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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
15ae422b LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2010 Lennart Poettering | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
5430f7f2 LP |
8 | under the terms of the GNU Lesser General Public License as published by |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
15ae422b LP |
10 | (at your option) any later version. |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
5430f7f2 | 15 | Lesser General Public License for more details. |
15ae422b | 16 | |
5430f7f2 | 17 | You should have received a copy of the GNU Lesser General Public License |
15ae422b LP |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. |
19 | ***/ | |
20 | ||
21 | #include <errno.h> | |
07630cea | 22 | #include <sched.h> |
15ae422b | 23 | #include <stdio.h> |
07630cea LP |
24 | #include <string.h> |
25 | #include <sys/mount.h> | |
15ae422b | 26 | #include <sys/stat.h> |
07630cea | 27 | #include <unistd.h> |
25e870b5 | 28 | #include <linux/fs.h> |
15ae422b | 29 | |
b5efdb8a | 30 | #include "alloc-util.h" |
10404d52 | 31 | #include "base-filesystem.h" |
7f112f50 | 32 | #include "dev-setup.h" |
3ffd4af2 | 33 | #include "fd-util.h" |
d944dc95 | 34 | #include "fs-util.h" |
e908468b | 35 | #include "label.h" |
915e6d16 | 36 | #include "loop-util.h" |
07630cea LP |
37 | #include "loopback-setup.h" |
38 | #include "missing.h" | |
39 | #include "mkdir.h" | |
4349cd7c | 40 | #include "mount-util.h" |
3ffd4af2 | 41 | #include "namespace.h" |
07630cea | 42 | #include "path-util.h" |
d7b8eec7 | 43 | #include "selinux-util.h" |
2583fbea | 44 | #include "socket-util.h" |
36ce7110 | 45 | #include "stat-util.h" |
8b43440b | 46 | #include "string-table.h" |
07630cea LP |
47 | #include "string-util.h" |
48 | #include "strv.h" | |
affb60b1 | 49 | #include "umask-util.h" |
ee104e11 | 50 | #include "user-util.h" |
07630cea | 51 | #include "util.h" |
15ae422b | 52 | |
737ba3c8 | 53 | #define DEV_MOUNT_OPTIONS (MS_NOSUID|MS_STRICTATIME|MS_NOEXEC) |
54 | ||
c17ec25e | 55 | typedef enum MountMode { |
15ae422b LP |
56 | /* This is ordered by priority! */ |
57 | INACCESSIBLE, | |
d2d6c096 LP |
58 | BIND_MOUNT, |
59 | BIND_MOUNT_RECURSIVE, | |
ac0930c8 | 60 | PRIVATE_TMP, |
7f112f50 | 61 | PRIVATE_DEV, |
5d997827 | 62 | BIND_DEV, |
6c47cd7d | 63 | EMPTY_DIR, |
5d997827 LP |
64 | SYSFS, |
65 | PROCFS, | |
66 | READONLY, | |
59eeb84b | 67 | READWRITE, |
2abd4e38 | 68 | TMPFS, |
c17ec25e | 69 | } MountMode; |
15ae422b | 70 | |
34de407a | 71 | typedef struct MountEntry { |
5327c910 | 72 | const char *path_const; /* Memory allocated on stack or static */ |
cfbeb4ef | 73 | MountMode mode:5; |
5327c910 LP |
74 | bool ignore:1; /* Ignore if path does not exist? */ |
75 | bool has_prefix:1; /* Already is prefixed by the root dir? */ | |
cfbeb4ef | 76 | bool read_only:1; /* Shall this mount point be read-only? */ |
55fe7432 | 77 | char *path_malloc; /* Use this instead of 'path_const' if we had to allocate memory */ |
d2d6c096 LP |
78 | const char *source_const; /* The source path, for bind mounts */ |
79 | char *source_malloc; | |
2abd4e38 YW |
80 | const char *options_const;/* Mount options for tmpfs */ |
81 | char *options_malloc; | |
82 | unsigned long flags; /* Mount flags used by EMPTY_DIR and TMPFS. Do not include MS_RDONLY here, but please use read_only. */ | |
34de407a | 83 | } MountEntry; |
15ae422b | 84 | |
5d997827 LP |
85 | /* If MountAPIVFS= is used, let's mount /sys and /proc into the it, but only as a fallback if the user hasn't mounted |
86 | * something there already. These mounts are hence overriden by any other explicitly configured mounts. */ | |
87 | static const MountEntry apivfs_table[] = { | |
88 | { "/proc", PROCFS, false }, | |
89 | { "/dev", BIND_DEV, false }, | |
90 | { "/sys", SYSFS, false }, | |
91 | }; | |
f471b2af | 92 | |
11a30cec | 93 | /* ProtectKernelTunables= option and the related filesystem APIs */ |
34de407a | 94 | static const MountEntry protect_kernel_tunables_table[] = { |
c6232fb0 LP |
95 | { "/proc/sys", READONLY, false }, |
96 | { "/proc/sysrq-trigger", READONLY, true }, | |
97 | { "/proc/latency_stats", READONLY, true }, | |
98 | { "/proc/mtrr", READONLY, true }, | |
aa70f38b | 99 | { "/proc/apm", READONLY, true }, /* Obsolete API, there's no point in permitting access to this, ever */ |
c6232fb0 LP |
100 | { "/proc/acpi", READONLY, true }, |
101 | { "/proc/timer_stats", READONLY, true }, | |
102 | { "/proc/asound", READONLY, true }, | |
103 | { "/proc/bus", READONLY, true }, | |
104 | { "/proc/fs", READONLY, true }, | |
105 | { "/proc/irq", READONLY, true }, | |
106 | { "/sys", READONLY, false }, | |
107 | { "/sys/kernel/debug", READONLY, true }, | |
108 | { "/sys/kernel/tracing", READONLY, true }, | |
13a141f0 | 109 | { "/sys/fs/bpf", READONLY, true }, |
c6232fb0 | 110 | { "/sys/fs/cgroup", READWRITE, false }, /* READONLY is set by ProtectControlGroups= option */ |
3a0bf6d6 | 111 | { "/sys/fs/selinux", READWRITE, true }, |
11a30cec DH |
112 | }; |
113 | ||
c575770b | 114 | /* ProtectKernelModules= option */ |
34de407a | 115 | static const MountEntry protect_kernel_modules_table[] = { |
349cc4a5 | 116 | #if HAVE_SPLIT_USR |
c6232fb0 | 117 | { "/lib/modules", INACCESSIBLE, true }, |
c575770b | 118 | #endif |
c6232fb0 | 119 | { "/usr/lib/modules", INACCESSIBLE, true }, |
c575770b DH |
120 | }; |
121 | ||
b6c432ca DH |
122 | /* |
123 | * ProtectHome=read-only table, protect $HOME and $XDG_RUNTIME_DIR and rest of | |
124 | * system should be protected by ProtectSystem= | |
125 | */ | |
34de407a | 126 | static const MountEntry protect_home_read_only_table[] = { |
c6232fb0 LP |
127 | { "/home", READONLY, true }, |
128 | { "/run/user", READONLY, true }, | |
129 | { "/root", READONLY, true }, | |
b6c432ca DH |
130 | }; |
131 | ||
e4da7d8c YW |
132 | /* ProtectHome=tmpfs table */ |
133 | static const MountEntry protect_home_tmpfs_table[] = { | |
134 | { "/home", TMPFS, true, .read_only = true, .options_const = "mode=0755", .flags = MS_NODEV|MS_STRICTATIME }, | |
135 | { "/run/user", TMPFS, true, .read_only = true, .options_const = "mode=0755", .flags = MS_NODEV|MS_STRICTATIME }, | |
136 | { "/root", TMPFS, true, .read_only = true, .options_const = "mode=0700", .flags = MS_NODEV|MS_STRICTATIME }, | |
137 | }; | |
138 | ||
b6c432ca | 139 | /* ProtectHome=yes table */ |
34de407a | 140 | static const MountEntry protect_home_yes_table[] = { |
c6232fb0 LP |
141 | { "/home", INACCESSIBLE, true }, |
142 | { "/run/user", INACCESSIBLE, true }, | |
143 | { "/root", INACCESSIBLE, true }, | |
b6c432ca DH |
144 | }; |
145 | ||
f471b2af | 146 | /* ProtectSystem=yes table */ |
34de407a | 147 | static const MountEntry protect_system_yes_table[] = { |
c6232fb0 LP |
148 | { "/usr", READONLY, false }, |
149 | { "/boot", READONLY, true }, | |
150 | { "/efi", READONLY, true }, | |
7486f305 AB |
151 | #if HAVE_SPLIT_USR |
152 | { "/lib", READONLY, true }, | |
153 | { "/lib64", READONLY, true }, | |
154 | { "/bin", READONLY, true }, | |
155 | { "/sbin", READONLY, true }, | |
156 | #endif | |
f471b2af DH |
157 | }; |
158 | ||
159 | /* ProtectSystem=full includes ProtectSystem=yes */ | |
34de407a | 160 | static const MountEntry protect_system_full_table[] = { |
c6232fb0 LP |
161 | { "/usr", READONLY, false }, |
162 | { "/boot", READONLY, true }, | |
163 | { "/efi", READONLY, true }, | |
164 | { "/etc", READONLY, false }, | |
7486f305 AB |
165 | #if HAVE_SPLIT_USR |
166 | { "/lib", READONLY, true }, | |
167 | { "/lib64", READONLY, true }, | |
168 | { "/bin", READONLY, true }, | |
169 | { "/sbin", READONLY, true }, | |
170 | #endif | |
f471b2af DH |
171 | }; |
172 | ||
173 | /* | |
174 | * ProtectSystem=strict table. In this strict mode, we mount everything | |
175 | * read-only, except for /proc, /dev, /sys which are the kernel API VFS, | |
