xref: /netbsd-src/usr.sbin/inetd/inetd.c (revision 4b71a66d0f279143147d63ebfcfd8a59499a3684)
1 /*	$NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998, 2003 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9  * NASA Ames Research Center and by Matthias Scheler.
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  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * Copyright (c) 1983, 1991, 1993, 1994
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  */
61 
62 #include <sys/cdefs.h>
63 #ifndef lint
64 __COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\n\
65 	The Regents of the University of California.  All rights reserved.\n");
66 #if 0
67 static char sccsid[] = "@(#)inetd.c	8.4 (Berkeley) 4/13/94";
68 #else
69 __RCSID("$NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland Exp $");
70 #endif
71 #endif /* not lint */
72 
73 /*
74  * Inetd - Internet super-server
75  *
76  * This program invokes all internet services as needed.  Connection-oriented
77  * services are invoked each time a connection is made, by creating a process.
78  * This process is passed the connection as file descriptor 0 and is expected
79  * to do a getpeername to find out the source host and port.
80  *
81  * Datagram oriented services are invoked when a datagram
82  * arrives; a process is created and passed a pending message
83  * on file descriptor 0.  Datagram servers may either connect
84  * to their peer, freeing up the original socket for inetd
85  * to receive further messages on, or ``take over the socket'',
86  * processing all arriving datagrams and, eventually, timing
87  * out.	 The first type of server is said to be ``multi-threaded'';
88  * the second type of server ``single-threaded''.
89  *
90  * Inetd uses a configuration file which is read at startup
91  * and, possibly, at some later time in response to a hangup signal.
92  * The configuration file is ``free format'' with fields given in the
93  * order shown below.  Continuation lines for an entry must being with
94  * a space or tab.  All fields must be present in each entry.
95  *
96  *	service name			must be in /etc/services or must
97  *					name a tcpmux service
98  *	socket type			stream/dgram/raw/rdm/seqpacket
99  *	protocol			must be in /etc/protocols
100  *	wait/nowait[:max]		single-threaded/multi-threaded, max #
101  *	user[:group]			user/group to run daemon as
102  *	server program			full path name
103  *	server program arguments	maximum of MAXARGS (20)
104  *
105  * For RPC services
106  *      service name/version            must be in /etc/rpc
107  *	socket type			stream/dgram/raw/rdm/seqpacket
108  *	protocol			must be in /etc/protocols
109  *	wait/nowait[:max]		single-threaded/multi-threaded
110  *	user[:group]			user to run daemon as
111  *	server program			full path name
112  *	server program arguments	maximum of MAXARGS (20)
113  *
114  * For non-RPC services, the "service name" can be of the form
115  * hostaddress:servicename, in which case the hostaddress is used
116  * as the host portion of the address to listen on.  If hostaddress
117  * consists of a single `*' character, INADDR_ANY is used.
118  *
119  * A line can also consist of just
120  *	hostaddress:
121  * where hostaddress is as in the preceding paragraph.  Such a line must
122  * have no further fields; the specified hostaddress is remembered and
123  * used for all further lines that have no hostaddress specified,
124  * until the next such line (or EOF).  (This is why * is provided to
125  * allow explicit specification of INADDR_ANY.)  A line
126  *	*:
127  * is implicitly in effect at the beginning of the file.
128  *
129  * The hostaddress specifier may (and often will) contain dots;
130  * the service name must not.
131  *
132  * For RPC services, host-address specifiers are accepted and will
133  * work to some extent; however, because of limitations in the
134  * portmapper interface, it will not work to try to give more than
135  * one line for any given RPC service, even if the host-address
136  * specifiers are different.
137  *
138  * TCP services without official port numbers are handled with the
139  * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
140  * requests. When a connection is made from a foreign host, the service
141  * requested is passed to tcpmux, which looks it up in the servtab list
142  * and returns the proper entry for the service. Tcpmux returns a
143  * negative reply if the service doesn't exist, otherwise the invoked
144  * server is expected to return the positive reply if the service type in
145  * inetd.conf file has the prefix "tcpmux/". If the service type has the
146  * prefix "tcpmux/+", tcpmux will return the positive reply for the
147  * process; this is for compatibility with older server code, and also
148  * allows you to invoke programs that use stdin/stdout without putting any
149  * special server code in them. Services that use tcpmux are "nowait"
150  * because they do not have a well-known port and hence cannot listen
151  * for new requests.
152  *
153  * Comment lines are indicated by a `#' in column 1.
154  *
155  * #ifdef IPSEC
156  * Comment lines that start with "#@" denote IPsec policy string, as described
157  * in ipsec_set_policy(3).  This will affect all the following items in
158  * inetd.conf(8).  To reset the policy, just use "#@" line.  By default,
159  * there's no IPsec policy.
160  * #endif
161  */
162 
163 /*
164  * Here's the scoop concerning the user:group feature:
165  *
166  * 1) set-group-option off.
167  *
168  * 	a) user = root:	NO setuid() or setgid() is done
169  *
170  * 	b) other:	setuid()
171  * 			setgid(primary group as found in passwd)
172  * 			initgroups(name, primary group)
173  *
174  * 2) set-group-option on.
175  *
176  * 	a) user = root:	NO setuid()
177  * 			setgid(specified group)
178  * 			NO initgroups()
179  *
180  * 	b) other:	setuid()
181  * 			setgid(specified group)
182  * 			initgroups(name, specified group)
183  *
184  */
185 
186 #include <sys/param.h>
187 #include <sys/stat.h>
188 #include <sys/ioctl.h>
189 #include <sys/socket.h>
190 #include <sys/un.h>
191 #include <sys/wait.h>
192 #include <sys/time.h>
193 #include <sys/resource.h>
194 #include <sys/event.h>
195 
196 #ifndef RLIMIT_NOFILE
197 #define RLIMIT_NOFILE	RLIMIT_OFILE
198 #endif
199 
200 #ifndef NO_RPC
201 #define RPC
202 #endif
203 
204 #include <net/if.h>
205 
206 #include <netinet/in.h>
207 #include <arpa/inet.h>
208 #ifdef RPC
209 #include <rpc/rpc.h>
210 #include <rpc/rpcb_clnt.h>
211 #include <netconfig.h>
212 #endif
213 
214 #include <ctype.h>
215 #include <errno.h>
216 #include <fcntl.h>
217 #include <grp.h>
218 #include <netdb.h>
219 #include <pwd.h>
220 #include <signal.h>
221 #include <stdio.h>
222 #include <stdlib.h>
223 #include <string.h>
224 #include <syslog.h>
225 #include <unistd.h>
226 #include <util.h>
227 #include <ifaddrs.h>
228 
229 #include "pathnames.h"
230 
231 #ifdef IPSEC
232 #include <netinet6/ipsec.h>
233 #ifndef IPSEC_POLICY_IPSEC	/* no ipsec support on old ipsec */
234 #undef IPSEC
235 #endif
236 #include "ipsec.h"
237 #endif
238 
239 #ifdef LIBWRAP
240 # include <tcpd.h>
241 #ifndef LIBWRAP_ALLOW_FACILITY
242 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH
243 #endif
244 #ifndef LIBWRAP_ALLOW_SEVERITY
245 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO
246 #endif
247 #ifndef LIBWRAP_DENY_FACILITY
248 # define LIBWRAP_DENY_FACILITY LOG_AUTH
249 #endif
250 #ifndef LIBWRAP_DENY_SEVERITY
251 # define LIBWRAP_DENY_SEVERITY LOG_WARNING
252 #endif
253 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
254 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
255 #endif
256 
257 #define	TOOMANY		40		/* don't start more than TOOMANY */
258 #define	CNT_INTVL	60		/* servers in CNT_INTVL sec. */
259 #define	RETRYTIME	(60*10)		/* retry after bind or server fail */
260 
261 #define	A_CNT(a)	(sizeof (a) / sizeof (a[0]))
262 
263 int	debug;
264 #ifdef LIBWRAP
265 int	lflag;
266 #endif
267 int	maxsock;
268 int	kq;
269 int	options;
270 int	timingout;
271 struct	servent *sp;
272 char	*curdom;
273 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
274 
275 #ifndef OPEN_MAX
276 #define OPEN_MAX	64
277 #endif
278 
279 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
280 #define FD_MARGIN	(8)
281 rlim_t		rlim_ofile_cur = OPEN_MAX;
282 
283 #ifdef RLIMIT_NOFILE
284 struct rlimit	rlim_ofile;
285 #endif
286 
287 struct kevent	changebuf[64];
288 size_t		changes;
289 
290 struct	servtab {
291 	char	*se_hostaddr;		/* host address to listen on */
292 	char	*se_service;		/* name of service */
293 	int	se_socktype;		/* type of socket to use */
294 	int	se_family;		/* address family */
295 	char	*se_proto;		/* protocol used */
296 	int	se_sndbuf;		/* sndbuf size */
297 	int	se_rcvbuf;		/* rcvbuf size */
298 	int	se_rpcprog;		/* rpc program number */
299 	int	se_rpcversl;		/* rpc program lowest version */
300 	int	se_rpcversh;		/* rpc program highest version */
301 #define isrpcservice(sep)	((sep)->se_rpcversl != 0)
302 	pid_t	se_wait;		/* single threaded server */
303 	short	se_checked;		/* looked at during merge */
304 	char	*se_user;		/* user name to run as */
305 	char	*se_group;		/* group name to run as */
306 	struct	biltin *se_bi;		/* if built-in, description */
307 	char	*se_server;		/* server program */
308 #define	MAXARGV 20
309 	char	*se_argv[MAXARGV+1];	/* program arguments */
310 #ifdef IPSEC
311 	char	*se_policy;		/* IPsec poilcy string */
312 #endif
313 	int	se_fd;			/* open descriptor */
314 	int	se_type;		/* type */
315 	union {
316 		struct	sockaddr se_un_ctrladdr;
