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d6c9574f | 1 | /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
15ae422b LP |
2 | |
3 | /*** | |
4 | This file is part of systemd. | |
5 | ||
6 | Copyright 2010 Lennart Poettering | |
7 | ||
8 | systemd is free software; you can redistribute it and/or modify it | |
5430f7f2 LP |
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 | |
15ae422b LP |
11 | (at your option) any later version. |
12 | ||
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 | |
5430f7f2 | 16 | Lesser General Public License for more details. |
15ae422b | 17 | |
5430f7f2 | 18 | You should have received a copy of the GNU Lesser General Public License |
15ae422b LP |
19 | along with systemd; If not, see <http://www.gnu.org/licenses/>. |
20 | ***/ | |
21 | ||
22 | #include <errno.h> | |
07630cea | 23 | #include <sched.h> |
15ae422b | 24 | #include <stdio.h> |
07630cea LP |
25 | #include <string.h> |
26 | #include <sys/mount.h> | |
15ae422b | 27 | #include <sys/stat.h> |
07630cea | 28 | #include <unistd.h> |
25e870b5 | 29 | #include <linux/fs.h> |
15ae422b | 30 | |
7f112f50 | 31 | #include "dev-setup.h" |
3ffd4af2 | 32 | #include "fd-util.h" |
07630cea LP |
33 | #include "loopback-setup.h" |
34 | #include "missing.h" | |
35 | #include "mkdir.h" | |
3ffd4af2 | 36 | #include "namespace.h" |
07630cea | 37 | #include "path-util.h" |
d7b8eec7 | 38 | #include "selinux-util.h" |
2583fbea | 39 | #include "socket-util.h" |
07630cea LP |
40 | #include "string-util.h" |
41 | #include "strv.h" | |
42 | #include "util.h" | |
15ae422b | 43 | |
c17ec25e | 44 | typedef enum MountMode { |
15ae422b LP |
45 | /* This is ordered by priority! */ |
46 | INACCESSIBLE, | |
47 | READONLY, | |
ac0930c8 LP |
48 | PRIVATE_TMP, |
49 | PRIVATE_VAR_TMP, | |
7f112f50 | 50 | PRIVATE_DEV, |
a610cc4f | 51 | PRIVATE_BUS_ENDPOINT, |
15ae422b | 52 | READWRITE |
c17ec25e | 53 | } MountMode; |
15ae422b | 54 | |
c17ec25e | 55 | typedef struct BindMount { |
15ae422b | 56 | const char *path; |
c17ec25e | 57 | MountMode mode; |
ac0930c8 | 58 | bool done; |
ea92ae33 | 59 | bool ignore; |
c17ec25e | 60 | } BindMount; |
15ae422b | 61 | |
c17ec25e | 62 | static int append_mounts(BindMount **p, char **strv, MountMode mode) { |
15ae422b LP |
63 | char **i; |
64 | ||
613b411c LP |
65 | assert(p); |
66 | ||
15ae422b LP |
67 | STRV_FOREACH(i, strv) { |
68 | ||
ea92ae33 | 69 | (*p)->ignore = false; |
002b2268 | 70 | (*p)->done = false; |
ea92ae33 | 71 | |
94828d2d | 72 | if ((mode == INACCESSIBLE || mode == READONLY || mode == READWRITE) && (*i)[0] == '-') { |
ea92ae33 MW |
73 | (*p)->ignore = true; |
74 | (*i)++; | |
75 | } | |
76 | ||
15ae422b LP |
77 | if (!path_is_absolute(*i)) |
78 | return -EINVAL; | |
79 | ||
80 | (*p)->path = *i; | |
81 | (*p)->mode = mode; | |
82 | (*p)++; | |
83 | } | |
84 | ||
85 | return 0; | |
86 | } | |
87 | ||
c17ec25e MS |
88 | static int mount_path_compare(const void *a, const void *b) { |
89 | const BindMount *p = a, *q = b; | |
a0827e2b | 90 | int d; |
