1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
25 #include <sys/types.h>
26 #include <sys/syscall.h>
27 #include <sys/mount.h>
33 #include <sys/prctl.h>
34 #include <sys/capability.h>
37 #include <sys/signalfd.h>
41 #include <sys/socket.h>
42 #include <linux/netlink.h>
44 #include <linux/veth.h>
45 #include <sys/personality.h>
46 #include <linux/loop.h>
49 #include <selinux/selinux.h>
57 #include <blkid/blkid.h>
60 #include "sd-daemon.h"
70 #include "cgroup-util.h"
72 #include "path-util.h"
73 #include "loopback-setup.h"
74 #include "dev-setup.h"
79 #include "bus-error.h"
81 #include "bus-kernel.h"
84 #include "rtnl-util.h"
85 #include "udev-util.h"
86 #include "blkid-util.h"
88 #include "siphash24.h"
90 #include "base-filesystem.h"
92 #include "event-util.h"
95 #include "seccomp-util.h"
98 typedef enum ContainerStatus {
103 typedef enum LinkJournal {
110 typedef enum Volatile {
116 static char *arg_directory = NULL;
117 static char *arg_user = NULL;
118 static sd_id128_t arg_uuid = {};
119 static char *arg_machine = NULL;
120 static const char *arg_selinux_context = NULL;
121 static const char *arg_selinux_apifs_context = NULL;
122 static const char *arg_slice = NULL;
123 static bool arg_private_network = false;
124 static bool arg_read_only = false;
125 static bool arg_boot = false;
126 static LinkJournal arg_link_journal = LINK_AUTO;
127 static bool arg_link_journal_try = false;
128 static uint64_t arg_retain =
129 (1ULL << CAP_CHOWN) |
130 (1ULL << CAP_DAC_OVERRIDE) |
131 (1ULL << CAP_DAC_READ_SEARCH) |
132 (1ULL << CAP_FOWNER) |
133 (1ULL << CAP_FSETID) |
134 (1ULL << CAP_IPC_OWNER) |
136 (1ULL << CAP_LEASE) |
137 (1ULL << CAP_LINUX_IMMUTABLE) |
138 (1ULL << CAP_NET_BIND_SERVICE) |
139 (1ULL << CAP_NET_BROADCAST) |
140 (1ULL << CAP_NET_RAW) |
141 (1ULL << CAP_SETGID) |
142 (1ULL << CAP_SETFCAP) |
143 (1ULL << CAP_SETPCAP) |
144 (1ULL << CAP_SETUID) |
145 (1ULL << CAP_SYS_ADMIN) |
146 (1ULL << CAP_SYS_CHROOT) |
147 (1ULL << CAP_SYS_NICE) |
148 (1ULL << CAP_SYS_PTRACE) |
149 (1ULL << CAP_SYS_TTY_CONFIG) |
150 (1ULL << CAP_SYS_RESOURCE) |
151 (1ULL << CAP_SYS_BOOT) |
152 (1ULL << CAP_AUDIT_WRITE) |
153 (1ULL << CAP_AUDIT_CONTROL) |
155 static char **arg_bind = NULL;
156 static char **arg_bind_ro = NULL;
157 static char **arg_tmpfs = NULL;
158 static char **arg_setenv = NULL;
159 static bool arg_quiet = false;
160 static bool arg_share_system = false;
161 static bool arg_register = true;
162 static bool arg_keep_unit = false;
163 static char **arg_network_interfaces = NULL;
164 static char **arg_network_macvlan = NULL;
165 static bool arg_network_veth = false;
166 static const char *arg_network_bridge = NULL;
167 static unsigned long arg_personality = 0xffffffffLU;
168 static const char *arg_image = NULL;
169 static Volatile arg_volatile = VOLATILE_NO;
171 static void help(void) {
172 printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
173 "Spawn a minimal namespace container for debugging, testing and building.\n\n"
174 " -h --help Show this help\n"
175 " --version Print version string\n"
176 " -q --quiet Do not show status information\n"
177 " -D --directory=PATH Root directory for the container\n"
178 " -i --image=PATH File system device or image for the container\n"
179 " -b --boot Boot up full system (i.e. invoke init)\n"
180 " -u --user=USER Run the command under specified user or uid\n"
181 " -M --machine=NAME Set the machine name for the container\n"
182 " --uuid=UUID Set a specific machine UUID for the container\n"
183 " -S --slice=SLICE Place the container in the specified slice\n"
184 " --private-network Disable network in container\n"
185 " --network-interface=INTERFACE\n"
186 " Assign an existing network interface to the\n"
188 " --network-macvlan=INTERFACE\n"
189 " Create a macvlan network interface based on an\n"
190 " existing network interface to the container\n"
191 " --network-veth Add a virtual ethernet connection between host\n"
193 " --network-bridge=INTERFACE\n"
194 " Add a virtual ethernet connection between host\n"
195 " and container and add it to an existing bridge on\n"
197 " -Z --selinux-context=SECLABEL\n"
198 " Set the SELinux security context to be used by\n"
199 " processes in the container\n"
200 " -L --selinux-apifs-context=SECLABEL\n"
201 " Set the SELinux security context to be used by\n"
202 " API/tmpfs file systems in the container\n"
203 " --capability=CAP In addition to the default, retain specified\n"
205 " --drop-capability=CAP Drop the specified capability from the default set\n"
206 " --link-journal=MODE Link up guest journal, one of no, auto, guest, host,\n"
207 " try-guest, try-host\n"
208 " -j Equivalent to --link-journal=try-guest\n"
209 " --read-only Mount the root directory read-only\n"
210 " --bind=PATH[:PATH] Bind mount a file or directory from the host into\n"
212 " --bind-ro=PATH[:PATH] Similar, but creates a read-only bind mount\n"
213 " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n"
214 " --setenv=NAME=VALUE Pass an environment variable to PID 1\n"
215 " --share-system Share system namespaces with host\n"
216 " --register=BOOLEAN Register container as machine\n"
217 " --keep-unit Do not register a scope for the machine, reuse\n"
218 " the service unit nspawn is running in\n"
219 " --volatile[=MODE] Run the system in volatile mode\n",
220 program_invocation_short_name);
223 static int parse_argv(int argc, char *argv[]) {
240 ARG_NETWORK_INTERFACE,
248 static const struct option options[] = {
249 { "help", no_argument, NULL, 'h' },
250 { "version", no_argument, NULL, ARG_VERSION },
251 { "directory", required_argument, NULL, 'D' },
252 { "user", required_argument, NULL, 'u' },
253 { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK },
254 { "boot", no_argument, NULL, 'b' },
255 { "uuid", required_argument, NULL, ARG_UUID },
256 { "read-only", no_argument, NULL, ARG_READ_ONLY },
257 { "capability", required_argument, NULL, ARG_CAPABILITY },
258 { "drop-capability", required_argument, NULL, ARG_DROP_CAPABILITY },
259 { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
260 { "bind", required_argument, NULL, ARG_BIND },
261 { "bind-ro", required_argument, NULL, ARG_BIND_RO },
262 { "tmpfs", required_argument, NULL, ARG_TMPFS },
263 { "machine", required_argument, NULL, 'M' },
264 { "slice", required_argument, NULL, 'S' },
265 { "setenv", required_argument, NULL, ARG_SETENV },
266 { "selinux-context", required_argument, NULL, 'Z' },
267 { "selinux-apifs-context", required_argument, NULL, 'L' },
268 { "quiet", no_argument, NULL, 'q' },
269 { "share-system", no_argument, NULL, ARG_SHARE_SYSTEM },
270 { "register", required_argument, NULL, ARG_REGISTER },
271 { "keep-unit", no_argument, NULL, ARG_KEEP_UNIT },
272 { "network-interface", required_argument, NULL, ARG_NETWORK_INTERFACE },
273 { "network-macvlan", required_argument, NULL, ARG_NETWORK_MACVLAN },
274 { "network-veth", no_argument, NULL, ARG_NETWORK_VETH },
275 { "network-bridge", required_argument, NULL, ARG_NETWORK_BRIDGE },
276 { "personality", required_argument, NULL, ARG_PERSONALITY },
277 { "image", required_argument, NULL, 'i' },
278 { "volatile", optional_argument, NULL, ARG_VOLATILE },
283 uint64_t plus = 0, minus = 0;
288 while ((c = getopt_long(argc, argv, "+hD:u:bL:M:jS:Z:qi:", options, NULL)) >= 0)
297 puts(PACKAGE_STRING);
298 puts(SYSTEMD_FEATURES);
303 arg_directory = canonicalize_file_name(optarg);
304 if (!arg_directory) {
305 log_error_errno(errno, "Invalid root directory: %m");
317 arg_user = strdup(optarg);
323 case ARG_NETWORK_BRIDGE:
324 arg_network_bridge = optarg;
328 case ARG_NETWORK_VETH:
329 arg_network_veth = true;
330 arg_private_network = true;
333 case ARG_NETWORK_INTERFACE:
334 if (strv_extend(&arg_network_interfaces, optarg) < 0)
337 arg_private_network = true;
340 case ARG_NETWORK_MACVLAN:
341 if (strv_extend(&arg_network_macvlan, optarg) < 0)
346 case ARG_PRIVATE_NETWORK:
347 arg_private_network = true;
355 r = sd_id128_from_string(optarg, &arg_uuid);
357 log_error("Invalid UUID: %s", optarg);
367 if (isempty(optarg)) {
372 if (!hostname_is_valid(optarg)) {
373 log_error("Invalid machine name: %s", optarg);
378 arg_machine = strdup(optarg);
386 arg_selinux_context = optarg;
390 arg_selinux_apifs_context = optarg;
394 arg_read_only = true;
398 case ARG_DROP_CAPABILITY: {
399 const char *state, *word;
402 FOREACH_WORD_SEPARATOR(word, length, optarg, ",", state) {
403 _cleanup_free_ char *t;
