--- /dev/null
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ 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/>.
+***/
+
+#include <sys/mount.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ftw.h>
+
+#include "mount-setup.h"
+//#include "dev-setup.h"
+//#include "bus-util.h"
+//#include "log.h"
+#include "macro.h"
+//#include "util.h"
+#include "label.h"
+//#include "set.h"
+//#include "strv.h"
+#include "mkdir.h"
+#include "path-util.h"
+//#include "missing.h"
+#include "virt.h"
+//#include "efivars.h"
+//#include "smack-util.h"
+#include "cgroup-util.h"
+
+typedef enum MountMode {
+ MNT_NONE = 0,
+ MNT_FATAL = 1 << 0,
+ MNT_IN_CONTAINER = 1 << 1,
+} MountMode;
+
+typedef struct MountPoint {
+ const char *what;
+ const char *where;
+ const char *type;
+ const char *options;
+ unsigned long flags;
+ bool (*condition_fn)(void);
+ MountMode mode;
+} MountPoint;
+
+/* The first three entries we might need before SELinux is up. The
+ * fourth (securityfs) is needed by IMA to load a custom policy. The
+ * other ones we can delay until SELinux and IMA are loaded. When
+ * SMACK is enabled we need smackfs, too, so it's a fifth one. */
+#ifdef HAVE_SMACK
+#define N_EARLY_MOUNT 5
+#else
+#define N_EARLY_MOUNT 4
+#endif
+
+static const MountPoint mount_table[] = {
+/// UNNEEDED by elogind
+#if 0
+ { "sysfs", "/sys", "sysfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ NULL, MNT_FATAL|MNT_IN_CONTAINER },
+ { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ NULL, MNT_FATAL|MNT_IN_CONTAINER },
+ { "devtmpfs", "/dev", "devtmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME,
+ NULL, MNT_FATAL|MNT_IN_CONTAINER },
+ { "securityfs", "/sys/kernel/security", "securityfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ NULL, MNT_NONE },
+#ifdef HAVE_SMACK
+ { "smackfs", "/sys/fs/smackfs", "smackfs", "smackfsdef=*", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ mac_smack_use, MNT_FATAL },
+ { "tmpfs", "/dev/shm", "tmpfs", "mode=1777,smackfsroot=*", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+ mac_smack_use, MNT_FATAL },
+#endif
+ { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+ NULL, MNT_FATAL|MNT_IN_CONTAINER },
+ { "devpts", "/dev/pts", "devpts", "mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC,
+ NULL, MNT_IN_CONTAINER },
+#ifdef HAVE_SMACK
+ { "tmpfs", "/run", "tmpfs", "mode=755,smackfsroot=*", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+ mac_smack_use, MNT_FATAL },
+#endif
+ { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+ NULL, MNT_FATAL|MNT_IN_CONTAINER },
+ { "cgroup", "/sys/fs/cgroup", "cgroup", "__DEVEL__sane_behavior", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ cg_is_unified_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+#endif // 0
+ { "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME,
+ cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+/// UNNEEDED by elogind
+#if 0
+ { "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd,xattr", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ cg_is_legacy_wanted, MNT_IN_CONTAINER },
+ { "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+#else
+ { "cgroup", "/sys/fs/cgroup/elogind", "cgroup", "none,name=elogind,xattr", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ cg_is_legacy_wanted, MNT_IN_CONTAINER },
+ { "cgroup", "/sys/fs/cgroup/elogind", "cgroup", "none,name=elogind", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
+#endif // 0
+/// UNNEEDED by elogind
+#if 0
+ { "pstore", "/sys/fs/pstore", "pstore", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ NULL, MNT_NONE },
+#ifdef ENABLE_EFI
+ { "efivarfs", "/sys/firmware/efi/efivars", "efivarfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ is_efi_boot, MNT_NONE },