176 | * which are left writable, but PrivateDevices= + ProtectKernelTunables= | |
177 | * protect those, and these options should be fully orthogonal. | |
178 | * (And of course /home and friends are also left writable, as ProtectHome= | |
179 | * shall manage those, orthogonally). | |
180 | */ | |
34de407a | 181 | static const MountEntry protect_system_strict_table[] = { |
ddbe0412 LP |
182 | { "/", READONLY, false }, |
183 | { "/proc", READWRITE, false }, /* ProtectKernelTunables= */ | |
184 | { "/sys", READWRITE, false }, /* ProtectKernelTunables= */ | |
185 | { "/dev", READWRITE, false }, /* PrivateDevices= */ | |
186 | { "/home", READWRITE, true }, /* ProtectHome= */ | |
187 | { "/run/user", READWRITE, true }, /* ProtectHome= */ | |
188 | { "/root", READWRITE, true }, /* ProtectHome= */ | |
f471b2af DH |
189 | }; |
190 | ||
34de407a | 191 | static const char *mount_entry_path(const MountEntry *p) { |
f0a4feb0 DH |
192 | assert(p); |
193 | ||
5327c910 LP |
194 | /* Returns the path of this bind mount. If the malloc()-allocated ->path_buffer field is set we return that, |
195 | * otherwise the stack/static ->path field is returned. */ | |
f0a4feb0 | 196 | |
5327c910 | 197 | return p->path_malloc ?: p->path_const; |
f0a4feb0 DH |
198 | } |
199 | ||
34de407a | 200 | static bool mount_entry_read_only(const MountEntry *p) { |
cfbeb4ef LP |
201 | assert(p); |
202 | ||
203 | return p->read_only || IN_SET(p->mode, READONLY, INACCESSIBLE); | |
204 | } | |
205 | ||
d2d6c096 LP |
206 | static const char *mount_entry_source(const MountEntry *p) { |
207 | assert(p); | |
208 | ||
209 | return p->source_malloc ?: p->source_const; | |
210 | } | |
211 | ||
2abd4e38 YW |
212 | static const char *mount_entry_options(const MountEntry *p) { |
213 | assert(p); | |
214 | ||
215 | return p->options_malloc ?: p->options_const; | |
216 | } | |
217 | ||
1eb7e08e LP |
218 | static void mount_entry_done(MountEntry *p) { |
219 | assert(p); | |
220 | ||
221 | p->path_malloc = mfree(p->path_malloc); | |
222 | p->source_malloc = mfree(p->source_malloc); | |
2abd4e38 | 223 | p->options_malloc = mfree(p->options_malloc); |
1eb7e08e LP |
224 | } |
225 | ||
d18aff04 | 226 | static int append_access_mounts(MountEntry **p, char **strv, MountMode mode, bool forcibly_require_prefix) { |
15ae422b LP |
227 | char **i; |
228 | ||
613b411c LP |
229 | assert(p); |
230 | ||
5327c910 LP |
231 | /* Adds a list of user-supplied READWRITE/READONLY/INACCESSIBLE entries */ |
232 | ||
15ae422b | 233 | STRV_FOREACH(i, strv) { |
5327c910 LP |
234 | bool ignore = false, needs_prefix = false; |
235 | const char *e = *i; | |
15ae422b | 236 | |
5327c910 LP |
237 | /* Look for any prefixes */ |
238 | if (startswith(e, "-")) { | |
239 | e++; | |
9c94d52e | 240 | ignore = true; |
ea92ae33 | 241 | } |
5327c910 LP |
242 | if (startswith(e, "+")) { |
243 | e++; | |
244 | needs_prefix = true; | |
245 | } | |
ea92ae33 | 246 | |
5327c910 | 247 | if (!path_is_absolute(e)) |
15ae422b LP |
248 | return -EINVAL; |
249 | ||
34de407a | 250 | *((*p)++) = (MountEntry) { |
5327c910 LP |
251 | .path_const = e, |
252 | .mode = mode, | |
253 | .ignore = ignore, | |
d18aff04 | 254 | .has_prefix = !needs_prefix && !forcibly_require_prefix, |
5327c910 | 255 | }; |
15ae422b LP |
256 | } |
257 | ||
258 | return 0; | |
259 | } | |
260 | ||
6c47cd7d LP |
261 | static int append_empty_dir_mounts(MountEntry **p, char **strv) { |
262 | char **i; | |
263 | ||
264 | assert(p); | |
265 | ||
266 | /* Adds tmpfs mounts to provide readable but empty directories. This is primarily used to implement the | |
267 | * "/private/" boundary directories for DynamicUser=1. */ | |
268 | ||
269 | STRV_FOREACH(i, strv) { | |
270 | ||
271 | *((*p)++) = (MountEntry) { | |
272 | .path_const = *i, | |
273 | .mode = EMPTY_DIR, | |
274 | .ignore = false, | |
275 | .has_prefix = false, | |
276 | .read_only = true, | |
2abd4e38 YW |
277 | .options_const = "mode=755", |
278 | .flags = MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, | |
6c47cd7d LP |
279 | }; |
280 | } | |
281 | ||
282 | return 0; | |
283 | } | |
284 | ||
d2d6c096 LP |
285 | static int append_bind_mounts(MountEntry **p, const BindMount *binds, unsigned n) { |
286 | unsigned i; | |
287 | ||
288 | assert(p); | |
289 | ||
290 | for (i = 0; i < n; i++) { | |
291 | const BindMount *b = binds + i; | |
292 | ||
293 | *((*p)++) = (MountEntry) { | |
294 | .path_const = b->destination, | |
295 | .mode = b->recursive ? BIND_MOUNT_RECURSIVE : BIND_MOUNT, | |
296 | .read_only = b->read_only, | |
297 | .source_const = b->source, | |
4ca763a9 | 298 | .ignore = b->ignore_enoent, |
d2d6c096 LP |
299 | }; |
300 | } | |
301 | ||
302 | return 0; | |
303 | } | |
304 | ||
2abd4e38 YW |
305 | static int append_tmpfs_mounts(MountEntry **p, const TemporaryFileSystem *tmpfs, unsigned n) { |
306 | unsigned i; | |
307 | int r; | |
308 | ||
309 | assert(p); | |
310 | ||
311 | for (i = 0; i < n; i++) { | |
312 | const TemporaryFileSystem *t = tmpfs + i; | |
313 | _cleanup_free_ char *o = NULL, *str = NULL; | |
314 | unsigned long flags = MS_NODEV|MS_STRICTATIME; | |
315 | bool ro = false; | |
316 | ||
317 | if (!path_is_absolute(t->path)) | |
318 | return -EINVAL; | |
319 | ||
320 | if (!isempty(t->options)) { | |
321 | str = strjoin("mode=0755,", t->options); | |
322 | if (!str) | |
323 | return -ENOMEM; | |
324 | ||
325 | r = mount_option_mangle(str, MS_NODEV|MS_STRICTATIME, &flags, &o); | |
326 | if (r < 0) | |
327 | return r; | |
328 | ||
329 | ro = !!(flags & MS_RDONLY); | |
330 | if (ro) | |
331 | flags ^= MS_RDONLY; | |
332 | } | |
333 | ||
334 | *((*p)++) = (MountEntry) { | |
335 | .path_const = t->path, | |
336 | .mode = TMPFS, | |
337 | .read_only = ro, | |
338 | .options_malloc = o, | |
339 | .flags = flags, | |
340 | }; | |
341 | ||
342 | o = NULL; | |
343 | } | |
344 | ||
345 | return 0; | |
346 | } | |
347 | ||
34de407a | 348 | static int append_static_mounts(MountEntry **p, const MountEntry *mounts, unsigned n, bool ignore_protect) { |
f471b2af | 349 | unsigned i; |
11a30cec DH |
350 | |
351 | assert(p); | |
f471b2af | 352 | assert(mounts); |
11a30cec | 353 | |
5327c910 | 354 | /* Adds a list of static pre-defined entries */ |
f471b2af | 355 | |
5327c910 | 356 | for (i = 0; i < n; i++) |
34de407a LP |
357 | *((*p)++) = (MountEntry) { |
358 | .path_const = mount_entry_path(mounts+i), | |
5327c910 LP |
359 | .mode = mounts[i].mode, |
360 | .ignore = mounts[i].ignore || ignore_protect, | |
361 | }; | |
f471b2af DH |
362 | |
363 | return 0; | |
364 | } | |
365 | ||
34de407a | 366 | static int append_protect_home(MountEntry **p, ProtectHome protect_home, bool ignore_protect) { |
c575770b DH |
367 | assert(p); |
368 | ||
5327c910 | 369 | switch (protect_home) { |
b6c432ca | 370 | |
5327c910 | 371 | case PROTECT_HOME_NO: |
b6c432ca DH |
372 | return 0; |
373 | ||
b6c432ca | 374 | case PROTECT_HOME_READ_ONLY: |
5327c910 LP |
375 | return append_static_mounts(p, protect_home_read_only_table, ELEMENTSOF(protect_home_read_only_table), ignore_protect); |
376 | ||
e4da7d8c YW |
377 | case PROTECT_HOME_TMPFS: |
378 | return append_static_mounts(p, protect_home_tmpfs_table, ELEMENTSOF(protect_home_tmpfs_table), ignore_protect); | |
379 | ||
b6c432ca | 380 | case PROTECT_HOME_YES: |
5327c910 LP |
381 | return append_static_mounts(p, protect_home_yes_table, ELEMENTSOF(protect_home_yes_table), ignore_protect); |
382 | ||
b6c432ca | 383 | default: |
5327c910 | 384 | assert_not_reached("Unexpected ProtectHome= value"); |
b6c432ca | 385 | } |
b6c432ca DH |
386 | } |
387 | ||
34de407a | 388 | static int append_protect_system(MountEntry **p, ProtectSystem protect_system, bool ignore_protect) { |
f471b2af DH |
389 | assert(p); |
390 | ||
5327c910 LP |
391 | switch (protect_system) { |
392 | ||
393 | case PROTECT_SYSTEM_NO: | |
f471b2af DH |
394 | return 0; |
395 | ||
f471b2af | 396 | case PROTECT_SYSTEM_STRICT: |
5327c910 LP |
