1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
8 #include <linux/loop.h>
10 #include <selinux/selinux.h>
14 #include <sys/ioctl.h>
15 #include <sys/personality.h>
16 #include <sys/prctl.h>
17 #include <sys/types.h>
23 #include "sd-daemon.h"
26 #include "alloc-util.h"
27 #include "ether-addr-util.h"
29 #include "base-filesystem.h"
30 #include "blkid-util.h"
31 #include "btrfs-util.h"
33 #include "bus-error.h"
34 #include "bus-locator.h"
37 #include "capability-util.h"
38 #include "cgroup-util.h"
40 #include "common-signal.h"
42 #include "cpu-set-util.h"
43 #include "creds-util.h"
44 #include "dev-setup.h"
45 #include "discover-image.h"
46 #include "dissect-image.h"
52 #include "format-util.h"
55 #include "hexdecoct.h"
56 #include "hostname-setup.h"
57 #include "hostname-util.h"
58 #include "id128-util.h"
61 #include "loop-util.h"
62 #include "loopback-setup.h"
63 #include "machine-credential.h"
65 #include "main-func.h"
66 #include "missing_sched.h"
68 #include "mount-util.h"
69 #include "mountpoint-util.h"
70 #include "namespace-util.h"
71 #include "netlink-util.h"
72 #include "nspawn-bind-user.h"
73 #include "nspawn-cgroup.h"
74 #include "nspawn-def.h"
75 #include "nspawn-expose-ports.h"
76 #include "nspawn-mount.h"
77 #include "nspawn-network.h"
78 #include "nspawn-oci.h"
79 #include "nspawn-patch-uid.h"
80 #include "nspawn-register.h"
81 #include "nspawn-seccomp.h"
82 #include "nspawn-settings.h"
83 #include "nspawn-setuid.h"
84 #include "nspawn-stub-pid1.h"
85 #include "nspawn-util.h"
87 #include "nulstr-util.h"
90 #include "parse-argument.h"
91 #include "parse-util.h"
92 #include "pretty-print.h"
93 #include "process-util.h"
95 #include "random-util.h"
96 #include "raw-clone.h"
97 #include "resolve-util.h"
98 #include "rlimit-util.h"
100 #include "seccomp-util.h"
101 #include "selinux-util.h"
102 #include "signal-util.h"
103 #include "socket-util.h"
104 #include "stat-util.h"
105 #include "stdio-util.h"
106 #include "string-table.h"
107 #include "string-util.h"
109 #include "sysctl-util.h"
110 #include "terminal-util.h"
111 #include "tmpfile-util.h"
112 #include "umask-util.h"
113 #include "unit-name.h"
114 #include "user-util.h"
116 /* The notify socket inside the container it can use to talk to nspawn using the sd_notify(3) protocol */
117 #define NSPAWN_NOTIFY_SOCKET_PATH "/run/host/notify"
118 #define NSPAWN_MOUNT_TUNNEL "/run/host/incoming"
120 #define EXIT_FORCE_RESTART 133
122 typedef enum ContainerStatus
{
123 CONTAINER_TERMINATED
,
127 static char *arg_directory
= NULL
;
128 static char *arg_template
= NULL
;
129 static char *arg_chdir
= NULL
;
130 static char *arg_pivot_root_new
= NULL
;
131 static char *arg_pivot_root_old
= NULL
;
132 static char *arg_user
= NULL
;
133 static uid_t arg_uid
= UID_INVALID
;
134 static gid_t arg_gid
= GID_INVALID
;
135 static gid_t
* arg_supplementary_gids
= NULL
;
136 static size_t arg_n_supplementary_gids
= 0;
137 static sd_id128_t arg_uuid
= {};
138 static char *arg_machine
= NULL
; /* The name used by the host to refer to this */
139 static char *arg_hostname
= NULL
; /* The name the payload sees by default */
140 static const char *arg_selinux_context
= NULL
;
141 static const char *arg_selinux_apifs_context
= NULL
;
142 static char *arg_slice
= NULL
;
143 static bool arg_private_network
= false;
144 static bool arg_read_only
= false;
145 static StartMode arg_start_mode
= START_PID1
;
146 static bool arg_ephemeral
= false;
147 static LinkJournal arg_link_journal
= LINK_AUTO
;
148 static bool arg_link_journal_try
= false;
149 static uint64_t arg_caps_retain
=
150 (1ULL << CAP_AUDIT_CONTROL
) |
151 (1ULL << CAP_AUDIT_WRITE
) |
152 (1ULL << CAP_CHOWN
) |
153 (1ULL << CAP_DAC_OVERRIDE
) |
154 (1ULL << CAP_DAC_READ_SEARCH
) |
155 (1ULL << CAP_FOWNER
) |
156 (1ULL << CAP_FSETID
) |
157 (1ULL << CAP_IPC_OWNER
) |
159 (1ULL << CAP_LEASE
) |
160 (1ULL << CAP_LINUX_IMMUTABLE
) |
161 (1ULL << CAP_MKNOD
) |
162 (1ULL << CAP_NET_BIND_SERVICE
) |
163 (1ULL << CAP_NET_BROADCAST
) |
164 (1ULL << CAP_NET_RAW
) |
165 (1ULL << CAP_SETFCAP
) |
166 (1ULL << CAP_SETGID
) |
167 (1ULL << CAP_SETPCAP
) |
168 (1ULL << CAP_SETUID
) |
169 (1ULL << CAP_SYS_ADMIN
) |
170 (1ULL << CAP_SYS_BOOT
) |
171 (1ULL << CAP_SYS_CHROOT
) |
172 (1ULL << CAP_SYS_NICE
) |
173 (1ULL << CAP_SYS_PTRACE
) |
174 (1ULL << CAP_SYS_RESOURCE
) |
175 (1ULL << CAP_SYS_TTY_CONFIG
);
176 static uint64_t arg_caps_ambient
= 0;
177 static CapabilityQuintet arg_full_capabilities
= CAPABILITY_QUINTET_NULL
;
178 static CustomMount
*arg_custom_mounts
= NULL
;
179 static size_t arg_n_custom_mounts
= 0;
180 static char **arg_setenv
= NULL
;
181 static bool arg_quiet
= false;
182 static bool arg_register
= true;
183 static bool arg_keep_unit
= false;
184 static char **arg_network_interfaces
= NULL
;
185 static char **arg_network_macvlan
= NULL
;
186 static char **arg_network_ipvlan
= NULL
;
187 static bool arg_network_veth
= false;
188 static char **arg_network_veth_extra
= NULL
;
189 static char *arg_network_bridge
= NULL
;
190 static char *arg_network_zone
= NULL
;
191 static char *arg_network_namespace_path
= NULL
;
192 struct ether_addr arg_network_provided_mac
= {};
193 static PagerFlags arg_pager_flags
= 0;
194 static unsigned long arg_personality
= PERSONALITY_INVALID
;
195 static char *arg_image
= NULL
;
196 static char *arg_oci_bundle
= NULL
;
197 static VolatileMode arg_volatile_mode
= VOLATILE_NO
;
198 static ExposePort
*arg_expose_ports
= NULL
;
199 static char **arg_property
= NULL
;
200 static sd_bus_message
*arg_property_message
= NULL
;
201 static UserNamespaceMode arg_userns_mode
= USER_NAMESPACE_NO
;
202 static uid_t arg_uid_shift
= UID_INVALID
, arg_uid_range
= 0x10000U
;
203 static UserNamespaceOwnership arg_userns_ownership
= _USER_NAMESPACE_OWNERSHIP_INVALID
;
204 static int arg_kill_signal
= 0;
205 static CGroupUnified arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_UNKNOWN
;
206 static SettingsMask arg_settings_mask
= 0;
207 static int arg_settings_trusted
= -1;
208 static char **arg_parameters
= NULL
;
209 static const char *arg_container_service_name
= "systemd-nspawn";
210 static bool arg_notify_ready
= false;
211 static bool arg_use_cgns
= true;
212 static unsigned long arg_clone_ns_flags
= CLONE_NEWIPC
|CLONE_NEWPID
|CLONE_NEWUTS
;
213 static MountSettingsMask arg_mount_settings
= MOUNT_APPLY_APIVFS_RO
|MOUNT_APPLY_TMPFS_TMP
;
214 static VeritySettings arg_verity_settings
= VERITY_SETTINGS_DEFAULT
;
215 static char **arg_syscall_allow_list
= NULL
;
216 static char **arg_syscall_deny_list
= NULL
;
218 static scmp_filter_ctx arg_seccomp
= NULL
;
220 static struct rlimit
*arg_rlimit
[_RLIMIT_MAX
] = {};
221 static bool arg_no_new_privileges
= false;
222 static int arg_oom_score_adjust
= 0;
223 static bool arg_oom_score_adjust_set
= false;
224 static CPUSet arg_cpu_set
= {};
225 static ResolvConfMode arg_resolv_conf
= RESOLV_CONF_AUTO
;
226 static TimezoneMode arg_timezone
= TIMEZONE_AUTO
;
227 static unsigned arg_console_width
= UINT_MAX
, arg_console_height
= UINT_MAX
;
228 static DeviceNode
* arg_extra_nodes
= NULL
;
229 static size_t arg_n_extra_nodes
= 0;
230 static char **arg_sysctl
= NULL
;
231 static ConsoleMode arg_console_mode
= _CONSOLE_MODE_INVALID
;
232 static MachineCredential
*arg_credentials
= NULL
;
233 static size_t arg_n_credentials
= 0;
234 static char **arg_bind_user
= NULL
;
235 static bool arg_suppress_sync
= false;
236 static char *arg_settings_filename
= NULL
;
237 static Architecture arg_architecture
= _ARCHITECTURE_INVALID
;
238 static ImagePolicy
*arg_image_policy
= NULL
;
240 STATIC_DESTRUCTOR_REGISTER(arg_directory
, freep
);
241 STATIC_DESTRUCTOR_REGISTER(arg_template
, freep
);
242 STATIC_DESTRUCTOR_REGISTER(arg_chdir
, freep
);
243 STATIC_DESTRUCTOR_REGISTER(arg_pivot_root_new
, freep
);
244 STATIC_DESTRUCTOR_REGISTER(arg_pivot_root_old
, freep
);
245 STATIC_DESTRUCTOR_REGISTER(arg_user
, freep
);
246 STATIC_DESTRUCTOR_REGISTER(arg_supplementary_gids
, freep
);
247 STATIC_DESTRUCTOR_REGISTER(arg_machine
, freep
);
248 STATIC_DESTRUCTOR_REGISTER(arg_hostname
, freep
);
249 STATIC_DESTRUCTOR_REGISTER(arg_slice
, freep
);
250 STATIC_DESTRUCTOR_REGISTER(arg_setenv
, strv_freep
);
251 STATIC_DESTRUCTOR_REGISTER(arg_network_interfaces
, strv_freep
);
252 STATIC_DESTRUCTOR_REGISTER(arg_network_macvlan
, strv_freep
);
253 STATIC_DESTRUCTOR_REGISTER(arg_network_ipvlan
, strv_freep
);
254 STATIC_DESTRUCTOR_REGISTER(arg_network_veth_extra
, strv_freep
);
255 STATIC_DESTRUCTOR_REGISTER(arg_network_bridge
, freep
);
256 STATIC_DESTRUCTOR_REGISTER(arg_network_zone
, freep
);
257 STATIC_DESTRUCTOR_REGISTER(arg_network_namespace_path
, freep
);
258 STATIC_DESTRUCTOR_REGISTER(arg_image
, freep
);
259 STATIC_DESTRUCTOR_REGISTER(arg_oci_bundle
, freep
);
260 STATIC_DESTRUCTOR_REGISTER(arg_property
, strv_freep
);
261 STATIC_DESTRUCTOR_REGISTER(arg_property_message
, sd_bus_message_unrefp
);
262 STATIC_DESTRUCTOR_REGISTER(arg_parameters
, strv_freep
);
263 STATIC_DESTRUCTOR_REGISTER(arg_verity_settings
, verity_settings_done
);
264 STATIC_DESTRUCTOR_REGISTER(arg_syscall_allow_list
, strv_freep
);
265 STATIC_DESTRUCTOR_REGISTER(arg_syscall_deny_list
, strv_freep
);
267 STATIC_DESTRUCTOR_REGISTER(arg_seccomp
, seccomp_releasep
);
269 STATIC_DESTRUCTOR_REGISTER(arg_cpu_set
, cpu_set_reset
);
270 STATIC_DESTRUCTOR_REGISTER(arg_sysctl
, strv_freep
);
271 STATIC_DESTRUCTOR_REGISTER(arg_bind_user
, strv_freep
);
272 STATIC_DESTRUCTOR_REGISTER(arg_settings_filename
, freep
);
273 STATIC_DESTRUCTOR_REGISTER(arg_image_policy
, image_policy_freep
);
275 static int handle_arg_console(const char *arg
) {
276 if (streq(arg
, "help")) {
285 if (streq(arg
, "interactive"))
286 arg_console_mode
= CONSOLE_INTERACTIVE
;
287 else if (streq(arg
, "read-only"))
288 arg_console_mode
= CONSOLE_READ_ONLY
;
289 else if (streq(arg
, "passive"))
290 arg_console_mode
= CONSOLE_PASSIVE
;
291 else if (streq(arg
, "pipe")) {
292 if (isatty(STDIN_FILENO
) > 0 && isatty(STDOUT_FILENO
) > 0)
293 log_full(arg_quiet
? LOG_DEBUG
: LOG_NOTICE
,
294 "Console mode 'pipe' selected, but standard input/output are connected to an interactive TTY. "
295 "Most likely you want to use 'interactive' console mode for proper interactivity and shell job control. "
296 "Proceeding anyway.");
298 arg_console_mode
= CONSOLE_PIPE
;
299 } else if (streq(arg
, "autopipe")) {
300 if (isatty(STDIN_FILENO
) > 0 && isatty(STDOUT_FILENO
) > 0)
301 arg_console_mode
= CONSOLE_INTERACTIVE
;
303 arg_console_mode
= CONSOLE_PIPE
;
305 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Unknown console mode: %s", optarg
);
307 arg_settings_mask
|= SETTING_CONSOLE_MODE
;
311 static int help(void) {
312 _cleanup_free_
char *link
= NULL
;
315 pager_open(arg_pager_flags
);
317 r
= terminal_urlify_man("systemd-nspawn", "1", &link
);
321 printf("%1$s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
322 "%5$sSpawn a command or OS in a light-weight container.%6$s\n\n"
323 " -h --help Show this help\n"
324 " --version Print version string\n"
325 " -q --quiet Do not show status information\n"
326 " --no-pager Do not pipe output into a pager\n"
327 " --settings=BOOLEAN Load additional settings from .nspawn file\n\n"
329 " -D --directory=PATH Root directory for the container\n"
330 " --template=PATH Initialize root directory from template directory,\n"
332 " -x --ephemeral Run container with snapshot of root directory, and\n"
333 " remove it after exit\n"
334 " -i --image=PATH Root file system disk image (or device node) for\n"
336 " --image-policy=POLICY Specify disk image dissection policy\n"
337 " --oci-bundle=PATH OCI bundle directory\n"
338 " --read-only Mount the root directory read-only\n"
339 " --volatile[=MODE] Run the system in volatile mode\n"
340 " --root-hash=HASH Specify verity root hash for root disk image\n"
341 " --root-hash-sig=SIG Specify pkcs7 signature of root hash for verity\n"
342 " as a DER encoded PKCS7, either as a path to a file\n"
343 " or as an ASCII base64 encoded string prefixed by\n"
345 " --verity-data=PATH Specify hash device for verity\n"
346 " --pivot-root=PATH[:PATH]\n"
347 " Pivot root to given directory in the container\n\n"
348 "%3$sExecution:%4$s\n"
349 " -a --as-pid2 Maintain a stub init as PID1, invoke binary as PID2\n"
350 " -b --boot Boot up full system (i.e. invoke init)\n"
351 " --chdir=PATH Set working directory in the container\n"
352 " -E --setenv=NAME[=VALUE] Pass an environment variable to PID 1\n"
353 " -u --user=USER Run the command under specified user or UID\n"
354 " --kill-signal=SIGNAL Select signal to use for shutting down PID 1\n"
355 " --notify-ready=BOOLEAN Receive notifications from the child init process\n"
356 " --suppress-sync=BOOLEAN\n"
357 " Suppress any form of disk data synchronization\n\n"
358 "%3$sSystem Identity:%4$s\n"
359 " -M --machine=NAME Set the machine name for the container\n"
360 " --hostname=NAME Override the hostname for the container\n"
361 " --uuid=UUID Set a specific machine UUID for the container\n\n"
362 "%3$sProperties:%4$s\n"
363 " -S --slice=SLICE Place the container in the specified slice\n"
364 " --property=NAME=VALUE Set scope unit property\n"
365 " --register=BOOLEAN Register container as machine\n"
366 " --keep-unit Do not register a scope for the machine, reuse\n"
367 " the service unit nspawn is running in\n\n"
368 "%3$sUser Namespacing:%4$s\n"
369 " --private-users=no Run without user namespacing\n"
370 " --private-users=yes|pick|identity\n"
371 " Run within user namespace, autoselect UID/GID range\n"
372 " --private-users=UIDBASE[:NUIDS]\n"
373 " Similar, but with user configured UID/GID range\n"
374 " --private-users-ownership=MODE\n"
375 " Adjust ('chown') or map ('map') OS tree ownership\n"
376 " to private UID/GID range\n"
377 " -U Equivalent to --private-users=pick and\n"
378 " --private-users-ownership=auto\n\n"
379 "%3$sNetworking:%4$s\n"
380 " --private-network Disable network in container\n"
381 " --network-interface=HOSTIF[:CONTAINERIF]\n"
382 " Assign an existing network interface to the\n"
384 " --network-macvlan=HOSTIF[:CONTAINERIF]\n"
385 " Create a macvlan network interface based on an\n"
386 " existing network interface to the container\n"
387 " --network-ipvlan=HOSTIF[:CONTAINERIF]\n"
388 " Create an ipvlan network interface based on an\n"
389 " existing network interface to the container\n"
390 " -n --network-veth Add a virtual Ethernet connection between host\n"
392 " --network-veth-extra=HOSTIF[:CONTAINERIF]\n"
393 " Add an additional virtual Ethernet link between\n"
394 " host and container\n"
395 " --network-bridge=INTERFACE\n"
396 " Add a virtual Ethernet connection to the container\n"
397 " and attach it to an existing bridge on the host\n"
398 " --network-zone=NAME Similar, but attach the new interface to an\n"
399 " an automatically managed bridge interface\n"
400 " --network-namespace-path=PATH\n"
401 " Set network namespace to the one represented by\n"
402 " the specified kernel namespace file node\n"
403 " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n"
404 " Expose a container IP port on the host\n\n"
405 "%3$sSecurity:%4$s\n"
406 " --capability=CAP In addition to the default, retain specified\n"
408 " --drop-capability=CAP Drop the specified capability from the default set\n"
409 " --ambient-capability=CAP\n"
410 " Sets the specified capability for the started\n"
411 " process. Not useful if booting a machine.\n"
412 " --no-new-privileges Set PR_SET_NO_NEW_PRIVS flag for container payload\n"
413 " --system-call-filter=LIST|~LIST\n"
414 " Permit/prohibit specific system calls\n"
415 " -Z --selinux-context=SECLABEL\n"
416 " Set the SELinux security context to be used by\n"
417 " processes in the container\n"
418 " -L --selinux-apifs-context=SECLABEL\n"
419 " Set the SELinux security context to be used by\n"
420 " API/tmpfs file systems in the container\n\n"
421 "%3$sResources:%4$s\n"
422 " --rlimit=NAME=LIMIT Set a resource limit for the payload\n"
423 " --oom-score-adjust=VALUE\n"
424 " Adjust the OOM score value for the payload\n"
425 " --cpu-affinity=CPUS Adjust the CPU affinity of the container\n"
426 " --personality=ARCH Pick personality for this container\n\n"
427 "%3$sIntegration:%4$s\n"
428 " --resolv-conf=MODE Select mode of /etc/resolv.conf initialization\n"
429 " --timezone=MODE Select mode of /etc/localtime initialization\n"
430 " --link-journal=MODE Link up guest journal, one of no, auto, guest, \n"
431 " host, try-guest, try-host\n"
432 " -j Equivalent to --link-journal=try-guest\n\n"
434 " --bind=PATH[:PATH[:OPTIONS]]\n"
435 " Bind mount a file or directory from the host into\n"
437 " --bind-ro=PATH[:PATH[:OPTIONS]\n"
438 " Similar, but creates a read-only bind mount\n"
439 " --inaccessible=PATH Over-mount file node with inaccessible node to mask\n"
441 " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n"
442 " --overlay=PATH[:PATH...]:PATH\n"
443 " Create an overlay mount from the host to \n"
445 " --overlay-ro=PATH[:PATH...]:PATH\n"
446 " Similar, but creates a read-only overlay mount\n"
447 " --bind-user=NAME Bind user from host to container\n\n"
448 "%3$sInput/Output:%4$s\n"
449 " --console=MODE Select how stdin/stdout/stderr and /dev/console are\n"
450 " set up for the container.\n"
451 " -P --pipe Equivalent to --console=pipe\n\n"
452 "%3$sCredentials:%4$s\n"
453 " --set-credential=ID:VALUE\n"
454 " Pass a credential with literal value to container.\n"
455 " --load-credential=ID:PATH\n"
456 " Load credential to pass to container from file or\n"
457 " AF_UNIX stream socket.\n"
458 "\nSee the %2$s for details.\n",
459 program_invocation_short_name
,
469 static int custom_mount_check_all(void) {
472 for (i
= 0; i
< arg_n_custom_mounts
; i
++) {
473 CustomMount
*m
= &arg_custom_mounts
[i
];
475 if (path_equal(m
->destination
, "/") && arg_userns_mode
!= USER_NAMESPACE_NO
) {
476 if (arg_userns_ownership
!= USER_NAMESPACE_OWNERSHIP_OFF
)
477 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
478 "--private-users-ownership=own may not be combined with custom root mounts.");
479 if (arg_uid_shift
== UID_INVALID
)
480 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
481 "--private-users with automatic UID shift may not be combined with custom root mounts.");
488 static int detect_unified_cgroup_hierarchy_from_environment(void) {
489 const char *e
, *var
= "SYSTEMD_NSPAWN_UNIFIED_HIERARCHY";
492 /* Allow the user to control whether the unified hierarchy is used */
496 /* $UNIFIED_CGROUP_HIERARCHY has been renamed to $SYSTEMD_NSPAWN_UNIFIED_HIERARCHY. */
497 var
= "UNIFIED_CGROUP_HIERARCHY";
502 r
= parse_boolean(e
);
504 return log_error_errno(r
, "Failed to parse $%s: %m", var
);
506 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_ALL
;
508 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_NONE
;
514 static int detect_unified_cgroup_hierarchy_from_image(const char *directory
) {
517 /* Let's inherit the mode to use from the host system, but let's take into consideration what systemd
518 * in the image actually supports. */
519 r
= cg_all_unified();
521 return log_error_errno(r
, "Failed to determine whether we are in all unified mode.");
523 /* Unified cgroup hierarchy support was added in 230. Unfortunately the detection
524 * routine only detects 231, so we'll have a false negative here for 230. */
525 r
= systemd_installation_has_version(directory
, "230");
527 return log_error_errno(r
, "Failed to determine systemd version in container: %m");
529 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_ALL
;
531 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_NONE
;
532 } else if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER
) > 0) {
533 /* Mixed cgroup hierarchy support was added in 233 */
534 r
= systemd_installation_has_version(directory
, "233");
536 return log_error_errno(r
, "Failed to determine systemd version in container: %m");
538 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_SYSTEMD
;
540 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_NONE
;
542 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_NONE
;
544 log_debug("Using %s hierarchy for container.",
545 arg_unified_cgroup_hierarchy
== CGROUP_UNIFIED_NONE
? "legacy" :
546 arg_unified_cgroup_hierarchy
== CGROUP_UNIFIED_SYSTEMD
? "hybrid" : "unified");
551 static int parse_capability_spec(const char *spec
, uint64_t *ret_mask
) {
556 _cleanup_free_
char *t
= NULL
;
558 r
= extract_first_word(&spec
, &t
, ",", 0);
560 return log_error_errno(r
, "Failed to parse capability %s.", t
);
564 if (streq(t
, "help")) {
565 for (int i
= 0; i
< capability_list_length(); i
++) {
568 name
= capability_to_name(i
);
579 r
= capability_from_name(t
);
581 return log_error_errno(r
, "Failed to parse capability %s.", t
);
588 return 1; /* continue */
591 static int parse_share_ns_env(const char *name
, unsigned long ns_flag
) {
594 r
= getenv_bool(name
);
598 return log_error_errno(r
, "Failed to parse $%s: %m", name
);
600 arg_clone_ns_flags
= (arg_clone_ns_flags
& ~ns_flag
) | (r
> 0 ? 0 : ns_flag
);
601 arg_settings_mask
|= SETTING_CLONE_NS_FLAGS
;
605 static int parse_mount_settings_env(void) {
609 r
= getenv_bool("SYSTEMD_NSPAWN_TMPFS_TMP");
610 if (r
< 0 && r
!= -ENXIO
)
611 return log_error_errno(r
, "Failed to parse $SYSTEMD_NSPAWN_TMPFS_TMP: %m");
613 SET_FLAG(arg_mount_settings
, MOUNT_APPLY_TMPFS_TMP
, r
> 0);
615 e
= getenv("SYSTEMD_NSPAWN_API_VFS_WRITABLE");
616 if (streq_ptr(e
, "network"))
617 arg_mount_settings
|= MOUNT_APPLY_APIVFS_RO
|MOUNT_APPLY_APIVFS_NETNS
;
620 r
= parse_boolean(e
);
622 return log_error_errno(r
, "Failed to parse $SYSTEMD_NSPAWN_API_VFS_WRITABLE: %m");
624 SET_FLAG(arg_mount_settings
, MOUNT_APPLY_APIVFS_RO
, r
== 0);
625 SET_FLAG(arg_mount_settings
, MOUNT_APPLY_APIVFS_NETNS
, false);
631 static int parse_environment(void) {
635 r
= parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_IPC", CLONE_NEWIPC
);
638 r
= parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_PID", CLONE_NEWPID
);
641 r
= parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_UTS", CLONE_NEWUTS
);
644 r
= parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_SYSTEM", CLONE_NEWIPC
|CLONE_NEWPID
|CLONE_NEWUTS
);
648 r
= parse_mount_settings_env();
652 /* SYSTEMD_NSPAWN_USE_CGNS=0 can be used to disable CLONE_NEWCGROUP use,
653 * even if it is supported. If not supported, it has no effect. */
654 if (!cg_ns_supported())
655 arg_use_cgns
= false;
657 r
= getenv_bool("SYSTEMD_NSPAWN_USE_CGNS");
660 return log_error_errno(r
, "Failed to parse $SYSTEMD_NSPAWN_USE_CGNS: %m");
664 arg_use_cgns
= r
> 0;
665 arg_settings_mask
|= SETTING_USE_CGNS
;
669 e
= getenv("SYSTEMD_NSPAWN_CONTAINER_SERVICE");
671 arg_container_service_name
= e
;
673 e
= getenv("SYSTEMD_NSPAWN_NETWORK_MAC");
675 r
= parse_ether_addr(e
, &arg_network_provided_mac
);
677 return log_error_errno(r
, "Failed to parse provided MAC address via environment variable");
680 r
= getenv_bool("SYSTEMD_SUPPRESS_SYNC");
682 arg_suppress_sync
= r
;
683 else if (r
!= -ENXIO
)
684 log_debug_errno(r
, "Failed to parse $SYSTEMD_SUPPRESS_SYNC, ignoring: %m");
686 return detect_unified_cgroup_hierarchy_from_environment();
689 static int parse_argv(int argc
, char *argv
[]) {
696 ARG_AMBIENT_CAPABILITY
,
708 ARG_NETWORK_INTERFACE
,
713 ARG_NETWORK_VETH_EXTRA
,
714 ARG_NETWORK_NAMESPACE_PATH
,
724 ARG_PRIVATE_USERS_CHOWN
,
725 ARG_PRIVATE_USERS_OWNERSHIP
,
730 ARG_SYSTEM_CALL_FILTER
,
733 ARG_NO_NEW_PRIVILEGES
,
734 ARG_OOM_SCORE_ADJUST
,
749 static const struct option options
[] = {
750 { "help", no_argument
