xref: /netbsd/usr.bin/id/id.c (revision bf9ec67e) 
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 1.18 2001/02/19 23:03:47 cgd 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 
81 	Gflag = gflag = nflag = pflag = rflag = uflag = 0;
82 
83 	if (!strcmp(getprogname(), "groups")) {
84 		Gflag = 1;
85 		nflag = 1;
86 	} else if (!strcmp(getprogname(), "whoami")) {
87 		uflag = 1;
88 		nflag = 1;
89 	}
90 
91 	while ((ch = getopt(argc, argv, "Ggnpru")) != -1)
92 		switch(ch) {
93 		case 'G':
94 			Gflag = 1;
95 			break;
96 		case 'g':
97 			gflag = 1;
98 			break;
99 		case 'n':
100 			nflag = 1;
101 			break;
102 		case 'p':
103 			pflag = 1;
104 			break;
105 		case 'r':
106 			rflag = 1;
107 			break;
108 		case 'u':
109 			uflag = 1;
110 			break;
111 		case '?':
112 		default:
113 			usage();
114 		}
115 	argc -= optind;
116 	argv += optind;
117 
118 	switch(Gflag + gflag + pflag + uflag) {
119 	case 1:
120 		break;
121 	case 0:
122 		if (!nflag && !rflag)
123 			break;
124 		/* FALLTHROUGH */
125 	default:
126 		usage();
127 	}
128 
129 	pw = *argv ? who(*argv) : NULL;
130 
131 	maxgroups = sysconf(_SC_NGROUPS_MAX);
132 	if ((groups = malloc((maxgroups + 1) * sizeof(gid_t))) == NULL)
133 		err(1, NULL);
134 
135 	if (gflag) {
136 		id = pw ? pw->pw_gid : rflag ? getgid() : getegid();
137 		if (nflag && (gr = getgrgid(id)))
138 			(void)printf("%s\n", gr->gr_name);
139 		else
140 			(void)printf("%u\n", id);
141 		goto done;
142 	}
143 
144 	if (uflag) {
145 		id = pw ? pw->pw_uid : rflag ? getuid() : geteuid();
146 		if (nflag && (pw = getpwuid(id)))
147 			(void)printf("%s\n", pw->pw_name);
148 		else
149 			(void)printf("%u\n", id);
150 		goto done;
151 	}
152 
153 	if (Gflag) {
154 		group(pw, nflag);
155 		goto done;
156 	}
157 
158 	if (pflag) {
159 		pretty(pw);
160 		goto done;
161 	}
162 
163 	if (pw)
164 		user(pw);
165 	else
166 		current();
167 done:
168 	free(groups);
169 	return(0);
170 }
171 
172 static void
173 pretty(pw)
174 	struct passwd *pw;
175 {
176 	struct group *gr;
177 	u_int eid, rid;
178 	char *login;
179 
180 	if (pw) {
181 		(void)printf("uid\t%s\n", pw->pw_name);
182 		(void)printf("groups\t");
183 		group(pw, 1);
184 	} else {
185 		if ((login = getlogin()) == NULL)
186 			err(1, "getlogin");
187 
188 		pw = getpwuid(rid = getuid());
189 		if (pw == NULL || strcmp(login, pw->pw_name))
190 			(void)printf("login\t%s\n", login);
191 		if (pw)
192 			(void)printf("uid\t%s\n", pw->pw_name);
193 		else
194 			(void)printf("uid\t%u\n", rid);
195 
196 		if ((eid = geteuid()) != rid) {
197 			if ((pw = getpwuid(eid)) != NULL)
198 				(void)printf("euid\t%s\n", pw->pw_name);
199 			else
200 				(void)printf("euid\t%u\n", eid);
201 		}
202 		if ((rid = getgid()) != (eid = getegid())) {
203 			if ((gr = getgrgid(rid)) != NULL)
204 				(void)printf("rgid\t%s\n", gr->gr_name);
205 			else
206 				(void)printf("rgid\t%u\n", rid);
207 		}
208 		(void)printf("groups\t");
209 		group(NULL, 1);
210 	}
211 }
212 
213 static void
214 current()
215 {
216 	struct group *gr;
217 	struct passwd *pw;
218 	int cnt, id, eid, lastid, ngroups;
219 	char *fmt;
220 
221 	id = getuid();
222 	(void)printf("uid=%u", id);
223 	if ((pw = getpwuid(id)) != NULL)
224 		(void)printf("(%s)", pw->pw_name);
