eee4d896931790df2a78bac36044639baa6f7189
[samba.git] / source3 / modules / vfs_acl_tdb.c
1 /*
2  * Store Windows ACLs in a tdb.
3  *
4  * Copyright (C) Volker Lendecke, 2008
5  * Copyright (C) Jeremy Allison, 2008
6  *
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.
11  *
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.
16  *
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/>.
19  */
20
21 #include "includes.h"
22 #include "smbd/smbd.h"
23 #include "system/filesys.h"
24 #include "librpc/gen_ndr/xattr.h"
25 #include "librpc/gen_ndr/ndr_xattr.h"
26 #include "../lib/crypto/sha256.h"
27 #include "dbwrap/dbwrap.h"
28 #include "dbwrap/dbwrap_open.h"
29 #include "auth.h"
30 #include "util_tdb.h"
31
32 #undef DBGC_CLASS
33 #define DBGC_CLASS DBGC_VFS
34
35 #define ACL_MODULE_NAME "acl_tdb"
36 #include "modules/vfs_acl_common.c"
37
38 static unsigned int ref_count;
39 static struct db_context *acl_db;
40
41 /*******************************************************************
42  Open acl_db if not already open, increment ref count.
43 *******************************************************************/
44
45 static bool acl_tdb_init(void)
46 {
47         char *dbname;
48
49         if (acl_db) {
50                 ref_count++;
51                 return true;
52         }
53
54         dbname = state_path("file_ntacls.tdb");
55
56         if (dbname == NULL) {
57                 errno = ENOSYS;
58                 return false;
59         }
60
61         become_root();
62         acl_db = db_open(NULL, dbname, 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
63                          DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
64         unbecome_root();
65
66         if (acl_db == NULL) {
67 #if defined(ENOTSUP)
68                 errno = ENOTSUP;
69 #else
70                 errno = ENOSYS;
71 #endif
72                 TALLOC_FREE(dbname);
73                 return false;
74         }
75
76         ref_count++;
77         TALLOC_FREE(dbname);
78         return true;
79 }
80
81 /*******************************************************************
82  Lower ref count and close acl_db if zero.
83 *******************************************************************/
84
85 static void disconnect_acl_tdb(struct vfs_handle_struct *handle)
86 {
87         SMB_VFS_NEXT_DISCONNECT(handle);
88         ref_count--;
89         if (ref_count == 0) {
90                 TALLOC_FREE(acl_db);
91         }
92 }
93
94 /*******************************************************************
95  Fetch_lock the tdb acl record for a file
96 *******************************************************************/
97
98 static struct db_record *acl_tdb_lock(TALLOC_CTX *mem_ctx,
99                                         struct db_context *db,
100                                         const struct file_id *id)
101 {
102         uint8_t id_buf[16];
103
104         /* For backwards compatibility only store the dev/inode. */
105         push_file_id_16((char *)id_buf, id);
106         return dbwrap_fetch_locked(db,
107                                    mem_ctx,
108                                    make_tdb_data(id_buf,
109                                                  sizeof(id_buf)));
110 }
111
112 /*******************************************************************
113  Delete the tdb acl record for a file
114 *******************************************************************/
115
116 static NTSTATUS acl_tdb_delete(vfs_handle_struct *handle,
117                                 struct db_context *db,
118                                 SMB_STRUCT_STAT *psbuf)
119 {
120         NTSTATUS status;
121         struct file_id id = vfs_file_id_from_sbuf(handle->conn, psbuf);
122         struct db_record *rec = acl_tdb_lock(talloc_tos(), db, &id);
123
124         /*
125          * If rec == NULL there's not much we can do about it
126          */
127
128         if (rec == NULL) {
129                 DEBUG(10,("acl_tdb_delete: rec == NULL\n"));
130                 TALLOC_FREE(rec);
131                 return NT_STATUS_OK;
132         }
133
134         status = dbwrap_record_delete(rec);
135         TALLOC_FREE(rec);
136         return status;