, NULL
, 'h' },
751 { "version", no_argument
, NULL
, ARG_VERSION
},
752 { "directory", required_argument
, NULL
, 'D' },
753 { "template", required_argument
, NULL
, ARG_TEMPLATE
},
754 { "ephemeral", no_argument
, NULL
, 'x' },
755 { "user", required_argument
, NULL
, 'u' },
756 { "private-network", no_argument
, NULL
, ARG_PRIVATE_NETWORK
},
757 { "as-pid2", no_argument
, NULL
, 'a' },
758 { "boot", no_argument
, NULL
, 'b' },
759 { "uuid", required_argument
, NULL
, ARG_UUID
},
760 { "read-only", no_argument
, NULL
, ARG_READ_ONLY
},
761 { "capability", required_argument
, NULL
, ARG_CAPABILITY
},
762 { "ambient-capability", required_argument
, NULL
, ARG_AMBIENT_CAPABILITY
},
763 { "drop-capability", required_argument
, NULL
, ARG_DROP_CAPABILITY
},
764 { "no-new-privileges", required_argument
, NULL
, ARG_NO_NEW_PRIVILEGES
},
765 { "link-journal", required_argument
, NULL
, ARG_LINK_JOURNAL
},
766 { "bind", required_argument
, NULL
, ARG_BIND
},
767 { "bind-ro", required_argument
, NULL
, ARG_BIND_RO
},
768 { "tmpfs", required_argument
, NULL
, ARG_TMPFS
},
769 { "overlay", required_argument
, NULL
, ARG_OVERLAY
},
770 { "overlay-ro", required_argument
, NULL
, ARG_OVERLAY_RO
},
771 { "inaccessible", required_argument
, NULL
, ARG_INACCESSIBLE
},
772 { "machine", required_argument
, NULL
, 'M' },
773 { "hostname", required_argument
, NULL
, ARG_HOSTNAME
},
774 { "slice", required_argument
, NULL
, 'S' },
775 { "setenv", required_argument
, NULL
, 'E' },
776 { "selinux-context", required_argument
, NULL
, 'Z' },
777 { "selinux-apifs-context", required_argument
, NULL
, 'L' },
778 { "quiet", no_argument
, NULL
, 'q' },
779 { "share-system", no_argument
, NULL
, ARG_SHARE_SYSTEM
}, /* not documented */
780 { "register", required_argument
, NULL
, ARG_REGISTER
},
781 { "keep-unit", no_argument
, NULL
, ARG_KEEP_UNIT
},
782 { "network-interface", required_argument
, NULL
, ARG_NETWORK_INTERFACE
},
783 { "network-macvlan", required_argument
, NULL
, ARG_NETWORK_MACVLAN
},
784 { "network-ipvlan", required_argument
, NULL
, ARG_NETWORK_IPVLAN
},
785 { "network-veth", no_argument
, NULL
, 'n' },
786 { "network-veth-extra", required_argument
, NULL
, ARG_NETWORK_VETH_EXTRA
},
787 { "network-bridge", required_argument
, NULL
, ARG_NETWORK_BRIDGE
},
788 { "network-zone", required_argument
, NULL
, ARG_NETWORK_ZONE
},
789 { "network-namespace-path", required_argument
, NULL
, ARG_NETWORK_NAMESPACE_PATH
},
790 { "personality", required_argument
, NULL
, ARG_PERSONALITY
},
791 { "image", required_argument
, NULL
, 'i' },
792 { "volatile", optional_argument
, NULL
, ARG_VOLATILE
},
793 { "port", required_argument
, NULL
, 'p' },
794 { "property", required_argument
, NULL
, ARG_PROPERTY
},
795 { "private-users", optional_argument
, NULL
, ARG_PRIVATE_USERS
},
796 { "private-users-chown", optional_argument
, NULL
, ARG_PRIVATE_USERS_CHOWN
}, /* obsolete */
797 { "private-users-ownership",required_argument
, NULL
, ARG_PRIVATE_USERS_OWNERSHIP
},
798 { "kill-signal", required_argument
, NULL
, ARG_KILL_SIGNAL
},
799 { "settings", required_argument
, NULL
, ARG_SETTINGS
},
800 { "chdir", required_argument
, NULL
, ARG_CHDIR
},
801 { "pivot-root", required_argument
, NULL
, ARG_PIVOT_ROOT
},
802 { "notify-ready", required_argument
, NULL
, ARG_NOTIFY_READY
},
803 { "root-hash", required_argument
, NULL
, ARG_ROOT_HASH
},
804 { "root-hash-sig", required_argument
, NULL
, ARG_ROOT_HASH_SIG
},
805 { "verity-data", required_argument
, NULL
, ARG_VERITY_DATA
},
806 { "system-call-filter", required_argument
, NULL
, ARG_SYSTEM_CALL_FILTER
},
807 { "rlimit", required_argument
, NULL
, ARG_RLIMIT
},
808 { "oom-score-adjust", required_argument
, NULL
, ARG_OOM_SCORE_ADJUST
},
809 { "cpu-affinity", required_argument
, NULL
, ARG_CPU_AFFINITY
},
810 { "resolv-conf", required_argument
, NULL
, ARG_RESOLV_CONF
},
811 { "timezone", required_argument
, NULL
, ARG_TIMEZONE
},
812 { "console", required_argument
, NULL
, ARG_CONSOLE
},
813 { "pipe", no_argument
, NULL
, ARG_PIPE
},
814 { "oci-bundle", required_argument
, NULL
, ARG_OCI_BUNDLE
},
815 { "no-pager", no_argument
, NULL
, ARG_NO_PAGER
},
816 { "set-credential", required_argument
, NULL
, ARG_SET_CREDENTIAL
},
817 { "load-credential", required_argument
, NULL
, ARG_LOAD_CREDENTIAL
},
818 { "bind-user", required_argument
, NULL
, ARG_BIND_USER
},
819 { "suppress-sync", required_argument
, NULL
, ARG_SUPPRESS_SYNC
},
820 { "image-policy", required_argument
, NULL
, ARG_IMAGE_POLICY
},
825 uint64_t plus
= 0, minus
= 0;
826 bool mask_all_settings
= false, mask_no_settings
= false;
831 /* Resetting to 0 forces the invocation of an internal initialization routine of getopt_long()
832 * that checks for GNU extensions in optstring ('-' or '+' at the beginning). */
834 while ((c
= getopt_long(argc
, argv
, "+hD:u:abL:M:jS:Z:qi:xp:nUE:P", options
, NULL
)) >= 0)
844 r
= parse_path_argument(optarg
, false, &arg_directory
);
848 arg_settings_mask
|= SETTING_DIRECTORY
;
852 r
= parse_path_argument(optarg
, false, &arg_template
);
856 arg_settings_mask
|= SETTING_DIRECTORY
;
860 r
= parse_path_argument(optarg
, false, &arg_image
);
864 arg_settings_mask
|= SETTING_DIRECTORY
;
868 r
= parse_path_argument(optarg
, false, &arg_oci_bundle
);
875 arg_ephemeral
= true;
876 arg_settings_mask
|= SETTING_EPHEMERAL
;
880 r
= free_and_strdup(&arg_user
, optarg
);
884 arg_settings_mask
|= SETTING_USER
;
887 case ARG_NETWORK_ZONE
: {
888 _cleanup_free_
char *j
= NULL
;
890 j
= strjoin("vz-", optarg
);
894 if (!ifname_valid(j
))
895 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
896 "Network zone name not valid: %s", j
);
898 free_and_replace(arg_network_zone
, j
);
900 arg_network_veth
= true;
901 arg_private_network
= true;
902 arg_settings_mask
|= SETTING_NETWORK
;
906 case ARG_NETWORK_BRIDGE
:
908 if (!ifname_valid(optarg
))
909 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
910 "Bridge interface name not valid: %s", optarg
);
912 r
= free_and_strdup(&arg_network_bridge
, optarg
);
918 arg_network_veth
= true;
919 arg_private_network
= true;
920 arg_settings_mask
|= SETTING_NETWORK
;
923 case ARG_NETWORK_VETH_EXTRA
:
924 r
= veth_extra_parse(&arg_network_veth_extra
, optarg
);
926 return log_error_errno(r
, "Failed to parse --network-veth-extra= parameter: %s", optarg
);
928 arg_private_network
= true;
929 arg_settings_mask
|= SETTING_NETWORK
;
932 case ARG_NETWORK_INTERFACE
:
933 r
= interface_pair_parse(&arg_network_interfaces
, optarg
);
937 arg_private_network
= true;
938 arg_settings_mask
|= SETTING_NETWORK
;
941 case ARG_NETWORK_MACVLAN
:
942 r
= macvlan_pair_parse(&arg_network_macvlan
, optarg
);
946 arg_private_network
= true;
947 arg_settings_mask
|= SETTING_NETWORK
;
950 case ARG_NETWORK_IPVLAN
:
951 r
= ipvlan_pair_parse(&arg_network_ipvlan
, optarg
);
956 case ARG_PRIVATE_NETWORK
:
957 arg_private_network
= true;
958 arg_settings_mask
|= SETTING_NETWORK
;
961 case ARG_NETWORK_NAMESPACE_PATH
:
962 r
= parse_path_argument(optarg
, false, &arg_network_namespace_path
);
966 arg_settings_mask
|= SETTING_NETWORK
;
970 if (arg_start_mode
== START_PID2
)
971 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
972 "--boot and --as-pid2 may not be combined.");
974 arg_start_mode
= START_BOOT
;
975 arg_settings_mask
|= SETTING_START_MODE
;
979 if (arg_start_mode
== START_BOOT
)
980 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
981 "--boot and --as-pid2 may not be combined.");
983 arg_start_mode
= START_PID2
;
984 arg_settings_mask
|= SETTING_START_MODE
;
988 r
= id128_from_string_nonzero(optarg
, &arg_uuid
);
990 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
991 "Machine UUID may not be all zeroes.");
993 return log_error_errno(r
, "Invalid UUID: %s", optarg
);
995 arg_settings_mask
|= SETTING_MACHINE_ID
;
999 _cleanup_free_
char *mangled
= NULL
;
1001 r
= unit_name_mangle_with_suffix(optarg
, NULL
, UNIT_NAME_MANGLE_WARN
, ".slice", &mangled
);
1005 free_and_replace(arg_slice
, mangled
);
1006 arg_settings_mask
|= SETTING_SLICE
;
1011 if (isempty(optarg
))
1012 arg_machine
= mfree(arg_machine
);
1014 if (!hostname_is_valid(optarg
, 0))
1015 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1016 "Invalid machine name: %s", optarg
);
1018 r
= free_and_strdup(&arg_machine
, optarg
);
1025 if (isempty(optarg
))
1026 arg_hostname
= mfree(arg_hostname
);
1028 if (!hostname_is_valid(optarg
, 0))
1029 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1030 "Invalid hostname: %s", optarg
);
1032 r
= free_and_strdup(&arg_hostname
, optarg
);
1037 arg_settings_mask
|= SETTING_HOSTNAME
;
1041 arg_selinux_context
= optarg
;
1045 arg_selinux_apifs_context
= optarg
;
1049 arg_read_only
= true;
1050 arg_settings_mask
|= SETTING_READ_ONLY
;
1053 case ARG_AMBIENT_CAPABILITY
: {
1055 r
= parse_capability_spec(optarg
, &m
);
1058 arg_caps_ambient
|= m
;
1059 arg_settings_mask
|= SETTING_CAPABILITY
;
1062 case ARG_CAPABILITY
:
1063 case ARG_DROP_CAPABILITY
: {
1065 r
= parse_capability_spec(optarg
, &m
);
1069 if (c
== ARG_CAPABILITY
)
1073 arg_settings_mask
|= SETTING_CAPABILITY
;
1076 case ARG_NO_NEW_PRIVILEGES
:
1077 r
= parse_boolean(optarg
);
1079 return log_error_errno(r
, "Failed to parse --no-new-privileges= argument: %s", optarg
);
1081 arg_no_new_privileges
= r
;
1082 arg_settings_mask
|= SETTING_NO_NEW_PRIVILEGES
;
1086 arg_link_journal
= LINK_GUEST
;
1087 arg_link_journal_try
= true;
1088 arg_settings_mask
|= SETTING_LINK_JOURNAL
;
1091 case ARG_LINK_JOURNAL
:
1092 r
= parse_link_journal(optarg
, &arg_link_journal
, &arg_link_journal_try
);
1094 return log_error_errno(r
, "Failed to parse link journal mode %s", optarg
);
1096 arg_settings_mask
|= SETTING_LINK_JOURNAL
;
1101 r
= bind_mount_parse(&arg_custom_mounts
, &arg_n_custom_mounts
, optarg
, c
== ARG_BIND_RO
);
1103 return log_error_errno(r
, "Failed to parse --bind(-ro)= argument %s: %m", optarg
);
1105 arg_settings_mask
|= SETTING_CUSTOM_MOUNTS
;
1109 r
= tmpfs_mount_parse(&arg_custom_mounts
, &arg_n_custom_mounts
, optarg
);
1111 return log_error_errno(r
, "Failed to parse --tmpfs= argument %s: %m", optarg
);
1113 arg_settings_mask
|= SETTING_CUSTOM_MOUNTS
;
1117 case ARG_OVERLAY_RO
:
1118 r
= overlay_mount_parse(&arg_custom_mounts
, &arg_n_custom_mounts
, optarg
, c
== ARG_OVERLAY_RO
);
1119 if (r
== -EADDRNOTAVAIL
)
1120 return log_error_errno(r
, "--overlay(-ro)= needs at least two colon-separated directories specified.");
1122 return log_error_errno(r
, "Failed to parse --overlay(-ro)= argument %s: %m", optarg
);
1124 arg_settings_mask
|= SETTING_CUSTOM_MOUNTS
;
1127 case ARG_INACCESSIBLE
:
1128 r
= inaccessible_mount_parse(&arg_custom_mounts
, &arg_n_custom_mounts
, optarg
);
1130 return log_error_errno(r
, "Failed to parse --inaccessible= argument %s: %m", optarg
);
1132 arg_settings_mask
|= SETTING_CUSTOM_MOUNTS
;
1136 r
= strv_env_replace_strdup_passthrough(&arg_setenv
, optarg
);
1138 return log_error_errno(r
, "Cannot assign environment variable %s: %m", optarg
);
1140 arg_settings_mask
|= SETTING_ENVIRONMENT
;
1147 case ARG_SHARE_SYSTEM
:
1148 /* We don't officially support this anymore, except for compat reasons. People should use the
1149 * $SYSTEMD_NSPAWN_SHARE_* environment variables instead. */
1150 log_warning("Please do not use --share-system anymore, use $SYSTEMD_NSPAWN_SHARE_* instead.");
1151 arg_clone_ns_flags
= 0;
1155 r
= parse_boolean(optarg
);
1157 log_error("Failed to parse --register= argument: %s", optarg
);
1165 arg_keep_unit
= true;
1168 case ARG_PERSONALITY
:
1170 arg_personality
= personality_from_string(optarg
);
1171 if (arg_personality
== PERSONALITY_INVALID
)
1172 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1173 "Unknown or unsupported personality '%s'.", optarg
);
1175 arg_settings_mask
|= SETTING_PERSONALITY
;
1181 arg_volatile_mode
= VOLATILE_YES
;
1182 else if (streq(optarg
, "help")) {
1183 DUMP_STRING_TABLE(volatile_mode
, VolatileMode
, _VOLATILE_MODE_MAX
);
1188 m
= volatile_mode_from_string(optarg
);
1190 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1191 "Failed to parse --volatile= argument: %s", optarg
);
1193 arg_volatile_mode
= m
;
1196 arg_settings_mask
|= SETTING_VOLATILE_MODE
;
1200 r
= expose_port_parse(&arg_expose_ports
, optarg
);
1202 return log_error_errno(r
, "Duplicate port specification: %s", optarg
);
1204 return log_error_errno(r
, "Failed to parse host port %s: %m", optarg
);
1206 arg_settings_mask
|= SETTING_EXPOSE_PORTS
;
1210 if (strv_extend(&arg_property
, optarg
) < 0)
1215 case ARG_PRIVATE_USERS
: {
1220 else if (!in_charset(optarg
, DIGITS
))
1221 /* do *not* parse numbers as booleans */
1222 boolean
= parse_boolean(optarg
);
1227 /* no: User namespacing off */
1228 arg_userns_mode
= USER_NAMESPACE_NO
;
1229 arg_uid_shift
= UID_INVALID
;
1230 arg_uid_range
= UINT32_C(0x10000);
1231 } else if (boolean
> 0) {
1232 /* yes: User namespacing on, UID range is read from root dir */
1233 arg_userns_mode
= USER_NAMESPACE_FIXED
;
1234 arg_uid_shift
= UID_INVALID
;
1235 arg_uid_range
= UINT32_C(0x10000);
1236 } else if (streq(optarg
, "pick")) {
1237 /* pick: User namespacing on, UID range is picked randomly */
1238 arg_userns_mode
= USER_NAMESPACE_PICK
; /* Note that arg_userns_ownership is
1239 * implied by USER_NAMESPACE_PICK
1241 arg_uid_shift
= UID_INVALID
;
1242 arg_uid_range
= UINT32_C(0x10000);
1244 } else if (streq(optarg
, "identity")) {
1245 /* identity: User namespaces on, UID range is map the 0…0xFFFF range to
1246 * itself, i.e. we don't actually map anything, but do take benefit of
1247 * isolation of capability sets. */
1248 arg_userns_mode
= USER_NAMESPACE_FIXED
;
1250 arg_uid_range
= UINT32_C(0x10000);
1252 _cleanup_free_
char *buffer
= NULL
;
1253 const char *range
, *shift
;
1255 /* anything else: User namespacing on, UID range is explicitly configured */
1257 range
= strchr(optarg
, ':');
1259 buffer
= strndup(optarg
, range
- optarg
);
1265 r
= safe_atou32(range
, &arg_uid_range
);
1267 return log_error_errno(r
, "Failed to parse UID range \"%s\": %m", range
);
1271 r
= parse_uid(shift
, &arg_uid_shift
);
1273 return log_error_errno(r
, "Failed to parse UID \"%s\": %m", optarg
);
1275 arg_userns_mode
= USER_NAMESPACE_FIXED
;
1277 if (!userns_shift_range_valid(arg_uid_shift
, arg_uid_range
))
1278 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "UID range cannot be empty or go beyond " UID_FMT
".", UID_INVALID
);
1281 arg_settings_mask
|= SETTING_USERNS
;
1286 if (userns_supported()) {
1287 arg_userns_mode
= USER_NAMESPACE_PICK
; /* Note that arg_userns_ownership is
1288 * implied by USER_NAMESPACE_PICK
1290 arg_uid_shift
= UID_INVALID
;
1291 arg_uid_range
= UINT32_C(0x10000);
1293 arg_settings_mask
|= SETTING_USERNS
;
1298 case ARG_PRIVATE_USERS_CHOWN
:
1299 arg_userns_ownership
= USER_NAMESPACE_OWNERSHIP_CHOWN
;
1301 arg_settings_mask
|= SETTING_USERNS
;
1304 case ARG_PRIVATE_USERS_OWNERSHIP
:
1305 if (streq(optarg
, "help")) {
1306 DUMP_STRING_TABLE(user_namespace_ownership
, UserNamespaceOwnership
, _USER_NAMESPACE_OWNERSHIP_MAX
);
1310 arg_userns_ownership
= user_namespace_ownership_from_string(optarg
);
1311 if (arg_userns_ownership
< 0)
1312 return log_error_errno(arg_userns_ownership
, "Cannot parse --user-namespace-ownership= value: %s", optarg
);
1314 arg_settings_mask
|= SETTING_USERNS
;
1317 case ARG_KILL_SIGNAL
:
1318 if (streq(optarg
, "help")) {
1319 DUMP_STRING_TABLE(signal
, int, _NSIG
);
1323 arg_kill_signal
= signal_from_string(optarg
);
1324 if (arg_kill_signal
< 0)
1325 return log_error_errno(arg_kill_signal
, "Cannot parse signal: %s", optarg
);
1327 arg_settings_mask
|= SETTING_KILL_SIGNAL
;
1332 /* no → do not read files
1333 * yes → read files, do not override cmdline, trust only subset
1334 * override → read files, override cmdline, trust only subset
1335 * trusted → read files, do not override cmdline, trust all
1338 r
= parse_boolean(optarg
);
1340 if (streq(optarg
, "trusted")) {
1341 mask_all_settings
= false;
1342 mask_no_settings
= false;
1343 arg_settings_trusted
= true;
1345 } else if (streq(optarg
, "override")) {
1346 mask_all_settings
= false;
1347 mask_no_settings
= true;
1348 arg_settings_trusted
= -1;
1350 return log_error_errno(r
, "Failed to parse --settings= argument: %s", optarg
);
1353 mask_all_settings
= false;
1354 mask_no_settings
= false;
1355 arg_settings_trusted
= -1;
1358 mask_all_settings
= true;
1359 mask_no_settings
= false;
1360 arg_settings_trusted
= false;
1366 if (!path_is_absolute(optarg
))
1367 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1368 "Working directory %s is not an absolute path.", optarg
);
1370 r
= free_and_strdup(&arg_chdir
, optarg
);
1374 arg_settings_mask
|= SETTING_WORKING_DIRECTORY
;
1377 case ARG_PIVOT_ROOT
:
1378 r
= pivot_root_parse(&arg_pivot_root_new
, &arg_pivot_root_old
, optarg
);
1380 return log_error_errno(r
, "Failed to parse --pivot-root= argument %s: %m", optarg
);
1382 arg_settings_mask
|= SETTING_PIVOT_ROOT
;
1385 case ARG_NOTIFY_READY
:
1386 r
= parse_boolean(optarg
);
1388 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1389 "%s is not a valid notify mode. Valid modes are: yes, no, and ready.", optarg
);
1390 arg_notify_ready
= r
;
1391 arg_settings_mask
|= SETTING_NOTIFY_READY
;
1394 case ARG_ROOT_HASH
: {
1395 _cleanup_free_
void *k
= NULL
;
1398 r
= unhexmem(optarg
, strlen(optarg
), &k
, &l
);
1400 return log_error_errno(r
, "Failed to parse root hash: %s", optarg
);
1401 if (l
< sizeof(sd_id128_t
))
1402 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Root hash must be at least 128-bit long: %s", optarg
);
1404 free_and_replace(arg_verity_settings
.root_hash
, k
);
1405 arg_verity_settings
.root_hash_size
= l
;
1409 case ARG_ROOT_HASH_SIG
: {
1414 if ((value
= startswith(optarg
, "base64:"))) {
1415 r
= unbase64mem(value
, strlen(value
), &p
, &l
);
1417 return log_error_errno(r
, "Failed to parse root hash signature '%s': %m", optarg
);
1420 r
= read_full_file(optarg
, (char**) &p
, &l
);
1422 return log_error_errno(r
, "Failed parse root hash signature file '%s': %m", optarg
);
1425 free_and_replace(arg_verity_settings
.root_hash_sig
, p
);
1426 arg_verity_settings
.root_hash_sig_size
= l
;
1430 case ARG_VERITY_DATA
:
1431 r
= parse_path_argument(optarg
, false, &arg_verity_settings
.data_path
);
1436 case ARG_SYSTEM_CALL_FILTER
: {
1440 negative
= optarg
[0] == '~';
1441 items
= negative
? optarg
+ 1 : optarg
;
1444 _cleanup_free_
char *word
= NULL
;
1446 r
= extract_first_word(&items
, &word
, NULL
, 0);
1452 return log_error_errno(r
, "Failed to parse system call filter: %m");
1455 r
= strv_extend(&arg_syscall_deny_list
, word
);
1457 r
= strv_extend(&arg_syscall_allow_list
, word
);
1462 arg_settings_mask
|= SETTING_SYSCALL_FILTER
;
1468 _cleanup_free_
char *name
= NULL
;
1471 if (streq(optarg
, "help")) {
1472 DUMP_STRING_TABLE(rlimit
, int, _RLIMIT_MAX
);
1476 eq
= strchr(optarg
, '=');
1478 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1479 "--rlimit= expects an '=' assignment.");
1481 name
= strndup(optarg
, eq
- optarg
);
1485 rl
= rlimit_from_string_harder(name
);
1487 return log_error_errno(rl
, "Unknown resource limit: %s", name
);
1489 if (!arg_rlimit
[rl
]) {
1490 arg_rlimit
[rl
] = new0(struct rlimit
, 1);
1491 if (!arg_rlimit
[rl
])
1495 r
= rlimit_parse(rl
, eq
+ 1, arg_rlimit
[rl
]);
1497 return log_error_errno(r
, "Failed to parse resource limit: %s", eq
+ 1);
1499 arg_settings_mask
|= SETTING_RLIMIT_FIRST
<< rl
;
1503 case ARG_OOM_SCORE_ADJUST
:
1504 r
= parse_oom_score_adjust(optarg
, &arg_oom_score_adjust
);
1506 return log_error_errno(r
, "Failed to parse --oom-score-adjust= parameter: %s", optarg
);
1508 arg_oom_score_adjust_set
= true;
1509 arg_settings_mask
|= SETTING_OOM_SCORE_ADJUST
;
1512 case ARG_CPU_AFFINITY
: {
1515 r
= parse_cpu_set(optarg
, &cpuset
);
1517 return log_error_errno(r
, "Failed to parse CPU affinity mask %s: %m", optarg
);
1519 cpu_set_reset(&arg_cpu_set
);
1520 arg_cpu_set
= cpuset
;
1521 arg_settings_mask
|= SETTING_CPU_AFFINITY
;
1525 case ARG_RESOLV_CONF
:
1526 if (streq(optarg
, "help")) {
1527 DUMP_STRING_TABLE(resolv_conf_mode
, ResolvConfMode
, _RESOLV_CONF_MODE_MAX
);
1531 arg_resolv_conf
= resolv_conf_mode_from_string(optarg
);
1532 if (arg_resolv_conf
< 0)
1533 return log_error_errno(arg_resolv_conf
,
1534 "Failed to parse /etc/resolv.conf mode: %s", optarg
);
1536 arg_settings_mask
|= SETTING_RESOLV_CONF
;
1540 if (streq(optarg
, "help")) {
1541 DUMP_STRING_TABLE(timezone_mode
, TimezoneMode
, _TIMEZONE_MODE_MAX
);
1545 arg_timezone
= timezone_mode_from_string(optarg
);
1546 if (arg_timezone
< 0)
1547 return log_error_errno(arg_timezone
,
1548 "Failed to parse /etc/localtime mode: %s", optarg
);
1550 arg_settings_mask
|= SETTING_TIMEZONE
;
1554 r
= handle_arg_console(optarg
);
1561 r
= handle_arg_console("pipe");
1567 arg_pager_flags
|= PAGER_DISABLE
;
1570 case ARG_SET_CREDENTIAL
:
1571 r
= machine_credential_set(&arg_credentials
, &arg_n_credentials
, optarg
);
1575 arg_settings_mask
|= SETTING_CREDENTIALS
;
1578 case ARG_LOAD_CREDENTIAL
:
1579 r
= machine_credential_load(&arg_credentials
, &arg_n_credentials
, optarg
);
1583 arg_settings_mask
|= SETTING_CREDENTIALS
;
1587 if (!valid_user_group_name(optarg
, 0))
1588 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Invalid user name to bind: %s", optarg
);
1590 if (strv_extend(&arg_bind_user
, optarg
) < 0)
1593 arg_settings_mask
|= SETTING_BIND_USER
;
1596 case ARG_SUPPRESS_SYNC
:
1597 r
= parse_boolean_argument("--suppress-sync=", optarg
, &arg_suppress_sync
);
1601 arg_settings_mask
|= SETTING_SUPPRESS_SYNC
;
1604 case ARG_IMAGE_POLICY
:
1605 r
= parse_image_policy_argument(optarg
, &arg_image_policy
);
1614 assert_not_reached();
1617 if (argc
> optind
) {
1618 strv_free(arg_parameters
);
1619 arg_parameters
= strv_copy(argv
+ optind
);
1620 if (!arg_parameters
)
1623 arg_settings_mask
|= SETTING_START_MODE
;
1626 if (arg_ephemeral
&& arg_template
&& !arg_directory
)
1627 /* User asked for ephemeral execution but specified --template= instead of --directory=. Semantically
1628 * such an invocation makes some sense, see https://github.com/systemd/systemd/issues/3667. Let's
1629 * accept this here, and silently make "--ephemeral --template=" equivalent to "--ephemeral
1631 arg_directory
= TAKE_PTR(arg_template
);
1633 arg_caps_retain
|= plus
;
1634 arg_caps_retain
|= arg_private_network
? UINT64_C(1) << CAP_NET_ADMIN
: 0;
1636 /* If we're not unsharing the network namespace and are unsharing the user namespace, we won't have
1637 * permissions to bind ports in the container, so let's drop the CAP_NET_BIND_SERVICE capability to
1639 if (!arg_private_network
&& arg_userns_mode
!= USER_NAMESPACE_NO
&& arg_uid_shift
> 0)
1640 arg_caps_retain
&= ~(UINT64_C(1) << CAP_NET_BIND_SERVICE
);
1642 arg_caps_retain
&= ~minus
;
1644 /* Make sure to parse environment before we reset the settings mask below */
1645 r
= parse_environment();
1649 /* Load all settings from .nspawn files */
1650 if (mask_no_settings
)
1651 arg_settings_mask
= 0;
1653 /* Don't load any settings from .nspawn files */
1654 if (mask_all_settings
)
1655 arg_settings_mask
= _SETTINGS_MASK_ALL
;
1660 static int verify_arguments(void) {
1663 if (arg_start_mode
== START_PID2
&& arg_unified_cgroup_hierarchy
== CGROUP_UNIFIED_UNKNOWN
) {
1664 /* If we are running the stub init in the container, we don't need to look at what the init
1665 * in the container supports, because we are not using it. Let's immediately pick the right
1666 * setting based on the host system configuration.
