1/*	$NetBSD: common.c,v 1.8 2015/10/28 07:27:24 shm Exp $	*/
2
3/*-
4 * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31#include <sys/cdefs.h>
32__RCSID("$NetBSD: common.c,v 1.8 2015/10/28 07:27:24 shm Exp $");
33
34#include <sys/types.h>
35#include <sys/param.h>
36#include <sys/socket.h>
37#include <stdio.h>
38#include <string.h>
39#include <unistd.h>
40#include <stdlib.h>
41#include <syslog.h>
42#include <fcntl.h>
43#include <ttyent.h>
44#include <setjmp.h>
45#include <time.h>
46#include <pwd.h>
47#include <err.h>
48#include <vis.h>
49#include <util.h>
50
51#include "pathnames.h"
52#include "common.h"
53
54#if defined(KERBEROS5)
55#define	NBUFSIZ		(MAXLOGNAME + 1 + 5)	/* .root suffix */
56#else
57#define	NBUFSIZ		(MAXLOGNAME + 1)
58#endif
59
60#ifdef SUPPORT_UTMP
61#include <utmp.h>
62static void	 doutmp(void);
63static void	 dolastlog(int);
64#endif
65#ifdef SUPPORT_UTMPX
66#include <utmpx.h>
67static void	 doutmpx(void);
68static void	 dolastlogx(int);
69#endif
70
71/*
72 * This bounds the time given to login.  Not a define so it can
73 * be patched on machines where it's too small.
74 */
75u_int	timeout = 300;
76
77void	 decode_ss(const char *);
78struct	passwd *pwd;
79int	failures, have_ss;
80char	term[64], *envinit[1], *hostname, *tty, *nested;
81const char *username;
82struct timeval now;
83struct sockaddr_storage ss;
84
85char *
86trimloginname(char *u)
87{
88	if (strlen(u) > MAXLOGNAME)
89		u[MAXLOGNAME] = '\0';
90	return u;
91}
92
93char *
94getloginname(void)
95{
96	int ch;
97	char *p;
98	static char nbuf[NBUFSIZ];
99
100	for (;;) {
101		(void)printf("login: ");
102		for (p = nbuf; (ch = getchar()) != '\n'; ) {
103			if (ch == EOF) {
104				badlogin(username);
105				exit(EXIT_FAILURE);
106			}
107			if (p < nbuf + (NBUFSIZ - 1))
108				*p++ = ch;
109		}
110		if (p > nbuf) {
111			if (nbuf[0] == '-')
112				(void)fprintf(stderr,
113				    "login names may not start with '-'.\n");
114			else {
115				*p = '\0';
116				return nbuf;
117			}
118		}
119	}
120}
121
122int
123rootterm(char *ttyn)
124{
125	struct ttyent *t;
126
127	return ((t = getttynam(ttyn)) && t->ty_status & TTY_SECURE);
128}
129
130static jmp_buf motdinterrupt;
131
132void
133motd(const char *fname)
134{
135	int fd, nchars;
136	sig_t oldint;
137	char tbuf[8192];
138
139	if ((fd = open(fname ? fname : _PATH_MOTDFILE, O_RDONLY, 0)) < 0)
140		return;
141	oldint = signal(SIGINT, sigint);
142	if (setjmp(motdinterrupt) == 0)
143		while ((nchars = read(fd, tbuf, sizeof(tbuf))) > 0)
144			(void)write(fileno(stdout), tbuf, nchars);
145	(void)signal(SIGINT, oldint);
146	(void)close(fd);
147}
148
149/* ARGSUSED */
150void __dead
151sigint(int signo)
152{
153
154	longjmp(motdinterrupt, 1);
155}
156
157/* ARGSUSED */
158void __dead
159timedout(int signo)
160{
161
162	(void)fprintf(stderr, "Login timed out after %d seconds\n", timeout);
163	exit(EXIT_FAILURE);
164}
165
166void
167update_db(int quietlog, int rootlogin, int fflag)
168{
169	struct sockaddr_storage ass;
170	char assbuf[1024];
171	socklen_t alen;
172	const char *hname;
173	int remote;
174
175	hname = (hostname == NULL) ? "?" : hostname;
176	alen = sizeof(ass);
177	if (getpeername(STDIN_FILENO, (struct sockaddr *)&ass, &alen) != -1) {
