xref: /netbsd/libexec/rlogind/rlogind.c (revision bf9ec67e)
1 /*	$NetBSD: rlogind.c,v 1.24 2001/02/04 22:14:13 christos Exp $	*/
2 
3 /*
4  * Copyright (C) 1998 WIDE Project.
5  * 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *    This product includes software developed by WIDE Project and
18  *    its contributors.
19  * 4. Neither the name of the project 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 PROJECT 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 PROJECT 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 /*-
37  * Copyright (c) 1983, 1988, 1989, 1993
38  *	The Regents of the University of California.  All rights reserved.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. All advertising materials mentioning features or use of this software
49  *    must display the following acknowledgement:
50  *	This product includes software developed by the University of
51  *	California, Berkeley and its contributors.
52  * 4. Neither the name of the University nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  */
68 
69 #include <sys/cdefs.h>
70 #ifndef lint
71 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1989, 1993\n\
72 	The Regents of the University of California.  All rights reserved.\n");
73 #if 0
74 static char sccsid[] = "@(#)rlogind.c	8.2 (Berkeley) 4/28/95";
75 #else
76 __RCSID("$NetBSD: rlogind.c,v 1.24 2001/02/04 22:14:13 christos Exp $");
77 #endif
78 #endif /* not lint */
79 
80 /*
81  * remote login server:
82  *	\0
83  *	remuser\0
84  *	locuser\0
85  *	terminal_type/speed\0
86  *	data
87  */
88 
89 #define	FD_SETSIZE	16		/* don't need many bits for select */
90 #include <sys/param.h>
91 #include <sys/stat.h>
92 #include <sys/ioctl.h>
93 #include <signal.h>
94 #include <termios.h>
95 
96 #include <sys/socket.h>
97 #include <netinet/in.h>
98 #include <netinet/in_systm.h>
99 #include <netinet/ip.h>
100 #include <arpa/inet.h>
101 #include <netdb.h>
102 
103 #include <pwd.h>
104 #include <syslog.h>
105 #include <errno.h>
106 #include <stdio.h>
107 #include <unistd.h>
108 #include <stdlib.h>
109 #include <string.h>
110 #include <util.h>
111 #include <utmp.h>
112 #include "pathnames.h"
113 
114 #ifndef TIOCPKT_WINDOW
115 #define TIOCPKT_WINDOW 0x80
116 #endif
117 
118 #define		OPTIONS			"alnL"
119 
120 char	*env[2];
121 #define	NMAX 30
122 char	lusername[NMAX+1], rusername[NMAX+1];
123 static	char term[64] = "TERM=";
124 #define	ENVSIZE	(sizeof("TERM=")-1)	/* skip null for concatenation */
125 int	keepalive = 1;
126 int	check_all = 0;
127 int	log_success = 0;
128 
129 struct	passwd *pwd;
130 
131 void	doit __P((int, struct sockaddr *));
132 int	control __P((int, char *, int));
133 void	protocol __P((int, int));
134 void	cleanup __P((int));
135 void	fatal __P((int, char *, int));
136 int	do_rlogin __P((struct sockaddr *, char *));
137 void	getstr __P((char *, int, char *));
138 void	setup_term __P((int));
139 #if 0
140 int	do_krb_login __P((union sockunion *));
141 #endif
142 void	usage __P((void));
143 int	local_domain __P((char *));
144 char	*topdomain __P((char *));
145 int	main __P((int, char *[]));
146 
147 extern int __check_rhosts_file;
148 extern char *__rcmd_errstr;	/* syslog hook from libc/net/rcmd.c */
149 extern char **environ;
150 
151 int
152 main(argc, argv)
153 	int argc;
154 	char *argv[];
155 {
156 	struct sockaddr_storage from;
157 	int ch, fromlen, on;
158 
159 	openlog("rlogind", LOG_PID, LOG_AUTH);
160 
161 	opterr = 0;
162 	while ((ch = getopt(argc, argv, OPTIONS)) != -1)
163 		switch (ch) {
164 		case 'a':
165 			check_all = 1;
166 			break;
167 		case 'l':
168 			__check_rhosts_file = 0;
169 			break;
170 		case 'n':
171 			keepalive = 0;
172 			break;
173 		case 'L':
174 			log_success = 1;
175 			break;
176 		case '?':
177 		default:
178 			usage();
179 			break;
180 		}
