2002-06-23 04:24:25 +00:00
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/* vi: set sw=4 ts=4: */
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2006-07-12 07:56:04 +00:00
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/*
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2006-09-08 17:22:05 +00:00
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* Mini sulogin implementation for busybox
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*
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2010-08-16 18:14:46 +00:00
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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2006-07-12 07:56:04 +00:00
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*/
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2015-10-18 23:20:36 +00:00
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//config:config SULOGIN
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//config: bool "sulogin"
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//config: default y
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//config: select FEATURE_SYSLOG
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//config: help
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//config: sulogin is invoked when the system goes into single user
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//config: mode (this is done through an entry in inittab).
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//applet:IF_SULOGIN(APPLET(sulogin, BB_DIR_SBIN, BB_SUID_DROP))
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//kbuild:lib-$(CONFIG_SULOGIN) += sulogin.o
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2006-07-12 07:56:04 +00:00
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2011-04-01 20:56:30 +00:00
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//usage:#define sulogin_trivial_usage
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//usage: "[-t N] [TTY]"
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//usage:#define sulogin_full_usage "\n\n"
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//usage: "Single user login\n"
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//usage: "\n -t N Timeout"
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2007-05-26 19:00:18 +00:00
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#include "libbb.h"
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2008-01-27 12:50:12 +00:00
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#include <syslog.h>
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2002-06-23 04:24:25 +00:00
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2007-10-11 10:05:36 +00:00
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int sulogin_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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2008-07-05 09:18:54 +00:00
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int sulogin_main(int argc UNUSED_PARAM, char **argv)
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2002-06-23 04:24:25 +00:00
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{
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int timeout = 0;
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2006-09-08 17:22:05 +00:00
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struct passwd *pwd;
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2006-10-14 11:47:02 +00:00
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const char *shell;
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2006-01-25 00:08:53 +00:00
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2016-03-30 15:27:32 +00:00
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/* Note: sulogin is not a suid app. It is meant to be run by init
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* for single user / emergency mode. init starts it as root.
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* Normal users (potentially malisious ones) can only run it under
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* their UID, therefore no paranoia here is warranted:
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* $LD_LIBRARY_PATH in env, TTY = /dev/sda
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* are no more dangerous here than in e.g. cp applet.
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*/
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2006-09-09 14:00:58 +00:00
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logmode = LOGMODE_BOTH;
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2006-10-03 21:00:43 +00:00
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openlog(applet_name, 0, LOG_AUTH);
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2006-01-25 00:08:53 +00:00
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2016-07-06 19:58:02 +00:00
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getopt32(argv, "t:+", &timeout);
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2008-11-09 00:15:11 +00:00
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argv += optind;
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2006-09-08 17:22:05 +00:00
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2008-11-09 00:15:11 +00:00
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if (argv[0]) {
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2006-09-08 17:22:05 +00:00
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close(0);
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close(1);
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2008-11-09 00:15:11 +00:00
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dup(xopen(argv[0], O_RDWR));
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2006-09-11 00:34:01 +00:00
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close(2);
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2006-09-08 17:22:05 +00:00
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dup(0);
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2002-06-23 04:24:25 +00:00
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}
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2006-09-08 17:22:05 +00:00
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2006-10-14 11:47:02 +00:00
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pwd = getpwuid(0);
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if (!pwd) {
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2016-03-30 15:27:32 +00:00
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bb_error_msg_and_die("no password entry for root");
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2006-09-17 16:28:10 +00:00
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}
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2006-09-08 17:22:05 +00:00
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2002-06-23 04:24:25 +00:00
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while (1) {
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2008-06-12 16:56:52 +00:00
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int r;
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2013-11-19 12:09:06 +00:00
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r = ask_and_check_password_extended(pwd, timeout,
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"Give root password for system maintenance\n"
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"(or type Control-D for normal startup):"
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);
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if (r < 0) {
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2013-05-21 15:01:55 +00:00
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/* ^D, ^C, timeout, or read error */
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2016-03-30 15:36:20 +00:00
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bb_error_msg("normal startup");
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2006-09-09 14:00:58 +00:00
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return 0;
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2002-06-23 04:24:25 +00:00
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}
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2013-11-19 12:09:06 +00:00
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if (r > 0) {
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2002-06-23 04:24:25 +00:00
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break;
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}
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2011-03-08 20:07:05 +00:00
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bb_do_delay(LOGIN_FAIL_DELAY);
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2016-03-30 15:36:20 +00:00
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bb_error_msg("Login incorrect");
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2002-06-23 04:24:25 +00:00
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}
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2005-05-03 06:25:50 +00:00
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2016-03-30 15:36:20 +00:00
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bb_error_msg("starting shell for system maintenance");
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2005-05-03 06:25:50 +00:00
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2009-04-21 11:09:40 +00:00
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IF_SELINUX(renew_current_security_context());
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2005-05-03 06:25:50 +00:00
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2006-10-14 11:47:02 +00:00
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shell = getenv("SUSHELL");
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2007-09-10 13:15:28 +00:00
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if (!shell)
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shell = getenv("sushell");
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2010-06-27 01:23:31 +00:00
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if (!shell)
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shell = pwd->pw_shell;
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2007-09-10 13:15:28 +00:00
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/* Exec login shell with no additional parameters. Never returns. */
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2016-11-03 21:13:08 +00:00
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run_shell(shell, 1, NULL);
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2002-06-23 04:24:25 +00:00
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}
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