317 		struct	sockaddr_in se_un_ctrladdr_in;
318 		struct	sockaddr_in6 se_un_ctrladdr_in6;
319 		struct	sockaddr_un se_un_ctrladdr_un;
320 	} se_un;			/* bound address */
321 #define se_ctrladdr	se_un.se_un_ctrladdr
322 #define se_ctrladdr_in	se_un.se_un_ctrladdr_in
323 #define se_ctrladdr_un	se_un.se_un_ctrladdr_un
324 	int	se_ctrladdr_size;
325 	int	se_max;			/* max # of instances of this service */
326 	int	se_count;		/* number started since se_time */
327 	struct	timeval se_time;	/* start of se_count */
328 #ifdef MULOG
329 	int	se_log;
330 #define MULOG_RFC931	0x40000000
331 #endif
332 	struct	servtab *se_next;
333 } *servtab;
334 
335 #define NORM_TYPE	0
336 #define MUX_TYPE	1
337 #define MUXPLUS_TYPE	2
338 #define FAITH_TYPE	3
339 #define ISMUX(sep)	(((sep)->se_type == MUX_TYPE) || \
340 			 ((sep)->se_type == MUXPLUS_TYPE))
341 #define ISMUXPLUS(sep)	((sep)->se_type == MUXPLUS_TYPE)
342 
343 
344 static void	chargen_dg(int, struct servtab *);
345 static void	chargen_stream(int, struct servtab *);
346 static void	close_sep(struct servtab *);
347 static void	config(void);
348 static void	daytime_dg(int, struct servtab *);
349 static void	daytime_stream(int, struct servtab *);
350 static void	discard_dg(int, struct servtab *);
351 static void	discard_stream(int, struct servtab *);
352 static void	echo_dg(int, struct servtab *);
353 static void	echo_stream(int, struct servtab *);
354 static void	endconfig(void);
355 static struct servtab *enter(struct servtab *);
356 static void	freeconfig(struct servtab *);
357 static struct servtab *getconfigent(void);
358 static void	goaway(void);
359 static void	machtime_dg(int, struct servtab *);
360 static void	machtime_stream(int, struct servtab *);
361 static char    *newstr(char *);
362 static char    *nextline(FILE *);
363 static void	print_service(char *, struct servtab *);
364 static void	reapchild(void);
365 static void	retry(void);
366 static void	run_service(int, struct servtab *, int);
367 static int	setconfig(void);
368 static void	setup(struct servtab *);
369 static char    *sskip(char **);
370 static char    *skip(char **);
371 static void	tcpmux(int, struct servtab *);
372 static void	usage(void);
373 static void	register_rpc(struct servtab *);
374 static void	unregister_rpc(struct servtab *);
375 static void	bump_nofile(void);
376 static void	inetd_setproctitle(char *, int);
377 static void	initring(void);
378 static uint32_t	machtime(void);
379 static int	port_good_dg(struct sockaddr *);
380 static int 	dg_broadcast(struct in_addr *);
381 static int	my_kevent(const struct kevent *, size_t, struct kevent *,
382 		size_t);
383 static struct kevent *	allocchange(void);
384 static int	getline(int, char *, int);
385 static void	spawn(struct servtab *, int);
386 #ifdef MULOG
387 static void	dolog(struct servtab *, int);
388 static void	timeout(int);
389 static char    *rfc931_name(struct sockaddr *, int);
390 #endif
391 
392 struct biltin {
393 	char	*bi_service;		/* internally provided service name */
394 	int	bi_socktype;		/* type of socket supported */
395 	short	bi_fork;		/* 1 if should fork before call */
396 	short	bi_wait;		/* 1 if should wait for child */
397 	void	(*bi_fn)(int, struct servtab *);
398 					/* function which performs it */
399 } biltins[] = {
400 	/* Echo received data */
401 	{ "echo",	SOCK_STREAM,	1, 0,	echo_stream },
402 	{ "echo",	SOCK_DGRAM,	0, 0,	echo_dg },
403 
404 	/* Internet /dev/null */
405 	{ "discard",	SOCK_STREAM,	1, 0,	discard_stream },
406 	{ "discard",	SOCK_DGRAM,	0, 0,	discard_dg },
407 
408 	/* Return 32 bit time since 1970 */
409 	{ "time",	SOCK_STREAM,	0, 0,	machtime_stream },
410 	{ "time",	SOCK_DGRAM,	0, 0,	machtime_dg },
411 
412 	/* Return human-readable time */
413 	{ "daytime",	SOCK_STREAM,	0, 0,	daytime_stream },
414 	{ "daytime",	SOCK_DGRAM,	0, 0,	daytime_dg },
415 
416 	/* Familiar character generator */
417 	{ "chargen",	SOCK_STREAM,	1, 0,	chargen_stream },
418 	{ "chargen",	SOCK_DGRAM,	0, 0,	chargen_dg },
419 
420 	{ "tcpmux",	SOCK_STREAM,	1, 0,	tcpmux },
421 
422 	{ NULL }
423 };
424 
425 /* list of "bad" ports. I.e. ports that are most obviously used for
426  * "cycling packets" denial of service attacks. See /etc/services.
427  * List must end with port number "0".
428  */
429 
430 u_int16_t bad_ports[] =  { 7, 9, 13, 19, 37, 0 };
431 
432 
433 #define NUMINT	(sizeof(intab) / sizeof(struct inent))
434 char	*CONFIG = _PATH_INETDCONF;
435 
436 static int my_signals[] =
437     { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE };
438 
439 int
440 main(int argc, char *argv[])
441 {
442 	int		ch, n, reload = 1;
443 
444 	while ((ch = getopt(argc, argv,
445 #ifdef LIBWRAP
446 					"dl"
447 #else
448 					"d"
449 #endif
450 					   )) != -1)
451 		switch(ch) {
452 		case 'd':
453 			debug = 1;
454 			options |= SO_DEBUG;
455 			break;
456 #ifdef LIBWRAP
457 		case 'l':
458 			lflag = 1;
459 			break;
460 #endif
461 		case '?':
462 		default:
463 			usage();
464 		}
465 	argc -= optind;
466 	argv += optind;
467 
468 	if (argc > 0)
469 		CONFIG = argv[0];
470 
471 	if (!debug)
472 		daemon(0, 0);
473 	openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
474 	pidfile(NULL);
475 
476 	kq = kqueue();
477 	if (kq < 0) {
478 		syslog(LOG_ERR, "kqueue: %m");
479 		return (EXIT_FAILURE);
480 	}
481 
482 #ifdef RLIMIT_NOFILE
483 	if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
484 		syslog(LOG_ERR, "getrlimit: %m");
485 	} else {
486 		rlim_ofile_cur = rlim_ofile.rlim_cur;
487 		if (rlim_ofile_cur == RLIM_INFINITY)	/* ! */
488 			rlim_ofile_cur = OPEN_MAX;
489 	}
490 #endif
491 
492 	for (n = 0; n < (int)A_CNT(my_signals); n++) {
493 		int	signum;
494 
495 		signum = my_signals[n];
496 		if (signum != SIGCHLD)
497 			(void) signal(signum, SIG_IGN);
498 
499 		if (signum != SIGPIPE) {
500 			struct kevent	*ev;
501 
502 			ev = allocchange();
503 			EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
504 			    0, 0, 0);
505 		}
506 	}
507 
508 	for (;;) {
509 		int		ctrl;
510 		struct kevent	eventbuf[64], *ev;
511 		struct servtab	*sep;
512 
513 		if (reload) {
514 			reload = 0;
515 			config();
516 		}
517 
518 		n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf));
519 		changes = 0;
520 
521 		for (ev = eventbuf; n > 0; ev++, n--) {
522 			if (ev->filter == EVFILT_SIGNAL) {
523 				switch (ev->ident) {
524 				case SIGALRM:
525 					retry();
526 					break;
527 				case SIGCHLD:
528 					reapchild();
529 					break;
530 				case SIGTERM:
531 				case SIGINT:
532 					goaway();
533 					break;
534 				case SIGHUP:
535 					reload = 1;
536 					break;
537 				}
538 				continue;
539 			}
540 			if (ev->filter != EVFILT_READ)
541 				continue;
542 			sep = (struct servtab *)ev->udata;
543 			/* Paranoia */
544 			if ((int)ev->ident != sep->se_fd)
545 				continue;
546 			if (debug)
547 				fprintf(stderr, "someone wants %s\n",
548 				    sep->se_service);
549 			if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
550 				/* XXX here do the libwrap check-before-accept*/
551 				ctrl = accept(sep->se_fd, NULL, NULL);
552 				if (debug)
553 					fprintf(stderr, "accept, ctrl %d\n",
554 					    ctrl);
555 				if (ctrl < 0) {
556 					if (errno != EINTR)
557 						syslog(LOG_WARNING,
558 						    "accept (for %s): %m",
559 						    sep->se_service);
560 					continue;
561 				}
562 			} else
563 				ctrl = sep->se_fd;
564 			spawn(sep, ctrl);
565 		}
566 	}
567 }
568 
569 static void
570 spawn(struct servtab *sep, int ctrl)
571 {
572 	int dofork;
573 	pid_t pid;
574 
575 	pid = 0;
576 #ifdef LIBWRAP_INTERNAL
577 	dofork = 1;
578 #else
579 	dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
580 #endif
581 	if (dofork) {
582 		if (sep->se_count++ == 0)
583 			(void)gettimeofday(&sep->se_time, NULL);
584 		else if (sep->se_count >= sep->se_max) {
585 			struct timeval now;
586 
587 			(void)gettimeofday(&now, NULL);
588 			if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) {
589 				sep->se_time = now;
590 				sep->se_count = 1;
591 			} else {
592 				syslog(LOG_ERR,
593 				    "%s/%s max spawn rate (%d in %d seconds) "
594 				    "exceeded; service not started",
595 				    sep->se_service, sep->se_proto,
596 				    sep->se_max, CNT_INTVL);
597 				if (!sep->se_wait && sep->se_socktype ==
598 				    SOCK_STREAM)
599 					close(ctrl);
600 				close_sep(sep);
601 				if (!timingout) {
602 					timingout = 1;
603 					alarm(RETRYTIME);
604 				}
605 				return;
606 			}
607 		}
608 		pid = fork();
609 		if (pid < 0) {
610 			syslog(LOG_ERR, "fork: %m");
611 			if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
612 				close(ctrl);
613 			sleep(1);
614 			return;
615 		}
616 		if (pid != 0 && sep->se_wait) {
617 			struct kevent	*ev;
618 
619 			sep->se_wait = pid;
620 			ev = allocchange();
621 			EV_SET(ev, sep->se_fd, EVFILT_READ,
622 			    EV_DELETE, 0, 0, 0);
623 		}
624 		if (pid == 0) {
625 			size_t	n;
626 
627 			for (n = 0; n < A_CNT(my_signals); n++)
628 				(void) signal(my_signals[n], SIG_DFL);
629 			if (debug)
630 				setsid();
631 		}
632 	}
633 	if (pid == 0) {
634 		run_service(ctrl, sep, dofork);
635 		if (dofork)
636 			exit(0);
637 	}
638 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
639 		close(ctrl);
640 }
641 
642 static void
643 run_service(int ctrl, struct servtab *sep, int didfork)
644 {
645 	struct passwd *pwd;
646 	struct group *grp = NULL;	/* XXX gcc */
647 	char buf[NI_MAXSERV];
648 	struct servtab *s;
649 #ifdef LIBWRAP
650 	struct request_info req;
651 	int denied;
652 	char *service = NULL;	/* XXX gcc */
653 #endif
654 
655 #ifdef LIBWRAP