397 | return append_static_mounts(p, protect_system_strict_table, ELEMENTSOF(protect_system_strict_table), ignore_protect); |
398 | ||
f471b2af | 399 | case PROTECT_SYSTEM_YES: |
5327c910 LP |
400 | return append_static_mounts(p, protect_system_yes_table, ELEMENTSOF(protect_system_yes_table), ignore_protect); |
401 | ||
f471b2af | 402 | case PROTECT_SYSTEM_FULL: |
5327c910 LP |
403 | return append_static_mounts(p, protect_system_full_table, ELEMENTSOF(protect_system_full_table), ignore_protect); |
404 | ||
f471b2af | 405 | default: |
5327c910 | 406 | assert_not_reached("Unexpected ProtectSystem= value"); |
f471b2af | 407 | } |
11a30cec DH |
408 | } |
409 | ||
c17ec25e | 410 | static int mount_path_compare(const void *a, const void *b) { |
34de407a | 411 | const MountEntry *p = a, *q = b; |
a0827e2b | 412 | int d; |
15ae422b | 413 | |
6ee1a919 | 414 | /* If the paths are not equal, then order prefixes first */ |
34de407a | 415 | d = path_compare(mount_entry_path(p), mount_entry_path(q)); |
6ee1a919 LP |
416 | if (d != 0) |
417 | return d; | |
15ae422b | 418 | |
6ee1a919 LP |
419 | /* If the paths are equal, check the mode */ |
420 | if (p->mode < q->mode) | |
421 | return -1; | |
15ae422b | 422 | |
6ee1a919 LP |
423 | if (p->mode > q->mode) |
424 | return 1; | |
15ae422b | 425 | |
6ee1a919 | 426 | return 0; |
15ae422b LP |
427 | } |
428 | ||
34de407a | 429 | static int prefix_where_needed(MountEntry *m, unsigned n, const char *root_directory) { |
5327c910 LP |
430 | unsigned i; |
431 | ||
432 | /* Prefixes all paths in the bind mount table with the root directory if it is specified and the entry needs | |
433 | * that. */ | |
434 | ||
435 | if (!root_directory) | |
436 | return 0; | |
437 | ||
438 | for (i = 0; i < n; i++) { | |
439 | char *s; | |
440 | ||
441 | if (m[i].has_prefix) | |
442 | continue; | |
443 | ||
34de407a | 444 | s = prefix_root(root_directory, mount_entry_path(m+i)); |
5327c910 LP |
445 | if (!s) |
446 | return -ENOMEM; | |
447 | ||
e282f51f | 448 | free_and_replace(m[i].path_malloc, s); |
5327c910 LP |
449 | m[i].has_prefix = true; |
450 | } | |
451 | ||
452 | return 0; | |
453 | } | |
454 | ||
34de407a LP |
455 | static void drop_duplicates(MountEntry *m, unsigned *n) { |
456 | MountEntry *f, *t, *previous; | |
15ae422b | 457 | |
c17ec25e | 458 | assert(m); |
15ae422b | 459 | assert(n); |
15ae422b | 460 | |
fe3c2583 LP |
461 | /* Drops duplicate entries. Expects that the array is properly ordered already. */ |
462 | ||
1d54cd5d | 463 | for (f = m, t = m, previous = NULL; f < m + *n; f++) { |
15ae422b | 464 | |
fe3c2583 LP |
465 | /* The first one wins (which is the one with the more restrictive mode), see mount_path_compare() |
466 | * above. */ | |
34de407a LP |
467 | if (previous && path_equal(mount_entry_path(f), mount_entry_path(previous))) { |
468 | log_debug("%s is duplicate.", mount_entry_path(f)); | |
469 | previous->read_only = previous->read_only || mount_entry_read_only(f); /* Propagate the read-only flag to the remaining entry */ | |
1eb7e08e | 470 | mount_entry_done(f); |
15ae422b | 471 | continue; |
fe3c2583 | 472 | } |
15ae422b | 473 | |
e2d7c1a0 | 474 | *t = *f; |
15ae422b | 475 | previous = t; |
fe3c2583 LP |
476 | t++; |
477 | } | |
478 | ||
479 | *n = t - m; | |
480 | } | |
481 | ||
34de407a LP |
482 | static void drop_inaccessible(MountEntry *m, unsigned *n) { |
483 | MountEntry *f, *t; | |
fe3c2583 LP |
484 | const char *clear = NULL; |
485 | ||
486 | assert(m); | |
487 | assert(n); | |
488 | ||
489 | /* Drops all entries obstructed by another entry further up the tree. Expects that the array is properly | |
490 | * ordered already. */ | |
491 | ||
1d54cd5d | 492 | for (f = m, t = m; f < m + *n; f++) { |
fe3c2583 LP |
493 | |
494 | /* If we found a path set for INACCESSIBLE earlier, and this entry has it as prefix we should drop | |
495 | * it, as inaccessible paths really should drop the entire subtree. */ | |
34de407a LP |
496 | if (clear && path_startswith(mount_entry_path(f), clear)) { |
497 | log_debug("%s is masked by %s.", mount_entry_path(f), clear); | |
1eb7e08e | 498 | mount_entry_done(f); |
fe3c2583 LP |
499 | continue; |
500 | } | |
15ae422b | 501 | |
34de407a | 502 | clear = f->mode == INACCESSIBLE ? mount_entry_path(f) : NULL; |
fe3c2583 LP |
503 | |
504 | *t = *f; | |
15ae422b LP |
505 | t++; |
506 | } | |
507 | ||
c17ec25e | 508 | *n = t - m; |
15ae422b LP |
509 | } |
510 | ||
34de407a LP |
511 | static void drop_nop(MountEntry *m, unsigned *n) { |
512 | MountEntry *f, *t; | |
7648a565 LP |
513 | |
514 | assert(m); | |
515 | assert(n); | |
516 | ||
517 | /* Drops all entries which have an immediate parent that has the same type, as they are redundant. Assumes the | |
518 | * list is ordered by prefixes. */ | |
519 | ||
1d54cd5d | 520 | for (f = m, t = m; f < m + *n; f++) { |
7648a565 LP |
521 | |
522 | /* Only suppress such subtrees for READONLY and READWRITE entries */ | |
523 | if (IN_SET(f->mode, READONLY, READWRITE)) { | |
34de407a | 524 | MountEntry *p; |
7648a565 LP |
525 | bool found = false; |
526 | ||
527 | /* Now let's find the first parent of the entry we are looking at. */ | |
528 | for (p = t-1; p >= m; p--) { | |
34de407a | 529 | if (path_startswith(mount_entry_path(f), mount_entry_path(p))) { |
7648a565 LP |
530 | found = true; |
531 | break; | |
532 | } | |
533 | } | |
534 | ||
535 | /* We found it, let's see if it's the same mode, if so, we can drop this entry */ | |
536 | if (found && p->mode == f->mode) { | |
34de407a | 537 | log_debug("%s is redundant by %s", mount_entry_path(f), mount_entry_path(p)); |
1eb7e08e | 538 | mount_entry_done(f); |
7648a565 LP |
539 | continue; |
540 | } | |
541 | } | |
542 | ||
543 | *t = *f; | |
544 | t++; | |
545 | } | |
546 | ||
547 | *n = t - m; | |
548 | } | |
549 | ||
34de407a LP |
550 | static void drop_outside_root(const char *root_directory, MountEntry *m, unsigned *n) { |
551 | MountEntry *f, *t; | |
cd2902c9 LP |
552 | |
553 | assert(m); | |
554 | assert(n); | |
555 | ||
1d54cd5d | 556 | /* Nothing to do */ |
cd2902c9 LP |
557 | if (!root_directory) |
558 | return; | |
559 | ||
560 | /* Drops all mounts that are outside of the root directory. */ | |
561 | ||
1d54cd5d | 562 | for (f = m, t = m; f < m + *n; f++) { |
cd2902c9 | 563 | |
34de407a LP |
564 | if (!path_startswith(mount_entry_path(f), root_directory)) { |
565 | log_debug("%s is outside of root directory.", mount_entry_path(f)); | |
1eb7e08e | 566 | mount_entry_done(f); |
cd2902c9 LP |
567 | continue; |
568 | } | |
569 | ||
570 | *t = *f; | |
571 | t++; | |
572 | } | |
573 | ||
574 | *n = t - m; | |
575 | } | |
576 | ||
414b304b | 577 | static int clone_device_node(const char *d, const char *temporary_mount) { |
6f7f3a33 | 578 | const char *dn; |
b5e99f23 ДГ |
579 | struct stat st; |
580 | int r; | |
581 | ||
414b304b | 582 | if (stat(d, &st) < 0) { |
b5e99f23 ДГ |
583 | if (errno == ENOENT) |
584 | return 0; | |
585 | return -errno; | |
586 | } | |
587 | ||
588 | if (!S_ISBLK(st.st_mode) && | |
589 | !S_ISCHR(st.st_mode)) | |
590 | return -EINVAL; | |
591 | ||
592 | if (st.st_rdev == 0) | |
593 | return 0; | |
594 | ||
6f7f3a33 | 595 | dn = strjoina(temporary_mount, d); |
b5e99f23 ДГ |
596 | |
597 | mac_selinux_create_file_prepare(d, st.st_mode); | |
598 | r = mknod(dn, st.st_mode, st.st_rdev); | |
599 | mac_selinux_create_file_clear(); | |
b5e99f23 | 600 | if (r < 0) |
225874dc | 601 | return log_debug_errno(errno, "mknod failed for %s: %m", d); |
b5e99f23 | 602 | |
98b1d2b8 | 603 | return 1; |
b5e99f23 ДГ |
604 | } |
605 | ||
5d997827 | 606 | static int mount_private_dev(MountEntry *m) { |
7f112f50 LP |
607 | static const char devnodes[] = |
608 | "/dev/null\0" | |
609 | "/dev/zero\0" | |
610 | "/dev/full\0" | |
611 | "/dev/random\0" | |
612 | "/dev/urandom\0" | |
613 | "/dev/tty\0"; | |
614 | ||
2b85f4e1 | 615 | char temporary_mount[] = "/tmp/namespace-dev-XXXXXX"; |