181 	argc -= optind;
182 	argv += optind;
183 
184 	fromlen = sizeof (from); /* xxx */
185 	if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) {
186 		syslog(LOG_ERR,"Can't get peer name of remote host: %m");
187 		fatal(STDERR_FILENO, "Can't get peer name of remote host", 1);
188 	}
189 #ifdef INET6
190 	if (((struct sockaddr *)&from)->sa_family == AF_INET6 &&
191 	    IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&from)->sin6_addr) &&
192 	    sizeof(struct sockaddr_in) <= sizeof(from)) {
193 		struct sockaddr_in sin;
194 		struct sockaddr_in6 *sin6;
195 		const int off = sizeof(struct sockaddr_in6) -
196 		    sizeof(struct sockaddr_in);
197 
198 		sin6 = (struct sockaddr_in6 *)&from;
199 		memset(&sin, 0, sizeof(sin));
200 		sin.sin_family = AF_INET;
201 		sin.sin_len = sizeof(struct sockaddr_in);
202 		memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[off],
203 		    sizeof(sin.sin_addr));
204 		memcpy(&from, &sin, sizeof(sin));
205 		fromlen = sin.sin_len;
206 	}
207 #else
208 	if (((struct sockaddr *)&from)->sa_family == AF_INET6 &&
209 	    IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&from)->sin6_addr)) {
210 		char hbuf[NI_MAXHOST];
211 		if (getnameinfo((struct sockaddr *)&from, fromlen, hbuf,
212 				sizeof(hbuf), NULL, 0, NI_NUMERICHOST) != 0) {
213 			strncpy(hbuf, "invalid", sizeof(hbuf));
214 		}
215 		syslog(LOG_ERR, "malformed \"from\" address (v4 mapped, %s)\n",
216 		    hbuf);
217 		exit(1);
218 	}
219 #endif
220 	on = 1;
221 	if (keepalive &&
222 	    setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof (on)) < 0)
223 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
224 #if defined(IP_TOS)
225 	if (((struct sockaddr *)&from)->sa_family == AF_INET) {
226 		on = IPTOS_LOWDELAY;
227 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&on, sizeof(int)) < 0)
228 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
229 	}
230 #endif
231 	doit(0, (struct sockaddr *)&from);
232 	/* NOTREACHED */
233 #ifdef __GNUC__
234 	exit(0);
235 #endif
236 }
237 
238 int	child;
239 int	netf;
240 char	line[MAXPATHLEN];
241 int	confirmed;
242 
243 struct winsize win = { 0, 0, 0, 0 };
244 
245 
246 void
247 doit(f, fromp)
248 	int f;
249 	struct sockaddr *fromp;
250 {
251 	int master, pid, on = 1;
252 	int authenticated = 0;
253 	char utmphost[UT_HOSTSIZE + 1];
254 	char *hostname;
255 	char hostnamebuf[2 * MAXHOSTNAMELEN + 1];
256 	char c;
257 	char naddr[NI_MAXHOST];
258 	char saddr[NI_MAXHOST];
259 	char raddr[NI_MAXHOST];
260 	int af = fromp->sa_family;
261 	u_int16_t *portp;
262 	struct addrinfo hints, *res, *res0;
263 	int gaierror;
264 #ifdef NI_WITHSCOPEID
265 	const int niflags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
266 #else
267 	const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
268 #endif
269 
270 	alarm(60);
271 	read(f, &c, 1);
272 
273 	if (c != 0)
274 		exit(1);
275 
276 	alarm(0);
277 	switch (af) {
278 	case AF_INET:
279 		portp = &((struct sockaddr_in *)fromp)->sin_port;
280 		break;
281 #ifdef INET6
282 	case AF_INET6:
283 		portp = &((struct sockaddr_in6 *)fromp)->sin6_port;
284 		break;
285 #endif
286 	default:
287 		syslog(LOG_ERR, "malformed \"from\" address (af %d)\n", af);
288 		exit(1);
289 	}
290 	if (getnameinfo((struct sockaddr *)fromp, fromp->sa_len,
291 		    naddr, sizeof(naddr), NULL, 0, niflags) != 0) {
292 		syslog(LOG_ERR, "malformed \"from\" address (af %d)\n", af);
293 		exit(1);
294 	}
295 
296 	if (getnameinfo((struct sockaddr *)fromp, fromp->sa_len,
297 		    saddr, sizeof(saddr), NULL, 0, NI_NAMEREQD) == 0) {
298 		/*
299 		 * If name returned by gethostbyaddr is in our domain,
300 		 * attempt to verify that we haven't been fooled by someone
301 		 * in a remote net; look up the name and check that this
302 		 * address corresponds to the name.
