1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-userdb-util.c Would be in dbus-userdb.c, but not used in libdbus
3 *
4 * Copyright (C) 2003, 2004, 2005 Red Hat, Inc.
5 *
6 * Licensed under the Academic Free License version 2.1
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 2 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, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23 #include <config.h>
24 #define DBUS_USERDB_INCLUDES_PRIVATE 1
25 #include "dbus-userdb.h"
26 #include "dbus-test.h"
27 #include "dbus-internals.h"
28 #include "dbus-protocol.h"
29 #include <string.h>
30
31 /**
32 * @addtogroup DBusInternalsUtils
33 * @{
34 */
35
36 /**
37 * Checks to see if the UID sent in is the console user
38 *
39 * @param uid UID of person to check
40 * @param error return location for errors
41 * @returns #TRUE if the UID is the same as the console user and there are no errors
42 */
43 dbus_bool_t
_dbus_is_console_user(dbus_uid_t uid,DBusError * error)44 _dbus_is_console_user (dbus_uid_t uid,
45 DBusError *error)
46 {
47
48 DBusUserDatabase *db;
49 const DBusUserInfo *info;
50 dbus_bool_t result = FALSE;
51
52 #ifdef HAVE_CONSOLE_OWNER_FILE
53
54 DBusString f;
55 DBusStat st;
56
57 if (!_dbus_string_init (&f))
58 {
59 _DBUS_SET_OOM (error);
60 return FALSE;
61 }
62
63 if (!_dbus_string_append(&f, DBUS_CONSOLE_OWNER_FILE))
64 {
65 _dbus_string_free(&f);
66 _DBUS_SET_OOM (error);
67 return FALSE;
68 }
69
70 if (_dbus_stat(&f, &st, NULL) && (st.uid == uid))
71 {
72 _dbus_string_free(&f);
73 return TRUE;
74 }
75
76 _dbus_string_free(&f);
77
78 #endif /* HAVE_CONSOLE_OWNER_FILE */
79
80 _dbus_user_database_lock_system ();
81
82 db = _dbus_user_database_get_system ();
83 if (db == NULL)
84 {
85 dbus_set_error (error, DBUS_ERROR_FAILED, "Could not get system database.");
86 _dbus_user_database_unlock_system ();
87 return FALSE;
88 }
89
90 /* TPTD: this should be cache-safe, we've locked the DB and
91 _dbus_user_at_console doesn't pass it on. */
92 info = _dbus_user_database_lookup (db, uid, NULL, error);
93
94 if (info == NULL)
95 {
96 _dbus_user_database_unlock_system ();
97 return FALSE;
98 }
99
100 result = _dbus_user_at_console (info->username, error);
101
102 _dbus_user_database_unlock_system ();
103
104 return result;
105 }
106
107 /**
108 * Gets user ID given username
109 *
110 * @param username the username
111 * @param uid return location for UID
112 * @returns #TRUE if username existed and we got the UID
113 */
114 dbus_bool_t
_dbus_get_user_id(const DBusString * username,dbus_uid_t * uid)115 _dbus_get_user_id (const DBusString *username,
116 dbus_uid_t *uid)
117 {
118 return _dbus_get_user_id_and_primary_group (username, uid, NULL);
119 }
120
121 /**
122 * Gets group ID given groupname
123 *
124 * @param groupname the groupname
125 * @param gid return location for GID
126 * @returns #TRUE if group name existed and we got the GID
127 */
128 dbus_bool_t
_dbus_get_group_id(const DBusString * groupname,dbus_gid_t * gid)129 _dbus_get_group_id (const DBusString *groupname,
130 dbus_gid_t *gid)
131 {
132 DBusUserDatabase *db;
133 const DBusGroupInfo *info;
134 _dbus_user_database_lock_system ();
135
136 db = _dbus_user_database_get_system ();
137 if (db == NULL)
138 {
139 _dbus_user_database_unlock_system ();
140 return FALSE;
141 }
142
143 if (!_dbus_user_database_get_groupname (db, groupname,
144 &info, NULL))
145 {
146 _dbus_user_database_unlock_system ();
147 return FALSE;
148 }
149
150 *gid = info->gid;
151
152 _dbus_user_database_unlock_system ();
153 return TRUE;
154 }
155
156 /**
157 * Gets user ID and primary group given username
158 *
159 * @param username the username
160 * @param uid_p return location for UID
161 * @param gid_p return location for GID
162 * @returns #TRUE if username existed and we got the UID and GID
163 */
164 dbus_bool_t
_dbus_get_user_id_and_primary_group(const DBusString * username,dbus_uid_t * uid_p,dbus_gid_t * gid_p)165 _dbus_get_user_id_and_primary_group (const DBusString *username,
166 dbus_uid_t *uid_p,
167 dbus_gid_t *gid_p)
168 {
169 DBusUserDatabase *db;
170 const DBusUserInfo *info;
171 _dbus_user_database_lock_system ();
172
173 db = _dbus_user_database_get_system ();
174 if (db == NULL)
175 {
176 _dbus_user_database_unlock_system ();
177 return FALSE;
178 }
179
180 if (!_dbus_user_database_get_username (db, username,
181 &info, NULL))
182 {
183 _dbus_user_database_unlock_system ();
184 return FALSE;
185 }
186
187 if (uid_p)
188 *uid_p = info->uid;
189 if (gid_p)
190 *gid_p = info->primary_gid;
191
192 _dbus_user_database_unlock_system ();
193 return TRUE;
194 }
195
196 /**
197 * Looks up a gid or group name in the user database. Only one of
198 * name or GID can be provided. There are wrapper functions for this
199 * that are better to use, this one does no locking or anything on the
200 * database and otherwise sort of sucks.
