xref: /netbsd-src/usr.bin/id/id.c (revision bcc8ec9959e7b01e313d813067bfb43a3ad70551)
1 /*-
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __COPYRIGHT("@(#) Copyright (c) 1991, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n");
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)id.c	8.3 (Berkeley) 4/28/95";
43 #else
44 __RCSID("$NetBSD: id.c,v 1.17 2001/01/05 03:08:23 itohy Exp $");
45 #endif
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 
50 #include <err.h>
51 #include <errno.h>
52 #include <grp.h>
53 #include <pwd.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 
59 int	main __P((int, char **));
60 
61 static void	current __P((void));
62 static void	pretty __P((struct passwd *));
63 static void	group __P((struct passwd *, int));
64 static void	usage __P((void));
65 static void	user __P((struct passwd *));
66 static struct passwd *who __P((char *));
67 
68 static int maxgroups;
69 static gid_t *groups;
70 
71 int
72 main(argc, argv)
73 	int argc;
74 	char *argv[];
75 {
76 	struct group *gr;
77 	struct passwd *pw;
78 	int ch, id;
79 	int Gflag, gflag, nflag, pflag, rflag, uflag;
80 	extern const char *__progname;
81 
82 	Gflag = gflag = nflag = pflag = rflag = uflag = 0;
83 
84 	if (!strcmp(__progname, "groups")) {
85 		Gflag = 1;
86 		nflag = 1;
87 	} else if (!strcmp(__progname, "whoami")) {
88 		uflag = 1;
89 		nflag = 1;
90 	}
91 
92 	while ((ch = getopt(argc, argv, "Ggnpru")) != -1)
93 		switch(ch) {
94 		case 'G':
95 			Gflag = 1;
96 			break;
97 		case 'g':
98 			gflag = 1;
99 			break;
100 		case 'n':
101 			nflag = 1;
102 			break;
103 		case 'p':
104 			pflag = 1;
105 			break;
106 		case 'r':
107 			rflag = 1;
108 			break;
109 		case 'u':
110 			uflag = 1;
111 			break;
112 		case '?':
113 		default:
114 			usage();
115 		}
116 	argc -= optind;
117 	argv += optind;
118 
119 	switch(Gflag + gflag + pflag + uflag) {
120 	case 1:
121 		break;
122 	case 0:
123 		if (!nflag && !rflag)
124 			break;
125 		/* FALLTHROUGH */
126 	default:
127 		usage();
128 	}
129 
130 	pw = *argv ? who(*argv) : NULL;
131 
132 	maxgroups = sysconf(_SC_NGROUPS_MAX);
133 	if ((groups = malloc((maxgroups + 1) * sizeof(gid_t))) == NULL)
134 		err(1, NULL);
135 
136 	if (gflag) {
137 		id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
138 		if (nflag && (gr = getgrgid(id)))
139 			(void)printf("%s\n", gr->gr_name);
140 		else
141 			(void)printf("%u\n", id);
142 		goto done;
143 	}
144 
145 	if (uflag) {
146 		id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
147 		if (nflag && (pw = getpwuid(id)))
148 			(void)printf("%s\n", pw->pw_name);
149 		else
150 			(void)printf("%u\n", id);
151 		goto done;
152 	}
153 
154 	if (Gflag) {
155 		group(pw, nflag);
156 		goto done;
157 	}
158 
159 	if (pflag) {
160 		pretty(pw);
161 		goto done;
162 	}
163 
164 	if (pw)
165 		user(pw);
166 	else
167 		current();
168 done:
169 	free(groups);
170 	return(0);
171 }
172 
173 static void
174 pretty(pw)
175 	struct passwd *pw;
176 {
177 	struct group *gr;
178 	u_int eid, rid;
179 	char *login;
180 
181 	if (pw) {
182 		(void)printf("uid\t%s\n", pw->pw_name);
183 		(void)printf("groups\t");
184 		group(pw, 1);
185 	} else {
186 		if ((login = getlogin()) == NULL)
187 			err(1, "getlogin");
188 
189 		pw = getpwuid(rid = getuid());
190 		if (pw == NULL || strcmp(login, pw->pw_name))
191 			(void)printf("login\t%s\n", login);
192 		if (pw)
193 			(void)printf("uid\t%s\n", pw->pw_name);
194 		else
195 			(void)printf("uid\t%u\n", rid);
196 
197 		if ((eid = geteuid()) != rid) {
198 			if ((pw = getpwuid(eid)) != NULL)
199 				(void)printf("euid\t%s\n", pw->pw_name);
200 			else
201 				(void)printf("euid\t%u\n", eid);
202 		}
203 		if ((rid = getgid()) != (eid = getegid())) {