656 #ifndef LIBWRAP_INTERNAL
657 	if (sep->se_bi == 0)
658 #endif
659 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
660 		request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
661 		    sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
662 		fromhost(&req);
663 		denied = !hosts_access(&req);
664 		if (denied || lflag) {
665 			if (getnameinfo(&sep->se_ctrladdr,
666 					sep->se_ctrladdr.sa_len, NULL, 0,
667 					buf, sizeof(buf), 0) != 0) {
668 				/* shouldn't happen */
669 				(void)snprintf(buf, sizeof buf, "%d",
670 				    ntohs(sep->se_ctrladdr_in.sin_port));
671 			}
672 			service = buf;
673 		}
674 		if (denied) {
675 			syslog(deny_severity,
676 			    "refused connection from %.500s, service %s (%s)",
677 			    eval_client(&req), service, sep->se_proto);
678 			goto reject;
679 		}
680 		if (lflag) {
681 			syslog(allow_severity,
682 			    "connection from %.500s, service %s (%s)",
683 			    eval_client(&req), service, sep->se_proto);
684 		}
685 	}
686 #endif /* LIBWRAP */
687 
688 	if (sep->se_bi) {
689 		if (didfork) {
690 			for (s = servtab; s; s = s->se_next)
691 				if (s->se_fd != -1 && s->se_fd != ctrl)
692 					close(s->se_fd);
693 		}
694 		(*sep->se_bi->bi_fn)(ctrl, sep);
695 	} else {
696 		if ((pwd = getpwnam(sep->se_user)) == NULL) {
697 			syslog(LOG_ERR, "%s/%s: %s: No such user",
698 			    sep->se_service, sep->se_proto, sep->se_user);
699 			goto reject;
700 		}
701 		if (sep->se_group &&
702 		    (grp = getgrnam(sep->se_group)) == NULL) {
703 			syslog(LOG_ERR, "%s/%s: %s: No such group",
704 			    sep->se_service, sep->se_proto, sep->se_group);
705 			goto reject;
706 		}
707 		if (pwd->pw_uid) {
708 			if (sep->se_group)
709 				pwd->pw_gid = grp->gr_gid;
710 			if (setgid(pwd->pw_gid) < 0) {
711 				syslog(LOG_ERR,
712 				 "%s/%s: can't set gid %d: %m", sep->se_service,
713 				    sep->se_proto, pwd->pw_gid);
714 				goto reject;
715 			}
716 			(void) initgroups(pwd->pw_name,
717 			    pwd->pw_gid);
718 			if (setuid(pwd->pw_uid) < 0) {
719 				syslog(LOG_ERR,
720 				 "%s/%s: can't set uid %d: %m", sep->se_service,
721 				    sep->se_proto, pwd->pw_uid);
722 				goto reject;
723 			}
724 		} else if (sep->se_group) {
725 			(void) setgid((gid_t)grp->gr_gid);
726 		}
727 		if (debug)
728 			fprintf(stderr, "%d execl %s\n",
729 			    getpid(), sep->se_server);
730 #ifdef MULOG
731 		if (sep->se_log)
732 			dolog(sep, ctrl);
733 #endif
734 		/* Set our control descriptor to not close-on-exec... */
735 		if (fcntl(ctrl, F_SETFD, 0) < 0)
736 			syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m");
737 		/* ...and dup it to stdin, stdout, and stderr. */
738 		if (ctrl != 0) {
739 			dup2(ctrl, 0);
740 			close(ctrl);
741 			ctrl = 0;
742 		}
743 		dup2(0, 1);
744 		dup2(0, 2);
745 #ifdef RLIMIT_NOFILE
746 		if (rlim_ofile.rlim_cur != rlim_ofile_cur &&
747 		    setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
748 			syslog(LOG_ERR, "setrlimit: %m");
749 #endif
750 		execv(sep->se_server, sep->se_argv);
751 		syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server);
752 	reject:
753 		if (sep->se_socktype != SOCK_STREAM)
754 			recv(ctrl, buf, sizeof (buf), 0);
755 		_exit(1);
756 	}
757 }
758 
759 static void
760 reapchild(void)
761 {
762 	int status;
763 	pid_t pid;
764 	struct servtab *sep;
765 
766 	for (;;) {
767 		pid = wait3(&status, WNOHANG, NULL);
768 		if (pid <= 0)
769 			break;
770 		if (debug)
771 			(void) fprintf(stderr, "%d reaped, status %#x\n",
772 			    pid, status);
773 		for (sep = servtab; sep != NULL; sep = sep->se_next)
774 			if (sep->se_wait == pid) {
775 				struct kevent	*ev;
776 
777 				if (WIFEXITED(status) && WEXITSTATUS(status))
778 					syslog(LOG_WARNING,
779 					    "%s: exit status 0x%x",
780 					    sep->se_server, WEXITSTATUS(status));
781 				else if (WIFSIGNALED(status))
782 					syslog(LOG_WARNING,
783 					    "%s: exit signal 0x%x",
784 					    sep->se_server, WTERMSIG(status));
785 				sep->se_wait = 1;
786 				ev = allocchange();
787 				EV_SET(ev, sep->se_fd, EVFILT_READ,
788 				    EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep);
789 				if (debug)
790 					fprintf(stderr, "restored %s, fd %d\n",
791 					    sep->se_service, sep->se_fd);
792 			}
793 	}
794 }
795 
796 static void
797 config(void)
798 {
799 	struct servtab *sep, *cp, **sepp;
800 	size_t n;
801 
802 	if (!setconfig()) {
803 		syslog(LOG_ERR, "%s: %m", CONFIG);
804 		return;
805 	}
806 	for (sep = servtab; sep != NULL; sep = sep->se_next)
807 		sep->se_checked = 0;
808 	while ((cp = getconfigent())) {
809 		for (sep = servtab; sep != NULL; sep = sep->se_next)
810 			if (strcmp(sep->se_service, cp->se_service) == 0 &&
811 			    strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 &&
812 			    strcmp(sep->se_proto, cp->se_proto) == 0 &&
813 			    ISMUX(sep) == ISMUX(cp))
814 				break;
815 		if (sep != NULL) {
816 			int i;
817 
818 #define SWAP(type, a, b) {type c = a; a = b; b = c;}
819 
820 			/*
821 			 * sep->se_wait may be holding the pid of a daemon
822 			 * that we're waiting for.  If so, don't overwrite
823 			 * it unless the config file explicitly says don't
824 			 * wait.
825 			 */
826 			if (cp->se_bi == 0 &&
827 			    (sep->se_wait == 1 || cp->se_wait == 0))
828 				sep->se_wait = cp->se_wait;
829 			SWAP(char *, sep->se_user, cp->se_user);
830 			SWAP(char *, sep->se_group, cp->se_group);
831 			SWAP(char *, sep->se_server, cp->se_server);
832 			for (i = 0; i < MAXARGV; i++)
833 				SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
834 #ifdef IPSEC
835 			SWAP(char *, sep->se_policy, cp->se_policy);
836 #endif
837 			SWAP(int, cp->se_type, sep->se_type);
838 			SWAP(int, cp->se_max, sep->se_max);
839 #undef SWAP
840 			if (isrpcservice(sep))
841 				unregister_rpc(sep);
842 			sep->se_rpcversl = cp->se_rpcversl;
843 			sep->se_rpcversh = cp->se_rpcversh;
844 			freeconfig(cp);
845 			if (debug)
846 				print_service("REDO", sep);
847 		} else {
848 			sep = enter(cp);
849 			if (debug)
850 				print_service("ADD ", sep);
851 		}
852 		sep->se_checked = 1;
853 
854 		switch (sep->se_family) {
855 		case AF_LOCAL:
856 			if (sep->se_fd != -1)
857 				break;
858 			n = strlen(sep->se_service);
859 			if (n > sizeof(sep->se_ctrladdr_un.sun_path)) {
860 				syslog(LOG_ERR, "%s: address too long",
861 				    sep->se_service);
862 				sep->se_checked = 0;
863 				continue;
864 			}
865 			(void)unlink(sep->se_service);
866 			strncpy(sep->se_ctrladdr_un.sun_path,
867 			    sep->se_service, n);
868 			sep->se_ctrladdr_un.sun_family = AF_LOCAL;
869 			sep->se_ctrladdr_size = n +
870 			    sizeof(sep->se_ctrladdr_un) -
871 			    sizeof(sep->se_ctrladdr_un.sun_path);
872 			if (!ISMUX(sep))
873 				setup(sep);
874 			break;
875 		case AF_INET:
876 #ifdef INET6
877 		case AF_INET6:
878 #endif
879 		    {
880 			struct addrinfo hints, *res;
881 			char *host, *port;
882 			int error;
883 			int s;
884 
885 			/* check if the family is supported */
886 			s = socket(sep->se_family, SOCK_DGRAM, 0);
887 			if (s < 0) {
888 				syslog(LOG_WARNING,
889 				    "%s/%s: %s: the address family is not "
890 				    "supported by the kernel",
891 				    sep->se_service, sep->se_proto,
892 				    sep->se_hostaddr);
893 				sep->se_checked = 0;
894 				continue;
895 			}
896 			close(s);
897 
898 			memset(&hints, 0, sizeof(hints));
899 			hints.ai_family = sep->se_family;
900 			hints.ai_socktype = sep->se_socktype;
901 			hints.ai_flags = AI_PASSIVE;
902 			if (!strcmp(sep->se_hostaddr, "*"))
903 				host = NULL;
904 			else
905 				host = sep->se_hostaddr;
906 			if (isrpcservice(sep) || ISMUX(sep))
907 				port = "0";
908 			else
909 				port = sep->se_service;
910 			error = getaddrinfo(host, port, &hints, &res);
911 			if (error) {
912 				if (error == EAI_SERVICE) {
913 					/* gai_strerror not friendly enough */
914 					syslog(LOG_WARNING, "%s/%s: "
915 					    "unknown service",
916 					    sep->se_service, sep->se_proto);
917 				} else {
918 					syslog(LOG_ERR, "%s/%s: %s: %s",
919 					    sep->se_service, sep->se_proto,
920 					    sep->se_hostaddr,
921 					    gai_strerror(error));
922 				}
923 				sep->se_checked = 0;
924 				continue;
925 			}
926 			if (res->ai_next) {
927 				syslog(LOG_ERR,
928 					"%s/%s: %s: resolved to multiple addr",
929 				    sep->se_service, sep->se_proto,
930 				    sep->se_hostaddr);
931 				sep->se_checked = 0;
932 				freeaddrinfo(res);
933 				continue;
934 			}
935 			memcpy(&sep->se_ctrladdr, res->ai_addr,
936 				res->ai_addrlen);
937 			if (ISMUX(sep)) {
938 				sep->se_fd = -1;
939 				freeaddrinfo(res);
940 				continue;
941 			}
942 			sep->se_ctrladdr_size = res->ai_addrlen;
943 			freeaddrinfo(res);
944 #ifdef RPC
945 			if (isrpcservice(sep)) {
946 				struct rpcent *rp;
947 
948 				sep->se_rpcprog = atoi(sep->se_service);
949 				if (sep->se_rpcprog == 0) {
950 					rp = getrpcbyname(sep->se_service);
951 					if (rp == 0) {
952 						syslog(LOG_ERR,
953 						    "%s/%s: unknown service",
954 						    sep->se_service,
955 						    sep->se_proto);
956 						sep->se_checked = 0;
957 						continue;
958 					}
959 					sep->se_rpcprog = rp->r_number;
960 				}
961 				if (sep->se_fd == -1 && !ISMUX(sep))
962 					setup(sep);
963 				if (sep->se_fd != -1)
964 					register_rpc(sep);
965 			} else
966 #endif
967 			{
968 				if (sep->se_fd >= 0)
969 					close_sep(sep);
970 				if (sep->se_fd == -1 && !ISMUX(sep))
971 					setup(sep);
972 			}
973 		    }
974 		}
975 	}
976 	endconfig();
977 	/*
978 	 * Purge anything not looked at above.
