/* vi: set sw=4 ts=4: */
+/*
+ * Mini su implementation for busybox
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
-#include <fcntl.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
+#include "libbb.h"
#include <syslog.h>
-#include <termios.h>
-#include <unistd.h>
-#include <utmp.h>
-#include <sys/resource.h>
-#include <sys/stat.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <ctype.h>
-#include <time.h>
-#include "busybox.h"
+#define SU_OPT_mp (3)
+#define SU_OPT_l (4)
-
-
-/* The shell to run if none is given in the user's passwd entry. */
-#define DEFAULT_USER "root"
-
-//#define SYSLOG_SUCCESS
-#define SYSLOG_FAILURE
-
-
-#if defined( SYSLOG_SUCCESS ) || defined( SYSLOG_FAILURE )
-/* Log the fact that someone has run su */
-
-# if defined( SYSLOG_SUCCESS ) && defined( SYSLOG_FAILURE )
-static void log_su (const char *successful, const char *old_user, const char *tty)
+int su_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int su_main(int argc UNUSED_PARAM, char **argv)
{
- syslog ( LOG_NOTICE, "%s%s on %s", successful, old_user, tty);
-}
-# define log_su_successful(cu, u, tty) if(!cu) log_su("", u, tty)
-# define log_su_failure(cu, u, tty) if(!cu) log_su("FAILED SU ", u, tty)
-# else
- /* partial logging */
-# if !defined( SYSLOG_SUCESS )
-# define log_su_successful(cu, u, tty)
-# define log_su_failure(cu, u, t) if(!cu) \
- syslog(LOG_NOTICE, "FAILED SU %s on %s", u, t)
-# else
-# define log_su_successful(cu, u, t) if(!cu) \
- syslog(LOG_NOTICE, "%s on %s", u, t)
-# define log_su_failure(cu, u, tty)
-# endif
-# endif
-#else
- /* logging not used */
-# define log_su_successful(cu, u, tty)
-# define log_su_failure(cu, u, tty)
-#endif
-
-
-int su_main ( int argc, char **argv )
-{
- unsigned long flags;
- int opt_preserve;
- int opt_loginshell;
- char *opt_shell = 0;
- char *opt_command = 0;
- char *opt_username = DEFAULT_USER;
- char **opt_args = 0;
+ unsigned flags;
+ char *opt_shell = NULL;
+ char *opt_command = NULL;
+ const char *opt_username = "root";
struct passwd *pw;
uid_t cur_uid = getuid();
-
-#if defined( SYSLOG_SUCCESS ) || defined( SYSLOG_FAILURE )
const char *tty;
- const char *old_user;
-#endif
+ char *old_user;
- flags = bb_getopt_ulflags(argc, argv, "mplc:s:",
- &opt_command, &opt_shell);
- opt_preserve = flags & 3;
- opt_loginshell = (flags & 4 ? 1 : 0);
+ flags = getopt32(argv, "mplc:s:", &opt_command, &opt_shell);
+ //argc -= optind;
+ argv += optind;
- if (optind < argc && argv[optind][0] == '-' && argv[optind][1] == 0) {
- opt_loginshell = 1;
- ++optind;
- }
+ if (argv[0] && LONE_DASH(argv[0])) {
+ flags |= SU_OPT_l;
+ argv++;
+ }
/* get user if specified */
- if ( optind < argc )
- opt_username = argv [optind++];
-
- if ( optind < argc )
- opt_args = argv + optind;
-
-#if defined( SYSLOG_SUCCESS ) || defined( SYSLOG_FAILURE )
-#ifdef CONFIG_FEATURE_UTMP
- /* The utmp entry (via getlogin) is probably the best way to identify
- the user, especially if someone su's from a su-shell. */
- old_user = getlogin ( );
- if ( !old_user )
-#endif
- {
- /* getlogin can fail -- usually due to lack of utmp entry. Resort to getpwuid. */
- pw = getpwuid ( cur_uid );
- old_user = ( pw ? pw->pw_name : "" );
+ if (argv[0]) {
+ opt_username = argv[0];
+ argv++;
}
- tty = ttyname ( 2 );
- if(!tty)
- tty = "none";
- openlog ( bb_applet_name, 0, LOG_AUTH );
-#endif
+ if (ENABLE_FEATURE_SU_SYSLOG) {
+ /* The utmp entry (via getlogin) is probably the best way to identify
+ the user, especially if someone su's from a su-shell.