303 		 */
304 		hostname = saddr;
305 		res0 = NULL;
306 		if (check_all || local_domain(saddr)) {
307 			strncpy(hostnamebuf, saddr, sizeof(hostnamebuf) - 1);
308 			hostnamebuf[sizeof(hostnamebuf) - 1] = 0;
309 			memset(&hints, 0, sizeof(hints));
310 			hints.ai_family = fromp->sa_family;
311 			hints.ai_socktype = SOCK_STREAM;
312 			hints.ai_flags = AI_CANONNAME;
313 			gaierror = getaddrinfo(hostnamebuf, "0", &hints, &res0);
314 			if (gaierror) {
315 				syslog(LOG_NOTICE,
316 				    "Couldn't look up address for %s: %s",
317 				    hostnamebuf, gai_strerror(gaierror));
318 				hostname = naddr;
319 			} else {
320 				for (res = res0; res; res = res->ai_next) {
321 					if (res->ai_family != fromp->sa_family)
322 						continue;
323 					if (res->ai_addrlen != fromp->sa_len)
324 						continue;
325 					if (getnameinfo(res->ai_addr,
326 						res->ai_addrlen,
327 						raddr, sizeof(raddr), NULL, 0,
328 						niflags) == 0
329 					 && strcmp(naddr, raddr) == 0) {
330 						hostname = res->ai_canonname
331 							? res->ai_canonname
332 							: saddr;
333 						break;
334 					}
335 				}
336 				if (res == NULL) {
337 					syslog(LOG_NOTICE,
338 					  "Host addr %s not listed for host %s",
339 					    naddr, res0->ai_canonname
340 						    ? res0->ai_canonname
341 						    : saddr);
342 					hostname = naddr;
343 				}
344 			}
345 		}
346 		hostname = strncpy(hostnamebuf, hostname,
347 				   sizeof(hostnamebuf) - 1);
348 		if (res0)
349 			freeaddrinfo(res0);
350 	} else
351 		hostname = strncpy(hostnamebuf, naddr,
352 				   sizeof(hostnamebuf) - 1);
353 
354 	hostnamebuf[sizeof(hostnamebuf) - 1] = '\0';
355 
356 	if (strlen(hostname) < sizeof(utmphost))
357 		(void)strcpy(utmphost, hostname);
358 	else
359 		(void)strncpy(utmphost, hostname, sizeof(utmphost));
360 	utmphost[sizeof(utmphost) - 1] = '\0';
361 
362 	if (ntohs(*portp) >= IPPORT_RESERVED ||
363 	    ntohs(*portp) < IPPORT_RESERVED/2) {
364 		syslog(LOG_NOTICE, "Connection from %s on illegal port",
365 		       naddr);
366 		fatal(f, "Permission denied", 0);
367 	}
368 #ifdef IP_OPTIONS
369 	if (fromp->sa_family == AF_INET) {
370 		u_char optbuf[BUFSIZ/3], *cp;
371 		char lbuf[BUFSIZ], *lp;
372 		int optsize = sizeof(optbuf), ipproto;
373 		struct protoent *ip;
374 
375 		if ((ip = getprotobyname("ip")) != NULL)
376 			ipproto = ip->p_proto;
377 		else
378 			ipproto = IPPROTO_IP;
379 		if (getsockopt(0, ipproto, IP_OPTIONS, (char *)optbuf,
380 		    &optsize) == 0 && optsize != 0) {
381 			lp = lbuf;
382 			for (cp = optbuf; optsize > 0; cp++, optsize--, lp += 3)
383 				sprintf(lp, " %2.2x", *cp);
384 			syslog(LOG_NOTICE,
385 			    "Connection received using IP options (ignored):%s",
386 			    lbuf);
387 			if (setsockopt(0, ipproto, IP_OPTIONS,
388 			    (char *)NULL, optsize) != 0) {
389 				syslog(LOG_ERR,
390 				    "setsockopt IP_OPTIONS NULL: %m");
391 				exit(1);
392 			}
393 		}
394 	}
395 #endif
396 	if (do_rlogin(fromp, hostname) == 0)
397 		authenticated++;
