1 /* id -- print real and effective UIDs and GIDs
2 Copyright (C) 1989-2009 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Arnold Robbins.
18 Major rewrite by David MacKenzie, djm@gnu.ai.mit.edu. */
22 #include <sys/types.h>
26 #include <selinux/selinux.h>
30 #include "mgetgroups.h"
32 #include "group-list.h"
34 /* The official name of this program (e.g., no `g' prefix). */
35 #define PROGRAM_NAME "id"
38 proper_name ("Arnold Robbins"), \
39 proper_name ("David MacKenzie")
41 /* If nonzero, output only the SELinux context. -Z */
42 static int just_context
= 0;
44 static void print_user (uid_t uid
);
45 static void print_full_info (const char *username
);
47 /* If true, output user/group name instead of ID number. -n */
48 static bool use_name
= false;
50 /* The real and effective IDs of the user to print. */
51 static uid_t ruid
, euid
;
52 static gid_t rgid
, egid
;
54 /* True unless errors have been encountered. */
55 static bool ok
= true;
57 /* The SELinux context. Start with a known invalid value so print_full_info
58 knows when `context' has not been set to a meaningful value. */
59 static security_context_t context
= NULL
;
61 static struct option
const longopts
[] =
63 {"context", no_argument
, NULL
, 'Z'},
64 {"group", no_argument
, NULL
, 'g'},
65 {"groups", no_argument
, NULL
, 'G'},
66 {"name", no_argument
, NULL
, 'n'},
67 {"real", no_argument
, NULL
, 'r'},
68 {"user", no_argument
, NULL
, 'u'},
69 {GETOPT_HELP_OPTION_DECL
},
70 {GETOPT_VERSION_OPTION_DECL
},
77 if (status
!= EXIT_SUCCESS
)
78 fprintf (stderr
, _("Try `%s --help' for more information.\n"),
82 printf (_("Usage: %s [OPTION]... [USERNAME]\n"), program_name
);
84 Print user and group information for the specified USERNAME,\n\
85 or (when USERNAME omitted) for the current user.\n\
87 -a ignore, for compatibility with other versions\n\
88 -Z, --context print only the security context of the current user\n\
89 -g, --group print only the effective group ID\n\
90 -G, --groups print all group IDs\n\
91 -n, --name print a name instead of a number, for -ugG\n\
92 -r, --real print the real ID instead of the effective ID, with -ugG\n\
93 -u, --user print only the effective user ID\n\
95 fputs (HELP_OPTION_DESCRIPTION
, stdout
);
96 fputs (VERSION_OPTION_DESCRIPTION
, stdout
);
99 Without any OPTION, print some useful set of identified information.\n\
101 emit_bug_reporting_address ();
107 main (int argc
, char **argv
)
110 int selinux_enabled
= (is_selinux_enabled () > 0);
112 /* If true, output the list of all group IDs. -G */
113 bool just_group_list
= false;
114 /* If true, output only the group ID(s). -g */
115 bool just_group
= false;
116 /* If true, output real UID/GID instead of default effective UID/GID. -r */
117 bool use_real
= false;
118 /* If true, output only the user ID(s). -u */
119 bool just_user
= false;
121 initialize_main (&argc
, &argv
);
122 set_program_name (argv
[0]);
123 setlocale (LC_ALL
, "");
124 bindtextdomain (PACKAGE
, LOCALEDIR
);
125 textdomain (PACKAGE
);
127 atexit (close_stdout
);
129 while ((optc
= getopt_long (argc
, argv
, "agnruGZ", longopts
, NULL
)) != -1)
134 /* Ignore -a, for compatibility with SVR4. */
138 /* politely decline if we're not on a selinux-enabled kernel. */