15ae422b | 91 | |
a0827e2b | 92 | d = path_compare(p->path, q->path); |
15ae422b | 93 | |
5a8af538 | 94 | if (d == 0) { |
15ae422b LP |
95 | /* If the paths are equal, check the mode */ |
96 | if (p->mode < q->mode) | |
97 | return -1; | |
98 | ||
99 | if (p->mode > q->mode) | |
100 | return 1; | |
101 | ||
102 | return 0; | |
103 | } | |
104 | ||
105 | /* If the paths are not equal, then order prefixes first */ | |
a0827e2b | 106 | return d; |
15ae422b LP |
107 | } |
108 | ||
c17ec25e MS |
109 | static void drop_duplicates(BindMount *m, unsigned *n) { |
110 | BindMount *f, *t, *previous; | |
15ae422b | 111 | |
c17ec25e | 112 | assert(m); |
15ae422b | 113 | assert(n); |
15ae422b | 114 | |
c17ec25e | 115 | for (f = m, t = m, previous = NULL; f < m+*n; f++) { |
15ae422b | 116 | |
ac0930c8 | 117 | /* The first one wins */ |
15ae422b LP |
118 | if (previous && path_equal(f->path, previous->path)) |
119 | continue; | |
120 | ||
e2d7c1a0 | 121 | *t = *f; |
15ae422b | 122 | |
15ae422b LP |
123 | previous = t; |
124 | ||
125 | t++; | |
126 | } | |
127 | ||
c17ec25e | 128 | *n = t - m; |
15ae422b LP |
129 | } |
130 | ||
7f112f50 LP |
131 | static int mount_dev(BindMount *m) { |
132 | static const char devnodes[] = | |
133 | "/dev/null\0" | |
134 | "/dev/zero\0" | |
135 | "/dev/full\0" | |
136 | "/dev/random\0" | |
137 | "/dev/urandom\0" | |
138 | "/dev/tty\0"; | |
139 | ||
2b85f4e1 | 140 | char temporary_mount[] = "/tmp/namespace-dev-XXXXXX"; |
63cc4c31 | 141 | const char *d, *dev = NULL, *devpts = NULL, *devshm = NULL, *devhugepages = NULL, *devmqueue = NULL, *devlog = NULL, *devptmx = NULL; |
7f112f50 LP |
142 | _cleanup_umask_ mode_t u; |
143 | int r; | |
144 | ||
145 | assert(m); | |
146 | ||
147 | u = umask(0000); | |
148 | ||
2b85f4e1 LP |
149 | if (!mkdtemp(temporary_mount)) |
150 | return -errno; | |
151 | ||
63c372cb | 152 | dev = strjoina(temporary_mount, "/dev"); |
dc751688 | 153 | (void) mkdir(dev, 0755); |
2b85f4e1 LP |
154 | if (mount("tmpfs", dev, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=755") < 0) { |
155 | r = -errno; | |
156 | goto fail; | |
157 | } | |
158 | ||
63c372cb | 159 | devpts = strjoina(temporary_mount, "/dev/pts"); |
dc751688 | 160 | (void) mkdir(devpts, 0755); |
2b85f4e1 LP |
161 | if (mount("/dev/pts", devpts, NULL, MS_BIND, NULL) < 0) { |
162 | r = -errno; | |
163 | goto fail; | |
164 | } | |
165 | ||
63c372cb | 166 | devptmx = strjoina(temporary_mount, "/dev/ptmx"); |
3164e3cb ZJS |
167 | if (symlink("pts/ptmx", devptmx) < 0) { |
168 | r = -errno; | |
169 | goto fail; | |
170 | } | |
e06b6479 | 171 | |
63c372cb | 172 | devshm = strjoina(temporary_mount, "/dev/shm"); |
dc751688 | 173 | (void) mkdir(devshm, 01777); |
2b85f4e1 LP |
174 | r = mount("/dev/shm", devshm, NULL, MS_BIND, NULL); |
175 | if (r < 0) { | |
176 | r = -errno; | |
177 | goto fail; | |
178 | } | |
179 | ||
63c372cb | 180 | devmqueue = strjoina(temporary_mount, "/dev/mqueue"); |
dc751688 | 181 | (void) mkdir(devmqueue, 0755); |