979 	 */
980 	sepp = &servtab;
981 	while ((sep = *sepp)) {
982 		if (sep->se_checked) {
983 			sepp = &sep->se_next;
984 			continue;
985 		}
986 		*sepp = sep->se_next;
987 		if (sep->se_fd >= 0)
988 			close_sep(sep);
989 		if (isrpcservice(sep))
990 			unregister_rpc(sep);
991 		if (sep->se_family == AF_LOCAL)
992 			(void)unlink(sep->se_service);
993 		if (debug)
994 			print_service("FREE", sep);
995 		freeconfig(sep);
996 		free(sep);
997 	}
998 }
999 
1000 static void
1001 retry(void)
1002 {
1003 	struct servtab *sep;
1004 
1005 	timingout = 0;
1006 	for (sep = servtab; sep != NULL; sep = sep->se_next) {
1007 		if (sep->se_fd == -1 && !ISMUX(sep)) {
1008 			switch (sep->se_family) {
1009 			case AF_LOCAL:
1010 			case AF_INET:
1011 #ifdef INET6
1012 			case AF_INET6:
1013 #endif
1014 				setup(sep);
1015 				if (sep->se_fd != -1 && isrpcservice(sep))
1016 					register_rpc(sep);
1017 				break;
1018 			}
1019 		}
1020 	}
1021 }
1022 
1023 static void
1024 goaway(void)
1025 {
1026 	struct servtab *sep;
1027 
1028 	for (sep = servtab; sep != NULL; sep = sep->se_next) {
1029 		if (sep->se_fd == -1)
1030 			continue;
1031 
1032 		switch (sep->se_family) {
1033 		case AF_LOCAL:
1034 			(void)unlink(sep->se_service);
1035 			break;
1036 		case AF_INET:
1037 #ifdef INET6
1038 		case AF_INET6:
1039 #endif
1040 			if (sep->se_wait == 1 && isrpcservice(sep))
1041 				unregister_rpc(sep);
1042 			break;
1043 		}
1044 		(void)close(sep->se_fd);
1045 	}
1046 	exit(0);
1047 }
1048 
1049 static void
1050 setup(struct servtab *sep)
1051 {
1052 	int		on = 1;
1053 #ifdef INET6
1054 	int		off = 0;
1055 #endif
1056 	struct kevent	*ev;
1057 
1058 	if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) {
1059 		if (debug)
1060 			fprintf(stderr, "socket failed on %s/%s: %s\n",
1061 			    sep->se_service, sep->se_proto, strerror(errno));
1062 		syslog(LOG_ERR, "%s/%s: socket: %m",
1063 		    sep->se_service, sep->se_proto);
1064 		return;
1065 	}
1066 	/* Set all listening sockets to close-on-exec. */
1067 	if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) {
1068 		syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m",
1069 		    sep->se_service, sep->se_proto);
1070 		close(sep->se_fd);
1071 		return;
1072 	}
1073 
1074 #define	turnon(fd, opt) \
1075 setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
1076 	if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
1077 	    turnon(sep->se_fd, SO_DEBUG) < 0)
1078 		syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
1079 	if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
1080 		syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
1081 #undef turnon
1082 
1083 	/* Set the socket buffer sizes, if specified. */
1084 	if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1085 	    SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0)
1086 		syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m",
1087 		    sep->se_sndbuf);
1088 	if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
1089 	    SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0)
1090 		syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m",
1091 		    sep->se_rcvbuf);
1092 #ifdef INET6
1093 	if (sep->se_family == AF_INET6) {
1094 		int *v;
1095 		v = (sep->se_type == FAITH_TYPE) ? &on : &off;
1096 		if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH,
1097 		    (char *)v, sizeof(*v)) < 0)
1098 			syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m");
1099 	}
1100 #endif
1101 #ifdef IPSEC
1102 	if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 &&
1103 	    sep->se_policy) {
1104 		syslog(LOG_ERR, "%s/%s: ipsec setup failed",
1105 		    sep->se_service, sep->se_proto);
1106 		(void)close(sep->se_fd);
1107 		sep->se_fd = -1;
1108 		return;
1109 	}
1110 #endif
1111 
1112 	if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) {
1113 		if (debug)
1114 			fprintf(stderr, "bind failed on %s/%s: %s\n",
1115 			    sep->se_service, sep->se_proto, strerror(errno));
1116 		syslog(LOG_ERR, "%s/%s: bind: %m",
1117 		    sep->se_service, sep->se_proto);
1118 		(void) close(sep->se_fd);
1119 		sep->se_fd = -1;
1120 		if (!timingout) {
1121 			timingout = 1;
1122 			alarm(RETRYTIME);
1123 		}
1124 		return;
1125 	}
1126 	if (sep->se_socktype == SOCK_STREAM)
1127 		listen(sep->se_fd, 10);
1128 
1129 	ev = allocchange();
1130 	EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0,
1131 	    (intptr_t)sep);
1132 	if (sep->se_fd > maxsock) {
1133 		maxsock = sep->se_fd;
1134 		if (maxsock > rlim_ofile_cur - FD_MARGIN)
1135 			bump_nofile();
1136 	}
1137 	if (debug)
1138 		fprintf(stderr, "registered %s on %d\n",
1139 		    sep->se_server, sep->se_fd);
1140 }
1141 
1142 /*
1143  * Finish with a service and its socket.
1144  */
1145 static void
1146 close_sep(struct servtab *sep)
1147 {
1148 	if (sep->se_fd >= 0) {
1149 		(void) close(sep->se_fd);
1150 		sep->se_fd = -1;
1151 	}
1152 	sep->se_count = 0;
1153 }
1154 
1155 static void
1156 register_rpc(struct servtab *sep)
1157 {
1158 #ifdef RPC
1159 	struct netbuf nbuf;
1160 	struct sockaddr_storage ss;
1161 	struct netconfig *nconf;
1162 	socklen_t socklen;
1163 	int n;
1164 
1165 	if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1166 		syslog(LOG_ERR, "%s: getnetconfigent failed",
1167 		    sep->se_proto);
1168 		return;
1169 	}
1170 	socklen = sizeof ss;
1171 	if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &socklen) < 0) {
1172 		syslog(LOG_ERR, "%s/%s: getsockname: %m",
1173 		    sep->se_service, sep->se_proto);
1174 		return;
1175 	}
1176 
1177 	nbuf.buf = &ss;
1178 	nbuf.len = ss.ss_len;
1179 	nbuf.maxlen = sizeof (struct sockaddr_storage);
1180 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1181 		if (debug)
1182 			fprintf(stderr, "rpcb_set: %u %d %s %s\n",
1183 			    sep->se_rpcprog, n, nconf->nc_netid,
1184 			    taddr2uaddr(nconf, &nbuf));
1185 		(void)rpcb_unset(sep->se_rpcprog, n, nconf);
1186 		if (!rpcb_set(sep->se_rpcprog, n, nconf, &nbuf))
1187 			syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s",
1188 			    sep->se_rpcprog, n, nconf->nc_netid,
1189 			    taddr2uaddr(nconf, &nbuf), clnt_spcreateerror(""));
1190 	}
1191 #endif /* RPC */
1192 }
1193 
1194 static void
1195 unregister_rpc(struct servtab *sep)
1196 {
1197 #ifdef RPC
1198 	int n;
1199 	struct netconfig *nconf;
1200 
1201 	if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1202 		syslog(LOG_ERR, "%s: getnetconfigent failed",
1203 		    sep->se_proto);
1204 		return;
1205 	}
1206 
1207 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1208 		if (debug)
1209 			fprintf(stderr, "rpcb_unset(%u, %d, %s)\n",
1210 			    sep->se_rpcprog, n, nconf->nc_netid);
1211 		if (!rpcb_unset(sep->se_rpcprog, n, nconf))
1212 			syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n",
1213 			    sep->se_rpcprog, n, nconf->nc_netid);
1214 	}
1215 #endif /* RPC */
1216 }
1217 
1218 
1219 static struct servtab *
1220 enter(struct servtab *cp)
1221 {
1222 	struct servtab *sep;
1223 
1224 	sep = (struct servtab *)malloc(sizeof (*sep));
1225 	if (sep == NULL) {
1226 		syslog(LOG_ERR, "Out of memory.");
1227 		exit(1);
1228 	}
1229 	*sep = *cp;
1230 	sep->se_fd = -1;
1231 	sep->se_rpcprog = -1;
1232 	sep->se_next = servtab;
1233 	servtab = sep;
1234 	return (sep);
1235 }
1236 
1237 FILE	*fconfig = NULL;
1238 struct	servtab serv;
1239 char	line[LINE_MAX];
1240 char    *defhost;
1241 #ifdef IPSEC
1242 static char *policy = NULL;
1243 #endif
1244 
1245 static int
1246 setconfig(void)
1247 {
1248 	if (defhost)
1249 		free(defhost);
1250 	defhost = newstr("*");
1251 #ifdef IPSEC
1252 	if (policy)
1253 		free(policy);
1254 	policy = NULL;
1255 #endif
1256 	if (fconfig != NULL) {
1257 		fseek(fconfig, 0L, SEEK_SET);
1258 		return (1);
1259 	}
1260 	fconfig = fopen(CONFIG, "r");
1261 	return (fconfig != NULL);
1262 }
1263 
1264 static void
1265 endconfig(void)
1266 {
1267 	if (fconfig != NULL) {
1268 		(void) fclose(fconfig);
1269 		fconfig = NULL;
1270 	}
1271 	if (defhost != NULL) {
1272 		free(defhost);
1273 		defhost = NULL;
1274 	}
1275 }
1276 
1277 static struct servtab *
1278 getconfigent(void)
1279 {
1280 	struct servtab *sep = &serv;
1281 	int argc, val;
1282 	char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
1283 	static char TCPMUX_TOKEN[] = "tcpmux/";
1284 #define MUX_LEN		(sizeof(TCPMUX_TOKEN)-1)
1285 	char *hostdelim;
1286 
1287 more:
1288 	while ((cp = nextline(fconfig))) {
1289 #ifdef IPSEC
1290 		/* lines starting with #@ is not a comment, but the policy */
1291 		if (cp[0] == '#' && cp[1] == '@') {
1292 			char *p;
1293 			for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++)
1294 				;
1295 			if (*p == '\0') {
1296 				if (policy)
1297 					free(policy);
1298 				policy = NULL;
1299 			} else {
1300 				if (ipsecsetup_test(p) < 0) {
1301 					syslog(LOG_ERR,
1302 						"%s: invalid ipsec policy \"%s\"",
1303 						CONFIG, p);
1304 					exit(1);
1305 				} else {
1306 					if (policy)
1307 						free(policy);
1308 					policy = newstr(p);
1309 				}
1310 			}
1311 		}
1312 #endif
1313 		if (*cp == '#' || *cp == '\0')
1314 			continue;
1315 #ifdef MULOG
1316 		/* Avoid use of `skip' if there is a danger of it looking
1317 		 * at continuation lines.