137 }
138
139 /*******************************************************************
140  Pull a security descriptor into a DATA_BLOB from a tdb store.
141 *******************************************************************/
142
143 static NTSTATUS get_acl_blob(TALLOC_CTX *ctx,
144                         vfs_handle_struct *handle,
145                         files_struct *fsp,
146                         const struct smb_filename *smb_fname,
147                         DATA_BLOB *pblob)
148 {
149         uint8_t id_buf[16];
150         TDB_DATA data;
151         struct file_id id;
152         struct db_context *db = acl_db;
153         NTSTATUS status = NT_STATUS_OK;
154         SMB_STRUCT_STAT sbuf;
155
156         ZERO_STRUCT(sbuf);
157
158         if (fsp) {
159                 status = vfs_stat_fsp(fsp);
160                 sbuf = fsp->fsp_name->st;
161         } else {
162                 int ret = vfs_stat_smb_basename(handle->conn,
163                                 smb_fname->base_name,
164                                 &sbuf);
165                 if (ret == -1) {
166                         status = map_nt_error_from_unix(errno);
167                 }
168         }
169
170         if (!NT_STATUS_IS_OK(status)) {
171                 return status;
172         }
173
174         id = vfs_file_id_from_sbuf(handle->conn, &sbuf);
175
176         /* For backwards compatibility only store the dev/inode. */
177         push_file_id_16((char *)id_buf, &id);
178
179         status = dbwrap_fetch(db,
180                               ctx,
181                               make_tdb_data(id_buf, sizeof(id_buf)),
182                               &data);
183         if (!NT_STATUS_IS_OK(status)) {
184                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
185         }
186
187         pblob->data = data.dptr;
188         pblob->length = data.dsize;
189
190         DEBUG(10,("get_acl_blob: returned %u bytes from file %s\n",
191                 (unsigned int)data.dsize, smb_fname->base_name ));
192
193         if (pblob->length == 0 || pblob->data == NULL) {
194                 return NT_STATUS_NOT_FOUND;
195         }
196         return NT_STATUS_OK;
197 }
198
199 /*******************************************************************
200  Store a DATA_BLOB into a tdb record given an fsp pointer.
201 *******************************************************************/
202
203 static NTSTATUS store_acl_blob_fsp(vfs_handle_struct *handle,
204                                 files_struct *fsp,
205                                 DATA_BLOB *pblob)
206 {
207         uint8_t id_buf[16];
208         struct file_id id;
209         TDB_DATA data;
210         struct db_context *db = acl_db;
211         struct db_record *rec;
212         NTSTATUS status;
213
214         DEBUG(10,("store_acl_blob_fsp: storing blob length %u on file %s\n",
215                   (unsigned int)pblob->length, fsp_str_dbg(fsp)));
216
217         status = vfs_stat_fsp(fsp);
218         if (!NT_STATUS_IS_OK(status)) {
219                 return status;
220         }
221
222         id = vfs_file_id_from_sbuf(handle->conn, &fsp->fsp_name->st);
223
224         /* For backwards compatibility only store the dev/inode. */
225         push_file_id_16((char *)id_buf, &id);
226         rec = dbwrap_fetch_locked(db, talloc_tos(),
227                                   make_tdb_data(id_buf,
228                                                 sizeof(id_buf)));
229         if (rec == NULL) {
230                 DEBUG(0, ("store_acl_blob_fsp_tdb: fetch_lock failed\n"));
231                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
232         }
233         data.dptr = pblob->data;
234         data.dsize = pblob->length;
235         return dbwrap_record_store(rec, data, 0);
236 }
237
238 /*********************************************************************
239  On unlink we need to delete the tdb record (if using tdb).
240 *********************************************************************/
241
242 static int unlink_acl_tdb(vfs_handle_struct *handle,
243                           const struct smb_filename *smb_fname)
244 {
245         struct smb_filename *smb_fname_tmp = NULL;
246         struct db_context *db = acl_db;
247         int ret = -1;
248
249         smb_fname_tmp = cp_smb_filename(talloc_tos(), smb_fname);
250         if (smb_fname_tmp == NULL) {
251                 errno = ENOMEM;
252                 goto out;
253         }
254
255         if (smb_fname_tmp->flags & SMB_FILENAME_POSIX_PATH) {
256                 ret = SMB_VFS_LSTAT(handle->conn, smb_fname_tmp);
257         } else {
258                 ret = SMB_VFS_STAT(handle->conn, smb_fname_tmp);
259         }
260
261         if (ret == -1) {
262                 goto out;
263         }
264
265         ret = unlink_acl_common(handle, smb_fname_tmp);
266
267         if (ret == -1) {
268                 goto out;
269         }
270
271         acl_tdb_delete(handle, db, &smb_fname_tmp->st);
272  out:
273         return ret;
