1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2011 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
28 #include "logind-acl.h"
29 #include "udev-util.h"
31 static int flush_acl(acl_t acl) {
38 for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
40 found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
44 if (acl_get_tag_type(i, &tag) < 0)
50 if (acl_delete_entry(acl, i) < 0)
62 int devnode_acl(const char *path,
64 bool del, uid_t old_uid,
65 bool add, uid_t new_uid) {
73 acl = acl_get_file(path, ACL_TYPE_ACCESS);
85 } else if (del && old_uid > 0) {
88 r = acl_find_uid(acl, old_uid, &entry);
93 if (acl_delete_entry(acl, entry) < 0) {
102 if (add && new_uid > 0) {
104 acl_permset_t permset;
107 r = acl_find_uid(acl, new_uid, &entry);
112 if (acl_create_entry(&acl, &entry) < 0) {
117 if (acl_set_tag_type(entry, ACL_USER) < 0 ||
118 acl_set_qualifier(entry, &new_uid) < 0) {
124 if (acl_get_permset(entry, &permset) < 0) {
129 rd = acl_get_perm(permset, ACL_READ);
135 wt = acl_get_perm(permset, ACL_WRITE);
143 if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0) {
155 if (acl_calc_mask(&acl) < 0) {
160 if (acl_set_file(path, ACL_TYPE_ACCESS, acl) < 0) {
173 int devnode_acl_all(struct udev *udev,
176 bool del, uid_t old_uid,
177 bool add, uid_t new_uid) {
179 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
180 struct udev_list_entry *item = NULL, *first = NULL;
181 _cleanup_set_free_free_ Set *nodes = NULL;
182 _cleanup_closedir_ DIR *dir = NULL;
190 nodes = set_new(&string_hash_ops);
194 e = udev_enumerate_new(udev);
201 /* We can only match by one tag in libudev. We choose
202 * "uaccess" for that. If we could match for two tags here we
203 * could add the seat name as second match tag, but this would
204 * be hardly optimizable in libudev, and hence checking the
205 * second tag manually in our loop is a good solution. */
206 r = udev_enumerate_add_match_tag(e, "uaccess");
210 r = udev_enumerate_add_match_is_initialized(e);
214 r = udev_enumerate_scan_devices(e);
218 first = udev_enumerate_get_list_entry(e);
219 udev_list_entry_foreach(item, first) {
220 _cleanup_udev_device_unref_ struct udev_device *d = NULL;
221 const char *node, *sn;
223 d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
227 sn = udev_device_get_property_value(d, "ID_SEAT");
231 if (!streq(seat, sn))
234 node = udev_device_get_devnode(d);
235 /* In case people mistag devices with nodes, we need to ignore this */
243 log_debug("Found udev node %s for seat %s", n, seat);
244 r = set_consume(nodes, n);
249 /* udev exports "dead" device nodes to allow module on-demand loading,
250 * these devices are not known to the kernel at this moment */
251 dir = opendir("/run/udev/static_node-tags/uaccess");
253 FOREACH_DIRENT(dent, dir, return -errno) {
254 _cleanup_free_ char *unescaped_devname = NULL;
256 unescaped_devname = cunescape(dent->d_name);
257 if (!unescaped_devname)
260 n = strappend("/dev/", unescaped_devname);
264 log_debug("Found static node %s for seat %s", n, seat);
265 r = set_consume(nodes, n);
274 SET_FOREACH(n, nodes, i) {
277 log_debug("Changing ACLs at %s for seat %s (uid "UID_FMT"→"UID_FMT"%s%s)",
278 n, seat, old_uid, new_uid,
279 del ? " del" : "", add ? " add" : "");
281 k = devnode_acl(n, flush, del, old_uid, add, new_uid);
283 log_debug("Device %s disappeared while setting ACLs", n);
284 else if (k < 0 && r == 0)