178		(void)sockaddr_snprintf(assbuf,
179		    sizeof(assbuf), "%A (%a)", (void *)&ass);
180		if (have_ss) {
181			char ssbuf[1024];
182			(void)sockaddr_snprintf(ssbuf,
183			    sizeof(ssbuf), "%A(%a)", (void *)&ss);
184			 if (memcmp(&ass, &ss, alen) != 0)
185				syslog(LOG_NOTICE,
186				    "login %s on tty %s address mismatch "
187				    "passed %s != actual %s", username, tty,
188				    ssbuf, assbuf);
189		} else
190			ss = ass;
191		remote = 1;
192	} else if (have_ss) {
193		(void)sockaddr_snprintf(assbuf,
194		    sizeof(assbuf), "%A(%a)", (void *)&ss);
195		remote = 1;
196	} else if (hostname) {
197		(void)snprintf(assbuf, sizeof(assbuf), "? ?");
198		remote = 1;
199	} else
200		remote = 0;
201
202	/* If fflag is on, assume caller/authenticator has logged root login. */
203	if (rootlogin && fflag == 0) {
204		if (remote)
205			syslog(LOG_NOTICE, "ROOT LOGIN (%s) on tty %s from %s /"
206			    " %s", username, tty, hname, assbuf);
207		else
208			syslog(LOG_NOTICE, "ROOT LOGIN (%s) on tty %s",
209			    username, tty);
210	} else if (nested != NULL) {
211		if (remote)
212			syslog(LOG_NOTICE, "%s to %s on tty %s from %s / "
213			    "%s", nested, pwd->pw_name, tty, hname, assbuf);
214		else
215			syslog(LOG_NOTICE, "%s to %s on tty %s", nested,
216			    pwd->pw_name, tty);
217	} else {
218		if (remote)
219			syslog(LOG_NOTICE, "%s on tty %s from %s / %s",
220			    pwd->pw_name, tty, hname, assbuf);
221		else
222			syslog(LOG_NOTICE, "%s on tty %s",
223			    pwd->pw_name, tty);
224	}
225	(void)gettimeofday(&now, NULL);
226#ifdef SUPPORT_UTMPX
227	doutmpx();
228	dolastlogx(quietlog);
229	quietlog = 1;
230#endif
231#ifdef SUPPORT_UTMP
232	doutmp();
233	dolastlog(quietlog);
234#endif
235}
236
237#ifdef SUPPORT_UTMPX
238static void
239doutmpx(void)
240{
241	struct utmpx utmpx;
242	char *t;
243
244	memset((void *)&utmpx, 0, sizeof(utmpx));
245	utmpx.ut_tv = now;
246	(void)strncpy(utmpx.ut_name, username, sizeof(utmpx.ut_name));
247	if (hostname) {
248		(void)strncpy(utmpx.ut_host, hostname, sizeof(utmpx.ut_host));
249		utmpx.ut_ss = ss;
250	}
251	(void)strncpy(utmpx.ut_line, tty, sizeof(utmpx.ut_line));
252	utmpx.ut_type = USER_PROCESS;
253	utmpx.ut_pid = getpid();
254	t = tty + strlen(tty);
255	if ((size_t)(t - tty) >= sizeof(utmpx.ut_id)) {
256	    (void)strncpy(utmpx.ut_id, t - sizeof(utmpx.ut_id),
257		sizeof(utmpx.ut_id));
258	} else {
259	    (void)strncpy(utmpx.ut_id, tty, sizeof(utmpx.ut_id));
260	}
261	if (pututxline(&utmpx) == NULL)
262		syslog(LOG_NOTICE, "Cannot update utmpx: %m");
263	endutxent();
264	if (updwtmpx(_PATH_WTMPX, &utmpx) != 0)
265		syslog(LOG_NOTICE, "Cannot update wtmpx: %m");
266}
267
268static void
269dolastlogx(int quiet)
270{
271	struct lastlogx ll;
272	if (!quiet && getlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != NULL) {
273		time_t t = (time_t)ll.ll_tv.tv_sec;
274		(void)printf("Last login: %.24s ", ctime(&t));
275		if (*ll.ll_host != '\0')
276			(void)printf("from %.*s ",
277			    (int)sizeof(ll.ll_host),
278			    ll.ll_host);
279		(void)printf("on %.*s\n",
280		    (int)sizeof(ll.ll_line),
281		    ll.ll_line);
282	}
283	ll.ll_tv = now;
