1485 lines
49 KiB
C
1485 lines
49 KiB
C
/* SPDX-License-Identifier: LGPL-2.1+ */
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/***
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This file is part of systemd.
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Copyright 2010 Lennart Poettering
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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***/
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#include <errno.h>
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#include <sched.h>
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#include <stdio.h>
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#include <string.h>
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#include <sys/mount.h>
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#include <sys/stat.h>
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#include <unistd.h>
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#include <linux/fs.h>
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#include "alloc-util.h"
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#include "base-filesystem.h"
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#include "dev-setup.h"
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#include "fd-util.h"
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#include "fs-util.h"
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#include "label.h"
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#include "loop-util.h"
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#include "loopback-setup.h"
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#include "missing.h"
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#include "mkdir.h"
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#include "mount-util.h"
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#include "namespace.h"
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#include "path-util.h"
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#include "selinux-util.h"
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#include "socket-util.h"
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#include "string-table.h"
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#include "string-util.h"
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#include "strv.h"
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#include "umask-util.h"
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#include "user-util.h"
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#include "util.h"
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#define DEV_MOUNT_OPTIONS (MS_NOSUID|MS_STRICTATIME|MS_NOEXEC)
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typedef enum MountMode {
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/* This is ordered by priority! */
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INACCESSIBLE,
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BIND_MOUNT,
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BIND_MOUNT_RECURSIVE,
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PRIVATE_TMP,
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PRIVATE_VAR_TMP,
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PRIVATE_DEV,
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BIND_DEV,
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EMPTY_DIR,
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SYSFS,
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PROCFS,
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READONLY,
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READWRITE,
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} MountMode;
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typedef struct MountEntry {
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const char *path_const; /* Memory allocated on stack or static */
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MountMode mode:5;
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bool ignore:1; /* Ignore if path does not exist? */
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bool has_prefix:1; /* Already is prefixed by the root dir? */
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bool read_only:1; /* Shall this mount point be read-only? */
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char *path_malloc; /* Use this instead of 'path' if we had to allocate memory */
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const char *source_const; /* The source path, for bind mounts */
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char *source_malloc;
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} MountEntry;
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/* If MountAPIVFS= is used, let's mount /sys and /proc into the it, but only as a fallback if the user hasn't mounted
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* something there already. These mounts are hence overriden by any other explicitly configured mounts. */
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static const MountEntry apivfs_table[] = {
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{ "/proc", PROCFS, false },
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{ "/dev", BIND_DEV, false },
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{ "/sys", SYSFS, false },
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};
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/* ProtectKernelTunables= option and the related filesystem APIs */
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static const MountEntry protect_kernel_tunables_table[] = {
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{ "/proc/sys", READONLY, false },
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{ "/proc/sysrq-trigger", READONLY, true },
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{ "/proc/latency_stats", READONLY, true },
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{ "/proc/mtrr", READONLY, true },
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{ "/proc/apm", READONLY, true }, /* Obsolete API, there's no point in permitting access to this, ever */
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{ "/proc/acpi", READONLY, true },
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{ "/proc/timer_stats", READONLY, true },
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{ "/proc/asound", READONLY, true },
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{ "/proc/bus", READONLY, true },
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{ "/proc/fs", READONLY, true },
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{ "/proc/irq", READONLY, true },
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{ "/sys", READONLY, false },
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{ "/sys/kernel/debug", READONLY, true },
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{ "/sys/kernel/tracing", READONLY, true },
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{ "/sys/fs/cgroup", READWRITE, false }, /* READONLY is set by ProtectControlGroups= option */
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{ "/sys/fs/selinux", READWRITE, true },
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};
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/* ProtectKernelModules= option */
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static const MountEntry protect_kernel_modules_table[] = {
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#if HAVE_SPLIT_USR
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{ "/lib/modules", INACCESSIBLE, true },
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#endif
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{ "/usr/lib/modules", INACCESSIBLE, true },
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};
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/*
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* ProtectHome=read-only table, protect $HOME and $XDG_RUNTIME_DIR and rest of
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* system should be protected by ProtectSystem=
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*/
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static const MountEntry protect_home_read_only_table[] = {
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{ "/home", READONLY, true },
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{ "/run/user", READONLY, true },
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{ "/root", READONLY, true },
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};
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/* ProtectHome=yes table */
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static const MountEntry protect_home_yes_table[] = {
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{ "/home", INACCESSIBLE, true },
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{ "/run/user", INACCESSIBLE, true },
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{ "/root", INACCESSIBLE, true },
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};
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/* ProtectSystem=yes table */
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static const MountEntry protect_system_yes_table[] = {
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{ "/usr", READONLY, false },
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{ "/boot", READONLY, true },
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{ "/efi", READONLY, true },
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};
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/* ProtectSystem=full includes ProtectSystem=yes */
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static const MountEntry protect_system_full_table[] = {
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{ "/usr", READONLY, false },
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{ "/boot", READONLY, true },
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{ "/efi", READONLY, true },
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{ "/etc", READONLY, false },
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};
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/*
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* ProtectSystem=strict table. In this strict mode, we mount everything
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* read-only, except for /proc, /dev, /sys which are the kernel API VFS,
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* which are left writable, but PrivateDevices= + ProtectKernelTunables=
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* protect those, and these options should be fully orthogonal.
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* (And of course /home and friends are also left writable, as ProtectHome=
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* shall manage those, orthogonally).
