finger.c revision 331722 
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 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Luke Mewburn <lm@rmit.edu.au> added the following on 940622:
35 *    - mail status ("No Mail", "Mail read:...", or "New Mail ...,
36 *	Unread since ...".)
37 *    - 4 digit phone extensions (3210 is printed as x3210.)
38 *    - host/office toggling in short format with -h & -o.
39 *    - short day names (`Tue' printed instead of `Jun 21' if the
40 *	login time is < 6 days.
41 */
42
43#ifndef lint
44static const char copyright[] =
45"@(#) Copyright (c) 1989, 1993\n\
46	The Regents of the University of California.  All rights reserved.\n";
47#endif /* not lint */
48
49#if 0
50#ifndef lint
51static char sccsid[] = "@(#)finger.c	8.5 (Berkeley) 5/4/95";
52#endif
53#endif
54
55#include <sys/cdefs.h>
56__FBSDID("$FreeBSD: stable/11/usr.bin/finger/finger.c 331722 2018-03-29 02:50:57Z eadler $");
57
58/*
59 * Finger prints out information about users.  It is not portable since
60 * certain fields (e.g. the full user name, office, and phone numbers) are
61 * extracted from the gecos field of the passwd file which other UNIXes
62 * may not have or may use for other things.
63 *
64 * There are currently two output formats; the short format is one line
65 * per user and displays login name, tty, login time, real name, idle time,
66 * and either remote host information (default) or office location/phone
67 * number, depending on if -h or -o is used respectively.
68 * The long format gives the same information (in a more legible format) as
69 * well as home directory, shell, mail info, and .plan/.project files.
70 */
71
72#include <sys/types.h>
73#include <sys/socket.h>
74#include <db.h>
75#include <err.h>
76#include <pwd.h>
77#include <stdio.h>
78#include <stdlib.h>
79#include <string.h>
80#include <time.h>
81#include <unistd.h>
82#include <utmpx.h>
83#include <locale.h>
84
85#include "finger.h"
86#include "pathnames.h"
87
88DB *db;
89time_t now;
90static int kflag, mflag, sflag;
91int entries, gflag, lflag, pplan, oflag;
92sa_family_t family = PF_UNSPEC;
93int d_first = -1;
94char tbuf[1024];
95int invoker_root = 0;
96
97static void loginlist(void);
98static int option(int, char **);
99static void usage(void);
100static void userlist(int, char **);
101
102static int
103option(int argc, char **argv)
104{
105	int ch;
106
107	optind = 1;		/* reset getopt */
108
109	while ((ch = getopt(argc, argv, "46gklmpsho")) != -1)
110		switch(ch) {
111		case '4':
112			family = AF_INET;
113			break;
114		case '6':
115			family = AF_INET6;
116			break;
117		case 'g':
118			gflag = 1;
119			break;
120		case 'k':
121			kflag = 1;		/* keep going without utmp */
122			break;
123		case 'l':
124			lflag = 1;		/* long format */
125			break;
126		case 'm':
127			mflag = 1;		/* force exact match of names */
128			break;
129		case 'p':
130			pplan = 1;		/* don't show .plan/.project */
131			break;
132		case 's':
133			sflag = 1;		/* short format */
134			break;
135		case 'h':
136			oflag = 0;		/* remote host info */
137			break;
138		case 'o':
139			oflag = 1;		/* office info */
140			break;
141		case '?':
142		default:
143			usage();
144		}
145
146	return optind;
147}
148
149static void
150usage(void)
151{
152	(void)fprintf(stderr,
153	    "usage: finger [-46gklmpsho] [user ...] [user@host ...]\n");
154	exit(1);
155}
156
157int
158main(int argc, char **argv)
159{
160	int envargc, argcnt;
161	char *envargv[3];
162	struct passwd *pw;
163	static char myname[] = "finger";
164
165	if (getuid() == 0 || geteuid() == 0) {
166		invoker_root = 1;
167		if ((pw = getpwnam(UNPRIV_NAME)) && pw->pw_uid > 0) {
168			if (setgid(pw->pw_gid) != 0)
169				err(1, "setgid()");
170			if (setuid(pw->pw_uid) != 0)
171				err(1, "setuid()");
172		} else {
173			if (setgid(UNPRIV_UGID) != 0)
174				err(1, "setgid()");
175			if (setuid(UNPRIV_UGID) != 0)
176				err(1, "setuid()");
177		}
178	}
179
180	(void) setlocale(LC_ALL, "");
181
182				/* remove this line to get remote host */
183	oflag = 1;		/* default to old "office" behavior */
184
185	/*
186	 * Process environment variables followed by command line arguments.
187	 */
188	if ((envargv[1] = getenv("FINGER"))) {
189		envargc = 2;
190		envargv[0] = myname;
191		envargv[2] = NULL;
192		(void) option(envargc, envargv);
193	}
194
195	argcnt = option(argc, argv);
196	argc -= argcnt;
197	argv += argcnt;
198
199	(void)time(&now);
200	setpassent(1);
201	if (!*argv) {
202		/*
203		 * Assign explicit "small" format if no names given and -l
204		 * not selected.  Force the -s BEFORE we get names so proper
205		 * screening will be done.
206		 */
207		if (!lflag)
208			sflag = 1;	/* if -l not explicit, force -s */
209		loginlist();
210		if (entries == 0)
211			(void)printf("No one logged on.\n");
212	} else {
213		userlist(argc, argv);
214		/*
215		 * Assign explicit "large" format if names given and -s not
216		 * explicitly stated.  Force the -l AFTER we get names so any
217		 * remote finger attempts specified won't be mishandled.
