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Merge pull request #8199 from keszybz/small-things
[thirdparty/systemd.git] / src / nspawn / nspawn.c
1 /* SPDX-License-Identifier: LGPL-2.1+ */
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
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
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
15 Lesser General Public License for more details.
16
17 You should have received a copy of the GNU Lesser General Public License
18 along with systemd; If not, see <http://www.gnu.org/licenses/>.
19 ***/
20
21 #if HAVE_BLKID
22 #include <blkid.h>
23 #endif
24 #include <errno.h>
25 #include <getopt.h>
26 #include <grp.h>
27 #include <linux/loop.h>
28 #include <pwd.h>
29 #include <sched.h>
30 #if HAVE_SELINUX
31 #include <selinux/selinux.h>
32 #endif
33 #include <signal.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <sys/file.h>
38 #include <sys/mount.h>
39 #include <sys/personality.h>
40 #include <sys/prctl.h>
41 #include <sys/types.h>
42 #include <sys/wait.h>
43 #include <unistd.h>
44
45 #include "sd-bus.h"
46 #include "sd-daemon.h"
47 #include "sd-id128.h"
48
49 #include "alloc-util.h"
50 #include "barrier.h"
51 #include "base-filesystem.h"
52 #include "blkid-util.h"
53 #include "btrfs-util.h"
54 #include "bus-util.h"
55 #include "cap-list.h"
56 #include "capability-util.h"
57 #include "cgroup-util.h"
58 #include "copy.h"
59 #include "dev-setup.h"
60 #include "dissect-image.h"
61 #include "env-util.h"
62 #include "fd-util.h"
63 #include "fdset.h"
64 #include "fileio.h"
65 #include "format-util.h"
66 #include "fs-util.h"
67 #include "gpt.h"
68 #include "hexdecoct.h"
69 #include "hostname-util.h"
70 #include "id128-util.h"
71 #include "log.h"
72 #include "loop-util.h"
73 #include "loopback-setup.h"
74 #include "machine-image.h"
75 #include "macro.h"
76 #include "missing.h"
77 #include "mkdir.h"
78 #include "mount-util.h"
79 #include "netlink-util.h"
80 #include "nspawn-cgroup.h"
81 #include "nspawn-def.h"
82 #include "nspawn-expose-ports.h"
83 #include "nspawn-mount.h"
84 #include "nspawn-network.h"
85 #include "nspawn-patch-uid.h"
86 #include "nspawn-register.h"
87 #include "nspawn-seccomp.h"
88 #include "nspawn-settings.h"
89 #include "nspawn-setuid.h"
90 #include "nspawn-stub-pid1.h"
91 #include "parse-util.h"
92 #include "path-util.h"
93 #include "process-util.h"
94 #include "ptyfwd.h"
95 #include "random-util.h"
96 #include "raw-clone.h"
97 #include "rm-rf.h"
98 #include "selinux-util.h"
99 #include "signal-util.h"
100 #include "socket-util.h"
101 #include "stat-util.h"
102 #include "stdio-util.h"
103 #include "string-util.h"
104 #include "strv.h"
105 #include "terminal-util.h"
106 #include "udev-util.h"
107 #include "umask-util.h"
108 #include "user-util.h"
109 #include "util.h"
110
111 #if HAVE_SPLIT_USR
112 #define STATIC_RESOLV_CONF "/lib/systemd/resolv.conf"
113 #else
114 #define STATIC_RESOLV_CONF "/usr/lib/systemd/resolv.conf"
115 #endif
116
117 /* nspawn is listening on the socket at the path in the constant nspawn_notify_socket_path
118 * nspawn_notify_socket_path is relative to the container
119 * the init process in the container pid can send messages to nspawn following the sd_notify(3) protocol */
120 #define NSPAWN_NOTIFY_SOCKET_PATH "/run/systemd/nspawn/notify"
121
122 #define EXIT_FORCE_RESTART 133
123
124 typedef enum ContainerStatus {
125 CONTAINER_TERMINATED,
126 CONTAINER_REBOOTED
127 } ContainerStatus;
128
129 typedef enum LinkJournal {
130 LINK_NO,
131 LINK_AUTO,
132 LINK_HOST,
133 LINK_GUEST
134 } LinkJournal;
135
136 static char *arg_directory = NULL;
137 static char *arg_template = NULL;
138 static char *arg_chdir = NULL;
139 static char *arg_pivot_root_new = NULL;
140 static char *arg_pivot_root_old = NULL;
141 static char *arg_user = NULL;
142 static sd_id128_t arg_uuid = {};
143 static char *arg_machine = NULL;
144 static const char *arg_selinux_context = NULL;
145 static const char *arg_selinux_apifs_context = NULL;
146 static const char *arg_slice = NULL;
147 static bool arg_private_network = false;
148 static bool arg_read_only = false;
149 static StartMode arg_start_mode = START_PID1;
150 static bool arg_ephemeral = false;
151 static LinkJournal arg_link_journal = LINK_AUTO;
152 static bool arg_link_journal_try = false;
153 static uint64_t arg_caps_retain =
154 (1ULL << CAP_AUDIT_CONTROL) |
155 (1ULL << CAP_AUDIT_WRITE) |
156 (1ULL << CAP_CHOWN) |
157 (1ULL << CAP_DAC_OVERRIDE) |
158 (1ULL << CAP_DAC_READ_SEARCH) |
159 (1ULL << CAP_FOWNER) |
160 (1ULL << CAP_FSETID) |
161 (1ULL << CAP_IPC_OWNER) |
162 (1ULL << CAP_KILL) |
163 (1ULL << CAP_LEASE) |
164 (1ULL << CAP_LINUX_IMMUTABLE) |
165 (1ULL << CAP_MKNOD) |
166 (1ULL << CAP_NET_BIND_SERVICE) |
167 (1ULL << CAP_NET_BROADCAST) |
168 (1ULL << CAP_NET_RAW) |
169 (1ULL << CAP_SETFCAP) |
170 (1ULL << CAP_SETGID) |
171 (1ULL << CAP_SETPCAP) |
172 (1ULL << CAP_SETUID) |
173 (1ULL << CAP_SYS_ADMIN) |
174 (1ULL << CAP_SYS_BOOT) |
175 (1ULL << CAP_SYS_CHROOT) |
176 (1ULL << CAP_SYS_NICE) |
177 (1ULL << CAP_SYS_PTRACE) |
178 (1ULL << CAP_SYS_RESOURCE) |
179 (1ULL << CAP_SYS_TTY_CONFIG);
180 static CustomMount *arg_custom_mounts = NULL;
181 static unsigned arg_n_custom_mounts = 0;
182 static char **arg_setenv = NULL;
183 static bool arg_quiet = false;
184 static bool arg_register = true;
185 static bool arg_keep_unit = false;
186 static char **arg_network_interfaces = NULL;
187 static char **arg_network_macvlan = NULL;
188 static char **arg_network_ipvlan = NULL;
189 static bool arg_network_veth = false;
190 static char **arg_network_veth_extra = NULL;
191 static char *arg_network_bridge = NULL;
192 static char *arg_network_zone = NULL;
193 static char *arg_network_namespace_path = NULL;
194 static unsigned long arg_personality = PERSONALITY_INVALID;
195 static char *arg_image = NULL;
196 static VolatileMode arg_volatile_mode = VOLATILE_NO;
197 static ExposePort *arg_expose_ports = NULL;
198 static char **arg_property = NULL;
199 static UserNamespaceMode arg_userns_mode = USER_NAMESPACE_NO;
200 static uid_t arg_uid_shift = UID_INVALID, arg_uid_range = 0x10000U;
201 static bool arg_userns_chown = false;
202 static int arg_kill_signal = 0;
203 static CGroupUnified arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_UNKNOWN;
204 static SettingsMask arg_settings_mask = 0;
205 static int arg_settings_trusted = -1;
206 static char **arg_parameters = NULL;
207 static const char *arg_container_service_name = "systemd-nspawn";
208 static bool arg_notify_ready = false;
209 static bool arg_use_cgns = true;
210 static unsigned long arg_clone_ns_flags = CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS;
211 static MountSettingsMask arg_mount_settings = MOUNT_APPLY_APIVFS_RO;
212 static void *arg_root_hash = NULL;
213 static size_t arg_root_hash_size = 0;
214 static char **arg_syscall_whitelist = NULL;
215 static char **arg_syscall_blacklist = NULL;
216
217 static void help(void) {
218 printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
219 "Spawn a minimal namespace container for debugging, testing and building.\n\n"
220 " -h --help Show this help\n"
221 " --version Print version string\n"
222 " -q --quiet Do not show status information\n"
223 " -D --directory=PATH Root directory for the container\n"
224 " --template=PATH Initialize root directory from template directory,\n"
225 " if missing\n"
226 " -x --ephemeral Run container with snapshot of root directory, and\n"
227 " remove it after exit\n"
228 " -i --image=PATH File system device or disk image for the container\n"
229 " --root-hash=HASH Specify verity root hash\n"
230 " -a --as-pid2 Maintain a stub init as PID1, invoke binary as PID2\n"
231 " -b --boot Boot up full system (i.e. invoke init)\n"
232 " --chdir=PATH Set working directory in the container\n"
233 " --pivot-root=PATH[:PATH]\n"
234 " Pivot root to given directory in the container\n"
235 " -u --user=USER Run the command under specified user or uid\n"
236 " -M --machine=NAME Set the machine name for the container\n"
237 " --uuid=UUID Set a specific machine UUID for the container\n"
238 " -S --slice=SLICE Place the container in the specified slice\n"
239 " --property=NAME=VALUE Set scope unit property\n"
240 " -U --private-users=pick Run within user namespace, autoselect UID/GID range\n"
241 " --private-users[=UIDBASE[:NUIDS]]\n"
242 " Similar, but with user configured UID/GID range\n"
243 " --private-users-chown Adjust OS tree ownership to private UID/GID range\n"
244 " --private-network Disable network in container\n"
245 " --network-interface=INTERFACE\n"
246 " Assign an existing network interface to the\n"
247 " container\n"
248 " --network-macvlan=INTERFACE\n"
249 " Create a macvlan network interface based on an\n"
250 " existing network interface to the container\n"
251 " --network-ipvlan=INTERFACE\n"
252 " Create a ipvlan network interface based on an\n"
253 " existing network interface to the container\n"
254 " -n --network-veth Add a virtual Ethernet connection between host\n"
255 " and container\n"
256 " --network-veth-extra=HOSTIF[:CONTAINERIF]\n"
257 " Add an additional virtual Ethernet link between\n"
258 " host and container\n"
259 " --network-bridge=INTERFACE\n"
260 " Add a virtual Ethernet connection to the container\n"
261 " and attach it to an existing bridge on the host\n"
262 " --network-zone=NAME Similar, but attach the new interface to an\n"
263 " an automatically managed bridge interface\n"
264 " --network-namespace-path=PATH\n"
265 " Set network namespace to the one represented by\n"
266 " the specified kernel namespace file node\n"
267 " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n"
268 " Expose a container IP port on the host\n"
269 " -Z --selinux-context=SECLABEL\n"
270 " Set the SELinux security context to be used by\n"
271 " processes in the container\n"
272 " -L --selinux-apifs-context=SECLABEL\n"
273 " Set the SELinux security context to be used by\n"
274 " API/tmpfs file systems in the container\n"
275 " --capability=CAP In addition to the default, retain specified\n"
276 " capability\n"
277 " --drop-capability=CAP Drop the specified capability from the default set\n"
278 " --system-call-filter=LIST|~LIST\n"
279 " Permit/prohibit specific system calls\n"
280 " --kill-signal=SIGNAL Select signal to use for shutting down PID 1\n"
281 " --link-journal=MODE Link up guest journal, one of no, auto, guest, \n"
282 " host, try-guest, try-host\n"
283 " -j Equivalent to --link-journal=try-guest\n"
284 " --read-only Mount the root directory read-only\n"
285 " --bind=PATH[:PATH[:OPTIONS]]\n"
286 " Bind mount a file or directory from the host into\n"
287 " the container\n"
288 " --bind-ro=PATH[:PATH[:OPTIONS]\n"
289 " Similar, but creates a read-only bind mount\n"
290 " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n"
291 " --overlay=PATH[:PATH...]:PATH\n"
292 " Create an overlay mount from the host to \n"
293 " the container\n"
294 " --overlay-ro=PATH[:PATH...]:PATH\n"
295 " Similar, but creates a read-only overlay mount\n"
296 " -E --setenv=NAME=VALUE Pass an environment variable to PID 1\n"
297 " --register=BOOLEAN Register container as machine\n"
298 " --keep-unit Do not register a scope for the machine, reuse\n"
299 " the service unit nspawn is running in\n"
300 " --volatile[=MODE] Run the system in volatile mode\n"
301 " --settings=BOOLEAN Load additional settings from .nspawn file\n"
302 " --notify-ready=BOOLEAN Receive notifications from the child init process\n"
303 , program_invocation_short_name);
304 }
305
306 static int custom_mount_check_all(void) {
307 unsigned i;
308
309 for (i = 0; i < arg_n_custom_mounts; i++) {
310 CustomMount *m = &arg_custom_mounts[i];
311
312 if (path_equal(m->destination, "/") && arg_userns_mode != USER_NAMESPACE_NO) {
313
314 if (arg_userns_chown) {
315 log_error("--private-users-chown may not be combined with custom root mounts.");
316 return -EINVAL;
317 } else if (arg_uid_shift == UID_INVALID) {
318 log_error("--private-users with automatic UID shift may not be combined with custom root mounts.");
319 return -EINVAL;
320 }
321 }
322 }
323
324 return 0;
325 }
326
327 static int detect_unified_cgroup_hierarchy_from_environment(void) {
328 const char *e;
329 int r;
330
331 /* Allow the user to control whether the unified hierarchy is used */
332 e = getenv("UNIFIED_CGROUP_HIERARCHY");
333 if (e) {
334 r = parse_boolean(e);
335 if (r < 0)
336 return log_error_errno(r, "Failed to parse $UNIFIED_CGROUP_HIERARCHY.");
337 if (r > 0)
338 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
339 else
340 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
341 }
342
343 return 0;
344 }
345
346 static int detect_unified_cgroup_hierarchy_from_image(const char *directory) {
347 int r;
348
349 /* Let's inherit the mode to use from the host system, but let's take into consideration what systemd in the
350 * image actually supports. */
351 r = cg_all_unified();
352 if (r < 0)
353 return log_error_errno(r, "Failed to determine whether we are in all unified mode.");
354 if (r > 0) {
355 /* Unified cgroup hierarchy support was added in 230. Unfortunately the detection
356 * routine only detects 231, so we'll have a false negative here for 230. */
357 r = systemd_installation_has_version(directory, 230);
358 if (r < 0)
359 return log_error_errno(r, "Failed to determine systemd version in container: %m");
360 if (r > 0)
361 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
362 else
363 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
364 } else if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) > 0) {
365 /* Mixed cgroup hierarchy support was added in 233 */
366 r = systemd_installation_has_version(directory, 233);
367 if (r < 0)
368 return log_error_errno(r, "Failed to determine systemd version in container: %m");
369 if (r > 0)
370 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_SYSTEMD;
371 else
372 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
373 } else
374 arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
375
376 log_debug("Using %s hierarchy for container.",
377 arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_NONE ? "legacy" :
378 arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_SYSTEMD ? "hybrid" : "unified");
379
380 return 0;
381 }
382
383 static void parse_share_ns_env(const char *name, unsigned long ns_flag) {
384 int r;
385
386 r = getenv_bool(name);
387 if (r == -ENXIO)
388 return;
389 if (r < 0)
390 log_warning_errno(r, "Failed to parse %s from environment, defaulting to false.", name);
391 arg_clone_ns_flags = (arg_clone_ns_flags & ~ns_flag) | (r > 0 ? 0 : ns_flag);
392 }
393
394 static void parse_mount_settings_env(void) {
395 int r;
396 const char *e;
397
398 e = getenv("SYSTEMD_NSPAWN_API_VFS_WRITABLE");
399 if (!e)
400 return;
401
402 if (streq(e, "network")) {
403 arg_mount_settings |= MOUNT_APPLY_APIVFS_RO|MOUNT_APPLY_APIVFS_NETNS;
404 return;
405 }
406
407 r = parse_boolean(e);
408 if (r < 0) {
409 log_warning_errno(r, "Failed to parse SYSTEMD_NSPAWN_API_VFS_WRITABLE from environment, ignoring.");
410 return;
411 }
412
413 SET_FLAG(arg_mount_settings, MOUNT_APPLY_APIVFS_RO, r == 0);
414 SET_FLAG(arg_mount_settings, MOUNT_APPLY_APIVFS_NETNS, false);
415 }
416
417 static int parse_argv(int argc, char *argv[]) {
418
419 enum {
420 ARG_VERSION = 0x100,
421 ARG_PRIVATE_NETWORK,
422 ARG_UUID,
423 ARG_READ_ONLY,
424 ARG_CAPABILITY,
425 ARG_DROP_CAPABILITY,
426 ARG_LINK_JOURNAL,
427 ARG_BIND,
428 ARG_BIND_RO,
429 ARG_TMPFS,
430 ARG_OVERLAY,
431 ARG_OVERLAY_RO,
432 ARG_SHARE_SYSTEM,
433 ARG_REGISTER,
434 ARG_KEEP_UNIT,
435 ARG_NETWORK_INTERFACE,
436 ARG_NETWORK_MACVLAN,
437 ARG_NETWORK_IPVLAN,
438 ARG_NETWORK_BRIDGE,
439 ARG_NETWORK_ZONE,
440 ARG_NETWORK_VETH_EXTRA,
441 ARG_NETWORK_NAMESPACE_PATH,
442 ARG_PERSONALITY,
443 ARG_VOLATILE,
444 ARG_TEMPLATE,
445 ARG_PROPERTY,
446 ARG_PRIVATE_USERS,
447 ARG_KILL_SIGNAL,
448 ARG_SETTINGS,
449 ARG_CHDIR,
450 ARG_PIVOT_ROOT,
451 ARG_PRIVATE_USERS_CHOWN,
452 ARG_NOTIFY_READY,
453 ARG_ROOT_HASH,
454 ARG_SYSTEM_CALL_FILTER,
455 };
456
457 static const struct option options[] = {
458 { "help", no_argument, NULL, 'h' },
459 { "version", no_argument, NULL, ARG_VERSION },
460 { "directory", required_argument, NULL, 'D' },
461 { "template", required_argument, NULL, ARG_TEMPLATE },
462 { "ephemeral", no_argument, NULL, 'x' },
463 { "user", required_argument, NULL, 'u' },
464 { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK },
465 { "as-pid2", no_argument, NULL, 'a' },
466 { "boot", no_argument, NULL, 'b' },
467 { "uuid", required_argument, NULL, ARG_UUID },
468 { "read-only", no_argument, NULL, ARG_READ_ONLY },
469 { "capability", required_argument, NULL, ARG_CAPABILITY },
470 { "drop-capability", required_argument, NULL, ARG_DROP_CAPABILITY },
471 { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
472 { "bind", required_argument, NULL, ARG_BIND },
473 { "bind-ro", required_argument, NULL, ARG_BIND_RO },
474 { "tmpfs", required_argument, NULL, ARG_TMPFS },
475 { "overlay", required_argument, NULL, ARG_OVERLAY },
476 { "overlay-ro", required_argument, NULL, ARG_OVERLAY_RO },
477 { "machine", required_argument, NULL, 'M' },
478 { "slice", required_argument, NULL, 'S' },
479 { "setenv", required_argument, NULL, 'E' },
480 { "selinux-context", required_argument, NULL, 'Z' },
481 { "selinux-apifs-context", required_argument, NULL, 'L' },
482 { "quiet", no_argument, NULL, 'q' },
483 { "share-system", no_argument, NULL, ARG_SHARE_SYSTEM }, /* not documented */
484 { "register", required_argument, NULL, ARG_REGISTER },
485 { "keep-unit", no_argument, NULL, ARG_KEEP_UNIT },
486 { "network-interface", required_argument, NULL, ARG_NETWORK_INTERFACE },
487 { "network-macvlan", required_argument, NULL, ARG_NETWORK_MACVLAN },
488 { "network-ipvlan", required_argument, NULL, ARG_NETWORK_IPVLAN },
