/* su for GNU. Run a shell with substitute user and group IDs.
- Copyright (C) 92, 93, 94, 1995 Free Software Foundation, Inc.
+ Copyright (C) 1992-2003 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Run a shell with the real and effective UID and GID and groups
of USER, default `root'.
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
+
+/* Hide any system prototype for getusershell.
+ This is necessary because some Cray systems have a conflicting
+ prototype (returning `int') in <unistd.h>. */
+#define getusershell _getusershell_sys_proto_
+
#include "system.h"
+#include "dirname.h"
-#if defined(HAVE_SYSLOG_H) && defined(HAVE_SYSLOG)
-#include <syslog.h>
-static void log_su ();
-#else /* !HAVE_SYSLOG_H */
-#ifdef SYSLOG_SUCCESS
-#undef SYSLOG_SUCCESS
-#endif
-#ifdef SYSLOG_FAILURE
-#undef SYSLOG_FAILURE
-#endif
-#ifdef SYSLOG_NON_ROOT
-#undef SYSLOG_NON_ROOT
+#undef getusershell
+
+#if HAVE_SYSLOG_H && HAVE_SYSLOG
+# include <syslog.h>
+#else
+# undef SYSLOG_SUCCESS
+# undef SYSLOG_FAILURE
+# undef SYSLOG_NON_ROOT
#endif
-#endif /* !HAVE_SYSLOG_H */
-#ifdef _POSIX_VERSION
-#include <limits.h>
-#else /* not _POSIX_VERSION */
-struct passwd *getpwuid ();
-struct group *getgrgid ();
-uid_t getuid ();
-#include <sys/param.h>
-#endif /* not _POSIX_VERSION */
+#if HAVE_SYS_PARAM_H
+# include <sys/param.h>
+#endif
#ifndef HAVE_ENDGRENT
# define endgrent() ((void) 0)
# define endpwent() ((void) 0)
#endif
-#ifdef HAVE_SHADOW_H
-#include <shadow.h>
+#if HAVE_SHADOW_H
+# include <shadow.h>
#endif
-#include "version.h"
#include "error.h"
+/* The official name of this program (e.g., no `g' prefix). */
+#define PROGRAM_NAME "su"
+
+#define WRITTEN_BY _("Written by David MacKenzie.")
+
+#if HAVE_PATHS_H
+# include <paths.h>
+#endif
+
/* The default PATH for simulated logins to non-superuser accounts. */
-#define DEFAULT_LOGIN_PATH ":/usr/ucb:/bin:/usr/bin"
+#ifdef _PATH_DEFPATH
+# define DEFAULT_LOGIN_PATH _PATH_DEFPATH
+#else
+# define DEFAULT_LOGIN_PATH ":/usr/ucb:/bin:/usr/bin"
+#endif
/* The default PATH for simulated logins to superuser accounts. */
-#define DEFAULT_ROOT_LOGIN_PATH "/usr/ucb:/bin:/usr/bin:/etc"
+#ifdef _PATH_DEFPATH_ROOT
+# define DEFAULT_ROOT_LOGIN_PATH _PATH_DEFPATH_ROOT
+#else
+# define DEFAULT_ROOT_LOGIN_PATH "/usr/ucb:/bin:/usr/bin:/etc"
+#endif
/* The shell to run if none is given in the user's passwd entry. */
#define DEFAULT_SHELL "/bin/sh"
void endusershell ();
void setusershell ();
-char *basename ();
-char *xmalloc ();
-char *xrealloc ();
-char *xstrdup ();
-
-static char *concat ();
-static int correct_password ();
-static int elements ();
-static int restricted_shell ();
-static void change_identity ();
-static void modify_environment ();
-static void run_shell ();
-static void usage ();
-static void xputenv ();
-
extern char **environ;
+static void run_shell (const char *, const char *, char **)
+ ATTRIBUTE_NORETURN;
+
/* The name this program was run with. */
char *program_name;
-/* If nonzero, display usage information and exit. */
-static int show_help;
-
-/* If nonzero, print the version on standard output and exit. */
-static int show_version;
-
/* If nonzero, pass the `-f' option to the subshell. */
static int fast_startup;
static struct option const longopts[] =
{
{"command", required_argument, 0, 'c'},
- {"fast", no_argument, &fast_startup, 1},
- {"help", no_argument, &show_help, 1},
- {"login", no_argument, &simulate_login, 1},
+ {"fast", no_argument, NULL, 'f'},
+ {"login", no_argument, NULL, 'l'},
{"preserve-environment", no_argument, &change_environment, 0},
{"shell", required_argument, 0, 's'},
- {"version", no_argument, &show_version, 1},
+ {GETOPT_HELP_OPTION_DECL},
+ {GETOPT_VERSION_OPTION_DECL},
{0, 0, 0, 0}
};
-void
-main (argc, argv)
