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authorEvgeny Vereshchagin <evvers@ya.ru>2016-10-10 20:47:25 +0300
committerGitHub <noreply@github.com>2016-10-10 20:47:25 +0300
commita0f72a24e0b3454034a87d8a4a4bfd36c34f1d49 (patch)
treebaf791be9d8794ad0b1153f6ad45d78d974e6f9f /src/nspawn/nspawn.c
parentbaed1fedba161d7db89636a417751891831c432a (diff)
parenta8725a06e6c5073325f2f6a7d6ef115c11d30a51 (diff)
Merge pull request #4310 from keszybz/nspawn-autodetect
Autodetect systemd version in containers started by systemd-nspawn
Diffstat (limited to 'src/nspawn/nspawn.c')
-rw-r--r--src/nspawn/nspawn.c943
1 files changed, 466 insertions, 477 deletions
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index d29866c3fe..e066c55dae 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -316,17 +316,10 @@ static int custom_mounts_prepare(void) {
return 0;
}
-static int detect_unified_cgroup_hierarchy(void) {
+static int detect_unified_cgroup_hierarchy(const char *directory) {
const char *e;
int r, all_unified, systemd_unified;
- all_unified = cg_all_unified();
- systemd_unified = cg_unified(SYSTEMD_CGROUP_CONTROLLER);
-
- if (all_unified < 0 || systemd_unified < 0)
- return log_error_errno(all_unified < 0 ? all_unified : systemd_unified,
- "Failed to determine whether the unified cgroups hierarchy is used: %m");
-
/* Allow the user to control whether the unified hierarchy is used */
e = getenv("UNIFIED_CGROUP_HIERARCHY");
if (e) {
@@ -341,12 +334,34 @@ static int detect_unified_cgroup_hierarchy(void) {
return 0;
}
+ all_unified = cg_all_unified();
+ systemd_unified = cg_unified(SYSTEMD_CGROUP_CONTROLLER);
+
+ if (all_unified < 0 || systemd_unified < 0)
+ return log_error_errno(all_unified < 0 ? all_unified : systemd_unified,
+ "Failed to determine whether the unified cgroups hierarchy is used: %m");
+
/* Otherwise inherit the default from the host system */
- if (all_unified > 0)
- arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
- else if (systemd_unified > 0)
- arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_SYSTEMD;
- else
+ if (all_unified > 0) {
+ /* Unified cgroup hierarchy support was added in 230. Unfortunately the detection
+ * routine only detects 231, so we'll have a false negative here for 230. */
+ r = systemd_installation_has_version(directory, 230);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine systemd version in container: %m");
+ if (r > 0)
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
+ else
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
+ } else if (systemd_unified > 0) {
+ /* Mixed cgroup hierarchy support was added in 232 */
+ r = systemd_installation_has_version(directory, 232);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine systemd version in container: %m");
+ if (r > 0)
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_SYSTEMD;
+ else
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
+ } else
arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
return 0;
@@ -1121,10 +1136,6 @@ static int parse_argv(int argc, char *argv[]) {
arg_caps_retain = (arg_caps_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus;
- r = detect_unified_cgroup_hierarchy();
- if (r < 0)
- return r;
-
e = getenv("SYSTEMD_NSPAWN_CONTAINER_SERVICE");
if (e)
arg_container_service_name = e;
@@ -2966,6 +2977,10 @@ static int outer_child(
if (r < 0)
return r;
+ r = detect_unified_cgroup_hierarchy(directory);
+ if (r < 0)
+ return r;
+
if (arg_userns_mode != USER_NAMESPACE_NO) {
/* Let the parent know which UID shift we read from the image */
l = send(uid_shift_socket, &arg_uid_shift, sizeof(arg_uid_shift), MSG_NOSIGNAL);
@@ -3571,18 +3586,437 @@ static int load_settings(void) {
return 0;
}
+static int run(int master,
+ const char* console,
+ const char *root_device, bool root_device_rw,
+ const char *home_device, bool home_device_rw,
+ const char *srv_device, bool srv_device_rw,
+ const char *esp_device,
+ bool interactive,
+ bool secondary,
+ FDSet *fds,
+ char veth_name[IFNAMSIZ], bool *veth_created,
+ union in_addr_union *exposed,
+ pid_t *pid, int *ret) {
+
+ static const struct sigaction sa = {
+ .sa_handler = nop_signal_handler,
+ .sa_flags = SA_NOCLDSTOP,
+ };
+
+ _cleanup_release_lock_file_ LockFile uid_shift_lock = LOCK_FILE_INIT;
+ _cleanup_close_ int etc_passwd_lock = -1;
+ _cleanup_close_pair_ int
+ kmsg_socket_pair[2] = { -1, -1 },
+ rtnl_socket_pair[2] = { -1, -1 },
+ pid_socket_pair[2] = { -1, -1 },
