Merge pull request #1191 from poettering/nspawn-split

nspawn: split up nspawn.c into multiple smaller .c files

17 files changed, 2576 insertions, 2170 deletions

diff --git a/Makefile.am b/Makefile.am
index 1a844acc13..1dfa0c0677 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2778,9 +2778,20 @@ systemd_cgtop_LDADD = \
 # ------------------------------------------------------------------------------
 systemd_nspawn_SOURCES = \
 	src/nspawn/nspawn.c \
-	src/nspawn/nspawn.h \
 	src/nspawn/nspawn-settings.c \
 	src/nspawn/nspawn-settings.h \
+	src/nspawn/nspawn-mount.c \
+	src/nspawn/nspawn-mount.h \
+	src/nspawn/nspawn-network.c \
+	src/nspawn/nspawn-network.h \
+	src/nspawn/nspawn-expose-ports.c \
+	src/nspawn/nspawn-expose-ports.h \
+	src/nspawn/nspawn-cgroup.c \
+	src/nspawn/nspawn-cgroup.h \
+	src/nspawn/nspawn-register.c \
+	src/nspawn/nspawn-register.h \
+	src/nspawn/nspawn-setuid.c \
+	src/nspawn/nspawn-setuid.h \
 	src/core/mount-setup.c \
 	src/core/mount-setup.h \
 	src/core/loopback-setup.c \
diff --git a/src/nspawn/nspawn-cgroup.c b/src/nspawn/nspawn-cgroup.c
new file mode 100644
index 0000000000..c0e9ccd7a4
--- /dev/null
+++ b/src/nspawn/nspawn-cgroup.c
@@ -0,0 +1,162 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/mount.h>
+
+#include "util.h"
+#include "strv.h"
+#include "mkdir.h"
+#include "fileio.h"
+#include "cgroup-util.h"
+
+#include "nspawn-cgroup.h"
+
+int chown_cgroup(pid_t pid, uid_t uid_shift) {
+        _cleanup_free_ char *path = NULL, *fs = NULL;
+        _cleanup_close_ int fd = -1;
+        const char *fn;
+        int r;
+
+        r = cg_pid_get_path(NULL, pid, &path);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get container cgroup path: %m");
+
+        r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, NULL, &fs);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get file system path for container cgroup: %m");
+
+        fd = open(fs, O_RDONLY|O_CLOEXEC|O_DIRECTORY);
+        if (fd < 0)
+                return log_error_errno(errno, "Failed to open %s: %m", fs);
+
+        FOREACH_STRING(fn,
+                       ".",
+                       "tasks",
+                       "notify_on_release",
+                       "cgroup.procs",
+                       "cgroup.clone_children",
+                       "cgroup.controllers",
+                       "cgroup.subtree_control",
+                       "cgroup.populated")
+                if (fchownat(fd, fn, uid_shift, uid_shift, 0) < 0)
+                        log_full_errno(errno == ENOENT ? LOG_DEBUG :  LOG_WARNING, errno,
+                                       "Failed to chown() cgroup file %s, ignoring: %m", fn);
+
+        return 0;
+}
+
+int sync_cgroup(pid_t pid, bool unified_requested) {
+        _cleanup_free_ char *cgroup = NULL;
+        char tree[] = "/tmp/unifiedXXXXXX", pid_string[DECIMAL_STR_MAX(pid) + 1];
+        bool undo_mount = false;
+        const char *fn;
+        int unified, r;
+
+        unified = cg_unified();
+        if (unified < 0)
+                return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m");
+
+        if ((unified > 0) == unified_requested)
+                return 0;
+
+        /* When the host uses the legacy cgroup setup, but the
+         * container shall use the unified hierarchy, let's make sure
+         * we copy the path from the name=systemd hierarchy into the
+         * unified hierarchy. Similar for the reverse situation. */
+
+        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get control group of " PID_FMT ": %m", pid);
+
+        /* In order to access the unified hierarchy we need to mount it */
+        if (!mkdtemp(tree))
+                return log_error_errno(errno, "Failed to generate temporary mount point for unified hierarchy: %m");
+
+        if (unified)
+                r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "none,name=systemd,xattr");
+        else
+                r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior");
+        if (r < 0) {
+                r = log_error_errno(errno, "Failed to mount unified hierarchy: %m");
+                goto finish;
+        }
+
+        undo_mount = true;
+
+        fn = strjoina(tree, cgroup, "/cgroup.procs");
+        (void) mkdir_parents(fn, 0755);
+
+        sprintf(pid_string, PID_FMT, pid);
+        r = write_string_file(fn, pid_string, 0);
+        if (r < 0)
+                log_error_errno(r, "Failed to move process: %m");
+
+finish:
+        if (undo_mount)
+                (void) umount(tree);
+
+        (void) rmdir(tree);
+        return r;
+}
+
+int create_subcgroup(pid_t pid, bool unified_requested) {
+        _cleanup_free_ char *cgroup = NULL;
+        const char *child;
+        int unified, r;
+        CGroupMask supported;
+
+        /* In the unified hierarchy inner nodes may only only contain
+         * subgroups, but not processes. Hence, if we running in the
+         * unified hierarchy and the container does the same, and we
+         * did not create a scope unit for the container move us and
+         * the container into two separate subcgroups. */
+
+        if (!unified_requested)
+                return 0;
+
+        unified = cg_unified();
+        if (unified < 0)
+                return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m");
+        if (unified == 0)
+                return 0;
+
+        r = cg_mask_supported(&supported);
+        if (r < 0)
+                return log_error_errno(r, "Failed to determine supported controllers: %m");
+
+        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get our control group: %m");
+
+        child = strjoina(cgroup, "/payload");
+        r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, pid);
+        if (r < 0)
+                return log_error_errno(r, "Failed to create %s subcgroup: %m", child);
+
+        child = strjoina(cgroup, "/supervisor");
+        r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to create %s subcgroup: %m", child);
+
+        /* Try to enable as many controllers as possible for the new payload. */
+        (void) cg_enable_everywhere(supported, supported, cgroup);
+        return 0;
+}
diff --git a/src/nspawn/nspawn-cgroup.h b/src/nspawn/nspawn-cgroup.h
new file mode 100644
index 0000000000..985fdfaad5
--- /dev/null
+++ b/src/nspawn/nspawn-cgroup.h
@@ -0,0 +1,29 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+#include <stdbool.h>
+
+int chown_cgroup(pid_t pid, uid_t uid_shift);
+int sync_cgroup(pid_t pid, bool unified_requested);
+int create_subcgroup(pid_t pid, bool unified_requested);
diff --git a/src/nspawn/nspawn-expose-ports.c b/src/nspawn/nspawn-expose-ports.c
new file mode 100644
index 0000000000..38250b6e02
--- /dev/null
+++ b/src/nspawn/nspawn-expose-ports.c
@@ -0,0 +1,277 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-netlink.h"
+
+#include "util.h"
+#include "in-addr-util.h"
+#include "firewall-util.h"
+#include "local-addresses.h"
+#include "netlink-util.h"
+
+#include "nspawn-expose-ports.h"
+
+int expose_port_parse(ExposePort **l, const char *s) {
+
+        const char *split, *e;
+        uint16_t container_port, host_port;
+        int protocol;
+        ExposePort *p;
+        int r;
+
+        assert(l);
+        assert(s);
+
+        if ((e = startswith(s, "tcp:")))
+                protocol = IPPROTO_TCP;
+        else if ((e = startswith(s, "udp:")))
+                protocol = IPPROTO_UDP;
+        else {
+                e = s;
+                protocol = IPPROTO_TCP;
+        }
+
+        split = strchr(e, ':');
+        if (split) {
+                char v[split - e + 1];
+
+                memcpy(v, e, split - e);
+                v[split - e] = 0;
+
+                r = safe_atou16(v, &host_port);
+                if (r < 0 || host_port <= 0)
+                        return -EINVAL;
+
+                r = safe_atou16(split + 1, &container_port);
+        } else {
+                r = safe_atou16(e, &container_port);
+                host_port = container_port;
+        }
+
+        if (r < 0 || container_port <= 0)
+                return -EINVAL;
+
+        LIST_FOREACH(ports, p, *l)
+                if (p->protocol == protocol && p->host_port == host_port)
+                        return -EEXIST;
+
+        p = new(ExposePort, 1);
+        if (!p)
+                return -ENOMEM;
+
+        p->protocol = protocol;
+        p->host_port = host_port;
+        p->container_port = container_port;
+
+        LIST_PREPEND(ports, *l, p);
+
+        return 0;
+}
+
+void expose_port_free_all(ExposePort *p) {
+
+        while (p) {
+                ExposePort *q = p;
+                LIST_REMOVE(ports, p, q);
+                free(q);
+        }
+}
+
+int expose_port_flush(ExposePort* l, union in_addr_union *exposed) {
+        ExposePort *p;
+        int r, af = AF_INET;
+
+        assert(exposed);
+
+        if (!l)
+                return 0;
+
+        if (in_addr_is_null(af, exposed))
+                return 0;
+
+        log_debug("Lost IP address.");
+
+        LIST_FOREACH(ports, p, l) {
+                r = fw_add_local_dnat(false,
+                                      af,
+                                      p->protocol,
+                                      NULL,
+                                      NULL, 0,
+                                      NULL, 0,
+                                      p->host_port,
+                                      exposed,
+                                      p->container_port,
+                                      NULL);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to modify firewall: %m");
+        }
+
+        *exposed = IN_ADDR_NULL;
+        return 0;
+}
+
+int expose_port_execute(sd_netlink *rtnl, ExposePort *l, union in_addr_union *exposed) {
+        _cleanup_free_ struct local_address *addresses = NULL;
+        _cleanup_free_ char *pretty = NULL;
+        union in_addr_union new_exposed;
+        ExposePort *p;
+        bool add;
+        int af = AF_INET, r;
+
+        assert(exposed);
+
+        /* Invoked each time an address is added or removed inside the
+         * container */
+
+        if (!l)
+                return 0;
+
+        r = local_addresses(rtnl, 0, af, &addresses);
+        if (r < 0)
+                return log_error_errno(r, "Failed to enumerate local addresses: %m");
+
+        add = r > 0 &&
+                addresses[0].family == af &&
+                addresses[0].scope < RT_SCOPE_LINK;
+
+        if (!add)
+                return expose_port_flush(l, exposed);
+
+        new_exposed = addresses[0].address;
+        if (in_addr_equal(af, exposed, &new_exposed))
+                return 0;
+
+        in_addr_to_string(af, &new_exposed, &pretty);
+        log_debug("New container IP is %s.", strna(pretty));
+
+        LIST_FOREACH(ports, p, l) {
+
+                r = fw_add_local_dnat(true,
+                                      af,
+                                      p->protocol,
+                                      NULL,
+                                      NULL, 0,
+                                      NULL, 0,
+                                      p->host_port,
+                                      &new_exposed,
+                                      p->container_port,
+                                      in_addr_is_null(af, exposed) ? NULL : exposed);
+                if (r < 0)
+                        log_warning_errno(r, "Failed to modify firewall: %m");
+        }
+
+        *exposed = new_exposed;
+        return 0;
+}
+
+int expose_port_send_rtnl(int send_fd) {
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_SPACE(sizeof(int))];
+        } control = {};
+        struct msghdr mh = {
+                .msg_control = &control,
+                .msg_controllen = sizeof(control),
+        };
+        struct cmsghdr *cmsg;
+        _cleanup_close_ int fd = -1;
+        ssize_t k;
+
+        assert(send_fd >= 0);
+
+        fd = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_ROUTE);
+        if (fd < 0)
+                return log_error_errno(errno, "Failed to allocate container netlink: %m");
+
+        cmsg = CMSG_FIRSTHDR(&mh);
+        cmsg->cmsg_level = SOL_SOCKET;
+        cmsg->cmsg_type = SCM_RIGHTS;
+        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
+        memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
+
+        mh.msg_controllen = cmsg->cmsg_len;
+
+        /* Store away the fd in the socket, so that it stays open as
+         * long as we run the child */
+        k = sendmsg(send_fd, &mh, MSG_NOSIGNAL);
+        if (k < 0)
+                return log_error_errno(errno, "Failed to send netlink fd: %m");
+
+        return 0;
+}
+
+int expose_port_watch_rtnl(
+                sd_event *event,
+                int recv_fd,
+                sd_netlink_message_handler_t handler,
+                union in_addr_union *exposed,
+                sd_netlink **ret) {
+
+        union {
+                struct cmsghdr cmsghdr;
+                uint8_t buf[CMSG_SPACE(sizeof(int))];
+        } control = {};
+        struct msghdr mh = {
+                .msg_control = &control,
+                .msg_controllen = sizeof(control),
+        };
+        struct cmsghdr *cmsg;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        int fd, r;
+        ssize_t k;
+
+        assert(event);
+        assert(recv_fd >= 0);
+        assert(ret);
+
+        k = recvmsg(recv_fd, &mh, MSG_NOSIGNAL);
+        if (k < 0)
+                return log_error_errno(errno, "Failed to recv netlink fd: %m");
+
+        cmsg = CMSG_FIRSTHDR(&mh);
+        assert(cmsg->cmsg_level == SOL_SOCKET);
+        assert(cmsg->cmsg_type == SCM_RIGHTS);
+        assert(cmsg->cmsg_len == CMSG_LEN(sizeof(int)));
+        memcpy(&fd, CMSG_DATA(cmsg), sizeof(int));
+
+        r = sd_netlink_open_fd(&rtnl, fd);
+        if (r < 0) {
+                safe_close(fd);
+                return log_error_errno(r, "Failed to create rtnl object: %m");
+        }
+
+        r = sd_netlink_add_match(rtnl, RTM_NEWADDR, handler, exposed);
+        if (r < 0)
+                return log_error_errno(r, "Failed to subscribe to RTM_NEWADDR messages: %m");
+
+        r = sd_netlink_add_match(rtnl, RTM_DELADDR, handler, exposed);
+        if (r < 0)
+                return log_error_errno(r, "Failed to subscribe to RTM_DELADDR messages: %m");
+
+        r = sd_netlink_attach_event(rtnl, event, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add to even loop: %m");
+
+        *ret = rtnl;
+        rtnl = NULL;
+
+        return 0;
+}
diff --git a/src/nspawn/nspawn-expose-ports.h b/src/nspawn/nspawn-expose-ports.h
new file mode 100644
index 0000000000..39cec28695
--- /dev/null
+++ b/src/nspawn/nspawn-expose-ports.h
@@ -0,0 +1,45 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <inttypes.h>
+
+#include "sd-event.h"
+#include "sd-netlink.h"
+#include "list.h"
+#include "in-addr-util.h"
+
+typedef struct ExposePort {
+        int protocol;
+        uint16_t host_port;
+        uint16_t container_port;
+        LIST_FIELDS(struct ExposePort, ports);
+} ExposePort;
+
+void expose_port_free_all(ExposePort *p);
+int expose_port_parse(ExposePort **l, const char *s);
+
+int expose_port_watch_rtnl(sd_event *event, int recv_fd, sd_netlink_message_handler_t handler, union in_addr_union *exposed, sd_netlink **ret);
+int expose_port_send_rtnl(int send_fd);
+
+int expose_port_execute(sd_netlink *rtnl, ExposePort *l, union in_addr_union *exposed);
+int expose_port_flush(ExposePort* l, union in_addr_union *exposed);
diff --git a/src/nspawn/nspawn-gperf.gperf b/src/nspawn/nspawn-gperf.gperf
index 8b68dfa9f5..074b380306 100644
--- a/src/nspawn/nspawn-gperf.gperf
+++ b/src/nspawn/nspawn-gperf.gperf
@@ -1,8 +1,8 @@
 %{
 #include <stddef.h>
 #include "conf-parser.h"
-#include "nspawn.h"
 #include "nspawn-settings.h"
+#include "nspawn-expose-ports.h"
 %}
 struct ConfigPerfItem;
 %null_strings
diff --git a/src/nspawn/nspawn-mount.c b/src/nspawn/nspawn-mount.c
new file mode 100644
index 0000000000..2bca39f45d
--- /dev/null
+++ b/src/nspawn/nspawn-mount.c
@@ -0,0 +1,869 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/mount.h>
+
+#include "util.h"
+#include "rm-rf.h"
+#include "strv.h"
+#include "path-util.h"
+#include "mkdir.h"
+#include "label.h"
+#include "set.h"
+#include "cgroup-util.h"
+
+#include "nspawn-mount.h"
+
+CustomMount* custom_mount_add(CustomMount **l, unsigned *n, CustomMountType t) {
+        CustomMount *c, *ret;
+
+        assert(l);
+        assert(n);
+        assert(t >= 0);
+        assert(t < _CUSTOM_MOUNT_TYPE_MAX);
+
+        c = realloc(*l, (*n + 1) * sizeof(CustomMount));
+        if (!c)
+                return NULL;
+
+        *l = c;
+        ret = *l + *n;
+        (*n)++;
+
+        *ret = (CustomMount) { .type = t };
+
+        return ret;
+}
+
+void custom_mount_free_all(CustomMount *l, unsigned n) {
+        unsigned i;
+
+        for (i = 0; i < n; i++) {
+                CustomMount *m = l + i;
+
+                free(m->source);
+                free(m->destination);
+                free(m->options);
+
+                if (m->work_dir) {
+                        (void) rm_rf(m->work_dir, REMOVE_ROOT|REMOVE_PHYSICAL);
+                        free(m->work_dir);
+                }
+
+                strv_free(m->lower);
+        }
+
+        free(l);
+}
+
+int custom_mount_compare(const void *a, const void *b) {
+        const CustomMount *x = a, *y = b;
+        int r;
+
+        r = path_compare(x->destination, y->destination);
+        if (r != 0)
+                return r;
+
+        if (x->type < y->type)
+                return -1;
+        if (x->type > y->type)
+                return 1;
+
+        return 0;
+}
+
+int bind_mount_parse(CustomMount **l, unsigned *n, const char *s, bool read_only) {
+        _cleanup_free_ char *source = NULL, *destination = NULL, *opts = NULL;
+        const char *p = s;
+        CustomMount *m;
+        int r;
+
+        assert(l);
+        assert(n);
+
+        r = extract_many_words(&p, ":", EXTRACT_DONT_COALESCE_SEPARATORS, &source, &destination, NULL);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        if (r == 1) {
+                destination = strdup(source);
+                if (!destination)
+                        return -ENOMEM;
+        }
+
+        if (r == 2 && !isempty(p)) {
+                opts = strdup(p);
+                if (!opts)
+                        return -ENOMEM;
+        }
+
+        if (!path_is_absolute(source))
+                return -EINVAL;
+
+        if (!path_is_absolute(destination))
+                return -EINVAL;
+
+        m = custom_mount_add(l, n, CUSTOM_MOUNT_BIND);
+        if (!m)
+                return log_oom();
+
+        m->source = source;
+        m->destination = destination;
+        m->read_only = read_only;
+        m->options = opts;
+
+        source = destination = opts = NULL;
+        return 0;
+}
+
+int tmpfs_mount_parse(CustomMount **l, unsigned *n, const char *s) {
+        _cleanup_free_ char *path = NULL, *opts = NULL;
+        const char *p = s;
+        CustomMount *m;
+        int r;
+
+        assert(l);
+        assert(n);
+        assert(s);
+
+        r = extract_first_word(&p, &path, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        if (isempty(p))
+                opts = strdup("mode=0755");
+        else
+                opts = strdup(p);
+        if (!opts)
+                return -ENOMEM;
+
+        if (!path_is_absolute(path))
+                return -EINVAL;
+
+        m = custom_mount_add(l, n, CUSTOM_MOUNT_TMPFS);
+        if (!m)
+                return -ENOMEM;
+
+        m->destination = path;
+        m->options = opts;
+
+        path = opts = NULL;
+        return 0;
+}
+
+static int tmpfs_patch_options(
+                const char *options,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context,
+                char **ret) {
+
+        char *buf = NULL;
+
+        if (userns && uid_shift != 0) {
+                assert(uid_shift != UID_INVALID);
+
+                if (options)
+                        (void) asprintf(&buf, "%s,uid=" UID_FMT ",gid=" UID_FMT, options, uid_shift, uid_shift);
+                else
+                        (void) asprintf(&buf, "uid=" UID_FMT ",gid=" UID_FMT, uid_shift, uid_shift);
+                if (!buf)
+                        return -ENOMEM;
+
+                options = buf;
+        }
+
+#ifdef HAVE_SELINUX
+        if (selinux_apifs_context) {
+                char *t;
+
+                if (options)
+                        t = strjoin(options, ",context=\"", selinux_apifs_context, "\"", NULL);
+                else
+                        t = strjoin("context=\"", selinux_apifs_context, "\"", NULL);
+                if (!t) {
+                        free(buf);
+                        return -ENOMEM;
+                }
+
+                free(buf);
+                buf = t;
+        }
+#endif
+
+        *ret = buf;
+        return !!buf;
+}
+
+int mount_all(const char *dest,
+              bool userns, uid_t uid_shift, uid_t uid_range,
+              const char *selinux_apifs_context) {
+
+        typedef struct MountPoint {
+                const char *what;
+                const char *where;
+                const char *type;
+                const char *options;
+                unsigned long flags;
+                bool fatal;
+                bool userns;
+        } MountPoint;
+
+        static const MountPoint mount_table[] = {
+                { "proc",      "/proc",          "proc",   NULL,        MS_NOSUID|MS_NOEXEC|MS_NODEV,                              true,  true  },
+                { "/proc/sys", "/proc/sys",      NULL,     NULL,        MS_BIND,                                                   true,  true  },   /* Bind mount first */
+                { NULL,        "/proc/sys",      NULL,     NULL,        MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, true,  true  },   /* Then, make it r/o */
+                { "sysfs",     "/sys",           "sysfs",  NULL,        MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV,                    true,  false },
+                { "tmpfs",     "/dev",           "tmpfs",  "mode=755",  MS_NOSUID|MS_STRICTATIME,                                  true,  false },
