diff options
Diffstat (limited to 'src/systemd-nspawn')
23 files changed, 8405 insertions, 0 deletions
diff --git a/src/systemd-nspawn/.gitignore b/src/systemd-nspawn/.gitignore new file mode 100644 index 0000000000..85c81fff24 --- /dev/null +++ b/src/systemd-nspawn/.gitignore @@ -0,0 +1 @@ +/nspawn-gperf.c diff --git a/src/systemd-nspawn/Makefile b/src/systemd-nspawn/Makefile new file mode 100644 index 0000000000..e66a68c898 --- /dev/null +++ b/src/systemd-nspawn/Makefile @@ -0,0 +1,84 @@ +# -*- Mode: makefile; indent-tabs-mode: t -*- +# +# This file is part of systemd. +# +# Copyright 2010-2012 Lennart Poettering +# Copyright 2010-2012 Kay Sievers +# Copyright 2013 Zbigniew JÄ™drzejewski-Szmek +# Copyright 2013 David Strauss +# Copyright 2016 Luke Shumaker +# +# 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 $(dir $(lastword $(MAKEFILE_LIST)))/../../config.mk +include $(topsrcdir)/build-aux/Makefile.head.mk + +systemd_nspawn_SOURCES = \ + src/nspawn/nspawn.c \ + 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/nspawn/nspawn-stub-pid1.c \ + src/nspawn/nspawn-stub-pid1.h \ + src/nspawn/nspawn-patch-uid.c \ + src/nspawn/nspawn-patch-uid.h \ + src/core/mount-setup.c \ + src/core/mount-setup.h \ + src/core/loopback-setup.c \ + src/core/loopback-setup.h \ + src/core/machine-id-setup.c \ + src/core/machine-id-setup.h + +nodist_systemd_nspawn_SOURCES = \ + src/nspawn/nspawn-gperf.c + +gperf_gperf_sources += \ + src/nspawn/nspawn-gperf.gperf + +systemd_nspawn_CFLAGS = \ + $(AM_CFLAGS) \ + $(BLKID_CFLAGS) \ + $(SECCOMP_CFLAGS) + +systemd_nspawn_LDADD = \ + libshared.la \ + $(BLKID_LIBS) + +ifneq ($(HAVE_LIBIPTC),) +systemd_nspawn_LDADD += \ + libfirewall.la +endif # HAVE_LIBIPTC + +test_patch_uid_SOURCES = \ + src/nspawn/nspawn-patch-uid.c \ + src/nspawn/nspawn-patch-uid.h \ + src/nspawn/test-patch-uid.c + +test_patch_uid_LDADD = \ + libshared.la + +manual_tests += \ + test-patch-uid + +include $(topsrcdir)/build-aux/Makefile.tail.mk diff --git a/src/systemd-nspawn/nspawn-cgroup.c b/src/systemd-nspawn/nspawn-cgroup.c new file mode 100644 index 0000000000..f50f1ad6c2 --- /dev/null +++ b/src/systemd-nspawn/nspawn-cgroup.c @@ -0,0 +1,162 @@ +/*** + 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 "alloc-util.h" +#include "cgroup-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "mkdir.h" +#include "nspawn-cgroup.h" +#include "string-util.h" +#include "strv.h" +#include "util.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.events", + "cgroup.clone_children", + "cgroup.controllers", + "cgroup.subtree_control") + 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 hierarchy 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, "cgroup2", MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL); + 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 hierarchy 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/systemd-nspawn/nspawn-cgroup.h b/src/systemd-nspawn/nspawn-cgroup.h new file mode 100644 index 0000000000..1ff35a299a --- /dev/null +++ b/src/systemd-nspawn/nspawn-cgroup.h @@ -0,0 +1,27 @@ +#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 <stdbool.h> +#include <sys/types.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/systemd-nspawn/nspawn-expose-ports.c b/src/systemd-nspawn/nspawn-expose-ports.c new file mode 100644 index 0000000000..8122a14f7b --- /dev/null +++ b/src/systemd-nspawn/nspawn-expose-ports.c @@ -0,0 +1,245 @@ +/*** + 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 <systemd/sd-netlink.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "firewall-util.h" +#include "in-addr-util.h" +#include "local-addresses.h" +#include "netlink-util.h" +#include "nspawn-expose-ports.h" +#include "parse-util.h" +#include "socket-util.h" +#include "string-util.h" +#include "util.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) { + _cleanup_close_ int fd = -1; + int r; + + 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"); + + /* Store away the fd in the socket, so that it stays open as + * long as we run the child */ + r = send_one_fd(send_fd, fd, 0); + if (r < 0) + return log_error_errno(r, "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) { + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + int fd, r; + + assert(event); + assert(recv_fd >= 0); + assert(ret); + + fd = receive_one_fd(recv_fd, 0); + if (fd < 0) + return log_error_errno(fd, "Failed to recv netlink fd: %m"); + + 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/systemd-nspawn/nspawn-expose-ports.h b/src/systemd-nspawn/nspawn-expose-ports.h new file mode 100644 index 0000000000..0e9f8f7e88 --- /dev/null +++ b/src/systemd-nspawn/nspawn-expose-ports.h @@ -0,0 +1,44 @@ +#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 <systemd/sd-event.h> +#include <systemd/sd-netlink.h> + +#include "in-addr-util.h" +#include "list.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/systemd-nspawn/nspawn-gperf.gperf b/src/systemd-nspawn/nspawn-gperf.gperf new file mode 100644 index 0000000000..2b5d452662 --- /dev/null +++ b/src/systemd-nspawn/nspawn-gperf.gperf @@ -0,0 +1,44 @@ +%{ +#include <stddef.h> +#include "conf-parser.h" +#include "nspawn-settings.h" +#include "nspawn-expose-ports.h" +%} +struct ConfigPerfItem; +%null_strings +%language=ANSI-C +%define slot-name section_and_lvalue +%define hash-function-name nspawn_gperf_hash +%define lookup-function-name nspawn_gperf_lookup +%readonly-tables +%omit-struct-type +%struct-type +%includes +%% +Exec.Boot, config_parse_boot, 0, 0 +Exec.ProcessTwo, config_parse_pid2, 0, 0 +Exec.Parameters, config_parse_strv, 0, offsetof(Settings, parameters) +Exec.Environment, config_parse_strv, 0, offsetof(Settings, environment) +Exec.User, config_parse_string, 0, offsetof(Settings, user) +Exec.Capability, config_parse_capability, 0, offsetof(Settings, capability) +Exec.DropCapability, config_parse_capability, 0, offsetof(Settings, drop_capability) +Exec.KillSignal, config_parse_signal, 0, offsetof(Settings, kill_signal) +Exec.Personality, config_parse_personality, 0, offsetof(Settings, personality) +Exec.MachineID, config_parse_id128, 0, offsetof(Settings, machine_id) +Exec.WorkingDirectory, config_parse_path, 0, offsetof(Settings, working_directory) +Exec.PrivateUsers, config_parse_private_users, 0, 0 +Files.ReadOnly, config_parse_tristate, 0, offsetof(Settings, read_only) +Files.Volatile, config_parse_volatile_mode, 0, offsetof(Settings, volatile_mode) +Files.Bind, config_parse_bind, 0, 0 +Files.BindReadOnly, config_parse_bind, 1, 0 +Files.TemporaryFileSystem, config_parse_tmpfs, 0, 0 +Files.PrivateUsersChown, config_parse_tristate, 0, offsetof(Settings, userns_chown) +Network.Private, config_parse_tristate, 0, offsetof(Settings, private_network) +Network.Interface, config_parse_strv, 0, offsetof(Settings, network_interfaces) +Network.MACVLAN, config_parse_strv, 0, offsetof(Settings, network_macvlan) +Network.IPVLAN, config_parse_strv, 0, offsetof(Settings, network_ipvlan) +Network.VirtualEthernet, config_parse_tristate, 0, offsetof(Settings, network_veth) +Network.VirtualEthernetExtra, config_parse_veth_extra, 0, 0 +Network.Bridge, config_parse_ifname, 0, offsetof(Settings, network_bridge) +Network.Zone, config_parse_network_zone, 0, 0 +Network.Port, config_parse_expose_port, 0, 0 diff --git a/src/systemd-nspawn/nspawn-mount.c b/src/systemd-nspawn/nspawn-mount.c new file mode 100644 index 0000000000..8e2d2d543c --- /dev/null +++ b/src/systemd-nspawn/nspawn-mount.c @@ -0,0 +1,943 @@ +/*** + 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 <linux/magic.h> + +#include "alloc-util.h" +#include "cgroup-util.h" +#include "escape.h" +#include "fs-util.h" +#include "label.h" +#include "mkdir.h" +#include "mount-util.h" +#include "nspawn-mount.h" +#include "parse-util.h" +#include "path-util.h" +#include "rm-rf.h" +#include "set.h" +#include "stat-util.h" +#include "string-util.h" +#include "strv.h" +#include "user-util.h" +#include "util.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_sysfs(const char *dest) { + const char *full, *top, *x; + int r; + + top = prefix_roota(dest, "/sys"); + r = path_check_fstype(top, SYSFS_MAGIC); + if (r < 0) + return log_error_errno(r, "Failed to determine filesystem type of %s: %m", top); + /* /sys might already be mounted as sysfs by the outer child in the + * !netns case. In this case, it's all good. Don't touch it because we + * don't have the right to do so, see https://github.com/systemd/systemd/issues/1555. + */ + if (r > 0) + return 0; + + full = prefix_roota(top, "/full"); + + (void) mkdir(full, 0755); + + if (mount("sysfs", full, "sysfs", MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) < 0) + return log_error_errno(errno, "Failed to mount sysfs to %s: %m", full); + + FOREACH_STRING(x, "block", "bus", "class", "dev", "devices", "kernel") { + _cleanup_free_ char *from = NULL, *to = NULL; + + from = prefix_root(full, x); + if (!from) + return log_oom(); + + to = prefix_root(top, x); + if (!to) + return log_oom(); + + (void) mkdir(to, 0755); + + if (mount(from, to, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Failed to mount /sys/%s into place: %m", x); + + if (mount(NULL, to, NULL, MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL) < 0) + return log_error_errno(errno, "Failed to mount /sys/%s read-only: %m", x); + } + + if (umount(full) < 0) + return log_error_errno(errno, "Failed to unmount %s: %m", full); + + if (rmdir(full) < 0) + return log_error_errno(errno, "Failed to remove %s: %m", full); + + x = prefix_roota(top, "/fs/kdbus"); + (void) mkdir(x, 0755); + + if (mount(NULL, top, NULL, MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, NULL) < 0) + return log_error_errno(errno, "Failed to make %s read-only: %m", top); + + return 0; +} + +int mount_all(const char *dest, + bool use_userns, bool in_userns, + bool use_netns, + 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 in_userns; + bool use_netns; + } MountPoint; + + static const MountPoint mount_table[] = { + { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true, true, false }, + { "/proc/sys", "/proc/sys", NULL, NULL, MS_BIND, true, true, false }, /* Bind mount first */ + { NULL, "/proc/sys", NULL, NULL, MS_BIND|MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_REMOUNT, true, true, false }, /* Then, make it r/o */ + { "tmpfs", "/sys", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV, true, false, true }, + { "sysfs", "/sys", "sysfs", NULL, MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, true, false, false }, + { "tmpfs", "/dev", "tmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true, false, false }, + { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true, false, false }, + { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true, false, false }, + { "tmpfs", "/tmp", "tmpfs", "mode=1777", MS_STRICTATIME, true, false, false }, +#ifdef HAVE_SELINUX + { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL, MS_BIND, false, 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, 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 (in_userns != mount_table[k].in_userns) + continue; + + if (!use_netns && mount_table[k].use_netns) + 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, use_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); + + /* 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) + return log_error_errno(r, "Failed to create mount point %s: %m", where); + + } else { + return log_error_errno(errno, "Failed to stat %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(strempty(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"); + + (void) mkdir_p(cgroup_root, 0755); + + /* 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 = prefix_roota(dest, "/sys/fs/cgroup"); + + (void) mkdir_p(p, 0755); + + 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 = prefix_roota(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, "cgroup2", MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) < 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/systemd-nspawn/nspawn-mount.h b/src/systemd-nspawn/nspawn-mount.h new file mode 100644 index 0000000000..0daf145412 --- /dev/null +++ b/src/systemd-nspawn/nspawn-mount.h @@ -0,0 +1,69 @@ +#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 <stdbool.h> + +typedef enum VolatileMode { + VOLATILE_NO, + VOLATILE_YES, + VOLATILE_STATE, + _VOLATILE_MODE_MAX, + _VOLATILE_MODE_INVALID = -1 +} VolatileMode; + +typedef enum CustomMountType { + CUSTOM_MOUNT_BIND, + CUSTOM_MOUNT_TMPFS, + CUSTOM_MOUNT_OVERLAY, + _CUSTOM_MOUNT_TYPE_MAX, + _CUSTOM_MOUNT_TYPE_INVALID = -1 +} CustomMountType; + +typedef struct CustomMount { + CustomMountType type; + bool read_only; + char *source; /* for overlayfs this is the upper directory */ + char *destination; + char *options; + char *work_dir; + char **lower; +} CustomMount; + +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); + +int custom_mount_compare(const void *a, const void *b); + +int mount_all(const char *dest, bool use_userns, bool in_userns, bool use_netns, uid_t uid_shift, uid_t uid_range, const char *selinux_apifs_context); +int mount_sysfs(const char *dest); + +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/systemd-nspawn/nspawn-network.c b/src/systemd-nspawn/nspawn-network.c new file mode 100644 index 0000000000..7052fb5804 --- /dev/null +++ b/src/systemd-nspawn/nspawn-network.c @@ -0,0 +1,694 @@ +/*** + 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 "libudev.h" +#include <systemd/sd-id128.h> +#include <systemd/sd-netlink.h> + +#include "alloc-util.h" +#include "ether-addr-util.h" +#include "lockfile-util.h" +#include "netlink-util.h" +#include "nspawn-network.h" +#include "siphash24.h" +#include "socket-util.h" +#include "stat-util.h" +#include "string-util.h" +#include "udev-util.h" +#include "util.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 VETH_EXTRA_HOST_HASH_KEY SD_ID128_MAKE(48,c7,f6,b7,ea,9d,4c,9e,b7,28,d4,de,91,d5,bf,66) +#define VETH_EXTRA_CONTAINER_HASH_KEY SD_ID128_MAKE(af,50,17,61,ce,f9,4d,35,84,0d,2b,20,54,be,ce,59) +#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 remove_one_link(sd_netlink *rtnl, const char *name) { + _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; + int r; + + if (isempty(name)) + return 0; + + r = sd_rtnl_message_new_link(rtnl, &m, RTM_DELLINK, 0); + if (r < 0) + return log_error_errno(r, "Failed to allocate netlink message: %m"); + + r = sd_netlink_message_append_string(m, IFLA_IFNAME, name); + if (r < 0) + return log_error_errno(r, "Failed to add netlink interface name: %m"); + + r = sd_netlink_call(rtnl, m, 0, NULL); + if (r == -ENODEV) /* Already gone */ + return 0; + if (r < 0) + return log_error_errno(r, "Failed to remove interface %s: %m", name); + + return 1; +} + +static int generate_mac( + const char *machine_name, + struct ether_addr *mac, + sd_id128_t hash_key, + uint64_t idx) { + + uint64_t result; + 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. */ + result = htole64(siphash24(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 add_veth( + sd_netlink *rtnl, + pid_t pid, + const char *ifname_host, + const struct ether_addr *mac_host, + const char *ifname_container, + const struct ether_addr *mac_container) { + + _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; + int r; + + assert(rtnl); + assert(ifname_host); + assert(mac_host); + assert(ifname_container); + assert(mac_container); + + 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, ifname_host); + 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, ifname_container); + 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 (%s:%s): %m", ifname_host, ifname_container); + + return 0; +} + +int setup_veth(const char *machine_name, + pid_t pid, + char iface_name[IFNAMSIZ], + bool bridge) { + + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + struct ether_addr mac_host, mac_container; + int r, i; + + assert(machine_name); + assert(pid > 0); + assert(iface_name); + + /* 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 = add_veth(rtnl, pid, iface_name, &mac_host, "host0", &mac_container); + if (r < 0) + return r; + + 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_veth_extra( + const char *machine_name, + pid_t pid, + char **pairs) { + + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + uint64_t idx = 0; + char **a, **b; + int r; + + assert(machine_name); + assert(pid > 0); + + if (strv_isempty(pairs)) + return 0; + + r = sd_netlink_open(&rtnl); + if (r < 0) + return log_error_errno(r, "Failed to connect to netlink: %m"); + + STRV_FOREACH_PAIR(a, b, pairs) { + struct ether_addr mac_host, mac_container; + + r = generate_mac(machine_name, &mac_container, VETH_EXTRA_CONTAINER_HASH_KEY, idx); + if (r < 0) + return log_error_errno(r, "Failed to generate predictable MAC address for container side of extra veth link: %m"); + + r = generate_mac(machine_name, &mac_host, VETH_EXTRA_HOST_HASH_KEY, idx); + if (r < 0) + return log_error_errno(r, "Failed to generate predictable MAC address for container side of extra veth link: %m"); + + r = add_veth(rtnl, pid, *a, &mac_host, *b, &mac_container); + if (r < 0) + return r; + + idx++; + } + + return 0; +} + +static int join_bridge(sd_netlink *rtnl, const char *veth_name, const char *bridge_name) { + _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; + int r, bridge_ifi; + + assert(rtnl); + assert(veth_name); + assert(bridge_name); + + bridge_ifi = (int) if_nametoindex(bridge_name); + if (bridge_ifi <= 0) + return -errno; + + r = sd_rtnl_message_new_link(rtnl, &m, RTM_SETLINK, 0); + if (r < 0) + return r; + + r = sd_rtnl_message_link_set_flags(m, IFF_UP, IFF_UP); + if (r < 0) + return r; + + r = sd_netlink_message_append_string(m, IFLA_IFNAME, veth_name); + if (r < 0) + return r; + + r = sd_netlink_message_append_u32(m, IFLA_MASTER, bridge_ifi); + if (r < 0) + return r; + + r = sd_netlink_call(rtnl, m, 0, NULL); + if (r < 0) + return r; + + return bridge_ifi; +} + +static int create_bridge(sd_netlink *rtnl, const char *bridge_name) { + _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; + int r; + + r = sd_rtnl_message_new_link(rtnl, &m, RTM_NEWLINK, 0); + if (r < 0) + return r; + + r = sd_netlink_message_append_string(m, IFLA_IFNAME, bridge_name); + if (r < 0) + return r; + + r = sd_netlink_message_open_container(m, IFLA_LINKINFO); + if (r < 0) + return r; + + r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, "bridge"); + if (r < 0) + return r; + + r = sd_netlink_message_close_container(m); + if (r < 0) + return r; + + r = sd_netlink_message_close_container(m); + if (r < 0) + return r; + + r = sd_netlink_call(rtnl, m, 0, NULL); + if (r < 0) + return r; + + return 0; +} + +int setup_bridge(const char *veth_name, const char *bridge_name, bool create) { + _cleanup_release_lock_file_ LockFile bridge_lock = LOCK_FILE_INIT; + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + int r, bridge_ifi; + unsigned n = 0; + + assert(veth_name); + assert(bridge_name); + + r = sd_netlink_open(&rtnl); + if (r < 0) + return log_error_errno(r, "Failed to connect to netlink: %m"); + + if (create) { + /* We take a system-wide lock here, so that we can safely check whether there's still a member in the + * bridge before removing it, without risking interferance from other nspawn instances. */ + + r = make_lock_file("/run/systemd/nspawn-network-zone", LOCK_EX, &bridge_lock); + if (r < 0) + return log_error_errno(r, "Failed to take network zone lock: %m"); + } + + for (;;) { + bridge_ifi = join_bridge(rtnl, veth_name, bridge_name); + if (bridge_ifi >= 0) + return bridge_ifi; + if (bridge_ifi != -ENODEV || !create || n > 10) + return log_error_errno(bridge_ifi, "Failed to add interface %s to bridge %s: %m", veth_name, bridge_name); + + /* Count attempts, so that we don't enter an endless loop here. */ + n++; + + /* The bridge doesn't exist yet. Let's create it */ + r = create_bridge(rtnl, bridge_name); + if (r < 0) + return log_error_errno(r, "Failed to create bridge interface %s: %m", bridge_name); + + /* Try again, now that the bridge exists */ + } +} + +int remove_bridge(const char *bridge_name) { + _cleanup_release_lock_file_ LockFile bridge_lock = LOCK_FILE_INIT; + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + const char *path; + int r; + + /* Removes the specified