284	(void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
285	if (hostname)
286		(void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
287	else
288		(void)memset(ll.ll_host, '\0', sizeof(ll.ll_host));
289	if (have_ss)
290		ll.ll_ss = ss;
291	else
292		(void)memset(&ll.ll_ss, 0, sizeof(ll.ll_ss));
293	if (updlastlogx(_PATH_LASTLOGX, pwd->pw_uid, &ll) != 0)
294		syslog(LOG_NOTICE, "Cannot update lastlogx: %m");
295}
296#endif
297
298#ifdef SUPPORT_UTMP
299static void
300doutmp(void)
301{
302	struct utmp utmp;
303
304	(void)memset((void *)&utmp, 0, sizeof(utmp));
305	utmp.ut_time = now.tv_sec;
306	(void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
307	if (hostname)
308		(void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
309	(void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
310	login(&utmp);
311}
312
313static void
314dolastlog(int quiet)
315{
316	struct lastlog ll;
317	int fd;
318
319	if ((fd = open(_PATH_LASTLOG, O_RDWR, 0)) >= 0) {
320		(void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)), SEEK_SET);
321		if (!quiet) {
322			if (read(fd, (char *)&ll, sizeof(ll)) == sizeof(ll) &&
323			    ll.ll_time != 0) {
324				(void)printf("Last login: %.24s ",
325				    ctime(&ll.ll_time));
326				if (*ll.ll_host != '\0')
327					(void)printf("from %.*s ",
328					    (int)sizeof(ll.ll_host),
329					    ll.ll_host);
330				(void)printf("on %.*s\n",
331				    (int)sizeof(ll.ll_line), ll.ll_line);
332			}
333			(void)lseek(fd, (off_t)(pwd->pw_uid * sizeof(ll)),
334			    SEEK_SET);
335		}
336		memset((void *)&ll, 0, sizeof(ll));
337		ll.ll_time = now.tv_sec;
338		(void)strncpy(ll.ll_line, tty, sizeof(ll.ll_line));
339		if (hostname)
340			(void)strncpy(ll.ll_host, hostname, sizeof(ll.ll_host));
341		(void)write(fd, (char *)&ll, sizeof(ll));
342		(void)close(fd);
343	}
344}
345#endif
346
347void
348badlogin(const char *name)
349{
350
351	if (failures == 0)
352		return;
353	if (hostname) {
354		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s FROM %s",
355		    failures, failures > 1 ? "S" : "", hostname);
356		syslog(LOG_AUTHPRIV|LOG_NOTICE,
357		    "%d LOGIN FAILURE%s FROM %s, %s",
358		    failures, failures > 1 ? "S" : "", hostname, name);
359	} else {
360		syslog(LOG_NOTICE, "%d LOGIN FAILURE%s ON %s",
361		    failures, failures > 1 ? "S" : "", tty);
362		syslog(LOG_AUTHPRIV|LOG_NOTICE,
363		    "%d LOGIN FAILURE%s ON %s, %s",
364		    failures, failures > 1 ? "S" : "", tty, name);
365	}
366}
367
368const char *
369stypeof(const char *ttyid)
370{
371	struct ttyent *t;
372
373	return (ttyid && (t = getttynam(ttyid)) ? t->ty_type : NULL);
374}
375
376void __dead
377sleepexit(int eval)
378{
379
380	(void)sleep(5);
381	exit(eval);
382}
383
384void
385decode_ss(const char *arg)
386{
387	struct sockaddr_storage *ssp;
388	size_t len = strlen(arg);
389
390	if (len > sizeof(*ssp) * 4 + 1 || len < sizeof(*ssp))
391		errx(EXIT_FAILURE, "Bad argument");
392
393	if ((ssp = malloc(len + 1)) == NULL)
394		err(EXIT_FAILURE, NULL);
395
396	if (strunvis((char *)ssp, arg) != sizeof(*ssp))
397		errx(EXIT_FAILURE, "Decoding error");
398
399	(void)memcpy(&ss, ssp, sizeof(ss));
400	free(ssp);
401	have_ss = 1;
402}
403