63cc4c31 | 616 | const char *d, *dev = NULL, *devpts = NULL, *devshm = NULL, *devhugepages = NULL, *devmqueue = NULL, *devlog = NULL, *devptmx = NULL; |
7f112f50 LP |
617 | _cleanup_umask_ mode_t u; |
618 | int r; | |
619 | ||
620 | assert(m); | |
621 | ||
622 | u = umask(0000); | |
623 | ||
2b85f4e1 LP |
624 | if (!mkdtemp(temporary_mount)) |
625 | return -errno; | |
626 | ||
63c372cb | 627 | dev = strjoina(temporary_mount, "/dev"); |
dc751688 | 628 | (void) mkdir(dev, 0755); |
737ba3c8 | 629 | if (mount("tmpfs", dev, "tmpfs", DEV_MOUNT_OPTIONS, "mode=755") < 0) { |
2b85f4e1 LP |
630 | r = -errno; |
631 | goto fail; | |
632 | } | |
633 | ||
63c372cb | 634 | devpts = strjoina(temporary_mount, "/dev/pts"); |
dc751688 | 635 | (void) mkdir(devpts, 0755); |
2b85f4e1 LP |
636 | if (mount("/dev/pts", devpts, NULL, MS_BIND, NULL) < 0) { |
637 | r = -errno; | |
638 | goto fail; | |
639 | } | |
640 | ||
414b304b ДГ |
641 | /* /dev/ptmx can either be a device node or a symlink to /dev/pts/ptmx |
642 | * when /dev/ptmx a device node, /dev/pts/ptmx has 000 permissions making it inaccessible | |
643 | * thus, in that case make a clone | |
644 | * | |
645 | * in nspawn and other containers it will be a symlink, in that case make it a symlink | |
646 | */ | |
36ce7110 LP |
647 | r = is_symlink("/dev/ptmx"); |
648 | if (r < 0) | |
3164e3cb | 649 | goto fail; |
36ce7110 | 650 | if (r > 0) { |
414b304b ДГ |
651 | devptmx = strjoina(temporary_mount, "/dev/ptmx"); |
652 | if (symlink("pts/ptmx", devptmx) < 0) { | |
653 | r = -errno; | |
654 | goto fail; | |
655 | } | |
656 | } else { | |
657 | r = clone_device_node("/dev/ptmx", temporary_mount); | |
152c475f LP |
658 | if (r < 0) |
659 | goto fail; | |
660 | if (r == 0) { | |
661 | r = -ENXIO; | |
414b304b | 662 | goto fail; |
152c475f | 663 | } |
414b304b | 664 | } |
e06b6479 | 665 | |
63c372cb | 666 | devshm = strjoina(temporary_mount, "/dev/shm"); |
8d953682 | 667 | (void) mkdir(devshm, 0755); |
2b85f4e1 LP |
668 | r = mount("/dev/shm", devshm, NULL, MS_BIND, NULL); |
669 | if (r < 0) { | |
670 | r = -errno; | |
671 | goto fail; | |
672 | } | |
673 | ||
63c372cb | 674 | devmqueue = strjoina(temporary_mount, "/dev/mqueue"); |
dc751688 | 675 | (void) mkdir(devmqueue, 0755); |
3164e3cb | 676 | (void) mount("/dev/mqueue", devmqueue, NULL, MS_BIND, NULL); |
2b85f4e1 | 677 | |
63c372cb | 678 | devhugepages = strjoina(temporary_mount, "/dev/hugepages"); |
dc751688 | 679 | (void) mkdir(devhugepages, 0755); |
3164e3cb | 680 | (void) mount("/dev/hugepages", devhugepages, NULL, MS_BIND, NULL); |
2b85f4e1 | 681 | |
63c372cb | 682 | devlog = strjoina(temporary_mount, "/dev/log"); |
3164e3cb | 683 | (void) symlink("/run/systemd/journal/dev-log", devlog); |
82d25240 | 684 | |
7f112f50 | 685 | NULSTR_FOREACH(d, devnodes) { |
b5e99f23 ДГ |
686 | r = clone_device_node(d, temporary_mount); |
687 | if (r < 0) | |
2b85f4e1 | 688 | goto fail; |
7f112f50 LP |
689 | } |
690 | ||
03cfe0d5 | 691 | dev_setup(temporary_mount, UID_INVALID, GID_INVALID); |
7f112f50 | 692 | |
ee818b89 AC |
693 | /* Create the /dev directory if missing. It is more likely to be |
694 | * missing when the service is started with RootDirectory. This is | |
695 | * consistent with mount units creating the mount points when missing. | |
696 | */ | |
34de407a | 697 | (void) mkdir_p_label(mount_entry_path(m), 0755); |
ee818b89 | 698 | |
9e5f8252 | 699 | /* Unmount everything in old /dev */ |
34de407a LP |
700 | umount_recursive(mount_entry_path(m), 0); |
701 | if (mount(dev, mount_entry_path(m), NULL, MS_MOVE, NULL) < 0) { | |
2b85f4e1 LP |
702 | r = -errno; |
703 | goto fail; | |
704 | } | |
7f112f50 | 705 | |
2b85f4e1 LP |
706 | rmdir(dev); |
707 | rmdir(temporary_mount); | |
7f112f50 | 708 | |
2b85f4e1 | 709 | return 0; |
7f112f50 | 710 | |
2b85f4e1 LP |
711 | fail: |
712 | if (devpts) | |
713 | umount(devpts); | |
7f112f50 | 714 | |
2b85f4e1 LP |
715 | if (devshm) |
716 | umount(devshm); | |
7f112f50 | 717 | |
2b85f4e1 LP |
718 | if (devhugepages) |
719 | umount(devhugepages); | |
7f112f50 | 720 | |
2b85f4e1 LP |
721 | if (devmqueue) |
722 | umount(devmqueue); | |
7f112f50 | 723 | |
d267c5aa ZJS |
724 | umount(dev); |
725 | rmdir(dev); | |
2b85f4e1 | 726 | rmdir(temporary_mount); |
7f112f50 | 727 | |
2b85f4e1 | 728 | return r; |
7f112f50 LP |
729 | } |
730 | ||
2a2969fd | 731 | static int mount_bind_dev(const MountEntry *m) { |
5d997827 LP |
732 | int r; |
733 | ||
734 | assert(m); | |
735 | ||
736 | /* Implements the little brother of mount_private_dev(): simply bind mounts the host's /dev into the service's | |
737 | * /dev. This is only used when RootDirectory= is set. */ | |
738 | ||
645767d6 LP |
739 | (void) mkdir_p_label(mount_entry_path(m), 0755); |
740 | ||
5d997827 LP |
741 | r = path_is_mount_point(mount_entry_path(m), NULL, 0); |
742 | if (r < 0) | |
743 | return log_debug_errno(r, "Unable to determine whether /dev is already mounted: %m"); | |
744 | if (r > 0) /* make this a NOP if /dev is already a mount point */ | |
745 | return 0; | |
746 | ||
747 | if (mount("/dev", mount_entry_path(m), NULL, MS_BIND|MS_REC, NULL) < 0) | |
748 | return log_debug_errno(errno, "Failed to bind mount %s: %m", mount_entry_path(m)); | |
749 | ||
750 | return 1; | |
751 | } | |
752 | ||
2a2969fd | 753 | static int mount_sysfs(const MountEntry *m) { |
5d997827 LP |
754 | int r; |
755 | ||
756 | assert(m); | |
757 | ||
645767d6 LP |
758 | (void) mkdir_p_label(mount_entry_path(m), 0755); |
759 | ||
5d997827 LP |
760 | r = path_is_mount_point(mount_entry_path(m), NULL, 0); |
761 | if (r < 0) | |
762 | return log_debug_errno(r, "Unable to determine whether /sys is already mounted: %m"); | |
763 | if (r > 0) /* make this a NOP if /sys is already a mount point */ | |
764 | return 0; | |
765 | ||
766 | /* Bind mount the host's version so that we get all child mounts of it, too. */ | |
767 | if (mount("/sys", mount_entry_path(m), NULL, MS_BIND|MS_REC, NULL) < 0) | |
768 | return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m)); | |
769 | ||
770 | return 1; | |
771 | } | |
772 | ||
2a2969fd | 773 | static int mount_procfs(const MountEntry *m) { |
5d997827 LP |
774 | int r; |
775 | ||
776 | assert(m); | |
777 | ||
645767d6 LP |
778 | (void) mkdir_p_label(mount_entry_path(m), 0755); |
779 | ||
5d997827 LP |
780 | r = path_is_mount_point(mount_entry_path(m), NULL, 0); |
781 | if (r < 0) | |
782 | return log_debug_errno(r, "Unable to determine whether /proc is already mounted: %m"); | |
783 | if (r > 0) /* make this a NOP if /proc is already a mount point */ | |
784 | return 0; | |
785 | ||
786 | /* Mount a new instance, so that we get the one that matches our user namespace, if we are running in one */ | |
787 | if (mount("proc", mount_entry_path(m), "proc", MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) < 0) | |
788 | return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m)); | |
789 | ||
790 | return 1; | |
791 | } | |
792 | ||
2abd4e38 | 793 | static int mount_tmpfs(const MountEntry *m) { |
6c47cd7d LP |
794 | assert(m); |
795 | ||
2abd4e38 | 796 | /* First, get rid of everything that is below if there is anything. Then, overmount with our new tmpfs */ |
6c47cd7d LP |
797 | |
798 | (void) mkdir_p_label(mount_entry_path(m), 0755); | |
799 | (void) umount_recursive(mount_entry_path(m), 0); | |
800 | ||
2abd4e38 | 801 | if (mount("tmpfs", mount_entry_path(m), "tmpfs", m->flags, mount_entry_options(m)) < 0) |
6c47cd7d LP |
802 | return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m)); |
803 | ||
804 | return 1; | |
805 | } | |
806 | ||
d2d6c096 LP |
807 | static int mount_entry_chase( |
808 | const char *root_directory, | |
2a2969fd | 809 | const MountEntry *m, |
d2d6c096 | 810 | const char *path, |
4ca763a9 | 811 | bool chase_nonexistent, |
d2d6c096 LP |
812 | char **location) { |
813 | ||
8fceda93 LP |
814 | char *chased; |
815 | int r; | |
816 | ||
817 | assert(m); | |
818 | ||