1318 		 */
1319 		do {
1320 			cp++;
1321 		} while (*cp == ' ' || *cp == '\t');
1322 		if (*cp == '\0')
1323 			continue;
1324 		if ((arg = skip(&cp)) == NULL)
1325 			continue;
1326 		if (strcmp(arg, "DOMAIN"))
1327 			continue;
1328 		if (curdom)
1329 			free(curdom);
1330 		curdom = NULL;
1331 		while (*cp == ' ' || *cp == '\t')
1332 			cp++;
1333 		if (*cp == '\0')
1334 			continue;
1335 		arg = cp;
1336 		while (*cp && *cp != ' ' && *cp != '\t')
1337 			cp++;
1338 		if (*cp != '\0')
1339 			*cp++ = '\0';
1340 		curdom = newstr(arg);
1341 #endif
1342 		break;
1343 	}
1344 	if (cp == NULL)
1345 		return (NULL);
1346 	/*
1347 	 * clear the static buffer, since some fields (se_ctrladdr,
1348 	 * for example) don't get initialized here.
1349 	 */
1350 	memset((caddr_t)sep, 0, sizeof *sep);
1351 	arg = skip(&cp);
1352 	if (cp == NULL) {
1353 		/* got an empty line containing just blanks/tabs. */
1354 		goto more;
1355 	}
1356 	/* Check for a host name. */
1357 	hostdelim = strrchr(arg, ':');
1358 	if (hostdelim) {
1359 		*hostdelim = '\0';
1360 		if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
1361 			hostdelim[-1] = '\0';
1362 			sep->se_hostaddr = newstr(arg + 1);
1363 		} else
1364 			sep->se_hostaddr = newstr(arg);
1365 		arg = hostdelim + 1;
1366 		/*
1367 		 * If the line is of the form `host:', then just change the
1368 		 * default host for the following lines.
1369 		 */
1370 		if (*arg == '\0') {
1371 			arg = skip(&cp);
1372 			if (cp == NULL) {
1373 				free(defhost);
1374 				defhost = sep->se_hostaddr;
1375 				goto more;
1376 			}
1377 		}
1378 	} else
1379 		sep->se_hostaddr = newstr(defhost);
1380 	if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
1381 		char *c = arg + MUX_LEN;
1382 		if (*c == '+') {
1383 			sep->se_type = MUXPLUS_TYPE;
1384 			c++;
1385 		} else
1386 			sep->se_type = MUX_TYPE;
1387 		sep->se_service = newstr(c);
1388 	} else {
1389 		sep->se_service = newstr(arg);
1390 		sep->se_type = NORM_TYPE;
1391 	}
1392 
1393 	arg = sskip(&cp);
1394 	if (strcmp(arg, "stream") == 0)
1395 		sep->se_socktype = SOCK_STREAM;
1396 	else if (strcmp(arg, "dgram") == 0)
1397 		sep->se_socktype = SOCK_DGRAM;
1398 	else if (strcmp(arg, "rdm") == 0)
1399 		sep->se_socktype = SOCK_RDM;
1400 	else if (strcmp(arg, "seqpacket") == 0)
1401 		sep->se_socktype = SOCK_SEQPACKET;
1402 	else if (strcmp(arg, "raw") == 0)
1403 		sep->se_socktype = SOCK_RAW;
1404 	else
1405 		sep->se_socktype = -1;
1406 
1407 	arg = sskip(&cp);
1408 	if (sep->se_type == NORM_TYPE &&
1409 	    strncmp(arg, "faith/", strlen("faith/")) == 0) {
1410 		arg += strlen("faith/");
1411 		sep->se_type = FAITH_TYPE;
1412 	}
1413 	sep->se_proto = newstr(arg);
1414 
1415 #define	MALFORMED(arg) \
1416 do { \
1417 	syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
1418 	    sep->se_service, (arg)); \
1419 	goto more; \
1420 } while (0)
1421 
1422 #define	GETVAL(arg) \
1423 do { \
1424 	if (!isdigit((unsigned char)*(arg))) \
1425 		MALFORMED(arg); \
1426 	val = strtol((arg), &cp0, 10); \
1427 	if (cp0 != NULL) { \
1428 		if (cp0[1] != '\0') \
1429 			MALFORMED((arg)); \
1430 		if (cp0[0] == 'k') \
1431 			val *= 1024; \
1432 		if (cp0[0] == 'm') \
1433 			val *= 1024 * 1024; \
1434 	} \
1435 	if (val < 1) { \
1436 		syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
1437 		    sep->se_service, (arg)); \
1438 		goto more; \
1439 	} \
1440 } while (0)
1441 
1442 #define	ASSIGN(arg) \
1443 do { \
1444 	if (strcmp((arg), "sndbuf") == 0) \
1445 		sep->se_sndbuf = val; \
1446 	else if (strcmp((arg), "rcvbuf") == 0) \
1447 		sep->se_rcvbuf = val; \
1448 	else \
1449 		MALFORMED((arg)); \
1450 } while (0)
1451 
1452 	/*
1453 	 * Extract the send and receive buffer sizes before parsing
1454 	 * the protocol.
1455 	 */
1456 	sep->se_sndbuf = sep->se_rcvbuf = 0;
1457 	buf0 = buf1 = sz0 = sz1 = NULL;
1458 	if ((buf0 = strchr(sep->se_proto, ',')) != NULL) {
1459 		/* Not meaningful for Tcpmux services. */
1460 		if (ISMUX(sep)) {
1461 			syslog(LOG_ERR, "%s: can't specify buffer sizes for "
1462 			    "tcpmux services", sep->se_service);
1463 			goto more;
1464 		}
1465 
1466 		/* Skip the , */
1467 		*buf0++ = '\0';
1468 
1469 		/* Check to see if another socket buffer size was specified. */
1470 		if ((buf1 = strchr(buf0, ',')) != NULL) {
1471 			/* Skip the , */
1472 			*buf1++ = '\0';
1473 
1474 			/* Make sure a 3rd one wasn't specified. */
1475 			if (strchr(buf1, ',') != NULL) {
1476 				syslog(LOG_ERR, "%s: too many buffer sizes",
1477 				    sep->se_service);
1478 				goto more;
1479 			}
1480 
1481 			/* Locate the size. */
1482 			if ((sz1 = strchr(buf1, '=')) == NULL)
1483 				MALFORMED(buf1);
1484 
1485 			/* Skip the = */
1486 			*sz1++ = '\0';
1487 		}
1488 
1489 		/* Locate the size. */
1490 		if ((sz0 = strchr(buf0, '=')) == NULL)
1491 			MALFORMED(buf0);
1492 
1493 		/* Skip the = */
1494 		*sz0++ = '\0';
1495 
1496 		GETVAL(sz0);
1497 		ASSIGN(buf0);
1498 
1499 		if (buf1 != NULL) {
1500 			GETVAL(sz1);
1501 			ASSIGN(buf1);
1502 		}
1503 	}
1504 
1505 #undef ASSIGN
1506 #undef GETVAL
1507 #undef MALFORMED
1508 
1509 	if (strcmp(sep->se_proto, "unix") == 0) {
1510 		sep->se_family = AF_LOCAL;
1511 	} else {
1512 		val = strlen(sep->se_proto);
1513 		if (!val) {
1514 			syslog(LOG_ERR, "%s: invalid protocol specified",
1515 			    sep->se_service);
1516 			goto more;
1517 		}
1518 		val = sep->se_proto[val - 1];
1519 		switch (val) {
1520 		case '4':	/*tcp4 or udp4*/
1521 			sep->se_family = AF_INET;
1522 			break;
1523 #ifdef INET6
1524 		case '6':	/*tcp6 or udp6*/
1525 			sep->se_family = AF_INET6;
1526 			break;
1527 #endif
1528 		default:
1529 			sep->se_family = AF_INET;	/*will become AF_INET6*/
1530 			break;
1531 		}
1532 		if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
1533 #ifdef RPC
1534 			char *cp, *ccp;
1535 			cp = strchr(sep->se_service, '/');
1536 			if (cp == 0) {
1537 				syslog(LOG_ERR, "%s: no rpc version",
1538 				    sep->se_service);
1539 				goto more;
1540 			}
1541 			*cp++ = '\0';
1542 			sep->se_rpcversl = sep->se_rpcversh =
1543 			    strtol(cp, &ccp, 0);
1544 			if (ccp == cp) {
1545 		badafterall:
1546 				syslog(LOG_ERR, "%s/%s: bad rpc version",
1547 				    sep->se_service, cp);
1548 				goto more;
1549 			}
1550 			if (*ccp == '-') {
1551 				cp = ccp + 1;
1552 				sep->se_rpcversh = strtol(cp, &ccp, 0);
1553 				if (ccp == cp)
1554 					goto badafterall;
1555 			}
1556 #else
1557 			syslog(LOG_ERR, "%s: rpc services not suported",
1558 			    sep->se_service);
1559 			goto more;
1560 #endif /* RPC */
1561 		}
1562 	}
1563 	arg = sskip(&cp);
1564 	{
1565 		char *cp;
1566 		if ((cp = strchr(arg, ':')) == NULL)
1567 			cp = strchr(arg, '.');
1568 		if (cp != NULL) {
1569 			*cp++ = '\0';
1570 			sep->se_max = atoi(cp);
1571 		} else
1572 			sep->se_max = TOOMANY;
1573 	}
1574 	sep->se_wait = strcmp(arg, "wait") == 0;
1575 	if (ISMUX(sep)) {
1576 		/*
1577 		 * Silently enforce "nowait" for TCPMUX services since
1578 		 * they don't have an assigned port to listen on.