406 t = strndup(word, length);
410 if (streq(t, "all")) {
411 if (c == ARG_CAPABILITY)
412 plus = (uint64_t) -1;
414 minus = (uint64_t) -1;
416 if (cap_from_name(t, &cap) < 0) {
417 log_error("Failed to parse capability %s.", t);
421 if (c == ARG_CAPABILITY)
422 plus |= 1ULL << (uint64_t) cap;
424 minus |= 1ULL << (uint64_t) cap;
432 arg_link_journal = LINK_GUEST;
433 arg_link_journal_try = true;
436 case ARG_LINK_JOURNAL:
437 if (streq(optarg, "auto"))
438 arg_link_journal = LINK_AUTO;
439 else if (streq(optarg, "no"))
440 arg_link_journal = LINK_NO;
441 else if (streq(optarg, "guest"))
442 arg_link_journal = LINK_GUEST;
443 else if (streq(optarg, "host"))
444 arg_link_journal = LINK_HOST;
445 else if (streq(optarg, "try-guest")) {
446 arg_link_journal = LINK_GUEST;
447 arg_link_journal_try = true;
448 } else if (streq(optarg, "try-host")) {
449 arg_link_journal = LINK_HOST;
450 arg_link_journal_try = true;
452 log_error("Failed to parse link journal mode %s", optarg);
460 _cleanup_free_ char *a = NULL, *b = NULL;
464 x = c == ARG_BIND ? &arg_bind : &arg_bind_ro;
466 e = strchr(optarg, ':');
468 a = strndup(optarg, e - optarg);
478 if (!path_is_absolute(a) || !path_is_absolute(b)) {
479 log_error("Invalid bind mount specification: %s", optarg);
483 r = strv_extend(x, a);
487 r = strv_extend(x, b);
495 _cleanup_free_ char *a = NULL, *b = NULL;
498 e = strchr(optarg, ':');
500 a = strndup(optarg, e - optarg);
504 b = strdup("mode=0755");
510 if (!path_is_absolute(a)) {
511 log_error("Invalid tmpfs specification: %s", optarg);
515 r = strv_push(&arg_tmpfs, a);
521 r = strv_push(&arg_tmpfs, b);
533 if (!env_assignment_is_valid(optarg)) {
534 log_error("Environment variable assignment '%s' is not valid.", optarg);
538 n = strv_env_set(arg_setenv, optarg);
542 strv_free(arg_setenv);
551 case ARG_SHARE_SYSTEM:
552 arg_share_system = true;
556 r = parse_boolean(optarg);
558 log_error("Failed to parse --register= argument: %s", optarg);
566 arg_keep_unit = true;
569 case ARG_PERSONALITY:
571 arg_personality = personality_from_string(optarg);
572 if (arg_personality == 0xffffffffLU) {
573 log_error("Unknown or unsupported personality '%s'.", optarg);
582 arg_volatile = VOLATILE_YES;
584 r = parse_boolean(optarg);
586 if (streq(optarg, "state"))
587 arg_volatile = VOLATILE_STATE;
589 log_error("Failed to parse --volatile= argument: %s", optarg);
593 arg_volatile = r ? VOLATILE_YES : VOLATILE_NO;
602 assert_not_reached("Unhandled option");
605 if (arg_share_system)
606 arg_register = false;
608 if (arg_boot && arg_share_system) {
609 log_error("--boot and --share-system may not be combined.");
613 if (arg_keep_unit && cg_pid_get_owner_uid(0, NULL) >= 0) {
614 log_error("--keep-unit may not be used when invoked from a user session.");
618 if (arg_directory && arg_image) {
619 log_error("--directory= and --image= may not be combined.");
623 if (arg_volatile != VOLATILE_NO && arg_read_only) {
624 log_error("Cannot combine --read-only with --volatile. Note that --volatile already implies a read-only base hierarchy.");
628 arg_retain = (arg_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus;
633 static int mount_all(const char *dest) {
635 typedef struct MountPoint {
644 static const MountPoint mount_table[] = {
645 { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
646 { "/proc/sys", "/proc/sys", NULL, NULL, MS_BIND, true }, /* Bind mount first */
647 { NULL, "/proc/sys", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, true }, /* Then, make it r/o */
648 { "sysfs", "/sys", "sysfs", NULL, MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
649 { "tmpfs", "/dev", "tmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true },
650 { "devpts", "/dev/pts", "devpts","newinstance,ptmxmode=0666,mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, true },
651 { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
652 { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
654 { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL, MS_BIND, false }, /* Bind mount first */
655 { NULL, "/sys/fs/selinux", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, false }, /* Then, make it r/o */
662 for (k = 0; k < ELEMENTSOF(mount_table); k++) {
663 _cleanup_free_ char *where = NULL;
665 _cleanup_free_ char *options = NULL;
670 where = strjoin(dest, "/", mount_table[k].where, NULL);
674 t = path_is_mount_point(where, true);
676 log_error_errno(t, "Failed to detect whether %s is a mount point: %m", where);
684 /* Skip this entry if it is not a remount. */
685 if (mount_table[k].what && t > 0)
688 t = mkdir_p(where, 0755);
690 if (mount_table[k].fatal) {
691 log_error_errno(t, "Failed to create directory %s: %m", where);
696 log_warning_errno(t, "Failed to create directory %s: %m", where);
702 if (arg_selinux_apifs_context &&
703 (streq_ptr(mount_table[k].what, "tmpfs") || streq_ptr(mount_table[k].what, "devpts"))) {
704 options = strjoin(mount_table[k].options, ",context=\"", arg_selinux_apifs_context, "\"", NULL);
711 o = mount_table[k].options;
714 if (mount(mount_table[k].what,
717 mount_table[k].flags,
720 if (mount_table[k].fatal) {
721 log_error_errno(errno, "mount(%s) failed: %m", where);
726 log_warning_errno(errno, "mount(%s) failed: %m", where);
733 static int mount_binds(const char *dest, char **l, bool ro) {
736 STRV_FOREACH_PAIR(x, y, l) {
737 _cleanup_free_ char *where = NULL;
738 struct stat source_st, dest_st;
741 if (stat(*x, &source_st) < 0)
742 return log_error_errno(errno, "Failed to stat %s: %m", *x);
744 where = strappend(dest, *y);
748 r = stat(where, &dest_st);
750 if ((source_st.st_mode & S_IFMT) != (dest_st.st_mode & S_IFMT)) {
751 log_error("The file types of %s and %s do not match. Refusing bind mount", *x, where);
754 } else if (errno == ENOENT) {
755 r = mkdir_parents_label(where, 0755);
757 return log_error_errno(r, "Failed to bind mount %s: %m", *x);
759 log_error_errno(errno, "Failed to bind mount %s: %m", *x);
763 /* Create the mount point, but be conservative -- refuse to create block
764 * and char devices. */
765 if (S_ISDIR(source_st.st_mode)) {
766 r = mkdir_label(where, 0755);
767 if (r < 0 && errno != EEXIST)
768 return log_error_errno(r, "Failed to create mount point %s: %m", where);
769 } else if (S_ISFIFO(source_st.st_mode)) {
770 r = mkfifo(where, 0644);
771 if (r < 0 && errno != EEXIST)
772 return log_error_errno(errno, "Failed to create mount point %s: %m", where);
773 } else if (S_ISSOCK(source_st.st_mode)) {
774 r = mknod(where, 0644 | S_IFSOCK, 0);
775 if (r < 0 && errno != EEXIST)
776 return log_error_errno(errno, "Failed to create mount point %s: %m", where);
777 } else if (S_ISREG(source_st.st_mode)) {
780 return log_error_errno(r, "Failed to create mount point %s: %m", where);
782 log_error("Refusing to create mountpoint for file: %s", *x);
786 if (mount(*x, where, "bind", MS_BIND, NULL) < 0)
787 return log_error_errno(errno, "mount(%s) failed: %m", where);
790 r = bind_remount_recursive(where, true);
792 return log_error_errno(r, "Read-Only bind mount failed: %m");
799 static int mount_tmpfs(const char *dest) {
802 STRV_FOREACH_PAIR(i, o, arg_tmpfs) {
803 _cleanup_free_ char *where = NULL;
806 where = strappend(dest, *i);
810 r = mkdir_label(where, 0755);
811 if (r < 0 && r != -EEXIST)
812 return log_error_errno(r, "Creating mount point for tmpfs %s failed: %m", where);
814 if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, *o) < 0)
815 return log_error_errno(errno, "tmpfs mount to %s failed: %m", where);
821 static int setup_timezone(const char *dest) {
822 _cleanup_free_ char *where = NULL, *p = NULL, *q = NULL, *check = NULL, *what = NULL;
828 /* Fix the timezone, if possible */
829 r = readlink_malloc("/etc/localtime", &p);
831 log_warning("/etc/localtime is not a symlink, not updating container timezone.");
835 z = path_startswith(p, "../usr/share/zoneinfo/");
837 z = path_startswith(p, "/usr/share/zoneinfo/");
839 log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone.");
843 where = strappend(dest, "/etc/localtime");
847 r = readlink_malloc(where, &q);
849 y = path_startswith(q, "../usr/share/zoneinfo/");
851 y = path_startswith(q, "/usr/share/zoneinfo/");
853 /* Already pointing to the right place? Then do nothing .. */
854 if (y && streq(y, z))
858 check = strjoin(dest, "/usr/share/zoneinfo/", z, NULL);
862 if (access(check, F_OK) < 0) {
863 log_warning("Timezone %s does not exist in container, not updating container timezone.", z);
