xref: /freebsd/usr.bin/finger/util.c (revision 1da7f3f6f72b2245e458fc7195733268ae4a1136)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/socket.h>
37 #include <sys/stat.h>
38 #include <ctype.h>
39 #include <db.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <paths.h>
44 #include <pwd.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <utmpx.h>
50 #include "finger.h"
51 #include "pathnames.h"
52 
53 static void	 find_idle_and_ttywrite(WHERE *);
54 static void	 userinfo(PERSON *, struct passwd *);
55 static WHERE	*walloc(PERSON *);
56 
57 int
58 match(struct passwd *pw, const char *user)
59 {
60 	char *p, *t;
61 	char name[1024];
62 
63 	if (!strcasecmp(pw->pw_name, user))
64 		return(1);
65 
66 	/*
67 	 * XXX
68 	 * Why do we skip asterisks!?!?
69 	 */
70 	(void)strncpy(p = tbuf, pw->pw_gecos, sizeof(tbuf));
71 	tbuf[sizeof(tbuf) - 1] = '\0';
72 	if (*p == '*')
73 		++p;
74 
75 	/* Ampersands get replaced by the login name. */
76 	if ((p = strtok(p, ",")) == NULL)
77 		return(0);
78 
79 	for (t = name; t < &name[sizeof(name) - 1] && (*t = *p) != '\0'; ++p) {
80 		if (*t == '&') {
81 			(void)strncpy(t, pw->pw_name,
82 			    sizeof(name) - (t - name));
83 			name[sizeof(name) - 1] = '\0';
84 			while (t < &name[sizeof(name) - 1] && *++t)
85 				continue;
86 		} else {
87 			++t;
88 		}
89 	}
90 	*t = '\0';
91 	for (t = name; (p = strtok(t, "\t ")) != NULL; t = NULL)
92 		if (!strcasecmp(p, user))
93 			return(1);
94 	return(0);
95 }
96 
97 void
98 enter_lastlog(PERSON *pn)
99 {
100 	WHERE *w;
101 	struct utmpx *ut = NULL;
102 	char doit = 0;
103 
104 	if (setutxdb(UTXDB_LASTLOGIN, NULL) == 0)
105 		ut = getutxuser(pn->name);
106 	if ((w = pn->whead) == NULL)
107 		doit = 1;
108 	else if (ut != NULL && ut->ut_type == USER_PROCESS) {
109 		/* if last login is earlier than some current login */
110 		for (; !doit && w != NULL; w = w->next)
111 			if (w->info == LOGGEDIN &&
112 			    w->loginat < ut->ut_tv.tv_sec)
113 				doit = 1;
114 		/*
115 		 * and if it's not any of the current logins
116 		 * can't use time comparison because there may be a small
117 		 * discrepancy since login calls time() twice
118 		 */
119 		for (w = pn->whead; doit && w != NULL; w = w->next)
120 			if (w->info == LOGGEDIN &&
121 			    strcmp(w->tty, ut->ut_line) == 0)
122 				doit = 0;
123 	}
124 	if (ut != NULL && doit) {
125 		w = walloc(pn);
126 		w->info = LASTLOG;
127 		strcpy(w->tty, ut->ut_line);
128 		strcpy(w->host, ut->ut_host);
129 		w->loginat = ut->ut_tv.tv_sec;
130 	}
131 	endutxent();
132 }
133 
134 void
135 enter_where(struct utmpx *ut, PERSON *pn)
136 {
137 	WHERE *w;
138 
139 	w = walloc(pn);
140 	w->info = LOGGEDIN;
141 	strcpy(w->tty, ut->ut_line);
142 	strcpy(w->host, ut->ut_host);
143 	w->loginat = ut->ut_tv.tv_sec;
144 	find_idle_and_ttywrite(w);
145 }
146 
147 PERSON *
148 enter_person(struct passwd *pw)
149 {
150 	DBT data, key;
151 	PERSON *pn;
152 
153 	if (db == NULL &&
