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/epoll.h>
39 #include <sys/signalfd.h>
43 #include <sys/socket.h>
44 #include <linux/netlink.h>
46 #include <systemd/sd-daemon.h>
47 #include <systemd/sd-bus.h>
55 #include "cgroup-util.h"
57 #include "path-util.h"
58 #include "loopback-setup.h"
60 #include "dev-setup.h"
71 typedef enum LinkJournal {
78 static char *arg_directory = NULL;
79 static char *arg_user = NULL;
80 static sd_id128_t arg_uuid = {};
81 static char *arg_machine = NULL;
82 static const char *arg_slice = NULL;
83 static bool arg_private_network = false;
84 static bool arg_read_only = false;
85 static bool arg_boot = false;
86 static LinkJournal arg_link_journal = LINK_AUTO;
87 static uint64_t arg_retain =
89 (1ULL << CAP_DAC_OVERRIDE) |
90 (1ULL << CAP_DAC_READ_SEARCH) |
91 (1ULL << CAP_FOWNER) |
92 (1ULL << CAP_FSETID) |
93 (1ULL << CAP_IPC_OWNER) |
96 (1ULL << CAP_LINUX_IMMUTABLE) |
97 (1ULL << CAP_NET_BIND_SERVICE) |
98 (1ULL << CAP_NET_BROADCAST) |
99 (1ULL << CAP_NET_RAW) |
100 (1ULL << CAP_SETGID) |
101 (1ULL << CAP_SETFCAP) |
102 (1ULL << CAP_SETPCAP) |
103 (1ULL << CAP_SETUID) |
104 (1ULL << CAP_SYS_ADMIN) |
105 (1ULL << CAP_SYS_CHROOT) |
106 (1ULL << CAP_SYS_NICE) |
107 (1ULL << CAP_SYS_PTRACE) |
108 (1ULL << CAP_SYS_TTY_CONFIG) |
109 (1ULL << CAP_SYS_RESOURCE) |
110 (1ULL << CAP_SYS_BOOT) |
111 (1ULL << CAP_AUDIT_WRITE) |
112 (1ULL << CAP_AUDIT_CONTROL);
113 static char **arg_bind = NULL;
114 static char **arg_bind_ro = NULL;
116 static int help(void) {
118 printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
119 "Spawn a minimal namespace container for debugging, testing and building.\n\n"
120 " -h --help Show this help\n"
121 " --version Print version string\n"
122 " -D --directory=NAME Root directory for the container\n"
123 " -b --boot Boot up full system (i.e. invoke init)\n"
124 " -u --user=USER Run the command under specified user or uid\n"
125 " --uuid=UUID Set a specific machine UUID for the container\n"
126 " -M --machine=NAME Set the machine name for the container\n"
127 " -S --slice=SLICE Place the container in the specified slice\n"
128 " --private-network Disable network in container\n"
129 " --read-only Mount the root directory read-only\n"
130 " --capability=CAP In addition to the default, retain specified\n"
132 " --link-journal=MODE Link up guest journal, one of no, auto, guest, host\n"
133 " -j Equivalent to --link-journal=host\n"
134 " --bind=PATH[:PATH] Bind mount a file or directory from the host into\n"
136 " --bind-ro=PATH[:PATH] Similar, but creates a read-only bind mount\n",
137 program_invocation_short_name);
142 static int parse_argv(int argc, char *argv[]) {
155 static const struct option options[] = {
156 { "help", no_argument, NULL, 'h' },
157 { "version", no_argument, NULL, ARG_VERSION },
158 { "directory", required_argument, NULL, 'D' },
159 { "user", required_argument, NULL, 'u' },
160 { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK },
161 { "boot", no_argument, NULL, 'b' },
162 { "uuid", required_argument, NULL, ARG_UUID },
163 { "read-only", no_argument, NULL, ARG_READ_ONLY },
164 { "capability", required_argument, NULL, ARG_CAPABILITY },
165 { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
166 { "bind", required_argument, NULL, ARG_BIND },
167 { "bind-ro", required_argument, NULL, ARG_BIND_RO },
168 { "machine", required_argument, NULL, 'M' },
