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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
commit55944e5e40b1be2afc4855d8d2baf4b73d1876b5 (patch)
tree33f869f55a1b149e9b7c2b7e201867ca5dd52992 /src/nspawn/nspawn.c
parentInitial commit. (diff)
downloadsystemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.tar.xz
systemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.zip
Adding upstream version 255.4.upstream/255.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/nspawn/nspawn.c')
-rw-r--r--src/nspawn/nspawn.c5870
1 files changed, 5870 insertions, 0 deletions
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
new file mode 100644
index 0000000..e46cc1c
--- /dev/null
+++ b/src/nspawn/nspawn.c
@@ -0,0 +1,5870 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#if HAVE_BLKID
+#endif
+#include <errno.h>
+#include <getopt.h>
+#include <linux/fs.h>
+#include <linux/loop.h>
+#if HAVE_SELINUX
+#include <selinux/selinux.h>
+#endif
+#include <stdlib.h>
+#include <sys/file.h>
+#include <sys/ioctl.h>
+#include <sys/personality.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <termios.h>
+#include <unistd.h>
+
+#include "sd-bus.h"
+#include "sd-daemon.h"
+#include "sd-id128.h"
+
+#include "alloc-util.h"
+#include "ether-addr-util.h"
+#include "barrier.h"
+#include "base-filesystem.h"
+#include "blkid-util.h"
+#include "btrfs-util.h"
+#include "build.h"
+#include "bus-error.h"
+#include "bus-locator.h"
+#include "bus-util.h"
+#include "cap-list.h"
+#include "capability-util.h"
+#include "cgroup-util.h"
+#include "chase.h"
+#include "common-signal.h"
+#include "copy.h"
+#include "cpu-set-util.h"
+#include "creds-util.h"
+#include "dev-setup.h"
+#include "discover-image.h"
+#include "dissect-image.h"
+#include "env-util.h"
+#include "escape.h"
+#include "fd-util.h"
+#include "fdset.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "fs-util.h"
+#include "gpt.h"
+#include "hexdecoct.h"
+#include "hostname-setup.h"
+#include "hostname-util.h"
+#include "id128-util.h"
+#include "io-util.h"
+#include "log.h"
+#include "loop-util.h"
+#include "loopback-setup.h"
+#include "machine-credential.h"
+#include "macro.h"
+#include "main-func.h"
+#include "missing_sched.h"
+#include "mkdir.h"
+#include "mount-util.h"
+#include "mountpoint-util.h"
+#include "namespace-util.h"
+#include "netlink-util.h"
+#include "nspawn-bind-user.h"
+#include "nspawn-cgroup.h"
+#include "nspawn-def.h"
+#include "nspawn-expose-ports.h"
+#include "nspawn-mount.h"
+#include "nspawn-network.h"
+#include "nspawn-oci.h"
+#include "nspawn-patch-uid.h"
+#include "nspawn-register.h"
+#include "nspawn-seccomp.h"
+#include "nspawn-settings.h"
+#include "nspawn-setuid.h"
+#include "nspawn-stub-pid1.h"
+#include "nspawn-util.h"
+#include "nspawn.h"
+#include "nulstr-util.h"
+#include "os-util.h"
+#include "pager.h"
+#include "parse-argument.h"
+#include "parse-util.h"
+#include "pretty-print.h"
+#include "process-util.h"
+#include "ptyfwd.h"
+#include "random-util.h"
+#include "raw-clone.h"
+#include "resolve-util.h"
+#include "rlimit-util.h"
+#include "rm-rf.h"
+#include "seccomp-util.h"
+#include "selinux-util.h"
+#include "signal-util.h"
+#include "socket-util.h"
+#include "stat-util.h"
+#include "stdio-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "strv.h"
+#include "sysctl-util.h"
+#include "terminal-util.h"
+#include "tmpfile-util.h"
+#include "umask-util.h"
+#include "unit-name.h"
+#include "user-util.h"
+
+/* The notify socket inside the container it can use to talk to nspawn using the sd_notify(3) protocol */
+#define NSPAWN_NOTIFY_SOCKET_PATH "/run/host/notify"
+#define NSPAWN_MOUNT_TUNNEL "/run/host/incoming"
+
+#define EXIT_FORCE_RESTART 133
+
+typedef enum ContainerStatus {
+ CONTAINER_TERMINATED,
+ CONTAINER_REBOOTED,
+} ContainerStatus;
+
+static char *arg_directory = NULL;
+static char *arg_template = NULL;
+static char *arg_chdir = NULL;
+static char *arg_pivot_root_new = NULL;
+static char *arg_pivot_root_old = NULL;
+static char *arg_user = NULL;
+static uid_t arg_uid = UID_INVALID;
+static gid_t arg_gid = GID_INVALID;
+static gid_t* arg_supplementary_gids = NULL;
+static size_t arg_n_supplementary_gids = 0;
+static sd_id128_t arg_uuid = {};
+static char *arg_machine = NULL; /* The name used by the host to refer to this */
+static char *arg_hostname = NULL; /* The name the payload sees by default */
+static const char *arg_selinux_context = NULL;
+static const char *arg_selinux_apifs_context = NULL;
+static char *arg_slice = NULL;
+static bool arg_private_network = false;
+static bool arg_read_only = false;
+static StartMode arg_start_mode = START_PID1;
+static bool arg_ephemeral = false;
+static LinkJournal arg_link_journal = LINK_AUTO;
+static bool arg_link_journal_try = false;
+static uint64_t arg_caps_retain =
+ (1ULL << CAP_AUDIT_CONTROL) |
+ (1ULL << CAP_AUDIT_WRITE) |
+ (1ULL << CAP_CHOWN) |
+ (1ULL << CAP_DAC_OVERRIDE) |
+ (1ULL << CAP_DAC_READ_SEARCH) |
+ (1ULL << CAP_FOWNER) |
+ (1ULL << CAP_FSETID) |
+ (1ULL << CAP_IPC_OWNER) |
+ (1ULL << CAP_KILL) |
+ (1ULL << CAP_LEASE) |
+ (1ULL << CAP_LINUX_IMMUTABLE) |
+ (1ULL << CAP_MKNOD) |
+ (1ULL << CAP_NET_BIND_SERVICE) |
+ (1ULL << CAP_NET_BROADCAST) |
+ (1ULL << CAP_NET_RAW) |
+ (1ULL << CAP_SETFCAP) |
+ (1ULL << CAP_SETGID) |
+ (1ULL << CAP_SETPCAP) |
+ (1ULL << CAP_SETUID) |
+ (1ULL << CAP_SYS_ADMIN) |
+ (1ULL << CAP_SYS_BOOT) |
+ (1ULL << CAP_SYS_CHROOT) |
+ (1ULL << CAP_SYS_NICE) |
+ (1ULL << CAP_SYS_PTRACE) |
+ (1ULL << CAP_SYS_RESOURCE) |
+ (1ULL << CAP_SYS_TTY_CONFIG);
+static uint64_t arg_caps_ambient = 0;
+static CapabilityQuintet arg_full_capabilities = CAPABILITY_QUINTET_NULL;
+static CustomMount *arg_custom_mounts = NULL;
+static size_t arg_n_custom_mounts = 0;
+static char **arg_setenv = NULL;
+static bool arg_quiet = false;
+static bool arg_register = true;
+static bool arg_keep_unit = false;
+static char **arg_network_interfaces = NULL;
+static char **arg_network_macvlan = NULL;
+static char **arg_network_ipvlan = NULL;
+static bool arg_network_veth = false;
+static char **arg_network_veth_extra = NULL;
+static char *arg_network_bridge = NULL;
+static char *arg_network_zone = NULL;
+static char *arg_network_namespace_path = NULL;
+struct ether_addr arg_network_provided_mac = {};
+static PagerFlags arg_pager_flags = 0;
+static unsigned long arg_personality = PERSONALITY_INVALID;
+static char *arg_image = NULL;
+static char *arg_oci_bundle = NULL;
+static VolatileMode arg_volatile_mode = VOLATILE_NO;
+static ExposePort *arg_expose_ports = NULL;
+static char **arg_property = NULL;
+static sd_bus_message *arg_property_message = NULL;
+static UserNamespaceMode arg_userns_mode = USER_NAMESPACE_NO;
+static uid_t arg_uid_shift = UID_INVALID, arg_uid_range = 0x10000U;
+static UserNamespaceOwnership arg_userns_ownership = _USER_NAMESPACE_OWNERSHIP_INVALID;
+static int arg_kill_signal = 0;
+static CGroupUnified arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_UNKNOWN;
+static SettingsMask arg_settings_mask = 0;
+static int arg_settings_trusted = -1;
+static char **arg_parameters = NULL;
+static const char *arg_container_service_name = "systemd-nspawn";
+static bool arg_notify_ready = false;
+static bool arg_use_cgns = true;
+static unsigned long arg_clone_ns_flags = CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS;
+static MountSettingsMask arg_mount_settings = MOUNT_APPLY_APIVFS_RO|MOUNT_APPLY_TMPFS_TMP;
+static VeritySettings arg_verity_settings = VERITY_SETTINGS_DEFAULT;
+static char **arg_syscall_allow_list = NULL;
+static char **arg_syscall_deny_list = NULL;
+#if HAVE_SECCOMP
+static scmp_filter_ctx arg_seccomp = NULL;
+#endif
+static struct rlimit *arg_rlimit[_RLIMIT_MAX] = {};
+static bool arg_no_new_privileges = false;
+static int arg_oom_score_adjust = 0;
+static bool arg_oom_score_adjust_set = false;
+static CPUSet arg_cpu_set = {};
+static ResolvConfMode arg_resolv_conf = RESOLV_CONF_AUTO;
+static TimezoneMode arg_timezone = TIMEZONE_AUTO;
+static unsigned arg_console_width = UINT_MAX, arg_console_height = UINT_MAX;
+static DeviceNode* arg_extra_nodes = NULL;
+static size_t arg_n_extra_nodes = 0;
+static char **arg_sysctl = NULL;
+static ConsoleMode arg_console_mode = _CONSOLE_MODE_INVALID;
+static MachineCredential *arg_credentials = NULL;
+static size_t arg_n_credentials = 0;
+static char **arg_bind_user = NULL;
+static bool arg_suppress_sync = false;
+static char *arg_settings_filename = NULL;
+static Architecture arg_architecture = _ARCHITECTURE_INVALID;
+static ImagePolicy *arg_image_policy = NULL;
+
+STATIC_DESTRUCTOR_REGISTER(arg_directory, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_template, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_chdir, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_pivot_root_new, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_pivot_root_old, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_user, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_supplementary_gids, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_machine, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_hostname, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_slice, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_setenv, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_interfaces, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_macvlan, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_ipvlan, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_veth_extra, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_bridge, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_zone, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_network_namespace_path, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_oci_bundle, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_property, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_property_message, sd_bus_message_unrefp);
+STATIC_DESTRUCTOR_REGISTER(arg_parameters, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_verity_settings, verity_settings_done);
+STATIC_DESTRUCTOR_REGISTER(arg_syscall_allow_list, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_syscall_deny_list, strv_freep);
+#if HAVE_SECCOMP
+STATIC_DESTRUCTOR_REGISTER(arg_seccomp, seccomp_releasep);
+#endif
+STATIC_DESTRUCTOR_REGISTER(arg_cpu_set, cpu_set_reset);
+STATIC_DESTRUCTOR_REGISTER(arg_sysctl, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_bind_user, strv_freep);
+STATIC_DESTRUCTOR_REGISTER(arg_settings_filename, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_image_policy, image_policy_freep);
+
+static int handle_arg_console(const char *arg) {
+ if (streq(arg, "help")) {
+ puts("autopipe\n"
+ "interactive\n"
+ "passive\n"
+ "pipe\n"
+ "read-only");
+ return 0;
+ }
+
+ if (streq(arg, "interactive"))
+ arg_console_mode = CONSOLE_INTERACTIVE;
+ else if (streq(arg, "read-only"))
+ arg_console_mode = CONSOLE_READ_ONLY;
+ else if (streq(arg, "passive"))
+ arg_console_mode = CONSOLE_PASSIVE;
+ else if (streq(arg, "pipe")) {
+ if (isatty(STDIN_FILENO) > 0 && isatty(STDOUT_FILENO) > 0)
+ log_full(arg_quiet ? LOG_DEBUG : LOG_NOTICE,
+ "Console mode 'pipe' selected, but standard input/output are connected to an interactive TTY. "
+ "Most likely you want to use 'interactive' console mode for proper interactivity and shell job control. "
+ "Proceeding anyway.");
+
+ arg_console_mode = CONSOLE_PIPE;
+ } else if (streq(arg, "autopipe")) {
+ if (isatty(STDIN_FILENO) > 0 && isatty(STDOUT_FILENO) > 0)
+ arg_console_mode = CONSOLE_INTERACTIVE;
+ else
+ arg_console_mode = CONSOLE_PIPE;
+ } else
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unknown console mode: %s", optarg);
+
+ arg_settings_mask |= SETTING_CONSOLE_MODE;
+ return 1;
+}
+
+static int help(void) {
+ _cleanup_free_ char *link = NULL;
+ int r;
+
+ pager_open(arg_pager_flags);
+
+ r = terminal_urlify_man("systemd-nspawn", "1", &link);
+ if (r < 0)
+ return log_oom();
+
+ printf("%1$s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
+ "%5$sSpawn a command or OS in a light-weight container.%6$s\n\n"
+ " -h --help Show this help\n"
+ " --version Print version string\n"
+ " -q --quiet Do not show status information\n"
+ " --no-pager Do not pipe output into a pager\n"
+ " --settings=BOOLEAN Load additional settings from .nspawn file\n\n"
+ "%3$sImage:%4$s\n"
+ " -D --directory=PATH Root directory for the container\n"
+ " --template=PATH Initialize root directory from template directory,\n"
+ " if missing\n"
+ " -x --ephemeral Run container with snapshot of root directory, and\n"
+ " remove it after exit\n"
+ " -i --image=PATH Root file system disk image (or device node) for\n"
+ " the container\n"
+ " --image-policy=POLICY Specify disk image dissection policy\n"
+ " --oci-bundle=PATH OCI bundle directory\n"
+ " --read-only Mount the root directory read-only\n"
+ " --volatile[=MODE] Run the system in volatile mode\n"
+ " --root-hash=HASH Specify verity root hash for root disk image\n"
+ " --root-hash-sig=SIG Specify pkcs7 signature of root hash for verity\n"
+ " as a DER encoded PKCS7, either as a path to a file\n"
+ " or as an ASCII base64 encoded string prefixed by\n"
+ " 'base64:'\n"
+ " --verity-data=PATH Specify hash device for verity\n"
+ " --pivot-root=PATH[:PATH]\n"
+ " Pivot root to given directory in the container\n\n"
+ "%3$sExecution:%4$s\n"
+ " -a --as-pid2 Maintain a stub init as PID1, invoke binary as PID2\n"
+ " -b --boot Boot up full system (i.e. invoke init)\n"
+ " --chdir=PATH Set working directory in the container\n"
+ " -E --setenv=NAME[=VALUE] Pass an environment variable to PID 1\n"
+ " -u --user=USER Run the command under specified user or UID\n"
+ " --kill-signal=SIGNAL Select signal to use for shutting down PID 1\n"
+ " --notify-ready=BOOLEAN Receive notifications from the child init process\n"
+ " --suppress-sync=BOOLEAN\n"
+ " Suppress any form of disk data synchronization\n\n"
+ "%3$sSystem Identity:%4$s\n"
+ " -M --machine=NAME Set the machine name for the container\n"
+ " --hostname=NAME Override the hostname for the container\n"
+ " --uuid=UUID Set a specific machine UUID for the container\n\n"
+ "%3$sProperties:%4$s\n"
+ " -S --slice=SLICE Place the container in the specified slice\n"
+ " --property=NAME=VALUE Set scope unit property\n"
+ " --register=BOOLEAN Register container as machine\n"
+ " --keep-unit Do not register a scope for the machine, reuse\n"
+ " the service unit nspawn is running in\n\n"
+ "%3$sUser Namespacing:%4$s\n"
+ " --private-users=no Run without user namespacing\n"
+ " --private-users=yes|pick|identity\n"
+ " Run within user namespace, autoselect UID/GID range\n"
+ " --private-users=UIDBASE[:NUIDS]\n"
+ " Similar, but with user configured UID/GID range\n"
+ " --private-users-ownership=MODE\n"
+ " Adjust ('chown') or map ('map') OS tree ownership\n"
+ " to private UID/GID range\n"
+ " -U Equivalent to --private-users=pick and\n"
+ " --private-users-ownership=auto\n\n"
+ "%3$sNetworking:%4$s\n"
+ " --private-network Disable network in container\n"
+ " --network-interface=HOSTIF[:CONTAINERIF]\n"
+ " Assign an existing network interface to the\n"
+ " container\n"
+ " --network-macvlan=HOSTIF[:CONTAINERIF]\n"
+ " Create a macvlan network interface based on an\n"
+ " existing network interface to the container\n"
+ " --network-ipvlan=HOSTIF[:CONTAINERIF]\n"
+ " Create an ipvlan network interface based on an\n"
+ " existing network interface to the container\n"
+ " -n --network-veth Add a virtual Ethernet connection between host\n"
+ " and container\n"
+ " --network-veth-extra=HOSTIF[:CONTAINERIF]\n"
+ " Add an additional virtual Ethernet link between\n"
+ " host and container\n"
+ " --network-bridge=INTERFACE\n"
+ " Add a virtual Ethernet connection to the container\n"
+ " and attach it to an existing bridge on the host\n"
+ " --network-zone=NAME Similar, but attach the new interface to an\n"
+ " an automatically managed bridge interface\n"
+ " --network-namespace-path=PATH\n"
+ " Set network namespace to the one represented by\n"
+ " the specified kernel namespace file node\n"
+ " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n"
+ " Expose a container IP port on the host\n\n"
+ "%3$sSecurity:%4$s\n"
+ " --capability=CAP In addition to the default, retain specified\n"
+ " capability\n"
+ " --drop-capability=CAP Drop the specified capability from the default set\n"
+ " --ambient-capability=CAP\n"
+ " Sets the specified capability for the started\n"
+ " process. Not useful if booting a machine.\n"
+ " --no-new-privileges Set PR_SET_NO_NEW_PRIVS flag for container payload\n"
+ " --system-call-filter=LIST|~LIST\n"
+ " Permit/prohibit specific system calls\n"
+ " -Z --selinux-context=SECLABEL\n"
+ " Set the SELinux security context to be used by\n"
+ " processes in the container\n"
+ " -L --selinux-apifs-context=SECLABEL\n"
+ " Set the SELinux security context to be used by\n"
+ " API/tmpfs file systems in the container\n\n"
+ "%3$sResources:%4$s\n"
+ " --rlimit=NAME=LIMIT Set a resource limit for the payload\n"
+ " --oom-score-adjust=VALUE\n"
+ " Adjust the OOM score value for the payload\n"
+ " --cpu-affinity=CPUS Adjust the CPU affinity of the container\n"
+ " --personality=ARCH Pick personality for this container\n\n"
+ "%3$sIntegration:%4$s\n"
+ " --resolv-conf=MODE Select mode of /etc/resolv.conf initialization\n"
+ " --timezone=MODE Select mode of /etc/localtime initialization\n"
+ " --link-journal=MODE Link up guest journal, one of no, auto, guest, \n"
+ " host, try-guest, try-host\n"
+ " -j Equivalent to --link-journal=try-guest\n\n"
+ "%3$sMounts:%4$s\n"
+ " --bind=PATH[:PATH[:OPTIONS]]\n"
+ " Bind mount a file or directory from the host into\n"
+ " the container\n"
+ " --bind-ro=PATH[:PATH[:OPTIONS]\n"
+ " Similar, but creates a read-only bind mount\n"
+ " --inaccessible=PATH Over-mount file node with inaccessible node to mask\n"
+ " it\n"
+ " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n"
+ " --overlay=PATH[:PATH...]:PATH\n"
+ " Create an overlay mount from the host to \n"
+ " the container\n"
+ " --overlay-ro=PATH[:PATH...]:PATH\n"
+ " Similar, but creates a read-only overlay mount\n"
+ " --bind-user=NAME Bind user from host to container\n\n"
+ "%3$sInput/Output:%4$s\n"
+ " --console=MODE Select how stdin/stdout/stderr and /dev/console are\n"
+ " set up for the container.\n"
+ " -P --pipe Equivalent to --console=pipe\n\n"
+ "%3$sCredentials:%4$s\n"
+ " --set-credential=ID:VALUE\n"
+ " Pass a credential with literal value to container.\n"
+ " --load-credential=ID:PATH\n"
+ " Load credential to pass to container from file or\n"
+ " AF_UNIX stream socket.\n"
+ "\nSee the %2$s for details.\n",
+ program_invocation_short_name,
+ link,
+ ansi_underline(),
+ ansi_normal(),
+ ansi_highlight(),
+ ansi_normal());
+
+ return 0;
+}
+
+static int custom_mount_check_all(void) {
+ size_t i;
+
+ for (i = 0; i < arg_n_custom_mounts; i++) {
+ CustomMount *m = &arg_custom_mounts[i];
+
+ if (path_equal(m->destination, "/") && arg_userns_mode != USER_NAMESPACE_NO) {
+ if (arg_userns_ownership != USER_NAMESPACE_OWNERSHIP_OFF)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--private-users-ownership=own may not be combined with custom root mounts.");
+ if (arg_uid_shift == UID_INVALID)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--private-users with automatic UID shift may not be combined with custom root mounts.");
+ }
+ }
+
+ return 0;
+}
+
+static int detect_unified_cgroup_hierarchy_from_environment(void) {
+ const char *e, *var = "SYSTEMD_NSPAWN_UNIFIED_HIERARCHY";
+ int r;
+
+ /* Allow the user to control whether the unified hierarchy is used */
+
+ e = getenv(var);
+ if (!e) {
+ /* $UNIFIED_CGROUP_HIERARCHY has been renamed to $SYSTEMD_NSPAWN_UNIFIED_HIERARCHY. */
+ var = "UNIFIED_CGROUP_HIERARCHY";
+ e = getenv(var);
+ }
+
+ if (!isempty(e)) {
+ r = parse_boolean(e);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse $%s: %m", var);
+ if (r > 0)
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
+ else
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
+ }
+
+ return 0;
+}
+
+static int detect_unified_cgroup_hierarchy_from_image(const char *directory) {
+ int r;
+
+ /* Let's inherit the mode to use from the host system, but let's take into consideration what systemd
+ * in the image actually supports. */
+ r = cg_all_unified();
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine whether we are in all unified mode.");
+ if (r > 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 (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) > 0) {
+ /* Mixed cgroup hierarchy support was added in 233 */
+ r = systemd_installation_has_version(directory, "233");
+ 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;
+
+ log_debug("Using %s hierarchy for container.",
+ arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_NONE ? "legacy" :
+ arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_SYSTEMD ? "hybrid" : "unified");
+
+ return 0;
+}
+
+static int parse_capability_spec(const char *spec, uint64_t *ret_mask) {
+ uint64_t mask = 0;
+ int r;
+
+ for (;;) {
+ _cleanup_free_ char *t = NULL;
+
+ r = extract_first_word(&spec, &t, ",", 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse capability %s.", t);
+ if (r == 0)
+ break;
+
+ if (streq(t, "help")) {
+ for (int i = 0; i < capability_list_length(); i++) {
+ const char *name;
+
+ name = capability_to_name(i);
+ if (name)
+ puts(name);
+ }
+
+ return 0; /* quit */
+ }
+
+ if (streq(t, "all"))
+ mask = UINT64_MAX;
+ else {
+ r = capability_from_name(t);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse capability %s.", t);
+
+ mask |= 1ULL << r;
+ }
+ }
+
+ *ret_mask = mask;
+ return 1; /* continue */
+}
+
+static int parse_share_ns_env(const char *name, unsigned long ns_flag) {
+ int r;
+
+ r = getenv_bool(name);
+ if (r == -ENXIO)
+ return 0;
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse $%s: %m", name);
+
+ arg_clone_ns_flags = (arg_clone_ns_flags & ~ns_flag) | (r > 0 ? 0 : ns_flag);
+ arg_settings_mask |= SETTING_CLONE_NS_FLAGS;
+ return 0;
+}
+
+static int parse_mount_settings_env(void) {
+ const char *e;
+ int r;
+
+ r = getenv_bool("SYSTEMD_NSPAWN_TMPFS_TMP");
+ if (r < 0 && r != -ENXIO)
+ return log_error_errno(r, "Failed to parse $SYSTEMD_NSPAWN_TMPFS_TMP: %m");
+ if (r >= 0)
+ SET_FLAG(arg_mount_settings, MOUNT_APPLY_TMPFS_TMP, r > 0);
+
+ e = getenv("SYSTEMD_NSPAWN_API_VFS_WRITABLE");
+ if (streq_ptr(e, "network"))
+ arg_mount_settings |= MOUNT_APPLY_APIVFS_RO|MOUNT_APPLY_APIVFS_NETNS;
+
+ else if (e) {
+ r = parse_boolean(e);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse $SYSTEMD_NSPAWN_API_VFS_WRITABLE: %m");
+
+ SET_FLAG(arg_mount_settings, MOUNT_APPLY_APIVFS_RO, r == 0);
+ SET_FLAG(arg_mount_settings, MOUNT_APPLY_APIVFS_NETNS, false);
+ }
+
+ return 0;
+}
+
+static int parse_environment(void) {
+ const char *e;
+ int r;
+
+ r = parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_IPC", CLONE_NEWIPC);
+ if (r < 0)
+ return r;
+ r = parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_PID", CLONE_NEWPID);
+ if (r < 0)
+ return r;
+ r = parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_NS_UTS", CLONE_NEWUTS);
+ if (r < 0)
+ return r;
+ r = parse_share_ns_env("SYSTEMD_NSPAWN_SHARE_SYSTEM", CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS);
+ if (r < 0)
+ return r;
+
+ r = parse_mount_settings_env();
+ if (r < 0)
+ return r;
+
+ /* SYSTEMD_NSPAWN_USE_CGNS=0 can be used to disable CLONE_NEWCGROUP use,
+ * even if it is supported. If not supported, it has no effect. */
+ if (!cg_ns_supported())
+ arg_use_cgns = false;
+ else {
+ r = getenv_bool("SYSTEMD_NSPAWN_USE_CGNS");
+ if (r < 0) {
+ if (r != -ENXIO)
+ return log_error_errno(r, "Failed to parse $SYSTEMD_NSPAWN_USE_CGNS: %m");
+
+ arg_use_cgns = true;
+ } else {
+ arg_use_cgns = r > 0;
+ arg_settings_mask |= SETTING_USE_CGNS;
+ }
+ }
+
+ e = getenv("SYSTEMD_NSPAWN_CONTAINER_SERVICE");
+ if (e)
+ arg_container_service_name = e;
+
+ e = getenv("SYSTEMD_NSPAWN_NETWORK_MAC");
+ if (e) {
+ r = parse_ether_addr(e, &arg_network_provided_mac);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse provided MAC address via environment variable");
+ }
+
+ r = getenv_bool("SYSTEMD_SUPPRESS_SYNC");
+ if (r >= 0)
+ arg_suppress_sync = r;
+ else if (r != -ENXIO)
+ log_debug_errno(r, "Failed to parse $SYSTEMD_SUPPRESS_SYNC, ignoring: %m");
+
+ return detect_unified_cgroup_hierarchy_from_environment();
+}
+
+static int parse_argv(int argc, char *argv[]) {
+ enum {
+ ARG_VERSION = 0x100,
+ ARG_PRIVATE_NETWORK,
+ ARG_UUID,
+ ARG_READ_ONLY,
+ ARG_CAPABILITY,
+ ARG_AMBIENT_CAPABILITY,
+ ARG_DROP_CAPABILITY,
+ ARG_LINK_JOURNAL,
+ ARG_BIND,
+ ARG_BIND_RO,
+ ARG_TMPFS,
+ ARG_OVERLAY,
+ ARG_OVERLAY_RO,
+ ARG_INACCESSIBLE,
+ ARG_SHARE_SYSTEM,
+ ARG_REGISTER,
+ ARG_KEEP_UNIT,
+ ARG_NETWORK_INTERFACE,
+ ARG_NETWORK_MACVLAN,
+ ARG_NETWORK_IPVLAN,
+ ARG_NETWORK_BRIDGE,
+ ARG_NETWORK_ZONE,
+ ARG_NETWORK_VETH_EXTRA,
+ ARG_NETWORK_NAMESPACE_PATH,
+ ARG_PERSONALITY,
+ ARG_VOLATILE,
+ ARG_TEMPLATE,
+ ARG_PROPERTY,
+ ARG_PRIVATE_USERS,
+ ARG_KILL_SIGNAL,
+ ARG_SETTINGS,
+ ARG_CHDIR,
+ ARG_PIVOT_ROOT,
+ ARG_PRIVATE_USERS_CHOWN,
+ ARG_PRIVATE_USERS_OWNERSHIP,
+ ARG_NOTIFY_READY,
+ ARG_ROOT_HASH,
+ ARG_ROOT_HASH_SIG,
+ ARG_VERITY_DATA,
+ ARG_SYSTEM_CALL_FILTER,
+ ARG_RLIMIT,