- int argc;
- char **argv;
-{
- int optc;
- const char *new_user = DEFAULT_USER;
- char *command = 0;
- char **additional_args = 0;
- char *shell = 0;
- struct passwd *pw;
- struct passwd pw_copy;
-
- program_name = argv[0];
- setlocale (LC_ALL, "");
- bindtextdomain (PACKAGE, LOCALEDIR);
- textdomain (PACKAGE);
-
- fast_startup = 0;
- simulate_login = 0;
- change_environment = 1;
-
- while ((optc = getopt_long (argc, argv, "c:flmps:", longopts, (int *) 0))
- != EOF)
- {
- switch (optc)
- {
- case 0:
- break;
-
- case 'c':
- command = optarg;
- break;
-
- case 'f':
- fast_startup = 1;
- break;
+/* Add VAL to the environment, checking for out of memory errors. */
- case 'l':
- simulate_login = 1;
- break;
+static void
+xputenv (char *val)
+{
+ if (putenv (val))
+ xalloc_die ();
+}
- case 'm':
- case 'p':
- change_environment = 0;
- break;
+/* Return a newly-allocated string whose contents concatenate
+ those of S1, S2, S3. */
- case 's':
- shell = optarg;
- break;
+static char *
+concat (const char *s1, const char *s2, const char *s3)
+{
+ int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
+ char *result = xmalloc (len1 + len2 + len3 + 1);
- default:
- usage (1);
- }
- }
+ strcpy (result, s1);
+ strcpy (result + len1, s2);
+ strcpy (result + len1 + len2, s3);
+ result[len1 + len2 + len3] = 0;
- if (show_version)
- {
- printf ("su - %s\n", version_string);
- exit (0);
- }
+ return result;
+}
- if (show_help)
- usage (0);
+/* Return the number of elements in ARR, a null-terminated array. */
- if (optind < argc && !strcmp (argv[optind], "-"))
- {
- simulate_login = 1;
- ++optind;
- }
- if (optind < argc)
- new_user = argv[optind++];
- if (optind < argc)
- additional_args = argv + optind;
+static int
+elements (char **arr)
+{
+ int n = 0;
- pw = getpwnam (new_user);
- if (pw == 0)
- error (1, 0, _("user %s does not exist"), new_user);
- endpwent ();
+ for (n = 0; *arr; ++arr)
+ ++n;
+ return n;
+}
- /* 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 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. */
- if (!correct_password (pw))
- {
-#ifdef SYSLOG_FAILURE
- log_su (pw, 0);
-#endif
- error (1, 0, _("incorrect password"));
- }
-#ifdef SYSLOG_SUCCESS
- else
- {
- log_su (pw, 1);
- }
-#endif
+static void
+log_su (const struct passwd *pw, int successful)
+{
+ const char *new_user, *old_user, *tty;
- if (pw->pw_shell == 0 || pw->pw_shell[0] == 0)
- pw->pw_shell = (char *) DEFAULT_SHELL;
- if (shell == 0 && change_environment == 0)
- shell = getenv ("SHELL");
- if (shell != 0 && 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. */
- error (0, 0, _("using restricted shell %s"), pw->pw_shell);
- shell = 0;
- }
- if (shell == 0)
+# ifndef SYSLOG_NON_ROOT
+ if (pw->pw_uid)
+ return;
+# endif
+ new_user = pw->pw_name;
+ /* 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 == NULL)
{
- shell = xstrdup (pw->pw_shell);
+ /* getlogin can fail -- usually due to lack of utmp entry.
+ Resort to getpwuid. */
+ struct passwd *pwd = getpwuid (getuid ());
+ old_user = (pwd ? pwd->pw_name : "");
}
- modify_environment (pw, shell);
-
- change_identity (pw);
- if (simulate_login && chdir (pw->pw_dir))
- error (0, errno, _("warning: cannot change directory to %s"), pw->pw_dir);
-
- run_shell (shell, command, additional_args);
+ tty = ttyname (2);
+ if (tty == NULL)
+ tty = "none";
+ /* 4.2BSD openlog doesn't have the third parameter. */
+ openlog (base_name (program_name), 0
+# ifdef LOG_AUTH
+ , LOG_AUTH
+# endif
+ );
+ syslog (LOG_NOTICE,
+# ifdef SYSLOG_NON_ROOT
+ "%s(to %s) %s on %s",
+# else
+ "%s%s on %s",
+# endif
+ successful ? "" : "FAILED SU ",
+# ifdef SYSLOG_NON_ROOT
+ new_user,
+# endif
+ old_user, tty);
+ closelog ();
}
+#endif
/* Ask the user for a password.