169 { "slice", required_argument, NULL, 'S' },
178 while ((c = getopt_long(argc, argv, "+hD:u:bM:jS:", options, NULL)) >= 0) {
187 puts(PACKAGE_STRING);
188 puts(SYSTEMD_FEATURES);
193 arg_directory = canonicalize_file_name(optarg);
194 if (!arg_directory) {
195 log_error("Failed to canonicalize root directory.");
203 arg_user = strdup(optarg);
209 case ARG_PRIVATE_NETWORK:
210 arg_private_network = true;
218 r = sd_id128_from_string(optarg, &arg_uuid);
220 log_error("Invalid UUID: %s", optarg);
226 arg_slice = strdup(optarg);
230 if (!hostname_is_valid(optarg)) {
231 log_error("Invalid machine name: %s", optarg);
236 arg_machine = strdup(optarg);
243 arg_read_only = true;
246 case ARG_CAPABILITY: {
250 FOREACH_WORD_SEPARATOR(word, length, optarg, ",", state) {
254 t = strndup(word, length);
258 if (cap_from_name(t, &cap) < 0) {
259 log_error("Failed to parse capability %s.", t);
265 arg_retain |= 1ULL << (uint64_t) cap;
272 arg_link_journal = LINK_GUEST;
275 case ARG_LINK_JOURNAL:
276 if (streq(optarg, "auto"))
277 arg_link_journal = LINK_AUTO;
278 else if (streq(optarg, "no"))
279 arg_link_journal = LINK_NO;
280 else if (streq(optarg, "guest"))
281 arg_link_journal = LINK_GUEST;
282 else if (streq(optarg, "host"))
283 arg_link_journal = LINK_HOST;
285 log_error("Failed to parse link journal mode %s", optarg);
293 _cleanup_free_ char *a = NULL, *b = NULL;
297 x = c == ARG_BIND ? &arg_bind : &arg_bind_ro;
299 e = strchr(optarg, ':');
301 a = strndup(optarg, e - optarg);
311 if (!path_is_absolute(a) || !path_is_absolute(b)) {
312 log_error("Invalid bind mount specification: %s", optarg);
316 r = strv_extend(x, a);
320 r = strv_extend(x, b);
331 log_error("Unknown option code %c", c);
339 static int mount_all(const char *dest) {
341 typedef struct MountPoint {
350 static const MountPoint mount_table[] = {
351 { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
352 { "/proc/sys", "/proc/sys", NULL, NULL, MS_BIND, true }, /* Bind mount first */
353 { NULL, "/proc/sys", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, true }, /* Then, make it r/o */
354 { "sysfs", "/sys", "sysfs", NULL, MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
355 { "tmpfs", "/dev", "tmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true },
356 { "devpts", "/dev/pts", "devpts","newinstance,ptmxmode=0666,mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, true },
357 { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
358 { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
360 { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL, MS_BIND, false }, /* Bind mount first */
361 { NULL, "/sys/fs/selinux", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, false }, /* Then, make it r/o */
368 for (k = 0; k < ELEMENTSOF(mount_table); k++) {
369 _cleanup_free_ char *where = NULL;
372 where = strjoin(dest, "/", mount_table[k].where, NULL);
376 t = path_is_mount_point(where, true);
378 log_error("Failed to detect whether %s is a mount point: %s", where, strerror(-t));
386 /* Skip this entry if it is not a remount. */
387 if (mount_table[k].what && t > 0)
390 mkdir_p(where, 0755);
392 if (mount(mount_table[k].what,
395 mount_table[k].flags,
396 mount_table[k].options) < 0 &&
397 mount_table[k].fatal) {
399 log_error("mount(%s) failed: %m", where);
409 static int mount_binds(const char *dest, char **l, unsigned long flags) {
412 STRV_FOREACH_PAIR(x, y, l) {