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*/
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static const MountEntry protect_system_strict_table[] = {
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{ "/", READONLY, false },
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{ "/proc", READWRITE, false }, /* ProtectKernelTunables= */
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{ "/sys", READWRITE, false }, /* ProtectKernelTunables= */
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{ "/dev", READWRITE, false }, /* PrivateDevices= */
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{ "/home", READWRITE, true }, /* ProtectHome= */
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{ "/run/user", READWRITE, true }, /* ProtectHome= */
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{ "/root", READWRITE, true }, /* ProtectHome= */
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};
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static const char *mount_entry_path(const MountEntry *p) {
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assert(p);
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/* Returns the path of this bind mount. If the malloc()-allocated ->path_buffer field is set we return that,
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* otherwise the stack/static ->path field is returned. */
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return p->path_malloc ?: p->path_const;
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}
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static bool mount_entry_read_only(const MountEntry *p) {
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assert(p);
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return p->read_only || IN_SET(p->mode, READONLY, INACCESSIBLE);
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}
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static const char *mount_entry_source(const MountEntry *p) {
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assert(p);
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return p->source_malloc ?: p->source_const;
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}
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static void mount_entry_done(MountEntry *p) {
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assert(p);
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p->path_malloc = mfree(p->path_malloc);
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p->source_malloc = mfree(p->source_malloc);
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}
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static int append_access_mounts(MountEntry **p, char **strv, MountMode mode, bool forcibly_require_prefix) {
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char **i;
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assert(p);
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/* Adds a list of user-supplied READWRITE/READONLY/INACCESSIBLE entries */
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STRV_FOREACH(i, strv) {
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bool ignore = false, needs_prefix = false;
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const char *e = *i;
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/* Look for any prefixes */
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if (startswith(e, "-")) {
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e++;
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ignore = true;
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}
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if (startswith(e, "+")) {
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e++;
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needs_prefix = true;
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}
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if (!path_is_absolute(e))
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return -EINVAL;
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*((*p)++) = (MountEntry) {
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.path_const = e,
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.mode = mode,
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.ignore = ignore,
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.has_prefix = !needs_prefix && !forcibly_require_prefix,
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};
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}
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return 0;
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}
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static int append_empty_dir_mounts(MountEntry **p, char **strv) {
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char **i;
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assert(p);
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/* Adds tmpfs mounts to provide readable but empty directories. This is primarily used to implement the
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* "/private/" boundary directories for DynamicUser=1. */
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STRV_FOREACH(i, strv) {
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*((*p)++) = (MountEntry) {
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.path_const = *i,
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.mode = EMPTY_DIR,
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.ignore = false,
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.has_prefix = false,
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.read_only = true,
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};
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}
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return 0;
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}
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static int append_bind_mounts(MountEntry **p, const BindMount *binds, unsigned n) {
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unsigned i;
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assert(p);
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for (i = 0; i < n; i++) {
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const BindMount *b = binds + i;
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*((*p)++) = (MountEntry) {
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.path_const = b->destination,
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.mode = b->recursive ? BIND_MOUNT_RECURSIVE : BIND_MOUNT,
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.read_only = b->read_only,
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.source_const = b->source,
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};
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}
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return 0;
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}
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static int append_static_mounts(MountEntry **p, const MountEntry *mounts, unsigned n, bool ignore_protect) {
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unsigned i;
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assert(p);
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assert(mounts);
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/* Adds a list of static pre-defined entries */
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for (i = 0; i < n; i++)
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*((*p)++) = (MountEntry) {
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.path_const = mount_entry_path(mounts+i),
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.mode = mounts[i].mode,
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.ignore = mounts[i].ignore || ignore_protect,
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};
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return 0;
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}
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static int append_protect_home(MountEntry **p, ProtectHome protect_home, bool ignore_protect) {
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assert(p);
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switch (protect_home) {
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case PROTECT_HOME_NO:
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return 0;
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case PROTECT_HOME_READ_ONLY:
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return append_static_mounts(p, protect_home_read_only_table, ELEMENTSOF(protect_home_read_only_table), ignore_protect);
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case PROTECT_HOME_YES:
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return append_static_mounts(p, protect_home_yes_table, ELEMENTSOF(protect_home_yes_table), ignore_protect);
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default:
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assert_not_reached("Unexpected ProtectHome= value");
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}
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}
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static int append_protect_system(MountEntry **p, ProtectSystem protect_system, bool ignore_protect) {
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assert(p);
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switch (protect_system) {
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case PROTECT_SYSTEM_NO:
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return 0;
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case PROTECT_SYSTEM_STRICT:
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return append_static_mounts(p, protect_system_strict_table, ELEMENTSOF(protect_system_strict_table), ignore_protect);
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case PROTECT_SYSTEM_YES:
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return append_static_mounts(p, protect_system_yes_table, ELEMENTSOF(protect_system_yes_table), ignore_protect);
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case PROTECT_SYSTEM_FULL:
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return append_static_mounts(p, protect_system_full_table, ELEMENTSOF(protect_system_full_table), ignore_protect);
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default:
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assert_not_reached("Unexpected ProtectSystem= value");
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}
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}
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static int mount_path_compare(const void *a, const void *b) {
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const MountEntry *p = a, *q = b;
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int d;
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/* If the paths are not equal, then order prefixes first */
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d = path_compare(mount_entry_path(p), mount_entry_path(q));
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if (d != 0)
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return d;
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/* If the paths are equal, check the mode */
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if (p->mode < q->mode)
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return -1;
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if (p->mode > q->mode)
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return 1;
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return 0;
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}
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static int prefix_where_needed(MountEntry *m, unsigned n, const char *root_directory) {
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unsigned i;
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/* Prefixes all paths in the bind mount table with the root directory if it is specified and the entry needs
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* that. */
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if (!root_directory)