+ uuid_socket_pair[2] = { -1, -1 },
+ notify_socket_pair[2] = { -1, -1 },
+ uid_shift_socket_pair[2] = { -1, -1 };
+ _cleanup_close_ int notify_socket= -1;
+ _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
+ _cleanup_(sd_event_unrefp) sd_event *event = NULL;
+ _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
+ _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
+ ContainerStatus container_status = 0;
+ char last_char = 0;
+ int ifi = 0, r;
+ ssize_t l;
+ sigset_t mask_chld;
+
+ assert_se(sigemptyset(&mask_chld) == 0);
+ assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
+
+ if (arg_userns_mode == USER_NAMESPACE_PICK) {
+ /* When we shall pick the UID/GID range, let's first lock /etc/passwd, so that we can safely
+ * check with getpwuid() if the specific user already exists. Note that /etc might be
+ * read-only, in which case this will fail with EROFS. But that's really OK, as in that case we
+ * can be reasonably sure that no users are going to be added. Note that getpwuid() checks are
+ * really just an extra safety net. We kinda assume that the UID range we allocate from is
+ * really ours. */
+
+ etc_passwd_lock = take_etc_passwd_lock(NULL);
+ if (etc_passwd_lock < 0 && etc_passwd_lock != -EROFS)
+ return log_error_errno(etc_passwd_lock, "Failed to take /etc/passwd lock: %m");
+ }
+
+ r = barrier_create(&barrier);
+ if (r < 0)
+ return log_error_errno(r, "Cannot initialize IPC barrier: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create kmsg socket pair: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, rtnl_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create rtnl socket pair: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pid_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create pid socket pair: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uuid_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create id socket pair: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, notify_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create notify socket pair: %m");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO)
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uid_shift_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create uid shift socket pair: %m");
+
+ /* Child can be killed before execv(), so handle SIGCHLD in order to interrupt
+ * parent's blocking calls and give it a chance to call wait() and terminate. */
+ r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to change the signal mask: %m");
+
+ r = sigaction(SIGCHLD, &sa, NULL);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to install SIGCHLD handler: %m");
+
+ *pid = raw_clone(SIGCHLD|CLONE_NEWNS);
+ if (*pid < 0)
+ return log_error_errno(errno, "clone() failed%s: %m",
+ errno == EINVAL ?
+ ", do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in)" : "");
+
+ if (*pid == 0) {
+ /* The outer child only has a file system namespace. */
+ barrier_set_role(&barrier, BARRIER_CHILD);
+
+ master = safe_close(master);
+
+ kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]);
+ rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
+ pid_socket_pair[0] = safe_close(pid_socket_pair[0]);
+ uuid_socket_pair[0] = safe_close(uuid_socket_pair[0]);
+ notify_socket_pair[0] = safe_close(notify_socket_pair[0]);
+ uid_shift_socket_pair[0] = safe_close(uid_shift_socket_pair[0]);
+
+ (void) reset_all_signal_handlers();
+ (void) reset_signal_mask();
+
+ r = outer_child(&barrier,
+ arg_directory,
+ console,
+ root_device, root_device_rw,
+ home_device, home_device_rw,
+ srv_device, srv_device_rw,
+ esp_device,
+ interactive,
+ secondary,
+ pid_socket_pair[1],
+ uuid_socket_pair[1],
+ notify_socket_pair[1],
+ kmsg_socket_pair[1],
+ rtnl_socket_pair[1],
+ uid_shift_socket_pair[1],
+ fds);
+ if (r < 0)
+ _exit(EXIT_FAILURE);
+
+ _exit(EXIT_SUCCESS);
+ }
+
+ barrier_set_role(&barrier, BARRIER_PARENT);
+
+ fds = fdset_free(fds);
+
+ kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
+ rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]);
+ pid_socket_pair[1] = safe_close(pid_socket_pair[1]);
+ uuid_socket_pair[1] = safe_close(uuid_socket_pair[1]);
+ notify_socket_pair[1] = safe_close(notify_socket_pair[1]);
+ uid_shift_socket_pair[1] = safe_close(uid_shift_socket_pair[1]);
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ /* The child just let us know the UID shift it might have read from the image. */