413 _cleanup_free_ char *where = NULL;
414 struct stat source_st, dest_st;
416 if (stat(*x, &source_st) < 0) {
417 log_error("failed to stat %s: %m", *x);
421 where = strjoin(dest, "/", *y, NULL);
425 if (stat(where, &dest_st) == 0) {
426 if ((source_st.st_mode & S_IFMT) != (dest_st.st_mode & S_IFMT)) {
427 log_error("The file types of %s and %s do not match. Refusing bind mount",
432 /* Create the mount point, but be conservative -- refuse to create block
433 * and char devices. */
434 if (S_ISDIR(source_st.st_mode))
435 mkdir_p_label(where, 0755);
436 else if (S_ISFIFO(source_st.st_mode))
438 else if (S_ISSOCK(source_st.st_mode))
439 mknod(where, 0644 | S_IFSOCK, 0);
440 else if (S_ISREG(source_st.st_mode))
443 log_error("Refusing to create mountpoint for file: %s", *x);
448 if (mount(*x, where, "bind", MS_BIND, NULL) < 0) {
449 log_error("mount(%s) failed: %m", where);
453 if (flags && mount(NULL, where, NULL, MS_REMOUNT|MS_BIND|flags, NULL) < 0) {
454 log_error("mount(%s) failed: %m", where);
462 static int setup_timezone(const char *dest) {
463 _cleanup_free_ char *where = NULL, *p = NULL, *q = NULL, *check = NULL, *what = NULL;
469 /* Fix the timezone, if possible */
470 r = readlink_malloc("/etc/localtime", &p);
472 log_warning("/etc/localtime is not a symlink, not updating container timezone.");
476 z = path_startswith(p, "../usr/share/zoneinfo/");
478 z = path_startswith(p, "/usr/share/zoneinfo/");
480 log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone.");
484 where = strappend(dest, "/etc/localtime");
488 r = readlink_malloc(where, &q);
490 y = path_startswith(q, "../usr/share/zoneinfo/");
492 y = path_startswith(q, "/usr/share/zoneinfo/");
495 /* Already pointing to the right place? Then do nothing .. */
496 if (y && streq(y, z))
500 check = strjoin(dest, "/usr/share/zoneinfo/", z, NULL);
504 if (access(check, F_OK) < 0) {
505 log_warning("Timezone %s does not exist in container, not updating container timezone.", z);
509 what = strappend("../usr/share/zoneinfo/", z);
514 if (symlink(what, where) < 0) {
515 log_error("Failed to correct timezone of container: %m");
522 static int setup_resolv_conf(const char *dest) {
523 char _cleanup_free_ *where = NULL;
527 if (arg_private_network)
530 /* Fix resolv.conf, if possible */
531 where = strappend(dest, "/etc/resolv.conf");
535 /* We don't really care for the results of this really. If it
536 * fails, it fails, but meh... */
537 copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW);
542 static int setup_boot_id(const char *dest) {
543 _cleanup_free_ char *from = NULL, *to = NULL;
550 /* Generate a new randomized boot ID, so that each boot-up of
551 * the container gets a new one */
553 from = strappend(dest, "/dev/proc-sys-kernel-random-boot-id");
554 to = strappend(dest, "/proc/sys/kernel/random/boot_id");
558 r = sd_id128_randomize(&rnd);
560 log_error("Failed to generate random boot id: %s", strerror(-r));
564 snprintf(as_uuid, sizeof(as_uuid),
565 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
566 SD_ID128_FORMAT_VAL(rnd));
567 char_array_0(as_uuid);
569 r = write_string_file(from, as_uuid);
571 log_error("Failed to write boot id: %s", strerror(-r));
575 if (mount(from, to, "bind", MS_BIND, NULL) < 0) {
576 log_error("Failed to bind mount boot id: %m");
578 } else if (mount(from, to, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL))
