1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 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/>.
27 #include <selinux/selinux.h>
28 #include <selinux/label.h>
29 #include <selinux/context.h>
33 #include "path-util.h"
34 #include "selinux-util.h"
37 DEFINE_TRIVIAL_CLEANUP_FUNC(security_context_t, freecon);
38 DEFINE_TRIVIAL_CLEANUP_FUNC(context_t, context_free);
40 #define _cleanup_security_context_free_ _cleanup_(freeconp)
41 #define _cleanup_context_free_ _cleanup_(context_freep)
43 static int cached_use = -1;
44 static struct selabel_handle *label_hnd = NULL;
46 #define log_enforcing(...) log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG, __VA_ARGS__)
49 bool mac_selinux_use(void) {
52 cached_use = is_selinux_enabled() > 0;
60 /// UNNEEDED by elogind
62 void mac_selinux_retest(void) {
69 int mac_selinux_init(const char *prefix) {
73 usec_t before_timestamp, after_timestamp;
74 struct mallinfo before_mallinfo, after_mallinfo;
76 if (!mac_selinux_use())
82 before_mallinfo = mallinfo();
83 before_timestamp = now(CLOCK_MONOTONIC);
86 struct selinux_opt options[] = {
87 { .type = SELABEL_OPT_SUBSET, .value = prefix },
90 label_hnd = selabel_open(SELABEL_CTX_FILE, options, ELEMENTSOF(options));
92 label_hnd = selabel_open(SELABEL_CTX_FILE, NULL, 0);
95 log_enforcing("Failed to initialize SELinux context: %m");
96 r = security_getenforce() == 1 ? -errno : 0;
98 char timespan[FORMAT_TIMESPAN_MAX];
101 after_timestamp = now(CLOCK_MONOTONIC);
102 after_mallinfo = mallinfo();
104 l = after_mallinfo.uordblks > before_mallinfo.uordblks ? after_mallinfo.uordblks - before_mallinfo.uordblks : 0;
106 log_debug("Successfully loaded SELinux database in %s, size on heap is %iK.",
107 format_timespan(timespan, sizeof(timespan), after_timestamp - before_timestamp, 0),
115 /// UNNEEDED by elogind
117 void mac_selinux_finish(void) {
123 selabel_close(label_hnd);
129 int mac_selinux_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
137 /* if mac_selinux_init() wasn't called before we are a NOOP */
141 r = lstat(path, &st);
143 _cleanup_security_context_free_ security_context_t fcon = NULL;
145 r = selabel_lookup_raw(label_hnd, &fcon, path, st.st_mode);
147 /* If there's no label to set, then exit without warning */
148 if (r < 0 && errno == ENOENT)
152 r = lsetfilecon(path, fcon);
154 /* If the FS doesn't support labels, then exit without warning */
155 if (r < 0 && errno == EOPNOTSUPP)
161 /* Ignore ENOENT in some cases */
162 if (ignore_enoent && errno == ENOENT)
165 if (ignore_erofs && errno == EROFS)
168 log_enforcing("Unable to fix SELinux security context of %s: %m", path);
169 if (security_getenforce() == 1)
177 /// UNNEDED by elogind
179 int mac_selinux_apply(const char *path, const char *label) {
185 if (!mac_selinux_use())
188 if (setfilecon(path, (security_context_t) label) < 0) {
189 log_enforcing("Failed to set SELinux security context %s on path %s: %m", label, path);
190 if (security_getenforce() == 1)
197 int mac_selinux_get_create_label_from_exe(const char *exe, char **label) {
201 _cleanup_security_context_free_ security_context_t mycon = NULL, fcon = NULL;
202 security_class_t sclass;
207 if (!mac_selinux_use())
210 r = getcon_raw(&mycon);
214 r = getfilecon_raw(exe, &fcon);
218 sclass = string_to_security_class("process");
219 r = security_compute_create(mycon, fcon, sclass, (security_context_t *) label);
227 int mac_selinux_get_our_label(char **label) {
