chiark / gitweb /
machinectl: implement "bind" command to create additional bind mounts from host to...
[elogind.git] / src / machine / machinectl.c
index d812ef2600dcd08e30f344f1c5f5b17c6258336a..2571fc0c71dee427724e8e8bd4ed9d82015f2100 100644 (file)
 #include <pwd.h>
 #include <locale.h>
 #include <fcntl.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <sys/mount.h>
 
 #include "sd-bus.h"
 #include "log.h"
@@ -41,6 +45,9 @@
 #include "cgroup-show.h"
 #include "cgroup-util.h"
 #include "ptyfwd.h"
+#include "event-util.h"
+#include "path-util.h"
+#include "mkdir.h"
 
 static char **arg_property = NULL;
 static bool arg_all = false;
@@ -51,6 +58,8 @@ static const char *arg_kill_who = NULL;
 static int arg_signal = SIGTERM;
 static BusTransport arg_transport = BUS_TRANSPORT_LOCAL;
 static char *arg_host = NULL;
+static bool arg_read_only = false;
+static bool arg_mkdir = false;
 
 static void pager_open_if_enabled(void) {
 
@@ -165,6 +174,109 @@ static int show_unit_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
         return 0;
 }
 
+static int print_addresses(sd_bus *bus, const char *name, int ifi, const char *prefix, const char *prefix2) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        int r;
+
+        assert(bus);
+        assert(name);
+        assert(prefix);
+        assert(prefix2);
+
+        r = sd_bus_call_method(bus,
+                               "org.freedesktop.machine1",
+                               "/org/freedesktop/machine1",
+                               "org.freedesktop.machine1.Manager",
+                               "GetMachineAddresses",
+                               NULL,
+                               &reply,
+                               "s", name);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_enter_container(reply, 'a', "(iay)");
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        while ((r = sd_bus_message_enter_container(reply, 'r', "iay")) > 0) {
+                int family;
+                const void *a;
+                size_t sz;
+                char buffer[MAX(INET6_ADDRSTRLEN, INET_ADDRSTRLEN)];
+
+                r = sd_bus_message_read(reply, "i", &family);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_array(reply, 'y', &a, &sz);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                fputs(prefix, stdout);
+                fputs(inet_ntop(family, a, buffer, sizeof(buffer)), stdout);
+                if (family == AF_INET6 && ifi > 0)
+                        printf("%%%i", ifi);
+                fputc('\n', stdout);
+
+                r = sd_bus_message_exit_container(reply);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                if (prefix != prefix2)
+                        prefix = prefix2;
+        }
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_message_exit_container(reply);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        return 0;
+}
+
+static int print_os_release(sd_bus *bus, const char *name, const char *prefix) {
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        const char *k, *v, *pretty = NULL;
+        int r;
+
+        assert(bus);
+        assert(name);
+        assert(prefix);
+
+        r = sd_bus_call_method(bus,
+                               "org.freedesktop.machine1",
+                               "/org/freedesktop/machine1",
+                               "org.freedesktop.machine1.Manager",
+                               "GetMachineOSRelease",
+                               NULL,
+                               &reply,
+                               "s", name);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_enter_container(reply, 'a', "{ss}");
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        while ((r = sd_bus_message_read(reply, "{ss}", &k, &v)) > 0) {
+                if (streq(k, "PRETTY_NAME"))
+                        pretty = v;
+
+        }
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_message_exit_container(reply);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        if (pretty)
+                printf("%s%s\n", prefix, pretty);
+
+        return 0;
+}
+
 typedef struct MachineStatusInfo {
         char *name;
         sd_id128_t id;
@@ -174,11 +286,15 @@ typedef struct MachineStatusInfo {
         char *root_directory;
         pid_t leader;
         usec_t timestamp;
+        int *netif;
+        unsigned n_netif;
 } MachineStatusInfo;
 
 static void print_machine_status_info(sd_bus *bus, MachineStatusInfo *i) {
         char since1[FORMAT_TIMESTAMP_RELATIVE_MAX], *s1;
         char since2[FORMAT_TIMESTAMP_MAX], *s2;
+        int ifi = -1;
+
         assert(i);
 
         fputs(strna(i->name), stdout);
@@ -221,23 +337,74 @@ static void print_machine_status_info(sd_bus *bus, MachineStatusInfo *i) {
         if (i->root_directory)
                 printf("\t    Root: %s\n", i->root_directory);
 