+ l = recv(uid_shift_socket_pair[0], &arg_uid_shift, sizeof arg_uid_shift, 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to read UID shift: %m");
+
+ if (l != sizeof arg_uid_shift) {
+ log_error("Short read while reading UID shift.");
+ return -EIO;
+ }
+
+ if (arg_userns_mode == USER_NAMESPACE_PICK) {
+ /* If we are supposed to pick the UID shift, let's try to use the shift read from the
+ * image, but if that's already in use, pick a new one, and report back to the child,
+ * which one we now picked. */
+
+ r = uid_shift_pick(&arg_uid_shift, &uid_shift_lock);
+ if (r < 0)
+ return log_error_errno(r, "Failed to pick suitable UID/GID range: %m");
+
+ l = send(uid_shift_socket_pair[0], &arg_uid_shift, sizeof arg_uid_shift, MSG_NOSIGNAL);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to send UID shift: %m");
+ if (l != sizeof arg_uid_shift) {
+ log_error("Short write while writing UID shift.");
+ return -EIO;
+ }
+ }
+ }
+
+ /* Wait for the outer child. */
+ r = wait_for_terminate_and_warn("namespace helper", *pid, NULL);
+ if (r != 0)
+ return r < 0 ? r : -EIO;
+
+ /* And now retrieve the PID of the inner child. */
+ l = recv(pid_socket_pair[0], pid, sizeof *pid, 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to read inner child PID: %m");
+ if (l != sizeof *pid) {
+ log_error("Short read while reading inner child PID.");
+ return -EIO;
+ }
+
+ /* We also retrieve container UUID in case it was generated by outer child */
+ l = recv(uuid_socket_pair[0], &arg_uuid, sizeof arg_uuid, 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to read container machine ID: %m");
+ if (l != sizeof(arg_uuid)) {
+ log_error("Short read while reading container machined ID.");
+ return -EIO;
+ }
+
+ /* We also retrieve the socket used for notifications generated by outer child */
+ notify_socket = receive_one_fd(notify_socket_pair[0], 0);
+ if (notify_socket < 0)
+ return log_error_errno(notify_socket,
+ "Failed to receive notification socket from the outer child: %m");
+
+ log_debug("Init process invoked as PID "PID_FMT, *pid);
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ if (!barrier_place_and_sync(&barrier)) { /* #1 */
+ log_error("Child died too early.");
+ return -ESRCH;
+ }
+
+ r = setup_uid_map(*pid);
+ if (r < 0)
+ return r;
+
+ (void) barrier_place(&barrier); /* #2 */
+ }
+
+ if (arg_private_network) {
+
+ r = move_network_interfaces(*pid, arg_network_interfaces);
+ if (r < 0)
+ return r;
+
+ if (arg_network_veth) {
+ r = setup_veth(arg_machine, *pid, veth_name,
+ arg_network_bridge || arg_network_zone);
+ if (r < 0)
+ return r;
+ else if (r > 0)
+ ifi = r;
+
+ if (arg_network_bridge) {
+ /* Add the interface to a bridge */
+ r = setup_bridge(veth_name, arg_network_bridge, false);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ ifi = r;
+ } else if (arg_network_zone) {
+ /* Add the interface to a bridge, possibly creating it */
+ r = setup_bridge(veth_name, arg_network_zone, true);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ ifi = r;
+ }
+ }
+
+ r = setup_veth_extra(arg_machine, *pid, arg_network_veth_extra);
+ if (r < 0)
+ return r;
+
+ /* We created the primary and extra veth links now; let's remember this, so that we know to
+ remove them later on. Note that we don't bother with removing veth links that were created
+ here when their setup failed half-way, because in that case the kernel should be able to
+ remove them on its own, since they cannot be referenced by anything yet. */
+ *veth_created = true;
+
+ r = setup_macvlan(arg_machine, *pid, arg_network_macvlan);
+ if (r < 0)
+ return r;
+
+ r = setup_ipvlan(arg_machine, *pid, arg_network_ipvlan);
+ if (r < 0)
+ return r;
+ }
+
+ if (arg_register) {
+ r = register_machine(
+ arg_machine,
+ *pid,
+ arg_directory,
+ arg_uuid,
+ ifi,
+ arg_slice,
+ arg_custom_mounts, arg_n_custom_mounts,
+ arg_kill_signal,
+ arg_property,
+ arg_keep_unit,
+ arg_container_service_name);
+ if (r < 0)
+ return r;
+ }
+
+ r = sync_cgroup(*pid, arg_unified_cgroup_hierarchy);
+ if (r < 0)
+ return r;
+
+ if (arg_keep_unit) {
+ r = create_subcgroup(*pid, arg_unified_cgroup_hierarchy);
+ if (r < 0)
+ return r;
+ }
+
+ r = chown_cgroup(*pid, arg_uid_shift);
+ if (r < 0)
+ return r;
+
+ /* Notify the child that the parent is ready with all
+ * its setup (including cgroup-ification), and that
+ * the child can now hand over control to the code to
+ * run inside the container. */
+ (void) barrier_place(&barrier); /* #3 */
+
+ /* Block SIGCHLD here, before notifying child.