+#endif
+ { "kdbusfs", "/sys/fs/kdbus", "kdbusfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ is_kdbus_wanted, MNT_IN_CONTAINER },
+#endif // 0
+};
+
+/// UNNEEDED by elogind
+#if 0
+/* These are API file systems that might be mounted by other software,
+ * we just list them here so that we know that we should ignore them */
+
+static const char ignore_paths[] =
+ /* SELinux file systems */
+ "/sys/fs/selinux\0"
+ /* Container bind mounts */
+ "/proc/sys\0"
+ "/dev/console\0"
+ "/proc/kmsg\0";
+
+bool mount_point_is_api(const char *path) {
+ unsigned i;
+
+ /* Checks if this mount point is considered "API", and hence
+ * should be ignored */
+
+ for (i = 0; i < ELEMENTSOF(mount_table); i ++)
+ if (path_equal(path, mount_table[i].where))
+ return true;
+
+ return path_startswith(path, "/sys/fs/cgroup/");
+}
+
+bool mount_point_ignore(const char *path) {
+ const char *i;
+
+ NULSTR_FOREACH(i, ignore_paths)
+ if (path_equal(path, i))
+ return true;
+
+ return false;
+}
+#endif // 0
+
+static int mount_one(const MountPoint *p, bool relabel) {
+ int r;
+
+ assert(p);
+
+ if (p->condition_fn && !p->condition_fn())
+ return 0;
+
+ /* Relabel first, just in case */
+ if (relabel)
+ label_fix(p->where, true, true);
+
+ r = path_is_mount_point(p->where, AT_SYMLINK_FOLLOW);
+ if (r < 0 && r != -ENOENT)
+ return r;
+ if (r > 0)
+ return 0;
+
+ /* Skip securityfs in a container */
+ if (!(p->mode & MNT_IN_CONTAINER) && detect_container(NULL) > 0)
+ return 0;
+
+ /* The access mode here doesn't really matter too much, since
+ * the mounted file system will take precedence anyway. */
+ if (relabel)
+ mkdir_p_label(p->where, 0755);
+ else
+ mkdir_p(p->where, 0755);
+
+ log_debug("Mounting %s to %s of type %s with options %s.",
+ p->what,
+ p->where,
+ p->type,
+ strna(p->options));
+
+ if (mount(p->what,
+ p->where,
+ p->type,
+ p->flags,
+ p->options) < 0) {
+ log_full((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, "Failed to mount %s at %s: %m", p->type, p->where);
+ return (p->mode & MNT_FATAL) ? -errno : 0;
+ }
+
+ /* Relabel again, since we now mounted something fresh here */
+ if (relabel)
+ label_fix(p->where, false, false);
+
+ return 1;
+}
+
+/// UNNEEDED by elogind
+#if 0
+int mount_setup_early(void) {
+ unsigned i;
+ int r = 0;
+
+ assert_cc(N_EARLY_MOUNT <= ELEMENTSOF(mount_table));
+
+ /* Do a minimal mount of /proc and friends to enable the most
+ * basic stuff, such as SELinux */
+ for (i = 0; i < N_EARLY_MOUNT; i ++) {
+ int j;
+
+ j = mount_one(mount_table + i, false);
+ if (r == 0)
+ r = j;
+ }
+
+ return r;
+}
+
+int mount_cgroup_controllers(char ***join_controllers) {
+ _cleanup_set_free_free_ Set *controllers = NULL;
+ int r;
+
+ if (!cg_is_legacy_wanted())
+ return 0;
+
+ /* Mount all available cgroup controllers that are built into the kernel. */
+
+ 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 enumerate cgroup controllers: %m");
+
+ for (;;) {
+ _cleanup_free_ char *options = NULL, *controller = NULL, *where = NULL;
+ MountPoint p = {
+ .what = "cgroup",
+ .type = "cgroup",
+ .flags = MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ .mode = MNT_IN_CONTAINER,
+ };
+ char ***k = NULL;
+
+ controller = set_steal_first(controllers);
+ if (!controller)
+ break;
+
+ if (join_controllers)
+ for (k = join_controllers; *k; k++)
+ if (strv_find(*k, controller))
+ break;
+
+ if (k && *k) {
+ char **i, **j;
+
+ for (i = *k, j = *k; *i; i++) {
+
+ if (!streq(*i, controller)) {
+ _cleanup_free_ char *t;
+
+ t = set_remove(controllers, *i);
+ if (!t) {
+ free(*i);
+ continue;
+ }
+ }
+
+ *(j++) = *i;
+ }
+
+ *j = NULL;
+
+ options = strv_join(*k, ",");
+ if (!options)