+ ARG_HOSTNAME,
+ ARG_NO_NEW_PRIVILEGES,
+ ARG_OOM_SCORE_ADJUST,
+ ARG_CPU_AFFINITY,
+ ARG_RESOLV_CONF,
+ ARG_TIMEZONE,
+ ARG_CONSOLE,
+ ARG_PIPE,
+ ARG_OCI_BUNDLE,
+ ARG_NO_PAGER,
+ ARG_SET_CREDENTIAL,
+ ARG_LOAD_CREDENTIAL,
+ ARG_BIND_USER,
+ ARG_SUPPRESS_SYNC,
+ ARG_IMAGE_POLICY,
+ };
+
+ static const struct option options[] = {
+ { "help", no_argument, NULL, 'h' },
+ { "version", no_argument, NULL, ARG_VERSION },
+ { "directory", required_argument, NULL, 'D' },
+ { "template", required_argument, NULL, ARG_TEMPLATE },
+ { "ephemeral", no_argument, NULL, 'x' },
+ { "user", required_argument, NULL, 'u' },
+ { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK },
+ { "as-pid2", no_argument, NULL, 'a' },
+ { "boot", no_argument, NULL, 'b' },
+ { "uuid", required_argument, NULL, ARG_UUID },
+ { "read-only", no_argument, NULL, ARG_READ_ONLY },
+ { "capability", required_argument, NULL, ARG_CAPABILITY },
+ { "ambient-capability", required_argument, NULL, ARG_AMBIENT_CAPABILITY },
+ { "drop-capability", required_argument, NULL, ARG_DROP_CAPABILITY },
+ { "no-new-privileges", required_argument, NULL, ARG_NO_NEW_PRIVILEGES },
+ { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL },
+ { "bind", required_argument, NULL, ARG_BIND },
+ { "bind-ro", required_argument, NULL, ARG_BIND_RO },
+ { "tmpfs", required_argument, NULL, ARG_TMPFS },
+ { "overlay", required_argument, NULL, ARG_OVERLAY },
+ { "overlay-ro", required_argument, NULL, ARG_OVERLAY_RO },
+ { "inaccessible", required_argument, NULL, ARG_INACCESSIBLE },
+ { "machine", required_argument, NULL, 'M' },
+ { "hostname", required_argument, NULL, ARG_HOSTNAME },
+ { "slice", required_argument, NULL, 'S' },
+ { "setenv", required_argument, NULL, 'E' },
+ { "selinux-context", required_argument, NULL, 'Z' },
+ { "selinux-apifs-context", required_argument, NULL, 'L' },
+ { "quiet", no_argument, NULL, 'q' },
+ { "share-system", no_argument, NULL, ARG_SHARE_SYSTEM }, /* not documented */
+ { "register", required_argument, NULL, ARG_REGISTER },
+ { "keep-unit", no_argument, NULL, ARG_KEEP_UNIT },
+ { "network-interface", required_argument, NULL, ARG_NETWORK_INTERFACE },
+ { "network-macvlan", required_argument, NULL, ARG_NETWORK_MACVLAN },
+ { "network-ipvlan", required_argument, NULL, ARG_NETWORK_IPVLAN },
+ { "network-veth", no_argument, NULL, 'n' },
+ { "network-veth-extra", required_argument, NULL, ARG_NETWORK_VETH_EXTRA },
+ { "network-bridge", required_argument, NULL, ARG_NETWORK_BRIDGE },
+ { "network-zone", required_argument, NULL, ARG_NETWORK_ZONE },
+ { "network-namespace-path", required_argument, NULL, ARG_NETWORK_NAMESPACE_PATH },
+ { "personality", required_argument, NULL, ARG_PERSONALITY },
+ { "image", required_argument, NULL, 'i' },
+ { "volatile", optional_argument, NULL, ARG_VOLATILE },
+ { "port", required_argument, NULL, 'p' },
+ { "property", required_argument, NULL, ARG_PROPERTY },
+ { "private-users", optional_argument, NULL, ARG_PRIVATE_USERS },
+ { "private-users-chown", optional_argument, NULL, ARG_PRIVATE_USERS_CHOWN }, /* obsolete */
+ { "private-users-ownership",required_argument, NULL, ARG_PRIVATE_USERS_OWNERSHIP},
+ { "kill-signal", required_argument, NULL, ARG_KILL_SIGNAL },
+ { "settings", required_argument, NULL, ARG_SETTINGS },
+ { "chdir", required_argument, NULL, ARG_CHDIR },
+ { "pivot-root", required_argument, NULL, ARG_PIVOT_ROOT },
+ { "notify-ready", required_argument, NULL, ARG_NOTIFY_READY },
+ { "root-hash", required_argument, NULL, ARG_ROOT_HASH },
+ { "root-hash-sig", required_argument, NULL, ARG_ROOT_HASH_SIG },
+ { "verity-data", required_argument, NULL, ARG_VERITY_DATA },
+ { "system-call-filter", required_argument, NULL, ARG_SYSTEM_CALL_FILTER },
+ { "rlimit", required_argument, NULL, ARG_RLIMIT },
+ { "oom-score-adjust", required_argument, NULL, ARG_OOM_SCORE_ADJUST },
+ { "cpu-affinity", required_argument, NULL, ARG_CPU_AFFINITY },
+ { "resolv-conf", required_argument, NULL, ARG_RESOLV_CONF },
+ { "timezone", required_argument, NULL, ARG_TIMEZONE },
+ { "console", required_argument, NULL, ARG_CONSOLE },
+ { "pipe", no_argument, NULL, ARG_PIPE },
+ { "oci-bundle", required_argument, NULL, ARG_OCI_BUNDLE },
+ { "no-pager", no_argument, NULL, ARG_NO_PAGER },
+ { "set-credential", required_argument, NULL, ARG_SET_CREDENTIAL },
+ { "load-credential", required_argument, NULL, ARG_LOAD_CREDENTIAL },
+ { "bind-user", required_argument, NULL, ARG_BIND_USER },
+ { "suppress-sync", required_argument, NULL, ARG_SUPPRESS_SYNC },
+ { "image-policy", required_argument, NULL, ARG_IMAGE_POLICY },
+ {}
+ };
+
+ int c, r;
+ uint64_t plus = 0, minus = 0;
+ bool mask_all_settings = false, mask_no_settings = false;
+
+ assert(argc >= 0);
+ assert(argv);
+
+ /* Resetting to 0 forces the invocation of an internal initialization routine of getopt_long()
+ * that checks for GNU extensions in optstring ('-' or '+' at the beginning). */
+ optind = 0;
+ while ((c = getopt_long(argc, argv, "+hD:u:abL:M:jS:Z:qi:xp:nUE:P", options, NULL)) >= 0)
+ switch (c) {
+
+ case 'h':
+ return help();
+
+ case ARG_VERSION:
+ return version();
+
+ case 'D':
+ r = parse_path_argument(optarg, false, &arg_directory);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_DIRECTORY;
+ break;
+
+ case ARG_TEMPLATE:
+ r = parse_path_argument(optarg, false, &arg_template);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_DIRECTORY;
+ break;
+
+ case 'i':
+ r = parse_path_argument(optarg, false, &arg_image);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_DIRECTORY;
+ break;
+
+ case ARG_OCI_BUNDLE:
+ r = parse_path_argument(optarg, false, &arg_oci_bundle);
+ if (r < 0)
+ return r;
+
+ break;
+
+ case 'x':
+ arg_ephemeral = true;
+ arg_settings_mask |= SETTING_EPHEMERAL;
+ break;
+
+ case 'u':
+ r = free_and_strdup(&arg_user, optarg);
+ if (r < 0)
+ return log_oom();
+
+ arg_settings_mask |= SETTING_USER;
+ break;
+
+ case ARG_NETWORK_ZONE: {
+ _cleanup_free_ char *j = NULL;
+
+ j = strjoin("vz-", optarg);
+ if (!j)
+ return log_oom();
+
+ if (!ifname_valid(j))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Network zone name not valid: %s", j);
+
+ free_and_replace(arg_network_zone, j);
+
+ arg_network_veth = true;
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+ }
+
+ case ARG_NETWORK_BRIDGE:
+
+ if (!ifname_valid(optarg))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Bridge interface name not valid: %s", optarg);
+
+ r = free_and_strdup(&arg_network_bridge, optarg);
+ if (r < 0)
+ return log_oom();
+
+ _fallthrough_;
+ case 'n':
+ arg_network_veth = true;
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case ARG_NETWORK_VETH_EXTRA:
+ r = veth_extra_parse(&arg_network_veth_extra, optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --network-veth-extra= parameter: %s", optarg);
+
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case ARG_NETWORK_INTERFACE:
+ r = interface_pair_parse(&arg_network_interfaces, optarg);
+ if (r < 0)
+ return r;
+
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case ARG_NETWORK_MACVLAN:
+ r = macvlan_pair_parse(&arg_network_macvlan, optarg);
+ if (r < 0)
+ return r;
+
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case ARG_NETWORK_IPVLAN:
+ r = ipvlan_pair_parse(&arg_network_ipvlan, optarg);
+ if (r < 0)
+ return r;
+
+ _fallthrough_;
+ case ARG_PRIVATE_NETWORK:
+ arg_private_network = true;
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case ARG_NETWORK_NAMESPACE_PATH:
+ r = parse_path_argument(optarg, false, &arg_network_namespace_path);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_NETWORK;
+ break;
+
+ case 'b':
+ if (arg_start_mode == START_PID2)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--boot and --as-pid2 may not be combined.");
+
+ arg_start_mode = START_BOOT;
+ arg_settings_mask |= SETTING_START_MODE;
+ break;
+
+ case 'a':
+ if (arg_start_mode == START_BOOT)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--boot and --as-pid2 may not be combined.");
+
+ arg_start_mode = START_PID2;
+ arg_settings_mask |= SETTING_START_MODE;
+ break;
+
+ case ARG_UUID:
+ r = id128_from_string_nonzero(optarg, &arg_uuid);
+ if (r == -ENXIO)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Machine UUID may not be all zeroes.");
+ if (r < 0)
+ return log_error_errno(r, "Invalid UUID: %s", optarg);
+
+ arg_settings_mask |= SETTING_MACHINE_ID;
+ break;
+
+ case 'S': {
+ _cleanup_free_ char *mangled = NULL;
+
+ r = unit_name_mangle_with_suffix(optarg, NULL, UNIT_NAME_MANGLE_WARN, ".slice", &mangled);
+ if (r < 0)
+ return log_oom();
+
+ free_and_replace(arg_slice, mangled);
+ arg_settings_mask |= SETTING_SLICE;
+ break;
+ }
+
+ case 'M':
+ if (isempty(optarg))
+ arg_machine = mfree(arg_machine);
+ else {
+ if (!hostname_is_valid(optarg, 0))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Invalid machine name: %s", optarg);
+
+ r = free_and_strdup(&arg_machine, optarg);
+ if (r < 0)
+ return log_oom();
+ }
+ break;
+
+ case ARG_HOSTNAME:
+ if (isempty(optarg))
+ arg_hostname = mfree(arg_hostname);
+ else {
+ if (!hostname_is_valid(optarg, 0))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Invalid hostname: %s", optarg);
+
+ r = free_and_strdup(&arg_hostname, optarg);
+ if (r < 0)
+ return log_oom();
+ }
+
+ arg_settings_mask |= SETTING_HOSTNAME;
+ break;
+
+ case 'Z':
+ arg_selinux_context = optarg;
+ break;
+
+ case 'L':
+ arg_selinux_apifs_context = optarg;
+ break;
+
+ case ARG_READ_ONLY:
+ arg_read_only = true;
+ arg_settings_mask |= SETTING_READ_ONLY;
+ break;
+
+ case ARG_AMBIENT_CAPABILITY: {
+ uint64_t m;
+ r = parse_capability_spec(optarg, &m);
+ if (r <= 0)
+ return r;
+ arg_caps_ambient |= m;
+ arg_settings_mask |= SETTING_CAPABILITY;
+ break;
+ }
+ case ARG_CAPABILITY:
+ case ARG_DROP_CAPABILITY: {
+ uint64_t m;
+ r = parse_capability_spec(optarg, &m);
+ if (r <= 0)
+ return r;
+
+ if (c == ARG_CAPABILITY)
+ plus |= m;
+ else
+ minus |= m;
+ arg_settings_mask |= SETTING_CAPABILITY;
+ break;
+ }
+ case ARG_NO_NEW_PRIVILEGES:
+ r = parse_boolean(optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --no-new-privileges= argument: %s", optarg);
+
+ arg_no_new_privileges = r;
+ arg_settings_mask |= SETTING_NO_NEW_PRIVILEGES;
+ break;
+
+ case 'j':
+ arg_link_journal = LINK_GUEST;
+ arg_link_journal_try = true;
+ arg_settings_mask |= SETTING_LINK_JOURNAL;
+ break;
+
+ case ARG_LINK_JOURNAL:
+ r = parse_link_journal(optarg, &arg_link_journal, &arg_link_journal_try);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse link journal mode %s", optarg);
+
+ arg_settings_mask |= SETTING_LINK_JOURNAL;
+ break;
+
+ case ARG_BIND:
+ case ARG_BIND_RO:
+ r = bind_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg, c == ARG_BIND_RO);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --bind(-ro)= argument %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
+ break;
+
+ case ARG_TMPFS:
+ r = tmpfs_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --tmpfs= argument %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
+ break;
+
+ case ARG_OVERLAY:
+ case ARG_OVERLAY_RO:
+ r = overlay_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg, c == ARG_OVERLAY_RO);
+ if (r == -EADDRNOTAVAIL)
+ return log_error_errno(r, "--overlay(-ro)= needs at least two colon-separated directories specified.");
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --overlay(-ro)= argument %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
+ break;
+
+ case ARG_INACCESSIBLE:
+ r = inaccessible_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --inaccessible= argument %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_CUSTOM_MOUNTS;
+ break;
+
+ case 'E':
+ r = strv_env_replace_strdup_passthrough(&arg_setenv, optarg);
+ if (r < 0)
+ return log_error_errno(r, "Cannot assign environment variable %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_ENVIRONMENT;
+ break;
+
+ case 'q':
+ arg_quiet = true;
+ break;
+
+ case ARG_SHARE_SYSTEM:
+ /* We don't officially support this anymore, except for compat reasons. People should use the
+ * $SYSTEMD_NSPAWN_SHARE_* environment variables instead. */
+ log_warning("Please do not use --share-system anymore, use $SYSTEMD_NSPAWN_SHARE_* instead.");
+ arg_clone_ns_flags = 0;
+ break;
+
+ case ARG_REGISTER:
+ r = parse_boolean(optarg);
+ if (r < 0) {
+ log_error("Failed to parse --register= argument: %s", optarg);
+ return r;
+ }
+
+ arg_register = r;
+ break;
+
+ case ARG_KEEP_UNIT:
+ arg_keep_unit = true;
+ break;
+
+ case ARG_PERSONALITY:
+
+ arg_personality = personality_from_string(optarg);
+ if (arg_personality == PERSONALITY_INVALID)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Unknown or unsupported personality '%s'.", optarg);
+
+ arg_settings_mask |= SETTING_PERSONALITY;
+ break;
+
+ case ARG_VOLATILE:
+
+ if (!optarg)
+ arg_volatile_mode = VOLATILE_YES;
+ else if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(volatile_mode, VolatileMode, _VOLATILE_MODE_MAX);
+ return 0;
+ } else {
+ VolatileMode m;
+
+ m = volatile_mode_from_string(optarg);
+ if (m < 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Failed to parse --volatile= argument: %s", optarg);
+ else
+ arg_volatile_mode = m;
+ }
+
+ arg_settings_mask |= SETTING_VOLATILE_MODE;
+ break;
+
+ case 'p':
+ r = expose_port_parse(&arg_expose_ports, optarg);
+ if (r == -EEXIST)
+ return log_error_errno(r, "Duplicate port specification: %s", optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse host port %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_EXPOSE_PORTS;
+ break;
+
+ case ARG_PROPERTY:
+ if (strv_extend(&arg_property, optarg) < 0)
+ return log_oom();
+
+ break;
+
+ case ARG_PRIVATE_USERS: {
+ int boolean;
+
+ if (!optarg)
+ boolean = true;
+ else if (!in_charset(optarg, DIGITS))
+ /* do *not* parse numbers as booleans */
+ boolean = parse_boolean(optarg);
+ else
+ boolean = -1;
+
+ if (boolean == 0) {
+ /* no: User namespacing off */
+ arg_userns_mode = USER_NAMESPACE_NO;
+ arg_uid_shift = UID_INVALID;
+ arg_uid_range = UINT32_C(0x10000);
+ } else if (boolean > 0) {
+ /* yes: User namespacing on, UID range is read from root dir */
+ arg_userns_mode = USER_NAMESPACE_FIXED;
+ arg_uid_shift = UID_INVALID;
+ arg_uid_range = UINT32_C(0x10000);
+ } else if (streq(optarg, "pick")) {
+ /* pick: User namespacing on, UID range is picked randomly */
+ arg_userns_mode = USER_NAMESPACE_PICK; /* Note that arg_userns_ownership is
+ * implied by USER_NAMESPACE_PICK
+ * further down. */
+ arg_uid_shift = UID_INVALID;
+ arg_uid_range = UINT32_C(0x10000);
+
+ } else if (streq(optarg, "identity")) {
+ /* identity: User namespaces on, UID range is map the 0…0xFFFF range to
+ * itself, i.e. we don't actually map anything, but do take benefit of
+ * isolation of capability sets. */
+ arg_userns_mode = USER_NAMESPACE_FIXED;
+ arg_uid_shift = 0;
+ arg_uid_range = UINT32_C(0x10000);
+ } else {
+ _cleanup_free_ char *buffer = NULL;
+ const char *range, *shift;
+
+ /* anything else: User namespacing on, UID range is explicitly configured */
+
+ range = strchr(optarg, ':');
+ if (range) {
+ buffer = strndup(optarg, range - optarg);
+ if (!buffer)
+ return log_oom();
+ shift = buffer;
+
+ range++;
+ r = safe_atou32(range, &arg_uid_range);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse UID range \"%s\": %m", range);
+ } else
+ shift = optarg;
+
+ r = parse_uid(shift, &arg_uid_shift);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse UID \"%s\": %m", optarg);
+
+ arg_userns_mode = USER_NAMESPACE_FIXED;
+
+ if (!userns_shift_range_valid(arg_uid_shift, arg_uid_range))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "UID range cannot be empty or go beyond " UID_FMT ".", UID_INVALID);
+ }
+
+ arg_settings_mask |= SETTING_USERNS;
+ break;
+ }
+
+ case 'U':
+ if (userns_supported()) {
+ arg_userns_mode = USER_NAMESPACE_PICK; /* Note that arg_userns_ownership is
+ * implied by USER_NAMESPACE_PICK
+ * further down. */
+ arg_uid_shift = UID_INVALID;
+ arg_uid_range = UINT32_C(0x10000);
+
+ arg_settings_mask |= SETTING_USERNS;
+ }
+
+ break;
+
+ case ARG_PRIVATE_USERS_CHOWN:
+ arg_userns_ownership = USER_NAMESPACE_OWNERSHIP_CHOWN;
+
+ arg_settings_mask |= SETTING_USERNS;
+ break;
+
+ case ARG_PRIVATE_USERS_OWNERSHIP:
+ if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(user_namespace_ownership, UserNamespaceOwnership, _USER_NAMESPACE_OWNERSHIP_MAX);
+ return 0;
+ }
+
+ arg_userns_ownership = user_namespace_ownership_from_string(optarg);
+ if (arg_userns_ownership < 0)
+ return log_error_errno(arg_userns_ownership, "Cannot parse --user-namespace-ownership= value: %s", optarg);
+
+ arg_settings_mask |= SETTING_USERNS;
+ break;
+
+ case ARG_KILL_SIGNAL:
+ if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(signal, int, _NSIG);
+ return 0;
+ }
+
+ arg_kill_signal = signal_from_string(optarg);
+ if (arg_kill_signal < 0)
+ return log_error_errno(arg_kill_signal, "Cannot parse signal: %s", optarg);
+
+ arg_settings_mask |= SETTING_KILL_SIGNAL;
+ break;
+
+ case ARG_SETTINGS:
+
+ /* no → do not read files
+ * yes → read files, do not override cmdline, trust only subset
+ * override → read files, override cmdline, trust only subset
+ * trusted → read files, do not override cmdline, trust all
+ */
+
+ r = parse_boolean(optarg);
+ if (r < 0) {
+ if (streq(optarg, "trusted")) {
+ mask_all_settings = false;
+ mask_no_settings = false;
+ arg_settings_trusted = true;
+
+ } else if (streq(optarg, "override")) {
+ mask_all_settings = false;
+ mask_no_settings = true;
+ arg_settings_trusted = -1;
+ } else
+ return log_error_errno(r, "Failed to parse --settings= argument: %s", optarg);
+ } else if (r > 0) {
+ /* yes */
+ mask_all_settings = false;
+ mask_no_settings = false;
+ arg_settings_trusted = -1;
+ } else {
+ /* no */
+ mask_all_settings = true;
+ mask_no_settings = false;
+ arg_settings_trusted = false;
+ }
+
+ break;
+
+ case ARG_CHDIR:
+ if (!path_is_absolute(optarg))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Working directory %s is not an absolute path.", optarg);
+
+ r = free_and_strdup(&arg_chdir, optarg);
+ if (r < 0)
+ return log_oom();
+
+ arg_settings_mask |= SETTING_WORKING_DIRECTORY;
+ break;
+
+ case ARG_PIVOT_ROOT:
+ r = pivot_root_parse(&arg_pivot_root_new, &arg_pivot_root_old, optarg);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --pivot-root= argument %s: %m", optarg);
+
+ arg_settings_mask |= SETTING_PIVOT_ROOT;
+ break;
+
+ case ARG_NOTIFY_READY:
+ r = parse_boolean(optarg);
+ if (r < 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "%s is not a valid notify mode. Valid modes are: yes, no, and ready.", optarg);
+ arg_notify_ready = r;
+ arg_settings_mask |= SETTING_NOTIFY_READY;
+ break;
+
+ case ARG_ROOT_HASH: {
+ _cleanup_free_ void *k = NULL;
+ size_t l;
+
+ r = unhexmem(optarg, strlen(optarg), &k, &l);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse root hash: %s", optarg);
+ if (l < sizeof(sd_id128_t))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Root hash must be at least 128-bit long: %s", optarg);
+
+ free_and_replace(arg_verity_settings.root_hash, k);
+ arg_verity_settings.root_hash_size = l;
+ break;
+ }
+
+ case ARG_ROOT_HASH_SIG: {
+ char *value;
+ size_t l;
+ void *p;
+
+ if ((value = startswith(optarg, "base64:"))) {
+ r = unbase64mem(value, strlen(value), &p, &l);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse root hash signature '%s': %m", optarg);
+
+ } else {
+ r = read_full_file(optarg, (char**) &p, &l);
+ if (r < 0)
+ return log_error_errno(r, "Failed parse root hash signature file '%s': %m", optarg);
+ }
+
+ free_and_replace(arg_verity_settings.root_hash_sig, p);
+ arg_verity_settings.root_hash_sig_size = l;
+ break;
+ }
+
+ case ARG_VERITY_DATA:
+ r = parse_path_argument(optarg, false, &arg_verity_settings.data_path);
+ if (r < 0)
+ return r;
+ break;
+
+ case ARG_SYSTEM_CALL_FILTER: {
+ bool negative;
+ const char *items;
+
+ negative = optarg[0] == '~';
+ items = negative ? optarg + 1 : optarg;
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+
+ r = extract_first_word(&items, &word, NULL, 0);
+ if (r == 0)
+ break;
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse system call filter: %m");
+
+ if (negative)
+ r = strv_extend(&arg_syscall_deny_list, word);
+ else
+ r = strv_extend(&arg_syscall_allow_list, word);
+ if (r < 0)
+ return log_oom();
+ }
+
+ arg_settings_mask |= SETTING_SYSCALL_FILTER;
+ break;
+ }
+
+ case ARG_RLIMIT: {
+ const char *eq;
+ _cleanup_free_ char *name = NULL;
+ int rl;
+
+ if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(rlimit, int, _RLIMIT_MAX);
+ return 0;
+ }
+
+ eq = strchr(optarg, '=');
+ if (!eq)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--rlimit= expects an '=' assignment.");
+
+ name = strndup(optarg, eq - optarg);
+ if (!name)
+ return log_oom();
+
+ rl = rlimit_from_string_harder(name);
+ if (rl < 0)
+ return log_error_errno(rl, "Unknown resource limit: %s", name);
+
+ if (!arg_rlimit[rl]) {
+ arg_rlimit[rl] = new0(struct rlimit, 1);
+ if (!arg_rlimit[rl])
+ return log_oom();
+ }
+
+ r = rlimit_parse(rl, eq + 1, arg_rlimit[rl]);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse resource limit: %s", eq + 1);
+
+ arg_settings_mask |= SETTING_RLIMIT_FIRST << rl;
+ break;
+ }
+
+ case ARG_OOM_SCORE_ADJUST:
+ r = parse_oom_score_adjust(optarg, &arg_oom_score_adjust);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse --oom-score-adjust= parameter: %s", optarg);
+
+ arg_oom_score_adjust_set = true;
+ arg_settings_mask |= SETTING_OOM_SCORE_ADJUST;
+ break;
+
+ case ARG_CPU_AFFINITY: {
+ CPUSet cpuset;
+
+ r = parse_cpu_set(optarg, &cpuset);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse CPU affinity mask %s: %m", optarg);
+
+ cpu_set_reset(&arg_cpu_set);
+ arg_cpu_set = cpuset;
+ arg_settings_mask |= SETTING_CPU_AFFINITY;
+ break;
+ }
+
+ case ARG_RESOLV_CONF:
+ if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(resolv_conf_mode, ResolvConfMode, _RESOLV_CONF_MODE_MAX);
+ return 0;
+ }
+
+ arg_resolv_conf = resolv_conf_mode_from_string(optarg);
+ if (arg_resolv_conf < 0)
+ return log_error_errno(arg_resolv_conf,
+ "Failed to parse /etc/resolv.conf mode: %s", optarg);
+
+ arg_settings_mask |= SETTING_RESOLV_CONF;
+ break;
+
+ case ARG_TIMEZONE:
+ if (streq(optarg, "help")) {
+ DUMP_STRING_TABLE(timezone_mode, TimezoneMode, _TIMEZONE_MODE_MAX);
+ return 0;
+ }
+
+ arg_timezone = timezone_mode_from_string(optarg);
+ if (arg_timezone < 0)
+ return log_error_errno(arg_timezone,
+ "Failed to parse /etc/localtime mode: %s", optarg);
+
+ arg_settings_mask |= SETTING_TIMEZONE;
+ break;
+
+ case ARG_CONSOLE:
+ r = handle_arg_console(optarg);
+ if (r <= 0)
+ return r;
+ break;
+
+ case 'P':
+ case ARG_PIPE:
+ r = handle_arg_console("pipe");
+ if (r <= 0)
+ return r;
+ break;
+
+ case ARG_NO_PAGER:
+ arg_pager_flags |= PAGER_DISABLE;
+ break;
+
+ case ARG_SET_CREDENTIAL:
+ r = machine_credential_set(&arg_credentials, &arg_n_credentials, optarg);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_CREDENTIALS;
+ break;
+
+ case ARG_LOAD_CREDENTIAL:
+ r = machine_credential_load(&arg_credentials, &arg_n_credentials, optarg);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_CREDENTIALS;
+ break;
+
+ case ARG_BIND_USER:
+ if (!valid_user_group_name(optarg, 0))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Invalid user name to bind: %s", optarg);
+
+ if (strv_extend(&arg_bind_user, optarg) < 0)
+ return log_oom();
+
+ arg_settings_mask |= SETTING_BIND_USER;
+ break;
+
+ case ARG_SUPPRESS_SYNC:
+ r = parse_boolean_argument("--suppress-sync=", optarg, &arg_suppress_sync);
+ if (r < 0)
+ return r;
+
+ arg_settings_mask |= SETTING_SUPPRESS_SYNC;
+ break;
+
+ case ARG_IMAGE_POLICY:
+ r = parse_image_policy_argument(optarg, &arg_image_policy);
+ if (r < 0)
+ return r;
+ break;
+
+ case '?':
+ return -EINVAL;
+
+ default:
+ assert_not_reached();
+ }
+
+ if (argc > optind) {
+ strv_free(arg_parameters);
+ arg_parameters = strv_copy(argv + optind);
+ if (!arg_parameters)
+ return log_oom();
+
+ arg_settings_mask |= SETTING_START_MODE;
+ }
+
+ if (arg_ephemeral && arg_template && !arg_directory)
+ /* User asked for ephemeral execution but specified --template= instead of --directory=. Semantically
+ * such an invocation makes some sense, see https://github.com/systemd/systemd/issues/3667. Let's
+ * accept this here, and silently make "--ephemeral --template=" equivalent to "--ephemeral
+ * --directory=". */
+ arg_directory = TAKE_PTR(arg_template);
+
+ arg_caps_retain |= plus;
+ arg_caps_retain |= arg_private_network ? UINT64_C(1) << CAP_NET_ADMIN : 0;
+ arg_caps_retain &= ~minus;
+
+ /* Make sure to parse environment before we reset the settings mask below */
+ r = parse_environment();
+ if (r < 0)
+ return r;
+
+ /* Load all settings from .nspawn files */
+ if (mask_no_settings)
+ arg_settings_mask = 0;
+
+ /* Don't load any settings from .nspawn files */
+ if (mask_all_settings)
+ arg_settings_mask = _SETTINGS_MASK_ALL;
+
+ return 1;
+}
+
+static int verify_arguments(void) {
+ int r;
+
+ if (arg_start_mode == START_PID2 && arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN) {
+ /* If we are running the stub init in the container, we don't need to look at what the init
+ * in the container supports, because we are not using it. Let's immediately pick the right
+ * setting based on the host system configuration.