+ * process_pty() will handle it with the other signals. */
+ assert_se(sigprocmask(SIG_BLOCK, &mask_chld, NULL) >= 0);
+
+ /* Reset signal to default */
+ r = default_signals(SIGCHLD, -1);
+ if (r < 0)
+ return log_error_errno(r, "Failed to reset SIGCHLD: %m");
+
+ r = sd_event_new(&event);
+ if (r < 0)
+ return log_error_errno(r, "Failed to get default event source: %m");
+
+ r = setup_sd_notify_parent(event, notify_socket, PID_TO_PTR(*pid));
+ if (r < 0)
+ return r;
+
+ /* Let the child know that we are ready and wait that the child is completely ready now. */
+ if (!barrier_place_and_sync(&barrier)) { /* #4 */
+ log_error("Child died too early.");
+ return -ESRCH;
+ }
+
+ /* At this point we have made use of the UID we picked, and thus nss-mymachines
+ * will make them appear in getpwuid(), thus we can release the /etc/passwd lock. */
+ etc_passwd_lock = safe_close(etc_passwd_lock);
+
+ sd_notifyf(false,
+ "STATUS=Container running.\n"
+ "X_NSPAWN_LEADER_PID=" PID_FMT, *pid);
+ if (!arg_notify_ready)
+ sd_notify(false, "READY=1\n");
+
+ if (arg_kill_signal > 0) {
+ /* Try to kill the init system on SIGINT or SIGTERM */
+ sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(*pid));
+ sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(*pid));
+ } else {
+ /* Immediately exit */
+ sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+ sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
+ }
+
+ /* simply exit on sigchld */
+ sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
+
+ if (arg_expose_ports) {
+ r = expose_port_watch_rtnl(event, rtnl_socket_pair[0], on_address_change, exposed, &rtnl);
+ if (r < 0)
+ return r;
+
+ (void) expose_port_execute(rtnl, arg_expose_ports, exposed);
+ }
+
+ rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
+
+ r = pty_forward_new(event, master,
+ PTY_FORWARD_IGNORE_VHANGUP | (interactive ? 0 : PTY_FORWARD_READ_ONLY),
+ &forward);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create PTY forwarder: %m");
+
+ r = sd_event_loop(event);
+ if (r < 0)
+ return log_error_errno(r, "Failed to run event loop: %m");
+
+ pty_forward_get_last_char(forward, &last_char);
+
+ forward = pty_forward_free(forward);
+
+ if (!arg_quiet && last_char != '\n')
+ putc('\n', stdout);
+
+ /* Kill if it is not dead yet anyway */
+ if (arg_register && !arg_keep_unit)
+ terminate_machine(*pid);
+
+ /* Normally redundant, but better safe than sorry */
+ kill(*pid, SIGKILL);
+
+ r = wait_for_container(*pid, &container_status);
+ *pid = 0;
+
+ if (r < 0)
+ /* We failed to wait for the container, or the container exited abnormally. */
+ return r;
+ if (r > 0 || container_status == CONTAINER_TERMINATED) {
+ /* r > 0 → The container exited with a non-zero status.