1579 		 */
1580 		sep->se_wait = 0;
1581 
1582 		if (strncmp(sep->se_proto, "tcp", 3)) {
1583 			syslog(LOG_ERR,
1584 			    "%s: bad protocol for tcpmux service %s",
1585 			    CONFIG, sep->se_service);
1586 			goto more;
1587 		}
1588 		if (sep->se_socktype != SOCK_STREAM) {
1589 			syslog(LOG_ERR,
1590 			    "%s: bad socket type for tcpmux service %s",
1591 			    CONFIG, sep->se_service);
1592 			goto more;
1593 		}
1594 	}
1595 	sep->se_user = newstr(sskip(&cp));
1596 	if ((sep->se_group = strchr(sep->se_user, ':')) != NULL)
1597 		*sep->se_group++ = '\0';
1598 	else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL)
1599 		*sep->se_group++ = '\0';
1600 
1601 	sep->se_server = newstr(sskip(&cp));
1602 	if (strcmp(sep->se_server, "internal") == 0) {
1603 		struct biltin *bi;
1604 
1605 		for (bi = biltins; bi->bi_service; bi++)
1606 			if (bi->bi_socktype == sep->se_socktype &&
1607 			    strcmp(bi->bi_service, sep->se_service) == 0)
1608 				break;
1609 		if (bi->bi_service == 0) {
1610 			syslog(LOG_ERR, "internal service %s unknown",
1611 			    sep->se_service);
1612 			goto more;
1613 		}
1614 		sep->se_bi = bi;
1615 		sep->se_wait = bi->bi_wait;
1616 	} else
1617 		sep->se_bi = NULL;
1618 	argc = 0;
1619 	for (arg = skip(&cp); cp; arg = skip(&cp)) {
1620 #if MULOG
1621 		char *colon;
1622 
1623 		if (argc == 0 && (colon = strrchr(arg, ':'))) {
1624 			while (arg < colon) {
1625 				int	x;
1626 				char	*ccp;
1627 
1628 				switch (*arg++) {
1629 				case 'l':
1630 					x = 1;
1631 					if (isdigit(*arg)) {
1632 						x = strtol(arg, &ccp, 0);
1633 						if (ccp == arg)
1634 							break;
1635 						arg = ccp;
1636 					}
1637 					sep->se_log &= ~MULOG_RFC931;
1638 					sep->se_log |= x;
1639 					break;
1640 				case 'a':
1641 					sep->se_log |= MULOG_RFC931;
1642 					break;
1643 				default:
1644 					break;
1645 				}
1646 			}
1647 			arg = colon + 1;
1648 		}
1649 #endif
1650 		if (argc < MAXARGV)
1651 			sep->se_argv[argc++] = newstr(arg);
1652 	}
1653 	while (argc <= MAXARGV)
1654 		sep->se_argv[argc++] = NULL;
1655 #ifdef IPSEC
1656 	sep->se_policy = policy ? newstr(policy) : NULL;
1657 #endif
1658 	return (sep);
1659 }
1660 
1661 static void
1662 freeconfig(struct servtab *cp)
1663 {
1664 	int i;
1665 
1666 	if (cp->se_hostaddr)
1667 		free(cp->se_hostaddr);
1668 	if (cp->se_service)
1669 		free(cp->se_service);
1670 	if (cp->se_proto)
1671 		free(cp->se_proto);
1672 	if (cp->se_user)
1673 		free(cp->se_user);
1674 	/* Note: se_group is part of the newstr'ed se_user */
1675 	if (cp->se_server)
1676 		free(cp->se_server);
1677 	for (i = 0; i < MAXARGV; i++)
1678 		if (cp->se_argv[i])
1679 			free(cp->se_argv[i]);
1680 #ifdef IPSEC
1681 	if (cp->se_policy)
1682 		free(cp->se_policy);
1683 #endif
1684 }
1685 
1686 
1687 /*
1688  * Safe skip - if skip returns null, log a syntax error in the
1689  * configuration file and exit.
1690  */
1691 static char *
1692 sskip(char **cpp)
1693 {
1694 	char *cp;
1695 
1696 	cp = skip(cpp);
1697 	if (cp == NULL) {
1698 		syslog(LOG_ERR, "%s: syntax error", CONFIG);
1699 		exit(1);
1700 	}
1701 	return (cp);
1702 }
1703 
1704 static char *
1705 skip(char **cpp)
1706 {
1707 	char *cp = *cpp;
1708 	char *start;
1709 	char quote;
1710 
1711 	if (*cpp == NULL)
1712 		return (NULL);
1713 
1714 again:
1715 	while (*cp == ' ' || *cp == '\t')
1716 		cp++;
1717 	if (*cp == '\0') {
1718 		int c;
1719 
1720 		c = getc(fconfig);
1721 		(void) ungetc(c, fconfig);
1722 		if (c == ' ' || c == '\t')
1723 			if ((cp = nextline(fconfig)))
1724 				goto again;
1725 		*cpp = NULL;
1726 		return (NULL);
1727 	}
1728 	start = cp;
1729 	quote = '\0';
1730 	while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) {
1731 		if (*cp == '\'' || *cp == '"') {
1732 			if (quote && *cp != quote)
1733 				cp++;
1734 			else {
1735 				if (quote)
1736 					quote = '\0';
1737 				else
1738 					quote = *cp;
1739 				memmove(cp, cp+1, strlen(cp));
1740 			}
1741 		} else
1742 			cp++;
1743 	}
1744 	if (*cp != '\0')
1745 		*cp++ = '\0';
1746 	*cpp = cp;
1747 	return (start);
1748 }
1749 
1750 static char *
1751 nextline(FILE *fd)
1752 {
1753 	char *cp;
1754 
1755 	if (fgets(line, sizeof (line), fd) == NULL)
1756 		return (NULL);
1757 	cp = strchr(line, '\n');
1758 	if (cp)
1759 		*cp = '\0';
1760 	return (line);
1761 }
1762 
1763 static char *
1764 newstr(char *cp)
1765 {
1766 	if ((cp = strdup((cp != NULL) ? cp : "")) != NULL)
1767 		return (cp);
1768 	syslog(LOG_ERR, "strdup: %m");
1769 	exit(1);
1770 }
1771 
1772 static void
1773 inetd_setproctitle(char *a, int s)
1774 {
1775 	socklen_t size;
1776 	struct sockaddr_storage ss;
1777 	char hbuf[NI_MAXHOST], *hp;
1778 
1779 	size = sizeof(ss);
1780 	if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) {
1781 		if (getnameinfo((struct sockaddr *)&ss, size, hp = hbuf,
1782 		    sizeof(hbuf), NULL, 0, niflags) != 0)
1783 			hp = "?";
1784 		setproctitle("-%s [%s]", a, hp);
1785 	} else
1786 		setproctitle("-%s", a);
1787 }
1788 
1789 static void
1790 bump_nofile(void)
1791 {
1792 #ifdef RLIMIT_NOFILE
1793 
1794 #define FD_CHUNK	32
1795 
1796 	struct rlimit rl;
1797 
1798 	if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
1799 		syslog(LOG_ERR, "getrlimit: %m");
1800 		return;
1801 	}
1802 	rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
1803 	if (rl.rlim_cur <= rlim_ofile_cur) {
1804 		syslog(LOG_ERR,
1805 		    "bump_nofile: cannot extend file limit, max = %d",
1806 		    (int)rl.rlim_cur);
1807 		return;
1808 	}
1809 
1810 	if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
1811 		syslog(LOG_ERR, "setrlimit: %m");
1812 		return;
1813 	}
1814 
1815 	rlim_ofile_cur = rl.rlim_cur;
1816 	return;
1817 
1818 #else
1819 	syslog(LOG_ERR, "bump_nofile: cannot extend file limit");
1820 	return;
1821 #endif
1822 }
1823 
1824 /*
1825  * Internet services provided internally by inetd:
1826  */
1827 #define	BUFSIZE	4096
1828 
1829 /* ARGSUSED */
1830 static void
1831 echo_stream(int s, struct servtab *sep)	/* Echo service -- echo data back */
1832 {
1833 	char buffer[BUFSIZE];
1834 	int i;
1835 
1836 	inetd_setproctitle(sep->se_service, s);
1837 	while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
1838 	    write(s, buffer, i) > 0)
1839 		;
1840 }
1841 
1842 /* ARGSUSED */
1843 static void
1844 echo_dg(int s, struct servtab *sep)	/* Echo service -- echo data back */
1845 {
1846 	char buffer[BUFSIZE];
1847 	int i;
1848 	socklen_t size;
1849 	struct sockaddr_storage ss;
1850 	struct sockaddr *sa;
1851 
1852 	sa = (struct sockaddr *)&ss;
1853 	size = sizeof(ss);
1854 	if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0)
1855 		return;
1856 	if (port_good_dg(sa))
1857 		(void) sendto(s, buffer, i, 0, sa, size);
1858 }
1859 
1860 /* ARGSUSED */
1861 static void
1862 discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */
1863 {
1864 	char buffer[BUFSIZE];
1865 
1866 	inetd_setproctitle(sep->se_service, s);
1867 	while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
1868 			errno == EINTR)
1869 		;
1870 }
1871 
1872 /* ARGSUSED */
1873 static void