+ *
+ * We only do this, if the user didn't use an environment variable to override the detection.
+ */
+
+ r = cg_all_unified();
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine whether we are in all unified mode.");
+ if (r > 0)
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_ALL;
+ else if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) > 0)
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_SYSTEMD;
+ else
+ arg_unified_cgroup_hierarchy = CGROUP_UNIFIED_NONE;
+ }
+
+ if (arg_userns_mode != USER_NAMESPACE_NO)
+ arg_mount_settings |= MOUNT_USE_USERNS;
+
+ if (arg_private_network)
+ arg_mount_settings |= MOUNT_APPLY_APIVFS_NETNS;
+
+ if (!(arg_clone_ns_flags & CLONE_NEWPID) ||
+ !(arg_clone_ns_flags & CLONE_NEWUTS)) {
+ arg_register = false;
+ if (arg_start_mode != START_PID1)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--boot cannot be used without namespacing.");
+ }
+
+ if (arg_userns_ownership < 0)
+ arg_userns_ownership =
+ arg_userns_mode == USER_NAMESPACE_PICK ? USER_NAMESPACE_OWNERSHIP_AUTO :
+ USER_NAMESPACE_OWNERSHIP_OFF;
+
+ if (arg_start_mode == START_BOOT && arg_kill_signal <= 0)
+ arg_kill_signal = SIGRTMIN+3;
+
+ if (arg_volatile_mode != VOLATILE_NO) /* Make sure all file systems contained in the image are mounted read-only if we are in volatile mode */
+ arg_read_only = true;
+
+ if (has_custom_root_mount(arg_custom_mounts, arg_n_custom_mounts))
+ arg_read_only = true;
+
+ if (arg_keep_unit && arg_register && cg_pid_get_owner_uid(0, NULL) >= 0)
+ /* Save the user from accidentally registering either user-$SESSION.scope or user@.service.
+ * The latter is not technically a user session, but we don't need to labour the point. */
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--keep-unit --register=yes may not be used when invoked from a user session.");
+
+ if (arg_directory && arg_image)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--directory= and --image= may not be combined.");
+
+ if (arg_template && arg_image)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--template= and --image= may not be combined.");
+
+ if (arg_template && !(arg_directory || arg_machine))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--template= needs --directory= or --machine=.");
+
+ if (arg_ephemeral && arg_template)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--ephemeral and --template= may not be combined.");
+
+ /* Permit --ephemeral with --link-journal=try-* to satisfy principle of the least astonishment
+ * (by common sense, "try" means "do not fail if not possible") */
+ if (arg_ephemeral && !IN_SET(arg_link_journal, LINK_NO, LINK_AUTO) && !arg_link_journal_try)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--ephemeral and --link-journal={host,guest} may not be combined.");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO && !userns_supported())
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "--private-users= is not supported, kernel compiled without user namespace support.");
+
+ if (arg_userns_ownership == USER_NAMESPACE_OWNERSHIP_CHOWN && arg_read_only)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--read-only and --private-users-ownership=chown may not be combined.");
+
+ /* We don't support --private-users-ownership=chown together with any of the volatile modes since we
+ * couldn't change the read-only part of the tree (i.e. /usr) anyway, or because it would trigger a
+ * massive copy-up (in case of overlay) making the entire exercise pointless. */
+ if (arg_userns_ownership == USER_NAMESPACE_OWNERSHIP_CHOWN && arg_volatile_mode != VOLATILE_NO)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--volatile= and --private-users-ownership=chown may not be combined.");
+
+ /* If --network-namespace-path is given with any other network-related option (except --private-network),
+ * we need to error out, to avoid conflicts between different network options. */
+ if (arg_network_namespace_path &&
+ (arg_network_interfaces || arg_network_macvlan ||
+ arg_network_ipvlan || arg_network_veth_extra ||
+ arg_network_bridge || arg_network_zone ||
+ arg_network_veth))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--network-namespace-path= cannot be combined with other network options.");
+
+ if (arg_network_bridge && arg_network_zone)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "--network-bridge= and --network-zone= may not be combined.");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO && (arg_mount_settings & MOUNT_APPLY_APIVFS_NETNS) && !arg_private_network)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Invalid namespacing settings. Mounting sysfs with --private-users requires --private-network.");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO && !(arg_mount_settings & MOUNT_APPLY_APIVFS_RO))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot combine --private-users with read-write mounts.");
+
+ if (arg_expose_ports && !arg_private_network)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot use --port= without private networking.");
+
+ if (arg_caps_ambient) {
+ if (arg_caps_ambient == UINT64_MAX)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "AmbientCapability= does not support the value all.");
+
+ if ((arg_caps_ambient & arg_caps_retain) != arg_caps_ambient)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "AmbientCapability= setting is not fully covered by Capability= setting.");
+
+ if (arg_start_mode == START_BOOT)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "AmbientCapability= setting is not useful for boot mode.");
+ }
+
+ if (arg_userns_mode == USER_NAMESPACE_NO && !strv_isempty(arg_bind_user))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--bind-user= requires --private-users");
+
+ /* Drop duplicate --bind-user= entries */
+ strv_uniq(arg_bind_user);
+
+ r = custom_mount_check_all();
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int verify_network_interfaces_initialized(void) {
+ int r;
+ r = test_network_interfaces_initialized(arg_network_interfaces);
+ if (r < 0)
+ return r;
+
+ r = test_network_interfaces_initialized(arg_network_macvlan);
+ if (r < 0)
+ return r;
+
+ r = test_network_interfaces_initialized(arg_network_ipvlan);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+int userns_lchown(const char *p, uid_t uid, gid_t gid) {
+ assert(p);
+
+ if (arg_userns_mode == USER_NAMESPACE_NO)
+ return 0;
+
+ if (uid == UID_INVALID && gid == GID_INVALID)
+ return 0;
+
+ if (uid != UID_INVALID) {
+ uid += arg_uid_shift;
+
+ if (uid < arg_uid_shift || uid >= arg_uid_shift + arg_uid_range)
+ return -EOVERFLOW;
+ }
+
+ if (gid != GID_INVALID) {
+ gid += (gid_t) arg_uid_shift;
+
+ if (gid < (gid_t) arg_uid_shift || gid >= (gid_t) (arg_uid_shift + arg_uid_range))
+ return -EOVERFLOW;
+ }
+
+ return RET_NERRNO(lchown(p, uid, gid));
+}
+
+int userns_mkdir(const char *root, const char *path, mode_t mode, uid_t uid, gid_t gid) {
+ const char *q;
+ int r;
+
+ q = prefix_roota(root, path);
+ r = RET_NERRNO(mkdir(q, mode));
+ if (r == -EEXIST)
+ return 0;
+ if (r < 0)
+ return r;
+
+ return userns_lchown(q, uid, gid);
+}
+
+static const char *timezone_from_path(const char *path) {
+ return PATH_STARTSWITH_SET(
+ path,
+ "../usr/share/zoneinfo/",
+ "/usr/share/zoneinfo/");
+}
+
+static bool etc_writable(void) {
+ return !arg_read_only || IN_SET(arg_volatile_mode, VOLATILE_YES, VOLATILE_OVERLAY);
+}
+
+static int setup_timezone(const char *dest) {
+ _cleanup_free_ char *p = NULL, *etc = NULL;
+ const char *where, *check;
+ TimezoneMode m;
+ int r;
+
+ assert(dest);
+
+ if (IN_SET(arg_timezone, TIMEZONE_AUTO, TIMEZONE_SYMLINK)) {
+ r = readlink_malloc("/etc/localtime", &p);
+ if (r == -ENOENT && arg_timezone == TIMEZONE_AUTO)
+ m = etc_writable() ? TIMEZONE_DELETE : TIMEZONE_OFF;
+ else if (r == -EINVAL && arg_timezone == TIMEZONE_AUTO) /* regular file? */
+ m = etc_writable() ? TIMEZONE_COPY : TIMEZONE_BIND;
+ else if (r < 0) {
+ log_warning_errno(r, "Failed to read host's /etc/localtime symlink, not updating container timezone: %m");
+ /* To handle warning, delete /etc/localtime and replace it with a symbolic link to a time zone data
+ * file.
+ *
+ * Example:
+ * ln -s /usr/share/zoneinfo/UTC /etc/localtime
+ */
+ return 0;
+ } else if (arg_timezone == TIMEZONE_AUTO)
+ m = etc_writable() ? TIMEZONE_SYMLINK : TIMEZONE_BIND;
+ else
+ m = arg_timezone;
+ } else
+ m = arg_timezone;
+
+ if (m == TIMEZONE_OFF)
+ return 0;
+
+ r = chase("/etc", dest, CHASE_PREFIX_ROOT, &etc, NULL);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to resolve /etc path in container, ignoring: %m");
+ return 0;
+ }
+
+ where = strjoina(etc, "/localtime");
+
+ switch (m) {
+
+ case TIMEZONE_DELETE:
+ if (unlink(where) < 0)
+ log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_WARNING, errno, "Failed to remove '%s', ignoring: %m", where);
+
+ return 0;
+
+ case TIMEZONE_SYMLINK: {
+ _cleanup_free_ char *q = NULL;
+ const char *z, *what;
+
+ z = timezone_from_path(p);
+ if (!z) {
+ log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone.");
+ return 0;
+ }
+
+ r = readlink_malloc(where, &q);
+ if (r >= 0 && streq_ptr(timezone_from_path(q), z))
+ return 0; /* Already pointing to the right place? Then do nothing .. */
+
+ check = strjoina(dest, "/usr/share/zoneinfo/", z);
+ r = chase(check, dest, 0, NULL, NULL);
+ if (r < 0)
+ log_debug_errno(r, "Timezone %s does not exist (or is not accessible) in container, not creating symlink: %m", z);
+ else {
+ if (unlink(where) < 0 && errno != ENOENT) {
+ log_full_errno(IN_SET(errno, EROFS, EACCES, EPERM) ? LOG_DEBUG : LOG_WARNING, /* Don't complain on read-only images */
+ errno, "Failed to remove existing timezone info %s in container, ignoring: %m", where);
+ return 0;
+ }
+
+ what = strjoina("../usr/share/zoneinfo/", z);
+ if (symlink(what, where) < 0) {
+ log_full_errno(IN_SET(errno, EROFS, EACCES, EPERM) ? LOG_DEBUG : LOG_WARNING,
+ errno, "Failed to correct timezone of container, ignoring: %m");
+ return 0;
+ }
+
+ break;
+ }
+
+ _fallthrough_;
+ }
+
+ case TIMEZONE_BIND: {
+ _cleanup_free_ char *resolved = NULL;
+ int found;
+
+ found = chase(where, dest, CHASE_NONEXISTENT, &resolved, NULL);
+ if (found < 0) {
+ log_warning_errno(found, "Failed to resolve /etc/localtime path in container, ignoring: %m");
+ return 0;
+ }
+
+ if (found == 0) /* missing? */
+ (void) touch(resolved);
+
+ r = mount_nofollow_verbose(LOG_WARNING, "/etc/localtime", resolved, NULL, MS_BIND, NULL);
+ if (r >= 0)
+ return mount_nofollow_verbose(LOG_ERR, NULL, resolved, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NODEV, NULL);
+
+ _fallthrough_;
+ }
+
+ case TIMEZONE_COPY:
+ /* If mounting failed, try to copy */
+ r = copy_file_atomic("/etc/localtime", where, 0644, COPY_REFLINK|COPY_REPLACE);
+ if (r < 0) {
+ log_full_errno(IN_SET(r, -EROFS, -EACCES, -EPERM) ? LOG_DEBUG : LOG_WARNING, r,
+ "Failed to copy /etc/localtime to %s, ignoring: %m", where);
+ return 0;
+ }
+
+ break;
+
+ default:
+ assert_not_reached();
+ }
+
+ /* Fix permissions of the symlink or file copy we just created */
+ r = userns_lchown(where, 0, 0);
+ if (r < 0)
+ log_warning_errno(r, "Failed to chown /etc/localtime, ignoring: %m");
+
+ return 0;
+}
+
+static int have_resolv_conf(const char *path) {
+ assert(path);
+
+ if (access(path, F_OK) < 0) {
+ if (errno == ENOENT)
+ return 0;
+
+ return log_debug_errno(errno, "Failed to determine whether '%s' is available: %m", path);
+ }
+
+ return 1;
+}
+
+static int resolved_listening(void) {
+ _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+ _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+ _cleanup_free_ char *dns_stub_listener_mode = NULL;
+ int r;
+
+ /* Check if resolved is listening */
+
+ r = sd_bus_open_system(&bus);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to open system bus: %m");
+
+ r = bus_name_has_owner(bus, "org.freedesktop.resolve1", NULL);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to check whether the 'org.freedesktop.resolve1' bus name is taken: %m");
+ if (r == 0)
+ return 0;
+
+ r = bus_get_property_string(bus, bus_resolve_mgr, "DNSStubListener", &error, &dns_stub_listener_mode);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to query DNSStubListener property: %s", bus_error_message(&error, r));
+
+ return STR_IN_SET(dns_stub_listener_mode, "udp", "yes");
+}
+
+static int setup_resolv_conf(const char *dest) {
+ _cleanup_free_ char *etc = NULL;
+ const char *where, *what;
+ ResolvConfMode m;
+ int r;
+
+ assert(dest);
+
+ if (arg_resolv_conf == RESOLV_CONF_AUTO) {
+ if (arg_private_network)
+ m = RESOLV_CONF_OFF;
+ else if (have_resolv_conf(PRIVATE_STUB_RESOLV_CONF) > 0 && resolved_listening() > 0)
+ m = etc_writable() ? RESOLV_CONF_COPY_STUB : RESOLV_CONF_BIND_STUB;
+ else if (have_resolv_conf("/etc/resolv.conf") > 0)
+ m = etc_writable() ? RESOLV_CONF_COPY_HOST : RESOLV_CONF_BIND_HOST;
+ else
+ m = etc_writable() ? RESOLV_CONF_DELETE : RESOLV_CONF_OFF;
+
+ } else
+ m = arg_resolv_conf;
+
+ if (m == RESOLV_CONF_OFF)
+ return 0;
+
+ r = chase("/etc", dest, CHASE_PREFIX_ROOT, &etc, NULL);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to resolve /etc path in container, ignoring: %m");
+ return 0;
+ }
+
+ where = strjoina(etc, "/resolv.conf");
+
+ if (m == RESOLV_CONF_DELETE) {
+ if (unlink(where) < 0)
+ log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_WARNING, errno, "Failed to remove '%s', ignoring: %m", where);
+
+ return 0;
+ }
+
+ if (IN_SET(m, RESOLV_CONF_BIND_STATIC, RESOLV_CONF_REPLACE_STATIC, RESOLV_CONF_COPY_STATIC))
+ what = PRIVATE_STATIC_RESOLV_CONF;
+ else if (IN_SET(m, RESOLV_CONF_BIND_UPLINK, RESOLV_CONF_REPLACE_UPLINK, RESOLV_CONF_COPY_UPLINK))
+ what = PRIVATE_UPLINK_RESOLV_CONF;
+ else if (IN_SET(m, RESOLV_CONF_BIND_STUB, RESOLV_CONF_REPLACE_STUB, RESOLV_CONF_COPY_STUB))
+ what = PRIVATE_STUB_RESOLV_CONF;
+ else
+ what = "/etc/resolv.conf";
+
+ if (IN_SET(m, RESOLV_CONF_BIND_HOST, RESOLV_CONF_BIND_STATIC, RESOLV_CONF_BIND_UPLINK, RESOLV_CONF_BIND_STUB)) {
+ _cleanup_free_ char *resolved = NULL;
+ int found;
+
+ found = chase(where, dest, CHASE_NONEXISTENT|CHASE_NOFOLLOW, &resolved, NULL);
+ if (found < 0) {
+ log_warning_errno(found, "Failed to resolve /etc/resolv.conf path in container, ignoring: %m");
+ return 0;
+ }
+
+ if (found == 0) /* missing? */
+ (void) touch(resolved);
+
+ r = mount_nofollow_verbose(LOG_WARNING, what, resolved, NULL, MS_BIND, NULL);
+ if (r >= 0)
+ return mount_nofollow_verbose(LOG_ERR, NULL, resolved, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NODEV, NULL);
+
+ /* If that didn't work, let's copy the file */
+ }
+
+ if (IN_SET(m, RESOLV_CONF_REPLACE_HOST, RESOLV_CONF_REPLACE_STATIC, RESOLV_CONF_REPLACE_UPLINK, RESOLV_CONF_REPLACE_STUB))
+ r = copy_file_atomic(what, where, 0644, COPY_REFLINK|COPY_REPLACE);
+ else
+ r = copy_file(what, where, O_TRUNC|O_NOFOLLOW, 0644, COPY_REFLINK);
+ if (r < 0) {
+ /* If the file already exists as symlink, let's suppress the warning, under the assumption that
+ * resolved or something similar runs inside and the symlink points there.
+ *
+ * If the disk image is read-only, there's also no point in complaining.