3164e3cb | 182 | (void) mount("/dev/mqueue", devmqueue, NULL, MS_BIND, NULL); |
2b85f4e1 | 183 | |
63c372cb | 184 | devhugepages = strjoina(temporary_mount, "/dev/hugepages"); |
dc751688 | 185 | (void) mkdir(devhugepages, 0755); |
3164e3cb | 186 | (void) mount("/dev/hugepages", devhugepages, NULL, MS_BIND, NULL); |
2b85f4e1 | 187 | |
63c372cb | 188 | devlog = strjoina(temporary_mount, "/dev/log"); |
3164e3cb | 189 | (void) symlink("/run/systemd/journal/dev-log", devlog); |
82d25240 | 190 | |
7f112f50 | 191 | NULSTR_FOREACH(d, devnodes) { |
2b85f4e1 LP |
192 | _cleanup_free_ char *dn = NULL; |
193 | struct stat st; | |
194 | ||
195 | r = stat(d, &st); | |
7f112f50 | 196 | if (r < 0) { |
2b85f4e1 LP |
197 | |
198 | if (errno == ENOENT) | |
199 | continue; | |
200 | ||
201 | r = -errno; | |
202 | goto fail; | |
7f112f50 LP |
203 | } |
204 | ||
2b85f4e1 LP |
205 | if (!S_ISBLK(st.st_mode) && |
206 | !S_ISCHR(st.st_mode)) { | |
207 | r = -EINVAL; | |
208 | goto fail; | |
209 | } | |
210 | ||
211 | if (st.st_rdev == 0) | |
212 | continue; | |
213 | ||
214 | dn = strappend(temporary_mount, d); | |
215 | if (!dn) { | |
216 | r = -ENOMEM; | |
217 | goto fail; | |
218 | } | |
219 | ||
ecabcf8b | 220 | mac_selinux_create_file_prepare(d, st.st_mode); |
2b85f4e1 | 221 | r = mknod(dn, st.st_mode, st.st_rdev); |
ecabcf8b | 222 | mac_selinux_create_file_clear(); |
dd078a1e | 223 | |
2b85f4e1 LP |
224 | if (r < 0) { |
225 | r = -errno; | |
226 | goto fail; | |
227 | } | |
7f112f50 LP |
228 | } |
229 | ||
03cfe0d5 | 230 | dev_setup(temporary_mount, UID_INVALID, GID_INVALID); |
7f112f50 | 231 | |
ee818b89 AC |
232 | /* Create the /dev directory if missing. It is more likely to be |
233 | * missing when the service is started with RootDirectory. This is | |
234 | * consistent with mount units creating the mount points when missing. | |
235 | */ | |
236 | (void) mkdir_p_label(m->path, 0755); | |
237 | ||
238 | if (mount(dev, m->path, NULL, MS_MOVE, NULL) < 0) { | |
2b85f4e1 LP |
239 | r = -errno; |
240 | goto fail; | |
241 | } | |
7f112f50 | 242 | |
2b85f4e1 LP |
243 | rmdir(dev); |
244 | rmdir(temporary_mount); | |
7f112f50 | 245 | |
2b85f4e1 | 246 | return 0; |
7f112f50 | 247 | |
2b85f4e1 LP |
248 | fail: |
249 | if (devpts) | |
250 | umount(devpts); | |
7f112f50 | 251 | |
2b85f4e1 LP |
252 | if (devshm) |
253 | umount(devshm); | |
7f112f50 | 254 | |
2b85f4e1 LP |
255 | if (devhugepages) |
256 | umount(devhugepages); | |
7f112f50 | 257 | |
2b85f4e1 LP |
258 | if (devmqueue) |
259 | umount(devmqueue); | |
7f112f50 | 260 | |
d267c5aa ZJS |
261 | umount(dev); |
262 | rmdir(dev); | |
2b85f4e1 | 263 | rmdir(temporary_mount); |
7f112f50 | 264 | |
2b85f4e1 | 265 | return r; |
7f112f50 LP |
266 | } |
267 | ||
a610cc4f DM |
268 | static int mount_kdbus(BindMount *m) { |
269 | ||
270 | char temporary_mount[] = "/tmp/kdbus-dev-XXXXXX"; | |
271 | _cleanup_free_ char *basepath = NULL; | |
272 | _cleanup_umask_ mode_t u; | |
120d578e | 273 | char *busnode = NULL, *root; |
a610cc4f DM |
274 | struct stat st; |
275 | int r; | |
276 | ||
