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 #if HAVE_SYSTEMD
32 #include <systemd/sd-daemon.h>
33 #include <systemd/sd-login.h>
34 #endif
35
36 /**
37 * @addtogroup DBusInternalsUtils
38 * @{
39 */
40
41 /**
42 * Checks to see if the UID sent in is the console user
43 *
44 * @param uid UID of person to check
45 * @param error return location for errors
46 * @returns #TRUE if the UID is the same as the console user and there are no errors
47 */
48 dbus_bool_t
_dbus_is_console_user(dbus_uid_t uid,DBusError * error)49 _dbus_is_console_user (dbus_uid_t uid,
50 DBusError *error)
51 {
52
53 DBusUserDatabase *db;
54 const DBusUserInfo *info;
55 dbus_bool_t result = FALSE;
56
57 #ifdef HAVE_SYSTEMD
58 if (sd_booted () > 0)
59 {
60 int r;
61
62 /* Check whether this user is logged in on at least one physical
63 seat */
64 r = sd_uid_get_seats (uid, 0, NULL);
65 if (r < 0)
66 {
67 dbus_set_error (error, _dbus_error_from_errno (-r),
68 "Failed to determine seats of user \"" DBUS_UID_FORMAT "\": %s",
69 uid,
70 _dbus_strerror (-r));
71 return FALSE;
72 }
73
74 return (r > 0);
75 }
76 #endif
77
78 #ifdef HAVE_CONSOLE_OWNER_FILE
79
80 DBusString f;
81 DBusStat st;
82
83 if (!_dbus_string_init (&f))
84 {
85 _DBUS_SET_OOM (error);
86 return FALSE;
87 }
88
89 if (!_dbus_string_append(&f, DBUS_CONSOLE_OWNER_FILE))
90 {
91 _dbus_string_free(&f);
92 _DBUS_SET_OOM (error);
93 return FALSE;
94 }
95
96 if (_dbus_stat(&f, &st, NULL) && (st.uid == uid))
97 {
98 _dbus_string_free(&f);
99 return TRUE;
100 }
101
102 _dbus_string_free(&f);
103
104 #endif /* HAVE_CONSOLE_OWNER_FILE */
105
106 _dbus_user_database_lock_system ();
107
108 db = _dbus_user_database_get_system ();
109 if (db == NULL)
110 {
111 dbus_set_error (error, DBUS_ERROR_FAILED, "Could not get system database.");
112 _dbus_user_database_unlock_system ();
113 return FALSE;
114 }
115
116 /* TPTD: this should be cache-safe, we've locked the DB and
117 _dbus_user_at_console doesn't pass it on. */
118 info = _dbus_user_database_lookup (db, uid, NULL, error);
119
120 if (info == NULL)
121 {
122 _dbus_user_database_unlock_system ();
123 return FALSE;
124 }
125
126 result = _dbus_user_at_console (info->username, error);
127
128 _dbus_user_database_unlock_system ();
129
130 return result;
131 }
132
133 /**
134 * Gets user ID given username
135 *
136 * @param username the username
137 * @param uid return location for UID
138 * @returns #TRUE if username existed and we got the UID
139 */
140 dbus_bool_t
_dbus_get_user_id(const DBusString * username,dbus_uid_t * uid)141 _dbus_get_user_id (const DBusString *username,
142 dbus_uid_t *uid)
143 {
144 return _dbus_get_user_id_and_primary_group (username, uid, NULL);
145 }
146
147 /**
148 * Gets group ID given groupname
149 *
150 * @param groupname the groupname
151 * @param gid return location for GID
152 * @returns #TRUE if group name existed and we got the GID
153 */
154 dbus_bool_t
_dbus_get_group_id(const DBusString * groupname,dbus_gid_t * gid)155 _dbus_get_group_id (const DBusString *groupname,
156 dbus_gid_t *gid)
157 {
158 DBusUserDatabase *db;
159 const DBusGroupInfo *info;
160 _dbus_user_database_lock_system ();
161
162 db = _dbus_user_database_get_system ();
163 if (db == NULL)
164 {
165 _dbus_user_database_unlock_system ();
166 return FALSE;
167 }
168
169 if (!_dbus_user_database_get_groupname (db, groupname,
170 &info, NULL))
171 {
172 _dbus_user_database_unlock_system ();
173 return FALSE;
174 }
175
176 *gid = info->gid;
177
178 _dbus_user_database_unlock_system ();
179 return TRUE;
180 }
181
182 /**
183 * Gets user ID and primary group given username
184 *
185 * @param username the username
186 * @param uid_p return location for UID
187 * @param gid_p return location for GID
188 * @returns #TRUE if username existed and we got the UID and GID
189 */
190 dbus_bool_t
_dbus_get_user_id_and_primary_group(const DBusString * username,dbus_uid_t * uid_p,dbus_gid_t * gid_p)191 _dbus_get_user_id_and_primary_group (const DBusString *username,
192 dbus_uid_t *uid_p,
193 dbus_gid_t *gid_p)
194 {
195 DBusUserDatabase *db;
196 const DBusUserInfo *info;
197 _dbus_user_database_lock_system ();
198
199 db = _dbus_user_database_get_system ();
200 if (db == NULL)
201 {
202 _dbus_user_database_unlock_system ();
203 return FALSE;
204 }
205
206 if (!_dbus_user_database_get_username (db, username,
207 &info, NULL))
208 {
209 _dbus_user_database_unlock_system ();
210 return FALSE;
211 }
212
213 if (uid_p)
214 *uid_p = info->uid;
215 if (gid_p)
216 *gid_p = info->primary_gid;
217
218 _dbus_user_database_unlock_system ();
219 return TRUE;
220 }
221
222 /**
223 * Looks up a gid or group name in the user database. Only one of
224 * name or GID can be provided. There are wrapper functions for this
225 * that are better to use, this one does no locking or anything on the
226 * database and otherwise sort of sucks.