154 	    (db = dbopen(NULL, O_RDWR, 0, DB_BTREE, NULL)) == NULL)
155 		err(1, NULL);
156 
157 	key.data = pw->pw_name;
158 	key.size = strlen(pw->pw_name);
159 
160 	switch ((*db->get)(db, &key, &data, 0)) {
161 	case 0:
162 		memmove(&pn, data.data, sizeof pn);
163 		return (pn);
164 	default:
165 	case -1:
166 		err(1, "db get");
167 		/* NOTREACHED */
168 	case 1:
169 		++entries;
170 		pn = palloc();
171 		userinfo(pn, pw);
172 		pn->whead = NULL;
173 
174 		data.size = sizeof(PERSON *);
175 		data.data = &pn;
176 		if ((*db->put)(db, &key, &data, 0))
177 			err(1, "db put");
178 		return (pn);
179 	}
180 }
181 
182 PERSON *
183 find_person(char *name)
184 {
185 	struct passwd *pw;
186 
187 	DBT data, key;
188 	PERSON *p;
189 
190 	if (!db)
191 		return(NULL);
192 
193 	if ((pw = getpwnam(name)) && hide(pw))
194 		return(NULL);
195 
196 	key.data = name;
197 	key.size = strlen(name);
198 
199 	if ((*db->get)(db, &key, &data, 0))
200 		return (NULL);
201 	memmove(&p, data.data, sizeof p);
202 	return (p);
203 }
204 
205 PERSON *
206 palloc(void)
207 {
208 	PERSON *p;
209 
210 	if ((p = malloc(sizeof(PERSON))) == NULL)
211 		err(1, NULL);
212 	return(p);
213 }
214 
215 static WHERE *
216 walloc(PERSON *pn)
217 {
218 	WHERE *w;
219 
220 	if ((w = malloc(sizeof(WHERE))) == NULL)
221 		err(1, NULL);
222 	if (pn->whead == NULL)
223 		pn->whead = pn->wtail = w;
224 	else {
225 		pn->wtail->next = w;
226 		pn->wtail = w;
227 	}
228 	w->next = NULL;
229 	return(w);
230 }
231 
232 char *
233 prphone(char *num)
234 {
235 	char *p;
236 	int len;
237 	static char pbuf[20];
238 
239 	/* don't touch anything if the user has their own formatting */
240 	for (p = num; *p; ++p)
241 		if (!isdigit(*p))
242 			return(num);
243 	len = p - num;
244 	p = pbuf;
245 	switch(len) {
246 	case 11:			/* +0-123-456-7890 */
247 		*p++ = '+';
248 		*p++ = *num++;
249 		*p++ = '-';
250 		/* FALLTHROUGH */
251 	case 10:			/* 012-345-6789 */
252 		*p++ = *num++;
253 		*p++ = *num++;
254 		*p++ = *num++;
255 		*p++ = '-';
256 		/* FALLTHROUGH */
257 	case 7:				/* 012-3456 */
258 		*p++ = *num++;
259 		*p++ = *num++;
260 		*p++ = *num++;
261 		break;
262 	case 5:				/* x0-1234 */
263 	case 4:				/* x1234 */
264 		*p++ = 'x';
265 		*p++ = *num++;
266 		break;
267 	default:
268 		return(num);
269 	}
270 	if (len != 4) {
271 	    *p++ = '-';
272 	    *p++ = *num++;
273 	}
274 	*p++ = *num++;
275 	*p++ = *num++;
276 	*p++ = *num++;
277 	*p = '\0';
278 	return(pbuf);
279 }
280 
281 static void
282 find_idle_and_ttywrite(WHERE *w)
283 {
284 	struct stat sb;
285 	time_t touched;
286 	int error;
287 
288 	(void)snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_DEV, w->tty);
289 
290 	error = stat(tbuf, &sb);
291 	if (error < 0 && errno == ENOENT) {
292 		/*
293 		 * The terminal listed is not actually a terminal (i.e.,
294 		 * ":0").  This is a failure, so we'll skip printing
295 		 * out the idle time, which is non-ideal but better
296 		 * than a bogus warning and idle time.