277 | assert(m); | |
278 | ||
279 | u = umask(0000); | |
280 | ||
4a62c710 MS |
281 | if (!mkdtemp(temporary_mount)) |
282 | return log_error_errno(errno, "Failed create temp dir: %m"); | |
a610cc4f | 283 | |
63c372cb | 284 | root = strjoina(temporary_mount, "/kdbus"); |
dc751688 | 285 | (void) mkdir(root, 0755); |
a610cc4f DM |
286 | if (mount("tmpfs", root, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=777") < 0) { |
287 | r = -errno; | |
288 | goto fail; | |
289 | } | |
290 | ||
291 | /* create a new /dev/null dev node copy so we have some fodder to | |
292 | * bind-mount the custom endpoint over. */ | |
293 | if (stat("/dev/null", &st) < 0) { | |
76ef789d | 294 | r = log_error_errno(errno, "Failed to stat /dev/null: %m"); |
a610cc4f DM |
295 | goto fail; |
296 | } | |
297 | ||
63c372cb | 298 | busnode = strjoina(root, "/bus"); |
a610cc4f | 299 | if (mknod(busnode, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0) { |
94c156cd LP |
300 | r = log_error_errno(errno, "mknod() for %s failed: %m", |
301 | busnode); | |
a610cc4f DM |
302 | goto fail; |
303 | } | |
304 | ||
4543768d | 305 | r = mount(m->path, busnode, NULL, MS_BIND, NULL); |
a610cc4f | 306 | if (r < 0) { |
94c156cd LP |
307 | r = log_error_errno(errno, "bind mount of %s failed: %m", |
308 | m->path); | |
a610cc4f DM |
309 | goto fail; |
310 | } | |
311 | ||
312 | basepath = dirname_malloc(m->path); | |
313 | if (!basepath) { | |
314 | r = -ENOMEM; | |
315 | goto fail; | |
316 | } | |
317 | ||
318 | if (mount(root, basepath, NULL, MS_MOVE, NULL) < 0) { | |
94c156cd LP |
319 | r = log_error_errno(errno, "bind mount of %s failed: %m", |
320 | basepath); | |
a610cc4f DM |
321 | goto fail; |
322 | } | |
323 | ||
324 | rmdir(temporary_mount); | |
325 | return 0; | |
326 | ||
327 | fail: | |
328 | if (busnode) { | |
329 | umount(busnode); | |
330 | unlink(busnode); | |
331 | } | |
332 | ||
1775f1eb ZJS |
333 | umount(root); |
334 | rmdir(root); | |
a610cc4f DM |
335 | rmdir(temporary_mount); |
336 | ||
337 | return r; | |
338 | } | |
339 | ||
ac0930c8 | 340 | static int apply_mount( |
c17ec25e | 341 | BindMount *m, |
ac0930c8 | 342 | const char *tmp_dir, |
c17ec25e | 343 | const char *var_tmp_dir) { |
ac0930c8 | 344 | |
15ae422b | 345 | const char *what; |
15ae422b | 346 | int r; |
15ae422b | 347 | |
c17ec25e | 348 | assert(m); |
15ae422b | 349 | |
c17ec25e | 350 | switch (m->mode) { |
15ae422b LP |
351 | |
352 | case INACCESSIBLE: | |
6d313367 LP |
353 | |
354 | /* First, get rid of everything that is below if there | |
355 | * is anything... Then, overmount it with an | |
356 | * inaccessible directory. */ | |
357 | umount_recursive(m->path, 0); | |
358 | ||
c17ec25e | 359 | what = "/run/systemd/inaccessible"; |
15ae422b LP |
360 | break; |
361 | ||
362 | case READONLY: | |
15ae422b | 363 | case READWRITE: |
d6797c92 LP |
364 | /* Nothing to mount here, we just later toggle the |
365 | * MS_RDONLY bit for the mount point */ | |
366 | return 0; | |
15ae422b | 367 | |
ac0930c8 LP |
368 | case PRIVATE_TMP: |