+                { "tmpfs",     "/dev/shm",       "tmpfs",  "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME,                         true,  false },
+                { "tmpfs",     "/run",           "tmpfs",  "mode=755",  MS_NOSUID|MS_NODEV|MS_STRICTATIME,                         true,  false },
+                { "tmpfs",     "/tmp",           "tmpfs",  "mode=1777", MS_STRICTATIME,                                            true,  false },
+#ifdef HAVE_SELINUX
+                { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL,     MS_BIND,                                                   false, false },  /* Bind mount first */
+                { NULL,              "/sys/fs/selinux", NULL, NULL,     MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, false, false },  /* Then, make it r/o */
+#endif
+        };
+
+        unsigned k;
+        int r;
+
+        for (k = 0; k < ELEMENTSOF(mount_table); k++) {
+                _cleanup_free_ char *where = NULL, *options = NULL;
+                const char *o;
+
+                if (userns != mount_table[k].userns)
+                        continue;
+
+                where = prefix_root(dest, mount_table[k].where);
+                if (!where)
+                        return log_oom();
+
+                r = path_is_mount_point(where, AT_SYMLINK_FOLLOW);
+                if (r < 0 && r != -ENOENT)
+                        return log_error_errno(r, "Failed to detect whether %s is a mount point: %m", where);
+
+                /* Skip this entry if it is not a remount. */
+                if (mount_table[k].what && r > 0)
+                        continue;
+
+                r = mkdir_p(where, 0755);
+                if (r < 0) {
+                        if (mount_table[k].fatal)
+                                return log_error_errno(r, "Failed to create directory %s: %m", where);
+
+                        log_warning_errno(r, "Failed to create directory %s: %m", where);
+                        continue;
+                }
+
+                o = mount_table[k].options;
+                if (streq_ptr(mount_table[k].type, "tmpfs")) {
+                        r = tmpfs_patch_options(o, userns, uid_shift, uid_range, selinux_apifs_context, &options);
+                        if (r < 0)
+                                return log_oom();
+                        if (r > 0)
+                                o = options;
+                }
+
+                if (mount(mount_table[k].what,
+                          where,
+                          mount_table[k].type,
+                          mount_table[k].flags,
+                          o) < 0) {
+
+                        if (mount_table[k].fatal)
+                                return log_error_errno(errno, "mount(%s) failed: %m", where);
+
+                        log_warning_errno(errno, "mount(%s) failed, ignoring: %m", where);
+                }
+        }
+
+        return 0;
+}
+
+static int parse_mount_bind_options(const char *options, unsigned long *mount_flags, char **mount_opts) {
+        const char *p = options;
+        unsigned long flags = *mount_flags;
+        char *opts = NULL;
+
+        assert(options);
+
+        for (;;) {
+                _cleanup_free_ char *word = NULL;
+                int r = extract_first_word(&p, &word, ",", 0);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to extract mount option: %m");
+                if (r == 0)
+                        break;
+
+                if (streq(word, "rbind"))
+                        flags |= MS_REC;
+                else if (streq(word, "norbind"))
+                        flags &= ~MS_REC;
+                else {
+                        log_error("Invalid bind mount option: %s", word);
+                        return -EINVAL;
+                }
+        }
+
+        *mount_flags = flags;
+        /* in the future mount_opts will hold string options for mount(2) */
+        *mount_opts = opts;
+
+        return 0;
+}
+
+static int mount_bind(const char *dest, CustomMount *m) {
+        struct stat source_st, dest_st;
+        const char *where;
+        unsigned long mount_flags = MS_BIND | MS_REC;
+        _cleanup_free_ char *mount_opts = NULL;
+        int r;
+
+        assert(m);
+
+        if (m->options) {
+                r = parse_mount_bind_options(m->options, &mount_flags, &mount_opts);
+                if (r < 0)
+                        return r;
+        }
+
+        if (stat(m->source, &source_st) < 0)
+                return log_error_errno(errno, "Failed to stat %s: %m", m->source);
+
+        where = prefix_roota(dest, m->destination);
+
+        if (stat(where, &dest_st) >= 0) {
+                if (S_ISDIR(source_st.st_mode) && !S_ISDIR(dest_st.st_mode)) {
+                        log_error("Cannot bind mount directory %s on file %s.", m->source, where);
+                        return -EINVAL;
+                }
+
+                if (!S_ISDIR(source_st.st_mode) && S_ISDIR(dest_st.st_mode)) {
+                        log_error("Cannot bind mount file %s on directory %s.", m->source, where);
+                        return -EINVAL;
+                }
+
+        } else if (errno == ENOENT) {
+                r = mkdir_parents_label(where, 0755);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to make parents of %s: %m", where);
+        } else {
+                log_error_errno(errno, "Failed to stat %s: %m", where);
+                return -errno;
+        }
+
+        /* Create the mount point. Any non-directory file can be
+         * mounted on any non-directory file (regular, fifo, socket,
+         * char, block).
+         */
+        if (S_ISDIR(source_st.st_mode))
+                r = mkdir_label(where, 0755);
+        else
+                r = touch(where);
+        if (r < 0 && r != -EEXIST)
+                return log_error_errno(r, "Failed to create mount point %s: %m", where);
+
+        if (mount(m->source, where, NULL, mount_flags, mount_opts) < 0)
+                return log_error_errno(errno, "mount(%s) failed: %m", where);
+
+        if (m->read_only) {
+                r = bind_remount_recursive(where, true);
+                if (r < 0)
+                        return log_error_errno(r, "Read-only bind mount failed: %m");
+        }
+
+        return 0;
+}
+
+static int mount_tmpfs(
+                const char *dest,
+                CustomMount *m,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        const char *where, *options;
+        _cleanup_free_ char *buf = NULL;
+        int r;
+
+        assert(dest);
+        assert(m);
+
+        where = prefix_roota(dest, m->destination);
+
+        r = mkdir_p_label(where, 0755);
+        if (r < 0 && r != -EEXIST)
+                return log_error_errno(r, "Creating mount point for tmpfs %s failed: %m", where);
+
+        r = tmpfs_patch_options(m->options, userns, uid_shift, uid_range, selinux_apifs_context, &buf);
+        if (r < 0)
+                return log_oom();
+        options = r > 0 ? buf : m->options;
+
+        if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, options) < 0)
+                return log_error_errno(errno, "tmpfs mount to %s failed: %m", where);
+
+        return 0;
+}
+
+static char *joined_and_escaped_lower_dirs(char * const *lower) {
+        _cleanup_strv_free_ char **sv = NULL;
+
+        sv = strv_copy(lower);
+        if (!sv)
+                return NULL;
+
+        strv_reverse(sv);
+
+        if (!strv_shell_escape(sv, ",:"))
+                return NULL;
+
+        return strv_join(sv, ":");
+}
+
+static int mount_overlay(const char *dest, CustomMount *m) {
+        _cleanup_free_ char *lower = NULL;
+        const char *where, *options;
+        int r;
+
+        assert(dest);
+        assert(m);
+
+        where = prefix_roota(dest, m->destination);
+
+        r = mkdir_label(where, 0755);
+        if (r < 0 && r != -EEXIST)
+                return log_error_errno(r, "Creating mount point for overlay %s failed: %m", where);
+
+        (void) mkdir_p_label(m->source, 0755);
+
+        lower = joined_and_escaped_lower_dirs(m->lower);
+        if (!lower)
+                return log_oom();
+
+        if (m->read_only) {
+                _cleanup_free_ char *escaped_source = NULL;
+
+                escaped_source = shell_escape(m->source, ",:");
+                if (!escaped_source)
+                        return log_oom();
+
+                options = strjoina("lowerdir=", escaped_source, ":", lower);
+        } else {
+                _cleanup_free_ char *escaped_source = NULL, *escaped_work_dir = NULL;
+
+                assert(m->work_dir);
+                (void) mkdir_label(m->work_dir, 0700);
+
+                escaped_source = shell_escape(m->source, ",:");
+                if (!escaped_source)
+                        return log_oom();
+                escaped_work_dir = shell_escape(m->work_dir, ",:");
+                if (!escaped_work_dir)
+                        return log_oom();
+
+                options = strjoina("lowerdir=", lower, ",upperdir=", escaped_source, ",workdir=", escaped_work_dir);
+        }
+
+        if (mount("overlay", where, "overlay", m->read_only ? MS_RDONLY : 0, options) < 0)
+                return log_error_errno(errno, "overlay mount to %s failed: %m", where);
+
+        return 0;
+}
+
+int mount_custom(
+                const char *dest,
+                CustomMount *mounts, unsigned n,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        unsigned i;
+        int r;
+
+        assert(dest);
+
+        for (i = 0; i < n; i++) {
+                CustomMount *m = mounts + i;
+
+                switch (m->type) {
+
+                case CUSTOM_MOUNT_BIND:
+                        r = mount_bind(dest, m);
+                        break;
+
+                case CUSTOM_MOUNT_TMPFS:
+                        r = mount_tmpfs(dest, m, userns, uid_shift, uid_range, selinux_apifs_context);
+                        break;
+
+                case CUSTOM_MOUNT_OVERLAY:
+                        r = mount_overlay(dest, m);
+                        break;
+
+                default:
+                        assert_not_reached("Unknown custom mount type");
+                }
+
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+static int mount_legacy_cgroup_hierarchy(const char *dest, const char *controller, const char *hierarchy, bool read_only) {
+        char *to;
+        int r;
+
+        to = strjoina(dest, "/sys/fs/cgroup/", hierarchy);
+
+        r = path_is_mount_point(to, 0);
+        if (r < 0 && r != -ENOENT)
+                return log_error_errno(r, "Failed to determine if %s is mounted already: %m", to);
+        if (r > 0)
+                return 0;
+
+        mkdir_p(to, 0755);
+
+        /* The superblock mount options of the mount point need to be
+         * identical to the hosts', and hence writable... */
+        if (mount("cgroup", to, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, controller) < 0)
+                return log_error_errno(errno, "Failed to mount to %s: %m", to);
+
+        /* ... hence let's only make the bind mount read-only, not the
+         * superblock. */
+        if (read_only) {
+                if (mount(NULL, to, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0)
+                        return log_error_errno(errno, "Failed to remount %s read-only: %m", to);
+        }
+        return 1;
+}
+
+static int mount_legacy_cgroups(
+                const char *dest,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        _cleanup_set_free_free_ Set *controllers = NULL;
+        const char *cgroup_root;
+        int r;
+
+        cgroup_root = prefix_roota(dest, "/sys/fs/cgroup");
+
+        /* Mount a tmpfs to /sys/fs/cgroup if it's not mounted there yet. */
+        r = path_is_mount_point(cgroup_root, AT_SYMLINK_FOLLOW);
+        if (r < 0)
+                return log_error_errno(r, "Failed to determine if /sys/fs/cgroup is already mounted: %m");
+        if (r == 0) {
+                _cleanup_free_ char *options = NULL;
+
+                r = tmpfs_patch_options("mode=755", userns, uid_shift, uid_range, selinux_apifs_context, &options);
+                if (r < 0)
+                        return log_oom();
+
+                if (mount("tmpfs", cgroup_root, "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, options) < 0)
+                        return log_error_errno(errno, "Failed to mount /sys/fs/cgroup: %m");
+        }
+
+        if (cg_unified() > 0)
+                goto skip_controllers;
+
+        controllers = set_new(&string_hash_ops);
+        if (!controllers)
+                return log_oom();
+
+        r = cg_kernel_controllers(controllers);
+        if (r < 0)
+                return log_error_errno(r, "Failed to determine cgroup controllers: %m");
+
+        for (;;) {
+                _cleanup_free_ char *controller = NULL, *origin = NULL, *combined = NULL;
+
+                controller = set_steal_first(controllers);
+                if (!controller)
+                        break;
+
+                origin = prefix_root("/sys/fs/cgroup/", controller);
+                if (!origin)
+                        return log_oom();
+
+                r = readlink_malloc(origin, &combined);
+                if (r == -EINVAL) {
+                        /* Not a symbolic link, but directly a single cgroup hierarchy */
+
+                        r = mount_legacy_cgroup_hierarchy(dest, controller, controller, true);
+                        if (r < 0)
+                                return r;
+
+                } else if (r < 0)
+                        return log_error_errno(r, "Failed to read link %s: %m", origin);
+                else {
+                        _cleanup_free_ char *target = NULL;
+
+                        target = prefix_root(dest, origin);
+                        if (!target)
+                                return log_oom();
+
+                        /* A symbolic link, a combination of controllers in one hierarchy */
+
+                        if (!filename_is_valid(combined)) {
+                                log_warning("Ignoring invalid combined hierarchy %s.", combined);
+                                continue;
+                        }
+
+                        r = mount_legacy_cgroup_hierarchy(dest, combined, combined, true);
+                        if (r < 0)
+                                return r;
+
+                        r = symlink_idempotent(combined, target);
+                        if (r == -EINVAL) {
+                                log_error("Invalid existing symlink for combined hierarchy");
+                                return r;
+                        }
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to create symlink for combined hierarchy: %m");
+                }
+        }
+
+skip_controllers:
+        r = mount_legacy_cgroup_hierarchy(dest, "none,name=systemd,xattr", "systemd", false);
+        if (r < 0)
+                return r;
+
+        if (mount(NULL, cgroup_root, NULL, MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME|MS_RDONLY, "mode=755") < 0)
+                return log_error_errno(errno, "Failed to remount %s read-only: %m", cgroup_root);
+
+        return 0;
+}
+
+static int mount_unified_cgroups(const char *dest) {
+        const char *p;
+        int r;
+
+        assert(dest);
+
+        p = strjoina(dest, "/sys/fs/cgroup");
+
+        r = path_is_mount_point(p, AT_SYMLINK_FOLLOW);
+        if (r < 0)
+                return log_error_errno(r, "Failed to determine if %s is mounted already: %m", p);
+        if (r > 0) {
+                p = strjoina(dest, "/sys/fs/cgroup/cgroup.procs");
+                if (access(p, F_OK) >= 0)
+                        return 0;
+                if (errno != ENOENT)
+                        return log_error_errno(errno, "Failed to determine if mount point %s contains the unified cgroup hierarchy: %m", p);
+
+                log_error("%s is already mounted but not a unified cgroup hierarchy. Refusing.", p);
+                return -EINVAL;
+        }
+
+        if (mount("cgroup", p, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior") < 0)
+                return log_error_errno(errno, "Failed to mount unified cgroup hierarchy to %s: %m", p);
+
+        return 0;
+}
+
+int mount_cgroups(
+                const char *dest,
+                bool unified_requested,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        if (unified_requested)
+                return mount_unified_cgroups(dest);
+        else
+                return mount_legacy_cgroups(dest, userns, uid_shift, uid_range, selinux_apifs_context);
+}
+
+int mount_systemd_cgroup_writable(
+                const char *dest,
+                bool unified_requested) {
+
+        _cleanup_free_ char *own_cgroup_path = NULL;
+        const char *systemd_root, *systemd_own;
+        int r;
+
+        assert(dest);
+
+        r = cg_pid_get_path(NULL, 0, &own_cgroup_path);
+        if (r < 0)
+                return log_error_errno(r, "Failed to determine our own cgroup path: %m");
+
+        /* If we are living in the top-level, then there's nothing to do... */
+        if (path_equal(own_cgroup_path, "/"))
+                return 0;
+
+        if (unified_requested) {
+                systemd_own = strjoina(dest, "/sys/fs/cgroup", own_cgroup_path);
+                systemd_root = prefix_roota(dest, "/sys/fs/cgroup");
+        } else {
+                systemd_own = strjoina(dest, "/sys/fs/cgroup/systemd", own_cgroup_path);
+                systemd_root = prefix_roota(dest, "/sys/fs/cgroup/systemd");
+        }
+
+        /* Make our own cgroup a (writable) bind mount */
+        if (mount(systemd_own, systemd_own,  NULL, MS_BIND, NULL) < 0)
+                return log_error_errno(errno, "Failed to turn %s into a bind mount: %m", own_cgroup_path);
+
+        /* And then remount the systemd cgroup root read-only */
+        if (mount(NULL, systemd_root, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0)
+                return log_error_errno(errno, "Failed to mount cgroup root read-only: %m");
+
+        return 0;
+}
+
+int setup_volatile_state(
+                const char *directory,
+                VolatileMode mode,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        _cleanup_free_ char *buf = NULL;
+        const char *p, *options;
+        int r;
+
+        assert(directory);
+
+        if (mode != VOLATILE_STATE)
+                return 0;
+
+        /* --volatile=state means we simply overmount /var
+           with a tmpfs, and the rest read-only. */
+
+        r = bind_remount_recursive(directory, true);
+        if (r < 0)
+                return log_error_errno(r, "Failed to remount %s read-only: %m", directory);
+
+        p = prefix_roota(directory, "/var");
+        r = mkdir(p, 0755);
+        if (r < 0 && errno != EEXIST)
+                return log_error_errno(errno, "Failed to create %s: %m", directory);
+
+        options = "mode=755";
+        r = tmpfs_patch_options(options, userns, uid_shift, uid_range, selinux_apifs_context, &buf);
+        if (r < 0)
+                return log_oom();
+        if (r > 0)
+                options = buf;
+
+        if (mount("tmpfs", p, "tmpfs", MS_STRICTATIME, options) < 0)
+                return log_error_errno(errno, "Failed to mount tmpfs to /var: %m");
+
+        return 0;
+}
+
+int setup_volatile(
+                const char *directory,
+                VolatileMode mode,
+                bool userns, uid_t uid_shift, uid_t uid_range,
+                const char *selinux_apifs_context) {
+
+        bool tmpfs_mounted = false, bind_mounted = false;
+        char template[] = "/tmp/nspawn-volatile-XXXXXX";
+        _cleanup_free_ char *buf = NULL;
+        const char *f, *t, *options;
+        int r;
+
+        assert(directory);
+
+        if (mode != VOLATILE_YES)
+                return 0;
+
+        /* --volatile=yes means we mount a tmpfs to the root dir, and
+           the original /usr to use inside it, and that read-only. */
+
+        if (!mkdtemp(template))
+                return log_error_errno(errno, "Failed to create temporary directory: %m");
+
+        options = "mode=755";
+        r = tmpfs_patch_options(options, userns, uid_shift, uid_range, selinux_apifs_context, &buf);
+        if (r < 0)
+                return log_oom();
+        if (r > 0)
+                options = buf;
+
+        if (mount("tmpfs", template, "tmpfs", MS_STRICTATIME, options) < 0) {
+                r = log_error_errno(errno, "Failed to mount tmpfs for root directory: %m");
+                goto fail;
+        }
+
+        tmpfs_mounted = true;
+
+        f = prefix_roota(directory, "/usr");
+        t = prefix_roota(template, "/usr");
+
+        r = mkdir(t, 0755);
+        if (r < 0 && errno != EEXIST) {
+                r = log_error_errno(errno, "Failed to create %s: %m", t);
+                goto fail;
+        }
+
+        if (mount(f, t, NULL, MS_BIND|MS_REC, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to create /usr bind mount: %m");
+                goto fail;
+        }
+
+        bind_mounted = true;
+
+        r = bind_remount_recursive(t, true);
+        if (r < 0) {
+                log_error_errno(r, "Failed to remount %s read-only: %m", t);
+                goto fail;
+        }
+
+        if (mount(template, directory, NULL, MS_MOVE, NULL) < 0) {
+                r = log_error_errno(errno, "Failed to move root mount: %m");
+                goto fail;
+        }
+
+        (void) rmdir(template);
+
+        return 0;
+
+fail:
+        if (bind_mounted)
+                (void) umount(t);
+
+        if (tmpfs_mounted)
+                (void) umount(template);
+        (void) rmdir(template);
+        return r;
+}
+
+VolatileMode volatile_mode_from_string(const char *s) {
+        int b;
+
+        if (isempty(s))
+                return _VOLATILE_MODE_INVALID;
+
+        b = parse_boolean(s);
+        if (b > 0)
+                return VOLATILE_YES;
+        if (b == 0)
+                return VOLATILE_NO;
+
+        if (streq(s, "state"))
+                return VOLATILE_STATE;
+
+        return _VOLATILE_MODE_INVALID;
+}
diff --git a/src/nspawn/nspawn.h b/src/nspawn/nspawn-mount.h
index 2124b434fe..5abd44cc4b 100644
--- a/src/nspawn/nspawn.h
+++ b/src/nspawn/nspawn-mount.h
@@ -21,11 +21,8 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <inttypes.h>
 #include <stdbool.h>
 
