| /* vi: set sw=4 ts=4: */ |
| |
| #include "busybox.h" |
| |
| #include <fcntl.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/time.h> |
| #include <sys/types.h> |
| #include <ctype.h> |
| #include <time.h> |
| |
| #include "pwd.h" |
| #include "grp.h" |
| |
| #include "tinylogin.h" |
| |
| |
| |
| /* 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 ) |
| { |
| 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 : "" ); |
| } |
| |
| tty = ttyname ( 2 ); |
| |
| openlog ( "su", 0, LOG_AUTH ); |
| syslog ( LOG_NOTICE, "%s%s on %s", successful ? "" : "FAILED SU ", old_user, tty ? tty : "none" ); |
| } |
| #endif |
| |
| |
| |
| 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: |
| show_usage ( ); |
| break; |
| } |
| } |
| |
| if (( optind < argc ) && ( argv [optind][0] == '-' ) && ( argv [optind][1] == 0 )) { |
| opt_loginshell = 1; |
| ++optind; |
| } |
| |
| /* get user if specified */ |
| if ( optind < argc ) |
| opt_username = argv [optind++]; |
| |
| if ( optind < argc ) |
| opt_args = argv + optind; |
| |
| |
| pw = getpwnam ( opt_username ); |
| if ( !pw ) |
| 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 = xstrdup ( pw-> pw_name ); |
| pw-> pw_dir = xstrdup ( pw-> pw_dir ); |
| pw-> pw_shell = xstrdup ( pw-> pw_shell ); |
| |
| if (( getuid ( ) == 0 ) || correct_password ( pw )) |
| log_su ( pw, 1 ); |
| else { |
| log_su ( pw, 0 ); |
| error_msg_and_die ( "incorrect password" ); |
| } |
| |
| if ( !opt_shell && opt_preserve ) |
| opt_shell = getenv ( "SHELL" ); |
| |
| if ( opt_shell && getuid ( ) && 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; |
| } |
| |
| if ( !opt_shell ) |
| opt_shell = xstrdup ( pw-> pw_shell ); |
| |
| change_identity ( pw ); |
| setup_environment ( opt_shell, opt_loginshell, !opt_preserve, pw ); |
| run_shell ( opt_shell, opt_loginshell, opt_command, opt_args ); |
| |
| return EXIT_FAILURE; |
| } |