bridge, but only if it is currently empty */ + + if (isempty(bridge_name)) + return 0; + + r = make_lock_file("/run/systemd/nspawn-network-zone", LOCK_EX, &bridge_lock); + if (r < 0) + return log_error_errno(r, "Failed to take network zone lock: %m"); + + path = strjoina("/sys/class/net/", bridge_name, "/brif"); + + r = dir_is_empty(path); + if (r == -ENOENT) /* Already gone? */ + return 0; + if (r < 0) + return log_error_errno(r, "Can't detect if bridge %s is empty: %m", bridge_name); + if (r == 0) /* Still populated, leave it around */ + return 0; + + r = sd_netlink_open(&rtnl); + if (r < 0) + return log_error_errno(r, "Failed to connect to netlink: %m"); + + return remove_one_link(rtnl, bridge_name); +} + +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_(sd_netlink_unrefp) 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_(sd_netlink_message_unrefp) 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_(sd_netlink_unrefp) 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_(sd_netlink_message_unrefp) 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_(sd_netlink_unrefp) 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_(sd_netlink_message_unrefp) 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; +} + +int veth_extra_parse(char ***l, const char *p) { + _cleanup_free_ char *a = NULL, *b = NULL; + int r; + + r = extract_first_word(&p, &a, ":", EXTRACT_DONT_COALESCE_SEPARATORS); + if (r < 0) + return r; + if (r == 0 || !ifname_valid(a)) + return -EINVAL; + + r = extract_first_word(&p, &b, ":", EXTRACT_DONT_COALESCE_SEPARATORS); + if (r < 0) + return r; + if (r == 0 || !ifname_valid(b)) { + free(b); + b = strdup(a); + if (!b) + return -ENOMEM; + } + + if (p) + return -EINVAL; + + r = strv_push_pair(l, a, b); + if (r < 0) + return -ENOMEM; + + a = b = NULL; + return 0; +} + +int remove_veth_links(const char *primary, char **pairs) { + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + char **a, **b; + int r; + + /* In some cases the kernel might pin the veth links between host and container even after the namespace + * died. Hence, let's better remove them explicitly too. */ + + if (isempty(primary) && strv_isempty(pairs)) + return 0; + + r = sd_netlink_open(&rtnl); + if (r < 0) + return log_error_errno(r, "Failed to connect to netlink: %m"); + + remove_one_link(rtnl, primary); + + STRV_FOREACH_PAIR(a, b, pairs) + remove_one_link(rtnl, *a); + + return 0; +} diff --git a/src/systemd-nspawn/nspawn-network.h b/src/systemd-nspawn/nspawn-network.h new file mode 100644 index 0000000000..3d8861e1e5 --- /dev/null +++ b/src/systemd-nspawn/nspawn-network.h @@ -0,0 +1,39 @@ +#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 <stdbool.h> +#include <sys/types.h> + +int setup_veth(const char *machine_name, pid_t pid, char iface_name[IFNAMSIZ], bool bridge); +int setup_veth_extra(const char *machine_name, pid_t pid, char **pairs); + +int setup_bridge(const char *veth_name, const char *bridge_name, bool create); +int remove_bridge(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); + +int veth_extra_parse(char ***l, const char *p); + +int remove_veth_links(const char *primary, char **pairs); diff --git a/src/systemd-nspawn/nspawn-patch-uid.c b/src/systemd-nspawn/nspawn-patch-uid.c new file mode 100644 index 0000000000..c7382d412d --- /dev/null +++ b/src/systemd-nspawn/nspawn-patch-uid.c @@ -0,0 +1,469 @@ +/*** + This file is part of systemd. + + Copyright 2016 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 <fcntl.h> +#include <linux/magic.h> +#ifdef HAVE_ACL +#include <sys/acl.h> +#endif +#include <sys/stat.h> +#include <sys/vfs.h> +#include <unistd.h> + +#include "acl-util.h" +#include "dirent-util.h" +#include "fd-util.h" +#include "missing.h" +#include "nspawn-patch-uid.h" +#include "stat-util.h" +#include "stdio-util.h" +#include "string-util.h" +#include "strv.h" +#include "user-util.h" + +#ifdef HAVE_ACL + +static int get_acl(int fd, const char *name, acl_type_t type, acl_t *ret) { + char procfs_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int) + 1]; + acl_t acl; + + assert(fd >= 0); + assert(ret); + + if (name) { + _cleanup_close_ int child_fd = -1; + + child_fd = openat(fd, name, O_PATH|O_CLOEXEC|O_NOFOLLOW); + if (child_fd < 0) + return -errno; + + xsprintf(procfs_path, "/proc/self/fd/%i", child_fd); + acl = acl_get_file(procfs_path, type); + } else if (type == ACL_TYPE_ACCESS) + acl = acl_get_fd(fd); + else { + xsprintf(procfs_path, "/proc/self/fd/%i", fd); + acl = acl_get_file(procfs_path, type); + } + if (!acl) + return -errno; + + *ret = acl; + return 0; +} + +static int set_acl(int fd, const char *name, acl_type_t type, acl_t acl) { + char procfs_path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int) + 1]; + int r; + + assert(fd >= 0); + assert(acl); + + if (name) { + _cleanup_close_ int child_fd = -1; + + child_fd = openat(fd, name, O_PATH|O_CLOEXEC|O_NOFOLLOW); + if (child_fd < 0) + return -errno; + + xsprintf(procfs_path, "/proc/self/fd/%i", child_fd); + r = acl_set_file(procfs_path, type, acl); + } else if (type == ACL_TYPE_ACCESS) + r = acl_set_fd(fd, acl); + else { + xsprintf(procfs_path, "/proc/self/fd/%i", fd); + r = acl_set_file(procfs_path, type, acl); + } + if (r < 0) + return -errno; + + return 0; +} + +static int shift_acl(acl_t acl, uid_t shift, acl_t *ret) { + _cleanup_(acl_freep) acl_t copy = NULL; + acl_entry_t i; + int r; + + assert(acl); + assert(ret); + + r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i); + if (r < 0) + return -errno; + while (r > 0) { + uid_t *old_uid, new_uid; + bool modify = false; + acl_tag_t tag; + + if (acl_get_tag_type(i, &tag) < 0) + return -errno; + + if (IN_SET(tag, ACL_USER, ACL_GROUP)) { + + /* We don't distuingish here between uid_t and gid_t, let's make sure the compiler checks that + * this is actually OK */ + assert_cc(sizeof(uid_t) == sizeof(gid_t)); + + old_uid = acl_get_qualifier(i); + if (!old_uid) + return -errno; + + new_uid = shift | (*old_uid & UINT32_C(0xFFFF)); + if (!uid_is_valid(new_uid)) + return -EINVAL; + + modify = new_uid != *old_uid; + if (modify && !copy) { + int n; + + /* There's no copy of the ACL yet? if so, let's create one, and start the loop from the + * beginning, so that we copy all entries, starting from the first, this time. */ + + n = acl_entries(acl); + if (n < 0) + return -errno; + + copy = acl_init(n); + if (!copy) + return -errno; + + /* Seek back to the beginning */ + r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i); + if (r < 0) + return -errno; + continue; + } + } + + if (copy) { + acl_entry_t new_entry; + + if (acl_create_entry(©, &new_entry) < 0) + return -errno; + + if (acl_copy_entry(new_entry, i) < 0) + return -errno; + + if (modify) + if (acl_set_qualifier(new_entry, &new_uid) < 0) + return -errno; + } + + r = acl_get_entry(acl, ACL_NEXT_ENTRY, &i); + if (r < 0) + return -errno; + } + + *ret = copy; + copy = NULL; + + return !!*ret; +} + +static int patch_acls(int fd, const char *name, const struct stat *st, uid_t shift) { + _cleanup_(acl_freep) acl_t acl = NULL, shifted = NULL; + bool changed = false; + int r; + + assert(fd >= 0); + assert(st); + + /* ACLs are not supported on symlinks, there's no point in trying */ + if (S_ISLNK(st->st_mode)) + return 0; + + r = get_acl(fd, name, ACL_TYPE_ACCESS, &acl); + if (r == -EOPNOTSUPP) + return 0; + if (r < 0) + return r; + + r = shift_acl(acl, shift, &shifted); + if (r < 0) + return r; + if (r > 0) { + r = set_acl(fd, name, ACL_TYPE_ACCESS, shifted); + if (r < 0) + return r; + + changed = true; + } + + if (S_ISDIR(st->st_mode)) { + acl_free(acl); + acl_free(shifted); + + acl = shifted = NULL; + + r = get_acl(fd, name, ACL_TYPE_DEFAULT, &acl); + if (r < 0) + return r; + + r = shift_acl(acl, shift, &shifted); + if (r < 0) + return r; + if (r > 0) { + r = set_acl(fd, name, ACL_TYPE_DEFAULT, shifted); + if (r < 0) + return r; + + changed = true; + } + } + + return changed; +} + +#else + +static int patch_acls(int fd, const char *name, const struct stat *st, uid_t shift) { + return 0; +} + +#endif + +static int patch_fd(int fd, const char *name, const struct stat *st, uid_t shift) { + uid_t new_uid; + gid_t new_gid; + bool changed = false; + int r; + + assert(fd >= 0); + assert(st); + + new_uid = shift | (st->st_uid & UINT32_C(0xFFFF)); + new_gid = (gid_t) shift | (st->st_gid & UINT32_C(0xFFFF)); + + if (!uid_is_valid(new_uid) || !gid_is_valid(new_gid)) + return -EINVAL; + + if (st->st_uid != new_uid || st->st_gid != new_gid) { + if (name) + r = fchownat(fd, name, new_uid, new_gid, AT_SYMLINK_NOFOLLOW); + else + r = fchown(fd, new_uid, new_gid); + if (r < 0) + return -errno; + + /* The Linux kernel alters the mode in some cases of chown(). Let's undo this. */ + if (name && !S_ISLNK(st->st_mode)) + r = fchmodat(fd, name, st->st_mode, 0); + else + r = fchmod(fd, st->st_mode); + if (r < 0) + return -errno; + + changed = true; + } + + r = patch_acls(fd, name, st, shift); + if (r < 0) + return r; + + return r > 0 || changed; +} + +static int is_procfs_sysfs_or_suchlike(int fd) { + struct statfs sfs; + + assert(fd >= 0); + + if (fstatfs(fd, &sfs) < 0) + return -errno; + + return F_TYPE_EQUAL(sfs.f_type, BINFMTFS_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, CGROUP_SUPER_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, CGROUP2_SUPER_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, DEBUGFS_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, DEVPTS_SUPER_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, EFIVARFS_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, HUGETLBFS_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, MQUEUE_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, PROC_SUPER_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, PSTOREFS_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, SELINUX_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, SMACK_MAGIC) || + F_TYPE_EQUAL(sfs.f_type, SYSFS_MAGIC); +} + +static int recurse_fd(int fd, bool donate_fd, const struct stat *st, uid_t shift, bool is_toplevel) { + bool changed = false; + int r; + + assert(fd >= 0); + + /* We generally want to permit crossing of mount boundaries when patching the UIDs/GIDs. However, we + * probably shouldn't do this for /proc and /sys if that is already mounted into place. Hence, let's + * stop the recursion when we hit a procfs or sysfs file system. */ + r = is_procfs_sysfs_or_suchlike(fd); + if (r < 0) + goto finish; + if (r > 0) { + r = 0; /* don't recurse */ + goto finish; + } + + r = patch_fd(fd, NULL, st, shift); + if (r == -EROFS) { + _cleanup_free_ char *name = NULL; + + if (!is_toplevel) { + /* When we hit a ready-only subtree we simply skip it, but log about it. */ + (void) fd_get_path(fd, &name); + log_debug("Skippping read-only file or directory %s.", strna(name)); + r = 0; + } + + goto finish; + } + if (r < 0) + goto finish; + + if (S_ISDIR(st->st_mode)) { + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + + if (!donate_fd) { + int copy; + + copy = fcntl(fd, F_DUPFD_CLOEXEC, 3); + if (copy < 0) { + r = -errno; + goto finish; + } + + fd = copy; + donate_fd = true; + } + + d = fdopendir(fd); + if (!d) { + r = -errno; + goto finish; + } + fd = -1; + + FOREACH_DIRENT_ALL(de, d, r = -errno; goto finish) { + struct stat fst; + + if (STR_IN_SET(de->d_name, ".", "..")) + continue; + + if (fstatat(dirfd(d), de->d_name, &fst, AT_SYMLINK_NOFOLLOW) < 0) { + r = -errno; + goto finish; + } + + if (S_ISDIR(fst.st_mode)) { + int subdir_fd; + + subdir_fd = openat(dirfd(d), de->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME); + if (subdir_fd < 0) { + r = -errno; + goto finish; + + } + + r = recurse_fd(subdir_fd, true, &fst, shift, false); + if (r < 0) + goto finish; + if (r > 0) + changed = true; + + } else { + r = patch_fd(dirfd(d), de->d_name, &fst, shift); + if (r < 0) + goto finish; + if (r > 0) + changed = true; + } + } + } + + r = changed; + +finish: + if (donate_fd) + safe_close(fd); + + return r; +} + +static int fd_patch_uid_internal(int fd, bool donate_fd, uid_t shift, uid_t range) { + struct stat st; + int r; + + assert(fd >= 0); + + /* Recursively adjusts the UID/GIDs of all files of a directory tree. This is used to automatically fix up an + * OS tree to the used user namespace UID range. Note that this automatic adjustment only works for UID ranges + * following the concept that the upper 16bit of a UID identify the container, and the lower 16bit are the actual + * UID within the container. */ + + if ((shift & 0xFFFF) != 0) { + /* We only support containers where the shift starts at a 2^16 boundary */ + r = -EOPNOTSUPP; + goto finish; + } + + if (range != 0x10000) { + /* We only support containers with 16bit UID ranges for the patching logic */ + r = -EOPNOTSUPP; + goto finish; + } + + if (fstat(fd, &st) < 0) { + r = -errno; + goto finish; + } + + if ((uint32_t) st.st_uid >> 16 != (uint32_t) st.st_gid >> 16) { + /* We only support containers where the uid/gid container ID match */ + r = -EBADE; + goto finish; + } + + /* Try to detect if the range is already right. Of course, this a pretty drastic optimization, as we assume + * that if the top-level dir has the right upper 16bit assigned, then everything below will have too... */ + if (((uint32_t) (st.st_uid ^ shift) >> 16) == 0) + return 0; + + return recurse_fd(fd, donate_fd, &st, shift, true); + +finish: + if (donate_fd) + safe_close(fd); + + return r; +} + +int fd_patch_uid(int fd, uid_t shift, uid_t range) { + return fd_patch_uid_internal(fd, false, shift, range); +} + +int path_patch_uid(const char *path, uid_t shift, uid_t range) { + int fd; + + fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME); + if (fd < 0) + return -errno; + + return fd_patch_uid_internal(fd, true, shift, range); +} diff --git a/src/systemd-nspawn/nspawn-patch-uid.h b/src/systemd-nspawn/nspawn-patch-uid.h new file mode 100644 index 0000000000..55d0990016 --- /dev/null +++ b/src/systemd-nspawn/nspawn-patch-uid.h @@ -0,0 +1,23 @@ +/*** + This file is part of systemd. + + Copyright 2016 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> + +int fd_patch_uid(int fd, uid_t shift, uid_t range); +int path_patch_uid(const char *path, uid_t shift, uid_t range); diff --git a/src/systemd-nspawn/nspawn-register.c b/src/systemd-nspawn/nspawn-register.c new file mode 100644 index 0000000000..adef200cb5 --- /dev/null +++ b/src/systemd-nspawn/nspawn-register.c @@ -0,0 +1,236 @@ +/*** + 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 <systemd/sd-bus.h> + +#include "bus-error.h" +#include "bus-unit-util.h" +#include "bus-util.h" +#include "nspawn-register.h" +#include "stat-util.h" +#include "strv.h" +#include "util.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, + const char *service) { + + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + _cleanup_(sd_bus_flush_close_unrefp) 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), + service, + "container", + (uint32_t) pid, + strempty(directory), + local_ifindex > 0 ? 1 : 0, local_ifindex); + } else { + _cleanup_(sd_bus_message_unrefp) 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), + service, + "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 = 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_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_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL; + _cleanup_(sd_bus_flush_close_unrefp) 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/systemd-nspawn/nspawn-register.h b/src/systemd-nspawn/nspawn-register.h new file mode 100644 index 0000000000..c7a50f7477 --- /dev/null +++ b/src/systemd-nspawn/nspawn-register.h @@ -0,0 +1,29 @@ +#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 <systemd/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, const char *service); +int terminate_machine(pid_t pid); diff --git a/src/systemd-nspawn/nspawn-settings.c b/src/systemd-nspawn/nspawn-settings.c new file mode 100644 index 0000000000..5f1522cfb6 --- /dev/null +++ b/src/systemd-nspawn/nspawn-settings.c @@ -0,0 +1,516 @@ +/*** + 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 "alloc-util.h" +#include "cap-list.h" +#include "conf-parser.h" +#include "nspawn-network.h" +#include "nspawn-settings.h" +#include "parse-util.h" +#include "process-util.h" +#include "socket-util.h" +#include "string-util.h" +#include "strv.h" +#include "user-util.h" +#include "util.h" + +int settings_load(FILE *f, const char *path, Settings **ret) { + _cleanup_(settings_freep) Settings *s = NULL; + int r; + + assert(path); + assert(ret); + + s = new0(Settings, 1); + if (!s) + return -ENOMEM; + + s->start_mode = _START_MODE_INVALID; + s->personality = PERSONALITY_INVALID; + s->userns_mode = _USER_NAMESPACE_MODE_INVALID; + s->uid_shift = UID_INVALID; + s->uid_range = UID_INVALID; + + s->read_only = -1; + s->volatile_mode = _VOLATILE_MODE_INVALID; + s->userns_chown = -1; + + s->private_network = -1; + s->network_veth = -1; + + r = config_parse(NULL, path, f, + "Exec\0" + "Network\0" + "Files\0", + config_item_perf_lookup, nspawn_gperf_lookup, + false, + false, + true, + s); + if (r < 0) + return r; + + /* Make sure that if userns_mode is set, userns_chown is set to something appropriate, and vice versa. Either + * both fields shall be initialized or neither. */ + if (s->userns_mode == USER_NAMESPACE_PICK) + s->userns_chown = true; + else if (s->userns_mode != _USER_NAMESPACE_MODE_INVALID && s->userns_chown < 0) + s->userns_chown = false; + + if (s->userns_chown >= 0 && s->userns_mode == _USER_NAMESPACE_MODE_INVALID) + s->userns_mode = USER_NAMESPACE_NO; + + *ret = s; + s = NULL; + + return 0; +} + +Settings* settings_free(Settings *s) { + + if (!s) + return NULL; + + strv_free(s->parameters); + strv_free(s->environment); + free(s->user); + free(s->working_directory); + + strv_free(s->network_interfaces); + strv_free(s->network_macvlan); + strv_free(s->network_ipvlan); + strv_free(s->network_veth_extra); + free(s->network_bridge); + free(s->network_zone); + expose_port_free_all(s->expose_ports); + + custom_mount_free_all(s->custom_mounts, s->n_custom_mounts); + free(s); + + return NULL; +} + +bool settings_private_network(Settings *s) { + assert(s); + + return + s->private_network > 0 || + s->network_veth > 0 || + s->network_bridge || + s->network_zone || + s->network_interfaces || + s->network_macvlan || + s->network_ipvlan || + s->network_veth_extra; +} + +bool settings_network_veth(Settings *s) { + assert(s); + + return + s->network_veth > 0 || + s->network_bridge || + s->network_zone; +} + +DEFINE_CONFIG_PARSE_ENUM(config_parse_volatile_mode, volatile_mode, VolatileMode, "Failed to parse volatile mode"); + +int config_parse_expose_port( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *s = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = expose_port_parse(&s->expose_ports, rvalue); + if (r == -EEXIST) { + log_syntax(unit, LOG_ERR, filename, line, r, "Duplicate port specification, ignoring: %s", rvalue); + return 0; + } + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse host port %s: %m", rvalue); + return 0; + } + + return 0; +} + +int config_parse_capability( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + uint64_t u = 0, *result = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + for (;;) { + _cleanup_free_ char *word = NULL; + int cap; + + r = extract_first_word(&rvalue, &word, NULL, 0); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Failed to extract capability string, ignoring: %s", rvalue); + return 0; + } + if (r == 0) + break; + + cap = capability_from_name(word); + if (cap < 0) { + log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse capability, ignoring: %s", word); + continue; + } + + u |= 1 << ((uint64_t) cap); + } + + if (u == 0) + return 0; + + *result |= u; + return 0; +} + +int config_parse_id128( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + sd_id128_t t, *result = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = sd_id128_from_string(rvalue, &t); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse 128bit ID/UUID, ignoring: %s", rvalue); + return 0; + } + + *result = t; + return 0; +} + +int config_parse_bind( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = bind_mount_parse(&settings->custom_mounts, &settings->n_custom_mounts, rvalue, ltype); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Invalid