+        if (i->n_netif > 0) {
+                unsigned c;
+
+                fputs("\t   Iface:", stdout);
+
+                for (c = 0; c < i->n_netif; c++) {
+                        char name[IF_NAMESIZE+1] = "";
+
+                        if (if_indextoname(i->netif[c], name)) {
+                                fputc(' ', stdout);
+                                fputs(name, stdout);
+
+                                if (ifi < 0)
+                                        ifi = i->netif[c];
+                                else
+                                        ifi = 0;
+                        } else
+                                printf(" %i", i->netif[c]);
+                }
+
+                fputc('\n', stdout);
+        }
+
+        print_addresses(bus, i->name, ifi,
+                       "\t Address: ",
+                       "\t          ");
+
+        print_os_release(bus, i->name, "\t      OS: ");
+
         if (i->unit) {
                 printf("\t    Unit: %s\n", i->unit);
                 show_unit_cgroup(bus, i->unit, i->leader);
         }
 }
 
+static int map_netif(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_error *error, void *userdata) {
+        MachineStatusInfo *i = userdata;
+        size_t l;
+        const void *v;
+        int r;
+
+        assert_cc(sizeof(int32_t) == sizeof(int));
+        r = sd_bus_message_read_array(m, SD_BUS_TYPE_INT32, &v, &l);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EBADMSG;
+
+        i->n_netif = l / sizeof(int32_t);
+        i->netif = memdup(v, l);
+        if (!i->netif)
+                return -ENOMEM;
+
+        return 0;
+}
+
 static int show_info(const char *verb, sd_bus *bus, const char *path, bool *new_line) {
 
         static const struct bus_properties_map map[]  = {
-                { "Name",          "s",  NULL,          offsetof(MachineStatusInfo, name) },
-                { "Class",         "s",  NULL,          offsetof(MachineStatusInfo, class) },
-                { "Service",       "s",  NULL,          offsetof(MachineStatusInfo, service) },
-                { "Unit",          "s",  NULL,          offsetof(MachineStatusInfo, unit) },
-                { "RootDirectory", "s",  NULL,          offsetof(MachineStatusInfo, root_directory) },
-                { "Leader",        "u",  NULL,          offsetof(MachineStatusInfo, leader) },
-                { "Timestamp",     "t",  NULL,          offsetof(MachineStatusInfo, timestamp) },
-                { "Id",            "ay", bus_map_id128, offsetof(MachineStatusInfo, id) },
+                { "Name",              "s",  NULL,          offsetof(MachineStatusInfo, name) },
+                { "Class",             "s",  NULL,          offsetof(MachineStatusInfo, class) },
+                { "Service",           "s",  NULL,          offsetof(MachineStatusInfo, service) },
+                { "Unit",              "s",  NULL,          offsetof(MachineStatusInfo, unit) },
+                { "RootDirectory",     "s",  NULL,          offsetof(MachineStatusInfo, root_directory) },
+                { "Leader",            "u",  NULL,          offsetof(MachineStatusInfo, leader) },
+                { "Timestamp",         "t",  NULL,          offsetof(MachineStatusInfo, timestamp) },
+                { "Id",                "ay", bus_map_id128, offsetof(MachineStatusInfo, id) },
+                { "NetworkInterfaces", "ai", map_netif,     0 },
                 {}
         };
 
@@ -252,10 +419,8 @@ static int show_info(const char *verb, sd_bus *bus, const char *path, bool *new_
                                    path,
                                    map,
                                    &info);
-        if (r < 0) {
-                log_error("Could not get properties: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Could not get properties: %m");
 
         if (*new_line)
                 printf("\n");
@@ -268,6 +433,7 @@ static int show_info(const char *verb, sd_bus *bus, const char *path, bool *new_
         free(info.service);
         free(info.unit);
         free(info.root_directory);
+        free(info.netif);
 
         return r;
 }
@@ -282,7 +448,7 @@ static int show_properties(sd_bus *bus, const char *path, bool *new_line) {
 
         r = bus_print_all_properties(bus, "org.freedesktop.machine1", path, arg_property, arg_all);
         if (r < 0)
-                log_error("Could not get properties: %s", strerror(-r));
+                log_error_errno(r, "Could not get properties: %m");
 
         return r;
 }
@@ -411,8 +577,243 @@ static int terminate_machine(sd_bus *bus, char **args, unsigned n) {
         return 0;
 }
 