867 what = strappend("../usr/share/zoneinfo/", z);
871 r = mkdir_parents(where, 0755);
873 log_error_errno(r, "Failed to create directory for timezone info %s in container: %m", where);
879 if (r < 0 && errno != ENOENT) {
880 log_error_errno(errno, "Failed to remove existing timezone info %s in container: %m", where);
885 if (symlink(what, where) < 0) {
886 log_error_errno(errno, "Failed to correct timezone of container: %m");
893 static int setup_resolv_conf(const char *dest) {
894 _cleanup_free_ char *where = NULL;
899 if (arg_private_network)
902 /* Fix resolv.conf, if possible */
903 where = strappend(dest, "/etc/resolv.conf");
907 /* We don't really care for the results of this really. If it
908 * fails, it fails, but meh... */
909 r = mkdir_parents(where, 0755);
911 log_warning_errno(r, "Failed to create parent directory for resolv.conf %s: %m", where);
916 r = copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW, 0644);
918 log_warning_errno(r, "Failed to copy /etc/resolv.conf to %s: %m", where);
926 static int setup_volatile_state(const char *directory) {
932 if (arg_volatile != VOLATILE_STATE)
935 /* --volatile=state means we simply overmount /var
936 with a tmpfs, and the rest read-only. */
938 r = bind_remount_recursive(directory, true);
940 return log_error_errno(r, "Failed to remount %s read-only: %m", directory);
942 p = strappenda(directory, "/var");
944 if (r < 0 && errno != EEXIST)
945 return log_error_errno(errno, "Failed to create %s: %m", directory);
947 if (mount("tmpfs", p, "tmpfs", MS_STRICTATIME, "mode=755") < 0)
948 return log_error_errno(errno, "Failed to mount tmpfs to /var: %m");
953 static int setup_volatile(const char *directory) {
954 bool tmpfs_mounted = false, bind_mounted = false;
955 char template[] = "/tmp/nspawn-volatile-XXXXXX";
961 if (arg_volatile != VOLATILE_YES)
964 /* --volatile=yes means we mount a tmpfs to the root dir, and
965 the original /usr to use inside it, and that read-only. */
967 if (!mkdtemp(template))
968 return log_error_errno(errno, "Failed to create temporary directory: %m");
970 if (mount("tmpfs", template, "tmpfs", MS_STRICTATIME, "mode=755") < 0) {
971 log_error_errno(errno, "Failed to mount tmpfs for root directory: %m");
976 tmpfs_mounted = true;
978 f = strappenda(directory, "/usr");
979 t = strappenda(template, "/usr");
982 if (r < 0 && errno != EEXIST) {
983 log_error_errno(errno, "Failed to create %s: %m", t);
988 if (mount(f, t, "bind", MS_BIND|MS_REC, NULL) < 0) {
989 log_error_errno(errno, "Failed to create /usr bind mount: %m");
996 r = bind_remount_recursive(t, true);
998 log_error_errno(r, "Failed to remount %s read-only: %m", t);
1002 if (mount(template, directory, NULL, MS_MOVE, NULL) < 0) {
1003 log_error_errno(errno, "Failed to move root mount: %m");
1021 static char* id128_format_as_uuid(sd_id128_t id, char s[37]) {
1024 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
1025 SD_ID128_FORMAT_VAL(id));
1030 static int setup_boot_id(const char *dest) {
1031 _cleanup_free_ char *from = NULL, *to = NULL;
1032 sd_id128_t rnd = {};
1038 if (arg_share_system)
1041 /* Generate a new randomized boot ID, so that each boot-up of
1042 * the container gets a new one */
1044 from = strappend(dest, "/dev/proc-sys-kernel-random-boot-id");
1045 to = strappend(dest, "/proc/sys/kernel/random/boot_id");
1049 r = sd_id128_randomize(&rnd);
1051 return log_error_errno(r, "Failed to generate random boot id: %m");
1053 id128_format_as_uuid(rnd, as_uuid);
1055 r = write_string_file(from, as_uuid);
1057 return log_error_errno(r, "Failed to write boot id: %m");
1059 if (mount(from, to, "bind", MS_BIND, NULL) < 0) {
1060 log_error_errno(errno, "Failed to bind mount boot id: %m");
1062 } else if (mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL))
1063 log_warning_errno(errno, "Failed to make boot id read-only: %m");
1069 static int copy_devnodes(const char *dest) {
1071 static const char devnodes[] =
1082 _cleanup_umask_ mode_t u;
1088 NULSTR_FOREACH(d, devnodes) {
1089 _cleanup_free_ char *from = NULL, *to = NULL;
1092 from = strappend("/dev/", d);
1093 to = strjoin(dest, "/dev/", d, NULL);
1097 if (stat(from, &st) < 0) {
1099 if (errno != ENOENT)
1100 return log_error_errno(errno, "Failed to stat %s: %m", from);
1102 } else if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
1104 log_error("%s is not a char or block device, cannot copy", from);
1108 r = mkdir_parents(to, 0775);
1110 log_error_errno(r, "Failed to create parent directory of %s: %m", to);
1114 if (mknod(to, st.st_mode, st.st_rdev) < 0)
1115 return log_error_errno(errno, "mknod(%s) failed: %m", dest);
1122 static int setup_ptmx(const char *dest) {
1123 _cleanup_free_ char *p = NULL;
1125 p = strappend(dest, "/dev/ptmx");
1129 if (symlink("pts/ptmx", p) < 0)
1130 return log_error_errno(errno, "Failed to create /dev/ptmx symlink: %m");
1135 static int setup_dev_console(const char *dest, const char *console) {
1136 _cleanup_umask_ mode_t u;
1146 if (stat("/dev/null", &st) < 0)
1147 return log_error_errno(errno, "Failed to stat /dev/null: %m");
1149 r = chmod_and_chown(console, 0600, 0, 0);
1151 return log_error_errno(r, "Failed to correct access mode for TTY: %m");
1153 /* We need to bind mount the right tty to /dev/console since
1154 * ptys can only exist on pts file systems. To have something
1155 * to bind mount things on we create a device node first, and
1156 * use /dev/null for that since we the cgroups device policy
1157 * allows us to create that freely, while we cannot create
1158 * /dev/console. (Note that the major minor doesn't actually
1159 * matter here, since we mount it over anyway). */
1161 to = strappenda(dest, "/dev/console");
1162 if (mknod(to, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0)
1163 return log_error_errno(errno, "mknod() for /dev/console failed: %m");
1165 if (mount(console, to, "bind", MS_BIND, NULL) < 0)
1166 return log_error_errno(errno, "Bind mount for /dev/console failed: %m");
1171 static int setup_kmsg(const char *dest, int kmsg_socket) {
1172 _cleanup_free_ char *from = NULL, *to = NULL;
1174 _cleanup_umask_ mode_t u;
1176 struct cmsghdr cmsghdr;
1177 uint8_t buf[CMSG_SPACE(sizeof(int))];
1179 struct msghdr mh = {
1180 .msg_control = &control,
1181 .msg_controllen = sizeof(control),
1183 struct cmsghdr *cmsg;
1186 assert(kmsg_socket >= 0);
1190 /* We create the kmsg FIFO as /dev/kmsg, but immediately
1191 * delete it after bind mounting it to /proc/kmsg. While FIFOs
1192 * on the reading side behave very similar to /proc/kmsg,
1193 * their writing side behaves differently from /dev/kmsg in
1194 * that writing blocks when nothing is reading. In order to
1195 * avoid any problems with containers deadlocking due to this
1196 * we simply make /dev/kmsg unavailable to the container. */
1197 if (asprintf(&from, "%s/dev/kmsg", dest) < 0 ||
1198 asprintf(&to, "%s/proc/kmsg", dest) < 0)
1201 if (mkfifo(from, 0600) < 0)
1202 return log_error_errno(errno, "mkfifo() for /dev/kmsg failed: %m");
1204 r = chmod_and_chown(from, 0600, 0, 0);
1206 return log_error_errno(r, "Failed to correct access mode for /dev/kmsg: %m");
1208 if (mount(from, to, "bind", MS_BIND, NULL) < 0)
1209 return log_error_errno(errno, "Bind mount for /proc/kmsg failed: %m");
1211 fd = open(from, O_RDWR|O_NDELAY|O_CLOEXEC);
1213 return log_error_errno(errno, "Failed to open fifo: %m");
1215 cmsg = CMSG_FIRSTHDR(&mh);
1216 cmsg->cmsg_level = SOL_SOCKET;
1217 cmsg->cmsg_type = SCM_RIGHTS;
1218 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
1219 memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
1221 mh.msg_controllen = cmsg->cmsg_len;
1223 /* Store away the fd in the socket, so that it stays open as
1224 * long as we run the child */
1225 k = sendmsg(kmsg_socket, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
1229 return log_error_errno(errno, "Failed to send FIFO fd: %m");
1231 /* And now make the FIFO unavailable as /dev/kmsg... */
1236 static int setup_hostname(void) {
1238 if (arg_share_system)
1241 if (sethostname_idempotent(arg_machine) < 0)
1247 static int setup_journal(const char *directory) {
1248 sd_id128_t machine_id, this_id;
1249 _cleanup_free_ char *p = NULL, *b = NULL, *q = NULL, *d = NULL;
1253 p = strappend(directory, "/etc/machine-id");
1257 r = read_one_line_file(p, &b);
1258 if (r == -ENOENT && arg_link_journal == LINK_AUTO)
1261 return log_error_errno(r, "Failed to read machine ID from %s: %m", p);
