xref: /freebsd/usr.bin/finger/finger.c (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 /*
38  * Luke Mewburn <lm@rmit.edu.au> added the following on 940622:
39  *    - mail status ("No Mail", "Mail read:...", or "New Mail ...,
40  *	Unread since ...".)
41  *    - 4 digit phone extensions (3210 is printed as x3210.)
42  *    - host/office toggling in short format with -h & -o.
43  *    - short day names (`Tue' printed instead of `Jun 21' if the
44  *	login time is < 6 days.
45  */
46 
47 #ifndef lint
48 static const char copyright[] =
49 "@(#) Copyright (c) 1989, 1993\n\
50 	The Regents of the University of California.  All rights reserved.\n";
51 #endif /* not lint */
52 
53 #if 0
54 #ifndef lint
55 static char sccsid[] = "@(#)finger.c	8.5 (Berkeley) 5/4/95";
56 #endif
57 #endif
58 
59 #include <sys/cdefs.h>
60 __FBSDID("$FreeBSD$");
61 
62 /*
63  * Finger prints out information about users.  It is not portable since
64  * certain fields (e.g. the full user name, office, and phone numbers) are
65  * extracted from the gecos field of the passwd file which other UNIXes
66  * may not have or may use for other things.
67  *
68  * There are currently two output formats; the short format is one line
69  * per user and displays login name, tty, login time, real name, idle time,
70  * and either remote host information (default) or office location/phone
71  * number, depending on if -h or -o is used respectively.
72  * The long format gives the same information (in a more legible format) as
73  * well as home directory, shell, mail info, and .plan/.project files.
74  */
75 
76 #include <sys/types.h>
77 #include <sys/socket.h>
78 #include <db.h>
79 #include <err.h>
80 #include <pwd.h>
81 #include <stdio.h>
82 #include <stdlib.h>
83 #include <string.h>
84 #include <time.h>
85 #include <unistd.h>
86 #include <utmp.h>
87 #include <locale.h>
88 
89 #include "finger.h"
90 #include "pathnames.h"
91 
92 DB *db;
93 time_t now;
94 int entries, gflag, kflag, lflag, mflag, pplan, sflag, oflag, Tflag;
95 sa_family_t family = PF_UNSPEC;
96 int d_first = -1;
97 char tbuf[1024];
98 int invoker_root = 0;
99 
100 static void loginlist(void);
101 static int option(int, char **);
102 static void usage(void);
103 static void userlist(int, char **);
104 
105 static int
106 option(int argc, char **argv)
107 {
108 	int ch;
109 
110 	optind = 1;		/* reset getopt */
111 
112 	while ((ch = getopt(argc, argv, "46gklmpshoT")) != -1)
113 		switch(ch) {
114 		case '4':
115 			family = AF_INET;
116 			break;
117 		case '6':
118 			family = AF_INET6;
119 			break;
120 		case 'g':
121 			gflag = 1;
122 			break;
123 		case 'k':
124 			kflag = 1;		/* keep going without utmp */
125 			break;
126 		case 'l':
127 			lflag = 1;		/* long format */
128 			break;
129 		case 'm':
130 			mflag = 1;		/* force exact match of names */
131 			break;
132 		case 'p':
133 			pplan = 1;		/* don't show .plan/.project */
134 			break;
135 		case 's':
136 			sflag = 1;		/* short format */
137 			break;
138 		case 'h':
139 			oflag = 0;		/* remote host info */
140 			break;
141 		case 'o':
142 			oflag = 1;		/* office info */
143 			break;
144 		case 'T':
145 			Tflag = 1;		/* disable T/TCP */
146 			break;
147 		case '?':
148 		default:
149 			usage();
150 		}
151 
152 	return optind;
153 }
154 
155 static void
156 usage(void)
157 {
158 	(void)fprintf(stderr,
159 	    "usage: finger [-46gklmpshoT] [user ...] [user@host ...]\n");
160 	exit(1);
161 }
162 
163 int
164 main(int argc, char **argv)
165 {
166 	int envargc, argcnt;
167 	char *envargv[3];
168 	struct passwd *pw;
169 	static char myname[] = "finger";
170 
171 	if (getuid() == 0 || geteuid() == 0) {
172 		invoker_root = 1;
173 		if ((pw = getpwnam(UNPRIV_NAME)) && pw->pw_uid > 0) {
174 			 setgid(pw->pw_gid);
175 			 setuid(pw->pw_uid);
176 		} else {
177 			 setgid(UNPRIV_UGID);
178 			 setuid(UNPRIV_UGID);
179 		}
180 	}
181 
182 	(void) setlocale(LC_ALL, "");
183 
184 				/* remove this line to get remote host */
185 	oflag = 1;		/* default to old "office" behavior */
186 
187 	/*
188 	 * Process environment variables followed by command line arguments.