+ */
+ log_full_errno(!IN_SET(RESOLV_CONF_COPY_HOST, RESOLV_CONF_COPY_STATIC, RESOLV_CONF_COPY_UPLINK, RESOLV_CONF_COPY_STUB) &&
+ IN_SET(r, -ELOOP, -EROFS, -EACCES, -EPERM) ? LOG_DEBUG : LOG_WARNING, r,
+ "Failed to copy /etc/resolv.conf to %s, ignoring: %m", where);
+ return 0;
+ }
+
+ r = userns_lchown(where, 0, 0);
+ if (r < 0)
+ log_warning_errno(r, "Failed to chown /etc/resolv.conf, ignoring: %m");
+
+ return 0;
+}
+
+static int setup_boot_id(void) {
+ _cleanup_(unlink_and_freep) char *from = NULL;
+ _cleanup_free_ char *path = NULL;
+ sd_id128_t rnd = SD_ID128_NULL;
+ const char *to;
+ int r;
+
+ /* Generate a new randomized boot ID, so that each boot-up of the container gets a new one */
+
+ r = tempfn_random_child("/run", "proc-sys-kernel-random-boot-id", &path);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate random boot ID path: %m");
+
+ r = sd_id128_randomize(&rnd);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate random boot id: %m");
+
+ r = id128_write(path, ID128_FORMAT_UUID, rnd);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write boot id: %m");
+
+ from = TAKE_PTR(path);
+ to = "/proc/sys/kernel/random/boot_id";
+
+ r = mount_nofollow_verbose(LOG_ERR, from, to, NULL, MS_BIND, NULL);
+ if (r < 0)
+ return r;
+
+ return mount_nofollow_verbose(LOG_ERR, NULL, to, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL);
+}
+
+static int copy_devnodes(const char *dest) {
+ static const char devnodes[] =
+ "null\0"
+ "zero\0"
+ "full\0"
+ "random\0"
+ "urandom\0"
+ "tty\0"
+ "net/tun\0";
+
+ int r = 0;
+
+ assert(dest);
+
+ BLOCK_WITH_UMASK(0000);
+
+ /* Create /dev/net, so that we can create /dev/net/tun in it */
+ if (userns_mkdir(dest, "/dev/net", 0755, 0, 0) < 0)
+ return log_error_errno(r, "Failed to create /dev/net directory: %m");
+
+ NULSTR_FOREACH(d, devnodes) {
+ _cleanup_free_ char *from = NULL, *to = NULL;
+ struct stat st;
+
+ from = path_join("/dev/", d);
+ if (!from)
+ return log_oom();
+
+ to = path_join(dest, from);
+ if (!to)
+ return log_oom();
+
+ if (stat(from, &st) < 0) {
+
+ if (errno != ENOENT)
+ return log_error_errno(errno, "Failed to stat %s: %m", from);
+
+ } else if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "%s is not a char or block device, cannot copy.", from);
+ else {
+ _cleanup_free_ char *sl = NULL, *prefixed = NULL, *dn = NULL, *t = NULL;
+
+ if (mknod(to, st.st_mode, st.st_rdev) < 0) {
+ /* Explicitly warn the user when /dev is already populated. */
+ if (errno == EEXIST)
+ log_notice("%s/dev is pre-mounted and pre-populated. If a pre-mounted /dev is provided it needs to be an unpopulated file system.", dest);
+ if (errno != EPERM)
+ return log_error_errno(errno, "mknod(%s) failed: %m", to);
+
+ /* Some systems abusively restrict mknod but allow bind mounts. */
+ r = touch(to);
+ if (r < 0)
+ return log_error_errno(r, "touch (%s) failed: %m", to);
+ r = mount_nofollow_verbose(LOG_DEBUG, from, to, NULL, MS_BIND, NULL);
+ if (r < 0)
+ return log_error_errno(r, "Both mknod and bind mount (%s) failed: %m", to);
+ }
+
+ r = userns_lchown(to, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "chown() of device node %s failed: %m", to);
+
+ dn = path_join("/dev", S_ISCHR(st.st_mode) ? "char" : "block");
+ if (!dn)
+ return log_oom();
+
+ r = userns_mkdir(dest, dn, 0755, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create '%s': %m", dn);
+
+ if (asprintf(&sl, "%s/%u:%u", dn, major(st.st_rdev), minor(st.st_rdev)) < 0)
+ return log_oom();
+
+ prefixed = path_join(dest, sl);
+ if (!prefixed)
+ return log_oom();
+
+ t = path_join("..", d);
+ if (!t)
+ return log_oom();
+
+ if (symlink(t, prefixed) < 0)
+ log_debug_errno(errno, "Failed to symlink '%s' to '%s': %m", t, prefixed);
+ }
+ }
+
+ return r;
+}
+
+static int make_extra_nodes(const char *dest) {
+ size_t i;
+ int r;
+
+ BLOCK_WITH_UMASK(0000);
+
+ for (i = 0; i < arg_n_extra_nodes; i++) {
+ _cleanup_free_ char *path = NULL;
+ DeviceNode *n = arg_extra_nodes + i;
+
+ path = path_join(dest, n->path);
+ if (!path)
+ return log_oom();
+
+ if (mknod(path, n->mode, S_ISCHR(n->mode) || S_ISBLK(n->mode) ? makedev(n->major, n->minor) : 0) < 0)
+ return log_error_errno(errno, "Failed to create device node '%s': %m", path);
+
+ r = chmod_and_chown(path, n->mode, n->uid, n->gid);
+ if (r < 0)
+ return log_error_errno(r, "Failed to adjust device node ownership of '%s': %m", path);
+ }
+
+ return 0;
+}
+
+static int setup_pts(const char *dest) {
+ _cleanup_free_ char *options = NULL;
+ const char *p;
+ int r;
+
+#if HAVE_SELINUX
+ if (arg_selinux_apifs_context)
+ (void) asprintf(&options,
+ "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT ",context=\"%s\"",
+ arg_uid_shift + TTY_GID,
+ arg_selinux_apifs_context);
+ else
+#endif
+ (void) asprintf(&options,
+ "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT,
+ arg_uid_shift + TTY_GID);
+
+ if (!options)
+ return log_oom();
+
+ /* Mount /dev/pts itself */
+ p = prefix_roota(dest, "/dev/pts");
+ r = RET_NERRNO(mkdir(p, 0755));
+ if (r < 0)
+ return log_error_errno(r, "Failed to create /dev/pts: %m");
+
+ r = mount_nofollow_verbose(LOG_ERR, "devpts", p, "devpts", MS_NOSUID|MS_NOEXEC, options);
+ if (r < 0)
+ return r;
+ r = userns_lchown(p, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to chown /dev/pts: %m");
+
+ /* Create /dev/ptmx symlink */
+ p = prefix_roota(dest, "/dev/ptmx");
+ if (symlink("pts/ptmx", p) < 0)
+ return log_error_errno(errno, "Failed to create /dev/ptmx symlink: %m");
+ r = userns_lchown(p, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to chown /dev/ptmx: %m");
+
+ /* And fix /dev/pts/ptmx ownership */
+ p = prefix_roota(dest, "/dev/pts/ptmx");
+ r = userns_lchown(p, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to chown /dev/pts/ptmx: %m");
+
+ return 0;
+}
+
+static int setup_stdio_as_dev_console(void) {
+ _cleanup_close_ int terminal = -EBADF;
+ int r;
+
+ /* We open the TTY in O_NOCTTY mode, so that we do not become controller yet. We'll do that later
+ * explicitly, if we are configured to. */
+ terminal = open_terminal("/dev/console", O_RDWR|O_NOCTTY);
+ if (terminal < 0)
+ return log_error_errno(terminal, "Failed to open console: %m");
+
+ /* Make sure we can continue logging to the original stderr, even if
+ * stderr points elsewhere now */
+ r = log_dup_console();
+ if (r < 0)
+ return log_error_errno(r, "Failed to duplicate stderr: %m");
+
+ /* invalidates 'terminal' on success and failure */
+ r = rearrange_stdio(terminal, terminal, terminal);
+ TAKE_FD(terminal);
+ if (r < 0)
+ return log_error_errno(r, "Failed to move console to stdin/stdout/stderr: %m");
+
+ return 0;
+}
+
+static int setup_dev_console(const char *console) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ /* Create /dev/console symlink */
+ r = path_make_relative("/dev", console, &p);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create relative path: %m");
+
+ if (symlink(p, "/dev/console") < 0)
+ return log_error_errno(errno, "Failed to create /dev/console symlink: %m");
+
+ return 0;
+}
+
+static int setup_keyring(void) {
+ key_serial_t keyring;
+
+ /* Allocate a new session keyring for the container. This makes sure the keyring of the session
+ * systemd-nspawn was invoked from doesn't leak into the container. Note that by default we block
+ * keyctl() and request_key() anyway via seccomp so doing this operation isn't strictly necessary,
+ * but in case people explicitly allow-list these system calls let's make sure we don't leak anything
+ * into the container. */
+
+ keyring = keyctl(KEYCTL_JOIN_SESSION_KEYRING, 0, 0, 0, 0);
+ if (keyring == -1) {
+ if (errno == ENOSYS)
+ log_debug_errno(errno, "Kernel keyring not supported, ignoring.");
+ else if (ERRNO_IS_PRIVILEGE(errno))
+ log_debug_errno(errno, "Kernel keyring access prohibited, ignoring.");
+ else
+ return log_error_errno(errno, "Setting up kernel keyring failed: %m");
+ }
+
+ return 0;
+}
+
+static int setup_credentials(const char *root) {
+ const char *q;
+ int r;
+
+ if (arg_n_credentials <= 0)
+ return 0;
+
+ r = userns_mkdir(root, "/run/host", 0755, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create /run/host: %m");
+
+ r = userns_mkdir(root, "/run/host/credentials", 0700, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create /run/host/credentials: %m");
+
+ q = prefix_roota(root, "/run/host/credentials");
+ r = mount_nofollow_verbose(LOG_ERR, NULL, q, "ramfs", MS_NOSUID|MS_NOEXEC|MS_NODEV, "mode=0700");
+ if (r < 0)
+ return r;
+
+ for (size_t i = 0; i < arg_n_credentials; i++) {
+ _cleanup_free_ char *j = NULL;
+ _cleanup_close_ int fd = -EBADF;
+
+ j = path_join(q, arg_credentials[i].id);
+ if (!j)
+ return log_oom();
+
+ fd = open(j, O_CREAT|O_EXCL|O_WRONLY|O_CLOEXEC|O_NOFOLLOW, 0600);
+ if (fd < 0)
+ return log_error_errno(errno, "Failed to create credential file %s: %m", j);
+
+ r = loop_write(fd, arg_credentials[i].data, arg_credentials[i].size);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write credential to file %s: %m", j);
+
+ if (fchmod(fd, 0400) < 0)
+ return log_error_errno(errno, "Failed to adjust access mode of %s: %m", j);
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ if (fchown(fd, arg_uid_shift, arg_uid_shift) < 0)
+ return log_error_errno(errno, "Failed to adjust ownership of %s: %m", j);
+ }
+ }
+
+ if (chmod(q, 0500) < 0)
+ return log_error_errno(errno, "Failed to adjust access mode of %s: %m", q);
+
+ r = userns_lchown(q, 0, 0);
+ if (r < 0)
+ return r;
+
+ /* Make both mount and superblock read-only now */
+ r = mount_nofollow_verbose(LOG_ERR, NULL, q, NULL, MS_REMOUNT|MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL);
+ if (r < 0)
+ return r;
+
+ return mount_nofollow_verbose(LOG_ERR, NULL, q, NULL, MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, "mode=0500");
+}
+
+static int setup_kmsg(int fd_inner_socket) {
+ _cleanup_(unlink_and_freep) char *from = NULL;
+ _cleanup_free_ char *fifo = NULL;
+ _cleanup_close_ int fd = -EBADF;
+ int r;
+
+ assert(fd_inner_socket >= 0);
+
+ BLOCK_WITH_UMASK(0000);
+
+ /* We create the kmsg FIFO as a temporary file in /run, but immediately delete it after bind mounting it to
+ * /proc/kmsg. While FIFOs on the reading side behave very similar to /proc/kmsg, their writing side behaves
+ * differently from /dev/kmsg in that writing blocks when nothing is reading. In order to avoid any problems
+ * with containers deadlocking due to this we simply make /dev/kmsg unavailable to the container. */
+
+ r = tempfn_random_child("/run", "proc-kmsg", &fifo);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate kmsg path: %m");
+
+ if (mkfifo(fifo, 0600) < 0)
+ return log_error_errno(errno, "mkfifo() for /run/kmsg failed: %m");
+
+ from = TAKE_PTR(fifo);
+
+ r = mount_nofollow_verbose(LOG_ERR, from, "/proc/kmsg", NULL, MS_BIND, NULL);
+ if (r < 0)
+ return r;
+
+ fd = open(from, O_RDWR|O_NONBLOCK|O_CLOEXEC);
+ if (fd < 0)
+ return log_error_errno(errno, "Failed to open fifo: %m");
+
+ /* Store away the fd in the socket, so that it stays open as long as we run the child */
+ r = send_one_fd(fd_inner_socket, fd, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to send FIFO fd: %m");
+
+ return 0;
+}
+
+struct ExposeArgs {
+ union in_addr_union address4;
+ union in_addr_union address6;
+ struct FirewallContext *fw_ctx;
+};
+
+static int on_address_change(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {
+ struct ExposeArgs *args = ASSERT_PTR(userdata);
+
+ assert(rtnl);
+ assert(m);
+
+ (void) expose_port_execute(rtnl, &args->fw_ctx, arg_expose_ports, AF_INET, &args->address4);
+ (void) expose_port_execute(rtnl, &args->fw_ctx, arg_expose_ports, AF_INET6, &args->address6);
+ return 0;
+}
+
+static int setup_hostname(void) {
+ int r;
+
+ if ((arg_clone_ns_flags & CLONE_NEWUTS) == 0)
+ return 0;
+
+ r = sethostname_idempotent(arg_hostname ?: arg_machine);
+ if (r < 0)
+ return log_error_errno(r, "Failed to set hostname: %m");
+
+ return 0;
+}
+
+static int setup_journal(const char *directory) {
+ _cleanup_free_ char *d = NULL;
+ const char *p, *q;
+ sd_id128_t this_id;
+ bool try;
+ int r;
+
+ /* Don't link journals in ephemeral mode */
+ if (arg_ephemeral)
+ return 0;
+
+ if (arg_link_journal == LINK_NO)
+ return 0;
+
+ try = arg_link_journal_try || arg_link_journal == LINK_AUTO;
+
+ r = sd_id128_get_machine(&this_id);
+ if (r < 0)
+ return log_error_errno(r, "Failed to retrieve machine ID: %m");
+
+ if (sd_id128_equal(arg_uuid, this_id)) {
+ log_full(try ? LOG_WARNING : LOG_ERR,
+ "Host and machine ids are equal (%s): refusing to link journals", SD_ID128_TO_STRING(arg_uuid));
+ if (try)
+ return 0;
+ return -EEXIST;
+ }
+
+ FOREACH_STRING(dirname, "/var", "/var/log", "/var/log/journal") {
+ r = userns_mkdir(directory, dirname, 0755, 0, 0);
+ if (r < 0) {
+ bool ignore = r == -EROFS && try;
+ log_full_errno(ignore ? LOG_DEBUG : LOG_ERR, r,
+ "Failed to create %s%s: %m", dirname, ignore ? ", ignoring" : "");
+ return ignore ? 0 : r;
+ }
+ }
+
+ p = strjoina("/var/log/journal/", SD_ID128_TO_STRING(arg_uuid));
+ q = prefix_roota(directory, p);
+
+ if (path_is_mount_point(p, NULL, 0) > 0) {
+ if (try)
+ return 0;
+
+ return log_error_errno(SYNTHETIC_ERRNO(EEXIST),
+ "%s: already a mount point, refusing to use for journal", p);
+ }
+
+ if (path_is_mount_point(q, NULL, 0) > 0) {
+ if (try)
+ return 0;
+
+ return log_error_errno(SYNTHETIC_ERRNO(EEXIST),
+ "%s: already a mount point, refusing to use for journal", q);
+ }
+
+ r = readlink_and_make_absolute(p, &d);
+ if (r >= 0) {
+ if (IN_SET(arg_link_journal, LINK_GUEST, LINK_AUTO) &&
+ path_equal(d, q)) {
+
+ r = userns_mkdir(directory, p, 0755, 0, 0);
+ if (r < 0)
+ log_warning_errno(r, "Failed to create directory %s: %m", q);
+ return 0;
+ }
+
+ if (unlink(p) < 0)
+ return log_error_errno(errno, "Failed to remove symlink %s: %m", p);
+ } else if (r == -EINVAL) {
+
+ if (arg_link_journal == LINK_GUEST &&
+ rmdir(p) < 0) {
+
+ if (errno == ENOTDIR) {
+ log_error("%s already exists and is neither a symlink nor a directory", p);
+ return r;
+ } else
+ return log_error_errno(errno, "Failed to remove %s: %m", p);
+ }
+ } else if (r != -ENOENT)
+ return log_error_errno(r, "readlink(%s) failed: %m", p);
+
+ if (arg_link_journal == LINK_GUEST) {
+
+ if (symlink(q, p) < 0) {
+ if (try) {
+ log_debug_errno(errno, "Failed to symlink %s to %s, skipping journal setup: %m", q, p);
+ return 0;
+ } else
+ return log_error_errno(errno, "Failed to symlink %s to %s: %m", q, p);
+ }
+
+ r = userns_mkdir(directory, p, 0755, 0, 0);
+ if (r < 0)
+ log_warning_errno(r, "Failed to create directory %s: %m", q);
+ return 0;
+ }
+
+ if (arg_link_journal == LINK_HOST) {
+ /* don't create parents here — if the host doesn't have
+ * permanent journal set up, don't force it here */
+
+ r = RET_NERRNO(mkdir(p, 0755));
+ if (r < 0 && r != -EEXIST) {
+ if (try) {
+ log_debug_errno(r, "Failed to create %s, skipping journal setup: %m", p);
+ return 0;
+ } else
+ return log_error_errno(r, "Failed to create %s: %m", p);
+ }
+
+ } else if (access(p, F_OK) < 0)
+ return 0;
+
+ if (dir_is_empty(q, /* ignore_hidden_or_backup= */ false) == 0)
+ log_warning("%s is not empty, proceeding anyway.", q);
+
+ r = userns_mkdir(directory, p, 0755, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create %s: %m", q);
+
+ r = mount_nofollow_verbose(LOG_DEBUG, p, q, NULL, MS_BIND, NULL);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to bind mount journal from host into guest: %m");
+
+ return 0;
+}
+
+static int drop_capabilities(uid_t uid) {
+ CapabilityQuintet q;
+
+ /* Let's initialize all five capability sets to something valid. If the quintet was configured via
+ * OCI use that, but fill in missing bits. If it wasn't then derive the quintet in full from
+ * arg_caps_retain. */
+
+ if (capability_quintet_is_set(&arg_full_capabilities)) {
+ q = arg_full_capabilities;
+
+ if (q.bounding == UINT64_MAX)
+ q.bounding = uid == 0 ? arg_caps_retain : 0;
+
+ if (q.effective == UINT64_MAX)
+ q.effective = uid == 0 ? q.bounding : 0;
+
+ if (q.inheritable == UINT64_MAX)
+ q.inheritable = uid == 0 ? q.bounding : arg_caps_ambient;
+
+ if (q.permitted == UINT64_MAX)
+ q.permitted = uid == 0 ? q.bounding : arg_caps_ambient;
+
+ if (q.ambient == UINT64_MAX && ambient_capabilities_supported())
+ q.ambient = arg_caps_ambient;
+
+ if (capability_quintet_mangle(&q))
+ return log_error_errno(SYNTHETIC_ERRNO(EPERM), "Cannot set capabilities that are not in the current bounding set.");
+
+ } else {
+ q = (CapabilityQuintet) {
+ .bounding = arg_caps_retain,
+ .effective = uid == 0 ? arg_caps_retain : 0,
+ .inheritable = uid == 0 ? arg_caps_retain : arg_caps_ambient,
+ .permitted = uid == 0 ? arg_caps_retain : arg_caps_ambient,
+ .ambient = ambient_capabilities_supported() ? arg_caps_ambient : UINT64_MAX,
+ };
+
+ /* If we're not using OCI, proceed with mangled capabilities (so we don't error out)
+ * in order to maintain the same behavior as systemd < 242. */
+ if (capability_quintet_mangle(&q))
+ log_full(arg_quiet ? LOG_DEBUG : LOG_WARNING,
+ "Some capabilities will not be set because they are not in the current bounding set.");
+
+ }
+
+ return capability_quintet_enforce(&q);
+}
+
+static int reset_audit_loginuid(void) {
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ if ((arg_clone_ns_flags & CLONE_NEWPID) == 0)
+ return 0;
+
+ r = read_one_line_file("/proc/self/loginuid", &p);
+ if (r == -ENOENT)
+ return 0;
+ if (r < 0)
+ return log_error_errno(r, "Failed to read /proc/self/loginuid: %m");
+
+ /* Already reset? */
+ if (streq(p, "4294967295"))
+ return 0;
+
+ r = write_string_file("/proc/self/loginuid", "4294967295", WRITE_STRING_FILE_DISABLE_BUFFER);
+ if (r < 0) {
+ log_error_errno(r,
+ "Failed to reset audit login UID. This probably means that your kernel is too\n"
+ "old and you have audit enabled. Note that the auditing subsystem is known to\n"
+ "be incompatible with containers on old kernels. Please make sure to upgrade\n"
+ "your kernel or to off auditing with 'audit=0' on the kernel command line before\n"
+ "using systemd-nspawn. Sleeping for 5s... (%m)");
+
+ sleep(5);
+ }
+
+ return 0;
+}
+
+static int mount_tunnel_dig(const char *root) {
+ const char *p, *q;
+ int r;
+
+ (void) mkdir_p("/run/systemd/nspawn/", 0755);
+ (void) mkdir_p("/run/systemd/nspawn/propagate", 0600);
+ p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
+ (void) mkdir_p(p, 0600);
+
+ r = userns_mkdir(root, "/run/host", 0755, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create /run/host: %m");
+
+ r = userns_mkdir(root, NSPAWN_MOUNT_TUNNEL, 0600, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create "NSPAWN_MOUNT_TUNNEL": %m");
+
+ q = prefix_roota(root, NSPAWN_MOUNT_TUNNEL);
+ r = mount_nofollow_verbose(LOG_ERR, p, q, NULL, MS_BIND, NULL);
+ if (r < 0)
+ return r;
+
+ r = mount_nofollow_verbose(LOG_ERR, NULL, q, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY, NULL);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int mount_tunnel_open(void) {
+ int r;
+
+ r = mount_follow_verbose(LOG_ERR, NULL, NSPAWN_MOUNT_TUNNEL, NULL, MS_SLAVE, NULL);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
+static int setup_machine_id(const char *directory) {
+ int r;
+
+ /* If the UUID in the container is already set, then that's what counts, and we use. If it isn't set, and the
+ * caller passed --uuid=, then we'll pass it in the $container_uuid env var to PID 1 of the container. The
+ * assumption is that PID 1 will then write it to /etc/machine-id to make it persistent. If --uuid= is not
+ * passed we generate a random UUID, and pass it via $container_uuid. In effect this means that /etc/machine-id
+ * in the container and our idea of the container UUID will always be in sync (at least if PID 1 in the
+ * container behaves nicely). */
+
+ r = id128_get_machine(directory, &arg_uuid);
+ if (ERRNO_IS_NEG_MACHINE_ID_UNSET(r)) {
+ /* If the file is missing, empty, or uninitialized, we don't mind */
+ if (sd_id128_is_null(arg_uuid)) {
+ r = sd_id128_randomize(&arg_uuid);
+ if (r < 0)
+ return log_error_errno(r, "Failed to acquire randomized machine UUID: %m");
+ }
+ } else if (r < 0)
+ return log_error_errno(r, "Failed to read machine ID from container image: %m");
+
+ return 0;
+}
+
+static int recursive_chown(const char *directory, uid_t shift, uid_t range) {
+ int r;
+
+ assert(directory);
+
+ if (arg_userns_mode == USER_NAMESPACE_NO || arg_userns_ownership != USER_NAMESPACE_OWNERSHIP_CHOWN)
+ return 0;
+
+ r = path_patch_uid(directory, arg_uid_shift, arg_uid_range);
+ if (r == -EOPNOTSUPP)
+ return log_error_errno(r, "Automatic UID/GID adjusting is only supported for UID/GID ranges starting at multiples of 2^16 with a range of 2^16.");
+ if (r == -EBADE)
+ return log_error_errno(r, "Upper 16 bits of root directory UID and GID do not match.");
+ if (r < 0)
+ return log_error_errno(r, "Failed to adjust UID/GID shift of OS tree: %m");
+ if (r == 0)
+ log_debug("Root directory of image is already owned by the right UID/GID range, skipping recursive chown operation.");
+ else
+ log_debug("Patched directory tree to match UID/GID range.");
+
+ return r;
+}
+
+/*
+ * Return values:
+ * < 0 : wait_for_terminate() failed to get the state of the
+ * container, the container was terminated by a signal, or
+ * failed for an unknown reason. No change is made to the
+ * container argument.
+ * > 0 : The program executed in the container terminated with an
+ * error. The exit code of the program executed in the
+ * container is returned. The container argument has been set
+ * to CONTAINER_TERMINATED.
+ * 0 : The container is being rebooted, has been shut down or exited
+ * successfully. The container argument has been set to either
+ * CONTAINER_TERMINATED or CONTAINER_REBOOTED.
+ *
+ * That is, success is indicated by a return value of zero, and an
+ * error is indicated by a non-zero value.