1874 discard_dg(int s, struct servtab *sep)	/* Discard service -- ignore data */
1875 
1876 {
1877 	char buffer[BUFSIZE];
1878 
1879 	(void) read(s, buffer, sizeof(buffer));
1880 }
1881 
1882 #define LINESIZ 72
1883 char ring[128];
1884 char *endring;
1885 
1886 static void
1887 initring(void)
1888 {
1889 	int i;
1890 
1891 	endring = ring;
1892 
1893 	for (i = 0; i <= 128; ++i)
1894 		if (isprint(i))
1895 			*endring++ = i;
1896 }
1897 
1898 /* ARGSUSED */
1899 static void
1900 chargen_stream(int s,struct servtab *sep)	/* Character generator */
1901 {
1902 	int len;
1903 	char *rs, text[LINESIZ+2];
1904 
1905 	inetd_setproctitle(sep->se_service, s);
1906 
1907 	if (!endring) {
1908 		initring();
1909 		rs = ring;
1910 	}
1911 
1912 	text[LINESIZ] = '\r';
1913 	text[LINESIZ + 1] = '\n';
1914 	for (rs = ring;;) {
1915 		if ((len = endring - rs) >= LINESIZ)
1916 			memmove(text, rs, LINESIZ);
1917 		else {
1918 			memmove(text, rs, len);
1919 			memmove(text + len, ring, LINESIZ - len);
1920 		}
1921 		if (++rs == endring)
1922 			rs = ring;
1923 		if (write(s, text, sizeof(text)) != sizeof(text))
1924 			break;
1925 	}
1926 }
1927 
1928 /* ARGSUSED */
1929 static void
1930 chargen_dg(int s, struct servtab *sep)		/* Character generator */
1931 {
1932 	struct sockaddr_storage ss;
1933 	struct sockaddr *sa;
1934 	static char *rs;
1935 	int len;
1936 	socklen_t size;
1937 	char text[LINESIZ+2];
1938 
1939 	if (endring == 0) {
1940 		initring();
1941 		rs = ring;
1942 	}
1943 
1944 	sa = (struct sockaddr *)&ss;
1945 	size = sizeof(ss);
1946 	if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0)
1947 		return;
1948 
1949 	if (!port_good_dg(sa))
1950 		return;
1951 
1952 	if ((len = endring - rs) >= LINESIZ)
1953 		memmove(text, rs, LINESIZ);
1954 	else {
1955 		memmove(text, rs, len);
1956 		memmove(text + len, ring, LINESIZ - len);
1957 	}
1958 	if (++rs == endring)
1959 		rs = ring;
1960 	text[LINESIZ] = '\r';
1961 	text[LINESIZ + 1] = '\n';
1962 	(void) sendto(s, text, sizeof(text), 0, sa, size);
1963 }
1964 
1965 /*
1966  * Return a machine readable date and time, in the form of the
1967  * number of seconds since midnight, Jan 1, 1900.  Since gettimeofday
1968  * returns the number of seconds since midnight, Jan 1, 1970,
1969  * we must add 2208988800 seconds to this figure to make up for
1970  * some seventy years Bell Labs was asleep.
1971  */
1972 
1973 static uint32_t
1974 machtime(void)
1975 {
1976 	struct timeval tv;
1977 
1978 	if (gettimeofday(&tv, NULL) < 0) {
1979 		if (debug)
1980 			fprintf(stderr, "Unable to get time of day\n");
1981 		return (0);
1982 	}
1983 #define	OFFSET ((uint32_t)25567 * 24*60*60)
1984 	return (htonl((uint32_t)(tv.tv_sec + OFFSET)));
1985 #undef OFFSET
1986 }
1987 
1988 /* ARGSUSED */
1989 static void
1990 machtime_stream(int s, struct servtab *sep)
1991 {
1992 	uint32_t result;
1993 
1994 	result = machtime();
1995 	(void) write(s, (char *) &result, sizeof(result));
1996 }
1997 
1998 /* ARGSUSED */
1999 void
2000 machtime_dg(int s, struct servtab *sep)
2001 {
2002 	uint32_t result;
2003 	struct sockaddr_storage ss;
2004 	struct sockaddr *sa;
2005 	socklen_t size;
2006 
2007 	sa = (struct sockaddr *)&ss;
2008 	size = sizeof(ss);
2009 	if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0)
2010 		return;
2011 	if (!port_good_dg(sa))
2012 		return;
2013 	result = machtime();
2014 	(void) sendto(s, (char *) &result, sizeof(result), 0, sa, size);
2015 }
2016 
2017 /* ARGSUSED */
2018 static void
2019 daytime_stream(int s,struct servtab *sep)
2020 /* Return human-readable time of day */
2021 {
2022 	char buffer[256];
2023 	time_t clock;
2024 	int len;
2025 
2026 	clock = time((time_t *) 0);
2027 
2028 	len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2029 	(void) write(s, buffer, len);
2030 }
2031 
2032 /* ARGSUSED */
2033 void
2034 daytime_dg(int s, struct servtab *sep)
2035 /* Return human-readable time of day */
2036 {
2037 	char buffer[256];
2038 	time_t clock;
2039 	struct sockaddr_storage ss;
2040 	struct sockaddr *sa;
2041 	socklen_t size;
2042 	int len;
2043 
2044 	clock = time((time_t *) 0);
2045 
2046 	sa = (struct sockaddr *)&ss;
2047 	size = sizeof(ss);
2048 	if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0)
2049 		return;
2050 	if (!port_good_dg(sa))
2051 		return;
2052 	len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2053 	(void) sendto(s, buffer, len, 0, sa, size);
2054 }
2055 
2056 /*
2057  * print_service:
2058  *	Dump relevant information to stderr
2059  */
2060 static void
2061 print_service(char *action, struct servtab *sep)
2062 {
2063 
2064 	if (isrpcservice(sep))
2065 		fprintf(stderr,
2066 		    "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2067 #ifdef IPSEC
2068 		    " policy=\"%s\""
2069 #endif
2070 		    "\n",
2071 		    action, sep->se_service,
2072 		    sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
2073 		    sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2074 		    (long)sep->se_bi, sep->se_server
2075 #ifdef IPSEC
2076 		    , (sep->se_policy ? sep->se_policy : "")
2077 #endif
2078 		    );
2079 	else
2080 		fprintf(stderr,
2081 		    "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2082 #ifdef IPSEC
2083 		    " policy=%s"
2084 #endif
2085 		    "\n",
2086 		    action, sep->se_service,
2087 		    sep->se_type == FAITH_TYPE ? "faith/" : "",
2088 		    sep->se_proto,
2089 		    sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2090 		    (long)sep->se_bi, sep->se_server
2091 #ifdef IPSEC
2092 		    , (sep->se_policy ? sep->se_policy : "")
2093 #endif
2094 		    );
2095 }
2096 
2097 static void
2098 usage(void)
2099 {
2100 #ifdef LIBWRAP
2101 	(void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname());
2102 #else
2103 	(void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname());
2104 #endif
2105 	exit(1);
2106 }
2107 
2108 
2109 /*
2110  *  Based on TCPMUX.C by Mark K. Lottor November 1988
2111  *  sri-nic::ps:<mkl>tcpmux.c
2112  */
2113 
2114 static int		/* # of characters upto \r,\n or \0 */
2115 getline(int fd,	char *buf, int len)
2116 {
2117 	int count = 0, n;
2118 
2119 	do {
2120 		n = read(fd, buf, len-count);
2121 		if (n == 0)
2122 			return (count);
2123 		if (n < 0)
2124 			return (-1);
2125 		while (--n >= 0) {
2126 			if (*buf == '\r' || *buf == '\n' || *buf == '\0')
2127 				return (count);
2128 			count++;
2129 			buf++;
2130 		}
2131 	} while (count < len);
2132 	return (count);
2133 }
2134 
2135 #define MAX_SERV_LEN	(256+2)		/* 2 bytes for \r\n */
2136 
2137 #define strwrite(fd, buf)	(void) write(fd, buf, sizeof(buf)-1)
2138 
2139 static void
2140 tcpmux(int ctrl, struct servtab *sep)
2141 {
2142 	char service[MAX_SERV_LEN+1];
2143 	int len;
2144 
2145 	/* Get requested service name */
2146 	if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) {
2147 		strwrite(ctrl, "-Error reading service name\r\n");
2148 		goto reject;
2149 	}
2150 	service[len] = '\0';
2151 
2152 	if (debug)
2153 		fprintf(stderr, "tcpmux: someone wants %s\n", service);
2154 
2155 	/*
2156 	 * Help is a required command, and lists available services,
2157 	 * one per line.
