1 files changed, 74 insertions, 140 deletions

diff --git a/release/src/router/busybox/loginutils/su.c b/release/src/router/busybox/loginutils/su.c
index 85f5cbe7..de8c18d2 100644
--- a/release/src/router/busybox/loginutils/su.c
+++ b/release/src/router/busybox/loginutils/su.c
@@ -1,166 +1,100 @@
 /* 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_SHELL "/bin/sh"
-#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 to the user given by PW;
-   if SUCCESSFUL is nonzero, they gave the correct password, etc.  */
-
-static void log_su ( const struct passwd *pw, int successful )
+int su_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int su_main(int argc UNUSED_PARAM, char **argv)
 {
-	const char *old_user, *tty;
-
-#if !defined( SYSLOG_SUCESS )
-	if ( successful )
-		return;
-#endif
-#if !defined( SYSLOG_FAILURE )
-	if ( !successful )
-		return;
-#endif
-
-	if ( pw-> pw_uid ) // not to root -> ignored
-		return;
-
-	/* 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 ) {
-		/* getlogin can fail -- usually due to lack of utmp entry. Resort to getpwuid.  */
-		struct passwd *pwd = getpwuid ( getuid ( ));
-		old_user = ( pwd ? pwd-> pw_name : "" );
+	unsigned flags;
+	char *opt_shell = NULL;
+	char *opt_command = NULL;
+	const char *opt_username = "root";
+	struct passwd *pw;
+	uid_t cur_uid = getuid();
+	const char *tty;
+	char *old_user;
+
+	flags = getopt32(argv, "mplc:s:", &opt_command, &opt_shell);
+	//argc -= optind;
+	argv += optind;
+
+	if (argv[0] && LONE_DASH(argv[0])) {
+		flags |= SU_OPT_l;
+		argv++;
 	}
-	
-	tty = ttyname ( 2 );
-
-	openlog ( "su", 0, LOG_AUTH );
-	syslog ( LOG_NOTICE, "%s%s on %s", successful ? "" : "FAILED SU ", old_user, tty ? tty : "none" );
-}
-#endif
-
 
+	/* get user if specified */
+	if (argv[0]) {
+		opt_username = argv[0];
+		argv++;
+	}
 
-int su_main ( int argc, char **argv )
-{
-	int flag;
-	int opt_preserve = 0;
-	int opt_loginshell = 0;
-	char *opt_shell = 0;
-	char *opt_command = 0;
-	char *opt_username = DEFAULT_USER;
-	char **opt_args = 0;
-	struct passwd *pw, pw_copy;
-
-
-	while (( flag = getopt ( argc, argv, "c:lmps:" )) != -1 ) {
-		switch ( flag ) {
-		case 'c':
-			opt_command = optarg;
-			break;
-		case 'm':
-		case 'p':
-			opt_preserve = 1;
-			break;
-		case 's':
-			opt_shell = optarg;
-			break;
-		case 'l':
-			opt_loginshell = 1;
-			break;
-		default:
-			bb_show_usage( );
-			break;
-		}
+	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(USE_FEATURE_UTMP(getlogin() ? : ) (pw = getpwuid(cur_uid)) ? pw->pw_name : "");
+		tty = xmalloc_ttyname(2) ? : "none";
+		openlog(applet_name, 0, LOG_AUTH);
 	}
 
-	if (( optind < argc ) && ( argv [optind][0] == '-' ) && ( argv [optind][1] == 0 )) {
-		opt_loginshell = 1;
-		++optind;
-    }
+	pw = xgetpwnam(opt_username);
 
-	/* get user if specified */
-	if ( optind < argc ) 
-		opt_username = argv [optind++];
-
-	if ( optind < argc )
-		opt_args = argv + optind;
-		
-		
-	pw = getpwnam ( opt_username );
-	if ( !pw )
-		bb_error_msg_and_die ( "user %s does not exist", 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;
-
-	/* Make a copy of the password information and point pw at the local
-	   copy instead.  Otherwise, some systems (e.g. Linux) would clobber
-	   the static data through the getlogin call from log_su.  */
-	pw_copy = *pw;
-	pw = &pw_copy;
-	pw-> pw_name  = bb_xstrdup ( pw-> pw_name );
-	pw-> pw_dir   = bb_xstrdup ( pw-> pw_dir );
-	pw-> pw_shell = bb_xstrdup ( pw-> pw_shell );
-
-	if (( getuid ( ) == 0 ) || correct_password ( pw )) 
-		log_su ( pw, 1 );
-	else {
-		log_su ( pw, 0 );
-		bb_error_msg_and_die ( "incorrect password" );
+	if (!pw->pw_shell || !pw->pw_shell[0])
+		pw->pw_shell = (char *)DEFAULT_SHELL;
+
+	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 {
+		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 (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 && getuid ( ) && 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;
 	}
+#endif
+	if (!opt_shell)
+		opt_shell = pw->pw_shell;
 
-	if ( !opt_shell )
-		opt_shell = bb_xstrdup ( pw-> pw_shell );
+	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);
+	USE_SELINUX(set_current_security_context(NULL);)
 
-	change_identity ( pw );	
-	setup_environment ( opt_shell, opt_loginshell, !opt_preserve, pw );
-	run_shell ( opt_shell, opt_loginshell, opt_command, (const char**)opt_args
-#ifdef CONFIG_SELINUX
-	, 0
-#endif
-	);
-	
-	return EXIT_FAILURE;
+	/* Never returns */
+	run_shell(opt_shell, flags & SU_OPT_l, opt_command, (const char**)argv);
+
+	/* return EXIT_FAILURE; - not reached */
 }