579 log_warning("Failed to make boot id read-only: %m");
585 static int copy_devnodes(const char *dest) {
587 static const char devnodes[] =
597 _cleanup_umask_ mode_t u;
603 NULSTR_FOREACH(d, devnodes) {
605 _cleanup_free_ char *from = NULL, *to = NULL;
607 asprintf(&from, "/dev/%s", d);
608 asprintf(&to, "%s/dev/%s", dest, d);
619 if (stat(from, &st) < 0) {
621 if (errno != ENOENT) {
622 log_error("Failed to stat %s: %m", from);
627 } else if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) {
629 log_error("%s is not a char or block device, cannot copy", from);
633 } else if (mknod(to, st.st_mode, st.st_rdev) < 0) {
635 log_error("mknod(%s) failed: %m", dest);
644 static int setup_ptmx(const char *dest) {
645 _cleanup_free_ char *p = NULL;
647 p = strappend(dest, "/dev/ptmx");
651 if (symlink("pts/ptmx", p) < 0) {
652 log_error("Failed to create /dev/ptmx symlink: %m");
659 static int setup_dev_console(const char *dest, const char *console) {
661 _cleanup_free_ char *to = NULL;
663 _cleanup_umask_ mode_t u;
670 if (stat(console, &st) < 0) {
671 log_error("Failed to stat %s: %m", console);
674 } else if (!S_ISCHR(st.st_mode)) {
675 log_error("/dev/console is not a char device");
679 r = chmod_and_chown(console, 0600, 0, 0);
681 log_error("Failed to correct access mode for TTY: %s", strerror(-r));
685 if (asprintf(&to, "%s/dev/console", dest) < 0)
688 /* We need to bind mount the right tty to /dev/console since
689 * ptys can only exist on pts file systems. To have something
690 * to bind mount things on we create a device node first, that
691 * has the right major/minor (note that the major minor
692 * doesn't actually matter here, since we mount it over
695 if (mknod(to, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0) {
696 log_error("mknod() for /dev/console failed: %m");
700 if (mount(console, to, "bind", MS_BIND, NULL) < 0) {
701 log_error("Bind mount for /dev/console failed: %m");
708 static int setup_kmsg(const char *dest, int kmsg_socket) {
709 _cleanup_free_ char *from = NULL, *to = NULL;
711 _cleanup_umask_ mode_t u;
713 struct cmsghdr cmsghdr;
714 uint8_t buf[CMSG_SPACE(sizeof(int))];
717 .msg_control = &control,
718 .msg_controllen = sizeof(control),
720 struct cmsghdr *cmsg;
723 assert(kmsg_socket >= 0);
727 /* We create the kmsg FIFO as /dev/kmsg, but immediately
728 * delete it after bind mounting it to /proc/kmsg. While FIFOs
729 * on the reading side behave very similar to /proc/kmsg,
730 * their writing side behaves differently from /dev/kmsg in
731 * that writing blocks when nothing is reading. In order to
732 * avoid any problems with containers deadlocking due to this
733 * we simply make /dev/kmsg unavailable to the container. */
734 if (asprintf(&from, "%s/dev/kmsg", dest) < 0 ||
735 asprintf(&to, "%s/proc/kmsg", dest) < 0)
738 if (mkfifo(from, 0600) < 0) {
739 log_error("mkfifo() for /dev/kmsg failed: %m");
743 r = chmod_and_chown(from, 0600, 0, 0);
745 log_error("Failed to correct access mode for /dev/kmsg: %s", strerror(-r));
749 if (mount(from, to, "bind", MS_BIND, NULL) < 0) {
750 log_error("Bind mount for /proc/kmsg failed: %m");
754 fd = open(from, O_RDWR|O_NDELAY|O_CLOEXEC);
756 log_error("Failed to open fifo: %m");
760 cmsg = CMSG_FIRSTHDR(&mh);
761 cmsg->cmsg_level = SOL_SOCKET;
762 cmsg->cmsg_type = SCM_RIGHTS;
763 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
764 memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