297 		 */
298 		w->idletime = -1;
299 		return;
300 	} else if (error < 0) {
301 		warn("%s", tbuf);
302 		w->idletime = -1;
303 		return;
304 	}
305 	touched = sb.st_atime;
306 	if (touched < w->loginat) {
307 		/* tty untouched since before login */
308 		touched = w->loginat;
309 	}
310 	w->idletime = now < touched ? 0 : now - touched;
311 
312 #define	TALKABLE	0220		/* tty is writable if 220 mode */
313 	w->writable = ((sb.st_mode & TALKABLE) == TALKABLE);
314 }
315 
316 static void
317 userinfo(PERSON *pn, struct passwd *pw)
318 {
319 	char *p, *t;
320 	char *bp, name[1024];
321 	struct stat sb;
322 
323 	pn->realname = pn->office = pn->officephone = pn->homephone = NULL;
324 
325 	pn->uid = pw->pw_uid;
326 	if ((pn->name = strdup(pw->pw_name)) == NULL)
327 		err(1, "strdup failed");
328 	if ((pn->dir = strdup(pw->pw_dir)) == NULL)
329 		err(1, "strdup failed");
330 	if ((pn->shell = strdup(pw->pw_shell)) == NULL)
331 		err(1, "strdup failed");
332 
333 	/* why do we skip asterisks!?!? */
334 	(void)strncpy(bp = tbuf, pw->pw_gecos, sizeof(tbuf));
335 	tbuf[sizeof(tbuf) - 1] = '\0';
336 	if (*bp == '*')
337 		++bp;
338 
339 	/* ampersands get replaced by the login name */
340 	if (!(p = strsep(&bp, ",")))
341 		return;
342 	for (t = name; t < &name[sizeof(name) - 1] && (*t = *p) != '\0'; ++p) {
343 		if (*t == '&') {
344 			(void)strncpy(t, pw->pw_name,
345 			    sizeof(name) - (t - name));
346 			name[sizeof(name) - 1] = '\0';
347 			if (islower(*t))
348 				*t = toupper(*t);
349 			while (t < &name[sizeof(name) - 1] && *++t)
350 				continue;
351 		} else {
352 			++t;
353 		}
354 	}
355 	*t = '\0';
356 	if ((pn->realname = strdup(name)) == NULL)
357 		err(1, "strdup failed");
358 	pn->office = ((p = strsep(&bp, ",")) && *p) ?
359 	    strdup(p) : NULL;
360 	pn->officephone = ((p = strsep(&bp, ",")) && *p) ?
361 	    strdup(p) : NULL;
362 	pn->homephone = ((p = strsep(&bp, ",")) && *p) ?
363 	    strdup(p) : NULL;
364 	(void)snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_MAILDIR, pw->pw_name);
365 	pn->mailrecv = -1;		/* -1 == not_valid */
366 	if (stat(tbuf, &sb) < 0) {
367 		if (errno != ENOENT) {
368 			warn("%s", tbuf);
369 			return;
370 		}
371 	} else if (sb.st_size != 0) {
372 		pn->mailrecv = sb.st_mtime;
373 		pn->mailread = sb.st_atime;
374 	}
375 }
376 
377 /*
378  * Is this user hiding from finger?
379  * If ~<user>/.nofinger exists, return 1 (hide), else return 0 (nohide).
380  * Nobody can hide from root.
381  */
382 
383 int
384 hide(struct passwd *pw)
385 {
386 	struct stat st;
387 	char buf[MAXPATHLEN];
388 
389 	if (invoker_root || !pw->pw_dir)
390 		return 0;
391 
392 	snprintf(buf, sizeof(buf), "%s/%s", pw->pw_dir, _PATH_NOFINGER);
393 
394 	if (stat(buf, &st) == 0)
395 		return 1;
396 
397 	return 0;
398 }
399