1264 if (isempty(id) && arg_link_journal == LINK_AUTO)
1267 /* Verify validity */
1268 r = sd_id128_from_string(id, &machine_id);
1270 return log_error_errno(r, "Failed to parse machine ID from %s: %m", p);
1272 r = sd_id128_get_machine(&this_id);
1274 return log_error_errno(r, "Failed to retrieve machine ID: %m");
1276 if (sd_id128_equal(machine_id, this_id)) {
1277 log_full(arg_link_journal == LINK_AUTO ? LOG_WARNING : LOG_ERR,
1278 "Host and machine ids are equal (%s): refusing to link journals", id);
1279 if (arg_link_journal == LINK_AUTO)
1285 if (arg_link_journal == LINK_NO)
1289 p = strappend("/var/log/journal/", id);
1290 q = strjoin(directory, "/var/log/journal/", id, NULL);
1294 if (path_is_mount_point(p, false) > 0) {
1295 if (arg_link_journal != LINK_AUTO) {
1296 log_error("%s: already a mount point, refusing to use for journal", p);
1303 if (path_is_mount_point(q, false) > 0) {
1304 if (arg_link_journal != LINK_AUTO) {
1305 log_error("%s: already a mount point, refusing to use for journal", q);
1312 r = readlink_and_make_absolute(p, &d);
1314 if ((arg_link_journal == LINK_GUEST ||
1315 arg_link_journal == LINK_AUTO) &&
1318 r = mkdir_p(q, 0755);
1320 log_warning_errno(errno, "Failed to create directory %s: %m", q);
1325 return log_error_errno(errno, "Failed to remove symlink %s: %m", p);
1326 } else if (r == -EINVAL) {
1328 if (arg_link_journal == LINK_GUEST &&
1331 if (errno == ENOTDIR) {
1332 log_error("%s already exists and is neither a symlink nor a directory", p);
1335 log_error_errno(errno, "Failed to remove %s: %m", p);
1339 } else if (r != -ENOENT) {
1340 log_error_errno(errno, "readlink(%s) failed: %m", p);
1344 if (arg_link_journal == LINK_GUEST) {
1346 if (symlink(q, p) < 0) {
1347 if (arg_link_journal_try) {
1348 log_debug_errno(errno, "Failed to symlink %s to %s, skipping journal setup: %m", q, p);
1351 log_error_errno(errno, "Failed to symlink %s to %s: %m", q, p);
1356 r = mkdir_p(q, 0755);
1358 log_warning_errno(errno, "Failed to create directory %s: %m", q);
1362 if (arg_link_journal == LINK_HOST) {
1363 /* don't create parents here -- if the host doesn't have
1364 * permanent journal set up, don't force it here */
1367 if (arg_link_journal_try) {
1368 log_debug_errno(errno, "Failed to create %s, skipping journal setup: %m", p);
1371 log_error_errno(errno, "Failed to create %s: %m", p);
1376 } else if (access(p, F_OK) < 0)
1379 if (dir_is_empty(q) == 0)
1380 log_warning("%s is not empty, proceeding anyway.", q);
1382 r = mkdir_p(q, 0755);
1384 log_error_errno(errno, "Failed to create %s: %m", q);
1388 if (mount(p, q, "bind", MS_BIND, NULL) < 0)
1389 return log_error_errno(errno, "Failed to bind mount journal from host into guest: %m");
1394 static int drop_capabilities(void) {
1395 return capability_bounding_set_drop(~arg_retain, false);
1398 static int register_machine(pid_t pid, int local_ifindex) {
1399 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
1400 _cleanup_bus_close_unref_ sd_bus *bus = NULL;
1406 r = sd_bus_default_system(&bus);
1408 return log_error_errno(r, "Failed to open system bus: %m");
1410 if (arg_keep_unit) {
1411 r = sd_bus_call_method(
1413 "org.freedesktop.machine1",
1414 "/org/freedesktop/machine1",
1415 "org.freedesktop.machine1.Manager",
1416 "RegisterMachineWithNetwork",
1421 SD_BUS_MESSAGE_APPEND_ID128(arg_uuid),
1425 strempty(arg_directory),
1426 local_ifindex > 0 ? 1 : 0, local_ifindex);
1428 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
1430 r = sd_bus_message_new_method_call(
1433 "org.freedesktop.machine1",
1434 "/org/freedesktop/machine1",
1435 "org.freedesktop.machine1.Manager",
1436 "CreateMachineWithNetwork");
1438 return log_error_errno(r, "Failed to create message: %m");
1440 r = sd_bus_message_append(
1444 SD_BUS_MESSAGE_APPEND_ID128(arg_uuid),
1448 strempty(arg_directory),
1449 local_ifindex > 0 ? 1 : 0, local_ifindex);
1451 return log_error_errno(r, "Failed to append message arguments: %m");
1453 r = sd_bus_message_open_container(m, 'a', "(sv)");
1455 return log_error_errno(r, "Failed to open container: %m");
1457 if (!isempty(arg_slice)) {
1458 r = sd_bus_message_append(m, "(sv)", "Slice", "s", arg_slice);
1460 return log_error_errno(r, "Failed to append slice: %m");
1463 r = sd_bus_message_append(m, "(sv)", "DevicePolicy", "s", "strict");
1465 return log_error_errno(r, "Failed to add device policy: %m");
1467 r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 9,
1468 /* Allow the container to
1469 * access and create the API
1470 * device nodes, so that
1471 * PrivateDevices= in the
1472 * container can work
1477 "/dev/random", "rwm",
1478 "/dev/urandom", "rwm",
1480 "/dev/net/tun", "rwm",
1481 /* Allow the container
1482 * access to ptys. However,
1484 * container to ever create
1485 * these device nodes. */
1486 "/dev/pts/ptmx", "rw",
1489 return log_error_errno(r, "Failed to add device whitelist: %m");
1491 r = sd_bus_message_close_container(m);
1493 return log_error_errno(r, "Failed to close container: %m");
1495 r = sd_bus_call(bus, m, 0, &error, NULL);
1499 log_error("Failed to register machine: %s", bus_error_message(&error, r));
1506 static int terminate_machine(pid_t pid) {
1507 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
1508 _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
1509 _cleanup_bus_close_unref_ sd_bus *bus = NULL;
1516 r = sd_bus_default_system(&bus);
1518 return log_error_errno(r, "Failed to open system bus: %m");
1520 r = sd_bus_call_method(
1522 "org.freedesktop.machine1",
1523 "/org/freedesktop/machine1",
1524 "org.freedesktop.machine1.Manager",
1531 /* Note that the machine might already have been
1532 * cleaned up automatically, hence don't consider it a
1533 * failure if we cannot get the machine object. */
1534 log_debug("Failed to get machine: %s", bus_error_message(&error, r));
1538 r = sd_bus_message_read(reply, "o", &path);
1540 return bus_log_parse_error(r);
1542 r = sd_bus_call_method(
1544 "org.freedesktop.machine1",
1546 "org.freedesktop.machine1.Machine",
1552 log_debug("Failed to terminate machine: %s", bus_error_message(&error, r));
1559 static int reset_audit_loginuid(void) {
1560 _cleanup_free_ char *p = NULL;
1563 if (arg_share_system)
1566 r = read_one_line_file("/proc/self/loginuid", &p);
1570 return log_error_errno(r, "Failed to read /proc/self/loginuid: %m");
1572 /* Already reset? */
1573 if (streq(p, "4294967295"))
1576 r = write_string_file("/proc/self/loginuid", "4294967295");
1578 log_error("Failed to reset audit login UID. This probably means that your kernel is too\n"
1579 "old and you have audit enabled. Note that the auditing subsystem is known to\n"
1580 "be incompatible with containers on old kernels. Please make sure to upgrade\n"
1581 "your kernel or to off auditing with 'audit=0' on the kernel command line before\n"
1582 "using systemd-nspawn. Sleeping for 5s... (%s)\n", strerror(-r));
1590 #define HOST_HASH_KEY SD_ID128_MAKE(1a,37,6f,c7,46,ec,45,0b,ad,a3,d5,31,06,60,5d,b1)
1591 #define CONTAINER_HASH_KEY SD_ID128_MAKE(c3,c4,f9,19,b5,57,b2,1c,e6,cf,14,27,03,9c,ee,a2)
1592 #define MACVLAN_HASH_KEY SD_ID128_MAKE(00,13,6d,bc,66,83,44,81,bb,0c,f9,51,1f,24,a6,6f)
1594 static int generate_mac(struct ether_addr *mac, sd_id128_t hash_key, unsigned idx) {
1601 l = strlen(arg_machine);
1602 sz = sizeof(sd_id128_t) + l;
1607 /* fetch some persistent data unique to the host */
1608 r = sd_id128_get_machine((sd_id128_t*) v);
1612 /* combine with some data unique (on this host) to this
1613 * container instance */
1614 memcpy(mempcpy(v + sizeof(sd_id128_t), arg_machine, l), &idx, sizeof(idx));
1616 /* Let's hash the host machine ID plus the container name. We
1617 * use a fixed, but originally randomly created hash key here. */
1618 siphash24(result, v, sz, hash_key.bytes);
1620 assert_cc(ETH_ALEN <= sizeof(result));
1621 memcpy(mac->ether_addr_octet, result, ETH_ALEN);
1623 /* see eth_random_addr in the kernel */
1624 mac->ether_addr_octet[0] &= 0xfe; /* clear multicast bit */
1625 mac->ether_addr_octet[0] |= 0x02; /* set local assignment bit (IEEE802) */
1630 static int setup_veth(pid_t pid, char iface_name[IFNAMSIZ], int *ifi) {
1631 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
1632 _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
1633 struct ether_addr mac_host, mac_container;
1636 if (!arg_private_network)
1639 if (!arg_network_veth)