225 	if ((eid = geteuid()) != id) {
226 		(void)printf(" euid=%u", eid);
227 		if ((pw = getpwuid(eid)) != NULL)
228 			(void)printf("(%s)", pw->pw_name);
229 	}
230 	id = getgid();
231 	(void)printf(" gid=%u", id);
232 	if ((gr = getgrgid(id)) != NULL)
233 		(void)printf("(%s)", gr->gr_name);
234 	if ((eid = getegid()) != id) {
235 		(void)printf(" egid=%u", eid);
236 		if ((gr = getgrgid(eid)) != NULL)
237 			(void)printf("(%s)", gr->gr_name);
238 	}
239 	if ((ngroups = getgroups(maxgroups, groups)) != NULL) {
240 		for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
241 		    fmt = ",%u", lastid = id, cnt++) {
242 			id = groups[cnt];
243 			if (lastid == id)
244 				continue;
245 			(void)printf(fmt, id);
246 			if ((gr = getgrgid(id)) != NULL)
247 				(void)printf("(%s)", gr->gr_name);
248 		}
249 	}
250 	(void)printf("\n");
251 }
252 
253 static void
254 user(pw)
255 	struct passwd *pw;
256 {
257 	struct group *gr;
258 	char *fmt;
259 	int cnt, id, lastid, ngroups;
260 
261 	id = pw->pw_uid;
262 	(void)printf("uid=%u(%s)", id, pw->pw_name);
263 	(void)printf(" gid=%lu", (u_long)pw->pw_gid);
264 	if ((gr = getgrgid(pw->pw_gid)) != NULL)
265 		(void)printf("(%s)", gr->gr_name);
266 	ngroups = maxgroups + 1;
267 	(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
268 	for (fmt = " groups=%u", lastid = -1, cnt = 0; cnt < ngroups;
269 	    fmt=",%u", lastid = id, cnt++) {
270 		id = groups[cnt];
271 		if (lastid == id)
272 			continue;
273 		(void)printf(fmt, id);
274 		if ((gr = getgrgid(id)) != NULL)
275 			(void)printf("(%s)", gr->gr_name);
276 	}
277 	(void)printf("\n");
278 }
279 
280 static void
281 group(pw, nflag)
282 	struct passwd *pw;
283 	int nflag;
284 {
285 	struct group *gr;
286 	int cnt, id, lastid, ngroups;
287 	char *fmt;
288 
289 	if (pw) {
290 		ngroups = maxgroups;
291 		(void) getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
292 	} else {
293 		groups[0] = getgid();
294 		ngroups = getgroups(maxgroups, groups + 1) + 1;
295 	}
296 	fmt = nflag ? "%s" : "%u";
297 	for (lastid = -1, cnt = 0; cnt < ngroups; ++cnt) {
298 		if (lastid == (id = groups[cnt]))
299 			continue;
300 		if (nflag) {
301 			if ((gr = getgrgid(id)) != NULL)
302 				(void)printf(fmt, gr->gr_name);
303 			else
304 				(void)printf(*fmt == ' ' ? " %u" : "%u",
305 				    id);
306 			fmt = " %s";
307 		} else {
308 			(void)printf(fmt, id);
309 			fmt = " %u";
310 		}
311 		lastid = id;
312 	}
313 	(void)printf("\n");
314 }
315 
316 struct passwd *
317 who(u)
318 	char *u;
319 {
320 	struct passwd *pw;
321 	long id;
322 	char *ep;
323 
324 	/*
325 	 * Translate user argument into a pw pointer.  First, try to
326 	 * get it as specified.  If that fails, try it as a number.
327 	 */
328 	if ((pw = getpwnam(u)) != NULL)
329 		return(pw);
330 	id = strtol(u, &ep, 10);
331 	if (*u && !*ep && (pw = getpwuid(id)))
332 		return(pw);
333 	errx(1, "%s: No such user", u);
334 	/* NOTREACHED */
335 	return (NULL);
336 }
337 
338 void
339 usage()
340 {
341 	(void)fprintf(stderr, "usage: id [user]\n");
342 	(void)fprintf(stderr, "       id -G [-n] [user]\n");
343 	(void)fprintf(stderr, "       id -g [-nr] [user]\n");
344 	(void)fprintf(stderr, "       id -p\n");
345 	(void)fprintf(stderr, "       id -u [-nr] [user]\n");
346 	exit(1);
347 }
348