189 	 */
190 	if ((envargv[1] = getenv("FINGER"))) {
191 		envargc = 2;
192 		envargv[0] = myname;
193 		envargv[2] = NULL;
194 		(void) option(envargc, envargv);
195 	}
196 
197 	argcnt = option(argc, argv);
198 	argc -= argcnt;
199 	argv += argcnt;
200 
201 	(void)time(&now);
202 	setpassent(1);
203 	if (!*argv) {
204 		/*
205 		 * Assign explicit "small" format if no names given and -l
206 		 * not selected.  Force the -s BEFORE we get names so proper
207 		 * screening will be done.
208 		 */
209 		if (!lflag)
210 			sflag = 1;	/* if -l not explicit, force -s */
211 		loginlist();
212 		if (entries == 0)
213 			(void)printf("No one logged on.\n");
214 	} else {
215 		userlist(argc, argv);
216 		/*
217 		 * Assign explicit "large" format if names given and -s not
218 		 * explicitly stated.  Force the -l AFTER we get names so any
219 		 * remote finger attempts specified won't be mishandled.
220 		 */
221 		if (!sflag)
222 			lflag = 1;	/* if -s not explicit, force -l */
223 	}
224 	if (entries) {
225 		if (lflag)
226 			lflag_print();
227 		else
228 			sflag_print();
229 	}
230 	return (0);
231 }
232 
233 static void
234 loginlist(void)
235 {
236 	PERSON *pn;
237 	DBT data, key;
238 	struct passwd *pw;
239 	struct utmp user;
240 	int r, sflag1;
241 	char name[UT_NAMESIZE + 1];
242 
243 	if (kflag)
244 		errx(1, "can't list logins without reading utmp");
245 
246 	if (!freopen(_PATH_UTMP, "r", stdin))
247 		err(1, "%s", _PATH_UTMP);
248 	name[UT_NAMESIZE] = '\0';
249 	while (fread((char *)&user, sizeof(user), 1, stdin) == 1) {
250 		if (!user.ut_name[0])
251 			continue;
252 		if ((pn = find_person(user.ut_name)) == NULL) {
253 			bcopy(user.ut_name, name, UT_NAMESIZE);
254 			if ((pw = getpwnam(name)) == NULL)
255 				continue;
256 			if (hide(pw))
257 				continue;
258 			pn = enter_person(pw);
259 		}
260 		enter_where(&user, pn);
261 	}
262 	if (db && lflag)
263 		for (sflag1 = R_FIRST;; sflag1 = R_NEXT) {
264 			PERSON *tmp;
265 
266 			r = (*db->seq)(db, &key, &data, sflag1);
267 			if (r == -1)
268 				err(1, "db seq");
269 			if (r == 1)
270 				break;
271 			memmove(&tmp, data.data, sizeof tmp);
272 			enter_lastlog(tmp);
273 		}
274 }
275 
276 static void
277 userlist(int argc, char **argv)
278 {
279 	PERSON *pn;
280 	DBT data, key;
281 	struct utmp user;
282 	struct passwd *pw;
283 	int r, sflag1, *used, *ip;
284 	char **ap, **nargv, **np, **p;
285 	FILE *conf_fp;
286 	char conf_alias[LINE_MAX];
287 	char *conf_realname;
288 	int conf_length;
289 
290 	if ((nargv = malloc((argc+1) * sizeof(char *))) == NULL ||
291 	    (used = calloc(argc, sizeof(int))) == NULL)
292 		err(1, NULL);
293 
294 	/* Pull out all network requests. */
295 	for (ap = p = argv, np = nargv; *p; ++p)
296 		if (index(*p, '@'))
297 			*np++ = *p;
298 		else
299 			*ap++ = *p;
300 
301 	*np++ = NULL;
302 	*ap++ = NULL;
303 
304 	if (!*argv)
305 		goto net;
306 
307 	/*
308 	 * Mark any arguments beginning with '/' as invalid so that we
309 	 * don't accidently confuse them with expansions from finger.conf
310 	 */
311 	for (p = argv, ip = used; *p; ++p, ++ip)
312 	    if (**p == '/') {
313 		*ip = 1;
314 		warnx("%s: no such user", *p);
315 	    }
316 
317 	/*
318 	 * Traverse the finger alias configuration file of the form
319 	 * alias:(user|alias), ignoring comment lines beginning '#'.