1642 /* Use two different interface name prefixes depending whether
1643 * we are in bridge mode or not. */
1644 snprintf(iface_name, IFNAMSIZ - 1, "%s-%s",
1645 arg_network_bridge ? "vb" : "ve", arg_machine);
1647 r = generate_mac(&mac_container, CONTAINER_HASH_KEY, 0);
1649 return log_error_errno(r, "Failed to generate predictable MAC address for container side: %m");
1651 r = generate_mac(&mac_host, HOST_HASH_KEY, 0);
1653 return log_error_errno(r, "Failed to generate predictable MAC address for host side: %m");
1655 r = sd_rtnl_open(&rtnl, 0);
1657 return log_error_errno(r, "Failed to connect to netlink: %m");
1659 r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
1661 return log_error_errno(r, "Failed to allocate netlink message: %m");
1663 r = sd_rtnl_message_append_string(m, IFLA_IFNAME, iface_name);
1665 return log_error_errno(r, "Failed to add netlink interface name: %m");
1667 r = sd_rtnl_message_append_ether_addr(m, IFLA_ADDRESS, &mac_host);
1669 return log_error_errno(r, "Failed to add netlink MAC address: %m");
1671 r = sd_rtnl_message_open_container(m, IFLA_LINKINFO);
1673 return log_error_errno(r, "Failed to open netlink container: %m");
1675 r = sd_rtnl_message_open_container_union(m, IFLA_INFO_DATA, "veth");
1677 return log_error_errno(r, "Failed to open netlink container: %m");
1679 r = sd_rtnl_message_open_container(m, VETH_INFO_PEER);
1681 return log_error_errno(r, "Failed to open netlink container: %m");
1683 r = sd_rtnl_message_append_string(m, IFLA_IFNAME, "host0");
1685 return log_error_errno(r, "Failed to add netlink interface name: %m");
1687 r = sd_rtnl_message_append_ether_addr(m, IFLA_ADDRESS, &mac_container);
1689 return log_error_errno(r, "Failed to add netlink MAC address: %m");
1691 r = sd_rtnl_message_append_u32(m, IFLA_NET_NS_PID, pid);
1693 return log_error_errno(r, "Failed to add netlink namespace field: %m");
1695 r = sd_rtnl_message_close_container(m);
1697 return log_error_errno(r, "Failed to close netlink container: %m");
1699 r = sd_rtnl_message_close_container(m);
1701 return log_error_errno(r, "Failed to close netlink container: %m");
1703 r = sd_rtnl_message_close_container(m);
1705 return log_error_errno(r, "Failed to close netlink container: %m");
1707 r = sd_rtnl_call(rtnl, m, 0, NULL);
1709 return log_error_errno(r, "Failed to add new veth interfaces: %m");
1711 i = (int) if_nametoindex(iface_name);
1713 return log_error_errno(errno, "Failed to resolve interface %s: %m", iface_name);
1720 static int setup_bridge(const char veth_name[], int *ifi) {
1721 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
1722 _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
1725 if (!arg_private_network)
1728 if (!arg_network_veth)
1731 if (!arg_network_bridge)
1734 bridge = (int) if_nametoindex(arg_network_bridge);
1736 return log_error_errno(errno, "Failed to resolve interface %s: %m", arg_network_bridge);
1740 r = sd_rtnl_open(&rtnl, 0);
1742 return log_error_errno(r, "Failed to connect to netlink: %m");
1744 r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0);
1746 return log_error_errno(r, "Failed to allocate netlink message: %m");
1748 r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP);
1750 return log_error_errno(r, "Failed to set IFF_UP flag: %m");
1752 r = sd_rtnl_message_append_string(m, IFLA_IFNAME, veth_name);
1754 return log_error_errno(r, "Failed to add netlink interface name field: %m");
1756 r = sd_rtnl_message_append_u32(m, IFLA_MASTER, bridge);
1758 return log_error_errno(r, "Failed to add netlink master field: %m");
1760 r = sd_rtnl_call(rtnl, m, 0, NULL);
1762 return log_error_errno(r, "Failed to add veth interface to bridge: %m");
1767 static int parse_interface(struct udev *udev, const char *name) {
1768 _cleanup_udev_device_unref_ struct udev_device *d = NULL;
1769 char ifi_str[2 + DECIMAL_STR_MAX(int)];
1772 ifi = (int) if_nametoindex(name);
1774 return log_error_errno(errno, "Failed to resolve interface %s: %m", name);
1776 sprintf(ifi_str, "n%i", ifi);
1777 d = udev_device_new_from_device_id(udev, ifi_str);
1779 return log_error_errno(errno, "Failed to get udev device for interface %s: %m", name);
1781 if (udev_device_get_is_initialized(d) <= 0) {
1782 log_error("Network interface %s is not initialized yet.", name);
1789 static int move_network_interfaces(pid_t pid) {
1790 _cleanup_udev_unref_ struct udev *udev = NULL;
1791 _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
1795 if (!arg_private_network)
1798 if (strv_isempty(arg_network_interfaces))
1801 r = sd_rtnl_open(&rtnl, 0);
1803 return log_error_errno(r, "Failed to connect to netlink: %m");
1807 log_error("Failed to connect to udev.");
1811 STRV_FOREACH(i, arg_network_interfaces) {
1812 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
1815 ifi = parse_interface(udev, *i);
1819 r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, ifi);
1821 return log_error_errno(r, "Failed to allocate netlink message: %m");
1823 r = sd_rtnl_message_append_u32(m, IFLA_NET_NS_PID, pid);
1825 return log_error_errno(r, "Failed to append namespace PID to netlink message: %m");
1827 r = sd_rtnl_call(rtnl, m, 0, NULL);
1829 return log_error_errno(r, "Failed to move interface %s to namespace: %m", *i);
1835 static int setup_macvlan(pid_t pid) {
1836 _cleanup_udev_unref_ struct udev *udev = NULL;
1837 _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
1842 if (!arg_private_network)
1845 if (strv_isempty(arg_network_macvlan))
1848 r = sd_rtnl_open(&rtnl, 0);
1850 return log_error_errno(r, "Failed to connect to netlink: %m");
1854 log_error("Failed to connect to udev.");
1858 STRV_FOREACH(i, arg_network_macvlan) {
1859 _cleanup_rtnl_message_unref_ sd_rtnl_message *m = NULL;
1860 _cleanup_free_ char *n = NULL;
1861 struct ether_addr mac;
1864 ifi = parse_interface(udev, *i);
1868 r = generate_mac(&mac, MACVLAN_HASH_KEY, idx++);
1870 return log_error_errno(r, "Failed to create MACVLAN MAC address: %m");
1872 r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
1874 return log_error_errno(r, "Failed to allocate netlink message: %m");
1876 r = sd_rtnl_message_append_u32(m, IFLA_LINK, ifi);
1878 return log_error_errno(r, "Failed to add netlink interface index: %m");
1880 n = strappend("mv-", *i);
1884 strshorten(n, IFNAMSIZ-1);
1886 r = sd_rtnl_message_append_string(m, IFLA_IFNAME, n);
1888 return log_error_errno(r, "Failed to add netlink interface name: %m");
1890 r = sd_rtnl_message_append_ether_addr(m, IFLA_ADDRESS, &mac);
1892 return log_error_errno(r, "Failed to add netlink MAC address: %m");
1894 r = sd_rtnl_message_append_u32(m, IFLA_NET_NS_PID, pid);
1896 return log_error_errno(r, "Failed to add netlink namespace field: %m");
1898 r = sd_rtnl_message_open_container(m, IFLA_LINKINFO);
1900 return log_error_errno(r, "Failed to open netlink container: %m");
1902 r = sd_rtnl_message_open_container_union(m, IFLA_INFO_DATA, "macvlan");
1904 return log_error_errno(r, "Failed to open netlink container: %m");
1906 r = sd_rtnl_message_append_u32(m, IFLA_MACVLAN_MODE, MACVLAN_MODE_BRIDGE);
1908 return log_error_errno(r, "Failed to append macvlan mode: %m");
1910 r = sd_rtnl_message_close_container(m);
1912 return log_error_errno(r, "Failed to close netlink container: %m");
1914 r = sd_rtnl_message_close_container(m);
1916 return log_error_errno(r, "Failed to close netlink container: %m");
1918 r = sd_rtnl_call(rtnl, m, 0, NULL);
1920 return log_error_errno(r, "Failed to add new macvlan interfaces: %m");
1926 static int setup_seccomp(void) {
1929 static const int blacklist[] = {
1930 SCMP_SYS(kexec_load),
1931 SCMP_SYS(open_by_handle_at),
1932 SCMP_SYS(init_module),
1933 SCMP_SYS(finit_module),
1934 SCMP_SYS(delete_module),
1941 scmp_filter_ctx seccomp;
1945 seccomp = seccomp_init(SCMP_ACT_ALLOW);
1949 r = seccomp_add_secondary_archs(seccomp);
1951 log_error_errno(r, "Failed to add secondary archs to seccomp filter: %m");
1955 for (i = 0; i < ELEMENTSOF(blacklist); i++) {
1956 r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i], 0);
1958 continue; /* unknown syscall */
1960 log_error_errno(r, "Failed to block syscall: %m");
1966 Audit is broken in containers, much of the userspace audit
1967 hookup will fail if running inside a container. We don't
1968 care and just turn off creation of audit sockets.
1970 This will make socket(AF_NETLINK, *, NETLINK_AUDIT) fail
1971 with EAFNOSUPPORT which audit userspace uses as indication
1972 that audit is disabled in the kernel.