489 { "network-veth", no_argument, NULL, 'n' },
490 { "network-veth-extra", required_argument, NULL, ARG_NETWORK_VETH_EXTRA },
491 { "network-bridge", required_argument, NULL, ARG_NETWORK_BRIDGE },
492 { "network-zone", required_argument, NULL, ARG_NETWORK_ZONE },
493 { "network-namespace-path", required_argument, NULL, ARG_NETWORK_NAMESPACE_PATH },
494 { "personality", required_argument, NULL, ARG_PERSONALITY },
495 { "image", required_argument, NULL, 'i' },
496 { "volatile", optional_argument, NULL, ARG_VOLATILE },
497 { "port", required_argument, NULL, 'p' },
498 { "property", required_argument, NULL, ARG_PROPERTY },
499 { "private-users", optional_argument, NULL, ARG_PRIVATE_USERS },
500 { "private-users-chown", optional_argument, NULL, ARG_PRIVATE_USERS_CHOWN },
501 { "kill-signal", required_argument, NULL, ARG_KILL_SIGNAL },
502 { "settings", required_argument, NULL, ARG_SETTINGS },
503 { "chdir", required_argument, NULL, ARG_CHDIR },
504 { "pivot-root", required_argument, NULL, ARG_PIVOT_ROOT },
505 { "notify-ready", required_argument, NULL, ARG_NOTIFY_READY },
506 { "root-hash", required_argument, NULL, ARG_ROOT_HASH },
507 { "system-call-filter", required_argument, NULL, ARG_SYSTEM_CALL_FILTER },
508 {}
509 };
510
511 int c, r;
512 const char *p, *e;
513 uint64_t plus = 0, minus = 0;
514 bool mask_all_settings = false, mask_no_settings = false;
515
516 assert(argc >= 0);
517 assert(argv);
518
519 while ((c = getopt_long(argc, argv, "+hD:u:abL:M:jS:Z:qi:xp:nUE:", options, NULL)) >= 0)
520
521 switch (c) {
522
523 case 'h':
524 help();
525 return 0;
526
527 case ARG_VERSION:
528 return version();
529
530 case 'D':
531 r = parse_path_argument_and_warn(optarg, false, &arg_directory);
532 if (r < 0)
533 return r;
534 break;
535
536 case ARG_TEMPLATE:
537 r = parse_path_argument_and_warn(optarg, false, &arg_template);
538 if (r < 0)
539 return r;
540 break;
541
542 case 'i':
543 r = parse_path_argument_and_warn(optarg, false, &arg_image);
544 if (r < 0)
545 return r;
546 break;
547
548 case 'x':
549 arg_ephemeral = true;
550 break;
551
552 case 'u':
553 r = free_and_strdup(&arg_user, optarg);
554 if (r < 0)
555 return log_oom();
556
557 arg_settings_mask |= SETTING_USER;
558 break;
559
560 case ARG_NETWORK_ZONE: {
561 char *j;
562
563 j = strappend("vz-", optarg);
564 if (!j)
565 return log_oom();
566
567 if (!ifname_valid(j)) {
568 log_error("Network zone name not valid: %s", j);
569 free(j);
570 return -EINVAL;
571 }
572
573 free(arg_network_zone);
574 arg_network_zone = j;
575
576 arg_network_veth = true;
577 arg_private_network = true;
578 arg_settings_mask |= SETTING_NETWORK;
579 break;
580 }
581
582 case ARG_NETWORK_BRIDGE:
583
584 if (!ifname_valid(optarg)) {
585 log_error("Bridge interface name not valid: %s", optarg);
586 return -EINVAL;
587 }
588
589 r = free_and_strdup(&arg_network_bridge, optarg);
590 if (r < 0)
591 return log_oom();
592
593 _fallthrough_;
594 case 'n':
595 arg_network_veth = true;
596 arg_private_network = true;
597 arg_settings_mask |= SETTING_NETWORK;
598 break;
599
600 case ARG_NETWORK_VETH_EXTRA:
601 r = veth_extra_parse(&arg_network_veth_extra, optarg);
602 if (r < 0)
603 return log_error_errno(r, "Failed to parse --network-veth-extra= parameter: %s", optarg);
604
605 arg_private_network = true;
606 arg_settings_mask |= SETTING_NETWORK;
607 break;
608
609 case ARG_NETWORK_INTERFACE:
610
611 if (!ifname_valid(optarg)) {
612 log_error("Network interface name not valid: %s", optarg);
613 return -EINVAL;
614 }
615
616 if (strv_extend(&arg_network_interfaces, optarg) < 0)
617 return log_oom();
618
619 arg_private_network = true;
620 arg_settings_mask |= SETTING_NETWORK;
621 break;
622
623 case ARG_NETWORK_MACVLAN:
624
625 if (!ifname_valid(optarg)) {
626 log_error("MACVLAN network interface name not valid: %s", optarg);
627 return -EINVAL;
628 }
629
630 if (strv_extend(&arg_network_macvlan, optarg) < 0)
631 return log_oom();
632
633 arg_private_network = true;
634 arg_settings_mask |= SETTING_NETWORK;
635 break;
636
637 case ARG_NETWORK_IPVLAN:
638
639 if (!ifname_valid(optarg)) {
640 log_error("IPVLAN network interface name not valid: %s", optarg);
641 return -EINVAL;
642 }
643
644 if (strv_extend(&arg_network_ipvlan, optarg) < 0)
645 return log_oom();
646
647 _fallthrough_;
648 case ARG_PRIVATE_NETWORK:
649 arg_private_network = true;
650 arg_settings_mask |= SETTING_NETWORK;
651 break;
652
653 case ARG_NETWORK_NAMESPACE_PATH:
654 r = parse_path_argument_and_warn(optarg, false, &arg_network_namespace_path);
655 if (r < 0)
656 return r;
657
658 break;
659
660 case 'b':
661 if (arg_start_mode == START_PID2) {
662 log_error("--boot and --as-pid2 may not be combined.");
663 return -EINVAL;
664 }
665
666 arg_start_mode = START_BOOT;
667 arg_settings_mask |= SETTING_START_MODE;
668 break;
669
670 case 'a':
671 if (arg_start_mode == START_BOOT) {
672 log_error("--boot and --as-pid2 may not be combined.");
673 return -EINVAL;
674 }
675
676 arg_start_mode = START_PID2;
677 arg_settings_mask |= SETTING_START_MODE;
678 break;
679
680 case ARG_UUID:
681 r = sd_id128_from_string(optarg, &arg_uuid);
682 if (r < 0)
683 return log_error_errno(r, "Invalid UUID: %s", optarg);
684
685 if (sd_id128_is_null(arg_uuid)) {
686 log_error("Machine UUID may not be all zeroes.");
687 return -EINVAL;
688 }
689
690 arg_settings_mask |= SETTING_MACHINE_ID;
691 break;
692
693 case 'S':
694 arg_slice = optarg;
695 break;
696
697 case 'M':
698 if (isempty(optarg))
699 arg_machine = mfree(arg_machine);
700 else {
701 if (!machine_name_is_valid(optarg)) {
702 log_error("Invalid machine name: %s", optarg);
703 return -EINVAL;
704 }
705
706 r = free_and_strdup(&arg_machine, optarg);
707 if (r < 0)
708 return log_oom();
709 }
710 break;
711
712 case 'Z':
713 arg_selinux_context = optarg;
714 break;
715
716 case 'L':
717 arg_selinux_apifs_context = optarg;
718 break;
719
720 case ARG_READ_ONLY:
721 arg_read_only = true;
722 arg_settings_mask |= SETTING_READ_ONLY;
723 break;
724
725 case ARG_CAPABILITY:
726 case ARG_DROP_CAPABILITY: {
727 p = optarg;
728 for (;;) {
729 _cleanup_free_ char *t = NULL;
730
731 r = extract_first_word(&p, &t, ",", 0);
732 if (r < 0)
733 return log_error_errno(r, "Failed to parse capability %s.", t);
734
735 if (r == 0)
736 break;
737
738 if (streq(t, "all")) {
739 if (c == ARG_CAPABILITY)
740 plus = (uint64_t) -1;
741 else
742 minus = (uint64_t) -1;
743 } else {
744 int cap;
745
746 cap = capability_from_name(t);
747 if (cap < 0) {
748 log_error("Failed to parse capability %s.", t);
749 return -EINVAL;
750 }
751
752 if (c == ARG_CAPABILITY)
753 plus |= 1ULL << (uint64_t) cap;
754 else
755 minus |= 1ULL << (uint64_t) cap;
756 }
757 }
758
759 arg_settings_mask |= SETTING_CAPABILITY;
760 break;
761 }
762
763 case 'j':
764 arg_link_journal = LINK_GUEST;
765 arg_link_journal_try = true;
766 break;
767
768 case ARG_LINK_JOURNAL:
769 if (streq(optarg, "auto")) {
770 arg_link_journal = LINK_AUTO;
771 arg_link_journal_try = false;
772 } else if (streq(optarg, "no")) {
773 arg_link_journal = LINK_NO;
774 arg_link_journal_try = false;
775 } else if (streq(optarg, "guest")) {
776 arg_link_journal = LINK_GUEST;
777 arg_link_journal_try = false;
778 } else if (streq(optarg, "host")) {
779 arg_link_journal = LINK_HOST;
780 arg_link_journal_try = false;
781 } else if (streq(optarg, "try-guest")) {
782 arg_link_journal = LINK_GUEST;
783 arg_link_journal_try = true;
784 } else if (streq(optarg, "try-host")) {
785 arg_link_journal = LINK_HOST;
786 arg_link_journal_try = true;
787 } else {
788 log_error("Failed to parse link journal mode %s", optarg);
789 return -EINVAL;
790 }
791
792 break;
793
794 case ARG_BIND:
795 case ARG_BIND_RO:
796 r = bind_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg, c == ARG_BIND_RO);
797 if (r < 0)
798 return log_error_errno(r, "Failed to parse --bind(-ro)= argument %s: %m", optarg);
799
800 arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
801 break;
802
803 case ARG_TMPFS:
804 r = tmpfs_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg);
805 if (r < 0)
806 return log_error_errno(r, "Failed to parse --tmpfs= argument %s: %m", optarg);
807
808 arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
809 break;
810
811 case ARG_OVERLAY:
812 case ARG_OVERLAY_RO:
813 r = overlay_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg, c == ARG_OVERLAY_RO);
814 if (r == -EADDRNOTAVAIL)
815 return log_error_errno(r, "--overlay(-ro)= needs at least two colon-separated directories specified.");
816 if (r < 0)
817 return log_error_errno(r, "Failed to parse --overlay(-ro)= argument %s: %m", optarg);
818
819 arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
820 break;
821
822 case 'E': {
823 char **n;
824
825 if (!env_assignment_is_valid(optarg)) {
826 log_error("Environment variable assignment '%s' is not valid.", optarg);
827 return -EINVAL;
828 }
829
830 n = strv_env_set(arg_setenv, optarg);
831 if (!n)
832 return log_oom();
833
834 strv_free(arg_setenv);
835 arg_setenv = n;
836
837 arg_settings_mask |= SETTING_ENVIRONMENT;
838 break;
839 }
840
841 case 'q':
842 arg_quiet = true;
843 break;
844
845 case ARG_SHARE_SYSTEM:
846 /* We don't officially support this anymore, except for compat reasons. People should use the
847 * $SYSTEMD_NSPAWN_SHARE_* environment variables instead. */
848 arg_clone_ns_flags = 0;
849 break;
850
851 case ARG_REGISTER:
852 r = parse_boolean(optarg);
853 if (r < 0) {
854 log_error("Failed to parse --register= argument: %s", optarg);
855 return r;
856 }
857
858 arg_register = r;
859 break;
860
861 case ARG_KEEP_UNIT:
862 arg_keep_unit = true;
863 break;
864
865 case ARG_PERSONALITY:
866
867 arg_personality = personality_from_string(optarg);
868 if (arg_personality == PERSONALITY_INVALID) {
869 log_error("Unknown or unsupported personality '%s'.", optarg);
870 return -EINVAL;
871 }
872
873 arg_settings_mask |= SETTING_PERSONALITY;
874 break;
875
876 case ARG_VOLATILE:
877
878 if (!optarg)
879 arg_volatile_mode = VOLATILE_YES;
880 else {
881 VolatileMode m;
882
883 m = volatile_mode_from_string(optarg);
884 if (m < 0) {
885 log_error("Failed to parse --volatile= argument: %s", optarg);
886 return -EINVAL;
887 } else
888 arg_volatile_mode = m;
889 }
890
891 arg_settings_mask |= SETTING_VOLATILE_MODE;
892 break;
893
894 case 'p':
895 r = expose_port_parse(&arg_expose_ports, optarg);
896 if (r == -EEXIST)
897 return log_error_errno(r, "Duplicate port specification: %s", optarg);
898 if (r < 0)
899 return log_error_errno(r, "Failed to parse host port %s: %m", optarg);
900
901 arg_settings_mask |= SETTING_EXPOSE_PORTS;
902 break;
903
904 case ARG_PROPERTY:
905 if (strv_extend(&arg_property, optarg) < 0)
906 return log_oom();
907
908 break;
909
910 case ARG_PRIVATE_USERS: {
911 int boolean = -1;
912
913 if (!optarg)
914 boolean = true;
915 else if (!in_charset(optarg, DIGITS))
916 /* do *not* parse numbers as booleans */
917 boolean = parse_boolean(optarg);
918
919 if (boolean == false) {
920 /* no: User namespacing off */
921 arg_userns_mode = USER_NAMESPACE_NO;
922 arg_uid_shift = UID_INVALID;
923 arg_uid_range = UINT32_C(0x10000);
924 } else if (boolean == true) {
925 /* yes: User namespacing on, UID range is read from root dir */
926 arg_userns_mode = USER_NAMESPACE_FIXED;
927 arg_uid_shift = UID_INVALID;
928 arg_uid_range = UINT32_C(0x10000);
929 } else if (streq(optarg, "pick")) {
930 /* pick: User namespacing on, UID range is picked randomly */
931 arg_userns_mode = USER_NAMESPACE_PICK;
932 arg_uid_shift = UID_INVALID;
933 arg_uid_range = UINT32_C(0x10000);
934 } else {
935 _cleanup_free_ char *buffer = NULL;
936 const char *range, *shift;
937
938 /* anything else: User namespacing on, UID range is explicitly configured */
939
940 range = strchr(optarg, ':');
941 if (range) {
942 buffer = strndup(optarg, range - optarg);
943 if (!buffer)
944 return log_oom();
945 shift = buffer;
946
947 range++;
948 r = safe_atou32(range, &arg_uid_range);
949 if (r < 0)
950 return log_error_errno(r, "Failed to parse UID range \"%s\": %m", range);
951 } else
952 shift = optarg;
953
954 r = parse_uid(shift, &arg_uid_shift);
955 if (r < 0)
956 return log_error_errno(r, "Failed to parse UID \"%s\": %m", optarg);
957
958 arg_userns_mode = USER_NAMESPACE_FIXED;
959 }
960
961 if (arg_uid_range <= 0) {
962 log_error("UID range cannot be 0.");
963 return -EINVAL;
964 }
965
966 arg_settings_mask |= SETTING_USERNS;
967 break;
968 }
969
970 case 'U':
971 if (userns_supported()) {
972 arg_userns_mode = USER_NAMESPACE_PICK;
973 arg_uid_shift = UID_INVALID;
974 arg_uid_range = UINT32_C(0x10000);
975
976 arg_settings_mask |= SETTING_USERNS;
977 }
978
979 break;
980
981 case ARG_PRIVATE_USERS_CHOWN:
982 arg_userns_chown = true;
983
984 arg_settings_mask |= SETTING_USERNS;
985 break;
986
987 case ARG_KILL_SIGNAL:
988 arg_kill_signal = signal_from_string_try_harder(optarg);
989 if (arg_kill_signal < 0) {
990 log_error("Cannot parse signal: %s", optarg);
991 return -EINVAL;
992 }
993
994 arg_settings_mask |= SETTING_KILL_SIGNAL;
995 break;
996
997 case ARG_SETTINGS:
998
999 /* no → do not read files
1000 * yes → read files, do not override cmdline, trust only subset
1001 * override → read files, override cmdline, trust only subset
1002 * trusted → read files, do not override cmdline, trust all
1003 */
1004
1005 r = parse_boolean(optarg);
1006 if (r < 0) {
1007 if (streq(optarg, "trusted")) {
1008 mask_all_settings = false;
1009 mask_no_settings = false;
1010 arg_settings_trusted = true;
1011
1012 } else if (streq(optarg, "override")) {
1013 mask_all_settings = false;
1014 mask_no_settings = true;
1015 arg_settings_trusted = -1;
1016 } else
1017 return log_error_errno(r, "Failed to parse --settings= argument: %s", optarg);
1018 } else if (r > 0) {
1019 /* yes */
1020 mask_all_settings = false;
1021 mask_no_settings = false;
1022 arg_settings_trusted = -1;
1023 } else {
1024 /* no */
1025 mask_all_settings = true;
1026 mask_no_settings = false;
1027 arg_settings_trusted = false;
1028 }
1029
1030 break;
1031
1032 case ARG_CHDIR:
1033 if (!path_is_absolute(optarg)) {
1034 log_error("Working directory %s is not an absolute path.", optarg);
1035 return -EINVAL;
1036 }
1037
1038 r = free_and_strdup(&arg_chdir, optarg);
1039 if (r < 0)
1040 return log_oom();
1041
1042 arg_settings_mask |= SETTING_WORKING_DIRECTORY;
1043 break;
1044
1045 case ARG_PIVOT_ROOT:
1046 r = pivot_root_parse(&arg_pivot_root_new, &arg_pivot_root_old, optarg);
1047 if (r < 0)
1048 return log_error_errno(r, "Failed to parse --pivot-root= argument %s: %m", optarg);
1049
1050 arg_settings_mask |= SETTING_PIVOT_ROOT;
1051 break;
1052
1053 case ARG_NOTIFY_READY:
1054 r = parse_boolean(optarg);
1055 if (r < 0) {
1056 log_error("%s is not a valid notify mode. Valid modes are: yes, no, and ready.", optarg);
1057 return -EINVAL;
1058 }
1059 arg_notify_ready = r;
1060 arg_settings_mask |= SETTING_NOTIFY_READY;
1061 break;
1062
1063 case ARG_ROOT_HASH: {
1064 void *k;
1065 size_t l;
1066
1067 r = unhexmem(optarg, strlen(optarg), &k, &l);
1068 if (r < 0)
1069 return log_error_errno(r, "Failed to parse root hash: %s", optarg);
1070 if (l < sizeof(sd_id128_t)) {
1071 log_error("Root hash must be at least 128bit long: %s", optarg);
1072 free(k);
1073 return -EINVAL;
1074 }
1075
1076 free(arg_root_hash);
1077 arg_root_hash = k;
1078 arg_root_hash_size = l;
1079 break;
1080 }
1081
1082 case ARG_SYSTEM_CALL_FILTER: {
1083 bool negative;
1084 const char *items;
1085
1086 negative = optarg[0] == '~';
1087 items = negative ? optarg + 1 : optarg;
1088
1089 for (;;) {
1090 _cleanup_free_ char *word = NULL;
1091
1092 r = extract_first_word(&items, &word, NULL, 0);
1093 if (r == 0)
1094 break;
1095 if (r == -ENOMEM)
1096 return log_oom();
1097 if (r < 0)
1098 return log_error_errno(r, "Failed to parse system call filter: %m");
1099
1100 if (negative)
1101 r = strv_extend(&arg_syscall_blacklist, word);
1102 else
1103 r = strv_extend(&arg_syscall_whitelist, word);
1104 if (r < 0)
1105 return log_oom();
1106 }
1107
1108 arg_settings_mask |= SETTING_SYSCALL_FILTER;
1109 break;
1110 }
1111
1112 case '?':
1113 return -EINVAL;
1114
1115 default:
1116 assert_not_reached("Unhandled option");
1117 }
1118
1119 /* If --network-namespace-path is given with any other network-related option,
1120 * we need to error out, to avoid conflicts between different network options. */
1121 if (arg_network_namespace_path &&
1122 (arg_network_interfaces || arg_network_macvlan ||
1123 arg_network_ipvlan || arg_network_veth_extra ||
1124 arg_network_bridge || arg_network_zone ||
1125 arg_network_veth || arg_private_network)) {
1126 log_error("--network-namespace-path cannot be combined with other network options.");
1127 return -EINVAL;
1128 }
1129
1130 parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_IPC", CLONE_NEWIPC);
1131 parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_PID", CLONE_NEWPID);
1132 parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_UTS", CLONE_NEWUTS);
1133 parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_SYSTEM", CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS);
1134
1135 if (arg_userns_mode != USER_NAMESPACE_NO)
1136 arg_mount_settings |= MOUNT_USE_USERNS;
1137
1138 if (arg_private_network)
1139 arg_mount_settings |= MOUNT_APPLY_APIVFS_NETNS;
1140
1141 parse_mount_settings_env();
1142
1143 if (!(arg_clone_ns_flags & CLONE_NEWPID) ||
1144 !(arg_clone_ns_flags & CLONE_NEWUTS)) {
1145 arg_register = false;
1146 if (arg_start_mode != START_PID1) {
1147 log_error("--boot cannot be used without namespacing.");
1148 return -EINVAL;
1149 }
1150 }
1151
1152 if (arg_userns_mode == USER_NAMESPACE_PICK)
1153 arg_userns_chown = true;
1154
1155 if (arg_keep_unit && arg_register && cg_pid_get_owner_uid(0, NULL) >= 0) {
1156 /* Save the user from accidentally registering either user-$SESSION.scope or user@.service.
