s\n",
131                         dom_sid_str_buf(&ace->trustee, &sid_str)));
132                 return NT_STATUS_OK;
133         }
134
135         return STATUS_MORE_ENTRIES;
136 }
137
138 /****************************************************************
139 ****************************************************************/
140
141 static NTSTATUS gpo_sd_check_ace(const struct security_ace *ace,
142                                  const struct security_token *token)
143 {
144         switch (ace->type) {
145                 case SEC_ACE_TYPE_ACCESS_DENIED_OBJECT:
146                         return gpo_sd_check_ace_denied_object(ace, token);
147                 case SEC_ACE_TYPE_ACCESS_ALLOWED_OBJECT:
148                         return gpo_sd_check_ace_allowed_object(ace, token);
149                 default:
150                         return STATUS_MORE_ENTRIES;
151         }
152 }
153
154 /****************************************************************
155 ****************************************************************/
156
157 NTSTATUS gpo_apply_security_filtering(const struct GROUP_POLICY_OBJECT *gpo,
158                                       const struct security_token *token)
159 {
160         struct security_descriptor *sd = gpo->security_descriptor;
161         struct security_acl *dacl = NULL;
162         NTSTATUS status = NT_STATUS_ACCESS_DENIED;
163         int i;
164
165         if (!token) {
166                 return NT_STATUS_INVALID_USER_BUFFER;
167         }
168
169         if (!sd) {
170                 return NT_STATUS_INVALID_SECURITY_DESCR;
171         }
172
173         dacl = sd->dacl;
174         if (!dacl) {
175                 return NT_STATUS_INVALID_SECURITY_DESCR;
176         }
177
178         /* check all aces and only return NT_STATUS_OK (== Access granted) or
179          * NT_STATUS_ACCESS_DENIED ( == Access denied) - the default is to
180          * deny access */
181
182         for (i = 0; i < dacl->num_aces; i ++) {
183
184                 status = gpo_sd_check_ace(&dacl->aces[i], token);
185
186                 if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
187                         return status;
188                 } else if (NT_STATUS_IS_OK(status)) {
189                         return status;
190                 }
191
192                 continue;
193         }
194
195         return NT_STATUS_ACCESS_DENIED;
196 }