+static int machine_get_leader(sd_bus *bus, const char *name, pid_t *ret) {
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL, *reply2 = NULL;
+        const char *object;
+        uint32_t leader;
+        int r;
+
+        assert(bus);
+        assert(name);
+        assert(ret);
+
+        r = sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.machine1",
+                        "/org/freedesktop/machine1",
+                        "org.freedesktop.machine1.Manager",
+                        "GetMachine",
+                        &error,
+                        &reply,
+                        "s", name);
+        if (r < 0) {
+                log_error("Could not get path to machine: %s", bus_error_message(&error, -r));
+                return r;
+        }
+
+        r = sd_bus_message_read(reply, "o", &object);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_get_property(
+                        bus,
+                        "org.freedesktop.machine1",
+                        object,
+                        "org.freedesktop.machine1.Machine",
+                        "Leader",
+                        &error,
+                        &reply2,
+                        "u");
+        if (r < 0)
+                return log_error_errno(r, "Failed to retrieve PID of leader: %m");
+
+        r = sd_bus_message_read(reply2, "u", &leader);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        *ret = leader;
+        return 0;
+}
+
+static int bind_mount(sd_bus *bus, char **args, unsigned n) {
+        char mount_slave[] = "/tmp/propagate.XXXXXX", *mount_tmp, *mount_outside, *p;
+        pid_t child, leader;
+        const char *dest;
+        siginfo_t si;
+        bool mount_slave_created = false, mount_slave_mounted = false,
+                mount_tmp_created = false, mount_tmp_mounted = false,
+                mount_outside_created = false, mount_outside_mounted = false;
+        int r;
+
+        /* One day, when bind mounting /proc/self/fd/n works across
+         * namespace boundaries we should rework this logic to make
+         * use of it... */
+
+        if (n > 4) {
+                log_error("Too many arguments.");
+                return -EINVAL;
+        }
+
+        dest = args[3] ?: args[2];
+        if (!path_is_absolute(dest)) {
+                log_error("Destination path not absolute.");
+                return -EINVAL;
+        }
+
+        p = strappenda("/run/systemd/nspawn/propagate/", args[1], "/");
+        if (access(p, F_OK) < 0) {
+                log_error("Container does not allow propagation of mount points.");
+                return -ENOTSUP;
+        }
+
+        r = machine_get_leader(bus, args[1], &leader);
+        if (r < 0)
+                return r;
+
+        /* Our goal is to install a new bind mount into the container,
+           possibly read-only. This is irritatingly complex
+           unfortunately, currently.
+
+           First, we start by creating a private playground in /tmp,
+           that we can mount MS_SLAVE. (Which is necessary, since
+           MS_MOUNT cannot be applied to mounts with MS_SHARED parent
+           mounts.) */
+
+        if (!mkdtemp(mount_slave))
+                return log_error_errno(errno, "Failed to create playground: %m");
+
+        mount_slave_created = true;
+
+        if (mount(mount_slave, mount_slave, NULL, MS_BIND, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to make bind mount: %m");
+                goto finish;
+        }
+
+        mount_slave_mounted = true;
+
+        if (mount(NULL, mount_slave, NULL, MS_SLAVE, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to remount slave: %m");
+                goto finish;
+        }
+
+        /* Second, we mount the source directory to a directory inside
+           of our MS_SLAVE playground. */
+        mount_tmp = strappenda(mount_slave, "/mount");
+        if (mkdir(mount_tmp, 0700) < 0) {
+                r = log_error_errno(errno, "Failed to create temporary mount: %m");
+                goto finish;
+        }
+
+        mount_tmp_created = true;
+