1975 r = seccomp_rule_add(
1977 SCMP_ACT_ERRNO(EAFNOSUPPORT),
1980 SCMP_A0(SCMP_CMP_EQ, AF_NETLINK),
1981 SCMP_A2(SCMP_CMP_EQ, NETLINK_AUDIT));
1983 log_error_errno(r, "Failed to add audit seccomp rule: %m");
1987 r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0);
1989 log_error_errno(r, "Failed to unset NO_NEW_PRIVS: %m");
1993 r = seccomp_load(seccomp);
1995 log_error_errno(r, "Failed to install seccomp audit filter: %m");
1998 seccomp_release(seccomp);
2006 static int setup_image(char **device_path, int *loop_nr) {
2007 struct loop_info64 info = {
2008 .lo_flags = LO_FLAGS_AUTOCLEAR|LO_FLAGS_PARTSCAN
2010 _cleanup_close_ int fd = -1, control = -1, loop = -1;
2011 _cleanup_free_ char* loopdev = NULL;
2015 assert(device_path);
2018 fd = open(arg_image, O_CLOEXEC|(arg_read_only ? O_RDONLY : O_RDWR)|O_NONBLOCK|O_NOCTTY);
2020 return log_error_errno(errno, "Failed to open %s: %m", arg_image);
2022 if (fstat(fd, &st) < 0)
2023 return log_error_errno(errno, "Failed to stat %s: %m", arg_image);
2025 if (S_ISBLK(st.st_mode)) {
2028 p = strdup(arg_image);
2042 if (!S_ISREG(st.st_mode)) {
2043 log_error_errno(errno, "%s is not a regular file or block device: %m", arg_image);
2047 control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
2049 return log_error_errno(errno, "Failed to open /dev/loop-control: %m");
2051 nr = ioctl(control, LOOP_CTL_GET_FREE);
2053 return log_error_errno(errno, "Failed to allocate loop device: %m");
2055 if (asprintf(&loopdev, "/dev/loop%i", nr) < 0)
2058 loop = open(loopdev, O_CLOEXEC|(arg_read_only ? O_RDONLY : O_RDWR)|O_NONBLOCK|O_NOCTTY);
2060 return log_error_errno(errno, "Failed to open loop device %s: %m", loopdev);
2062 if (ioctl(loop, LOOP_SET_FD, fd) < 0)
2063 return log_error_errno(errno, "Failed to set loopback file descriptor on %s: %m", loopdev);
2066 info.lo_flags |= LO_FLAGS_READ_ONLY;
2068 if (ioctl(loop, LOOP_SET_STATUS64, &info) < 0)
2069 return log_error_errno(errno, "Failed to set loopback settings on %s: %m", loopdev);
2071 *device_path = loopdev;
2082 static int dissect_image(
2084 char **root_device, bool *root_device_rw,
2085 char **home_device, bool *home_device_rw,
2086 char **srv_device, bool *srv_device_rw,
2090 int home_nr = -1, srv_nr = -1;
2091 #ifdef GPT_ROOT_NATIVE
2094 #ifdef GPT_ROOT_SECONDARY
2095 int secondary_root_nr = -1;
2098 _cleanup_free_ char *home = NULL, *root = NULL, *secondary_root = NULL, *srv = NULL;
2099 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
2100 _cleanup_udev_device_unref_ struct udev_device *d = NULL;
2101 _cleanup_blkid_free_probe_ blkid_probe b = NULL;
2102 _cleanup_udev_unref_ struct udev *udev = NULL;
2103 struct udev_list_entry *first, *item;
2104 bool home_rw = true, root_rw = true, secondary_root_rw = true, srv_rw = true;
2105 const char *pttype = NULL;
2111 assert(root_device);
2112 assert(home_device);
2116 b = blkid_new_probe();
2121 r = blkid_probe_set_device(b, fd, 0, 0);
2126 log_error_errno(errno, "Failed to set device on blkid probe: %m");
2130 blkid_probe_enable_partitions(b, 1);
2131 blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS);
2134 r = blkid_do_safeprobe(b);
2135 if (r == -2 || r == 1) {
2136 log_error("Failed to identify any partition table on %s.\n"
2137 "Note that the disk image needs to follow http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/ to be supported by systemd-nspawn.", arg_image);
2139 } else if (r != 0) {
2142 log_error_errno(errno, "Failed to probe: %m");
2146 blkid_probe_lookup_value(b, "PTTYPE", &pttype, NULL);
2147 if (!streq_ptr(pttype, "gpt")) {
2148 log_error("Image %s does not carry a GUID Partition Table.\n"
2149 "Note that the disk image needs to follow http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/ to be supported by systemd-nspawn.", arg_image);
2154 pl = blkid_probe_get_partitions(b);
2159 log_error("Failed to list partitions of %s", arg_image);
2167 if (fstat(fd, &st) < 0)
2168 return log_error_errno(errno, "Failed to stat block device: %m");
2170 d = udev_device_new_from_devnum(udev, 'b', st.st_rdev);
2174 e = udev_enumerate_new(udev);
2178 r = udev_enumerate_add_match_parent(e, d);
2182 r = udev_enumerate_scan_devices(e);
2184 return log_error_errno(r, "Failed to scan for partition devices of %s: %m", arg_image);
2186 first = udev_enumerate_get_list_entry(e);
2187 udev_list_entry_foreach(item, first) {
2188 _cleanup_udev_device_unref_ struct udev_device *q;
2189 const char *stype, *node;
2190 unsigned long long flags;
2197 q = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
2202 log_error_errno(errno, "Failed to get partition device of %s: %m", arg_image);
2206 qn = udev_device_get_devnum(q);
2210 if (st.st_rdev == qn)
2213 node = udev_device_get_devnode(q);
2217 pp = blkid_partlist_devno_to_partition(pl, qn);
2221 flags = blkid_partition_get_flags(pp);
2222 if (flags & GPT_FLAG_NO_AUTO)
2225 nr = blkid_partition_get_partno(pp);
2229 stype = blkid_partition_get_type_string(pp);
2233 if (sd_id128_from_string(stype, &type_id) < 0)
2236 if (sd_id128_equal(type_id, GPT_HOME)) {
2238 if (home && nr >= home_nr)
2242 home_rw = !(flags & GPT_FLAG_READ_ONLY);
2245 home = strdup(node);
2248 } else if (sd_id128_equal(type_id, GPT_SRV)) {
2250 if (srv && nr >= srv_nr)
2254 srv_rw = !(flags & GPT_FLAG_READ_ONLY);
2261 #ifdef GPT_ROOT_NATIVE
2262 else if (sd_id128_equal(type_id, GPT_ROOT_NATIVE)) {
2264 if (root && nr >= root_nr)
2268 root_rw = !(flags & GPT_FLAG_READ_ONLY);
2271 root = strdup(node);
2276 #ifdef GPT_ROOT_SECONDARY
2277 else if (sd_id128_equal(type_id, GPT_ROOT_SECONDARY)) {
2279 if (secondary_root && nr >= secondary_root_nr)
2282 secondary_root_nr = nr;
2283 secondary_root_rw = !(flags & GPT_FLAG_READ_ONLY);
2286 free(secondary_root);
2287 secondary_root = strdup(node);
2288 if (!secondary_root)
2294 if (!root && !secondary_root) {
2295 log_error("Failed to identify root partition in disk image %s.\n"
2296 "Note that the disk image needs to follow http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/ to be supported by systemd-nspawn.", arg_image);
2301 *root_device = root;
2304 *root_device_rw = root_rw;
2306 } else if (secondary_root) {
2307 *root_device = secondary_root;
2308 secondary_root = NULL;
2310 *root_device_rw = secondary_root_rw;
2315 *home_device = home;
2318 *home_device_rw = home_rw;
2325 *srv_device_rw = srv_rw;
2330 log_error("--image= is not supported, compiled without blkid support.");
2335 static int mount_device(const char *what, const char *where, const char *directory, bool rw) {
2337 _cleanup_blkid_free_probe_ blkid_probe b = NULL;
2338 const char *fstype, *p;
2348 p = strappenda(where, directory);
2353 b = blkid_new_probe_from_filename(what);
2357 log_error_errno(errno, "Failed to allocate prober for %s: %m", what);
2361 blkid_probe_enable_superblocks(b, 1);
2362 blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE);
2365 r = blkid_do_safeprobe(b);
2366 if (r == -1 || r == 1) {
2367 log_error("Cannot determine file system type of %s", what);
2369 } else if (r != 0) {
2372 log_error_errno(errno, "Failed to probe %s: %m", what);
2377 if (blkid_probe_lookup_value(b, "TYPE", &fstype, NULL) < 0) {
2380 log_error("Failed to determine file system type of %s", what);
2384 if (streq(fstype, "crypto_LUKS")) {
2385 log_error("nspawn currently does not support LUKS disk images.");
2389 if (mount(what, p, fstype, MS_NODEV|(rw ? 0 : MS_RDONLY), NULL) < 0)
2390 return log_error_errno(errno, "Failed to mount %s: %m", what);
2394 log_error("--image= is not supported, compiled without blkid support.");
2399 static int mount_devices(
2401 const char *root_device, bool root_device_rw,
2402 const char *home_device, bool home_device_rw,
2403 const char *srv_device, bool srv_device_rw) {
2409 r = mount_device(root_device, arg_directory, NULL, root_device_rw);
2411 return log_error_errno(r, "Failed to mount root directory: %m");
2415 r = mount_device(home_device, arg_directory, "/home", home_device_rw);
2417 return log_error_errno(r, "Failed to mount home directory: %m");
2421 r = mount_device(srv_device, arg_directory, "/srv", srv_device_rw);
2423 return log_error_errno(r, "Failed to mount server data directory: %m");
2429 static void loop_remove(int nr, int *image_fd) {
2430 _cleanup_close_ int control = -1;
2436 if (image_fd && *image_fd >= 0) {
2437 r = ioctl(*image_fd, LOOP_CLR_FD);
2439 log_warning_errno(errno, "Failed to close loop image: %m");
2440 *image_fd = safe_close(*image_fd);
2443 control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
2445 log_warning_errno(errno, "Failed to open /dev/loop-control: %m");
2449 r = ioctl(control, LOOP_CTL_REMOVE, nr);
2451 log_warning_errno(errno, "Failed to remove loop %d: %m", nr);
2454 static int spawn_getent(const char *database, const char *key, pid_t *rpid) {
2462 if (pipe2(pipe_fds, O_CLOEXEC) < 0)
2463 return log_error_errno(errno, "Failed to allocate pipe: %m");
2467 return log_error_errno(errno, "Failed to fork getent child: %m");
2468 else if (pid == 0) {
2470 char *empty_env = NULL;
2472 if (dup3(pipe_fds[1], STDOUT_FILENO, 0) < 0)
2473 _exit(EXIT_FAILURE);
2475 if (pipe_fds[0] > 2)
2476 safe_close(pipe_fds[0]);
2477 if (pipe_fds[1] > 2)
2478 safe_close(pipe_fds[1]);
2480 nullfd = open("/dev/null", O_RDWR);
2482 _exit(EXIT_FAILURE);
2484 if (dup3(nullfd, STDIN_FILENO, 0) < 0)
2485 _exit(EXIT_FAILURE);
2487 if (dup3(nullfd, STDERR_FILENO, 0) < 0)
2488 _exit(EXIT_FAILURE);
2493 reset_all_signal_handlers();
2494 close_all_fds(NULL, 0);
2496 execle("/usr/bin/getent", "getent", database, key, NULL, &empty_env);