369 | what = tmp_dir; | |
370 | break; | |
371 | ||
372 | case PRIVATE_VAR_TMP: | |
373 | what = var_tmp_dir; | |
15ae422b | 374 | break; |
e364ad06 | 375 | |
d6797c92 LP |
376 | case PRIVATE_DEV: |
377 | return mount_dev(m); | |
378 | ||
a610cc4f DM |
379 | case PRIVATE_BUS_ENDPOINT: |
380 | return mount_kdbus(m); | |
381 | ||
e364ad06 LP |
382 | default: |
383 | assert_not_reached("Unknown mode"); | |
15ae422b LP |
384 | } |
385 | ||
ac0930c8 | 386 | assert(what); |
15ae422b | 387 | |
c17ec25e | 388 | r = mount(what, m->path, NULL, MS_BIND|MS_REC, NULL); |
ac0930c8 | 389 | if (r >= 0) |
c17ec25e | 390 | log_debug("Successfully mounted %s to %s", what, m->path); |
ea92ae33 | 391 | else if (m->ignore && errno == ENOENT) |
d6797c92 | 392 | return 0; |
15ae422b | 393 | |
ac0930c8 LP |
394 | return r; |
395 | } | |
15ae422b | 396 | |
c17ec25e | 397 | static int make_read_only(BindMount *m) { |
ac0930c8 | 398 | int r; |
15ae422b | 399 | |
c17ec25e | 400 | assert(m); |
ac0930c8 | 401 | |
d6797c92 LP |
402 | if (IN_SET(m->mode, INACCESSIBLE, READONLY)) |
403 | r = bind_remount_recursive(m->path, true); | |
664064d6 | 404 | else if (IN_SET(m->mode, READWRITE, PRIVATE_TMP, PRIVATE_VAR_TMP, PRIVATE_DEV)) |
d6797c92 LP |
405 | r = bind_remount_recursive(m->path, false); |
406 | else | |
407 | r = 0; | |
ac0930c8 | 408 | |
d6797c92 LP |
409 | if (m->ignore && r == -ENOENT) |
410 | return 0; | |
ac0930c8 | 411 | |
d6797c92 | 412 | return r; |
15ae422b LP |
413 | } |
414 | ||
613b411c | 415 | int setup_namespace( |
ee818b89 | 416 | const char* root_directory, |
613b411c LP |
417 | char** read_write_dirs, |
418 | char** read_only_dirs, | |
419 | char** inaccessible_dirs, | |
a004cb4c LP |
420 | const char* tmp_dir, |
421 | const char* var_tmp_dir, | |
422 | const char* bus_endpoint_path, | |
7f112f50 | 423 | bool private_dev, |
1b8689f9 LP |
424 | ProtectHome protect_home, |
425 | ProtectSystem protect_system, | |
e6547662 | 426 | unsigned long mount_flags) { |
15ae422b | 427 | |
7ff7394d | 428 | BindMount *m, *mounts = NULL; |
613b411c | 429 | unsigned n; |
c17ec25e | 430 | int r = 0; |
15ae422b | 431 | |
613b411c | 432 | if (mount_flags == 0) |
c17ec25e | 433 | mount_flags = MS_SHARED; |
ac0930c8 | 434 | |
d5a3f0ea ZJS |
435 | if (unshare(CLONE_NEWNS) < 0) |
436 | return -errno; | |
15ae422b | 437 | |
a610cc4f | 438 | n = !!tmp_dir + !!var_tmp_dir + !!bus_endpoint_path + |
613b411c LP |
439 | strv_length(read_write_dirs) + |
440 | strv_length(read_only_dirs) + | |
7f112f50 | 441 | strv_length(inaccessible_dirs) + |
417116f2 | 442 | private_dev + |
c8835999 | 443 | (protect_home != PROTECT_HOME_NO ? 3 : 0) + |
051be1f7 | 444 | (protect_system != PROTECT_SYSTEM_NO ? 2 : 0) + |
1b8689f9 | 445 | (protect_system == PROTECT_SYSTEM_FULL ? 1 : 0); |
613b411c LP |
446 | |
447 | if (n > 0) { | |
002b2268 | 448 | m = mounts = (BindMount *) alloca0(n * sizeof(BindMount)); |
613b411c LP |
449 | r = append_mounts(&m, read_write_dirs, READWRITE); |
450 | if (r < 0) | |
451 | return r; | |