+        if (mount(args[2], mount_tmp, NULL, MS_BIND, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to overmount: %m");
+                goto finish;
+        }
+
+        mount_tmp_mounted = true;
+
+        /* Third, we remount the new bind mount read-only if requested. */
+        if (arg_read_only)
+                if (mount(NULL, mount_tmp, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) {
+                        r = log_error_errno(errno, "Failed to mark read-only: %m");
+                        goto finish;
+                }
+
+        /* Fourth, we move the new bind mount into the propagation
+         * directory. This way it will appear there read-only
+         * right-away. */
+
+        mount_outside = strappenda("/run/systemd/nspawn/propagate/", args[1], "/XXXXXX");
+        if (!mkdtemp(mount_outside)) {
+                r = log_error_errno(errno, "Cannot create propagation directory: %m");
+                goto finish;
+        }
+
+        mount_outside_created = true;
+
+        if (mount(mount_tmp, mount_outside, NULL, MS_MOVE, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to move: %m");
+                goto finish;
+        }
+
+        mount_outside_mounted = true;
+        mount_tmp_mounted = false;
+
+        (void) rmdir(mount_tmp);
+        mount_tmp_created = false;
+
+        (void) umount(mount_slave);
+        mount_slave_mounted = false;
+
+        (void) rmdir(mount_slave);
+        mount_slave_created = false;
+
+        child = fork();
+        if (child < 0) {
+                r = log_error_errno(errno, "Failed to fork(): %m");
+                goto finish;
+        }
+
+        if (child == 0) {
+                const char *mount_inside;
+                int mntfd;
+                const char *q;
+
+                q = procfs_file_alloca(leader, "ns/mnt");
+                mntfd = open(q, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+                if (mntfd < 0) {
+                        log_error_errno(errno, "Failed to open mount namespace of leader: %m");
+                        _exit(EXIT_FAILURE);
+                }
+
+                if (setns(mntfd, CLONE_NEWNS) < 0) {
+                        log_error_errno(errno, "Failed to join namespace of leader: %m");
+                        _exit(EXIT_FAILURE);
+                }
+
+                if (arg_mkdir)
+                        mkdir_p(dest, 0755);
+
+                /* Fifth, move the mount to the right place inside */
+                mount_inside = strappenda("/run/systemd/nspawn/incoming/", basename(mount_outside));
+                if (mount(mount_inside, dest, NULL, MS_MOVE, NULL) < 0) {
+                        log_error_errno(errno, "Failed to mount: %m");
+                        _exit(EXIT_FAILURE);
+                }
+
+                _exit(EXIT_SUCCESS);
+        }
+
+        r = wait_for_terminate(child, &si);
+        if (r < 0) {
+                log_error_errno(r, "Failed to wait for client: %m");
+                goto finish;
+        }
+        if (si.si_code != CLD_EXITED) {
+                log_error("Client died abnormally.");
+                r = -EIO;
+                goto finish;
+        }
+        if (si.si_status != EXIT_SUCCESS) {
+                r = -EIO;
+                goto finish;
+        }
+
+        r = 0;
+
+finish:
+        if (mount_outside_mounted)
+                umount(mount_outside);
+        if (mount_outside_created)
+                rmdir(mount_outside);
+
+        if (mount_tmp_mounted)
+                umount(mount_tmp);
+        if (mount_tmp_created)
+                umount(mount_tmp);
+
+        if (mount_slave_mounted)
+                umount(mount_slave);
+        if (mount_slave_created)
+                umount(mount_slave);
+
+        return r;
+}
+
 static int openpt_in_namespace(pid_t pid, int flags) {
-        _cleanup_close_pipe_ int pair[2] = { -1, -1 };
+        _cleanup_close_pair_ int pair[2] = { -1, -1 };
         _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, rootfd = -1;
         union {
                 struct cmsghdr cmsghdr;
@@ -427,7 +828,7 @@ static int openpt_in_namespace(pid_t pid, int flags) {
         pid_t child;
         siginfo_t si;
 