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return 0;
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for (i = 0; i < n; i++) {
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char *s;
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if (m[i].has_prefix)
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continue;
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s = prefix_root(root_directory, mount_entry_path(m+i));
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if (!s)
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return -ENOMEM;
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free(m[i].path_malloc);
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m[i].path_malloc = s;
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m[i].has_prefix = true;
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}
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return 0;
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}
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static void drop_duplicates(MountEntry *m, unsigned *n) {
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MountEntry *f, *t, *previous;
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assert(m);
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assert(n);
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/* Drops duplicate entries. Expects that the array is properly ordered already. */
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for (f = m, t = m, previous = NULL; f < m + *n; f++) {
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/* The first one wins (which is the one with the more restrictive mode), see mount_path_compare()
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* above. */
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if (previous && path_equal(mount_entry_path(f), mount_entry_path(previous))) {
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log_debug("%s is duplicate.", mount_entry_path(f));
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previous->read_only = previous->read_only || mount_entry_read_only(f); /* Propagate the read-only flag to the remaining entry */
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mount_entry_done(f);
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continue;
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}
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*t = *f;
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previous = t;
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t++;
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}
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*n = t - m;
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}
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static void drop_inaccessible(MountEntry *m, unsigned *n) {
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MountEntry *f, *t;
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const char *clear = NULL;
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assert(m);
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assert(n);
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/* Drops all entries obstructed by another entry further up the tree. Expects that the array is properly
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* ordered already. */
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for (f = m, t = m; f < m + *n; f++) {
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/* If we found a path set for INACCESSIBLE earlier, and this entry has it as prefix we should drop
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* it, as inaccessible paths really should drop the entire subtree. */
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if (clear && path_startswith(mount_entry_path(f), clear)) {
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log_debug("%s is masked by %s.", mount_entry_path(f), clear);
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mount_entry_done(f);
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continue;
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}
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clear = f->mode == INACCESSIBLE ? mount_entry_path(f) : NULL;
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*t = *f;
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t++;
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}
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*n = t - m;
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}
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static void drop_nop(MountEntry *m, unsigned *n) {
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MountEntry *f, *t;
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assert(m);
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assert(n);
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|
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/* Drops all entries which have an immediate parent that has the same type, as they are redundant. Assumes the
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* list is ordered by prefixes. */
|
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for (f = m, t = m; f < m + *n; f++) {
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|
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/* Only suppress such subtrees for READONLY and READWRITE entries */
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if (IN_SET(f->mode, READONLY, READWRITE)) {
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MountEntry *p;
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bool found = false;
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|
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/* Now let's find the first parent of the entry we are looking at. */
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for (p = t-1; p >= m; p--) {
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if (path_startswith(mount_entry_path(f), mount_entry_path(p))) {
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found = true;
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break;
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}
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}
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|
|
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/* We found it, let's see if it's the same mode, if so, we can drop this entry */
|
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if (found && p->mode == f->mode) {
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log_debug("%s is redundant by %s", mount_entry_path(f), mount_entry_path(p));
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mount_entry_done(f);
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continue;
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}
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}
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|
|
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*t = *f;
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t++;
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}
|
|
|
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*n = t - m;
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}
|
|
|
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static void drop_outside_root(const char *root_directory, MountEntry *m, unsigned *n) {
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MountEntry *f, *t;
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|
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assert(m);
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assert(n);
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|
|
|
/* Nothing to do */
|
|
if (!root_directory)
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|
return;
|
|
|
|
/* Drops all mounts that are outside of the root directory. */
|
|
|
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for (f = m, t = m; f < m + *n; f++) {
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if (!path_startswith(mount_entry_path(f), root_directory)) {
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|
log_debug("%s is outside of root directory.", mount_entry_path(f));
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|
mount_entry_done(f);
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continue;
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|
}
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|
|
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*t = *f;
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|
t++;
|
|
}
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|
|
*n = t - m;
|
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}
|
|
|
|
static int mount_private_dev(MountEntry *m) {
|
|
static const char devnodes[] =
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"/dev/null\0"
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|
"/dev/zero\0"
|
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"/dev/full\0"
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"/dev/random\0"
|
|
"/dev/urandom\0"
|
|
"/dev/tty\0";
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|
|
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char temporary_mount[] = "/tmp/namespace-dev-XXXXXX";
|
|
const char *d, *dev = NULL, *devpts = NULL, *devshm = NULL, *devhugepages = NULL, *devmqueue = NULL, *devlog = NULL, *devptmx = NULL;
|
|
_cleanup_umask_ mode_t u;
|
|
int r;
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|
|
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assert(m);
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|
|
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u = umask(0000);
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|
|
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if (!mkdtemp(temporary_mount))
|
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return -errno;
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|
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dev = strjoina(temporary_mount, "/dev");
|
|
(void) mkdir(dev, 0755);
|
|
if (mount("tmpfs", dev, "tmpfs", DEV_MOUNT_OPTIONS, "mode=755") < 0) {
|
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r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
devpts = strjoina(temporary_mount, "/dev/pts");
|
|
(void) mkdir(devpts, 0755);
|
|
if (mount("/dev/pts", devpts, NULL, MS_BIND, NULL) < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
devptmx = strjoina(temporary_mount, "/dev/ptmx");
|
|
if (symlink("pts/ptmx", devptmx) < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
devshm = strjoina(temporary_mount, "/dev/shm");
|
|
(void) mkdir(devshm, 01777);
|
|
r = mount("/dev/shm", devshm, NULL, MS_BIND, NULL);
|
|
if (r < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
devmqueue = strjoina(temporary_mount, "/dev/mqueue");
|
|
(void) mkdir(devmqueue, 0755);
|
|
(void) mount("/dev/mqueue", devmqueue, NULL, MS_BIND, NULL);
|
|
|
|
devhugepages = strjoina(temporary_mount, "/dev/hugepages");
|
|
(void) mkdir(devhugepages, 0755);
|
|
(void) mount("/dev/hugepages", devhugepages, NULL, MS_BIND, NULL);
|
|
|
|
devlog = strjoina(temporary_mount, "/dev/log");
|
|
(void) symlink("/run/systemd/journal/dev-log", devlog);
|
|
|
|
NULSTR_FOREACH(d, devnodes) {
|
|
_cleanup_free_ char *dn = NULL;
|
|
struct stat st;
|
|
|
|
r = stat(d, &st);
|
|
if (r < 0) {
|
|
|
|
if (errno == ENOENT)
|
|
continue;
|
|
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
if (!S_ISBLK(st.st_mode) &&
|
|
!S_ISCHR(st.st_mode)) {
|
|
r = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
if (st.st_rdev == 0)
|
|
continue;
|
|
|
|
dn = strappend(temporary_mount, d);
|
|
if (!dn) {
|
|
r = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
mac_selinux_create_file_prepare(d, st.st_mode);
|
|
r = mknod(dn, st.st_mode, st.st_rdev);
|
|
mac_selinux_create_file_clear();
|
|
|
|
if (r < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
dev_setup(temporary_mount, UID_INVALID, GID_INVALID);
|
|
|
|
/* Create the /dev directory if missing. It is more likely to be
|
|
* missing when the service is started with RootDirectory. This is
|
|
* consistent with mount units creating the mount points when missing.