819 | /* Since mount() will always follow symlinks and we need to take the different root directory into account we | |
d2d6c096 LP |
820 | * chase the symlinks on our own first. This is called for the destination path, as well as the source path (if |
821 | * that applies). The result is stored in "location". */ | |
8fceda93 | 822 | |
4ca763a9 | 823 | r = chase_symlinks(path, root_directory, chase_nonexistent ? CHASE_NONEXISTENT : 0, &chased); |
8fceda93 | 824 | if (r == -ENOENT && m->ignore) { |
d2d6c096 | 825 | log_debug_errno(r, "Path %s does not exist, ignoring.", path); |
8fceda93 LP |
826 | return 0; |
827 | } | |
828 | if (r < 0) | |
d2d6c096 | 829 | return log_debug_errno(r, "Failed to follow symlinks on %s: %m", path); |
8fceda93 | 830 | |
d2d6c096 | 831 | log_debug("Followed symlinks %s → %s.", path, chased); |
8fceda93 | 832 | |
d2d6c096 LP |
833 | free(*location); |
834 | *location = chased; | |
8fceda93 LP |
835 | |
836 | return 1; | |
837 | } | |
838 | ||
ac0930c8 | 839 | static int apply_mount( |
8fceda93 | 840 | const char *root_directory, |
89bd586c | 841 | MountEntry *m) { |
ac0930c8 | 842 | |
a227a4be | 843 | bool rbind = true, make = false; |
15ae422b | 844 | const char *what; |
15ae422b | 845 | int r; |
15ae422b | 846 | |
c17ec25e | 847 | assert(m); |
15ae422b | 848 | |
4ca763a9 | 849 | r = mount_entry_chase(root_directory, m, mount_entry_path(m), !IN_SET(m->mode, INACCESSIBLE, READONLY, READWRITE), &m->path_malloc); |
8fceda93 LP |
850 | if (r <= 0) |
851 | return r; | |
852 | ||
34de407a | 853 | log_debug("Applying namespace mount on %s", mount_entry_path(m)); |
fe3c2583 | 854 | |
c17ec25e | 855 | switch (m->mode) { |
15ae422b | 856 | |
160cfdbe LP |
857 | case INACCESSIBLE: { |
858 | struct stat target; | |
6d313367 LP |
859 | |
860 | /* First, get rid of everything that is below if there | |
861 | * is anything... Then, overmount it with an | |
c4b41707 | 862 | * inaccessible path. */ |
34de407a | 863 | (void) umount_recursive(mount_entry_path(m), 0); |
6d313367 | 864 | |
34de407a LP |
865 | if (lstat(mount_entry_path(m), &target) < 0) |
866 | return log_debug_errno(errno, "Failed to lstat() %s to determine what to mount over it: %m", mount_entry_path(m)); | |
15ae422b | 867 | |
c4b41707 | 868 | what = mode_to_inaccessible_node(target.st_mode); |
5fd7cf6f LP |
869 | if (!what) { |
870 | log_debug("File type not supported for inaccessible mounts. Note that symlinks are not allowed"); | |
c4b41707 AP |
871 | return -ELOOP; |
872 | } | |
873 | break; | |
160cfdbe | 874 | } |
fe3c2583 | 875 | |
15ae422b | 876 | case READONLY: |
15ae422b | 877 | case READWRITE: |
8fceda93 | 878 | r = path_is_mount_point(mount_entry_path(m), root_directory, 0); |
d944dc95 | 879 | if (r < 0) |
34de407a | 880 | return log_debug_errno(r, "Failed to determine whether %s is already a mount point: %m", mount_entry_path(m)); |
6b7c9f8b LP |
881 | if (r > 0) /* Nothing to do here, it is already a mount. We just later toggle the MS_RDONLY bit for the mount point if needed. */ |
882 | return 0; | |
6b7c9f8b | 883 | /* This isn't a mount point yet, let's make it one. */ |
34de407a | 884 | what = mount_entry_path(m); |
6b7c9f8b | 885 | break; |
15ae422b | 886 | |
d2d6c096 LP |
887 | case BIND_MOUNT: |
888 | rbind = false; | |
d2d6c096 | 889 | |
4831981d | 890 | _fallthrough_; |
d2d6c096 LP |
891 | case BIND_MOUNT_RECURSIVE: |
892 | /* Also chase the source mount */ | |
5d997827 | 893 | |
4ca763a9 | 894 | r = mount_entry_chase(root_directory, m, mount_entry_source(m), false, &m->source_malloc); |
d2d6c096 LP |
895 | if (r <= 0) |
896 | return r; | |
897 | ||
898 | what = mount_entry_source(m); | |
a227a4be | 899 | make = true; |
d2d6c096 LP |
900 | break; |
901 | ||
6c47cd7d | 902 | case EMPTY_DIR: |
2abd4e38 YW |
903 | case TMPFS: |
904 | return mount_tmpfs(m); | |
6c47cd7d | 905 | |
ac0930c8 | 906 | case PRIVATE_TMP: |
89bd586c | 907 | what = mount_entry_source(m); |
a227a4be | 908 | make = true; |
15ae422b | 909 | break; |
e364ad06 | 910 | |
d6797c92 | 911 | case PRIVATE_DEV: |
5d997827 LP |
912 | return mount_private_dev(m); |
913 | ||
914 | case BIND_DEV: | |
915 | return mount_bind_dev(m); | |
916 | ||
917 | case SYSFS: | |
918 | return mount_sysfs(m); | |
919 | ||
920 | case PROCFS: | |
921 | return mount_procfs(m); | |
d6797c92 | 922 | |
e364ad06 LP |
923 | default: |
924 | assert_not_reached("Unknown mode"); | |
15ae422b LP |
925 | } |
926 | ||
ac0930c8 | 927 | assert(what); |
15ae422b | 928 | |
a227a4be LP |
929 | if (mount(what, mount_entry_path(m), NULL, MS_BIND|(rbind ? MS_REC : 0), NULL) < 0) { |
930 | bool try_again = false; | |
931 | r = -errno; | |
932 | ||
933 | if (r == -ENOENT && make) { | |
934 | struct stat st; | |
935 | ||
936 | /* Hmm, either the source or the destination are missing. Let's see if we can create the destination, then try again */ | |
937 | ||
938 | if (stat(what, &st) >= 0) { | |
939 | ||
940 | (void) mkdir_parents(mount_entry_path(m), 0755); | |
941 | ||
942 | if (S_ISDIR(st.st_mode)) | |
943 | try_again = mkdir(mount_entry_path(m), 0755) >= 0; | |
944 | else | |
945 | try_again = touch(mount_entry_path(m)) >= 0; | |
946 | } | |
947 | } | |
948 | ||
949 | if (try_again) { | |
950 | if (mount(what, mount_entry_path(m), NULL, MS_BIND|(rbind ? MS_REC : 0), NULL) < 0) | |
951 | r = -errno; | |
952 | else | |
953 | r = 0; | |
954 | } | |
955 | ||
956 | if (r < 0) | |
957 | return log_debug_errno(r, "Failed to mount %s to %s: %m", what, mount_entry_path(m)); | |
958 | } | |
6b7c9f8b | 959 | |
34de407a | 960 | log_debug("Successfully mounted %s to %s", what, mount_entry_path(m)); |
6b7c9f8b | 961 | return 0; |
ac0930c8 | 962 | } |
15ae422b | 963 | |
2a2969fd | 964 | static int make_read_only(const MountEntry *m, char **blacklist, FILE *proc_self_mountinfo) { |
6b7c9f8b | 965 | int r = 0; |
15ae422b | 966 | |
c17ec25e | 967 | assert(m); |
ac9de0b3 | 968 | assert(proc_self_mountinfo); |
ac0930c8 | 969 | |
2abd4e38 YW |
970 | if (mount_entry_read_only(m)) { |
971 | if (IN_SET(m->mode, EMPTY_DIR, TMPFS)) { | |
972 | /* Make superblock readonly */ | |
973 | if (mount(NULL, mount_entry_path(m), NULL, MS_REMOUNT | MS_RDONLY | m->flags, mount_entry_options(m)) < 0) | |
974 | r = -errno; | |
975 | } else | |
976 | r = bind_remount_recursive_with_mountinfo(mount_entry_path(m), true, blacklist, proc_self_mountinfo); | |
977 | } else if (m->mode == PRIVATE_DEV) { | |
978 | /* Superblock can be readonly but the submounts can't */ | |
34de407a | 979 | if (mount(NULL, mount_entry_path(m), NULL, MS_REMOUNT|DEV_MOUNT_OPTIONS|MS_RDONLY, NULL) < 0) |
6b7c9f8b | 980 | r = -errno; |
737ba3c8 | 981 | } else |
6b7c9f8b LP |
982 | return 0; |
983 | ||
984 | /* Not that we only turn on the MS_RDONLY flag here, we never turn it off. Something that was marked read-only | |
985 | * already stays this way. This improves compatibility with container managers, where we won't attempt to undo | |
986 | * read-only mounts already applied. */ | |
ac0930c8 | 987 | |
8fceda93 LP |
988 | if (r == -ENOENT && m->ignore) |
989 | r = 0; | |
5327c910 | 990 | |
1d54cd5d | 991 | return r; |
d944dc95 LP |
992 | } |
993 | ||
bb0ff3fb | 994 | static bool namespace_info_mount_apivfs(const char *root_directory, const NamespaceInfo *ns_info) { |
5d997827 LP |
995 | assert(ns_info); |
996 | ||
9c988f93 DH |
997 | /* |
998 | * ProtectControlGroups= and ProtectKernelTunables= imply MountAPIVFS=, | |
999 | * since to protect the API VFS mounts, they need to be around in the | |
1000 | * first place... and RootDirectory= or RootImage= need to be set. | |
1001 | */ | |
5d997827 | 1002 | |
9c988f93 DH |
1003 | /* root_directory should point to a mount point */ |
1004 | return root_directory && | |
1005 | (ns_info->mount_apivfs || | |
1006 | ns_info->protect_control_groups || | |
1007 | ns_info->protect_kernel_tunables); | |
5d997827 LP |
1008 | } |
1009 | ||