218		 */
219		if (!sflag)
220			lflag = 1;	/* if -s not explicit, force -l */
221	}
222	if (entries) {
223		if (lflag)
224			lflag_print();
225		else
226			sflag_print();
227	}
228	return (0);
229}
230
231static void
232loginlist(void)
233{
234	PERSON *pn;
235	DBT data, key;
236	struct passwd *pw;
237	struct utmpx *user;
238	int r, sflag1;
239
240	if (kflag)
241		errx(1, "can't list logins without reading utmp");
242
243	setutxent();
244	while ((user = getutxent()) != NULL) {
245		if (user->ut_type != USER_PROCESS)
246			continue;
247		if ((pn = find_person(user->ut_user)) == NULL) {
248			if ((pw = getpwnam(user->ut_user)) == NULL)
249				continue;
250			if (hide(pw))
251				continue;
252			pn = enter_person(pw);
253		}
254		enter_where(user, pn);
255	}
256	endutxent();
257	if (db && lflag)
258		for (sflag1 = R_FIRST;; sflag1 = R_NEXT) {
259			PERSON *tmp;
260
261			r = (*db->seq)(db, &key, &data, sflag1);
262			if (r == -1)
263				err(1, "db seq");
264			if (r == 1)
265				break;
266			memmove(&tmp, data.data, sizeof tmp);
267			enter_lastlog(tmp);
268		}
269}
270
271static void
272userlist(int argc, char **argv)
273{
274	PERSON *pn;
275	DBT data, key;
276	struct utmpx *user;
277	struct passwd *pw;
278	int r, sflag1, *used, *ip;
279	char **ap, **nargv, **np, **p;
280	FILE *conf_fp;
281	char conf_alias[LINE_MAX];
282	char *conf_realname;
283	int conf_length;
284
285	if ((nargv = malloc((argc+1) * sizeof(char *))) == NULL ||
286	    (used = calloc(argc, sizeof(int))) == NULL)
287		err(1, NULL);
288
289	/* Pull out all network requests. */
290	for (ap = p = argv, np = nargv; *p; ++p)
291		if (strchr(*p, '@'))
292			*np++ = *p;
293		else
294			*ap++ = *p;
295
296	*np++ = NULL;
297	*ap++ = NULL;
298
299	if (!*argv)
300		goto net;
301
302	/*
303	 * Mark any arguments beginning with '/' as invalid so that we
304	 * don't accidentally confuse them with expansions from finger.conf
305	 */
306	for (p = argv, ip = used; *p; ++p, ++ip)
307	    if (**p == '/') {
308		*ip = 1;
309		warnx("%s: no such user", *p);
310	    }
311
312	/*
313	 * Traverse the finger alias configuration file of the form
314	 * alias:(user|alias), ignoring comment lines beginning '#'.
315	 */
316	if ((conf_fp = fopen(_PATH_FINGERCONF, "r")) != NULL) {
317	    while(fgets(conf_alias, sizeof(conf_alias), conf_fp) != NULL) {
318		conf_length = strlen(conf_alias);
319		if (*conf_alias == '#' || conf_alias[--conf_length] != '\n')
320		    continue;
321		conf_alias[conf_length] = '\0';      /* Remove trailing LF */
322		if ((conf_realname = strchr(conf_alias, ':')) == NULL)
323		    continue;
324		*conf_realname = '\0';               /* Replace : with NUL */
325		for (p = argv; *p; ++p) {
326		    if (strcmp(*p, conf_alias) == 0) {
327			if ((*p = strdup(conf_realname+1)) == NULL) {
328			    err(1, NULL);
329			}
330		    }
331		}
332	    }
333	    (void)fclose(conf_fp);
334	}
335
336	/*
337	 * Traverse the list of possible login names and check the login name
338	 * and real name against the name specified by the user. If the name
339	 * begins with a '/', try to read the file of that name instead of
340	 * gathering the traditional finger information.
341	 */
342	if (mflag)
343		for (p = argv, ip = used; *p; ++p, ++ip) {
344			if (**p != '/' || *ip == 1 || !show_text("", *p, "")) {
345				if (((pw = getpwnam(*p)) != NULL) && !hide(pw))
346					enter_person(pw);
347				else if (!*ip)
348					warnx("%s: no such user", *p);
349			}
350		}
351	else {
352		while ((pw = getpwent()) != NULL) {
353			for (p = argv, ip = used; *p; ++p, ++ip)
354				if (**p == '/' && *ip != 1
355				    && show_text("", *p, ""))
356					*ip = 1;
357				else if (match(pw, *p) && !hide(pw)) {
358					enter_person(pw);
359					*ip = 1;
360				}
361		}
362		for (p = argv, ip = used; *p; ++p, ++ip)
363			if (!*ip)
364				warnx("%s: no such user", *p);
365	}
366
367	/* Handle network requests. */
368net:	for (p = nargv; *p;) {
369		netfinger(*p++);
370		if (*p || entries)
371		    printf("\n");
372	}
373
374	free(used);
375	if (entries == 0)
376		return;
377
378	if (kflag)
379		return;
380
381	/*
382	 * Scan thru the list of users currently logged in, saving
383	 * appropriate data whenever a match occurs.
384	 */
385	setutxent();
386	while ((user = getutxent()) != NULL) {
387		if (user->ut_type != USER_PROCESS)
388			continue;
389		if ((pn = find_person(user->ut_user)) == NULL)
390			continue;
391		enter_where(user, pn);
392	}
393	endutxent();
394	if (db)
395		for (sflag1 = R_FIRST;; sflag1 = R_NEXT) {
396			PERSON *tmp;
397
398			r = (*db->seq)(db, &key, &data, sflag1);
399			if (r == -1)
400				err(1, "db seq");
401			if (r == 1)
402				break;
403			memmove(&tmp, data.data, sizeof tmp);
404			enter_lastlog(tmp);
405		}
406}
407