452 | ||
453 | r = append_mounts(&m, read_only_dirs, READONLY); | |
454 | if (r < 0) | |
455 | return r; | |
456 | ||
457 | r = append_mounts(&m, inaccessible_dirs, INACCESSIBLE); | |
458 | if (r < 0) | |
7ff7394d ZJS |
459 | return r; |
460 | ||
613b411c | 461 | if (tmp_dir) { |
ee818b89 | 462 | m->path = prefix_roota(root_directory, "/tmp"); |
7ff7394d ZJS |
463 | m->mode = PRIVATE_TMP; |
464 | m++; | |
613b411c | 465 | } |
7ff7394d | 466 | |
613b411c | 467 | if (var_tmp_dir) { |
ee818b89 | 468 | m->path = prefix_roota(root_directory, "/var/tmp"); |
7ff7394d ZJS |
469 | m->mode = PRIVATE_VAR_TMP; |
470 | m++; | |
471 | } | |
ac0930c8 | 472 | |
7f112f50 | 473 | if (private_dev) { |
ee818b89 | 474 | m->path = prefix_roota(root_directory, "/dev"); |
7f112f50 LP |
475 | m->mode = PRIVATE_DEV; |
476 | m++; | |
477 | } | |
478 | ||
a610cc4f | 479 | if (bus_endpoint_path) { |
ee818b89 | 480 | m->path = prefix_roota(root_directory, bus_endpoint_path); |
a610cc4f DM |
481 | m->mode = PRIVATE_BUS_ENDPOINT; |
482 | m++; | |
483 | } | |
484 | ||
1b8689f9 | 485 | if (protect_home != PROTECT_HOME_NO) { |
ee818b89 AC |
486 | const char *home_dir, *run_user_dir, *root_dir; |
487 | ||
488 | home_dir = prefix_roota(root_directory, "/home"); | |
489 | home_dir = strjoina("-", home_dir); | |
490 | run_user_dir = prefix_roota(root_directory, "/run/user"); | |
491 | run_user_dir = strjoina("-", run_user_dir); | |
492 | root_dir = prefix_roota(root_directory, "/root"); | |
493 | root_dir = strjoina("-", root_dir); | |
494 | ||
495 | r = append_mounts(&m, STRV_MAKE(home_dir, run_user_dir, root_dir), | |
496 | protect_home == PROTECT_HOME_READ_ONLY ? READONLY : INACCESSIBLE); | |
417116f2 LP |
497 | if (r < 0) |
498 | return r; | |
499 | } | |
500 | ||
1b8689f9 | 501 | if (protect_system != PROTECT_SYSTEM_NO) { |
ee818b89 AC |
502 | const char *usr_dir, *boot_dir, *etc_dir; |
503 | ||
d38e01dc | 504 | usr_dir = prefix_roota(root_directory, "/usr"); |
ee818b89 AC |
505 | boot_dir = prefix_roota(root_directory, "/boot"); |
506 | boot_dir = strjoina("-", boot_dir); | |
507 | etc_dir = prefix_roota(root_directory, "/etc"); | |
508 | ||
509 | r = append_mounts(&m, protect_system == PROTECT_SYSTEM_FULL | |
510 | ? STRV_MAKE(usr_dir, boot_dir, etc_dir) | |
511 | : STRV_MAKE(usr_dir, boot_dir), READONLY); | |
417116f2 LP |
512 | if (r < 0) |
513 | return r; | |
514 | } | |
515 | ||
7ff7394d | 516 | assert(mounts + n == m); |
ac0930c8 | 517 | |
7ff7394d ZJS |
518 | qsort(mounts, n, sizeof(BindMount), mount_path_compare); |
519 | drop_duplicates(mounts, &n); | |
15ae422b LP |
520 | } |
521 | ||
ee818b89 | 522 | if (n > 0 || root_directory) { |
c2c13f2d LP |
523 | /* Remount / as SLAVE so that nothing now mounted in the namespace |
524 | shows up in the parent */ | |
525 | if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) | |
526 | return -errno; | |
ee818b89 AC |
527 | } |
528 | ||
529 | if (root_directory) { | |
530 | /* Turn directory into bind mount */ | |
