diff options
Diffstat (limited to 'src/core/mount-setup.c')
| -rw-r--r-- | src/core/mount-setup.c | 419 |
1 files changed, 0 insertions, 419 deletions
diff --git a/src/core/mount-setup.c b/src/core/mount-setup.c deleted file mode 100644 index 5d8ab0ec70..0000000000 --- a/src/core/mount-setup.c +++ /dev/null @@ -1,419 +0,0 @@ -/*** - 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 <errno.h> -#include <ftw.h> -#include <stdlib.h> -#include <sys/mount.h> -#include <unistd.h> - -#include "alloc-util.h" -#include "bus-util.h" -#include "cgroup-util.h" -#include "dev-setup.h" -#include "efivars.h" -#include "fs-util.h" -#include "label.h" -#include "log.h" -#include "macro.h" -#include "missing.h" -#include "mkdir.h" -#include "mount-setup.h" -#include "mount-util.h" -#include "path-util.h" -#include "set.h" -#include "smack-util.h" -#include "strv.h" -#include "user-util.h" -#include "util.h" -#include "virt.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[] = { - { "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", "cgroup2", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, - cg_is_unified_wanted, MNT_FATAL|MNT_IN_CONTAINER }, - { "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, - cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER }, - { "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 }, - { "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 -}; - -/* 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; -} - -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) - (void) label_fix(p->where, true, true); - - r = path_is_mount_point(p->where, AT_SYMLINK_FOLLOW); - if (r < 0 && r != -ENOENT) { - log_full_errno((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, r, "Failed to determine whether %s is a mount point: %m", p->where); - return (p->mode & MNT_FATAL) ? r : 0; - } - if (r > 0) - return 0; - - /* Skip securityfs in a container */ - if (!(p->mode & MNT_IN_CONTAINER) && detect_container() > 0) - return 0; - - /* The access mode here doesn't really matter too much, since - * the mounted file system will take precedence anyway. */ - if (relabel) - (void) mkdir_p_label(p->where, 0755); - else - (void) 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_errno((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, errno, "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) - (void) label_fix(p->where, false, false); - - return 1; -} - -static int mount_points_setup(unsigned n, bool loaded_policy) { - unsigned i; - int r = 0; - - for (i = 0; i < n; i ++) { - int j; - - j = mount_one(mount_table + i, loaded_policy); - if (j != 0 && r >= 0) - r = j; - } - - return r; -} - -int mount_setup_early(void) { - 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 */ - return mount_points_setup(N_EARLY_MOUNT, false); -} - -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) { -#ifdef SMACK_RUN_LABEL - _cleanup_free_ char *src; - src = strappend("/sys/fs/cgroup/", options); - if (!src) - return log_oom(); - r = mac_smack_copy(t, src); - if (r < 0 && r != -EOPNOTSUPP) - return log_error_errno(r, "Failed to copy smack label from %s to %s: %m", src, t); -#endif - } else if (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 - -int mount_setup(bool loaded_policy) { - int r = 0; - - r = mount_points_setup(ELEMENTSOF(mount_table), loaded_policy); - - if (r < 0) - return r; - -#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("/dev/shm", 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() <= 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. */ - (void) mkdir_label("/run/systemd", 0755); - (void) mkdir_label("/run/systemd/system", 0755); - (void) mkdir_label("/run/systemd/inaccessible", 0000); - /* Set up inaccessible items */ - (void) mknod("/run/systemd/inaccessible/reg", S_IFREG | 0000, 0); - (void) mkdir_label("/run/systemd/inaccessible/dir", 0000); - (void) mknod("/run/systemd/inaccessible/chr", S_IFCHR | 0000, makedev(0, 0)); - (void) mknod("/run/systemd/inaccessible/blk", S_IFBLK | 0000, makedev(0, 0)); - (void) mkfifo("/run/systemd/inaccessible/fifo", 0000); - (void) mknod("/run/systemd/inaccessible/sock", S_IFSOCK | 0000, 0); - - return 0; -} |