1157 * The latter is not technically a user session, but we don't need to labour the point. */
1158 log_error("--keep-unit --register=yes may not be used when invoked from a user session.");
1159 return -EINVAL;
1160 }
1161
1162 if (arg_directory && arg_image) {
1163 log_error("--directory= and --image= may not be combined.");
1164 return -EINVAL;
1165 }
1166
1167 if (arg_template && arg_image) {
1168 log_error("--template= and --image= may not be combined.");
1169 return -EINVAL;
1170 }
1171
1172 if (arg_ephemeral && arg_template && !arg_directory) {
1173 /* User asked for ephemeral execution but specified --template= instead of --directory=. Semantically
1174 * such an invocation makes some sense, see https://github.com/systemd/systemd/issues/3667. Let's
1175 * accept this here, and silently make "--ephemeral --template=" equivalent to "--ephemeral
1176 * --directory=". */
1177
1178 arg_directory = arg_template;
1179 arg_template = NULL;
1180 }
1181
1182 if (arg_template && !(arg_directory || arg_machine)) {
1183 log_error("--template= needs --directory= or --machine=.");
1184 return -EINVAL;
1185 }
1186
1187 if (arg_ephemeral && arg_template) {
1188 log_error("--ephemeral and --template= may not be combined.");
1189 return -EINVAL;
1190 }
1191
1192 if (arg_ephemeral && !IN_SET(arg_link_journal, LINK_NO, LINK_AUTO)) {
1193 log_error("--ephemeral and --link-journal= may not be combined.");
1194 return -EINVAL;
1195 }
1196
1197 if (arg_userns_mode != USER_NAMESPACE_NO && !userns_supported()) {
1198 log_error("--private-users= is not supported, kernel compiled without user namespace support.");
1199 return -EOPNOTSUPP;
1200 }
1201
1202 if (arg_userns_chown && arg_read_only) {
1203 log_error("--read-only and --private-users-chown may not be combined.");
1204 return -EINVAL;
1205 }
1206
1207 if (arg_network_bridge && arg_network_zone) {
1208 log_error("--network-bridge= and --network-zone= may not be combined.");
1209 return -EINVAL;
1210 }
1211
1212 if (argc > optind) {
1213 arg_parameters = strv_copy(argv + optind);
1214 if (!arg_parameters)
1215 return log_oom();
1216
1217 arg_settings_mask |= SETTING_START_MODE;
1218 }
1219
1220 /* Load all settings from .nspawn files */
1221 if (mask_no_settings)
1222 arg_settings_mask = 0;
1223
1224 /* Don't load any settings from .nspawn files */
1225 if (mask_all_settings)
1226 arg_settings_mask = _SETTINGS_MASK_ALL;
1227
1228 arg_caps_retain = (arg_caps_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus;
1229
1230 r = cg_unified_flush();
1231 if (r < 0)
1232 return log_error_errno(r, "Failed to determine whether the unified cgroups hierarchy is used: %m");
1233
1234 e = getenv("SYSTEMD_NSPAWN_CONTAINER_SERVICE");
1235 if (e)
1236 arg_container_service_name = e;
1237
1238 r = getenv_bool("SYSTEMD_NSPAWN_USE_CGNS");
1239 if (r < 0)
1240 arg_use_cgns = cg_ns_supported();
1241 else
1242 arg_use_cgns = r;
1243
1244 r = custom_mount_check_all();
1245 if (r < 0)
1246 return r;
1247
1248 return 1;
1249 }
1250
1251 static int verify_arguments(void) {
1252 if (arg_userns_mode != USER_NAMESPACE_NO && (arg_mount_settings & MOUNT_APPLY_APIVFS_NETNS) && !arg_private_network) {
1253 log_error("Invalid namespacing settings. Mounting sysfs with --private-users requires --private-network.");
1254 return -EINVAL;
1255 }
1256
1257 if (arg_userns_mode != USER_NAMESPACE_NO && !(arg_mount_settings & MOUNT_APPLY_APIVFS_RO)) {
1258 log_error("Cannot combine --private-users with read-write mounts.");
1259 return -EINVAL;
1260 }
1261
1262 if (arg_volatile_mode != VOLATILE_NO && arg_read_only) {
1263 log_error("Cannot combine --read-only with --volatile. Note that --volatile already implies a read-only base hierarchy.");
1264 return -EINVAL;
1265 }
1266
1267 if (arg_expose_ports && !arg_private_network) {
1268 log_error("Cannot use --port= without private networking.");
1269 return -EINVAL;
1270 }
1271
1272 #if ! HAVE_LIBIPTC
1273 if (arg_expose_ports) {
1274 log_error("--port= is not supported, compiled without libiptc support.");
1275 return -EOPNOTSUPP;
1276 }
1277 #endif
1278
1279 if (arg_start_mode == START_BOOT && arg_kill_signal <= 0)
1280 arg_kill_signal = SIGRTMIN+3;
1281
1282 return 0;
1283 }
1284
1285 static int userns_lchown(const char *p, uid_t uid, gid_t gid) {
1286 assert(p);
1287
1288 if (arg_userns_mode == USER_NAMESPACE_NO)
1289 return 0;
1290
1291 if (uid == UID_INVALID && gid == GID_INVALID)
1292 return 0;
1293
1294 if (uid != UID_INVALID) {
1295 uid += arg_uid_shift;
1296
1297 if (uid < arg_uid_shift || uid >= arg_uid_shift + arg_uid_range)
1298 return -EOVERFLOW;
1299 }
1300
1301 if (gid != GID_INVALID) {
1302 gid += (gid_t) arg_uid_shift;
1303
1304 if (gid < (gid_t) arg_uid_shift || gid >= (gid_t) (arg_uid_shift + arg_uid_range))
1305 return -EOVERFLOW;
1306 }
1307
1308 if (lchown(p, uid, gid) < 0)
1309 return -errno;
1310
1311 return 0;
1312 }
1313
1314 static int userns_mkdir(const char *root, const char *path, mode_t mode, uid_t uid, gid_t gid) {
1315 const char *q;
1316 int r;
1317
1318 q = prefix_roota(root, path);
1319 r = mkdir_errno_wrapper(q, mode);
1320 if (r == -EEXIST)
1321 return 0;
1322 if (r < 0)
1323 return r;
1324
1325 return userns_lchown(q, uid, gid);
1326 }
1327
1328 static int setup_timezone(const char *dest) {
1329 _cleanup_free_ char *p = NULL, *q = NULL;
1330 const char *where, *check, *what;
1331 char *z, *y;
1332 int r;
1333
1334 assert(dest);
1335
1336 /* Fix the timezone, if possible */
1337 r = readlink_malloc("/etc/localtime", &p);
1338 if (r < 0) {
1339 log_warning("host's /etc/localtime is not a symlink, not updating container timezone.");
1340 /* to handle warning, delete /etc/localtime and replace it
1341 * with a symbolic link to a time zone data file.
1342 *
1343 * Example:
1344 * ln -s /usr/share/zoneinfo/UTC /etc/localtime
1345 */
1346 return 0;
1347 }
1348
1349 z = path_startswith(p, "../usr/share/zoneinfo/");
1350 if (!z)
1351 z = path_startswith(p, "/usr/share/zoneinfo/");
1352 if (!z) {
1353 log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone.");
1354 return 0;
1355 }
1356
1357 where = prefix_roota(dest, "/etc/localtime");
1358 r = readlink_malloc(where, &q);
1359 if (r >= 0) {
1360 y = path_startswith(q, "../usr/share/zoneinfo/");
1361 if (!y)
1362 y = path_startswith(q, "/usr/share/zoneinfo/");
1363
1364 /* Already pointing to the right place? Then do nothing .. */
1365 if (y && streq(y, z))
1366 return 0;
1367 }
1368
1369 check = strjoina("/usr/share/zoneinfo/", z);
1370 check = prefix_roota(dest, check);
1371 if (laccess(check, F_OK) < 0) {
1372 log_warning("Timezone %s does not exist in container, not updating container timezone.", z);
1373 return 0;
1374 }
1375
1376 if (unlink(where) < 0 && errno != ENOENT) {
1377 log_full_errno(IN_SET(errno, EROFS, EACCES, EPERM) ? LOG_DEBUG : LOG_WARNING, /* Don't complain on read-only images */
1378 errno,
1379 "Failed to remove existing timezone info %s in container, ignoring: %m", where);
1380 return 0;
1381 }
1382
1383 what = strjoina("../usr/share/zoneinfo/", z);
1384 if (symlink(what, where) < 0) {
1385 log_full_errno(IN_SET(errno, EROFS, EACCES, EPERM) ? LOG_DEBUG : LOG_WARNING,
1386 errno,
1387 "Failed to correct timezone of container, ignoring: %m");
1388 return 0;
1389 }
1390
1391 r = userns_lchown(where, 0, 0);
1392 if (r < 0)
1393 return log_warning_errno(r, "Failed to chown /etc/localtime: %m");
1394
1395 return 0;
1396 }
1397
1398 static int resolved_listening(void) {
1399 _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
1400 _cleanup_free_ char *dns_stub_listener_mode = NULL;
1401 int r;
1402
1403 /* Check if resolved is listening */
1404
1405 r = sd_bus_open_system(&bus);
1406 if (r < 0)
1407 return r;
1408
1409 r = bus_name_has_owner(bus, "org.freedesktop.resolve1", NULL);
1410 if (r <= 0)
1411 return r;
1412
1413 r = sd_bus_get_property_string(bus,
1414 "org.freedesktop.resolve1",
1415 "/org/freedesktop/resolve1",
1416 "org.freedesktop.resolve1.Manager",
1417 "DNSStubListener",
1418 NULL,
1419 &dns_stub_listener_mode);
1420 if (r < 0)
1421 return r;
1422
1423 return STR_IN_SET(dns_stub_listener_mode, "udp", "yes");
1424 }
1425
1426 static int setup_resolv_conf(const char *dest) {
1427 _cleanup_free_ char *resolved = NULL, *etc = NULL;
1428 const char *where;
1429 int r, found;
1430
1431 assert(dest);
1432
1433 if (arg_private_network)
1434 return 0;
1435
1436 r = chase_symlinks("/etc", dest, CHASE_PREFIX_ROOT, &etc);
1437 if (r < 0) {
1438 log_warning_errno(r, "Failed to resolve /etc path in container, ignoring: %m");
1439 return 0;
1440 }
1441
1442 where = strjoina(etc, "/resolv.conf");
1443 found = chase_symlinks(where, dest, CHASE_NONEXISTENT, &resolved);
1444 if (found < 0) {
1445 log_warning_errno(found, "Failed to resolve /etc/resolv.conf path in container, ignoring: %m");
1446 return 0;
1447 }
1448
1449 if (access(STATIC_RESOLV_CONF, F_OK) >= 0 &&
1450 resolved_listening() > 0) {
1451
1452 /* resolved is enabled on the host. In this, case bind mount its static resolv.conf file into the
1453 * container, so that the container can use the host's resolver. Given that network namespacing is
1454 * disabled it's only natural of the container also uses the host's resolver. It also has the big
1455 * advantage that the container will be able to follow the host's DNS server configuration changes
1456 * transparently. */
1457
1458 if (found == 0) /* missing? */
1459 (void) touch(resolved);
1460
1461 r = mount_verbose(LOG_DEBUG, STATIC_RESOLV_CONF, resolved, NULL, MS_BIND, NULL);
1462 if (r >= 0)
1463 return mount_verbose(LOG_ERR, NULL, resolved, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NODEV, NULL);
1464 }
1465
1466 /* If that didn't work, let's copy the file */
1467 r = copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW, 0644, 0, COPY_REFLINK);
1468 if (r < 0) {
1469 /* If the file already exists as symlink, let's suppress the warning, under the assumption that
1470 * resolved or something similar runs inside and the symlink points there.
1471 *
1472 * If the disk image is read-only, there's also no point in complaining.