bind mount specification %s: %m", rvalue); + return 0; + } + + return 0; +} + +int config_parse_tmpfs( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = tmpfs_mount_parse(&settings->custom_mounts, &settings->n_custom_mounts, rvalue); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Invalid temporary file system specification %s: %m", rvalue); + return 0; + } + + return 0; +} + +int config_parse_veth_extra( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = veth_extra_parse(&settings->network_veth_extra, rvalue); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Invalid extra virtual Ethernet link specification %s: %m", rvalue); + return 0; + } + + return 0; +} + +int config_parse_network_zone( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + _cleanup_free_ char *j = NULL; + + assert(filename); + assert(lvalue); + assert(rvalue); + + j = strappend("vz-", rvalue); + if (!ifname_valid(j)) { + log_syntax(unit, LOG_ERR, filename, line, 0, "Invalid network zone name %s, ignoring: %m", rvalue); + return 0; + } + + free(settings->network_zone); + settings->network_zone = j; + j = NULL; + + return 0; +} + +int config_parse_boot( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = parse_boolean(rvalue); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse Boot= parameter %s, ignoring: %m", rvalue); + return 0; + } + + if (r > 0) { + if (settings->start_mode == START_PID2) + goto conflict; + + settings->start_mode = START_BOOT; + } else { + if (settings->start_mode == START_BOOT) + goto conflict; + + if (settings->start_mode < 0) + settings->start_mode = START_PID1; + } + + return 0; + +conflict: + log_syntax(unit, LOG_ERR, filename, line, r, "Conflicting Boot= or ProcessTwo= setting found. Ignoring."); + return 0; +} + +int config_parse_pid2( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = parse_boolean(rvalue); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse ProcessTwo= parameter %s, ignoring: %m", rvalue); + return 0; + } + + if (r > 0) { + if (settings->start_mode == START_BOOT) + goto conflict; + + settings->start_mode = START_PID2; + } else { + if (settings->start_mode == START_PID2) + goto conflict; + + if (settings->start_mode < 0) + settings->start_mode = START_PID1; + } + + return 0; + +conflict: + log_syntax(unit, LOG_ERR, filename, line, r, "Conflicting Boot= or ProcessTwo= setting found. Ignoring."); + return 0; +} + +int config_parse_private_users( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + Settings *settings = data; + int r; + + assert(filename); + assert(lvalue); + assert(rvalue); + + r = parse_boolean(rvalue); + if (r == 0) { + /* no: User namespacing off */ + settings->userns_mode = USER_NAMESPACE_NO; + settings->uid_shift = UID_INVALID; + settings->uid_range = UINT32_C(0x10000); + } else if (r > 0) { + /* yes: User namespacing on, UID range is read from root dir */ + settings->userns_mode = USER_NAMESPACE_FIXED; + settings->uid_shift = UID_INVALID; + settings->uid_range = UINT32_C(0x10000); + } else if (streq(rvalue, "pick")) { + /* pick: User namespacing on, UID range is picked randomly */ + settings->userns_mode = USER_NAMESPACE_PICK; + settings->uid_shift = UID_INVALID; + settings->uid_range = UINT32_C(0x10000); + } else { + const char *range, *shift; + uid_t sh, rn; + + /* anything else: User namespacing on, UID range is explicitly configured */ + + range = strchr(rvalue, ':'); + if (range) { + shift = strndupa(rvalue, range - rvalue); + range++; + + r = safe_atou32(range, &rn); + if (r < 0 || rn <= 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "UID/GID range invalid, ignoring: %s", range); + return 0; + } + } else { + shift = rvalue; + rn = UINT32_C(0x10000); + } + + r = parse_uid(shift, &sh); + if (r < 0) { + log_syntax(unit, LOG_ERR, filename, line, r, "UID/GID shift invalid, ignoring: %s", range); + return 0; + } + + settings->userns_mode = USER_NAMESPACE_FIXED; + settings->uid_shift = sh; + settings->uid_range = rn; + } + + return 0; +} diff --git a/src/systemd-nspawn/nspawn-settings.h b/src/systemd-nspawn/nspawn-settings.h new file mode 100644 index 0000000000..1c47e37912 --- /dev/null +++ b/src/systemd-nspawn/nspawn-settings.h @@ -0,0 +1,116 @@ +#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 <stdio.h> + +#include "macro.h" +#include "nspawn-expose-ports.h" +#include "nspawn-mount.h" + +typedef enum StartMode { + START_PID1, /* Run parameters as command line as process 1 */ + START_PID2, /* Use stub init process as PID 1, run parameters as command line as process 2 */ + START_BOOT, /* Search for init system, pass arguments as parameters */ + _START_MODE_MAX, + _START_MODE_INVALID = -1 +} StartMode; + +typedef enum UserNamespaceMode { + USER_NAMESPACE_NO, + USER_NAMESPACE_FIXED, + USER_NAMESPACE_PICK, + _USER_NAMESPACE_MODE_MAX, + _USER_NAMESPACE_MODE_INVALID = -1, +} UserNamespaceMode; + +typedef enum SettingsMask { + SETTING_START_MODE = 1 << 0, + SETTING_ENVIRONMENT = 1 << 1, + SETTING_USER = 1 << 2, + SETTING_CAPABILITY = 1 << 3, + SETTING_KILL_SIGNAL = 1 << 4, + SETTING_PERSONALITY = 1 << 5, + SETTING_MACHINE_ID = 1 << 6, + SETTING_NETWORK = 1 << 7, + SETTING_EXPOSE_PORTS = 1 << 8, + SETTING_READ_ONLY = 1 << 9, + SETTING_VOLATILE_MODE = 1 << 10, + SETTING_CUSTOM_MOUNTS = 1 << 11, + SETTING_WORKING_DIRECTORY = 1 << 12, + SETTING_USERNS = 1 << 13, + _SETTINGS_MASK_ALL = (1 << 14) -1 +} SettingsMask; + +typedef struct Settings { + /* [Run] */ + StartMode start_mode; + char **parameters; + char **environment; + char *user; + uint64_t capability; + uint64_t drop_capability; + int kill_signal; + unsigned long personality; + sd_id128_t machine_id; + char *working_directory; + UserNamespaceMode userns_mode; + uid_t uid_shift, uid_range; + + /* [Image] */ + int read_only; + VolatileMode volatile_mode; + CustomMount *custom_mounts; + unsigned n_custom_mounts; + int userns_chown; + + /* [Network] */ + int private_network; + int network_veth; + char *network_bridge; + char *network_zone; + char **network_interfaces; + char **network_macvlan; + char **network_ipvlan; + char **network_veth_extra; + ExposePort *expose_ports; +} Settings; + +int settings_load(FILE *f, const char *path, Settings **ret); +Settings* settings_free(Settings *s); + +bool settings_network_veth(Settings *s); +bool settings_private_network(Settings *s); + +DEFINE_TRIVIAL_CLEANUP_FUNC(Settings*, settings_free); + +const struct ConfigPerfItem* nspawn_gperf_lookup(const char *key, unsigned length); + +int config_parse_capability(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_id128(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_expose_port(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_volatile_mode(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_bind(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_tmpfs(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_veth_extra(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_network_zone(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_boot(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_pid2(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); +int config_parse_private_users(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata); diff --git a/src/systemd-nspawn/nspawn-setuid.c b/src/systemd-nspawn/nspawn-setuid.c new file mode 100644 index 0000000000..ee15a47e93 --- /dev/null +++ b/src/systemd-nspawn/nspawn-setuid.c @@ -0,0 +1,273 @@ +/*** + 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 <grp.h> +#include <sys/types.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "mkdir.h" +#include "nspawn-setuid.h" +#include "process-util.h" +#include "signal-util.h" +#include "string-util.h" +#include "user-util.h" +#include "util.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, "setresgid() failed: %m"); + + if (setresuid(uid, uid, uid) < 0) + return log_error_errno(errno, "setresuid() failed: %m"); + + if (_home) { + *_home = home; + home = NULL; + } + + return 0; +} diff --git a/src/systemd-nspawn/nspawn-setuid.h b/src/systemd-nspawn/nspawn-setuid.h new file mode 100644 index 0000000000..b4968ba1fc --- /dev/null +++ b/src/systemd-nspawn/nspawn-setuid.h @@ -0,0 +1,22 @@ +#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/systemd-nspawn/nspawn-stub-pid1.c b/src/systemd-nspawn/nspawn-stub-pid1.c new file mode 100644 index 0000000000..2de87e3c63 --- /dev/null +++ b/src/systemd-nspawn/nspawn-stub-pid1.c @@ -0,0 +1,170 @@ +/*** + This file is part of systemd. + + Copyright 2016 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/reboot.h> +#include <sys/unistd.h> +#include <sys/wait.h> + +#include "fd-util.h" +#include "log.h" +#include "nspawn-stub-pid1.h" +#include "process-util.h" +#include "signal-util.h" +#include "time-util.h" +#include "def.h" + +int stub_pid1(void) { + enum { + STATE_RUNNING, + STATE_REBOOT, + STATE_POWEROFF, + } state = STATE_RUNNING; + + sigset_t fullmask, oldmask, waitmask; + usec_t quit_usec = USEC_INFINITY; + pid_t pid; + int r; + + /* Implements a stub PID 1, that reaps all processes and processes a couple of standard signals. This is useful + * for allowing arbitrary processes run in a container, and still have all zombies reaped. */ + + assert_se(sigfillset(&fullmask) >= 0); + assert_se(sigprocmask(SIG_BLOCK, &fullmask, &oldmask) >= 0); + + pid = fork(); + if (pid < 0) + return log_error_errno(errno, "Failed to fork child pid: %m"); + + if (pid == 0) { + /* Return in the child */ + assert_se(sigprocmask(SIG_SETMASK, &oldmask, NULL) >= 0); + setsid(); + return 0; + } + + reset_all_signal_handlers(); + + log_close(); + close_all_fds(NULL, 0); + log_open(); + + rename_process("STUBINIT"); + + assert_se(sigemptyset(&waitmask) >= 0); + assert_se(sigset_add_many(&waitmask, + SIGCHLD, /* posix: process died */ + SIGINT, /* sysv: ctrl-alt-del */ + SIGRTMIN+3, /* systemd: halt */ + SIGRTMIN+4, /* systemd: poweroff */ + SIGRTMIN+5, /* systemd: reboot */ + SIGRTMIN+6, /* systemd: kexec */ + SIGRTMIN+13, /* systemd: halt */ + SIGRTMIN+14, /* systemd: poweroff */ + SIGRTMIN+15, /* systemd: reboot */ + SIGRTMIN+16, /* systemd: kexec */ + -1) >= 0); + + /* Note that we ignore SIGTERM (sysv's reexec), SIGHUP (reload), and all other signals here, since we don't + * support reexec/reloading in this stub process. */ + + for (;;) { + siginfo_t si; + usec_t current_usec; + + si.si_pid = 0; + r = waitid(P_ALL, 0, &si, WEXITED|WNOHANG); + if (r < 0) { + r = log_error_errno(errno, "Failed to reap children: %m"); + goto finish; + } + + current_usec = now(CLOCK_MONOTONIC); + + if (si.si_pid == pid || current_usec >= quit_usec) { + + /* The child we started ourselves died or we reached a timeout. */ + + if (state == STATE_REBOOT) { /* dispatch a queued reboot */ + (void) reboot(RB_AUTOBOOT); + r = log_error_errno(errno, "Failed to reboot: %m"); + goto finish; + + } else if (state == STATE_POWEROFF) + (void) reboot(RB_POWER_OFF); /* if this fails, fall back to normal exit. */ + + if (si.si_pid == pid && si.si_code == CLD_EXITED) + r = si.si_status; /* pass on exit code */ + else + r = 255; /* signal, coredump, timeout, … */ + + goto finish; + } + if (si.si_pid != 0) + /* We reaped something. Retry until there's nothing more to reap. */ + continue; + + if (quit_usec == USEC_INFINITY) + r = sigwaitinfo(&waitmask, &si); + else { + struct timespec ts; + r = sigtimedwait(&waitmask, &si, timespec_store(&ts, quit_usec - current_usec)); + } + if (r < 0) { + if (errno == EINTR) /* strace -p attach can result in EINTR, let's handle this nicely. */ + continue; + if (errno == EAGAIN) /* timeout reached */ + continue; + + r = log_error_errno(errno, "Failed to wait for signal: %m"); + goto finish; + } + + if (si.si_signo == SIGCHLD) + continue; /* Let's reap this */ + + if (state != STATE_RUNNING) + continue; + + /* Would love to use a switch() statement here, but SIGRTMIN is actually a function call, not a + * constant… */ + + if (si.si_signo == SIGRTMIN+3 || + si.si_signo == SIGRTMIN+4 || + si.si_signo == SIGRTMIN+13 || + si.si_signo == SIGRTMIN+14) + + state = STATE_POWEROFF; + + else if (si.si_signo == SIGINT || + si.si_signo == SIGRTMIN+5 || + si.si_signo == SIGRTMIN+6 || + si.si_signo == SIGRTMIN+15 || + si.si_signo == SIGRTMIN+16) + + state = STATE_REBOOT; + else + assert_not_reached("Got unexpected signal"); + + /* (void) kill_and_sigcont(pid, SIGTERM); */ + quit_usec = now(CLOCK_MONOTONIC) + DEFAULT_TIMEOUT_USEC; + } + +finish: + _exit(r < 0 ? EXIT_FAILURE : r); +} diff --git a/src/systemd-nspawn/nspawn-stub-pid1.h b/src/systemd-nspawn/nspawn-stub-pid1.h new file mode 100644 index 0000000000..36c1aaf5dd --- /dev/null +++ b/src/systemd-nspawn/nspawn-stub-pid1.h @@ -0,0 +1,22 @@ +#pragma once + +/*** + This file is part of systemd. + + Copyright 2016 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 stub_pid1(void); diff --git a/src/systemd-nspawn/nspawn.c b/src/systemd-nspawn/nspawn.c new file mode 100644 index 0000000000..bdf054e5c6 --- /dev/null +++ b/src/systemd-nspawn/nspawn.c @@ -0,0 +1,4116 @@ +/*** + This file is part of systemd. + + Copyright 2010 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/>. +***/ + +#ifdef HAVE_BLKID +#include <blkid/blkid.h> +#endif +#include <errno.h> +#include <getopt.h> +#include <grp.h> +#include <linux/loop.h> +#include <pwd.h> +#include <sched.h> +#ifdef HAVE_SECCOMP +#include <seccomp.h> +#endif +#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 <systemd/sd-daemon.h> +#include <systemd/sd-id128.h> + +#include "alloc-util.h" +#include "barrier.h" +#include "base-filesystem.h" +#include "blkid-util.h" +#include "btrfs-util.h" +#include "cap-list.h" +#include "capability-util.h" +#include "cgroup-util.h" +#include "copy.h" +#include "dev-setup.h" +#include "env-util.h" +#include "fd-util.h" +#include "fdset.h" +#include "fileio.h" +#include "formats-util.h" +#include "fs-util.h" +#include "gpt.h" +#include "hostname-util.h" +#include "log.h" +#include "loopback-setup.h" +#include "machine-id-setup.h" +#include "machine-image.h" +#include "macro.h" +#include "missing.h" +#include "mkdir.h" +#include "mount-util.h" +#include "netlink-util.h" +#include "nspawn-cgroup.h" +#include "nspawn-expose-ports.h" +#include "nspawn-mount.h" +#include "nspawn-network.h" +#include "nspawn-patch-uid.h" +#include "nspawn-register.h" +#include "nspawn-settings.h" +#include "nspawn-setuid.h" +#include "nspawn-stub-pid1.h" +#include "parse-util.h" +#include "path-util.h" +#include "process-util.h" +#include "ptyfwd.h" +#include "random-util.h" +#include "rm-rf.h" +#ifdef HAVE_SECCOMP +#include "seccomp-util.h" +#endif +#include "selinux-util.h" +#include "signal-util.h" +#include "socket-util.h" +#include "stat-util.h" +#include "stdio-util.h" +#include "string-util.h" +#include "strv.h" +#include "terminal-util.h" +#include "udev-util.h" +#include "umask-util.h" +#include "user-util.h" +#include "util.h" + +/* Note that devpts's gid= parameter parses GIDs as signed values, hence we stay away from the upper half of the 32bit + * UID range here */ +#define UID_SHIFT_PICK_MIN ((uid_t) UINT32_C(0x00080000)) +#define UID_SHIFT_PICK_MAX ((uid_t) UINT32_C(0x6FFF0000)) + +typedef enum ContainerStatus { + CONTAINER_TERMINATED, + CONTAINER_REBOOTED +} ContainerStatus; + +typedef enum LinkJournal { + LINK_NO, + LINK_AUTO, + LINK_HOST, + LINK_GUEST +} LinkJournal; + +static char *arg_directory = NULL; +static char *arg_template = NULL; +static char *arg_chdir = NULL; +static char *arg_user = NULL; +static sd_id128_t arg_uuid = {}; +static char *arg_machine = NULL; +static const char *arg_selinux_context = NULL; +static const char *arg_selinux_apifs_context = NULL; +static const char *arg_slice = NULL; +static bool arg_private_network = false; +static bool arg_read_only = false; +static StartMode arg_start_mode = START_PID1; +static bool arg_ephemeral = false; +static LinkJournal arg_link_journal = LINK_AUTO; +static bool arg_link_journal_try = false; +static uint64_t arg_retain = + (1ULL << CAP_CHOWN) | + (1ULL << CAP_DAC_OVERRIDE) | + (1ULL << CAP_DAC_READ_SEARCH) | + (1ULL << CAP_FOWNER) | + (1ULL << CAP_FSETID) | + (1ULL << CAP_IPC_OWNER) | + (1ULL << CAP_KILL) | + (1ULL << CAP_LEASE) | + (1ULL << CAP_LINUX_IMMUTABLE) | + (1ULL << CAP_NET_BIND_SERVICE) | + (1ULL << CAP_NET_BROADCAST) | + (1ULL << CAP_NET_RAW) | + (1ULL << CAP_SETGID) | + (1ULL << CAP_SETFCAP) | + (1ULL << CAP_SETPCAP) | + (1ULL << CAP_SETUID) | + (1ULL << CAP_SYS_ADMIN) | + (1ULL << CAP_SYS_CHROOT) | + (1ULL << CAP_SYS_NICE) | + (1ULL << CAP_SYS_PTRACE) | + (1ULL << CAP_SYS_TTY_CONFIG) | + (1ULL << CAP_SYS_RESOURCE) | + (1ULL << CAP_SYS_BOOT) | + (1ULL << CAP_AUDIT_WRITE) | + (1ULL << CAP_AUDIT_CONTROL) | + (1ULL << CAP_MKNOD); +static CustomMount *arg_custom_mounts = NULL; +static unsigned arg_n_custom_mounts = 0; +static char **arg_setenv = NULL; +static bool arg_quiet = false; +static bool arg_share_system = false; +static bool arg_register = true; +static bool arg_keep_unit = false; +static char **arg_network_interfaces = NULL; +static char **arg_network_macvlan = NULL; +static char **arg_network_ipvlan = NULL; +static bool arg_network_veth = false; +static char **arg_network_veth_extra = NULL; +static char *arg_network_bridge = NULL; +static char *arg_network_zone = NULL; +static unsigned long arg_personality = PERSONALITY_INVALID; +static char *arg_image = NULL; +static VolatileMode arg_volatile_mode = VOLATILE_NO; +static ExposePort *arg_expose_ports = NULL; +static char **arg_property = NULL; +static UserNamespaceMode arg_userns_mode = USER_NAMESPACE_NO; +static uid_t arg_uid_shift = UID_INVALID, arg_uid_range = 0x10000U; +static bool arg_userns_chown = false; +static int arg_kill_signal = 0; +static bool arg_unified_cgroup_hierarchy = false; +static SettingsMask arg_settings_mask = 0; +static int arg_settings_trusted = -1; +static char **arg_parameters = NULL; +static const char *arg_container_service_name = "systemd-nspawn"; + +static void help(void) { + printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n" + "Spawn a minimal namespace container for debugging, testing and building.