1/*** 2 This file is part of systemd. 3 4 Copyright 2003-2004 Greg Kroah-Hartman <greg@kroah.com> 5 Copyright 2004-2012 Kay Sievers <kay@vrfy.org> 6 7 systemd is free software; you can redistribute it and/or modify it 8 under the terms of the GNU Lesser General Public License as published by 9 the Free Software Foundation; either version 2.1 of the License, or 10 (at your option) any later version. 11 12 systemd is distributed in the hope that it will be useful, but 13 WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 Lesser General Public License for more details. 16 17 You should have received a copy of the GNU Lesser General Public License 18 along with systemd; If not, see <http://www.gnu.org/licenses/>. 19***/ 20 21#include <stdio.h> 22#include <stddef.h> 23#include <stdlib.h> 24#include <string.h> 25#include <fcntl.h> 26#include <ctype.h> 27#include <errno.h> 28#include <unistd.h> 29#include <grp.h> 30#include <sched.h> 31#include <sys/mount.h> 32#include <sys/signalfd.h> 33 34#include "missing.h" 35#include "udev.h" 36#include "udev-util.h" 37 38#ifndef HAVE_UNSHARE 39#include <sys/syscall.h> 40/* Provide our own replacement with local reach*/ 41static inline int unshare (int x) { return syscall(SYS_unshare, x); } 42#endif 43 44#ifndef _USE_GNU 45/* Make sure CLONE_NEWNS macro is available */ 46#include <linux/sched.h> 47#endif 48 49static int fake_filesystems(void) { 50 static const struct fakefs { 51 const char *src; 52 const char *target; 53 const char *error; 54 } fakefss[] = { 55 { "test/sys", "/sys", "failed to mount test /sys" }, 56 { "test/dev", "/dev", "failed to mount test /dev" }, 57 { "test/run", UDEV_ROOT_RUN, "failed to mount test " UDEV_ROOT_RUN }, 58 { "test/run", "/etc/udev/rules.d", "failed to mount empty /etc/udev/rules.d" }, 59 { "test/run", "/lib/udev/rules.d", "failed to mount empty /lib/udev/rules.d" }, 60 }; 61 unsigned int i; 62 int err; 63 64 err = unshare(CLONE_NEWNS); 65 if (err < 0) { 66 err = -errno; 67 fprintf(stderr, "failed to call unshare(): %m\n"); 68 goto out; 69 } 70 71 if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) < 0) { 72 err = -errno; 73 fprintf(stderr, "failed to mount / as private: %m\n"); 74 goto out; 75 } 76 77 for (i = 0; i < ELEMENTSOF(fakefss); i++) { 78 err = mount(fakefss[i].src, fakefss[i].target, NULL, MS_BIND, NULL); 79 if (err < 0) { 80 err = -errno; 81 fprintf(stderr, "%s %m", fakefss[i].error); 82 return err; 83 } 84 } 85out: 86 return err; 87} 88 89int main(int argc, char *argv[]) { 90 _cleanup_udev_unref_ struct udev *udev = NULL; 91 _cleanup_udev_event_unref_ struct udev_event *event = NULL; 92 _cleanup_udev_device_unref_ struct udev_device *dev = NULL; 93 _cleanup_udev_rules_unref_ struct udev_rules *rules = NULL; 94 char syspath[UTIL_PATH_SIZE]; 95 const char *devpath; 96 const char *action; 97 sigset_t mask, sigmask_orig; 98 int err; 99 100 err = fake_filesystems(); 101 if (err < 0) 102 return EXIT_FAILURE; 103 104 udev = udev_new(); 105 if (udev == NULL) 106 return EXIT_FAILURE; 107 108 log_debug("version %s", VERSION); 109 mac_selinux_init("/dev"); 110 111 sigprocmask(SIG_SETMASK, NULL, &sigmask_orig); 112 113 action = argv[1]; 114 if (action == NULL) { 115 log_error("action missing"); 116 goto out; 117 } 118 119 devpath = argv[2]; 120 if (devpath == NULL) { 121 log_error("devpath missing"); 122 goto out; 123 } 124 125 rules = udev_rules_new(udev, 1); 126 127 strscpyl(syspath, sizeof(syspath), "/sys", devpath, NULL); 128 dev = udev_device_new_from_synthetic_event(udev, syspath, action); 129 if (dev == NULL) { 130 log_debug("unknown device '%s'", devpath); 131 goto out; 132 } 133 134 event = udev_event_new(dev); 135 136 sigfillset(&mask); 137 sigprocmask(SIG_SETMASK, &mask, &sigmask_orig); 138 event->fd_signal = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC); 139 if (event->fd_signal < 0) { 140 fprintf(stderr, "error creating signalfd\n"); 141 goto out; 142 } 143 144 /* do what devtmpfs usually provides us */ 145 if (udev_device_get_devnode(dev) != NULL) { 146 mode_t mode = 0600; 147 148 if (streq(udev_device_get_subsystem(dev), "block")) 149 mode |= S_IFBLK; 150 else 151 mode |= S_IFCHR; 152 153 if (!streq(action, "remove")) { 154 mkdir_parents_label(udev_device_get_devnode(dev), 0755); 155 mknod(udev_device_get_devnode(dev), mode, udev_device_get_devnum(dev)); 156 } else { 157 unlink(udev_device_get_devnode(dev)); 158 rmdir_parents(udev_device_get_devnode(dev), "/"); 159 } 160 } 161 162 udev_event_execute_rules(event, 163 3 * USEC_PER_SEC, USEC_PER_SEC, 164 NULL, 165 rules, 166 &sigmask_orig); 167 udev_event_execute_run(event, 168 3 * USEC_PER_SEC, USEC_PER_SEC, 169 NULL); 170out: 171 if (event != NULL && event->fd_signal >= 0) 172 close(event->fd_signal); 173 mac_selinux_finish(); 174 175 return err ? EXIT_FAILURE : EXIT_SUCCESS; 176} 177