531 | if (mount(root_directory, root_directory, NULL, MS_BIND|MS_REC, NULL) < 0) | |
532 | return -errno; | |
533 | } | |
c2c13f2d | 534 | |
ee818b89 | 535 | if (n > 0) { |
c2c13f2d LP |
536 | for (m = mounts; m < mounts + n; ++m) { |
537 | r = apply_mount(m, tmp_dir, var_tmp_dir); | |
538 | if (r < 0) | |
539 | goto fail; | |
540 | } | |
15ae422b | 541 | |
c2c13f2d LP |
542 | for (m = mounts; m < mounts + n; ++m) { |
543 | r = make_read_only(m); | |
544 | if (r < 0) | |
545 | goto fail; | |
546 | } | |
15ae422b LP |
547 | } |
548 | ||
ee818b89 AC |
549 | if (root_directory) { |
550 | /* MS_MOVE does not work on MS_SHARED so the remount MS_SHARED will be done later */ | |
551 | r = mount_move_root(root_directory); | |
552 | ||
553 | /* at this point, we cannot rollback */ | |
554 | if (r < 0) | |
555 | return r; | |
556 | } | |
557 | ||
c2c13f2d LP |
558 | /* Remount / as the desired mode. Not that this will not |
559 | * reestablish propagation from our side to the host, since | |
560 | * what's disconnected is disconnected. */ | |
1f6b4113 | 561 | if (mount(NULL, "/", NULL, mount_flags | MS_REC, NULL) < 0) |
ee818b89 AC |
562 | /* at this point, we cannot rollback */ |
563 | return -errno; | |
15ae422b | 564 | |
15ae422b LP |
565 | return 0; |
566 | ||
613b411c | 567 | fail: |
c2c13f2d LP |
568 | if (n > 0) { |
569 | for (m = mounts; m < mounts + n; ++m) | |
570 | if (m->done) | |
42b1b990 | 571 | (void) umount2(m->path, MNT_DETACH); |
c2c13f2d | 572 | } |
613b411c LP |
573 | |
574 | return r; | |
575 | } | |
576 | ||
577 | static int setup_one_tmp_dir(const char *id, const char *prefix, char **path) { | |
578 | _cleanup_free_ char *x = NULL; | |
6b46ea73 LP |
579 | char bid[SD_ID128_STRING_MAX]; |
580 | sd_id128_t boot_id; | |
581 | int r; | |
613b411c LP |
582 | |
583 | assert(id); | |
584 | assert(prefix); | |
585 | assert(path); | |
586 | ||
6b46ea73 LP |
587 | /* We include the boot id in the directory so that after a |
588 | * reboot we can easily identify obsolete directories. */ | |
589 | ||
590 | r = sd_id128_get_boot(&boot_id); | |
591 | if (r < 0) | |
592 | return r; | |
593 | ||
594 | x = strjoin(prefix, "/systemd-private-", sd_id128_to_string(boot_id, bid), "-", id, "-XXXXXX", NULL); | |
613b411c LP |
595 | if (!x) |
596 | return -ENOMEM; | |
597 | ||
598 | RUN_WITH_UMASK(0077) | |
599 | if (!mkdtemp(x)) | |
600 | return -errno; | |
601 | ||
602 | RUN_WITH_UMASK(0000) { | |
603 | char *y; | |
604 | ||
63c372cb | 605 | y = strjoina(x, "/tmp"); |
613b411c LP |
606 | |
607 | if (mkdir(y, 0777 | S_ISVTX) < 0) | |
608 | return -errno; | |
c17ec25e | 609 | } |
15ae422b | 610 | |
613b411c LP |
611 | *path = x; |
612 | x = NULL; | |
613 | ||
614 | return 0; | |
615 | } | |
616 | ||
617 | int setup_tmp_dirs(const char *id, char **tmp_dir, char **var_tmp_dir) { | |
618 | char *a, *b; | |
619 | int r; | |
620 | ||
621 | assert(id); | |
622 | assert(tmp_dir); | |
623 | assert(var_tmp_dir); | |
624 | ||
625 | r = setup_one_tmp_dir(id, "/tmp", &a); | |
626 | if (r < 0) | |
627 | return r; | |