398 	if (confirmed == 0) {
399 		write(f, "", 1);
400 		confirmed = 1;		/* we sent the null! */
401 	}
402 	netf = f;
403 
404 	pid = forkpty(&master, line, NULL, &win);
405 	if (pid < 0) {
406 		if (errno == ENOENT)
407 			fatal(f, "Out of ptys", 0);
408 		else
409 			fatal(f, "Forkpty", 1);
410 	}
411 	if (pid == 0) {
412 		if (f > 2)	/* f should always be 0, but... */
413 			(void) close(f);
414 		setup_term(0);
415 		if (authenticated)
416 			execl(_PATH_LOGIN, "login", "-p",
417 			    "-h", utmphost, "-f", "--", lusername, (char *)0);
418 		else
419 			execl(_PATH_LOGIN, "login", "-p",
420 			    "-h", utmphost, "--", lusername, (char *)0);
421 		fatal(STDERR_FILENO, _PATH_LOGIN, 1);
422 		/*NOTREACHED*/
423 	}
424 	ioctl(f, FIONBIO, &on);
425 	ioctl(master, FIONBIO, &on);
426 	ioctl(master, TIOCPKT, &on);
427 	signal(SIGCHLD, cleanup);
428 	protocol(f, master);
429 	signal(SIGCHLD, SIG_IGN);
430 	cleanup(0);
431 }
432 
433 char	magic[2] = { 0377, 0377 };
434 char	oobdata[] = {TIOCPKT_WINDOW};
435 
436 /*
437  * Handle a "control" request (signaled by magic being present)
438  * in the data stream.  For now, we are only willing to handle
439  * window size changes.
440  */
441 int
442 control(pty, cp, n)
443 	int pty;
444 	char *cp;
445 	int n;
446 {
447 	struct winsize w;
448 
449 	if (n < 4+sizeof (w) || cp[2] != 's' || cp[3] != 's')
450 		return (0);
451 	oobdata[0] &= ~TIOCPKT_WINDOW;	/* we know he heard */
452 	memmove(&w, cp+4, sizeof(w));
453 	w.ws_row = ntohs(w.ws_row);
454 	w.ws_col = ntohs(w.ws_col);
455 	w.ws_xpixel = ntohs(w.ws_xpixel);
456 	w.ws_ypixel = ntohs(w.ws_ypixel);
457 	(void)ioctl(pty, TIOCSWINSZ, &w);
458 	return (4+sizeof (w));
459 }
460 
461 /*
462  * rlogin "protocol" machine.
463  */
464 void
465 protocol(f, p)
466 	int f, p;
467 {
468 	char pibuf[1024+1], fibuf[1024], *pbp = NULL, *fbp = NULL;
469 					/* XXX gcc above */
470 	int pcc = 0, fcc = 0;
471 	int cc, nfd, n;
472 	char cntl;
473 
474 	/*
475 	 * Must ignore SIGTTOU, otherwise we'll stop
476 	 * when we try and set slave pty's window shape
477 	 * (our controlling tty is the master pty).
478 	 */
479 	(void) signal(SIGTTOU, SIG_IGN);
480 	send(f, oobdata, 1, MSG_OOB);	/* indicate new rlogin */
481 	if (f > p)
482 		nfd = f + 1;
483 	else
484 		nfd = p + 1;
485 	if (nfd > FD_SETSIZE) {
486 		syslog(LOG_ERR, "select mask too small, increase FD_SETSIZE");
487 		fatal(f, "internal error (select mask too small)", 0);
488 	}
489 	for (;;) {
490 		fd_set ibits, obits, ebits, *omask;
491 
492 		FD_ZERO(&ebits);
493 		FD_ZERO(&ibits);
494 		FD_ZERO(&obits);
495 		omask = (fd_set *)NULL;
496 		if (fcc) {
497 			FD_SET(p, &obits);
498 			omask = &obits;
499 		} else
500 			FD_SET(f, &ibits);
501 		if (pcc >= 0) {
502 			if (pcc) {
503 				FD_SET(f, &obits);
504 				omask = &obits;
505 			} else
506 				FD_SET(p, &ibits);
507 		}
508 		FD_SET(p, &ebits);
509 		if ((n = select(nfd, &ibits, omask, &ebits, 0)) < 0) {
510 			if (errno == EINTR)
511 				continue;
512 			fatal(f, "select", 1);