1473 */
1474 log_full_errno(IN_SET(r, -ELOOP, -EROFS, -EACCES, -EPERM) ? LOG_DEBUG : LOG_WARNING, r,
1475 "Failed to copy /etc/resolv.conf to %s, ignoring: %m", where);
1476 return 0;
1477 }
1478
1479 r = userns_lchown(where, 0, 0);
1480 if (r < 0)
1481 log_warning_errno(r, "Failed to chown /etc/resolv.conf, ignoring: %m");
1482
1483 return 0;
1484 }
1485
1486 static int setup_boot_id(const char *dest) {
1487 sd_id128_t rnd = SD_ID128_NULL;
1488 const char *from, *to;
1489 int r;
1490
1491 /* Generate a new randomized boot ID, so that each boot-up of
1492 * the container gets a new one */
1493
1494 from = prefix_roota(dest, "/run/proc-sys-kernel-random-boot-id");
1495 to = prefix_roota(dest, "/proc/sys/kernel/random/boot_id");
1496
1497 r = sd_id128_randomize(&rnd);
1498 if (r < 0)
1499 return log_error_errno(r, "Failed to generate random boot id: %m");
1500
1501 r = id128_write(from, ID128_UUID, rnd, false);
1502 if (r < 0)
1503 return log_error_errno(r, "Failed to write boot id: %m");
1504
1505 r = mount_verbose(LOG_ERR, from, to, NULL, MS_BIND, NULL);
1506 if (r >= 0)
1507 r = mount_verbose(LOG_ERR, NULL, to, NULL,
1508 MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NODEV, NULL);
1509
1510 (void) unlink(from);
1511 return r;
1512 }
1513
1514 static int copy_devnodes(const char *dest) {
1515
1516 static const char devnodes[] =
1517 "null\0"
1518 "zero\0"
1519 "full\0"
1520 "random\0"
1521 "urandom\0"
1522 "tty\0"
1523 "net/tun\0";
1524
1525 const char *d;
1526 int r = 0;
1527 _cleanup_umask_ mode_t u;
1528
1529 assert(dest);
1530
1531 u = umask(0000);
1532
1533 /* Create /dev/net, so that we can create /dev/net/tun in it */
1534 if (userns_mkdir(dest, "/dev/net", 0755, 0, 0) < 0)
1535 return log_error_errno(r, "Failed to create /dev/net directory: %m");
1536
1537 NULSTR_FOREACH(d, devnodes) {
1538 _cleanup_free_ char *from = NULL, *to = NULL;
1539 struct stat st;
1540
1541 from = strappend("/dev/", d);
1542 to = prefix_root(dest, from);
1543
1544 if (stat(from, &st) < 0) {
1545
1546 if (errno != ENOENT)
1547 return log_error_errno(errno, "Failed to stat %s: %m", from);
1548
1549 } else if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
1550
1551 log_error("%s is not a char or block device, cannot copy.", from);
1552 return -EIO;
1553
1554 } else {
1555 if (mknod(to, st.st_mode, st.st_rdev) < 0) {
1556 /* Explicitly warn the user when /dev is already populated. */
1557 if (errno == EEXIST)
1558 log_notice("%s/dev is pre-mounted and pre-populated. If a pre-mounted /dev is provided it needs to be an unpopulated file system.", dest);
1559 if (errno != EPERM)
1560 return log_error_errno(errno, "mknod(%s) failed: %m", to);
1561
1562 /* Some systems abusively restrict mknod but
1563 * allow bind mounts. */
1564 r = touch(to);
1565 if (r < 0)
1566 return log_error_errno(r, "touch (%s) failed: %m", to);
1567 r = mount_verbose(LOG_DEBUG, from, to, NULL, MS_BIND, NULL);
1568 if (r < 0)
1569 return log_error_errno(r, "Both mknod and bind mount (%s) failed: %m", to);
1570 }
1571
1572 r = userns_lchown(to, 0, 0);
1573 if (r < 0)
1574 return log_error_errno(r, "chown() of device node %s failed: %m", to);
1575 }
1576 }
1577
1578 return r;
1579 }
1580
1581 static int setup_pts(const char *dest) {
1582 _cleanup_free_ char *options = NULL;
1583 const char *p;
1584 int r;
1585
1586 #if HAVE_SELINUX
1587 if (arg_selinux_apifs_context)
1588 (void) asprintf(&options,
1589 "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT ",context=\"%s\"",
1590 arg_uid_shift + TTY_GID,
1591 arg_selinux_apifs_context);
1592 else
1593 #endif
1594 (void) asprintf(&options,
1595 "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT,
1596 arg_uid_shift + TTY_GID);
1597
1598 if (!options)
1599 return log_oom();
1600
1601 /* Mount /dev/pts itself */
1602 p = prefix_roota(dest, "/dev/pts");
1603 r = mkdir_errno_wrapper(p, 0755);
1604 if (r < 0)
1605 return log_error_errno(r, "Failed to create /dev/pts: %m");
1606
1607 r = mount_verbose(LOG_ERR, "devpts", p, "devpts", MS_NOSUID|MS_NOEXEC, options);
1608 if (r < 0)
1609 return r;
1610 r = userns_lchown(p, 0, 0);
1611 if (r < 0)
1612 return log_error_errno(r, "Failed to chown /dev/pts: %m");
1613
1614 /* Create /dev/ptmx symlink */
1615 p = prefix_roota(dest, "/dev/ptmx");
1616 if (symlink("pts/ptmx", p) < 0)
1617 return log_error_errno(errno, "Failed to create /dev/ptmx symlink: %m");
1618 r = userns_lchown(p, 0, 0);
1619 if (r < 0)
1620 return log_error_errno(r, "Failed to chown /dev/ptmx: %m");
1621
1622 /* And fix /dev/pts/ptmx ownership */
1623 p = prefix_roota(dest, "/dev/pts/ptmx");
1624 r = userns_lchown(p, 0, 0);
1625 if (r < 0)
1626 return log_error_errno(r, "Failed to chown /dev/pts/ptmx: %m");
1627
1628 return 0;
1629 }
1630
1631 static int setup_dev_console(const char *dest, const char *console) {
1632 _cleanup_umask_ mode_t u;
1633 const char *to;
1634 int r;
1635
1636 assert(dest);
1637 assert(console);
1638
1639 u = umask(0000);
1640
1641 r = chmod_and_chown(console, 0600, arg_uid_shift, arg_uid_shift);
1642 if (r < 0)
1643 return log_error_errno(r, "Failed to correct access mode for TTY: %m");
1644
1645 /* We need to bind mount the right tty to /dev/console since
1646 * ptys can only exist on pts file systems. To have something
1647 * to bind mount things on we create a empty regular file. */
1648
1649 to = prefix_roota(dest, "/dev/console");
1650 r = touch(to);
1651 if (r < 0)
1652 return log_error_errno(r, "touch() for /dev/console failed: %m");
1653
1654 return mount_verbose(LOG_ERR, console, to, NULL, MS_BIND, NULL);
1655 }
1656
1657 static int setup_keyring(void) {
1658 key_serial_t keyring;
1659
1660 /* Allocate a new session keyring for the container. This makes sure the keyring of the session systemd-nspawn
1661 * was invoked from doesn't leak into the container. Note that by default we block keyctl() and request_key()
1662 * anyway via seccomp so doing this operation isn't strictly necessary, but in case people explicitly whitelist
1663 * these system calls let's make sure we don't leak anything into the container. */
1664
1665 keyring = keyctl(KEYCTL_JOIN_SESSION_KEYRING, 0, 0, 0, 0);
1666 if (keyring == -1) {
1667 if (errno == ENOSYS)
1668 log_debug_errno(errno, "Kernel keyring not supported, ignoring.");
1669 else if (IN_SET(errno, EACCES, EPERM))
1670 log_debug_errno(errno, "Kernel keyring access prohibited, ignoring.");
1671 else
1672 return log_error_errno(errno, "Setting up kernel keyring failed: %m");
1673 }
1674
1675 return 0;
1676 }
1677
1678 static int setup_kmsg(const char *dest, int kmsg_socket) {
1679 const char *from, *to;
1680 _cleanup_umask_ mode_t u;
1681 int fd, r;
1682
1683 assert(kmsg_socket >= 0);
1684
1685 u = umask(0000);
1686
1687 /* We create the kmsg FIFO as /run/kmsg, but immediately
1688 * delete it after bind mounting it to /proc/kmsg. While FIFOs
1689 * on the reading side behave very similar to /proc/kmsg,
1690 * their writing side behaves differently from /dev/kmsg in
1691 * that writing blocks when nothing is reading. In order to
1692 * avoid any problems with containers deadlocking due to this
1693 * we simply make /dev/kmsg unavailable to the container. */
1694 from = prefix_roota(dest, "/run/kmsg");
1695 to = prefix_roota(dest, "/proc/kmsg");
1696
1697 if (mkfifo(from, 0600) < 0)
1698 return log_error_errno(errno, "mkfifo() for /run/kmsg failed: %m");
1699 r = mount_verbose(LOG_ERR, from, to, NULL, MS_BIND, NULL);
1700 if (r < 0)
1701 return r;
1702
1703 fd = open(from, O_RDWR|O_NDELAY|O_CLOEXEC);
1704 if (fd < 0)
1705 return log_error_errno(errno, "Failed to open fifo: %m");
1706
1707 /* Store away the fd in the socket, so that it stays open as
1708 * long as we run the child */
1709 r = send_one_fd(kmsg_socket, fd, 0);
1710 safe_close(fd);
1711
1712 if (r < 0)
1713 return log_error_errno(r, "Failed to send FIFO fd: %m");
1714
1715 /* And now make the FIFO unavailable as /run/kmsg... */
1716 (void) unlink(from);
1717
1718 return 0;
1719 }
1720
1721 static int on_address_change(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {
1722 union in_addr_union *exposed = userdata;
1723
1724 assert(rtnl);
1725 assert(m);
1726 assert(exposed);
1727
1728 expose_port_execute(rtnl, arg_expose_ports, exposed);
1729 return 0;
1730 }
1731
1732 static int setup_hostname(void) {
1733
1734 if ((arg_clone_ns_flags & CLONE_NEWUTS) == 0)
1735 return 0;
1736
1737 if (sethostname_idempotent(arg_machine) < 0)
1738 return -errno;
1739
1740 return 0;
1741 }
1742
1743 static int setup_journal(const char *directory) {
1744 sd_id128_t this_id;
1745 _cleanup_free_ char *d = NULL;
1746 const char *p, *q;
1747 bool try;
1748 char id[33];
1749 int r;
1750
1751 /* Don't link journals in ephemeral mode */
1752 if (arg_ephemeral)
1753 return 0;
1754
1755 if (arg_link_journal == LINK_NO)
1756 return 0;
1757
1758 try = arg_link_journal_try || arg_link_journal == LINK_AUTO;
1759
1760 r = sd_id128_get_machine(&this_id);
1761 if (r < 0)
1762 return log_error_errno(r, "Failed to retrieve machine ID: %m");
1763
1764 if (sd_id128_equal(arg_uuid, this_id)) {
1765 log_full(try ? LOG_WARNING : LOG_ERR,
1766 "Host and machine ids are equal (%s): refusing to link journals", sd_id128_to_string(arg_uuid, id));
1767 if (try)
1768 return 0;
1769 return -EEXIST;
1770 }
1771
1772 r = userns_mkdir(directory, "/var", 0755, 0, 0);
1773 if (r < 0)
1774 return log_error_errno(r, "Failed to create /var: %m");
1775
1776 r = userns_mkdir(directory, "/var/log", 0755, 0, 0);
1777 if (r < 0)
1778 return log_error_errno(r, "Failed to create /var/log: %m");
1779
1780 r = userns_mkdir(directory, "/var/log/journal", 0755, 0, 0);
1781 if (r < 0)
1782 return log_error_errno(r, "Failed to create /var/log/journal: %m");
1783
1784 (void) sd_id128_to_string(arg_uuid, id);
1785
1786 p = strjoina("/var/log/journal/", id);
1787 q = prefix_roota(directory, p);
1788
1789 if (path_is_mount_point(p, NULL, 0) > 0) {
1790 if (try)
1791 return 0;
1792
1793 log_error("%s: already a mount point, refusing to use for journal", p);
1794 return -EEXIST;
1795 }
1796
1797 if (path_is_mount_point(q, NULL, 0) > 0) {
1798 if (try)
1799 return 0;
1800
1801 log_error("%s: already a mount point, refusing to use for journal", q);
1802 return -EEXIST;
1803 }
1804
1805 r = readlink_and_make_absolute(p, &d);
1806 if (r >= 0) {
1807 if (IN_SET(arg_link_journal, LINK_GUEST, LINK_AUTO) &&
1808 path_equal(d, q)) {
1809
1810 r = userns_mkdir(directory, p, 0755, 0, 0);
1811 if (r < 0)
1812 log_warning_errno(r, "Failed to create directory %s: %m", q);
1813 return 0;
1814 }
1815
1816 if (unlink(p) < 0)
1817 return log_error_errno(errno, "Failed to remove symlink %s: %m", p);
1818 } else if (r == -EINVAL) {
1819
1820 if (arg_link_journal == LINK_GUEST &&
1821 rmdir(p) < 0) {
1822
1823 if (errno == ENOTDIR) {
1824 log_error("%s already exists and is neither a symlink nor a directory", p);
1825 return r;
1826 } else
1827 return log_error_errno(errno, "Failed to remove %s: %m", p);
1828 }
1829 } else if (r != -ENOENT)
1830 return log_error_errno(r, "readlink(%s) failed: %m", p);
1831
1832 if (arg_link_journal == LINK_GUEST) {
1833
1834 if (symlink(q, p) < 0) {
1835 if (try) {
1836 log_debug_errno(errno, "Failed to symlink %s to %s, skipping journal setup: %m", q, p);
1837 return 0;
1838 } else
1839 return log_error_errno(errno, "Failed to symlink %s to %s: %m", q, p);
1840 }
1841
1842 r = userns_mkdir(directory, p, 0755, 0, 0);
1843 if (r < 0)
1844 log_warning_errno(r, "Failed to create directory %s: %m", q);
1845 return 0;
1846 }
1847
1848 if (arg_link_journal == LINK_HOST) {
1849 /* don't create parents here — if the host doesn't have
1850 * permanent journal set up, don't force it here */
1851
1852 r = mkdir_errno_wrapper(p, 0755);
1853 if (r < 0 && r != -EEXIST) {
1854 if (try) {
1855 log_debug_errno(r, "Failed to create %s, skipping journal setup: %m", p);
1856 return 0;
1857 } else
1858 return log_error_errno(r, "Failed to create %s: %m", p);
1859 }
1860
1861 } else if (access(p, F_OK) < 0)
1862 return 0;
1863
1864 if (dir_is_empty(q) == 0)
1865 log_warning("%s is not empty, proceeding anyway.", q);
1866
1867 r = userns_mkdir(directory, p, 0755, 0, 0);
1868 if (r < 0)
1869 return log_error_errno(r, "Failed to create %s: %m", q);
1870
1871 r = mount_verbose(LOG_DEBUG, p, q, NULL, MS_BIND, NULL);
1872 if (r < 0)
1873 return log_error_errno(errno, "Failed to bind mount journal from host into guest: %m");
1874
1875 return 0;
1876 }
1877
1878 static int drop_capabilities(void) {
1879 return capability_bounding_set_drop(arg_caps_retain, false);
1880 }
1881
1882 static int reset_audit_loginuid(void) {
1883 _cleanup_free_ char *p = NULL;
1884 int r;
1885
1886 if ((arg_clone_ns_flags & CLONE_NEWPID) == 0)
1887 return 0;
1888
1889 r = read_one_line_file("/proc/self/loginuid", &p);
1890 if (r == -ENOENT)
1891 return 0;
1892 if (r < 0)
1893 return log_error_errno(r, "Failed to read /proc/self/loginuid: %m");
1894
1895 /* Already reset? */
1896 if (streq(p, "4294967295"))
1897 return 0;
1898
1899 r = write_string_file("/proc/self/loginuid", "4294967295", 0);
1900 if (r < 0) {
1901 log_error_errno(r,
1902 "Failed to reset audit login UID. This probably means that your kernel is too\n"
1903 "old and you have audit enabled. Note that the auditing subsystem is known to\n"
1904 "be incompatible with containers on old kernels. Please make sure to upgrade\n"
1905 "your kernel or to off auditing with 'audit=0' on the kernel command line before\n"
1906 "using systemd-nspawn. Sleeping for 5s... (%m)");
1907
1908 sleep(5);
1909 }
1910
1911 return 0;
1912 }
1913
1914
1915 static int setup_propagate(const char *root) {
1916 const char *p, *q;
1917 int r;
1918
1919 (void) mkdir_p("/run/systemd/nspawn/", 0755);
1920 (void) mkdir_p("/run/systemd/nspawn/propagate", 0600);
1921 p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
1922 (void) mkdir_p(p, 0600);
1923
1924 r = userns_mkdir(root, "/run/systemd", 0755, 0, 0);
1925 if (r < 0)
1926 return log_error_errno(r, "Failed to create /run/systemd: %m");
1927
1928 r = userns_mkdir(root, "/run/systemd/nspawn", 0755, 0, 0);
1929 if (r < 0)
1930 return log_error_errno(r, "Failed to create /run/systemd/nspawn: %m");
1931
1932 r = userns_mkdir(root, "/run/systemd/nspawn/incoming", 0600, 0, 0);
1933 if (r < 0)
1934 return log_error_errno(r, "Failed to create /run/systemd/nspawn/incoming: %m");
1935
1936 q = prefix_roota(root, "/run/systemd/nspawn/incoming");
1937 r = mount_verbose(LOG_ERR, p, q, NULL, MS_BIND, NULL);
1938 if (r < 0)
1939 return r;
1940
1941 r = mount_verbose(LOG_ERR, NULL, q, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY, NULL);
1942 if (r < 0)
1943 return r;
1944
1945 /* machined will MS_MOVE into that directory, and that's only
1946 * supported for non-shared mounts. */
1947 return mount_verbose(LOG_ERR, NULL, q, NULL, MS_SLAVE, NULL);
1948 }
1949
1950 static int setup_machine_id(const char *directory) {
1951 const char *etc_machine_id;
1952 sd_id128_t id;
1953 int r;
1954
1955 /* If the UUID in the container is already set, then that's what counts, and we use. If it isn't set, and the
1956 * caller passed --uuid=, then we'll pass it in the $container_uuid env var to PID 1 of the container. The
1957 * assumption is that PID 1 will then write it to /etc/machine-id to make it persistent. If --uuid= is not
1958 * passed we generate a random UUID, and pass it via $container_uuid. In effect this means that /etc/machine-id
1959 * in the container and our idea of the container UUID will always be in sync (at least if PID 1 in the
1960 * container behaves nicely). */
1961
1962 etc_machine_id = prefix_roota(directory, "/etc/machine-id");
1963
1964 r = id128_read(etc_machine_id, ID128_PLAIN, &id);
1965 if (r < 0) {
1966 if (!IN_SET(r, -ENOENT, -ENOMEDIUM)) /* If the file is missing or empty, we don't mind */
1967 return log_error_errno(r, "Failed to read machine ID from container image: %m");
1968
1969 if (sd_id128_is_null(arg_uuid)) {
1970 r = sd_id128_randomize(&arg_uuid);
1971 if (r < 0)
1972 return log_error_errno(r, "Failed to acquire randomized machine UUID: %m");
1973 }
1974 } else {
1975 if (sd_id128_is_null(id)) {
1976 log_error("Machine ID in container image is zero, refusing.");
1977 return -EINVAL;
1978 }
1979
1980 arg_uuid = id;
1981 }
1982
1983 return 0;
1984 }
1985
1986 static int recursive_chown(const char *directory, uid_t shift, uid_t range) {
1987 int r;
1988
1989 assert(directory);
1990
1991 if (arg_userns_mode == USER_NAMESPACE_NO || !arg_userns_chown)
1992 return 0;
1993
1994 r = path_patch_uid(directory, arg_uid_shift, arg_uid_range);
1995 if (r == -EOPNOTSUPP)
1996 return log_error_errno(r, "Automatic UID/GID adjusting is only supported for UID/GID ranges starting at multiples of 2^16 with a range of 2^16.");
1997 if (r == -EBADE)
1998 return log_error_errno(r, "Upper 16 bits of root directory UID and GID do not match.");
1999 if (r < 0)
2000 return log_error_errno(r, "Failed to adjust UID/GID shift of OS tree: %m");
2001 if (r == 0)
2002 log_debug("Root directory of image is already owned by the right UID/GID range, skipping recursive chown operation.");
2003 else
2004 log_debug("Patched directory tree to match UID/GID range.");
2005
2006 return r;
2007 }
2008
2009 /*
2010 * Return values:
2011 * < 0 : wait_for_terminate() failed to get the state of the
2012 * container, the container was terminated by a signal, or
2013 * failed for an unknown reason. No change is made to the
2014 * container argument.
2015 * > 0 : The program executed in the container terminated with an
2016 * error. The exit code of the program executed in the
2017 * container is returned. The container argument has been set
2018 * to CONTAINER_TERMINATED.
2019 * 0 : The container is being rebooted, has been shut down or exited
2020 * successfully. The container argument has been set to either
2021 * CONTAINER_TERMINATED or CONTAINER_REBOOTED.
2022 *
2023 * That is, success is indicated by a return value of zero, and an
2024 * error is indicated by a non-zero value.