+ */
+static int wait_for_container(pid_t pid, ContainerStatus *container) {
+ siginfo_t status;
+ int r;
+
+ r = wait_for_terminate(pid, &status);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to wait for container: %m");
+
+ switch (status.si_code) {
+
+ case CLD_EXITED:
+ if (status.si_status == 0)
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s exited successfully.", arg_machine);
+ else
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s failed with error code %i.", arg_machine, status.si_status);
+
+ *container = CONTAINER_TERMINATED;
+ return status.si_status;
+
+ case CLD_KILLED:
+ if (status.si_status == SIGINT) {
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s has been shut down.", arg_machine);
+ *container = CONTAINER_TERMINATED;
+ return 0;
+
+ } else if (status.si_status == SIGHUP) {
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s is being rebooted.", arg_machine);
+ *container = CONTAINER_REBOOTED;
+ return 0;
+ }
+
+ _fallthrough_;
+ case CLD_DUMPED:
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status));
+
+ default:
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Container %s failed due to unknown reason.", arg_machine);
+ }
+}
+
+static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
+ pid_t pid;
+
+ pid = PTR_TO_PID(userdata);
+ if (pid > 0) {
+ if (kill(pid, arg_kill_signal) >= 0) {
+ log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
+ sd_event_source_set_userdata(s, NULL);
+ return 0;
+ }
+ }
+
+ sd_event_exit(sd_event_source_get_event(s), 0);
+ return 0;
+}
+
+static int on_sigchld(sd_event_source *s, const struct signalfd_siginfo *ssi, void *userdata) {
+ pid_t pid;
+
+ assert(s);
+ assert(ssi);
+
+ pid = PTR_TO_PID(userdata);
+
+ for (;;) {
+ siginfo_t si = {};
+
+ if (waitid(P_ALL, 0, &si, WNOHANG|WNOWAIT|WEXITED) < 0)
+ return log_error_errno(errno, "Failed to waitid(): %m");
+ if (si.si_pid == 0) /* No pending children. */
+ break;
+ if (si.si_pid == pid) {
+ /* The main process we care for has exited. Return from
+ * signal handler but leave the zombie. */
+ sd_event_exit(sd_event_source_get_event(s), 0);
+ break;
+ }
+
+ /* Reap all other children. */
+ (void) waitid(P_PID, si.si_pid, &si, WNOHANG|WEXITED);
+ }
+
+ return 0;
+}
+
+static int on_request_stop(sd_bus_message *m, void *userdata, sd_bus_error *error) {
+ pid_t pid;
+
+ assert(m);
+
+ pid = PTR_TO_PID(userdata);
+
+ if (arg_kill_signal > 0) {
+ log_info("Container termination requested. Attempting to halt container.");
+ (void) kill(pid, arg_kill_signal);
+ } else {
+ log_info("Container termination requested. Exiting.");
+ sd_event_exit(sd_bus_get_event(sd_bus_message_get_bus(m)), 0);
+ }
+
+ return 0;
+}
+
+static int determine_names(void) {
+ int r;
+
+ if (arg_template && !arg_directory && arg_machine) {
+
+ /* If --template= was specified then we should not
+ * search for a machine, but instead create a new one
+ * in /var/lib/machine. */
+
+ arg_directory = path_join("/var/lib/machines", arg_machine);
+ if (!arg_directory)
+ return log_oom();
+ }
+
+ if (!arg_image && !arg_directory) {
+ if (arg_machine) {
+ _cleanup_(image_unrefp) Image *i = NULL;
+
+ r = image_find(IMAGE_MACHINE, arg_machine, NULL, &i);
+ if (r == -ENOENT)
+ return log_error_errno(r, "No image for machine '%s'.", arg_machine);
+ if (r < 0)
+ return log_error_errno(r, "Failed to find image for machine '%s': %m", arg_machine);
+
+ if (IN_SET(i->type, IMAGE_RAW, IMAGE_BLOCK))
+ r = free_and_strdup(&arg_image, i->path);
+ else
+ r = free_and_strdup(&arg_directory, i->path);
+ if (r < 0)
+ return log_oom();
+
+ if (!arg_ephemeral)
+ arg_read_only = arg_read_only || i->read_only;
+ } else {
+ r = safe_getcwd(&arg_directory);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine current directory: %m");
+ }
+
+ if (!arg_directory && !arg_image)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to determine path, please use -D or -i.");
+ }
+
+ if (!arg_machine) {
+ if (arg_directory && path_equal(arg_directory, "/"))
+ arg_machine = gethostname_malloc();
+ else if (arg_image) {
+ char *e;
+
+ r = path_extract_filename(arg_image, &arg_machine);
+ if (r < 0)
+ return log_error_errno(r, "Failed to extract file name from '%s': %m", arg_image);
+
+ /* Truncate suffix if there is one */
+ e = endswith(arg_machine, ".raw");
+ if (e)
+ *e = 0;
+ } else {
+ r = path_extract_filename(arg_directory, &arg_machine);
+ if (r < 0)
+ return log_error_errno(r, "Failed to extract file name from '%s': %m", arg_directory);
+ }
+
+ hostname_cleanup(arg_machine);
+ if (!hostname_is_valid(arg_machine, 0))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Failed to determine machine name automatically, please use -M.");
+
+ /* Copy the machine name before the random suffix is added below, otherwise we won't be able
+ * to match fixed config file names. */
+ arg_settings_filename = strjoin(arg_machine, ".nspawn");
+ if (!arg_settings_filename)
+ return log_oom();
+
+ /* Add a random suffix when this is an ephemeral machine, so that we can run many
+ * instances at once without manually having to specify -M each time. */
+ if (arg_ephemeral)
+ if (strextendf(&arg_machine, "-%016" PRIx64, random_u64()) < 0)
+ return log_oom();
+ } else {
+ arg_settings_filename = strjoin(arg_machine, ".nspawn");
+ if (!arg_settings_filename)
+ return log_oom();
+ }
+
+ return 0;
+}
+
+static int chase_and_update(char **p, unsigned flags) {
+ char *chased;
+ int r;
+
+ assert(p);
+
+ if (!*p)
+ return 0;
+
+ r = chase(*p, NULL, flags, &chased, NULL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to resolve path %s: %m", *p);
+
+ return free_and_replace(*p, chased);
+}
+
+static int determine_uid_shift(const char *directory) {
+
+ if (arg_userns_mode == USER_NAMESPACE_NO) {
+ arg_uid_shift = 0;
+ return 0;
+ }
+
+ if (arg_uid_shift == UID_INVALID) {
+ struct stat st;
+
+ /* Read the UID shift off the image. Maybe we can reuse this to avoid chowning. */
+
+ if (stat(directory, &st) < 0)
+ return log_error_errno(errno, "Failed to determine UID base of %s: %m", directory);
+
+ arg_uid_shift = st.st_uid & UINT32_C(0xffff0000);
+
+ if (arg_uid_shift != (st.st_gid & UINT32_C(0xffff0000)))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "UID and GID base of %s don't match.", directory);
+
+ arg_uid_range = UINT32_C(0x10000);
+
+ if (arg_uid_shift != 0) {
+ /* If the image is shifted already, then we'll fall back to classic chowning, for
+ * compatibility (and simplicity), or refuse if mapping is explicitly requested. */
+
+ if (arg_userns_ownership == USER_NAMESPACE_OWNERSHIP_AUTO) {
+ log_debug("UID base of %s is non-zero, not using UID mapping.", directory);
+ arg_userns_ownership = USER_NAMESPACE_OWNERSHIP_CHOWN;
+ } else if (arg_userns_ownership == USER_NAMESPACE_OWNERSHIP_MAP)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "UID base of %s is not zero, UID mapping not supported.", directory);
+ }
+ }
+
+ if (!userns_shift_range_valid(arg_uid_shift, arg_uid_range))
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "UID base too high for UID range.");
+
+ return 0;
+}
+
+static unsigned long effective_clone_ns_flags(void) {
+ unsigned long flags = arg_clone_ns_flags;
+
+ if (arg_private_network)
+ flags |= CLONE_NEWNET;
+ if (arg_use_cgns)
+ flags |= CLONE_NEWCGROUP;
+ if (arg_userns_mode != USER_NAMESPACE_NO)
+ flags |= CLONE_NEWUSER;
+
+ return flags;
+}
+
+static int patch_sysctl(void) {
+
+ /* This table is inspired by runc's sysctl() function */
+ static const struct {
+ const char *key;
+ bool prefix;
+ unsigned long clone_flags;
+ } safe_sysctl[] = {
+ { "kernel.hostname", false, CLONE_NEWUTS },
+ { "kernel.domainname", false, CLONE_NEWUTS },
+ { "kernel.msgmax", false, CLONE_NEWIPC },
+ { "kernel.msgmnb", false, CLONE_NEWIPC },
+ { "kernel.msgmni", false, CLONE_NEWIPC },
+ { "kernel.sem", false, CLONE_NEWIPC },
+ { "kernel.shmall", false, CLONE_NEWIPC },
+ { "kernel.shmmax", false, CLONE_NEWIPC },
+ { "kernel.shmmni", false, CLONE_NEWIPC },
+ { "fs.mqueue.", true, CLONE_NEWIPC },
+ { "net.", true, CLONE_NEWNET },
+ };
+
+ unsigned long flags;
+ int r;
+
+ flags = effective_clone_ns_flags();
+
+ STRV_FOREACH_PAIR(k, v, arg_sysctl) {
+ bool good = false;
+ size_t i;
+
+ for (i = 0; i < ELEMENTSOF(safe_sysctl); i++) {
+
+ if (!FLAGS_SET(flags, safe_sysctl[i].clone_flags))
+ continue;
+
+ if (safe_sysctl[i].prefix)
+ good = startswith(*k, safe_sysctl[i].key);
+ else
+ good = streq(*k, safe_sysctl[i].key);
+
+ if (good)
+ break;
+ }
+
+ if (!good)
+ return log_error_errno(SYNTHETIC_ERRNO(EPERM), "Refusing to write to sysctl '%s', as it is not safe in the selected namespaces.", *k);
+
+ r = sysctl_write(*k, *v);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write sysctl '%s': %m", *k);
+ }
+
+ return 0;
+}
+
+static int inner_child(
+ Barrier *barrier,
+ int fd_inner_socket,
+ FDSet *fds,
+ char **os_release_pairs) {
+
+ _cleanup_free_ char *home = NULL;
+ size_t n_env = 1;
+ char *envp[] = {
+ (char*) "PATH=" DEFAULT_PATH_COMPAT,
+ NULL, /* container */
+ NULL, /* TERM */
+ NULL, /* HOME */
+ NULL, /* USER */
+ NULL, /* LOGNAME */
+ NULL, /* container_uuid */
+ NULL, /* LISTEN_FDS */
+ NULL, /* LISTEN_PID */
+ NULL, /* NOTIFY_SOCKET */
+ NULL, /* CREDENTIALS_DIRECTORY */
+ NULL, /* LANG */
+ NULL
+ };
+ const char *exec_target;
+ _cleanup_strv_free_ char **env_use = NULL;
+ int r, which_failed;
+
+ /* This is the "inner" child process, i.e. the one forked off by the "outer" child process, which is the one
+ * the container manager itself forked off. At the time of clone() it gained its own CLONE_NEWNS, CLONE_NEWPID,
+ * CLONE_NEWUTS, CLONE_NEWIPC, CLONE_NEWUSER namespaces. Note that it has its own CLONE_NEWNS namespace,
+ * separate from the CLONE_NEWNS created for the "outer" child, and also separate from the host's CLONE_NEWNS
+ * namespace. The reason for having two levels of CLONE_NEWNS namespaces is that the "inner" one is owned by
+ * the CLONE_NEWUSER namespace of the container, while the "outer" one is owned by the host's CLONE_NEWUSER
+ * namespace.
+ *
+ * Note at this point we have no CLONE_NEWNET namespace yet. We'll acquire that one later through
+ * unshare(). See below. */
+
+ assert(barrier);
+ assert(fd_inner_socket >= 0);
+
+ log_debug("Inner child is initializing.");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ /* Tell the parent, that it now can write the UID map. */
+ (void) barrier_place(barrier); /* #1 */
+
+ /* Wait until the parent wrote the UID map */
+ if (!barrier_place_and_sync(barrier)) /* #2 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Parent died too early");
+
+ /* Become the new root user inside our namespace */
+ r = reset_uid_gid();
+ if (r < 0)
+ return log_error_errno(r, "Couldn't become new root: %m");
+
+ /* Creating a new user namespace means all MS_SHARED mounts become MS_SLAVE. Let's put them
+ * back to MS_SHARED here, since that's what we want as defaults. (This will not reconnect
+ * propagation, but simply create new peer groups for all our mounts). */
+ r = mount_follow_verbose(LOG_ERR, NULL, "/", NULL, MS_SHARED|MS_REC, NULL);
+ if (r < 0)
+ return r;
+ }
+
+ r = mount_all(NULL,
+ arg_mount_settings | MOUNT_IN_USERNS,
+ arg_uid_shift,
+ arg_selinux_apifs_context);
+ if (r < 0)
+ return r;
+
+ if (!arg_network_namespace_path && arg_private_network) {
+ r = unshare(CLONE_NEWNET);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to unshare network namespace: %m");
+
+ /* Tell the parent that it can setup network interfaces. */
+ (void) barrier_place(barrier); /* #3 */
+ }
+
+ r = mount_sysfs(NULL, arg_mount_settings);
+ if (r < 0)
+ return r;
+
+ /* Wait until we are cgroup-ified, so that we
+ * can mount the right cgroup path writable */
+ if (!barrier_place_and_sync(barrier)) /* #4 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH),
+ "Parent died too early");
+
+ if (arg_use_cgns) {
+ r = unshare(CLONE_NEWCGROUP);
+ if (r < 0)
+ return log_error_errno(errno, "Failed to unshare cgroup namespace: %m");
+ r = mount_cgroups(
+ "",
+ arg_unified_cgroup_hierarchy,
+ arg_userns_mode != USER_NAMESPACE_NO,
+ arg_uid_shift,
+ arg_uid_range,
+ arg_selinux_apifs_context,
+ true);
+ } else
+ r = mount_systemd_cgroup_writable("", arg_unified_cgroup_hierarchy);
+ if (r < 0)
+ return r;
+
+ r = setup_boot_id();
+ if (r < 0)
+ return r;
+
+ r = setup_kmsg(fd_inner_socket);
+ if (r < 0)
+ return r;
+
+ r = mount_custom(
+ "/",
+ arg_custom_mounts,
+ arg_n_custom_mounts,
+ 0,
+ 0,
+ arg_selinux_apifs_context,
+ MOUNT_NON_ROOT_ONLY | MOUNT_IN_USERNS);
+ if (r < 0)
+ return r;
+
+ if (setsid() < 0)
+ return log_error_errno(errno, "setsid() failed: %m");
+
+ if (arg_private_network)
+ (void) loopback_setup();
+
+ if (arg_expose_ports) {
+ r = expose_port_send_rtnl(fd_inner_socket);
+ if (r < 0)
+ return r;
+ }
+
+ if (arg_console_mode != CONSOLE_PIPE) {
+ _cleanup_close_ int master = -EBADF;
+ _cleanup_free_ char *console = NULL;
+
+ /* Allocate a pty and make it available as /dev/console. */
+ master = openpt_allocate(O_RDWR|O_NONBLOCK, &console);
+ if (master < 0)
+ return log_error_errno(master, "Failed to allocate a pty: %m");
+
+ r = setup_dev_console(console);
+ if (r < 0)
+ return log_error_errno(r, "Failed to set up /dev/console: %m");
+
+ r = send_one_fd(fd_inner_socket, master, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to send master fd: %m");
+
+ r = setup_stdio_as_dev_console();
+ if (r < 0)
+ return r;
+ }
+
+ r = patch_sysctl();
+ if (r < 0)
+ return r;
+
+ if (arg_oom_score_adjust_set) {
+ r = set_oom_score_adjust(arg_oom_score_adjust);
+ if (r < 0)
+ return log_error_errno(r, "Failed to adjust OOM score: %m");
+ }
+
+ if (arg_cpu_set.set)
+ if (sched_setaffinity(0, arg_cpu_set.allocated, arg_cpu_set.set) < 0)
+ return log_error_errno(errno, "Failed to set CPU affinity: %m");
+
+ (void) setup_hostname();
+
+ if (arg_personality != PERSONALITY_INVALID) {
+ r = safe_personality(arg_personality);
+ if (r < 0)
+ return log_error_errno(r, "personality() failed: %m");
+#ifdef ARCHITECTURE_SECONDARY
+ } else if (arg_architecture == ARCHITECTURE_SECONDARY) {
+ r = safe_personality(PER_LINUX32);
+ if (r < 0)
+ return log_error_errno(r, "personality() failed: %m");
+#endif
+ } else if (!arg_quiet && arg_architecture >= 0 && arg_architecture != native_architecture())
+ log_notice("Selected architecture '%s' not supported natively on the local CPU, assuming "
+ "invocation with qemu userspace emulator (or equivalent) in effect.",
+ architecture_to_string(arg_architecture));
+
+ r = setrlimit_closest_all((const struct rlimit *const*) arg_rlimit, &which_failed);
+ if (r < 0)
+ return log_error_errno(r, "Failed to apply resource limit RLIMIT_%s: %m", rlimit_to_string(which_failed));
+
+#if HAVE_SECCOMP
+ if (arg_seccomp) {
+
+ if (is_seccomp_available()) {
+ r = seccomp_load(arg_seccomp);
+ if (ERRNO_IS_NEG_SECCOMP_FATAL(r))
+ return log_error_errno(r, "Failed to install seccomp filter: %m");
+ if (r < 0)
+ log_debug_errno(r, "Failed to install seccomp filter: %m");
+ }
+ } else
+#endif
+ {
+ r = setup_seccomp(arg_caps_retain, arg_syscall_allow_list, arg_syscall_deny_list);
+ if (r < 0)
+ return r;
+ }
+
+ if (arg_suppress_sync) {
+#if HAVE_SECCOMP
+ r = seccomp_suppress_sync();
+ if (r < 0)
+ log_debug_errno(r, "Failed to install sync() suppression seccomp filter, ignoring: %m");
+#else
+ log_debug("systemd is built without SECCOMP support. Ignoring --suppress-sync= command line option and SuppressSync= setting.");
+#endif
+ }
+
+#if HAVE_SELINUX
+ if (arg_selinux_context)
+ if (setexeccon(arg_selinux_context) < 0)
+ return log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context);
+#endif
+
+ /* Make sure we keep the caps across the uid/gid dropping, so that we can retain some selected caps
+ * if we need to later on. */
+ if (prctl(PR_SET_KEEPCAPS, 1) < 0)
+ return log_error_errno(errno, "Failed to set PR_SET_KEEPCAPS: %m");
+
+ if (uid_is_valid(arg_uid) || gid_is_valid(arg_gid))
+ r = change_uid_gid_raw(arg_uid, arg_gid, arg_supplementary_gids, arg_n_supplementary_gids, arg_console_mode != CONSOLE_PIPE);
+ else
+ r = change_uid_gid(arg_user, arg_console_mode != CONSOLE_PIPE, &home);
+ if (r < 0)
+ return r;
+
+ r = drop_capabilities(getuid());
+ if (r < 0)
+ return log_error_errno(r, "Dropping capabilities failed: %m");
+
+ if (arg_no_new_privileges)
+ if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0)
+ return log_error_errno(errno, "Failed to disable new privileges: %m");
+
+ /* LXC sets container=lxc, so follow the scheme here */
+ envp[n_env++] = strjoina("container=", arg_container_service_name);
+
+ envp[n_env] = strv_find_prefix(environ, "TERM=");
+ if (envp[n_env])
+ n_env++;
+
+ if (home || !uid_is_valid(arg_uid) || arg_uid == 0)
+ if (asprintf(envp + n_env++, "HOME=%s", home ?: "/root") < 0)
+ return log_oom();
+
+ if (arg_user || !uid_is_valid(arg_uid) || arg_uid == 0)
+ if (asprintf(envp + n_env++, "USER=%s", arg_user ?: "root") < 0 ||
+ asprintf(envp + n_env++, "LOGNAME=%s", arg_user ?: "root") < 0)
+ return log_oom();
+
+ assert(!sd_id128_is_null(arg_uuid));
+
+ if (asprintf(envp + n_env++, "container_uuid=%s", SD_ID128_TO_UUID_STRING(arg_uuid)) < 0)
+ return log_oom();
+
+ if (fdset_size(fds) > 0) {
+ r = fdset_cloexec(fds, false);
+ if (r < 0)
+ return log_error_errno(r, "Failed to unset O_CLOEXEC for file descriptors.");
+
+ if ((asprintf(envp + n_env++, "LISTEN_FDS=%u", fdset_size(fds)) < 0) ||
+ (asprintf(envp + n_env++, "LISTEN_PID=1") < 0))
+ return log_oom();
+ }
+ if (asprintf(envp + n_env++, "NOTIFY_SOCKET=%s", NSPAWN_NOTIFY_SOCKET_PATH) < 0)
+ return log_oom();
+
+ if (arg_n_credentials > 0) {
+ envp[n_env] = strdup("CREDENTIALS_DIRECTORY=/run/host/credentials");
+ if (!envp[n_env])
+ return log_oom();
+ n_env++;
+ }
+
+ if (arg_start_mode != START_BOOT) {
+ envp[n_env] = strdup("LANG=" SYSTEMD_NSPAWN_LOCALE);
+ if (!envp[n_env])
+ return log_oom();
+ n_env++;
+ }
+
+ env_use = strv_env_merge(envp, os_release_pairs, arg_setenv);
+ if (!env_use)
+ return log_oom();
+
+ /* Let the parent know that we are ready and wait until the parent is ready with the setup, too... */
+ if (!barrier_place_and_sync(barrier)) /* #5 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Parent died too early");
+
+ if (arg_chdir)
+ if (chdir(arg_chdir) < 0)
+ return log_error_errno(errno, "Failed to change to specified working directory %s: %m", arg_chdir);
+
+ if (arg_start_mode == START_PID2) {
+ r = stub_pid1(arg_uuid);
+ if (r < 0)
+ return r;
+ }
+
+ if (arg_console_mode != CONSOLE_PIPE) {
+ /* So far our pty wasn't controlled by any process. Finally, it's time to change that, if we
+ * are configured for that. Acquire it as controlling tty. */
+ if (ioctl(STDIN_FILENO, TIOCSCTTY) < 0)
+ return log_error_errno(errno, "Failed to acquire controlling TTY: %m");
+ }
+
+ log_debug("Inner child completed, invoking payload.");
+
+ /* Now, explicitly close the log, so that we then can close all remaining fds. Closing the log explicitly first
+ * has the benefit that the logging subsystem knows about it, and is thus ready to be reopened should we need
+ * it again. Note that the other fds closed here are at least the locking and barrier fds. */
+ log_close();
+ log_set_open_when_needed(true);
+ log_settle_target();
+
+ (void) fdset_close_others(fds);
+
+ if (arg_start_mode == START_BOOT) {
+ char **a;
+ size_t m;
+
+ /* Automatically search for the init system */
+
+ m = strv_length(arg_parameters);
+ a = newa(char*, m + 2);
+ memcpy_safe(a + 1, arg_parameters, m * sizeof(char*));
+ a[1 + m] = NULL;
+
+ FOREACH_STRING(init,
+ "/usr/lib/systemd/systemd",
+ "/lib/systemd/systemd",
+ "/sbin/init") {
+ a[0] = (char*) init;
+ execve(a[0], a, env_use);
+ }
+
+ exec_target = "/usr/lib/systemd/systemd, /lib/systemd/systemd, /sbin/init";
+ } else if (!strv_isempty(arg_parameters)) {
+ const char *dollar_path;
+
+ exec_target = arg_parameters[0];
+
+ /* Use the user supplied search $PATH if there is one, or DEFAULT_PATH_COMPAT if not to search the
+ * binary. */
+ dollar_path = strv_env_get(env_use, "PATH");
+ if (dollar_path) {
+ if (setenv("PATH", dollar_path, 1) < 0)
+ return log_error_errno(errno, "Failed to update $PATH: %m");
+ }
+
+ execvpe(arg_parameters[0], arg_parameters, env_use);
+ } else {
+ if (!arg_chdir)
+ /* If we cannot change the directory, we'll end up in /, that is expected. */
+ (void) chdir(home ?: "/root");
+
+ execle(DEFAULT_USER_SHELL, "-" DEFAULT_USER_SHELL_NAME, NULL, env_use);
+ if (!streq(DEFAULT_USER_SHELL, "/bin/bash"))
+ execle("/bin/bash", "-bash", NULL, env_use);
+ if (!streq(DEFAULT_USER_SHELL, "/bin/sh"))
+ execle("/bin/sh", "-sh", NULL, env_use);
+
+ exec_target = DEFAULT_USER_SHELL ", /bin/bash, /bin/sh";
+ }
+
+ return log_error_errno(errno, "execv(%s) failed: %m", exec_target);
+}
+
+static int setup_notify_child(void) {
+ _cleanup_close_ int fd = -EBADF;
+ static const union sockaddr_union sa = {
+ .un.sun_family = AF_UNIX,
+ .un.sun_path = NSPAWN_NOTIFY_SOCKET_PATH,
+ };
+ int r;
+
+ fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ if (fd < 0)
+ return log_error_errno(errno, "Failed to allocate notification socket: %m");
+
+ (void) mkdir_parents(NSPAWN_NOTIFY_SOCKET_PATH, 0755);
+ (void) sockaddr_un_unlink(&sa.un);
+
+ r = bind(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un));
+ if (r < 0)
+ return log_error_errno(errno, "bind(" NSPAWN_NOTIFY_SOCKET_PATH ") failed: %m");
+
+ r = userns_lchown(NSPAWN_NOTIFY_SOCKET_PATH, 0, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to chown " NSPAWN_NOTIFY_SOCKET_PATH ": %m");
+
+ r = setsockopt_int(fd, SOL_SOCKET, SO_PASSCRED, true);
+ if (r < 0)
+ return log_error_errno(r, "SO_PASSCRED failed: %m");
+
+ return TAKE_FD(fd);
+}
+
+static int outer_child(
+ Barrier *barrier,
+ const char *directory,
+ DissectedImage *dissected_image,
+ int fd_outer_socket,
+ int fd_inner_socket,
+ FDSet *fds,
+ int netns_fd) {
+
+ _cleanup_(bind_user_context_freep) BindUserContext *bind_user_context = NULL;
+ _cleanup_strv_free_ char **os_release_pairs = NULL;
+ _cleanup_close_ int fd = -EBADF, mntns_fd = -EBADF;
+ bool idmap = false;
+ const char *p;
+ pid_t pid;
+ ssize_t l;
+ int r;
+
+ /* This is the "outer" child process, i.e the one forked off by the container manager itself. It
+ * already has its own CLONE_NEWNS namespace (which was created by the clone()). It still lives in
+ * the host's CLONE_NEWPID, CLONE_NEWUTS, CLONE_NEWIPC, CLONE_NEWUSER and CLONE_NEWNET
+ * namespaces. After it completed a number of initializations a second child (the "inner" one) is
+ * forked off it, and it exits. */
+
+ assert(barrier);
+ assert(directory);
+ assert(fd_outer_socket >= 0);
+ assert(fd_inner_socket >= 0);
+
+ log_debug("Outer child is initializing.");
+
+ r = load_os_release_pairs_with_prefix("/", "container_host_", &os_release_pairs);
+ if (r < 0)
+ log_debug_errno(r, "Failed to read os-release from host for container, ignoring: %m");
+
+ if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0)
+ return log_error_errno(errno, "PR_SET_PDEATHSIG failed: %m");
+
+ r = reset_audit_loginuid();
+ if (r < 0)
+ return r;
+
+ /* Mark everything as slave, so that we still receive mounts from the real root, but don't propagate
+ * mounts to the real root. */
+ r = mount_follow_verbose(LOG_ERR, NULL, "/", NULL, MS_SLAVE|MS_REC, NULL);
+ if (r < 0)
+ return r;
+
+ if (dissected_image) {
+ /* If we are operating on a disk image, then mount its root directory now, but leave out the