1668 * We only do this, if the user didn't use an environment variable to override the detection.
1671 r
= cg_all_unified();
1673 return log_error_errno(r
, "Failed to determine whether we are in all unified mode.");
1675 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_ALL
;
1676 else if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER
) > 0)
1677 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_SYSTEMD
;
1679 arg_unified_cgroup_hierarchy
= CGROUP_UNIFIED_NONE
;
1682 if (arg_userns_mode
!= USER_NAMESPACE_NO
)
1683 arg_mount_settings
|= MOUNT_USE_USERNS
;
1685 if (arg_private_network
)
1686 arg_mount_settings
|= MOUNT_APPLY_APIVFS_NETNS
;
1688 if (!(arg_clone_ns_flags
& CLONE_NEWPID
) ||
1689 !(arg_clone_ns_flags
& CLONE_NEWUTS
)) {
1690 arg_register
= false;
1691 if (arg_start_mode
!= START_PID1
)
1692 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--boot cannot be used without namespacing.");
1695 if (arg_userns_ownership
< 0)
1696 arg_userns_ownership
=
1697 arg_userns_mode
== USER_NAMESPACE_PICK
? USER_NAMESPACE_OWNERSHIP_AUTO
:
1698 USER_NAMESPACE_OWNERSHIP_OFF
;
1700 if (arg_start_mode
== START_BOOT
&& arg_kill_signal
<= 0)
1701 arg_kill_signal
= SIGRTMIN
+3;
1703 if (arg_volatile_mode
!= VOLATILE_NO
) /* Make sure all file systems contained in the image are mounted read-only if we are in volatile mode */
1704 arg_read_only
= true;
1706 if (has_custom_root_mount(arg_custom_mounts
, arg_n_custom_mounts
))
1707 arg_read_only
= true;
1709 if (arg_keep_unit
&& arg_register
&& cg_pid_get_owner_uid(0, NULL
) >= 0)
1710 /* Save the user from accidentally registering either user-$SESSION.scope or user@.service.
1711 * The latter is not technically a user session, but we don't need to labour the point. */
1712 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--keep-unit --register=yes may not be used when invoked from a user session.");
1714 if (arg_directory
&& arg_image
)
1715 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--directory= and --image= may not be combined.");
1717 if (arg_template
&& arg_image
)
1718 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--template= and --image= may not be combined.");
1720 if (arg_template
&& !(arg_directory
|| arg_machine
))
1721 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--template= needs --directory= or --machine=.");
1723 if (arg_ephemeral
&& arg_template
)
1724 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--ephemeral and --template= may not be combined.");
1726 if (arg_ephemeral
&& !IN_SET(arg_link_journal
, LINK_NO
, LINK_AUTO
))
1727 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--ephemeral and --link-journal= may not be combined.");
1729 if (arg_userns_mode
!= USER_NAMESPACE_NO
&& !userns_supported())
1730 return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP
), "--private-users= is not supported, kernel compiled without user namespace support.");
1732 if (arg_userns_ownership
== USER_NAMESPACE_OWNERSHIP_CHOWN
&& arg_read_only
)
1733 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1734 "--read-only and --private-users-ownership=chown may not be combined.");
1736 /* We don't support --private-users-ownership=chown together with any of the volatile modes since we
1737 * couldn't change the read-only part of the tree (i.e. /usr) anyway, or because it would trigger a
1738 * massive copy-up (in case of overlay) making the entire exercise pointless. */
1739 if (arg_userns_ownership
== USER_NAMESPACE_OWNERSHIP_CHOWN
&& arg_volatile_mode
!= VOLATILE_NO
)
1740 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--volatile= and --private-users-ownership=chown may not be combined.");
1742 /* If --network-namespace-path is given with any other network-related option (except --private-network),
1743 * we need to error out, to avoid conflicts between different network options. */
1744 if (arg_network_namespace_path
&&
1745 (arg_network_interfaces
|| arg_network_macvlan
||
1746 arg_network_ipvlan
|| arg_network_veth_extra
||
1747 arg_network_bridge
|| arg_network_zone
||
1749 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--network-namespace-path= cannot be combined with other network options.");
1751 if (arg_network_bridge
&& arg_network_zone
)
1752 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
1753 "--network-bridge= and --network-zone= may not be combined.");
1755 if (arg_userns_mode
!= USER_NAMESPACE_NO
&& (arg_mount_settings
& MOUNT_APPLY_APIVFS_NETNS
) && !arg_private_network
)
1756 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Invalid namespacing settings. Mounting sysfs with --private-users requires --private-network.");
1758 if (arg_userns_mode
!= USER_NAMESPACE_NO
&& !(arg_mount_settings
& MOUNT_APPLY_APIVFS_RO
))
1759 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Cannot combine --private-users with read-write mounts.");
1761 if (arg_expose_ports
&& !arg_private_network
)
1762 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Cannot use --port= without private networking.");
1764 if (arg_caps_ambient
) {
1765 if (arg_caps_ambient
== UINT64_MAX
)
1766 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "AmbientCapability= does not support the value all.");
1768 if ((arg_caps_ambient
& arg_caps_retain
) != arg_caps_ambient
)
1769 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "AmbientCapability= setting is not fully covered by Capability= setting.");
1771 if (arg_start_mode
== START_BOOT
)
1772 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "AmbientCapability= setting is not useful for boot mode.");
1775 if (arg_userns_mode
== USER_NAMESPACE_NO
&& !strv_isempty(arg_bind_user
))
1776 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "--bind-user= requires --private-users");
1778 /* Drop duplicate --bind-user= entries */
1779 strv_uniq(arg_bind_user
);
1781 r
= custom_mount_check_all();
1788 static int verify_network_interfaces_initialized(void) {
1790 r
= test_network_interfaces_initialized(arg_network_interfaces
);
1794 r
= test_network_interfaces_initialized(arg_network_macvlan
);
1798 r
= test_network_interfaces_initialized(arg_network_ipvlan
);
1805 int userns_lchown(const char *p
, uid_t uid
, gid_t gid
) {
1808 if (arg_userns_mode
== USER_NAMESPACE_NO
)
1811 if (uid
== UID_INVALID
&& gid
== GID_INVALID
)
1814 if (uid
!= UID_INVALID
) {
1815 uid
+= arg_uid_shift
;
1817 if (uid
< arg_uid_shift
|| uid
>= arg_uid_shift
+ arg_uid_range
)
1821 if (gid
!= GID_INVALID
) {
1822 gid
+= (gid_t
) arg_uid_shift
;
1824 if (gid
< (gid_t
) arg_uid_shift
|| gid
>= (gid_t
) (arg_uid_shift
+ arg_uid_range
))
1828 return RET_NERRNO(lchown(p
, uid
, gid
));
1831 int userns_mkdir(const char *root
, const char *path
, mode_t mode
, uid_t uid
, gid_t gid
) {
1835 q
= prefix_roota(root
, path
);
1836 r
= RET_NERRNO(mkdir(q
, mode
));
1842 return userns_lchown(q
, uid
, gid
);
1845 static const char *timezone_from_path(const char *path
) {
1846 return PATH_STARTSWITH_SET(
1848 "../usr/share/zoneinfo/",
1849 "/usr/share/zoneinfo/");
1852 static bool etc_writable(void) {
1853 return !arg_read_only
|| IN_SET(arg_volatile_mode
, VOLATILE_YES
, VOLATILE_OVERLAY
);
1856 static int setup_timezone(const char *dest
) {
1857 _cleanup_free_
char *p
= NULL
, *etc
= NULL
;
1858 const char *where
, *check
;
1864 if (IN_SET(arg_timezone
, TIMEZONE_AUTO
, TIMEZONE_SYMLINK
)) {
1865 r
= readlink_malloc("/etc/localtime", &p
);
1866 if (r
== -ENOENT
&& arg_timezone
== TIMEZONE_AUTO
)
1867 m
= etc_writable() ? TIMEZONE_DELETE
: TIMEZONE_OFF
;
1868 else if (r
== -EINVAL
&& arg_timezone
== TIMEZONE_AUTO
) /* regular file? */
1869 m
= etc_writable() ? TIMEZONE_COPY
: TIMEZONE_BIND
;
1871 log_warning_errno(r
, "Failed to read host's /etc/localtime symlink, not updating container timezone: %m");
1872 /* To handle warning, delete /etc/localtime and replace it with a symbolic link to a time zone data
1876 * ln -s /usr/share/zoneinfo/UTC /etc/localtime
1879 } else if (arg_timezone
== TIMEZONE_AUTO
)
1880 m
= etc_writable() ? TIMEZONE_SYMLINK
: TIMEZONE_BIND
;
1886 if (m
== TIMEZONE_OFF
)
1889 r
= chase("/etc", dest
, CHASE_PREFIX_ROOT
, &etc
, NULL
);
1891 log_warning_errno(r
, "Failed to resolve /etc path in container, ignoring: %m");
1895 where
= strjoina(etc
, "/localtime");
1899 case TIMEZONE_DELETE
:
1900 if (unlink(where
) < 0)
1901 log_full_errno(errno
== ENOENT
? LOG_DEBUG
: LOG_WARNING
, errno
, "Failed to remove '%s', ignoring: %m", where
);
1905 case TIMEZONE_SYMLINK
: {
1906 _cleanup_free_
char *q
= NULL
;
1907 const char *z
, *what
;
1909 z
= timezone_from_path(p
);
1911 log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone.");
1915 r
= readlink_malloc(where
, &q
);
1916 if (r
>= 0 && streq_ptr(timezone_from_path(q
), z
))
1917 return 0; /* Already pointing to the right place? Then do nothing .. */
1919 check
= strjoina(dest
, "/usr/share/zoneinfo/", z
);
1920 r
= chase(check
, dest
, 0, NULL
, NULL
);
1922 log_debug_errno(r
, "Timezone %s does not exist (or is not accessible) in container, not creating symlink: %m", z
);
1924 if (unlink(where
) < 0 && errno
!= ENOENT
) {
1925 log_full_errno(IN_SET(errno
, EROFS
, EACCES
, EPERM
) ? LOG_DEBUG
: LOG_WARNING
, /* Don't complain on read-only images */
1926 errno
, "Failed to remove existing timezone info %s in container, ignoring: %m", where
);
1930 what
= strjoina("../usr/share/zoneinfo/", z
);
1931 if (symlink(what
, where
) < 0) {
1932 log_full_errno(IN_SET(errno
, EROFS
, EACCES
, EPERM
) ? LOG_DEBUG
: LOG_WARNING
,
1933 errno
, "Failed to correct timezone of container, ignoring: %m");
1943 case TIMEZONE_BIND
: {
1944 _cleanup_free_
char *resolved
= NULL
;
1947 found
= chase(where
, dest
, CHASE_NONEXISTENT
, &resolved
, NULL
);
1949 log_warning_errno(found
, "Failed to resolve /etc/localtime path in container, ignoring: %m");
1953 if (found
== 0) /* missing? */
1954 (void) touch(resolved
);
1956 r
= mount_nofollow_verbose(LOG_WARNING
, "/etc/localtime", resolved
, NULL
, MS_BIND
, NULL
);
1958 return mount_nofollow_verbose(LOG_ERR
, NULL
, resolved
, NULL
, MS_BIND
|MS_REMOUNT
|MS_RDONLY
|MS_NOSUID
|MS_NODEV
, NULL
);
1964 /* If mounting failed, try to copy */
1965 r
= copy_file_atomic("/etc/localtime", where
, 0644, COPY_REFLINK
|COPY_REPLACE
);
1967 log_full_errno(IN_SET(r
, -EROFS
, -EACCES
, -EPERM
) ? LOG_DEBUG
: LOG_WARNING
, r
,
1968 "Failed to copy /etc/localtime to %s, ignoring: %m", where
);
1975 assert_not_reached();
1978 /* Fix permissions of the symlink or file copy we just created */
1979 r
= userns_lchown(where
, 0, 0);
1981 log_warning_errno(r
, "Failed to chown /etc/localtime, ignoring: %m");
1986 static int have_resolv_conf(const char *path
) {
1989 if (access(path
, F_OK
) < 0) {
1990 if (errno
== ENOENT
)
1993 return log_debug_errno(errno
, "Failed to determine whether '%s' is available: %m", path
);
1999 static int resolved_listening(void) {
2000 _cleanup_(sd_bus_error_free
) sd_bus_error error
= SD_BUS_ERROR_NULL
;
2001 _cleanup_(sd_bus_flush_close_unrefp
) sd_bus
*bus
= NULL
;
2002 _cleanup_free_
char *dns_stub_listener_mode
= NULL
;
2005 /* Check if resolved is listening */
2007 r
= sd_bus_open_system(&bus
);
2009 return log_debug_errno(r
, "Failed to open system bus: %m");
2011 r
= bus_name_has_owner(bus
, "org.freedesktop.resolve1", NULL
);
2013 return log_debug_errno(r
, "Failed to check whether the 'org.freedesktop.resolve1' bus name is taken: %m");
2017 r
= bus_get_property_string(bus
, bus_resolve_mgr
, "DNSStubListener", &error
, &dns_stub_listener_mode
);
2019 return log_debug_errno(r
, "Failed to query DNSStubListener property: %s", bus_error_message(&error
, r
));
2021 return STR_IN_SET(dns_stub_listener_mode
, "udp", "yes");
2024 static int setup_resolv_conf(const char *dest
) {
2025 _cleanup_free_
char *etc
= NULL
;
2026 const char *where
, *what
;
2032 if (arg_resolv_conf
== RESOLV_CONF_AUTO
) {
2033 if (arg_private_network
)
2034 m
= RESOLV_CONF_OFF
;
2035 else if (have_resolv_conf(PRIVATE_STUB_RESOLV_CONF
) > 0 && resolved_listening() > 0)
2036 m
= etc_writable() ? RESOLV_CONF_COPY_STUB
: RESOLV_CONF_BIND_STUB
;
2037 else if (have_resolv_conf("/etc/resolv.conf") > 0)
2038 m
= etc_writable() ? RESOLV_CONF_COPY_HOST
: RESOLV_CONF_BIND_HOST
;
2040 m
= etc_writable() ? RESOLV_CONF_DELETE
: RESOLV_CONF_OFF
;
2043 m
= arg_resolv_conf
;
2045 if (m
== RESOLV_CONF_OFF
)
2048 r
= chase("/etc", dest
, CHASE_PREFIX_ROOT
, &etc
, NULL
);
2050 log_warning_errno(r
, "Failed to resolve /etc path in container, ignoring: %m");
2054 where
= strjoina(etc
, "/resolv.conf");
2056 if (m
== RESOLV_CONF_DELETE
) {
2057 if (unlink(where
) < 0)
2058 log_full_errno(errno
== ENOENT
? LOG_DEBUG
: LOG_WARNING
, errno
, "Failed to remove '%s', ignoring: %m", where
);
2063 if (IN_SET(m
, RESOLV_CONF_BIND_STATIC
, RESOLV_CONF_REPLACE_STATIC
, RESOLV_CONF_COPY_STATIC
))
2064 what
= PRIVATE_STATIC_RESOLV_CONF
;
2065 else if (IN_SET(m
, RESOLV_CONF_BIND_UPLINK
, RESOLV_CONF_REPLACE_UPLINK
, RESOLV_CONF_COPY_UPLINK
))
2066 what
= PRIVATE_UPLINK_RESOLV_CONF
;
2067 else if (IN_SET(m
, RESOLV_CONF_BIND_STUB
, RESOLV_CONF_REPLACE_STUB
, RESOLV_CONF_COPY_STUB
))
2068 what
= PRIVATE_STUB_RESOLV_CONF
;
2070 what
= "/etc/resolv.conf";
2072 if (IN_SET(m
, RESOLV_CONF_BIND_HOST
, RESOLV_CONF_BIND_STATIC
, RESOLV_CONF_BIND_UPLINK
, RESOLV_CONF_BIND_STUB
)) {
2073 _cleanup_free_
char *resolved
= NULL
;
2076 found
= chase(where
, dest
, CHASE_NONEXISTENT
|CHASE_NOFOLLOW
, &resolved
, NULL
);
2078 log_warning_errno(found
, "Failed to resolve /etc/resolv.conf path in container, ignoring: %m");
2082 if (found
== 0) /* missing? */
2083 (void) touch(resolved
);
2085 r
= mount_nofollow_verbose(LOG_WARNING
, what
, resolved
, NULL
, MS_BIND
, NULL
);
2087 return mount_nofollow_verbose(LOG_ERR
, NULL
, resolved
, NULL
, MS_BIND
|MS_REMOUNT
|MS_RDONLY
|MS_NOSUID
|MS_NODEV
, NULL
);
2089 /* If that didn't work, let's copy the file */
2092 if (IN_SET(m
, RESOLV_CONF_REPLACE_HOST
, RESOLV_CONF_REPLACE_STATIC
, RESOLV_CONF_REPLACE_UPLINK
, RESOLV_CONF_REPLACE_STUB
))
2093 r
= copy_file_atomic(what
, where
, 0644, COPY_REFLINK
|COPY_REPLACE
);
2095 r
= copy_file(what
, where
, O_TRUNC
|O_NOFOLLOW
, 0644, COPY_REFLINK
);
2097 /* If the file already exists as symlink, let's suppress the warning, under the assumption that
2098 * resolved or something similar runs inside and the symlink points there.
2100 * If the disk image is read-only, there's also no point in complaining.