\n\n" + " -h --help Show this help\n" + " --version Print version string\n" + " -q --quiet Do not show status information\n" + " -D --directory=PATH Root directory for the container\n" + " --template=PATH Initialize root directory from template directory,\n" + " if missing\n" + " -x --ephemeral Run container with snapshot of root directory, and\n" + " remove it after exit\n" + " -i --image=PATH File system device or disk image for the container\n" + " -a --as-pid2 Maintain a stub init as PID1, invoke binary as PID2\n" + " -b --boot Boot up full system (i.e. invoke init)\n" + " --chdir=PATH Set working directory in the container\n" + " -u --user=USER Run the command under specified user or uid\n" + " -M --machine=NAME Set the machine name for the container\n" + " --uuid=UUID Set a specific machine UUID for the container\n" + " -S --slice=SLICE Place the container in the specified slice\n" + " --property=NAME=VALUE Set scope unit property\n" + " -U --private-users=pick Run within user namespace, pick UID/GID range automatically\n" + " --private-users[=UIDBASE[:NUIDS]]\n" + " Run within user namespace, user configured UID/GID range\n" + " --private-user-chown Adjust OS tree file ownership for private UID/GID range\n" + " --private-network Disable network in container\n" + " --network-interface=INTERFACE\n" + " Assign an existing network interface to the\n" + " container\n" + " --network-macvlan=INTERFACE\n" + " Create a macvlan network interface based on an\n" + " existing network interface to the container\n" + " --network-ipvlan=INTERFACE\n" + " Create a ipvlan network interface based on an\n" + " existing network interface to the container\n" + " -n --network-veth Add a virtual Ethernet connection between host\n" + " and container\n" + " --network-veth-extra=HOSTIF[:CONTAINERIF]\n" + " Add an additional virtual Ethernet link between\n" + " host and container\n" + " --network-bridge=INTERFACE\n" + " Add a virtual Ethernet connection between host\n" + " and container and add it to an existing bridge on\n" + " the host\n" + " --network-zone=NAME Add a virtual Ethernet connection to the container,\n" + " and add it to an automatically managed bridge interface\n" + " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n" + " Expose a container IP port on the host\n" + " -Z --selinux-context=SECLABEL\n" + " Set the SELinux security context to be used by\n" + " processes in the container\n" + " -L --selinux-apifs-context=SECLABEL\n" + " Set the SELinux security context to be used by\n" + " API/tmpfs file systems in the container\n" + " --capability=CAP In addition to the default, retain specified\n" + " capability\n" + " --drop-capability=CAP Drop the specified capability from the default set\n" + " --kill-signal=SIGNAL Select signal to use for shutting down PID 1\n" + " --link-journal=MODE Link up guest journal, one of no, auto, guest, \n" + " host, try-guest, try-host\n" + " -j Equivalent to --link-journal=try-guest\n" + " --read-only Mount the root directory read-only\n" + " --bind=PATH[:PATH[:OPTIONS]]\n" + " Bind mount a file or directory from the host into\n" + " the container\n" + " --bind-ro=PATH[:PATH[:OPTIONS]\n" + " Similar, but creates a read-only bind mount\n" + " --tmpfs=PATH:[OPTIONS] Mount an empty tmpfs to the specified directory\n" + " --overlay=PATH[:PATH...]:PATH\n" + " Create an overlay mount from the host to \n" + " the container\n" + " --overlay-ro=PATH[:PATH...]:PATH\n" + " Similar, but creates a read-only overlay mount\n" + " -E --setenv=NAME=VALUE Pass an environment variable to PID 1\n" + " --share-system Share system namespaces with host\n" + " --register=BOOLEAN Register container as machine\n" + " --keep-unit Do not register a scope for the machine, reuse\n" + " the service unit nspawn is running in\n" + " --volatile[=MODE] Run the system in volatile mode\n" + " --settings=BOOLEAN Load additional settings from .nspawn file\n" + , program_invocation_short_name); +} + + +static int custom_mounts_prepare(void) { + unsigned i; + int r; + + /* Ensure the mounts are applied prefix first. */ + qsort_safe(arg_custom_mounts, arg_n_custom_mounts, sizeof(CustomMount), custom_mount_compare); + + /* Allocate working directories for the overlay file systems that need it */ + for (i = 0; i < arg_n_custom_mounts; i++) { + CustomMount *m = &arg_custom_mounts[i]; + + if (path_equal(m->destination, "/") && arg_userns_mode != USER_NAMESPACE_NO) { + + if (arg_userns_chown) { + log_error("--private-users-chown may not be combined with custom root mounts."); + return -EINVAL; + } else if (arg_uid_shift == UID_INVALID) { + log_error("--private-users with automatic UID shift may not be combined with custom root mounts."); + return -EINVAL; + } + } + + if (m->type != CUSTOM_MOUNT_OVERLAY) + continue; + + if (m->work_dir) + continue; + + if (m->read_only) + continue; + + r = tempfn_random(m->source, NULL, &m->work_dir); + if (r < 0) + return log_error_errno(r, "Failed to generate work directory from %s: %m", m->source); + } + + return 0; +} + +static int detect_unified_cgroup_hierarchy(void) { + const char *e; + int r; + + /* Allow the user to control whether the unified hierarchy is used */ + e = getenv("UNIFIED_CGROUP_HIERARCHY"); + if (e) { + r = parse_boolean(e); + if (r < 0) + return log_error_errno(r, "Failed to parse $UNIFIED_CGROUP_HIERARCHY."); + + arg_unified_cgroup_hierarchy = r; + return 0; + } + + /* Otherwise inherit the default from the host system */ + r = cg_unified(); + if (r < 0) + return log_error_errno(r, "Failed to determine whether the unified cgroups hierarchy is used: %m"); + + arg_unified_cgroup_hierarchy = r; + return 0; +} + +static int parse_argv(int argc, char *argv[]) { + + enum { + ARG_VERSION = 0x100, + ARG_PRIVATE_NETWORK, + ARG_UUID, + ARG_READ_ONLY, + ARG_CAPABILITY, + ARG_DROP_CAPABILITY, + ARG_LINK_JOURNAL, + ARG_BIND, + ARG_BIND_RO, + ARG_TMPFS, + ARG_OVERLAY, + ARG_OVERLAY_RO, + ARG_SHARE_SYSTEM, + ARG_REGISTER, + ARG_KEEP_UNIT, + ARG_NETWORK_INTERFACE, + ARG_NETWORK_MACVLAN, + ARG_NETWORK_IPVLAN, + ARG_NETWORK_BRIDGE, + ARG_NETWORK_ZONE, + ARG_NETWORK_VETH_EXTRA, + ARG_PERSONALITY, + ARG_VOLATILE, + ARG_TEMPLATE, + ARG_PROPERTY, + ARG_PRIVATE_USERS, + ARG_KILL_SIGNAL, + ARG_SETTINGS, + ARG_CHDIR, + ARG_PRIVATE_USERS_CHOWN, + }; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "directory", required_argument, NULL, 'D' }, + { "template", required_argument, NULL, ARG_TEMPLATE }, + { "ephemeral", no_argument, NULL, 'x' }, + { "user", required_argument, NULL, 'u' }, + { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK }, + { "as-pid2", no_argument, NULL, 'a' }, + { "boot", no_argument, NULL, 'b' }, + { "uuid", required_argument, NULL, ARG_UUID }, + { "read-only", no_argument, NULL, ARG_READ_ONLY }, + { "capability", required_argument, NULL, ARG_CAPABILITY }, + { "drop-capability", required_argument, NULL, ARG_DROP_CAPABILITY }, + { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL }, + { "bind", required_argument, NULL, ARG_BIND }, + { "bind-ro", required_argument, NULL, ARG_BIND_RO }, + { "tmpfs", required_argument, NULL, ARG_TMPFS }, + { "overlay", required_argument, NULL, ARG_OVERLAY }, + { "overlay-ro", required_argument, NULL, ARG_OVERLAY_RO }, + { "machine", required_argument, NULL, 'M' }, + { "slice", required_argument, NULL, 'S' }, + { "setenv", required_argument, NULL, 'E' }, + { "selinux-context", required_argument, NULL, 'Z' }, + { "selinux-apifs-context", required_argument, NULL, 'L' }, + { "quiet", no_argument, NULL, 'q' }, + { "share-system", no_argument, NULL, ARG_SHARE_SYSTEM }, + { "register", required_argument, NULL, ARG_REGISTER }, + { "keep-unit", no_argument, NULL, ARG_KEEP_UNIT }, + { "network-interface", required_argument, NULL, ARG_NETWORK_INTERFACE }, + { "network-macvlan", required_argument, NULL, ARG_NETWORK_MACVLAN }, + { "network-ipvlan", required_argument, NULL, ARG_NETWORK_IPVLAN }, + { "network-veth", no_argument, NULL, 'n' }, + { "network-veth-extra", required_argument, NULL, ARG_NETWORK_VETH_EXTRA}, + { "network-bridge", required_argument, NULL, ARG_NETWORK_BRIDGE }, + { "network-zone", required_argument, NULL, ARG_NETWORK_ZONE }, + { "personality", required_argument, NULL, ARG_PERSONALITY }, + { "image", required_argument, NULL, 'i' }, + { "volatile", optional_argument, NULL, ARG_VOLATILE }, + { "port", required_argument, NULL, 'p' }, + { "property", required_argument, NULL, ARG_PROPERTY }, + { "private-users", optional_argument, NULL, ARG_PRIVATE_USERS }, + { "private-users-chown", optional_argument, NULL, ARG_PRIVATE_USERS_CHOWN}, + { "kill-signal", required_argument, NULL, ARG_KILL_SIGNAL }, + { "settings", required_argument, NULL, ARG_SETTINGS }, + { "chdir", required_argument, NULL, ARG_CHDIR }, + {} + }; + + int c, r; + const char *p, *e; + uint64_t plus = 0, minus = 0; + bool mask_all_settings = false, mask_no_settings = false; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "+hD:u:abL:M:jS:Z:qi:xp:nU", options, NULL)) >= 0) + + switch (c) { + + case 'h': + help(); + return 0; + + case ARG_VERSION: + return version(); + + case 'D': + r = parse_path_argument_and_warn(optarg, false, &arg_directory); + if (r < 0) + return r; + break; + + case ARG_TEMPLATE: + r = parse_path_argument_and_warn(optarg, false, &arg_template); + if (r < 0) + return r; + break; + + case 'i': + r = parse_path_argument_and_warn(optarg, false, &arg_image); + if (r < 0) + return r; + break; + + case 'x': + arg_ephemeral = true; + break; + + case 'u': + r = free_and_strdup(&arg_user, optarg); + if (r < 0) + return log_oom(); + + arg_settings_mask |= SETTING_USER; + break; + + case ARG_NETWORK_ZONE: { + char *j; + + j = strappend("vz-", optarg); + if (!j) + return log_oom(); + + if (!ifname_valid(j)) { + log_error("Network zone name not valid: %s", j); + free(j); + return -EINVAL; + } + + free(arg_network_zone); + arg_network_zone = j; + + arg_network_veth = true; + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + } + + case ARG_NETWORK_BRIDGE: + + if (!ifname_valid(optarg)) { + log_error("Bridge interface name not valid: %s", optarg); + return -EINVAL; + } + + r = free_and_strdup(&arg_network_bridge, optarg); + if (r < 0) + return log_oom(); + + /* fall through */ + + case 'n': + arg_network_veth = true; + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + + case ARG_NETWORK_VETH_EXTRA: + r = veth_extra_parse(&arg_network_veth_extra, optarg); + if (r < 0) + return log_error_errno(r, "Failed to parse --network-veth-extra= parameter: %s", optarg); + + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + + case ARG_NETWORK_INTERFACE: + + if (!ifname_valid(optarg)) { + log_error("Network interface name not valid: %s", optarg); + return -EINVAL; + } + + if (strv_extend(&arg_network_interfaces, optarg) < 0) + return log_oom(); + + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + + case ARG_NETWORK_MACVLAN: + + if (!ifname_valid(optarg)) { + log_error("MACVLAN network interface name not valid: %s", optarg); + return -EINVAL; + } + + if (strv_extend(&arg_network_macvlan, optarg) < 0) + return log_oom(); + + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + + case ARG_NETWORK_IPVLAN: + + if (!ifname_valid(optarg)) { + log_error("IPVLAN network interface name not valid: %s", optarg); + return -EINVAL; + } + + if (strv_extend(&arg_network_ipvlan, optarg) < 0) + return log_oom(); + + /* fall through */ + + case ARG_PRIVATE_NETWORK: + arg_private_network = true; + arg_settings_mask |= SETTING_NETWORK; + break; + + case 'b': + if (arg_start_mode == START_PID2) { + log_error("--boot and --as-pid2 may not be combined."); + return -EINVAL; + } + + arg_start_mode = START_BOOT; + arg_settings_mask |= SETTING_START_MODE; + break; + + case 'a': + if (arg_start_mode == START_BOOT) { + log_error("--boot and --as-pid2 may not be combined."); + return -EINVAL; + } + + arg_start_mode = START_PID2; + arg_settings_mask |= SETTING_START_MODE; + break; + + case ARG_UUID: + r = sd_id128_from_string(optarg, &arg_uuid); + if (r < 0) { + log_error("Invalid UUID: %s", optarg); + return r; + } + + arg_settings_mask |= SETTING_MACHINE_ID; + break; + + case 'S': + arg_slice = optarg; + break; + + case 'M': + if (isempty(optarg)) + arg_machine = mfree(arg_machine); + else { + if (!machine_name_is_valid(optarg)) { + log_error("Invalid machine name: %s", optarg); + return -EINVAL; + } + + r = free_and_strdup(&arg_machine, optarg); + if (r < 0) + return log_oom(); + + break; + } + + case 'Z': + arg_selinux_context = optarg; + break; + + case 'L': + arg_selinux_apifs_context = optarg; + break; + + case ARG_READ_ONLY: + arg_read_only = true; + arg_settings_mask |= SETTING_READ_ONLY; + break; + + case ARG_CAPABILITY: + case ARG_DROP_CAPABILITY: { + p = optarg; + for (;;) { + _cleanup_free_ char *t = NULL; + + r = extract_first_word(&p, &t, ",", 0); + if (r < 0) + return log_error_errno(r, "Failed to parse capability %s.", t); + + if (r == 0) + break; + + if (streq(t, "all")) { + if (c == ARG_CAPABILITY) + plus = (uint64_t) -1; + else + minus = (uint64_t) -1; + } else { + int cap; + + cap = capability_from_name(t); + if (cap < 0) { + log_error("Failed to parse capability %s.", t); + return -EINVAL; + } + + if (c == ARG_CAPABILITY) + plus |= 1ULL << (uint64_t) cap; + else + minus |= 1ULL << (uint64_t) cap; + } + } + + arg_settings_mask |= SETTING_CAPABILITY; + break; + } + + case 'j': + arg_link_journal = LINK_GUEST; + arg_link_journal_try = true; + break; + + case ARG_LINK_JOURNAL: + if (streq(optarg, "auto")) { + arg_link_journal = LINK_AUTO; + arg_link_journal_try = false; + } else if (streq(optarg, "no")) { + arg_link_journal = LINK_NO; + arg_link_journal_try = false; + } else if (streq(optarg, "guest")) { + arg_link_journal = LINK_GUEST; + arg_link_journal_try = false; + } else if (streq(optarg, "host")) { + arg_link_journal = LINK_HOST; + arg_link_journal_try = false; + } else if (streq(optarg, "try-guest")) { + arg_link_journal = LINK_GUEST; + arg_link_journal_try = true; + } else if (streq(optarg, "try-host")) { + arg_link_journal = LINK_HOST; + arg_link_journal_try = true; + } else { + log_error("Failed to parse link journal mode %s", optarg); + return -EINVAL; + } + + break; + + case ARG_BIND: + case ARG_BIND_RO: + r = bind_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg, c == ARG_BIND_RO); + if (r < 0) + return log_error_errno(r, "Failed to parse --bind(-ro)= argument %s: %m", optarg); + + arg_settings_mask |= SETTING_CUSTOM_MOUNTS; + break; + + case ARG_TMPFS: + r = tmpfs_mount_parse(&arg_custom_mounts, &arg_n_custom_mounts, optarg); + if (r < 0) + return log_error_errno(r, "Failed to parse --tmpfs= argument %s: %m", optarg); + + arg_settings_mask |= SETTING_CUSTOM_MOUNTS; + break; + + case ARG_OVERLAY: + case ARG_OVERLAY_RO: { + _cleanup_free_ char *upper = NULL, *destination = NULL; + _cleanup_strv_free_ char **lower = NULL; + CustomMount *m; + unsigned n = 0; + char **i; + + r = strv_split_extract(&lower, optarg, ":", EXTRACT_DONT_COALESCE_SEPARATORS); + if (r == -ENOMEM) + return log_oom(); + else if (r < 0) { + log_error("Invalid overlay specification: %s", optarg); + return r; + } + + STRV_FOREACH(i, lower) { + if (!path_is_absolute(*i)) { + log_error("Overlay path %s is not absolute.", *i); + return -EINVAL; + } + + n++; + } + + if (n < 2) { + log_error("--overlay= needs at least two colon-separated directories specified."); + return -EINVAL; + } + + if (n == 2) { + /* If two parameters are specified, + * the first one is the lower, the + * second one the upper directory. And + * we'll also define the destination + * mount point the same as the upper. */ + upper = lower[1]; + lower[1] = NULL; + + destination = strdup(upper); + if (!destination) + return log_oom(); + + } else { + upper = lower[n - 2]; + destination = lower[n - 1]; + lower[n - 2] = NULL; + } + + m = custom_mount_add(&arg_custom_mounts, &arg_n_custom_mounts, CUSTOM_MOUNT_OVERLAY); + if (!m) + return log_oom(); + + m->destination = destination; + m->source = upper; + m->lower = lower; + m->read_only = c == ARG_OVERLAY_RO; + + upper = destination = NULL; + lower = NULL; + + arg_settings_mask |= SETTING_CUSTOM_MOUNTS; + break; + } + + case 'E': { + char **n; + + if (!env_assignment_is_valid(optarg)) { + log_error("Environment variable assignment '%s' is not valid.", optarg); + return -EINVAL; + } + + n = strv_env_set(arg_setenv, optarg); + if (!n) + return log_oom(); + + strv_free(arg_setenv); + arg_setenv = n; + + arg_settings_mask |= SETTING_ENVIRONMENT; + break; + } + + case 'q': + arg_quiet = true; + break; + + case ARG_SHARE_SYSTEM: + arg_share_system = true; + break; + + case ARG_REGISTER: + r = parse_boolean(optarg); + if (r < 0) { + log_error("Failed to parse --register= argument: %s", optarg); + return r; + } + + arg_register = r; + break; + + case ARG_KEEP_UNIT: + arg_keep_unit = true; + break; + + case ARG_PERSONALITY: + + arg_personality = personality_from_string(optarg); + if (arg_personality == PERSONALITY_INVALID) { + log_error("Unknown or unsupported personality '%s'.", optarg); + return -EINVAL; + } + + arg_settings_mask |= SETTING_PERSONALITY; + break; + + case ARG_VOLATILE: + + if (!optarg) + arg_volatile_mode = VOLATILE_YES; + else { + VolatileMode m; + + m = volatile_mode_from_string(optarg); + if (m < 0) { + log_error("Failed to parse --volatile= argument: %s", optarg); + return -EINVAL; + } else + arg_volatile_mode = m; + } + + arg_settings_mask |= SETTING_VOLATILE_MODE; + break; + + case 'p': + r = expose_port_parse(&arg_expose_ports, optarg); + if (r == -EEXIST) + return log_error_errno(r, "Duplicate port specification: %s", optarg); + if (r < 0) + return log_error_errno(r, "Failed to parse host port %s: %m", optarg); + + arg_settings_mask |= SETTING_EXPOSE_PORTS; + break; + + case ARG_PROPERTY: + if (strv_extend(&arg_property, optarg) < 0) + return log_oom(); + + break; + + case ARG_PRIVATE_USERS: + + r = optarg ? parse_boolean(optarg) : 1; + if (r == 0) { + /* no: User namespacing off */ + arg_userns_mode = USER_NAMESPACE_NO; + arg_uid_shift = UID_INVALID; + arg_uid_range = UINT32_C(0x10000); + } else if (r > 0) { + /* yes: User namespacing on, UID range is read from root dir */ + arg_userns_mode = USER_NAMESPACE_FIXED; + arg_uid_shift = UID_INVALID; + arg_uid_range = UINT32_C(0x10000); + } else if (streq(optarg, "pick")) { + /* pick: User namespacing on, UID range is picked randomly */ + arg_userns_mode = USER_NAMESPACE_PICK; + arg_uid_shift = UID_INVALID; + arg_uid_range = UINT32_C(0x10000); + } else { + _cleanup_free_ char *buffer = NULL; + const char *range, *shift; + + /* anything else: User namespacing on, UID range is explicitly configured */ + + range = strchr(optarg, ':'); + if (range) { + buffer = strndup(optarg, range - optarg); + if (!buffer) + return log_oom(); + shift = buffer; + + range++; + if (safe_atou32(range, &arg_uid_range) < 0 || arg_uid_range <= 0) { + log_error("Failed to parse UID range: %s", range); + return -EINVAL; + } + } else + shift = optarg; + + if (parse_uid(shift, &arg_uid_shift) < 0) { + log_error("Failed to parse UID: %s", optarg); + return -EINVAL; + } + + arg_userns_mode = USER_NAMESPACE_FIXED; + } + + arg_settings_mask |= SETTING_USERNS; + break; + + case 'U': + if (userns_supported()) { + arg_userns_mode = USER_NAMESPACE_PICK; + arg_uid_shift = UID_INVALID; + arg_uid_range = UINT32_C(0x10000); + + arg_settings_mask |= SETTING_USERNS; + } + + break; + + case ARG_PRIVATE_USERS_CHOWN: + arg_userns_chown = true; + + arg_settings_mask |= SETTING_USERNS; + break; + + case ARG_KILL_SIGNAL: + arg_kill_signal = signal_from_string_try_harder(optarg); + if (arg_kill_signal < 0) { + log_error("Cannot parse signal: %s", optarg); + return -EINVAL; + } + + arg_settings_mask |= SETTING_KILL_SIGNAL; + break; + + case ARG_SETTINGS: + + /* no → do not read files + * yes → read files, do not override cmdline, trust only subset + * override → read files, override cmdline, trust only subset + * trusted → read files, do not override cmdline, trust all + */ + + r = parse_boolean(optarg); + if (r < 0) { + if (streq(optarg, "trusted")) { + mask_all_settings = false; + mask_no_settings = false; + arg_settings_trusted = true; + + } else if (streq(optarg, "override")) { + mask_all_settings = false; + mask_no_settings = true; + arg_settings_trusted = -1; + } else + return log_error_errno(r, "Failed to parse --settings= argument: %s", optarg); + } else if (r > 0) { + /* yes */ + mask_all_settings = false; + mask_no_settings = false; + arg_settings_trusted = -1; + } else { + /* no */ + mask_all_settings = true; + mask_no_settings = false; + arg_settings_trusted = false; + } + + break; + + case ARG_CHDIR: + if (!path_is_absolute(optarg)) { + log_error("Working directory %s is not an absolute path.", optarg); + return -EINVAL; + } + + r = free_and_strdup(&arg_chdir, optarg); + if (r < 0) + return log_oom(); + + arg_settings_mask |= SETTING_WORKING_DIRECTORY; + break; + + case '?': + return -EINVAL; + + default: + assert_not_reached("Unhandled option"); + } + + if (arg_share_system) + arg_register = false; + + if (arg_userns_mode == USER_NAMESPACE_PICK) + arg_userns_chown = true; + + if (arg_start_mode != START_PID1 && arg_share_system) { + log_error("--boot and --share-system may not be combined."); + return -EINVAL; + } + + if (arg_keep_unit && cg_pid_get_owner_uid(0, NULL) >= 0) { + log_error("--keep-unit may not be used when invoked from a user session."); + return -EINVAL; + } + + if (arg_directory && arg_image) { + log_error("--directory= and --image= may not be combined."); + return -EINVAL; + } + + if (arg_template && arg_image) { + log_error("--template= and --image= may not be combined."); + return -EINVAL; + } + + if (arg_template && !