2652c6c1 | 1010 | static unsigned namespace_calculate_mounts( |
9c988f93 | 1011 | const char* root_directory, |
bb0ff3fb | 1012 | const NamespaceInfo *ns_info, |
2652c6c1 DH |
1013 | char** read_write_paths, |
1014 | char** read_only_paths, | |
1015 | char** inaccessible_paths, | |
6c47cd7d | 1016 | char** empty_directories, |
d2d6c096 | 1017 | unsigned n_bind_mounts, |
2abd4e38 | 1018 | unsigned n_temporary_filesystems, |
2652c6c1 DH |
1019 | const char* tmp_dir, |
1020 | const char* var_tmp_dir, | |
2652c6c1 DH |
1021 | ProtectHome protect_home, |
1022 | ProtectSystem protect_system) { | |
1023 | ||
b6c432ca | 1024 | unsigned protect_home_cnt; |
f471b2af DH |
1025 | unsigned protect_system_cnt = |
1026 | (protect_system == PROTECT_SYSTEM_STRICT ? | |
1027 | ELEMENTSOF(protect_system_strict_table) : | |
1028 | ((protect_system == PROTECT_SYSTEM_FULL) ? | |
1029 | ELEMENTSOF(protect_system_full_table) : | |
1030 | ((protect_system == PROTECT_SYSTEM_YES) ? | |
1031 | ELEMENTSOF(protect_system_yes_table) : 0))); | |
1032 | ||
b6c432ca DH |
1033 | protect_home_cnt = |
1034 | (protect_home == PROTECT_HOME_YES ? | |
1035 | ELEMENTSOF(protect_home_yes_table) : | |
1036 | ((protect_home == PROTECT_HOME_READ_ONLY) ? | |
e4da7d8c YW |
1037 | ELEMENTSOF(protect_home_read_only_table) : |
1038 | ((protect_home == PROTECT_HOME_TMPFS) ? | |
1039 | ELEMENTSOF(protect_home_tmpfs_table) : 0))); | |
b6c432ca | 1040 | |
2652c6c1 DH |
1041 | return !!tmp_dir + !!var_tmp_dir + |
1042 | strv_length(read_write_paths) + | |
1043 | strv_length(read_only_paths) + | |
1044 | strv_length(inaccessible_paths) + | |
6c47cd7d | 1045 | strv_length(empty_directories) + |
d2d6c096 | 1046 | n_bind_mounts + |
2abd4e38 | 1047 | n_temporary_filesystems + |
c575770b DH |
1048 | ns_info->private_dev + |
1049 | (ns_info->protect_kernel_tunables ? ELEMENTSOF(protect_kernel_tunables_table) : 0) + | |
1050 | (ns_info->protect_control_groups ? 1 : 0) + | |
1051 | (ns_info->protect_kernel_modules ? ELEMENTSOF(protect_kernel_modules_table) : 0) + | |
5d997827 | 1052 | protect_home_cnt + protect_system_cnt + |
9c988f93 | 1053 | (namespace_info_mount_apivfs(root_directory, ns_info) ? ELEMENTSOF(apivfs_table) : 0); |
2652c6c1 DH |
1054 | } |
1055 | ||
613b411c | 1056 | int setup_namespace( |
ee818b89 | 1057 | const char* root_directory, |
915e6d16 | 1058 | const char* root_image, |
bb0ff3fb | 1059 | const NamespaceInfo *ns_info, |
2a624c36 AP |
1060 | char** read_write_paths, |
1061 | char** read_only_paths, | |
1062 | char** inaccessible_paths, | |
6c47cd7d | 1063 | char** empty_directories, |
d2d6c096 LP |
1064 | const BindMount *bind_mounts, |
1065 | unsigned n_bind_mounts, | |
2abd4e38 YW |
1066 | const TemporaryFileSystem *temporary_filesystems, |
1067 | unsigned n_temporary_filesystems, | |
a004cb4c LP |
1068 | const char* tmp_dir, |
1069 | const char* var_tmp_dir, | |
1b8689f9 LP |
1070 | ProtectHome protect_home, |
1071 | ProtectSystem protect_system, | |
915e6d16 LP |
1072 | unsigned long mount_flags, |
1073 | DissectImageFlags dissect_image_flags) { | |
15ae422b | 1074 | |
915e6d16 | 1075 | _cleanup_(loop_device_unrefp) LoopDevice *loop_device = NULL; |
78ebe980 | 1076 | _cleanup_(decrypted_image_unrefp) DecryptedImage *decrypted_image = NULL; |
915e6d16 | 1077 | _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL; |
78ebe980 | 1078 | _cleanup_free_ void *root_hash = NULL; |
34de407a | 1079 | MountEntry *m, *mounts = NULL; |
78ebe980 | 1080 | size_t root_hash_size = 0; |
d944dc95 | 1081 | bool make_slave = false; |
e908468b | 1082 | const char *root; |
f0a4feb0 | 1083 | unsigned n_mounts; |
d18aff04 | 1084 | bool require_prefix = false; |
c17ec25e | 1085 | int r = 0; |
15ae422b | 1086 | |
915e6d16 LP |
1087 | assert(ns_info); |
1088 | ||
613b411c | 1089 | if (mount_flags == 0) |
c17ec25e | 1090 | mount_flags = MS_SHARED; |
ac0930c8 | 1091 | |
915e6d16 LP |
1092 | if (root_image) { |
1093 | dissect_image_flags |= DISSECT_IMAGE_REQUIRE_ROOT; | |
1094 | ||
1095 | if (protect_system == PROTECT_SYSTEM_STRICT && strv_isempty(read_write_paths)) | |
1096 | dissect_image_flags |= DISSECT_IMAGE_READ_ONLY; | |
1097 | ||
1098 | r = loop_device_make_by_path(root_image, | |
1099 | dissect_image_flags & DISSECT_IMAGE_READ_ONLY ? O_RDONLY : O_RDWR, | |
1100 | &loop_device); | |
1101 | if (r < 0) | |
1102 | return r; | |
1103 | ||
78ebe980 LP |
1104 | r = root_hash_load(root_image, &root_hash, &root_hash_size); |
1105 | if (r < 0) | |
1106 | return r; | |
1107 | ||
1108 | r = dissect_image(loop_device->fd, root_hash, root_hash_size, dissect_image_flags, &dissected_image); | |
1109 | if (r < 0) | |
1110 | return r; | |
1111 | ||
1112 | r = dissected_image_decrypt(dissected_image, NULL, root_hash, root_hash_size, dissect_image_flags, &decrypted_image); | |
915e6d16 LP |
1113 | if (r < 0) |
1114 | return r; | |
915e6d16 LP |
1115 | } |
1116 | ||
e908468b LP |
1117 | if (root_directory) |
1118 | root = root_directory; | |
2abd4e38 | 1119 | else if (root_image || n_bind_mounts > 0 || n_temporary_filesystems > 0) { |
e908468b LP |
1120 | |
1121 | /* If we are booting from an image, create a mount point for the image, if it's still missing. We use | |
1122 | * the same mount point for all images, which is safe, since they all live in their own namespaces | |
1123 | * after all, and hence won't see each other. We also use such a root directory whenever there are bind | |
1124 | * mounts configured, so that their source mounts are never obstructed by mounts we already applied | |
1125 | * while we are applying them. */ | |
1126 | ||
1127 | root = "/run/systemd/unit-root"; | |
1128 | (void) mkdir_label(root, 0700); | |
d18aff04 | 1129 | require_prefix = true; |
e908468b LP |
1130 | } else |
1131 | root = NULL; | |
1132 | ||
cfbeb4ef | 1133 | n_mounts = namespace_calculate_mounts( |
e908468b | 1134 | root, |
cfbeb4ef LP |
1135 | ns_info, |
1136 | read_write_paths, | |
1137 | read_only_paths, | |
1138 | inaccessible_paths, | |
6c47cd7d | 1139 | empty_directories, |
f5c52a77 | 1140 | n_bind_mounts, |
2abd4e38 | 1141 | n_temporary_filesystems, |
cfbeb4ef LP |
1142 | tmp_dir, var_tmp_dir, |
1143 | protect_home, protect_system); | |
613b411c | 1144 | |
2652c6c1 | 1145 | /* Set mount slave mode */ |
e908468b | 1146 | if (root || n_mounts > 0) |
d944dc95 LP |
1147 | make_slave = true; |
1148 | ||
f0a4feb0 | 1149 | if (n_mounts > 0) { |
34de407a | 1150 | m = mounts = (MountEntry *) alloca0(n_mounts * sizeof(MountEntry)); |
d18aff04 | 1151 | r = append_access_mounts(&m, read_write_paths, READWRITE, require_prefix); |
613b411c | 1152 | if (r < 0) |
f0a4feb0 | 1153 | goto finish; |
613b411c | 1154 | |
d18aff04 | 1155 | r = append_access_mounts(&m, read_only_paths, READONLY, require_prefix); |
613b411c | 1156 | if (r < 0) |
f0a4feb0 | 1157 | goto finish; |
613b411c | 1158 | |
d18aff04 | 1159 | r = append_access_mounts(&m, inaccessible_paths, INACCESSIBLE, require_prefix); |
613b411c | 1160 | if (r < 0) |
f0a4feb0 | 1161 | goto finish; |
7ff7394d | 1162 | |
6c47cd7d LP |
1163 | r = append_empty_dir_mounts(&m, empty_directories); |
1164 | if (r < 0) | |
1165 | goto finish; | |
1166 | ||
d2d6c096 LP |
1167 | r = append_bind_mounts(&m, bind_mounts, n_bind_mounts); |
1168 | if (r < 0) | |
1169 | goto finish; | |
1170 | ||
2abd4e38 YW |
1171 | r = append_tmpfs_mounts(&m, temporary_filesystems, n_temporary_filesystems); |
1172 | if (r < 0) | |
1173 | goto finish; | |
1174 | ||
613b411c | 1175 | if (tmp_dir) { |
34de407a | 1176 | *(m++) = (MountEntry) { |
5327c910 LP |
1177 | .path_const = "/tmp", |
1178 | .mode = PRIVATE_TMP, | |
89bd586c | 1179 | .source_const = tmp_dir, |
5327c910 | 1180 | }; |
613b411c | 1181 | } |
7ff7394d | 1182 | |
613b411c | 1183 | if (var_tmp_dir) { |
34de407a | 1184 | *(m++) = (MountEntry) { |
5327c910 | 1185 | .path_const = "/var/tmp", |
89bd586c YW |
1186 | .mode = PRIVATE_TMP, |
1187 | .source_const = var_tmp_dir, | |