201 *
202 * @param db the database
203 * @param gid the group ID or #DBUS_GID_UNSET
204 * @param groupname group name or #NULL
205 * @param error error to fill in
206 * @returns the entry in the database
207 */
208 DBusGroupInfo*
_dbus_user_database_lookup_group(DBusUserDatabase * db,dbus_gid_t gid,const DBusString * groupname,DBusError * error)209 _dbus_user_database_lookup_group (DBusUserDatabase *db,
210 dbus_gid_t gid,
211 const DBusString *groupname,
212 DBusError *error)
213 {
214 DBusGroupInfo *info;
215
216 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
217
218 /* See if the group is really a number */
219 if (gid == DBUS_UID_UNSET)
220 {
221 unsigned long n;
222
223 if (_dbus_is_a_number (groupname, &n))
224 gid = n;
225 }
226
227 #ifdef DBUS_ENABLE_USERDB_CACHE
228 if (gid != DBUS_GID_UNSET)
229 info = _dbus_hash_table_lookup_uintptr (db->groups, gid);
230 else
231 info = _dbus_hash_table_lookup_string (db->groups_by_name,
232 _dbus_string_get_const_data (groupname));
233 if (info)
234 {
235 _dbus_verbose ("Using cache for GID "DBUS_GID_FORMAT" information\n",
236 info->gid);
237 return info;
238 }
239 else
240 #else
241 if (1)
242 #endif
243 {
244 if (gid != DBUS_GID_UNSET)
245 _dbus_verbose ("No cache for GID "DBUS_GID_FORMAT"\n",
246 gid);
247 else
248 _dbus_verbose ("No cache for groupname \"%s\"\n",
249 _dbus_string_get_const_data (groupname));
250
251 info = dbus_new0 (DBusGroupInfo, 1);
252 if (info == NULL)
253 {
254 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
255 return NULL;
256 }
257
258 if (gid != DBUS_GID_UNSET)
259 {
260 if (!_dbus_group_info_fill_gid (info, gid, error))
261 {
262 _DBUS_ASSERT_ERROR_IS_SET (error);
263 _dbus_group_info_free_allocated (info);
264 return NULL;
265 }
266 }
267 else
268 {
269 if (!_dbus_group_info_fill (info, groupname, error))
270 {
271 _DBUS_ASSERT_ERROR_IS_SET (error);
272 _dbus_group_info_free_allocated (info);
273 return NULL;
274 }
275 }
276
277 /* don't use these past here */
278 gid = DBUS_GID_UNSET;
279 groupname = NULL;
280
281 if (!_dbus_hash_table_insert_uintptr (db->groups, info->gid, info))
282 {
283 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
284 _dbus_group_info_free_allocated (info);
285 return NULL;
286 }
287
288
289 if (!_dbus_hash_table_insert_string (db->groups_by_name,
290 info->groupname,
291 info))
292 {
293 _dbus_hash_table_remove_uintptr (db->groups, info->gid);
294 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
295 return NULL;
296 }
297
298 return info;
299 }
300 }
301
302
303 /**
304 * Gets the user information for the given group name,
305 * returned group info should not be freed.
