xref: /openbsd/usr.bin/finger/util.c (revision 8529ddd3)
1 /*	$OpenBSD: util.c,v 1.30 2015/01/16 06:40:07 deraadt Exp $	*/
2 
3 /*
4  * Copyright (c) 1989 The Regents of the University of California.
5  * All rights reserved.
6  * Portions Copyright (c) 1983, 1995, 1996 Eric P. Allman (woof!)
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/uio.h>
38 #include <sys/stat.h>
39 #include <err.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <ctype.h>
43 #include <string.h>
44 #include <paths.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <unistd.h>
48 #include <vis.h>
49 #include "finger.h"
50 #include "extern.h"
51 
52 char	*estrdup(char *);
53 WHERE	*walloc(PERSON *pn);
54 void	find_idle_and_ttywrite(WHERE *);
55 void	userinfo(PERSON *, struct passwd *);
56 
57 void
58 find_idle_and_ttywrite(WHERE *w)
59 {
60 	struct stat sb;
61 
62 	(void)snprintf(tbuf, sizeof(tbuf), "%s%s", _PATH_DEV, w->tty);
63 	if (stat(tbuf, &sb) < 0) {
64 		/* Don't bitch about it, just handle it... */
65 		w->idletime = 0;
66 		w->writable = 0;
67 
68 		return;
69 	}
70 	w->idletime = now < sb.st_atime ? 0 : now - sb.st_atime;
71 
72 #define	TALKABLE	0220		/* tty is writable if 220 mode */
73 	w->writable = ((sb.st_mode & TALKABLE) == TALKABLE);
74 }
75 
76 char *
77 estrdup(char *s)
78 {
79 	char *p = strdup(s);
80 	if (!p)
81 		err(1, "strdup");
82 	return (p);
83 }
84 
85 void
86 userinfo(PERSON *pn, struct passwd *pw)
87 {
88 	char *p;
89 	char *bp, name[1024];
90 	struct stat sb;
91 	int len;
92 
93 	pn->realname = pn->office = pn->officephone = pn->homephone = NULL;
94 	pn->mailrecv = -1;		/* -1 == not_valid */
95 
96 	pn->uid = pw->pw_uid;
97 	pn->name = estrdup(pw->pw_name);
98 	pn->dir = estrdup(pw->pw_dir);
99 	pn->shell = estrdup(pw->pw_shell);
100 
101 	(void)strlcpy(bp = tbuf, pw->pw_gecos, sizeof(tbuf));
102 
103 	/* ampersands get replaced by the login name */
104 	if (!(p = strsep(&bp, ",")))
105 		return;
106 	expandusername(p, pw->pw_name, name, sizeof(name));
107 	if (stravis(&pn->realname, p, VIS_SAFE|VIS_NOSLASH) == -1)
108 		err(1, "stravis");
109 	if ((p = strsep(&bp, ",")) && *p) {
110 		if (stravis(&pn->office, p, VIS_SAFE|VIS_NOSLASH) == -1)
111 			err(1, "stravis");
112 	}
113 	if ((p = strsep(&bp, ",")) && *p) {
114 		if (stravis(&pn->officephone, p, VIS_SAFE|VIS_NOSLASH) == -1)
115 			err(1, "stravis");
116 	}
117 	if ((p = strsep(&bp, ",")) && *p) {
118 		if (stravis(&pn->homephone, p, VIS_SAFE|VIS_NOSLASH) == -1)
119 			err(1, "stravis");
120 	}
121 	len = snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_MAILSPOOL,
122 	    pw->pw_name);
123 	if (len != -1 && len < sizeof(tbuf)) {
124 		if (stat(tbuf, &sb) < 0) {
125 			if (errno != ENOENT) {
126 				warn("%s", tbuf);
127 				return;
128 			}
129 		} else if (sb.st_size != 0) {
130 			pn->mailrecv = sb.st_mtime;
131 			pn->mailread = sb.st_atime;