2025 */
2026 static int wait_for_container(pid_t pid, ContainerStatus *container) {
2027 siginfo_t status;
2028 int r;
2029
2030 r = wait_for_terminate(pid, &status);
2031 if (r < 0)
2032 return log_warning_errno(r, "Failed to wait for container: %m");
2033
2034 switch (status.si_code) {
2035
2036 case CLD_EXITED:
2037 if (status.si_status == 0)
2038 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s exited successfully.", arg_machine);
2039 else
2040 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s failed with error code %i.", arg_machine, status.si_status);
2041
2042 *container = CONTAINER_TERMINATED;
2043 return status.si_status;
2044
2045 case CLD_KILLED:
2046 if (status.si_status == SIGINT) {
2047 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s has been shut down.", arg_machine);
2048 *container = CONTAINER_TERMINATED;
2049 return 0;
2050
2051 } else if (status.si_status == SIGHUP) {
2052 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s is being rebooted.", arg_machine);
2053 *container = CONTAINER_REBOOTED;
2054 return 0;
2055 }
2056
2057 _fallthrough_;
2058 case CLD_DUMPED:
2059 log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status));
2060 return -EIO;
2061
2062 default:
2063 log_error("Container %s failed due to unknown reason.", arg_machine);
2064 return -EIO;
2065 }
2066 }
2067
2068 static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
2069 pid_t pid;
2070
2071 pid = PTR_TO_PID(userdata);
2072 if (pid > 0) {
2073 if (kill(pid, arg_kill_signal) >= 0) {
2074 log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
2075 sd_event_source_set_userdata(s, NULL);
2076 return 0;
2077 }
2078 }
2079
2080 sd_event_exit(sd_event_source_get_event(s), 0);
2081 return 0;
2082 }
2083
2084 static int on_sigchld(sd_event_source *s, const struct signalfd_siginfo *ssi, void *userdata) {
2085 pid_t pid;
2086
2087 assert(s);
2088 assert(ssi);
2089
2090 pid = PTR_TO_PID(userdata);
2091
2092 for (;;) {
2093 siginfo_t si = {};
2094
2095 if (waitid(P_ALL, 0, &si, WNOHANG|WNOWAIT|WEXITED) < 0)
2096 return log_error_errno(errno, "Failed to waitid(): %m");
2097 if (si.si_pid == 0) /* No pending children. */
2098 break;
2099 if (si.si_pid == pid) {
2100 /* The main process we care for has exited. Return from
2101 * signal handler but leave the zombie. */
2102 sd_event_exit(sd_event_source_get_event(s), 0);
2103 break;
2104 }
2105
2106 /* Reap all other children. */
2107 (void) waitid(P_PID, si.si_pid, &si, WNOHANG|WEXITED);
2108 }
2109
2110 return 0;
2111 }
2112
2113 static int on_request_stop(sd_bus_message *m, void *userdata, sd_bus_error *error) {
2114 pid_t pid;
2115
2116 assert(m);
2117
2118 pid = PTR_TO_PID(userdata);
2119
2120 if (arg_kill_signal > 0) {
2121 log_info("Container termination requested. Attempting to halt container.");
2122 (void) kill(pid, arg_kill_signal);
2123 } else {
2124 log_info("Container termination requested. Exiting.");
2125 sd_event_exit(sd_bus_get_event(sd_bus_message_get_bus(m)), 0);
2126 }
2127
2128 return 0;
2129 }
2130
2131 static int determine_names(void) {
2132 int r;
2133
2134 if (arg_template && !arg_directory && arg_machine) {
2135
2136 /* If --template= was specified then we should not
2137 * search for a machine, but instead create a new one
2138 * in /var/lib/machine. */
2139
2140 arg_directory = strjoin("/var/lib/machines/", arg_machine);
2141 if (!arg_directory)
2142 return log_oom();
2143 }
2144
2145 if (!arg_image && !arg_directory) {
2146 if (arg_machine) {
2147 _cleanup_(image_unrefp) Image *i = NULL;
2148
2149 r = image_find(arg_machine, &i);
2150 if (r < 0)
2151 return log_error_errno(r, "Failed to find image for machine '%s': %m", arg_machine);
2152 if (r == 0) {
2153 log_error("No image for machine '%s'.", arg_machine);
2154 return -ENOENT;
2155 }
2156
2157 if (IN_SET(i->type, IMAGE_RAW, IMAGE_BLOCK))
2158 r = free_and_strdup(&arg_image, i->path);
2159 else
2160 r = free_and_strdup(&arg_directory, i->path);
2161 if (r < 0)
2162 return log_oom();
2163
2164 if (!arg_ephemeral)
2165 arg_read_only = arg_read_only || i->read_only;
2166 } else {
2167 r = safe_getcwd(&arg_directory);
2168 if (r < 0)
2169 return log_error_errno(r, "Failed to determine current directory: %m");
2170 }
2171
2172 if (!arg_directory && !arg_image) {
2173 log_error("Failed to determine path, please use -D or -i.");
2174 return -EINVAL;
2175 }
2176 }
2177
2178 if (!arg_machine) {
2179
2180 if (arg_directory && path_equal(arg_directory, "/"))
2181 arg_machine = gethostname_malloc();
2182 else {
2183 if (arg_image) {
2184 char *e;
2185
2186 arg_machine = strdup(basename(arg_image));
2187
2188 /* Truncate suffix if there is one */
2189 e = endswith(arg_machine, ".raw");
2190 if (e)
2191 *e = 0;
2192 } else
2193 arg_machine = strdup(basename(arg_directory));
2194 }
2195 if (!arg_machine)
2196 return log_oom();
2197
2198 hostname_cleanup(arg_machine);
2199 if (!machine_name_is_valid(arg_machine)) {
2200 log_error("Failed to determine machine name automatically, please use -M.");
2201 return -EINVAL;
2202 }
2203
2204 if (arg_ephemeral) {
2205 char *b;
2206
2207 /* Add a random suffix when this is an
2208 * ephemeral machine, so that we can run many
2209 * instances at once without manually having
2210 * to specify -M each time. */
2211
2212 if (asprintf(&b, "%s-%016" PRIx64, arg_machine, random_u64()) < 0)
2213 return log_oom();
2214
2215 free(arg_machine);
2216 arg_machine = b;
2217 }
2218 }
2219
2220 return 0;
2221 }
2222
2223 static int chase_symlinks_and_update(char **p, unsigned flags) {
2224 char *chased;
2225 int r;
2226
2227 assert(p);
2228
2229 if (!*p)
2230 return 0;
2231
2232 r = chase_symlinks(*p, NULL, flags, &chased);
2233 if (r < 0)
2234 return log_error_errno(r, "Failed to resolve path %s: %m", *p);
2235
2236 free_and_replace(*p, chased);
2237 return r; /* r might be an fd here in case we ever use CHASE_OPEN in flags */
2238 }
2239
2240 static int determine_uid_shift(const char *directory) {
2241 int r;
2242
2243 if (arg_userns_mode == USER_NAMESPACE_NO) {
2244 arg_uid_shift = 0;
2245 return 0;
2246 }
2247
2248 if (arg_uid_shift == UID_INVALID) {
2249 struct stat st;
2250
2251 r = stat(directory, &st);
2252 if (r < 0)
2253 return log_error_errno(errno, "Failed to determine UID base of %s: %m", directory);
2254
2255 arg_uid_shift = st.st_uid & UINT32_C(0xffff0000);
2256
2257 if (arg_uid_shift != (st.st_gid & UINT32_C(0xffff0000))) {
2258 log_error("UID and GID base of %s don't match.", directory);
2259 return -EINVAL;
2260 }
2261
2262 arg_uid_range = UINT32_C(0x10000);
2263 }
2264
2265 if (arg_uid_shift > (uid_t) -1 - arg_uid_range) {
2266 log_error("UID base too high for UID range.");
2267 return -EINVAL;
2268 }
2269
2270 return 0;
2271 }
2272
2273 static int inner_child(
2274 Barrier *barrier,
2275 const char *directory,
2276 bool secondary,
2277 int kmsg_socket,
2278 int rtnl_socket,
2279 FDSet *fds) {
2280
2281 _cleanup_free_ char *home = NULL;
2282 char as_uuid[37];
2283 unsigned n_env = 1;
2284 const char *envp[] = {
2285 "PATH=" DEFAULT_PATH_SPLIT_USR,
2286 NULL, /* container */
2287 NULL, /* TERM */
2288 NULL, /* HOME */
2289 NULL, /* USER */
2290 NULL, /* LOGNAME */
2291 NULL, /* container_uuid */
2292 NULL, /* LISTEN_FDS */
2293 NULL, /* LISTEN_PID */
2294 NULL, /* NOTIFY_SOCKET */
2295 NULL
2296 };
2297 const char *exec_target;
2298
2299 _cleanup_strv_free_ char **env_use = NULL;
2300 int r;
2301
2302 assert(barrier);
2303 assert(directory);
2304 assert(kmsg_socket >= 0);
2305
2306 if (arg_userns_mode != USER_NAMESPACE_NO) {
2307 /* Tell the parent, that it now can write the UID map. */
2308 (void) barrier_place(barrier); /* #1 */
2309
2310 /* Wait until the parent wrote the UID map */
2311 if (!barrier_place_and_sync(barrier)) { /* #2 */
2312 log_error("Parent died too early");
2313 return -ESRCH;
2314 }
2315 }
2316
2317 r = reset_uid_gid();
2318 if (r < 0)
2319 return log_error_errno(r, "Couldn't become new root: %m");
2320
2321 r = mount_all(NULL,
2322 arg_mount_settings | MOUNT_IN_USERNS,
2323 arg_uid_shift,
2324 arg_uid_range,
2325 arg_selinux_apifs_context);
2326
2327 if (r < 0)
2328 return r;
2329
2330 r = mount_sysfs(NULL, arg_mount_settings);
2331 if (r < 0)
2332 return r;
2333
2334 /* Wait until we are cgroup-ified, so that we
2335 * can mount the right cgroup path writable */
2336 if (!barrier_place_and_sync(barrier)) { /* #3 */
2337 log_error("Parent died too early");
2338 return -ESRCH;
2339 }
2340
2341 if (arg_use_cgns && cg_ns_supported()) {
2342 r = unshare(CLONE_NEWCGROUP);
2343 if (r < 0)
2344 return log_error_errno(errno, "Failed to unshare cgroup namespace");
2345 r = mount_cgroups(
2346 "",
2347 arg_unified_cgroup_hierarchy,
2348 arg_userns_mode != USER_NAMESPACE_NO,
2349 arg_uid_shift,
2350 arg_uid_range,
2351 arg_selinux_apifs_context,
2352 true);
2353 if (r < 0)
2354 return r;
2355 } else {
2356 r = mount_systemd_cgroup_writable("", arg_unified_cgroup_hierarchy);
2357 if (r < 0)
2358 return r;
2359 }
2360
2361 r = setup_boot_id(NULL);
2362 if (r < 0)
2363 return r;
2364
2365 r = setup_kmsg(NULL, kmsg_socket);
2366 if (r < 0)
2367 return r;
2368 kmsg_socket = safe_close(kmsg_socket);
2369
2370 umask(0022);
2371
2372 if (setsid() < 0)
2373 return log_error_errno(errno, "setsid() failed: %m");
2374
2375 if (arg_private_network)
2376 loopback_setup();
2377
2378 if (arg_expose_ports) {
2379 r = expose_port_send_rtnl(rtnl_socket);
2380 if (r < 0)
2381 return r;
2382 rtnl_socket = safe_close(rtnl_socket);
2383 }
2384
2385 r = drop_capabilities();
2386 if (r < 0)
2387 return log_error_errno(r, "drop_capabilities() failed: %m");
2388
2389 setup_hostname();
2390
2391 if (arg_personality != PERSONALITY_INVALID) {
2392 r = safe_personality(arg_personality);
2393 if (r < 0)
2394 return log_error_errno(r, "personality() failed: %m");
2395 } else if (secondary) {
2396 r = safe_personality(PER_LINUX32);
2397 if (r < 0)
2398 return log_error_errno(r, "personality() failed: %m");
2399 }
2400
2401 #if HAVE_SELINUX
2402 if (arg_selinux_context)
2403 if (setexeccon(arg_selinux_context) < 0)
2404 return log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context);
2405 #endif
2406
2407 r = change_uid_gid(arg_user, &home);
2408 if (r < 0)
2409 return r;
2410
2411 /* LXC sets container=lxc, so follow the scheme here */
2412 envp[n_env++] = strjoina("container=", arg_container_service_name);
2413
2414 envp[n_env] = strv_find_prefix(environ, "TERM=");
2415 if (envp[n_env])
2416 n_env++;
2417
2418 if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) ||
2419 (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) ||
2420 (asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0))
2421 return log_oom();
2422
2423 assert(!sd_id128_is_null(arg_uuid));
2424
2425 if (asprintf((char**)(envp + n_env++), "container_uuid=%s", id128_to_uuid_string(arg_uuid, as_uuid)) < 0)
2426 return log_oom();
2427
2428 if (fdset_size(fds) > 0) {
2429 r = fdset_cloexec(fds, false);
2430 if (r < 0)
2431 return log_error_errno(r, "Failed to unset O_CLOEXEC for file descriptors.");
2432
2433 if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", fdset_size(fds)) < 0) ||
2434 (asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0))
2435 return log_oom();
2436 }
2437 if (asprintf((char **)(envp + n_env++), "NOTIFY_SOCKET=%s", NSPAWN_NOTIFY_SOCKET_PATH) < 0)
2438 return log_oom();
2439
2440 env_use = strv_env_merge(2, envp, arg_setenv);
2441 if (!env_use)
2442 return log_oom();
2443
2444 /* Let the parent know that we are ready and
2445 * wait until the parent is ready with the
2446 * setup, too... */
2447 if (!barrier_place_and_sync(barrier)) { /* #4 */
2448 log_error("Parent died too early");
2449 return -ESRCH;
2450 }
2451
2452 if (arg_chdir)
2453 if (chdir(arg_chdir) < 0)
2454 return log_error_errno(errno, "Failed to change to specified working directory %s: %m", arg_chdir);
2455
2456 if (arg_start_mode == START_PID2) {
2457 r = stub_pid1(arg_uuid);
2458 if (r < 0)
2459 return r;
2460 }
2461
2462 /* Now, explicitly close the log, so that we
2463 * then can close all remaining fds. Closing
2464 * the log explicitly first has the benefit
2465 * that the logging subsystem knows about it,
2466 * and is thus ready to be reopened should we
2467 * need it again. Note that the other fds
2468 * closed here are at least the locking and
2469 * barrier fds. */
2470 log_close();
2471 (void) fdset_close_others(fds);
2472
2473 if (arg_start_mode == START_BOOT) {
2474 char **a;
2475 size_t m;
2476
2477 /* Automatically search for the init system */
2478
2479 m = strv_length(arg_parameters);
2480 a = newa(char*, m + 2);
2481 memcpy_safe(a + 1, arg_parameters, m * sizeof(char*));
2482 a[1 + m] = NULL;
2483
2484 a[0] = (char*) "/usr/lib/systemd/systemd";
2485 execve(a[0], a, env_use);
2486
2487 a[0] = (char*) "/lib/systemd/systemd";
2488 execve(a[0], a, env_use);
2489
2490 a[0] = (char*) "/sbin/init";
2491 execve(a[0], a, env_use);
2492
2493 exec_target = "/usr/lib/systemd/systemd, /lib/systemd/systemd, /sbin/init";
2494 } else if (!strv_isempty(arg_parameters)) {
2495 exec_target = arg_parameters[0];
2496 execvpe(arg_parameters[0], arg_parameters, env_use);
2497 } else {
2498 if (!arg_chdir)
2499 /* If we cannot change the directory, we'll end up in /, that is expected. */
2500 (void) chdir(home ?: "/root");
2501
2502 execle("/bin/bash", "-bash", NULL, env_use);
2503 execle("/bin/sh", "-sh", NULL, env_use);
2504
2505 exec_target = "/bin/bash, /bin/sh";
2506 }
2507
2508 r = -errno;
2509 (void) log_open();
2510 return log_error_errno(r, "execv(%s) failed: %m", exec_target);
2511 }
2512
2513 static int setup_sd_notify_child(void) {
2514 static const int one = 1;
2515 int fd = -1;
2516 union sockaddr_union sa = {
2517 .sa.sa_family = AF_UNIX,
2518 };
2519 int r;
2520
2521 fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
2522 if (fd < 0)
2523 return log_error_errno(errno, "Failed to allocate notification socket: %m");
2524
2525 (void) mkdir_parents(NSPAWN_NOTIFY_SOCKET_PATH, 0755);
2526 (void) unlink(NSPAWN_NOTIFY_SOCKET_PATH);
2527
2528 strncpy(sa.un.sun_path, NSPAWN_NOTIFY_SOCKET_PATH, sizeof(sa.un.sun_path)-1);
2529 r = bind(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un));
2530 if (r < 0) {
2531 safe_close(fd);
2532 return log_error_errno(errno, "bind(%s) failed: %m", sa.un.sun_path);
2533 }
2534
2535 r = userns_lchown(NSPAWN_NOTIFY_SOCKET_PATH, 0, 0);
2536 if (r < 0) {
2537 safe_close(fd);
2538 return log_error_errno(r, "Failed to chown " NSPAWN_NOTIFY_SOCKET_PATH ": %m");
2539 }
2540
2541 r = setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one));
2542 if (r < 0) {
2543 safe_close(fd);
2544 return log_error_errno(errno, "SO_PASSCRED failed: %m");
2545 }
2546
2547 return fd;
2548 }
2549
2550 static int outer_child(
2551 Barrier *barrier,
2552 const char *directory,
2553 const char *console,
2554 DissectedImage *dissected_image,
2555 bool interactive,
2556 bool secondary,
2557 int pid_socket,
2558 int uuid_socket,
2559 int notify_socket,
2560 int kmsg_socket,
2561 int rtnl_socket,
2562 int uid_shift_socket,
2563 int unified_cgroup_hierarchy_socket,
2564 FDSet *fds,
2565 int netns_fd) {
2566
2567 pid_t pid;
2568 ssize_t l;
2569 int r;
2570 _cleanup_close_ int fd = -1;
2571 bool create_netns;
2572
2573 assert(barrier);
2574 assert(directory);
2575 assert(console);
2576 assert(pid_socket >= 0);
2577 assert(uuid_socket >= 0);
2578 assert(notify_socket >= 0);
2579 assert(kmsg_socket >= 0);
2580
2581 if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0)
2582 return log_error_errno(errno, "PR_SET_PDEATHSIG failed: %m");
2583
2584 if (interactive) {
2585 close_nointr(STDIN_FILENO);
2586 close_nointr(STDOUT_FILENO);
2587 close_nointr(STDERR_FILENO);
2588
2589 r = open_terminal(console, O_RDWR);
2590 if (r != STDIN_FILENO) {
2591 if (r >= 0) {
2592 safe_close(r);
2593 r = -EINVAL;
2594 }
2595
2596 return log_error_errno(r, "Failed to open console: %m");
2597 }
2598
2599 if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
2600 dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO)
2601 return log_error_errno(errno, "Failed to duplicate console: %m");
2602 }
2603
2604 r = reset_audit_loginuid();
2605 if (r < 0)
2606 return r;
2607
2608 /* Mark everything as slave, so that we still
2609 * receive mounts from the real root, but don't
2610 * propagate mounts to the real root. */
2611 r = mount_verbose(LOG_ERR, NULL, "/", NULL, MS_SLAVE|MS_REC, NULL);
2612 if (r < 0)
2613 return r;
2614
2615 if (dissected_image) {
2616 /* If we are operating on a disk image, then mount its root directory now, but leave out the rest. We
2617 * can read the UID shift from it if we need to. Further down we'll mount the rest, but then with the
2618 * uid shift known. That way we can mount VFAT file systems shifted to the right place right away. This
2619 * makes sure ESP partitions and userns are compatible. */
2620
2621 r = dissected_image_mount(dissected_image, directory, arg_uid_shift,
2622 DISSECT_IMAGE_MOUNT_ROOT_ONLY|DISSECT_IMAGE_DISCARD_ON_LOOP|(arg_read_only ? DISSECT_IMAGE_READ_ONLY : 0));
2623 if (r < 0)
2624 return r;
2625 }
2626
2627 r = determine_uid_shift(directory);
2628 if (r < 0)
2629 return r;
2630
2631 if (arg_userns_mode != USER_NAMESPACE_NO) {
2632 /* Let the parent know which UID shift we read from the image */
2633 l = send(uid_shift_socket, &arg_uid_shift, sizeof(arg_uid_shift), MSG_NOSIGNAL);
2634 if (l < 0)
2635 return log_error_errno(errno, "Failed to send UID shift: %m");
2636 if (l != sizeof(arg_uid_shift)) {
2637 log_error("Short write while sending UID shift.");
2638 return -EIO;
2639 }
2640
2641 if (arg_userns_mode == USER_NAMESPACE_PICK) {
2642 /* When we are supposed to pick the UID shift, the parent will check now whether the UID shift
2643 * we just read from the image is available. If yes, it will send the UID shift back to us, if
2644 * not it will pick a different one, and send it back to us. */
2645
2646 l = recv(uid_shift_socket, &arg_uid_shift, sizeof(arg_uid_shift), 0);
2647 if (l < 0)
2648 return log_error_errno(errno, "Failed to recv UID shift: %m");
2649 if (l != sizeof(arg_uid_shift)) {
2650 log_error("Short read while receiving UID shift.");
2651 return -EIO;
2652 }
2653 }
2654
2655 log_info("Selected user namespace base " UID_FMT " and range " UID_FMT ".", arg_uid_shift, arg_uid_range);
2656 }
2657
2658 if (dissected_image) {
2659 /* Now we know the uid shift, let's now mount everything else that might be in the image. */
2660 r = dissected_image_mount(dissected_image, directory, arg_uid_shift,
2661 DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY|DISSECT_IMAGE_DISCARD_ON_LOOP|(arg_read_only ? DISSECT_IMAGE_READ_ONLY : 0));
2662 if (r < 0)
2663 return r;
2664 }
2665
2666 if (arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN) {
2667 /* OK, we don't know yet which cgroup mode to use yet. Let's figure it out, and tell the parent. */
2668
2669 r = detect_unified_cgroup_hierarchy_from_image(directory);
2670 if (r < 0)
2671 return r;
2672
2673 l = send(unified_cgroup_hierarchy_socket, &arg_unified_cgroup_hierarchy, sizeof(arg_unified_cgroup_hierarchy), MSG_NOSIGNAL);
2674 if (l < 0)
2675 return log_error_errno(errno, "Failed to send cgroup mode: %m");
2676 if (l != sizeof(arg_unified_cgroup_hierarchy)) {
2677 log_error("Short write while sending cgroup mode: %m");
2678 return -EIO;
2679 }
2680
2681 unified_cgroup_hierarchy_socket = safe_close(unified_cgroup_hierarchy_socket);
2682 }
2683
2684 /* Turn directory into bind mount */
2685 r = mount_verbose(LOG_ERR, directory, directory, NULL, MS_BIND|MS_REC, NULL);
2686 if (r < 0)
2687 return r;
2688
2689 r = setup_pivot_root(
2690 directory,
2691 arg_pivot_root_new,
2692 arg_pivot_root_old);
2693 if (r < 0)
2694 return r;
2695
2696 r = setup_volatile(
2697 directory,
2698 arg_volatile_mode,
2699 arg_userns_mode != USER_NAMESPACE_NO,
2700 arg_uid_shift,
2701 arg_uid_range,
2702 arg_selinux_context);
2703 if (r < 0)
2704 return r;
2705
2706 r = setup_volatile_state(
2707 directory,
2708 arg_volatile_mode,
2709 arg_userns_mode != USER_NAMESPACE_NO,
2710 arg_uid_shift,
2711 arg_uid_range,
2712 arg_selinux_context);
2713 if (r < 0)
2714 return r;
2715
2716 /* Mark everything as shared so our mounts get propagated down. This is
2717 * required to make new bind mounts available in systemd services
2718 * inside the containter that create a new mount namespace.