5327c910 | 1188 | }; |
7ff7394d | 1189 | } |
ac0930c8 | 1190 | |
c575770b | 1191 | if (ns_info->private_dev) { |
34de407a | 1192 | *(m++) = (MountEntry) { |
5327c910 LP |
1193 | .path_const = "/dev", |
1194 | .mode = PRIVATE_DEV, | |
1195 | }; | |
7f112f50 LP |
1196 | } |
1197 | ||
c575770b | 1198 | if (ns_info->protect_kernel_tunables) { |
5327c910 | 1199 | r = append_static_mounts(&m, protect_kernel_tunables_table, ELEMENTSOF(protect_kernel_tunables_table), ns_info->ignore_protect_paths); |
c575770b | 1200 | if (r < 0) |
f0a4feb0 | 1201 | goto finish; |
c575770b DH |
1202 | } |
1203 | ||
1204 | if (ns_info->protect_kernel_modules) { | |
5327c910 | 1205 | r = append_static_mounts(&m, protect_kernel_modules_table, ELEMENTSOF(protect_kernel_modules_table), ns_info->ignore_protect_paths); |
c575770b | 1206 | if (r < 0) |
f0a4feb0 | 1207 | goto finish; |
c575770b | 1208 | } |
59eeb84b | 1209 | |
c575770b | 1210 | if (ns_info->protect_control_groups) { |
34de407a | 1211 | *(m++) = (MountEntry) { |
5327c910 LP |
1212 | .path_const = "/sys/fs/cgroup", |
1213 | .mode = READONLY, | |
1214 | }; | |
59eeb84b LP |
1215 | } |
1216 | ||
5327c910 | 1217 | r = append_protect_home(&m, protect_home, ns_info->ignore_protect_paths); |
b6c432ca | 1218 | if (r < 0) |
f0a4feb0 | 1219 | goto finish; |
417116f2 | 1220 | |
5327c910 | 1221 | r = append_protect_system(&m, protect_system, false); |
f471b2af | 1222 | if (r < 0) |
f0a4feb0 | 1223 | goto finish; |
417116f2 | 1224 | |
e908468b | 1225 | if (namespace_info_mount_apivfs(root, ns_info)) { |
5d997827 LP |
1226 | r = append_static_mounts(&m, apivfs_table, ELEMENTSOF(apivfs_table), ns_info->ignore_protect_paths); |
1227 | if (r < 0) | |
1228 | goto finish; | |
1229 | } | |
1230 | ||
f0a4feb0 | 1231 | assert(mounts + n_mounts == m); |
ac0930c8 | 1232 | |
5327c910 | 1233 | /* Prepend the root directory where that's necessary */ |
e908468b | 1234 | r = prefix_where_needed(mounts, n_mounts, root); |
5327c910 LP |
1235 | if (r < 0) |
1236 | goto finish; | |
1237 | ||
34de407a | 1238 | qsort(mounts, n_mounts, sizeof(MountEntry), mount_path_compare); |
fe3c2583 | 1239 | |
f0a4feb0 | 1240 | drop_duplicates(mounts, &n_mounts); |
e908468b | 1241 | drop_outside_root(root, mounts, &n_mounts); |
f0a4feb0 DH |
1242 | drop_inaccessible(mounts, &n_mounts); |
1243 | drop_nop(mounts, &n_mounts); | |
15ae422b LP |
1244 | } |
1245 | ||
d944dc95 LP |
1246 | if (unshare(CLONE_NEWNS) < 0) { |
1247 | r = -errno; | |
1248 | goto finish; | |
1249 | } | |
1e4e94c8 | 1250 | |
d944dc95 | 1251 | if (make_slave) { |
c2c13f2d LP |
1252 | /* Remount / as SLAVE so that nothing now mounted in the namespace |
1253 | shows up in the parent */ | |
d944dc95 LP |
1254 | if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) { |
1255 | r = -errno; | |
1256 | goto finish; | |
1257 | } | |
ee818b89 AC |
1258 | } |
1259 | ||
915e6d16 | 1260 | if (root_image) { |
e908468b | 1261 | /* A root image is specified, mount it to the right place */ |
2d3a5a73 | 1262 | r = dissected_image_mount(dissected_image, root, UID_INVALID, dissect_image_flags); |
915e6d16 LP |
1263 | if (r < 0) |
1264 | goto finish; | |
1265 | ||
07ce7407 TM |
1266 | if (decrypted_image) { |
1267 | r = decrypted_image_relinquish(decrypted_image); | |
1268 | if (r < 0) | |
1269 | goto finish; | |
1270 | } | |
78ebe980 | 1271 | |
915e6d16 LP |
1272 | loop_device_relinquish(loop_device); |
1273 | ||
1274 | } else if (root_directory) { | |
1275 | ||
e908468b LP |
1276 | /* A root directory is specified. Turn its directory into bind mount, if it isn't one yet. */ |
1277 | r = path_is_mount_point(root, NULL, AT_SYMLINK_FOLLOW); | |
8f1ad200 | 1278 | if (r < 0) |
d944dc95 | 1279 | goto finish; |
8f1ad200 | 1280 | if (r == 0) { |
e908468b | 1281 | if (mount(root, root, NULL, MS_BIND|MS_REC, NULL) < 0) { |
8f1ad200 LP |
1282 | r = -errno; |
1283 | goto finish; | |
1284 | } | |
d944dc95 | 1285 | } |
e908468b LP |
1286 | |
1287 | } else if (root) { | |
1288 | ||
1289 | /* Let's mount the main root directory to the root directory to use */ | |
1290 | if (mount("/", root, NULL, MS_BIND|MS_REC, NULL) < 0) { | |
1291 | r = -errno; | |
1292 | goto finish; | |
1293 | } | |
ee818b89 | 1294 | } |
c2c13f2d | 1295 | |
4e0c20de LP |
1296 | /* Try to set up the new root directory before mounting anything else there. */ |
1297 | if (root_image || root_directory) | |
1298 | (void) base_filesystem_create(root, UID_INVALID, GID_INVALID); | |
1299 | ||
f0a4feb0 | 1300 | if (n_mounts > 0) { |
ac9de0b3 | 1301 | _cleanup_fclose_ FILE *proc_self_mountinfo = NULL; |
6b7c9f8b LP |
1302 | char **blacklist; |
1303 | unsigned j; | |
1304 | ||
ac9de0b3 TR |
1305 | /* Open /proc/self/mountinfo now as it may become unavailable if we mount anything on top of /proc. |
1306 | * For example, this is the case with the option: 'InaccessiblePaths=/proc' */ | |
1307 | proc_self_mountinfo = fopen("/proc/self/mountinfo", "re"); | |
1308 | if (!proc_self_mountinfo) { | |
1309 | r = -errno; | |
1310 | goto finish; | |
1311 | } | |
1312 | ||
6b7c9f8b | 1313 | /* First round, add in all special mounts we need */ |
f0a4feb0 | 1314 | for (m = mounts; m < mounts + n_mounts; ++m) { |
89bd586c | 1315 | r = apply_mount(root, m); |
c2c13f2d | 1316 | if (r < 0) |
d944dc95 | 1317 | goto finish; |
c2c13f2d | 1318 | } |
15ae422b | 1319 | |
6b7c9f8b | 1320 | /* Create a blacklist we can pass to bind_mount_recursive() */ |
f0a4feb0 DH |
1321 | blacklist = newa(char*, n_mounts+1); |
1322 | for (j = 0; j < n_mounts; j++) | |
34de407a | 1323 | blacklist[j] = (char*) mount_entry_path(mounts+j); |
6b7c9f8b LP |
1324 | blacklist[j] = NULL; |
1325 | ||
1326 | /* Second round, flip the ro bits if necessary. */ | |
f0a4feb0 | 1327 | for (m = mounts; m < mounts + n_mounts; ++m) { |
ac9de0b3 | 1328 | r = make_read_only(m, blacklist, proc_self_mountinfo); |
c2c13f2d | 1329 | if (r < 0) |
d944dc95 | 1330 | goto finish; |
c2c13f2d | 1331 | } |
15ae422b LP |
1332 | } |
1333 | ||
e908468b | 1334 | if (root) { |
ee818b89 | 1335 | /* MS_MOVE does not work on MS_SHARED so the remount MS_SHARED will be done later */ |
e908468b | 1336 | r = mount_move_root(root); |
d944dc95 LP |
1337 | if (r < 0) |
1338 | goto finish; | |
ee818b89 AC |
1339 | } |
1340 | ||
55fe7432 | 1341 | /* Remount / as the desired mode. Note that this will not |
c2c13f2d LP |
1342 | * reestablish propagation from our side to the host, since |
1343 | * what's disconnected is disconnected. */ | |
d944dc95 LP |
1344 | if (mount(NULL, "/", NULL, mount_flags | MS_REC, NULL) < 0) { |
1345 | r = -errno; | |
1346 | goto finish; | |
1347 | } | |
15ae422b | 1348 | |
d944dc95 | 1349 | r = 0; |
15ae422b | 1350 | |
d944dc95 | 1351 | finish: |
f0a4feb0 | 1352 | for (m = mounts; m < mounts + n_mounts; m++) |
1eb7e08e | 1353 | mount_entry_done(m); |
613b411c LP |
1354 | |
1355 | return r; | |
1356 | } | |
1357 | ||
d2d6c096 LP |
1358 | void bind_mount_free_many(BindMount *b, unsigned n) { |
1359 | unsigned i; | |
1360 | ||
1361 | assert(b || n == 0); | |
1362 | ||
1363 | for (i = 0; i < n; i++) { | |
1364 | free(b[i].source); | |
1365 | free(b[i].destination); | |
1366 | } | |
1367 | ||
1368 | free(b); | |
1369 | } | |
1370 | ||
1371 | int bind_mount_add(BindMount **b, unsigned *n, const BindMount *item) { | |
1372 | _cleanup_free_ char *s = NULL, *d = NULL; | |
1373 | BindMount *c; | |
1374 | ||
1375 | assert(b); | |
1376 | assert(n); | |
1377 | assert(item); | |
1378 | ||
1379 | s = strdup(item->source); | |
1380 | if (!s) | |
1381 | return -ENOMEM; | |
1382 | ||
1383 | d = strdup(item->destination); | |
1384 | if (!d) | |
1385 | return -ENOMEM; | |
1386 | ||
aa484f35 | 1387 | c = reallocarray(*b, *n + 1, sizeof(BindMount)); |
d2d6c096 LP |
1388 | if (!c) |
1389 | return -ENOMEM; | |
1390 | ||
1391 | *b = c; | |
1392 | ||
1393 | c[(*n) ++] = (BindMount) { | |
1394 | .source = s, | |
1395 | .destination = d, | |