(arg_directory || arg_machine)) { + log_error("--template= needs --directory= or --machine=."); + return -EINVAL; + } + + if (arg_ephemeral && arg_template) { + log_error("--ephemeral and --template= may not be combined."); + return -EINVAL; + } + + if (arg_ephemeral && arg_image) { + log_error("--ephemeral and --image= may not be combined."); + return -EINVAL; + } + + if (arg_ephemeral && !IN_SET(arg_link_journal, LINK_NO, LINK_AUTO)) { + log_error("--ephemeral and --link-journal= may not be combined."); + return -EINVAL; + } + + if (arg_userns_mode != USER_NAMESPACE_NO && !userns_supported()) { + log_error("--private-users= is not supported, kernel compiled without user namespace support."); + return -EOPNOTSUPP; + } + + if (arg_userns_chown && arg_read_only) { + log_error("--read-only and --private-users-chown may not be combined."); + return -EINVAL; + } + + if (arg_network_bridge && arg_network_zone) { + log_error("--network-bridge= and --network-zone= may not be combined."); + return -EINVAL; + } + + if (argc > optind) { + arg_parameters = strv_copy(argv + optind); + if (!arg_parameters) + return log_oom(); + + arg_settings_mask |= SETTING_START_MODE; + } + + /* Load all settings from .nspawn files */ + if (mask_no_settings) + arg_settings_mask = 0; + + /* Don't load any settings from .nspawn files */ + if (mask_all_settings) + arg_settings_mask = _SETTINGS_MASK_ALL; + + arg_retain = (arg_retain | plus | (arg_private_network ? 1ULL << CAP_NET_ADMIN : 0)) & ~minus; + + r = detect_unified_cgroup_hierarchy(); + if (r < 0) + return r; + + e = getenv("SYSTEMD_NSPAWN_CONTAINER_SERVICE"); + if (e) + arg_container_service_name = e; + + return 1; +} + +static int verify_arguments(void) { + + if (arg_volatile_mode != VOLATILE_NO && arg_read_only) { + log_error("Cannot combine --read-only with --volatile. Note that --volatile already implies a read-only base hierarchy."); + return -EINVAL; + } + + if (arg_expose_ports && !arg_private_network) { + log_error("Cannot use --port= without private networking."); + return -EINVAL; + } + +#ifndef HAVE_LIBIPTC + if (arg_expose_ports) { + log_error("--port= is not supported, compiled without libiptc support."); + return -EOPNOTSUPP; + } +#endif + + if (arg_start_mode == START_BOOT && arg_kill_signal <= 0) + arg_kill_signal = SIGRTMIN+3; + + return 0; +} + +static int userns_lchown(const char *p, uid_t uid, gid_t gid) { + assert(p); + + if (arg_userns_mode == USER_NAMESPACE_NO) + return 0; + + if (uid == UID_INVALID && gid == GID_INVALID) + return 0; + + if (uid != UID_INVALID) { + uid += arg_uid_shift; + + if (uid < arg_uid_shift || uid >= arg_uid_shift + arg_uid_range) + return -EOVERFLOW; + } + + if (gid != GID_INVALID) { + gid += (gid_t) arg_uid_shift; + + if (gid < (gid_t) arg_uid_shift || gid >= (gid_t) (arg_uid_shift + arg_uid_range)) + return -EOVERFLOW; + } + + if (lchown(p, uid, gid) < 0) + return -errno; + + return 0; +} + +static int userns_mkdir(const char *root, const char *path, mode_t mode, uid_t uid, gid_t gid) { + const char *q; + + q = prefix_roota(root, path); + if (mkdir(q, mode) < 0) { + if (errno == EEXIST) + return 0; + return -errno; + } + + return userns_lchown(q, uid, gid); +} + +static int setup_timezone(const char *dest) { + _cleanup_free_ char *p = NULL, *q = NULL; + const char *where, *check, *what; + char *z, *y; + int r; + + assert(dest); + + /* Fix the timezone, if possible */ + r = readlink_malloc("/etc/localtime", &p); + if (r < 0) { + log_warning("/etc/localtime is not a symlink, not updating container timezone."); + return 0; + } + + z = path_startswith(p, "../usr/share/zoneinfo/"); + if (!z) + z = path_startswith(p, "/usr/share/zoneinfo/"); + if (!z) { + log_warning("/etc/localtime does not point into /usr/share/zoneinfo/, not updating container timezone."); + return 0; + } + + where = prefix_roota(dest, "/etc/localtime"); + r = readlink_malloc(where, &q); + if (r >= 0) { + y = path_startswith(q, "../usr/share/zoneinfo/"); + if (!y) + y = path_startswith(q, "/usr/share/zoneinfo/"); + + /* Already pointing to the right place? Then do nothing .. */ + if (y && streq(y, z)) + return 0; + } + + check = strjoina("/usr/share/zoneinfo/", z); + check = prefix_roota(dest, check); + if (laccess(check, F_OK) < 0) { + log_warning("Timezone %s does not exist in container, not updating container timezone.", z); + return 0; + } + + r = unlink(where); + if (r < 0 && errno != ENOENT) { + log_error_errno(errno, "Failed to remove existing timezone info %s in container: %m", where); + return 0; + } + + what = strjoina("../usr/share/zoneinfo/", z); + if (symlink(what, where) < 0) { + log_error_errno(errno, "Failed to correct timezone of container: %m"); + return 0; + } + + r = userns_lchown(where, 0, 0); + if (r < 0) + return log_warning_errno(r, "Failed to chown /etc/localtime: %m"); + + return 0; +} + +static int setup_resolv_conf(const char *dest) { + const char *where = NULL; + int r; + + assert(dest); + + if (arg_private_network) + return 0; + + /* Fix resolv.conf, if possible */ + where = prefix_roota(dest, "/etc/resolv.conf"); + + r = copy_file("/etc/resolv.conf", where, O_TRUNC|O_NOFOLLOW, 0644, 0); + if (r < 0) { + /* If the file already exists as symlink, let's + * suppress the warning, under the assumption that + * resolved or something similar runs inside and the + * symlink points there. + * + * If the disk image is read-only, there's also no + * point in complaining. + */ + log_full_errno(IN_SET(r, -ELOOP, -EROFS) ? LOG_DEBUG : LOG_WARNING, r, + "Failed to copy /etc/resolv.conf to %s: %m", where); + return 0; + } + + r = userns_lchown(where, 0, 0); + if (r < 0) + log_warning_errno(r, "Failed to chown /etc/resolv.conf: %m"); + + return 0; +} + +static char* id128_format_as_uuid(sd_id128_t id, char s[37]) { + assert(s); + + snprintf(s, 37, + "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", + SD_ID128_FORMAT_VAL(id)); + + return s; +} + +static int setup_boot_id(const char *dest) { + const char *from, *to; + sd_id128_t rnd = {}; + char as_uuid[37]; + int r; + + if (arg_share_system) + return 0; + + /* Generate a new randomized boot ID, so that each boot-up of + * the container gets a new one */ + + from = prefix_roota(dest, "/run/proc-sys-kernel-random-boot-id"); + to = prefix_roota(dest, "/proc/sys/kernel/random/boot_id"); + + r = sd_id128_randomize(&rnd); + if (r < 0) + return log_error_errno(r, "Failed to generate random boot id: %m"); + + id128_format_as_uuid(rnd, as_uuid); + + r = write_string_file(from, as_uuid, WRITE_STRING_FILE_CREATE); + if (r < 0) + return log_error_errno(r, "Failed to write boot id: %m"); + + if (mount(from, to, NULL, MS_BIND, NULL) < 0) + r = log_error_errno(errno, "Failed to bind mount boot id: %m"); + else if (mount(NULL, to, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY|MS_NOSUID|MS_NODEV, NULL) < 0) + log_warning_errno(errno, "Failed to make boot id read-only: %m"); + + unlink(from); + return r; +} + +static int copy_devnodes(const char *dest) { + + static const char devnodes[] = + "null\0" + "zero\0" + "full\0" + "random\0" + "urandom\0" + "tty\0" + "net/tun\0"; + + const char *d; + int r = 0; + _cleanup_umask_ mode_t u; + + assert(dest); + + u = umask(0000); + + /* Create /dev/net, so that we can create /dev/net/tun in it */ + if (userns_mkdir(dest, "/dev/net", 0755, 0, 0) < 0) + return log_error_errno(r, "Failed to create /dev/net directory: %m"); + + NULSTR_FOREACH(d, devnodes) { + _cleanup_free_ char *from = NULL, *to = NULL; + struct stat st; + + from = strappend("/dev/", d); + to = prefix_root(dest, from); + + if (stat(from, &st) < 0) { + + if (errno != ENOENT) + return log_error_errno(errno, "Failed to stat %s: %m", from); + + } else if (!S_ISCHR(st.st_mode) && !S_ISBLK(st.st_mode)) { + + log_error("%s is not a char or block device, cannot copy.", from); + return -EIO; + + } else { + if (mknod(to, st.st_mode, st.st_rdev) < 0) { + if (errno != EPERM) + return log_error_errno(errno, "mknod(%s) failed: %m", to); + + /* Some systems abusively restrict mknod but + * allow bind mounts. */ + r = touch(to); + if (r < 0) + return log_error_errno(r, "touch (%s) failed: %m", to); + if (mount(from, to, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Both mknod and bind mount (%s) failed: %m", to); + } + + r = userns_lchown(to, 0, 0); + if (r < 0) + return log_error_errno(r, "chown() of device node %s failed: %m", to); + } + } + + return r; +} + +static int setup_pts(const char *dest) { + _cleanup_free_ char *options = NULL; + const char *p; + int r; + +#ifdef HAVE_SELINUX + if (arg_selinux_apifs_context) + (void) asprintf(&options, + "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT ",context=\"%s\"", + arg_uid_shift + TTY_GID, + arg_selinux_apifs_context); + else +#endif + (void) asprintf(&options, + "newinstance,ptmxmode=0666,mode=620,gid=" GID_FMT, + arg_uid_shift + TTY_GID); + + if (!options) + return log_oom(); + + /* Mount /dev/pts itself */ + p = prefix_roota(dest, "/dev/pts"); + if (mkdir(p, 0755) < 0) + return log_error_errno(errno, "Failed to create /dev/pts: %m"); + if (mount("devpts", p, "devpts", MS_NOSUID|MS_NOEXEC, options) < 0) + return log_error_errno(errno, "Failed to mount /dev/pts: %m"); + r = userns_lchown(p, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to chown /dev/pts: %m"); + + /* Create /dev/ptmx symlink */ + p = prefix_roota(dest, "/dev/ptmx"); + if (symlink("pts/ptmx", p) < 0) + return log_error_errno(errno, "Failed to create /dev/ptmx symlink: %m"); + r = userns_lchown(p, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to chown /dev/ptmx: %m"); + + /* And fix /dev/pts/ptmx ownership */ + p = prefix_roota(dest, "/dev/pts/ptmx"); + r = userns_lchown(p, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to chown /dev/pts/ptmx: %m"); + + return 0; +} + +static int setup_dev_console(const char *dest, const char *console) { + _cleanup_umask_ mode_t u; + const char *to; + int r; + + assert(dest); + assert(console); + + u = umask(0000); + + r = chmod_and_chown(console, 0600, arg_uid_shift, arg_uid_shift); + if (r < 0) + return log_error_errno(r, "Failed to correct access mode for TTY: %m"); + + /* We need to bind mount the right tty to /dev/console since + * ptys can only exist on pts file systems. To have something + * to bind mount things on we create a empty regular file. */ + + to = prefix_roota(dest, "/dev/console"); + r = touch(to); + if (r < 0) + return log_error_errno(r, "touch() for /dev/console failed: %m"); + + if (mount(console, to, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Bind mount for /dev/console failed: %m"); + + return 0; +} + +static int setup_kmsg(const char *dest, int kmsg_socket) { + const char *from, *to; + _cleanup_umask_ mode_t u; + int fd, r; + + assert(kmsg_socket >= 0); + + u = umask(0000); + + /* We create the kmsg FIFO as /run/kmsg, but immediately + * delete it after bind mounting it to /proc/kmsg. While FIFOs + * on the reading side behave very similar to /proc/kmsg, + * their writing side behaves differently from /dev/kmsg in + * that writing blocks when nothing is reading. In order to + * avoid any problems with containers deadlocking due to this + * we simply make /dev/kmsg unavailable to the container. */ + from = prefix_roota(dest, "/run/kmsg"); + to = prefix_roota(dest, "/proc/kmsg"); + + if (mkfifo(from, 0600) < 0) + return log_error_errno(errno, "mkfifo() for /run/kmsg failed: %m"); + if (mount(from, to, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Bind mount for /proc/kmsg failed: %m"); + + fd = open(from, O_RDWR|O_NDELAY|O_CLOEXEC); + if (fd < 0) + return log_error_errno(errno, "Failed to open fifo: %m"); + + /* Store away the fd in the socket, so that it stays open as + * long as we run the child */ + r = send_one_fd(kmsg_socket, fd, 0); + safe_close(fd); + + if (r < 0) + return log_error_errno(r, "Failed to send FIFO fd: %m"); + + /* And now make the FIFO unavailable as /run/kmsg... */ + (void) unlink(from); + + return 0; +} + +static int on_address_change(sd_netlink *rtnl, sd_netlink_message *m, void *userdata) { + union in_addr_union *exposed = userdata; + + assert(rtnl); + assert(m); + assert(exposed); + + expose_port_execute(rtnl, arg_expose_ports, exposed); + return 0; +} + +static int setup_hostname(void) { + + if (arg_share_system) + return 0; + + if (sethostname_idempotent(arg_machine) < 0) + return -errno; + + return 0; +} + +static int setup_journal(const char *directory) { + sd_id128_t this_id; + _cleanup_free_ char *d = NULL; + const char *p, *q; + bool try; + char id[33]; + int r; + + /* Don't link journals in ephemeral mode */ + if (arg_ephemeral) + return 0; + + if (arg_link_journal == LINK_NO) + return 0; + + try = arg_link_journal_try || arg_link_journal == LINK_AUTO; + + r = sd_id128_get_machine(&this_id); + if (r < 0) + return log_error_errno(r, "Failed to retrieve machine ID: %m"); + + if (sd_id128_equal(arg_uuid, this_id)) { + log_full(try ? LOG_WARNING : LOG_ERR, + "Host and machine ids are equal (%s): refusing to link journals", sd_id128_to_string(arg_uuid, id)); + if (try) + return 0; + return -EEXIST; + } + + r = userns_mkdir(directory, "/var", 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /var: %m"); + + r = userns_mkdir(directory, "/var/log", 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /var/log: %m"); + + r = userns_mkdir(directory, "/var/log/journal", 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /var/log/journal: %m"); + + (void) sd_id128_to_string(arg_uuid, id); + + p = strjoina("/var/log/journal/", id); + q = prefix_roota(directory, p); + + if (path_is_mount_point(p, 0) > 0) { + if (try) + return 0; + + log_error("%s: already a mount point, refusing to use for journal", p); + return -EEXIST; + } + + if (path_is_mount_point(q, 0) > 0) { + if (try) + return 0; + + log_error("%s: already a mount point, refusing to use for journal", q); + return -EEXIST; + } + + r = readlink_and_make_absolute(p, &d); + if (r >= 0) { + if ((arg_link_journal == LINK_GUEST || + arg_link_journal == LINK_AUTO) && + path_equal(d, q)) { + + r = userns_mkdir(directory, p, 0755, 0, 0); + if (r < 0) + log_warning_errno(r, "Failed to create directory %s: %m", q); + return 0; + } + + if (unlink(p) < 0) + return log_error_errno(errno, "Failed to remove symlink %s: %m", p); + } else if (r == -EINVAL) { + + if (arg_link_journal == LINK_GUEST && + rmdir(p) < 0) { + + if (errno == ENOTDIR) { + log_error("%s already exists and is neither a symlink nor a directory", p); + return r; + } else + return log_error_errno(errno, "Failed to remove %s: %m", p); + } + } else if (r != -ENOENT) + return log_error_errno(r, "readlink(%s) failed: %m", p); + + if (arg_link_journal == LINK_GUEST) { + + if (symlink(q, p) < 0) { + if (try) { + log_debug_errno(errno, "Failed to symlink %s to %s, skipping journal setup: %m", q, p); + return 0; + } else + return log_error_errno(errno, "Failed to symlink %s to %s: %m", q, p); + } + + r = userns_mkdir(directory, p, 0755, 0, 0); + if (r < 0) + log_warning_errno(r, "Failed to create directory %s: %m", q); + return 0; + } + + if (arg_link_journal == LINK_HOST) { + /* don't create parents here — if the host doesn't have + * permanent journal set up, don't force it here */ + + if (mkdir(p, 0755) < 0 && errno != EEXIST) { + if (try) { + log_debug_errno(errno, "Failed to create %s, skipping journal setup: %m", p); + return 0; + } else + return log_error_errno(errno, "Failed to create %s: %m", p); + } + + } else if (access(p, F_OK) < 0) + return 0; + + if (dir_is_empty(q) == 0) + log_warning("%s is not empty, proceeding anyway.", q); + + r = userns_mkdir(directory, p, 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create %s: %m", q); + + if (mount(p, q, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Failed to bind mount journal from host into guest: %m"); + + return 0; +} + +static int drop_capabilities(void) { + return capability_bounding_set_drop(arg_retain, false); +} + +static int reset_audit_loginuid(void) { + _cleanup_free_ char *p = NULL; + int r; + + if (arg_share_system) + return 0; + + r = read_one_line_file("/proc/self/loginuid", &p); + if (r == -ENOENT) + return 0; + if (r < 0) + return log_error_errno(r, "Failed to read /proc/self/loginuid: %m"); + + /* Already reset? */ + if (streq(p, "4294967295")) + return 0; + + r = write_string_file("/proc/self/loginuid", "4294967295", 0); + if (r < 0) { + log_error_errno(r, + "Failed to reset audit login UID. This probably means that your kernel is too\n" + "old and you have audit enabled. Note that the auditing subsystem is known to\n" + "be incompatible with containers on old kernels. Please make sure to upgrade\n" + "your kernel or to off auditing with 'audit=0' on the kernel command line before\n" + "using systemd-nspawn. Sleeping for 5s... (%m)"); + + sleep(5); + } + + return 0; +} + +static int setup_seccomp(void) { + +#ifdef HAVE_SECCOMP + static const struct { + uint64_t capability; + int syscall_num; + } blacklist[] = { + { CAP_SYS_RAWIO, SCMP_SYS(iopl) }, + { CAP_SYS_RAWIO, SCMP_SYS(ioperm) }, + { CAP_SYS_BOOT, SCMP_SYS(kexec_load) }, + { CAP_SYS_ADMIN, SCMP_SYS(swapon) }, + { CAP_SYS_ADMIN, SCMP_SYS(swapoff) }, + { CAP_SYS_ADMIN, SCMP_SYS(open_by_handle_at) }, + { CAP_SYS_MODULE, SCMP_SYS(init_module) }, + { CAP_SYS_MODULE, SCMP_SYS(finit_module) }, + { CAP_SYS_MODULE, SCMP_SYS(delete_module) }, + { CAP_SYSLOG, SCMP_SYS(syslog) }, + }; + + scmp_filter_ctx seccomp; + unsigned i; + int r; + + seccomp = seccomp_init(SCMP_ACT_ALLOW); + if (!seccomp) + return log_oom(); + + r = seccomp_add_secondary_archs(seccomp); + if (r < 0) { + log_error_errno(r, "Failed to add secondary archs to seccomp filter: %m"); + goto finish; + } + + for (i = 0; i < ELEMENTSOF(blacklist); i++) { + if (arg_retain & (1ULL << blacklist[i].capability)) + continue; + + r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i].syscall_num, 0); + if (r == -EFAULT) + continue; /* unknown syscall */ + if (r < 0) { + log_error_errno(r, "Failed to block syscall: %m"); + goto finish; + } + } + + /* + Audit is broken in containers, much of the userspace audit + hookup will fail if running inside a container. We don't + care and just turn off creation of audit sockets. + + This will make socket(AF_NETLINK, *, NETLINK_AUDIT) fail + with EAFNOSUPPORT which audit userspace uses as indication + that audit is disabled in the kernel. + */ + + r = seccomp_rule_add( + seccomp, + SCMP_ACT_ERRNO(EAFNOSUPPORT), + SCMP_SYS(socket), + 2, + SCMP_A0(SCMP_CMP_EQ, AF_NETLINK), + SCMP_A2(SCMP_CMP_EQ, NETLINK_AUDIT)); + if (r < 0) { + log_error_errno(r, "Failed to add audit seccomp rule: %m"); + goto finish; + } + + r = seccomp_attr_set(seccomp, SCMP_FLTATR_CTL_NNP, 0); + if (r < 0) { + log_error_errno(r, "Failed to unset NO_NEW_PRIVS: %m"); + goto finish; + } + + r = seccomp_load(seccomp); + if (r == -EINVAL) { + log_debug_errno(r, "Kernel is probably not configured with CONFIG_SECCOMP. Disabling seccomp audit filter: %m"); + r = 0; + goto finish; + } + if (r < 0) { + log_error_errno(r, "Failed to install seccomp audit filter: %m"); + goto finish; + } + +finish: + seccomp_release(seccomp); + return r; +#else + return 0; +#endif + +} + +static int setup_propagate(const char *root) { + const char *p, *q; + int r; + + (void) mkdir_p("/run/systemd/nspawn/", 0755); + (void) mkdir_p("/run/systemd/nspawn/propagate", 0600); + p = strjoina("/run/systemd/nspawn/propagate/", arg_machine); + (void) mkdir_p(p, 0600); + + r = userns_mkdir(root, "/run/systemd", 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /run/systemd: %m"); + + r = userns_mkdir(root, "/run/systemd/nspawn", 0755, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /run/systemd/nspawn: %m"); + + r = userns_mkdir(root, "/run/systemd/nspawn/incoming", 0600, 0, 0); + if (r < 0) + return log_error_errno(r, "Failed to create /run/systemd/nspawn/incoming: %m"); + + q = prefix_roota(root, "/run/systemd/nspawn/incoming"); + if (mount(p, q, NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Failed to install propagation bind mount."); + + if (mount(NULL, q, NULL, MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) + return log_error_errno(errno, "Failed to make propagation mount read-only"); + + return 0; +} + +static int setup_image(char **device_path, int *loop_nr) { + struct loop_info64 info = { + .lo_flags = LO_FLAGS_AUTOCLEAR|LO_FLAGS_PARTSCAN + }; + _cleanup_close_ int fd = -1, control = -1, loop = -1; + _cleanup_free_ char* loopdev = NULL; + struct stat st; + int r, nr; + + assert(device_path); + assert(loop_nr); + assert(arg_image); + + fd = open(arg_image, O_CLOEXEC|(arg_read_only ? O_RDONLY : O_RDWR)|O_NONBLOCK|O_NOCTTY); + if (fd < 0) + return log_error_errno(errno, "Failed to open %s: %m", arg_image); + + if (fstat(fd, &st) < 0) + return log_error_errno(errno, "Failed to stat %s: %m", arg_image); + + if (S_ISBLK(st.st_mode)) { + char *p; + + p = strdup(arg_image); + if (!p) + return log_oom(); + + *device_path = p; + + *loop_nr = -1; + + r = fd; + fd = -1; + + return r; + } + + if (!S_ISREG(st.st_mode)) { + log_error("%s is not a regular file or block device.", arg_image); + return -EINVAL; + } + + control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK); + if (control < 0) + return log_error_errno(errno, "Failed to open /dev/loop-control: %m"); + + nr = ioctl(control, LOOP_CTL_GET_FREE); + if (nr < 0) + return log_error_errno(errno, "Failed to allocate loop device: %m"); + + if (asprintf(&loopdev, "/dev/loop%i", nr) < 0) + return log_oom(); + + loop = open(loopdev, O_CLOEXEC|(arg_read_only ? O_RDONLY : O_RDWR)|O_NONBLOCK|O_NOCTTY); + if (loop < 0) + return log_error_errno(errno, "Failed to open loop device %s: %m", loopdev); + + if (ioctl(loop, LOOP_SET_FD, fd) < 0) + return log_error_errno(errno, "Failed to set loopback file descriptor on %s: %m", loopdev); + + if (arg_read_only) + info.lo_flags |= LO_FLAGS_READ_ONLY; + + if (ioctl(loop, LOOP_SET_STATUS64, &info) < 0) + return log_error_errno(errno, "Failed to set loopback settings on %s: %m", loopdev); + + *device_path = loopdev; + loopdev = NULL; + + *loop_nr = nr; + + r = loop; + loop = -1; + + return r; +} + +#define PARTITION_TABLE_BLURB \ + "Note that the disk image needs to either contain only a single MBR partition of\n" \ + "type 0x83 that is marked bootable, or a single GPT partition of type " \ + "0FC63DAF-8483-4772-8E79-3D69D8477DE4 or follow\n" \ + " http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/\n" \ + "to be bootable with systemd-nspawn." + +static int dissect_image( + int fd, + char **root_device, bool *root_device_rw, + char **home_device, bool *home_device_rw, + char **srv_device, bool *srv_device_rw, + bool *secondary) { + +#ifdef HAVE_BLKID + int home_nr = -1, srv_nr = -1; +#ifdef GPT_ROOT_NATIVE + int root_nr = -1; +#endif +#ifdef GPT_ROOT_SECONDARY + int secondary_root_nr = -1; +#endif + _cleanup_free_ char *home = NULL, *root = NULL, *secondary_root = NULL, *srv = NULL, *generic = NULL; + _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL; + _cleanup_udev_device_unref_ struct udev_device *d = NULL; + _cleanup_blkid_free_probe_ blkid_probe b = NULL; + _cleanup_udev_unref_ struct udev *udev = NULL; + struct udev_list_entry *first, *item; + bool home_rw = true, root_rw = true, secondary_root_rw = true, srv_rw = true, generic_rw = true; + bool is_gpt, is_mbr, multiple_generic = false; + const char *pttype = NULL; + blkid_partlist pl; + struct stat st; + unsigned i; + int r; + + assert(fd >= 0); + assert(root_device); + assert(home_device); + assert(srv_device); + assert(secondary); + assert(arg_image); + + b = blkid_new_probe(); + if (!b) + return log_oom(); + + errno = 0; + r = blkid_probe_set_device(b, fd, 0, 0); + if (r != 0) { + if (errno == 0) + return log_oom(); + + return log_error_errno(errno, "Failed to set device on blkid probe: %m"); + } + + blkid_probe_enable_partitions(b, 1); + blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS); + + errno = 0; + r = blkid_do_safeprobe(b); + if (r == -2 || r == 1) { + log_error("Failed to identify any partition table on\n" + " %s\n" + PARTITION_TABLE_BLURB, arg_image); + return -EINVAL; + } else if (r != 0) { + if (errno == 0) + errno = EIO; + return log_error_errno(errno, "Failed to probe: %m"); + } + + (void) blkid_probe_lookup_value(b, "PTTYPE", &pttype, NULL); + + is_gpt = streq_ptr(pttype, "gpt"); + is_mbr = streq_ptr(pttype, "dos"); + + if (!is_gpt && !is_mbr) { + log_error("No GPT or MBR partition table discovered on\n" + " %s\n" + PARTITION_TABLE_BLURB, arg_image); + return -EINVAL; + } + + errno = 0; + pl = blkid_probe_get_partitions(b); + if (!pl) { + if (errno == 0) + return log_oom(); + + log_error("Failed to list partitions of %s", arg_image); + return -errno; + } + + udev = udev_new(); + if (!udev) + return log_oom(); + + if (fstat(fd, &st) < 0) + return log_error_errno(errno, "Failed to stat block device: %m"); + + d = udev_device_new_from_devnum(udev, 'b', st.st_rdev); + if (!d) + return log_oom(); + + for (i = 0;; i++) { + int n, m; + + if (i >= 10) { + log_error("Kernel partitions never appeared."); + return -ENXIO; + } + + e = udev_enumerate_new(udev); + if (!e) + return log_oom(); + + r = udev_enumerate_add_match_parent(e, d); + if (r < 0) + return log_oom(); + + r = udev_enumerate_scan_devices(e); + if (r < 0) + return log_error_errno(r, "Failed to scan for partition devices of %s: %m", arg_image); + + /* Count the partitions enumerated by the kernel */ + n = 0; + first = udev_enumerate_get_list_entry(e); + udev_list_entry_foreach(item, first) + n++; + + /* Count the partitions enumerated by blkid */ + m = blkid_partlist_numof_partitions(pl); + if (n == m + 1) + break; + if (n > m + 1) { + log_error("blkid and kernel partition list do not match."); + return -EIO; + } + if (n < m + 1) { + unsigned j; + + /* The kernel has probed fewer partitions than + * blkid? Maybe the kernel prober is still + * running or it got EBUSY because udev + * already opened the device. Let's reprobe + * the device, which is a synchronous call + * that waits until probing is complete. */ + + for (j = 0; j < 20; j++) { + + r = ioctl(fd, BLKRRPART, 0); + if (r < 0) + r = -errno; + if (r >= 0 || r != -EBUSY) + break; + + /* If something else has the device + * open, such as an udev rule, the + * ioctl will return EBUSY. Since + * there's no way to wait until it + * isn't busy anymore, let's just wait + * a bit, and try again. + * + * This is really something they + * should fix in the kernel! */ + + usleep(50 * USEC_PER_MSEC); + } + + if (r < 0) + return log_error_errno(r, "Failed to reread partition table: %m"); + } + + e = udev_enumerate_unref(e); + } + + first = udev_enumerate_get_list_entry(e); + udev_list_entry_foreach(item, first) { + _cleanup_udev_device_unref_ struct udev_device *q; + const char *node; + unsigned long long flags; + blkid_partition pp; + dev_t qn; + int nr; + + errno = 0; + q = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item)); + if (!q) { + if (!errno) + errno = ENOMEM; + + return log_error_errno(errno, "Failed to get partition device of %s: %m", arg_image); + } + + qn = udev_device_get_devnum(q); + if (major(qn) == 0) + continue; + + if (st.st_rdev == qn) + continue; + + node = udev_device_get_devnode(q); + if (!node) + continue; + + pp = blkid_partlist_devno_to_partition(pl, qn); + if (!pp) + continue; + + flags = blkid_partition_get_flags(pp); + + nr = blkid_partition_get_partno(pp); + if (nr < 0) + continue; + + if (is_gpt) { + sd_id128_t type_id; + const char *stype; + + if (flags & GPT_FLAG_NO_AUTO) + continue; + + stype = blkid_partition_get_type_string(pp); + if (!stype) + continue; + + if (sd_id128_from_string(stype, &type_id) < 0) + continue; + + if (sd_id128_equal(type_id, GPT_HOME)) { + + if (home && nr >= home_nr) + continue; + + home_nr = nr; + home_rw = !(flags & GPT_FLAG_READ_ONLY); + + r = free_and_strdup(&home, node); + if (r < 0) + return log_oom(); + + } else if (sd_id128_equal(type_id, GPT_SRV)) { + + if (srv && nr >= srv_nr) + continue; + + srv_nr = nr; + srv_rw = !(flags & GPT_FLAG_READ_ONLY); + + r = free_and_strdup(&srv, node); + if (r < 0) + return log_oom(); + } +#ifdef GPT_ROOT_NATIVE + else if (sd_id128_equal(type_id, GPT_ROOT_NATIVE)) { + + if (root && nr >= root_nr) + continue; + + root_nr = nr; + root_rw = !(flags & GPT_FLAG_READ_ONLY); + + r = free_and_strdup(&root, node); + if (r < 0) + return log_oom(); + } +#endif +#ifdef GPT_ROOT_SECONDARY + else if (sd_id128_equal(type_id, GPT_ROOT_SECONDARY)) { + + if (secondary_root && nr >= secondary_root_nr) + continue; + + secondary_root_nr = nr; + secondary_root_rw = !(flags & GPT_FLAG_READ_ONLY); + + r = free_and_strdup(&secondary_root, node); + if (r < 0) + return log_oom(); + } +#endif + else if (sd_id128_equal(type_id, GPT_LINUX_GENERIC)) { + + if (generic) + multiple_generic = true; + else { + generic_rw = !(flags & GPT_FLAG_READ_ONLY); + + r = free_and_strdup(&generic, node); + if (r < 0) + return log_oom(); + } + } + + } else if (is_mbr) { + int type; + + if (flags != 0x80) /* Bootable flag */ + continue; + + type = blkid_partition_get_type(pp); + if (type != 0x83) /* Linux partition */ + continue; + + if (generic) + multiple_generic = true; + else { + generic_rw = true; + + r = free_and_strdup(&root, node); + if (r < 0) + return log_oom(); + } + } + } + + if (root) { + *root_device = root; + root = NULL; + + *root_device_rw = root_rw; + *secondary = false; + } else if (secondary_root) { + *root_device = secondary_root; + secondary_root = NULL; + + *root_device_rw = secondary_root_rw; + *secondary = true; + } else if (generic) { + + /* There were no partitions with precise meanings + * around, but we found generic partitions. In this + * case, if there's only one, we can go ahead and boot + * it, otherwise we bail out, because we really cannot + * make any sense of it. */ + + if (multiple_generic) { + log_error("Identified multiple bootable Linux partitions on\n" + " %s\n" + PARTITION_TABLE_BLURB, arg_image); + return -EINVAL; + } + + *root_device = generic; + generic = NULL; + + *root_device_rw = generic_rw; + *secondary = false; + } else { + log_error("Failed to identify root partition in disk image\n" + " %s\n" + PARTITION_TABLE_BLURB, arg_image); + return -EINVAL; + } + + if (home) { + *home_device = home; + home = NULL; + + *home_device_rw = home_rw; + } + + if (srv) { + *srv_device = srv; + srv = NULL; + + *srv_device_rw = srv_rw; + } + + return 0; +#else + log_error("--image= is not supported, compiled without blkid support."); + return -EOPNOTSUPP; +#endif +} + +static int mount_device(const char *what, const char *where, const char *directory, bool rw) { +#ifdef HAVE_BLKID + _cleanup_blkid_free_probe_ blkid_probe b = NULL; + const char *fstype, *p; + int r; + + assert(what); + assert(where); + + if (arg_read_only) + rw = false; + + if (directory) + p = strjoina(where, directory); + else + p = where; + + errno = 0; + b = blkid_new_probe_from_filename(what); + if (!b) { + if (errno == 0) + return log_oom(); + return log_error_errno(errno, "Failed to allocate prober for %s: %m", what); + } + + blkid_probe_enable_superblocks(b, 1); + blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE); + + errno = 0; + r = blkid_do_safeprobe(b); + if (r == -1 || r == 1) { + log_error("Cannot determine file system type of %s", what); + return -EINVAL; + } else if (r != 0) { + if (errno == 0) + errno = EIO; + return log_error_errno(errno, "Failed to probe %s: %m", what); + } + + errno = 0; + if (blkid_probe_lookup_value(b, "TYPE", &fstype, NULL) < 0) { + if (errno == 0) + errno = EINVAL; + log_error("Failed to determine file system type of %s", what); + return -errno; + } + + if (streq(fstype, "crypto_LUKS")) { + log_error("nspawn currently does not support LUKS disk images."); + return -EOPNOTSUPP; + } + + if (mount(what, p, fstype, MS_NODEV|(rw ? 0 : MS_RDONLY), NULL) < 0) + return log_error_errno(errno, "Failed to mount %s: %m", what); + + return 0; +#else + log_error("--image= is not supported, compiled without blkid support."); + return -EOPNOTSUPP; +#endif +} + +static int setup_machine_id(const char *directory) { + int r; + const char *etc_machine_id, *t; + _cleanup_free_ char *s = NULL; + + etc_machine_id = prefix_roota(directory, "/etc/machine-id"); + + r = read_one_line_file(etc_machine_id, &s); + if (r < 0) + return log_error_errno(r, "Failed to read machine ID from %s: %m", etc_machine_id); + + t = strstrip(s); + + if (!isempty(t)) { + r = sd_id128_from_string(t, &arg_uuid); + if (r < 0) + return log_error_errno(r, "Failed to parse machine ID from %s: %m", etc_machine_id); + } else { + if (sd_id128_is_null(arg_uuid)) { + r = sd_id128_randomize(&arg_uuid); + if (r < 0) + return log_error_errno(r, "Failed to generate random machine ID: %m"); + } + } + + r = machine_id_setup(directory, arg_uuid); + if (r < 0) + return log_error_errno(r, "Failed to setup machine ID: %m"); + + return 0; +} + +static int recursive_chown(const char *directory, uid_t shift, uid_t range) { + int r; + + assert(directory); + + if (arg_userns_mode == USER_NAMESPACE_NO || !arg_userns_chown) + return 0; + + r = path_patch_uid(directory, arg_uid_shift, arg_uid_range); + if (r == -EOPNOTSUPP) + return log_error_errno(r, "Automatic UID/GID adjusting is only supported for UID/GID ranges starting at multiples of 2^16 with a range of 2^16."); + if (r == -EBADE) + return log_error_errno(r, "Upper 16 bits of root directory UID and GID do not match."); + if (r < 0) + return log_error_errno(r, "Failed to adjust UID/GID shift of OS tree: %m"); + if (r == 0) + log_debug("Root directory of image is already owned by the right UID/GID range, skipping recursive chown operation."); + else + log_debug("Patched directory tree to match UID/GID range."); + + return r; +} + +static int mount_devices( + const char *where, + const char *root_device, bool root_device_rw, + const char *home_device, bool home_device_rw, + const char *srv_device, bool srv_device_rw) { + int r; + + assert(where); + + if (root_device) { + r = mount_device(root_device, arg_directory, NULL, root_device_rw); + if (r < 0) + return log_error_errno(r, "Failed to mount root directory: %m"); + } + + if (home_device) { + r = mount_device(home_device, arg_directory, "/home", home_device_rw); + if (r < 0) + return log_error_errno(r, "Failed to mount home directory: %m"); + } + + if (srv_device) { + r = mount_device(srv_device, arg_directory, "/srv", srv_device_rw); + if (r < 0) + return log_error_errno(r, "Failed to mount server data directory: %m"); + } + + return 0; +} + +static void loop_remove(int nr, int *image_fd) { + _cleanup_close_ int control = -1; + int r; + + if (nr < 0) + return; + + if (image_fd && *image_fd >= 0) { + r = ioctl(*image_fd, LOOP_CLR_FD); + if (r < 0) + log_debug_errno(errno, "Failed to close loop image: %m"); + *image_fd = safe_close(*image_fd); + } + + control = open("/dev/loop-control", O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK); + if (control < 0) { + log_warning_errno(errno, "Failed to open /dev/loop-control: %m"); + return; + } + + r = ioctl(control, LOOP_CTL_REMOVE, nr); + if (r < 0) + log_debug_errno(errno, "Failed to remove loop %d: %m", nr); +} + +/* + * Return values: + * < 0 : wait_for_terminate() failed to get the state of the + * container, the container was terminated by a signal, or + * failed for an unknown reason. No change is made to the + * container argument. + * > 0 : The program executed in the container terminated with an + * error. The exit code of the program executed in the + * container is returned. The container argument has been set + * to CONTAINER_TERMINATED. + * 0 : The container is being rebooted, has been shut down or exited + * successfully. The container argument has been set to either + * CONTAINER_TERMINATED or CONTAINER_REBOOTED. + * + * That is, success is indicated by a return value of zero, and an + * error is indicated by a non-zero value. + */ +static int wait_for_container(pid_t pid, ContainerStatus *container) { + siginfo_t status; + int r; + + r = wait_for_terminate(pid, &status); + if (r < 0) + return log_warning_errno(r, "Failed to wait for container: %m"); + + switch (status.si_code) { + + case CLD_EXITED: + if (status.si_status == 0) { + log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s exited successfully.", arg_machine); + + } else + log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s failed with error code %i.", arg_machine, status.si_status); + + *container = CONTAINER_TERMINATED; + return status.si_status; + + case CLD_KILLED: + if (status.si_status == SIGINT) { + + log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s has been shut down.", arg_machine); + *container = CONTAINER_TERMINATED; + return 0; + + } else if (status.si_status == SIGHUP) { + + log_full(arg_quiet ? LOG_DEBUG : LOG_INFO, "Container %s is being rebooted.", arg_machine); + *container = CONTAINER_REBOOTED; + return 0; + } + + /* CLD_KILLED fallthrough */ + + case CLD_DUMPED: + log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status)); + return -EIO; + + default: + log_error("Container %s failed due to unknown reason.", arg_machine); + return -EIO; + } + + return r; +} + +static int on_orderly_shutdown(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) { + pid_t pid; + + pid = PTR_TO_PID(userdata); + if (pid > 0) { + if (kill(pid, arg_kill_signal) >= 0) { + log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination."); + sd_event_source_set_userdata(s, NULL); + return 0; + } + } + + sd_event_exit(sd_event_source_get_event(s), 0); + return 0; +} + +static int determine_names(void) { + int r; + + if (arg_template && !arg_directory && arg_machine) { + + /* If --template= was specified then we should not + * search for a machine, but instead create a new one + * in /var/lib/machine. */ + + arg_directory = strjoin("/var/lib/machines/", arg_machine, NULL); + if (!arg_directory) + return log_oom(); + } + + if (!arg_image && !arg_directory) { + if (arg_machine) { + _cleanup_(image_unrefp) Image *i = NULL; + + r = image_find(arg_machine, &i); + if (r < 0) + return log_error_errno(r, "Failed to find image for machine '%s': %m", arg_machine); + else if (r == 0) { + log_error("No image for machine '%s': %m", arg_machine); + return -ENOENT; + } + + if (i->type == IMAGE_RAW) + r = free_and_strdup(&arg_image, i->path); + else + r = free_and_strdup(&arg_directory, i->path); + if (r < 0) + return log_error_errno(r, "Invalid image directory: %m"); + + if (!arg_ephemeral) + arg_read_only = arg_read_only || i->read_only; + } else + arg_directory = get_current_dir_name(); + + if (!arg_directory && !arg_machine) { + log_error("Failed to determine path, please use -D or -i."); + return -EINVAL; + } + } + + if (!arg_machine) { + if (arg_directory && path_equal(arg_directory, "/")) + arg_machine = gethostname_malloc(); + else + arg_machine = strdup(basename(arg_image ?: arg_directory)); + + if (!arg_machine) + return log_oom(); + + hostname_cleanup(arg_machine); + if (!machine_name_is_valid(arg_machine)) { + log_error("Failed to determine machine name automatically, please use -M."); + return -EINVAL; + } + + if (arg_ephemeral) { + char *b; + + /* Add a random suffix when this is an + * ephemeral machine, so that we can run many + * instances at once without manually having + * to specify -M each time. */ + + if (asprintf(&b, "%s-%016" PRIx64, arg_machine, random_u64()) < 0) + return log_oom(); + + free(arg_machine); + arg_machine = b; + } + } + + return 0; +} + +static int determine_uid_shift(const char *directory) { + int r; + + if (arg_userns_mode == USER_NAMESPACE_NO) { + arg_uid_shift = 0; + return 0; + } + + if (arg_uid_shift == UID_INVALID) { + struct stat st; + + r = stat(directory, &st); + if (r < 0) + return log_error_errno(errno, "Failed to determine UID base of %s: %m", directory); + + arg_uid_shift = st.st_uid & UINT32_C(0xffff0000); + + if (arg_uid_shift != (st.st_gid & UINT32_C(0xffff0000))) { + log_error("UID and GID base of %s don't match.", directory); + return -EINVAL; + } + + arg_uid_range = UINT32_C(0x10000); + } + + if (arg_uid_shift > (uid_t) -1 - arg_uid_range) { + log_error("UID base too high for UID range."); + return -EINVAL; + } + + return 0; +} + +static int inner_child( + Barrier *barrier, + const char *directory, + bool secondary, + int kmsg_socket, + int rtnl_socket, + FDSet *fds) { + + _cleanup_free_ char *home = NULL; + char as_uuid[37]; + unsigned n_env = 1; + const char *envp[] = { + "PATH=" DEFAULT_PATH_SPLIT_USR, + NULL, /* container */ + NULL, /* TERM */ + NULL, /* HOME */ + NULL, /* USER */ + NULL, /* LOGNAME */ + NULL, /* container_uuid */ + NULL, /* LISTEN_FDS */ + NULL, /* LISTEN_PID */ + NULL + }; + + _cleanup_strv_free_ char **env_use = NULL; + int r; + + assert(barrier); + assert(directory); + assert(kmsg_socket >= 0); + + cg_unified_flush(); + + if (arg_userns_mode != USER_NAMESPACE_NO) { + /* Tell the parent, that it now can write the UID map. */ + (void) barrier_place(barrier); /* #1 */ + + /* Wait until the parent wrote the UID map */ + if (!barrier_place_and_sync(barrier)) { /* #2 */ + log_error("Parent died too early"); + return -ESRCH; + } + } + + r = mount_all(NULL, + arg_userns_mode != USER_NAMESPACE_NO, + true, + arg_private_network, + arg_uid_shift, + arg_uid_range, + arg_selinux_apifs_context); + + if (r < 0) + return r; + + r = mount_sysfs(NULL); + if (r < 0) + return r; + + /* Wait until we are cgroup-ified, so that we + * can mount the right cgroup path writable */ + if (!barrier_place_and_sync(barrier)) { /* #3 */ + log_error("Parent died too early"); + return -ESRCH; + } + + r = mount_systemd_cgroup_writable("", arg_unified_cgroup_hierarchy); + if (r < 0) + return r; + + r = reset_uid_gid(); + if (r < 0) + return log_error_errno(r, "Couldn't become new root: %m"); + + r = setup_boot_id(NULL); + if (r < 0) + return r; + + r = setup_kmsg(NULL, kmsg_socket); + if (r < 0) + return r; + kmsg_socket = safe_close(kmsg_socket); + + umask(0022); + + if (setsid() < 0) + return log_error_errno(errno, "setsid() failed: %m"); + + if (arg_private_network) + loopback_setup(); + + if (arg_expose_ports) { + r = expose_port_send_rtnl(rtnl_socket); + if (r < 0) + return r; + rtnl_socket = safe_close(rtnl_socket); + } + + r = drop_capabilities(); + if (r < 0) + return log_error_errno(r, "drop_capabilities() failed: %m"); + + setup_hostname(); + + if (arg_personality != PERSONALITY_INVALID) { + if (personality(arg_personality) < 0) + return log_error_errno(errno, "personality() failed: %m"); + } else if (secondary) { + if (personality(PER_LINUX32) < 0) + return log_error_errno(errno, "personality() failed: %m"); + } + +#ifdef HAVE_SELINUX + if (arg_selinux_context) + if (setexeccon((security_context_t) arg_selinux_context) < 0) + return log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context); +#endif + + r = change_uid_gid(arg_user, &home); + if (r < 0) + return r; + + /* LXC sets container=lxc, so follow the scheme here */ + envp[n_env++] = strjoina("container=", arg_container_service_name); + + envp[n_env] = strv_find_prefix(environ, "TERM="); + if (envp[n_env]) + n_env++; + + if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) || + (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) || + (asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) + return log_oom(); + + assert(!sd_id128_equal(arg_uuid, SD_ID128_NULL)); + + if (asprintf((char**)(envp + n_env++), "container_uuid=%s", id128_format_as_uuid(arg_uuid, as_uuid)) < 0) + return log_oom(); + + if (fdset_size(fds) > 0) { + r = fdset_cloexec(fds, false); + if (r < 0) + return log_error_errno(r, "Failed to unset O_CLOEXEC for file descriptors."); + + if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", fdset_size(fds)) < 0) || + (asprintf((char **)(envp + n_env++), "LISTEN_PID=1") < 0)) + return log_oom(); + } + + env_use = strv_env_merge(2, envp, arg_setenv); + if (!env_use) + return log_oom(); + + /* Let the parent know that we are ready and + * wait until the parent is ready with the + * setup, too... */ + if (!barrier_place_and_sync(barrier)) { /* #4 */ + log_error("Parent died too early"); + return -ESRCH; + } + + if (arg_chdir) + if (chdir(arg_chdir) < 0) + return log_error_errno(errno, "Failed to change to specified working directory %s: %m", arg_chdir); + + if (arg_start_mode == START_PID2) { + r = stub_pid1(); + if (r < 0) + return r; + } + + /* Now, explicitly close the log, so that we + * then can close all remaining fds. Closing + * the log explicitly first has the benefit + * that the logging subsystem knows about it, + * and is thus ready to be reopened should we + * need it again. Note that the other fds + * closed here are at least the locking and + * barrier fds. */ + log_close(); + (void) fdset_close_others(fds); + + if (arg_start_mode == START_BOOT) { + char **a; + size_t m; + + /* Automatically search for the init system */ + + m = strv_length(arg_parameters); + a = newa(char*, m + 2); + memcpy_safe(a + 1, arg_parameters, m * sizeof(char*)); + a[1 + m] = NULL; + + a[0] = (char*) "/usr/lib/systemd/systemd"; + execve(a[0], a, env_use); + + a[0] = (char*) "/lib/systemd/systemd"; + execve(a[0], a, env_use); + + a[0] = (char*) "/sbin/init"; + execve(a[0], a, env_use); + } else if (!strv_isempty(arg_parameters)) + execvpe(arg_parameters[0], arg_parameters, env_use); + else { + if (!arg_chdir) + /* If we cannot change the directory, we'll end up in /, that is expected. */ + (void) chdir(home ?: "/root"); + + execle("/bin/bash", "-bash", NULL, env_use); + execle("/bin/sh", "-sh", NULL, env_use); + } + + r = -errno; + (void) log_open(); + return log_error_errno(r, "execv() failed: %m"); +} + +static int outer_child( + Barrier *barrier, + const char *directory, + const char *console, + const char *root_device, bool root_device_rw, + const char *home_device, bool home_device_rw, + const char *srv_device, bool srv_device_rw, + bool interactive, + bool secondary, + int pid_socket, + int uuid_socket, + int kmsg_socket, + int rtnl_socket, + int uid_shift_socket, + FDSet *fds) { + + pid_t pid; + ssize_t l; + int r; + + assert(barrier); + assert(directory); + assert(console); + assert(pid_socket >= 0); + assert(uuid_socket >= 0); + assert(kmsg_socket >= 0); + + cg_unified_flush(); + + if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) + return log_error_errno(errno, "PR_SET_PDEATHSIG failed: %m"); + + if (interactive) { + close_nointr(STDIN_FILENO); + close_nointr(STDOUT_FILENO); + close_nointr(STDERR_FILENO); + + r = open_terminal(console, O_RDWR); + if (r != STDIN_FILENO) { + if (r >= 0) { + safe_close(r); + r = -EINVAL; + } + + return log_error_errno(r, "Failed to open console: %m"); + } + + if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || + dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) + return log_error_errno(errno, "Failed to duplicate console: %m"); + } + + r = reset_audit_loginuid(); + if (r < 0) + return r; + + /* Mark everything as slave, so that we still + * receive mounts from the real root, but don't + * propagate mounts to the real root. */ + if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) + return log_error_errno(errno, "MS_SLAVE|MS_REC failed: %m"); + + r = mount_devices(directory, + root_device, root_device_rw, + home_device, home_device_rw, + srv_device, srv_device_rw); + if (r < 0) + return r; + + r = determine_uid_shift(directory); + if (r < 0) + return r; + + if (arg_userns_mode != USER_NAMESPACE_NO) { + /* Let the parent know which UID shift we read from the image */ + l = send(uid_shift_socket, &arg_uid_shift, sizeof(arg_uid_shift), MSG_NOSIGNAL); + if (l < 0) + return log_error_errno(errno, "Failed to send UID shift: %m"); + if (l != sizeof(arg_uid_shift)) { + log_error("Short write while sending UID shift."); + return -EIO; + } + + if (arg_userns_mode == USER_NAMESPACE_PICK) { + /* When we are supposed to pick the UID shift, the parent will check now whether the UID shift + * we just read from the image is available. If yes, it will send the UID shift back to us, if + * not it will pick a different one, and send it back to us. */ + + l = recv(uid_shift_socket, &arg_uid_shift, sizeof(arg_uid_shift), 0); + if (l < 0) + return log_error_errno(errno, "Failed to recv UID shift: %m"); + if (l != sizeof(arg_uid_shift)) { + log_error("Short read while recieving UID shift."); + return -EIO; + } + } + + log_info("Selected user namespace base " UID_FMT " and range " UID_FMT ".", arg_uid_shift, arg_uid_range); + } + + /* Turn directory into bind mount */ + if (mount(directory, directory, NULL, MS_BIND|MS_REC, NULL) < 0) + return log_error_errno(errno, "Failed to make bind mount: %m"); + + r = recursive_chown(directory, arg_uid_shift, arg_uid_range); + if (r < 0) + return r; + + r = setup_volatile( + directory, + arg_volatile_mode, + arg_userns_mode != USER_NAMESPACE_NO, + arg_uid_shift, + arg_uid_range, + arg_selinux_context); + if (r < 0) + return r; + + r = setup_volatile_state( + directory, + arg_volatile_mode, + arg_userns_mode != USER_NAMESPACE_NO, + arg_uid_shift, + arg_uid_range, + arg_selinux_context); + if (r < 0) + return r; + + r = base_filesystem_create(directory, arg_uid_shift, (gid_t) arg_uid_shift); + if (r < 0) + return r; + + if (arg_read_only) { + r = bind_remount_recursive(directory, true); + if (r < 0) + return log_error_errno(r, "Failed to make tree read-only: %m"); + } + + r = mount_all(directory, + arg_userns_mode != USER_NAMESPACE_NO, + false, + arg_private_network, + arg_uid_shift, + arg_uid_range, + arg_selinux_apifs_context); + if (r < 0) + return r; + + r = copy_devnodes(directory); + if (r < 0) + return r; + + dev_setup(directory, arg_uid_shift, arg_uid_shift); + + r = setup_pts(directory); + if (r < 0) + return r; + + r = setup_propagate(directory); + if (r < 0) + return r; + + r = setup_dev_console(directory, console); + if (r < 0) + return r; + + r = setup_seccomp(); + if (r < 0) + return r; + + r = setup_timezone(directory); + if (r < 0) + return r; + + r = setup_resolv_conf(directory); + if (r < 0) + return r; + + r = setup_machine_id(directory); + if (r < 0) + return r; + + r = setup_journal(directory); + if (r < 0) + return r; + + r = mount_custom( + directory, + arg_custom_mounts, + arg_n_custom_mounts, + arg_userns_mode != USER_NAMESPACE_NO, + arg_uid_shift, + arg_uid_range, + arg_selinux_apifs_context); + if (r < 0) + return r; + + r = mount_cgroups( + directory, + arg_unified_cgroup_hierarchy, + arg_userns_mode != USER_NAMESPACE_NO, + arg_uid_shift, + arg_uid_range, + arg_selinux_apifs_context); + if (r < 0) + return r; + + r = mount_move_root(directory); + if (r < 0) + return log_error_errno(r, "Failed to move root directory: %m"); + + pid = raw_clone(SIGCHLD|CLONE_NEWNS| + (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS) | + (arg_private_network ? CLONE_NEWNET : 0) | + (arg_userns_mode != USER_NAMESPACE_NO ? CLONE_NEWUSER : 0), + NULL); + if (pid < 0) + return log_error_errno(errno, "Failed to fork inner child: %m"); + if (pid == 0) { + pid_socket = safe_close(pid_socket); + uuid_socket = safe_close(uuid_socket); + uid_shift_socket = safe_close(uid_shift_socket); + + /* The inner child has all namespaces that are + * requested, so that we all are owned by the user if + * user namespaces are turned on. */ + + r = inner_child(barrier, directory, secondary, kmsg_socket, rtnl_socket, fds); + if (r < 0) + _exit(EXIT_FAILURE); + + _exit(EXIT_SUCCESS); + } + + l = send(pid_socket, &pid, sizeof(pid), MSG_NOSIGNAL); + if (l < 0) + return log_error_errno(errno, "Failed to send PID: %m"); + if (l != sizeof(pid)) { + log_error("Short write while sending PID."); + return -EIO; + } + + l = send(uuid_socket, &arg_uuid, sizeof(arg_uuid), MSG_NOSIGNAL); + if (l < 0) + return log_error_errno(errno, "Failed to send machine ID: %m"); + if (l != sizeof(arg_uuid)) { + log_error("Short write while sending machine ID."); + return -EIO; + } + + pid_socket = safe_close(pid_socket); + uuid_socket = safe_close(uuid_socket); + kmsg_socket = safe_close(kmsg_socket); + rtnl_socket = safe_close(rtnl_socket); + + return 0; +} + +static int uid_shift_pick(uid_t *shift, LockFile *ret_lock_file) { + unsigned n_tries = 100; + uid_t candidate; + int r; + + assert(shift); + assert(ret_lock_file); + assert(arg_userns_mode == USER_NAMESPACE_PICK); + assert(arg_uid_range == 0x10000U); + + candidate = *shift; + + (void) mkdir("/run/systemd/nspawn-uid", 0755); + + for (;;) { + char lock_path[strlen("/run/systemd/nspawn-uid/") + DECIMAL_STR_MAX(uid_t) + 1]; + _cleanup_release_lock_file_ LockFile lf = LOCK_FILE_INIT; + + if (--n_tries <= 0) + return -EBUSY; + + if (candidate < UID_SHIFT_PICK_MIN || candidate > UID_SHIFT_PICK_MAX) + goto next; + if ((candidate & UINT32_C(0xFFFF)) != 0) + goto next; + + xsprintf(lock_path, "/run/systemd/nspawn-uid/" UID_FMT, candidate); + r = make_lock_file(lock_path, LOCK_EX|LOCK_NB, &lf); + if (r == -EBUSY) /* Range already taken by another nspawn instance */ + goto next; + if (r < 0) + return r; + + /* Make some superficial checks whether the range is currently known in the user database */ + if (getpwuid(candidate)) + goto next; + if (getpwuid(candidate + UINT32_C(0xFFFE))) + goto next; + if (getgrgid(candidate)) + goto next; + if (getgrgid(candidate + UINT32_C(0xFFFE))) + goto next; + + *ret_lock_file = lf; + lf = (struct LockFile) LOCK_FILE_INIT; + *shift = candidate; + return 0; + + next: + random_bytes(&candidate, sizeof(candidate)); + candidate = (candidate % (UID_SHIFT_PICK_MAX - UID_SHIFT_PICK_MIN)) + UID_SHIFT_PICK_MIN; + candidate &= (uid_t) UINT32_C(0xFFFF0000); + } +} + +static int setup_uid_map(pid_t pid) { + char uid_map[strlen("/proc//uid_map") + DECIMAL_STR_MAX(uid_t) + 1], line[DECIMAL_STR_MAX(uid_t)*3+3+1]; + int r; + + assert(pid > 1); + + xsprintf(uid_map, "/proc/" PID_FMT "/uid_map", pid); + xsprintf(line, UID_FMT " " UID_FMT " " UID_FMT "\n", 0, arg_uid_shift, arg_uid_range); + r = write_string_file(uid_map, line, 0); + if (r < 0) + return log_error_errno(r, "Failed to write UID map: %m"); + + /* We always assign the same UID and GID ranges */ + xsprintf(uid_map, "/proc/" PID_FMT "/gid_map", pid); + r = write_string_file(uid_map, line, 0); + if (r < 0) + return log_error_errno(r, "Failed to write GID map: %m"); + + return 0; +} + +static int load_settings(void) { + _cleanup_(settings_freep) Settings *settings = NULL; + _cleanup_fclose_ FILE *f = NULL; + _cleanup_free_ char *p = NULL; + const char *fn, *i; + int r; + + /* If all settings are masked, there's no point in looking for + * the settings file */ + if ((arg_settings_mask & _SETTINGS_MASK_ALL) == _SETTINGS_MASK_ALL) + return 0; + + fn = strjoina(arg_machine, ".nspawn"); + + /* We first look in the admin's directories in /etc and /run */ + FOREACH_STRING(i, "/etc/systemd/nspawn", "/run/systemd/nspawn") { + _cleanup_free_ char *j = NULL; + + j = strjoin(i, "/", fn, NULL); + if (!j) + return log_oom(); + + f = fopen(j, "re"); + if (f) { + p = j; + j = NULL; + + /* By default, we trust configuration from /etc and /run */ + if (arg_settings_trusted < 0) + arg_settings_trusted = true; + + break; + } + + if (errno != ENOENT) + return log_error_errno(errno, "Failed to open %s: %m", j); + } + + if (!f) { + /* After that, let's look for a file next to the + * actual image we shall boot. */ + + if (arg_image) { + p = file_in_same_dir(arg_image, fn); + if (!p) + return log_oom(); + } else if (arg_directory) { + p = file_in_same_dir(arg_directory, fn); + if (!p) + return log_oom(); + } + + if (p) { + f = fopen(p, "re"); + if (!f && errno != ENOENT) + return log_error_errno(errno, "Failed to open %s: %m", p); + + /* By default, we do not trust configuration from /var/lib/machines */ + if (arg_settings_trusted < 0) + arg_settings_trusted = false; + } + } + + if (!f) + return 0; + + log_debug("Settings are trusted: %s", yes_no(arg_settings_trusted)); + + r = settings_load(f, p, &settings); + if (r < 0) + return r; + + /* Copy over bits from the settings, unless they have been + * explicitly masked by command line switches. */ + + if ((arg_settings_mask & SETTING_START_MODE) == 0 && + settings->start_mode >= 0) { + arg_start_mode = settings->start_mode; + + strv_free(arg_parameters); + arg_parameters = settings->parameters; + settings->parameters = NULL; + } + + if ((arg_settings_mask & SETTING_WORKING_DIRECTORY) == 0 && + settings->working_directory) { + free(arg_chdir); + arg_chdir = settings->working_directory; + settings->working_directory = NULL; + } + + if ((arg_settings_mask & SETTING_ENVIRONMENT) == 0 && + settings->environment) { + strv_free(arg_setenv); + arg_setenv = settings->environment; + settings->environment = NULL; + } + + if ((arg_settings_mask & SETTING_USER) == 0 && + settings->user) { + free(arg_user); + arg_user = settings->user; + settings->user = NULL; + } + + if ((arg_settings_mask & SETTING_CAPABILITY) == 0) { + uint64_t plus; + + plus = settings->capability; + if (settings_private_network(settings)) + plus |= (1ULL << CAP_NET_ADMIN); + + if (!arg_settings_trusted && plus != 0) { + if (settings->capability != 0) + log_warning("Ignoring Capability= setting, file %s is not trusted.", p); + } else + arg_retain |= plus; + + arg_retain &= ~settings->drop_capability; + } + + if ((arg_settings_mask & SETTING_KILL_SIGNAL) == 0 && + settings->kill_signal > 0) + arg_kill_signal = settings->kill_signal; + + if ((arg_settings_mask & SETTING_PERSONALITY) == 0 && + settings->personality != PERSONALITY_INVALID) + arg_personality = settings->personality; + + if ((arg_settings_mask & SETTING_MACHINE_ID) == 0 && + !sd_id128_is_null(settings->machine_id)) { + + if (!arg_settings_trusted) + log_warning("Ignoring MachineID= setting, file %s is not trusted.", p); + else + arg_uuid = settings->machine_id; + } + + if ((arg_settings_mask & SETTING_READ_ONLY) == 0 && + settings->read_only >= 0) + arg_read_only = settings->read_only; + + if ((arg_settings_mask & SETTING_VOLATILE_MODE) == 0 && + settings->volatile_mode != _VOLATILE_MODE_INVALID) + arg_volatile_mode = settings->volatile_mode; + + if ((arg_settings_mask & SETTING_CUSTOM_MOUNTS) == 0 && + settings->n_custom_mounts > 0) { + + if (!arg_settings_trusted) + log_warning("Ignoring TemporaryFileSystem=, Bind= and BindReadOnly= settings, file %s is not trusted.", p); + else { + custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts); + arg_custom_mounts = settings->custom_mounts; + arg_n_custom_mounts = settings->n_custom_mounts; + + settings->custom_mounts = NULL; + settings->n_custom_mounts = 0; + } + } + + if ((arg_settings_mask & SETTING_NETWORK) == 0 && + (settings->private_network >= 0 || + settings->network_veth >= 0 || + settings->network_bridge || + settings->network_zone || + settings->network_interfaces || + settings->network_macvlan || + settings->network_ipvlan || + settings->network_veth_extra)) { + + if (!arg_settings_trusted) + log_warning("Ignoring network settings, file %s is not trusted.", p); + else { + arg_network_veth = settings_network_veth(settings); + arg_private_network = settings_private_network(settings); + + strv_free(arg_network_interfaces); + arg_network_interfaces = settings->network_interfaces; + settings->network_interfaces = NULL; + + strv_free(arg_network_macvlan); + arg_network_macvlan = settings->network_macvlan; + settings->network_macvlan = NULL; + + strv_free(arg_network_ipvlan); + arg_network_ipvlan = settings->network_ipvlan; + settings->network_ipvlan = NULL; + + strv_free(arg_network_veth_extra); + arg_network_veth_extra = settings->network_veth_extra; + settings->network_veth_extra = NULL; + + free(arg_network_bridge); + arg_network_bridge = settings->network_bridge; + settings->network_bridge = NULL; + + free(arg_network_zone); + arg_network_zone = settings->network_zone; + settings->network_zone = NULL; + } + } + + if ((arg_settings_mask & SETTING_EXPOSE_PORTS) == 0 && + settings->expose_ports) { + + if (!arg_settings_trusted) + log_warning("Ignoring Port= setting, file %s is not trusted.", p); + else { + expose_port_free_all(arg_expose_ports); + arg_expose_ports = settings->expose_ports; + settings->expose_ports = NULL; + } + } + + if ((arg_settings_mask & SETTING_USERNS) == 0 && + settings->userns_mode != _USER_NAMESPACE_MODE_INVALID) { + + if (!arg_settings_trusted) + log_warning("Ignoring PrivateUsers= and PrivateUsersChown= settings, file %s is not trusted.", p); + else { + arg_userns_mode = settings->userns_mode; + arg_uid_shift = settings->uid_shift; + arg_uid_range = settings->uid_range; + arg_userns_chown = settings->userns_chown; + } + } + + return 0; +} + +int main(int argc, char *argv[]) { + + _cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL, *console = NULL; + bool root_device_rw = true, home_device_rw = true, srv_device_rw = true; + _cleanup_close_ int master = -1, image_fd = -1; + _cleanup_fdset_free_ FDSet *fds = NULL; + int r, n_fd_passed, loop_nr = -1; + char veth_name[IFNAMSIZ] = ""; + bool secondary = false, remove_subvol = false; + sigset_t mask_chld; + pid_t pid = 0; + int ret = EXIT_SUCCESS; + union in_addr_union exposed = {}; + _cleanup_release_lock_file_ LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT; + bool interactive, veth_created = false; + + log_parse_environment(); + log_open(); + + /* Make sure rename_process() in the stub init process can work */ + saved_argv = argv; + saved_argc = argc; + + r = parse_argv(argc, argv); + if (r <= 0) + goto finish; + + if (geteuid() != 0) { + log_error("Need to be root."); + r = -EPERM; + goto finish; + } + r = determine_names(); + if (r < 0) + goto finish; + + r = load_settings(); + if (r < 0) + goto finish; + + r = verify_arguments(); + if (r < 0) + goto finish; + + n_fd_passed = sd_listen_fds(false); + if (n_fd_passed > 0) { + r = fdset_new_listen_fds(&fds, false); + if (r < 0) { + log_error_errno(r, "Failed to collect file descriptors: %m"); + goto finish; + } + } + + if (arg_directory) { + assert(!arg_image); + + if (path_equal(arg_directory, "/") && !arg_ephemeral) { + log_error("Spawning container on root directory is not supported. Consider using --ephemeral."); + r = -EINVAL; + goto finish; + } + + if (arg_ephemeral) { + _cleanup_free_ char *np = NULL; + + /* If the specified path is a mount point we + * generate the new snapshot immediately + * inside it under a random name. However if + * the specified is not a mount point we + * create the new snapshot in the parent + * directory, just next to it. */ + r = path_is_mount_point(arg_directory, 0); + if (r < 0) { + log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory); + goto finish; + } + if (r > 0) + r = tempfn_random_child(arg_directory, "machine.", &np); + else + r = tempfn_random(arg_directory, "machine.", &np); + if (r < 0) { + log_error_errno(r, "Failed to generate name for snapshot: %m"); + goto finish; + } + + r = image_path_lock(np, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock); + if (r < 0) { + log_error_errno(r, "Failed to lock %s: %m", np); + goto finish; + } + + r = btrfs_subvol_snapshot(arg_directory, np, (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) | BTRFS_SNAPSHOT_FALLBACK_COPY | BTRFS_SNAPSHOT_RECURSIVE | BTRFS_SNAPSHOT_QUOTA); + if (r < 0) { + log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory); + goto finish; + } + + free(arg_directory); + arg_directory = np; + np = NULL; + + remove_subvol = true; + + } else { + r = image_path_lock(arg_directory, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock); + if (r == -EBUSY) { + log_error_errno(r, "Directory tree %s is currently busy.", arg_directory); + goto finish; + } + if (r < 0) { + log_error_errno(r, "Failed to lock %s: %m", arg_directory); + return r; + } + + if (arg_template) { + r = btrfs_subvol_snapshot(arg_template, arg_directory, (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) | BTRFS_SNAPSHOT_FALLBACK_COPY | BTRFS_SNAPSHOT_RECURSIVE | BTRFS_SNAPSHOT_QUOTA); + if (r == -EEXIST) { + if (!arg_quiet) + log_info("Directory %s already exists, not populating from template %s.", arg_directory, arg_template); + } else if (r < 0) { + log_error_errno(r, "Couldn't create snapshot %s from %s: %m", arg_directory, arg_template); + goto finish; + } else { + if (!arg_quiet) + log_info("Populated %s from template %s.", arg_directory, arg_template); + } + } + } + + if (arg_start_mode == START_BOOT) { + if (path_is_os_tree(arg_directory) <= 0) { + log_error("Directory %s doesn't look like an OS root directory (os-release file is missing). Refusing.", arg_directory); + r = -EINVAL; + goto finish; + } + } else { + const char *p; + + p = strjoina(arg_directory, "/usr/"); + if (laccess(p, F_OK) < 0) { + log_error("Directory %s doesn't look like it has an OS tree. Refusing.", arg_directory); + r = -EINVAL; + goto finish; + } + } + + } else { + char template[] = "/tmp/nspawn-root-XXXXXX"; + + assert(arg_image); + assert(!arg_template); + + r = image_path_lock(arg_image, (arg_read_only ? LOCK_SH : LOCK_EX) | LOCK_NB, &tree_global_lock, &tree_local_lock); + if (r == -EBUSY) { + r = log_error_errno(r, "Disk image %s is currently busy.", arg_image); + goto finish; + } + if (r < 0) { + r = log_error_errno(r, "Failed to create image lock: %m"); + goto finish; + } + + if (!mkdtemp(template)) { + log_error_errno(errno, "Failed to create temporary directory: %m"); + r = -errno; + goto finish; + } + + arg_directory = strdup(template); + if (!arg_directory) { + r = log_oom(); + goto finish; + } + + image_fd = setup_image(&device_path, &loop_nr); + if (image_fd < 0) { + r = image_fd; + goto finish; + } + + r = dissect_image(image_fd, + &root_device, &root_device_rw, + &home_device, &home_device_rw, + &srv_device, &srv_device_rw, + &secondary); + if (r < 0) + goto finish; + } + + r = custom_mounts_prepare(); + if (r < 0) + goto finish; + + interactive = + isatty(STDIN_FILENO) > 0 && + isatty(STDOUT_FILENO) > 0; + + master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); + if (master < 0) { + r = log_error_errno(errno, "Failed to acquire pseudo tty: %m"); + goto finish; + } + + r = ptsname_malloc(master, &console); + if (r < 0) { + r = log_error_errno(r, "Failed to determine tty name: %m"); + goto finish; + } + + if (arg_selinux_apifs_context) { + r = mac_selinux_apply(console, arg_selinux_apifs_context); + if (r < 0) + goto finish; + } + + if (unlockpt(master) < 0) { + r = log_error_errno(errno, "Failed to unlock tty: %m"); + goto finish; + } + + if (!arg_quiet) + log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.", + arg_machine, arg_image ?: arg_directory); + + assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1) >= 0); + + assert_se(sigemptyset(&mask_chld) == 0); + assert_se(sigaddset(&mask_chld, SIGCHLD) == 0); + + if (prctl(PR_SET_CHILD_SUBREAPER, 1) < 0) { + r = log_error_errno(errno, "Failed to become subreaper: %m"); + goto finish; + } + + for (;;) { + static const struct sigaction sa = { + .sa_handler = nop_signal_handler, + .sa_flags = SA_NOCLDSTOP, + }; + + _cleanup_release_lock_file_ LockFile uid_shift_lock = LOCK_FILE_INIT; + _cleanup_close_ int etc_passwd_lock = -1; + _cleanup_close_pair_ int + kmsg_socket_pair[2] = { -1, -1 }, + rtnl_socket_pair[2] = { -1, -1 }, + pid_socket_pair[2] = { -1, -1 }, + uuid_socket_pair[2] = { -1, -1 }, + uid_shift_socket_pair[2] = { -1, -1 }; + _cleanup_(barrier_destroy) Barrier barrier = BARRIER_NULL; + _cleanup_(sd_event_unrefp) sd_event *event = NULL; + _cleanup_(pty_forward_freep) PTYForward *forward = NULL; + _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL; + ContainerStatus container_status; + char last_char = 0; + int ifi = 0; + ssize_t l; + + if (arg_userns_mode == USER_NAMESPACE_PICK) { + /* When we shall pick the UID/GID range, let's first lock /etc/passwd, so that we can safely + * check with getpwuid() if the specific user already exists. Note that /etc might be + * read-only, in which case this will fail with EROFS. But that's really OK, as in that case we + * can be reasonably sure that no users are going to be added. Note that getpwuid() checks are + * really just an extra safety net. We kinda assume that the UID range we allocate from is + * really ours. */ + + etc_passwd_lock = take_etc_passwd_lock(NULL); + if (etc_passwd_lock < 0 && etc_passwd_lock != -EROFS) { + log_error_errno(r, "Failed to take /etc/passwd lock: %m"); + goto finish; + } + } + + r = barrier_create(&barrier); + if (r < 0) { + log_error_errno(r, "Cannot initialize IPC barrier: %m"); + goto finish; + } + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) { + r = log_error_errno(errno, "Failed to create kmsg socket pair: %m"); + goto finish; + } + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, rtnl_socket_pair) < 0) { + r = log_error_errno(errno, "Failed to create rtnl socket pair: %m"); + goto finish; + } + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pid_socket_pair) < 0) { + r = log_error_errno(errno, "Failed to create pid socket pair: %m"); + goto finish; + } + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uuid_socket_pair) < 0) { + r = log_error_errno(errno, "Failed to create id socket pair: %m"); + goto finish; + } + + if (arg_userns_mode != USER_NAMESPACE_NO) + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, uid_shift_socket_pair) < 0) { + r = log_error_errno(errno, "Failed to create uid shift socket pair: %m"); + goto finish; + } + + /* Child can be killed before execv(), so handle SIGCHLD + * in order to interrupt parent's blocking calls and + * give it a chance to call wait() and terminate. */ + r = sigprocmask(SIG_UNBLOCK, &mask_chld, NULL); + if (r < 0) { + r = log_error_errno(errno, "Failed to change the signal mask: %m"); + goto finish; + } + + r = sigaction(SIGCHLD, &sa, NULL); + if (r < 0) { + r = log_error_errno(errno, "Failed to install SIGCHLD handler: %m"); + goto finish; + } + + pid = raw_clone(SIGCHLD|CLONE_NEWNS, NULL); + if (pid < 0) { + if (errno == EINVAL) + r = log_error_errno(errno, "clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m"); + else + r = log_error_errno(errno, "clone() failed: %m"); + + goto finish; + } + + if (pid == 0) { + /* The outer child only has a file system namespace. */ + barrier_set_role(&barrier, BARRIER_CHILD); + + master = safe_close(master); + + kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]); + rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]); + pid_socket_pair[0] = safe_close(pid_socket_pair[0]); + uuid_socket_pair[0] = safe_close(uuid_socket_pair[0]); + uid_shift_socket_pair[0] = safe_close(uid_shift_socket_pair[0]); + + (void) reset_all_signal_handlers(); + (void) reset_signal_mask(); + + r = outer_child(&barrier, + arg_directory, + console, + root_device, root_device_rw, + home_device, home_device_rw, + srv_device, srv_device_rw, + interactive, + secondary, + pid_socket_pair[1], + uuid_socket_pair[1], + kmsg_socket_pair[1], + rtnl_socket_pair[1], + uid_shift_socket_pair[1], + fds); + if (r < 0) + _exit(EXIT_FAILURE); + + _exit(EXIT_SUCCESS); + } + + barrier_set_role(&barrier, BARRIER_PARENT); + + fds = fdset_free(fds); + + kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]); + rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]); + pid_socket_pair[1] = safe_close(pid_socket_pair[1]); + uuid_socket_pair[1] = safe_close(uuid_socket_pair[1]); + uid_shift_socket_pair[1] = safe_close(uid_shift_socket_pair[1]); + + if (arg_userns_mode != USER_NAMESPACE_NO) { + /* The child just let us know the UID shift it might have read from the image. */ + l = recv(uid_shift_socket_pair[0], &arg_uid_shift, sizeof(arg_uid_shift), 0); + if (l < 0) { + r = log_error_errno(errno, "Failed to read UID shift: %m"); + goto finish; + } + if (l != sizeof(arg_uid_shift)) { + log_error("Short read while reading UID shift."); + r = EIO; + goto finish; + } + + if (arg_userns_mode == USER_NAMESPACE_PICK) { + /* If we are supposed to pick the UID shift, let's try to use the shift read from the + * image, but if that's already in use, pick a new one, and report back to the child, + * which one we now picked. */ + + r = uid_shift_pick(&arg_uid_shift, &uid_shift_lock); + if (r < 0) { + log_error_errno(r, "Failed to pick suitable UID/GID range: %m"); + goto finish; + } + + l = send(uid_shift_socket_pair[0], &arg_uid_shift, sizeof(arg_uid_shift), MSG_NOSIGNAL); + if (l < 0) { + r = log_error_errno(errno, "Failed to send UID shift: %m"); + goto finish; + } + if (l != sizeof(arg_uid_shift)) { + log_error("Short write while writing UID shift."); + r = -EIO; + goto finish; + } + } + } + + /* Wait for the outer child. */ + r = wait_for_terminate_and_warn("namespace helper", pid, NULL); + if (r < 0) + goto finish; + if (r != 0) { + r = -EIO; + goto finish; + } + pid = 0; + + /* And now retrieve the PID of the inner child. */ + l = recv(pid_socket_pair[0], &pid, sizeof(pid), 0); + if (l < 0) { + r = log_error_errno(errno, "Failed to read inner child PID: %m"); + goto finish; + } + if (l != sizeof(pid)) { + log_error("Short read while reading inner child PID."); + r = EIO; + goto finish; + } + + /* We also retrieve container UUID in case it was generated by outer child */ + l = recv(uuid_socket_pair[0], &arg_uuid, sizeof(arg_uuid), 0); + if (l < 0) { + r = log_error_errno(errno, "Failed to read container machine ID: %m"); + goto finish; + } + if (l != sizeof(arg_uuid)) { + log_error("Short read while reading container machined ID."); + r = EIO; + goto finish; + } + + log_debug("Init process invoked as PID " PID_FMT, pid); + + if (arg_userns_mode != USER_NAMESPACE_NO) { + if (!barrier_place_and_sync(&barrier)) { /* #1 */ + log_error("Child died too early."); + r = -ESRCH; + goto finish; + } + + r = setup_uid_map(pid); + if (r < 0) + goto finish; + + (void) barrier_place(&barrier); /* #2 */ + } + + if (arg_private_network) { + + r = move_network_interfaces(pid, arg_network_interfaces); + if (r < 0) + goto finish; + + if (arg_network_veth) { + r = setup_veth(arg_machine, pid, veth_name, + arg_network_bridge || arg_network_zone); + if (r < 0) + goto finish; + else if (r > 0) + ifi = r; + + if (arg_network_bridge) { + /* Add the interface to a bridge */ + r = setup_bridge(veth_name, arg_network_bridge, false); + if (r < 0) + goto finish; + if (r > 0) + ifi = r; + } else if (arg_network_zone) { + /* Add the interface to a bridge, possibly creating it */ + r = setup_bridge(veth_name, arg_network_zone, true); + if (r < 0) + goto finish; + if (r > 0) + ifi = r; + } + } + + r = setup_veth_extra(arg_machine, pid, arg_network_veth_extra); + if (r < 0) + goto finish; + + /* We created the primary and extra veth links now; let's remember this, so that we know to + remove them later on. Note that we don't bother with removing veth links that were created + here when their setup failed half-way, because in that case the kernel should be able to + remove them on its own, since they cannot be referenced by anything yet. */ + veth_created = true; + + r = setup_macvlan(arg_machine, pid, arg_network_macvlan); + if (r < 0) + goto finish; + + r = setup_ipvlan(arg_machine, pid, arg_network_ipvlan); + if (r < 0) + goto finish; + } + + if (arg_register) { + r = register_machine( + arg_machine, + pid, + arg_directory, + arg_uuid, + ifi, + arg_slice, + arg_custom_mounts, arg_n_custom_mounts, + arg_kill_signal, + arg_property, + arg_keep_unit, + arg_container_service_name); + if (r < 0) + goto finish; + } + + r = sync_cgroup(pid, arg_unified_cgroup_hierarchy); + if (r < 0) + goto finish; + + if (arg_keep_unit) { + r = create_subcgroup(pid, arg_unified_cgroup_hierarchy); + if (r < 0) + goto finish; + } + + r = chown_cgroup(pid, arg_uid_shift); + if (r < 0) + goto finish; + + /* Notify the child that the parent is ready with all + * its setup (including cgroup-ification), and that + * the child can now hand over control to the code to + * run inside the container. */ + (void) barrier_place(&barrier); /* #3 */ + + /* Block SIGCHLD here, before notifying child. + * process_pty() will handle it with the other signals. */ + assert_se(sigprocmask(SIG_BLOCK, &mask_chld, NULL) >= 0); + + /* Reset signal to default */ + r = default_signals(SIGCHLD, -1); + if (r < 0) { + log_error_errno(r, "Failed to reset SIGCHLD: %m"); + goto finish; + } + + /* Let the child know that we are ready and wait that the child is completely ready now. */ + if (!barrier_place_and_sync(&barrier)) { /* #4 */ + log_error("Child died too early."); + r = -ESRCH; + goto finish; + } + + /* At this point we have made use of the UID we picked, and thus nss-mymachines will make them appear + * in getpwuid(), thus we can release the /etc/passwd lock. */ + etc_passwd_lock = safe_close(etc_passwd_lock); + + sd_notifyf(false, + "READY=1\n" + "STATUS=Container running.\n" + "X_NSPAWN_LEADER_PID=" PID_FMT, pid); + + r = sd_event_new(&event); + if (r < 0) { + log_error_errno(r, "Failed to get default event source: %m"); + goto finish; + } + + if (arg_kill_signal > 0) { + /* Try to kill the init system on SIGINT or SIGTERM */ + sd_event_add_signal(event, NULL, SIGINT, on_orderly_shutdown, PID_TO_PTR(pid)); + sd_event_add_signal(event, NULL, SIGTERM, on_orderly_shutdown, PID_TO_PTR(pid)); + } else { + /* Immediately exit */ + sd_event_add_signal(event, NULL, SIGINT, NULL, NULL); + sd_event_add_signal(event, NULL, SIGTERM, NULL, NULL); + } + + /* simply exit on sigchld */ + sd_event_add_signal(event, NULL, SIGCHLD, NULL, NULL); + + if (arg_expose_ports) { + r = expose_port_watch_rtnl(event, rtnl_socket_pair[0], on_address_change, &exposed, &rtnl); + if (r < 0) + goto finish; + + (void) expose_port_execute(rtnl, arg_expose_ports, &exposed); + } + + rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]); + + r = pty_forward_new(event, master, PTY_FORWARD_IGNORE_VHANGUP | (interactive ? 0 : PTY_FORWARD_READ_ONLY), &forward); + if (r < 0) { + log_error_errno(r, "Failed to create PTY forwarder: %m"); + goto finish; + } + + r = sd_event_loop(event); + if (r < 0) { + log_error_errno(r, "Failed to run event loop: %m"); + goto finish; + } + + pty_forward_get_last_char(forward, &last_char); + + forward = pty_forward_free(forward); + + if (!arg_quiet && last_char != '\n') + putc('\n', stdout); + + /* Kill if it is not dead yet anyway */ + if (arg_register && !arg_keep_unit) + terminate_machine(pid); + + /* Normally redundant, but better safe than sorry */ + kill(pid, SIGKILL); + + r = wait_for_container(pid, &container_status); + pid = 0; + + if (r < 0) + /* We failed to wait for the container, or the + * container exited abnormally */ + goto finish; + else if (r > 0 || container_status == CONTAINER_TERMINATED) { + /* The container exited with a non-zero + * status, or with zero status and no reboot + * was requested. */ + ret = r; + break; + } + + /* CONTAINER_REBOOTED, loop again */ + + if (arg_keep_unit) { + /* Special handling if we are running as a + * service: instead of simply restarting the + * machine we want to restart the entire + * service, so let's inform systemd about this + * with the special exit code 133. The service + * file uses RestartForceExitStatus=133 so + * that this results in a full nspawn + * restart. This is necessary since we might + * have cgroup parameters set we want to have + * flushed out. */ + ret = 133; + r = 0; + break; + } + + expose_port_flush(arg_expose_ports, &exposed); + + (void) remove_veth_links(veth_name, arg_network_veth_extra); + veth_created = false; + } + +finish: + sd_notify(false, + "STOPPING=1\n" + "STATUS=Terminating..."); + + if (pid > 0) + kill(pid, SIGKILL); + + /* Try to flush whatever is still queued in the pty */ + if (master >= 0) + (void) copy_bytes(master, STDOUT_FILENO, (uint64_t) -1, false); + + loop_remove(loop_nr, &image_fd); + + if (remove_subvol && arg_directory) { + int k; + + k = btrfs_subvol_remove(arg_directory, BTRFS_REMOVE_RECURSIVE|BTRFS_REMOVE_QUOTA); + if (k < 0) + log_warning_errno(k, "Cannot remove subvolume '%s', ignoring: %m", arg_directory); + } + + if (arg_machine) { + const char *p; + + p = strjoina("/run/systemd/nspawn/propagate/", arg_machine); + (void) rm_rf(p, REMOVE_ROOT); + } + + expose_port_flush(arg_expose_ports, &exposed); + + if (veth_created) + (void) remove_veth_links(veth_name, arg_network_veth_extra); + (void) remove_bridge(arg_network_zone); + + free(arg_directory); + free(arg_template); + free(arg_image); + free(arg_machine); + free(arg_user); + free(arg_chdir); + strv_free(arg_setenv); + free(arg_network_bridge); + strv_free(arg_network_interfaces); + strv_free(arg_network_macvlan); + strv_free(arg_network_ipvlan); + strv_free(arg_network_veth_extra); + strv_free(arg_parameters); + custom_mount_free_all(arg_custom_mounts, arg_n_custom_mounts); + expose_port_free_all(arg_expose_ports); + + return r < 0 ? EXIT_FAILURE : ret; +} diff --git a/src/systemd-nspawn/test-patch-uid.c b/src/systemd-nspawn/test-patch-uid.c new file mode 100644 index 0000000000..11c5321788 --- /dev/null +++ b/src/systemd-nspawn/test-patch-uid.c @@ -0,0 +1,61 @@ +/*** + This file is part of systemd. + + Copyright 2016 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 <stdlib.h> + +#include "log.h" +#include "nspawn-patch-uid.h" +#include "user-util.h" +#include "util.h" + +int main(int argc, char *argv[]) { + uid_t shift, range; + int r; + + log_set_max_level(LOG_DEBUG); + log_parse_environment(); + log_open(); + + if (argc != 4) { + log_error("Expected PATH SHIFT RANGE parameters."); + return EXIT_FAILURE; + } + + r = parse_uid(argv[2], &shift); + if (r < 0) { + log_error_errno(r, "Failed to parse UID shift %s.", argv[2]); + return EXIT_FAILURE; + } + + r = parse_gid(argv[3], &range); + if (r < 0) { + log_error_errno(r, "Failed to parse UID range %s.", argv[3]); + return EXIT_FAILURE; + } + + r = path_patch_uid(argv[1], shift, range); + if (r < 0) { + log_error_errno(r, "Failed to patch directory tree: %m"); + return EXIT_FAILURE; + } + + log_info("Changed: %s", yes_no(r)); + + return EXIT_SUCCESS; +} |