2719 * See https://github.com/systemd/systemd/issues/3860
2720 * Further submounts (such as /dev) done after this will inherit the
2721 * shared propagation mode. */
2722 r = mount_verbose(LOG_ERR, NULL, directory, NULL, MS_SHARED|MS_REC, NULL);
2723 if (r < 0)
2724 return r;
2725
2726 r = recursive_chown(directory, arg_uid_shift, arg_uid_range);
2727 if (r < 0)
2728 return r;
2729
2730 r = base_filesystem_create(directory, arg_uid_shift, (gid_t) arg_uid_shift);
2731 if (r < 0)
2732 return r;
2733
2734 if (arg_read_only) {
2735 r = bind_remount_recursive(directory, true, NULL);
2736 if (r < 0)
2737 return log_error_errno(r, "Failed to make tree read-only: %m");
2738 }
2739
2740 r = mount_all(directory,
2741 arg_mount_settings,
2742 arg_uid_shift,
2743 arg_uid_range,
2744 arg_selinux_apifs_context);
2745 if (r < 0)
2746 return r;
2747
2748 r = copy_devnodes(directory);
2749 if (r < 0)
2750 return r;
2751
2752 dev_setup(directory, arg_uid_shift, arg_uid_shift);
2753
2754 r = setup_pts(directory);
2755 if (r < 0)
2756 return r;
2757
2758 r = setup_propagate(directory);
2759 if (r < 0)
2760 return r;
2761
2762 r = setup_dev_console(directory, console);
2763 if (r < 0)
2764 return r;
2765
2766 r = setup_keyring();
2767 if (r < 0)
2768 return r;
2769
2770 r = setup_seccomp(arg_caps_retain, arg_syscall_whitelist, arg_syscall_blacklist);
2771 if (r < 0)
2772 return r;
2773
2774 r = setup_timezone(directory);
2775 if (r < 0)
2776 return r;
2777
2778 r = setup_resolv_conf(directory);
2779 if (r < 0)
2780 return r;
2781
2782 r = setup_machine_id(directory);
2783 if (r < 0)
2784 return r;
2785
2786 r = setup_journal(directory);
2787 if (r < 0)
2788 return r;
2789
2790 r = mount_custom(
2791 directory,
2792 arg_custom_mounts,
2793 arg_n_custom_mounts,
2794 arg_userns_mode != USER_NAMESPACE_NO,
2795 arg_uid_shift,
2796 arg_uid_range,
2797 arg_selinux_apifs_context);
2798 if (r < 0)
2799 return r;
2800
2801 if (!arg_use_cgns || !cg_ns_supported()) {
2802 r = mount_cgroups(
2803 directory,
2804 arg_unified_cgroup_hierarchy,
2805 arg_userns_mode != USER_NAMESPACE_NO,
2806 arg_uid_shift,
2807 arg_uid_range,
2808 arg_selinux_apifs_context,
2809 false);
2810 if (r < 0)
2811 return r;
2812 }
2813
2814 r = mount_move_root(directory);
2815 if (r < 0)
2816 return log_error_errno(r, "Failed to move root directory: %m");
2817
2818 fd = setup_sd_notify_child();
2819 if (fd < 0)
2820 return fd;
2821
2822 create_netns = !arg_network_namespace_path && arg_private_network;
2823
2824 pid = raw_clone(SIGCHLD|CLONE_NEWNS|
2825 arg_clone_ns_flags |
2826 (create_netns ? CLONE_NEWNET : 0) |
2827 (arg_userns_mode != USER_NAMESPACE_NO ? CLONE_NEWUSER : 0));
2828 if (pid < 0)
2829 return log_error_errno(errno, "Failed to fork inner child: %m");
2830 if (pid == 0) {
2831 pid_socket = safe_close(pid_socket);
2832 uuid_socket = safe_close(uuid_socket);
2833 notify_socket = safe_close(notify_socket);
2834 uid_shift_socket = safe_close(uid_shift_socket);
2835
2836 /* The inner child has all namespaces that are
2837 * requested, so that we all are owned by the user if
2838 * user namespaces are turned on. */
2839
2840 if (arg_network_namespace_path) {
2841 r = namespace_enter(-1, -1, netns_fd, -1, -1);
2842 if (r < 0)
2843 return r;
2844 }
2845
2846 r = inner_child(barrier, directory, secondary, kmsg_socket, rtnl_socket, fds);
2847 if (r < 0)
2848 _exit(EXIT_FAILURE);
2849
2850 _exit(EXIT_SUCCESS);
2851 }
2852
2853 l = send(pid_socket, &pid, sizeof(pid), MSG_NOSIGNAL);
2854 if (l < 0)
2855 return log_error_errno(errno, "Failed to send PID: %m");
2856 if (l != sizeof(pid)) {
2857 log_error("Short write while sending PID.");
2858 return -EIO;
2859 }
2860
2861 l = send(uuid_socket, &arg_uuid, sizeof(arg_uuid), MSG_NOSIGNAL);
2862 if (l < 0)
2863 return log_error_errno(errno, "Failed to send machine ID: %m");
2864 if (l != sizeof(arg_uuid)) {
2865 log_error("Short write while sending machine ID.");
2866 return -EIO;
2867 }
2868
2869 l = send_one_fd(notify_socket, fd, 0);
2870 if (l < 0)
2871 return log_error_errno(errno, "Failed to send notify fd: %m");
2872
2873 pid_socket = safe_close(pid_socket);
2874 uuid_socket = safe_close(uuid_socket);
2875 notify_socket = safe_close(notify_socket);
2876 kmsg_socket = safe_close(kmsg_socket);
2877 rtnl_socket = safe_close(rtnl_socket);
2878 netns_fd = safe_close(netns_fd);
2879
2880 return 0;
2881 }
2882
2883 static int uid_shift_pick(uid_t *shift, LockFile *ret_lock_file) {
2884 bool tried_hashed = false;
2885 unsigned n_tries = 100;
2886 uid_t candidate;
2887 int r;
2888
2889 assert(shift);
2890 assert(ret_lock_file);
2891 assert(arg_userns_mode == USER_NAMESPACE_PICK);
2892 assert(arg_uid_range == 0x10000U);
2893
2894 candidate = *shift;
2895
2896 (void) mkdir("/run/systemd/nspawn-uid", 0755);
2897
2898 for (;;) {
2899 char lock_path[STRLEN("/run/systemd/nspawn-uid/") + DECIMAL_STR_MAX(uid_t) + 1];
2900 _cleanup_release_lock_file_ LockFile lf = LOCK_FILE_INIT;
2901
2902 if (--n_tries <= 0)
2903 return -EBUSY;
2904
2905 if (candidate < CONTAINER_UID_BASE_MIN || candidate > CONTAINER_UID_BASE_MAX)
2906 goto next;
2907 if ((candidate & UINT32_C(0xFFFF)) != 0)
2908 goto next;
2909
2910 xsprintf(lock_path, "/run/systemd/nspawn-uid/" UID_FMT, candidate);
2911 r = make_lock_file(lock_path, LOCK_EX|LOCK_NB, &lf);
2912 if (r == -EBUSY) /* Range already taken by another nspawn instance */
2913 goto next;
2914 if (r < 0)
2915 return r;
2916
2917 /* Make some superficial checks whether the range is currently known in the user database */
2918 if (getpwuid(candidate))
2919 goto next;
2920 if (getpwuid(candidate + UINT32_C(0xFFFE)))
2921 goto next;
2922 if (getgrgid(candidate))
2923 goto next;
2924 if (getgrgid(candidate + UINT32_C(0xFFFE)))
2925 goto next;
2926
2927 *ret_lock_file = lf;
2928 lf = (struct LockFile) LOCK_FILE_INIT;
2929 *shift = candidate;
2930 return 0;
2931
2932 next:
2933 if (arg_machine && !tried_hashed) {
2934 /* Try to hash the base from the container name */
2935
2936 static const uint8_t hash_key[] = {
2937 0xe1, 0x56, 0xe0, 0xf0, 0x4a, 0xf0, 0x41, 0xaf,
2938 0x96, 0x41, 0xcf, 0x41, 0x33, 0x94, 0xff, 0x72
2939 };
2940
2941 candidate = (uid_t) siphash24(arg_machine, strlen(arg_machine), hash_key);
2942
2943 tried_hashed = true;
2944 } else
2945 random_bytes(&candidate, sizeof(candidate));
2946
2947 candidate = (candidate % (CONTAINER_UID_BASE_MAX - CONTAINER_UID_BASE_MIN)) + CONTAINER_UID_BASE_MIN;
2948 candidate &= (uid_t) UINT32_C(0xFFFF0000);
2949 }
2950 }
2951
2952 static int setup_uid_map(pid_t pid) {
2953 char uid_map[STRLEN("/proc//uid_map") + DECIMAL_STR_MAX(uid_t) + 1], line[DECIMAL_STR_MAX(uid_t)*3+3+1];
2954 int r;
2955
2956 assert(pid > 1);
2957
2958 xsprintf(uid_map, "/proc/" PID_FMT "/uid_map", pid);
2959 xsprintf(line, UID_FMT " " UID_FMT " " UID_FMT "\n", 0, arg_uid_shift, arg_uid_range);
2960 r = write_string_file(uid_map, line, 0);
2961 if (r < 0)
2962 return log_error_errno(r, "Failed to write UID map: %m");
2963
2964 /* We always assign the same UID and GID ranges */
2965 xsprintf(uid_map, "/proc/" PID_FMT "/gid_map", pid);
2966 r = write_string_file(uid_map, line, 0);
2967 if (r < 0)
2968 return log_error_errno(r, "Failed to write GID map: %m");
2969
2970 return 0;
2971 }
2972
2973 static int nspawn_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
2974 char buf[NOTIFY_BUFFER_MAX+1];
2975 char *p = NULL;
2976 struct iovec iovec = {
2977 .iov_base = buf,
2978 .iov_len = sizeof(buf)-1,
2979 };
2980 union {
2981 struct cmsghdr cmsghdr;
2982 uint8_t buf[CMSG_SPACE(sizeof(struct ucred)) +
2983 CMSG_SPACE(sizeof(int) * NOTIFY_FD_MAX)];
2984 } control = {};
2985 struct msghdr msghdr = {
2986 .msg_iov = &iovec,
2987 .msg_iovlen = 1,
2988 .msg_control = &control,
2989 .msg_controllen = sizeof(control),
2990 };
2991 struct cmsghdr *cmsg;
2992 struct ucred *ucred = NULL;
2993 ssize_t n;
2994 pid_t inner_child_pid;
2995 _cleanup_strv_free_ char **tags = NULL;
2996
2997 assert(userdata);
2998
2999 inner_child_pid = PTR_TO_PID(userdata);
3000
3001 if (revents != EPOLLIN) {
3002 log_warning("Got unexpected poll event for notify fd.");
3003 return 0;
3004 }
3005
3006 n = recvmsg(fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
3007 if (n < 0) {
3008 if (IN_SET(errno, EAGAIN, EINTR))
3009 return 0;
3010
3011 return log_warning_errno(errno, "Couldn't read notification socket: %m");
3012 }
3013 cmsg_close_all(&msghdr);
3014
3015 CMSG_FOREACH(cmsg, &msghdr) {
3016 if (cmsg->cmsg_level == SOL_SOCKET &&
3017 cmsg->cmsg_type == SCM_CREDENTIALS &&
3018 cmsg->cmsg_len == CMSG_LEN(sizeof(struct ucred))) {
3019
3020 ucred = (struct ucred*) CMSG_DATA(cmsg);
3021 }
3022 }
3023
3024 if (!ucred || ucred->pid != inner_child_pid) {
3025 log_debug("Received notify message without valid credentials. Ignoring.");
3026 return 0;
3027 }
3028
3029 if ((size_t) n >= sizeof(buf)) {
3030 log_warning("Received notify message exceeded maximum size. Ignoring.");
3031 return 0;
3032 }
3033
3034 buf[n] = 0;
3035 tags = strv_split(buf, "\n\r");
3036 if (!tags)
3037 return log_oom();
3038
3039 if (strv_find(tags, "READY=1"))
3040 sd_notifyf(false, "READY=1\n");
3041
3042 p = strv_find_startswith(tags, "STATUS=");
3043 if (p)
3044 sd_notifyf(false, "STATUS=Container running: %s", p);
3045
3046 return 0;
3047 }
3048
3049 static int setup_sd_notify_parent(sd_event *event, int fd, pid_t *inner_child_pid, sd_event_source **notify_event_source) {
3050 int r;
3051
3052 r = sd_event_add_io(event, notify_event_source, fd, EPOLLIN, nspawn_dispatch_notify_fd, inner_child_pid);
3053 if (r < 0)
3054 return log_error_errno(r, "Failed to allocate notify event source: %m");
3055
3056 (void) sd_event_source_set_description(*notify_event_source, "nspawn-notify");
3057
3058 return 0;
3059 }
3060
3061 static int load_settings(void) {
3062 _cleanup_(settings_freep) Settings *settings = NULL;
3063 _cleanup_fclose_ FILE *f = NULL;
3064 _cleanup_free_ char *p = NULL;
3065 const char *fn, *i;
3066 int r;
3067
3068 /* If all settings are masked, there's no point in looking for
3069 * the settings file */
3070 if ((arg_settings_mask & _SETTINGS_MASK_ALL) == _SETTINGS_MASK_ALL)
3071 return 0;
3072
3073 fn = strjoina(arg_machine, ".nspawn");
3074
3075 /* We first look in the admin's directories in /etc and /run */
3076 FOREACH_STRING(i, "/etc/systemd/nspawn", "/run/systemd/nspawn") {
3077 _cleanup_free_ char *j = NULL;
3078
3079 j = strjoin(i, "/", fn);
3080 if (!j)
3081 return log_oom();
3082
3083 f = fopen(j, "re");
3084 if (f) {
3085 p = j;
3086 j = NULL;
3087
3088 /* By default, we trust configuration from /etc and /run */
3089 if (arg_settings_trusted < 0)
3090 arg_settings_trusted = true;
3091
3092 break;
3093 }
3094
3095 if (errno != ENOENT)
3096 return log_error_errno(errno, "Failed to open %s: %m", j);
3097 }
3098
3099 if (!f) {
3100 /* After that, let's look for a file next to the
3101 * actual image we shall boot. */
3102
3103 if (arg_image) {
3104 p = file_in_same_dir(arg_image, fn);
3105 if (!p)
3106 return log_oom();
3107 } else if (arg_directory) {
3108 p = file_in_same_dir(arg_directory, fn);
3109 if (!p)
3110 return log_oom();
3111 }
3112
3113 if (p) {
3114 f = fopen(p, "re");
3115 if (!f && errno != ENOENT)
3116 return log_error_errno(errno, "Failed to open %s: %m", p);
3117
3118 /* By default, we do not trust configuration from /var/lib/machines */
3119 if (arg_settings_trusted < 0)
3120 arg_settings_trusted = false;
3121 }
3122 }
3123
3124 if (!f)
3125 return 0;
3126
3127 log_debug("Settings are trusted: %s", yes_no(arg_settings_trusted));
3128
3129 r = settings_load(f, p, &settings);
3130 if (r < 0)
3131 return r;
3132
3133 /* Copy over bits from the settings, unless they have been
3134 * explicitly masked by command line switches. */
3135
3136 if ((arg_settings_mask & SETTING_START_MODE) == 0 &&
3137 settings->start_mode >= 0) {
3138 arg_start_mode = settings->start_mode;
3139
3140 strv_free(arg_parameters);
3141 arg_parameters = settings->parameters;
3142 settings->parameters = NULL;
3143 }
3144
3145 if ((arg_settings_mask & SETTING_PIVOT_ROOT) == 0 &&
3146 settings->pivot_root_new) {
3147 free_and_replace(arg_pivot_root_new, settings->pivot_root_new);
3148 free_and_replace(arg_pivot_root_old, settings->pivot_root_old);
3149 }
3150
3151 if ((arg_settings_mask & SETTING_WORKING_DIRECTORY) == 0 &&
3152 settings->working_directory) {
3153 free(arg_chdir);
3154 arg_chdir = settings->working_directory;
3155 settings->working_directory = NULL;
3156 }
3157
3158 if ((arg_settings_mask & SETTING_ENVIRONMENT) == 0 &&
3159 settings->environment) {
3160 strv_free(arg_setenv);
3161 arg_setenv = settings->environment;
3162 settings->environment = NULL;
3163 }
3164
3165 if ((arg_settings_mask & SETTING_USER) == 0 &&
3166 settings->user) {
3167 free(arg_user);
3168 arg_user = settings->user;
3169 settings->user = NULL;
3170 }
3171
3172 if ((arg_settings_mask & SETTING_CAPABILITY) == 0) {
3173 uint64_t plus;
3174
3175 plus = settings->capability;
3176 if (settings_private_network(settings))
3177 plus |= (1ULL << CAP_NET_ADMIN);
3178
3179 if (!arg_settings_trusted && plus != 0) {
3180 if (settings->capability != 0)
3181 log_warning("Ignoring Capability= setting, file %s is not trusted.", p);
3182 } else
3183 arg_caps_retain |= plus;
3184
3185 arg_caps_retain &= ~settings->drop_capability;
3186 }
3187
3188 if ((arg_settings_mask & SETTING_KILL_SIGNAL) == 0 &&
3189 settings->kill_signal > 0)
3190 arg_kill_signal = settings->kill_signal;
3191
3192 if ((arg_settings_mask & SETTING_PERSONALITY) == 0 &&
3193 settings->personality != PERSONALITY_INVALID)
3194 arg_personality = settings->personality;
3195
3196 if ((arg_settings_mask & SETTING_MACHINE_ID) == 0 &&
3197 !sd_id128_is_null(settings->machine_id)) {
3198
3199 if (!arg_settings_trusted)
3200 log_warning("Ignoring MachineID= setting, file %s is not trusted.", p);
3201 else
3202 arg_uuid = settings->machine_id;
3203 }
3204
3205 if ((arg_settings_mask & SETTING_READ_ONLY) == 0 &&
3206 settings->read_only >= 0)
3207 arg_read_only = settings->read_only;
3208
3209 if ((arg_settings_mask & SETTING_VOLATILE_MODE) == 0 &&
3210 settings->volatile_mode != _VOLATILE_MODE_INVALID)
3211 arg_volatile_mode = settings->volatile_mode;
3212
3213 if ((arg_settings_mask & SETTING_CUSTOM_MOUNTS) == 0 &&
3214 settings->n_custom_mounts > 0) {
3215
3216 if (!arg_settings_trusted)
3217 log_warning("Ignoring TemporaryFileSystem=, Bind= and BindReadOnly= settings, file %s is not trusted.", p);
3218 else {
3219 custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts);
3220 arg_custom_mounts = settings->custom_mounts;
3221 arg_n_custom_mounts = settings->n_custom_mounts;
3222
3223 settings->custom_mounts = NULL;
3224 settings->n_custom_mounts = 0;
3225 }
3226 }
3227
3228 if ((arg_settings_mask & SETTING_NETWORK) == 0 &&
3229 (settings->private_network >= 0 ||
3230 settings->network_veth >= 0 ||
3231 settings->network_bridge ||
3232 settings->network_zone ||
3233 settings->network_interfaces ||
3234 settings->network_macvlan ||
3235 settings->network_ipvlan ||
3236 settings->network_veth_extra)) {
3237
3238 if (!arg_settings_trusted)
3239 log_warning("Ignoring network settings, file %s is not trusted.", p);
3240 else {
3241 arg_network_veth = settings_network_veth(settings);
3242 arg_private_network = settings_private_network(settings);
3243
3244 strv_free(arg_network_interfaces);
3245 arg_network_interfaces = settings->network_interfaces;
3246 settings->network_interfaces = NULL;
3247
3248 strv_free(arg_network_macvlan);
3249 arg_network_macvlan = settings->network_macvlan;
3250 settings->network_macvlan = NULL;
3251
3252 strv_free(arg_network_ipvlan);
3253 arg_network_ipvlan = settings->network_ipvlan;