|
|
*/
|
|
(void) mkdir_p_label(mount_entry_path(m), 0755);
|
|
|
|
/* Unmount everything in old /dev */
|
|
umount_recursive(mount_entry_path(m), 0);
|
|
if (mount(dev, mount_entry_path(m), NULL, MS_MOVE, NULL) < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
rmdir(dev);
|
|
rmdir(temporary_mount);
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
if (devpts)
|
|
umount(devpts);
|
|
|
|
if (devshm)
|
|
umount(devshm);
|
|
|
|
if (devhugepages)
|
|
umount(devhugepages);
|
|
|
|
if (devmqueue)
|
|
umount(devmqueue);
|
|
|
|
umount(dev);
|
|
rmdir(dev);
|
|
rmdir(temporary_mount);
|
|
|
|
return r;
|
|
}
|
|
|
|
static int mount_bind_dev(MountEntry *m) {
|
|
int r;
|
|
|
|
assert(m);
|
|
|
|
/* Implements the little brother of mount_private_dev(): simply bind mounts the host's /dev into the service's
|
|
* /dev. This is only used when RootDirectory= is set. */
|
|
|
|
(void) mkdir_p_label(mount_entry_path(m), 0755);
|
|
|
|
r = path_is_mount_point(mount_entry_path(m), NULL, 0);
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Unable to determine whether /dev is already mounted: %m");
|
|
if (r > 0) /* make this a NOP if /dev is already a mount point */
|
|
return 0;
|
|
|
|
if (mount("/dev", mount_entry_path(m), NULL, MS_BIND|MS_REC, NULL) < 0)
|
|
return log_debug_errno(errno, "Failed to bind mount %s: %m", mount_entry_path(m));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int mount_sysfs(MountEntry *m) {
|
|
int r;
|
|
|
|
assert(m);
|
|
|
|
(void) mkdir_p_label(mount_entry_path(m), 0755);
|
|
|
|
r = path_is_mount_point(mount_entry_path(m), NULL, 0);
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Unable to determine whether /sys is already mounted: %m");
|
|
if (r > 0) /* make this a NOP if /sys is already a mount point */
|
|
return 0;
|
|
|
|
/* Bind mount the host's version so that we get all child mounts of it, too. */
|
|
if (mount("/sys", mount_entry_path(m), NULL, MS_BIND|MS_REC, NULL) < 0)
|
|
return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int mount_procfs(MountEntry *m) {
|
|
int r;
|
|
|
|
assert(m);
|
|
|
|
(void) mkdir_p_label(mount_entry_path(m), 0755);
|
|
|
|
r = path_is_mount_point(mount_entry_path(m), NULL, 0);
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Unable to determine whether /proc is already mounted: %m");
|
|
if (r > 0) /* make this a NOP if /proc is already a mount point */
|
|
return 0;
|
|
|
|
/* Mount a new instance, so that we get the one that matches our user namespace, if we are running in one */
|
|
if (mount("proc", mount_entry_path(m), "proc", MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) < 0)
|
|
return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int mount_empty_dir(MountEntry *m) {
|
|
assert(m);
|
|
|
|
/* First, get rid of everything that is below if there is anything. Then, overmount with our new empty dir */
|
|
|
|
(void) mkdir_p_label(mount_entry_path(m), 0755);
|
|
(void) umount_recursive(mount_entry_path(m), 0);
|
|
|
|
if (mount("tmpfs", mount_entry_path(m), "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, "mode=755") < 0)
|
|
return log_debug_errno(errno, "Failed to mount %s: %m", mount_entry_path(m));
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int mount_entry_chase(
|
|
const char *root_directory,
|
|
MountEntry *m,
|
|
const char *path,
|
|
char **location) {
|
|
|
|
char *chased;
|
|
int r;
|
|
|
|
assert(m);
|
|
|
|
/* Since mount() will always follow symlinks and we need to take the different root directory into account we
|
|
* chase the symlinks on our own first. This is called for the destination path, as well as the source path (if
|
|
* that applies). The result is stored in "location". */
|
|
|
|
r = chase_symlinks(path, root_directory,
|
|
IN_SET(m->mode, BIND_MOUNT, BIND_MOUNT_RECURSIVE, PRIVATE_TMP, PRIVATE_VAR_TMP, PRIVATE_DEV, BIND_DEV, EMPTY_DIR, SYSFS, PROCFS) ? CHASE_NONEXISTENT : 0,
|
|
&chased);
|
|
if (r == -ENOENT && m->ignore) {
|
|
log_debug_errno(r, "Path %s does not exist, ignoring.", path);
|
|
return 0;
|
|
}
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Failed to follow symlinks on %s: %m", path);
|
|
|
|
log_debug("Followed symlinks %s → %s.", path, chased);
|
|
|
|
free(*location);
|
|
*location = chased;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static int apply_mount(
|
|
const char *root_directory,
|
|
MountEntry *m,
|
|
const char *tmp_dir,
|
|
const char *var_tmp_dir) {
|
|
|
|
bool rbind = true, make = false;
|
|
const char *what;
|
|
int r;
|
|
|
|
assert(m);
|
|
|
|
r = mount_entry_chase(root_directory, m, mount_entry_path(m), &m->path_malloc);
|
|
if (r <= 0)
|
|
return r;
|
|
|
|
log_debug("Applying namespace mount on %s", mount_entry_path(m));
|
|
|
|
switch (m->mode) {
|
|
|
|
case INACCESSIBLE: {
|
|
struct stat target;
|
|
|
|
/* First, get rid of everything that is below if there
|
|
* is anything... Then, overmount it with an
|
|
* inaccessible path. */
|
|
(void) umount_recursive(mount_entry_path(m), 0);
