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;
47 bool mac_selinux_use(void) {
50 cached_use = is_selinux_enabled() > 0;
58 void mac_selinux_retest(void) {
64 int mac_selinux_init(const char *prefix) {
68 usec_t before_timestamp, after_timestamp;
69 struct mallinfo before_mallinfo, after_mallinfo;
71 if (!mac_selinux_use())
77 before_mallinfo = mallinfo();
78 before_timestamp = now(CLOCK_MONOTONIC);
81 struct selinux_opt options[] = {
82 { .type = SELABEL_OPT_SUBSET, .value = prefix },
85 label_hnd = selabel_open(SELABEL_CTX_FILE, options, ELEMENTSOF(options));
87 label_hnd = selabel_open(SELABEL_CTX_FILE, NULL, 0);
90 log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
91 "Failed to initialize SELinux context: %m");
92 r = security_getenforce() == 1 ? -errno : 0;
94 char timespan[FORMAT_TIMESPAN_MAX];
97 after_timestamp = now(CLOCK_MONOTONIC);
98 after_mallinfo = mallinfo();
100 l = after_mallinfo.uordblks > before_mallinfo.uordblks ? after_mallinfo.uordblks - before_mallinfo.uordblks : 0;
102 log_debug("Successfully loaded SELinux database in %s, size on heap is %iK.",
103 format_timespan(timespan, sizeof(timespan), after_timestamp - before_timestamp, 0),
111 int mac_selinux_fix(const char *path, bool ignore_enoent, bool ignore_erofs) {
116 security_context_t fcon;
121 r = lstat(path, &st);
123 r = selabel_lookup_raw(label_hnd, &fcon, path, st.st_mode);
125 /* If there's no label to set, then exit without warning */
126 if (r < 0 && errno == ENOENT)
130 r = lsetfilecon(path, fcon);
133 /* If the FS doesn't support labels, then exit without warning */
134 if (r < 0 && errno == ENOTSUP)
140 /* Ignore ENOENT in some cases */
141 if (ignore_enoent && errno == ENOENT)
144 if (ignore_erofs && errno == EROFS)
147 log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
148 "Unable to fix label of %s: %m", path);
149 r = security_getenforce() == 1 ? -errno : 0;
156 void mac_selinux_finish(void) {
159 if (!mac_selinux_use())
163 selabel_close(label_hnd);
167 int mac_selinux_get_create_label_from_exe(const char *exe, char **label) {
172 security_context_t mycon = NULL, fcon = NULL;
173 security_class_t sclass;
175 if (!mac_selinux_use()) {
184 r = getfilecon(exe, &fcon);
188 sclass = string_to_security_class("process");
189 r = security_compute_create(mycon, fcon, sclass, (security_context_t *) label);
191 log_debug("SELinux Socket context for %s will be set to %s", exe, *label);
194 if (r < 0 && security_getenforce() == 1)
204 int mac_selinux_get_our_label(char **label) {
220 int mac_selinux_get_child_mls_label(int socket_fd, const char *exe, char **label) {
225 _cleanup_security_context_free_ security_context_t mycon = NULL, peercon = NULL, fcon = NULL, ret = NULL;
226 _cleanup_context_free_ context_t pcon = NULL, bcon = NULL;
227 security_class_t sclass;
229 const char *range = NULL;
231 assert(socket_fd >= 0);
241 r = getpeercon(socket_fd, &peercon);
247 r = getexeccon(&fcon);
254 /* If there is no context set for next exec let's use context
255 of target executable */
256 r = getfilecon(exe, &fcon);
263 bcon = context_new(mycon);
269 pcon = context_new(peercon);
275 range = context_range_get(pcon);
281 r = context_range_set(bcon, range);
288 mycon = strdup(context_str(bcon));
294 sclass = string_to_security_class("process");
295 r = security_compute_create(mycon, fcon, sclass, &ret);
306 if (r < 0 && security_getenforce() == 1)
312 int mac_selinux_context_set(const char *path, mode_t mode) {
316 security_context_t filecon = NULL;
318 if (!mac_selinux_use() || !label_hnd)
321 r = selabel_lookup_raw(label_hnd, &filecon, path, mode);
322 if (r < 0 && errno != ENOENT)
325 r = setfscreatecon(filecon);
327 log_error("Failed to set SELinux file context on %s: %m", path);
334 if (r < 0 && security_getenforce() == 0)
341 int mac_selinux_socket_set(const char *label) {
344 if (!mac_selinux_use())
347 if (setsockcreatecon((security_context_t) label) < 0) {
348 log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG,
349 "Failed to set SELinux context (%s) on socket: %m", label);
351 if (security_getenforce() == 1)
359 void mac_selinux_context_clear(void) {
364 if (!mac_selinux_use())
367 setfscreatecon(NULL);
371 void mac_selinux_socket_clear(void) {
376 if (!mac_selinux_use())
379 setsockcreatecon(NULL);
383 void mac_selinux_free(const char *label) {
386 if (!mac_selinux_use())
389 freecon((security_context_t) label);
393 int mac_selinux_mkdir(const char *path, mode_t mode) {
397 /* Creates a directory and labels it according to the SELinux policy */
398 security_context_t fcon = NULL;
403 if (path_is_absolute(path))
404 r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFDIR);
406 _cleanup_free_ char *newpath;
408 newpath = path_make_absolute_cwd(path);
412 r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFDIR);
416 r = setfscreatecon(fcon);
418 if (r < 0 && errno != ENOENT) {
419 log_error("Failed to set security context %s for %s: %m", fcon, path);
421 if (security_getenforce() == 1) {
427 r = mkdir(path, mode);
432 setfscreatecon(NULL);
439 int mac_selinux_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) {
441 /* Binds a socket and label its file system object according to the SELinux policy */
444 security_context_t fcon = NULL;
445 const struct sockaddr_un *un;
451 assert(addrlen >= sizeof(sa_family_t));
453 if (!mac_selinux_use() || !label_hnd)
456 /* Filter out non-local sockets */
457 if (addr->sa_family != AF_UNIX)
460 /* Filter out anonymous sockets */
461 if (addrlen < sizeof(sa_family_t) + 1)
464 /* Filter out abstract namespace sockets */
465 un = (const struct sockaddr_un*) addr;
466 if (un->sun_path[0] == 0)
469 path = strndupa(un->sun_path, addrlen - offsetof(struct sockaddr_un, sun_path));
471 if (path_is_absolute(path))
472 r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK);
474 _cleanup_free_ char *newpath;
476 newpath = path_make_absolute_cwd(path);
480 r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK);
484 r = setfscreatecon(fcon);
486 if (r < 0 && errno != ENOENT) {
487 log_error("Failed to set security context %s for %s: %m", fcon, path);
489 if (security_getenforce() == 1) {
495 r = bind(fd, addr, addrlen);
500 setfscreatecon(NULL);
507 return bind(fd, addr, addrlen) < 0 ? -errno : 0;
510 int mac_selinux_apply(const char *path, const char *label) {
514 if (!mac_selinux_use())
517 r = setfilecon(path, (char *)label);