766 mh.msg_controllen = cmsg->cmsg_len;
768 /* Store away the fd in the socket, so that it stays open as
769 * long as we run the child */
770 k = sendmsg(kmsg_socket, &mh, MSG_DONTWAIT|MSG_NOSIGNAL);
771 close_nointr_nofail(fd);
774 log_error("Failed to send FIFO fd: %m");
778 /* And now make the FIFO unavailable as /dev/kmsg... */
783 static int setup_hostname(void) {
785 if (sethostname(arg_machine, strlen(arg_machine)) < 0)
791 static int setup_journal(const char *directory) {
792 sd_id128_t machine_id;
793 _cleanup_free_ char *p = NULL, *b = NULL, *q = NULL, *d = NULL;
797 if (arg_link_journal == LINK_NO)
800 p = strappend(directory, "/etc/machine-id");
804 r = read_one_line_file(p, &b);
805 if (r == -ENOENT && arg_link_journal == LINK_AUTO)
808 log_error("Failed to read machine ID from %s: %s", p, strerror(-r));
813 if (isempty(id) && arg_link_journal == LINK_AUTO)
816 /* Verify validity */
817 r = sd_id128_from_string(id, &machine_id);
819 log_error("Failed to parse machine ID from %s: %s", p, strerror(-r));
824 p = strappend("/var/log/journal/", id);
825 q = strjoin(directory, "/var/log/journal/", id, NULL);
829 if (path_is_mount_point(p, false) > 0) {
830 if (arg_link_journal != LINK_AUTO) {
831 log_error("%s: already a mount point, refusing to use for journal", p);
838 if (path_is_mount_point(q, false) > 0) {
839 if (arg_link_journal != LINK_AUTO) {
840 log_error("%s: already a mount point, refusing to use for journal", q);
847 r = readlink_and_make_absolute(p, &d);
849 if ((arg_link_journal == LINK_GUEST ||
850 arg_link_journal == LINK_AUTO) &&
853 r = mkdir_p(q, 0755);
855 log_warning("failed to create directory %s: %m", q);
860 log_error("Failed to remove symlink %s: %m", p);
863 } else if (r == -EINVAL) {
865 if (arg_link_journal == LINK_GUEST &&
868 if (errno == ENOTDIR) {
869 log_error("%s already exists and is neither a symlink nor a directory", p);
872 log_error("Failed to remove %s: %m", p);
876 } else if (r != -ENOENT) {
877 log_error("readlink(%s) failed: %m", p);
881 if (arg_link_journal == LINK_GUEST) {
883 if (symlink(q, p) < 0) {
884 log_error("Failed to symlink %s to %s: %m", q, p);
888 r = mkdir_p(q, 0755);
890 log_warning("failed to create directory %s: %m", q);
894 if (arg_link_journal == LINK_HOST) {
895 r = mkdir_p(p, 0755);
897 log_error("Failed to create %s: %m", p);
901 } else if (access(p, F_OK) < 0)
904 if (dir_is_empty(q) == 0) {
905 log_error("%s not empty.", q);
909 r = mkdir_p(q, 0755);
911 log_error("Failed to create %s: %m", q);
915 if (mount(p, q, "bind", MS_BIND, NULL) < 0) {
916 log_error("Failed to bind mount journal from host into guest: %m");
923 static int drop_capabilities(void) {
924 return capability_bounding_set_drop(~arg_retain, false);
927 static int register_machine(void) {
928 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
929 _cleanup_bus_unref_ sd_bus *bus = NULL;
932 r = sd_bus_open_system(&bus);
934 log_error("Failed to open system bus: %s", strerror(-r));
938 r = sd_bus_call_method(
940 "org.freedesktop.machine1",
941 "/org/freedesktop/machine1",
942 "org.freedesktop.machine1.Manager",
948 SD_BUS_MESSAGE_APPEND_ID128(arg_uuid),
952 strempty(arg_directory),
953 !isempty(arg_slice), "Slice", "s", arg_slice);
955 log_error("Failed to register machine: %s", error.message ? error.message : strerror(-r));
962 static bool audit_enabled(void) {