-#include "list.h"
-
 typedef enum VolatileMode {
         VOLATILE_NO,
         VOLATILE_YES,
@@ -52,18 +49,22 @@ typedef struct CustomMount {
         char **lower;
 } CustomMount;
 
-typedef struct ExposePort {
-        int protocol;
-        uint16_t host_port;
-        uint16_t container_port;
-        LIST_FIELDS(struct ExposePort, ports);
-} ExposePort;
+CustomMount* custom_mount_add(CustomMount **l, unsigned *n, CustomMountType t);
 
 void custom_mount_free_all(CustomMount *l, unsigned n);
 int bind_mount_parse(CustomMount **l, unsigned *n, const char *s, bool read_only);
 int tmpfs_mount_parse(CustomMount **l, unsigned *n, const char *s);
 
-void expose_port_free_all(ExposePort *p);
-int expose_port_parse(ExposePort **l, const char *s);
+int custom_mount_compare(const void *a, const void *b);
+
+int mount_all(const char *dest, bool userns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context);
+
+int mount_cgroups(const char *dest, bool unified_requested, bool userns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context);
+int mount_systemd_cgroup_writable(const char *dest, bool unified_requested);
+
+int mount_custom(const char *dest, CustomMount *mounts, unsigned n, bool userns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context);
+
+int setup_volatile(const char *directory, VolatileMode mode, bool userns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context);
+int setup_volatile_state(const char *directory, VolatileMode mode, bool userns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context);
 
 VolatileMode volatile_mode_from_string(const char *s);
diff --git a/src/nspawn/nspawn-network.c b/src/nspawn/nspawn-network.c
new file mode 100644
index 0000000000..74abe5379a
--- /dev/null
+++ b/src/nspawn/nspawn-network.c
@@ -0,0 +1,440 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <linux/veth.h>
+#include <net/if.h>
+
+#include "sd-id128.h"
+#include "sd-netlink.h"
+#include "libudev.h"
+
+#include "util.h"
+#include "ether-addr-util.h"
+#include "siphash24.h"
+#include "netlink-util.h"
+#include "udev-util.h"
+
+#include "nspawn-network.h"
+
+#define HOST_HASH_KEY SD_ID128_MAKE(1a,37,6f,c7,46,ec,45,0b,ad,a3,d5,31,06,60,5d,b1)
+#define CONTAINER_HASH_KEY SD_ID128_MAKE(c3,c4,f9,19,b5,57,b2,1c,e6,cf,14,27,03,9c,ee,a2)
+#define MACVLAN_HASH_KEY SD_ID128_MAKE(00,13,6d,bc,66,83,44,81,bb,0c,f9,51,1f,24,a6,6f)
+
+static int generate_mac(
+                const char *machine_name,
+                struct ether_addr *mac,
+                sd_id128_t hash_key,
+                uint64_t idx) {
+
+        uint8_t result[8];
+        size_t l, sz;
+        uint8_t *v, *i;
+        int r;
+
+        l = strlen(machine_name);
+        sz = sizeof(sd_id128_t) + l;
+        if (idx > 0)
+                sz += sizeof(idx);
+
+        v = alloca(sz);
+
+        /* fetch some persistent data unique to the host */
+        r = sd_id128_get_machine((sd_id128_t*) v);
+        if (r < 0)
+                return r;
+
+        /* combine with some data unique (on this host) to this
+         * container instance */
+        i = mempcpy(v + sizeof(sd_id128_t), machine_name, l);
+        if (idx > 0) {
+                idx = htole64(idx);
+                memcpy(i, &idx, sizeof(idx));
+        }
+
+        /* Let's hash the host machine ID plus the container name. We
+         * use a fixed, but originally randomly created hash key here. */
+        siphash24(result, v, sz, hash_key.bytes);
+
+        assert_cc(ETH_ALEN <= sizeof(result));
+        memcpy(mac->ether_addr_octet, result, ETH_ALEN);
+
+        /* see eth_random_addr in the kernel */
+        mac->ether_addr_octet[0] &= 0xfe;        /* clear multicast bit */
+        mac->ether_addr_octet[0] |= 0x02;        /* set local assignment bit (IEEE802) */
+
+        return 0;
+}
+
+int setup_veth(const char *machine_name,
+               pid_t pid,
+               char iface_name[IFNAMSIZ],
+               bool bridge) {
+
+        _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        struct ether_addr mac_host, mac_container;
+        int r, i;
+
+        /* Use two different interface name prefixes depending whether
+         * we are in bridge mode or not. */
+        snprintf(iface_name, IFNAMSIZ - 1, "%s-%s",
+                 bridge ? "vb" : "ve", machine_name);
+
+        r = generate_mac(machine_name, &mac_container, CONTAINER_HASH_KEY, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate predictable MAC address for container side: %m");
+
+        r = generate_mac(machine_name, &mac_host, HOST_HASH_KEY, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to generate predictable MAC address for host side: %m");
+
+        r = sd_netlink_open(&rtnl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to connect to netlink: %m");
+
+        r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate netlink message: %m");
+
+        r = sd_netlink_message_append_string(m, IFLA_IFNAME, iface_name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink interface name: %m");
+
+        r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac_host);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink MAC address: %m");
+
+        r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
+        if (r < 0)
+                return log_error_errno(r, "Failed to open netlink container: %m");
+
+        r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "veth");
+        if (r < 0)
+                return log_error_errno(r, "Failed to open netlink container: %m");
+
+        r = sd_netlink_message_open_container(m, VETH_INFO_PEER);
+        if (r < 0)
+                return log_error_errno(r, "Failed to open netlink container: %m");
+
+        r = sd_netlink_message_append_string(m, IFLA_IFNAME, "host0");
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink interface name: %m");
+
+        r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac_container);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink MAC address: %m");
+
+        r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink namespace field: %m");
+
+        r = sd_netlink_message_close_container(m);
+        if (r < 0)
+                return log_error_errno(r, "Failed to close netlink container: %m");
+
+        r = sd_netlink_message_close_container(m);
+        if (r < 0)
+                return log_error_errno(r, "Failed to close netlink container: %m");
+
+        r = sd_netlink_message_close_container(m);
+        if (r < 0)
+                return log_error_errno(r, "Failed to close netlink container: %m");
+
+        r = sd_netlink_call(rtnl, m, 0, NULL);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add new veth interfaces (host0, %s): %m", iface_name);
+
+        i = (int) if_nametoindex(iface_name);
+        if (i <= 0)
+                return log_error_errno(errno, "Failed to resolve interface %s: %m", iface_name);
+
+        return i;
+}
+
+int setup_bridge(const char *veth_name, const char *bridge_name) {
+        _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        int r, bridge_ifi;
+
+        assert(veth_name);
+        assert(bridge_name);
+
+        bridge_ifi = (int) if_nametoindex(bridge_name);
+        if (bridge_ifi <= 0)
+                return log_error_errno(errno, "Failed to resolve interface %s: %m", bridge_name);
+
+        r = sd_netlink_open(&rtnl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to connect to netlink: %m");
+
+        r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0);
+        if (r < 0)
+                return log_error_errno(r, "Failed to allocate netlink message: %m");
+
+        r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP);
+        if (r < 0)
+                return log_error_errno(r, "Failed to set IFF_UP flag: %m");
+
+        r = sd_netlink_message_append_string(m, IFLA_IFNAME, veth_name);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink interface name field: %m");
+
+        r = sd_netlink_message_append_u32(m, IFLA_MASTER, bridge_ifi);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add netlink master field: %m");
+
+        r = sd_netlink_call(rtnl, m, 0, NULL);
+        if (r < 0)
+                return log_error_errno(r, "Failed to add veth interface to bridge: %m");
+
+        return bridge_ifi;
+}
+
+static int parse_interface(struct udev *udev, const char *name) {
+        _cleanup_udev_device_unref_ struct udev_device *d = NULL;
+        char ifi_str[2 + DECIMAL_STR_MAX(int)];
+        int ifi;
+
+        ifi = (int) if_nametoindex(name);
+        if (ifi <= 0)
+                return log_error_errno(errno, "Failed to resolve interface %s: %m", name);
+
+        sprintf(ifi_str, "n%i", ifi);
+        d = udev_device_new_from_device_id(udev, ifi_str);
+        if (!d)
+                return log_error_errno(errno, "Failed to get udev device for interface %s: %m", name);
+
+        if (udev_device_get_is_initialized(d) <= 0) {
+                log_error("Network interface %s is not initialized yet.", name);
+                return -EBUSY;
+        }
+
+        return ifi;
+}
+
+int move_network_interfaces(pid_t pid, char **ifaces) {
+        _cleanup_udev_unref_ struct udev *udev = NULL;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        char **i;
+        int r;
+
+        if (strv_isempty(ifaces))
+                return 0;
+
+        r = sd_netlink_open(&rtnl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to connect to netlink: %m");
+
+        udev = udev_new();
+        if (!udev) {
+                log_error("Failed to connect to udev.");
+                return -ENOMEM;
+        }
+
+        STRV_FOREACH(i, ifaces) {
+                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
+                int ifi;
+
+                ifi = parse_interface(udev, *i);
+                if (ifi < 0)
+                        return ifi;
+
+                r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, ifi);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to allocate netlink message: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to append namespace PID to netlink message: %m");
+
+                r = sd_netlink_call(rtnl, m, 0, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to move interface %s to namespace: %m", *i);
+        }
+
+        return 0;
+}
+
+int setup_macvlan(const char *machine_name, pid_t pid, char **ifaces) {
+        _cleanup_udev_unref_ struct udev *udev = NULL;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        unsigned idx = 0;
+        char **i;
+        int r;
+
+        if (strv_isempty(ifaces))
+                return 0;
+
+        r = sd_netlink_open(&rtnl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to connect to netlink: %m");
+
+        udev = udev_new();
+        if (!udev) {
+                log_error("Failed to connect to udev.");
+                return -ENOMEM;
+        }
+
+        STRV_FOREACH(i, ifaces) {
+                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
+                _cleanup_free_ char *n = NULL;
+                struct ether_addr mac;
+                int ifi;
+
+                ifi = parse_interface(udev, *i);
+                if (ifi < 0)
+                        return ifi;
+
+                r = generate_mac(machine_name, &mac, MACVLAN_HASH_KEY, idx++);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to create MACVLAN MAC address: %m");
+
+                r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to allocate netlink message: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink interface index: %m");
+
+                n = strappend("mv-", *i);
+                if (!n)
+                        return log_oom();
+
+                strshorten(n, IFNAMSIZ-1);
+
+                r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink interface name: %m");
+
+                r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink MAC address: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink namespace field: %m");
+
+                r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to open netlink container: %m");
+
+                r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "macvlan");
+                if (r < 0)
+                        return log_error_errno(r, "Failed to open netlink container: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_MACVLAN_MODE, MACVLAN_MODE_BRIDGE);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to append macvlan mode: %m");
+
+                r = sd_netlink_message_close_container(m);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to close netlink container: %m");
+
+                r = sd_netlink_message_close_container(m);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to close netlink container: %m");
+
+                r = sd_netlink_call(rtnl, m, 0, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add new macvlan interfaces: %m");
+        }
+
+        return 0;
+}
+
+int setup_ipvlan(const char *machine_name, pid_t pid, char **ifaces) {
+        _cleanup_udev_unref_ struct udev *udev = NULL;
+        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
+        char **i;
+        int r;
+
+        if (strv_isempty(ifaces))
+                return 0;
+
+        r = sd_netlink_open(&rtnl);
+        if (r < 0)
+                return log_error_errno(r, "Failed to connect to netlink: %m");
+
+        udev = udev_new();
+        if (!udev) {
+                log_error("Failed to connect to udev.");
+                return -ENOMEM;
+        }
+
+        STRV_FOREACH(i, ifaces) {
+                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
+                _cleanup_free_ char *n = NULL;
+                int ifi;
+
+                ifi = parse_interface(udev, *i);
+                if (ifi < 0)
+                        return ifi;
+
+                r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to allocate netlink message: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink interface index: %m");
+
+                n = strappend("iv-", *i);
+                if (!n)
+                        return log_oom();
+
+                strshorten(n, IFNAMSIZ-1);
+
+                r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink interface name: %m");
+
+                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add netlink namespace field: %m");
+
+                r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to open netlink container: %m");
+
+                r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "ipvlan");
+                if (r < 0)
+                        return log_error_errno(r, "Failed to open netlink container: %m");
+
+                r = sd_netlink_message_append_u16(m, IFLA_IPVLAN_MODE, IPVLAN_MODE_L2);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add ipvlan mode: %m");
+
+                r = sd_netlink_message_close_container(m);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to close netlink container: %m");
+
+                r = sd_netlink_message_close_container(m);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to close netlink container: %m");
+
+                r = sd_netlink_call(rtnl, m, 0, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to add new ipvlan interfaces: %m");
+        }
+
+        return 0;
+}
diff --git a/src/nspawn/nspawn-network.h b/src/nspawn/nspawn-network.h
new file mode 100644
index 0000000000..311e6d06cb
--- /dev/null
+++ b/src/nspawn/nspawn-network.h
@@ -0,0 +1,36 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <net/if.h>
+
+#include <sys/types.h>
+#include <stdbool.h>
+
+int setup_veth(const char *machine_name, pid_t pid, char iface_name[IFNAMSIZ], bool bridge);
+
+int setup_bridge(const char *veth_name, const char *bridge_name);
+
+int setup_macvlan(const char *machine_name, pid_t pid, char **ifaces);
+int setup_ipvlan(const char *machine_name, pid_t pid, char **ifaces);
+
+int move_network_interfaces(pid_t pid, char **ifaces);
diff --git a/src/nspawn/nspawn-register.c b/src/nspawn/nspawn-register.c
new file mode 100644
index 0000000000..b2776a61c2
--- /dev/null
+++ b/src/nspawn/nspawn-register.c
@@ -0,0 +1,244 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-bus.h"
+
+#include "util.h"
+#include "strv.h"
+#include "bus-util.h"
+#include "bus-error.h"
+
+#include "nspawn-register.h"
+
+int register_machine(
+                const char *machine_name,
+                pid_t pid,
+                const char *directory,
+                sd_id128_t uuid,
+                int local_ifindex,
+                const char *slice,
+                CustomMount *mounts,
+                unsigned n_mounts,
+                int kill_signal,
+                char **properties,
+                bool keep_unit) {
+
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
+        int r;
+
+        r = sd_bus_default_system(&bus);
+        if (r < 0)
+                return log_error_errno(r, "Failed to open system bus: %m");
+
+        if (keep_unit) {
+                r = sd_bus_call_method(
+                                bus,
+                                "org.freedesktop.machine1",
+                                "/org/freedesktop/machine1",
+                                "org.freedesktop.machine1.Manager",
+                                "RegisterMachineWithNetwork",
+                                &error,
+                                NULL,
+                                "sayssusai",
+                                machine_name,
+                                SD_BUS_MESSAGE_APPEND_ID128(uuid),
+                                "nspawn",
+                                "container",
+                                (uint32_t) pid,
+                                strempty(directory),
+                                local_ifindex > 0 ? 1 : 0, local_ifindex);
+        } else {
+                _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
+                char **i;
+                unsigned j;
+
+                r = sd_bus_message_new_method_call(
+                                bus,
+                                &m,
+                                "org.freedesktop.machine1",
+                                "/org/freedesktop/machine1",
+                                "org.freedesktop.machine1.Manager",
+                                "CreateMachineWithNetwork");
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                r = sd_bus_message_append(
+                                m,
+                                "sayssusai",
+                                machine_name,
+                                SD_BUS_MESSAGE_APPEND_ID128(uuid),
+                                "nspawn",
+                                "container",
+                                (uint32_t) pid,
+                                strempty(directory),
+                                local_ifindex > 0 ? 1 : 0, local_ifindex);
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                r = sd_bus_message_open_container(m, 'a', "(sv)");
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                if (!isempty(slice)) {
+                        r = sd_bus_message_append(m, "(sv)", "Slice", "s", slice);
+                        if (r < 0)
+                                return bus_log_create_error(r);
+                }
+
+                r = sd_bus_message_append(m, "(sv)", "DevicePolicy", "s", "strict");
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                /* If you make changes here, also make sure to update
+                 * systemd-nspawn@.service, to keep the device
+                 * policies in sync regardless if we are run with or
+                 * without the --keep-unit switch. */
+                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 9,
+                                          /* Allow the container to
+                                           * access and create the API
+                                           * device nodes, so that
+                                           * PrivateDevices= in the
+                                           * container can work
+                                           * fine */
+                                          "/dev/null", "rwm",
+                                          "/dev/zero", "rwm",
+                                          "/dev/full", "rwm",
+                                          "/dev/random", "rwm",
+                                          "/dev/urandom", "rwm",
+                                          "/dev/tty", "rwm",
+                                          "/dev/net/tun", "rwm",
+                                          /* Allow the container
+                                           * access to ptys. However,
+                                           * do not permit the
+                                           * container to ever create
+                                           * these device nodes. */
+                                          "/dev/pts/ptmx", "rw",
+                                          "char-pts", "rw");
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                for (j = 0; j < n_mounts; j++) {
+                        CustomMount *cm = mounts + j;
+
+                        if (cm->type != CUSTOM_MOUNT_BIND)
+                                continue;
+
+                        r = is_device_node(cm->source);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to stat %s: %m", cm->source);
+
+                        if (r) {
+                                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 1,
+                                        cm->source, cm->read_only ? "r" : "rw");
+                                if (r < 0)
+                                        return log_error_errno(r, "Failed to append message arguments: %m");
+                        }
+                }
+
+                if (kill_signal != 0) {
+                        r = sd_bus_message_append(m, "(sv)", "KillSignal", "i", kill_signal);
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = sd_bus_message_append(m, "(sv)", "KillMode", "s", "mixed");
+                        if (r < 0)
+                                return bus_log_create_error(r);
+                }
+
+                STRV_FOREACH(i, properties) {
+                        r = sd_bus_message_open_container(m, 'r', "sv");
+                        if (r < 0)
+                                return bus_log_create_error(r);
+
+                        r = bus_append_unit_property_assignment(m, *i);
+                        if (r < 0)
+                                return r;
+
+                        r = sd_bus_message_close_container(m);
+                        if (r < 0)
+                                return bus_log_create_error(r);
+                }
+
+                r = sd_bus_message_close_container(m);
+                if (r < 0)
+                        return bus_log_create_error(r);
+
+                r = sd_bus_call(bus, m, 0, &error, NULL);
+        }
+
+        if (r < 0) {
+                log_error("Failed to register machine: %s", bus_error_message(&error, r));
+                return r;
+        }
+
+        return 0;
+}
+
+int terminate_machine(pid_t pid) {
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
+        const char *path;
+        int r;
+
+        r = sd_bus_default_system(&bus);
+        if (r < 0)
+                return log_error_errno(r, "Failed to open system bus: %m");
+
+        r = sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.machine1",
+                        "/org/freedesktop/machine1",
+                        "org.freedesktop.machine1.Manager",
+                        "GetMachineByPID",
+                        &error,
+                        &reply,
+                        "u",
+                        (uint32_t) pid);
+        if (r < 0) {
+                /* Note that the machine might already have been
+                 * cleaned up automatically, hence don't consider it a
+                 * failure if we cannot get the machine object. */
+                log_debug("Failed to get machine: %s", bus_error_message(&error, r));
+                return 0;
+        }
+
+        r = sd_bus_message_read(reply, "o", &path);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_call_method(
+                        bus,
+                        "org.freedesktop.machine1",
+                        path,
+                        "org.freedesktop.machine1.Machine",
+                        "Terminate",
+                        &error,
+                        NULL,
+                        NULL);
+        if (r < 0) {
+                log_debug("Failed to terminate machine: %s", bus_error_message(&error, r));
+                return 0;
+        }
+
+        return 0;
+}
diff --git a/src/nspawn/nspawn-register.h b/src/nspawn/nspawn-register.h
new file mode 100644
index 0000000000..b27841ff59
--- /dev/null
+++ b/src/nspawn/nspawn-register.h
@@ -0,0 +1,31 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+
+#include "sd-id128.h"
+
+#include "nspawn-mount.h"
+
+int register_machine(const char *machine_name, pid_t pid, const char *directory, sd_id128_t uuid, int local_ifindex, const char *slice, CustomMount *mounts, unsigned n_mounts, int kill_signal, char **properties, bool keep_unit);
+int terminate_machine(pid_t pid);
diff --git a/src/nspawn/nspawn-settings.c b/src/nspawn/nspawn-settings.c
index 9a403a3068..419f5d1c40 100644
--- a/src/nspawn/nspawn-settings.c
+++ b/src/nspawn/nspawn-settings.c
@@ -24,7 +24,6 @@
 #include "strv.h"
 #include "cap-list.h"
 