|
|
|
|
if (lstat(mount_entry_path(m), &target) < 0)
|
|
return log_debug_errno(errno, "Failed to lstat() %s to determine what to mount over it: %m", mount_entry_path(m));
|
|
|
|
what = mode_to_inaccessible_node(target.st_mode);
|
|
if (!what) {
|
|
log_debug("File type not supported for inaccessible mounts. Note that symlinks are not allowed");
|
|
return -ELOOP;
|
|
}
|
|
break;
|
|
}
|
|
|
|
case READONLY:
|
|
case READWRITE:
|
|
r = path_is_mount_point(mount_entry_path(m), root_directory, 0);
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Failed to determine whether %s is already a mount point: %m", mount_entry_path(m));
|
|
if (r > 0) /* Nothing to do here, it is already a mount. We just later toggle the MS_RDONLY bit for the mount point if needed. */
|
|
return 0;
|
|
/* This isn't a mount point yet, let's make it one. */
|
|
what = mount_entry_path(m);
|
|
break;
|
|
|
|
case BIND_MOUNT:
|
|
rbind = false;
|
|
|
|
_fallthrough_;
|
|
case BIND_MOUNT_RECURSIVE:
|
|
/* Also chase the source mount */
|
|
|
|
r = mount_entry_chase(root_directory, m, mount_entry_source(m), &m->source_malloc);
|
|
if (r <= 0)
|
|
return r;
|
|
|
|
what = mount_entry_source(m);
|
|
make = true;
|
|
break;
|
|
|
|
case EMPTY_DIR:
|
|
return mount_empty_dir(m);
|
|
|
|
case PRIVATE_TMP:
|
|
what = tmp_dir;
|
|
make = true;
|
|
break;
|
|
|
|
case PRIVATE_VAR_TMP:
|
|
what = var_tmp_dir;
|
|
make = true;
|
|
break;
|
|
|
|
case PRIVATE_DEV:
|
|
return mount_private_dev(m);
|
|
|
|
case BIND_DEV:
|
|
return mount_bind_dev(m);
|
|
|
|
case SYSFS:
|
|
return mount_sysfs(m);
|
|
|
|
case PROCFS:
|
|
return mount_procfs(m);
|
|
|
|
default:
|
|
assert_not_reached("Unknown mode");
|
|
}
|
|
|
|
assert(what);
|
|
|
|
if (mount(what, mount_entry_path(m), NULL, MS_BIND|(rbind ? MS_REC : 0), NULL) < 0) {
|
|
bool try_again = false;
|
|
r = -errno;
|
|
|
|
if (r == -ENOENT && make) {
|
|
struct stat st;
|
|
|
|
/* Hmm, either the source or the destination are missing. Let's see if we can create the destination, then try again */
|
|
|
|
if (stat(what, &st) >= 0) {
|
|
|
|
(void) mkdir_parents(mount_entry_path(m), 0755);
|
|
|
|
if (S_ISDIR(st.st_mode))
|
|
try_again = mkdir(mount_entry_path(m), 0755) >= 0;
|
|
else
|
|
try_again = touch(mount_entry_path(m)) >= 0;
|
|
}
|
|
}
|
|
|
|
if (try_again) {
|
|
if (mount(what, mount_entry_path(m), NULL, MS_BIND|(rbind ? MS_REC : 0), NULL) < 0)
|
|
r = -errno;
|
|
else
|
|
r = 0;
|
|
}
|
|
|
|
if (r < 0)
|
|
return log_debug_errno(r, "Failed to mount %s to %s: %m", what, mount_entry_path(m));
|
|
}
|
|
|
|
log_debug("Successfully mounted %s to %s", what, mount_entry_path(m));
|
|
return 0;
|
|
}
|
|
|
|
static int make_read_only(MountEntry *m, char **blacklist, FILE *proc_self_mountinfo) {
|
|
int r = 0;
|
|
|
|
assert(m);
|
|
assert(proc_self_mountinfo);
|
|
|
|
if (mount_entry_read_only(m))
|
|
r = bind_remount_recursive_with_mountinfo(mount_entry_path(m), true, blacklist, proc_self_mountinfo);
|
|
else if (m->mode == PRIVATE_DEV) { /* Superblock can be readonly but the submounts can't */
|
|
if (mount(NULL, mount_entry_path(m), NULL, MS_REMOUNT|DEV_MOUNT_OPTIONS|MS_RDONLY, NULL) < 0)
|
|
r = -errno;
|
|
} else
|
|
return 0;
|
|
|
|
/* Not that we only turn on the MS_RDONLY flag here, we never turn it off. Something that was marked read-only
|
|
* already stays this way. This improves compatibility with container managers, where we won't attempt to undo
|
|
* read-only mounts already applied. */
|
|
|
|
if (r == -ENOENT && m->ignore)
|
|
r = 0;
|
|
|
|
return r;
|
|
}
|
|
|
|
static bool namespace_info_mount_apivfs(const char *root_directory, const NamespaceInfo *ns_info) {
|
|
assert(ns_info);
|
|
|
|
/*
|
|
* ProtectControlGroups= and ProtectKernelTunables= imply MountAPIVFS=,
|
|
* since to protect the API VFS mounts, they need to be around in the
|
|
* first place... and RootDirectory= or RootImage= need to be set.
|
|
*/
|
|
|
|
/* root_directory should point to a mount point */
|
|
return root_directory &&
|
|
(ns_info->mount_apivfs ||
|
|
ns_info->protect_control_groups ||
|
|
ns_info->protect_kernel_tunables);
|
|
}
|
|
|
|
static unsigned namespace_calculate_mounts(
|
|
const char* root_directory,
|
|
const NamespaceInfo *ns_info,
|
|
char** read_write_paths,
|
|
char** read_only_paths,
|
|
char** inaccessible_paths,
|
|
char** empty_directories,
|
|
const BindMount *bind_mounts,
|
|
unsigned n_bind_mounts,
|
|
const char* tmp_dir,
|
|
const char* var_tmp_dir,
|
|
ProtectHome protect_home,
|
|
ProtectSystem protect_system) {
|
|
|
|
unsigned protect_home_cnt;
|
|
unsigned protect_system_cnt =
|
|
(protect_system == PROTECT_SYSTEM_STRICT ?
|
|
ELEMENTSOF(protect_system_strict_table) :
|
|
((protect_system == PROTECT_SYSTEM_FULL) ?
|
|
ELEMENTSOF(protect_system_full_table) :
|
|
((protect_system == PROTECT_SYSTEM_YES) ?
|
|
ELEMENTSOF(protect_system_yes_table) : 0)));
|
|
|
|
protect_home_cnt =
|
|
(protect_home == PROTECT_HOME_YES ?
