2 This file is part of systemd.
4 Copyright 2011 Lennart Poettering
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 #include "alloc-util.h"
25 #include "dirent-util.h"
28 #include "formats-util.h"
29 #include "logind-acl.h"
31 #include "string-util.h"
32 #include "udev-util.h"
35 static int flush_acl(acl_t acl) {
42 for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
44 found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
48 if (acl_get_tag_type(i, &tag) < 0)
54 if (acl_delete_entry(acl, i) < 0)
66 int devnode_acl(const char *path,
68 bool del, uid_t old_uid,
69 bool add, uid_t new_uid) {
77 acl = acl_get_file(path, ACL_TYPE_ACCESS);
89 } else if (del && old_uid > 0) {
92 r = acl_find_uid(acl, old_uid, &entry);
97 if (acl_delete_entry(acl, entry) < 0) {
106 if (add && new_uid > 0) {
108 acl_permset_t permset;
111 r = acl_find_uid(acl, new_uid, &entry);
116 if (acl_create_entry(&acl, &entry) < 0) {
121 if (acl_set_tag_type(entry, ACL_USER) < 0 ||
122 acl_set_qualifier(entry, &new_uid) < 0) {
128 if (acl_get_permset(entry, &permset) < 0) {
133 rd = acl_get_perm(permset, ACL_READ);
139 wt = acl_get_perm(permset, ACL_WRITE);
147 if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0) {
159 if (acl_calc_mask(&acl) < 0) {
164 if (acl_set_file(path, ACL_TYPE_ACCESS, acl) < 0) {
177 int devnode_acl_all(struct udev *udev,
180 bool del, uid_t old_uid,
181 bool add, uid_t new_uid) {
183 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
184 struct udev_list_entry *item = NULL, *first = NULL;
185 _cleanup_set_free_free_ Set *nodes = NULL;
186 _cleanup_closedir_ DIR *dir = NULL;
194 nodes = set_new(&string_hash_ops);
198 e = udev_enumerate_new(udev);
205 /* We can only match by one tag in libudev. We choose
206 * "uaccess" for that. If we could match for two tags here we
207 * could add the seat name as second match tag, but this would
208 * be hardly optimizable in libudev, and hence checking the
209 * second tag manually in our loop is a good solution. */
210 r = udev_enumerate_add_match_tag(e, "uaccess");
214 r = udev_enumerate_add_match_is_initialized(e);
218 r = udev_enumerate_scan_devices(e);
222 first = udev_enumerate_get_list_entry(e);
223 udev_list_entry_foreach(item, first) {
224 _cleanup_udev_device_unref_ struct udev_device *d = NULL;
225 const char *node, *sn;
227 d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
231 sn = udev_device_get_property_value(d, "ID_SEAT");
235 if (!streq(seat, sn))
238 node = udev_device_get_devnode(d);
239 /* In case people mistag devices with nodes, we need to ignore this */
247 log_debug("Found udev node %s for seat %s", n, seat);
248 r = set_consume(nodes, n);
253 /* udev exports "dead" device nodes to allow module on-demand loading,
254 * these devices are not known to the kernel at this moment */
255 dir = opendir("/run/udev/static_node-tags/uaccess");
257 FOREACH_DIRENT(dent, dir, return -errno) {
258 _cleanup_free_ char *unescaped_devname = NULL;
260 if (cunescape(dent->d_name, UNESCAPE_RELAX, &unescaped_devname) < 0)
263 n = strappend("/dev/", unescaped_devname);
267 log_debug("Found static node %s for seat %s", n, seat);
268 r = set_consume(nodes, n);
277 SET_FOREACH(n, nodes, i) {
280 log_debug("Changing ACLs at %s for seat %s (uid "UID_FMT"→"UID_FMT"%s%s)",
281 n, seat, old_uid, new_uid,
282 del ? " del" : "", add ? " add" : "");
284 k = devnode_acl(n, flush, del, old_uid, add, new_uid);
286 log_debug("Device %s disappeared while setting ACLs", n);
287 else if (k < 0 && r == 0)