-#include "nspawn.h"
 #include "nspawn-settings.h"
 
 int settings_load(FILE *f, const char *path, Settings **ret) {
diff --git a/src/nspawn/nspawn-settings.h b/src/nspawn/nspawn-settings.h
index d9b3b2f7c0..4cec40c1b7 100644
--- a/src/nspawn/nspawn-settings.h
+++ b/src/nspawn/nspawn-settings.h
@@ -24,7 +24,9 @@
 #include <stdio.h>
 
 #include "macro.h"
-#include "nspawn.h"
+
+#include "nspawn-mount.h"
+#include "nspawn-expose-ports.h"
 
 typedef enum SettingsMask {
         SETTING_BOOT          = 1 << 0,
diff --git a/src/nspawn/nspawn-setuid.c b/src/nspawn/nspawn-setuid.c
new file mode 100644
index 0000000000..eda7f62900
--- /dev/null
+++ b/src/nspawn/nspawn-setuid.c
@@ -0,0 +1,272 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <grp.h>
+
+#include "util.h"
+#include "signal-util.h"
+#include "mkdir.h"
+#include "process-util.h"
+
+#include "nspawn-setuid.h"
+
+static int spawn_getent(const char *database, const char *key, pid_t *rpid) {
+        int pipe_fds[2];
+        pid_t pid;
+
+        assert(database);
+        assert(key);
+        assert(rpid);
+
+        if (pipe2(pipe_fds, O_CLOEXEC) < 0)
+                return log_error_errno(errno, "Failed to allocate pipe: %m");
+
+        pid = fork();
+        if (pid < 0)
+                return log_error_errno(errno, "Failed to fork getent child: %m");
+        else if (pid == 0) {
+                int nullfd;
+                char *empty_env = NULL;
+
+                if (dup3(pipe_fds[1], STDOUT_FILENO, 0) < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (pipe_fds[0] > 2)
+                        safe_close(pipe_fds[0]);
+                if (pipe_fds[1] > 2)
+                        safe_close(pipe_fds[1]);
+
+                nullfd = open("/dev/null", O_RDWR);
+                if (nullfd < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (dup3(nullfd, STDIN_FILENO, 0) < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (dup3(nullfd, STDERR_FILENO, 0) < 0)
+                        _exit(EXIT_FAILURE);
+
+                if (nullfd > 2)
+                        safe_close(nullfd);
+
+                (void) reset_all_signal_handlers();
+                (void) reset_signal_mask();
+                close_all_fds(NULL, 0);
+
+                execle("/usr/bin/getent", "getent", database, key, NULL, &empty_env);
+                execle("/bin/getent", "getent", database, key, NULL, &empty_env);
+                _exit(EXIT_FAILURE);
+        }
+
+        pipe_fds[1] = safe_close(pipe_fds[1]);
+
+        *rpid = pid;
+
+        return pipe_fds[0];
+}
+
+int change_uid_gid(const char *user, char **_home) {
+        char line[LINE_MAX], *x, *u, *g, *h;
+        const char *word, *state;
+        _cleanup_free_ uid_t *uids = NULL;
+        _cleanup_free_ char *home = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_close_ int fd = -1;
+        unsigned n_uids = 0;
+        size_t sz = 0, l;
+        uid_t uid;
+        gid_t gid;
+        pid_t pid;
+        int r;
+
+        assert(_home);
+
+        if (!user || streq(user, "root") || streq(user, "0")) {
+                /* Reset everything fully to 0, just in case */
+
+                r = reset_uid_gid();
+                if (r < 0)
+                        return log_error_errno(r, "Failed to become root: %m");
+
+                *_home = NULL;
+                return 0;
+        }
+
+        /* First, get user credentials */
+        fd = spawn_getent("passwd", user, &pid);
+        if (fd < 0)
+                return fd;
+
+        f = fdopen(fd, "r");
+        if (!f)
+                return log_oom();
+        fd = -1;
+
+        if (!fgets(line, sizeof(line), f)) {
+
+                if (!ferror(f)) {
+                        log_error("Failed to resolve user %s.", user);
+                        return -ESRCH;
+                }
+
+                log_error_errno(errno, "Failed to read from getent: %m");
+                return -errno;
+        }
+
+        truncate_nl(line);
+
+        wait_for_terminate_and_warn("getent passwd", pid, true);
+
+        x = strchr(line, ':');
+        if (!x) {
+                log_error("/etc/passwd entry has invalid user field.");
+                return -EIO;
+        }
+
+        u = strchr(x+1, ':');
+        if (!u) {
+                log_error("/etc/passwd entry has invalid password field.");
+                return -EIO;
+        }
+
+        u++;
+        g = strchr(u, ':');
+        if (!g) {
+                log_error("/etc/passwd entry has invalid UID field.");
+                return -EIO;
+        }
+
+        *g = 0;
+        g++;
+        x = strchr(g, ':');
+        if (!x) {
+                log_error("/etc/passwd entry has invalid GID field.");
+                return -EIO;
+        }
+
+        *x = 0;
+        h = strchr(x+1, ':');
+        if (!h) {
+                log_error("/etc/passwd entry has invalid GECOS field.");
+                return -EIO;
+        }
+
+        h++;
+        x = strchr(h, ':');
+        if (!x) {
+                log_error("/etc/passwd entry has invalid home directory field.");
+                return -EIO;
+        }
+
+        *x = 0;
+
+        r = parse_uid(u, &uid);
+        if (r < 0) {
+                log_error("Failed to parse UID of user.");
+                return -EIO;
+        }
+
+        r = parse_gid(g, &gid);
+        if (r < 0) {
+                log_error("Failed to parse GID of user.");
+                return -EIO;
+        }
+
+        home = strdup(h);
+        if (!home)
+                return log_oom();
+
+        /* Second, get group memberships */
+        fd = spawn_getent("initgroups", user, &pid);
+        if (fd < 0)
+                return fd;
+
+        fclose(f);
+        f = fdopen(fd, "r");
+        if (!f)
+                return log_oom();
+        fd = -1;
+
+        if (!fgets(line, sizeof(line), f)) {
+                if (!ferror(f)) {
+                        log_error("Failed to resolve user %s.", user);
+                        return -ESRCH;
+                }
+
+                log_error_errno(errno, "Failed to read from getent: %m");
+                return -errno;
+        }
+
+        truncate_nl(line);
+
+        wait_for_terminate_and_warn("getent initgroups", pid, true);
+
+        /* Skip over the username and subsequent separator whitespace */
+        x = line;
+        x += strcspn(x, WHITESPACE);
+        x += strspn(x, WHITESPACE);
+
+        FOREACH_WORD(word, l, x, state) {
+                char c[l+1];
+
+                memcpy(c, word, l);
+                c[l] = 0;
+
+                if (!GREEDY_REALLOC(uids, sz, n_uids+1))
+                        return log_oom();
+
+                r = parse_uid(c, &uids[n_uids++]);
+                if (r < 0) {
+                        log_error("Failed to parse group data from getent.");
+                        return -EIO;
+                }
+        }
+
+        r = mkdir_parents(home, 0775);
+        if (r < 0)
+                return log_error_errno(r, "Failed to make home root directory: %m");
+
+        r = mkdir_safe(home, 0755, uid, gid);
+        if (r < 0 && r != -EEXIST)
+                return log_error_errno(r, "Failed to make home directory: %m");
+
+        (void) fchown(STDIN_FILENO, uid, gid);
+        (void) fchown(STDOUT_FILENO, uid, gid);
+        (void) fchown(STDERR_FILENO, uid, gid);
+
+        if (setgroups(n_uids, uids) < 0)
+                return log_error_errno(errno, "Failed to set auxiliary groups: %m");
+
+        if (setresgid(gid, gid, gid) < 0)
+                return log_error_errno(errno, "setregid() failed: %m");
+
+        if (setresuid(uid, uid, uid) < 0)
+                return log_error_errno(errno, "setreuid() failed: %m");
+
+        if (_home) {
+                *_home = home;
+                home = NULL;
+        }
+
+        return 0;
+}
diff --git a/src/nspawn/nspawn-setuid.h b/src/nspawn/nspawn-setuid.h
new file mode 100644
index 0000000000..33be44a946
--- /dev/null
+++ b/src/nspawn/nspawn-setuid.h
@@ -0,0 +1,24 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+int change_uid_gid(const char *user, char **ret);
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c
index a8afcd1466..ff8539397f 100644
--- a/src/nspawn/nspawn.c
+++ b/src/nspawn/nspawn.c
@@ -19,91 +19,78 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <signal.h>
-#include <sched.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/mount.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
+#ifdef HAVE_BLKID
+#include <blkid/blkid.h>
+#endif
 #include <errno.h>
-#include <sys/prctl.h>
 #include <getopt.h>
-#include <grp.h>
-#include <linux/fs.h>
-#include <sys/socket.h>
-#include <linux/netlink.h>
-#include <net/if.h>
-#include <linux/veth.h>
-#include <sys/personality.h>
 #include <linux/loop.h>
-#include <sys/file.h>
-
-#ifdef HAVE_SELINUX
-#include <selinux/selinux.h>
-#endif
-
+#include <sched.h>
 #ifdef HAVE_SECCOMP
 #include <seccomp.h>
 #endif
-
-#ifdef HAVE_BLKID
-#include <blkid/blkid.h>
+#ifdef HAVE_SELINUX
+#include <selinux/selinux.h>
 #endif
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/file.h>
+#include <sys/mount.h>
+#include <sys/personality.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <unistd.h>
 