+ But getlogin can fail -- usually due to lack of utmp entry.
+ in this case resort to getpwuid. */
+ old_user = xstrdup(IF_FEATURE_UTMP(getlogin() ? : ) (pw = getpwuid(cur_uid)) ? pw->pw_name : "");
+ tty = xmalloc_ttyname(2) ? : "none";
+ openlog(applet_name, 0, LOG_AUTH);
+ }
- pw = getpwnam ( opt_username );
- if ( !pw )
- bb_error_msg_and_die ( "user %s does not exist", opt_username );
+ pw = xgetpwnam(opt_username);
/* Make sure pw->pw_shell is non-NULL. It may be NULL when NEW_USER
is a username that is retrieved via NIS (YP), but that doesn't have
a default shell listed. */
- if ( !pw-> pw_shell || !pw->pw_shell [0] )
- pw-> pw_shell = (char *) DEFAULT_SHELL;
+ if (!pw->pw_shell || !pw->pw_shell[0])
+ pw->pw_shell = (char *)DEFAULT_SHELL;
- if ((( cur_uid == 0 ) || correct_password ( pw ))) {
- log_su_successful(pw->pw_uid, old_user, tty );
+ if ((cur_uid == 0) || correct_password(pw)) {
+ if (ENABLE_FEATURE_SU_SYSLOG)
+ syslog(LOG_NOTICE, "%c %s %s:%s",
+ '+', tty, old_user, opt_username);
} else {
- log_su_failure (pw->pw_uid, old_user, tty );
- bb_error_msg_and_die ( "incorrect password" );
+ if (ENABLE_FEATURE_SU_SYSLOG)
+ syslog(LOG_NOTICE, "%c %s %s:%s",
+ '-', tty, old_user, opt_username);
+ bb_error_msg_and_die("incorrect password");
}
-#if defined( SYSLOG_SUCCESS ) || defined( SYSLOG_FAILURE )
- closelog();
-#endif
+ if (ENABLE_FEATURE_CLEAN_UP && ENABLE_FEATURE_SU_SYSLOG) {
+ closelog();
+ free(old_user);
+ }
- if ( !opt_shell && opt_preserve )
- opt_shell = getenv ( "SHELL" );
+ if (!opt_shell && (flags & SU_OPT_mp))
+ opt_shell = getenv("SHELL");
- if ( opt_shell && cur_uid && restricted_shell ( pw-> pw_shell )) {
+#if ENABLE_FEATURE_SU_CHECKS_SHELLS
+ if (opt_shell && cur_uid && restricted_shell(pw->pw_shell)) {
/* The user being su'd to has a nonstandard shell, and so is
probably a uucp account or has restricted access. Don't
compromise the account by allowing access with a standard
shell. */
- fputs ( "using restricted shell\n", stderr );
- opt_shell = 0;
+ bb_error_msg("using restricted shell");
+ opt_shell = NULL;
}
-
- if ( !opt_shell )
+#endif
+ if (!opt_shell)
opt_shell = pw->pw_shell;
- change_identity ( pw );
- setup_environment ( opt_shell, opt_loginshell, !opt_preserve, pw );
-#ifdef CONFIG_SELINUX
- set_current_security_context(NULL);
-#endif
- run_shell ( opt_shell, opt_loginshell, opt_command, (const char**)opt_args);
+ change_identity(pw);
+ /* setup_environment params: shell, clear_env, change_env, pw */
+ setup_environment(opt_shell, flags & SU_OPT_l, !(flags & SU_OPT_mp), pw);
+ IF_SELINUX(set_current_security_context(NULL);)
+
+ /* Never returns */
+ run_shell(opt_shell, flags & SU_OPT_l, opt_command, (const char**)argv);
- return EXIT_FAILURE;
+ /* return EXIT_FAILURE; - not reached */
}
projects / oweals / busybox.git / blobdiff