965 fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_AUDIT);
967 close_nointr_nofail(fd);
973 int main(int argc, char *argv[]) {
975 int r = EXIT_FAILURE, k;
976 _cleanup_close_ int master = -1;
978 const char *console = NULL;
979 struct termios saved_attr, raw_attr;
981 bool saved_attr_valid = false;
983 int kmsg_socket_pair[2] = { -1, -1 };
984 _cleanup_fdset_free_ FDSet *fds = NULL;
986 log_parse_environment();
989 k = parse_argv(argc, argv);
1000 p = path_make_absolute_cwd(arg_directory);
1001 free(arg_directory);
1004 arg_directory = get_current_dir_name();
1006 if (!arg_directory) {
1007 log_error("Failed to determine path, please use -D.");
1011 path_kill_slashes(arg_directory);
1014 arg_machine = strdup(path_get_file_name(arg_directory));
1020 hostname_cleanup(arg_machine, false);
1021 if (isempty(arg_machine)) {
1022 log_error("Failed to determine machine name automatically, please use -M.");
1027 if (geteuid() != 0) {
1028 log_error("Need to be root.");
1032 if (sd_booted() <= 0) {
1033 log_error("Not running on a systemd system.");
1037 if (arg_boot && audit_enabled()) {
1038 log_warning("The kernel auditing subsystem is known to be incompatible with containers.\n"
1039 "Please make sure to turn off auditing with 'audit=0' on the kernel command\n"
1040 "line before using systemd-nspawn. Sleeping for 5s...\n");
1044 if (path_equal(arg_directory, "/")) {
1045 log_error("Spawning container on root directory not supported.");
1049 if (path_is_os_tree(arg_directory) <= 0) {
1050 log_error("Directory %s doesn't look like an OS root directory (/etc/os-release is missing). Refusing.", arg_directory);
1055 n_fd_passed = sd_listen_fds(false);
1056 if (n_fd_passed > 0) {
1057 k = fdset_new_listen_fds(&fds, false);
1059 log_error("Failed to collect file descriptors: %s", strerror(-k));
1063 fdset_close_others(fds);
1066 master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY);
1068 log_error("Failed to acquire pseudo tty: %m");
1072 console = ptsname(master);
1074 log_error("Failed to determine tty name: %m");
1078 log_info("Spawning namespace container on %s (console is %s).", arg_directory, console);
1080 if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
1081 ioctl(master, TIOCSWINSZ, &ws);
1083 if (unlockpt(master) < 0) {
1084 log_error("Failed to unlock tty: %m");
1088 if (tcgetattr(STDIN_FILENO, &saved_attr) >= 0) {
1089 saved_attr_valid = true;
1091 raw_attr = saved_attr;
1092 cfmakeraw(&raw_attr);
1093 raw_attr.c_lflag &= ~ECHO;
1096 if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
1097 log_error("Failed to create kmsg socket pair.");
1101 sd_notify(0, "READY=1");
1103 assert_se(sigemptyset(&mask) == 0);
1104 sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1);
1105 assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0);
1109 int pipefd[2], pipefd2[2];
1111 if (pipe2(pipefd, O_NONBLOCK|O_CLOEXEC) < 0) {
1112 log_error("pipe2(): %m");
1116 if (pipe2(pipefd2, O_NONBLOCK|O_CLOEXEC) < 0) {
1117 log_error("pipe2(): %m");
1122 pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS|(arg_private_network ? CLONE_NEWNET : 0), NULL);
1124 if (errno == EINVAL)
1125 log_error("clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m");
1127 log_error("clone() failed: %m");
1134 const char *home = NULL;
1135 uid_t uid = (uid_t) -1;
1136 gid_t gid = (gid_t) -1;
1138 const char *envp[] = {
1139 "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