 #include "sd-daemon.h"
-#include "sd-bus.h"
 #include "sd-id128.h"
-#include "sd-netlink.h"
-#include "random-util.h"
-#include "log.h"
-#include "util.h"
-#include "mkdir.h"
-#include "rm-rf.h"
-#include "macro.h"
-#include "missing.h"
+
+#include "barrier.h"
+#include "base-filesystem.h"
+#include "blkid-util.h"
+#include "btrfs-util.h"
+#include "build.h"
+#include "cap-list.h"
+#include "capability.h"
 #include "cgroup-util.h"
-#include "strv.h"
-#include "path-util.h"
-#include "loopback-setup.h"
+#include "copy.h"
 #include "dev-setup.h"
+#include "env-util.h"
+#include "event-util.h"
 #include "fdset.h"
-#include "build.h"
 #include "fileio.h"
-#include "bus-util.h"
-#include "bus-error.h"
-#include "ptyfwd.h"
-#include "env-util.h"
-#include "netlink-util.h"
-#include "udev-util.h"
-#include "blkid-util.h"
+#include "formats-util.h"
 #include "gpt.h"
-#include "siphash24.h"
-#include "copy.h"
-#include "base-filesystem.h"
-#include "barrier.h"
-#include "event-util.h"
-#include "capability.h"
-#include "cap-list.h"
-#include "btrfs-util.h"
+#include "hostname-util.h"
+#include "log.h"
+#include "loopback-setup.h"
 #include "machine-image.h"
-#include "list.h"
-#include "in-addr-util.h"
-#include "firewall-util.h"
-#include "local-addresses.h"
-#include "formats-util.h"
+#include "macro.h"
+#include "missing.h"
+#include "mkdir.h"
+#include "netlink-util.h"
+#include "path-util.h"
 #include "process-util.h"
-#include "terminal-util.h"
-#include "hostname-util.h"
-#include "signal-util.h"
-
+#include "ptyfwd.h"
+#include "random-util.h"
+#include "rm-rf.h"
 #ifdef HAVE_SECCOMP
 #include "seccomp-util.h"
 #endif
+#include "signal-util.h"
+#include "strv.h"
+#include "terminal-util.h"
+#include "udev-util.h"
+#include "util.h"
 
-#include "nspawn.h"
 #include "nspawn-settings.h"
+#include "nspawn-mount.h"
+#include "nspawn-network.h"
+#include "nspawn-expose-ports.h"
+#include "nspawn-cgroup.h"
+#include "nspawn-register.h"
+#include "nspawn-setuid.h"
 
 typedef enum ContainerStatus {
         CONTAINER_TERMINATED,
@@ -256,63 +243,6 @@ static void help(void) {
                , program_invocation_short_name);
 }
 
-static CustomMount* custom_mount_add(CustomMount **l, unsigned *n, CustomMountType t) {
-        CustomMount *c, *ret;
-
-        assert(l);
-        assert(n);
-        assert(t >= 0);
-        assert(t < _CUSTOM_MOUNT_TYPE_MAX);
-
-        c = realloc(*l, (*n + 1) * sizeof(CustomMount));
-        if (!c)
-                return NULL;
-
-        *l = c;
-        ret = *l + *n;
-        (*n)++;
-
-        *ret = (CustomMount) { .type = t };
-
-        return ret;
-}
-
-void custom_mount_free_all(CustomMount *l, unsigned n) {
-        unsigned i;
-
-        for (i = 0; i < n; i++) {
-                CustomMount *m = l + i;
-
-                free(m->source);
-                free(m->destination);
-                free(m->options);
-
-                if (m->work_dir) {
-                        (void) rm_rf(m->work_dir, REMOVE_ROOT|REMOVE_PHYSICAL);
-                        free(m->work_dir);
-                }
-
-                strv_free(m->lower);
-        }
-
-        free(l);
-}
-
-static int custom_mount_compare(const void *a, const void *b) {
-        const CustomMount *x = a, *y = b;
-        int r;
-
-        r = path_compare(x->destination, y->destination);
-        if (r != 0)
-                return r;
-
-        if (x->type < y->type)
-                return -1;
-        if (x->type > y->type)
-                return 1;
-
-        return 0;
-}
 
 static int custom_mounts_prepare(void) {
         unsigned i;
@@ -392,161 +322,6 @@ static int detect_unified_cgroup_hierarchy(void) {
         return 0;
 }
 
-VolatileMode volatile_mode_from_string(const char *s) {
-        int b;
-
-        if (isempty(s))
-                return _VOLATILE_MODE_INVALID;
-
-        b = parse_boolean(s);
-        if (b > 0)
-                return VOLATILE_YES;
-        if (b == 0)
-                return VOLATILE_NO;
-
-        if (streq(s, "state"))
-                return VOLATILE_STATE;
-
-        return _VOLATILE_MODE_INVALID;
-}
-
-int expose_port_parse(ExposePort **l, const char *s) {
-
-        const char *split, *e;
-        uint16_t container_port, host_port;
-        int protocol;
-        ExposePort *p;
-        int r;
-
-        if ((e = startswith(s, "tcp:")))
-                protocol = IPPROTO_TCP;
-        else if ((e = startswith(s, "udp:")))
-                protocol = IPPROTO_UDP;
-        else {
-                e = s;
-                protocol = IPPROTO_TCP;
-        }
-
-        split = strchr(e, ':');
-        if (split) {
-                char v[split - e + 1];
-
-                memcpy(v, e, split - e);
-                v[split - e] = 0;
-
-                r = safe_atou16(v, &host_port);
-                if (r < 0 || host_port <= 0)
-                        return -EINVAL;
-
-                r = safe_atou16(split + 1, &container_port);
-        } else {
-                r = safe_atou16(e, &container_port);
-                host_port = container_port;
-        }
-
-        if (r < 0 || container_port <= 0)
-                return -EINVAL;
-
-        LIST_FOREACH(ports, p, arg_expose_ports)
-                if (p->protocol == protocol && p->host_port == host_port)
-                        return -EEXIST;
-
-        p = new(ExposePort, 1);
-        if (!p)
-                return -ENOMEM;
-
-        p->protocol = protocol;
-        p->host_port = host_port;
-        p->container_port = container_port;
-
-        LIST_PREPEND(ports, *l, p);
-
-        return 0;
-}
-
-int bind_mount_parse(CustomMount **l, unsigned *n, const char *s, bool read_only) {
-        _cleanup_free_ char *source = NULL, *destination = NULL, *opts = NULL;
-        const char *p = s;
-        CustomMount *m;
-        int r;
-
-        assert(l);
-        assert(n);
-
-        r = extract_many_words(&p, ":", EXTRACT_DONT_COALESCE_SEPARATORS, &source, &destination, NULL);
-        if (r < 0)
-                return r;
-        if (r == 0)
-                return -EINVAL;
-
-        if (r == 1) {
-                destination = strdup(source);
-                if (!destination)
-                        return -ENOMEM;
-        }
-
-        if (r == 2 && !isempty(p)) {
-                opts = strdup(p);
-                if (!opts)
-                        return -ENOMEM;
-        }
-
-        if (!path_is_absolute(source))
-                return -EINVAL;
-
-        if (!path_is_absolute(destination))
-                return -EINVAL;
-
-        m = custom_mount_add(l, n, CUSTOM_MOUNT_BIND);
-        if (!m)
-                return log_oom();
-
-        m->source = source;
-        m->destination = destination;
-        m->read_only = read_only;
-        m->options = opts;
-
-        source = destination = opts = NULL;
-        return 0;
-}
-
-int tmpfs_mount_parse(CustomMount **l, unsigned *n, const char *s) {
-        _cleanup_free_ char *path = NULL, *opts = NULL;
-        const char *p = s;
-        CustomMount *m;
-        int r;
-
-        assert(l);
-        assert(n);
-        assert(s);
-
-        r = extract_first_word(&p, &path, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
-        if (r < 0)
-                return r;
-        if (r == 0)
-                return -EINVAL;
-
-        if (isempty(p))
-                opts = strdup("mode=0755");
-        else
-                opts = strdup(p);
-        if (!opts)
-                return -ENOMEM;
-
-        if (!path_is_absolute(path))
-                return -EINVAL;
-
-        m = custom_mount_add(l, n, CUSTOM_MOUNT_TMPFS);
-        if (!m)
-                return -ENOMEM;
-
-        m->destination = path;
-        m->options = opts;
-
-        path = opts = NULL;
-        return 0;
-}
-
 static int parse_argv(int argc, char *argv[]) {
 
         enum {
@@ -1170,536 +945,6 @@ static int verify_arguments(void) {
         return 0;
 }
 
-static int tmpfs_patch_options(const char *options, char **ret) {
-        char *buf = NULL;
-
-        if (arg_userns && arg_uid_shift != 0) {
-                assert(arg_uid_shift != UID_INVALID);
-
-                if (options)
-                        (void) asprintf(&buf, "%s,uid=" UID_FMT ",gid=" UID_FMT, options, arg_uid_shift, arg_uid_shift);
-                else
-                        (void) asprintf(&buf, "uid=" UID_FMT ",gid=" UID_FMT, arg_uid_shift, arg_uid_shift);
-                if (!buf)
-                        return -ENOMEM;
-
-                options = buf;
-        }
-
-#ifdef HAVE_SELINUX
-        if (arg_selinux_apifs_context) {
-                char *t;
-
-                if (options)
-                        t = strjoin(options, ",context=\"", arg_selinux_apifs_context, "\"", NULL);
-                else
-                        t = strjoin("context=\"", arg_selinux_apifs_context, "\"", NULL);
-                if (!t) {
-                        free(buf);
-                        return -ENOMEM;
-                }
-
-                free(buf);
-                buf = t;
-        }
-#endif
-
-        *ret = buf;
-        return !!buf;
-}
-
-static int mount_all(const char *dest, bool userns) {
-
-        typedef struct MountPoint {
-                const char *what;
-                const char *where;
-                const char *type;
-                const char *options;
-                unsigned long flags;
-                bool fatal;
-                bool userns;
-        } MountPoint;
-
-        static const MountPoint mount_table[] = {
-                { "proc",      "/proc",          "proc",   NULL,        MS_NOSUID|MS_NOEXEC|MS_NODEV,                              true,  true  },
-                { "/proc/sys", "/proc/sys",      NULL,     NULL,        MS_BIND,                                                   true,  true  },   /* Bind mount first */
-                { NULL,        "/proc/sys",      NULL,     NULL,        MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, true,  true  },   /* Then, make it r/o */
-                { "sysfs",     "/sys",           "sysfs",  NULL,        MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV,                    true,  false },
-                { "tmpfs",     "/dev",           "tmpfs",  "mode=755",  MS_NOSUID|MS_STRICTATIME,                                  true,  false },
-                { "tmpfs",     "/dev/shm",       "tmpfs",  "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME,                         true,  false },
-                { "tmpfs",     "/run",           "tmpfs",  "mode=755",  MS_NOSUID|MS_NODEV|MS_STRICTATIME,                         true,  false },
-                { "tmpfs",     "/tmp",           "tmpfs",  "mode=1777", MS_STRICTATIME,                                            true,  false },
-#ifdef HAVE_SELINUX
-                { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL,     MS_BIND,                                                   false, false },  /* Bind mount first */
-                { NULL,              "/sys/fs/selinux", NULL, NULL,     MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, false, false },  /* Then, make it r/o */
-#endif
-        };
-
-        unsigned k;
-        int r;
-
-        for (k = 0; k < ELEMENTSOF(mount_table); k++) {
-                _cleanup_free_ char *where = NULL, *options = NULL;
-                const char *o;
-
-                if (userns != mount_table[k].userns)
-                        continue;
-
-                where = prefix_root(dest, mount_table[k].where);
-                if (!where)
-                        return log_oom();
-
-                r = path_is_mount_point(where, AT_SYMLINK_FOLLOW);
-                if (r < 0 && r != -ENOENT)
-                        return log_error_errno(r, "Failed to detect whether %s is a mount point: %m", where);
-
-                /* Skip this entry if it is not a remount. */
-                if (mount_table[k].what && r > 0)
-                        continue;
-
-                r = mkdir_p(where, 0755);
-                if (r < 0) {
-                        if (mount_table[k].fatal)
-                                return log_error_errno(r, "Failed to create directory %s: %m", where);
-
-                        log_warning_errno(r, "Failed to create directory %s: %m", where);
-                        continue;
-                }
-
-                o = mount_table[k].options;
-                if (streq_ptr(mount_table[k].type, "tmpfs")) {
-                        r = tmpfs_patch_options(o, &options);
-                        if (r < 0)
-                                return log_oom();
-                        if (r > 0)
-                                o = options;
-                }
-
-                if (mount(mount_table[k].what,
-                          where,
-                          mount_table[k].type,
-                          mount_table[k].flags,
-                          o) < 0) {
-
-                        if (mount_table[k].fatal)
-                                return log_error_errno(errno, "mount(%s) failed: %m", where);
-
-                        log_warning_errno(errno, "mount(%s) failed, ignoring: %m", where);
-                }
-        }
-
-        return 0;
-}
-
-static int parse_mount_bind_options(const char *options, unsigned long *mount_flags, char **mount_opts) {
-        const char *p = options;
-        unsigned long flags = *mount_flags;
-        char *opts = NULL;
-
-        assert(options);
-
-        for (;;) {
-                _cleanup_free_ char *word = NULL;
-                int r = extract_first_word(&p, &word, ",", 0);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to extract mount option: %m");
-                if (r == 0)
-                        break;
-
-                if (streq(word, "rbind"))
-                        flags |= MS_REC;
-                else if (streq(word, "norbind"))
-                        flags &= ~MS_REC;
-                else {
-                        log_error("Invalid bind mount option: %s", word);
-                        return -EINVAL;
-                }
-        }
-
-        *mount_flags = flags;
-        /* in the future mount_opts will hold string options for mount(2) */
-        *mount_opts = opts;
-
-        return 0;
-}
-
-static int mount_bind(const char *dest, CustomMount *m) {
-        struct stat source_st, dest_st;
-        const char *where;
-        unsigned long mount_flags = MS_BIND | MS_REC;
-        _cleanup_free_ char *mount_opts = NULL;
-        int r;
-
-        assert(m);
-
-        if (m->options) {
-                r = parse_mount_bind_options(m->options, &mount_flags, &mount_opts);
-                if (r < 0)
-                        return r;
-        }
-
-        if (stat(m->source, &source_st) < 0)
-                return log_error_errno(errno, "Failed to stat %s: %m", m->source);
-
-        where = prefix_roota(dest, m->destination);
-
-        if (stat(where, &dest_st) >= 0) {
-                if (S_ISDIR(source_st.st_mode) && !S_ISDIR(dest_st.st_mode)) {
-                        log_error("Cannot bind mount directory %s on file %s.", m->source, where);
-                        return -EINVAL;
-                }
-
-                if (!S_ISDIR(source_st.st_mode) && S_ISDIR(dest_st.st_mode)) {
-                        log_error("Cannot bind mount file %s on directory %s.", m->source, where);
-                        return -EINVAL;
-                }
-
-        } else if (errno == ENOENT) {
-                r = mkdir_parents_label(where, 0755);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to make parents of %s: %m", where);
-        } else {
-                log_error_errno(errno, "Failed to stat %s: %m", where);
-                return -errno;
-        }
-
-        /* Create the mount point. Any non-directory file can be
-         * mounted on any non-directory file (regular, fifo, socket,
-         * char, block).
-         */
-        if (S_ISDIR(source_st.st_mode))
-                r = mkdir_label(where, 0755);
-        else
-                r = touch(where);
-        if (r < 0 && r != -EEXIST)
-                return log_error_errno(r, "Failed to create mount point %s: %m", where);
-
-        if (mount(m->source, where, NULL, mount_flags, mount_opts) < 0)
-                return log_error_errno(errno, "mount(%s) failed: %m", where);
-
-        if (m->read_only) {
-                r = bind_remount_recursive(where, true);
-                if (r < 0)
-                        return log_error_errno(r, "Read-only bind mount failed: %m");
-        }
-
-        return 0;
-}
-
-static int mount_tmpfs(const char *dest, CustomMount *m) {
-        const char *where, *options;
-        _cleanup_free_ char *buf = NULL;
-        int r;
-
-        assert(dest);
-        assert(m);
-
-        where = prefix_roota(dest, m->destination);
-
-        r = mkdir_p_label(where, 0755);
-        if (r < 0 && r != -EEXIST)
-                return log_error_errno(r, "Creating mount point for tmpfs %s failed: %m", where);
-
-        r = tmpfs_patch_options(m->options, &buf);
-        if (r < 0)
-                return log_oom();
-        options = r > 0 ? buf : m->options;
-
-        if (mount("tmpfs", where, "tmpfs", MS_NODEV|MS_STRICTATIME, options) < 0)
-                return log_error_errno(errno, "tmpfs mount to %s failed: %m", where);
-
-        return 0;
-}
-
-static char *joined_and_escaped_lower_dirs(char * const *lower) {
-        _cleanup_strv_free_ char **sv = NULL;
-
-        sv = strv_copy(lower);
-        if (!sv)
-                return NULL;
-
-        strv_reverse(sv);
-
-        if (!strv_shell_escape(sv, ",:"))
-                return NULL;
-
-        return strv_join(sv, ":");
-}
-
-static int mount_overlay(const char *dest, CustomMount *m) {
-        _cleanup_free_ char *lower = NULL;
-        const char *where, *options;
-        int r;
-
-        assert(dest);
-        assert(m);
-
-        where = prefix_roota(dest, m->destination);
-
-        r = mkdir_label(where, 0755);
-        if (r < 0 && r != -EEXIST)
-                return log_error_errno(r, "Creating mount point for overlay %s failed: %m", where);
-
-        (void) mkdir_p_label(m->source, 0755);
-
-        lower = joined_and_escaped_lower_dirs(m->lower);
-        if (!lower)
-                return log_oom();
-
-        if (m->read_only) {
-                _cleanup_free_ char *escaped_source = NULL;
-
-                escaped_source = shell_escape(m->source, ",:");
-                if (!escaped_source)
-                        return log_oom();
-
-                options = strjoina("lowerdir=", escaped_source, ":", lower);
-        } else {
-                _cleanup_free_ char *escaped_source = NULL, *escaped_work_dir = NULL;
-
-                assert(m->work_dir);
-                (void) mkdir_label(m->work_dir, 0700);
-
-                escaped_source = shell_escape(m->source, ",:");
-                if (!escaped_source)
-                        return log_oom();
-                escaped_work_dir = shell_escape(m->work_dir, ",:");
-                if (!escaped_work_dir)
-                        return log_oom();
-
-                options = strjoina("lowerdir=", lower, ",upperdir=", escaped_source, ",workdir=", escaped_work_dir);
-        }
-
-        if (mount("overlay", where, "overlay", m->read_only ? MS_RDONLY : 0, options) < 0)
-                return log_error_errno(errno, "overlay mount to %s failed: %m", where);
-
-        return 0;
-}
-
-static int mount_custom(const char *dest) {
-        unsigned i;
-        int r;
-
-        assert(dest);
-
-        for (i = 0; i < arg_n_custom_mounts; i++) {
-                CustomMount *m = &arg_custom_mounts[i];
-
-                switch (m->type) {
-
-                case CUSTOM_MOUNT_BIND:
-                        r = mount_bind(dest, m);
-                        break;
-
-                case CUSTOM_MOUNT_TMPFS:
-                        r = mount_tmpfs(dest, m);
-                        break;
-
-                case CUSTOM_MOUNT_OVERLAY:
-                        r = mount_overlay(dest, m);
-                        break;
-
-                default:
-                        assert_not_reached("Unknown custom mount type");
-                }
-
-                if (r < 0)
-                        return r;
-        }
-
-        return 0;
-}
-
-static int mount_legacy_cgroup_hierarchy(const char *dest, const char *controller, const char *hierarchy, bool read_only) {
-        char *to;
-        int r;
-
-        to = strjoina(dest, "/sys/fs/cgroup/", hierarchy);
-
-        r = path_is_mount_point(to, 0);
-        if (r < 0 && r != -ENOENT)
-                return log_error_errno(r, "Failed to determine if %s is mounted already: %m", to);
-        if (r > 0)
-                return 0;
-
-        mkdir_p(to, 0755);
-
-        /* The superblock mount options of the mount point need to be
-         * identical to the hosts', and hence writable... */
-        if (mount("cgroup", to, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, controller) < 0)
-                return log_error_errno(errno, "Failed to mount to %s: %m", to);
-
-        /* ... hence let's only make the bind mount read-only, not the
-         * superblock. */
-        if (read_only) {
-                if (mount(NULL, to, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0)
-                        return log_error_errno(errno, "Failed to remount %s read-only: %m", to);
-        }
-        return 1;
-}
-
-static int mount_legacy_cgroups(const char *dest) {
-        _cleanup_set_free_free_ Set *controllers = NULL;
-        const char *cgroup_root;
-        int r;
-
-        cgroup_root = prefix_roota(dest, "/sys/fs/cgroup");
-
-        /* Mount a tmpfs to /sys/fs/cgroup if it's not mounted there yet. */
-        r = path_is_mount_point(cgroup_root, AT_SYMLINK_FOLLOW);
-        if (r < 0)
-                return log_error_errno(r, "Failed to determine if /sys/fs/cgroup is already mounted: %m");
-        if (r == 0) {
-                _cleanup_free_ char *options = NULL;
-
-                r = tmpfs_patch_options("mode=755", &options);
-                if (r < 0)
-                        return log_oom();
-
-                if (mount("tmpfs", cgroup_root, "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, options) < 0)
-                        return log_error_errno(errno, "Failed to mount /sys/fs/cgroup: %m");
-        }
-
-        if (cg_unified() > 0)
-                goto skip_controllers;
-
-        controllers = set_new(&string_hash_ops);
-        if (!controllers)
-                return log_oom();
-
-        r = cg_kernel_controllers(controllers);
-        if (r < 0)
-                return log_error_errno(r, "Failed to determine cgroup controllers: %m");
-
-        for (;;) {
-                _cleanup_free_ char *controller = NULL, *origin = NULL, *combined = NULL;
-
-                controller = set_steal_first(controllers);
-                if (!controller)
-                        break;
-
-                origin = prefix_root("/sys/fs/cgroup/", controller);
-                if (!origin)
-                        return log_oom();
-
-                r = readlink_malloc(origin, &combined);
-                if (r == -EINVAL) {
-                        /* Not a symbolic link, but directly a single cgroup hierarchy */
-
-                        r = mount_legacy_cgroup_hierarchy(dest, controller, controller, true);
-                        if (r < 0)
-                                return r;
-
-                } else if (r < 0)
-                        return log_error_errno(r, "Failed to read link %s: %m", origin);
-                else {
-                        _cleanup_free_ char *target = NULL;
-
-                        target = prefix_root(dest, origin);
-                        if (!target)
-                                return log_oom();
-
-                        /* A symbolic link, a combination of controllers in one hierarchy */
-
-                        if (!filename_is_valid(combined)) {
-                                log_warning("Ignoring invalid combined hierarchy %s.", combined);
-                                continue;
-                        }
-
-                        r = mount_legacy_cgroup_hierarchy(dest, combined, combined, true);
-                        if (r < 0)
-                                return r;
-
-                        r = symlink_idempotent(combined, target);
-                        if (r == -EINVAL) {
-                                log_error("Invalid existing symlink for combined hierarchy");
-                                return r;
-                        }
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to create symlink for combined hierarchy: %m");
-                }
-        }
-
-skip_controllers:
-        r = mount_legacy_cgroup_hierarchy(dest, "none,name=systemd,xattr", "systemd", false);
-        if (r < 0)
-                return r;
-
-        if (mount(NULL, cgroup_root, NULL, MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME|MS_RDONLY, "mode=755") < 0)
-                return log_error_errno(errno, "Failed to remount %s read-only: %m", cgroup_root);
-
-        return 0;
-}
-
-static int mount_unified_cgroups(const char *dest) {
-        const char *p;
-        int r;
-
-        assert(dest);
-
-        p = strjoina(dest, "/sys/fs/cgroup");
-
-        r = path_is_mount_point(p, AT_SYMLINK_FOLLOW);
-        if (r < 0)
-                return log_error_errno(r, "Failed to determine if %s is mounted already: %m", p);
-        if (r > 0) {
-                p = strjoina(dest, "/sys/fs/cgroup/cgroup.procs");
-                if (access(p, F_OK) >= 0)
-                        return 0;
-                if (errno != ENOENT)
-                        return log_error_errno(errno, "Failed to determine if mount point %s contains the unified cgroup hierarchy: %m", p);
-
-                log_error("%s is already mounted but not a unified cgroup hierarchy. Refusing.", p);
-                return -EINVAL;
-        }
-
-        if (mount("cgroup", p, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior") < 0)
-                return log_error_errno(errno, "Failed to mount unified cgroup hierarchy to %s: %m", p);
-
-        return 0;
-}
-
-static int mount_cgroups(const char *dest) {
-        if (arg_unified_cgroup_hierarchy)
-                return mount_unified_cgroups(dest);
-        else
-                return mount_legacy_cgroups(dest);
-}
-
-static int mount_systemd_cgroup_writable(const char *dest) {
-        _cleanup_free_ char *own_cgroup_path = NULL;
-        const char *systemd_root, *systemd_own;
-        int r;
-
-        assert(dest);
-
-        r = cg_pid_get_path(NULL, 0, &own_cgroup_path);
-        if (r < 0)
-                return log_error_errno(r, "Failed to determine our own cgroup path: %m");
-
-        /* If we are living in the top-level, then there's nothing to do... */
-        if (path_equal(own_cgroup_path, "/"))
-                return 0;
-
-        if (arg_unified_cgroup_hierarchy) {
-                systemd_own = strjoina(dest, "/sys/fs/cgroup", own_cgroup_path);
-                systemd_root = prefix_roota(dest, "/sys/fs/cgroup");
-        } else {
-                systemd_own = strjoina(dest, "/sys/fs/cgroup/systemd", own_cgroup_path);
-                systemd_root = prefix_roota(dest, "/sys/fs/cgroup/systemd");
-        }
-
-        /* Make our own cgroup a (writable) bind mount */
-        if (mount(systemd_own, systemd_own,  NULL, MS_BIND, NULL) < 0)
-                return log_error_errno(errno, "Failed to turn %s into a bind mount: %m", own_cgroup_path);
-
-        /* And then remount the systemd cgroup root read-only */
-        if (mount(NULL, systemd_root, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0)
-                return log_error_errno(errno, "Failed to mount cgroup root read-only: %m");
-
-        return 0;
-}
-
 static int userns_lchown(const char *p, uid_t uid, gid_t gid) {
         assert(p);
 