+ * rest. We can read the UID shift from it if we need to. Further down we'll mount the rest,
+ * but then with the uid shift known. That way we can mount VFAT file systems shifted to the
+ * right place right away. This makes sure ESP partitions and userns are compatible. */
+
+ r = dissected_image_mount_and_warn(
+ dissected_image,
+ directory,
+ arg_uid_shift,
+ arg_uid_range,
+ /* userns_fd= */ -EBADF,
+ DISSECT_IMAGE_MOUNT_ROOT_ONLY|
+ DISSECT_IMAGE_DISCARD_ON_LOOP|
+ DISSECT_IMAGE_USR_NO_ROOT|
+ (arg_read_only ? DISSECT_IMAGE_READ_ONLY : DISSECT_IMAGE_FSCK|DISSECT_IMAGE_GROWFS)|
+ (arg_start_mode == START_BOOT ? DISSECT_IMAGE_VALIDATE_OS : 0));
+ if (r < 0)
+ return r;
+ }
+
+ r = determine_uid_shift(directory);
+ if (r < 0)
+ return r;
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ r = namespace_open(0, NULL, &mntns_fd, NULL, NULL, NULL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to pin outer mount namespace: %m");
+
+ l = send_one_fd(fd_outer_socket, mntns_fd, 0);
+ if (l < 0)
+ return log_error_errno(l, "Failed to send outer mount namespace fd: %m");
+ mntns_fd = safe_close(mntns_fd);
+
+ /* Let the parent know which UID shift we read from the image */
+ l = send(fd_outer_socket, &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))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short write while sending UID shift.");
+
+ if (arg_userns_mode == USER_NAMESPACE_PICK) {
+ /* When we are supposed to pick the UID shift, the parent will check now whether the
+ * UID shift we just read from the image is available. If yes, it will send the UID
+ * shift back to us, if not it will pick a different one, and send it back to us. */
+
+ l = recv(fd_outer_socket, &arg_uid_shift, sizeof(arg_uid_shift), 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to recv UID shift: %m");
+ if (l != sizeof(arg_uid_shift))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short read while receiving UID shift.");
+ }
+
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO,
+ "Selected user namespace base " UID_FMT " and range " UID_FMT ".", arg_uid_shift, arg_uid_range);
+ }
+
+ if (path_equal(directory, "/")) {
+ /* If the directory we shall boot is the host, let's operate on a bind mount at a different
+ * place, so that we can make changes to its mount structure (for example, to implement
+ * --volatile=) without this interfering with our ability to access files such as
+ * /etc/localtime to copy into the container. Note that we use a fixed place for this
+ * (instead of a temporary directory, since we are living in our own mount namespace here
+ * already, and thus don't need to be afraid of colliding with anyone else's mounts). */
+ (void) mkdir_p("/run/systemd/nspawn-root", 0755);
+
+ r = mount_nofollow_verbose(LOG_ERR, "/", "/run/systemd/nspawn-root", NULL, MS_BIND|MS_REC, NULL);
+ if (r < 0)
+ return r;
+
+ directory = "/run/systemd/nspawn-root";
+ }
+
+ /* Make sure we always have a mount that we can move to root later on. */
+ r = make_mount_point(directory);
+ if (r < 0)
+ return r;
+
+ /* So the whole tree is now MS_SLAVE, i.e. we'll still receive mount/umount events from the host
+ * mount namespace. For the directory we are going to run our container let's turn this off, so that
+ * we'll live in our own little world from now on, and propagation from the host may only happen via
+ * the mount tunnel dir, or not at all. */
+ r = mount_follow_verbose(LOG_ERR, NULL, directory, NULL, MS_PRIVATE|MS_REC, NULL);
+ if (r < 0)
+ return r;
+
+ r = setup_pivot_root(
+ directory,
+ arg_pivot_root_new,
+ arg_pivot_root_old);
+ if (r < 0)
+ return r;
+
+ r = setup_volatile_mode(
+ directory,
+ arg_volatile_mode,
+ arg_uid_shift,
+ arg_selinux_apifs_context);
+ if (r < 0)
+ return r;
+
+ r = bind_user_prepare(
+ directory,
+ arg_bind_user,
+ arg_uid_shift,
+ arg_uid_range,
+ &arg_custom_mounts, &arg_n_custom_mounts,
+ &bind_user_context);
+ if (r < 0)
+ return r;
+
+ if (arg_userns_mode != USER_NAMESPACE_NO && bind_user_context) {
+ /* Send the user maps we determined to the parent, so that it installs it in our user
+ * namespace UID map table */
+
+ for (size_t i = 0; i < bind_user_context->n_data; i++) {
+ uid_t map[] = {
+ bind_user_context->data[i].payload_user->uid,
+ bind_user_context->data[i].host_user->uid,
+ (uid_t) bind_user_context->data[i].payload_group->gid,
+ (uid_t) bind_user_context->data[i].host_group->gid,
+ };
+
+ l = send(fd_outer_socket, map, sizeof(map), MSG_NOSIGNAL);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to send user UID map: %m");
+ if (l != sizeof(map))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short write while sending user UID map.");
+ }
+ }
+
+ r = mount_custom(
+ directory,
+ arg_custom_mounts,
+ arg_n_custom_mounts,
+ arg_uid_shift,
+ arg_uid_range,
+ arg_selinux_apifs_context,
+ MOUNT_ROOT_ONLY);
+ if (r < 0)
+ return r;
+
+ if (arg_userns_mode != USER_NAMESPACE_NO &&
+ IN_SET(arg_userns_ownership, USER_NAMESPACE_OWNERSHIP_MAP, USER_NAMESPACE_OWNERSHIP_AUTO) &&
+ arg_uid_shift != 0) {
+ _cleanup_free_ char *usr_subtree = NULL;
+ char *dirs[3];
+ size_t i = 0;
+
+ dirs[i++] = (char*) directory;
+
+ if (dissected_image && dissected_image->partitions[PARTITION_USR].found) {
+ usr_subtree = path_join(directory, "/usr");
+ if (!usr_subtree)
+ return log_oom();
+
+ dirs[i++] = usr_subtree;
+ }
+
+ dirs[i] = NULL;
+
+ r = remount_idmap(dirs, arg_uid_shift, arg_uid_range, UID_INVALID, REMOUNT_IDMAPPING_HOST_ROOT);
+ if (r == -EINVAL || ERRNO_IS_NEG_NOT_SUPPORTED(r)) {
+ /* This might fail because the kernel or file system doesn't support idmapping. We
+ * can't really distinguish this nicely, nor do we have any guarantees about the
+ * error codes we see, could be EOPNOTSUPP or EINVAL. */
+ if (arg_userns_ownership != USER_NAMESPACE_OWNERSHIP_AUTO)
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "ID mapped mounts are apparently not available, sorry.");
+
+ log_debug("ID mapped mounts are apparently not available on this kernel or for the selected file system, reverting to recursive chown()ing.");
+ arg_userns_ownership = USER_NAMESPACE_OWNERSHIP_CHOWN;
+ } else if (r < 0)
+ return log_error_errno(r, "Failed to set up ID mapped mounts: %m");
+ else {
+ log_debug("ID mapped mounts available, making use of them.");
+ idmap = true;
+ }
+ }
+
+ if (dissected_image) {
+ /* Now we know the uid shift, let's now mount everything else that might be in the image. */
+ r = dissected_image_mount(
+ dissected_image,
+ directory,
+ arg_uid_shift,
+ arg_uid_range,
+ /* userns_fd= */ -EBADF,
+ DISSECT_IMAGE_MOUNT_NON_ROOT_ONLY|
+ DISSECT_IMAGE_DISCARD_ON_LOOP|
+ DISSECT_IMAGE_USR_NO_ROOT|
+ (arg_read_only ? DISSECT_IMAGE_READ_ONLY : DISSECT_IMAGE_FSCK|DISSECT_IMAGE_GROWFS)|
+ (idmap ? DISSECT_IMAGE_MOUNT_IDMAPPED : 0));
+ if (r == -EUCLEAN)
+ return log_error_errno(r, "File system check for image failed: %m");
+ if (r < 0)
+ return log_error_errno(r, "Failed to mount image file system: %m");
+ }
+
+ if (arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN) {
+ /* OK, we don't know yet which cgroup mode to use yet. Let's figure it out, and tell the parent. */
+
+ r = detect_unified_cgroup_hierarchy_from_image(directory);
+ if (r < 0)
+ return r;
+
+ l = send(fd_outer_socket, &arg_unified_cgroup_hierarchy, sizeof(arg_unified_cgroup_hierarchy), MSG_NOSIGNAL);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to send cgroup mode: %m");
+ if (l != sizeof(arg_unified_cgroup_hierarchy))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short write while sending cgroup mode.");
+ }
+
+ r = recursive_chown(directory, arg_uid_shift, arg_uid_range);
+ if (r < 0)
+ return r;
+
+ r = base_filesystem_create(directory, arg_uid_shift, (gid_t) arg_uid_shift);
+ if (r < 0)
+ return r;
+
+ if (arg_read_only && arg_volatile_mode == VOLATILE_NO &&
+ !has_custom_root_mount(arg_custom_mounts, arg_n_custom_mounts)) {
+ r = bind_remount_recursive(directory, MS_RDONLY, MS_RDONLY, NULL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to make tree read-only: %m");
+ }
+
+ r = mount_all(directory,
+ arg_mount_settings,
+ arg_uid_shift,
+ arg_selinux_apifs_context);
+ if (r < 0)
+ return r;
+
+ r = copy_devnodes(directory);
+ if (r < 0)
+ return r;
+
+ r = make_extra_nodes(directory);
+ if (r < 0)
+ return r;
+
+ (void) dev_setup(directory, arg_uid_shift, arg_uid_shift);
+
+ p = prefix_roota(directory, "/run/host");
+ (void) make_inaccessible_nodes(p, arg_uid_shift, arg_uid_shift);
+
+ r = setup_pts(directory);
+ if (r < 0)
+ return r;
+
+ r = mount_tunnel_dig(directory);
+ if (r < 0)
+ return r;
+
+ r = setup_keyring();
+ if (r < 0)
+ return r;
+
+ r = setup_credentials(directory);
+ if (r < 0)
+ return r;
+
+ r = bind_user_setup(bind_user_context, directory);
+ if (r < 0)
+ return r;
+
+ r = mount_custom(
+ directory,
+ arg_custom_mounts,
+ arg_n_custom_mounts,
+ arg_uid_shift,
+ arg_uid_range,
+ arg_selinux_apifs_context,
+ MOUNT_NON_ROOT_ONLY);
+ if (r < 0)
+ return r;
+
+ r = setup_timezone(directory);
+ if (r < 0)
+ return r;
+
+ r = setup_resolv_conf(directory);
+ if (r < 0)
+ return r;
+
+ r = setup_machine_id(directory);
+ if (r < 0)
+ return r;
+
+ r = setup_journal(directory);
+ if (r < 0)
+ return r;
+
+ /* The same stuff as the $container env var, but nicely readable for the entire payload */
+ p = prefix_roota(directory, "/run/host/container-manager");
+ (void) write_string_file(p, arg_container_service_name, WRITE_STRING_FILE_CREATE);
+
+ /* The same stuff as the $container_uuid env var */
+ p = prefix_roota(directory, "/run/host/container-uuid");
+ (void) write_string_filef(p, WRITE_STRING_FILE_CREATE, SD_ID128_UUID_FORMAT_STR, SD_ID128_FORMAT_VAL(arg_uuid));
+
+ if (!arg_use_cgns) {
+ r = mount_cgroups(
+ directory,
+ arg_unified_cgroup_hierarchy,
+ arg_userns_mode != USER_NAMESPACE_NO,
+ arg_uid_shift,
+ arg_uid_range,
+ arg_selinux_apifs_context,
+ false);
+ if (r < 0)
+ return r;
+ }
+
+ /* Mark everything as shared so our mounts get propagated down. This is required to make new bind
+ * mounts available in systemd services inside the container that create a new mount namespace. See
+ * https://github.com/systemd/systemd/issues/3860 Further submounts (such as /dev) done after this
+ * will inherit the shared propagation mode.
+ *
+ * IMPORTANT: Do not overmount the root directory anymore from now on to enable moving the root
+ * directory mount to root later on.
+ * https://github.com/systemd/systemd/issues/3847#issuecomment-562735251
+ */
+ r = mount_switch_root(directory, MS_SHARED);
+ if (r < 0)
+ return log_error_errno(r, "Failed to move root directory: %m");
+
+ /* We finished setting up the rootfs which is a shared mount. The mount tunnel needs to be a
+ * dependent mount otherwise we can't MS_MOVE mounts that were propagated from the host into
+ * the container. */
+ r = mount_tunnel_open();
+ if (r < 0)
+ return r;
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ /* In order to mount procfs and sysfs in an unprivileged container the kernel
+ * requires that a fully visible instance is already present in the target mount
+ * namespace. Mount one here so the inner child can mount its own instances. Later
+ * we umount the temporary instances created here before we actually exec the
+ * payload. Since the rootfs is shared the umount will propagate into the container.
+ * Note, the inner child wouldn't be able to unmount the instances on its own since
+ * it doesn't own the originating mount namespace. IOW, the outer child needs to do
+ * this. */
+ r = pin_fully_visible_fs();
+ if (r < 0)
+ return r;
+ }
+
+ fd = setup_notify_child();
+ if (fd < 0)
+ return fd;
+
+ pid = raw_clone(SIGCHLD|CLONE_NEWNS|
+ arg_clone_ns_flags |
+ (arg_userns_mode != USER_NAMESPACE_NO ? CLONE_NEWUSER : 0));
+ if (pid < 0)
+ return log_error_errno(errno, "Failed to fork inner child: %m");
+ if (pid == 0) {
+ fd_outer_socket = safe_close(fd_outer_socket);
+
+ /* The inner child has all namespaces that are requested, so that we all are owned by the
+ * user if user namespaces are turned on. */
+
+ if (arg_network_namespace_path) {
+ r = namespace_enter(-1, -1, netns_fd, -1, -1);
+ if (r < 0)
+ return log_error_errno(r, "Failed to join network namespace: %m");
+ }
+
+ r = inner_child(barrier, fd_inner_socket, fds, os_release_pairs);
+ if (r < 0)
+ _exit(EXIT_FAILURE);
+
+ _exit(EXIT_SUCCESS);
+ }
+
+ l = send(fd_outer_socket, &pid, sizeof(pid), MSG_NOSIGNAL);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to send PID: %m");
+ if (l != sizeof(pid))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short write while sending PID.");
+
+ l = send(fd_outer_socket, &arg_uuid, sizeof(arg_uuid), MSG_NOSIGNAL);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to send machine ID: %m");
+ if (l != sizeof(arg_uuid))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO),
+ "Short write while sending machine ID.");
+
+ l = send_one_fd(fd_outer_socket, fd, 0);
+ if (l < 0)
+ return log_error_errno(l, "Failed to send notify fd: %m");
+
+ fd_outer_socket = safe_close(fd_outer_socket);
+ fd_inner_socket = safe_close(fd_inner_socket);
+ netns_fd = safe_close(netns_fd);
+
+ return 0;
+}
+
+static int uid_shift_pick(uid_t *shift, LockFile *ret_lock_file) {
+ bool tried_hashed = false;
+ unsigned n_tries = 100;
+ uid_t candidate;
+ int r;
+
+ assert(shift);
+ assert(ret_lock_file);
+ assert(arg_userns_mode == USER_NAMESPACE_PICK);
+ assert(arg_uid_range == 0x10000U);
+
+ candidate = *shift;
+
+ (void) mkdir("/run/systemd/nspawn-uid", 0755);
+
+ for (;;) {
+ char lock_path[STRLEN("/run/systemd/nspawn-uid/") + DECIMAL_STR_MAX(uid_t) + 1];
+ _cleanup_(release_lock_file) LockFile lf = LOCK_FILE_INIT;
+
+ if (--n_tries <= 0)
+ return -EBUSY;
+
+ if (candidate < CONTAINER_UID_BASE_MIN || candidate > CONTAINER_UID_BASE_MAX)
+ goto next;
+ if ((candidate & UINT32_C(0xFFFF)) != 0)
+ goto next;
+
+ xsprintf(lock_path, "/run/systemd/nspawn-uid/" UID_FMT, candidate);
+ r = make_lock_file(lock_path, LOCK_EX|LOCK_NB, &lf);
+ if (r == -EBUSY) /* Range already taken by another nspawn instance */
+ goto next;
+ if (r < 0)
+ return r;
+
+ /* Make some superficial checks whether the range is currently known in the user database */
+ if (getpwuid(candidate))
+ goto next;
+ if (getpwuid(candidate + UINT32_C(0xFFFE)))
+ goto next;
+ if (getgrgid(candidate))
+ goto next;
+ if (getgrgid(candidate + UINT32_C(0xFFFE)))
+ goto next;
+
+ *ret_lock_file = lf;
+ lf = (struct LockFile) LOCK_FILE_INIT;
+ *shift = candidate;
+ return 0;
+
+ next:
+ if (arg_machine && !tried_hashed) {
+ /* Try to hash the base from the container name */
+
+ static const uint8_t hash_key[] = {
+ 0xe1, 0x56, 0xe0, 0xf0, 0x4a, 0xf0, 0x41, 0xaf,
+ 0x96, 0x41, 0xcf, 0x41, 0x33, 0x94, 0xff, 0x72
+ };
+
+ candidate = (uid_t) siphash24(arg_machine, strlen(arg_machine), hash_key);
+
+ tried_hashed = true;
+ } else
+ random_bytes(&candidate, sizeof(candidate));
+
+ candidate = (candidate % (CONTAINER_UID_BASE_MAX - CONTAINER_UID_BASE_MIN)) + CONTAINER_UID_BASE_MIN;
+ candidate &= (uid_t) UINT32_C(0xFFFF0000);
+ }
+}
+
+static int add_one_uid_map(
+ char **p,
+ uid_t container_uid,
+ uid_t host_uid,
+ uid_t range) {
+
+ return strextendf(p,
+ UID_FMT " " UID_FMT " " UID_FMT "\n",
+ container_uid, host_uid, range);
+}
+
+static int make_uid_map_string(
+ const uid_t bind_user_uid[],
+ size_t n_bind_user_uid,
+ size_t offset,
+ char **ret) {
+
+ _cleanup_free_ char *s = NULL;
+ uid_t previous_uid = 0;
+ int r;
+
+ assert(n_bind_user_uid == 0 || bind_user_uid);
+ assert(IN_SET(offset, 0, 2)); /* used to switch between UID and GID map */
+ assert(ret);
+
+ /* The bind_user_uid[] array is a series of 4 uid_t values, for each --bind-user= entry one
+ * quadruplet, consisting of host and container UID + GID. */
+
+ for (size_t i = 0; i < n_bind_user_uid; i++) {
+ uid_t payload_uid = bind_user_uid[i*4+offset],
+ host_uid = bind_user_uid[i*4+offset+1];
+
+ assert(previous_uid <= payload_uid);
+ assert(payload_uid < arg_uid_range);
+
+ /* Add a range to close the gap to previous entry */
+ if (payload_uid > previous_uid) {
+ r = add_one_uid_map(&s, previous_uid, arg_uid_shift + previous_uid, payload_uid - previous_uid);
+ if (r < 0)
+ return r;
+ }
+
+ /* Map this specific user */
+ r = add_one_uid_map(&s, payload_uid, host_uid, 1);
+ if (r < 0)
+ return r;
+
+ previous_uid = payload_uid + 1;
+ }
+
+ /* And add a range to close the gap to finish the range */
+ if (arg_uid_range > previous_uid) {
+ r = add_one_uid_map(&s, previous_uid, arg_uid_shift + previous_uid, arg_uid_range - previous_uid);
+ if (r < 0)
+ return r;
+ }
+
+ assert(s);
+
+ *ret = TAKE_PTR(s);
+ return 0;
+}
+
+static int setup_uid_map(
+ pid_t pid,
+ const uid_t bind_user_uid[],
+ size_t n_bind_user_uid) {
+
+ char uid_map[STRLEN("/proc//uid_map") + DECIMAL_STR_MAX(uid_t) + 1];
+ _cleanup_free_ char *s = NULL;
+ int r;
+
+ assert(pid > 1);
+
+ /* Build the UID map string */
+ if (make_uid_map_string(bind_user_uid, n_bind_user_uid, 0, &s) < 0) /* offset=0 contains the UID pair */
+ return log_oom();
+
+ xsprintf(uid_map, "/proc/" PID_FMT "/uid_map", pid);
+ r = write_string_file(uid_map, s, WRITE_STRING_FILE_DISABLE_BUFFER);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write UID map: %m");
+
+ /* And now build the GID map string */
+ s = mfree(s);
+ if (make_uid_map_string(bind_user_uid, n_bind_user_uid, 2, &s) < 0) /* offset=2 contains the GID pair */
+ return log_oom();
+
+ xsprintf(uid_map, "/proc/" PID_FMT "/gid_map", pid);
+ r = write_string_file(uid_map, s, WRITE_STRING_FILE_DISABLE_BUFFER);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write GID map: %m");
+
+ return 0;
+}
+
+static int nspawn_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t revents, void *userdata) {
+ char buf[NOTIFY_BUFFER_MAX+1];
+ char *p = NULL;
+ struct iovec iovec = {
+ .iov_base = buf,
+ .iov_len = sizeof(buf)-1,
+ };
+ CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct ucred)) +
+ CMSG_SPACE(sizeof(int) * NOTIFY_FD_MAX)) control;
+ struct msghdr msghdr = {
+ .msg_iov = &iovec,
+ .msg_iovlen = 1,
+ .msg_control = &control,
+ .msg_controllen = sizeof(control),
+ };
+ struct ucred *ucred;
+ ssize_t n;
+ pid_t inner_child_pid;
+ _cleanup_strv_free_ char **tags = NULL;
+ int r;
+
+ assert(userdata);
+
+ inner_child_pid = PTR_TO_PID(userdata);
+
+ if (revents != EPOLLIN) {
+ log_warning("Got unexpected poll event for notify fd.");
+ return 0;
+ }
+
+ n = recvmsg_safe(fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
+ if (ERRNO_IS_NEG_TRANSIENT(n))
+ return 0;
+ else if (n == -EXFULL) {
+ log_warning("Got message with truncated control data (too many fds sent?), ignoring.");
+ return 0;
+ } else if (n < 0)
+ return log_warning_errno(n, "Couldn't read notification socket: %m");
+
+ cmsg_close_all(&msghdr);
+
+ ucred = CMSG_FIND_DATA(&msghdr, SOL_SOCKET, SCM_CREDENTIALS, struct ucred);
+ if (!ucred || ucred->pid != inner_child_pid) {
+ log_debug("Received notify message without valid credentials. Ignoring.");
+ return 0;
+ }
+
+ if ((size_t) n >= sizeof(buf)) {
+ log_warning("Received notify message exceeded maximum size. Ignoring.");
+ return 0;
+ }
+
+ buf[n] = 0;
+ tags = strv_split(buf, "\n\r");
+ if (!tags)
+ return log_oom();
+
+ if (strv_contains(tags, "READY=1")) {
+ r = sd_notify(false, "READY=1\n");
+ if (r < 0)
+ log_warning_errno(r, "Failed to send readiness notification, ignoring: %m");
+ }
+
+ p = strv_find_startswith(tags, "STATUS=");
+ if (p)
+ (void) sd_notifyf(false, "STATUS=Container running: %s", p);
+
+ return 0;
+}
+
+static int setup_notify_parent(sd_event *event, int fd, pid_t *inner_child_pid, sd_event_source **notify_event_source) {
+ int r;
+
+ r = sd_event_add_io(event, notify_event_source, fd, EPOLLIN, nspawn_dispatch_notify_fd, inner_child_pid);
+ if (r < 0)
+ return log_error_errno(r, "Failed to allocate notify event source: %m");
+
+ (void) sd_event_source_set_description(*notify_event_source, "nspawn-notify");
+
+ return 0;
+}
+
+static int merge_settings(Settings *settings, const char *path) {
+ int rl;
+
+ assert(settings);
+ assert(path);
+
+ /* Copy over bits from the settings, unless they have been explicitly masked by command line switches. Note
+ * that this steals the fields of the Settings* structure, and hence modifies it. */
+
+ if ((arg_settings_mask & SETTING_START_MODE) == 0 &&
+ settings->start_mode >= 0) {
+ arg_start_mode = settings->start_mode;
+ strv_free_and_replace(arg_parameters, settings->parameters);
+ }
+
+ if ((arg_settings_mask & SETTING_EPHEMERAL) == 0 &&
+ settings->ephemeral >= 0)
+ arg_ephemeral = settings->ephemeral;
+
+ if ((arg_settings_mask & SETTING_DIRECTORY) == 0 &&
+ settings->root) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring root directory setting, file %s is not trusted.", path);
+ else
+ free_and_replace(arg_directory, settings->root);
+ }
+
+ if ((arg_settings_mask & SETTING_PIVOT_ROOT) == 0 &&
+ settings->pivot_root_new) {
+ free_and_replace(arg_pivot_root_new, settings->pivot_root_new);
+ free_and_replace(arg_pivot_root_old, settings->pivot_root_old);
+ }
+
+ if ((arg_settings_mask & SETTING_WORKING_DIRECTORY) == 0 &&
+ settings->working_directory)
+ free_and_replace(arg_chdir, settings->working_directory);
+
+ if ((arg_settings_mask & SETTING_ENVIRONMENT) == 0 &&
+ settings->environment)
+ strv_free_and_replace(arg_setenv, settings->environment);
+
+ if ((arg_settings_mask & SETTING_USER) == 0) {
+
+ if (settings->user)
+ free_and_replace(arg_user, settings->user);
+
+ if (uid_is_valid(settings->uid))
+ arg_uid = settings->uid;
+ if (gid_is_valid(settings->gid))
+ arg_gid = settings->gid;
+ if (settings->n_supplementary_gids > 0) {
+ free_and_replace(arg_supplementary_gids, settings->supplementary_gids);
+ arg_n_supplementary_gids = settings->n_supplementary_gids;
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_CAPABILITY) == 0) {
+ uint64_t plus, minus;
+ uint64_t network_minus = 0;
+ uint64_t ambient;
+
+ /* Note that we copy both the simple plus/minus caps here, and the full quintet from the
+ * Settings structure */
+
+ plus = settings->capability;
+ minus = settings->drop_capability;
+
+ if ((arg_settings_mask & SETTING_NETWORK) == 0 &&
+ settings_network_configured(settings)) {
+ if (settings_private_network(settings))
+ plus |= UINT64_C(1) << CAP_NET_ADMIN;
+ else
+ network_minus |= UINT64_C(1) << CAP_NET_ADMIN;
+ }
+
+ if (!arg_settings_trusted && plus != 0) {
+ if (settings->capability != 0)
+ log_warning("Ignoring Capability= setting, file %s is not trusted.", path);
+ } else {
+ arg_caps_retain &= ~network_minus;
+ arg_caps_retain |= plus;
+ }
+
+ arg_caps_retain &= ~minus;
+
+ /* Copy the full capabilities over too */
+ if (capability_quintet_is_set(&settings->full_capabilities)) {
+ if (!arg_settings_trusted)
+ log_warning("Ignoring capability settings, file %s is not trusted.", path);
+ else
+ arg_full_capabilities = settings->full_capabilities;
+ }
+
+ ambient = settings->ambient_capability;
+ if (!arg_settings_trusted && ambient != 0)
+ log_warning("Ignoring AmbientCapability= setting, file %s is not trusted.", path);
+ else
+ arg_caps_ambient |= ambient;
+ }
+
+ if ((arg_settings_mask & SETTING_KILL_SIGNAL) == 0 &&
+ settings->kill_signal > 0)
+ arg_kill_signal = settings->kill_signal;
+
+ if ((arg_settings_mask & SETTING_PERSONALITY) == 0 &&
+ settings->personality != PERSONALITY_INVALID)
+ arg_personality = settings->personality;
+
+ if ((arg_settings_mask & SETTING_MACHINE_ID) == 0 &&