3254 settings->network_ipvlan = NULL;
3255
3256 strv_free(arg_network_veth_extra);
3257 arg_network_veth_extra = settings->network_veth_extra;
3258 settings->network_veth_extra = NULL;
3259
3260 free(arg_network_bridge);
3261 arg_network_bridge = settings->network_bridge;
3262 settings->network_bridge = NULL;
3263
3264 free(arg_network_zone);
3265 arg_network_zone = settings->network_zone;
3266 settings->network_zone = NULL;
3267 }
3268 }
3269
3270 if ((arg_settings_mask & SETTING_EXPOSE_PORTS) == 0 &&
3271 settings->expose_ports) {
3272
3273 if (!arg_settings_trusted)
3274 log_warning("Ignoring Port= setting, file %s is not trusted.", p);
3275 else {
3276 expose_port_free_all(arg_expose_ports);
3277 arg_expose_ports = settings->expose_ports;
3278 settings->expose_ports = NULL;
3279 }
3280 }
3281
3282 if ((arg_settings_mask & SETTING_USERNS) == 0 &&
3283 settings->userns_mode != _USER_NAMESPACE_MODE_INVALID) {
3284
3285 if (!arg_settings_trusted)
3286 log_warning("Ignoring PrivateUsers= and PrivateUsersChown= settings, file %s is not trusted.", p);
3287 else {
3288 arg_userns_mode = settings->userns_mode;
3289 arg_uid_shift = settings->uid_shift;
3290 arg_uid_range = settings->uid_range;
3291 arg_userns_chown = settings->userns_chown;
3292 }
3293 }
3294
3295 if ((arg_settings_mask & SETTING_NOTIFY_READY) == 0)
3296 arg_notify_ready = settings->notify_ready;
3297
3298 if ((arg_settings_mask & SETTING_SYSCALL_FILTER) == 0) {
3299
3300 if (!arg_settings_trusted && !strv_isempty(arg_syscall_whitelist))
3301 log_warning("Ignoring SystemCallFilter= settings, file %s is not trusted.", p);
3302 else {
3303 strv_free(arg_syscall_whitelist);
3304 strv_free(arg_syscall_blacklist);
3305
3306 arg_syscall_whitelist = settings->syscall_whitelist;
3307 arg_syscall_blacklist = settings->syscall_blacklist;
3308
3309 settings->syscall_whitelist = settings->syscall_blacklist = NULL;
3310 }
3311 }
3312
3313 return 0;
3314 }
3315
3316 static int run(int master,
3317 const char* console,
3318 DissectedImage *dissected_image,
3319 bool interactive,
3320 bool secondary,
3321 FDSet *fds,
3322 char veth_name[IFNAMSIZ], bool *veth_created,
3323 union in_addr_union *exposed,
3324 pid_t *pid, int *ret) {
3325
3326 static const struct sigaction sa = {
3327 .sa_handler = nop_signal_handler,
3328 .sa_flags = SA_NOCLDSTOP|SA_RESTART,
3329 };
3330
3331 _cleanup_release_lock_file_ LockFile uid_shift_lock = LOCK_FILE_INIT;
3332 _cleanup_close_ int etc_passwd_lock = -1;
3333 _cleanup_close_pair_ int
3334 kmsg_socket_pair[2] = { -1, -1 },
3335 rtnl_socket_pair[2] = { -1, -1 },
3336 pid_socket_pair[2] = { -1, -1 },
3337 uuid_socket_pair[2] = { -1, -1 },
3338 notify_socket_pair[2] = { -1, -1 },
3339 uid_shift_socket_pair[2] = { -1, -1 },
3340 unified_cgroup_hierarchy_socket_pair[2] = { -1, -1};
3341
3342 _cleanup_close_ int notify_socket= -1;
3343 _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
3344 _cleanup_(sd_event_source_unrefp) sd_event_source *notify_event_source = NULL;
3345 _cleanup_(sd_event_unrefp) sd_event *event = NULL;
3346 _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
3347 _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
3348 _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
3349 ContainerStatus container_status = 0;
3350 char last_char = 0;
3351 int ifi = 0, r;
3352 ssize_t l;
3353 sigset_t mask_chld;
3354 _cleanup_close_ int netns_fd = -1;
3355
3356 assert_se(sigemptyset(&mask_chld) == 0);
3357 assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
3358
3359 if (arg_userns_mode == USER_NAMESPACE_PICK) {
3360 /* When we shall pick the UID/GID range, let's first lock /etc/passwd, so that we can safely
3361 * check with getpwuid() if the specific user already exists. Note that /etc might be
3362 * read-only, in which case this will fail with EROFS. But that's really OK, as in that case we
3363 * can be reasonably sure that no users are going to be added. Note that getpwuid() checks are
3364 * really just an extra safety net. We kinda assume that the UID range we allocate from is
3365 * really ours. */
3366
3367 etc_passwd_lock = take_etc_passwd_lock(NULL);
3368 if (etc_passwd_lock < 0 && etc_passwd_lock != -EROFS)
3369 return log_error_errno(etc_passwd_lock, "Failed to take /etc/passwd lock: %m");
3370 }
3371
3372 r = barrier_create(&barrier);
3373 if (r < 0)
3374 return log_error_errno(r, "Cannot initialize IPC barrier: %m");
3375
3376 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0)
3377 return log_error_errno(errno, "Failed to create kmsg socket pair: %m");
3378
3379 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, rtnl_socket_pair) < 0)
3380 return log_error_errno(errno, "Failed to create rtnl socket pair: %m");
3381
3382 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pid_socket_pair) < 0)
3383 return log_error_errno(errno, "Failed to create pid socket pair: %m");
3384
3385 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uuid_socket_pair) < 0)
3386 return log_error_errno(errno, "Failed to create id socket pair: %m");
3387
3388 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, notify_socket_pair) < 0)
3389 return log_error_errno(errno, "Failed to create notify socket pair: %m");
3390
3391 if (arg_userns_mode != USER_NAMESPACE_NO)
3392 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uid_shift_socket_pair) < 0)
3393 return log_error_errno(errno, "Failed to create uid shift socket pair: %m");
3394
3395 if (arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN)
3396 if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, unified_cgroup_hierarchy_socket_pair) < 0)
3397 return log_error_errno(errno, "Failed to create unified cgroup socket pair: %m");
3398
3399 /* Child can be killed before execv(), so handle SIGCHLD in order to interrupt
3400 * parent's blocking calls and give it a chance to call wait() and terminate. */
3401 r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL);
3402 if (r < 0)
3403 return log_error_errno(errno, "Failed to change the signal mask: %m");
3404
3405 r = sigaction(SIGCHLD, &sa, NULL);
3406 if (r < 0)
3407 return log_error_errno(errno, "Failed to install SIGCHLD handler: %m");
3408
3409 if (arg_network_namespace_path) {
3410 netns_fd = open(arg_network_namespace_path, O_RDONLY|O_NOCTTY|O_CLOEXEC);
3411 if (netns_fd < 0)
3412 return log_error_errno(errno, "Cannot open file %s: %m", arg_network_namespace_path);
3413
3414 r = fd_is_network_ns(netns_fd);
3415 if (r < 0 && r != -ENOTTY)
3416 return log_error_errno(r, "Failed to check %s fs type: %m", arg_network_namespace_path);
3417 if (r == 0) {
3418 log_error("Path %s doesn't refer to a network namespace", arg_network_namespace_path);
3419 return -EINVAL;
3420 }
3421 }
3422
3423 *pid = raw_clone(SIGCHLD|CLONE_NEWNS);
3424 if (*pid < 0)
3425 return log_error_errno(errno, "clone() failed%s: %m",
3426 errno == EINVAL ?
3427 ", do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in)" : "");
3428
3429 if (*pid == 0) {
3430 /* The outer child only has a file system namespace. */
3431 barrier_set_role(&barrier, BARRIER_CHILD);
3432
3433 master = safe_close(master);
3434
3435 kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]);
3436 rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
3437 pid_socket_pair[0] = safe_close(pid_socket_pair[0]);
3438 uuid_socket_pair[0] = safe_close(uuid_socket_pair[0]);
3439 notify_socket_pair[0] = safe_close(notify_socket_pair[0]);
3440 uid_shift_socket_pair[0] = safe_close(uid_shift_socket_pair[0]);
3441 unified_cgroup_hierarchy_socket_pair[0] = safe_close(unified_cgroup_hierarchy_socket_pair[0]);
3442
3443 (void) reset_all_signal_handlers();
3444 (void) reset_signal_mask();
3445
3446 r = outer_child(&barrier,
3447 arg_directory,
3448 console,
3449 dissected_image,
3450 interactive,
3451 secondary,
3452 pid_socket_pair[1],
3453 uuid_socket_pair[1],
3454 notify_socket_pair[1],
3455 kmsg_socket_pair[1],
3456 rtnl_socket_pair[1],
3457 uid_shift_socket_pair[1],
3458 unified_cgroup_hierarchy_socket_pair[1],
3459 fds,
3460 netns_fd);
3461 if (r < 0)
3462 _exit(EXIT_FAILURE);
3463
3464 _exit(EXIT_SUCCESS);
3465 }
3466
3467 barrier_set_role(&barrier, BARRIER_PARENT);
3468
3469 fds = fdset_free(fds);
3470
3471 kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
3472 rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]);
3473 pid_socket_pair[1] = safe_close(pid_socket_pair[1]);
3474 uuid_socket_pair[1] = safe_close(uuid_socket_pair[1]);
3475 notify_socket_pair[1] = safe_close(notify_socket_pair[1]);
3476 uid_shift_socket_pair[1] = safe_close(uid_shift_socket_pair[1]);
3477 unified_cgroup_hierarchy_socket_pair[1] = safe_close(unified_cgroup_hierarchy_socket_pair[1]);
3478
3479 if (arg_userns_mode != USER_NAMESPACE_NO) {
3480 /* The child just let us know the UID shift it might have read from the image. */
3481 l = recv(uid_shift_socket_pair[0], &arg_uid_shift, sizeof arg_uid_shift, 0);
3482 if (l < 0)
3483 return log_error_errno(errno, "Failed to read UID shift: %m");
3484 if (l != sizeof arg_uid_shift) {
3485 log_error("Short read while reading UID shift.");
3486 return -EIO;
3487 }
3488
3489 if (arg_userns_mode == USER_NAMESPACE_PICK) {
3490 /* If we are supposed to pick the UID shift, let's try to use the shift read from the
3491 * image, but if that's already in use, pick a new one, and report back to the child,
3492 * which one we now picked. */
3493
3494 r = uid_shift_pick(&arg_uid_shift, &uid_shift_lock);
3495 if (r < 0)
3496 return log_error_errno(r, "Failed to pick suitable UID/GID range: %m");
3497
3498 l = send(uid_shift_socket_pair[0], &arg_uid_shift, sizeof arg_uid_shift, MSG_NOSIGNAL);
3499 if (l < 0)
3500 return log_error_errno(errno, "Failed to send UID shift: %m");
3501 if (l != sizeof arg_uid_shift) {
3502 log_error("Short write while writing UID shift.");
3503 return -EIO;
3504 }
3505 }
3506 }
3507
3508 if (arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN) {
3509 /* The child let us know the support cgroup mode it might have read from the image. */
3510 l = recv(unified_cgroup_hierarchy_socket_pair[0], &arg_unified_cgroup_hierarchy, sizeof(arg_unified_cgroup_hierarchy), 0);
3511 if (l < 0)
3512 return log_error_errno(errno, "Failed to read cgroup mode: %m");
3513 if (l != sizeof(arg_unified_cgroup_hierarchy)) {
3514 log_error("Short read while reading cgroup mode.");
3515 return -EIO;
3516 }
3517 }
3518
3519 /* Wait for the outer child. */
3520 r = wait_for_terminate_and_check("(sd-namespace)", *pid, WAIT_LOG_ABNORMAL);
3521 if (r < 0)
3522 return r;
3523 if (r != EXIT_SUCCESS)
3524 return -EIO;
3525
3526 /* And now retrieve the PID of the inner child. */
3527 l = recv(pid_socket_pair[0], pid, sizeof *pid, 0);
3528 if (l < 0)
3529 return log_error_errno(errno, "Failed to read inner child PID: %m");
3530 if (l != sizeof *pid) {
3531 log_error("Short read while reading inner child PID.");
3532 return -EIO;
3533 }
3534
3535 /* We also retrieve container UUID in case it was generated by outer child */
3536 l = recv(uuid_socket_pair[0], &arg_uuid, sizeof arg_uuid, 0);
3537 if (l < 0)
3538 return log_error_errno(errno, "Failed to read container machine ID: %m");
3539 if (l != sizeof(arg_uuid)) {
3540 log_error("Short read while reading container machined ID.");
3541 return -EIO;
3542 }
3543
3544 /* We also retrieve the socket used for notifications generated by outer child */
3545 notify_socket = receive_one_fd(notify_socket_pair[0], 0);
3546 if (notify_socket < 0)
3547 return log_error_errno(notify_socket,
3548 "Failed to receive notification socket from the outer child: %m");
3549
3550 log_debug("Init process invoked as PID "PID_FMT, *pid);
3551
3552 if (arg_userns_mode != USER_NAMESPACE_NO) {
3553 if (!barrier_place_and_sync(&barrier)) { /* #1 */
3554 log_error("Child died too early.");
3555 return -ESRCH;
3556 }
3557
3558 r = setup_uid_map(*pid);
3559 if (r < 0)
3560 return r;
3561
3562 (void) barrier_place(&barrier); /* #2 */
3563 }
3564
3565 if (arg_private_network) {
3566
3567 r = move_network_interfaces(*pid, arg_network_interfaces);
3568 if (r < 0)
3569 return r;
3570
3571 if (arg_network_veth) {
3572 r = setup_veth(arg_machine, *pid, veth_name,
3573 arg_network_bridge || arg_network_zone);
3574 if (r < 0)
3575 return r;
3576 else if (r > 0)
3577 ifi = r;
3578
3579 if (arg_network_bridge) {
3580 /* Add the interface to a bridge */
3581 r = setup_bridge(veth_name, arg_network_bridge, false);
3582 if (r < 0)
3583 return r;
3584 if (r > 0)
3585 ifi = r;
3586 } else if (arg_network_zone) {
3587 /* Add the interface to a bridge, possibly creating it */
3588 r = setup_bridge(veth_name, arg_network_zone, true);
3589 if (r < 0)
3590 return r;
3591 if (r > 0)
3592 ifi = r;
3593 }
3594 }
3595
3596 r = setup_veth_extra(arg_machine, *pid, arg_network_veth_extra);
3597 if (r < 0)
3598 return r;
3599
3600 /* We created the primary and extra veth links now; let's remember this, so that we know to
3601 remove them later on. Note that we don't bother with removing veth links that were created
3602 here when their setup failed half-way, because in that case the kernel should be able to
3603 remove them on its own, since they cannot be referenced by anything yet. */
3604 *veth_created = true;
3605
3606 r = setup_macvlan(arg_machine, *pid, arg_network_macvlan);
3607 if (r < 0)
3608 return r;
3609
3610 r = setup_ipvlan(arg_machine, *pid, arg_network_ipvlan);
3611 if (r < 0)
3612 return r;
3613 }
3614
3615 if (arg_register || !arg_keep_unit) {
3616 r = sd_bus_default_system(&bus);
3617 if (r < 0)
3618 return log_error_errno(r, "Failed to open system bus: %m");
3619 }
3620
3621 if (!arg_keep_unit) {
3622 /* When a new scope is created for this container, then we'll be registered as its controller, in which
3623 * case PID 1 will send us a friendly RequestStop signal, when it is asked to terminate the
3624 * scope. Let's hook into that, and cleanly shut down the container, and print a friendly message. */
3625
3626 r = sd_bus_match_signal_async(
3627 bus,
3628 NULL,
3629 "org.freedesktop.systemd1",
3630 NULL,
3631 "org.freedesktop.systemd1.Scope",
3632 "RequestStop",
3633 on_request_stop, NULL, PID_TO_PTR(*pid));
3634 if (r < 0)
3635 return log_error_errno(r, "Failed to request RequestStop match: %m");
3636 }
3637
3638 if (arg_register) {
3639
3640 r = register_machine(
3641 bus,
3642 arg_machine,
3643 *pid,
3644 arg_directory,
3645 arg_uuid,
3646 ifi,
3647 arg_slice,
3648 arg_custom_mounts, arg_n_custom_mounts,
3649 arg_kill_signal,
3650 arg_property,
3651 arg_keep_unit,
3652 arg_container_service_name);
3653 if (r < 0)
3654 return r;
3655
3656 } else if (!arg_keep_unit) {
3657
3658 r = allocate_scope(
3659 bus,
3660 arg_machine,
3661 *pid,
3662 arg_slice,
3663 arg_custom_mounts, arg_n_custom_mounts,
3664 arg_kill_signal,
3665 arg_property);
3666 if (r < 0)
3667 return r;
3668
3669 } else if (arg_slice || arg_property)
3670 log_notice("Machine and scope registration turned off, --slice= and --property= settings will have no effect.");
3671
3672 r = sync_cgroup(*pid, arg_unified_cgroup_hierarchy, arg_uid_shift);
3673 if (r < 0)
3674 return r;
3675
3676 if (arg_keep_unit) {
3677 r = create_subcgroup(*pid, arg_unified_cgroup_hierarchy);
3678 if (r < 0)
3679 return r;
3680 }
3681
3682 r = chown_cgroup(*pid, arg_unified_cgroup_hierarchy, arg_uid_shift);
3683 if (r < 0)
3684 return r;
3685
3686 /* Notify the child that the parent is ready with all
3687 * its setup (including cgroup-ification), and that
3688 * the child can now hand over control to the code to
3689 * run inside the container. */
3690 (void) barrier_place(&barrier); /* #3 */
3691
3692 /* Block SIGCHLD here, before notifying child.