@@ -1837,114 +1082,6 @@ static int setup_resolv_conf(const char *dest) {
         return 0;
 }
 
-static int setup_volatile_state(const char *directory) {
-        _cleanup_free_ char *buf = NULL;
-        const char *p, *options;
-        int r;
-
-        assert(directory);
-
-        if (arg_volatile_mode != VOLATILE_STATE)
-                return 0;
-
-        /* --volatile=state means we simply overmount /var
-           with a tmpfs, and the rest read-only. */
-
-        r = bind_remount_recursive(directory, true);
-        if (r < 0)
-                return log_error_errno(r, "Failed to remount %s read-only: %m", directory);
-
-        p = prefix_roota(directory, "/var");
-        r = mkdir(p, 0755);
-        if (r < 0 && errno != EEXIST)
-                return log_error_errno(errno, "Failed to create %s: %m", directory);
-
-        options = "mode=755";
-        r = tmpfs_patch_options(options, &buf);
-        if (r < 0)
-                return log_oom();
-        if (r > 0)
-                options = buf;
-
-        if (mount("tmpfs", p, "tmpfs", MS_STRICTATIME, options) < 0)
-                return log_error_errno(errno, "Failed to mount tmpfs to /var: %m");
-
-        return 0;
-}
-
-static int setup_volatile(const char *directory) {
-        bool tmpfs_mounted = false, bind_mounted = false;
-        char template[] = "/tmp/nspawn-volatile-XXXXXX";
-        _cleanup_free_ char *buf = NULL;
-        const char *f, *t, *options;
-        int r;
-
-        assert(directory);
-
-        if (arg_volatile_mode != VOLATILE_YES)
-                return 0;
-
-        /* --volatile=yes means we mount a tmpfs to the root dir, and
-           the original /usr to use inside it, and that read-only. */
-
-        if (!mkdtemp(template))
-                return log_error_errno(errno, "Failed to create temporary directory: %m");
-
-        options = "mode=755";
-        r = tmpfs_patch_options(options, &buf);
-        if (r < 0)
-                return log_oom();
-        if (r > 0)
-                options = buf;
-
-        if (mount("tmpfs", template, "tmpfs", MS_STRICTATIME, options) < 0) {
-                r = log_error_errno(errno, "Failed to mount tmpfs for root directory: %m");
-                goto fail;
-        }
-
-        tmpfs_mounted = true;
-
-        f = prefix_roota(directory, "/usr");
-        t = prefix_roota(template, "/usr");
-
-        r = mkdir(t, 0755);
-        if (r < 0 && errno != EEXIST) {
-                r = log_error_errno(errno, "Failed to create %s: %m", t);
-                goto fail;
-        }
-
-        if (mount(f, t, NULL, MS_BIND|MS_REC, NULL) < 0) {
-                r = log_error_errno(errno, "Failed to create /usr bind mount: %m");
-                goto fail;
-        }
-
-        bind_mounted = true;
-
-        r = bind_remount_recursive(t, true);
-        if (r < 0) {
-                log_error_errno(r, "Failed to remount %s read-only: %m", t);
-                goto fail;
-        }
-
-        if (mount(template, directory, NULL, MS_MOVE, NULL) < 0) {
-                r = log_error_errno(errno, "Failed to move root mount: %m");
-                goto fail;
-        }
-
-        (void) rmdir(template);
-
-        return 0;
-
-fail:
-        if (bind_mounted)
-                (void) umount(t);
-
-        if (tmpfs_mounted)
-                (void) umount(template);
-        (void) rmdir(template);
-        return r;
-}
-
 static char* id128_format_as_uuid(sd_id128_t id, char s[37]) {
         assert(s);
 
@@ -2183,141 +1320,6 @@ static int setup_kmsg(const char *dest, int kmsg_socket) {
         return 0;
 }
 
-static int send_rtnl(int send_fd) {
-        union {
-                struct cmsghdr cmsghdr;
-                uint8_t buf[CMSG_SPACE(sizeof(int))];
-        } control = {};
-        struct msghdr mh = {
-                .msg_control = &control,
-                .msg_controllen = sizeof(control),
-        };
-        struct cmsghdr *cmsg;
-        _cleanup_close_ int fd = -1;
-        ssize_t k;
-
-        assert(send_fd >= 0);
-
-        if (!arg_expose_ports)
-                return 0;
-
-        fd = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_ROUTE);
-        if (fd < 0)
-                return log_error_errno(errno, "Failed to allocate container netlink: %m");
-
-        cmsg = CMSG_FIRSTHDR(&mh);
-        cmsg->cmsg_level = SOL_SOCKET;
-        cmsg->cmsg_type = SCM_RIGHTS;
-        cmsg->cmsg_len = CMSG_LEN(sizeof(int));
-        memcpy(CMSG_DATA(cmsg), &fd, sizeof(int));
-
-        mh.msg_controllen = cmsg->cmsg_len;
-
-        /* Store away the fd in the socket, so that it stays open as
-         * long as we run the child */
-        k = sendmsg(send_fd, &mh, MSG_NOSIGNAL);
-        if (k < 0)
-                return log_error_errno(errno, "Failed to send netlink fd: %m");
-
-        return 0;
-}
-
-static int flush_ports(union in_addr_union *exposed) {
-        ExposePort *p;
-        int r, af = AF_INET;
-
-        assert(exposed);
-
-        if (!arg_expose_ports)
-                return 0;
-
-        if (in_addr_is_null(af, exposed))
-                return 0;
-
-        log_debug("Lost IP address.");
-
-        LIST_FOREACH(ports, p, arg_expose_ports) {
-                r = fw_add_local_dnat(false,
-                                      af,
-                                      p->protocol,
-                                      NULL,
-                                      NULL, 0,
-                                      NULL, 0,
-                                      p->host_port,
-                                      exposed,
-                                      p->container_port,
-                                      NULL);
-                if (r < 0)
-                        log_warning_errno(r, "Failed to modify firewall: %m");
-        }
-
-        *exposed = IN_ADDR_NULL;
-        return 0;
-}
-
-static int expose_ports(sd_netlink *rtnl, union in_addr_union *exposed) {
-        _cleanup_free_ struct local_address *addresses = NULL;
-        _cleanup_free_ char *pretty = NULL;
-        union in_addr_union new_exposed;
-        ExposePort *p;
-        bool add;
-        int af = AF_INET, r;
-
-        assert(exposed);
-
-        /* Invoked each time an address is added or removed inside the
-         * container */
-
-        if (!arg_expose_ports)
-                return 0;
-
-        r = local_addresses(rtnl, 0, af, &addresses);
-        if (r < 0)
-                return log_error_errno(r, "Failed to enumerate local addresses: %m");
-
-        add = r > 0 &&
-                addresses[0].family == af &&
-                addresses[0].scope < RT_SCOPE_LINK;
-
-        if (!add)
-                return flush_ports(exposed);
-
-        new_exposed = addresses[0].address;
-        if (in_addr_equal(af, exposed, &new_exposed))
-                return 0;
-
-        in_addr_to_string(af, &new_exposed, &pretty);
-        log_debug("New container IP is %s.", strna(pretty));
-
-        LIST_FOREACH(ports, p, arg_expose_ports) {
-
-                r = fw_add_local_dnat(true,
-                                      af,
-                                      p->protocol,
-                                      NULL,
-                                      NULL, 0,
-                                      NULL, 0,
-                                      p->host_port,
-                                      &new_exposed,
-                                      p->container_port,
-                                      in_addr_is_null(af, exposed) ? NULL : exposed);
-                if (r < 0)
-                        log_warning_errno(r, "Failed to modify firewall: %m");
-        }
-
-        *exposed = new_exposed;
-        return 0;
-}
-
-void expose_port_free_all(ExposePort *p) {
-
-        while (p) {
-                ExposePort *q = p;
-                LIST_REMOVE(ports, p, q);
-                free(q);
-        }
-}
-
 static int on_address_change(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) {
         union in_addr_union *exposed = userdata;
 
@@ -2325,62 +1327,7 @@ static int on_address_change(sd_netlink *rtnl, sd_netlink_message *m, void *user
         assert(m);
         assert(exposed);
 
-        expose_ports(rtnl, exposed);
-        return 0;
-}
-
-static int watch_rtnl(sd_event *event, int recv_fd, union in_addr_union *exposed, sd_netlink **ret) {
-        union {
-                struct cmsghdr cmsghdr;
-                uint8_t buf[CMSG_SPACE(sizeof(int))];
-        } control = {};
-        struct msghdr mh = {
-                .msg_control = &control,
-                .msg_controllen = sizeof(control),
-        };
-        struct cmsghdr *cmsg;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        int fd, r;
-        ssize_t k;
-
-        assert(event);
-        assert(recv_fd >= 0);
-        assert(ret);
-
-        if (!arg_expose_ports)
-                return 0;
-
-        k = recvmsg(recv_fd, &mh, MSG_NOSIGNAL);
-        if (k < 0)
-                return log_error_errno(errno, "Failed to recv netlink fd: %m");
-
-        cmsg = CMSG_FIRSTHDR(&mh);
-        assert(cmsg->cmsg_level == SOL_SOCKET);
-        assert(cmsg->cmsg_type == SCM_RIGHTS);
-        assert(cmsg->cmsg_len == CMSG_LEN(sizeof(int)));
-        memcpy(&fd, CMSG_DATA(cmsg), sizeof(int));
-
-        r = sd_netlink_open_fd(&rtnl, fd);
-        if (r < 0) {
-                safe_close(fd);
-                return log_error_errno(r, "Failed to create rtnl object: %m");
-        }
-
-        r = sd_netlink_add_match(rtnl, RTM_NEWADDR, on_address_change, exposed);
-        if (r < 0)
-                return log_error_errno(r, "Failed to subscribe to RTM_NEWADDR messages: %m");
-
-        r = sd_netlink_add_match(rtnl, RTM_DELADDR, on_address_change, exposed);
-        if (r < 0)
-                return log_error_errno(r, "Failed to subscribe to RTM_DELADDR messages: %m");
-
-        r = sd_netlink_attach_event(rtnl, event, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add to even loop: %m");
-
-        *ret = rtnl;
-        rtnl = NULL;
-
+        expose_port_execute(rtnl, arg_expose_ports, exposed);
         return 0;
 }
 
@@ -2557,220 +1504,6 @@ static int drop_capabilities(void) {
         return capability_bounding_set_drop(~arg_retain, false);
 }
 