2102 log_full_errno(!IN_SET(RESOLV_CONF_COPY_HOST
, RESOLV_CONF_COPY_STATIC
, RESOLV_CONF_COPY_UPLINK
, RESOLV_CONF_COPY_STUB
) &&
2103 IN_SET(r
, -ELOOP
, -EROFS
, -EACCES
, -EPERM
) ? LOG_DEBUG
: LOG_WARNING
, r
,
2104 "Failed to copy /etc/resolv.conf to %s, ignoring: %m", where
);
2108 r
= userns_lchown(where
, 0, 0);
2110 log_warning_errno(r
, "Failed to chown /etc/resolv.conf, ignoring: %m");
2115 static int setup_boot_id(void) {
2116 _cleanup_(unlink_and_freep
) char *from
= NULL
;
2117 _cleanup_free_
char *path
= NULL
;
2118 sd_id128_t rnd
= SD_ID128_NULL
;
2122 /* Generate a new randomized boot ID, so that each boot-up of the container gets a new one */
2124 r
= tempfn_random_child("/run", "proc-sys-kernel-random-boot-id", &path
);
2126 return log_error_errno(r
, "Failed to generate random boot ID path: %m");
2128 r
= sd_id128_randomize(&rnd
);
2130 return log_error_errno(r
, "Failed to generate random boot id: %m");
2132 r
= id128_write(path
, ID128_FORMAT_UUID
, rnd
);
2134 return log_error_errno(r
, "Failed to write boot id: %m");
2136 from
= TAKE_PTR(path
);
2137 to
= "/proc/sys/kernel/random/boot_id";
2139 r
= mount_nofollow_verbose(LOG_ERR
, from
, to
, NULL
, MS_BIND
, NULL
);
2143 return mount_nofollow_verbose(LOG_ERR
, NULL
, to
, NULL
, MS_BIND
|MS_REMOUNT
|MS_RDONLY
|MS_NOSUID
|MS_NOEXEC
|MS_NODEV
, NULL
);
2146 static int copy_devnodes(const char *dest
) {
2147 static const char devnodes
[] =
2160 BLOCK_WITH_UMASK(0000);
2162 /* Create /dev/net, so that we can create /dev/net/tun in it */
2163 if (userns_mkdir(dest
, "/dev/net", 0755, 0, 0) < 0)
2164 return log_error_errno(r
, "Failed to create /dev/net directory: %m");
2166 NULSTR_FOREACH(d
, devnodes
) {
2167 _cleanup_free_
char *from
= NULL
, *to
= NULL
;
2170 from
= path_join("/dev/", d
);
2174 to
= path_join(dest
, from
);
2178 if (stat(from
, &st
) < 0) {
2180 if (errno
!= ENOENT
)
2181 return log_error_errno(errno
, "Failed to stat %s: %m", from
);
2183 } else if (!S_ISCHR(st
.st_mode
) && !S_ISBLK(st
.st_mode
))
2184 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
2185 "%s is not a char or block device, cannot copy.", from
);
2187 _cleanup_free_
char *sl
= NULL
, *prefixed
= NULL
, *dn
= NULL
, *t
= NULL
;
2189 if (mknod(to
, st
.st_mode
, st
.st_rdev
) < 0) {
2190 /* Explicitly warn the user when /dev is already populated. */
2191 if (errno
== EEXIST
)
2192 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
);
2194 return log_error_errno(errno
, "mknod(%s) failed: %m", to
);
2196 /* Some systems abusively restrict mknod but allow bind mounts. */
2199 return log_error_errno(r
, "touch (%s) failed: %m", to
);
2200 r
= mount_nofollow_verbose(LOG_DEBUG
, from
, to
, NULL
, MS_BIND
, NULL
);
2202 return log_error_errno(r
, "Both mknod and bind mount (%s) failed: %m", to
);
2205 r
= userns_lchown(to
, 0, 0);
2207 return log_error_errno(r
, "chown() of device node %s failed: %m", to
);
2209 dn
= path_join("/dev", S_ISCHR(st
.st_mode
) ? "char" : "block");
2213 r
= userns_mkdir(dest
, dn
, 0755, 0, 0);
2215 return log_error_errno(r
, "Failed to create '%s': %m", dn
);
2217 if (asprintf(&sl
, "%s/%u:%u", dn
, major(st
.st_rdev
), minor(st
.st_rdev
)) < 0)
2220 prefixed
= path_join(dest
, sl
);
2224 t
= path_join("..", d
);
2228 if (symlink(t
, prefixed
) < 0)
2229 log_debug_errno(errno
, "Failed to symlink '%s' to '%s': %m", t
, prefixed
);
2236 static int make_extra_nodes(const char *dest
) {
2240 BLOCK_WITH_UMASK(0000);
2242 for (i
= 0; i
< arg_n_extra_nodes
; i
++) {
2243 _cleanup_free_
char *path
= NULL
;
2244 DeviceNode
*n
= arg_extra_nodes
+ i
;
2246 path
= path_join(dest
, n
->path
);
2250 if (mknod(path
, n
->mode
, S_ISCHR(n
->mode
) || S_ISBLK(n
->mode
) ? makedev(n
->major
, n
->minor
) : 0) < 0)
2251 return log_error_errno(errno
, "Failed to create device node '%s': %m", path
);
2253 r
= chmod_and_chown(path
, n
->mode
, n
->uid
, n
->gid
);
2255 return log_error_errno(r
, "Failed to adjust device node ownership of '%s': %m", path
);
2261 static int setup_pts(const char *dest
) {
2262 _cleanup_free_
char *options
= NULL
;
2267 if (arg_selinux_apifs_context
)
2268 (void) asprintf(&options
,
2269 "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT
",context=\"%s\"",
2270 arg_uid_shift
+ TTY_GID
,
2271 arg_selinux_apifs_context
);
2274 (void) asprintf(&options
,
2275 "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT
,
2276 arg_uid_shift
+ TTY_GID
);
2281 /* Mount /dev/pts itself */
2282 p
= prefix_roota(dest
, "/dev/pts");
2283 r
= RET_NERRNO(mkdir(p
, 0755));
2285 return log_error_errno(r
, "Failed to create /dev/pts: %m");
2287 r
= mount_nofollow_verbose(LOG_ERR
, "devpts", p
, "devpts", MS_NOSUID
|MS_NOEXEC
, options
);
2290 r
= userns_lchown(p
, 0, 0);
2292 return log_error_errno(r
, "Failed to chown /dev/pts: %m");
2294 /* Create /dev/ptmx symlink */
2295 p
= prefix_roota(dest
, "/dev/ptmx");
2296 if (symlink("pts/ptmx", p
) < 0)
2297 return log_error_errno(errno
, "Failed to create /dev/ptmx symlink: %m");
2298 r
= userns_lchown(p
, 0, 0);
2300 return log_error_errno(r
, "Failed to chown /dev/ptmx: %m");
2302 /* And fix /dev/pts/ptmx ownership */
2303 p
= prefix_roota(dest
, "/dev/pts/ptmx");
2304 r
= userns_lchown(p
, 0, 0);
2306 return log_error_errno(r
, "Failed to chown /dev/pts/ptmx: %m");
2311 static int setup_stdio_as_dev_console(void) {
2312 _cleanup_close_
int terminal
= -EBADF
;
2315 /* We open the TTY in O_NOCTTY mode, so that we do not become controller yet. We'll do that later
2316 * explicitly, if we are configured to. */
2317 terminal
= open_terminal("/dev/console", O_RDWR
|O_NOCTTY
);
2319 return log_error_errno(terminal
, "Failed to open console: %m");
2321 /* Make sure we can continue logging to the original stderr, even if
2322 * stderr points elsewhere now */
2323 r
= log_dup_console();
2325 return log_error_errno(r
, "Failed to duplicate stderr: %m");
2327 /* invalidates 'terminal' on success and failure */
2328 r
= rearrange_stdio(terminal
, terminal
, terminal
);
2331 return log_error_errno(r
, "Failed to move console to stdin/stdout/stderr: %m");
2336 static int setup_dev_console(const char *console
) {
2337 _cleanup_free_
char *p
= NULL
;
2340 /* Create /dev/console symlink */
2341 r
= path_make_relative("/dev", console
, &p
);
2343 return log_error_errno(r
, "Failed to create relative path: %m");
2345 if (symlink(p
, "/dev/console") < 0)
2346 return log_error_errno(errno
, "Failed to create /dev/console symlink: %m");
2351 static int setup_keyring(void) {
2352 key_serial_t keyring
;
2354 /* Allocate a new session keyring for the container. This makes sure the keyring of the session
2355 * systemd-nspawn was invoked from doesn't leak into the container. Note that by default we block
2356 * keyctl() and request_key() anyway via seccomp so doing this operation isn't strictly necessary,
2357 * but in case people explicitly allow-list these system calls let's make sure we don't leak anything
2358 * into the container. */
2360 keyring
= keyctl(KEYCTL_JOIN_SESSION_KEYRING
, 0, 0, 0, 0);
2361 if (keyring
== -1) {
2362 if (errno
== ENOSYS
)
2363 log_debug_errno(errno
, "Kernel keyring not supported, ignoring.");
2364 else if (ERRNO_IS_PRIVILEGE(errno
))
2365 log_debug_errno(errno
, "Kernel keyring access prohibited, ignoring.");
2367 return log_error_errno(errno
, "Setting up kernel keyring failed: %m");
2373 static int setup_credentials(const char *root
) {
2377 if (arg_n_credentials
<= 0)
2380 r
= userns_mkdir(root
, "/run/host", 0755, 0, 0);
2382 return log_error_errno(r
, "Failed to create /run/host: %m");
2384 r
= userns_mkdir(root
, "/run/host/credentials", 0700, 0, 0);
2386 return log_error_errno(r
, "Failed to create /run/host/credentials: %m");
2388 q
= prefix_roota(root
, "/run/host/credentials");
2389 r
= mount_nofollow_verbose(LOG_ERR
, NULL
, q
, "ramfs", MS_NOSUID
|MS_NOEXEC
|MS_NODEV
, "mode=0700");
2393 for (size_t i
= 0; i
< arg_n_credentials
; i
++) {
2394 _cleanup_free_
char *j
= NULL
;
2395 _cleanup_close_
int fd
= -EBADF
;
2397 j
= path_join(q
, arg_credentials
[i
].id
);
2401 fd
= open(j
, O_CREAT
|O_EXCL
|O_WRONLY
|O_CLOEXEC
|O_NOFOLLOW
, 0600);
2403 return log_error_errno(errno
, "Failed to create credential file %s: %m", j
);
2405 r
= loop_write(fd
, arg_credentials
[i
].data
, arg_credentials
[i
].size
);
2407 return log_error_errno(r
, "Failed to write credential to file %s: %m", j
);
2409 if (fchmod(fd
, 0400) < 0)
2410 return log_error_errno(errno
, "Failed to adjust access mode of %s: %m", j
);
2412 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
2413 if (fchown(fd
, arg_uid_shift
, arg_uid_shift
) < 0)
2414 return log_error_errno(errno
, "Failed to adjust ownership of %s: %m", j
);
2418 if (chmod(q
, 0500) < 0)
2419 return log_error_errno(errno
, "Failed to adjust access mode of %s: %m", q
);
2421 r
= userns_lchown(q
, 0, 0);
2425 /* Make both mount and superblock read-only now */
2426 r
= mount_nofollow_verbose(LOG_ERR
, NULL
, q
, NULL
, MS_REMOUNT
|MS_BIND
|MS_RDONLY
|MS_NOSUID
|MS_NOEXEC
|MS_NODEV
, NULL
);
2430 return mount_nofollow_verbose(LOG_ERR
, NULL
, q
, NULL
, MS_REMOUNT
|MS_RDONLY
|MS_NOSUID
|MS_NOEXEC
|MS_NODEV
, "mode=0500");
2433 static int setup_kmsg(int fd_inner_socket
) {
2434 _cleanup_(unlink_and_freep
) char *from
= NULL
;
2435 _cleanup_free_
char *fifo
= NULL
;
2436 _cleanup_close_
int fd
= -EBADF
;
2439 assert(fd_inner_socket
>= 0);
2441 BLOCK_WITH_UMASK(0000);
2443 /* We create the kmsg FIFO as a temporary file in /run, but immediately delete it after bind mounting it to
2444 * /proc/kmsg. While FIFOs on the reading side behave very similar to /proc/kmsg, their writing side behaves
2445 * differently from /dev/kmsg in that writing blocks when nothing is reading. In order to avoid any problems
2446 * with containers deadlocking due to this we simply make /dev/kmsg unavailable to the container. */
2448 r
= tempfn_random_child("/run", "proc-kmsg", &fifo
);
2450 return log_error_errno(r
, "Failed to generate kmsg path: %m");
2452 if (mkfifo(fifo
, 0600) < 0)
2453 return log_error_errno(errno
, "mkfifo() for /run/kmsg failed: %m");
2455 from
= TAKE_PTR(fifo
);
2457 r
= mount_nofollow_verbose(LOG_ERR
, from
, "/proc/kmsg", NULL
, MS_BIND
, NULL
);
2461 fd
= open(from
, O_RDWR
|O_NONBLOCK
|O_CLOEXEC
);
2463 return log_error_errno(errno
, "Failed to open fifo: %m");
2465 /* Store away the fd in the socket, so that it stays open as long as we run the child */
2466 r
= send_one_fd(fd_inner_socket
, fd
, 0);
2468 return log_error_errno(r
, "Failed to send FIFO fd: %m");
2474 union in_addr_union address4
;
2475 union in_addr_union address6
;
2476 struct FirewallContext
*fw_ctx
;
2479 static int on_address_change(sd_netlink
*rtnl
, sd_netlink_message
*m
, void *userdata
) {
2480 struct ExposeArgs
*args
= ASSERT_PTR(userdata
);
2485 (void) expose_port_execute(rtnl
, &args
->fw_ctx
, arg_expose_ports
, AF_INET
, &args
->address4
);
2486 (void) expose_port_execute(rtnl
, &args
->fw_ctx
, arg_expose_ports
, AF_INET6
, &args
->address6
);
2490 static int setup_hostname(void) {
2493 if ((arg_clone_ns_flags
& CLONE_NEWUTS
) == 0)
2496 r
= sethostname_idempotent(arg_hostname
?: arg_machine
);
2498 return log_error_errno(r
, "Failed to set hostname: %m");
2503 static int setup_journal(const char *directory
) {
2504 _cleanup_free_
char *d
= NULL
;
2510 /* Don't link journals in ephemeral mode */
2514 if (arg_link_journal
== LINK_NO
)
2517 try = arg_link_journal_try
|| arg_link_journal
== LINK_AUTO
;
2519 r
= sd_id128_get_machine(&this_id
);
2521 return log_error_errno(r
, "Failed to retrieve machine ID: %m");
2523 if (sd_id128_equal(arg_uuid
, this_id
)) {
2524 log_full(try ? LOG_WARNING
: LOG_ERR
,
2525 "Host and machine ids are equal (%s): refusing to link journals", SD_ID128_TO_STRING(arg_uuid
));
2531 FOREACH_STRING(dirname
, "/var", "/var/log", "/var/log/journal") {
2532 r
= userns_mkdir(directory
, dirname
, 0755, 0, 0);
2534 bool ignore
= r
== -EROFS
&& try;
2535 log_full_errno(ignore
? LOG_DEBUG
: LOG_ERR
, r
,
2536 "Failed to create %s%s: %m", dirname
, ignore
? ", ignoring" : "");
2537 return ignore
? 0 : r
;
2541 p
= strjoina("/var/log/journal/", SD_ID128_TO_STRING(arg_uuid
));
2542 q
= prefix_roota(directory
, p
);
2544 if (path_is_mount_point(p
, NULL
, 0) > 0) {
2548 return log_error_errno(SYNTHETIC_ERRNO(EEXIST
),
2549 "%s: already a mount point, refusing to use for journal", p
);
2552 if (path_is_mount_point(q
, NULL
, 0) > 0) {
2556 return log_error_errno(SYNTHETIC_ERRNO(EEXIST
),
2557 "%s: already a mount point, refusing to use for journal", q
);
2560 r
= readlink_and_make_absolute(p
, &d
);
2562 if (IN_SET(arg_link_journal
, LINK_GUEST
, LINK_AUTO
) &&
2565 r
= userns_mkdir(directory
, p
, 0755, 0, 0);
2567 log_warning_errno(r
, "Failed to create directory %s: %m", q
);
2572 return log_error_errno(errno
, "Failed to remove symlink %s: %m", p
);
2573 } else if (r
== -EINVAL
) {
2575 if (arg_link_journal
== LINK_GUEST
&&
2578 if (errno
== ENOTDIR
) {
2579 log_error("%s already exists and is neither a symlink nor a directory", p
);
2582 return log_error_errno(errno
, "Failed to remove %s: %m", p
);
2584 } else if (r
!= -ENOENT
)
2585 return log_error_errno(r
, "readlink(%s) failed: %m", p
);
2587 if (arg_link_journal
== LINK_GUEST
) {
2589 if (symlink(q
, p
) < 0) {
2591 log_debug_errno(errno
, "Failed to symlink %s to %s, skipping journal setup: %m", q
, p
);
2594 return log_error_errno(errno
, "Failed to symlink %s to %s: %m", q
, p
);
2597 r
= userns_mkdir(directory
, p
, 0755, 0, 0);
2599 log_warning_errno(r
, "Failed to create directory %s: %m", q
);
2603 if (arg_link_journal
== LINK_HOST
) {
2604 /* don't create parents here — if the host doesn't have
2605 * permanent journal set up, don't force it here */
2607 r
= RET_NERRNO(mkdir(p
, 0755));
2608 if (r
< 0 && r
!= -EEXIST
) {
2610 log_debug_errno(r
, "Failed to create %s, skipping journal setup: %m", p
);
2613 return log_error_errno(r
, "Failed to create %s: %m", p
);
2616 } else if (access(p
, F_OK
) < 0)
2619 if (dir_is_empty(q
, /* ignore_hidden_or_backup= */ false) == 0)
2620 log_warning("%s is not empty, proceeding anyway.", q
);
2622 r
= userns_mkdir(directory
, p
, 0755, 0, 0);
2624 return log_error_errno(r
, "Failed to create %s: %m", q
);
2626 r
= mount_nofollow_verbose(LOG_DEBUG
, p
, q
, NULL
, MS_BIND
, NULL
);
2628 return log_error_errno(errno
, "Failed to bind mount journal from host into guest: %m");
2633 static int drop_capabilities(uid_t uid
) {
2634 CapabilityQuintet q
;
2636 /* Let's initialize all five capability sets to something valid. If the quintet was configured via
2637 * OCI use that, but fill in missing bits. If it wasn't then derive the quintet in full from
2638 * arg_caps_retain. */
2640 if (capability_quintet_is_set(&arg_full_capabilities
)) {
2641 q
= arg_full_capabilities
;
2643 if (q
.bounding
== UINT64_MAX
)
2644 q
.bounding
= uid
== 0 ? arg_caps_retain
: 0;
2646 if (q
.effective
== UINT64_MAX
)
2647 q
.effective
= uid
== 0 ? q
.bounding
: 0;
2649 if (q
.inheritable
== UINT64_MAX
)
2650 q
.inheritable
= uid
== 0 ? q
.bounding
: arg_caps_ambient
;
2652 if (q
.permitted
== UINT64_MAX
)
2653 q
.permitted
= uid
== 0 ? q
.bounding
: arg_caps_ambient
;
2655 if (q
.ambient
== UINT64_MAX
&& ambient_capabilities_supported())
2656 q
.ambient
= arg_caps_ambient
;
2658 if (capability_quintet_mangle(&q
))
2659 return log_error_errno(SYNTHETIC_ERRNO(EPERM
), "Cannot set capabilities that are not in the current bounding set.");
2662 q
= (CapabilityQuintet
) {
2663 .bounding
= arg_caps_retain
,
2664 .effective
= uid
== 0 ? arg_caps_retain
: 0,
2665 .inheritable
= uid
== 0 ? arg_caps_retain
: arg_caps_ambient
,
2666 .permitted
= uid
== 0 ? arg_caps_retain
: arg_caps_ambient
,
2667 .ambient
= ambient_capabilities_supported() ? arg_caps_ambient
: UINT64_MAX
,
2670 /* If we're not using OCI, proceed with mangled capabilities (so we don't error out)
2671 * in order to maintain the same behavior as systemd < 242. */
2672 if (capability_quintet_mangle(&q
))
2673 log_full(arg_quiet
? LOG_DEBUG
: LOG_WARNING
,
2674 "Some capabilities will not be set because they are not in the current bounding set.");
2678 return capability_quintet_enforce(&q
);
2681 static int reset_audit_loginuid(void) {
2682 _cleanup_free_
char *p
= NULL
;
2685 if ((arg_clone_ns_flags
& CLONE_NEWPID
) == 0)
2688 r
= read_one_line_file("/proc/self/loginuid", &p
);
2692 return log_error_errno(r
, "Failed to read /proc/self/loginuid: %m");
2694 /* Already reset? */
2695 if (streq(p
, "4294967295"))
2698 r
= write_string_file("/proc/self/loginuid", "4294967295", WRITE_STRING_FILE_DISABLE_BUFFER
);
2701 "Failed to reset audit login UID. This probably means that your kernel is too\n"
2702 "old and you have audit enabled. Note that the auditing subsystem is known to\n"
2703 "be incompatible with containers on old kernels. Please make sure to upgrade\n"
2704 "your kernel or to off auditing with 'audit=0' on the kernel command line before\n"
2705 "using systemd-nspawn. Sleeping for 5s... (%m)");
2713 static int mount_tunnel_dig(const char *root
) {
2717 (void) mkdir_p("/run/systemd/nspawn/", 0755);
2718 (void) mkdir_p("/run/systemd/nspawn/propagate", 0600);
2719 p
= strjoina("/run/systemd/nspawn/propagate/", arg_machine
);
2720 (void) mkdir_p(p
, 0600);
2722 r
= userns_mkdir(root
, "/run/host", 0755, 0, 0);
2724 return log_error_errno(r
, "Failed to create /run/host: %m");
2726 r
= userns_mkdir(root
, NSPAWN_MOUNT_TUNNEL
, 0600, 0, 0);
2728 return log_error_errno(r
, "Failed to create "NSPAWN_MOUNT_TUNNEL
": %m");
2730 q
= prefix_roota(root
, NSPAWN_MOUNT_TUNNEL
);
2731 r
= mount_nofollow_verbose(LOG_ERR
, p
, q
, NULL
, MS_BIND
, NULL
);
2735 r
= mount_nofollow_verbose(LOG_ERR
, NULL
, q
, NULL
, MS_BIND
|MS_REMOUNT
|MS_RDONLY
, NULL
);
2742 static int mount_tunnel_open(void) {
2745 r
= mount_follow_verbose(LOG_ERR
, NULL
, NSPAWN_MOUNT_TUNNEL
, NULL
, MS_SLAVE
, NULL
);
2752 static int setup_machine_id(const char *directory
) {
2755 /* If the UUID in the container is already set, then that's what counts, and we use. If it isn't set, and the
2756 * caller passed --uuid=, then we'll pass it in the $container_uuid env var to PID 1 of the container. The
2757 * assumption is that PID 1 will then write it to /etc/machine-id to make it persistent. If --uuid= is not
2758 * passed we generate a random UUID, and pass it via $container_uuid. In effect this means that /etc/machine-id
2759 * in the container and our idea of the container UUID will always be in sync (at least if PID 1 in the
2760 * container behaves nicely). */
2762 r
= id128_get_machine(directory
, &arg_uuid
);
2763 if (ERRNO_IS_NEG_MACHINE_ID_UNSET(r
)) {
2764 /* If the file is missing, empty, or uninitialized, we don't mind */
2765 if (sd_id128_is_null(arg_uuid
)) {
2766 r
= sd_id128_randomize(&arg_uuid
);
2768 return log_error_errno(r
, "Failed to acquire randomized machine UUID: %m");
2771 return log_error_errno(r
, "Failed to read machine ID from container image: %m");
2776 static int recursive_chown(const char *directory
, uid_t shift
, uid_t range
) {
2781 if (arg_userns_mode
== USER_NAMESPACE_NO
|| arg_userns_ownership
!= USER_NAMESPACE_OWNERSHIP_CHOWN
)
2784 r
= path_patch_uid(directory
, arg_uid_shift
, arg_uid_range
);
2785 if (r
== -EOPNOTSUPP
)
2786 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.");
2788 return log_error_errno(r
, "Upper 16 bits of root directory UID and GID do not match.");
2790 return log_error_errno(r
, "Failed to adjust UID/GID shift of OS tree: %m");
2792 log_debug("Root directory of image is already owned by the right UID/GID range, skipping recursive chown operation.");
2794 log_debug("Patched directory tree to match UID/GID range.");
2801 * < 0 : wait_for_terminate() failed to get the state of the
2802 * container, the container was terminated by a signal, or
2803 * failed for an unknown reason. No change is made to the
2804 * container argument.
2805 * > 0 : The program executed in the container terminated with an
2806 * error. The exit code of the program executed in the
2807 * container is returned. The container argument has been set
2808 * to CONTAINER_TERMINATED.
2809 * 0 : The container is being rebooted, has been shut down or exited
2810 * successfully. The container argument has been set to either
2811 * CONTAINER_TERMINATED or CONTAINER_REBOOTED.
2813 * That is, success is indicated by a return value of zero, and an
2814 * error is indicated by a non-zero value.