513 		}
514 		if (n == 0) {
515 			/* shouldn't happen... */
516 			sleep(5);
517 			continue;
518 		}
519 #define	pkcontrol(c)	((c)&(TIOCPKT_FLUSHWRITE|TIOCPKT_NOSTOP|TIOCPKT_DOSTOP))
520 		if (FD_ISSET(p, &ebits)) {
521 			cc = read(p, &cntl, 1);
522 			if (cc == 1 && pkcontrol(cntl)) {
523 				cntl |= oobdata[0];
524 				send(f, &cntl, 1, MSG_OOB);
525 				if (cntl & TIOCPKT_FLUSHWRITE) {
526 					pcc = 0;
527 					FD_CLR(p, &ibits);
528 				}
529 			}
530 		}
531 		if (FD_ISSET(f, &ibits)) {
532 				fcc = read(f, fibuf, sizeof(fibuf));
533 			if (fcc < 0 && errno == EWOULDBLOCK)
534 				fcc = 0;
535 			else {
536 				char *cp;
537 				int left, n;
538 
539 				if (fcc <= 0)
540 					break;
541 				fbp = fibuf;
542 
543 			top:
544 				for (cp = fibuf; cp < fibuf+fcc-1; cp++)
545 					if (cp[0] == magic[0] &&
546 					    cp[1] == magic[1]) {
547 						left = fcc - (cp-fibuf);
548 						n = control(p, cp, left);
549 						if (n) {
550 							left -= n;
551 							if (left > 0)
552 								memmove(cp,
553 								    cp+n,
554 								    left);
555 							fcc -= n;
556 							goto top; /* n^2 */
557 						}
558 					}
559 				FD_SET(p, &obits);		/* try write */
560 			}
561 		}
562 
563 		if (FD_ISSET(p, &obits) && fcc > 0) {
564 			cc = write(p, fbp, fcc);
565 			if (cc > 0) {
566 				fcc -= cc;
567 				fbp += cc;
568 			}
569 		}
570 
571 		if (FD_ISSET(p, &ibits)) {
572 			pcc = read(p, pibuf, sizeof (pibuf));
573 			pbp = pibuf;
574 			if (pcc < 0 && errno == EWOULDBLOCK)
575 				pcc = 0;
576 			else if (pcc <= 0)
577 				break;
578 			else if (pibuf[0] == 0) {
579 				pbp++, pcc--;
580 					FD_SET(f, &obits);	/* try write */
581 			} else {
582 				if (pkcontrol(pibuf[0])) {
583 					pibuf[0] |= oobdata[0];
584 					send(f, &pibuf[0], 1, MSG_OOB);
585 				}
586 				pcc = 0;
587 			}
588 		}
589 		if ((FD_ISSET(f, &obits)) && pcc > 0) {
590 				cc = write(f, pbp, pcc);
591 			if (cc < 0 && errno == EWOULDBLOCK) {
592 				/*
593 				 * This happens when we try write after read
594 				 * from p, but some old kernels balk at large
595 				 * writes even when select returns true.
596 				 */
597 				if (!FD_ISSET(p, &ibits))
598 					sleep(5);
599 				continue;
600 			}
601 			if (cc > 0) {
602 				pcc -= cc;
603 				pbp += cc;
604 			}
605 		}
606 	}
607 }
608 
609 void
610 cleanup(signo)
611 	int signo;
612 {
613 	char *p, c;
614 
615 	p = line + sizeof(_PATH_DEV) - 1;
616 	if (logout(p))
617 		logwtmp(p, "", "");
618 	(void)chmod(line, 0666);
619 	(void)chown(line, 0, 0);
620 	c = *p; *p = 'p';
621 	(void)chmod(line, 0666);
622 	(void)chown(line, 0, 0);
623 	*p = c;
624 	if (ttyaction(line, "rlogind", "root"))
625 		syslog(LOG_ERR, "%s: ttyaction failed", line);
626 	shutdown(netf, 2);
627 	exit(1);
628 }
629 
630 void
631 fatal(f, msg, syserr)
632 	int f;
633 	char *msg;
634 	int syserr;
635 {
636 	int len;
637 	char buf[BUFSIZ], *bp = buf;
638 
639 	/*
640 	 * Prepend binary one to message if we haven't sent
641 	 * the magic null as confirmation.