628 | ||
629 | r = setup_one_tmp_dir(id, "/var/tmp", &b); | |
630 | if (r < 0) { | |
631 | char *t; | |
632 | ||
63c372cb | 633 | t = strjoina(a, "/tmp"); |
613b411c LP |
634 | rmdir(t); |
635 | rmdir(a); | |
636 | ||
637 | free(a); | |
638 | return r; | |
639 | } | |
640 | ||
641 | *tmp_dir = a; | |
642 | *var_tmp_dir = b; | |
643 | ||
644 | return 0; | |
645 | } | |
646 | ||
647 | int setup_netns(int netns_storage_socket[2]) { | |
648 | _cleanup_close_ int netns = -1; | |
3ee897d6 | 649 | int r, q; |
613b411c LP |
650 | |
651 | assert(netns_storage_socket); | |
652 | assert(netns_storage_socket[0] >= 0); | |
653 | assert(netns_storage_socket[1] >= 0); | |
654 | ||
655 | /* We use the passed socketpair as a storage buffer for our | |
76cd584b LP |
656 | * namespace reference fd. Whatever process runs this first |
657 | * shall create a new namespace, all others should just join | |
658 | * it. To serialize that we use a file lock on the socket | |
659 | * pair. | |
613b411c LP |
660 | * |
661 | * It's a bit crazy, but hey, works great! */ | |
662 | ||
663 | if (lockf(netns_storage_socket[0], F_LOCK, 0) < 0) | |
664 | return -errno; | |
665 | ||
3ee897d6 LP |
666 | netns = receive_one_fd(netns_storage_socket[0], MSG_DONTWAIT); |
667 | if (netns == -EAGAIN) { | |
613b411c LP |
668 | /* Nothing stored yet, so let's create a new namespace */ |
669 | ||
670 | if (unshare(CLONE_NEWNET) < 0) { | |
671 | r = -errno; | |
672 | goto fail; | |
673 | } | |
674 | ||
675 | loopback_setup(); | |
676 | ||
677 | netns = open("/proc/self/ns/net", O_RDONLY|O_CLOEXEC|O_NOCTTY); | |
678 | if (netns < 0) { | |
679 | r = -errno; | |
680 | goto fail; | |
681 | } | |
682 | ||
683 | r = 1; | |
613b411c | 684 | |
3ee897d6 LP |
685 | } else if (netns < 0) { |
686 | r = netns; | |
687 | goto fail; | |
613b411c | 688 | |
3ee897d6 LP |
689 | } else { |
690 | /* Yay, found something, so let's join the namespace */ | |
613b411c LP |
691 | if (setns(netns, CLONE_NEWNET) < 0) { |
692 | r = -errno; | |
693 | goto fail; | |
694 | } | |
695 | ||
696 | r = 0; | |
697 | } | |
698 | ||
3ee897d6 LP |
699 | q = send_one_fd(netns_storage_socket[1], netns, MSG_DONTWAIT); |
700 | if (q < 0) { | |
701 | r = q; | |
613b411c LP |
702 | goto fail; |
703 | } | |
704 | ||
705 | fail: | |
706 | lockf(netns_storage_socket[0], F_ULOCK, 0); | |
15ae422b LP |
707 | return r; |
708 | } | |
417116f2 | 709 | |
1b8689f9 LP |
710 | static const char *const protect_home_table[_PROTECT_HOME_MAX] = { |
711 | [PROTECT_HOME_NO] = "no", | |
712 | [PROTECT_HOME_YES] = "yes", | |
713 | [PROTECT_HOME_READ_ONLY] = "read-only", | |
417116f2 LP |
714 | }; |
715 | ||
1b8689f9 LP |
716 | DEFINE_STRING_TABLE_LOOKUP(protect_home, ProtectHome); |
717 | ||
718 | static const char *const protect_system_table[_PROTECT_SYSTEM_MAX] = { | |
719 | [PROTECT_SYSTEM_NO] = "no", | |
720 | [PROTECT_SYSTEM_YES] = "yes", | |
721 | [PROTECT_SYSTEM_FULL] = "full", | |
722 | }; | |
723 | ||
724 | DEFINE_STRING_TABLE_LOOKUP(protect_system, ProtectSystem); |