+ !sd_id128_is_null(settings->machine_id)) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring MachineID= setting, file %s is not trusted.", path);
+ else
+ arg_uuid = settings->machine_id;
+ }
+
+ if ((arg_settings_mask & SETTING_READ_ONLY) == 0 &&
+ settings->read_only >= 0)
+ arg_read_only = settings->read_only;
+
+ if ((arg_settings_mask & SETTING_VOLATILE_MODE) == 0 &&
+ settings->volatile_mode != _VOLATILE_MODE_INVALID)
+ arg_volatile_mode = settings->volatile_mode;
+
+ if ((arg_settings_mask & SETTING_CUSTOM_MOUNTS) == 0 &&
+ settings->n_custom_mounts > 0) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring TemporaryFileSystem=, Bind= and BindReadOnly= settings, file %s is not trusted.", path);
+ else {
+ custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts);
+ arg_custom_mounts = TAKE_PTR(settings->custom_mounts);
+ arg_n_custom_mounts = settings->n_custom_mounts;
+ settings->n_custom_mounts = 0;
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_NETWORK) == 0 &&
+ settings_network_configured(settings)) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring network settings, file %s is not trusted.", path);
+ else {
+ arg_network_veth = settings_network_veth(settings);
+ arg_private_network = settings_private_network(settings);
+
+ strv_free_and_replace(arg_network_interfaces, settings->network_interfaces);
+ strv_free_and_replace(arg_network_macvlan, settings->network_macvlan);
+ strv_free_and_replace(arg_network_ipvlan, settings->network_ipvlan);
+ strv_free_and_replace(arg_network_veth_extra, settings->network_veth_extra);
+
+ free_and_replace(arg_network_bridge, settings->network_bridge);
+ free_and_replace(arg_network_zone, settings->network_zone);
+
+ free_and_replace(arg_network_namespace_path, settings->network_namespace_path);
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_EXPOSE_PORTS) == 0 &&
+ settings->expose_ports) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring Port= setting, file %s is not trusted.", path);
+ else {
+ expose_port_free_all(arg_expose_ports);
+ arg_expose_ports = TAKE_PTR(settings->expose_ports);
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_USERNS) == 0 &&
+ settings->userns_mode != _USER_NAMESPACE_MODE_INVALID) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring PrivateUsers= and PrivateUsersChown= settings, file %s is not trusted.", path);
+ else {
+ arg_userns_mode = settings->userns_mode;
+ arg_uid_shift = settings->uid_shift;
+ arg_uid_range = settings->uid_range;
+ arg_userns_ownership = settings->userns_ownership;
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_BIND_USER) == 0 &&
+ !strv_isempty(settings->bind_user))
+ strv_free_and_replace(arg_bind_user, settings->bind_user);
+
+ if ((arg_settings_mask & SETTING_NOTIFY_READY) == 0 &&
+ settings->notify_ready >= 0)
+ arg_notify_ready = settings->notify_ready;
+
+ if ((arg_settings_mask & SETTING_SYSCALL_FILTER) == 0) {
+
+ if (!strv_isempty(settings->syscall_allow_list) || !strv_isempty(settings->syscall_deny_list)) {
+ if (!arg_settings_trusted && !strv_isempty(settings->syscall_allow_list))
+ log_warning("Ignoring SystemCallFilter= settings, file %s is not trusted.", path);
+ else {
+ strv_free_and_replace(arg_syscall_allow_list, settings->syscall_allow_list);
+ strv_free_and_replace(arg_syscall_deny_list, settings->syscall_deny_list);
+ }
+ }
+
+#if HAVE_SECCOMP
+ if (settings->seccomp) {
+ if (!arg_settings_trusted)
+ log_warning("Ignoring SECCOMP filter, file %s is not trusted.", path);
+ else {
+ seccomp_release(arg_seccomp);
+ arg_seccomp = TAKE_PTR(settings->seccomp);
+ }
+ }
+#endif
+ }
+
+ for (rl = 0; rl < _RLIMIT_MAX; rl ++) {
+ if ((arg_settings_mask & (SETTING_RLIMIT_FIRST << rl)))
+ continue;
+
+ if (!settings->rlimit[rl])
+ continue;
+
+ if (!arg_settings_trusted) {
+ log_warning("Ignoring Limit%s= setting, file '%s' is not trusted.", rlimit_to_string(rl), path);
+ continue;
+ }
+
+ free_and_replace(arg_rlimit[rl], settings->rlimit[rl]);
+ }
+
+ if ((arg_settings_mask & SETTING_HOSTNAME) == 0 &&
+ settings->hostname)
+ free_and_replace(arg_hostname, settings->hostname);
+
+ if ((arg_settings_mask & SETTING_NO_NEW_PRIVILEGES) == 0 &&
+ settings->no_new_privileges >= 0)
+ arg_no_new_privileges = settings->no_new_privileges;
+
+ if ((arg_settings_mask & SETTING_OOM_SCORE_ADJUST) == 0 &&
+ settings->oom_score_adjust_set) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring OOMScoreAdjust= setting, file '%s' is not trusted.", path);
+ else {
+ arg_oom_score_adjust = settings->oom_score_adjust;
+ arg_oom_score_adjust_set = true;
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_CPU_AFFINITY) == 0 &&
+ settings->cpu_set.set) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring CPUAffinity= setting, file '%s' is not trusted.", path);
+ else {
+ cpu_set_reset(&arg_cpu_set);
+ arg_cpu_set = TAKE_STRUCT(settings->cpu_set);
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_RESOLV_CONF) == 0 &&
+ settings->resolv_conf != _RESOLV_CONF_MODE_INVALID)
+ arg_resolv_conf = settings->resolv_conf;
+
+ if ((arg_settings_mask & SETTING_LINK_JOURNAL) == 0 &&
+ settings->link_journal != _LINK_JOURNAL_INVALID) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring journal link setting, file '%s' is not trusted.", path);
+ else {
+ arg_link_journal = settings->link_journal;
+ arg_link_journal_try = settings->link_journal_try;
+ }
+ }
+
+ if ((arg_settings_mask & SETTING_TIMEZONE) == 0 &&
+ settings->timezone != _TIMEZONE_MODE_INVALID)
+ arg_timezone = settings->timezone;
+
+ if ((arg_settings_mask & SETTING_SLICE) == 0 &&
+ settings->slice) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring slice setting, file '%s' is not trusted.", path);
+ else
+ free_and_replace(arg_slice, settings->slice);
+ }
+
+ if ((arg_settings_mask & SETTING_USE_CGNS) == 0 &&
+ settings->use_cgns >= 0) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring cgroup namespace setting, file '%s' is not trusted.", path);
+ else
+ arg_use_cgns = settings->use_cgns;
+ }
+
+ if ((arg_settings_mask & SETTING_CLONE_NS_FLAGS) == 0 &&
+ settings->clone_ns_flags != ULONG_MAX) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring namespace setting, file '%s' is not trusted.", path);
+ else
+ arg_clone_ns_flags = settings->clone_ns_flags;
+ }
+
+ if ((arg_settings_mask & SETTING_CONSOLE_MODE) == 0 &&
+ settings->console_mode >= 0) {
+
+ if (!arg_settings_trusted)
+ log_warning("Ignoring console mode setting, file '%s' is not trusted.", path);
+ else
+ arg_console_mode = settings->console_mode;
+ }
+
+ if ((arg_settings_mask & SETTING_SUPPRESS_SYNC) == 0 &&
+ settings->suppress_sync >= 0)
+ arg_suppress_sync = settings->suppress_sync;
+
+ /* The following properties can only be set through the OCI settings logic, not from the command line, hence we
+ * don't consult arg_settings_mask for them. */
+
+ sd_bus_message_unref(arg_property_message);
+ arg_property_message = TAKE_PTR(settings->properties);
+
+ arg_console_width = settings->console_width;
+ arg_console_height = settings->console_height;
+
+ device_node_array_free(arg_extra_nodes, arg_n_extra_nodes);
+ arg_extra_nodes = TAKE_PTR(settings->extra_nodes);
+ arg_n_extra_nodes = settings->n_extra_nodes;
+ settings->n_extra_nodes = 0;
+
+ return 0;
+}
+
+static int load_settings(void) {
+ _cleanup_(settings_freep) Settings *settings = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ _cleanup_free_ char *p = NULL;
+ int r;
+
+ if (arg_oci_bundle)
+ return 0;
+
+ /* If all settings are masked, there's no point in looking for
+ * the settings file */
+ if (FLAGS_SET(arg_settings_mask, _SETTINGS_MASK_ALL))
+ return 0;
+
+ /* We first look in the admin's directories in /etc and /run */
+ FOREACH_STRING(i, "/etc/systemd/nspawn", "/run/systemd/nspawn") {
+ _cleanup_free_ char *j = NULL;
+
+ j = path_join(i, arg_settings_filename);
+ if (!j)
+ return log_oom();
+
+ f = fopen(j, "re");
+ if (f) {
+ p = TAKE_PTR(j);
+
+ /* By default, we trust configuration from /etc and /run */
+ if (arg_settings_trusted < 0)
+ arg_settings_trusted = true;
+
+ break;
+ }
+
+ if (errno != ENOENT)
+ return log_error_errno(errno, "Failed to open %s: %m", j);
+ }
+
+ if (!f) {
+ /* After that, let's look for a file next to the
+ * actual image we shall boot. */
+
+ if (arg_image) {
+ r = file_in_same_dir(arg_image, arg_settings_filename, &p);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate settings path from image path: %m");
+ } else if (arg_directory) {
+ r = file_in_same_dir(arg_directory, arg_settings_filename, &p);
+ if (r < 0 && r != -EADDRNOTAVAIL) /* if directory is root fs, don't complain */
+ return log_error_errno(r, "Failed to generate settings path from directory path: %m");
+ }
+
+ if (p) {
+ f = fopen(p, "re");
+ if (!f && errno != ENOENT)
+ return log_error_errno(errno, "Failed to open %s: %m", p);
+
+ /* By default, we do not trust configuration from /var/lib/machines */
+ if (arg_settings_trusted < 0)
+ arg_settings_trusted = false;
+ }
+ }
+
+ if (!f)
+ return 0;
+
+ log_debug("Settings are trusted: %s", yes_no(arg_settings_trusted));
+
+ r = settings_load(f, p, &settings);
+ if (r < 0)
+ return r;
+
+ return merge_settings(settings, p);
+}
+
+static int load_oci_bundle(void) {
+ _cleanup_(settings_freep) Settings *settings = NULL;
+ int r;
+
+ if (!arg_oci_bundle)
+ return 0;
+
+ /* By default let's trust OCI bundles */
+ if (arg_settings_trusted < 0)
+ arg_settings_trusted = true;
+
+ r = oci_load(NULL, arg_oci_bundle, &settings);
+ if (r < 0)
+ return r;
+
+ return merge_settings(settings, arg_oci_bundle);
+}
+
+static int run_container(
+ DissectedImage *dissected_image,
+ FDSet *fds,
+ char veth_name[IFNAMSIZ], bool *veth_created,
+ struct ExposeArgs *expose_args,
+ int *master, pid_t *pid, int *ret) {
+
+ static const struct sigaction sa = {
+ .sa_handler = nop_signal_handler,
+ .sa_flags = SA_NOCLDSTOP|SA_RESTART,
+ };
+
+ _cleanup_(release_lock_file) LockFile uid_shift_lock = LOCK_FILE_INIT;
+ _cleanup_close_ int etc_passwd_lock = -EBADF;
+ _cleanup_close_pair_ int
+ fd_inner_socket_pair[2] = EBADF_PAIR,
+ fd_outer_socket_pair[2] = EBADF_PAIR;
+
+ _cleanup_close_ int notify_socket = -EBADF, mntns_fd = -EBADF, fd_kmsg_fifo = -EBADF;
+ _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL;
+ _cleanup_(sd_event_source_unrefp) sd_event_source *notify_event_source = NULL;
+ _cleanup_(sd_event_unrefp) sd_event *event = NULL;
+ _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
+ _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
+ _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+ _cleanup_free_ uid_t *bind_user_uid = NULL;
+ size_t n_bind_user_uid = 0;
+ ContainerStatus container_status = 0;
+ int ifi = 0, r;
+ ssize_t l;
+ sigset_t mask_chld;
+ _cleanup_close_ int child_netns_fd = -EBADF;
+
+ 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, fd_inner_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create inner socket pair: %m");
+
+ if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, fd_outer_socket_pair) < 0)
+ return log_error_errno(errno, "Failed to create outer 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");
+
+ if (arg_network_namespace_path) {
+ child_netns_fd = open(arg_network_namespace_path, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+ if (child_netns_fd < 0)
+ return log_error_errno(errno, "Cannot open file %s: %m", arg_network_namespace_path);
+
+ r = fd_is_ns(child_netns_fd, CLONE_NEWNET);
+ if (r == -EUCLEAN)
+ log_debug_errno(r, "Cannot determine if passed network namespace path '%s' really refers to a network namespace, assuming it does.", arg_network_namespace_path);
+ else if (r < 0)
+ return log_error_errno(r, "Failed to check %s fs type: %m", arg_network_namespace_path);
+ else if (r == 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Path %s doesn't refer to a network namespace, refusing.", arg_network_namespace_path);
+ }
+
+ *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);
+
+ fd_inner_socket_pair[0] = safe_close(fd_inner_socket_pair[0]);
+ fd_outer_socket_pair[0] = safe_close(fd_outer_socket_pair[0]);
+
+ (void) reset_all_signal_handlers();
+ (void) reset_signal_mask();
+
+ r = outer_child(&barrier,
+ arg_directory,
+ dissected_image,
+ fd_outer_socket_pair[1],
+ fd_inner_socket_pair[1],
+ fds,
+ child_netns_fd);
+ if (r < 0)
+ _exit(EXIT_FAILURE);
+
+ _exit(EXIT_SUCCESS);
+ }
+
+ barrier_set_role(&barrier, BARRIER_PARENT);
+
+ fdset_close(fds);
+
+ fd_inner_socket_pair[1] = safe_close(fd_inner_socket_pair[1]);
+ fd_outer_socket_pair[1] = safe_close(fd_outer_socket_pair[1]);
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ mntns_fd = receive_one_fd(fd_outer_socket_pair[0], 0);
+ if (mntns_fd < 0)
+ return log_error_errno(mntns_fd, "Failed to receive mount namespace fd from outer child: %m");
+
+ /* The child just let us know the UID shift it might have read from the image. */
+ l = recv(fd_outer_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)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short read while reading UID shift.");
+
+ 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(fd_outer_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)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short write while writing UID shift.");
+ }
+
+ n_bind_user_uid = strv_length(arg_bind_user);
+ if (n_bind_user_uid > 0) {
+ /* Right after the UID shift, we'll receive the list of UID mappings for the
+ * --bind-user= logic. Always a quadruplet of payload and host UID + GID. */
+
+ bind_user_uid = new(uid_t, n_bind_user_uid*4);
+ if (!bind_user_uid)
+ return log_oom();
+
+ for (size_t i = 0; i < n_bind_user_uid; i++) {
+ l = recv(fd_outer_socket_pair[0], bind_user_uid + i*4, sizeof(uid_t)*4, 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to read user UID map pair: %m");
+ if (l != sizeof(uid_t)*4)
+ return log_full_errno(l == 0 ? LOG_DEBUG : LOG_WARNING,
+ SYNTHETIC_ERRNO(EIO),
+ "Short read while reading bind user UID pairs.");
+ }
+ }
+ }
+
+ if (arg_unified_cgroup_hierarchy == CGROUP_UNIFIED_UNKNOWN) {
+ /* The child let us know the support cgroup mode it might have read from the image. */
+ l = recv(fd_outer_socket_pair[0], &arg_unified_cgroup_hierarchy, sizeof(arg_unified_cgroup_hierarchy), 0);
+ if (l < 0)
+ return log_error_errno(errno, "Failed to read cgroup mode: %m");
+ if (l != sizeof(arg_unified_cgroup_hierarchy))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short read while reading cgroup mode (%zi bytes).%s",
+ l, l == 0 ? " The child is most likely dead." : "");
+ }
+
+ /* Wait for the outer child. */
+ r = wait_for_terminate_and_check("(sd-namespace)", *pid, WAIT_LOG_ABNORMAL);
+ if (r < 0)
+ return r;
+ if (r != EXIT_SUCCESS)
+ return -EIO;
+
+ /* And now retrieve the PID of the inner child. */
+ l = recv(fd_outer_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)
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short read while reading inner child PID.");
+
+ /* We also retrieve container UUID in case it was generated by outer child */
+ l = recv(fd_outer_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))
+ return log_error_errno(SYNTHETIC_ERRNO(EIO), "Short read while reading container machined ID.");
+
+ /* We also retrieve the socket used for notifications generated by outer child */
+ notify_socket = receive_one_fd(fd_outer_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 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Child died too early.");
+
+ r = setup_uid_map(*pid, bind_user_uid, n_bind_user_uid);
+ if (r < 0)
+ return r;
+
+ (void) barrier_place(&barrier); /* #2 */
+ }
+
+ if (arg_private_network) {
+ if (!arg_network_namespace_path) {
+ /* Wait until the child has unshared its network namespace. */
+ if (!barrier_place_and_sync(&barrier)) /* #3 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Child died too early");
+ }
+
+ if (child_netns_fd < 0) {
+ /* Make sure we have an open file descriptor to the child's network
+ * namespace so it stays alive even if the child exits. */
+ r = namespace_open(*pid, NULL, NULL, &child_netns_fd, NULL, NULL);
+ if (r < 0)
+ return log_error_errno(r, "Failed to open child network namespace: %m");
+ }
+
+ r = move_network_interfaces(child_netns_fd, 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, &arg_network_provided_mac);
+ 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 || !arg_keep_unit) {
+ r = sd_bus_default_system(&bus);
+ if (r < 0)
+ return log_error_errno(r, "Failed to open system bus: %m");
+
+ r = sd_bus_set_close_on_exit(bus, false);
+ if (r < 0)
+ return log_error_errno(r, "Failed to disable close-on-exit behaviour: %m");
+ }
+
+ if (!arg_keep_unit) {
+ /* When a new scope is created for this container, then we'll be registered as its controller, in which
+ * case PID 1 will send us a friendly RequestStop signal, when it is asked to terminate the
+ * scope. Let's hook into that, and cleanly shut down the container, and print a friendly message. */
+
+ r = sd_bus_match_signal_async(
+ bus,
+ NULL,
+ "org.freedesktop.systemd1",
+ NULL,
+ "org.freedesktop.systemd1.Scope",
+ "RequestStop",
+ on_request_stop, NULL, PID_TO_PTR(*pid));
+ if (r < 0)
+ return log_error_errno(r, "Failed to request RequestStop match: %m");
+ }
+
+ if (arg_register) {
+ r = register_machine(
+ bus,
+ arg_machine,
+ *pid,
+ arg_directory,
+ arg_uuid,
+ ifi,
+ arg_slice,
+ arg_custom_mounts, arg_n_custom_mounts,
+ arg_kill_signal,
+ arg_property,
+ arg_property_message,
+ arg_keep_unit,
+ arg_container_service_name,
+ arg_start_mode);
+ if (r < 0)
+ return r;
+
+ } else if (!arg_keep_unit) {
+ r = allocate_scope(
+ bus,
+ arg_machine,
+ *pid,
+ arg_slice,
+ arg_custom_mounts, arg_n_custom_mounts,
+ arg_kill_signal,
+ arg_property,
+ arg_property_message,
+ /* allow_pidfds= */ true,
+ arg_start_mode);
+ if (r < 0)
+ return r;
+
+ } else if (arg_slice || arg_property)
+ log_notice("Machine and scope registration turned off, --slice= and --property= settings will have no effect.");
+
+ r = create_subcgroup(*pid, arg_keep_unit, arg_unified_cgroup_hierarchy);
+ if (r < 0)
+ return r;
+
+ r = sync_cgroup(*pid, arg_unified_cgroup_hierarchy, arg_uid_shift);
+ if (r < 0)
+ return r;
+
+ r = chown_cgroup(*pid, arg_unified_cgroup_hierarchy, 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); /* #4 */
+
+ /* 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);
+ 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");
+
+ (void) sd_event_set_watchdog(event, true);
+
+ if (bus) {
+ r = sd_bus_attach_event(bus, event, 0);
+ if (r < 0)
+ return log_error_errno(r, "Failed to attach bus to event loop: %m");
+ }
+
+ r = setup_notify_parent(event, notify_socket, PID_TO_PTR(*pid), &notify_event_source);
+ if (r < 0)
+ return r;
+
+ /* Wait that the child is completely ready now, and has mounted their own copies of procfs and so on,
+ * before we take the fully visible instances away. */
+ if (!barrier_sync(&barrier)) /* #5.1 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Child died too early.");
+
+ if (arg_userns_mode != USER_NAMESPACE_NO) {
+ r = wipe_fully_visible_fs(mntns_fd);
+ if (r < 0)
+ return r;
+ mntns_fd = safe_close(mntns_fd);
+ }
+
+ /* And now let the child know that we completed removing the procfs instances, and it can start the
+ * payload. */
+ if (!barrier_place(&barrier)) /* #5.2 */
+ return log_error_errno(SYNTHETIC_ERRNO(ESRCH), "Child died too early.");
+
+ /* At this point we have made use of the UID we picked, and thus nss-systemd/systemd-machined.service
+ * will make them appear in getpwuid(), thus we can release the /etc/passwd lock. */
+ etc_passwd_lock = safe_close(etc_passwd_lock);
+
+ (void) sd_notifyf(false,
+ "STATUS=Container running.\n"
+ "X_NSPAWN_LEADER_PID=" PID_FMT, *pid);
+ if (!arg_notify_ready) {
+ r = sd_notify(false, "READY=1\n");
+ if (r < 0)
+ log_warning_errno(r, "Failed to send readiness notification, ignoring: %m");
+ }
+
+ if (arg_kill_signal > 0) {
+ /* Try to kill the init system on SIGINT or SIGTERM */
+ (void) sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(*pid));
+ (void) sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(*pid));
+ } else {
+ /* Immediately exit */
+ (void) sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+ (void) sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
+ }
+
+ (void) sd_event_add_signal(event, NULL, SIGRTMIN+18, sigrtmin18_handler, NULL);
+
+ r = sd_event_add_memory_pressure(event, NULL, NULL, NULL);
+ if (r < 0)
+ log_debug_errno(r, "Failed allocate memory pressure event source, ignoring: %m");
+
+ /* Exit when the child exits */
+ (void) sd_event_add_signal(event, NULL, SIGCHLD, on_sigchld, PID_TO_PTR(*pid));
+
+ /* Retrieve the kmsg fifo allocated by inner child */
+ fd_kmsg_fifo = receive_one_fd(fd_inner_socket_pair[0], 0);
+ if (fd_kmsg_fifo < 0)
+ return log_error_errno(fd_kmsg_fifo, "Failed to receive kmsg fifo from inner child: %m");
+
+ if (arg_expose_ports) {
+ r = expose_port_watch_rtnl(event, fd_inner_socket_pair[0], on_address_change, expose_args, &rtnl);
+ if (r < 0)
+ return r;
+
+ (void) expose_port_execute(rtnl, &expose_args->fw_ctx, arg_expose_ports, AF_INET, &expose_args->address4);
+ (void) expose_port_execute(rtnl, &expose_args->fw_ctx, arg_expose_ports, AF_INET6, &expose_args->address6);
+ }
+
+ if (arg_console_mode != CONSOLE_PIPE) {
+ _cleanup_close_ int fd = -EBADF;
+ PTYForwardFlags flags = 0;
+
+ /* Retrieve the master pty allocated by inner child */
+ fd = receive_one_fd(fd_inner_socket_pair[0], 0);
+ if (fd < 0)
+ return log_error_errno(fd, "Failed to receive master pty from the inner child: %m");
+
+ switch (arg_console_mode) {
+
+ case CONSOLE_READ_ONLY:
+ flags |= PTY_FORWARD_READ_ONLY;
+
+ _fallthrough_;
+
+ case CONSOLE_INTERACTIVE:
+ flags |= PTY_FORWARD_IGNORE_VHANGUP;
+
+ r = pty_forward_new(event, fd, flags, &forward);
+ if (r < 0)
+ return log_error_errno(r, "Failed to create PTY forwarder: %m");
+
+ if (arg_console_width != UINT_MAX || arg_console_height != UINT_MAX)
+ (void) pty_forward_set_width_height(forward,
+ arg_console_width,
+ arg_console_height);
+ break;
+
+ default:
+ assert(arg_console_mode == CONSOLE_PASSIVE);
+ }
+
+ *master = TAKE_FD(fd);
+ }
+
+ fd_inner_socket_pair[0] = safe_close(fd_inner_socket_pair[0]);
+
+ r = sd_event_loop(event);
+ if (r < 0)
+ return log_error_errno(r, "Failed to run event loop: %m");
+
+ if (forward) {
+ char last_char = 0;
+
+ (void) 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 && bus)
+ terminate_scope(bus, arg_machine);
+
+ /* Normally redundant, but better safe than sorry */
+ (void) kill(*pid, SIGKILL);
+
+ fd_kmsg_fifo = safe_close(fd_kmsg_fifo);
+
+ if (arg_private_network) {
+ /* Move network interfaces back to the parent network namespace. We use `safe_fork`
+ * to avoid having to move the parent to the child network namespace. */
+ r = safe_fork(NULL, FORK_RESET_SIGNALS|FORK_DEATHSIG_SIGTERM|FORK_WAIT|FORK_LOG, NULL);
+ if (r < 0)
+ return r;
+
+ if (r == 0) {
+ _cleanup_close_ int parent_netns_fd = -EBADF;
+
+ r = namespace_open(getpid_cached(), NULL, NULL, &parent_netns_fd, NULL, NULL);
+ if (r < 0) {
+ log_error_errno(r, "Failed to open parent network namespace: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ r = namespace_enter(-1, -1, child_netns_fd, -1, -1);
+ if (r < 0) {
+ log_error_errno(r, "Failed to enter child network namespace: %m");
+ _exit(EXIT_FAILURE);
+ }
+
+ /* Reverse network interfaces pair list so that interfaces get their initial name back.