204 			if ((gr = getgrgid(rid)) != NULL)
205 				(void)printf("rgid\t%s\n", gr->gr_name);
206 			else
207 				(void)printf("rgid\t%u\n", rid);
208 		}
209 		(void)printf("groups\t");
210 		group(NULL, 1);
211 	}
212 }
213 
214 static void
215 current()
216 {
217 	struct group *gr;
218 	struct passwd *pw;
219 	int cnt, id, eid, lastid, ngroups;
220 	char *fmt;
221 
222 	id = getuid();
223 	(void)printf("uid=%u", id);
224 	if ((pw = getpwuid(id)) != NULL)
225 		(void)printf("(%s)", pw->pw_name);
226 	if ((eid = geteuid()) != id) {
227 		(void)printf(" euid=%u", eid);
228 		if ((pw = getpwuid(eid)) != NULL)
229 			(void)printf("(%s)", pw->pw_name);
230 	}
231 	id = getgid();
232 	(void)printf(" gid=%u", id);
233 	if ((gr = getgrgid(id)) != NULL)
234 		(void)printf("(%s)", gr->gr_name);
235 	if ((eid = getegid()) != id) {
236 		(void)printf(" egid=%u", eid);
237 		if ((gr = getgrgid(eid)) != NULL)
238 			(void)printf("(%s)", gr->gr_name);
239 	}
240 	if ((ngroups = getgroups(maxgroups, groups)) != NULL) {
241 		for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
242 		    fmt = ",%u", lastid = id, cnt++) {
243 			id = groups[cnt];
244 			if (lastid == id)
245 				continue;
246 			(void)printf(fmt, id);
247 			if ((gr = getgrgid(id)) != NULL)
248 				(void)printf("(%s)", gr->gr_name);
249 		}
250 	}
251 	(void)printf("\n");
252 }
253 
254 static void
255 user(pw)
256 	struct passwd *pw;
257 {
258 	struct group *gr;
259 	char *fmt;
260 	int cnt, id, lastid, ngroups;
261 
262 	id = pw->pw_uid;
263 	(void)printf("uid=%u(%s)", id, pw->pw_name);
264 	(void)printf(" gid=%lu", (u_long)pw->pw_gid);
265 	if ((gr = getgrgid(pw->pw_gid)) != NULL)
266 		(void)printf("(%s)", gr->gr_name);
267 	ngroups = maxgroups + 1;
268 	(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
269 	for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
270 	    fmt=",%u", lastid = id, cnt++) {
271 		id = groups[cnt];
272 		if (lastid == id)
273 			continue;
274 		(void)printf(fmt, id);
275 		if ((gr = getgrgid(id)) != NULL)
276 			(void)printf("(%s)", gr->gr_name);
277 	}
278 	(void)printf("\n");
279 }
280 
281 static void
282 group(pw, nflag)
283 	struct passwd *pw;
284 	int nflag;
285 {
286 	struct group *gr;
287 	int cnt, id, lastid, ngroups;
288 	char *fmt;
289 
290 	if (pw) {
291 		ngroups = maxgroups;
292 		(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
293 	} else {
294 		groups[0] = getgid();
295 		ngroups = getgroups(maxgroups, groups + 1) + 1;
296 	}
297 	fmt = nflag ? "%s" : "%u";
298 	for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
299 		if (lastid == (id = groups[cnt]))
300 			continue;
301 		if (nflag) {
302 			if ((gr = getgrgid(id)) != NULL)
303 				(void)printf(fmt, gr->gr_name);
304 			else
305 				(void)printf(*fmt == ' ' ? " %u" : "%u",
306 				    id);
307 			fmt = " %s";
308 		} else {
309 			(void)printf(fmt, id);
310 			fmt = " %u";
311 		}
312 		lastid = id;
313 	}
314 	(void)printf("\n");
315 }
316 
317 struct passwd *
318 who(u)
319 	char *u;
320 {
321 	struct passwd *pw;
322 	long id;
323 	char *ep;
324 
325 	/*
326 	 * Translate user argument into a pw pointer.  First, try to
327 	 * get it as specified.  If that fails, try it as a number.
328 	 */
329 	if ((pw = getpwnam(u)) != NULL)
330 		return(pw);
331 	id = strtol(u, &ep, 10);
332 	if (*u && !*ep && (pw = getpwuid(id)))
333 		return(pw);
334 	errx(1, "%s: No such user", u);
335 	/* NOTREACHED */
336 	return (NULL);
337 }
338 
339 void
340 usage()
341 {
342 	(void)fprintf(stderr, "usage: id [user]\n");
343 	(void)fprintf(stderr, "       id -G [-n] [user]\n");
344 	(void)fprintf(stderr, "       id -g [-nr] [user]\n");
345 	(void)fprintf(stderr, "       id -p\n");
346 	(void)fprintf(stderr, "       id -u [-nr] [user]\n");
347 	exit(1);
348 }
349