-static int register_machine(pid_t pid, int local_ifindex) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
-        int r;
-
-        if (!arg_register)
-                return 0;
-
-        r = sd_bus_default_system(&bus);
-        if (r < 0)
-                return log_error_errno(r, "Failed to open system bus: %m");
-
-        if (arg_keep_unit) {
-                r = sd_bus_call_method(
-                                bus,
-                                "org.freedesktop.machine1",
-                                "/org/freedesktop/machine1",
-                                "org.freedesktop.machine1.Manager",
-                                "RegisterMachineWithNetwork",
-                                &error,
-                                NULL,
-                                "sayssusai",
-                                arg_machine,
-                                SD_BUS_MESSAGE_APPEND_ID128(arg_uuid),
-                                "nspawn",
-                                "container",
-                                (uint32_t) pid,
-                                strempty(arg_directory),
-                                local_ifindex > 0 ? 1 : 0, local_ifindex);
-        } else {
-                _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
-                char **i;
-                unsigned j;
-
-                r = sd_bus_message_new_method_call(
-                                bus,
-                                &m,
-                                "org.freedesktop.machine1",
-                                "/org/freedesktop/machine1",
-                                "org.freedesktop.machine1.Manager",
-                                "CreateMachineWithNetwork");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_append(
-                                m,
-                                "sayssusai",
-                                arg_machine,
-                                SD_BUS_MESSAGE_APPEND_ID128(arg_uuid),
-                                "nspawn",
-                                "container",
-                                (uint32_t) pid,
-                                strempty(arg_directory),
-                                local_ifindex > 0 ? 1 : 0, local_ifindex);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_message_open_container(m, 'a', "(sv)");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                if (!isempty(arg_slice)) {
-                        r = sd_bus_message_append(m, "(sv)", "Slice", "s", arg_slice);
-                        if (r < 0)
-                                return bus_log_create_error(r);
-                }
-
-                r = sd_bus_message_append(m, "(sv)", "DevicePolicy", "s", "strict");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                /* If you make changes here, also make sure to update
-                 * systemd-nspawn@.service, to keep the device
-                 * policies in sync regardless if we are run with or
-                 * without the --keep-unit switch. */
-                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 9,
-                                          /* Allow the container to
-                                           * access and create the API
-                                           * device nodes, so that
-                                           * PrivateDevices= in the
-                                           * container can work
-                                           * fine */
-                                          "/dev/null", "rwm",
-                                          "/dev/zero", "rwm",
-                                          "/dev/full", "rwm",
-                                          "/dev/random", "rwm",
-                                          "/dev/urandom", "rwm",
-                                          "/dev/tty", "rwm",
-                                          "/dev/net/tun", "rwm",
-                                          /* Allow the container
-                                           * access to ptys. However,
-                                           * do not permit the
-                                           * container to ever create
-                                           * these device nodes. */
-                                          "/dev/pts/ptmx", "rw",
-                                          "char-pts", "rw");
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                for (j = 0; j < arg_n_custom_mounts; j++) {
-                        CustomMount *cm = &arg_custom_mounts[j];
-
-                        if (cm->type != CUSTOM_MOUNT_BIND)
-                                continue;
-
-                        r = is_device_node(cm->source);
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to stat %s: %m", cm->source);
-
-                        if (r) {
-                                r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 1,
-                                        cm->source, cm->read_only ? "r" : "rw");
-                                if (r < 0)
-                                        return log_error_errno(r, "Failed to append message arguments: %m");
-                        }
-                }
-
-                if (arg_kill_signal != 0) {
-                        r = sd_bus_message_append(m, "(sv)", "KillSignal", "i", arg_kill_signal);
-                        if (r < 0)
-                                return bus_log_create_error(r);
-
-                        r = sd_bus_message_append(m, "(sv)", "KillMode", "s", "mixed");
-                        if (r < 0)
-                                return bus_log_create_error(r);
-                }
-
-                STRV_FOREACH(i, arg_property) {
-                        r = sd_bus_message_open_container(m, 'r', "sv");
-                        if (r < 0)
-                                return bus_log_create_error(r);
-
-                        r = bus_append_unit_property_assignment(m, *i);
-                        if (r < 0)
-                                return r;
-
-                        r = sd_bus_message_close_container(m);
-                        if (r < 0)
-                                return bus_log_create_error(r);
-                }
-
-                r = sd_bus_message_close_container(m);
-                if (r < 0)
-                        return bus_log_create_error(r);
-
-                r = sd_bus_call(bus, m, 0, &error, NULL);
-        }
-
-        if (r < 0) {
-                log_error("Failed to register machine: %s", bus_error_message(&error, r));
-                return r;
-        }
-
-        return 0;
-}
-
-static int terminate_machine(pid_t pid) {
-        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
-        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
-        const char *path;
-        int r;
-
-        if (!arg_register)
-                return 0;
-
-        /* If we are reusing the unit, then just exit, systemd will do
-         * the right thing when we exit. */
-        if (arg_keep_unit)
-                return 0;
-
-        r = sd_bus_default_system(&bus);
-        if (r < 0)
-                return log_error_errno(r, "Failed to open system bus: %m");
-
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.machine1",
-                        "/org/freedesktop/machine1",
-                        "org.freedesktop.machine1.Manager",
-                        "GetMachineByPID",
-                        &error,
-                        &reply,
-                        "u",
-                        (uint32_t) pid);
-        if (r < 0) {
-                /* Note that the machine might already have been
-                 * cleaned up automatically, hence don't consider it a
-                 * failure if we cannot get the machine object. */
-                log_debug("Failed to get machine: %s", bus_error_message(&error, r));
-                return 0;
-        }
-
-        r = sd_bus_message_read(reply, "o", &path);
-        if (r < 0)
-                return bus_log_parse_error(r);
-
-        r = sd_bus_call_method(
-                        bus,
-                        "org.freedesktop.machine1",
-                        path,
-                        "org.freedesktop.machine1.Machine",
-                        "Terminate",
-                        &error,
-                        NULL,
-                        NULL);
-        if (r < 0) {
-                log_debug("Failed to terminate machine: %s", bus_error_message(&error, r));
-                return 0;
-        }
-
-        return 0;
-}
-
 static int reset_audit_loginuid(void) {
         _cleanup_free_ char *p = NULL;
         int r;
@@ -2803,427 +1536,6 @@ static int reset_audit_loginuid(void) {
         return 0;
 }
 
-#define HOST_HASH_KEY SD_ID128_MAKE(1a,37,6f,c7,46,ec,45,0b,ad,a3,d5,31,06,60,5d,b1)
-#define CONTAINER_HASH_KEY SD_ID128_MAKE(c3,c4,f9,19,b5,57,b2,1c,e6,cf,14,27,03,9c,ee,a2)
-#define MACVLAN_HASH_KEY SD_ID128_MAKE(00,13,6d,bc,66,83,44,81,bb,0c,f9,51,1f,24,a6,6f)
-
-static int generate_mac(struct ether_addr *mac, sd_id128_t hash_key, uint64_t idx) {
-        uint8_t result[8];
-        size_t l, sz;
-        uint8_t *v, *i;
-        int r;
-
-        l = strlen(arg_machine);
-        sz = sizeof(sd_id128_t) + l;
-        if (idx > 0)
-                sz += sizeof(idx);
-
-        v = alloca(sz);
-
-        /* fetch some persistent data unique to the host */
-        r = sd_id128_get_machine((sd_id128_t*) v);
-        if (r < 0)
-                return r;
-
-        /* combine with some data unique (on this host) to this
-         * container instance */
-        i = mempcpy(v + sizeof(sd_id128_t), arg_machine, l);
-        if (idx > 0) {
-                idx = htole64(idx);
-                memcpy(i, &idx, sizeof(idx));
-        }
-
-        /* Let's hash the host machine ID plus the container name. We
-         * use a fixed, but originally randomly created hash key here. */
-        siphash24(result, v, sz, hash_key.bytes);
-
-        assert_cc(ETH_ALEN <= sizeof(result));
-        memcpy(mac->ether_addr_octet, result, ETH_ALEN);
-
-        /* see eth_random_addr in the kernel */
-        mac->ether_addr_octet[0] &= 0xfe;        /* clear multicast bit */
-        mac->ether_addr_octet[0] |= 0x02;        /* set local assignment bit (IEEE802) */
-
-        return 0;
-}
-
-static int setup_veth(pid_t pid, char iface_name[IFNAMSIZ], int *ifi) {
-        _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        struct ether_addr mac_host, mac_container;
-        int r, i;
-
-        if (!arg_private_network)
-                return 0;
-
-        if (!arg_network_veth)
-                return 0;
-
-        /* Use two different interface name prefixes depending whether
-         * we are in bridge mode or not. */
-        snprintf(iface_name, IFNAMSIZ - 1, "%s-%s",
-                 arg_network_bridge ? "vb" : "ve", arg_machine);
-
-        r = generate_mac(&mac_container, CONTAINER_HASH_KEY, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to generate predictable MAC address for container side: %m");
-
-        r = generate_mac(&mac_host, HOST_HASH_KEY, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to generate predictable MAC address for host side: %m");
-
-        r = sd_netlink_open(&rtnl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to connect to netlink: %m");
-
-        r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to allocate netlink message: %m");
-
-        r = sd_netlink_message_append_string(m, IFLA_IFNAME, iface_name);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink interface name: %m");
-
-        r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac_host);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
-        r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
-        if (r < 0)
-                return log_error_errno(r, "Failed to open netlink container: %m");
-
-        r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "veth");
-        if (r < 0)
-                return log_error_errno(r, "Failed to open netlink container: %m");
-
-        r = sd_netlink_message_open_container(m, VETH_INFO_PEER);
-        if (r < 0)
-                return log_error_errno(r, "Failed to open netlink container: %m");
-
-        r = sd_netlink_message_append_string(m, IFLA_IFNAME, "host0");
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink interface name: %m");
-
-        r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac_container);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
-        r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
-        r = sd_netlink_message_close_container(m);
-        if (r < 0)
-                return log_error_errno(r, "Failed to close netlink container: %m");
-
-        r = sd_netlink_message_close_container(m);
-        if (r < 0)
-                return log_error_errno(r, "Failed to close netlink container: %m");
-
-        r = sd_netlink_message_close_container(m);
-        if (r < 0)
-                return log_error_errno(r, "Failed to close netlink container: %m");
-
-        r = sd_netlink_call(rtnl, m, 0, NULL);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add new veth interfaces (host0, %s): %m", iface_name);
-
-        i = (int) if_nametoindex(iface_name);
-        if (i <= 0)
-                return log_error_errno(errno, "Failed to resolve interface %s: %m", iface_name);
-
-        *ifi = i;
-
-        return 0;
-}
-
-static int setup_bridge(const char veth_name[], int *ifi) {
-        _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        int r, bridge;
-
-        if (!arg_private_network)
-                return 0;
-
-        if (!arg_network_veth)
-                return 0;
-
-        if (!arg_network_bridge)
-                return 0;
-
-        bridge = (int) if_nametoindex(arg_network_bridge);
-        if (bridge <= 0)
-                return log_error_errno(errno, "Failed to resolve interface %s: %m", arg_network_bridge);
-
-        *ifi = bridge;
-
-        r = sd_netlink_open(&rtnl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to connect to netlink: %m");
-
-        r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to allocate netlink message: %m");
-
-        r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP);
-        if (r < 0)
-                return log_error_errno(r, "Failed to set IFF_UP flag: %m");
-
-        r = sd_netlink_message_append_string(m, IFLA_IFNAME, veth_name);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink interface name field: %m");
-
-        r = sd_netlink_message_append_u32(m, IFLA_MASTER, bridge);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add netlink master field: %m");
-
-        r = sd_netlink_call(rtnl, m, 0, NULL);
-        if (r < 0)
-                return log_error_errno(r, "Failed to add veth interface to bridge: %m");
-
-        return 0;
-}
-
-static int parse_interface(struct udev *udev, const char *name) {
-        _cleanup_udev_device_unref_ struct udev_device *d = NULL;
-        char ifi_str[2 + DECIMAL_STR_MAX(int)];
-        int ifi;
-
-        ifi = (int) if_nametoindex(name);
-        if (ifi <= 0)
-                return log_error_errno(errno, "Failed to resolve interface %s: %m", name);
-
-        sprintf(ifi_str, "n%i", ifi);
-        d = udev_device_new_from_device_id(udev, ifi_str);
-        if (!d)
-                return log_error_errno(errno, "Failed to get udev device for interface %s: %m", name);
-
-        if (udev_device_get_is_initialized(d) <= 0) {
-                log_error("Network interface %s is not initialized yet.", name);
-                return -EBUSY;
-        }
-
-        return ifi;
-}
-
-static int move_network_interfaces(pid_t pid) {
-        _cleanup_udev_unref_ struct udev *udev = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        char **i;
-        int r;
-
-        if (!arg_private_network)
-                return 0;
-
-        if (strv_isempty(arg_network_interfaces))
-                return 0;
-
-        r = sd_netlink_open(&rtnl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to connect to netlink: %m");
-
-        udev = udev_new();
-        if (!udev) {
-                log_error("Failed to connect to udev.");
-                return -ENOMEM;
-        }
-
-        STRV_FOREACH(i, arg_network_interfaces) {
-                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
-                int ifi;
-
-                ifi = parse_interface(udev, *i);
-                if (ifi < 0)
-                        return ifi;
-
-                r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, ifi);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to allocate netlink message: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to append namespace PID to netlink message: %m");
-
-                r = sd_netlink_call(rtnl, m, 0, NULL);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to move interface %s to namespace: %m", *i);
-        }
-
-        return 0;
-}
-
-static int setup_macvlan(pid_t pid) {
-        _cleanup_udev_unref_ struct udev *udev = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        unsigned idx = 0;
-        char **i;
-        int r;
-
-        if (!arg_private_network)
-                return 0;
-
-        if (strv_isempty(arg_network_macvlan))
-                return 0;
-
-        r = sd_netlink_open(&rtnl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to connect to netlink: %m");
-
-        udev = udev_new();
-        if (!udev) {
-                log_error("Failed to connect to udev.");
-                return -ENOMEM;
-        }
-
-        STRV_FOREACH(i, arg_network_macvlan) {
-                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
-                _cleanup_free_ char *n = NULL;
-                struct ether_addr mac;
-                int ifi;
-
-                ifi = parse_interface(udev, *i);
-                if (ifi < 0)
-                        return ifi;
-
-                r = generate_mac(&mac, MACVLAN_HASH_KEY, idx++);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to create MACVLAN MAC address: %m");
-
-                r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to allocate netlink message: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink interface index: %m");
-
-                n = strappend("mv-", *i);
-                if (!n)
-                        return log_oom();
-
-                strshorten(n, IFNAMSIZ-1);
-
-                r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink interface name: %m");
-
-                r = sd_netlink_message_append_ether_addr(m, IFLA_ADDRESS, &mac);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink MAC address: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
-                r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to open netlink container: %m");
-
-                r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "macvlan");
-                if (r < 0)
-                        return log_error_errno(r, "Failed to open netlink container: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_MACVLAN_MODE, MACVLAN_MODE_BRIDGE);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to append macvlan mode: %m");
-
-                r = sd_netlink_message_close_container(m);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to close netlink container: %m");
-
-                r = sd_netlink_message_close_container(m);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to close netlink container: %m");
-
-                r = sd_netlink_call(rtnl, m, 0, NULL);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add new macvlan interfaces: %m");
-        }
-
-        return 0;
-}
-
-static int setup_ipvlan(pid_t pid) {
-        _cleanup_udev_unref_ struct udev *udev = NULL;
-        _cleanup_netlink_unref_ sd_netlink *rtnl = NULL;
-        char **i;
-        int r;
-
-        if (!arg_private_network)
-                return 0;
-
-        if (strv_isempty(arg_network_ipvlan))
-                return 0;
-
-        r = sd_netlink_open(&rtnl);
-        if (r < 0)
-                return log_error_errno(r, "Failed to connect to netlink: %m");
-
-        udev = udev_new();
-        if (!udev) {
-                log_error("Failed to connect to udev.");
-                return -ENOMEM;
-        }
-
-        STRV_FOREACH(i, arg_network_ipvlan) {
-                _cleanup_netlink_message_unref_ sd_netlink_message *m = NULL;
-                _cleanup_free_ char *n = NULL;
-                int ifi;
-
-                ifi = parse_interface(udev, *i);
-                if (ifi < 0)
-                        return ifi;
-
-                r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to allocate netlink message: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_LINK, ifi);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink interface index: %m");
-
-                n = strappend("iv-", *i);
-                if (!n)
-                        return log_oom();
-
-                strshorten(n, IFNAMSIZ-1);
-
-                r = sd_netlink_message_append_string(m, IFLA_IFNAME, n);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink interface name: %m");
-
-                r = sd_netlink_message_append_u32(m, IFLA_NET_NS_PID, pid);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add netlink namespace field: %m");
-
-                r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to open netlink container: %m");
-
-                r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "ipvlan");
-                if (r < 0)
-                        return log_error_errno(r, "Failed to open netlink container: %m");
-
-                r = sd_netlink_message_append_u16(m, IFLA_IPVLAN_MODE, IPVLAN_MODE_L2);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add ipvlan mode: %m");
-
-                r = sd_netlink_message_close_container(m);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to close netlink container: %m");
-
-                r = sd_netlink_message_close_container(m);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to close netlink container: %m");
-
-                r = sd_netlink_call(rtnl, m, 0, NULL);
-                if (r < 0)
-                        return log_error_errno(r, "Failed to add new ipvlan interfaces: %m");
-        }
-
-        return 0;
-}
-
 static int setup_seccomp(void) {
 
 #ifdef HAVE_SECCOMP
@@ -3922,247 +2234,6 @@ static void loop_remove(int nr, int *image_fd) {
                 log_debug_errno(errno, "Failed to remove loop %d: %m", nr);
 }
 