2816 static int wait_for_container(pid_t pid
, ContainerStatus
*container
) {
2820 r
= wait_for_terminate(pid
, &status
);
2822 return log_warning_errno(r
, "Failed to wait for container: %m");
2824 switch (status
.si_code
) {
2827 if (status
.si_status
== 0)
2828 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
, "Container %s exited successfully.", arg_machine
);
2830 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
, "Container %s failed with error code %i.", arg_machine
, status
.si_status
);
2832 *container
= CONTAINER_TERMINATED
;
2833 return status
.si_status
;
2836 if (status
.si_status
== SIGINT
) {
2837 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
, "Container %s has been shut down.", arg_machine
);
2838 *container
= CONTAINER_TERMINATED
;
2841 } else if (status
.si_status
== SIGHUP
) {
2842 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
, "Container %s is being rebooted.", arg_machine
);
2843 *container
= CONTAINER_REBOOTED
;
2849 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
2850 "Container %s terminated by signal %s.", arg_machine
, signal_to_string(status
.si_status
));
2853 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
2854 "Container %s failed due to unknown reason.", arg_machine
);
2858 static int on_orderly_shutdown(sd_event_source
*s
, const struct signalfd_siginfo
*si
, void *userdata
) {
2861 pid
= PTR_TO_PID(userdata
);
2863 if (kill(pid
, arg_kill_signal
) >= 0) {
2864 log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
2865 sd_event_source_set_userdata(s
, NULL
);
2870 sd_event_exit(sd_event_source_get_event(s
), 0);
2874 static int on_sigchld(sd_event_source
*s
, const struct signalfd_siginfo
*ssi
, void *userdata
) {
2880 pid
= PTR_TO_PID(userdata
);
2885 if (waitid(P_ALL
, 0, &si
, WNOHANG
|WNOWAIT
|WEXITED
) < 0)
2886 return log_error_errno(errno
, "Failed to waitid(): %m");
2887 if (si
.si_pid
== 0) /* No pending children. */
2889 if (si
.si_pid
== pid
) {
2890 /* The main process we care for has exited. Return from
2891 * signal handler but leave the zombie. */
2892 sd_event_exit(sd_event_source_get_event(s
), 0);
2896 /* Reap all other children. */
2897 (void) waitid(P_PID
, si
.si_pid
, &si
, WNOHANG
|WEXITED
);
2903 static int on_request_stop(sd_bus_message
*m
, void *userdata
, sd_bus_error
*error
) {
2908 pid
= PTR_TO_PID(userdata
);
2910 if (arg_kill_signal
> 0) {
2911 log_info("Container termination requested. Attempting to halt container.");
2912 (void) kill(pid
, arg_kill_signal
);
2914 log_info("Container termination requested. Exiting.");
2915 sd_event_exit(sd_bus_get_event(sd_bus_message_get_bus(m
)), 0);
2921 static int determine_names(void) {
2924 if (arg_template
&& !arg_directory
&& arg_machine
) {
2926 /* If --template= was specified then we should not
2927 * search for a machine, but instead create a new one
2928 * in /var/lib/machine. */
2930 arg_directory
= path_join("/var/lib/machines", arg_machine
);
2935 if (!arg_image
&& !arg_directory
) {
2937 _cleanup_(image_unrefp
) Image
*i
= NULL
;
2939 r
= image_find(IMAGE_MACHINE
, arg_machine
, NULL
, &i
);
2941 return log_error_errno(r
, "No image for machine '%s'.", arg_machine
);
2943 return log_error_errno(r
, "Failed to find image for machine '%s': %m", arg_machine
);
2945 if (IN_SET(i
->type
, IMAGE_RAW
, IMAGE_BLOCK
))
2946 r
= free_and_strdup(&arg_image
, i
->path
);
2948 r
= free_and_strdup(&arg_directory
, i
->path
);
2953 arg_read_only
= arg_read_only
|| i
->read_only
;
2955 r
= safe_getcwd(&arg_directory
);
2957 return log_error_errno(r
, "Failed to determine current directory: %m");
2960 if (!arg_directory
&& !arg_image
)
2961 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Failed to determine path, please use -D or -i.");
2965 if (arg_directory
&& path_equal(arg_directory
, "/"))
2966 arg_machine
= gethostname_malloc();
2967 else if (arg_image
) {
2970 r
= path_extract_filename(arg_image
, &arg_machine
);
2972 return log_error_errno(r
, "Failed to extract file name from '%s': %m", arg_image
);
2974 /* Truncate suffix if there is one */
2975 e
= endswith(arg_machine
, ".raw");
2979 r
= path_extract_filename(arg_directory
, &arg_machine
);
2981 return log_error_errno(r
, "Failed to extract file name from '%s': %m", arg_directory
);
2984 hostname_cleanup(arg_machine
);
2985 if (!hostname_is_valid(arg_machine
, 0))
2986 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "Failed to determine machine name automatically, please use -M.");
2988 /* Copy the machine name before the random suffix is added below, otherwise we won't be able
2989 * to match fixed config file names. */
2990 arg_settings_filename
= strjoin(arg_machine
, ".nspawn");
2991 if (!arg_settings_filename
)
2994 /* Add a random suffix when this is an ephemeral machine, so that we can run many
2995 * instances at once without manually having to specify -M each time. */
2997 if (strextendf(&arg_machine
, "-%016" PRIx64
, random_u64()) < 0)
3000 arg_settings_filename
= strjoin(arg_machine
, ".nspawn");
3001 if (!arg_settings_filename
)
3008 static int chase_and_update(char **p
, unsigned flags
) {
3017 r
= chase(*p
, NULL
, flags
, &chased
, NULL
);
3019 return log_error_errno(r
, "Failed to resolve path %s: %m", *p
);
3021 return free_and_replace(*p
, chased
);
3024 static int determine_uid_shift(const char *directory
) {
3026 if (arg_userns_mode
== USER_NAMESPACE_NO
) {
3031 if (arg_uid_shift
== UID_INVALID
) {
3034 /* Read the UID shift off the image. Maybe we can reuse this to avoid chowning. */
3036 if (stat(directory
, &st
) < 0)
3037 return log_error_errno(errno
, "Failed to determine UID base of %s: %m", directory
);
3039 arg_uid_shift
= st
.st_uid
& UINT32_C(0xffff0000);
3041 if (arg_uid_shift
!= (st
.st_gid
& UINT32_C(0xffff0000)))
3042 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
3043 "UID and GID base of %s don't match.", directory
);
3045 arg_uid_range
= UINT32_C(0x10000);
3047 if (arg_uid_shift
!= 0) {
3048 /* If the image is shifted already, then we'll fall back to classic chowning, for
3049 * compatibility (and simplicity), or refuse if mapping is explicitly requested. */
3051 if (arg_userns_ownership
== USER_NAMESPACE_OWNERSHIP_AUTO
) {
3052 log_debug("UID base of %s is non-zero, not using UID mapping.", directory
);
3053 arg_userns_ownership
= USER_NAMESPACE_OWNERSHIP_CHOWN
;
3054 } else if (arg_userns_ownership
== USER_NAMESPACE_OWNERSHIP_MAP
)
3055 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
3056 "UID base of %s is not zero, UID mapping not supported.", directory
);
3060 if (!userns_shift_range_valid(arg_uid_shift
, arg_uid_range
))
3061 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
), "UID base too high for UID range.");
3066 static unsigned long effective_clone_ns_flags(void) {
3067 unsigned long flags
= arg_clone_ns_flags
;
3069 if (arg_private_network
)
3070 flags
|= CLONE_NEWNET
;
3072 flags
|= CLONE_NEWCGROUP
;
3073 if (arg_userns_mode
!= USER_NAMESPACE_NO
)
3074 flags
|= CLONE_NEWUSER
;
3079 static int patch_sysctl(void) {
3081 /* This table is inspired by runc's sysctl() function */
3082 static const struct {
3085 unsigned long clone_flags
;
3087 { "kernel.hostname", false, CLONE_NEWUTS
},
3088 { "kernel.domainname", false, CLONE_NEWUTS
},
3089 { "kernel.msgmax", false, CLONE_NEWIPC
},
3090 { "kernel.msgmnb", false, CLONE_NEWIPC
},
3091 { "kernel.msgmni", false, CLONE_NEWIPC
},
3092 { "kernel.sem", false, CLONE_NEWIPC
},
3093 { "kernel.shmall", false, CLONE_NEWIPC
},
3094 { "kernel.shmmax", false, CLONE_NEWIPC
},
3095 { "kernel.shmmni", false, CLONE_NEWIPC
},
3096 { "fs.mqueue.", true, CLONE_NEWIPC
},
3097 { "net.", true, CLONE_NEWNET
},
3100 unsigned long flags
;
3103 flags
= effective_clone_ns_flags();
3105 STRV_FOREACH_PAIR(k
, v
, arg_sysctl
) {
3109 for (i
= 0; i
< ELEMENTSOF(safe_sysctl
); i
++) {
3111 if (!FLAGS_SET(flags
, safe_sysctl
[i
].clone_flags
))
3114 if (safe_sysctl
[i
].prefix
)
3115 good
= startswith(*k
, safe_sysctl
[i
].key
);
3117 good
= streq(*k
, safe_sysctl
[i
].key
);
3124 return log_error_errno(SYNTHETIC_ERRNO(EPERM
), "Refusing to write to sysctl '%s', as it is not safe in the selected namespaces.", *k
);
3126 r
= sysctl_write(*k
, *v
);
3128 return log_error_errno(r
, "Failed to write sysctl '%s': %m", *k
);
3134 static int inner_child(
3136 int fd_inner_socket
,
3138 char **os_release_pairs
) {
3140 _cleanup_free_
char *home
= NULL
;
3143 (char*) "PATH=" DEFAULT_PATH_COMPAT
,
3144 NULL
, /* container */
3149 NULL
, /* container_uuid */
3150 NULL
, /* LISTEN_FDS */
3151 NULL
, /* LISTEN_PID */
3152 NULL
, /* NOTIFY_SOCKET */
3153 NULL
, /* CREDENTIALS_DIRECTORY */
3157 const char *exec_target
;
3158 _cleanup_strv_free_
char **env_use
= NULL
;
3159 int r
, which_failed
;
3161 /* This is the "inner" child process, i.e. the one forked off by the "outer" child process, which is the one
3162 * the container manager itself forked off. At the time of clone() it gained its own CLONE_NEWNS, CLONE_NEWPID,
3163 * CLONE_NEWUTS, CLONE_NEWIPC, CLONE_NEWUSER namespaces. Note that it has its own CLONE_NEWNS namespace,
3164 * separate from the CLONE_NEWNS created for the "outer" child, and also separate from the host's CLONE_NEWNS
3165 * namespace. The reason for having two levels of CLONE_NEWNS namespaces is that the "inner" one is owned by
3166 * the CLONE_NEWUSER namespace of the container, while the "outer" one is owned by the host's CLONE_NEWUSER
3169 * Note at this point we have no CLONE_NEWNET namespace yet. We'll acquire that one later through
3170 * unshare(). See below. */
3173 assert(fd_inner_socket
>= 0);
3175 log_debug("Inner child is initializing.");
3177 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
3178 /* Tell the parent, that it now can write the UID map. */
3179 (void) barrier_place(barrier
); /* #1 */
3181 /* Wait until the parent wrote the UID map */
3182 if (!barrier_place_and_sync(barrier
)) /* #2 */
3183 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Parent died too early");
3185 /* Become the new root user inside our namespace */
3186 r
= reset_uid_gid();
3188 return log_error_errno(r
, "Couldn't become new root: %m");
3190 /* Creating a new user namespace means all MS_SHARED mounts become MS_SLAVE. Let's put them
3191 * back to MS_SHARED here, since that's what we want as defaults. (This will not reconnect
3192 * propagation, but simply create new peer groups for all our mounts). */
3193 r
= mount_follow_verbose(LOG_ERR
, NULL
, "/", NULL
, MS_SHARED
|MS_REC
, NULL
);
3199 arg_mount_settings
| MOUNT_IN_USERNS
,
3201 arg_selinux_apifs_context
);
3205 if (!arg_network_namespace_path
&& arg_private_network
) {
3206 r
= unshare(CLONE_NEWNET
);
3208 return log_error_errno(errno
, "Failed to unshare network namespace: %m");
3210 /* Tell the parent that it can setup network interfaces. */
3211 (void) barrier_place(barrier
); /* #3 */
3214 r
= mount_sysfs(NULL
, arg_mount_settings
);
3218 /* Wait until we are cgroup-ified, so that we
3219 * can mount the right cgroup path writable */
3220 if (!barrier_place_and_sync(barrier
)) /* #4 */
3221 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
),
3222 "Parent died too early");
3225 r
= unshare(CLONE_NEWCGROUP
);
3227 return log_error_errno(errno
, "Failed to unshare cgroup namespace: %m");
3230 arg_unified_cgroup_hierarchy
,
3231 arg_userns_mode
!= USER_NAMESPACE_NO
,
3234 arg_selinux_apifs_context
,
3237 r
= mount_systemd_cgroup_writable("", arg_unified_cgroup_hierarchy
);
3241 r
= setup_boot_id();
3245 r
= setup_kmsg(fd_inner_socket
);
3252 arg_n_custom_mounts
,
3255 arg_selinux_apifs_context
,
3256 MOUNT_NON_ROOT_ONLY
| MOUNT_IN_USERNS
);
3261 return log_error_errno(errno
, "setsid() failed: %m");
3263 if (arg_private_network
)
3264 (void) loopback_setup();
3266 if (arg_expose_ports
) {
3267 r
= expose_port_send_rtnl(fd_inner_socket
);
3272 if (arg_console_mode
!= CONSOLE_PIPE
) {
3273 _cleanup_close_
int master
= -EBADF
;
3274 _cleanup_free_
char *console
= NULL
;
3276 /* Allocate a pty and make it available as /dev/console. */
3277 master
= openpt_allocate(O_RDWR
|O_NONBLOCK
, &console
);
3279 return log_error_errno(master
, "Failed to allocate a pty: %m");
3281 r
= setup_dev_console(console
);
3283 return log_error_errno(r
, "Failed to set up /dev/console: %m");
3285 r
= send_one_fd(fd_inner_socket
, master
, 0);
3287 return log_error_errno(r
, "Failed to send master fd: %m");
3289 r
= setup_stdio_as_dev_console();
3298 if (arg_oom_score_adjust_set
) {
3299 r
= set_oom_score_adjust(arg_oom_score_adjust
);
3301 return log_error_errno(r
, "Failed to adjust OOM score: %m");
3304 if (arg_cpu_set
.set
)
3305 if (sched_setaffinity(0, arg_cpu_set
.allocated
, arg_cpu_set
.set
) < 0)
3306 return log_error_errno(errno
, "Failed to set CPU affinity: %m");
3308 (void) setup_hostname();
3310 if (arg_personality
!= PERSONALITY_INVALID
) {
3311 r
= safe_personality(arg_personality
);
3313 return log_error_errno(r
, "personality() failed: %m");
3314 #ifdef ARCHITECTURE_SECONDARY
3315 } else if (arg_architecture
== ARCHITECTURE_SECONDARY
) {
3316 r
= safe_personality(PER_LINUX32
);
3318 return log_error_errno(r
, "personality() failed: %m");
3320 } else if (!arg_quiet
&& arg_architecture
>= 0 && arg_architecture
!= native_architecture())
3321 log_notice("Selected architecture '%s' not supported natively on the local CPU, assuming "
3322 "invocation with qemu userspace emulator (or equivalent) in effect.",
3323 architecture_to_string(arg_architecture
));
3325 r
= setrlimit_closest_all((const struct rlimit
*const*) arg_rlimit
, &which_failed
);
3327 return log_error_errno(r
, "Failed to apply resource limit RLIMIT_%s: %m", rlimit_to_string(which_failed
));
3332 if (is_seccomp_available()) {
3333 r
= seccomp_load(arg_seccomp
);
3334 if (ERRNO_IS_NEG_SECCOMP_FATAL(r
))
3335 return log_error_errno(r
, "Failed to install seccomp filter: %m");
3337 log_debug_errno(r
, "Failed to install seccomp filter: %m");
3342 r
= setup_seccomp(arg_caps_retain
, arg_syscall_allow_list
, arg_syscall_deny_list
);
3347 if (arg_suppress_sync
) {
3349 r
= seccomp_suppress_sync();
3351 log_debug_errno(r
, "Failed to install sync() suppression seccomp filter, ignoring: %m");
3353 log_debug("systemd is built without SECCOMP support. Ignoring --suppress-sync= command line option and SuppressSync= setting.");
3358 if (arg_selinux_context
)
3359 if (setexeccon(arg_selinux_context
) < 0)
3360 return log_error_errno(errno
, "setexeccon(\"%s\") failed: %m", arg_selinux_context
);
3363 /* Make sure we keep the caps across the uid/gid dropping, so that we can retain some selected caps
3364 * if we need to later on. */
3365 if (prctl(PR_SET_KEEPCAPS
, 1) < 0)
3366 return log_error_errno(errno
, "Failed to set PR_SET_KEEPCAPS: %m");
3368 if (uid_is_valid(arg_uid
) || gid_is_valid(arg_gid
))
3369 r
= change_uid_gid_raw(arg_uid
, arg_gid
, arg_supplementary_gids
, arg_n_supplementary_gids
, arg_console_mode
!= CONSOLE_PIPE
);
3371 r
= change_uid_gid(arg_user
, arg_console_mode
!= CONSOLE_PIPE
, &home
);
3375 r
= drop_capabilities(getuid());
3377 return log_error_errno(r
, "Dropping capabilities failed: %m");
3379 if (arg_no_new_privileges
)
3380 if (prctl(PR_SET_NO_NEW_PRIVS
, 1, 0, 0, 0) < 0)
3381 return log_error_errno(errno
, "Failed to disable new privileges: %m");
3383 /* LXC sets container=lxc, so follow the scheme here */
3384 envp
[n_env
++] = strjoina("container=", arg_container_service_name
);
3386 envp
[n_env
] = strv_find_prefix(environ
, "TERM=");
3390 if (home
|| !uid_is_valid(arg_uid
) || arg_uid
== 0)
3391 if (asprintf(envp
+ n_env
++, "HOME=%s", home
?: "/root") < 0)
3394 if (arg_user
|| !uid_is_valid(arg_uid
) || arg_uid
== 0)
3395 if (asprintf(envp
+ n_env
++, "USER=%s", arg_user
?: "root") < 0 ||
3396 asprintf(envp
+ n_env
++, "LOGNAME=%s", arg_user
?: "root") < 0)
3399 assert(!sd_id128_is_null(arg_uuid
));
3401 if (asprintf(envp
+ n_env
++, "container_uuid=%s", SD_ID128_TO_UUID_STRING(arg_uuid
)) < 0)
3404 if (fdset_size(fds
) > 0) {
3405 r
= fdset_cloexec(fds
, false);
3407 return log_error_errno(r
, "Failed to unset O_CLOEXEC for file descriptors.");
3409 if ((asprintf(envp
+ n_env
++, "LISTEN_FDS=%u", fdset_size(fds
)) < 0) ||
3410 (asprintf(envp
+ n_env
++, "LISTEN_PID=1") < 0))
3413 if (asprintf(envp
+ n_env
++, "NOTIFY_SOCKET=%s", NSPAWN_NOTIFY_SOCKET_PATH
) < 0)
3416 if (arg_n_credentials
> 0) {
3417 envp
[n_env
] = strdup("CREDENTIALS_DIRECTORY=/run/host/credentials");
3423 if (arg_start_mode
!= START_BOOT
) {
3424 envp
[n_env
] = strdup("LANG=" SYSTEMD_NSPAWN_LOCALE
);
3430 env_use
= strv_env_merge(envp
, os_release_pairs
, arg_setenv
);
3434 /* Let the parent know that we are ready and wait until the parent is ready with the setup, too... */
3435 if (!barrier_place_and_sync(barrier
)) /* #5 */
3436 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Parent died too early");
3439 if (chdir(arg_chdir
) < 0)
3440 return log_error_errno(errno
, "Failed to change to specified working directory %s: %m", arg_chdir
);
3442 if (arg_start_mode
== START_PID2
) {
3443 r
= stub_pid1(arg_uuid
);
3448 if (arg_console_mode
!= CONSOLE_PIPE
) {
3449 /* So far our pty wasn't controlled by any process. Finally, it's time to change that, if we
3450 * are configured for that. Acquire it as controlling tty. */
3451 if (ioctl(STDIN_FILENO
, TIOCSCTTY
) < 0)
3452 return log_error_errno(errno
, "Failed to acquire controlling TTY: %m");
3455 log_debug("Inner child completed, invoking payload.");
3457 /* Now, explicitly close the log, so that we then can close all remaining fds. Closing the log explicitly first
3458 * has the benefit that the logging subsystem knows about it, and is thus ready to be reopened should we need
3459 * it again. Note that the other fds closed here are at least the locking and barrier fds. */
3461 log_set_open_when_needed(true);
3462 log_settle_target();
3464 (void) fdset_close_others(fds
);
3466 if (arg_start_mode
== START_BOOT
) {
3470 /* Automatically search for the init system */
3472 m
= strv_length(arg_parameters
);
3473 a
= newa(char*, m
+ 2);
3474 memcpy_safe(a
+ 1, arg_parameters
, m
* sizeof(char*));
3477 FOREACH_STRING(init
,
3478 "/usr/lib/systemd/systemd",
3479 "/lib/systemd/systemd",
3481 a
[0] = (char*) init
;
3482 execve(a
[0], a
, env_use
);
3485 exec_target
= "/usr/lib/systemd/systemd, /lib/systemd/systemd, /sbin/init";
3486 } else if (!strv_isempty(arg_parameters
)) {
3487 const char *dollar_path
;
3489 exec_target
= arg_parameters
[0];
3491 /* Use the user supplied search $PATH if there is one, or DEFAULT_PATH_COMPAT if not to search the
3493 dollar_path
= strv_env_get(env_use
, "PATH");
3495 if (setenv("PATH", dollar_path
, 1) < 0)
3496 return log_error_errno(errno
, "Failed to update $PATH: %m");
3499 execvpe(arg_parameters
[0], arg_parameters
, env_use
);
3502 /* If we cannot change the directory, we'll end up in /, that is expected. */
3503 (void) chdir(home
?: "/root");
3505 execle(DEFAULT_USER_SHELL
, "-" DEFAULT_USER_SHELL_NAME
, NULL
, env_use
);
3506 if (!streq(DEFAULT_USER_SHELL
, "/bin/bash"))
3507 execle("/bin/bash", "-bash", NULL
, env_use
);
3508 if (!streq(DEFAULT_USER_SHELL
, "/bin/sh"))
3509 execle("/bin/sh", "-sh", NULL
, env_use
);
3511 exec_target
= DEFAULT_USER_SHELL
", /bin/bash, /bin/sh";
3514 return log_error_errno(errno
, "execv(%s) failed: %m", exec_target
);
3517 static int setup_notify_child(void) {
3518 _cleanup_close_
int fd
= -EBADF
;
3519 static const union sockaddr_union sa
= {
3520 .un
.sun_family
= AF_UNIX
,
3521 .un
.sun_path
= NSPAWN_NOTIFY_SOCKET_PATH
,
3525 fd
= socket(AF_UNIX
, SOCK_DGRAM
|SOCK_CLOEXEC
|SOCK_NONBLOCK
, 0);
3527 return log_error_errno(errno
, "Failed to allocate notification socket: %m");
3529 (void) mkdir_parents(NSPAWN_NOTIFY_SOCKET_PATH
, 0755);
3530 (void) sockaddr_un_unlink(&sa
.un
);
3532 r
= bind(fd
, &sa
.sa
, SOCKADDR_UN_LEN(sa
.un
));
3534 return log_error_errno(errno
, "bind(" NSPAWN_NOTIFY_SOCKET_PATH
") failed: %m");
3536 r
= userns_lchown(NSPAWN_NOTIFY_SOCKET_PATH
, 0, 0);
3538 return log_error_errno(r
, "Failed to chown " NSPAWN_NOTIFY_SOCKET_PATH
": %m");
3540 r
= setsockopt_int(fd
, SOL_SOCKET
, SO_PASSCRED
, true);
3542 return log_error_errno(r
, "SO_PASSCRED failed: %m");
3547 static int outer_child(
3549 const char *directory
,
3550 DissectedImage
*dissected_image
,
3551 int fd_outer_socket
,
3552 int fd_inner_socket
,
3556 _cleanup_(bind_user_context_freep
) BindUserContext
*bind_user_context
= NULL
;
3557 _cleanup_strv_free_
char **os_release_pairs
= NULL
;
3558 _cleanup_close_
int fd
= -EBADF
, mntns_fd
= -EBADF
;
3565 /* This is the "outer" child process, i.e the one forked off by the container manager itself. It
3566 * already has its own CLONE_NEWNS namespace (which was created by the clone()). It still lives in
3567 * the host's CLONE_NEWPID, CLONE_NEWUTS, CLONE_NEWIPC, CLONE_NEWUSER and CLONE_NEWNET
3568 * namespaces. After it completed a number of initializations a second child (the "inner" one) is
3569 * forked off it, and it exits. */
3573 assert(fd_outer_socket
>= 0);
3574 assert(fd_inner_socket
>= 0);
3576 log_debug("Outer child is initializing.");
3578 r
= load_os_release_pairs_with_prefix("/", "container_host_", &os_release_pairs
);
3580 log_debug_errno(r
, "Failed to read os-release from host for container, ignoring: %m");
3582 if (prctl(PR_SET_PDEATHSIG
, SIGKILL
) < 0)
3583 return log_error_errno(errno
, "PR_SET_PDEATHSIG failed: %m");
3585 r
= reset_audit_loginuid();
3589 /* Mark everything as slave, so that we still receive mounts from the real root, but don't propagate
3590 * mounts to the real root. */
3591 r
= mount_follow_verbose(LOG_ERR
, NULL
, "/", NULL
, MS_SLAVE
|MS_REC
, NULL
);
3595 if (dissected_image
) {
3596 /* If we are operating on a disk image, then mount its root directory now, but leave out the
3597 * rest. We can read the UID shift from it if we need to. Further down we'll mount the rest,
3598 * but then with the uid shift known. That way we can mount VFAT file systems shifted to the
3599 * right place right away. This makes sure ESP partitions and userns are compatible. */
3601 r
= dissected_image_mount_and_warn(
3606 /* userns_fd= */ -EBADF
,
3607 DISSECT_IMAGE_MOUNT_ROOT_ONLY
|
3608 DISSECT_IMAGE_DISCARD_ON_LOOP
|
3609 DISSECT_IMAGE_USR_NO_ROOT
|
3610 (arg_read_only
? DISSECT_IMAGE_READ_ONLY
: DISSECT_IMAGE_FSCK
|DISSECT_IMAGE_GROWFS
)|
3611 (arg_start_mode
== START_BOOT
? DISSECT_IMAGE_VALIDATE_OS
: 0));
3616 r
= determine_uid_shift(directory
);
3620 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
3621 r
= namespace_open(0, NULL
, &mntns_fd
, NULL
, NULL
, NULL
);
3623 return log_error_errno(r
, "Failed to pin outer mount namespace: %m");
3625 l
= send_one_fd(fd_outer_socket
, mntns_fd
, 0);
3627 return log_error_errno(l
, "Failed to send outer mount namespace fd: %m");
3628 mntns_fd
= safe_close(mntns_fd
);
3630 /* Let the parent know which UID shift we read from the image */
3631 l
= send(fd_outer_socket
, &arg_uid_shift
, sizeof(arg_uid_shift
), MSG_NOSIGNAL
);
3633 return log_error_errno(errno
, "Failed to send UID shift: %m");
3634 if (l
!= sizeof(arg_uid_shift
))
3635 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3636 "Short write while sending UID shift.");
3638 if (arg_userns_mode
== USER_NAMESPACE_PICK
) {
3639 /* When we are supposed to pick the UID shift, the parent will check now whether the
3640 * UID shift we just read from the image is available. If yes, it will send the UID
3641 * shift back to us, if not it will pick a different one, and send it back to us. */
3643 l
= recv(fd_outer_socket
, &arg_uid_shift
, sizeof(arg_uid_shift
), 0);
3645 return log_error_errno(errno
, "Failed to recv UID shift: %m");
3646 if (l
!= sizeof(arg_uid_shift
))
3647 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3648 "Short read while receiving UID shift.");
3651 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
,
3652 "Selected user namespace base " UID_FMT
" and range " UID_FMT
".", arg_uid_shift
, arg_uid_range
);
3655 if (path_equal(directory
, "/")) {
3656 /* If the directory we shall boot is the host, let's operate on a bind mount at a different
3657 * place, so that we can make changes to its mount structure (for example, to implement
3658 * --volatile=) without this interfering with our ability to access files such as
3659 * /etc/localtime to copy into the container. Note that we use a fixed place for this
3660 * (instead of a temporary directory, since we are living in our own mount namespace here
3661 * already, and thus don't need to be afraid of colliding with anyone else's mounts). */
3662 (void) mkdir_p("/run/systemd/nspawn-root", 0755);
3664 r
= mount_nofollow_verbose(LOG_ERR
, "/", "/run/systemd/nspawn-root", NULL
, MS_BIND
|MS_REC
, NULL
);
3668 directory
= "/run/systemd/nspawn-root";
3671 /* Make sure we always have a mount that we can move to root later on. */
3672 r
= make_mount_point(directory
);
3676 /* So the whole tree is now MS_SLAVE, i.e. we'll still receive mount/umount events from the host
3677 * mount namespace. For the directory we are going to run our container let's turn this off, so that
3678 * we'll live in our own little world from now on, and propagation from the host may only happen via
3679 * the mount tunnel dir, or not at all. */
3680 r
= mount_follow_verbose(LOG_ERR
, NULL
, directory
, NULL
, MS_PRIVATE
|MS_REC
, NULL
);
3684 r
= setup_pivot_root(
3687 arg_pivot_root_old
);
3691 r
= setup_volatile_mode(
3695 arg_selinux_apifs_context
);
3699 r
= bind_user_prepare(
3704 &arg_custom_mounts
, &arg_n_custom_mounts
,
3705 &bind_user_context
);
3709 if (arg_userns_mode
!= USER_NAMESPACE_NO
&& bind_user_context
) {
3710 /* Send the user maps we determined to the parent, so that it installs it in our user
3711 * namespace UID map table */
3713 for (size_t i
= 0; i
< bind_user_context
->n_data
; i
++) {
3715 bind_user_context
->data
[i
].payload_user
->uid
,
3716 bind_user_context
->data
[i
].host_user
->uid
,
3717 (uid_t
) bind_user_context
->data
[i
].payload_group
->gid
,
3718 (uid_t
) bind_user_context
->data
[i
].host_group
->gid
,
3721 l
= send(fd_outer_socket
, map
, sizeof(map
), MSG_NOSIGNAL
);
3723 return log_error_errno(errno
, "Failed to send user UID map: %m");
3724 if (l
!= sizeof(map
))
3725 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3726 "Short write while sending user UID map.");
3733 arg_n_custom_mounts
,
3736 arg_selinux_apifs_context
,
3741 if (arg_userns_mode
!= USER_NAMESPACE_NO
&&
3742 IN_SET(arg_userns_ownership
, USER_NAMESPACE_OWNERSHIP_MAP
, USER_NAMESPACE_OWNERSHIP_AUTO
) &&
3743 arg_uid_shift
!= 0) {
3744 _cleanup_free_
char *usr_subtree
= NULL
;
3748 dirs
[i
++] = (char*) directory
;
3750 if (dissected_image
&& dissected_image
->partitions
[PARTITION_USR
].found
) {
3751 usr_subtree
= path_join(directory
, "/usr");
3755 dirs
[i
++] = usr_subtree
;
3760 r
= remount_idmap(dirs
, arg_uid_shift
, arg_uid_range
, UID_INVALID
, REMOUNT_IDMAPPING_HOST_ROOT
);
3761 if (r
== -EINVAL
|| ERRNO_IS_NEG_NOT_SUPPORTED(r
)) {
3762 /* This might fail because the kernel or file system doesn't support idmapping. We
3763 * can't really distinguish this nicely, nor do we have any guarantees about the
3764 * error codes we see, could be EOPNOTSUPP or EINVAL. */
3765 if (arg_userns_ownership
!= USER_NAMESPACE_OWNERSHIP_AUTO
)
3766 return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP
),
3767 "ID mapped mounts are apparently not available, sorry.");
3769 log_debug("ID mapped mounts are apparently not available on this kernel or for the selected file system, reverting to recursive chown()ing.");
3770 arg_userns_ownership
= USER_NAMESPACE_OWNERSHIP_CHOWN
;
3772 return log_error_errno(r
, "Failed to set up ID mapped mounts: %m");
3774 log_debug("ID mapped mounts available, making use of them.");
3779 if (dissected_image
) {
3780 /* Now we know the uid shift, let's now mount everything else that might be in the image. */
3781 r
= dissected_image_mount(
3786 /* userns_fd= */ -EBADF
,
3787 DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY
|
3788 DISSECT_IMAGE_DISCARD_ON_LOOP
|
3789 DISSECT_IMAGE_USR_NO_ROOT
|
3790 (arg_read_only
? DISSECT_IMAGE_READ_ONLY
: DISSECT_IMAGE_FSCK
|DISSECT_IMAGE_GROWFS
)|
3791 (idmap
? DISSECT_IMAGE_MOUNT_IDMAPPED
: 0));
3793 return log_error_errno(r
, "File system check for image failed: %m");
3795 return log_error_errno(r
, "Failed to mount image file system: %m");
3798 if (arg_unified_cgroup_hierarchy
== CGROUP_UNIFIED_UNKNOWN
) {
3799 /* OK, we don't know yet which cgroup mode to use yet. Let's figure it out, and tell the parent. */
3801 r
= detect_unified_cgroup_hierarchy_from_image(directory
);
3805 l
= send(fd_outer_socket
, &arg_unified_cgroup_hierarchy
, sizeof(arg_unified_cgroup_hierarchy
), MSG_NOSIGNAL
);
3807 return log_error_errno(errno
, "Failed to send cgroup mode: %m");
3808 if (l
!= sizeof(arg_unified_cgroup_hierarchy
))
3809 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3810 "Short write while sending cgroup mode.");
3813 r
= recursive_chown(directory
, arg_uid_shift
, arg_uid_range
);
3817 r
= base_filesystem_create(directory
, arg_uid_shift
, (gid_t
) arg_uid_shift
);
3821 if (arg_read_only
&& arg_volatile_mode
== VOLATILE_NO
&&
3822 !has_custom_root_mount(arg_custom_mounts
, arg_n_custom_mounts
)) {
3823 r
= bind_remount_recursive(directory
, MS_RDONLY
, MS_RDONLY
, NULL
);
3825 return log_error_errno(r
, "Failed to make tree read-only: %m");
3828 r
= mount_all(directory
,
3831 arg_selinux_apifs_context
);
3835 r
= copy_devnodes(directory
);
3839 r
= make_extra_nodes(directory
);
3843 (void) dev_setup(directory
, arg_uid_shift
, arg_uid_shift
);
3845 p
= prefix_roota(directory
, "/run/host");
3846 (void) make_inaccessible_nodes(p
, arg_uid_shift
, arg_uid_shift
);
3848 r
= setup_pts(directory
);
3852 r
= mount_tunnel_dig(directory
);
3856 r
= setup_keyring();
3860 r
= setup_credentials(directory
);
3864 r
= bind_user_setup(bind_user_context
, directory
);
3871 arg_n_custom_mounts
,
3874 arg_selinux_apifs_context
,
3875 MOUNT_NON_ROOT_ONLY
);
3879 r
= setup_timezone(directory
);
3883 r
= setup_resolv_conf(directory
);
3887 r
= setup_machine_id(directory
);
3891 r
= setup_journal(directory
);
3895 /* The same stuff as the $container env var, but nicely readable for the entire payload */
3896 p
= prefix_roota(directory
, "/run/host/container-manager");
3897 (void) write_string_file(p
, arg_container_service_name
, WRITE_STRING_FILE_CREATE
);
3899 /* The same stuff as the $container_uuid env var */
3900 p
= prefix_roota(directory
, "/run/host/container-uuid");
3901 (void) write_string_filef(p
, WRITE_STRING_FILE_CREATE
, SD_ID128_UUID_FORMAT_STR
, SD_ID128_FORMAT_VAL(arg_uuid
));
3903 if (!arg_use_cgns
) {
3906 arg_unified_cgroup_hierarchy
,
3907 arg_userns_mode
!= USER_NAMESPACE_NO
,
3910 arg_selinux_apifs_context
,
3916 /* Mark everything as shared so our mounts get propagated down. This is required to make new bind
3917 * mounts available in systemd services inside the container that create a new mount namespace. See
3918 * https://github.com/systemd/systemd/issues/3860 Further submounts (such as /dev) done after this
3919 * will inherit the shared propagation mode.