Return 1 if the user gives the correct password for entry PW,
or if PW has an empty password. */
static int
-correct_password (pw)
- struct passwd *pw;
+correct_password (const struct passwd *pw)
{
char *unencrypted, *encrypted, *correct;
-#ifdef HAVE_SHADOW_H
+#if HAVE_GETSPNAM && HAVE_STRUCT_SPWD_SP_PWDP
/* Shadow passwd stuff for SVR3 and maybe other systems. */
struct spwd *sp = getspnam (pw->pw_name);
correct = sp->sp_pwdp;
else
#endif
- correct = pw->pw_passwd;
+ correct = pw->pw_passwd;
if (getuid () == 0 || correct == 0 || correct[0] == '\0')
return 1;
the value for the SHELL environment variable. */
static void
-modify_environment (pw, shell)
- struct passwd *pw;
- char *shell;
+modify_environment (const struct passwd *pw, const char *shell)
{
char *term;
/* Leave TERM unchanged. Set HOME, SHELL, USER, LOGNAME, PATH.
Unset all other environment variables. */
term = getenv ("TERM");
- environ = (char **) xmalloc (2 * sizeof (char *));
+ environ = xmalloc (2 * sizeof (char *));
environ[0] = 0;
if (term)
xputenv (concat ("TERM", "=", term));
xputenv (concat ("SHELL", "=", shell));
xputenv (concat ("USER", "=", pw->pw_name));
xputenv (concat ("LOGNAME", "=", pw->pw_name));
- xputenv (concat ("PATH", "=", pw->pw_uid
- ? DEFAULT_LOGIN_PATH : DEFAULT_ROOT_LOGIN_PATH));
+ xputenv (concat ("PATH", "=", (pw->pw_uid
+ ? DEFAULT_LOGIN_PATH
+ : DEFAULT_ROOT_LOGIN_PATH)));
}
else
{
/* Become the user and group(s) specified by PW. */
static void
-change_identity (pw)
- struct passwd *pw;
+change_identity (const struct passwd *pw)
{
#ifdef HAVE_INITGROUPS
errno = 0;
if (initgroups (pw->pw_name, pw->pw_gid) == -1)
- error (1, errno, _("cannot set groups"));
+ error (EXIT_FAILURE, errno, _("cannot set groups"));
endgrent ();
#endif
if (setgid (pw->pw_gid))
- error (1, errno, _("cannot set group id"));
+ error (EXIT_FAILURE, errno, _("cannot set group id"));
if (setuid (pw->pw_uid))
- error (1, errno, _("cannot set user id"));
+ error (EXIT_FAILURE, errno, _("cannot set user id"));
}
/* Run SHELL, or DEFAULT_SHELL if SHELL is empty.
arguments. */
static void
-run_shell (shell, command, additional_args)
- char *shell;
- char *command;
- char **additional_args;
+run_shell (const char *shell, const char *command, char **additional_args)
{
const char **args;
int argno = 1;
if (additional_args)
- args = (const char **) xmalloc (sizeof (char *)
+ args = xmalloc (sizeof (char *)
* (10 + elements (additional_args)));
else
- args = (const char **) xmalloc (sizeof (char *) * 10);
+ args = xmalloc (sizeof (char *) * 10);
if (simulate_login)
{
char *arg0;
char *shell_basename;
- shell_basename = basename (shell);
+ shell_basename = base_name (shell);
arg0 = xmalloc (strlen (shell_basename) + 2);
arg0[0] = '-';
strcpy (arg0 + 1, shell_basename);
args[0] = arg0;
}
else
- args[0] = basename (shell);
+ args[0] = base_name (shell);
if (fast_startup)
args[argno++] = "-f";
if (command)
args[argno++] = *additional_args;
args[argno] = NULL;
execv (shell, (char **) args);
- error (1, errno, _("cannot run %s"), shell);
-}
-
-#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 (pw, successful)
- struct passwd *pw;
- int successful;
-{
- const char *new_user, *old_user, *tty;
-#ifndef SYSLOG_NON_ROOT
- if (pw->pw_uid)
- return;
-#endif
- new_user = pw->pw_name;
- /* 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 == NULL)
- old_user = "";
- tty = ttyname (2);
- if (tty == NULL)
- tty = "";
- /* 4.2BSD openlog doesn't have the third parameter. */
- openlog (basename (program_name), 0
-#ifdef LOG_AUTH
- , LOG_AUTH
-#endif
- );
- syslog (LOG_NOTICE,
-#ifdef SYSLOG_NON_ROOT
- "%s(to %s) %s on %s",
-#else
- "%s%s on %s",
-#endif
- successful ? "" : "FAILED SU ",
-#ifdef SYSLOG_NON_ROOT
- new_user,
-#endif
- old_user, tty);
- closelog ();
+ {
+ int exit_status = (errno == ENOENT ? 127 : 126);
+ error (0, errno, "%s", shell);
+ exit (exit_status);
+ }
}
-#endif
/* Return 1 if SHELL is a restricted shell (one not returned by