1140 "container=systemd-nspawn", /* LXC sets container=lxc, so follow the scheme here */
1145 NULL, /* container_uuid */
1146 NULL, /* LISTEN_FDS */
1147 NULL, /* LISTEN_PID */
1151 envp[n_env] = strv_find_prefix(environ, "TERM=");
1155 /* Wait for the parent process to log our PID */
1156 close_nointr_nofail(pipefd[1]);
1157 fd_wait_for_event(pipefd[0], POLLHUP, -1);
1158 close_nointr_nofail(pipefd[0]);
1160 close_nointr_nofail(master);
1163 if (saved_attr_valid) {
1164 if (tcsetattr(STDIN_FILENO, TCSANOW, &raw_attr) < 0) {
1165 log_error("Failed to set terminal attributes: %m");
1170 close_nointr(STDIN_FILENO);
1171 close_nointr(STDOUT_FILENO);
1172 close_nointr(STDERR_FILENO);
1174 close_nointr_nofail(kmsg_socket_pair[0]);
1175 kmsg_socket_pair[0] = -1;
1177 reset_all_signal_handlers();
1179 assert_se(sigemptyset(&mask) == 0);
1180 assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
1182 k = open_terminal(console, O_RDWR);
1183 if (k != STDIN_FILENO) {
1185 close_nointr_nofail(k);
1189 log_error("Failed to open console: %s", strerror(-k));
1193 if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
1194 dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
1195 log_error("Failed to duplicate console: %m");
1200 log_error("setsid() failed: %m");
1204 if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) {
1205 log_error("PR_SET_PDEATHSIG failed: %m");
1209 close_pipe(pipefd2);
1211 r = register_machine();
1215 /* Mark everything as slave, so that we still
1216 * receive mounts from the real root, but don't
1217 * propagate mounts to the real root. */
1218 if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
1219 log_error("MS_SLAVE|MS_REC failed: %m");
1223 /* Turn directory into bind mount */
1224 if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REC, NULL) < 0) {
1225 log_error("Failed to make bind mount.");
1230 if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY|MS_REC, NULL) < 0) {
1231 log_error("Failed to make read-only.");
1235 if (mount_all(arg_directory) < 0)
1238 if (copy_devnodes(arg_directory) < 0)
1241 if (setup_ptmx(arg_directory) < 0)
1244 dev_setup(arg_directory);
1246 if (setup_dev_console(arg_directory, console) < 0)
1249 if (setup_kmsg(arg_directory, kmsg_socket_pair[1]) < 0)
1252 close_nointr_nofail(kmsg_socket_pair[1]);
1253 kmsg_socket_pair[1] = -1;
1255 if (setup_boot_id(arg_directory) < 0)
1258 if (setup_timezone(arg_directory) < 0)
1261 if (setup_resolv_conf(arg_directory) < 0)
1264 if (setup_journal(arg_directory) < 0)
1267 if (mount_binds(arg_directory, arg_bind, 0) < 0)
1270 if (mount_binds(arg_directory, arg_bind_ro, MS_RDONLY) < 0)
1273 if (chdir(arg_directory) < 0) {
1274 log_error("chdir(%s) failed: %m", arg_directory);
1278 if (mount(arg_directory, "/", NULL, MS_MOVE, NULL) < 0) {
1279 log_error("mount(MS_MOVE) failed: %m");
1283 if (chroot(".") < 0) {
1284 log_error("chroot() failed: %m");
1288 if (chdir("/") < 0) {
1289 log_error("chdir() failed: %m");
1297 if (drop_capabilities() < 0) {
1298 log_error("drop_capabilities() failed: %m");
1304 /* Note that this resolves user names
1305 * inside the container, and hence
1306 * accesses the NSS modules from the
1307 * container and not the host. This is
1310 if (get_user_creds((const char**)&arg_user, &uid, &gid, &home, NULL) < 0) {
1311 log_error("get_user_creds() failed: %m");
1315 if (mkdir_parents_label(home, 0775) < 0) {