|
|
ELEMENTSOF(protect_home_yes_table) :
|
|
((protect_home == PROTECT_HOME_READ_ONLY) ?
|
|
ELEMENTSOF(protect_home_read_only_table) : 0));
|
|
|
|
return !!tmp_dir + !!var_tmp_dir +
|
|
strv_length(read_write_paths) +
|
|
strv_length(read_only_paths) +
|
|
strv_length(inaccessible_paths) +
|
|
strv_length(empty_directories) +
|
|
n_bind_mounts +
|
|
ns_info->private_dev +
|
|
(ns_info->protect_kernel_tunables ? ELEMENTSOF(protect_kernel_tunables_table) : 0) +
|
|
(ns_info->protect_control_groups ? 1 : 0) +
|
|
(ns_info->protect_kernel_modules ? ELEMENTSOF(protect_kernel_modules_table) : 0) +
|
|
protect_home_cnt + protect_system_cnt +
|
|
(namespace_info_mount_apivfs(root_directory, ns_info) ? ELEMENTSOF(apivfs_table) : 0);
|
|
}
|
|
|
|
int setup_namespace(
|
|
const char* root_directory,
|
|
const char* root_image,
|
|
const NamespaceInfo *ns_info,
|
|
char** read_write_paths,
|
|
char** read_only_paths,
|
|
char** inaccessible_paths,
|
|
char** empty_directories,
|
|
const BindMount *bind_mounts,
|
|
unsigned n_bind_mounts,
|
|
const char* tmp_dir,
|
|
const char* var_tmp_dir,
|
|
ProtectHome protect_home,
|
|
ProtectSystem protect_system,
|
|
unsigned long mount_flags,
|
|
DissectImageFlags dissect_image_flags) {
|
|
|
|
_cleanup_(loop_device_unrefp) LoopDevice *loop_device = NULL;
|
|
_cleanup_(decrypted_image_unrefp) DecryptedImage *decrypted_image = NULL;
|
|
_cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL;
|
|
_cleanup_free_ void *root_hash = NULL;
|
|
MountEntry *m, *mounts = NULL;
|
|
size_t root_hash_size = 0;
|
|
bool make_slave = false;
|
|
const char *root;
|
|
unsigned n_mounts;
|
|
bool require_prefix = false;
|
|
int r = 0;
|
|
|
|
assert(ns_info);
|
|
|
|
if (mount_flags == 0)
|
|
mount_flags = MS_SHARED;
|
|
|
|
if (root_image) {
|
|
dissect_image_flags |= DISSECT_IMAGE_REQUIRE_ROOT;
|
|
|
|
if (protect_system == PROTECT_SYSTEM_STRICT && strv_isempty(read_write_paths))
|
|
dissect_image_flags |= DISSECT_IMAGE_READ_ONLY;
|
|
|
|
r = loop_device_make_by_path(root_image,
|
|
dissect_image_flags & DISSECT_IMAGE_READ_ONLY ? O_RDONLY : O_RDWR,
|
|
&loop_device);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = root_hash_load(root_image, &root_hash, &root_hash_size);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dissect_image(loop_device->fd, root_hash, root_hash_size, dissect_image_flags, &dissected_image);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = dissected_image_decrypt(dissected_image, NULL, root_hash, root_hash_size, dissect_image_flags, &decrypted_image);
|
|
if (r < 0)
|
|
return r;
|
|
}
|
|
|
|
if (root_directory)
|
|
root = root_directory;
|
|
else if (root_image || n_bind_mounts > 0) {
|
|
|
|
/* If we are booting from an image, create a mount point for the image, if it's still missing. We use
|
|
* the same mount point for all images, which is safe, since they all live in their own namespaces
|
|
* after all, and hence won't see each other. We also use such a root directory whenever there are bind
|
|
* mounts configured, so that their source mounts are never obstructed by mounts we already applied
|
|
* while we are applying them. */
|
|
|
|
root = "/run/systemd/unit-root";
|
|
(void) mkdir_label(root, 0700);
|
|
require_prefix = true;
|
|
} else
|
|
root = NULL;
|
|
|
|
n_mounts = namespace_calculate_mounts(
|
|
root,
|
|
ns_info,
|
|
read_write_paths,
|
|
read_only_paths,
|
|
inaccessible_paths,
|
|
empty_directories,
|
|
bind_mounts, n_bind_mounts,
|
|
tmp_dir, var_tmp_dir,
|
|
protect_home, protect_system);
|
|
|
|
/* Set mount slave mode */
|
|
if (root || n_mounts > 0)
|
|
make_slave = true;
|
|
|
|
if (n_mounts > 0) {
|
|
m = mounts = (MountEntry *) alloca0(n_mounts * sizeof(MountEntry));
|
|
r = append_access_mounts(&m, read_write_paths, READWRITE, require_prefix);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
r = append_access_mounts(&m, read_only_paths, READONLY, require_prefix);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
r = append_access_mounts(&m, inaccessible_paths, INACCESSIBLE, require_prefix);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
r = append_empty_dir_mounts(&m, empty_directories);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
r = append_bind_mounts(&m, bind_mounts, n_bind_mounts);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
if (tmp_dir) {
|
|
*(m++) = (MountEntry) {
|
|
.path_const = "/tmp",
|
|
.mode = PRIVATE_TMP,
|
|
};
|
|
}
|
|
|
|
if (var_tmp_dir) {
|
|
*(m++) = (MountEntry) {
|
|
.path_const = "/var/tmp",
|
|
.mode = PRIVATE_VAR_TMP,
|
|
};
|
|
}
|
|
|
|
if (ns_info->private_dev) {
|
|
*(m++) = (MountEntry) {
|
|
.path_const = "/dev",
|
|
.mode = PRIVATE_DEV,
|
|
};
|
|
}
|
|
|
|
if (ns_info->protect_kernel_tunables) {
|
|
r = append_static_mounts(&m, protect_kernel_tunables_table, ELEMENTSOF(protect_kernel_tunables_table), ns_info->ignore_protect_paths);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