132 		}
133 	}
134 }
135 
136 int
137 match(struct passwd *pw, char *user)
138 {
139 	char *p, *t;
140 	char name[1024];
141 
142 	(void)strlcpy(p = tbuf, pw->pw_gecos, sizeof(tbuf));
143 
144 	/* ampersands get replaced by the login name */
145 	if (!(p = strtok(p, ",")))
146 		return (0);
147 	expandusername(p, pw->pw_name, name, sizeof(name));
148 	for (t = name; (p = strtok(t, "\t ")) != NULL; t = NULL)
149 		if (!strcasecmp(p, user))
150 			return (1);
151 	return (0);
152 }
153 
154 /* inspired by usr.sbin/sendmail/util.c::buildfname */
155 void
156 expandusername(char *gecos, char *login, char *buf, int buflen)
157 {
158 	char *p, *bp;
159 
160 	/* why do we skip asterisks!?!? */
161 	if (*gecos == '*')
162 		gecos++;
163 	bp = buf;
164 
165 	/* copy gecos, interpolating & to be full name */
166 	for (p = gecos; *p != '\0'; p++) {
167 		if (bp >= &buf[buflen - 1]) {
168 			/* buffer overflow - just use login name */
169 			strlcpy(buf, login, buflen);
170 			buf[buflen - 1] = '\0';
171 			return;
172 		}
173 		if (*p == '&') {
174 			/* interpolate full name */
175 			strlcpy(bp, login, buflen - (bp - buf));
176 			*bp = toupper((unsigned char)*bp);
177 			bp += strlen(bp);
178 		}
179 		else
180 			*bp++ = *p;
181 	}
182 	*bp = '\0';
183 }
184 
185 void
186 enter_lastlog(PERSON *pn)
187 {
188 	WHERE *w;
189 	static int opened, fd;
190 	struct lastlog ll;
191 	char doit = 0;
192 
193 	/* some systems may not maintain lastlog, don't report errors. */
194 	if (!opened) {
195 		fd = open(_PATH_LASTLOG, O_RDONLY);
196 		opened = 1;
197 	}
198 	if (fd == -1 ||
199 	    lseek(fd, (off_t)(pn->uid * sizeof(ll)), SEEK_SET) !=
200 	    (long)(pn->uid * sizeof(ll)) ||
201 	    read(fd, (char *)&ll, sizeof(ll)) != sizeof(ll)) {
202 			/* as if never logged in */
203 			ll.ll_line[0] = ll.ll_host[0] = '\0';
204 			ll.ll_time = 0;
205 		}
206 	if ((w = pn->whead) == NULL)
207 		doit = 1;
208 	else if (ll.ll_time != 0) {
209 		/* if last login is earlier than some current login */
210 		for (; !doit && w != NULL; w = w->next)
211 			if (w->info == LOGGEDIN && w->loginat < ll.ll_time)
212 				doit = 1;
213 		/*
214 		 * and if it's not any of the current logins
215 		 * can't use time comparison because there may be a small
216 		 * discrepency since login calls time() twice
217 		 */
218 		for (w = pn->whead; doit && w != NULL; w = w->next)
219 			if (w->info == LOGGEDIN &&
220 			    strncmp(w->tty, ll.ll_line, UT_LINESIZE) == 0)
221 				doit = 0;
222 	}
223 	if (doit) {
224 		w = walloc(pn);
225 		w->info = LASTLOG;
226 		bcopy(ll.ll_line, w->tty, UT_LINESIZE);
227 		w->tty[UT_LINESIZE] = 0;
228 		bcopy(ll.ll_host, w->host, UT_HOSTSIZE);
229 		w->host[UT_HOSTSIZE] = 0;
230 		w->loginat = ll.ll_time;
231 	}
232 }
233 
234 void
235 enter_where(struct utmp *ut, PERSON *pn)
236 {
237 	WHERE *w = walloc(pn);
238 