3921 * IMPORTANT: Do not overmount the root directory anymore from now on to enable moving the root
3922 * directory mount to root later on.
3923 * https://github.com/systemd/systemd/issues/3847#issuecomment-562735251
3925 r
= mount_switch_root(directory
, MS_SHARED
);
3927 return log_error_errno(r
, "Failed to move root directory: %m");
3929 /* We finished setting up the rootfs which is a shared mount. The mount tunnel needs to be a
3930 * dependent mount otherwise we can't MS_MOVE mounts that were propagated from the host into
3932 r
= mount_tunnel_open();
3936 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
3937 /* In order to mount procfs and sysfs in an unprivileged container the kernel
3938 * requires that a fully visible instance is already present in the target mount
3939 * namespace. Mount one here so the inner child can mount its own instances. Later
3940 * we umount the temporary instances created here before we actually exec the
3941 * payload. Since the rootfs is shared the umount will propagate into the container.
3942 * Note, the inner child wouldn't be able to unmount the instances on its own since
3943 * it doesn't own the originating mount namespace. IOW, the outer child needs to do
3945 r
= pin_fully_visible_fs();
3950 fd
= setup_notify_child();
3954 pid
= raw_clone(SIGCHLD
|CLONE_NEWNS
|
3955 arg_clone_ns_flags
|
3956 (arg_userns_mode
!= USER_NAMESPACE_NO
? CLONE_NEWUSER
: 0));
3958 return log_error_errno(errno
, "Failed to fork inner child: %m");
3960 fd_outer_socket
= safe_close(fd_outer_socket
);
3962 /* The inner child has all namespaces that are requested, so that we all are owned by the
3963 * user if user namespaces are turned on. */
3965 if (arg_network_namespace_path
) {
3966 r
= namespace_enter(-1, -1, netns_fd
, -1, -1);
3968 return log_error_errno(r
, "Failed to join network namespace: %m");
3971 r
= inner_child(barrier
, fd_inner_socket
, fds
, os_release_pairs
);
3973 _exit(EXIT_FAILURE
);
3975 _exit(EXIT_SUCCESS
);
3978 l
= send(fd_outer_socket
, &pid
, sizeof(pid
), MSG_NOSIGNAL
);
3980 return log_error_errno(errno
, "Failed to send PID: %m");
3981 if (l
!= sizeof(pid
))
3982 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3983 "Short write while sending PID.");
3985 l
= send(fd_outer_socket
, &arg_uuid
, sizeof(arg_uuid
), MSG_NOSIGNAL
);
3987 return log_error_errno(errno
, "Failed to send machine ID: %m");
3988 if (l
!= sizeof(arg_uuid
))
3989 return log_error_errno(SYNTHETIC_ERRNO(EIO
),
3990 "Short write while sending machine ID.");
3992 l
= send_one_fd(fd_outer_socket
, fd
, 0);
3994 return log_error_errno(l
, "Failed to send notify fd: %m");
3996 fd_outer_socket
= safe_close(fd_outer_socket
);
3997 fd_inner_socket
= safe_close(fd_inner_socket
);
3998 netns_fd
= safe_close(netns_fd
);
4003 static int uid_shift_pick(uid_t
*shift
, LockFile
*ret_lock_file
) {
4004 bool tried_hashed
= false;
4005 unsigned n_tries
= 100;
4010 assert(ret_lock_file
);
4011 assert(arg_userns_mode
== USER_NAMESPACE_PICK
);
4012 assert(arg_uid_range
== 0x10000U
);
4016 (void) mkdir("/run/systemd/nspawn-uid", 0755);
4019 char lock_path
[STRLEN("/run/systemd/nspawn-uid/") + DECIMAL_STR_MAX(uid_t
) + 1];
4020 _cleanup_(release_lock_file
) LockFile lf
= LOCK_FILE_INIT
;
4025 if (candidate
< CONTAINER_UID_BASE_MIN
|| candidate
> CONTAINER_UID_BASE_MAX
)
4027 if ((candidate
& UINT32_C(0xFFFF)) != 0)
4030 xsprintf(lock_path
, "/run/systemd/nspawn-uid/" UID_FMT
, candidate
);
4031 r
= make_lock_file(lock_path
, LOCK_EX
|LOCK_NB
, &lf
);
4032 if (r
== -EBUSY
) /* Range already taken by another nspawn instance */
4037 /* Make some superficial checks whether the range is currently known in the user database */
4038 if (getpwuid(candidate
))
4040 if (getpwuid(candidate
+ UINT32_C(0xFFFE)))
4042 if (getgrgid(candidate
))
4044 if (getgrgid(candidate
+ UINT32_C(0xFFFE)))
4047 *ret_lock_file
= lf
;
4048 lf
= (struct LockFile
) LOCK_FILE_INIT
;
4053 if (arg_machine
&& !tried_hashed
) {
4054 /* Try to hash the base from the container name */
4056 static const uint8_t hash_key
[] = {
4057 0xe1, 0x56, 0xe0, 0xf0, 0x4a, 0xf0, 0x41, 0xaf,
4058 0x96, 0x41, 0xcf, 0x41, 0x33, 0x94, 0xff, 0x72
4061 candidate
= (uid_t
) siphash24(arg_machine
, strlen(arg_machine
), hash_key
);
4063 tried_hashed
= true;
4065 random_bytes(&candidate
, sizeof(candidate
));
4067 candidate
= (candidate
% (CONTAINER_UID_BASE_MAX
- CONTAINER_UID_BASE_MIN
)) + CONTAINER_UID_BASE_MIN
;
4068 candidate
&= (uid_t
) UINT32_C(0xFFFF0000);
4072 static int add_one_uid_map(
4074 uid_t container_uid
,
4078 return strextendf(p
,
4079 UID_FMT
" " UID_FMT
" " UID_FMT
"\n",
4080 container_uid
, host_uid
, range
);
4083 static int make_uid_map_string(
4084 const uid_t bind_user_uid
[],
4085 size_t n_bind_user_uid
,
4089 _cleanup_free_
char *s
= NULL
;
4090 uid_t previous_uid
= 0;
4093 assert(n_bind_user_uid
== 0 || bind_user_uid
);
4094 assert(IN_SET(offset
, 0, 2)); /* used to switch between UID and GID map */
4097 /* The bind_user_uid[] array is a series of 4 uid_t values, for each --bind-user= entry one
4098 * quadruplet, consisting of host and container UID + GID. */
4100 for (size_t i
= 0; i
< n_bind_user_uid
; i
++) {
4101 uid_t payload_uid
= bind_user_uid
[i
*4+offset
],
4102 host_uid
= bind_user_uid
[i
*4+offset
+1];
4104 assert(previous_uid
<= payload_uid
);
4105 assert(payload_uid
< arg_uid_range
);
4107 /* Add a range to close the gap to previous entry */
4108 if (payload_uid
> previous_uid
) {
4109 r
= add_one_uid_map(&s
, previous_uid
, arg_uid_shift
+ previous_uid
, payload_uid
- previous_uid
);
4114 /* Map this specific user */
4115 r
= add_one_uid_map(&s
, payload_uid
, host_uid
, 1);
4119 previous_uid
= payload_uid
+ 1;
4122 /* And add a range to close the gap to finish the range */
4123 if (arg_uid_range
> previous_uid
) {
4124 r
= add_one_uid_map(&s
, previous_uid
, arg_uid_shift
+ previous_uid
, arg_uid_range
- previous_uid
);
4135 static int setup_uid_map(
4137 const uid_t bind_user_uid
[],
4138 size_t n_bind_user_uid
) {
4140 char uid_map
[STRLEN("/proc//uid_map") + DECIMAL_STR_MAX(uid_t
) + 1];
4141 _cleanup_free_
char *s
= NULL
;
4146 /* Build the UID map string */
4147 if (make_uid_map_string(bind_user_uid
, n_bind_user_uid
, 0, &s
) < 0) /* offset=0 contains the UID pair */
4150 xsprintf(uid_map
, "/proc/" PID_FMT
"/uid_map", pid
);
4151 r
= write_string_file(uid_map
, s
, WRITE_STRING_FILE_DISABLE_BUFFER
);
4153 return log_error_errno(r
, "Failed to write UID map: %m");
4155 /* And now build the GID map string */
4157 if (make_uid_map_string(bind_user_uid
, n_bind_user_uid
, 2, &s
) < 0) /* offset=2 contains the GID pair */
4160 xsprintf(uid_map
, "/proc/" PID_FMT
"/gid_map", pid
);
4161 r
= write_string_file(uid_map
, s
, WRITE_STRING_FILE_DISABLE_BUFFER
);
4163 return log_error_errno(r
, "Failed to write GID map: %m");
4168 static int nspawn_dispatch_notify_fd(sd_event_source
*source
, int fd
, uint32_t revents
, void *userdata
) {
4169 char buf
[NOTIFY_BUFFER_MAX
+1];
4171 struct iovec iovec
= {
4173 .iov_len
= sizeof(buf
)-1,
4175 CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct ucred
)) +
4176 CMSG_SPACE(sizeof(int) * NOTIFY_FD_MAX
)) control
;
4177 struct msghdr msghdr
= {
4180 .msg_control
= &control
,
4181 .msg_controllen
= sizeof(control
),
4183 struct ucred
*ucred
;
4185 pid_t inner_child_pid
;
4186 _cleanup_strv_free_
char **tags
= NULL
;
4191 inner_child_pid
= PTR_TO_PID(userdata
);
4193 if (revents
!= EPOLLIN
) {
4194 log_warning("Got unexpected poll event for notify fd.");
4198 n
= recvmsg_safe(fd
, &msghdr
, MSG_DONTWAIT
|MSG_CMSG_CLOEXEC
);
4199 if (ERRNO_IS_NEG_TRANSIENT(n
))
4201 else if (n
== -EXFULL
) {
4202 log_warning("Got message with truncated control data (too many fds sent?), ignoring.");
4205 return log_warning_errno(n
, "Couldn't read notification socket: %m");
4207 cmsg_close_all(&msghdr
);
4209 ucred
= CMSG_FIND_DATA(&msghdr
, SOL_SOCKET
, SCM_CREDENTIALS
, struct ucred
);
4210 if (!ucred
|| ucred
->pid
!= inner_child_pid
) {
4211 log_debug("Received notify message without valid credentials. Ignoring.");
4215 if ((size_t) n
>= sizeof(buf
)) {
4216 log_warning("Received notify message exceeded maximum size. Ignoring.");
4221 tags
= strv_split(buf
, "\n\r");
4225 if (strv_contains(tags
, "READY=1")) {
4226 r
= sd_notify(false, "READY=1\n");
4228 log_warning_errno(r
, "Failed to send readiness notification, ignoring: %m");
4231 p
= strv_find_startswith(tags
, "STATUS=");
4233 (void) sd_notifyf(false, "STATUS=Container running: %s", p
);
4238 static int setup_notify_parent(sd_event
*event
, int fd
, pid_t
*inner_child_pid
, sd_event_source
**notify_event_source
) {
4241 r
= sd_event_add_io(event
, notify_event_source
, fd
, EPOLLIN
, nspawn_dispatch_notify_fd
, inner_child_pid
);
4243 return log_error_errno(r
, "Failed to allocate notify event source: %m");
4245 (void) sd_event_source_set_description(*notify_event_source
, "nspawn-notify");
4250 static int merge_settings(Settings
*settings
, const char *path
) {
4256 /* Copy over bits from the settings, unless they have been explicitly masked by command line switches. Note
4257 * that this steals the fields of the Settings* structure, and hence modifies it. */
4259 if ((arg_settings_mask
& SETTING_START_MODE
) == 0 &&
4260 settings
->start_mode
>= 0) {
4261 arg_start_mode
= settings
->start_mode
;
4262 strv_free_and_replace(arg_parameters
, settings
->parameters
);
4265 if ((arg_settings_mask
& SETTING_EPHEMERAL
) == 0 &&
4266 settings
->ephemeral
>= 0)
4267 arg_ephemeral
= settings
->ephemeral
;
4269 if ((arg_settings_mask
& SETTING_DIRECTORY
) == 0 &&
4272 if (!arg_settings_trusted
)
4273 log_warning("Ignoring root directory setting, file %s is not trusted.", path
);
4275 free_and_replace(arg_directory
, settings
->root
);
4278 if ((arg_settings_mask
& SETTING_PIVOT_ROOT
) == 0 &&
4279 settings
->pivot_root_new
) {
4280 free_and_replace(arg_pivot_root_new
, settings
->pivot_root_new
);
4281 free_and_replace(arg_pivot_root_old
, settings
->pivot_root_old
);
4284 if ((arg_settings_mask
& SETTING_WORKING_DIRECTORY
) == 0 &&
4285 settings
->working_directory
)
4286 free_and_replace(arg_chdir
, settings
->working_directory
);
4288 if ((arg_settings_mask
& SETTING_ENVIRONMENT
) == 0 &&
4289 settings
->environment
)
4290 strv_free_and_replace(arg_setenv
, settings
->environment
);
4292 if ((arg_settings_mask
& SETTING_USER
) == 0) {
4295 free_and_replace(arg_user
, settings
->user
);
4297 if (uid_is_valid(settings
->uid
))
4298 arg_uid
= settings
->uid
;
4299 if (gid_is_valid(settings
->gid
))
4300 arg_gid
= settings
->gid
;
4301 if (settings
->n_supplementary_gids
> 0) {
4302 free_and_replace(arg_supplementary_gids
, settings
->supplementary_gids
);
4303 arg_n_supplementary_gids
= settings
->n_supplementary_gids
;
4307 if ((arg_settings_mask
& SETTING_CAPABILITY
) == 0) {
4308 uint64_t plus
, minus
;
4309 uint64_t network_minus
= 0;
4312 /* Note that we copy both the simple plus/minus caps here, and the full quintet from the
4313 * Settings structure */
4315 plus
= settings
->capability
;
4316 minus
= settings
->drop_capability
;
4318 if ((arg_settings_mask
& SETTING_NETWORK
) == 0 &&
4319 settings_network_configured(settings
)) {
4320 if (settings_private_network(settings
))
4321 plus
|= UINT64_C(1) << CAP_NET_ADMIN
;
4323 network_minus
|= UINT64_C(1) << CAP_NET_ADMIN
;
4326 if (!arg_settings_trusted
&& plus
!= 0) {
4327 if (settings
->capability
!= 0)
4328 log_warning("Ignoring Capability= setting, file %s is not trusted.", path
);
4330 arg_caps_retain
&= ~network_minus
;
4331 arg_caps_retain
|= plus
;
4334 arg_caps_retain
&= ~minus
;
4336 /* Copy the full capabilities over too */
4337 if (capability_quintet_is_set(&settings
->full_capabilities
)) {
4338 if (!arg_settings_trusted
)
4339 log_warning("Ignoring capability settings, file %s is not trusted.", path
);
4341 arg_full_capabilities
= settings
->full_capabilities
;
4344 ambient
= settings
->ambient_capability
;
4345 if (!arg_settings_trusted
&& ambient
!= 0)
4346 log_warning("Ignoring AmbientCapability= setting, file %s is not trusted.", path
);
4348 arg_caps_ambient
|= ambient
;
4351 if ((arg_settings_mask
& SETTING_KILL_SIGNAL
) == 0 &&
4352 settings
->kill_signal
> 0)
4353 arg_kill_signal
= settings
->kill_signal
;
4355 if ((arg_settings_mask
& SETTING_PERSONALITY
) == 0 &&
4356 settings
->personality
!= PERSONALITY_INVALID
)
4357 arg_personality
= settings
->personality
;
4359 if ((arg_settings_mask
& SETTING_MACHINE_ID
) == 0 &&
4360 !sd_id128_is_null(settings
->machine_id
)) {
4362 if (!arg_settings_trusted
)
4363 log_warning("Ignoring MachineID= setting, file %s is not trusted.", path
);
4365 arg_uuid
= settings
->machine_id
;
4368 if ((arg_settings_mask
& SETTING_READ_ONLY
) == 0 &&
4369 settings
->read_only
>= 0)
4370 arg_read_only
= settings
->read_only
;
4372 if ((arg_settings_mask
& SETTING_VOLATILE_MODE
) == 0 &&
4373 settings
->volatile_mode
!= _VOLATILE_MODE_INVALID
)
4374 arg_volatile_mode
= settings
->volatile_mode
;
4376 if ((arg_settings_mask
& SETTING_CUSTOM_MOUNTS
) == 0 &&
4377 settings
->n_custom_mounts
> 0) {
4379 if (!arg_settings_trusted
)
4380 log_warning("Ignoring TemporaryFileSystem=, Bind= and BindReadOnly= settings, file %s is not trusted.", path
);
4382 custom_mount_free_all(arg_custom_mounts
, arg_n_custom_mounts
);
4383 arg_custom_mounts
= TAKE_PTR(settings
->custom_mounts
);
4384 arg_n_custom_mounts
= settings
->n_custom_mounts
;
4385 settings
->n_custom_mounts
= 0;
4389 if ((arg_settings_mask
& SETTING_NETWORK
) == 0 &&
4390 settings_network_configured(settings
)) {
4392 if (!arg_settings_trusted
)
4393 log_warning("Ignoring network settings, file %s is not trusted.", path
);
4395 arg_network_veth
= settings_network_veth(settings
);
4396 arg_private_network
= settings_private_network(settings
);
4398 strv_free_and_replace(arg_network_interfaces
, settings
->network_interfaces
);
4399 strv_free_and_replace(arg_network_macvlan
, settings
->network_macvlan
);
4400 strv_free_and_replace(arg_network_ipvlan
, settings
->network_ipvlan
);
4401 strv_free_and_replace(arg_network_veth_extra
, settings
->network_veth_extra
);
4403 free_and_replace(arg_network_bridge
, settings
->network_bridge
);
4404 free_and_replace(arg_network_zone
, settings
->network_zone
);
4406 free_and_replace(arg_network_namespace_path
, settings
->network_namespace_path
);
4410 if ((arg_settings_mask
& SETTING_EXPOSE_PORTS
) == 0 &&
4411 settings
->expose_ports
) {
4413 if (!arg_settings_trusted
)
4414 log_warning("Ignoring Port= setting, file %s is not trusted.", path
);
4416 expose_port_free_all(arg_expose_ports
);
4417 arg_expose_ports
= TAKE_PTR(settings
->expose_ports
);
4421 if ((arg_settings_mask
& SETTING_USERNS
) == 0 &&
4422 settings
->userns_mode
!= _USER_NAMESPACE_MODE_INVALID
) {
4424 if (!arg_settings_trusted
)
4425 log_warning("Ignoring PrivateUsers= and PrivateUsersChown= settings, file %s is not trusted.", path
);
4427 arg_userns_mode
= settings
->userns_mode
;
4428 arg_uid_shift
= settings
->uid_shift
;
4429 arg_uid_range
= settings
->uid_range
;
4430 arg_userns_ownership
= settings
->userns_ownership
;
4434 if ((arg_settings_mask
& SETTING_BIND_USER
) == 0 &&
4435 !strv_isempty(settings
->bind_user
))
4436 strv_free_and_replace(arg_bind_user
, settings
->bind_user
);
4438 if ((arg_settings_mask
& SETTING_NOTIFY_READY
) == 0 &&
4439 settings
->notify_ready
>= 0)
4440 arg_notify_ready
= settings
->notify_ready
;
4442 if ((arg_settings_mask
& SETTING_SYSCALL_FILTER
) == 0) {
4444 if (!strv_isempty(settings
->syscall_allow_list
) || !strv_isempty(settings
->syscall_deny_list
)) {
4445 if (!arg_settings_trusted
&& !strv_isempty(settings
->syscall_allow_list
))
4446 log_warning("Ignoring SystemCallFilter= settings, file %s is not trusted.", path
);
4448 strv_free_and_replace(arg_syscall_allow_list
, settings
->syscall_allow_list
);
4449 strv_free_and_replace(arg_syscall_deny_list
, settings
->syscall_deny_list
);
4454 if (settings
->seccomp
) {
4455 if (!arg_settings_trusted
)
4456 log_warning("Ignoring SECCOMP filter, file %s is not trusted.", path
);
4458 seccomp_release(arg_seccomp
);
4459 arg_seccomp
= TAKE_PTR(settings
->seccomp
);
4465 for (rl
= 0; rl
< _RLIMIT_MAX
; rl
++) {
4466 if ((arg_settings_mask
& (SETTING_RLIMIT_FIRST
<< rl
)))
4469 if (!settings
->rlimit
[rl
])
4472 if (!arg_settings_trusted
) {
4473 log_warning("Ignoring Limit%s= setting, file '%s' is not trusted.", rlimit_to_string(rl
), path
);
4477 free_and_replace(arg_rlimit
[rl
], settings
->rlimit
[rl
]);
4480 if ((arg_settings_mask
& SETTING_HOSTNAME
) == 0 &&
4482 free_and_replace(arg_hostname
, settings
->hostname
);
4484 if ((arg_settings_mask
& SETTING_NO_NEW_PRIVILEGES
) == 0 &&
4485 settings
->no_new_privileges
>= 0)
4486 arg_no_new_privileges
= settings
->no_new_privileges
;
4488 if ((arg_settings_mask
& SETTING_OOM_SCORE_ADJUST
) == 0 &&
4489 settings
->oom_score_adjust_set
) {
4491 if (!arg_settings_trusted
)
4492 log_warning("Ignoring OOMScoreAdjust= setting, file '%s' is not trusted.", path
);
4494 arg_oom_score_adjust
= settings
->oom_score_adjust
;
4495 arg_oom_score_adjust_set
= true;
4499 if ((arg_settings_mask
& SETTING_CPU_AFFINITY
) == 0 &&
4500 settings
->cpu_set
.set
) {
4502 if (!arg_settings_trusted
)
4503 log_warning("Ignoring CPUAffinity= setting, file '%s' is not trusted.", path
);
4505 cpu_set_reset(&arg_cpu_set
);
4506 arg_cpu_set
= TAKE_STRUCT(settings
->cpu_set
);
4510 if ((arg_settings_mask
& SETTING_RESOLV_CONF
) == 0 &&
4511 settings
->resolv_conf
!= _RESOLV_CONF_MODE_INVALID
)
4512 arg_resolv_conf
= settings
->resolv_conf
;
4514 if ((arg_settings_mask
& SETTING_LINK_JOURNAL
) == 0 &&
4515 settings
->link_journal
!= _LINK_JOURNAL_INVALID
) {
4517 if (!arg_settings_trusted
)
4518 log_warning("Ignoring journal link setting, file '%s' is not trusted.", path
);
4520 arg_link_journal
= settings
->link_journal
;
4521 arg_link_journal_try
= settings
->link_journal_try
;
4525 if ((arg_settings_mask
& SETTING_TIMEZONE
) == 0 &&
4526 settings
->timezone
!= _TIMEZONE_MODE_INVALID
)
4527 arg_timezone
= settings
->timezone
;
4529 if ((arg_settings_mask
& SETTING_SLICE
) == 0 &&
4532 if (!arg_settings_trusted
)
4533 log_warning("Ignoring slice setting, file '%s' is not trusted.", path
);
4535 free_and_replace(arg_slice
, settings
->slice
);
4538 if ((arg_settings_mask
& SETTING_USE_CGNS
) == 0 &&
4539 settings
->use_cgns
>= 0) {
4541 if (!arg_settings_trusted
)
4542 log_warning("Ignoring cgroup namespace setting, file '%s' is not trusted.", path
);
4544 arg_use_cgns
= settings
->use_cgns
;
4547 if ((arg_settings_mask
& SETTING_CLONE_NS_FLAGS
) == 0 &&
4548 settings
->clone_ns_flags
!= ULONG_MAX
) {
4550 if (!arg_settings_trusted
)
4551 log_warning("Ignoring namespace setting, file '%s' is not trusted.", path
);
4553 arg_clone_ns_flags
= settings
->clone_ns_flags
;
4556 if ((arg_settings_mask
& SETTING_CONSOLE_MODE
) == 0 &&
4557 settings
->console_mode
>= 0) {
4559 if (!arg_settings_trusted
)
4560 log_warning("Ignoring console mode setting, file '%s' is not trusted.", path
);
4562 arg_console_mode
= settings
->console_mode
;
4565 if ((arg_settings_mask
& SETTING_SUPPRESS_SYNC
) == 0 &&
4566 settings
->suppress_sync
>= 0)
4567 arg_suppress_sync
= settings
->suppress_sync
;
4569 /* The following properties can only be set through the OCI settings logic, not from the command line, hence we
4570 * don't consult arg_settings_mask for them. */
4572 sd_bus_message_unref(arg_property_message
);
4573 arg_property_message
= TAKE_PTR(settings
->properties
);
4575 arg_console_width
= settings
->console_width
;
4576 arg_console_height
= settings
->console_height
;
4578 device_node_array_free(arg_extra_nodes
, arg_n_extra_nodes
);
4579 arg_extra_nodes
= TAKE_PTR(settings
->extra_nodes
);
4580 arg_n_extra_nodes