+ * This is about ensuring interfaces get their old name back when being moved back. */
+ arg_network_interfaces = strv_reverse(arg_network_interfaces);
+
+ r = move_network_interfaces(parent_netns_fd, arg_network_interfaces);
+ if (r < 0)
+ log_error_errno(r, "Failed to move network interfaces back to parent network namespace: %m");
+
+ _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+ }
+ }
+
+ r = wait_for_container(TAKE_PID(*pid), &container_status);
+
+ /* Tell machined that we are gone. */
+ if (bus)
+ (void) unregister_machine(bus, arg_machine);
+
+ 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 == EXIT_FORCE_RESTART)
+ 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 = EXIT_FORCE_RESTART;
+ return 0; /* finito */
+ }
+
+ expose_port_flush(&expose_args->fw_ctx, arg_expose_ports, AF_INET, &expose_args->address4);
+ expose_port_flush(&expose_args->fw_ctx, arg_expose_ports, AF_INET6, &expose_args->address6);
+
+ (void) remove_veth_links(veth_name, arg_network_veth_extra);
+ *veth_created = false;
+ return 1; /* loop again */
+}
+
+static int initialize_rlimits(void) {
+ /* The default resource limits the kernel passes to PID 1, as per kernel 5.16. Let's pass our container payload
+ * the same values as the kernel originally passed to PID 1, in order to minimize differences between host and
+ * container execution environments. */
+
+ static const struct rlimit kernel_defaults[_RLIMIT_MAX] = {
+ [RLIMIT_AS] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_CORE] = { 0, RLIM_INFINITY },
+ [RLIMIT_CPU] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_DATA] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_FSIZE] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_LOCKS] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_MEMLOCK] = { DEFAULT_RLIMIT_MEMLOCK, DEFAULT_RLIMIT_MEMLOCK },
+ [RLIMIT_MSGQUEUE] = { 819200, 819200 },
+ [RLIMIT_NICE] = { 0, 0 },
+ [RLIMIT_NOFILE] = { 1024, 4096 },
+ [RLIMIT_RSS] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_RTPRIO] = { 0, 0 },
+ [RLIMIT_RTTIME] = { RLIM_INFINITY, RLIM_INFINITY },
+ [RLIMIT_STACK] = { 8388608, RLIM_INFINITY },
+
+ /* The kernel scales the default for RLIMIT_NPROC and RLIMIT_SIGPENDING based on the system's amount of
+ * RAM. To provide best compatibility we'll read these limits off PID 1 instead of hardcoding them
+ * here. This is safe as we know that PID 1 doesn't change these two limits and thus the original
+ * kernel's initialization should still be valid during runtime — at least if PID 1 is systemd. Note
+ * that PID 1 changes a number of other resource limits during early initialization which is why we
+ * don't read the other limits from PID 1 but prefer the static table above. */
+ };
+
+ int rl;
+
+ for (rl = 0; rl < _RLIMIT_MAX; rl++) {
+ /* Let's only fill in what the user hasn't explicitly configured anyway */
+ if ((arg_settings_mask & (SETTING_RLIMIT_FIRST << rl)) == 0) {
+ const struct rlimit *v;
+ struct rlimit buffer;
+
+ if (IN_SET(rl, RLIMIT_NPROC, RLIMIT_SIGPENDING)) {
+ /* For these two let's read the limits off PID 1. See above for an explanation. */
+
+ if (prlimit(1, rl, NULL, &buffer) < 0)
+ return log_error_errno(errno, "Failed to read resource limit RLIMIT_%s of PID 1: %m", rlimit_to_string(rl));
+
+ v = &buffer;
+ } else if (rl == RLIMIT_NOFILE) {
+ /* We nowadays bump RLIMIT_NOFILE's hard limit early in PID 1 for all
+ * userspace. Given that nspawn containers are often run without our PID 1,
+ * let's grant the containers a raised RLIMIT_NOFILE hard limit by default,
+ * so that container userspace gets similar resources as host userspace
+ * gets. */
+ buffer = kernel_defaults[rl];
+ buffer.rlim_max = MIN((rlim_t) read_nr_open(), (rlim_t) HIGH_RLIMIT_NOFILE);
+ v = &buffer;
+ } else
+ v = kernel_defaults + rl;
+
+ arg_rlimit[rl] = newdup(struct rlimit, v, 1);
+ if (!arg_rlimit[rl])
+ return log_oom();
+ }
+
+ if (DEBUG_LOGGING) {
+ _cleanup_free_ char *k = NULL;
+
+ (void) rlimit_format(arg_rlimit[rl], &k);
+ log_debug("Setting RLIMIT_%s to %s.", rlimit_to_string(rl), k);
+ }
+ }
+
+ return 0;
+}
+
+static int cant_be_in_netns(void) {
+ _cleanup_close_ int fd = -EBADF;
+ struct ucred ucred;
+ int r;
+
+ /* Check if we are in the same netns as udev. If we aren't, then device monitoring (and thus waiting
+ * for loopback block devices) won't work, and we will hang. Detect this case and exit early with a
+ * nice message. */
+
+ if (!arg_image) /* only matters if --image= us used, i.e. we actually need to use loopback devices */
+ return 0;
+
+ fd = socket(AF_UNIX, SOCK_SEQPACKET|SOCK_NONBLOCK|SOCK_CLOEXEC, 0);
+ if (fd < 0)
+ return log_error_errno(errno, "Failed to allocate udev control socket: %m");
+
+ r = connect_unix_path(fd, AT_FDCWD, "/run/udev/control");
+ if (r == -ENOENT || ERRNO_IS_NEG_DISCONNECT(r))
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "Sorry, but --image= requires access to the host's /run/ hierarchy, since we need access to udev.");
+ if (r < 0)
+ return log_error_errno(r, "Failed to connect socket to udev control socket: %m");
+
+ r = getpeercred(fd, &ucred);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine peer of udev control socket: %m");
+
+ r = in_same_namespace(ucred.pid, 0, NAMESPACE_NET);
+ if (r < 0)
+ return log_error_errno(r, "Failed to determine network namespace of udev: %m");
+ if (r == 0)
+ return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
+ "Sorry, but --image= is only supported in the main network namespace, since we need access to udev/AF_NETLINK.");
+ return 0;
+}
+
+static int run(int argc, char *argv[]) {
+ bool remove_directory = false, remove_image = false, veth_created = false, remove_tmprootdir = false;
+ _cleanup_close_ int master = -EBADF;
+ _cleanup_fdset_free_ FDSet *fds = NULL;
+ int r, n_fd_passed, ret = EXIT_SUCCESS;
+ char veth_name[IFNAMSIZ] = "";
+ struct ExposeArgs expose_args = {};
+ _cleanup_(release_lock_file) LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT;
+ char tmprootdir[] = "/tmp/nspawn-root-XXXXXX";
+ _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
+ _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL;
+ _cleanup_(fw_ctx_freep) FirewallContext *fw_ctx = NULL;
+ pid_t pid = 0;
+
+ log_parse_environment();
+ log_open();
+
+ r = parse_argv(argc, argv);
+ if (r <= 0)
+ goto finish;
+
+ if (geteuid() != 0) {
+ r = log_warning_errno(SYNTHETIC_ERRNO(EPERM),
+ argc >= 2 ? "Need to be root." :
+ "Need to be root (and some arguments are usually required).\nHint: try --help");
+ goto finish;
+ }
+
+ r = cant_be_in_netns();
+ if (r < 0)
+ goto finish;
+
+ r = initialize_rlimits();
+ if (r < 0)
+ goto finish;
+
+ r = load_oci_bundle();
+ if (r < 0)
+ goto finish;
+
+ r = determine_names();
+ if (r < 0)
+ goto finish;
+
+ r = load_settings();
+ if (r < 0)
+ goto finish;
+
+ /* If we're not unsharing the network namespace and are unsharing the user namespace, we won't have
+ * permissions to bind ports in the container, so let's drop the CAP_NET_BIND_SERVICE capability to
+ * indicate that. */
+ if (!arg_private_network && arg_userns_mode != USER_NAMESPACE_NO && arg_uid_shift > 0)
+ arg_caps_retain &= ~(UINT64_C(1) << CAP_NET_BIND_SERVICE);
+
+ r = cg_unified();
+ if (r < 0) {
+ log_error_errno(r, "Failed to determine whether the unified cgroups hierarchy is used: %m");
+ goto finish;
+ }
+
+ r = verify_arguments();
+ if (r < 0)
+ goto finish;
+
+ r = verify_network_interfaces_initialized();
+ if (r < 0)
+ goto finish;
+
+ /* Reapply environment settings. */
+ (void) detect_unified_cgroup_hierarchy_from_environment();
+
+ /* Ignore SIGPIPE here, because we use splice() on the ptyfwd stuff and that will generate SIGPIPE if
+ * the result is closed. Note that the container payload child will reset signal mask+handler anyway,
+ * so just turning this off here means we only turn it off in nspawn itself, not any children. */
+ (void) ignore_signals(SIGPIPE);
+
+ n_fd_passed = sd_listen_fds(false);
+ if (n_fd_passed > 0) {
+ r = fdset_new_listen_fds(&fds, false);
+ if (r < 0) {
+ log_error_errno(r, "Failed to collect file descriptors: %m");
+ goto finish;
+ }
+ }
+
+ /* The "default" umask. This is appropriate for most file and directory
+ * operations performed by nspawn, and is the umask that will be used for
+ * the child. Functions like copy_devnodes() change the umask temporarily. */
+ umask(0022);
+
+ if (arg_directory) {
+ assert(!arg_image);
+
+ /* Safety precaution: let's not allow running images from the live host OS image, as long as
+ * /var from the host will propagate into container dynamically (because bad things happen if
+ * two systems write to the same /var). Let's allow it for the special cases where /var is
+ * either copied (i.e. --ephemeral) or replaced (i.e. --volatile=yes|state). */
+ if (path_equal(arg_directory, "/") && !(arg_ephemeral || IN_SET(arg_volatile_mode, VOLATILE_YES, VOLATILE_STATE))) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Spawning container on root directory is not supported. Consider using --ephemeral, --volatile=yes or --volatile=state.");
+ goto finish;
+ }
+
+ if (arg_ephemeral) {
+ _cleanup_free_ char *np = NULL;
+
+ r = chase_and_update(&arg_directory, 0);
+ if (r < 0)
+ goto finish;
+
+ /* If the specified path is a mount point we generate the new snapshot immediately
+ * inside it under a random name. However if the specified is not a mount point we
+ * create the new snapshot in the parent directory, just next to it. */
+ r = path_is_mount_point(arg_directory, NULL, 0);
+ if (r < 0) {
+ log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory);
+ goto finish;
+ }
+ if (r > 0)
+ r = tempfn_random_child(arg_directory, "machine.", &np);
+ else
+ r = tempfn_random(arg_directory, "machine.", &np);
+ if (r < 0) {
+ log_error_errno(r, "Failed to generate name for directory snapshot: %m");
+ goto finish;
+ }
+
+ /* We take an exclusive lock on this image, since it's our private, ephemeral copy
+ * only owned by us and no one else. */
+ r = image_path_lock(np, LOCK_EX|LOCK_NB, &tree_global_lock, &tree_local_lock);
+ if (r < 0) {
+ log_error_errno(r, "Failed to lock %s: %m", np);
+ goto finish;
+ }
+
+ {
+ BLOCK_SIGNALS(SIGINT);
+ r = btrfs_subvol_snapshot_at(AT_FDCWD, arg_directory, AT_FDCWD, np,
+ (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
+ BTRFS_SNAPSHOT_FALLBACK_COPY |
+ BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
+ BTRFS_SNAPSHOT_RECURSIVE |
+ BTRFS_SNAPSHOT_QUOTA |
+ BTRFS_SNAPSHOT_SIGINT);
+ }
+ if (r == -EINTR) {
+ log_error_errno(r, "Interrupted while copying file system tree to %s, removed again.", np);
+ goto finish;
+ }
+ if (r < 0) {
+ log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory);
+ goto finish;
+ }
+
+ free_and_replace(arg_directory, np);
+ remove_directory = true;
+ } else {
+ r = chase_and_update(&arg_directory, arg_template ? CHASE_NONEXISTENT : 0);
+ if (r < 0)
+ goto finish;
+
+ r = image_path_lock(arg_directory, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
+ if (r == -EBUSY) {
+ log_error_errno(r, "Directory tree %s is currently busy.", arg_directory);
+ goto finish;
+ }
+ if (r < 0) {
+ log_error_errno(r, "Failed to lock %s: %m", arg_directory);
+ goto finish;
+ }
+
+ if (arg_template) {
+ r = chase_and_update(&arg_template, 0);
+ if (r < 0)
+ goto finish;
+
+ {
+ BLOCK_SIGNALS(SIGINT);
+ r = btrfs_subvol_snapshot_at(AT_FDCWD, arg_template, AT_FDCWD, arg_directory,
+ (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
+ BTRFS_SNAPSHOT_FALLBACK_COPY |
+ BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
+ BTRFS_SNAPSHOT_FALLBACK_IMMUTABLE |
+ BTRFS_SNAPSHOT_RECURSIVE |
+ BTRFS_SNAPSHOT_QUOTA |
+ BTRFS_SNAPSHOT_SIGINT);
+ }
+ if (r == -EEXIST)
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO,
+ "Directory %s already exists, not populating from template %s.", arg_directory, arg_template);
+ else if (r == -EINTR) {
+ log_error_errno(r, "Interrupted while copying file system tree to %s, removed again.", arg_directory);
+ goto finish;
+ } else if (r < 0) {
+ log_error_errno(r, "Couldn't create snapshot %s from %s: %m", arg_directory, arg_template);
+ goto finish;
+ } else
+ log_full(arg_quiet ? LOG_DEBUG : LOG_INFO,
+ "Populated %s from template %s.", arg_directory, arg_template);
+ }
+ }
+
+ if (arg_start_mode == START_BOOT) {
+ _cleanup_free_ char *b = NULL;
+ const char *p;
+ int check_os_release, is_os_tree;
+
+ if (arg_pivot_root_new) {
+ b = path_join(arg_directory, arg_pivot_root_new);
+ if (!b) {
+ r = log_oom();
+ goto finish;
+ }
+
+ p = b;
+ } else
+ p = arg_directory;
+
+ check_os_release = getenv_bool("SYSTEMD_NSPAWN_CHECK_OS_RELEASE");
+ if (check_os_release < 0 && check_os_release != -ENXIO) {
+ r = log_error_errno(check_os_release, "Failed to parse $SYSTEMD_NSPAWN_CHECK_OS_RELEASE: %m");
+ goto finish;
+ }
+
+ is_os_tree = path_is_os_tree(p);
+ if (is_os_tree == 0 && check_os_release == 0)
+ log_debug("Directory %s is missing an os-release file, continuing anyway.", p);
+ else if (is_os_tree <= 0) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", p);
+ goto finish;
+ }
+ } else {
+ _cleanup_free_ char *p = NULL;
+
+ if (arg_pivot_root_new)
+ p = path_join(arg_directory, arg_pivot_root_new, "/usr/");
+ else
+ p = path_join(arg_directory, "/usr/");
+ if (!p) {
+ r = log_oom();
+ goto finish;
+ }
+
+ if (laccess(p, F_OK) < 0) {
+ r = log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Directory %s doesn't look like it has an OS tree (/usr/ directory is missing). Refusing.", arg_directory);
+ goto finish;
+ }
+ }
+
+ } else {
+ DissectImageFlags dissect_image_flags =
+ DISSECT_IMAGE_GENERIC_ROOT |
+ DISSECT_IMAGE_REQUIRE_ROOT |
+ DISSECT_IMAGE_RELAX_VAR_CHECK |
+ DISSECT_IMAGE_USR_NO_ROOT |
+ DISSECT_IMAGE_ADD_PARTITION_DEVICES |
+ DISSECT_IMAGE_PIN_PARTITION_DEVICES;
+ assert(arg_image);
+ assert(!arg_template);
+
+ r = chase_and_update(&arg_image, 0);
+ if (r < 0)
+ goto finish;
+
+ if (arg_ephemeral) {
+ _cleanup_free_ char *np = NULL;
+
+ r = tempfn_random(arg_image, "machine.", &np);
+ if (r < 0) {
+ log_error_errno(r, "Failed to generate name for image snapshot: %m");
+ goto finish;
+ }
+
+ /* Always take an exclusive lock on our own ephemeral copy. */
+ r = image_path_lock(np, LOCK_EX|LOCK_NB, &tree_global_lock, &tree_local_lock);
+ if (r < 0) {
+ r = log_error_errno(r, "Failed to create image lock: %m");
+ goto finish;
+ }
+
+ {
+ BLOCK_SIGNALS(SIGINT);
+ r = copy_file_full(arg_image, np, O_EXCL, arg_read_only ? 0400 : 0600,
+ FS_NOCOW_FL, FS_NOCOW_FL,
+ COPY_REFLINK|COPY_CRTIME|COPY_SIGINT,
+ NULL, NULL);
+ }
+ if (r == -EINTR) {
+ log_error_errno(r, "Interrupted while copying image file to %s, removed again.", np);
+ goto finish;
+ }
+ if (r < 0) {
+ r = log_error_errno(r, "Failed to copy image file: %m");
+ goto finish;
+ }
+
+ free_and_replace(arg_image, np);
+ remove_image = true;
+ } else {
+ r = image_path_lock(arg_image, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock);
+ if (r == -EBUSY) {
+ r = log_error_errno(r, "Disk image %s is currently busy.", arg_image);
+ goto finish;
+ }
+ if (r < 0) {
+ r = log_error_errno(r, "Failed to create image lock: %m");
+ goto finish;
+ }
+
+ r = verity_settings_load(
+ &arg_verity_settings,
+ arg_image, NULL, NULL);
+ if (r < 0) {
+ log_error_errno(r, "Failed to read verity artefacts for %s: %m", arg_image);
+ goto finish;
+ }
+
+ if (arg_verity_settings.data_path)
+ dissect_image_flags |= DISSECT_IMAGE_NO_PARTITION_TABLE;
+ }
+
+ if (!mkdtemp(tmprootdir)) {
+ r = log_error_errno(errno, "Failed to create temporary directory: %m");
+ goto finish;
+ }
+
+ remove_tmprootdir = true;
+
+ arg_directory = strdup(tmprootdir);
+ if (!arg_directory) {
+ r = log_oom();
+ goto finish;
+ }
+
+ r = loop_device_make_by_path(
+ arg_image,
+ arg_read_only ? O_RDONLY : O_RDWR,
+ /* sector_size= */ UINT32_MAX,
+ FLAGS_SET(dissect_image_flags, DISSECT_IMAGE_NO_PARTITION_TABLE) ? 0 : LO_FLAGS_PARTSCAN,
+ LOCK_SH,
+ &loop);
+ if (r < 0) {
+ log_error_errno(r, "Failed to set up loopback block device: %m");
+ goto finish;
+ }
+
+ r = dissect_loop_device_and_warn(
+ loop,
+ &arg_verity_settings,
+ /* mount_options=*/ NULL,
+ arg_image_policy ?: &image_policy_container,
+ dissect_image_flags,
+ &dissected_image);
+ if (r == -ENOPKG) {
+ /* dissected_image_and_warn() already printed a brief error message. Extend on that with more details */
+ log_notice("Note that the disk image needs to\n"
+ " a) either contain only a single MBR partition of type 0x83 that is marked bootable\n"
+ " b) or contain a single GPT partition of type 0FC63DAF-8483-4772-8E79-3D69D8477DE4\n"
+ " c) or follow https://uapi-group.org/specifications/specs/discoverable_partitions_specification\n"
+ " d) or contain a file system without a partition table\n"
+ "in order to be bootable with systemd-nspawn.");
+ goto finish;
+ }
+ if (r < 0)
+ goto finish;
+
+ r = dissected_image_load_verity_sig_partition(
+ dissected_image,
+ loop->fd,
+ &arg_verity_settings);
+ if (r < 0)
+ goto finish;
+
+ if (dissected_image->has_verity && !arg_verity_settings.root_hash && !dissected_image->has_verity_sig)
+ log_notice("Note: image %s contains verity information, but no root hash specified and no embedded "
+ "root hash signature found! Proceeding without integrity checking.", arg_image);
+
+ r = dissected_image_decrypt_interactively(
+ dissected_image,
+ NULL,
+ &arg_verity_settings,
+ 0);
+ if (r < 0)
+ goto finish;
+
+ /* Now that we mounted the image, let's try to remove it again, if it is ephemeral */
+ if (remove_image && unlink(arg_image) >= 0)
+ remove_image = false;
+
+ if (arg_architecture < 0)
+ arg_architecture = dissected_image_architecture(dissected_image);
+ }
+
+ r = custom_mount_prepare_all(arg_directory, arg_custom_mounts, arg_n_custom_mounts);
+ if (r < 0)
+ goto finish;
+
+ if (arg_console_mode < 0)
+ arg_console_mode =
+ isatty(STDIN_FILENO) > 0 &&
+ isatty(STDOUT_FILENO) > 0 ? CONSOLE_INTERACTIVE : CONSOLE_READ_ONLY;
+
+ if (arg_console_mode == CONSOLE_PIPE) /* if we pass STDERR on to the container, don't add our own logs into it too */
+ arg_quiet = true;
+
+ if (!arg_quiet)
+ log_info("Spawning container %s on %s.\nPress Ctrl-] three times within 1s to kill container.",
+ arg_machine, arg_image ?: arg_directory);
+
+ assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, SIGRTMIN+18, -1) >= 0);
+
+ r = make_reaper_process(true);
+ if (r < 0) {
+ log_error_errno(r, "Failed to become subreaper: %m");
+ goto finish;
+ }
+
+ if (arg_expose_ports) {
+ r = fw_ctx_new(&fw_ctx);
+ if (r < 0) {
+ log_error_errno(r, "Cannot expose configured ports, firewall initialization failed: %m");
+ goto finish;
+ }
+ expose_args.fw_ctx = fw_ctx;
+ }
+ for (;;) {
+ r = run_container(dissected_image,
+ fds,
+ veth_name, &veth_created,
+ &expose_args, &master,
+ &pid, &ret);
+ if (r <= 0)
+ break;
+ }
+
+finish:
+ (void) sd_notify(false,
+ r == 0 && ret == EXIT_FORCE_RESTART ? "STOPPING=1\nSTATUS=Restarting..." :
+ "STOPPING=1\nSTATUS=Terminating...");
+
+ if (pid > 0)
+ (void) kill(pid, SIGKILL);
+
+ /* Try to flush whatever is still queued in the pty */
+ if (master >= 0) {
+ (void) copy_bytes(master, STDOUT_FILENO, UINT64_MAX, 0);
+ master = safe_close(master);
+ }
+
+ if (pid > 0)
+ (void) wait_for_terminate(pid, NULL);
+
+ pager_close();
+
+ if (remove_directory && arg_directory) {
+ int k;
+
+ k = rm_rf(arg_directory, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
+ if (k < 0)
+ log_warning_errno(k, "Cannot remove '%s', ignoring: %m", arg_directory);
+ }
+
+ if (remove_image && arg_image) {
+ if (unlink(arg_image) < 0)
+ log_warning_errno(errno, "Can't remove image file '%s', ignoring: %m", arg_image);
+ }
+
+ if (remove_tmprootdir) {
+ if (rmdir(tmprootdir) < 0)
+ log_debug_errno(errno, "Can't remove temporary root directory '%s', ignoring: %m", tmprootdir);
+ }
+
+ if (arg_machine) {
+ const char *p;
+
+ p = strjoina("/run/systemd/nspawn/propagate/", arg_machine);
+ (void) rm_rf(p, REMOVE_ROOT);
+ }
+
+ expose_port_flush(&fw_ctx, arg_expose_ports, AF_INET, &expose_args.address4);
+ expose_port_flush(&fw_ctx, arg_expose_ports, AF_INET6, &expose_args.address6);
+
+ if (veth_created)
+ (void) remove_veth_links(veth_name, arg_network_veth_extra);
+ (void) remove_bridge(arg_network_zone);
+
+ custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts);
+ expose_port_free_all(arg_expose_ports);
+ rlimit_free_all(arg_rlimit);
+ device_node_array_free(arg_extra_nodes, arg_n_extra_nodes);
+ machine_credential_free_all(arg_credentials, arg_n_credentials);
+
+ if (r < 0)
+ return r;
+
+ return ret;
+}
+
+DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-20 10:09:43 +0000