+ return log_oom();
+ } else {
+ options = controller;
+ controller = NULL;
+ }
+
+ where = strappend("/sys/fs/cgroup/", options);
+ if (!where)
+ return log_oom();
+
+ p.where = where;
+ p.options = options;
+
+ r = mount_one(&p, true);
+ if (r < 0)
+ return r;
+
+ if (r > 0 && k && *k) {
+ char **i;
+
+ for (i = *k; *i; i++) {
+ _cleanup_free_ char *t = NULL;
+
+ t = strappend("/sys/fs/cgroup/", *i);
+ if (!t)
+ return log_oom();
+
+ r = symlink(options, t);
+ if (r < 0 && errno != EEXIST)
+ return log_error_errno(errno, "Failed to create symlink %s: %m", t);
+ }
+ }
+ }
+
+ /* Now that we mounted everything, let's make the tmpfs the
+ * cgroup file systems are mounted into read-only. */
+ (void) mount("tmpfs", "/sys/fs/cgroup", "tmpfs", MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME|MS_RDONLY, "mode=755");
+
+ return 0;
+}
+
+#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
+static int nftw_cb(
+ const char *fpath,
+ const struct stat *sb,
+ int tflag,
+ struct FTW *ftwbuf) {
+
+ /* No need to label /dev twice in a row... */
+ if (_unlikely_(ftwbuf->level == 0))
+ return FTW_CONTINUE;
+
+ label_fix(fpath, false, false);
+
+ /* /run/initramfs is static data and big, no need to
+ * dynamically relabel its contents at boot... */
+ if (_unlikely_(ftwbuf->level == 1 &&
+ tflag == FTW_D &&
+ streq(fpath, "/run/initramfs")))
+ return FTW_SKIP_SUBTREE;
+
+ return FTW_CONTINUE;
+};
+#endif
+#endif // 0
+
+int mount_setup(bool loaded_policy) {
+ unsigned i;
+ int r = 0;
+
+ for (i = 0; i < ELEMENTSOF(mount_table); i ++) {
+ int j;
+
+ j = mount_one(mount_table + i, loaded_policy);
+ if (r == 0)
+ r = j;
+ }
+
+ if (r < 0)
+ return r;
+
+/// elogind does not control /, /dev, /run and /run/systemd/* are setup elsewhere.
+#if 0
+#if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
+ /* Nodes in devtmpfs and /run need to be manually updated for
+ * the appropriate labels, after mounting. The other virtual
+ * API file systems like /sys and /proc do not need that, they
+ * use the same label for all their files. */
+ if (loaded_policy) {
+ usec_t before_relabel, after_relabel;
+ char timespan[FORMAT_TIMESPAN_MAX];
+
+ before_relabel = now(CLOCK_MONOTONIC);
+
+ nftw("/dev", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+ nftw("/run", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+
+ after_relabel = now(CLOCK_MONOTONIC);
+
+ log_info("Relabelled /dev and /run in %s.",
+ format_timespan(timespan, sizeof(timespan), after_relabel - before_relabel, 0));
+ }
+#endif
+
+ /* Create a few default symlinks, which are normally created
+ * by udevd, but some scripts might need them before we start
+ * udevd. */
+ dev_setup(NULL, UID_INVALID, GID_INVALID);
+
+ /* Mark the root directory as shared in regards to mount
+ * propagation. The kernel defaults to "private", but we think
+ * it makes more sense to have a default of "shared" so that
+ * nspawn and the container tools work out of the box. If
+ * specific setups need other settings they can reset the
+ * propagation mode to private if needed. */
+ if (detect_container(NULL) <= 0)
+ if (mount(NULL, "/", NULL, MS_REC|MS_SHARED, NULL) < 0)
+ log_warning_errno(errno, "Failed to set up the root directory for shared mount propagation: %m");
+
+ /* Create a few directories we always want around, Note that
+ * sd_booted() checks for /run/systemd/system, so this mkdir
+ * really needs to stay for good, otherwise software that
+ * copied sd-daemon.c into their sources will misdetect
+ * systemd. */
+ mkdir_label("/run/systemd", 0755);
+ mkdir_label("/run/systemd/system", 0755);
+ mkdir_label("/run/systemd/inaccessible", 0000);
+#endif // 0
+
+ return 0;
+}
~ianmdlvl / elogind.git / commitdiff