-        r = namespace_open(pid, &pidnsfd, &mntnsfd, &rootfd);
+        r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &rootfd);
         if (r < 0)
                 return r;
 
@@ -441,7 +842,7 @@ static int openpt_in_namespace(pid_t pid, int flags) {
         if (child == 0) {
                 pair[0] = safe_close(pair[0]);
 
-                r = namespace_enter(pidnsfd, mntnsfd, rootfd);
+                r = namespace_enter(pidnsfd, mntnsfd, -1, rootfd);
                 if (r < 0)
                         _exit(EXIT_FAILURE);
 
@@ -466,10 +867,10 @@ static int openpt_in_namespace(pid_t pid, int flags) {
         pair[1] = safe_close(pair[1]);
 
         r = wait_for_terminate(child, &si);
-        if (r < 0 || si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS) {
-
-                return r < 0 ? r : -EIO;
-        }
+        if (r < 0)
+                return r;
+        if (si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS)
+                return -EIO;
 
         if (recvmsg(pair[0], &mh, MSG_NOSIGNAL|MSG_CMSG_CLOEXEC) < 0)
                 return -errno;
@@ -497,15 +898,17 @@ static int openpt_in_namespace(pid_t pid, int flags) {
 }
 
 static int login_machine(sd_bus *bus, char **args, unsigned n) {
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL, *reply2 = NULL, *reply3 = NULL;
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_unref_ sd_bus *container_bus = NULL;
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_bus_close_unref_ sd_bus *container_bus = NULL;
+        _cleanup_(pty_forward_freep) PTYForward *forward = NULL;
+        _cleanup_event_unref_ sd_event *event = NULL;
         _cleanup_close_ int master = -1;
         _cleanup_free_ char *getty = NULL;
-        const char *path, *pty, *p;
-        uint32_t leader;
+        const char *pty, *p;
+        pid_t leader;
         sigset_t mask;
-        int r;
+        int r, ret = 0;
 
         assert(bus);
         assert(args);
@@ -515,53 +918,25 @@ static int login_machine(sd_bus *bus, char **args, unsigned n) {
                 return -ENOTSUP;
         }
 
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.machine1",
-                        "/org/freedesktop/machine1",
-                        "org.freedesktop.machine1.Manager",
-                        "GetMachine",
-                        &error,
-                        &reply,
-                        "s", args[1]);
-        if (r < 0) {
-                log_error("Could not get path to machine: %s", bus_error_message(&error, -r));
-                return r;
-        }
-
-        r = sd_bus_message_read(reply, "o", &path);
+        r = sd_event_default(&event);
         if (r < 0)
-                return bus_log_parse_error(r);
+                return log_error_errno(r, "Failed to get event loop: %m");
 
-        r = sd_bus_get_property(
-                        bus,
-                        "org.freedesktop.machine1",
-                        path,
-                        "org.freedesktop.machine1.Machine",
-                        "Leader",
-                        &error,
-                        &reply2,
-                        "u");
-        if (r < 0) {
-                log_error("Failed to retrieve PID of leader: %s", strerror(-r));
-                return r;
-        }
+        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 = sd_bus_message_read(reply2, "u", &leader);
+        r = machine_get_leader(bus, args[1], &leader);
         if (r < 0)
-                return bus_log_parse_error(r);
+                return r;
 
         master = openpt_in_namespace(leader, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY);
-        if (master < 0) {
-                log_error("Failed to acquire pseudo tty: %s", strerror(-master));
-                return master;
-        }
+        if (master < 0)
+                return log_error_errno(master, "Failed to acquire pseudo tty: %m");
 
         pty = ptsname(master);
-        if (!pty) {
-                log_error("Failed to get pty name: %m");
-                return -errno;
-        }
+        if (!pty)
+                return log_error_errno(errno, "Failed to get pty name: %m");
 
         p = startswith(pty, "/dev/pts/");
         if (!p) {
@@ -570,26 +945,22 @@ static int login_machine(sd_bus *bus, char **args, unsigned n) {
         }
 
         r = sd_bus_open_system_container(&container_bus, args[1]);
-        if (r < 0) {
-                log_error("Failed to get container bus: %s", strerror(-r));
-                return r;
-        }
+        if (r < 0)
+                return log_error_errno(r, "Failed to get container bus: %m");
 
         getty = strjoin("container-getty@", p, ".service", NULL);
         if (!getty)
                 return log_oom();
 
-        if (unlockpt(master) < 0) {
-                log_error("Failed to unlock tty: %m");
-                return -errno;
-        }
+        if (unlockpt(master) < 0)
+                return log_error_errno(errno, "Failed to unlock tty: %m");
 
         r = sd_bus_call_method(container_bus,
                                "org.freedesktop.systemd1",
                                "/org/freedesktop/systemd1",
                                "org.freedesktop.systemd1.Manager",
                                "StartUnit",
-                               &error, &reply3,
+                               &error, &reply,
                                "ss", getty, "replace");
         if (r < 0) {
                 log_error("Failed to start getty service: %s", bus_error_message(&error, r));
@@ -604,21 +975,28 @@ static int login_machine(sd_bus *bus, char **args, unsigned n) {
 
         log_info("Connected to container %s. Press ^] three times within 1s to exit session.", args[1]);
 