getusershell), else 0, meaning it is a standard shell. */
static int
-restricted_shell (shell)
- char *shell;
+restricted_shell (const char *shell)
{
char *line;
return 1;
}
-/* Return the number of elements in ARR, a null-terminated array. */
-
-static int
-elements (arr)
- char **arr;
-{
- int n = 0;
-
- for (n = 0; *arr; ++arr)
- ++n;
- return n;
-}
-
-/* Add VAL to the environment, checking for out of memory errors. */
-
-static void
-xputenv (val)
- char *val;
-{
- if (putenv (val))
- error (1, 0, _("virtual memory exhausted"));
-}
-
-/* Return a newly-allocated string whose contents concatenate
- those of S1, S2, S3. */
-
-static char *
-concat (s1, s2, s3)
- char *s1, *s2, *s3;
-{
- int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
- char *result = (char *) xmalloc (len1 + len2 + len3 + 1);
-
- strcpy (result, s1);
- strcpy (result + len1, s2);
- strcpy (result + len1 + len2, s3);
- result[len1 + len2 + len3] = 0;
-
- return result;
-}
-
-static void
-usage (status)
- int status;
+void
+usage (int status)
{
if (status != 0)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
else
{
printf (_("Usage: %s [OPTION]... [-] [USER [ARG]...]\n"), program_name);
- printf (_("\
+ fputs (_("\
Change the effective user id and group id to that of USER.\n\
\n\
-, -l, --login make the shell a login shell\n\
-m, --preserve-environment do not reset environment variables\n\
-p same as -m\n\
-s, --shell=SHELL run SHELL if /etc/shells allows it\n\
- --help display this help and exit\n\
- --version output version information and exit\n\
+"), stdout);
+ fputs (HELP_OPTION_DESCRIPTION, stdout);
+ fputs (VERSION_OPTION_DESCRIPTION, stdout);
+ fputs (_("\
\n\
A mere - implies -l. If USER not given, assume root.\n\
-"));
+"), stdout);
+ printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
}
exit (status);
}
+
+int
+main (int argc, char **argv)
+{
+ int optc;
+ const char *new_user = DEFAULT_USER;
+ char *command = 0;
+ char **additional_args = 0;
+ char *shell = 0;
+ struct passwd *pw;
+ struct passwd pw_copy;
+
+ initialize_main (&argc, &argv);
+ program_name = argv[0];
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ atexit (close_stdout);
+
+ fast_startup = 0;
+ simulate_login = 0;
+ change_environment = 1;
+
+ while ((optc = getopt_long (argc, argv, "c:flmps:", longopts, NULL)) != -1)
+ {
+ switch (optc)
+ {
+ case 0:
+ break;
+
+ case 'c':
+ command = optarg;
+ break;
+
+ case 'f':
+ fast_startup = 1;
+ break;
+
+ case 'l':
+ simulate_login = 1;
+ break;
+
+ case 'm':
+ case 'p':
+ change_environment = 0;
+ break;
+
+ case 's':
+ shell = optarg;
+ break;
+
+ case_GETOPT_HELP_CHAR;
+
+ case_GETOPT_VERSION_CHAR (PROGRAM_NAME, WRITTEN_BY);
+
+ default:
+ usage (EXIT_FAILURE);
+ }
+ }
+
+ if (optind < argc && !strcmp (argv[optind], "-"))
+ {
+ simulate_login = 1;
+ ++optind;
+ }
+ if (optind < argc)
+ new_user = argv[optind++];
+ if (optind < argc)
+ additional_args = argv + optind;
+
+ pw = getpwnam (new_user);
+ if (pw == 0)
+ error (EXIT_FAILURE, 0, _("user %s does not exist"), new_user);
+ endpwent ();
+
+ /* 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 == NULL || pw->pw_shell[0] == '\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 (!correct_password (pw))
+ {
+#ifdef SYSLOG_FAILURE
+ log_su (pw, 0);
+#endif
+ error (EXIT_FAILURE, 0, _("incorrect password"));
+ }
+#ifdef SYSLOG_SUCCESS
+ else
+ {
+ log_su (pw, 1);
+ }
+#endif
+
+ if (shell == 0 && change_environment == 0)
+ shell = getenv ("SHELL");
+ if (shell != 0 && 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. */
+ error (0, 0, _("using restricted shell %s"), pw->pw_shell);
+ shell = 0;
+ }
+ if (shell == 0)
+ {
+ shell = xstrdup (pw->pw_shell);
+ }
+ modify_environment (pw, shell);
+
+ change_identity (pw);
+ if (simulate_login && chdir (pw->pw_dir))
+ error (0, errno, _("warning: cannot change directory to %s"), pw->pw_dir);
+
+ run_shell (shell, command, additional_args);
+}