+ * As a special case, we need to replace 133 with a different value,
+ * because 133 is special-cased in the service file to reboot the container.
+ * otherwise → The container exited with zero status and a reboot was not requested.
+ */
+ if (r == 133)
+ r = EXIT_FAILURE; /* replace 133 with the general failure code */
+ *ret = r;
+ return 0; /* finito */
+ }
+
+ /* CONTAINER_REBOOTED, loop again */
+
+ if (arg_keep_unit) {
+ /* Special handling if we are running as a service: instead of simply
+ * restarting the machine we want to restart the entire service, so let's
+ * inform systemd about this with the special exit code 133. The service
+ * file uses RestartForceExitStatus=133 so that this results in a full
+ * nspawn restart. This is necessary since we might have cgroup parameters
+ * set we want to have flushed out. */
+ *ret = 0;
+ return 133;
+ }
+
+ expose_port_flush(arg_expose_ports, exposed);
+
+ (void) remove_veth_links(veth_name, arg_network_veth_extra);
+ *veth_created = false;
+ return 1; /* loop again */
+}
+
int main(int argc, char *argv[]) {
_cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL, *esp_device = NULL, *console = NULL;
bool root_device_rw = true, home_device_rw = true, srv_device_rw = true;
_cleanup_close_ int master = -1, image_fd = -1;
_cleanup_fdset_free_ FDSet *fds = NULL;
- int r, n_fd_passed, loop_nr = -1;
+ int r, n_fd_passed, loop_nr = -1, ret = EXIT_FAILURE;
char veth_name[IFNAMSIZ] = "";
bool secondary = false, remove_subvol = false;
- sigset_t mask_chld;
pid_t pid = 0;
- int ret = EXIT_SUCCESS;
union in_addr_union exposed = {};
_cleanup_release_lock_file_ LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT;
bool interactive, veth_created = false;
@@ -3798,470 +4232,25 @@ int main(int argc, char *argv[]) {
assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1) >= 0);
- assert_se(sigemptyset(&mask_chld) == 0);
- assert_se(sigaddset(&mask_chld, SIGCHLD) == 0);
-
if (prctl(PR_SET_CHILD_SUBREAPER, 1) < 0) {
r = log_error_errno(errno, "Failed to become subreaper: %m");
goto finish;
}
for (;;) {
- static const struct sigaction sa = {
- .sa_handler = nop_signal_handler,
- .sa_flags = SA_NOCLDSTOP,
- };
-
- _cleanup_release_lock_file_ LockFile uid_shift_lock = LOCK_FILE_INIT;
- _cleanup_close_ int etc_passwd_lock = -1;
- _cleanup_close_pair_ int
- kmsg_socket_pair[2] = { -1, -1 },
- rtnl_socket_pair[2] = { -1, -1 },
- pid_socket_pair[2] = { -1, -1 },
- uuid_socket_pair[2] = { -1, -1 },
- notify_socket_pair[2] = { -1, -1 },
- uid_shift_socket_pair[2] = { -1, -1 };
- _cleanup_close_ int notify_socket= -1;
- _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
- _cleanup_(sd_event_unrefp) sd_event *event = NULL;
- _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
- _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
- ContainerStatus container_status = 0;
- char last_char = 0;
- int ifi = 0;
- ssize_t l;
-
- if (arg_userns_mode == USER_NAMESPACE_PICK) {
- /* When we shall pick the UID/GID range, let's first lock /etc/passwd, so that we can safely
- * check with getpwuid() if the specific user already exists. Note that /etc might be
- * read-only, in which case this will fail with EROFS. But that's really OK, as in that case we
- * can be reasonably sure that no users are going to be added. Note that getpwuid() checks are
- * really just an extra safety net. We kinda assume that the UID range we allocate from is
- * really ours. */
-
- etc_passwd_lock = take_etc_passwd_lock(NULL);
- if (etc_passwd_lock < 0 && etc_passwd_lock != -EROFS) {
- log_error_errno(r, "Failed to take /etc/passwd lock: %m");
- goto finish;
- }
- }
-
- r = barrier_create(&barrier);
- if (r < 0) {
- log_error_errno(r, "Cannot initialize IPC barrier: %m");
- goto finish;
- }
-
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create kmsg socket pair: %m");
- goto finish;
- }
-