233 if (!mac_selinux_use())
236 r = getcon_raw(label);
244 int mac_selinux_get_child_mls_label(int socket_fd, const char *exe, const char *exec_label, char **label) {
248 _cleanup_security_context_free_ security_context_t mycon = NULL, peercon = NULL, fcon = NULL;
249 _cleanup_context_free_ context_t pcon = NULL, bcon = NULL;
250 security_class_t sclass;
251 const char *range = NULL;
253 assert(socket_fd >= 0);
257 if (!mac_selinux_use())
260 r = getcon_raw(&mycon);
264 r = getpeercon(socket_fd, &peercon);
269 /* If there is no context set for next exec let's use context
270 of target executable */
271 r = getfilecon_raw(exe, &fcon);
276 bcon = context_new(mycon);
280 pcon = context_new(peercon);
284 range = context_range_get(pcon);
288 r = context_range_set(bcon, range);
293 mycon = strdup(context_str(bcon));
297 sclass = string_to_security_class("process");
298 r = security_compute_create(mycon, fcon, sclass, (security_context_t *) label);
306 char* mac_selinux_free(char *label) {
312 if (!mac_selinux_use())
316 freecon((security_context_t) label);
323 int mac_selinux_create_file_prepare(const char *path, mode_t mode) {
327 _cleanup_security_context_free_ security_context_t filecon = NULL;
334 if (path_is_absolute(path))
335 r = selabel_lookup_raw(label_hnd, &filecon, path, mode);
337 _cleanup_free_ char *newpath;
339 newpath = path_make_absolute_cwd(path);
343 r = selabel_lookup_raw(label_hnd, &filecon, newpath, mode);
346 /* No context specified by the policy? Proceed without setting it. */
347 if (r < 0 && errno == ENOENT)
353 r = setfscreatecon(filecon);
355 log_enforcing("Failed to set SELinux security context %s for %s: %m", filecon, path);
360 if (r < 0 && security_getenforce() == 0)
367 void mac_selinux_create_file_clear(void) {
372 if (!mac_selinux_use())
375 setfscreatecon(NULL);
379 /// UNNEEDED by elogind
381 int mac_selinux_create_socket_prepare(const char *label) {
384 if (!mac_selinux_use())
389 if (setsockcreatecon((security_context_t) label) < 0) {
390 log_enforcing("Failed to set SELinux security context %s for sockets: %m", label);
392 if (security_getenforce() == 1)
400 void mac_selinux_create_socket_clear(void) {
405 if (!mac_selinux_use())
408 setsockcreatecon(NULL);
412 int mac_selinux_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
414 /* Binds a socket and label its file system object according to the SELinux policy */
417 _cleanup_security_context_free_ security_context_t fcon = NULL;
418 const struct sockaddr_un *un;
424 assert(addrlen >= sizeof(sa_family_t));
429 /* Filter out non-local sockets */
430 if (addr->sa_family != AF_UNIX)
433 /* Filter out anonymous sockets */
434 if (addrlen < sizeof(sa_family_t) + 1)
437 /* Filter out abstract namespace sockets */
438 un = (const struct sockaddr_un*) addr;
439 if (un->sun_path[0] == 0)
442 path = strndupa(un->sun_path, addrlen - offsetof(struct sockaddr_un, sun_path));
444 if (path_is_absolute(path))
445 r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK);
447 _cleanup_free_ char *newpath;
449 newpath = path_make_absolute_cwd(path);
453 r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK);
457 r = setfscreatecon(fcon);
459 if (r < 0 && errno != ENOENT) {
460 log_enforcing("Failed to set SELinux security context %s for %s: %m", fcon, path);
462 if (security_getenforce() == 1) {
468 r = bind(fd, addr, addrlen);
473 setfscreatecon(NULL);
478 return bind(fd, addr, addrlen) < 0 ? -errno : 0;