1396 | .read_only = item->read_only, | |
1397 | .recursive = item->recursive, | |
1398 | .ignore_enoent = item->ignore_enoent, | |
1399 | }; | |
1400 | ||
1401 | s = d = NULL; | |
1402 | return 0; | |
1403 | } | |
1404 | ||
2abd4e38 YW |
1405 | void temporary_filesystem_free_many(TemporaryFileSystem *t, unsigned n) { |
1406 | unsigned i; | |
1407 | ||
1408 | assert(t || n == 0); | |
1409 | ||
1410 | for (i = 0; i < n; i++) { | |
1411 | free(t[i].path); | |
1412 | free(t[i].options); | |
1413 | } | |
1414 | ||
1415 | free(t); | |
1416 | } | |
1417 | ||
1418 | int temporary_filesystem_add( | |
1419 | TemporaryFileSystem **t, | |
1420 | unsigned *n, | |
1421 | const char *path, | |
1422 | const char *options) { | |
1423 | ||
1424 | _cleanup_free_ char *p = NULL, *o = NULL; | |
1425 | TemporaryFileSystem *c; | |
1426 | ||
1427 | assert(t); | |
1428 | assert(n); | |
1429 | assert(path); | |
1430 | ||
1431 | p = strdup(path); | |
1432 | if (!p) | |
1433 | return -ENOMEM; | |
1434 | ||
1435 | if (!isempty(options)) { | |
1436 | o = strdup(options); | |
1437 | if (!o) | |
1438 | return -ENOMEM; | |
1439 | } | |
1440 | ||
aa484f35 | 1441 | c = reallocarray(*t, *n + 1, sizeof(TemporaryFileSystem)); |
2abd4e38 YW |
1442 | if (!c) |
1443 | return -ENOMEM; | |
1444 | ||
1445 | *t = c; | |
1446 | ||
1447 | c[(*n) ++] = (TemporaryFileSystem) { | |
1448 | .path = p, | |
1449 | .options = o, | |
1450 | }; | |
1451 | ||
1452 | p = o = NULL; | |
1453 | return 0; | |
1454 | } | |
1455 | ||
613b411c LP |
1456 | static int setup_one_tmp_dir(const char *id, const char *prefix, char **path) { |
1457 | _cleanup_free_ char *x = NULL; | |
6b46ea73 LP |
1458 | char bid[SD_ID128_STRING_MAX]; |
1459 | sd_id128_t boot_id; | |
1460 | int r; | |
613b411c LP |
1461 | |
1462 | assert(id); | |
1463 | assert(prefix); | |
1464 | assert(path); | |
1465 | ||
6b46ea73 LP |
1466 | /* We include the boot id in the directory so that after a |
1467 | * reboot we can easily identify obsolete directories. */ | |
1468 | ||
1469 | r = sd_id128_get_boot(&boot_id); | |
1470 | if (r < 0) | |
1471 | return r; | |
1472 | ||
605405c6 | 1473 | x = strjoin(prefix, "/systemd-private-", sd_id128_to_string(boot_id, bid), "-", id, "-XXXXXX"); |
613b411c LP |
1474 | if (!x) |
1475 | return -ENOMEM; | |
1476 | ||
1477 | RUN_WITH_UMASK(0077) | |
1478 | if (!mkdtemp(x)) | |
1479 | return -errno; | |
1480 | ||
1481 | RUN_WITH_UMASK(0000) { | |
1482 | char *y; | |
1483 | ||
63c372cb | 1484 | y = strjoina(x, "/tmp"); |
613b411c LP |
1485 | |
1486 | if (mkdir(y, 0777 | S_ISVTX) < 0) | |
1487 | return -errno; | |
c17ec25e | 1488 | } |
15ae422b | 1489 | |
613b411c LP |
1490 | *path = x; |
1491 | x = NULL; | |
1492 | ||
1493 | return 0; | |
1494 | } | |
1495 | ||
1496 | int setup_tmp_dirs(const char *id, char **tmp_dir, char **var_tmp_dir) { | |
1497 | char *a, *b; | |
1498 | int r; | |
1499 | ||
1500 | assert(id); | |
1501 | assert(tmp_dir); | |
1502 | assert(var_tmp_dir); | |
1503 | ||
1504 | r = setup_one_tmp_dir(id, "/tmp", &a); | |
1505 | if (r < 0) | |
1506 | return r; | |
1507 | ||
1508 | r = setup_one_tmp_dir(id, "/var/tmp", &b); | |
1509 | if (r < 0) { | |
1510 | char *t; | |
1511 | ||
63c372cb | 1512 | t = strjoina(a, "/tmp"); |
613b411c LP |
1513 | rmdir(t); |
1514 | rmdir(a); | |
1515 | ||
1516 | free(a); | |
1517 | return r; | |
1518 | } | |
1519 | ||
1520 | *tmp_dir = a; | |
1521 | *var_tmp_dir = b; | |
1522 | ||
1523 | return 0; | |
1524 | } | |
1525 | ||
1526 | int setup_netns(int netns_storage_socket[2]) { | |
1527 | _cleanup_close_ int netns = -1; | |
3ee897d6 | 1528 | int r, q; |
613b411c LP |
1529 | |
1530 | assert(netns_storage_socket); | |
1531 | assert(netns_storage_socket[0] >= 0); | |
1532 | assert(netns_storage_socket[1] >= 0); | |
1533 | ||
1534 | /* We use the passed socketpair as a storage buffer for our | |
76cd584b LP |
1535 | * namespace reference fd. Whatever process runs this first |
1536 | * shall create a new namespace, all others should just join | |
1537 | * it. To serialize that we use a file lock on the socket | |
1538 | * pair. | |
613b411c LP |
1539 | * |
1540 | * It's a bit crazy, but hey, works great! */ | |
1541 | ||
1542 | if (lockf(netns_storage_socket[0], F_LOCK, 0) < 0) | |
1543 | return -errno; | |
1544 | ||
3ee897d6 LP |
1545 | netns = receive_one_fd(netns_storage_socket[0], MSG_DONTWAIT); |
1546 | if (netns == -EAGAIN) { | |
613b411c LP |
1547 | /* Nothing stored yet, so let's create a new namespace */ |
1548 | ||
1549 | if (unshare(CLONE_NEWNET) < 0) { | |
1550 | r = -errno; | |
1551 | goto fail; | |
1552 | } | |
1553 | ||
1554 | loopback_setup(); | |
1555 | ||
1556 | netns = open("/proc/self/ns/net", O_RDONLY|O_CLOEXEC|O_NOCTTY); | |
1557 | if (netns < 0) { | |
1558 | r = -errno; | |
1559 | goto fail; | |
1560 | } | |
1561 | ||
1562 | r = 1; | |
613b411c | 1563 | |
3ee897d6 LP |
1564 | } else if (netns < 0) { |
1565 | r = netns; | |
1566 | goto fail; | |
613b411c | 1567 | |
3ee897d6 LP |
1568 | } else { |
1569 | /* Yay, found something, so let's join the namespace */ | |
613b411c LP |
1570 | if (setns(netns, CLONE_NEWNET) < 0) { |
1571 | r = -errno; | |
1572 | goto fail; | |
1573 | } | |
1574 | ||
1575 | r = 0; | |
1576 | } | |
1577 | ||
3ee897d6 LP |
1578 | q = send_one_fd(netns_storage_socket[1], netns, MSG_DONTWAIT); |
1579 | if (q < 0) { | |
1580 | r = q; | |
613b411c LP |
1581 | goto fail; |
1582 | } | |
1583 | ||
1584 | fail: | |
fe048ce5 | 1585 | (void) lockf(netns_storage_socket[0], F_ULOCK, 0); |
15ae422b LP |
1586 | return r; |
1587 | } | |
417116f2 | 1588 | |
6e2d7c4f MS |
1589 | bool ns_type_supported(NamespaceType type) { |
1590 | const char *t, *ns_proc; | |
1591 | ||
0fa5b831 LP |
1592 | t = namespace_type_to_string(type); |
1593 | if (!t) /* Don't know how to translate this? Then it's not supported */ | |
6e2d7c4f MS |
1594 | return false; |
1595 | ||
6e2d7c4f | 1596 | ns_proc = strjoina("/proc/self/ns/", t); |
6e2d7c4f MS |
1597 | return access(ns_proc, F_OK) == 0; |
1598 | } | |
1599 | ||
1b8689f9 LP |
1600 | static const char *const protect_home_table[_PROTECT_HOME_MAX] = { |
1601 | [PROTECT_HOME_NO] = "no", | |
1602 | [PROTECT_HOME_YES] = "yes", | |
1603 | [PROTECT_HOME_READ_ONLY] = "read-only", | |
e4da7d8c | 1604 | [PROTECT_HOME_TMPFS] = "tmpfs", |
417116f2 LP |
1605 | }; |
1606 | ||
1b8689f9 LP |
1607 | DEFINE_STRING_TABLE_LOOKUP(protect_home, ProtectHome); |
1608 | ||
5e1c6154 YW |
1609 | ProtectHome parse_protect_home_or_bool(const char *s) { |
1610 | int r; | |
1611 | ||
1612 | r = parse_boolean(s); | |
1613 | if (r > 0) | |
1614 | return PROTECT_HOME_YES; | |
1615 | if (r == 0) | |
1616 | return PROTECT_HOME_NO; | |
1617 | ||
1618 | return protect_home_from_string(s); | |
1619 | } | |
1620 | ||
1b8689f9 LP |
1621 | static const char *const protect_system_table[_PROTECT_SYSTEM_MAX] = { |
1622 | [PROTECT_SYSTEM_NO] = "no", | |
1623 | [PROTECT_SYSTEM_YES] = "yes", | |
1624 | [PROTECT_SYSTEM_FULL] = "full", | |
3f815163 | 1625 | [PROTECT_SYSTEM_STRICT] = "strict", |
1b8689f9 LP |
1626 | }; |
1627 | ||
1628 | DEFINE_STRING_TABLE_LOOKUP(protect_system, ProtectSystem); | |
6e2d7c4f | 1629 | |
03c791aa YW |
1630 | ProtectSystem parse_protect_system_or_bool(const char *s) { |
1631 | int r; | |
1632 | ||
1633 | r = parse_boolean(s); | |
1634 | if (r > 0) | |
1635 | return PROTECT_SYSTEM_YES; | |
1636 | if (r == 0) | |
1637 | return PROTECT_SYSTEM_NO; | |
1638 | ||
1639 | return protect_system_from_string(s); | |
1640 | } | |
1641 | ||
6e2d7c4f MS |
1642 | static const char* const namespace_type_table[] = { |
1643 | [NAMESPACE_MOUNT] = "mnt", | |
1644 | [NAMESPACE_CGROUP] = "cgroup", | |
1645 | [NAMESPACE_UTS] = "uts", | |
1646 | [NAMESPACE_IPC] = "ipc", | |
1647 | [NAMESPACE_USER] = "user", | |
1648 | [NAMESPACE_PID] = "pid", | |
1649 | [NAMESPACE_NET] = "net", | |
1650 | }; | |
1651 | ||
1652 | DEFINE_STRING_TABLE_LOOKUP(namespace_type, NamespaceType); |