2497 execle("/bin/getent", "getent", database, key, NULL, &empty_env);
2498 _exit(EXIT_FAILURE);
2501 pipe_fds[1] = safe_close(pipe_fds[1]);
2508 static int change_uid_gid(char **_home) {
2509 char line[LINE_MAX], *x, *u, *g, *h;
2510 const char *word, *state;
2511 _cleanup_free_ uid_t *uids = NULL;
2512 _cleanup_free_ char *home = NULL;
2513 _cleanup_fclose_ FILE *f = NULL;
2514 _cleanup_close_ int fd = -1;
2515 unsigned n_uids = 0;
2524 if (!arg_user || streq(arg_user, "root") || streq(arg_user, "0")) {
2525 /* Reset everything fully to 0, just in case */
2527 if (setgroups(0, NULL) < 0)
2528 return log_error_errno(errno, "setgroups() failed: %m");
2530 if (setresgid(0, 0, 0) < 0)
2531 return log_error_errno(errno, "setregid() failed: %m");
2533 if (setresuid(0, 0, 0) < 0)
2534 return log_error_errno(errno, "setreuid() failed: %m");
2540 /* First, get user credentials */
2541 fd = spawn_getent("passwd", arg_user, &pid);
2545 f = fdopen(fd, "r");
2550 if (!fgets(line, sizeof(line), f)) {
2553 log_error("Failed to resolve user %s.", arg_user);
2557 log_error_errno(errno, "Failed to read from getent: %m");
2563 wait_for_terminate_and_warn("getent passwd", pid, true);
2565 x = strchr(line, ':');
2567 log_error("/etc/passwd entry has invalid user field.");
2571 u = strchr(x+1, ':');
2573 log_error("/etc/passwd entry has invalid password field.");
2580 log_error("/etc/passwd entry has invalid UID field.");
2588 log_error("/etc/passwd entry has invalid GID field.");
2593 h = strchr(x+1, ':');
2595 log_error("/etc/passwd entry has invalid GECOS field.");
2602 log_error("/etc/passwd entry has invalid home directory field.");
2608 r = parse_uid(u, &uid);
2610 log_error("Failed to parse UID of user.");
2614 r = parse_gid(g, &gid);
2616 log_error("Failed to parse GID of user.");
2624 /* Second, get group memberships */
2625 fd = spawn_getent("initgroups", arg_user, &pid);
2630 f = fdopen(fd, "r");
2635 if (!fgets(line, sizeof(line), f)) {
2637 log_error("Failed to resolve user %s.", arg_user);
2641 log_error_errno(errno, "Failed to read from getent: %m");
2647 wait_for_terminate_and_warn("getent initgroups", pid, true);
2649 /* Skip over the username and subsequent separator whitespace */
2651 x += strcspn(x, WHITESPACE);
2652 x += strspn(x, WHITESPACE);
2654 FOREACH_WORD(word, l, x, state) {
2660 if (!GREEDY_REALLOC(uids, sz, n_uids+1))
2663 r = parse_uid(c, &uids[n_uids++]);
2665 log_error("Failed to parse group data from getent.");
2670 r = mkdir_parents(home, 0775);
2672 return log_error_errno(r, "Failed to make home root directory: %m");
2674 r = mkdir_safe(home, 0755, uid, gid);
2675 if (r < 0 && r != -EEXIST)
2676 return log_error_errno(r, "Failed to make home directory: %m");
2678 fchown(STDIN_FILENO, uid, gid);
2679 fchown(STDOUT_FILENO, uid, gid);
2680 fchown(STDERR_FILENO, uid, gid);
2682 if (setgroups(n_uids, uids) < 0)
2683 return log_error_errno(errno, "Failed to set auxiliary groups: %m");
2685 if (setresgid(gid, gid, gid) < 0)
2686 return log_error_errno(errno, "setregid() failed: %m");
2688 if (setresuid(uid, uid, uid) < 0)
2689 return log_error_errno(errno, "setreuid() failed: %m");
2701 * < 0 : wait_for_terminate() failed to get the state of the
2702 * container, the container was terminated by a signal, or
2703 * failed for an unknown reason. No change is made to the
2704 * container argument.
2705 * > 0 : The program executed in the container terminated with an
2706 * error. The exit code of the program executed in the
2707 * container is returned. The container argument has been set
2708 * to CONTAINER_TERMINATED.
2709 * 0 : The container is being rebooted, has been shut down or exited
2710 * successfully. The container argument has been set to either
2711 * CONTAINER_TERMINATED or CONTAINER_REBOOTED.
2713 * That is, success is indicated by a return value of zero, and an
2714 * error is indicated by a non-zero value.
2716 static int wait_for_container(pid_t pid, ContainerStatus *container) {
2720 r = wait_for_terminate(pid, &status);
2722 return log_warning_errno(r, "Failed to wait for container: %m");
2724 switch (status.si_code) {
2727 if (status.si_status == 0) {
2728 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s exited successfully.", arg_machine);
2731 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s failed with error code %i.", arg_machine, status.si_status);
2733 *container = CONTAINER_TERMINATED;
2734 return status.si_status;
2737 if (status.si_status == SIGINT) {
2739 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s has been shut down.", arg_machine);
2740 *container = CONTAINER_TERMINATED;
2743 } else if (status.si_status == SIGHUP) {
2745 log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s is being rebooted.", arg_machine);
2746 *container = CONTAINER_REBOOTED;
2750 /* CLD_KILLED fallthrough */
2753 log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status));
2757 log_error("Container %s failed due to unknown reason.", arg_machine);
2764 static void nop_handler(int sig) {}
2766 static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
2769 pid = PTR_TO_UINT32(userdata);
2771 if (kill(pid, SIGRTMIN+3) >= 0) {
2772 log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
2773 sd_event_source_set_userdata(s, NULL);
2778 sd_event_exit(sd_event_source_get_event(s), 0);
2782 int main(int argc, char *argv[]) {
2784 _cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL;
2785 bool root_device_rw = true, home_device_rw = true, srv_device_rw = true;
2786 _cleanup_close_ int master = -1, image_fd = -1;
2787 _cleanup_close_pair_ int kmsg_socket_pair[2] = { -1, -1 };
2788 _cleanup_fdset_free_ FDSet *fds = NULL;
2789 int r = EXIT_FAILURE, k, n_fd_passed, loop_nr = -1;
2790 const char *console = NULL;
2791 char veth_name[IFNAMSIZ];
2792 bool secondary = false;
2793 sigset_t mask, mask_chld;
2796 log_parse_environment();
2799 k = parse_argv(argc, argv);
2808 if (arg_directory) {
2811 p = path_make_absolute_cwd(arg_directory);
2812 free(arg_directory);
2815 arg_directory = get_current_dir_name();
2817 if (!arg_directory) {
2818 log_error("Failed to determine path, please use -D.");
2821 path_kill_slashes(arg_directory);
2825 arg_machine = strdup(basename(arg_image ? arg_image : arg_directory));
2831 hostname_cleanup(arg_machine, false);
2832 if (isempty(arg_machine)) {
2833 log_error("Failed to determine machine name automatically, please use -M.");
2838 if (geteuid() != 0) {
2839 log_error("Need to be root.");
2843 if (sd_booted() <= 0) {
2844 log_error("Not running on a systemd system.");
2849 n_fd_passed = sd_listen_fds(false);
2850 if (n_fd_passed > 0) {
2851 k = fdset_new_listen_fds(&fds, false);
2853 log_error_errno(k, "Failed to collect file descriptors: %m");
2857 fdset_close_others(fds);
2860 if (arg_directory) {
2861 if (path_equal(arg_directory, "/")) {
2862 log_error("Spawning container on root directory not supported.");
2867 if (path_is_os_tree(arg_directory) <= 0) {
2868 log_error("Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", arg_directory);
2874 p = strappenda(arg_directory,
2875 argc > optind && path_is_absolute(argv[optind]) ? argv[optind] : "/usr/bin/");
2876 if (access(p, F_OK) < 0) {
2877 log_error("Directory %s lacks the binary to execute or doesn't look like a binary tree. Refusing.", arg_directory);
2883 char template[] = "/tmp/nspawn-root-XXXXXX";
2885 if (!mkdtemp(template)) {
2886 log_error_errno(errno, "Failed to create temporary directory: %m");
2891 arg_directory = strdup(template);
2892 if (!arg_directory) {
2897 image_fd = setup_image(&device_path, &loop_nr);
2903 r = dissect_image(image_fd,
2904 &root_device, &root_device_rw,
2905 &home_device, &home_device_rw,
2906 &srv_device, &srv_device_rw,
2912 master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY);
2914 log_error_errno(errno, "Failed to acquire pseudo tty: %m");
2918 console = ptsname(master);
2920 log_error_errno(errno, "Failed to determine tty name: %m");
2925 log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.",
2926 arg_machine, arg_image ? arg_image : arg_directory);
2928 if (unlockpt(master) < 0) {
2929 log_error_errno(errno, "Failed to unlock tty: %m");
2933 if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
2934 log_error_errno(errno, "Failed to create kmsg socket pair: %m");
2940 "STATUS=Container running.");
2942 assert_se(sigemptyset(&mask) == 0);
2943 sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1);
2944 assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0);
2946 assert_se(sigemptyset(&mask_chld) == 0);
2947 assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
2950 ContainerStatus container_status;
2951 _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
2952 struct sigaction sa = {
2953 .sa_handler = nop_handler,
2954 .sa_flags = SA_NOCLDSTOP,
2957 r = barrier_create(&barrier);
2959 log_error_errno(r, "Cannot initialize IPC barrier: %m");
2963 /* Child can be killed before execv(), so handle SIGCHLD
2964 * in order to interrupt parent's blocking calls and
2965 * give it a chance to call wait() and terminate. */
2966 r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL);
2968 log_error_errno(errno, "Failed to change the signal mask: %m");
2972 r = sigaction(SIGCHLD, &sa, NULL);
2974 log_error_errno(errno, "Failed to install SIGCHLD handler: %m");
2978 pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWNS|
2979 (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)|
2980 (arg_private_network ? CLONE_NEWNET : 0), NULL);
2982 if (errno == EINVAL)