139 if (!selinux_enabled
)
140 error (EXIT_FAILURE
, 0,
141 _("--context (-Z) works only on an SELinux-enabled kernel"));
158 just_group_list
= true;
160 case_GETOPT_HELP_CHAR
;
161 case_GETOPT_VERSION_CHAR (PROGRAM_NAME
, AUTHORS
);
163 usage (EXIT_FAILURE
);
167 if (1 < argc
- optind
)
169 error (0, 0, _("extra operand %s"), quote (argv
[optind
+ 1]));
170 usage (EXIT_FAILURE
);
173 if (argc
- optind
== 1 && just_context
)
174 error (EXIT_FAILURE
, 0,
175 _("cannot print security context when user specified"));
177 /* If we are on a selinux-enabled kernel and no user is specified,
178 get our context. Otherwise, leave the context variable alone -
179 it has been initialized known invalid value and will be not
180 displayed in print_full_info() */
181 if (selinux_enabled
&& argc
== optind
)
183 if (getcon (&context
) && just_context
)
184 error (EXIT_FAILURE
, 0, _("can't get process context"));
187 if (just_user
+ just_group
+ just_group_list
+ just_context
> 1)
188 error (EXIT_FAILURE
, 0, _("cannot print \"only\" of more than one choice"));
190 if (just_user
+ just_group
+ just_group_list
== 0 && (use_real
| use_name
))
191 error (EXIT_FAILURE
, 0,
192 _("cannot print only names or real IDs in default format"));
194 if (argc
- optind
== 1)
196 struct passwd
*pwd
= getpwnam (argv
[optind
]);
198 error (EXIT_FAILURE
, 0, _("%s: No such user"), argv
[optind
]);
199 ruid
= euid
= pwd
->pw_uid
;
200 rgid
= egid
= pwd
->pw_gid
;
212 print_user (use_real
? ruid
: euid
);
216 if (!print_group (use_real
? rgid
: egid
, use_name
))
219 else if (just_group_list
)
221 if (!print_group_list (argv
[optind
], ruid
, rgid
, egid
, use_name
))
224 else if (just_context
)
226 fputs (context
, stdout
);
230 print_full_info (argv
[optind
]);
234 exit (ok
? EXIT_SUCCESS
: EXIT_FAILURE
);
237 /* Print the name or value of user ID UID. */
240 print_user (uid_t uid
)
242 struct passwd
*pwd
= NULL
;
246 pwd
= getpwuid (uid
);
249 error (0, 0, _("cannot find name for user ID %lu"),
250 (unsigned long int) uid
);
256 printf ("%lu", (unsigned long int) uid
);
258 printf ("%s", pwd
->pw_name
);
261 /* Print all of the info about the user's user and group IDs. */
264 print_full_info (const char *username
)
269 printf (_("uid=%lu"), (unsigned long int) ruid
);
270 pwd
= getpwuid (ruid
);
272 printf ("(%s)", pwd
->pw_name
);
274 printf (_(" gid=%lu"), (unsigned long int) rgid
);
275 grp
= getgrgid (rgid
);
277 printf ("(%s)", grp
->gr_name
);
281 printf (_(" euid=%lu"), (unsigned long int) euid
);
282 pwd
= getpwuid (euid
);
284 printf ("(%s)", pwd
->pw_name
);
289 printf (_(" egid=%lu"), (unsigned long int) egid
);
290 grp
= getgrgid (egid
);
292 printf ("(%s)", grp
->gr_name
);
300 int n_groups
= mgetgroups (username
, (pwd
? pwd
->pw_gid
: (gid_t
) -1),
306 error (0, errno
, _("failed to get groups for user %s"),
311 error (0, errno
, _("failed to get groups for the current process"));
318 fputs (_(" groups="), stdout
);
319 for (i
= 0; i
< n_groups
; i
++)
323 printf ("%lu", (unsigned long int) groups
[i
]);
324 grp
= getgrgid (groups
[i
]);
326 printf ("(%s)", grp
->gr_name
);
330 #endif /* HAVE_GETGROUPS */
332 printf (_(" context=%s"), context
);