if (ns_info->protect_kernel_modules) {
|
|
r = append_static_mounts(&m, protect_kernel_modules_table, ELEMENTSOF(protect_kernel_modules_table), ns_info->ignore_protect_paths);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
if (ns_info->protect_control_groups) {
|
|
*(m++) = (MountEntry) {
|
|
.path_const = "/sys/fs/cgroup",
|
|
.mode = READONLY,
|
|
};
|
|
}
|
|
|
|
r = append_protect_home(&m, protect_home, ns_info->ignore_protect_paths);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
r = append_protect_system(&m, protect_system, false);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
if (namespace_info_mount_apivfs(root, ns_info)) {
|
|
r = append_static_mounts(&m, apivfs_table, ELEMENTSOF(apivfs_table), ns_info->ignore_protect_paths);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
assert(mounts + n_mounts == m);
|
|
|
|
/* Prepend the root directory where that's necessary */
|
|
r = prefix_where_needed(mounts, n_mounts, root);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
qsort(mounts, n_mounts, sizeof(MountEntry), mount_path_compare);
|
|
|
|
drop_duplicates(mounts, &n_mounts);
|
|
drop_outside_root(root, mounts, &n_mounts);
|
|
drop_inaccessible(mounts, &n_mounts);
|
|
drop_nop(mounts, &n_mounts);
|
|
}
|
|
|
|
if (unshare(CLONE_NEWNS) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
if (make_slave) {
|
|
/* Remount / as SLAVE so that nothing now mounted in the namespace
|
|
shows up in the parent */
|
|
if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
if (root_image) {
|
|
/* A root image is specified, mount it to the right place */
|
|
r = dissected_image_mount(dissected_image, root, UID_INVALID, dissect_image_flags);
|
|
if (r < 0)
|
|
goto finish;
|
|
|
|
if (decrypted_image) {
|
|
r = decrypted_image_relinquish(decrypted_image);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
loop_device_relinquish(loop_device);
|
|
|
|
} else if (root_directory) {
|
|
|
|
/* A root directory is specified. Turn its directory into bind mount, if it isn't one yet. */
|
|
r = path_is_mount_point(root, NULL, AT_SYMLINK_FOLLOW);
|
|
if (r < 0)
|
|
goto finish;
|
|
if (r == 0) {
|
|
if (mount(root, root, NULL, MS_BIND|MS_REC, NULL) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
} else if (root) {
|
|
|
|
/* Let's mount the main root directory to the root directory to use */
|
|
if (mount("/", root, NULL, MS_BIND|MS_REC, NULL) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
/* Try to set up the new root directory before mounting anything else there. */
|
|
if (root_image || root_directory)
|
|
(void) base_filesystem_create(root, UID_INVALID, GID_INVALID);
|
|
|
|
if (n_mounts > 0) {
|
|
_cleanup_fclose_ FILE *proc_self_mountinfo = NULL;
|
|
char **blacklist;
|
|
unsigned j;
|
|
|
|
/* Open /proc/self/mountinfo now as it may become unavailable if we mount anything on top of /proc.
|
|
* For example, this is the case with the option: 'InaccessiblePaths=/proc' */
|
|
proc_self_mountinfo = fopen("/proc/self/mountinfo", "re");
|
|
if (!proc_self_mountinfo) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
/* First round, add in all special mounts we need */
|
|
for (m = mounts; m < mounts + n_mounts; ++m) {
|
|
r = apply_mount(root, m, tmp_dir, var_tmp_dir);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
/* Create a blacklist we can pass to bind_mount_recursive() */
|
|
blacklist = newa(char*, n_mounts+1);
|
|
for (j = 0; j < n_mounts; j++)
|
|
blacklist[j] = (char*) mount_entry_path(mounts+j);
|
|
blacklist[j] = NULL;
|
|
|
|
/* Second round, flip the ro bits if necessary. */
|
|
for (m = mounts; m < mounts + n_mounts; ++m) {
|
|
r = make_read_only(m, blacklist, proc_self_mountinfo);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
}
|
|
|
|
if (root) {
|
|
/* MS_MOVE does not work on MS_SHARED so the remount MS_SHARED will be done later */
|
|
r = mount_move_root(root);
|
|
if (r < 0)
|
|
goto finish;
|
|
}
|
|
|
|
/* Remount / as the desired mode. Not that this will not
|
|
* reestablish propagation from our side to the host, since
|
|
* what's disconnected is disconnected. */
|
|
if (mount(NULL, "/", NULL, mount_flags | MS_REC, NULL) < 0) {
|
|
r = -errno;
|
|
goto finish;
|
|
}
|
|
|
|
r = 0;
|
|
|
|
finish:
|
|
for (m = mounts; m < mounts + n_mounts; m++)
|
|
mount_entry_done(m);
|
|
|
|
return r;
|
|
}
|
|
|
|
void bind_mount_free_many(BindMount *b, unsigned n) {
|
|
unsigned i;
|
|
|
|
assert(b || n == 0);
|
|
|
|
for (i = 0; i < n; i++) {
|
|
free(b[i].source);
|
|
free(b[i].destination);
|
|
}
|
|
|
|
free(b);
|
|
}
|
|
|
|
int bind_mount_add(BindMount **b, unsigned *n, const BindMount *item) {
|
|
_cleanup_free_ char *s = NULL, *d = NULL;
|
|
BindMount *c;
|
|
|
|
assert(b);
|
|
assert(n);
|
|
assert(item);