3693 * process_pty() will handle it with the other signals. */
3694 assert_se(sigprocmask(SIG_BLOCK, &mask_chld, NULL) >= 0);
3695
3696 /* Reset signal to default */
3697 r = default_signals(SIGCHLD, -1);
3698 if (r < 0)
3699 return log_error_errno(r, "Failed to reset SIGCHLD: %m");
3700
3701 r = sd_event_new(&event);
3702 if (r < 0)
3703 return log_error_errno(r, "Failed to get default event source: %m");
3704
3705 (void) sd_event_set_watchdog(event, true);
3706
3707 if (bus) {
3708 r = sd_bus_attach_event(bus, event, 0);
3709 if (r < 0)
3710 return log_error_errno(r, "Failed to attach bus to event loop: %m");
3711 }
3712
3713 r = setup_sd_notify_parent(event, notify_socket, PID_TO_PTR(*pid), &notify_event_source);
3714 if (r < 0)
3715 return r;
3716
3717 /* Let the child know that we are ready and wait that the child is completely ready now. */
3718 if (!barrier_place_and_sync(&barrier)) { /* #4 */
3719 log_error("Child died too early.");
3720 return -ESRCH;
3721 }
3722
3723 /* At this point we have made use of the UID we picked, and thus nss-mymachines
3724 * will make them appear in getpwuid(), thus we can release the /etc/passwd lock. */
3725 etc_passwd_lock = safe_close(etc_passwd_lock);
3726
3727 sd_notifyf(false,
3728 "STATUS=Container running.\n"
3729 "X_NSPAWN_LEADER_PID=" PID_FMT, *pid);
3730 if (!arg_notify_ready)
3731 sd_notify(false, "READY=1\n");
3732
3733 if (arg_kill_signal > 0) {
3734 /* Try to kill the init system on SIGINT or SIGTERM */
3735 sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(*pid));
3736 sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(*pid));
3737 } else {
3738 /* Immediately exit */
3739 sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
3740 sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
3741 }
3742
3743 /* Exit when the child exits */
3744 sd_event_add_signal(event, NULL, SIGCHLD, on_sigchld, PID_TO_PTR(*pid));
3745
3746 if (arg_expose_ports) {
3747 r = expose_port_watch_rtnl(event, rtnl_socket_pair[0], on_address_change, exposed, &rtnl);
3748 if (r < 0)
3749 return r;
3750
3751 (void) expose_port_execute(rtnl, arg_expose_ports, exposed);
3752 }
3753
3754 rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
3755
3756 r = pty_forward_new(event, master,
3757 PTY_FORWARD_IGNORE_VHANGUP | (interactive ? 0 : PTY_FORWARD_READ_ONLY),
3758 &forward);
3759 if (r < 0)
3760 return log_error_errno(r, "Failed to create PTY forwarder: %m");
3761
3762 r = sd_event_loop(event);
3763 if (r < 0)
3764 return log_error_errno(r, "Failed to run event loop: %m");
3765
3766 pty_forward_get_last_char(forward, &last_char);
3767
3768 forward = pty_forward_free(forward);
3769
3770 if (!arg_quiet && last_char != '\n')
3771 putc('\n', stdout);
3772
3773 /* Kill if it is not dead yet anyway */
3774 if (arg_register && !arg_keep_unit && bus)
3775 terminate_machine(bus, *pid);
3776
3777 /* Normally redundant, but better safe than sorry */
3778 (void) kill(*pid, SIGKILL);
3779
3780 r = wait_for_container(*pid, &container_status);
3781 *pid = 0;
3782
3783 if (r < 0)
3784 /* We failed to wait for the container, or the container exited abnormally. */
3785 return r;
3786 if (r > 0 || container_status == CONTAINER_TERMINATED) {
3787 /* r > 0 → The container exited with a non-zero status.
3788 * As a special case, we need to replace 133 with a different value,
3789 * because 133 is special-cased in the service file to reboot the container.
3790 * otherwise → The container exited with zero status and a reboot was not requested.
3791 */
3792 if (r == EXIT_FORCE_RESTART)
3793 r = EXIT_FAILURE; /* replace 133 with the general failure code */
3794 *ret = r;
3795 return 0; /* finito */
3796 }
3797
3798 /* CONTAINER_REBOOTED, loop again */
3799
3800 if (arg_keep_unit) {
3801 /* Special handling if we are running as a service: instead of simply
3802 * restarting the machine we want to restart the entire service, so let's
3803 * inform systemd about this with the special exit code 133. The service
3804 * file uses RestartForceExitStatus=133 so that this results in a full
3805 * nspawn restart. This is necessary since we might have cgroup parameters
3806 * set we want to have flushed out. */
3807 *ret = EXIT_FORCE_RESTART;
3808 return 0; /* finito */
3809 }
3810
3811 expose_port_flush(arg_expose_ports, exposed);
3812
3813 (void) remove_veth_links(veth_name, arg_network_veth_extra);
3814 *veth_created = false;
3815 return 1; /* loop again */
3816 }
3817
3818 int main(int argc, char *argv[]) {
3819
3820 _cleanup_free_ char *console = NULL;
3821 _cleanup_close_ int master = -1;
3822 _cleanup_fdset_free_ FDSet *fds = NULL;
3823 int r, n_fd_passed, ret = EXIT_SUCCESS;
3824 char veth_name[IFNAMSIZ] = "";
3825 bool secondary = false, remove_directory = false, remove_image = false;
3826 pid_t pid = 0;
3827 union in_addr_union exposed = {};
3828 _cleanup_release_lock_file_ LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT;
3829 bool interactive, veth_created = false, remove_tmprootdir = false;
3830 char tmprootdir[] = "/tmp/nspawn-root-XXXXXX";
3831 _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
3832 _cleanup_(decrypted_image_unrefp) DecryptedImage *decrypted_image = NULL;
3833 _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL;
3834
3835 log_parse_environment();
3836 log_open();
3837
3838 /* Make sure rename_process() in the stub init process can work */
3839 saved_argv = argv;
3840 saved_argc = argc;
3841
3842 r = parse_argv(argc, argv);
3843 if (r <= 0)
3844 goto finish;
3845
3846 r = must_be_root();
3847 if (r < 0)
3848 goto finish;
3849
3850 r = determine_names();
3851 if (r < 0)
3852 goto finish;
3853
3854 r = load_settings();
3855 if (r < 0)
3856 goto finish;
3857
3858 r = verify_arguments();
3859 if (r < 0)
3860 goto finish;
3861
3862 r = detect_unified_cgroup_hierarchy_from_environment();
3863 if (r < 0)
3864 goto finish;
3865
3866 n_fd_passed = sd_listen_fds(false);
3867 if (n_fd_passed > 0) {
3868 r = fdset_new_listen_fds(&fds, false);
3869 if (r < 0) {
3870 log_error_errno(r, "Failed to collect file descriptors: %m");
3871 goto finish;
3872 }
3873 }
3874
3875 if (arg_directory) {
3876 assert(!arg_image);
3877
3878 if (path_equal(arg_directory, "/") && !arg_ephemeral) {
3879 log_error("Spawning container on root directory is not supported. Consider using --ephemeral.");
3880 r = -EINVAL;
3881 goto finish;
3882 }
3883
3884 if (arg_ephemeral) {
3885 _cleanup_free_ char *np = NULL;
3886
3887 r = chase_symlinks_and_update(&arg_directory, 0);
3888 if (r < 0)
3889 goto finish;
3890
3891 /* If the specified path is a mount point we
3892 * generate the new snapshot immediately
3893 * inside it under a random name. However if
3894 * the specified is not a mount point we
3895 * create the new snapshot in the parent
3896 * directory, just next to it. */
3897 r = path_is_mount_point(arg_directory, NULL, 0);
3898 if (r < 0) {
3899 log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory);
3900 goto finish;
3901 }
3902 if (r > 0)
3903 r = tempfn_random_child(arg_directory, "machine.", &np);
3904 else
3905 r = tempfn_random(arg_directory, "machine.", &np);
3906 if (r < 0) {
3907 log_error_errno(r, "Failed to generate name for directory snapshot: %m");
3908 goto finish;
3909 }
3910
3911 r = image_path_lock(np, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
3912 if (r < 0) {
3913 log_error_errno(r, "Failed to lock %s: %m", np);
3914 goto finish;
3915 }
3916
3917 r = btrfs_subvol_snapshot(arg_directory, np,
3918 (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
3919 BTRFS_SNAPSHOT_FALLBACK_COPY |
3920 BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
3921 BTRFS_SNAPSHOT_RECURSIVE |
3922 BTRFS_SNAPSHOT_QUOTA);
3923 if (r < 0) {
3924 log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory);
3925 goto finish;
3926 }
3927
3928 free(arg_directory);
3929 arg_directory = np;
3930 np = NULL;
3931
3932 remove_directory = true;
3933
3934 } else {
3935 r = chase_symlinks_and_update(&arg_directory, arg_template ? CHASE_NONEXISTENT : 0);
3936 if (r < 0)
3937 goto finish;
3938
3939 r = image_path_lock(arg_directory, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
3940 if (r == -EBUSY) {
3941 log_error_errno(r, "Directory tree %s is currently busy.", arg_directory);
3942 goto finish;
3943 }
3944 if (r < 0) {
3945 log_error_errno(r, "Failed to lock %s: %m", arg_directory);
3946 goto finish;
3947 }
3948
3949 if (arg_template) {
3950 r = chase_symlinks_and_update(&arg_template, 0);
3951 if (r < 0)
3952 goto finish;
3953
3954 r = btrfs_subvol_snapshot(arg_template, arg_directory,
3955 (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
3956 BTRFS_SNAPSHOT_FALLBACK_COPY |
3957 BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
3958 BTRFS_SNAPSHOT_FALLBACK_IMMUTABLE |
3959 BTRFS_SNAPSHOT_RECURSIVE |
3960 BTRFS_SNAPSHOT_QUOTA);
3961 if (r == -EEXIST) {
3962 if (!arg_quiet)
3963 log_info("Directory %s already exists, not populating from template %s.", arg_directory, arg_template);
3964 } else if (r < 0) {
3965 log_error_errno(r, "Couldn't create snapshot %s from %s: %m", arg_directory, arg_template);
3966 goto finish;
3967 } else {
3968 if (!arg_quiet)
3969 log_info("Populated %s from template %s.", arg_directory, arg_template);
3970 }
3971 }
3972 }
3973
3974 if (arg_start_mode == START_BOOT) {
3975 if (path_is_os_tree(arg_directory) <= 0) {
3976 log_error("Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", arg_directory);
3977 r = -EINVAL;
3978 goto finish;
3979 }
3980 } else {
3981 const char *p;
3982
3983 p = strjoina(arg_directory, "/usr/");
3984 if (laccess(p, F_OK) < 0) {
3985 log_error("Directory %s doesn't look like it has an OS tree. Refusing.", arg_directory);
3986 r = -EINVAL;
3987 goto finish;
3988 }
3989 }
3990
3991 } else {
3992 assert(arg_image);
3993 assert(!arg_template);
3994
3995 r = chase_symlinks_and_update(&arg_image, 0);
3996 if (r < 0)
3997 goto finish;
3998
3999 if (arg_ephemeral) {
4000 _cleanup_free_ char *np = NULL;
4001
4002 r = tempfn_random(arg_image, "machine.", &np);
4003 if (r < 0) {
4004 log_error_errno(r, "Failed to generate name for image snapshot: %m");
4005 goto finish;
4006 }
4007
4008 r = image_path_lock(np, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
4009 if (r < 0) {
4010 r = log_error_errno(r, "Failed to create image lock: %m");
4011 goto finish;
4012 }
4013
4014 r = copy_file(arg_image, np, O_EXCL, arg_read_only ? 0400 : 0600, FS_NOCOW_FL, COPY_REFLINK);
4015 if (r < 0) {
4016 r = log_error_errno(r, "Failed to copy image file: %m");
4017 goto finish;
4018 }
4019
4020 free(arg_image);
4021 arg_image = np;
4022 np = NULL;
4023
4024 remove_image = true;
4025 } else {
4026 r = image_path_lock(arg_image, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
4027 if (r == -EBUSY) {
4028 r = log_error_errno(r, "Disk image %s is currently busy.", arg_image);
4029 goto finish;
4030 }
4031 if (r < 0) {
4032 r = log_error_errno(r, "Failed to create image lock: %m");
4033 goto finish;
4034 }
4035
4036 if (!arg_root_hash) {
4037 r = root_hash_load(arg_image, &arg_root_hash, &arg_root_hash_size);
4038 if (r < 0) {
4039 log_error_errno(r, "Failed to load root hash file for %s: %m", arg_image);
4040 goto finish;
4041 }
4042 }
4043 }
4044
4045 if (!mkdtemp(tmprootdir)) {
4046 r = log_error_errno(errno, "Failed to create temporary directory: %m");
4047 goto finish;
4048 }
4049
4050 remove_tmprootdir = true;
4051
4052 arg_directory = strdup(tmprootdir);
4053 if (!arg_directory) {
4054 r = log_oom();
4055 goto finish;
4056 }
4057
4058 r = loop_device_make_by_path(arg_image, arg_read_only ? O_RDONLY : O_RDWR, &loop);
4059 if (r < 0) {
4060 log_error_errno(r, "Failed to set up loopback block device: %m");
4061 goto finish;
4062 }
4063
4064 r = dissect_image(
4065 loop->fd,
4066 arg_root_hash, arg_root_hash_size,
4067 DISSECT_IMAGE_REQUIRE_ROOT,
4068 &dissected_image);
4069 if (r == -ENOPKG) {
4070 log_error_errno(r, "Could not find a suitable file system or partition table in image: %s", arg_image);
4071
4072 log_notice("Note that the disk image needs to\n"
4073 " a) either contain only a single MBR partition of type 0x83 that is marked bootable\n"
4074 " b) or contain a single GPT partition of type 0FC63DAF-8483-4772-8E79-3D69D8477DE4\n"
4075 " c) or follow http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/\n"
4076 " d) or contain a file system without a partition table\n"
4077 "in order to be bootable with systemd-nspawn.");
4078 goto finish;
4079 }
4080 if (r == -EADDRNOTAVAIL) {
4081 log_error_errno(r, "No root partition for specified root hash found.");
4082 goto finish;
4083 }
4084 if (r == -EOPNOTSUPP) {
4085 log_error_errno(r, "--image= is not supported, compiled without blkid support.");
4086 goto finish;
4087 }
4088 if (r == -EPROTONOSUPPORT) {
4089 log_error_errno(r, "Device is loopback block device with partition scanning turned off, please turn it on.");
4090 goto finish;
4091 }
4092 if (r < 0) {
4093 log_error_errno(r, "Failed to dissect image: %m");
4094 goto finish;
4095 }
4096
4097 if (!arg_root_hash && dissected_image->can_verity)
4098 log_notice("Note: image %s contains verity information, but no root hash specified! Proceeding without integrity checking.", arg_image);
4099
4100 r = dissected_image_decrypt_interactively(dissected_image, NULL, arg_root_hash, arg_root_hash_size, 0, &decrypted_image);
4101 if (r < 0)
4102 goto finish;
4103
4104 /* Now that we mounted the image, let's try to remove it again, if it is ephemeral */
4105 if (remove_image && unlink(arg_image) >= 0)
4106 remove_image = false;
4107 }
4108
4109 r = custom_mount_prepare_all(arg_directory, arg_custom_mounts, arg_n_custom_mounts);
4110 if (r < 0)
4111 goto finish;
4112
4113 interactive =
4114 isatty(STDIN_FILENO) > 0 &&
4115 isatty(STDOUT_FILENO) > 0;
4116
4117 master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY);
4118 if (master < 0) {
4119 r = log_error_errno(errno, "Failed to acquire pseudo tty: %m");
4120 goto finish;
4121 }
4122
4123 r = ptsname_malloc(master, &console);
4124 if (r < 0) {
4125 r = log_error_errno(r, "Failed to determine tty name: %m");
4126 goto finish;
4127 }
4128
4129 if (arg_selinux_apifs_context) {
4130 r = mac_selinux_apply(console, arg_selinux_apifs_context);
4131 if (r < 0)
4132 goto finish;
4133 }
4134
4135 if (unlockpt(master) < 0) {
4136 r = log_error_errno(errno, "Failed to unlock tty: %m");
4137 goto finish;
4138 }
4139
4140 if (!arg_quiet)
4141 log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.",
4142 arg_machine, arg_image ?: arg_directory);
4143
4144 assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1) >= 0);
4145
4146 if (prctl(PR_SET_CHILD_SUBREAPER, 1) < 0) {
4147 r = log_error_errno(errno, "Failed to become subreaper: %m");
4148 goto finish;
4149 }
4150
4151 for (;;) {
4152 r = run(master,
4153 console,
4154 dissected_image,
4155 interactive, secondary,
4156 fds,
4157 veth_name, &veth_created,
4158 &exposed,
4159 &pid, &ret);
4160 if (r <= 0)
4161 break;
4162 }
4163
4164 finish:
4165 sd_notify(false,
4166 r == 0 && ret == EXIT_FORCE_RESTART ? "STOPPING=1\nSTATUS=Restarting..." :
4167 "STOPPING=1\nSTATUS=Terminating...");
4168
4169 if (pid > 0)
4170 (void) kill(pid, SIGKILL);
4171
4172 /* Try to flush whatever is still queued in the pty */
4173 if (master >= 0) {
4174 (void) copy_bytes(master, STDOUT_FILENO, (uint64_t) -1, 0);
4175 master = safe_close(master);
4176 }
4177
4178 if (pid > 0)
4179 (void) wait_for_terminate(pid, NULL);
4180
4181 if (remove_directory && arg_directory) {
4182 int k;
4183
4184 k = rm_rf(arg_directory, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
4185 if (k < 0)
4186 log_warning_errno(k, "Cannot remove '%s', ignoring: %m", arg_directory);
4187 }
4188
4189 if (remove_image && arg_image) {
4190 if (unlink(arg_image) < 0)
4191 log_warning_errno(errno, "Can't remove image file '%s', ignoring: %m", arg_image);
4192 }
4193
4194 if (remove_tmprootdir) {
4195 if (rmdir(tmprootdir) < 0)
4196 log_debug_errno(errno, "Can't remove temporary root directory '%s', ignoring: %m", tmprootdir);
4197 }
4198
4199 if (arg_machine) {
4200 const char *p;
4201
4202 p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
4203 (void) rm_rf(p, REMOVE_ROOT);
4204 }
4205
4206 expose_port_flush(arg_expose_ports, &exposed);
4207
4208 if (veth_created)
4209 (void) remove_veth_links(veth_name, arg_network_veth_extra);
4210 (void) remove_bridge(arg_network_zone);
4211
4212 free(arg_directory);
4213 free(arg_template);
4214 free(arg_image);
4215 free(arg_machine);
4216 free(arg_user);
4217 free(arg_pivot_root_new);
4218 free(arg_pivot_root_old);
4219 free(arg_chdir);
4220 strv_free(arg_setenv);
4221 free(arg_network_bridge);
4222 strv_free(arg_network_interfaces);
4223 strv_free(arg_network_macvlan);
4224 strv_free(arg_network_ipvlan);
4225 strv_free(arg_network_veth_extra);
4226 strv_free(arg_parameters);
4227 custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts);
4228 expose_port_free_all(arg_expose_ports);
4229 free(arg_root_hash);
4230
4231 return r < 0 ? EXIT_FAILURE : ret;
4232 }
Unnamed repository; edit this file 'description' to name the repository.