2158 	 */
2159 	if (!strcasecmp(service, "help")) {
2160 		strwrite(ctrl, "+Available services:\r\n");
2161 		strwrite(ctrl, "help\r\n");
2162 		for (sep = servtab; sep != NULL; sep = sep->se_next) {
2163 			if (!ISMUX(sep))
2164 				continue;
2165 			(void)write(ctrl, sep->se_service,
2166 			    strlen(sep->se_service));
2167 			strwrite(ctrl, "\r\n");
2168 		}
2169 		goto reject;
2170 	}
2171 
2172 	/* Try matching a service in inetd.conf with the request */
2173 	for (sep = servtab; sep != NULL; sep = sep->se_next) {
2174 		if (!ISMUX(sep))
2175 			continue;
2176 		if (!strcasecmp(service, sep->se_service)) {
2177 			if (ISMUXPLUS(sep))
2178 				strwrite(ctrl, "+Go\r\n");
2179 			run_service(ctrl, sep, 1 /* forked */);
2180 			return;
2181 		}
2182 	}
2183 	strwrite(ctrl, "-Service not available\r\n");
2184 reject:
2185 	_exit(1);
2186 }
2187 
2188 #ifdef MULOG
2189 void
2190 dolog(struct servtab *sep, int ctrl)
2191 {
2192 	struct sockaddr_storage	ss;
2193 	struct sockaddr		*sa = (struct sockaddr *)&ss;
2194 	socklen_t		len = sizeof(ss);
2195 	char			*host, *dp, buf[BUFSIZ];
2196 	int			connected = 1;
2197 
2198 	switch (sep->se_family) {
2199 	case AF_INET:
2200 #ifdef INET6
2201 	case AF_INET6:
2202 #endif
2203 		break;
2204 	default:
2205 		return;
2206 	}
2207 
2208 	if (getpeername(ctrl, sa, &len) < 0) {
2209 		if (errno != ENOTCONN) {
2210 			syslog(LOG_ERR, "getpeername: %m");
2211 			return;
2212 		}
2213 		if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) {
2214 			syslog(LOG_ERR, "recvfrom: %m");
2215 			return;
2216 		}
2217 		connected = 0;
2218 	}
2219 	switch (sa->sa_family) {
2220 	case AF_INET:
2221 #ifdef INET6
2222 	case AF_INET6:
2223 #endif
2224 		break;
2225 	default:
2226 		syslog(LOG_ERR, "unexpected address family %u", sa->sa_family);
2227 		return;
2228 	}
2229 
2230 	if (getnameinfo(sa, len, buf, sizeof(buf), NULL, 0, 0) != 0)
2231 		strlcpy(buf, "?", sizeof(buf));
2232 	host = buf;
2233 
2234 	switch (sep->se_log & ~MULOG_RFC931) {
2235 	case 0:
2236 		return;
2237 	case 1:
2238 		if (curdom == NULL || *curdom == '\0')
2239 			break;
2240 		dp = host + strlen(host) - strlen(curdom);
2241 		if (dp < host)
2242 			break;
2243 		if (debug)
2244 			fprintf(stderr, "check \"%s\" against curdom \"%s\"\n",
2245 			    host, curdom);
2246 		if (strcasecmp(dp, curdom) == 0)
2247 			return;
2248 		break;
2249 	case 2:
2250 	default:
2251 		break;
2252 	}
2253 
2254 	openlog("", LOG_NOWAIT, MULOG);
2255 
2256 	if (connected && (sep->se_log & MULOG_RFC931))
2257 		syslog(LOG_INFO, "%s@%s wants %s",
2258 		    rfc931_name(sa, ctrl), host, sep->se_service);
2259 	else
2260 		syslog(LOG_INFO, "%s wants %s",
2261 		    host, sep->se_service);
2262 }
2263 
2264 /*
2265  * From tcp_log by
2266  *  Wietse Venema, Eindhoven University of Technology, The Netherlands.
2267  */
2268 #if 0
2269 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46";
2270 #endif
2271 
2272 #include <setjmp.h>
2273 
2274 #define	RFC931_PORT	113		/* Semi-well-known port */
2275 #define	TIMEOUT		4
2276 #define	TIMEOUT2	10
2277 
2278 static jmp_buf timebuf;
2279 
2280 /* timeout - handle timeouts */
2281 
2282 static void
2283 timeout(int sig)
2284 {
2285 	longjmp(timebuf, sig);
2286 }
2287 
2288 /* rfc931_name - return remote user name */
2289 
2290 char *
2291 rfc931_name(struct sockaddr *there,	/* remote link information */
2292     int ctrl)
2293 {
2294 	struct sockaddr_storage here;	/* local link information */
2295 	struct sockaddr_storage sin;	/* for talking to RFC931 daemon */
2296 	socklen_t	length;
2297 	int		s;
2298 	unsigned	remote;
2299 	unsigned	local;
2300 	static char	user[256];		/* XXX */
2301 	char		buf[256];
2302 	char		*cp;
2303 	char		*result = "USER_UNKNOWN";
2304 	int		len;
2305 	u_int16_t	myport, hisport;
2306 
2307 	/* Find out local port number of our stdin. */
2308 
2309 	length = sizeof(here);
2310 	if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) {
2311 		syslog(LOG_ERR, "getsockname: %m");
2312 		return (result);
2313 	}
2314 	switch (here.ss_family) {
2315 	case AF_INET:
2316 		myport = ((struct sockaddr_in *)&here)->sin_port;
2317 		break;
2318 #ifdef INET6
2319 	case AF_INET6:
2320 		myport = ((struct sockaddr_in6 *)&here)->sin6_port;
2321 		break;
2322 #endif
2323 	}
2324 	switch (there->sa_family) {
2325 	case AF_INET:
2326 		hisport = ((struct sockaddr_in *)&there)->sin_port;
2327 		break;
2328 #ifdef INET6
2329 	case AF_INET6:
2330 		hisport = ((struct sockaddr_in6 *)&there)->sin6_port;
2331 		break;
2332 #endif
2333 	}
2334 	/* Set up timer so we won't get stuck. */
2335 
2336 	if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) {
2337 		syslog(LOG_ERR, "socket: %m");
2338 		return (result);
2339 	}
2340 
2341 	sin = here;
2342 	switch (sin.ss_family) {
2343 	case AF_INET:
2344 		((struct sockaddr_in *)&sin)->sin_port = htons(0);
2345 		break;
2346 #ifdef INET6
2347 	case AF_INET6:
2348 		((struct sockaddr_in6 *)&sin)->sin6_port = htons(0);
2349 		break;
2350 #endif
2351 	}
2352 	if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2353 		syslog(LOG_ERR, "bind: %m");
2354 		return (result);
2355 	}
2356 
2357 	signal(SIGALRM, timeout);
2358 	if (setjmp(timebuf)) {
2359 		close(s);			/* not: fclose(fp) */
2360 		return (result);
2361 	}
2362 	alarm(TIMEOUT);
2363 
2364 	/* Connect to the RFC931 daemon. */
2365 
2366 	memcpy(&sin, there, there->sa_len);
2367 	switch (sin.ss_family) {
2368 	case AF_INET:
2369 		((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT);
2370 		break;
2371 #ifdef INET6
2372 	case AF_INET6:
2373 		((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT);
2374 		break;
2375 #endif
2376 	}
2377 	if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2378 		close(s);
2379 		alarm(0);
2380 		return (result);
2381 	}
2382 
2383 	/* Query the RFC 931 server. Would 13-byte writes ever be broken up? */
2384 	(void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport),
2385 	    ntohs(myport));
2386 
2387 	for (len = 0, cp = buf; len < strlen(buf); ) {
2388 		int	n;
2389 
2390 		if ((n = write(s, cp, strlen(buf) - len)) == -1) {
2391 			close(s);
2392 			alarm(0);
2393 			return (result);
2394 		}
2395 		cp += n;
2396 		len += n;
2397 	}
2398 
2399 	/* Read response */
2400 	for (cp = buf; cp < buf + sizeof(buf) - 1; ) {
2401 		char	c;
2402 		if (read(s, &c, 1) != 1) {
2403 			close(s);
2404 			alarm(0);
2405 			return (result);
2406 		}
2407 		if (c == '\n')
2408 			break;
2409 		*cp++ = c;
2410 	}
2411 	*cp = '\0';
2412 
2413 	if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local,
2414 	    user) == 3 && ntohs(hisport) == remote && ntohs(myport) == local) {
2415 		/* Strip trailing carriage return. */
2416 		if ((cp = strchr(user, '\r')) != NULL)
2417 			*cp = 0;
2418 		result = user;
2419 	}
2420 
2421 	alarm(0);
2422 	close(s);
2423 	return (result);
2424 }
2425 #endif
2426 
2427 /*
2428  * check if the address/port where send data to is one of the obvious ports
2429  * that are used for denial of service attacks like two echo ports
2430  * just echoing data between them
2431  */
2432 static int
2433 port_good_dg(struct sockaddr *sa)
2434 {
2435 	struct in_addr in;
2436 #ifdef INET6
2437 	struct in6_addr *in6;
2438 #endif
2439 	u_int16_t port;
2440 	int i, bad;
2441 	char hbuf[NI_MAXHOST];
2442 
2443 	bad = 0;
2444 
2445 	switch (sa->sa_family) {
2446 	case AF_INET:
2447 		in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
2448 		port = ntohs(((struct sockaddr_in *)sa)->sin_port);
2449 #ifdef INET6
2450 	v4chk:
2451 #endif
2452 		if (IN_MULTICAST(in.s_addr))
2453 			goto bad;
2454 		switch ((in.s_addr & 0xff000000) >> 24) {
2455 		case 0: case 127: case 255:
2456 			goto bad;
2457 		}
2458 		if (dg_broadcast(&in))
2459 			goto bad;
2460 		break;
2461 #ifdef INET6
2462 	case AF_INET6:
2463 		in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
2464 		port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
2465 		if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
2466 			goto bad;
2467 		if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
2468 			memcpy(&in, &in6->s6_addr[12], sizeof(in));
2469 			in.s_addr = ntohl(in.s_addr);
2470 			goto v4chk;
2471 		}
2472 		break;
2473 #endif
2474 	default:
2475 		/* XXX unsupported af, is it safe to assume it to be safe? */
2476 		return (1);
2477 	}
2478 
2479 	for (i = 0; bad_ports[i] != 0; i++) {
2480 		if (port == bad_ports[i])
2481 			goto bad;
2482 	}
2483 
2484 	return (1);
2485 
2486 bad:
2487 	if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0,
2488 	    niflags) != 0)
2489 		strlcpy(hbuf, "?", sizeof(hbuf));
2490 	syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d",
2491 		hbuf, port);
2492 	return (0);
2493 }
2494 
2495 /* XXX need optimization */
2496 static int
2497 dg_broadcast(struct in_addr *in)
2498 {
2499 	struct ifaddrs *ifa, *ifap;
2500 	struct sockaddr_in *sin;
2501 
2502 	if (getifaddrs(&ifap) < 0)
2503 		return (0);
2504 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
2505 		if (ifa->ifa_addr->sa_family != AF_INET ||
2506 		    (ifa->ifa_flags & IFF_BROADCAST) == 0)
2507 			continue;
2508 		sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
2509 		if (sin->sin_addr.s_addr == in->s_addr) {
2510 			freeifaddrs(ifap);
2511 			return (1);
2512 		}
2513 	}
2514 	freeifaddrs(ifap);
2515 	return (0);
2516 }
2517 
2518 static int
2519 my_kevent(const struct kevent *changelist, size_t nchanges,
2520     struct kevent *eventlist, size_t nevents)
2521 {
2522 	int	result;
2523 
2524 	while ((result = kevent(kq, changelist, nchanges, eventlist, nevents,
2525 	    NULL)) < 0)
2526 		if (errno != EINTR) {
2527 			syslog(LOG_ERR, "kevent: %m");
2528 			exit(EXIT_FAILURE);
2529 		}
2530 
2531 	return (result);
2532 }
2533 
2534 static struct kevent *
2535 allocchange(void)
2536 {
2537 	if (changes == A_CNT(changebuf)) {
2538 		(void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0);
2539 		changes = 0;
2540 	}
2541 
2542 	return (&changebuf[changes++]);
2543 }
2544