Patch from Tito to make syslog configurable and remove #ifdefs. Further

cleanups by me.

2 files changed, 50 insertions, 111 deletions

diff --git a/loginutils/Config.in b/loginutils/Config.in
index 3bbb6d9..e920d5f 100644
--- a/loginutils/Config.in
+++ b/loginutils/Config.in
@@ -142,6 +142,13 @@ config CONFIG_SU
 	  Note that Busybox binary must be setuid root for this applet to
 	  work properly.
 
+config CONFIG_SU_SYSLOG
+	bool "Support for syslog in su"
+	default y
+	depends on CONFIG_SU
+	help
+	  Enables support for syslog in su.
+
 config CONFIG_SULOGIN
 	bool "sulogin"
 	default n
diff --git a/loginutils/su.c b/loginutils/su.c
index 1273831..bd3e7c5 100644
--- a/loginutils/su.c
+++ b/loginutils/su.c
@@ -1,86 +1,31 @@
 /* vi: set sw=4 ts=4: */
 /*
-   Licensed under the GPL v2, see the file LICENSE in this tarball.
-*/
+ *  Mini su implementation for busybox
+ *
+ *  Licensed under the GPL v2, see the file LICENSE in this tarball.
+ */
 
-#include <fcntl.h>
+#include "busybox.h"
 #include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include <syslog.h>
-#include <termios.h>
-#include <unistd.h>
-#include <utmp.h>
 #include <sys/resource.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <ctype.h>
 #include <time.h>
 
-#include "busybox.h"
-
-/* The shell to run if none is given in the user's passwd entry.  */
-#ifndef DEFAULT_SHELL
-#define DEFAULT_SHELL "/bin/sh"
-#endif
-
-/* Default user.  */
-#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)
-{
-	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;
 	char *opt_shell = 0;
 	char *opt_command = 0;
-	char *opt_username = DEFAULT_USER;
+	char *opt_username = "root";
 	char **opt_args = 0;
 	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);
-#define SU_OPT_m (3)
-#define SU_OPT_p (3)
+	flags = bb_getopt_ulflags(argc, argv, "mplc:s:", &opt_command, &opt_shell);
+#define SU_OPT_mp (3)
 #define SU_OPT_l (4)
 
 	if (optind < argc  && argv[optind][0] == '-' && argv[optind][1] == 0) {
@@ -89,73 +34,60 @@ int su_main ( int argc, char **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 (optind < argc) opt_username = argv [optind++];
+
+	if (optind < argc) opt_args = argv + optind;
+
+	if (ENABLE_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 = bb_xstrdup(USE_FEATURE_UTMP(getlogin() ? : ) (pw = getpwuid(cur_uid)) ? pw->pw_name : "");
+		tty = ttyname(2) ? : "none";
+		openlog(bb_applet_name, 0, LOG_AUTH);
 	}
-	tty = ttyname ( 2 );
-	if(!tty)
-		tty = "none";
 
-	openlog ( bb_applet_name, 0, LOG_AUTH );
-#endif
-
-	pw = getpwnam ( opt_username );
-	if ( !pw )
-		bb_error_msg_and_die ( "user %s does not exist", opt_username );
+	pw = getpwnam(opt_username);
+	if (!pw) bb_error_msg_and_die("Unknown id: %s", 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_SU_SYSLOG)
+			syslog(LOG_NOTICE, "+ %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_SU_SYSLOG)
+			syslog(LOG_NOTICE, "- %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_SU_SYSLOG) {
+		closelog();
+		free(old_user);
+	}
 
-	if ( !opt_shell && (flags & SU_OPT_p))
-		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 (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 );
+		bb_error_msg("using restricted shell");
 		opt_shell = 0;
 	}
 
-	if ( !opt_shell )
-		opt_shell = pw->pw_shell;
+	if (!opt_shell) opt_shell = pw->pw_shell;
+
+	change_identity(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, flags & SU_OPT_l, !(flags & SU_OPT_p), pw);
-#if ENABLE_SELINUX
-       set_current_security_context(NULL);
-#endif
+	/* Returns only on error */
 	run_shell(opt_shell, flags & SU_OPT_l, opt_command, (const char**)opt_args);
 
 	return EXIT_FAILURE;