239 	w->info = LOGGEDIN;
240 	bcopy(ut->ut_line, w->tty, UT_LINESIZE);
241 	w->tty[UT_LINESIZE] = 0;
242 	bcopy(ut->ut_host, w->host, UT_HOSTSIZE);
243 	w->host[UT_HOSTSIZE] = 0;
244 	w->loginat = (time_t)ut->ut_time;
245 	find_idle_and_ttywrite(w);
246 }
247 
248 PERSON *
249 enter_person(struct passwd *pw)
250 {
251 	PERSON *pn, **pp;
252 
253 	for (pp = htab + hash(pw->pw_name);
254 	    *pp != NULL && strcmp((*pp)->name, pw->pw_name) != 0;
255 	    pp = &(*pp)->hlink)
256 		;
257 	if ((pn = *pp) == NULL) {
258 		pn = palloc();
259 		entries++;
260 		if (phead == NULL)
261 			phead = ptail = pn;
262 		else {
263 			ptail->next = pn;
264 			ptail = pn;
265 		}
266 		pn->next = NULL;
267 		pn->hlink = NULL;
268 		*pp = pn;
269 		userinfo(pn, pw);
270 		pn->whead = NULL;
271 	}
272 	return (pn);
273 }
274 
275 PERSON *
276 find_person(char *name)
277 {
278 	PERSON *pn;
279 
280 	/* name may be only UT_NAMESIZE long and not terminated */
281 	for (pn = htab[hash(name)];
282 	    pn != NULL && strncmp(pn->name, name, UT_NAMESIZE) != 0;
283 	    pn = pn->hlink)
284 		;
285 	return (pn);
286 }
287 
288 int
289 hash(char *name)
290 {
291 	int h, i;
292 
293 	h = 0;
294 	/* name may be only UT_NAMESIZE long and not terminated */
295 	for (i = UT_NAMESIZE; --i >= 0 && *name;)
296 		h = ((h << 2 | h >> (HBITS - 2)) ^ *name++) & HMASK;
297 	return (h);
298 }
299 
300 PERSON *
301 palloc(void)
302 {
303 	PERSON *p;
304 
305 	if ((p = (PERSON *)malloc((u_int) sizeof(PERSON))) == NULL)
306 		err(1, "malloc");
307 	return (p);
308 }
309 
310 WHERE *
311 walloc(PERSON *pn)
312 {
313 	WHERE *w;
314 
315 	if ((w = (WHERE *)malloc((u_int) sizeof(WHERE))) == NULL)
316 		err(1, "malloc");
317 	if (pn->whead == NULL)
318 		pn->whead = pn->wtail = w;
319 	else {
320 		pn->wtail->next = w;
321 		pn->wtail = w;
322 	}
323 	w->next = NULL;
324 	return (w);
325 }
326 
327 char *
328 prphone(char *num)
329 {
330 	char *p;
331 	int len;
332 	static char pbuf[15];
333 
334 	/* don't touch anything if the user has their own formatting */
335 	for (p = num; *p; ++p)
336 		if (!isdigit((unsigned char)*p))
337 			return (num);
338 	len = p - num;
339 	p = pbuf;
340 	switch (len) {
341 	case 11:			/* +0-123-456-7890 */
342 		*p++ = '+';
343 		*p++ = *num++;
344 		*p++ = '-';
345 		/* FALLTHROUGH */
346 	case 10:			/* 012-345-6789 */
347 		*p++ = *num++;
348 		*p++ = *num++;
349 		*p++ = *num++;
350 		*p++ = '-';
351 		/* FALLTHROUGH */
352 	case 7:				/* 012-3456 */
353 		*p++ = *num++;
354 		*p++ = *num++;
355 		*p++ = *num++;
356 		break;
357 	case 5:				/* x0-1234 */
358 	case 4:				/* x1234 */
359 		*p++ = 'x';
360 		*p++ = *num++;
361 		break;
362 	default:
363 		return (num);
364 	}
365 	if (len != 4) {
366 		*p++ = '-';
367 		*p++ = *num++;
368 	}
369 	*p++ = *num++;
370 	*p++ = *num++;
371 	*p++ = *num++;
372 	*p = '\0';
373 	return (pbuf);
374 }
375