274 }
275
276 /*********************************************************************
277  On rmdir we need to delete the tdb record (if using tdb).
278 *********************************************************************/
279
280 static int rmdir_acl_tdb(vfs_handle_struct *handle,
281                 const struct smb_filename *smb_fname)
282 {
283
284         SMB_STRUCT_STAT sbuf;
285         struct db_context *db = acl_db;
286         int ret = -1;
287
288         ret = vfs_stat_smb_basename(handle->conn, smb_fname->base_name, &sbuf);
289         if (ret == -1) {
290                 return -1;
291         }
292
293         ret = rmdir_acl_common(handle, smb_fname);
294         if (ret == -1) {
295                 return -1;
296         }
297
298         acl_tdb_delete(handle, db, &sbuf);
299         return 0;
300 }
301
302 /*******************************************************************
303  Handle opening the storage tdb if so configured.
304 *******************************************************************/
305
306 static int connect_acl_tdb(struct vfs_handle_struct *handle,
307                                 const char *service,
308                                 const char *user)
309 {
310         int ret = SMB_VFS_NEXT_CONNECT(handle, service, user);
311
312         if (ret < 0) {
313                 return ret;
314         }
315
316         if (!acl_tdb_init()) {
317                 SMB_VFS_NEXT_DISCONNECT(handle);
318                 return -1;
319         }
320
321         /* Ensure we have the parameters correct if we're
322          * using this module. */
323         DEBUG(2,("connect_acl_tdb: setting 'inherit acls = true' "
324                 "'dos filemode = true' and "
325                 "'force unknown acl user = true' for service %s\n",
326                 service ));
327
328         lp_do_parameter(SNUM(handle->conn), "inherit acls", "true");
329         lp_do_parameter(SNUM(handle->conn), "dos filemode", "true");
330         lp_do_parameter(SNUM(handle->conn), "force unknown acl user", "true");
331
332         return 0;
333 }
334
335 /*********************************************************************
336  Remove a Windows ACL - we're setting the underlying POSIX ACL.
337 *********************************************************************/
338
339 static int sys_acl_set_file_tdb(vfs_handle_struct *handle,
340                               const char *path,
341                               SMB_ACL_TYPE_T type,
342                               SMB_ACL_T theacl)
343 {
344         SMB_STRUCT_STAT sbuf;
345         struct db_context *db = acl_db;
346         int ret = -1;
347
348         ret = vfs_stat_smb_basename(handle->conn, path, &sbuf);
349         if (ret == -1) {
350                 return -1;
351         }
352
353         ret = SMB_VFS_NEXT_SYS_ACL_SET_FILE(handle,
354                                                 path,
355                                                 type,
356                                                 theacl);
357         if (ret == -1) {
358                 return -1;
359         }
360
361         acl_tdb_delete(handle, db, &sbuf);
362         return 0;
363 }
364
365 /*********************************************************************
366  Remove a Windows ACL - we're setting the underlying POSIX ACL.
367 *********************************************************************/
368
369 static int sys_acl_set_fd_tdb(vfs_handle_struct *handle,
370                             files_struct *fsp,
371                             SMB_ACL_T theacl)
372 {
373         struct db_context *db = acl_db;
374         NTSTATUS status;
375         int ret;
376
377         status = vfs_stat_fsp(fsp);
378         if (!NT_STATUS_IS_OK(status)) {
379                 return -1;
380         }
381
382         ret = SMB_VFS_NEXT_SYS_ACL_SET_FD(handle,
383                                                 fsp,
384                                                 theacl);
385         if (ret == -1) {
386                 return -1;
387         }
388
389         acl_tdb_delete(handle, db, &fsp->fsp_name->st);
390         return 0;
391 }
392
393 static struct vfs_fn_pointers vfs_acl_tdb_fns = {
394         .connect_fn = connect_acl_tdb,
395         .disconnect_fn = disconnect_acl_tdb,
396         .rmdir_fn = rmdir_acl_tdb,
397         .unlink_fn = unlink_acl_tdb,
398         .chmod_fn = chmod_acl_module_common,
399         .fchmod_fn = fchmod_acl_module_common,
400         .fget_nt_acl_fn = fget_nt_acl_common,
401         .get_nt_acl_fn = get_nt_acl_common,
402         .fset_nt_acl_fn = fset_nt_acl_common,
403         .chmod_acl_fn = chmod_acl_acl_module_common,
404         .fchmod_acl_fn = fchmod_acl_acl_module_common,
405         .sys_acl_set_file_fn = sys_acl_set_file_tdb,
406         .sys_acl_set_fd_fn = sys_acl_set_fd_tdb
407 };
408
409 static_decl_vfs;
410 NTSTATUS vfs_acl_tdb_init(void)
411 {
412         return smb_register_vfs(SMB_VFS_INTERFACE_VERSION, "acl_tdb",
413                                 &vfs_acl_tdb_fns);
414 }