1316 log_error("mkdir_parents_label() failed: %m");
1320 if (mkdir_safe_label(home, 0775, uid, gid) < 0) {
1321 log_error("mkdir_safe_label() failed: %m");
1325 if (initgroups((const char*)arg_user, gid) < 0) {
1326 log_error("initgroups() failed: %m");
1330 if (setresgid(gid, gid, gid) < 0) {
1331 log_error("setregid() failed: %m");
1335 if (setresuid(uid, uid, uid) < 0) {
1336 log_error("setreuid() failed: %m");
1340 /* Reset everything fully to 0, just in case */
1342 if (setgroups(0, NULL) < 0) {
1343 log_error("setgroups() failed: %m");
1347 if (setresgid(0, 0, 0) < 0) {
1348 log_error("setregid() failed: %m");
1352 if (setresuid(0, 0, 0) < 0) {
1353 log_error("setreuid() failed: %m");
1358 if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) ||
1359 (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) ||
1360 (asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) {
1365 if (!sd_id128_equal(arg_uuid, SD_ID128_NULL)) {
1366 if (asprintf((char**)(envp + n_env++), "container_uuid=" SD_ID128_FORMAT_STR, SD_ID128_FORMAT_VAL(arg_uuid)) < 0) {
1372 if (fdset_size(fds) > 0) {
1373 k = fdset_cloexec(fds, false);
1375 log_error("Failed to unset O_CLOEXEC for file descriptors.");
1379 if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) ||
1380 (asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0)) {
1392 /* Automatically search for the init system */
1394 l = 1 + argc - optind;
1395 a = newa(char*, l + 1);
1396 memcpy(a + 1, argv + optind, l * sizeof(char*));
1398 a[0] = (char*) "/usr/lib/systemd/systemd";
1399 execve(a[0], a, (char**) envp);
1401 a[0] = (char*) "/lib/systemd/systemd";
1402 execve(a[0], a, (char**) envp);
1404 a[0] = (char*) "/sbin/init";
1405 execve(a[0], a, (char**) envp);
1406 } else if (argc > optind)
1407 execvpe(argv[optind], argv + optind, (char**) envp);
1409 chdir(home ? home : "/root");
1410 execle("/bin/bash", "-bash", NULL, (char**) envp);
1413 log_error("execv() failed: %m");
1416 _exit(EXIT_FAILURE);
1419 log_info("Init process in the container running as PID %lu.", (unsigned long) pid);
1420 close_nointr_nofail(pipefd[0]);
1421 close_nointr_nofail(pipefd[1]);
1423 /* Wait for the child process to establish cgroup hierarchy */
1424 close_nointr_nofail(pipefd2[1]);
1425 fd_wait_for_event(pipefd2[0], POLLHUP, -1);
1426 close_nointr_nofail(pipefd2[0]);
1431 if (process_pty(master, &mask, arg_boot ? pid : 0, SIGRTMIN+3) < 0)
1434 if (saved_attr_valid)
1435 tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
1437 k = wait_for_terminate(pid, &status);
1443 if (status.si_code == CLD_EXITED) {
1444 r = status.si_status;
1445 if (status.si_status != 0) {
1446 log_error("Container failed with error code %i.", status.si_status);
1450 log_debug("Container exited successfully.");
1452 } else if (status.si_code == CLD_KILLED &&
1453 status.si_status == SIGINT) {
1454 log_info("Container has been shut down.");
1457 } else if (status.si_code == CLD_KILLED &&
1458 status.si_status == SIGHUP) {
1459 log_info("Container is being rebooted.");
1461 } else if (status.si_code == CLD_KILLED ||
1462 status.si_code == CLD_DUMPED) {
1464 log_error("Container terminated by signal %s.", signal_to_string(status.si_status));
1468 log_error("Container failed due to unknown reason.");
1475 if (saved_attr_valid)
1476 tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
1478 close_pipe(kmsg_socket_pair);
1483 free(arg_directory);