320 	 */
321 	if ((conf_fp = fopen(_PATH_FINGERCONF, "r")) != NULL) {
322 	    while(fgets(conf_alias, sizeof(conf_alias), conf_fp) != NULL) {
323 		conf_length = strlen(conf_alias);
324 		if (*conf_alias == '#' || conf_alias[--conf_length] != '\n')
325 		    continue;
326 		conf_alias[conf_length] = '\0';      /* Remove trailing LF */
327 		if ((conf_realname = strchr(conf_alias, ':')) == NULL)
328 		    continue;
329 		*conf_realname = '\0';               /* Replace : with NUL */
330 		for (p = argv; *p; ++p) {
331 		    if (strcmp(*p, conf_alias) == 0) {
332 			if ((*p = strdup(conf_realname+1)) == NULL) {
333 			    err(1, NULL);
334 			}
335 		    }
336 		}
337 	    }
338 	    (void)fclose(conf_fp);
339 	}
340 
341 	/*
342 	 * Traverse the list of possible login names and check the login name
343 	 * and real name against the name specified by the user. If the name
344 	 * begins with a '/', try to read the file of that name instead of
345 	 * gathering the traditional finger information.
346 	 */
347 	if (mflag)
348 		for (p = argv, ip = used; *p; ++p, ++ip) {
349 			if (**p != '/' || *ip == 1 || !show_text("", *p, "")) {
350 				if (((pw = getpwnam(*p)) != NULL) && !hide(pw))
351 					enter_person(pw);
352 				else if (!*ip)
353 					warnx("%s: no such user", *p);
354 			}
355 		}
356 	else {
357 		while ((pw = getpwent()) != NULL) {
358 			for (p = argv, ip = used; *p; ++p, ++ip)
359 				if (**p == '/' && *ip != 1
360 				    && show_text("", *p, ""))
361 					*ip = 1;
362 				else if (match(pw, *p) && !hide(pw)) {
363 					enter_person(pw);
364 					*ip = 1;
365 				}
366 		}
367 		for (p = argv, ip = used; *p; ++p, ++ip)
368 			if (!*ip)
369 				warnx("%s: no such user", *p);
370 	}
371 
372 	/* Handle network requests. */
373 net:	for (p = nargv; *p;) {
374 		netfinger(*p++);
375 		if (*p || entries)
376 		    printf("\n");
377 	}
378 
379 	if (entries == 0)
380 		return;
381 
382 	if (kflag)
383 		return;
384 
385 	/*
386 	 * Scan thru the list of users currently logged in, saving
387 	 * appropriate data whenever a match occurs.
388 	 */
389 	if (!freopen(_PATH_UTMP, "r", stdin))
390 		err(1, "%s", _PATH_UTMP);
391 	while (fread((char *)&user, sizeof(user), 1, stdin) == 1) {
392 		if (!user.ut_name[0])
393 			continue;
394 		if ((pn = find_person(user.ut_name)) == NULL)
395 			continue;
396 		enter_where(&user, pn);
397 	}
398 	if (db)
399 		for (sflag1 = R_FIRST;; sflag1 = R_NEXT) {
400 			PERSON *tmp;
401 
402 			r = (*db->seq)(db, &key, &data, sflag1);
403 			if (r == -1)
404 				err(1, "db seq");
405 			if (r == 1)
406 				break;
407 			memmove(&tmp, data.data, sizeof tmp);
408 			enter_lastlog(tmp);
409 		}
410 }
411