= settings
->n_extra_nodes
;
4581 settings
->n_extra_nodes
= 0;
4586 static int load_settings(void) {
4587 _cleanup_(settings_freep
) Settings
*settings
= NULL
;
4588 _cleanup_fclose_
FILE *f
= NULL
;
4589 _cleanup_free_
char *p
= NULL
;
4595 /* If all settings are masked, there's no point in looking for
4596 * the settings file */
4597 if (FLAGS_SET(arg_settings_mask
, _SETTINGS_MASK_ALL
))
4600 /* We first look in the admin's directories in /etc and /run */
4601 FOREACH_STRING(i
, "/etc/systemd/nspawn", "/run/systemd/nspawn") {
4602 _cleanup_free_
char *j
= NULL
;
4604 j
= path_join(i
, arg_settings_filename
);
4612 /* By default, we trust configuration from /etc and /run */
4613 if (arg_settings_trusted
< 0)
4614 arg_settings_trusted
= true;
4619 if (errno
!= ENOENT
)
4620 return log_error_errno(errno
, "Failed to open %s: %m", j
);
4624 /* After that, let's look for a file next to the
4625 * actual image we shall boot. */
4628 r
= file_in_same_dir(arg_image
, arg_settings_filename
, &p
);
4630 return log_error_errno(r
, "Failed to generate settings path from image path: %m");
4631 } else if (arg_directory
) {
4632 r
= file_in_same_dir(arg_directory
, arg_settings_filename
, &p
);
4633 if (r
< 0 && r
!= -EADDRNOTAVAIL
) /* if directory is root fs, don't complain */
4634 return log_error_errno(r
, "Failed to generate settings path from directory path: %m");
4639 if (!f
&& errno
!= ENOENT
)
4640 return log_error_errno(errno
, "Failed to open %s: %m", p
);
4642 /* By default, we do not trust configuration from /var/lib/machines */
4643 if (arg_settings_trusted
< 0)
4644 arg_settings_trusted
= false;
4651 log_debug("Settings are trusted: %s", yes_no(arg_settings_trusted
));
4653 r
= settings_load(f
, p
, &settings
);
4657 return merge_settings(settings
, p
);
4660 static int load_oci_bundle(void) {
4661 _cleanup_(settings_freep
) Settings
*settings
= NULL
;
4664 if (!arg_oci_bundle
)
4667 /* By default let's trust OCI bundles */
4668 if (arg_settings_trusted
< 0)
4669 arg_settings_trusted
= true;
4671 r
= oci_load(NULL
, arg_oci_bundle
, &settings
);
4675 return merge_settings(settings
, arg_oci_bundle
);
4678 static int run_container(
4679 DissectedImage
*dissected_image
,
4681 char veth_name
[IFNAMSIZ
], bool *veth_created
,
4682 struct ExposeArgs
*expose_args
,
4683 int *master
, pid_t
*pid
, int *ret
) {
4685 static const struct sigaction sa
= {
4686 .sa_handler
= nop_signal_handler
,
4687 .sa_flags
= SA_NOCLDSTOP
|SA_RESTART
,
4690 _cleanup_(release_lock_file
) LockFile uid_shift_lock
= LOCK_FILE_INIT
;
4691 _cleanup_close_
int etc_passwd_lock
= -EBADF
;
4692 _cleanup_close_pair_
int
4693 fd_inner_socket_pair
[2] = EBADF_PAIR
,
4694 fd_outer_socket_pair
[2] = EBADF_PAIR
;
4696 _cleanup_close_
int notify_socket
= -EBADF
, mntns_fd
= -EBADF
, fd_kmsg_fifo
= -EBADF
;
4697 _cleanup_(barrier_destroy
) Barrier barrier
= BARRIER_NULL
;
4698 _cleanup_(sd_event_source_unrefp
) sd_event_source
*notify_event_source
= NULL
;
4699 _cleanup_(sd_event_unrefp
) sd_event
*event
= NULL
;
4700 _cleanup_(pty_forward_freep
) PTYForward
*forward
= NULL
;
4701 _cleanup_(sd_netlink_unrefp
) sd_netlink
*rtnl
= NULL
;
4702 _cleanup_(sd_bus_flush_close_unrefp
) sd_bus
*bus
= NULL
;
4703 _cleanup_free_ uid_t
*bind_user_uid
= NULL
;
4704 size_t n_bind_user_uid
= 0;
4705 ContainerStatus container_status
= 0;
4709 _cleanup_close_
int child_netns_fd
= -EBADF
;
4711 assert_se(sigemptyset(&mask_chld
) == 0);
4712 assert_se(sigaddset(&mask_chld
, SIGCHLD
) == 0);
4714 if (arg_userns_mode
== USER_NAMESPACE_PICK
) {
4715 /* When we shall pick the UID/GID range, let's first lock /etc/passwd, so that we can safely
4716 * check with getpwuid() if the specific user already exists. Note that /etc might be
4717 * read-only, in which case this will fail with EROFS. But that's really OK, as in that case we
4718 * can be reasonably sure that no users are going to be added. Note that getpwuid() checks are
4719 * really just an extra safety net. We kinda assume that the UID range we allocate from is
4722 etc_passwd_lock
= take_etc_passwd_lock(NULL
);
4723 if (etc_passwd_lock
< 0 && etc_passwd_lock
!= -EROFS
)
4724 return log_error_errno(etc_passwd_lock
, "Failed to take /etc/passwd lock: %m");
4727 r
= barrier_create(&barrier
);
4729 return log_error_errno(r
, "Cannot initialize IPC barrier: %m");
4731 if (socketpair(AF_UNIX
, SOCK_SEQPACKET
|SOCK_CLOEXEC
, 0, fd_inner_socket_pair
) < 0)
4732 return log_error_errno(errno
, "Failed to create inner socket pair: %m");
4734 if (socketpair(AF_UNIX
, SOCK_SEQPACKET
|SOCK_CLOEXEC
, 0, fd_outer_socket_pair
) < 0)
4735 return log_error_errno(errno
, "Failed to create outer socket pair: %m");
4737 /* Child can be killed before execv(), so handle SIGCHLD in order to interrupt
4738 * parent's blocking calls and give it a chance to call wait() and terminate. */
4739 r
= sigprocmask(SIG_UNBLOCK
, &mask_chld
, NULL
);
4741 return log_error_errno(errno
, "Failed to change the signal mask: %m");
4743 r
= sigaction(SIGCHLD
, &sa
, NULL
);
4745 return log_error_errno(errno
, "Failed to install SIGCHLD handler: %m");
4747 if (arg_network_namespace_path
) {
4748 child_netns_fd
= open(arg_network_namespace_path
, O_RDONLY
|O_NOCTTY
|O_CLOEXEC
);
4749 if (child_netns_fd
< 0)
4750 return log_error_errno(errno
, "Cannot open file %s: %m", arg_network_namespace_path
);
4752 r
= fd_is_ns(child_netns_fd
, CLONE_NEWNET
);
4754 log_debug_errno(r
, "Cannot determine if passed network namespace path '%s' really refers to a network namespace, assuming it does.", arg_network_namespace_path
);
4756 return log_error_errno(r
, "Failed to check %s fs type: %m", arg_network_namespace_path
);
4758 return log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
4759 "Path %s doesn't refer to a network namespace, refusing.", arg_network_namespace_path
);
4762 *pid
= raw_clone(SIGCHLD
|CLONE_NEWNS
);
4764 return log_error_errno(errno
, "clone() failed%s: %m",
4766 ", do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in)" : "");
4769 /* The outer child only has a file system namespace. */
4770 barrier_set_role(&barrier
, BARRIER_CHILD
);
4772 fd_inner_socket_pair
[0] = safe_close(fd_inner_socket_pair
[0]);
4773 fd_outer_socket_pair
[0] = safe_close(fd_outer_socket_pair
[0]);
4775 (void) reset_all_signal_handlers();
4776 (void) reset_signal_mask();
4778 r
= outer_child(&barrier
,
4781 fd_outer_socket_pair
[1],
4782 fd_inner_socket_pair
[1],
4786 _exit(EXIT_FAILURE
);
4788 _exit(EXIT_SUCCESS
);
4791 barrier_set_role(&barrier
, BARRIER_PARENT
);
4795 fd_inner_socket_pair
[1] = safe_close(fd_inner_socket_pair
[1]);
4796 fd_outer_socket_pair
[1] = safe_close(fd_outer_socket_pair
[1]);
4798 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
4799 mntns_fd
= receive_one_fd(fd_outer_socket_pair
[0], 0);
4801 return log_error_errno(mntns_fd
, "Failed to receive mount namespace fd from outer child: %m");
4803 /* The child just let us know the UID shift it might have read from the image. */
4804 l
= recv(fd_outer_socket_pair
[0], &arg_uid_shift
, sizeof arg_uid_shift
, 0);
4806 return log_error_errno(errno
, "Failed to read UID shift: %m");
4807 if (l
!= sizeof arg_uid_shift
)
4808 return log_error_errno(SYNTHETIC_ERRNO(EIO
), "Short read while reading UID shift.");
4810 if (arg_userns_mode
== USER_NAMESPACE_PICK
) {
4811 /* If we are supposed to pick the UID shift, let's try to use the shift read from the
4812 * image, but if that's already in use, pick a new one, and report back to the child,
4813 * which one we now picked. */
4815 r
= uid_shift_pick(&arg_uid_shift
, &uid_shift_lock
);
4817 return log_error_errno(r
, "Failed to pick suitable UID/GID range: %m");
4819 l
= send(fd_outer_socket_pair
[0], &arg_uid_shift
, sizeof arg_uid_shift
, MSG_NOSIGNAL
);
4821 return log_error_errno(errno
, "Failed to send UID shift: %m");
4822 if (l
!= sizeof arg_uid_shift
)
4823 return log_error_errno(SYNTHETIC_ERRNO(EIO
), "Short write while writing UID shift.");
4826 n_bind_user_uid
= strv_length(arg_bind_user
);
4827 if (n_bind_user_uid
> 0) {
4828 /* Right after the UID shift, we'll receive the list of UID mappings for the
4829 * --bind-user= logic. Always a quadruplet of payload and host UID + GID. */
4831 bind_user_uid
= new(uid_t
, n_bind_user_uid
*4);
4835 for (size_t i
= 0; i
< n_bind_user_uid
; i
++) {
4836 l
= recv(fd_outer_socket_pair
[0], bind_user_uid
+ i
*4, sizeof(uid_t
)*4, 0);
4838 return log_error_errno(errno
, "Failed to read user UID map pair: %m");
4839 if (l
!= sizeof(uid_t
)*4)
4840 return log_full_errno(l
== 0 ? LOG_DEBUG
: LOG_WARNING
,
4841 SYNTHETIC_ERRNO(EIO
),
4842 "Short read while reading bind user UID pairs.");
4847 if (arg_unified_cgroup_hierarchy
== CGROUP_UNIFIED_UNKNOWN
) {
4848 /* The child let us know the support cgroup mode it might have read from the image. */
4849 l
= recv(fd_outer_socket_pair
[0], &arg_unified_cgroup_hierarchy
, sizeof(arg_unified_cgroup_hierarchy
), 0);
4851 return log_error_errno(errno
, "Failed to read cgroup mode: %m");
4852 if (l
!= sizeof(arg_unified_cgroup_hierarchy
))
4853 return log_error_errno(SYNTHETIC_ERRNO(EIO
), "Short read while reading cgroup mode (%zi bytes).%s",
4854 l
, l
== 0 ? " The child is most likely dead." : "");
4857 /* Wait for the outer child. */
4858 r
= wait_for_terminate_and_check("(sd-namespace)", *pid
, WAIT_LOG_ABNORMAL
);
4861 if (r
!= EXIT_SUCCESS
)
4864 /* And now retrieve the PID of the inner child. */
4865 l
= recv(fd_outer_socket_pair
[0], pid
, sizeof *pid
, 0);
4867 return log_error_errno(errno
, "Failed to read inner child PID: %m");
4868 if (l
!= sizeof *pid
)
4869 return log_error_errno(SYNTHETIC_ERRNO(EIO
), "Short read while reading inner child PID.");
4871 /* We also retrieve container UUID in case it was generated by outer child */
4872 l
= recv(fd_outer_socket_pair
[0], &arg_uuid
, sizeof arg_uuid
, 0);
4874 return log_error_errno(errno
, "Failed to read container machine ID: %m");
4875 if (l
!= sizeof(arg_uuid
))
4876 return log_error_errno(SYNTHETIC_ERRNO(EIO
), "Short read while reading container machined ID.");
4878 /* We also retrieve the socket used for notifications generated by outer child */
4879 notify_socket
= receive_one_fd(fd_outer_socket_pair
[0], 0);
4880 if (notify_socket
< 0)
4881 return log_error_errno(notify_socket
,
4882 "Failed to receive notification socket from the outer child: %m");
4884 log_debug("Init process invoked as PID "PID_FMT
, *pid
);
4886 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
4887 if (!barrier_place_and_sync(&barrier
)) /* #1 */
4888 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Child died too early.");
4890 r
= setup_uid_map(*pid
, bind_user_uid
, n_bind_user_uid
);
4894 (void) barrier_place(&barrier
); /* #2 */
4897 if (arg_private_network
) {
4898 if (!arg_network_namespace_path
) {
4899 /* Wait until the child has unshared its network namespace. */
4900 if (!barrier_place_and_sync(&barrier
)) /* #3 */
4901 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Child died too early");
4904 if (child_netns_fd
< 0) {
4905 /* Make sure we have an open file descriptor to the child's network
4906 * namespace so it stays alive even if the child exits. */
4907 r
= namespace_open(*pid
, NULL
, NULL
, &child_netns_fd
, NULL
, NULL
);
4909 return log_error_errno(r
, "Failed to open child network namespace: %m");
4912 r
= move_network_interfaces(child_netns_fd
, arg_network_interfaces
);
4916 if (arg_network_veth
) {
4917 r
= setup_veth(arg_machine
, *pid
, veth_name
,
4918 arg_network_bridge
|| arg_network_zone
, &arg_network_provided_mac
);
4924 if (arg_network_bridge
) {
4925 /* Add the interface to a bridge */
4926 r
= setup_bridge(veth_name
, arg_network_bridge
, false);
4931 } else if (arg_network_zone
) {
4932 /* Add the interface to a bridge, possibly creating it */
4933 r
= setup_bridge(veth_name
, arg_network_zone
, true);
4941 r
= setup_veth_extra(arg_machine
, *pid
, arg_network_veth_extra
);
4945 /* We created the primary and extra veth links now; let's remember this, so that we know to
4946 remove them later on. Note that we don't bother with removing veth links that were created
4947 here when their setup failed half-way, because in that case the kernel should be able to
4948 remove them on its own, since they cannot be referenced by anything yet. */
4949 *veth_created
= true;
4951 r
= setup_macvlan(arg_machine
, *pid
, arg_network_macvlan
);
4955 r
= setup_ipvlan(arg_machine
, *pid
, arg_network_ipvlan
);
4960 if (arg_register
|| !arg_keep_unit
) {
4961 r
= sd_bus_default_system(&bus
);
4963 return log_error_errno(r
, "Failed to open system bus: %m");
4965 r
= sd_bus_set_close_on_exit(bus
, false);
4967 return log_error_errno(r
, "Failed to disable close-on-exit behaviour: %m");
4970 if (!arg_keep_unit
) {
4971 /* When a new scope is created for this container, then we'll be registered as its controller, in which
4972 * case PID 1 will send us a friendly RequestStop signal, when it is asked to terminate the
4973 * scope. Let's hook into that, and cleanly shut down the container, and print a friendly message. */
4975 r
= sd_bus_match_signal_async(
4978 "org.freedesktop.systemd1",
4980 "org.freedesktop.systemd1.Scope",
4982 on_request_stop
, NULL
, PID_TO_PTR(*pid
));
4984 return log_error_errno(r
, "Failed to request RequestStop match: %m");
4988 r
= register_machine(
4996 arg_custom_mounts
, arg_n_custom_mounts
,
4999 arg_property_message
,
5001 arg_container_service_name
,
5006 } else if (!arg_keep_unit
) {
5012 arg_custom_mounts
, arg_n_custom_mounts
,
5015 arg_property_message
,
5016 /* allow_pidfds= */ true,
5021 } else if (arg_slice
|| arg_property
)
5022 log_notice("Machine and scope registration turned off, --slice= and --property= settings will have no effect.");
5024 r
= create_subcgroup(*pid
, arg_keep_unit
, arg_unified_cgroup_hierarchy
);
5028 r
= sync_cgroup(*pid
, arg_unified_cgroup_hierarchy
, arg_uid_shift
);
5032 r
= chown_cgroup(*pid
, arg_unified_cgroup_hierarchy
, arg_uid_shift
);
5036 /* Notify the child that the parent is ready with all
5037 * its setup (including cgroup-ification), and that
5038 * the child can now hand over control to the code to
5039 * run inside the container. */
5040 (void) barrier_place(&barrier
); /* #4 */
5042 /* Block SIGCHLD here, before notifying child.
5043 * process_pty() will handle it with the other signals. */
5044 assert_se(sigprocmask(SIG_BLOCK
, &mask_chld
, NULL
) >= 0);
5046 /* Reset signal to default */
5047 r
= default_signals(SIGCHLD
);
5049 return log_error_errno(r
, "Failed to reset SIGCHLD: %m");
5051 r
= sd_event_new(&event
);
5053 return log_error_errno(r
, "Failed to get default event source: %m");
5055 (void) sd_event_set_watchdog(event
, true);
5058 r
= sd_bus_attach_event(bus
, event
, 0);
5060 return log_error_errno(r
, "Failed to attach bus to event loop: %m");
5063 r
= setup_notify_parent(event
, notify_socket
, PID_TO_PTR(*pid
), ¬ify_event_source
);
5067 /* Wait that the child is completely ready now, and has mounted their own copies of procfs and so on,
5068 * before we take the fully visible instances away. */
5069 if (!barrier_sync(&barrier
)) /* #5.1 */
5070 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Child died too early.");
5072 if (arg_userns_mode
!= USER_NAMESPACE_NO
) {
5073 r
= wipe_fully_visible_fs(mntns_fd
);
5076 mntns_fd
= safe_close(mntns_fd
);
5079 /* And now let the child know that we completed removing the procfs instances, and it can start the
5081 if (!barrier_place(&barrier
)) /* #5.2 */
5082 return log_error_errno(SYNTHETIC_ERRNO(ESRCH
), "Child died too early.");
5084 /* At this point we have made use of the UID we picked, and thus nss-systemd/systemd-machined.service
5085 * will make them appear in getpwuid(), thus we can release the /etc/passwd lock. */
5086 etc_passwd_lock
= safe_close(etc_passwd_lock
);
5088 (void) sd_notifyf(false,
5089 "STATUS=Container running.\n"
5090 "X_NSPAWN_LEADER_PID=" PID_FMT
, *pid
);
5091 if (!arg_notify_ready
) {
5092 r
= sd_notify(false, "READY=1\n");
5094 log_warning_errno(r
, "Failed to send readiness notification, ignoring: %m");
5097 if (arg_kill_signal
> 0) {
5098 /* Try to kill the init system on SIGINT or SIGTERM */
5099 (void) sd_event_add_signal(event
, NULL
, SIGINT
, on_orderly_shutdown
, PID_TO_PTR(*pid
));
5100 (void) sd_event_add_signal(event
, NULL
, SIGTERM
, on_orderly_shutdown
, PID_TO_PTR(*pid
));
5102 /* Immediately exit */
5103 (void) sd_event_add_signal(event
, NULL
, SIGINT
, NULL
, NULL
);
5104 (void) sd_event_add_signal(event
, NULL
, SIGTERM
, NULL
, NULL
);
5107 (void) sd_event_add_signal(event
, NULL
, SIGRTMIN
+18, sigrtmin18_handler
, NULL
);
5109 r
= sd_event_add_memory_pressure(event
, NULL
, NULL
, NULL
);
5111 log_debug_errno(r
, "Failed allocate memory pressure event source, ignoring: %m");
5113 /* Exit when the child exits */
5114 (void) sd_event_add_signal(event
, NULL
, SIGCHLD
, on_sigchld
, PID_TO_PTR(*pid
));
5116 /* Retrieve the kmsg fifo allocated by inner child */
5117 fd_kmsg_fifo
= receive_one_fd(fd_inner_socket_pair
[0], 0);
5118 if (fd_kmsg_fifo
< 0)
5119 return log_error_errno(fd_kmsg_fifo
, "Failed to receive kmsg fifo from inner child: %m");
5121 if (arg_expose_ports
) {
5122 r
= expose_port_watch_rtnl(event
, fd_inner_socket_pair
[0], on_address_change
, expose_args
, &rtnl
);
5126 (void) expose_port_execute(rtnl
, &expose_args
->fw_ctx
, arg_expose_ports
, AF_INET
, &expose_args
->address4
);
5127 (void) expose_port_execute(rtnl
, &expose_args
->fw_ctx
, arg_expose_ports
, AF_INET6
, &expose_args
->address6
);
5130 if (arg_console_mode
!= CONSOLE_PIPE
) {
5131 _cleanup_close_
int fd
= -EBADF
;
5132 PTYForwardFlags flags
= 0;
5134 /* Retrieve the master pty allocated by inner child */
5135 fd
= receive_one_fd(fd_inner_socket_pair
[0], 0);
5137 return log_error_errno(fd
, "Failed to receive master pty from the inner child: %m");
5139 switch (arg_console_mode
) {
5141 case CONSOLE_READ_ONLY
:
5142 flags
|= PTY_FORWARD_READ_ONLY
;
5146 case CONSOLE_INTERACTIVE
:
5147 flags
|= PTY_FORWARD_IGNORE_VHANGUP
;
5149 r
= pty_forward_new(event
, fd
, flags
, &forward
);
5151 return log_error_errno(r
, "Failed to create PTY forwarder: %m");
5153 if (arg_console_width
!= UINT_MAX
|| arg_console_height
!= UINT_MAX
)
5154 (void) pty_forward_set_width_height(forward
,
5156 arg_console_height
);
5160 assert(arg_console_mode
== CONSOLE_PASSIVE
);
5163 *master
= TAKE_FD(fd
);
5166 fd_inner_socket_pair
[0] = safe_close(fd_inner_socket_pair
[0]);
5168 r
= sd_event_loop(event
);
5170 return log_error_errno(r
, "Failed to run event loop: %m");
5175 (void) pty_forward_get_last_char(forward
, &last_char
);
5176 forward
= pty_forward_free(forward
);
5178 if (!arg_quiet
&& last_char
!= '\n')
5182 /* Kill if it is not dead yet anyway */
5183 if (!arg_register
&& !arg_keep_unit
&& bus
)
5184 terminate_scope(bus
, arg_machine
);
5186 /* Normally redundant, but better safe than sorry */
5187 (void) kill(*pid
, SIGKILL
);
5189 fd_kmsg_fifo
= safe_close(fd_kmsg_fifo
);
5191 if (arg_private_network
) {
5192 /* Move network interfaces back to the parent network namespace. We use `safe_fork`
5193 * to avoid having to move the parent to the child network namespace. */
5194 r
= safe_fork(NULL
, FORK_RESET_SIGNALS
|FORK_DEATHSIG_SIGTERM
|FORK_WAIT
|FORK_LOG
, NULL
);
5199 _cleanup_close_
int parent_netns_fd
= -EBADF
;
5201 r
= namespace_open(getpid_cached(), NULL
, NULL
, &parent_netns_fd
, NULL
, NULL
);
5203 log_error_errno(r
, "Failed to open parent network namespace: %m");
5204 _exit(EXIT_FAILURE
);
5207 r
= namespace_enter(-1, -1, child_netns_fd
, -1, -1);
5209 log_error_errno(r
, "Failed to enter child network namespace: %m");
5210 _exit(EXIT_FAILURE
);
5213 /* Reverse network interfaces pair list so that interfaces get their initial name back.
