initd/early.c

   1 /*
   2  * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   3  * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU Lesser General Public License version 2.1
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/mount.h>
  16 #include <sys/types.h>
  17 #include <sys/stat.h>
  18 #include <sys/sysmacros.h>
  19
  20 #include <stdio.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24
  25 #include "../utils/utils.h"
  26 #include "init.h"
  27 #include "../libc-compat.h"
  28 #include "../container.h"
  29
  30 static void
  31 early_dev(void)
  32 {
  33         mkdev("*", 0600);
  34         mknod("/dev/null", 0666, makedev(1, 3));
  35 }
  36
  37 static void
  38 early_console(const char *dev)
  39 {
  40         struct stat s;
  41
  42         if (stat(dev, &s)) {
  43                 ERROR("Failed to stat %s: %m\n", dev);
  44                 return;
  45         }
  46
  47         if (patch_stdio(dev)) {
  48                 ERROR("Failed to setup i/o redirection\n");
  49                 return;
  50         }
  51
  52         fcntl(STDERR_FILENO, F_SETFL, fcntl(STDERR_FILENO, F_GETFL) | O_NONBLOCK);
  53 }
  54
  55 static void
  56 early_mounts(void)
  57 {
  58         unsigned int oldumask = umask(0);
  59
  60         if (!is_container()) {
  61                 mount("proc", "/proc", "proc", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  62                 mount("sysfs", "/sys", "sysfs", MS_NOATIME | MS_NODEV | MS_NOEXEC | MS_NOSUID, 0);
  63                 mount("cgroup2", "/sys/fs/cgroup", "cgroup2",  MS_NODEV | MS_NOEXEC | MS_NOSUID | MS_RELATIME, "nsdelegate");
  64                 mount("tmpfs", "/dev", "tmpfs", MS_NOATIME | MS_NOSUID, "mode=0755,size=512K");
  65                 ignore(symlink("/tmp/shm", "/dev/shm"));
  66                 mkdir("/dev/pts", 0755);
  67                 mount("devpts", "/dev/pts", "devpts", MS_NOATIME | MS_NOEXEC | MS_NOSUID, "mode=600");
  68
  69                 early_dev();
  70         }
  71
  72         early_console("/dev/console");
  73         if (mount_zram_on_tmp()) {
  74                 mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME, "mode=01777");
  75                 mkdir("/tmp/shm", 01777);
  76         } else {
  77                 mkdir("/tmp/shm", 01777);
  78                 mount("tmpfs", "/tmp/shm", "tmpfs", MS_NOSUID | MS_NODEV | MS_NOATIME,
  79                                 "mode=01777");
  80         }
  81         mkdir("/tmp/run", 0755);
  82         mkdir("/tmp/lock", 0755);
  83         mkdir("/tmp/state", 0755);
  84         umask(oldumask);
  85 }
  86
  87 static void
  88 early_env(void)
  89 {
  90         setenv("PATH", EARLY_PATH, 1);
  91 }
  92
  93 void
  94 early(void)
  95 {
  96         if (getpid() != 1)
  97                 return;
  98
  99         early_mounts();
 100         early_env();
 101
 102         LOG("Console is alive\n");
 103 }