|
|
|
|
s = strdup(item->source);
|
|
if (!s)
|
|
return -ENOMEM;
|
|
|
|
d = strdup(item->destination);
|
|
if (!d)
|
|
return -ENOMEM;
|
|
|
|
c = realloc_multiply(*b, sizeof(BindMount), *n + 1);
|
|
if (!c)
|
|
return -ENOMEM;
|
|
|
|
*b = c;
|
|
|
|
c[(*n) ++] = (BindMount) {
|
|
.source = s,
|
|
.destination = d,
|
|
.read_only = item->read_only,
|
|
.recursive = item->recursive,
|
|
.ignore_enoent = item->ignore_enoent,
|
|
};
|
|
|
|
s = d = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static int setup_one_tmp_dir(const char *id, const char *prefix, char **path) {
|
|
_cleanup_free_ char *x = NULL;
|
|
char bid[SD_ID128_STRING_MAX];
|
|
sd_id128_t boot_id;
|
|
int r;
|
|
|
|
assert(id);
|
|
assert(prefix);
|
|
assert(path);
|
|
|
|
/* We include the boot id in the directory so that after a
|
|
* reboot we can easily identify obsolete directories. */
|
|
|
|
r = sd_id128_get_boot(&boot_id);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
x = strjoin(prefix, "/systemd-private-", sd_id128_to_string(boot_id, bid), "-", id, "-XXXXXX");
|
|
if (!x)
|
|
return -ENOMEM;
|
|
|
|
RUN_WITH_UMASK(0077)
|
|
if (!mkdtemp(x))
|
|
return -errno;
|
|
|
|
RUN_WITH_UMASK(0000) {
|
|
char *y;
|
|
|
|
y = strjoina(x, "/tmp");
|
|
|
|
if (mkdir(y, 0777 | S_ISVTX) < 0)
|
|
return -errno;
|
|
}
|
|
|
|
*path = x;
|
|
x = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int setup_tmp_dirs(const char *id, char **tmp_dir, char **var_tmp_dir) {
|
|
char *a, *b;
|
|
int r;
|
|
|
|
assert(id);
|
|
assert(tmp_dir);
|
|
assert(var_tmp_dir);
|
|
|
|
r = setup_one_tmp_dir(id, "/tmp", &a);
|
|
if (r < 0)
|
|
return r;
|
|
|
|
r = setup_one_tmp_dir(id, "/var/tmp", &b);
|
|
if (r < 0) {
|
|
char *t;
|
|
|
|
t = strjoina(a, "/tmp");
|
|
rmdir(t);
|
|
rmdir(a);
|
|
|
|
free(a);
|
|
return r;
|
|
}
|
|
|
|
*tmp_dir = a;
|
|
*var_tmp_dir = b;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int setup_netns(int netns_storage_socket[2]) {
|
|
_cleanup_close_ int netns = -1;
|
|
int r, q;
|
|
|
|
assert(netns_storage_socket);
|
|
assert(netns_storage_socket[0] >= 0);
|
|
assert(netns_storage_socket[1] >= 0);
|
|
|
|
/* We use the passed socketpair as a storage buffer for our
|
|
* namespace reference fd. Whatever process runs this first
|
|
* shall create a new namespace, all others should just join
|
|
* it. To serialize that we use a file lock on the socket
|
|
* pair.
|
|
*
|
|
* It's a bit crazy, but hey, works great! */
|
|
|
|
if (lockf(netns_storage_socket[0], F_LOCK, 0) < 0)
|
|
return -errno;
|
|
|
|
netns = receive_one_fd(netns_storage_socket[0], MSG_DONTWAIT);
|
|
if (netns == -EAGAIN) {
|
|
/* Nothing stored yet, so let's create a new namespace */
|
|
|
|
if (unshare(CLONE_NEWNET) < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
loopback_setup();
|
|
|
|
netns = open("/proc/self/ns/net", O_RDONLY|O_CLOEXEC|O_NOCTTY);
|
|
if (netns < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
r = 1;
|
|
|
|
} else if (netns < 0) {
|
|
r = netns;
|
|
goto fail;
|
|
|
|
} else {
|
|
/* Yay, found something, so let's join the namespace */
|
|
if (setns(netns, CLONE_NEWNET) < 0) {
|
|
r = -errno;
|
|
goto fail;
|
|
}
|
|
|
|
r = 0;
|
|
}
|
|
|
|
q = send_one_fd(netns_storage_socket[1], netns, MSG_DONTWAIT);
|
|
if (q < 0) {
|
|
r = q;
|
|
goto fail;
|
|
}
|
|
|
|
fail:
|
|
(void) lockf(netns_storage_socket[0], F_ULOCK, 0);
|
|
return r;
|
|
}
|
|
|
|
bool ns_type_supported(NamespaceType type) {
|
|
const char *t, *ns_proc;
|
|
|
|
t = namespace_type_to_string(type);
|
|
if (!t) /* Don't know how to translate this? Then it's not supported */
|
|
return false;
|
|
|
|
ns_proc = strjoina("/proc/self/ns/", t);
|
|
return access(ns_proc, F_OK) == 0;
|
|
}
|
|
|
|
static const char *const protect_home_table[_PROTECT_HOME_MAX] = {
|
|
[PROTECT_HOME_NO] = "no",
|
|
[PROTECT_HOME_YES] = "yes",
|
|
[PROTECT_HOME_READ_ONLY] = "read-only",
|
|
};
|
|
|
|
DEFINE_STRING_TABLE_LOOKUP(protect_home, ProtectHome);
|
|
|
|
ProtectHome parse_protect_home_or_bool(const char *s) {
|
|
int r;
|
|
|
|
r = parse_boolean(s);
|
|
if (r > 0)
|
|
return PROTECT_HOME_YES;
|
|
if (r == 0)
|
|
return PROTECT_HOME_NO;
|
|
|
|
return protect_home_from_string(s);
|
|
}
|
|
|
|
static const char *const protect_system_table[_PROTECT_SYSTEM_MAX] = {
|
|
[PROTECT_SYSTEM_NO] = "no",
|
|
[PROTECT_SYSTEM_YES] = "yes",
|
|
[PROTECT_SYSTEM_FULL] = "full",
|
|
[PROTECT_SYSTEM_STRICT] = "strict",
|
|
};
|
|
|
|
DEFINE_STRING_TABLE_LOOKUP(protect_system, ProtectSystem);
|
|
|
|
static const char* const namespace_type_table[] = {
|
|
[NAMESPACE_MOUNT] = "mnt",
|
|
[NAMESPACE_CGROUP] = "cgroup",
|
|
[NAMESPACE_UTS] = "uts",
|
|
[NAMESPACE_IPC] = "ipc",
|
|
[NAMESPACE_USER] = "user",
|
|
[NAMESPACE_PID] = "pid",
|
|
[NAMESPACE_NET] = "net",
|
|
};
|
|
|
|
DEFINE_STRING_TABLE_LOOKUP(namespace_type, NamespaceType);
|