2983 log_error_errno(errno, "clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m");
2985 log_error_errno(errno, "clone() failed: %m");
2993 _cleanup_free_ char *home = NULL;
2995 const char *envp[] = {
2996 "PATH=" DEFAULT_PATH_SPLIT_USR,
2997 "container=systemd-nspawn", /* LXC sets container=lxc, so follow the scheme here */
3002 NULL, /* container_uuid */
3003 NULL, /* LISTEN_FDS */
3004 NULL, /* LISTEN_PID */
3009 barrier_set_role(&barrier, BARRIER_CHILD);
3011 envp[n_env] = strv_find_prefix(environ, "TERM=");
3015 master = safe_close(master);
3017 close_nointr(STDIN_FILENO);
3018 close_nointr(STDOUT_FILENO);
3019 close_nointr(STDERR_FILENO);
3021 kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]);
3023 reset_all_signal_handlers();
3024 reset_signal_mask();
3026 k = open_terminal(console, O_RDWR);
3027 if (k != STDIN_FILENO) {
3033 log_error_errno(k, "Failed to open console: %m");
3034 _exit(EXIT_FAILURE);
3037 if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
3038 dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
3039 log_error_errno(errno, "Failed to duplicate console: %m");
3040 _exit(EXIT_FAILURE);
3044 log_error_errno(errno, "setsid() failed: %m");
3045 _exit(EXIT_FAILURE);
3048 if (reset_audit_loginuid() < 0)
3049 _exit(EXIT_FAILURE);
3051 if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) {
3052 log_error_errno(errno, "PR_SET_PDEATHSIG failed: %m");
3053 _exit(EXIT_FAILURE);
3056 /* Mark everything as slave, so that we still
3057 * receive mounts from the real root, but don't
3058 * propagate mounts to the real root. */
3059 if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
3060 log_error_errno(errno, "MS_SLAVE|MS_REC failed: %m");
3061 _exit(EXIT_FAILURE);
3064 if (mount_devices(arg_directory,
3065 root_device, root_device_rw,
3066 home_device, home_device_rw,
3067 srv_device, srv_device_rw) < 0)
3068 _exit(EXIT_FAILURE);
3070 /* Turn directory into bind mount */
3071 if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REC, NULL) < 0) {
3072 log_error_errno(errno, "Failed to make bind mount: %m");
3073 _exit(EXIT_FAILURE);
3076 r = setup_volatile(arg_directory);
3078 _exit(EXIT_FAILURE);
3080 if (setup_volatile_state(arg_directory) < 0)
3081 _exit(EXIT_FAILURE);
3083 r = base_filesystem_create(arg_directory);
3085 _exit(EXIT_FAILURE);
3087 if (arg_read_only) {
3088 k = bind_remount_recursive(arg_directory, true);
3090 log_error_errno(k, "Failed to make tree read-only: %m");
3091 _exit(EXIT_FAILURE);
3095 if (mount_all(arg_directory) < 0)
3096 _exit(EXIT_FAILURE);
3098 if (copy_devnodes(arg_directory) < 0)
3099 _exit(EXIT_FAILURE);
3101 if (setup_ptmx(arg_directory) < 0)
3102 _exit(EXIT_FAILURE);
3104 dev_setup(arg_directory);
3106 if (setup_seccomp() < 0)
3107 _exit(EXIT_FAILURE);
3109 if (setup_dev_console(arg_directory, console) < 0)
3110 _exit(EXIT_FAILURE);
3112 if (setup_kmsg(arg_directory, kmsg_socket_pair[1]) < 0)
3113 _exit(EXIT_FAILURE);
3115 kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
3117 if (setup_boot_id(arg_directory) < 0)
3118 _exit(EXIT_FAILURE);
3120 if (setup_timezone(arg_directory) < 0)
3121 _exit(EXIT_FAILURE);
3123 if (setup_resolv_conf(arg_directory) < 0)
3124 _exit(EXIT_FAILURE);
3126 if (setup_journal(arg_directory) < 0)
3127 _exit(EXIT_FAILURE);
3129 if (mount_binds(arg_directory, arg_bind, false) < 0)
3130 _exit(EXIT_FAILURE);
3132 if (mount_binds(arg_directory, arg_bind_ro, true) < 0)
3133 _exit(EXIT_FAILURE);
3135 if (mount_tmpfs(arg_directory) < 0)
3136 _exit(EXIT_FAILURE);
3138 /* Tell the parent that we are ready, and that
3139 * it can cgroupify us to that we lack access
3140 * to certain devices and resources. */
3141 (void)barrier_place(&barrier);
3143 if (chdir(arg_directory) < 0) {
3144 log_error_errno(errno, "chdir(%s) failed: %m", arg_directory);
3145 _exit(EXIT_FAILURE);
3148 if (mount(arg_directory, "/", NULL, MS_MOVE, NULL) < 0) {
3149 log_error_errno(errno, "mount(MS_MOVE) failed: %m");
3150 _exit(EXIT_FAILURE);
3153 if (chroot(".") < 0) {
3154 log_error_errno(errno, "chroot() failed: %m");
3155 _exit(EXIT_FAILURE);
3158 if (chdir("/") < 0) {
3159 log_error_errno(errno, "chdir() failed: %m");
3160 _exit(EXIT_FAILURE);
3165 if (arg_private_network)
3168 if (drop_capabilities() < 0) {
3169 log_error_errno(errno, "drop_capabilities() failed: %m");
3170 _exit(EXIT_FAILURE);
3173 r = change_uid_gid(&home);
3175 _exit(EXIT_FAILURE);
3177 if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) ||
3178 (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) ||
3179 (asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) {
3181 _exit(EXIT_FAILURE);
3184 if (!sd_id128_equal(arg_uuid, SD_ID128_NULL)) {
3187 if (asprintf((char**)(envp + n_env++), "container_uuid=%s", id128_format_as_uuid(arg_uuid, as_uuid)) < 0) {
3189 _exit(EXIT_FAILURE);
3193 if (fdset_size(fds) > 0) {
3194 k = fdset_cloexec(fds, false);
3196 log_error("Failed to unset O_CLOEXEC for file descriptors.");
3197 _exit(EXIT_FAILURE);
3200 if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) ||
3201 (asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0)) {
3203 _exit(EXIT_FAILURE);
3209 if (arg_personality != 0xffffffffLU) {
3210 if (personality(arg_personality) < 0) {
3211 log_error_errno(errno, "personality() failed: %m");
3212 _exit(EXIT_FAILURE);
3214 } else if (secondary) {
3215 if (personality(PER_LINUX32) < 0) {
3216 log_error_errno(errno, "personality() failed: %m");
3217 _exit(EXIT_FAILURE);
3222 if (arg_selinux_context)
3223 if (setexeccon((security_context_t) arg_selinux_context) < 0) {
3224 log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context);
3225 _exit(EXIT_FAILURE);
3229 if (!strv_isempty(arg_setenv)) {
3232 n = strv_env_merge(2, envp, arg_setenv);
3235 _exit(EXIT_FAILURE);
3240 env_use = (char**) envp;
3242 /* Wait until the parent is ready with the setup, too... */
3243 if (!barrier_place_and_sync(&barrier))
3244 _exit(EXIT_FAILURE);
3250 /* Automatically search for the init system */
3252 l = 1 + argc - optind;
3253 a = newa(char*, l + 1);
3254 memcpy(a + 1, argv + optind, l * sizeof(char*));
3256 a[0] = (char*) "/usr/lib/systemd/systemd";
3257 execve(a[0], a, env_use);
3259 a[0] = (char*) "/lib/systemd/systemd";
3260 execve(a[0], a, env_use);
3262 a[0] = (char*) "/sbin/init";
3263 execve(a[0], a, env_use);
3264 } else if (argc > optind)
3265 execvpe(argv[optind], argv + optind, env_use);
3267 chdir(home ? home : "/root");
3268 execle("/bin/bash", "-bash", NULL, env_use);
3269 execle("/bin/sh", "-sh", NULL, env_use);
3272 log_error_errno(errno, "execv() failed: %m");
3273 _exit(EXIT_FAILURE);
3276 barrier_set_role(&barrier, BARRIER_PARENT);
3280 /* wait for child-setup to be done */
3281 if (barrier_place_and_sync(&barrier)) {
3282 _cleanup_event_unref_ sd_event *event = NULL;
3283 _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
3286 r = move_network_interfaces(pid);
3290 r = setup_veth(pid, veth_name, &ifi);
3294 r = setup_bridge(veth_name, &ifi);
3298 r = setup_macvlan(pid);
3302 r = register_machine(pid, ifi);
3306 /* Block SIGCHLD here, before notifying child.
3307 * process_pty() will handle it with the other signals. */
3308 r = sigprocmask(SIG_BLOCK, &mask_chld, NULL);
3312 /* Reset signal to default */
3313 r = default_signals(SIGCHLD, -1);
3317 /* Notify the child that the parent is ready with all
3318 * its setup, and that the child can now hand over
3319 * control to the code to run inside the container. */
3320 (void)barrier_place(&barrier);
3322 r = sd_event_new(&event);
3324 log_error_errno(r, "Failed to get default event source: %m");
3329 /* Try to kill the init system on SIGINT or SIGTERM */
3330 sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, UINT32_TO_PTR(pid));
3331 sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, UINT32_TO_PTR(pid));
3333 /* Immediately exit */
3334 sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
3335 sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
3338 /* simply exit on sigchld */
3339 sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
3341 r = pty_forward_new(event, master, &forward);
3343 log_error_errno(r, "Failed to create PTY forwarder: %m");
3347 r = sd_event_loop(event);
3349 return log_error_errno(r, "Failed to run event loop: %m");
3351 forward = pty_forward_free(forward);
3356 /* Kill if it is not dead yet anyway */
3357 terminate_machine(pid);
3360 /* Normally redundant, but better safe than sorry */
3363 r = wait_for_container(pid, &container_status);
3367 /* We failed to wait for the container, or the
3368 * container exited abnormally */
3371 } else if (r > 0 || container_status == CONTAINER_TERMINATED)
3372 /* The container exited with a non-zero
3373 * status, or with zero status and no reboot
3377 /* CONTAINER_REBOOTED, loop again */
3379 if (arg_keep_unit) {
3380 /* Special handling if we are running as a
3381 * service: instead of simply restarting the
3382 * machine we want to restart the entire
3383 * service, so let's inform systemd about this
3384 * with the special exit code 133. The service
3385 * file uses RestartForceExitStatus=133 so
3386 * that this results in a full nspawn
3387 * restart. This is necessary since we might
3388 * have cgroup parameters set we want to have
3398 "STATUS=Terminating...");
3400 loop_remove(loop_nr, &image_fd);
3405 free(arg_directory);
3408 strv_free(arg_setenv);
3409 strv_free(arg_network_interfaces);
3410 strv_free(arg_network_macvlan);
3411 strv_free(arg_bind);
3412 strv_free(arg_bind_ro);
3413 strv_free(arg_tmpfs);