227 *
228 * @param db the database
229 * @param gid the group ID or #DBUS_GID_UNSET
230 * @param groupname group name or #NULL
231 * @param error error to fill in
232 * @returns the entry in the database
233 */
234 DBusGroupInfo*
_dbus_user_database_lookup_group(DBusUserDatabase * db,dbus_gid_t gid,const DBusString * groupname,DBusError * error)235 _dbus_user_database_lookup_group (DBusUserDatabase *db,
236 dbus_gid_t gid,
237 const DBusString *groupname,
238 DBusError *error)
239 {
240 DBusGroupInfo *info;
241
242 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
243
244 /* See if the group is really a number */
245 if (gid == DBUS_UID_UNSET)
246 {
247 unsigned long n;
248
249 if (_dbus_is_a_number (groupname, &n))
250 gid = n;
251 }
252
253 #ifdef DBUS_ENABLE_USERDB_CACHE
254 if (gid != DBUS_GID_UNSET)
255 info = _dbus_hash_table_lookup_uintptr (db->groups, gid);
256 else
257 info = _dbus_hash_table_lookup_string (db->groups_by_name,
258 _dbus_string_get_const_data (groupname));
259 if (info)
260 {
261 _dbus_verbose ("Using cache for GID "DBUS_GID_FORMAT" information\n",
262 info->gid);
263 return info;
264 }
265 else
266 #else
267 if (1)
268 #endif
269 {
270 if (gid != DBUS_GID_UNSET)
271 _dbus_verbose ("No cache for GID "DBUS_GID_FORMAT"\n",
272 gid);
273 else
274 _dbus_verbose ("No cache for groupname \"%s\"\n",
275 _dbus_string_get_const_data (groupname));
276
277 info = dbus_new0 (DBusGroupInfo, 1);
278 if (info == NULL)
279 {
280 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
281 return NULL;
282 }
283
284 if (gid != DBUS_GID_UNSET)
285 {
286 if (!_dbus_group_info_fill_gid (info, gid, error))
287 {
288 _DBUS_ASSERT_ERROR_IS_SET (error);
289 _dbus_group_info_free_allocated (info);
290 return NULL;
291 }
292 }
293 else
294 {
295 if (!_dbus_group_info_fill (info, groupname, error))
296 {
297 _DBUS_ASSERT_ERROR_IS_SET (error);
298 _dbus_group_info_free_allocated (info);
299 return NULL;
300 }
301 }
302
303 /* don't use these past here */
304 gid = DBUS_GID_UNSET;
305 groupname = NULL;
306
307 if (!_dbus_hash_table_insert_uintptr (db->groups, info->gid, info))
308 {
309 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
310 _dbus_group_info_free_allocated (info);
311 return NULL;
312 }
313
314
315 if (!_dbus_hash_table_insert_string (db->groups_by_name,
316 info->groupname,
317 info))
318 {
319 _dbus_hash_table_remove_uintptr (db->groups, info->gid);
320 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
321 return NULL;
322 }
323
324 return info;
325 }
326 }
327
328
329 /**
330 * Gets the user information for the given group name,
331 * returned group info should not be freed.
332 *
333 * @param db user database
334 * @param groupname the group name
335 * @param info return location for const ref to group info
336 * @param error error location
337 * @returns #FALSE if error is set
338 */
339 dbus_bool_t
_dbus_user_database_get_groupname(DBusUserDatabase * db,const DBusString * groupname,const DBusGroupInfo ** info,DBusError * error)340 _dbus_user_database_get_groupname (DBusUserDatabase *db,
341 const DBusString *groupname,
342 const DBusGroupInfo **info,
343 DBusError *error)
344 {
345 *info = _dbus_user_database_lookup_group (db, DBUS_GID_UNSET, groupname, error);
346 return *info != NULL;
347 }
348
349 /**
350 * Gets the user information for the given GID,
351 * returned group info should not be freed.
