+++ /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 <sys/stat.h>
-#include <stdlib.h>
-#include <string.h>
-#include <libgen.h>
-#include <assert.h>
-#include <unistd.h>
-#include <ftw.h>
-
-#include "mount-setup.h"
-#include "log.h"
-#include "macro.h"
-#include "util.h"
-#include "label.h"
-#include "set.h"
-#include "strv.h"
-#include "mkdir.h"
-
-#ifndef TTY_GID
-#define TTY_GID 5
-#endif
-
-typedef struct MountPoint {
- const char *what;
- const char *where;
- const char *type;
- const char *options;
- unsigned long flags;
- bool fatal;
-} 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. */
-#define N_EARLY_MOUNT 4
-
-static const MountPoint mount_table[] = {
- { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
- { "sysfs", "/sys", "sysfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
- { "devtmpfs", "/dev", "devtmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true },
- { "securityfs", "/sys/kernel/security", "securityfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, false },
- { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
- { "devpts", "/dev/pts", "devpts", "mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, false },
- { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
- { "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, false },
- { "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd", MS_NOSUID|MS_NOEXEC|MS_NODEV, false },
-};
-
-/* 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 * const ignore_paths[] = {
- "/sys/fs/selinux",
- "/selinux",
- "/proc/bus/usb"
-};
-
-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) {
- unsigned i;
-
- for (i = 0; i < ELEMENTSOF(ignore_paths); i++)
- if (path_equal(path, ignore_paths[i]))
- return true;
-
- return false;
-}
-
-static int mount_one(const MountPoint *p, bool relabel) {
- int r;
-
- assert(p);
-
- /* Relabel first, just in case */
- if (relabel)
- label_fix(p->where, true);
-
- if ((r = path_is_mount_point(p->where, true)) < 0)
- return r;
-
- if (r > 0)
- return 0;
-
- /* The access mode here doesn't really matter too much, since
- * the mounted file system will take precedence anyway. */
- 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_error("Failed to mount %s: %s", p->where, strerror(errno));
- return p->fatal ? -errno : 0;
- }
-
- /* Relabel again, since we now mounted something fresh here */
- if (relabel)
- label_fix(p->where, false);
-
- return 1;
-}
-
-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) {
- int r;
- FILE *f;
- char buf[LINE_MAX];
- Set *controllers;
-
- /* Mount all available cgroup controllers that are built into the kernel. */
-
- f = fopen("/proc/cgroups", "re");
- if (!f) {
- log_error("Failed to enumerate cgroup controllers: %m");
- return 0;
- }
-
- controllers = set_new(string_hash_func, string_compare_func);
- if (!controllers) {
- r = -ENOMEM;
- log_error("Failed to allocate controller set.");
- goto finish;
- }
-
- /* Ignore the header line */
- (void) fgets(buf, sizeof(buf), f);
-
- for (;;) {
- char *controller;
- int enabled = 0;
-
- if (fscanf(f, "%ms %*i %*i %i", &controller, &enabled) != 2) {
-
- if (feof(f))
- break;
-
- log_error("Failed to parse /proc/cgroups.");
- r = -EIO;
- goto finish;
- }
-
- if (!enabled) {
- free(controller);
- continue;
- }
-
- r = set_put(controllers, controller);
- if (r < 0) {
- log_error("Failed to add controller to set.");
- free(controller);
- goto finish;
- }
- }
-
- for (;;) {
- MountPoint p;
- char *controller, *where, *options;
- 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)) {
- char *t;
-
- t = set_remove(controllers, *i);
- if (!t) {
- free(*i);
- continue;
- }
- free(t);
- }
-
- *(j++) = *i;
- }
-
- *j = NULL;
-
- options = strv_join(*k, ",");
- if (!options) {
- log_error("Failed to join options");
- free(controller);
- r = -ENOMEM;
- goto finish;
- }
-
- } else {
- options = controller;
- controller = NULL;
- }
-
- where = strappend("/sys/fs/cgroup/", options);
- if (!where) {
- log_error("Failed to build path");
- free(options);
- r = -ENOMEM;
- goto finish;
- }
-
- zero(p);
- p.what = "cgroup";
- p.where = where;
- p.type = "cgroup";
- p.options = options;
- p.flags = MS_NOSUID|MS_NOEXEC|MS_NODEV;
- p.fatal = false;
-
- r = mount_one(&p, true);
- free(controller);
- free(where);
-
- if (r < 0) {
- free(options);
- goto finish;
- }
-
- if (r > 0 && k && *k) {
- char **i;
-
- for (i = *k; *i; i++) {
- char *t;
-
- t = strappend("/sys/fs/cgroup/", *i);
- if (!t) {
- log_error("Failed to build path");
- r = -ENOMEM;
- free(options);
- goto finish;
- }
-
- r = symlink(options, t);
- free(t);
-
- if (r < 0 && errno != EEXIST) {
- log_error("Failed to create symlink: %m");
- r = -errno;
- free(options);
- goto finish;
- }
- }
- }
-
- free(options);
- }
-
- r = 0;
-
-finish:
- set_free_free(controllers);
-
- fclose(f);
-
- return r;
-}
-
-static int symlink_and_label(const char *old_path, const char *new_path) {
- int r;
-
- assert(old_path);
- assert(new_path);
-
- if ((r = label_symlinkfile_set(new_path)) < 0)
- return r;
-
- if (symlink(old_path, new_path) < 0)
- r = -errno;
-
- label_file_clear();
-
- return r;
-}
-
-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, true);
-
- /* /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;
-};
-
-int mount_setup(bool loaded_policy) {
-
- static const char symlinks[] =
- "/proc/kcore\0" "/dev/core\0"
- "/proc/self/fd\0" "/dev/fd\0"
- "/proc/self/fd/0\0" "/dev/stdin\0"
- "/proc/self/fd/1\0" "/dev/stdout\0"
- "/proc/self/fd/2\0" "/dev/stderr\0";
-
- static const char relabel[] =
- "/run/initramfs/root-fsck\0"
- "/run/initramfs/shutdown\0";
-
- int r;
- unsigned i;
- const char *j, *k;
-
- for (i = 0; i < ELEMENTSOF(mount_table); i ++) {
- r = mount_one(mount_table + i, true);
-
- if (r < 0)
- return r;
- }
-
- /* 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);
-
- /* Explicitly relabel these */
- NULSTR_FOREACH(j, relabel)
- label_fix(j, true);
-
- after_relabel = now(CLOCK_MONOTONIC);
-
- log_info("Relabelled /dev and /run in %s.",
- format_timespan(timespan, sizeof(timespan), after_relabel - before_relabel));
- }
-
- /* Create a few default symlinks, which are normally created
- * by udevd, but some scripts might need them before we start
- * udevd. */
- NULSTR_FOREACH_PAIR(j, k, symlinks)
- symlink_and_label(j, k);
-
- /* Create a few directories we always want around */
- label_mkdir("/run/systemd", 0755);
- label_mkdir("/run/systemd/system", 0755);
-
- return 0;
-}
~ianmdlvl / elogind.git / blobdiff