Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
| 2 | |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 3 | #include <fcntl.h> |
| 4 | #include <signal.h> |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <string.h> |
| 8 | #include <syslog.h> |
| 9 | #include <termios.h> |
| 10 | #include <unistd.h> |
| 11 | #include <utmp.h> |
| 12 | #include <sys/resource.h> |
| 13 | #include <sys/stat.h> |
| 14 | #include <sys/time.h> |
| 15 | #include <sys/types.h> |
| 16 | #include <ctype.h> |
| 17 | #include <time.h> |
| 18 | |
Eric Andersen | 27f64e1 | 2002-06-23 04:24:25 +0000 | [diff] [blame] | 19 | #include "busybox.h" |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 20 | |
| 21 | |
| 22 | |
| 23 | /* The shell to run if none is given in the user's passwd entry. */ |
| 24 | #define DEFAULT_SHELL "/bin/sh" |
| 25 | #define DEFAULT_USER "root" |
| 26 | |
| 27 | //#define SYSLOG_SUCCESS |
| 28 | #define SYSLOG_FAILURE |
| 29 | |
| 30 | |
| 31 | #if defined( SYSLOG_SUCCESS ) || defined( SYSLOG_FAILURE ) |
| 32 | /* Log the fact that someone has run su to the user given by PW; |
| 33 | if SUCCESSFUL is nonzero, they gave the correct password, etc. */ |
| 34 | |
| 35 | static void log_su ( const struct passwd *pw, int successful ) |
| 36 | { |
| 37 | const char *old_user, *tty; |
| 38 | |
| 39 | #if !defined( SYSLOG_SUCESS ) |
| 40 | if ( successful ) |
| 41 | return; |
| 42 | #endif |
| 43 | #if !defined( SYSLOG_FAILURE ) |
| 44 | if ( !successful ) |
| 45 | return; |
| 46 | #endif |
| 47 | |
| 48 | if ( pw-> pw_uid ) // not to root -> ignored |
| 49 | return; |
| 50 | |
| 51 | /* The utmp entry (via getlogin) is probably the best way to identify |
| 52 | the user, especially if someone su's from a su-shell. */ |
| 53 | old_user = getlogin ( ); |
| 54 | if ( !old_user ) { |
| 55 | /* getlogin can fail -- usually due to lack of utmp entry. Resort to getpwuid. */ |
| 56 | struct passwd *pwd = getpwuid ( getuid ( )); |
| 57 | old_user = ( pwd ? pwd-> pw_name : "" ); |
| 58 | } |
| 59 | |
| 60 | tty = ttyname ( 2 ); |
| 61 | |
| 62 | openlog ( "su", 0, LOG_AUTH ); |
| 63 | syslog ( LOG_NOTICE, "%s%s on %s", successful ? "" : "FAILED SU ", old_user, tty ? tty : "none" ); |
| 64 | } |
| 65 | #endif |
| 66 | |
| 67 | |
| 68 | |
| 69 | int su_main ( int argc, char **argv ) |
| 70 | { |
| 71 | int flag; |
| 72 | int opt_preserve = 0; |
| 73 | int opt_loginshell = 0; |
| 74 | char *opt_shell = 0; |
| 75 | char *opt_command = 0; |
| 76 | char *opt_username = DEFAULT_USER; |
| 77 | char **opt_args = 0; |
| 78 | struct passwd *pw, pw_copy; |
| 79 | |
| 80 | |
| 81 | while (( flag = getopt ( argc, argv, "c:lmps:" )) != -1 ) { |
| 82 | switch ( flag ) { |
| 83 | case 'c': |
| 84 | opt_command = optarg; |
| 85 | break; |
| 86 | case 'm': |
| 87 | case 'p': |
| 88 | opt_preserve = 1; |
| 89 | break; |
| 90 | case 's': |
| 91 | opt_shell = optarg; |
| 92 | break; |
| 93 | case 'l': |
| 94 | opt_loginshell = 1; |
| 95 | break; |
| 96 | default: |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 97 | bb_show_usage( ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 98 | break; |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | if (( optind < argc ) && ( argv [optind][0] == '-' ) && ( argv [optind][1] == 0 )) { |
| 103 | opt_loginshell = 1; |
| 104 | ++optind; |
| 105 | } |
| 106 | |
| 107 | /* get user if specified */ |
| 108 | if ( optind < argc ) |
| 109 | opt_username = argv [optind++]; |
| 110 | |
| 111 | if ( optind < argc ) |
| 112 | opt_args = argv + optind; |
| 113 | |
| 114 | |
| 115 | pw = getpwnam ( opt_username ); |
| 116 | if ( !pw ) |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 117 | bb_error_msg_and_die ( "user %s does not exist", opt_username ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 118 | |
| 119 | /* Make sure pw->pw_shell is non-NULL. It may be NULL when NEW_USER |
| 120 | is a username that is retrieved via NIS (YP), but that doesn't have |
| 121 | a default shell listed. */ |
| 122 | if ( !pw-> pw_shell || !pw->pw_shell [0] ) |
| 123 | pw-> pw_shell = (char *) DEFAULT_SHELL; |
| 124 | |
| 125 | /* Make a copy of the password information and point pw at the local |
| 126 | copy instead. Otherwise, some systems (e.g. Linux) would clobber |
| 127 | the static data through the getlogin call from log_su. */ |
| 128 | pw_copy = *pw; |
| 129 | pw = &pw_copy; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 130 | pw-> pw_name = bb_xstrdup ( pw-> pw_name ); |
| 131 | pw-> pw_dir = bb_xstrdup ( pw-> pw_dir ); |
| 132 | pw-> pw_shell = bb_xstrdup ( pw-> pw_shell ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 133 | |
| 134 | if (( getuid ( ) == 0 ) || correct_password ( pw )) |
| 135 | log_su ( pw, 1 ); |
| 136 | else { |
| 137 | log_su ( pw, 0 ); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 138 | bb_error_msg_and_die ( "incorrect password" ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 139 | } |
| 140 | |
| 141 | if ( !opt_shell && opt_preserve ) |
| 142 | opt_shell = getenv ( "SHELL" ); |
| 143 | |
| 144 | if ( opt_shell && getuid ( ) && restricted_shell ( pw-> pw_shell )) |
| 145 | { |
| 146 | /* The user being su'd to has a nonstandard shell, and so is |
| 147 | probably a uucp account or has restricted access. Don't |
| 148 | compromise the account by allowing access with a standard |
| 149 | shell. */ |
| 150 | fputs ( "using restricted shell\n", stderr ); |
| 151 | opt_shell = 0; |
| 152 | } |
| 153 | |
| 154 | if ( !opt_shell ) |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 155 | opt_shell = bb_xstrdup ( pw-> pw_shell ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 156 | |
| 157 | change_identity ( pw ); |
| 158 | setup_environment ( opt_shell, opt_loginshell, !opt_preserve, pw ); |
Eric Andersen | 9e48045 | 2003-07-03 10:07:04 +0000 | [diff] [blame^] | 159 | run_shell ( opt_shell, opt_loginshell, opt_command, (const char**)opt_args |
| 160 | #ifdef CONFIG_SELINUX |
| 161 | , 0 |
| 162 | #endif |
| 163 | ); |
Robert Griebl | 1fca558 | 2002-06-04 20:45:46 +0000 | [diff] [blame] | 164 | |
| 165 | return EXIT_FAILURE; |
| 166 | } |