642 	 */
643 	if (!confirmed)
644 		*bp++ = '\01';		/* error indicator */
645 	if (syserr)
646 		len = sprintf(bp, "rlogind: %s: %s.\r\n",
647 		    msg, strerror(errno));
648 	else
649 		len = sprintf(bp, "rlogind: %s.\r\n", msg);
650 	(void) write(f, buf, bp + len - buf);
651 	exit(1);
652 }
653 
654 int
655 do_rlogin(dest, host)
656 	struct sockaddr *dest;
657 	char *host;
658 {
659 	int retval;
660 
661 	getstr(rusername, sizeof(rusername), "remuser too long");
662 	getstr(lusername, sizeof(lusername), "locuser too long");
663 	getstr(term+ENVSIZE, sizeof(term)-ENVSIZE, "Terminal type too long");
664 
665 	pwd = getpwnam(lusername);
666 	if (pwd == NULL) {
667 		syslog(LOG_INFO,
668 		    "%s@%s as %s: unknown login.", rusername, host, lusername);
669 		return (-1);
670 	}
671 
672 	retval = iruserok_sa(dest, dest->sa_len, pwd->pw_uid == 0, rusername,
673 		lusername);
674 /* XXX put inet_ntoa(dest->sin_addr.s_addr) into all messages below */
675 	if (retval == 0) {
676 		if (log_success)
677 			syslog(LOG_INFO, "%s@%s as %s: iruserok succeeded",
678 			    rusername, host, lusername);
679 	} else {
680 		if (__rcmd_errstr)
681 			syslog(LOG_INFO, "%s@%s as %s: iruserok failed (%s)",
682 			    rusername, host, lusername, __rcmd_errstr);
683 		else
684 			syslog(LOG_INFO, "%s@%s as %s: iruserok failed",
685 			    rusername, host, lusername);
686 	}
687 	return(retval);
688 }
689 
690 void
691 getstr(buf, cnt, errmsg)
692 	char *buf;
693 	int cnt;
694 	char *errmsg;
695 {
696 	char c;
697 
698 	do {
699 		if (read(0, &c, 1) != 1)
700 			exit(1);
701 		if (--cnt < 0)
702 			fatal(STDOUT_FILENO, errmsg, 0);
703 		*buf++ = c;
704 	} while (c != 0);
705 }
706 
707 
708 void
709 setup_term(fd)
710 	int fd;
711 {
712 	char *cp = index(term+ENVSIZE, '/');
713 	char *speed;
714 	struct termios tt;
715 
716 #ifndef notyet
717 	tcgetattr(fd, &tt);
718 	if (cp) {
719 		*cp++ = '\0';
720 		speed = cp;
721 		cp = index(speed, '/');
722 		if (cp)
723 			*cp++ = '\0';
724 		cfsetspeed(&tt, atoi(speed));
725 	}
726 
727 	tt.c_iflag = TTYDEF_IFLAG;
728 	tt.c_oflag = TTYDEF_OFLAG;
729 	tt.c_lflag = TTYDEF_LFLAG;
730 	tcsetattr(fd, TCSAFLUSH, &tt);
731 #else
732 	if (cp) {
733 		*cp++ = '\0';
734 		speed = cp;
735 		cp = index(speed, '/');
736 		if (cp)
737 			*cp++ = '\0';
738 		tcgetattr(fd, &tt);
739 		cfsetspeed(&tt, atoi(speed));
740 		tcsetattr(fd, TCSAFLUSH, &tt);
741 	}
742 #endif
743 
744 	env[0] = term;
745 	env[1] = 0;
746 	environ = env;
747 }
748 
749 
750 void
751 usage()
752 {
753 	syslog(LOG_ERR, "usage: rlogind [-alnL]");
754 }
755 
756 /*
757  * Check whether host h is in our local domain,
758  * defined as sharing the last two components of the domain part,
759  * or the entire domain part if the local domain has only one component.
760  * If either name is unqualified (contains no '.'),
761  * assume that the host is local, as it will be
762  * interpreted as such.
763  */
764 int
765 local_domain(h)
766 	char *h;
767 {
768 	char localhost[MAXHOSTNAMELEN + 1];
769 	char *p1, *p2;
770 
771 	localhost[0] = 0;
772 	(void) gethostname(localhost, sizeof(localhost));
773 	localhost[sizeof(localhost) - 1] = '\0';
774 	p1 = topdomain(localhost);
775 	p2 = topdomain(h);
776 	if (p1 == NULL || p2 == NULL || !strcasecmp(p1, p2))
777 		return (1);
778 	return (0);
779 }
780 
781 char *
782 topdomain(h)
783 	char *h;
784 {
785 	char *p;
786 	char *maybe = NULL;
787 	int dots = 0;
788 
789 	for (p = h + strlen(h); p >= h; p--) {
790 		if (*p == '.') {
791 			if (++dots == 2)
792 				return (p);
793 			maybe = p;
794 		}
795 	}
796 	return (maybe);
797 }
798