-        r = process_pty(master, &mask, 0, 0);
-        if (r < 0) {
-                log_error("Failed to process pseudo tty: %s", strerror(-r));
-                return r;
-        }
+        sd_event_add_signal(event, NULL, SIGINT, NULL, NULL);
+        sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL);
+
+        r = pty_forward_new(event, master, &forward);
+        if (r < 0)
+                return log_error_errno(r, "Failed to create PTY forwarder: %m");
+
+        r = sd_event_loop(event);
+        if (r < 0)
+                return log_error_errno(r, "Failed to run event loop: %m");
+
+        forward = pty_forward_free(forward);
 
         fputc('\n', stdout);
 
         log_info("Connection to container %s terminated.", args[1]);
 
-        return 0;
+        sd_event_get_exit_code(event, &ret);
+        return ret;
 }
 
-static int help(void) {
-
+static void help(void) {
         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
                "Send control commands to or query the virtual machine and container registration manager.\n\n"
                "  -h --help              Show this help\n"
@@ -631,7 +1009,9 @@ static int help(void) {
                "  -a --all               Show all properties, including empty ones\n"
                "  -l --full              Do not ellipsize output\n"
                "     --kill-who=WHO      Who to send signal to\n"
-               "  -s --signal=SIGNAL     Which signal to send\n\n"
+               "  -s --signal=SIGNAL     Which signal to send\n"
+               "     --read-only         Create read-only bind mount\n"
+               "     --mkdir             Create directory before bind mounting, if missing\n\n"
                "Commands:\n"
                "  list                   List running VMs and containers\n"
                "  status NAME...         Show VM/container status\n"
@@ -640,10 +1020,9 @@ static int help(void) {
                "  poweroff NAME...       Power off one or more containers\n"
                "  reboot NAME...         Reboot one or more containers\n"
                "  kill NAME...           Send signal to processes of a VM/container\n"
-               "  terminate NAME...      Terminate one or more VMs/containers\n",
+               "  terminate NAME...      Terminate one or more VMs/containers\n"
+               "  bind NAME PATH [PATH]  Bind mount a path from the host into a container\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
 static int parse_argv(int argc, char *argv[]) {
@@ -653,6 +1032,8 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_NO_PAGER,
                 ARG_NO_LEGEND,
                 ARG_KILL_WHO,
+                ARG_READ_ONLY,
+                ARG_MKDIR,
         };
 
         static const struct option options[] = {
@@ -667,6 +1048,8 @@ static int parse_argv(int argc, char *argv[]) {
                 { "signal",          required_argument, NULL, 's'                 },
                 { "host",            required_argument, NULL, 'H'                 },
                 { "machine",         required_argument, NULL, 'M'                 },
+                { "read-only",       no_argument,       NULL, ARG_READ_ONLY       },
+                { "mkdir",           no_argument,       NULL, ARG_MKDIR           },
                 {}
         };
 
@@ -675,12 +1058,13 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "hp:als:H:M:", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "hp:als:H:M:", options, NULL)) >= 0)
 
                 switch (c) {
 
                 case 'h':
-                        return help();
+                        help();
+                        return 0;
 
                 case ARG_VERSION:
                         puts(PACKAGE_STRING);
@@ -736,13 +1120,20 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_host = optarg;
                         break;
 
+                case ARG_READ_ONLY:
+                        arg_read_only = true;
+                        break;
+
+                case ARG_MKDIR:
+                        arg_mkdir = true;
+                        break;
+
                 case '?':
                         return -EINVAL;
 
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         return 1;
 }
@@ -767,6 +1158,7 @@ static int machinectl_main(sd_bus *bus, int argc, char *argv[]) {
                 { "poweroff",              MORE,   2, poweroff_machine  },
                 { "kill",                  MORE,   2, kill_machine      },
                 { "login",                 MORE,   2, login_machine     },
+                { "bind",                  MORE,   3, bind_mount        },
         };
 
         int left;
@@ -830,7 +1222,7 @@ static int machinectl_main(sd_bus *bus, int argc, char *argv[]) {
 }
 
 int main(int argc, char*argv[]) {
-        _cleanup_bus_unref_ sd_bus *bus = NULL;
+        _cleanup_bus_close_unref_ sd_bus *bus = NULL;
         int r;
 
         setlocale(LC_ALL, "");
@@ -843,7 +1235,7 @@ int main(int argc, char*argv[]) {
 
         r = bus_open_transport(arg_transport, arg_host, false, &bus);
         if (r < 0) {
-                log_error("Failed to create bus connection: %s", strerror(-r));
+                log_error_errno(r, "Failed to create bus connection: %m");
                 goto finish;
         }