306 *
307 * @param db user database
308 * @param groupname the group name
309 * @param info return location for const ref to group info
310 * @param error error location
311 * @returns #FALSE if error is set
312 */
313 dbus_bool_t
_dbus_user_database_get_groupname(DBusUserDatabase * db,const DBusString * groupname,const DBusGroupInfo ** info,DBusError * error)314 _dbus_user_database_get_groupname (DBusUserDatabase *db,
315 const DBusString *groupname,
316 const DBusGroupInfo **info,
317 DBusError *error)
318 {
319 *info = _dbus_user_database_lookup_group (db, DBUS_GID_UNSET, groupname, error);
320 return *info != NULL;
321 }
322
323 /**
324 * Gets the user information for the given GID,
325 * returned group info should not be freed.
326 *
327 * @param db user database
328 * @param gid the group ID
329 * @param info return location for const ref to group info
330 * @param error error location
331 * @returns #FALSE if error is set
332 */
333 dbus_bool_t
_dbus_user_database_get_gid(DBusUserDatabase * db,dbus_gid_t gid,const DBusGroupInfo ** info,DBusError * error)334 _dbus_user_database_get_gid (DBusUserDatabase *db,
335 dbus_gid_t gid,
336 const DBusGroupInfo **info,
337 DBusError *error)
338 {
339 *info = _dbus_user_database_lookup_group (db, gid, NULL, error);
340 return *info != NULL;
341 }
342
343
344 /**
345 * Gets all groups corresponding to the given UID. Returns #FALSE
346 * if no memory, or user isn't known, but always initializes
347 * group_ids to a NULL array.
348 *
349 * @param uid the UID
350 * @param group_ids return location for array of group IDs
351 * @param n_group_ids return location for length of returned array
352 * @returns #TRUE if the UID existed and we got some credentials
353 */
354 dbus_bool_t
_dbus_groups_from_uid(dbus_uid_t uid,dbus_gid_t ** group_ids,int * n_group_ids)355 _dbus_groups_from_uid (dbus_uid_t uid,
356 dbus_gid_t **group_ids,
357 int *n_group_ids)
358 {
359 DBusUserDatabase *db;
360 const DBusUserInfo *info;
361 *group_ids = NULL;
362 *n_group_ids = 0;
363
364 _dbus_user_database_lock_system ();
365
366 db = _dbus_user_database_get_system ();
367 if (db == NULL)
368 {
369 _dbus_user_database_unlock_system ();
370 return FALSE;
371 }
372
373 if (!_dbus_user_database_get_uid (db, uid,
374 &info, NULL))
375 {
376 _dbus_user_database_unlock_system ();
377 return FALSE;
378 }
379
380 _dbus_assert (info->uid == uid);
381
382 if (info->n_group_ids > 0)
383 {
384 *group_ids = dbus_new (dbus_gid_t, info->n_group_ids);
385 if (*group_ids == NULL)
386 {
387 _dbus_user_database_unlock_system ();
388 return FALSE;
389 }
390
391 *n_group_ids = info->n_group_ids;
392
393 memcpy (*group_ids, info->group_ids, info->n_group_ids * sizeof (dbus_gid_t));
394 }
395
396 _dbus_user_database_unlock_system ();
397 return TRUE;
398 }
399 /** @} */
400
401 #ifdef DBUS_BUILD_TESTS
402 #include <stdio.h>
403
404 /**
405 * Unit test for dbus-userdb.c.
406 *
407 * @returns #TRUE on success.
408 */
409 dbus_bool_t
_dbus_userdb_test(const char * test_data_dir)410 _dbus_userdb_test (const char *test_data_dir)
411 {
412 const DBusString *username;
413 const DBusString *homedir;
414 dbus_uid_t uid;
415 unsigned long *group_ids;
416 int n_group_ids, i;
417
418 if (!_dbus_username_from_current_process (&username))
419 _dbus_assert_not_reached ("didn't get username");
420
421 if (!_dbus_homedir_from_current_process (&homedir))
422 _dbus_assert_not_reached ("didn't get homedir");
423
424 if (!_dbus_get_user_id (username, &uid))
425 _dbus_assert_not_reached ("didn't get uid");
426
427 if (!_dbus_groups_from_uid (uid, &group_ids, &n_group_ids))
428 _dbus_assert_not_reached ("didn't get groups");
429
430 printf (" Current user: %s homedir: %s gids:",
431 _dbus_string_get_const_data (username),
432 _dbus_string_get_const_data (homedir));
433
434 for (i=0; i<n_group_ids; i++)
435 printf(" %ld", group_ids[i]);
436
437 printf ("\n");
438
439 dbus_free (group_ids);
440
441 return TRUE;
442 }
443 #endif /* DBUS_BUILD_TESTS */
444