-static int spawn_getent(const char *database, const char *key, pid_t *rpid) {
-        int pipe_fds[2];
-        pid_t pid;
-
-        assert(database);
-        assert(key);
-        assert(rpid);
-
-        if (pipe2(pipe_fds, O_CLOEXEC) < 0)
-                return log_error_errno(errno, "Failed to allocate pipe: %m");
-
-        pid = fork();
-        if (pid < 0)
-                return log_error_errno(errno, "Failed to fork getent child: %m");
-        else if (pid == 0) {
-                int nullfd;
-                char *empty_env = NULL;
-
-                if (dup3(pipe_fds[1], STDOUT_FILENO, 0) < 0)
-                        _exit(EXIT_FAILURE);
-
-                if (pipe_fds[0] > 2)
-                        safe_close(pipe_fds[0]);
-                if (pipe_fds[1] > 2)
-                        safe_close(pipe_fds[1]);
-
-                nullfd = open("/dev/null", O_RDWR);
-                if (nullfd < 0)
-                        _exit(EXIT_FAILURE);
-
-                if (dup3(nullfd, STDIN_FILENO, 0) < 0)
-                        _exit(EXIT_FAILURE);
-
-                if (dup3(nullfd, STDERR_FILENO, 0) < 0)
-                        _exit(EXIT_FAILURE);
-
-                if (nullfd > 2)
-                        safe_close(nullfd);
-
-                (void) reset_all_signal_handlers();
-                (void) reset_signal_mask();
-                close_all_fds(NULL, 0);
-
-                execle("/usr/bin/getent", "getent", database, key, NULL, &empty_env);
-                execle("/bin/getent", "getent", database, key, NULL, &empty_env);
-                _exit(EXIT_FAILURE);
-        }
-
-        pipe_fds[1] = safe_close(pipe_fds[1]);
-
-        *rpid = pid;
-
-        return pipe_fds[0];
-}
-
-static int change_uid_gid(char **_home) {
-        char line[LINE_MAX], *x, *u, *g, *h;
-        const char *word, *state;
-        _cleanup_free_ uid_t *uids = NULL;
-        _cleanup_free_ char *home = NULL;
-        _cleanup_fclose_ FILE *f = NULL;
-        _cleanup_close_ int fd = -1;
-        unsigned n_uids = 0;
-        size_t sz = 0, l;
-        uid_t uid;
-        gid_t gid;
-        pid_t pid;
-        int r;
-
-        assert(_home);
-
-        if (!arg_user || streq(arg_user, "root") || streq(arg_user, "0")) {
-                /* Reset everything fully to 0, just in case */
-
-                r = reset_uid_gid();
-                if (r < 0)
-                        return log_error_errno(r, "Failed to become root: %m");
-
-                *_home = NULL;
-                return 0;
-        }
-
-        /* First, get user credentials */
-        fd = spawn_getent("passwd", arg_user, &pid);
-        if (fd < 0)
-                return fd;
-
-        f = fdopen(fd, "r");
-        if (!f)
-                return log_oom();
-        fd = -1;
-
-        if (!fgets(line, sizeof(line), f)) {
-
-                if (!ferror(f)) {
-                        log_error("Failed to resolve user %s.", arg_user);
-                        return -ESRCH;
-                }
-
-                log_error_errno(errno, "Failed to read from getent: %m");
-                return -errno;
-        }
-
-        truncate_nl(line);
-
-        wait_for_terminate_and_warn("getent passwd", pid, true);
-
-        x = strchr(line, ':');
-        if (!x) {
-                log_error("/etc/passwd entry has invalid user field.");
-                return -EIO;
-        }
-
-        u = strchr(x+1, ':');
-        if (!u) {
-                log_error("/etc/passwd entry has invalid password field.");
-                return -EIO;
-        }
-
-        u++;
-        g = strchr(u, ':');
-        if (!g) {
-                log_error("/etc/passwd entry has invalid UID field.");
-                return -EIO;
-        }
-
-        *g = 0;
-        g++;
-        x = strchr(g, ':');
-        if (!x) {
-                log_error("/etc/passwd entry has invalid GID field.");
-                return -EIO;
-        }
-
-        *x = 0;
-        h = strchr(x+1, ':');
-        if (!h) {
-                log_error("/etc/passwd entry has invalid GECOS field.");
-                return -EIO;
-        }
-
-        h++;
-        x = strchr(h, ':');
-        if (!x) {
-                log_error("/etc/passwd entry has invalid home directory field.");
-                return -EIO;
-        }
-
-        *x = 0;
-
-        r = parse_uid(u, &uid);
-        if (r < 0) {
-                log_error("Failed to parse UID of user.");
-                return -EIO;
-        }
-
-        r = parse_gid(g, &gid);
-        if (r < 0) {
-                log_error("Failed to parse GID of user.");
-                return -EIO;
-        }
-
-        home = strdup(h);
-        if (!home)
-                return log_oom();
-
-        /* Second, get group memberships */
-        fd = spawn_getent("initgroups", arg_user, &pid);
-        if (fd < 0)
-                return fd;
-
-        fclose(f);
-        f = fdopen(fd, "r");
-        if (!f)
-                return log_oom();
-        fd = -1;
-
-        if (!fgets(line, sizeof(line), f)) {
-                if (!ferror(f)) {
-                        log_error("Failed to resolve user %s.", arg_user);
-                        return -ESRCH;
-                }
-
-                log_error_errno(errno, "Failed to read from getent: %m");
-                return -errno;
-        }
-
-        truncate_nl(line);
-
-        wait_for_terminate_and_warn("getent initgroups", pid, true);
-
-        /* Skip over the username and subsequent separator whitespace */
-        x = line;
-        x += strcspn(x, WHITESPACE);
-        x += strspn(x, WHITESPACE);
-
-        FOREACH_WORD(word, l, x, state) {
-                char c[l+1];
-
-                memcpy(c, word, l);
-                c[l] = 0;
-
-                if (!GREEDY_REALLOC(uids, sz, n_uids+1))
-                        return log_oom();
-
-                r = parse_uid(c, &uids[n_uids++]);
-                if (r < 0) {
-                        log_error("Failed to parse group data from getent.");
-                        return -EIO;
-                }
-        }
-
-        r = mkdir_parents(home, 0775);
-        if (r < 0)
-                return log_error_errno(r, "Failed to make home root directory: %m");
-
-        r = mkdir_safe(home, 0755, uid, gid);
-        if (r < 0 && r != -EEXIST)
-                return log_error_errno(r, "Failed to make home directory: %m");
-
-        (void) fchown(STDIN_FILENO, uid, gid);
-        (void) fchown(STDOUT_FILENO, uid, gid);
-        (void) fchown(STDERR_FILENO, uid, gid);
-
-        if (setgroups(n_uids, uids) < 0)
-                return log_error_errno(errno, "Failed to set auxiliary groups: %m");
-
-        if (setresgid(gid, gid, gid) < 0)
-                return log_error_errno(errno, "setregid() failed: %m");
-
-        if (setresuid(uid, uid, uid) < 0)
-                return log_error_errno(errno, "setreuid() failed: %m");
-
-        if (_home) {
-                *_home = home;
-                home = NULL;
-        }
-
-        return 0;
-}
-
 /*
  * Return values:
  * < 0 : wait_for_terminate() failed to get the state of the
@@ -4401,7 +2472,7 @@ static int inner_child(
                 }
         }
 
-        r = mount_all(NULL, true);
+        r = mount_all(NULL, true, arg_uid_shift, arg_uid_range, arg_selinux_apifs_context);
         if (r < 0)
                 return r;
 
@@ -4412,7 +2483,7 @@ static int inner_child(
                 return -ESRCH;
         }
 
-        r = mount_systemd_cgroup_writable("");
+        r = mount_systemd_cgroup_writable("", arg_unified_cgroup_hierarchy);
         if (r < 0)
                 return r;
 
@@ -4437,10 +2508,12 @@ static int inner_child(
         if (arg_private_network)
                 loopback_setup();
 
-        r = send_rtnl(rtnl_socket);
-        if (r < 0)
-                return r;
-        rtnl_socket = safe_close(rtnl_socket);
+        if (arg_expose_ports) {
+                r = expose_port_send_rtnl(rtnl_socket);
+                if (r < 0)
+                        return r;
+                rtnl_socket = safe_close(rtnl_socket);
+        }
 
         if (drop_capabilities() < 0)
                 return log_error_errno(errno, "drop_capabilities() failed: %m");
@@ -4461,7 +2534,7 @@ static int inner_child(
                         return log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context);
 #endif
 
-        r = change_uid_gid(&home);
+        r = change_uid_gid(arg_user, &home);
         if (r < 0)
                 return r;
 
@@ -4632,11 +2705,11 @@ static int outer_child(
         if (mount(directory, directory, NULL, MS_BIND|MS_REC, NULL) < 0)
                 return log_error_errno(errno, "Failed to make bind mount: %m");
 
-        r = setup_volatile(directory);
+        r = setup_volatile(directory, arg_volatile_mode, arg_userns, arg_uid_shift, arg_uid_range, arg_selinux_context);
         if (r < 0)
                 return r;
 
-        r = setup_volatile_state(directory);
+        r = setup_volatile_state(directory, arg_volatile_mode, arg_userns, arg_uid_shift, arg_uid_range, arg_selinux_context);
         if (r < 0)
                 return r;
 
@@ -4650,7 +2723,7 @@ static int outer_child(
                         return log_error_errno(r, "Failed to make tree read-only: %m");
         }
 
-        r = mount_all(directory, false);
+        r = mount_all(directory, false, arg_uid_shift, arg_uid_range, arg_selinux_apifs_context);
         if (r < 0)
                 return r;
 
@@ -4686,11 +2759,11 @@ static int outer_child(
         if (r < 0)
                 return r;
 
-        r = mount_custom(directory);
+        r = mount_custom(directory, arg_custom_mounts, arg_n_custom_mounts, arg_userns, arg_uid_shift, arg_uid_range, arg_selinux_apifs_context);
         if (r < 0)
                 return r;
 
-        r = mount_cgroups(directory);
+        r = mount_cgroups(directory, arg_unified_cgroup_hierarchy, arg_userns, arg_uid_shift, arg_uid_range, arg_selinux_apifs_context);
         if (r < 0)
                 return r;
 
@@ -4754,141 +2827,6 @@ static int setup_uid_map(pid_t pid) {
         return 0;
 }
 
-static int chown_cgroup(pid_t pid) {
-        _cleanup_free_ char *path = NULL, *fs = NULL;
-        _cleanup_close_ int fd = -1;
-        const char *fn;
-        int r;
-
-        r = cg_pid_get_path(NULL, pid, &path);
-        if (r < 0)
-                return log_error_errno(r, "Failed to get container cgroup path: %m");
-
-        r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, NULL, &fs);
-        if (r < 0)
-                return log_error_errno(r, "Failed to get file system path for container cgroup: %m");
-
-        fd = open(fs, O_RDONLY|O_CLOEXEC|O_DIRECTORY);
-        if (fd < 0)
-                return log_error_errno(errno, "Failed to open %s: %m", fs);
-
-        FOREACH_STRING(fn,
-                       ".",
-                       "tasks",
-                       "notify_on_release",
-                       "cgroup.procs",
-                       "cgroup.clone_children",
-                       "cgroup.controllers",
-                       "cgroup.subtree_control",
-                       "cgroup.populated")
-                if (fchownat(fd, fn, arg_uid_shift, arg_uid_shift, 0) < 0)
-                        log_full_errno(errno == ENOENT ? LOG_DEBUG :  LOG_WARNING, errno,
-                                       "Failed to chown() cgroup file %s, ignoring: %m", fn);
-
-        return 0;
-}
-
-static int sync_cgroup(pid_t pid) {
-        _cleanup_free_ char *cgroup = NULL;
-        char tree[] = "/tmp/unifiedXXXXXX", pid_string[DECIMAL_STR_MAX(pid) + 1];
-        bool undo_mount = false;
-        const char *fn;
-        int unified, r;
-
-        unified = cg_unified();
-        if (unified < 0)
-                return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m");
-
-        if ((unified > 0) == arg_unified_cgroup_hierarchy)
-                return 0;
-
-        /* When the host uses the legacy cgroup setup, but the
-         * container shall use the unified hierarchy, let's make sure
-         * we copy the path from the name=systemd hierarchy into the
-         * unified hierarchy. Similar for the reverse situation. */
-
-        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup);
-        if (r < 0)
-                return log_error_errno(r, "Failed to get control group of " PID_FMT ": %m", pid);
-
-        /* In order to access the unified hierarchy we need to mount it */
-        if (!mkdtemp(tree))
-                return log_error_errno(errno, "Failed to generate temporary mount point for unified hierarchy: %m");
-
-        if (unified)
-                r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "none,name=systemd,xattr");
-        else
-                r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior");
-        if (r < 0) {
-                r = log_error_errno(errno, "Failed to mount unified hierarchy: %m");
-                goto finish;
-        }
-
-        undo_mount = true;
-
-        fn = strjoina(tree, cgroup, "/cgroup.procs");
-        (void) mkdir_parents(fn, 0755);
-
-        sprintf(pid_string, PID_FMT, pid);
-        r = write_string_file(fn, pid_string, 0);
-        if (r < 0)
-                log_error_errno(r, "Failed to move process: %m");
-
-finish:
-        if (undo_mount)
-                (void) umount(tree);
-
-        (void) rmdir(tree);
-        return r;
-}
-
-static int create_subcgroup(pid_t pid) {
-        _cleanup_free_ char *cgroup = NULL;
-        const char *child;
-        int unified, r;
-        CGroupMask supported;
-
-        /* In the unified hierarchy inner nodes may only only contain
-         * subgroups, but not processes. Hence, if we running in the
-         * unified hierarchy and the container does the same, and we
-         * did not create a scope unit for the container move us and
-         * the container into two separate subcgroups. */
-
-        if (!arg_keep_unit)
-                return 0;
-
-        if (!arg_unified_cgroup_hierarchy)
-                return 0;
-
-        unified = cg_unified();
-        if (unified < 0)
-                return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m");
-        if (unified == 0)
-                return 0;
-
-        r = cg_mask_supported(&supported);
-        if (r < 0)
-                return log_error_errno(r, "Failed to determine supported controllers: %m");
-
-        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup);
-        if (r < 0)
-                return log_error_errno(r, "Failed to get our control group: %m");
-
-        child = strjoina(cgroup, "/payload");
-        r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, pid);
-        if (r < 0)
-                return log_error_errno(r, "Failed to create %s subcgroup: %m", child);
-
-        child = strjoina(cgroup, "/supervisor");
-        r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, 0);
-        if (r < 0)
-                return log_error_errno(r, "Failed to create %s subcgroup: %m", child);
-
-        /* Try to enable as many controllers as possible for the new payload. */
-        (void) cg_enable_everywhere(supported, supported, cgroup);
-        return 0;
-}
-
 static int load_settings(void) {
         _cleanup_(settings_freep) Settings *settings = NULL;
         _cleanup_fclose_ FILE *f = NULL;
@@ -5469,39 +3407,64 @@ int main(int argc, char *argv[]) {
                         (void) barrier_place(&barrier); /* #2 */
                 }
 
-                r = move_network_interfaces(pid);
-                if (r < 0)
-                        goto finish;
+                if (arg_private_network) {
 
-                r = setup_veth(pid, veth_name, &ifi);
-                if (r < 0)
-                        goto finish;
+                        r = move_network_interfaces(pid, arg_network_interfaces);
+                        if (r < 0)
+                                goto finish;
 
-                r = setup_bridge(veth_name, &ifi);
-                if (r < 0)
-                        goto finish;
+                        if (arg_network_veth) {
+                                r = setup_veth(arg_machine, pid, veth_name, !!arg_network_bridge);
+                                if (r < 0)
+                                        goto finish;
+                                else if (r > 0)
+                                        ifi = r;
 
-                r = setup_macvlan(pid);
-                if (r < 0)
-                        goto finish;
+                                if (arg_network_bridge) {
+                                        r = setup_bridge(veth_name, arg_network_bridge);
+                                        if (r < 0)
+                                                goto finish;
+                                        if (r > 0)
+                                                ifi = r;
+                                }
+                        }
 
-                r = setup_ipvlan(pid);
-                if (r < 0)
-                        goto finish;
+                        r = setup_macvlan(arg_machine, pid, arg_network_macvlan);
+                        if (r < 0)
+                                goto finish;
 
-                r = register_machine(pid, ifi);
-                if (r < 0)
-                        goto finish;
+                        r = setup_ipvlan(arg_machine, pid, arg_network_ipvlan);
+                        if (r < 0)
+                                goto finish;
+                }
 
-                r = sync_cgroup(pid);
-                if (r < 0)
-                        goto finish;
+                if (arg_register) {
+                        r = register_machine(
+                                        arg_machine,
+                                        pid,
+                                        arg_directory,
+                                        arg_uuid,
+                                        ifi,
+                                        arg_slice,
+                                        arg_custom_mounts, arg_n_custom_mounts,
+                                        arg_kill_signal,
+                                        arg_property,
+                                        arg_keep_unit);
+                        if (r < 0)
+                                goto finish;
+                }
 
-                r = create_subcgroup(pid);
+                r = sync_cgroup(pid, arg_unified_cgroup_hierarchy);
                 if (r < 0)
                         goto finish;
 
-                r = chown_cgroup(pid);
+                if (arg_keep_unit) {
+                        r = create_subcgroup(pid, arg_unified_cgroup_hierarchy);
+                        if (r < 0)
+                                goto finish;
+                }
+
+                r = chown_cgroup(pid, arg_uid_shift);
                 if (r < 0)
                         goto finish;
 
@@ -5554,11 +3517,11 @@ int main(int argc, char *argv[]) {
                 sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL);
 
                 if (arg_expose_ports) {
-                        r = watch_rtnl(event, rtnl_socket_pair[0], &exposed, &rtnl);
+                        r = expose_port_watch_rtnl(event, rtnl_socket_pair[0], on_address_change, &exposed, &rtnl);
                         if (r < 0)
                                 goto finish;
 
-                        (void) expose_ports(rtnl, &exposed);
+                        (void) expose_port_execute(rtnl, arg_expose_ports, &exposed);
                 }
 
                 rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]);
@@ -5583,7 +3546,8 @@ int main(int argc, char *argv[]) {
                         putc('\n', stdout);
 
                 /* Kill if it is not dead yet anyway */
-                terminate_machine(pid);
+                if (arg_register && !arg_keep_unit)
+                        terminate_machine(pid);
 
                 /* Normally redundant, but better safe than sorry */
                 kill(pid, SIGKILL);
@@ -5621,7 +3585,7 @@ int main(int argc, char *argv[]) {
                         break;
                 }
 
-                flush_ports(&exposed);
+                expose_port_flush(arg_expose_ports, &exposed);
         }
 
 finish:
@@ -5653,7 +3617,7 @@ finish:
                 (void) rm_rf(p, REMOVE_ROOT);
         }
 
-        flush_ports(&exposed);
+        expose_port_flush(arg_expose_ports, &exposed);
 
         free(arg_directory);
         free(arg_template);