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, rtnl_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create rtnl socket pair: %m");
- goto finish;
- }
-
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pid_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create pid socket pair: %m");
- goto finish;
- }
-
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uuid_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create id socket pair: %m");
- goto finish;
- }
-
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, notify_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create notify socket pair: %m");
- goto finish;
- }
-
- if (arg_userns_mode != USER_NAMESPACE_NO)
- if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uid_shift_socket_pair) < 0) {
- r = log_error_errno(errno, "Failed to create uid shift socket pair: %m");
- goto finish;
- }
-
- /* Child can be killed before execv(), so handle SIGCHLD
- * in order to interrupt parent's blocking calls and
- * give it a chance to call wait() and terminate. */
- r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL);
- if (r < 0) {
- r = log_error_errno(errno, "Failed to change the signal mask: %m");
- goto finish;
- }
-
- r = sigaction(SIGCHLD, &sa, NULL);
- if (r < 0) {
- r = log_error_errno(errno, "Failed to install SIGCHLD handler: %m");
- goto finish;
- }
-
- pid = raw_clone(SIGCHLD|CLONE_NEWNS);
- if (pid < 0) {
- if (errno == EINVAL)
- r = 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");
- else
- r = log_error_errno(errno, "clone() failed: %m");
-
- goto finish;
- }
-
- if (pid == 0) {
- /* The outer child only has a file system namespace. */
- barrier_set_role(&barrier, BARRIER_CHILD);
-
- master = safe_close(master);
-
- kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]);
- rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
- pid_socket_pair[0] = safe_close(pid_socket_pair[0]);
- uuid_socket_pair[0] = safe_close(uuid_socket_pair[0]);
- notify_socket_pair[0] = safe_close(notify_socket_pair[0]);
- uid_shift_socket_pair[0] = safe_close(uid_shift_socket_pair[0]);
-
- (void) reset_all_signal_handlers();
- (void) reset_signal_mask();
-
- r = outer_child(&barrier,
- arg_directory,
- console,
- root_device, root_device_rw,
- home_device, home_device_rw,
- srv_device, srv_device_rw,
- esp_device,
- interactive,
- secondary,
- pid_socket_pair[1],
- uuid_socket_pair[1],
- notify_socket_pair[1],
- kmsg_socket_pair[1],
- rtnl_socket_pair[1],
- uid_shift_socket_pair[1],
- fds);
- if (r < 0)
- _exit(EXIT_FAILURE);
-
- _exit(EXIT_SUCCESS);
- }
-
- barrier_set_role(&barrier, BARRIER_PARENT);
-
- fds = fdset_free(fds);
-
- kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]);
- rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]);
- pid_socket_pair[1] = safe_close(pid_socket_pair[1]);
- uuid_socket_pair[1] = safe_close(uuid_socket_pair[1]);
- notify_socket_pair[1] = safe_close(notify_socket_pair[1]);
- uid_shift_socket_pair[1] = safe_close(uid_shift_socket_pair[1]);
-
- if (arg_userns_mode != USER_NAMESPACE_NO) {
- /* The child just let us know the UID shift it might have read from the image. */
- l = recv(uid_shift_socket_pair[0], &arg_uid_shift, sizeof(arg_uid_shift), 0);
- if (l < 0) {
- r = log_error_errno(errno, "Failed to read UID shift: %m");
- goto finish;
- }
- if (l != sizeof(arg_uid_shift)) {
- log_error("Short read while reading UID shift.");
- r = EIO;
- goto finish;
- }
-
- if (arg_userns_mode == USER_NAMESPACE_PICK) {
- /* If we are supposed to pick the UID shift, let's try to use the shift read from the
- * image, but if that's already in use, pick a new one, and report back to the child,
- * which one we now picked. */
-
- r = uid_shift_pick(&arg_uid_shift, &uid_shift_lock);
- if (r < 0) {
- log_error_errno(r, "Failed to pick suitable UID/GID range: %m");
- goto finish;
- }
-
- l = send(uid_shift_socket_pair[0], &arg_uid_shift, sizeof(arg_uid_shift), MSG_NOSIGNAL);