352 *
353 * @param db user database
354 * @param gid the group ID
355 * @param info return location for const ref to group info
356 * @param error error location
357 * @returns #FALSE if error is set
358 */
359 dbus_bool_t
_dbus_user_database_get_gid(DBusUserDatabase * db,dbus_gid_t gid,const DBusGroupInfo ** info,DBusError * error)360 _dbus_user_database_get_gid (DBusUserDatabase *db,
361 dbus_gid_t gid,
362 const DBusGroupInfo **info,
363 DBusError *error)
364 {
365 *info = _dbus_user_database_lookup_group (db, gid, NULL, error);
366 return *info != NULL;
367 }
368
369
370 /**
371 * Gets all groups corresponding to the given UID. Returns #FALSE
372 * if no memory, or user isn't known, but always initializes
373 * group_ids to a NULL array.
374 *
375 * @param uid the UID
376 * @param group_ids return location for array of group IDs
377 * @param n_group_ids return location for length of returned array
378 * @returns #TRUE if the UID existed and we got some credentials
379 */
380 dbus_bool_t
_dbus_groups_from_uid(dbus_uid_t uid,dbus_gid_t ** group_ids,int * n_group_ids)381 _dbus_groups_from_uid (dbus_uid_t uid,
382 dbus_gid_t **group_ids,
383 int *n_group_ids)
384 {
385 DBusUserDatabase *db;
386 const DBusUserInfo *info;
387 *group_ids = NULL;
388 *n_group_ids = 0;
389
390 _dbus_user_database_lock_system ();
391
392 db = _dbus_user_database_get_system ();
393 if (db == NULL)
394 {
395 _dbus_user_database_unlock_system ();
396 return FALSE;
397 }
398
399 if (!_dbus_user_database_get_uid (db, uid,
400 &info, NULL))
401 {
402 _dbus_user_database_unlock_system ();
403 return FALSE;
404 }
405
406 _dbus_assert (info->uid == uid);
407
408 if (info->n_group_ids > 0)
409 {
410 *group_ids = dbus_new (dbus_gid_t, info->n_group_ids);
411 if (*group_ids == NULL)
412 {
413 _dbus_user_database_unlock_system ();
414 return FALSE;
415 }
416
417 *n_group_ids = info->n_group_ids;
418
419 memcpy (*group_ids, info->group_ids, info->n_group_ids * sizeof (dbus_gid_t));
420 }
421
422 _dbus_user_database_unlock_system ();
423 return TRUE;
424 }
425 /** @} */
426
427 #ifdef DBUS_BUILD_TESTS
428 #include <stdio.h>
429
430 /**
431 * Unit test for dbus-userdb.c.
432 *
433 * @returns #TRUE on success.
434 */
435 dbus_bool_t
_dbus_userdb_test(const char * test_data_dir)436 _dbus_userdb_test (const char *test_data_dir)
437 {
438 const DBusString *username;
439 const DBusString *homedir;
440 dbus_uid_t uid;
441 unsigned long *group_ids;
442 int n_group_ids, i;
443 DBusError error;
444
445 if (!_dbus_username_from_current_process (&username))
446 _dbus_assert_not_reached ("didn't get username");
447
448 if (!_dbus_homedir_from_current_process (&homedir))
449 _dbus_assert_not_reached ("didn't get homedir");
450
451 if (!_dbus_get_user_id (username, &uid))
452 _dbus_assert_not_reached ("didn't get uid");
453
454 if (!_dbus_groups_from_uid (uid, &group_ids, &n_group_ids))
455 _dbus_assert_not_reached ("didn't get groups");
456
457 printf (" Current user: %s homedir: %s gids:",
458 _dbus_string_get_const_data (username),
459 _dbus_string_get_const_data (homedir));
460
461 for (i=0; i<n_group_ids; i++)
462 printf(" %ld", group_ids[i]);
463
464 printf ("\n");
465
466 dbus_error_init (&error);
467 printf ("Is Console user: %i\n",
468 _dbus_is_console_user (uid, &error));
469 printf ("Invocation was OK: %s\n", error.message ? error.message : "yes");
470 dbus_error_free (&error);
471 printf ("Is Console user 4711: %i\n",
472 _dbus_is_console_user (4711, &error));
473 printf ("Invocation was OK: %s\n", error.message ? error.message : "yes");
474 dbus_error_free (&error);
475
476 dbus_free (group_ids);
477
478 return TRUE;
479 }
480 #endif /* DBUS_BUILD_TESTS */
481