s3:smbd: s/struct timed_event/struct tevent_timer
[Samba/gebeck_regimport.git] / source3 / smbd / file_access.c
blobf4a7bb3d45ae3b236224017ba8126754bcc20069
1 /*
2 Unix SMB/CIFS implementation.
3 Check access to files based on security descriptors.
4 Copyright (C) Jeremy Allison 2005-2006.
5 Copyright (C) Michael Adam 2007.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "includes.h"
22 #include "system/filesys.h"
23 #include "../libcli/security/security.h"
24 #include "../librpc/gen_ndr/ndr_security.h"
25 #include "smbd/smbd.h"
27 #undef DBGC_CLASS
28 #define DBGC_CLASS DBGC_ACLS
30 /****************************************************************************
31 Actually emulate the in-kernel access checking for delete access. We need
32 this to successfully return ACCESS_DENIED on a file open for delete access.
33 ****************************************************************************/
35 bool can_delete_file_in_directory(connection_struct *conn,
36 const struct smb_filename *smb_fname)
38 TALLOC_CTX *ctx = talloc_tos();
39 char *dname = NULL;
40 struct smb_filename *smb_fname_parent = NULL;
41 NTSTATUS status;
42 bool ret;
44 if (!CAN_WRITE(conn)) {
45 return False;
48 if (!lp_acl_check_permissions(SNUM(conn))) {
49 /* This option means don't check. */
50 return true;
53 /* Get the parent directory permission mask and owners. */
54 if (!parent_dirname(ctx, smb_fname->base_name, &dname, NULL)) {
55 return False;
58 status = create_synthetic_smb_fname(ctx, dname, NULL, NULL,
59 &smb_fname_parent);
60 if (!NT_STATUS_IS_OK(status)) {
61 ret = false;
62 goto out;
65 if(SMB_VFS_STAT(conn, smb_fname_parent) != 0) {
66 ret = false;
67 goto out;
70 /* fast paths first */
72 if (!S_ISDIR(smb_fname_parent->st.st_ex_mode)) {
73 ret = false;
74 goto out;
76 if (get_current_uid(conn) == (uid_t)0) {
77 /* I'm sorry sir, I didn't know you were root... */
78 ret = true;
79 goto out;
82 #ifdef S_ISVTX
83 /* sticky bit means delete only by owner of file or by root or
84 * by owner of directory. */
85 if (smb_fname_parent->st.st_ex_mode & S_ISVTX) {
86 if (!VALID_STAT(smb_fname->st)) {
87 /* If the file doesn't already exist then
88 * yes we'll be able to delete it. */
89 ret = true;
90 goto out;
94 * Patch from SATOH Fumiyasu <fumiyas@miraclelinux.com>
95 * for bug #3348. Don't assume owning sticky bit
96 * directory means write access allowed.
97 * Fail to delete if we're not the owner of the file,
98 * or the owner of the directory as we have no possible
99 * chance of deleting. Otherwise, go on and check the ACL.
101 if ((get_current_uid(conn) !=
102 smb_fname_parent->st.st_ex_uid) &&
103 (get_current_uid(conn) != smb_fname->st.st_ex_uid)) {
104 DEBUG(10,("can_delete_file_in_directory: not "
105 "owner of file %s or directory %s",
106 smb_fname_str_dbg(smb_fname),
107 smb_fname_str_dbg(smb_fname_parent)));
108 ret = false;
109 goto out;
112 #endif
114 /* now for ACL checks */
117 * There's two ways to get the permission to delete a file: First by
118 * having the DELETE bit on the file itself and second if that does
119 * not help, by the DELETE_CHILD bit on the containing directory.
121 * Here we only check the directory permissions, we will
122 * check the file DELETE permission separately.
125 ret = NT_STATUS_IS_OK(smbd_check_access_rights(conn,
126 smb_fname_parent,
127 false,
128 FILE_DELETE_CHILD));
129 out:
130 TALLOC_FREE(dname);
131 TALLOC_FREE(smb_fname_parent);
132 return ret;
135 /****************************************************************************
136 Userspace check for write access.
137 ****************************************************************************/
139 bool can_write_to_file(connection_struct *conn,
140 const struct smb_filename *smb_fname)
142 return NT_STATUS_IS_OK(smbd_check_access_rights(conn,
143 smb_fname,
144 false,
145 FILE_WRITE_DATA));
148 /****************************************************************************
149 Check for an existing default Windows ACL on a directory.
150 ****************************************************************************/
152 bool directory_has_default_acl(connection_struct *conn, const char *fname)
154 struct security_descriptor *secdesc = NULL;
155 unsigned int i;
156 NTSTATUS status = SMB_VFS_GET_NT_ACL(conn, fname,
157 SECINFO_DACL, talloc_tos(),
158 &secdesc);
160 if (!NT_STATUS_IS_OK(status) ||
161 secdesc == NULL ||
162 secdesc->dacl == NULL) {
163 TALLOC_FREE(secdesc);
164 return false;
167 for (i = 0; i < secdesc->dacl->num_aces; i++) {
168 struct security_ace *psa = &secdesc->dacl->aces[i];
169 if (psa->flags & (SEC_ACE_FLAG_OBJECT_INHERIT|
170 SEC_ACE_FLAG_CONTAINER_INHERIT)) {
171 TALLOC_FREE(secdesc);
172 return true;
175 TALLOC_FREE(secdesc);
176 return false;
179 /****************************************************************************
180 Check if setting delete on close is allowed on this fsp.
181 ****************************************************************************/
183 NTSTATUS can_set_delete_on_close(files_struct *fsp, uint32 dosmode)
186 * Only allow delete on close for writable files.
189 if ((dosmode & FILE_ATTRIBUTE_READONLY) &&
190 !lp_delete_readonly(SNUM(fsp->conn))) {
191 DEBUG(10,("can_set_delete_on_close: file %s delete on close "
192 "flag set but file attribute is readonly.\n",
193 fsp_str_dbg(fsp)));
194 return NT_STATUS_CANNOT_DELETE;
198 * Only allow delete on close for writable shares.
201 if (!CAN_WRITE(fsp->conn)) {
202 DEBUG(10,("can_set_delete_on_close: file %s delete on "
203 "close flag set but write access denied on share.\n",
204 fsp_str_dbg(fsp)));
205 return NT_STATUS_ACCESS_DENIED;
209 * Only allow delete on close for files/directories opened with delete
210 * intent.
213 if (!(fsp->access_mask & DELETE_ACCESS)) {
214 DEBUG(10,("can_set_delete_on_close: file %s delete on "
215 "close flag set but delete access denied.\n",
216 fsp_str_dbg(fsp)));
217 return NT_STATUS_ACCESS_DENIED;
220 /* Don't allow delete on close for non-empty directories. */
221 if (fsp->is_directory) {
222 SMB_ASSERT(!is_ntfs_stream_smb_fname(fsp->fsp_name));
224 /* Or the root of a share. */
225 if (ISDOT(fsp->fsp_name->base_name)) {
226 DEBUG(10,("can_set_delete_on_close: can't set delete on "
227 "close for the root of a share.\n"));
228 return NT_STATUS_ACCESS_DENIED;
231 return can_delete_directory_fsp(fsp);
234 return NT_STATUS_OK;