- if (l < 0) {
- r = log_error_errno(errno, "Failed to send UID shift: %m");
- goto finish;
- }
- if (l != sizeof(arg_uid_shift)) {
- log_error("Short write while writing UID shift.");
- r = -EIO;
- goto finish;
- }
- }
- }
-
- /* Wait for the outer child. */
- r = wait_for_terminate_and_warn("namespace helper", pid, NULL);
- if (r < 0)
- goto finish;
- if (r != 0) {
- r = -EIO;
- goto finish;
- }
- pid = 0;
-
- /* And now retrieve the PID of the inner child. */
- l = recv(pid_socket_pair[0], &pid, sizeof(pid), 0);
- if (l < 0) {
- r = log_error_errno(errno, "Failed to read inner child PID: %m");
- goto finish;
- }
- if (l != sizeof(pid)) {
- log_error("Short read while reading inner child PID.");
- r = EIO;
- goto finish;
- }
-
- /* We also retrieve container UUID in case it was generated by outer child */
- l = recv(uuid_socket_pair[0], &arg_uuid, sizeof(arg_uuid), 0);
- if (l < 0) {
- r = log_error_errno(errno, "Failed to read container machine ID: %m");
- goto finish;
- }
- if (l != sizeof(arg_uuid)) {
- log_error("Short read while reading container machined ID.");
- r = EIO;
- goto finish;
- }
-
- /* We also retrieve the socket used for notifications generated by outer child */
- notify_socket = receive_one_fd(notify_socket_pair[0], 0);
- if (notify_socket < 0) {
- r = log_error_errno(errno, "Failed to receive notification socket from the outer child: %m");
- goto finish;
- }
-
- log_debug("Init process invoked as PID " PID_FMT, pid);
-
- if (arg_userns_mode != USER_NAMESPACE_NO) {
- if (!barrier_place_and_sync(&barrier)) { /* #1 */
- log_error("Child died too early.");
- r = -ESRCH;
- goto finish;
- }
-
- r = setup_uid_map(pid);
- if (r < 0)
- goto finish;
-
- (void) barrier_place(&barrier); /* #2 */
- }
-
- if (arg_private_network) {
-
- r = move_network_interfaces(pid, arg_network_interfaces);
- if (r < 0)
- goto finish;
-
- if (arg_network_veth) {
- r = setup_veth(arg_machine, pid, veth_name,
- arg_network_bridge || arg_network_zone);
- if (r < 0)
- goto finish;
- else if (r > 0)
- ifi = r;
-
- if (arg_network_bridge) {
- /* Add the interface to a bridge */
- r = setup_bridge(veth_name, arg_network_bridge, false);
- if (r < 0)
- goto finish;
- if (r > 0)
- ifi = r;
- } else if (arg_network_zone) {
- /* Add the interface to a bridge, possibly creating it */
- r = setup_bridge(veth_name, arg_network_zone, true);
- if (r < 0)
- goto finish;
- if (r > 0)
- ifi = r;
- }
- }
-
- r = setup_veth_extra(arg_machine, pid, arg_network_veth_extra);
- if (r < 0)
- goto finish;
-
- /* We created the primary and extra veth links now; let's remember this, so that we know to
- remove them later on. Note that we don't bother with removing veth links that were created
- here when their setup failed half-way, because in that case the kernel should be able to
- remove them on its own, since they cannot be referenced by anything yet. */
- veth_created = true;
-
- r = setup_macvlan(arg_machine, pid, arg_network_macvlan);
- if (r < 0)
- goto finish;
-
- r = setup_ipvlan(arg_machine, pid, arg_network_ipvlan);
- if (r < 0)
- goto finish;
- }
-
- if (arg_register) {
- r = register_machine(
- arg_machine,
- pid,
- arg_directory,
- arg_uuid,
- ifi,
- arg_slice,
- arg_custom_mounts, arg_n_custom_mounts,
- arg_kill_signal,
- arg_property,
- arg_keep_unit,
- arg_container_service_name);
- if (r < 0)
- goto finish;
- }
-
- r = sync_cgroup(pid, arg_unified_cgroup_hierarchy);
- if (r < 0)
- goto finish;
-
- if (arg_keep_unit) {
- r = create_subcgroup(pid, arg_unified_cgroup_hierarchy);
- if (r < 0)
- goto finish;
- }
-
- r = chown_cgroup(pid, arg_uid_shift);
- if (r < 0)
- goto finish;
-
- /* Notify the child that the parent is ready with all
- * its setup (including cgroup-ification), and that
- * the child can now hand over control to the code to
- * run inside the container. */
- (void) barrier_place(&barrier); /* #3 */
-
- /* Block SIGCHLD here, before notifying child.