5214 * This is about ensuring interfaces get their old name back when being moved back. */
5215 arg_network_interfaces
= strv_reverse(arg_network_interfaces
);
5217 r
= move_network_interfaces(parent_netns_fd
, arg_network_interfaces
);
5219 log_error_errno(r
, "Failed to move network interfaces back to parent network namespace: %m");
5221 _exit(r
< 0 ? EXIT_FAILURE
: EXIT_SUCCESS
);
5225 r
= wait_for_container(TAKE_PID(*pid
), &container_status
);
5227 /* Tell machined that we are gone. */
5229 (void) unregister_machine(bus
, arg_machine
);
5232 /* We failed to wait for the container, or the container exited abnormally. */
5234 if (r
> 0 || container_status
== CONTAINER_TERMINATED
) {
5235 /* r > 0 → The container exited with a non-zero status.
5236 * As a special case, we need to replace 133 with a different value,
5237 * because 133 is special-cased in the service file to reboot the container.
5238 * otherwise → The container exited with zero status and a reboot was not requested.
5240 if (r
== EXIT_FORCE_RESTART
)
5241 r
= EXIT_FAILURE
; /* replace 133 with the general failure code */
5243 return 0; /* finito */
5246 /* CONTAINER_REBOOTED, loop again */
5248 if (arg_keep_unit
) {
5249 /* Special handling if we are running as a service: instead of simply
5250 * restarting the machine we want to restart the entire service, so let's
5251 * inform systemd about this with the special exit code 133. The service
5252 * file uses RestartForceExitStatus=133 so that this results in a full
5253 * nspawn restart. This is necessary since we might have cgroup parameters
5254 * set we want to have flushed out. */
5255 *ret
= EXIT_FORCE_RESTART
;
5256 return 0; /* finito */
5259 expose_port_flush(&expose_args
->fw_ctx
, arg_expose_ports
, AF_INET
, &expose_args
->address4
);
5260 expose_port_flush(&expose_args
->fw_ctx
, arg_expose_ports
, AF_INET6
, &expose_args
->address6
);
5262 (void) remove_veth_links(veth_name
, arg_network_veth_extra
);
5263 *veth_created
= false;
5264 return 1; /* loop again */
5267 static int initialize_rlimits(void) {
5268 /* The default resource limits the kernel passes to PID 1, as per kernel 5.16. Let's pass our container payload
5269 * the same values as the kernel originally passed to PID 1, in order to minimize differences between host and
5270 * container execution environments. */
5272 static const struct rlimit kernel_defaults
[_RLIMIT_MAX
] = {
5273 [RLIMIT_AS
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5274 [RLIMIT_CORE
] = { 0, RLIM_INFINITY
},
5275 [RLIMIT_CPU
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5276 [RLIMIT_DATA
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5277 [RLIMIT_FSIZE
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5278 [RLIMIT_LOCKS
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5279 [RLIMIT_MEMLOCK
] = { DEFAULT_RLIMIT_MEMLOCK
, DEFAULT_RLIMIT_MEMLOCK
},
5280 [RLIMIT_MSGQUEUE
] = { 819200, 819200 },
5281 [RLIMIT_NICE
] = { 0, 0 },
5282 [RLIMIT_NOFILE
] = { 1024, 4096 },
5283 [RLIMIT_RSS
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5284 [RLIMIT_RTPRIO
] = { 0, 0 },
5285 [RLIMIT_RTTIME
] = { RLIM_INFINITY
, RLIM_INFINITY
},
5286 [RLIMIT_STACK
] = { 8388608, RLIM_INFINITY
},
5288 /* The kernel scales the default for RLIMIT_NPROC and RLIMIT_SIGPENDING based on the system's amount of
5289 * RAM. To provide best compatibility we'll read these limits off PID 1 instead of hardcoding them
5290 * here. This is safe as we know that PID 1 doesn't change these two limits and thus the original
5291 * kernel's initialization should still be valid during runtime — at least if PID 1 is systemd. Note
5292 * that PID 1 changes a number of other resource limits during early initialization which is why we
5293 * don't read the other limits from PID 1 but prefer the static table above. */
5298 for (rl
= 0; rl
< _RLIMIT_MAX
; rl
++) {
5299 /* Let's only fill in what the user hasn't explicitly configured anyway */
5300 if ((arg_settings_mask
& (SETTING_RLIMIT_FIRST
<< rl
)) == 0) {
5301 const struct rlimit
*v
;
5302 struct rlimit buffer
;
5304 if (IN_SET(rl
, RLIMIT_NPROC
, RLIMIT_SIGPENDING
)) {
5305 /* For these two let's read the limits off PID 1. See above for an explanation. */
5307 if (prlimit(1, rl
, NULL
, &buffer
) < 0)
5308 return log_error_errno(errno
, "Failed to read resource limit RLIMIT_%s of PID 1: %m", rlimit_to_string(rl
));
5311 } else if (rl
== RLIMIT_NOFILE
) {
5312 /* We nowadays bump RLIMIT_NOFILE's hard limit early in PID 1 for all
5313 * userspace. Given that nspawn containers are often run without our PID 1,
5314 * let's grant the containers a raised RLIMIT_NOFILE hard limit by default,
5315 * so that container userspace gets similar resources as host userspace
5317 buffer
= kernel_defaults
[rl
];
5318 buffer
.rlim_max
= MIN((rlim_t
) read_nr_open(), (rlim_t
) HIGH_RLIMIT_NOFILE
);
5321 v
= kernel_defaults
+ rl
;
5323 arg_rlimit
[rl
] = newdup(struct rlimit
, v
, 1);
5324 if (!arg_rlimit
[rl
])
5328 if (DEBUG_LOGGING
) {
5329 _cleanup_free_
char *k
= NULL
;
5331 (void) rlimit_format(arg_rlimit
[rl
], &k
);
5332 log_debug("Setting RLIMIT_%s to %s.", rlimit_to_string(rl
), k
);
5339 static int cant_be_in_netns(void) {
5340 _cleanup_close_
int fd
= -EBADF
;
5344 /* Check if we are in the same netns as udev. If we aren't, then device monitoring (and thus waiting
5345 * for loopback block devices) won't work, and we will hang. Detect this case and exit early with a
5348 if (!arg_image
) /* only matters if --image= us used, i.e. we actually need to use loopback devices */
5351 fd
= socket(AF_UNIX
, SOCK_SEQPACKET
|SOCK_NONBLOCK
|SOCK_CLOEXEC
, 0);
5353 return log_error_errno(errno
, "Failed to allocate udev control socket: %m");
5355 r
= connect_unix_path(fd
, AT_FDCWD
, "/run/udev/control");
5356 if (r
== -ENOENT
|| ERRNO_IS_NEG_DISCONNECT(r
))
5357 return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP
),
5358 "Sorry, but --image= requires access to the host's /run/ hierarchy, since we need access to udev.");
5360 return log_error_errno(r
, "Failed to connect socket to udev control socket: %m");
5362 r
= getpeercred(fd
, &ucred
);
5364 return log_error_errno(r
, "Failed to determine peer of udev control socket: %m");
5366 r
= in_same_namespace(ucred
.pid
, 0, NAMESPACE_NET
);
5368 return log_error_errno(r
, "Failed to determine network namespace of udev: %m");
5370 return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP
),
5371 "Sorry, but --image= is only supported in the main network namespace, since we need access to udev/AF_NETLINK.");
5375 static int run(int argc
, char *argv
[]) {
5376 bool remove_directory
= false, remove_image
= false, veth_created
= false, remove_tmprootdir
= false;
5377 _cleanup_close_
int master
= -EBADF
;
5378 _cleanup_fdset_free_ FDSet
*fds
= NULL
;
5379 int r
, n_fd_passed
, ret
= EXIT_SUCCESS
;
5380 char veth_name
[IFNAMSIZ
] = "";
5381 struct ExposeArgs expose_args
= {};
5382 _cleanup_(release_lock_file
) LockFile tree_global_lock
= LOCK_FILE_INIT
, tree_local_lock
= LOCK_FILE_INIT
;
5383 char tmprootdir
[] = "/tmp/nspawn-root-XXXXXX";
5384 _cleanup_(loop_device_unrefp
) LoopDevice
*loop
= NULL
;
5385 _cleanup_(dissected_image_unrefp
) DissectedImage
*dissected_image
= NULL
;
5386 _cleanup_(fw_ctx_freep
) FirewallContext
*fw_ctx
= NULL
;
5389 log_parse_environment();
5392 r
= parse_argv(argc
, argv
);
5396 if (geteuid() != 0) {
5397 r
= log_warning_errno(SYNTHETIC_ERRNO(EPERM
),
5398 argc
>= 2 ? "Need to be root." :
5399 "Need to be root (and some arguments are usually required).\nHint: try --help");
5403 r
= cant_be_in_netns();
5407 r
= initialize_rlimits();
5411 r
= load_oci_bundle();
5415 r
= determine_names();
5419 r
= load_settings();
5425 log_error_errno(r
, "Failed to determine whether the unified cgroups hierarchy is used: %m");
5429 r
= verify_arguments();
5433 r
= verify_network_interfaces_initialized();
5437 /* Reapply environment settings. */
5438 (void) detect_unified_cgroup_hierarchy_from_environment();
5440 /* Ignore SIGPIPE here, because we use splice() on the ptyfwd stuff and that will generate SIGPIPE if
5441 * the result is closed. Note that the container payload child will reset signal mask+handler anyway,
5442 * so just turning this off here means we only turn it off in nspawn itself, not any children. */
5443 (void) ignore_signals(SIGPIPE
);
5445 n_fd_passed
= sd_listen_fds(false);
5446 if (n_fd_passed
> 0) {
5447 r
= fdset_new_listen_fds(&fds
, false);
5449 log_error_errno(r
, "Failed to collect file descriptors: %m");
5454 /* The "default" umask. This is appropriate for most file and directory
5455 * operations performed by nspawn, and is the umask that will be used for
5456 * the child. Functions like copy_devnodes() change the umask temporarily. */
5459 if (arg_directory
) {
5462 /* Safety precaution: let's not allow running images from the live host OS image, as long as
5463 * /var from the host will propagate into container dynamically (because bad things happen if
5464 * two systems write to the same /var). Let's allow it for the special cases where /var is
5465 * either copied (i.e. --ephemeral) or replaced (i.e. --volatile=yes|state). */
5466 if (path_equal(arg_directory
, "/") && !(arg_ephemeral
|| IN_SET(arg_volatile_mode
, VOLATILE_YES
, VOLATILE_STATE
))) {
5467 r
= log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
5468 "Spawning container on root directory is not supported. Consider using --ephemeral, --volatile=yes or --volatile=state.");
5472 if (arg_ephemeral
) {
5473 _cleanup_free_
char *np
= NULL
;
5475 r
= chase_and_update(&arg_directory
, 0);
5479 /* If the specified path is a mount point we generate the new snapshot immediately
5480 * inside it under a random name. However if the specified is not a mount point we
5481 * create the new snapshot in the parent directory, just next to it. */
5482 r
= path_is_mount_point(arg_directory
, NULL
, 0);
5484 log_error_errno(r
, "Failed to determine whether directory %s is mount point: %m", arg_directory
);
5488 r
= tempfn_random_child(arg_directory
, "machine.", &np
);
5490 r
= tempfn_random(arg_directory
, "machine.", &np
);
5492 log_error_errno(r
, "Failed to generate name for directory snapshot: %m");
5496 /* We take an exclusive lock on this image, since it's our private, ephemeral copy
5497 * only owned by us and no one else. */
5498 r
= image_path_lock(np
, LOCK_EX
|LOCK_NB
, &tree_global_lock
, &tree_local_lock
);
5500 log_error_errno(r
, "Failed to lock %s: %m", np
);
5505 BLOCK_SIGNALS(SIGINT
);
5506 r
= btrfs_subvol_snapshot_at(AT_FDCWD
, arg_directory
, AT_FDCWD
, np
,
5507 (arg_read_only
? BTRFS_SNAPSHOT_READ_ONLY
: 0) |
5508 BTRFS_SNAPSHOT_FALLBACK_COPY
|
5509 BTRFS_SNAPSHOT_FALLBACK_DIRECTORY
|
5510 BTRFS_SNAPSHOT_RECURSIVE
|
5511 BTRFS_SNAPSHOT_QUOTA
|
5512 BTRFS_SNAPSHOT_SIGINT
);
5515 log_error_errno(r
, "Interrupted while copying file system tree to %s, removed again.", np
);
5519 log_error_errno(r
, "Failed to create snapshot %s from %s: %m", np
, arg_directory
);
5523 free_and_replace(arg_directory
, np
);
5524 remove_directory
= true;
5526 r
= chase_and_update(&arg_directory
, arg_template
? CHASE_NONEXISTENT
: 0);
5530 r
= image_path_lock(arg_directory
, (arg_read_only
? LOCK_SH
: LOCK_EX
) | LOCK_NB
, &tree_global_lock
, &tree_local_lock
);
5532 log_error_errno(r
, "Directory tree %s is currently busy.", arg_directory
);
5536 log_error_errno(r
, "Failed to lock %s: %m", arg_directory
);
5541 r
= chase_and_update(&arg_template
, 0);
5546 BLOCK_SIGNALS(SIGINT
);
5547 r
= btrfs_subvol_snapshot_at(AT_FDCWD
, arg_template
, AT_FDCWD
, arg_directory
,
5548 (arg_read_only
? BTRFS_SNAPSHOT_READ_ONLY
: 0) |
5549 BTRFS_SNAPSHOT_FALLBACK_COPY
|
5550 BTRFS_SNAPSHOT_FALLBACK_DIRECTORY
|
5551 BTRFS_SNAPSHOT_FALLBACK_IMMUTABLE
|
5552 BTRFS_SNAPSHOT_RECURSIVE
|
5553 BTRFS_SNAPSHOT_QUOTA
|
5554 BTRFS_SNAPSHOT_SIGINT
);
5557 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
,
5558 "Directory %s already exists, not populating from template %s.", arg_directory
, arg_template
);
5559 else if (r
== -EINTR
) {
5560 log_error_errno(r
, "Interrupted while copying file system tree to %s, removed again.", arg_directory
);
5563 log_error_errno(r
, "Couldn't create snapshot %s from %s: %m", arg_directory
, arg_template
);
5566 log_full(arg_quiet
? LOG_DEBUG
: LOG_INFO
,
5567 "Populated %s from template %s.", arg_directory
, arg_template
);
5571 if (arg_start_mode
== START_BOOT
) {
5572 _cleanup_free_
char *b
= NULL
;
5574 int check_os_release
, is_os_tree
;
5576 if (arg_pivot_root_new
) {
5577 b
= path_join(arg_directory
, arg_pivot_root_new
);
5587 check_os_release
= getenv_bool("SYSTEMD_NSPAWN_CHECK_OS_RELEASE");
5588 if (check_os_release
< 0 && check_os_release
!= -ENXIO
) {
5589 r
= log_error_errno(check_os_release
, "Failed to parse $SYSTEMD_NSPAWN_CHECK_OS_RELEASE: %m");
5593 is_os_tree
= path_is_os_tree(p
);
5594 if (is_os_tree
== 0 && check_os_release
== 0)
5595 log_debug("Directory %s is missing an os-release file, continuing anyway.", p
);
5596 else if (is_os_tree
<= 0) {
5597 r
= log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
5598 "Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", p
);
5602 _cleanup_free_
char *p
= NULL
;
5604 if (arg_pivot_root_new
)
5605 p
= path_join(arg_directory
, arg_pivot_root_new
, "/usr/");
5607 p
= path_join(arg_directory
, "/usr/");
5613 if (laccess(p
, F_OK
) < 0) {
5614 r
= log_error_errno(SYNTHETIC_ERRNO(EINVAL
),
5615 "Directory %s doesn't look like it has an OS tree (/usr/ directory is missing). Refusing.", arg_directory
);
5621 DissectImageFlags dissect_image_flags
=
5622 DISSECT_IMAGE_GENERIC_ROOT
|
5623 DISSECT_IMAGE_REQUIRE_ROOT
|
5624 DISSECT_IMAGE_RELAX_VAR_CHECK
|
5625 DISSECT_IMAGE_USR_NO_ROOT
|
5626 DISSECT_IMAGE_ADD_PARTITION_DEVICES
|
5627 DISSECT_IMAGE_PIN_PARTITION_DEVICES
;
5629 assert(!arg_template
);
5631 r
= chase_and_update(&arg_image
, 0);
5635 if (arg_ephemeral
) {
5636 _cleanup_free_
char *np
= NULL
;
5638 r
= tempfn_random(arg_image
, "machine.", &np
);
5640 log_error_errno(r
, "Failed to generate name for image snapshot: %m");
5644 /* Always take an exclusive lock on our own ephemeral copy. */
5645 r
= image_path_lock(np
, LOCK_EX
|LOCK_NB
, &tree_global_lock
, &tree_local_lock
);
5647 r
= log_error_errno(r
, "Failed to create image lock: %m");
5652 BLOCK_SIGNALS(SIGINT
);
5653 r
= copy_file_full(arg_image
, np
, O_EXCL
, arg_read_only
? 0400 : 0600,
5654 FS_NOCOW_FL
, FS_NOCOW_FL
,
5655 COPY_REFLINK
|COPY_CRTIME
|COPY_SIGINT
,
5659 log_error_errno(r
, "Interrupted while copying image file to %s, removed again.", np
);
5663 r
= log_error_errno(r
, "Failed to copy image file: %m");
5667 free_and_replace(arg_image
, np
);
5668 remove_image
= true;
5670 r
= image_path_lock(arg_image
, (arg_read_only
? LOCK_SH
: LOCK_EX
) | LOCK_NB
, &tree_global_lock
, &tree_local_lock
);
5672 r
= log_error_errno(r
, "Disk image %s is currently busy.", arg_image
);
5676 r
= log_error_errno(r
, "Failed to create image lock: %m");
5680 r
= verity_settings_load(
5681 &arg_verity_settings
,
5682 arg_image
, NULL
, NULL
);
5684 log_error_errno(r
, "Failed to read verity artefacts for %s: %m", arg_image
);
5688 if (arg_verity_settings
.data_path
)
5689 dissect_image_flags
|= DISSECT_IMAGE_NO_PARTITION_TABLE
;
5692 if (!mkdtemp(tmprootdir
)) {
5693 r
= log_error_errno(errno
, "Failed to create temporary directory: %m");
5697 remove_tmprootdir
= true;
5699 arg_directory
= strdup(tmprootdir
);
5700 if (!arg_directory
) {
5705 r
= loop_device_make_by_path(
5707 arg_read_only
? O_RDONLY
: O_RDWR
,
5708 /* sector_size= */ UINT32_MAX
,
5709 FLAGS_SET(dissect_image_flags
, DISSECT_IMAGE_NO_PARTITION_TABLE
) ? 0 : LO_FLAGS_PARTSCAN
,
5713 log_error_errno(r
, "Failed to set up loopback block device: %m");
5717 r
= dissect_loop_device_and_warn(
5719 &arg_verity_settings
,
5720 /* mount_options=*/ NULL
,
5721 arg_image_policy
?: &image_policy_container
,
5722 dissect_image_flags
,
5725 /* dissected_image_and_warn() already printed a brief error message. Extend on that with more details */
5726 log_notice("Note that the disk image needs to\n"
5727 " a) either contain only a single MBR partition of type 0x83 that is marked bootable\n"
5728 " b) or contain a single GPT partition of type 0FC63DAF-8483-4772-8E79-3D69D8477DE4\n"
5729 " c) or follow https://uapi-group.org/specifications/specs/discoverable_partitions_specification\n"
5730 " d) or contain a file system without a partition table\n"
5731 "in order to be bootable with systemd-nspawn.");
5737 r
= dissected_image_load_verity_sig_partition(
5740 &arg_verity_settings
);
5744 if (dissected_image
->has_verity
&& !arg_verity_settings
.root_hash
&& !dissected_image
->has_verity_sig
)
5745 log_notice("Note: image %s contains verity information, but no root hash specified and no embedded "
5746 "root hash signature found! Proceeding without integrity checking.", arg_image
);
5748 r
= dissected_image_decrypt_interactively(
5751 &arg_verity_settings
,
5756 /* Now that we mounted the image, let's try to remove it again, if it is ephemeral */
5757 if (remove_image
&& unlink(arg_image
) >= 0)
5758 remove_image
= false;
5760 if (arg_architecture
< 0)
5761 arg_architecture
= dissected_image_architecture(dissected_image
);
5764 r
= custom_mount_prepare_all(arg_directory
, arg_custom_mounts
, arg_n_custom_mounts
);
5768 if (arg_console_mode
< 0)
5770 isatty(STDIN_FILENO
) > 0 &&
5771 isatty(STDOUT_FILENO
) > 0 ? CONSOLE_INTERACTIVE
: CONSOLE_READ_ONLY
;
5773 if (arg_console_mode
== CONSOLE_PIPE
) /* if we pass STDERR on to the container, don't add our own logs into it too */
5777 log_info("Spawning container %s on %s.\nPress Ctrl-] three times within 1s to kill container.",
5778 arg_machine
, arg_image
?: arg_directory
);
5780 assert_se(sigprocmask_many(SIG_BLOCK
, NULL
, SIGCHLD
, SIGWINCH
, SIGTERM
, SIGINT
, SIGRTMIN
+18, -1) >= 0);
5782 r
= make_reaper_process(true);
5784 log_error_errno(r
, "Failed to become subreaper: %m");
5788 if (arg_expose_ports
) {
5789 r
= fw_ctx_new(&fw_ctx
);
5791 log_error_errno(r
, "Cannot expose configured ports, firewall initialization failed: %m");
5794 expose_args
.fw_ctx
= fw_ctx
;
5797 r
= run_container(dissected_image
,
5799 veth_name
, &veth_created
,
5800 &expose_args
, &master
,
5807 (void) sd_notify(false,
5808 r
== 0 && ret
== EXIT_FORCE_RESTART
? "STOPPING=1\nSTATUS=Restarting..." :
5809 "STOPPING=1\nSTATUS=Terminating...");
5812 (void) kill(pid
, SIGKILL
);
5814 /* Try to flush whatever is still queued in the pty */
5816 (void) copy_bytes(master
, STDOUT_FILENO
, UINT64_MAX
, 0);
5817 master
= safe_close(master
);
5821 (void) wait_for_terminate(pid
, NULL
);
5825 if (remove_directory
&& arg_directory
) {
5828 k
= rm_rf(arg_directory
, REMOVE_ROOT
|REMOVE_PHYSICAL
|REMOVE_SUBVOLUME
);
5830 log_warning_errno(k
, "Cannot remove '%s', ignoring: %m", arg_directory
);
5833 if (remove_image
&& arg_image
) {
5834 if (unlink(arg_image
) < 0)
5835 log_warning_errno(errno
, "Can't remove image file '%s', ignoring: %m", arg_image
);
5838 if (remove_tmprootdir
) {
5839 if (rmdir(tmprootdir
) < 0)
5840 log_debug_errno(errno
, "Can't remove temporary root directory '%s', ignoring: %m", tmprootdir
);
5846 p
= strjoina("/run/systemd/nspawn/propagate/", arg_machine
);
5847 (void) rm_rf(p
, REMOVE_ROOT
);
5850 expose_port_flush(&fw_ctx
, arg_expose_ports
, AF_INET
, &expose_args
.address4
);
5851 expose_port_flush(&fw_ctx
, arg_expose_ports
, AF_INET6
, &expose_args
.address6
);
5854 (void) remove_veth_links(veth_name
, arg_network_veth_extra
);
5855 (void) remove_bridge(arg_network_zone
);
5857 custom_mount_free_all(arg_custom_mounts
, arg_n_custom_mounts
);
5858 expose_port_free_all(arg_expose_ports
);
5859 rlimit_free_all(arg_rlimit
);
5860 device_node_array_free(arg_extra_nodes
, arg_n_extra_nodes
);
5861 machine_credential_free_all(arg_credentials
, arg_n_credentials
);
5869 DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run
);