- * process_pty() will handle it with the other signals. */
- assert_se(sigprocmask(SIG_BLOCK, &mask_chld, NULL) >= 0);
-
- /* Reset signal to default */
- r = default_signals(SIGCHLD, -1);
- if (r < 0) {
- log_error_errno(r, "Failed to reset SIGCHLD: %m");
- goto finish;
- }
-
- r = sd_event_new(&event);
- if (r < 0) {
- log_error_errno(r, "Failed to get default event source: %m");
- goto finish;
- }
-
- r = setup_sd_notify_parent(event, notify_socket, PID_TO_PTR(pid));
- if (r < 0)
- goto finish;
-
- /* Let the child know that we are ready and wait that the child is completely ready now. */
- if (!barrier_place_and_sync(&barrier)) { /* #4 */
- log_error("Child died too early.");
- r = -ESRCH;
- goto finish;
- }
-
- /* At this point we have made use of the UID we picked, and thus nss-mymachines will make them appear
- * in getpwuid(), thus we can release the /etc/passwd lock. */
- etc_passwd_lock = safe_close(etc_passwd_lock);
-
- sd_notifyf(false,
- "STATUS=Container running.\n"
- "X_NSPAWN_LEADER_PID=" PID_FMT, pid);
- if (!arg_notify_ready)
- sd_notify(false, "READY=1\n");
-
- if (arg_kill_signal > 0) {
- /* Try to kill the init system on SIGINT or SIGTERM */
- sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(pid));
- sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(pid));
- } else {
- /* Immediately exit */
- sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
- sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
- }
-
- /* simply exit on sigchld */
- sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
-
- if (arg_expose_ports) {
- r = expose_port_watch_rtnl(event, rtnl_socket_pair[0], on_address_change, &exposed, &rtnl);
- if (r < 0)
- goto finish;
-
- (void) expose_port_execute(rtnl, arg_expose_ports, &exposed);
- }
-
- rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
-
- r = pty_forward_new(event, master, PTY_FORWARD_IGNORE_VHANGUP | (interactive ? 0 : PTY_FORWARD_READ_ONLY), &forward);
- if (r < 0) {
- log_error_errno(r, "Failed to create PTY forwarder: %m");
- goto finish;
- }
-
- r = sd_event_loop(event);
- if (r < 0) {
- log_error_errno(r, "Failed to run event loop: %m");
- goto finish;
- }
-
- pty_forward_get_last_char(forward, &last_char);
-
- forward = pty_forward_free(forward);
-
- if (!arg_quiet && last_char != '\n')
- putc('\n', stdout);
-
- /* Kill if it is not dead yet anyway */
- if (arg_register && !arg_keep_unit)
- terminate_machine(pid);
-
- /* Normally redundant, but better safe than sorry */
- kill(pid, SIGKILL);
-
- r = wait_for_container(pid, &container_status);
- pid = 0;
-
- if (r < 0)
- /* We failed to wait for the container, or the
- * container exited abnormally */
- goto finish;
- else if (r > 0 || container_status == CONTAINER_TERMINATED) {
- /* The container exited with a non-zero
- * status, or with zero status and no reboot
- * was requested. */
- ret = r;
+ r = run(master,
+ console,
+ root_device, root_device_rw,
+ home_device, home_device_rw,
+ srv_device, srv_device_rw,
+ esp_device,
+ interactive, secondary,
+ fds,
+ veth_name, &veth_created,
+ &exposed,
+ &pid, &ret);
+ if (r <= 0)
break;
- }
-
- /* CONTAINER_REBOOTED, loop again */
-
- if (arg_keep_unit) {
- /* Special handling if we are running as a
- * service: instead of simply restarting the
- * machine we want to restart the entire
- * service, so let's inform systemd about this
- * with the special exit code 133. The service
- * file uses RestartForceExitStatus=133 so
- * that this results in a full nspawn
- * restart. This is necessary since we might
- * have cgroup parameters set we want to have
- * flushed out. */
- ret = 133;
- r = 0;
- break;
- }
-
- expose_port_flush(arg_expose_ports, &exposed);
-
- (void) remove_veth_links(veth_name, arg_network_veth_extra);
- veth_created = false;
}
finish: