xref: /netbsd-src/usr.sbin/inetd/inetd.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: inetd.c,v 1.98 2004/10/29 21:27:34 dsl 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  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the NetBSD
22  *	Foundation, Inc. and its contributors.
23  * 4. Neither the name of The NetBSD Foundation nor the names of its
24  *    contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  */
39 
40 /*
41  * Copyright (c) 1983, 1991, 1993, 1994
42  *	The Regents of the University of California.  All rights reserved.
43  *
44  * Redistribution and use in source and binary forms, with or without
45  * modification, are permitted provided that the following conditions
46  * are met:
47  * 1. Redistributions of source code must retain the above copyright
48  *    notice, this list of conditions and the following disclaimer.
49  * 2. Redistributions in binary form must reproduce the above copyright
50  *    notice, this list of conditions and the following disclaimer in the
51  *    documentation and/or other materials provided with the distribution.
52  * 3. 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, 1991, 1993, 1994\n\
72 	The Regents of the University of California.  All rights reserved.\n");
73 #if 0
74 static char sccsid[] = "@(#)inetd.c	8.4 (Berkeley) 4/13/94";
75 #else
76 __RCSID("$NetBSD: inetd.c,v 1.98 2004/10/29 21:27:34 dsl Exp $");
77 #endif
78 #endif /* not lint */
79 
80 /*
81  * Inetd - Internet super-server
82  *
83  * This program invokes all internet services as needed.  Connection-oriented
84  * services are invoked each time a connection is made, by creating a process.
85  * This process is passed the connection as file descriptor 0 and is expected
86  * to do a getpeername to find out the source host and port.
87  *
88  * Datagram oriented services are invoked when a datagram
89  * arrives; a process is created and passed a pending message
90  * on file descriptor 0.  Datagram servers may either connect
91  * to their peer, freeing up the original socket for inetd
92  * to receive further messages on, or ``take over the socket'',
93  * processing all arriving datagrams and, eventually, timing
94  * out.	 The first type of server is said to be ``multi-threaded'';
95  * the second type of server ``single-threaded''.
96  *
97  * Inetd uses a configuration file which is read at startup
98  * and, possibly, at some later time in response to a hangup signal.
99  * The configuration file is ``free format'' with fields given in the
100  * order shown below.  Continuation lines for an entry must being with
101  * a space or tab.  All fields must be present in each entry.
102  *
103  *	service name			must be in /etc/services or must
104  *					name a tcpmux service
105  *	socket type			stream/dgram/raw/rdm/seqpacket
106  *	protocol			must be in /etc/protocols
107  *	wait/nowait[:max]		single-threaded/multi-threaded, max #
108  *	user[:group]			user/group to run daemon as
109  *	server program			full path name
110  *	server program arguments	maximum of MAXARGS (20)
111  *
112  * For RPC services
113  *      service name/version            must be in /etc/rpc
114  *	socket type			stream/dgram/raw/rdm/seqpacket
115  *	protocol			must be in /etc/protocols
116  *	wait/nowait[:max]		single-threaded/multi-threaded
117  *	user[:group]			user to run daemon as
118  *	server program			full path name
119  *	server program arguments	maximum of MAXARGS (20)
120  *
121  * For non-RPC services, the "service name" can be of the form
122  * hostaddress:servicename, in which case the hostaddress is used
123  * as the host portion of the address to listen on.  If hostaddress
124  * consists of a single `*' character, INADDR_ANY is used.
125  *
126  * A line can also consist of just
127  *	hostaddress:
128  * where hostaddress is as in the preceding paragraph.  Such a line must
129  * have no further fields; the specified hostaddress is remembered and
130  * used for all further lines that have no hostaddress specified,
131  * until the next such line (or EOF).  (This is why * is provided to
132  * allow explicit specification of INADDR_ANY.)  A line
133  *	*:
134  * is implicitly in effect at the beginning of the file.
135  *
136  * The hostaddress specifier may (and often will) contain dots;
137  * the service name must not.
138  *
139  * For RPC services, host-address specifiers are accepted and will
140  * work to some extent; however, because of limitations in the
141  * portmapper interface, it will not work to try to give more than
142  * one line for any given RPC service, even if the host-address
143  * specifiers are different.
144  *
145  * TCP services without official port numbers are handled with the
146  * RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
147  * requests. When a connection is made from a foreign host, the service
148  * requested is passed to tcpmux, which looks it up in the servtab list
149  * and returns the proper entry for the service. Tcpmux returns a
150  * negative reply if the service doesn't exist, otherwise the invoked
151  * server is expected to return the positive reply if the service type in
152  * inetd.conf file has the prefix "tcpmux/". If the service type has the
153  * prefix "tcpmux/+", tcpmux will return the positive reply for the
154  * process; this is for compatibility with older server code, and also
155  * allows you to invoke programs that use stdin/stdout without putting any
156  * special server code in them. Services that use tcpmux are "nowait"
157  * because they do not have a well-known port and hence cannot listen
158  * for new requests.
159  *
160  * Comment lines are indicated by a `#' in column 1.
161  *
162  * #ifdef IPSEC
163  * Comment lines that start with "#@" denote IPsec policy string, as described
164  * in ipsec_set_policy(3).  This will affect all the following items in
165  * inetd.conf(8).  To reset the policy, just use "#@" line.  By default,
166  * there's no IPsec policy.
167  * #endif
168  */
169 
170 /*
171  * Here's the scoop concerning the user:group feature:
172  *
173  * 1) set-group-option off.
174  *
175  * 	a) user = root:	NO setuid() or setgid() is done
176  *
177  * 	b) other:	setuid()
178  * 			setgid(primary group as found in passwd)
179  * 			initgroups(name, primary group)
180  *
181  * 2) set-group-option on.
182  *
183  * 	a) user = root:	NO setuid()
184  * 			setgid(specified group)
185  * 			NO initgroups()
186  *
187  * 	b) other:	setuid()
188  * 			setgid(specified group)
189  * 			initgroups(name, specified group)
190  *
191  */
192 
193 #include <sys/param.h>
194 #include <sys/stat.h>
195 #include <sys/ioctl.h>
196 #include <sys/socket.h>
197 #include <sys/un.h>
198 #include <sys/wait.h>
199 #include <sys/time.h>
200 #include <sys/resource.h>
201 #include <sys/event.h>
202 
203 #ifndef RLIMIT_NOFILE
204 #define RLIMIT_NOFILE	RLIMIT_OFILE
205 #endif
206 
207 #ifndef NO_RPC
208 #define RPC
209 #endif
210 
211 #include <net/if.h>
212 
213 #include <netinet/in.h>
214 #include <arpa/inet.h>
215 #ifdef RPC
216 #include <rpc/rpc.h>
217 #include <rpc/rpcb_clnt.h>
218 #include <netconfig.h>
219 #endif
220 
221 #include <ctype.h>
222 #include <errno.h>
223 #include <fcntl.h>
224 #include <grp.h>
225 #include <netdb.h>
226 #include <pwd.h>
227 #include <signal.h>
228 #include <stdio.h>
229 #include <stdlib.h>
230 #include <string.h>
231 #include <syslog.h>
232 #include <unistd.h>
233 #include <util.h>
234 #include <ifaddrs.h>
235 
236 #include "pathnames.h"
237 
238 #ifdef IPSEC
239 #include <netinet6/ipsec.h>
240 #ifndef IPSEC_POLICY_IPSEC	/* no ipsec support on old ipsec */
241 #undef IPSEC
242 #endif
243 #include "ipsec.h"
244 #endif
245 
246 #ifdef LIBWRAP
247 # include <tcpd.h>
248 #ifndef LIBWRAP_ALLOW_FACILITY
249 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH
250 #endif
251 #ifndef LIBWRAP_ALLOW_SEVERITY
252 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO
253 #endif
254 #ifndef LIBWRAP_DENY_FACILITY
255 # define LIBWRAP_DENY_FACILITY LOG_AUTH
256 #endif
257 #ifndef LIBWRAP_DENY_SEVERITY
258 # define LIBWRAP_DENY_SEVERITY LOG_WARNING
259 #endif
260 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
261 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
262 #endif
263 
264 #define	TOOMANY		40		/* don't start more than TOOMANY */
265 #define	CNT_INTVL	60		/* servers in CNT_INTVL sec. */
266 #define	RETRYTIME	(60*10)		/* retry after bind or server fail */
267 
268 #define	A_CNT(a)	(sizeof (a) / sizeof (a[0]))
269 
270 int	debug;
271 #ifdef LIBWRAP
272 int	lflag;
273 #endif
274 int	maxsock;
275 int	kq;
276 int	options;
277 int	timingout;
278 struct	servent *sp;
279 char	*curdom;
280 const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
281 
282 #ifndef OPEN_MAX
283 #define OPEN_MAX	64
284 #endif
285 
286 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
287 #define FD_MARGIN	(8)
288 rlim_t		rlim_ofile_cur = OPEN_MAX;
289 
290 #ifdef RLIMIT_NOFILE
291 struct rlimit	rlim_ofile;
292 #endif
293 
294 struct kevent	changebuf[64];
295 size_t		changes;
296 
297 struct	servtab {
298 	char	*se_hostaddr;		/* host address to listen on */
299 	char	*se_service;		/* name of service */
300 	int	se_socktype;		/* type of socket to use */
301 	int	se_family;		/* address family */
302 	char	*se_proto;		/* protocol used */
303 	int	se_sndbuf;		/* sndbuf size */
304 	int	se_rcvbuf;		/* rcvbuf size */
305 	int	se_rpcprog;		/* rpc program number */
306 	int	se_rpcversl;		/* rpc program lowest version */
307 	int	se_rpcversh;		/* rpc program highest version */
308 #define isrpcservice(sep)	((sep)->se_rpcversl != 0)
309 	pid_t	se_wait;		/* single threaded server */
310 	short	se_checked;		/* looked at during merge */
311 	char	*se_user;		/* user name to run as */
312 	char	*se_group;		/* group name to run as */
313 	struct	biltin *se_bi;		/* if built-in, description */
314 	char	*se_server;		/* server program */
315 #define	MAXARGV 20
316 	char	*se_argv[MAXARGV+1];	/* program arguments */
317 #ifdef IPSEC
318 	char	*se_policy;		/* IPsec poilcy string */
319 #endif
320 	int	se_fd;			/* open descriptor */
321 	int	se_type;		/* type */
322 	union {
323 		struct	sockaddr se_un_ctrladdr;
324 		struct	sockaddr_in se_un_ctrladdr_in;
325 		struct	sockaddr_in6 se_un_ctrladdr_in6;
326 		struct	sockaddr_un se_un_ctrladdr_un;
327 	} se_un;			/* bound address */
328 #define se_ctrladdr	se_un.se_un_ctrladdr
329 #define se_ctrladdr_in	se_un.se_un_ctrladdr_in
330 #define se_ctrladdr_un	se_un.se_un_ctrladdr_un
331 	int	se_ctrladdr_size;
332 	int	se_max;			/* max # of instances of this service */
333 	int	se_count;		/* number started since se_time */
334 	struct	timeval se_time;	/* start of se_count */
335 #ifdef MULOG
336 	int	se_log;
337 #define MULOG_RFC931	0x40000000
338 #endif
339 	struct	servtab *se_next;
340 } *servtab;
341 
342 #define NORM_TYPE	0
343 #define MUX_TYPE	1
344 #define MUXPLUS_TYPE	2
345 #define FAITH_TYPE	3
346 #define ISMUX(sep)	(((sep)->se_type == MUX_TYPE) || \
347 			 ((sep)->se_type == MUXPLUS_TYPE))
348 #define ISMUXPLUS(sep)	((sep)->se_type == MUXPLUS_TYPE)
349 
350 
351 static void	chargen_dg(int, struct servtab *);
352 static void	chargen_stream(int, struct servtab *);
353 static void	close_sep(struct servtab *);
354 static void	config(void);
355 static void	daytime_dg(int, struct servtab *);
356 static void	daytime_stream(int, struct servtab *);
357 static void	discard_dg(int, struct servtab *);
358 static void	discard_stream(int, struct servtab *);
359 static void	echo_dg(int, struct servtab *);
360 static void	echo_stream(int, struct servtab *);
361 static void	endconfig(void);
362 static struct servtab *enter(struct servtab *);
363 static void	freeconfig(struct servtab *);
364 static struct servtab *getconfigent(void);
365 static void	goaway(void);
366 static void	machtime_dg(int, struct servtab *);
367 static void	machtime_stream(int, struct servtab *);
368 static char    *newstr(char *);
369 static char    *nextline(FILE *);
370 static void	print_service(char *, struct servtab *);
371 static void	reapchild(void);
372 static void	retry(void);
373 static void	run_service(int, struct servtab *);
374 static int	setconfig(void);
375 static void	setup(struct servtab *);
376 static char    *sskip(char **);
377 static char    *skip(char **);
378 static void	tcpmux(int, struct servtab *);
379 static void	usage(void);
380 static void	register_rpc(struct servtab *);
381 static void	unregister_rpc(struct servtab *);
382 static void	bump_nofile(void);
383 static void	inetd_setproctitle(char *, int);
384 static void	initring(void);
385 static uint32_t	machtime(void);
386 static int	port_good_dg(struct sockaddr *);
387 static int 	dg_broadcast(struct in_addr *);
388 static int	my_kevent(const struct kevent *, size_t, struct kevent *,
389 		size_t);
390 static struct kevent *	allocchange(void);
391 static int	getline(int, char *, int);
392 static void	spawn(struct servtab *, int);
393 #ifdef MULOG
394 static void	dolog(struct servtab *, int);
395 static void	timeout(int);
396 static char    *rfc931_name(struct sockaddr *, int);
397 #endif
398 
399 struct biltin {
400 	char	*bi_service;		/* internally provided service name */
401 	int	bi_socktype;		/* type of socket supported */
402 	short	bi_fork;		/* 1 if should fork before call */
403 	short	bi_wait;		/* 1 if should wait for child */
404 	void	(*bi_fn)(int, struct servtab *);
405 					/* function which performs it */
406 } biltins[] = {
407 	/* Echo received data */
408 	{ "echo",	SOCK_STREAM,	1, 0,	echo_stream },
409 	{ "echo",	SOCK_DGRAM,	0, 0,	echo_dg },
410 
411 	/* Internet /dev/null */
412 	{ "discard",	SOCK_STREAM,	1, 0,	discard_stream },
413 	{ "discard",	SOCK_DGRAM,	0, 0,	discard_dg },
414 
415 	/* Return 32 bit time since 1970 */
416 	{ "time",	SOCK_STREAM,	0, 0,	machtime_stream },
417 	{ "time",	SOCK_DGRAM,	0, 0,	machtime_dg },
418 
419 	/* Return human-readable time */
420 	{ "daytime",	SOCK_STREAM,	0, 0,	daytime_stream },
421 	{ "daytime",	SOCK_DGRAM,	0, 0,	daytime_dg },
422 
423 	/* Familiar character generator */
424 	{ "chargen",	SOCK_STREAM,	1, 0,	chargen_stream },
425 	{ "chargen",	SOCK_DGRAM,	0, 0,	chargen_dg },
426 
427 	{ "tcpmux",	SOCK_STREAM,	1, 0,	tcpmux },
428 
429 	{ NULL }
430 };
431 
432 /* list of "bad" ports. I.e. ports that are most obviously used for
433  * "cycling packets" denial of service attacks. See /etc/services.
434  * List must end with port number "0".
435  */
436 
437 u_int16_t bad_ports[] =  { 7, 9, 13, 19, 37, 0 };
438 
439 
440 #define NUMINT	(sizeof(intab) / sizeof(struct inent))
441 char	*CONFIG = _PATH_INETDCONF;
442 
443 static int my_signals[] =
444     { SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE };
445 
446 int
447 main(int argc, char *argv[])
448 {
449 	int		ch, n, reload = 1;
450 
451 	while ((ch = getopt(argc, argv,
452 #ifdef LIBWRAP
453 					"dl"
454 #else
455 					"d"
456 #endif
457 					   )) != -1)
458 		switch(ch) {
459 		case 'd':
460 			debug = 1;
461 			options |= SO_DEBUG;
462 			break;
463 #ifdef LIBWRAP
464 		case 'l':
465 			lflag = 1;
466 			break;
467 #endif
468 		case '?':
469 		default:
470 			usage();
471 		}
472 	argc -= optind;
473 	argv += optind;
474 
475 	if (argc > 0)
476 		CONFIG = argv[0];
477 
478 	if (!debug)
479 		daemon(0, 0);
480 	openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
481 	pidfile(NULL);
482 
483 	kq = kqueue();
484 	if (kq < 0) {
485 		syslog(LOG_ERR, "kqueue: %m");
486 		return (EXIT_FAILURE);
487 	}
488 
489 #ifdef RLIMIT_NOFILE
490 	if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
491 		syslog(LOG_ERR, "getrlimit: %m");
492 	} else {
493 		rlim_ofile_cur = rlim_ofile.rlim_cur;
494 		if (rlim_ofile_cur == RLIM_INFINITY)	/* ! */
495 			rlim_ofile_cur = OPEN_MAX;
496 	}
497 #endif
498 
499 	for (n = 0; n < A_CNT(my_signals); n++) {
500 		int	signum;
501 
502 		signum = my_signals[n];
503 		(void) signal(signum, SIG_IGN);
504 
505 		if (signum != SIGPIPE) {
506 			struct kevent	*ev;
507 
508 			ev = allocchange();
509 			EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
510 			    0, 0, 0);
511 		}
512 	}
513 
514 	for (;;) {
515 		int		ctrl;
516 		struct kevent	eventbuf[64], *ev;
517 		struct servtab	*sep;
518 
519 		if (reload) {
520 			reload = 0;
521 			config();
522 		}
523 
524 		n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf));
525 		changes = 0;
526 
527 		for (ev = eventbuf; n > 0; ev++, n--) {
528 			if (ev->filter == EVFILT_SIGNAL) {
529 				switch (ev->ident) {
530 				case SIGALRM:
531 					retry();
532 					break;
533 				case SIGCHLD:
534 					reapchild();
535 					break;
536 				case SIGTERM:
537 				case SIGINT:
538 					goaway();
539 					break;
540 				case SIGHUP:
541 					reload = 1;
542 					break;
543 				}
544 				continue;
545 			}
546 			if (ev->filter != EVFILT_READ)
547 				continue;
548 			sep = (struct servtab *)ev->udata;
549 			/* Paranoia */
550 			if (ev->ident != sep->se_fd)
551 				continue;
552 			if (debug)
553 				fprintf(stderr, "someone wants %s\n",
554 				    sep->se_service);
555 			if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
556 				/* XXX here do the libwrap check-before-accept*/
557 				ctrl = accept(sep->se_fd, NULL, NULL);
558 				if (debug)
559 					fprintf(stderr, "accept, ctrl %d\n",
560 					    ctrl);
561 				if (ctrl < 0) {
562 					if (errno != EINTR)
563 						syslog(LOG_WARNING,
564 						    "accept (for %s): %m",
565 						    sep->se_service);
566 					continue;
567 				}
568 			} else
569 				ctrl = sep->se_fd;
570 			spawn(sep, ctrl);
571 		}
572 	}
573 }
574 
575 static void
576 spawn(struct servtab *sep, int ctrl)
577 {
578 	int dofork;
579 	pid_t pid;
580 
581 	pid = 0;
582 #ifdef LIBWRAP_INTERNAL
583 	dofork = 1;
584 #else
585 	dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
586 #endif
587 	if (dofork) {
588 		if (sep->se_count++ == 0)
589 			(void)gettimeofday(&sep->se_time, NULL);
590 		else if (sep->se_count >= sep->se_max) {
591 			struct timeval now;
592 
593 			(void)gettimeofday(&now, NULL);
594 			if (now.tv_sec - sep->se_time.tv_sec > CNT_INTVL) {
595 				sep->se_time = now;
596 				sep->se_count = 1;
597 			} else {
598 				syslog(LOG_ERR,
599 				    "%s/%s max spawn rate (%d in %d seconds) "
600 				    "exceeded; service not started",
601 				    sep->se_service, sep->se_proto,
602 				    sep->se_max, CNT_INTVL);
603 				if (!sep->se_wait && sep->se_socktype ==
604 				    SOCK_STREAM)
605 					close(ctrl);
606 				close_sep(sep);
607 				if (!timingout) {
608 					timingout = 1;
609 					alarm(RETRYTIME);
610 				}
611 				return;
612 			}
613 		}
614 		pid = fork();
615 		if (pid < 0) {
616 			syslog(LOG_ERR, "fork: %m");
617 			if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
618 				close(ctrl);
619 			sleep(1);
620 			return;
621 		}
622 		if (pid != 0 && sep->se_wait) {
623 			struct kevent	*ev;
624 
625 			sep->se_wait = pid;
626 			ev = allocchange();
627 			EV_SET(ev, sep->se_fd, EVFILT_READ,
628 			    EV_DELETE, 0, 0, 0);
629 		}
630 		if (pid == 0) {
631 			int	n;
632 
633 			for (n = 0; n < A_CNT(my_signals); n++)
634 				(void) signal(my_signals[n], SIG_DFL);
635 			if (debug)
636 				setsid();
637 		}
638 	}
639 	if (pid == 0) {
640 		run_service(ctrl, sep);
641 		if (dofork)
642 			exit(0);
643 	}
644 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
645 		close(ctrl);
646 }
647 
648 static void
649 run_service(int ctrl, struct servtab *sep)
650 {
651 	struct passwd *pwd;
652 	struct group *grp = NULL;	/* XXX gcc */
653 	char buf[NI_MAXSERV];
654 #ifdef LIBWRAP
655 	struct request_info req;
656 	int denied;
657 	char *service = NULL;	/* XXX gcc */
658 #endif
659 
660 #ifdef LIBWRAP
661 #ifndef LIBWRAP_INTERNAL
662 	if (sep->se_bi == 0)
663 #endif
664 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
665 		request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
666 		    sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
667 		fromhost(&req);
668 		denied = !hosts_access(&req);
669 		if (denied || lflag) {
670 			if (getnameinfo(&sep->se_ctrladdr,
671 					sep->se_ctrladdr.sa_len, NULL, 0,
672 					buf, sizeof(buf), 0) != 0) {
673 				/* shouldn't happen */
674 				(void)snprintf(buf, sizeof buf, "%d",
675 				    ntohs(sep->se_ctrladdr_in.sin_port));
676 			}
677 			service = buf;
678 		}
679 		if (denied) {
680 			syslog(deny_severity,
681 			    "refused connection from %.500s, service %s (%s)",
682 			    eval_client(&req), service, sep->se_proto);
683 			goto reject;
684 		}
685 		if (lflag) {
686 			syslog(allow_severity,
687 			    "connection from %.500s, service %s (%s)",
688 			    eval_client(&req), service, sep->se_proto);
689 		}
690 	}
691 #endif /* LIBWRAP */
692 
693 	if (sep->se_bi) {
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 	int 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=(type)a; (type)a=(type)b; (type)b=(type)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 	int n;
1160 	struct netbuf nbuf;
1161 	struct sockaddr_storage ss;
1162 	struct netconfig *nconf;
1163 
1164 	if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1165 		syslog(LOG_ERR, "%s: getnetconfigent failed",
1166 		    sep->se_proto);
1167 		return;
1168 	}
1169 	n = sizeof ss;
1170 	if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &n) < 0) {
1171 		syslog(LOG_ERR, "%s/%s: getsockname: %m",
1172 		    sep->se_service, sep->se_proto);
1173 		return;
1174 	}
1175 
1176 	nbuf.buf = &ss;
1177 	nbuf.len = ss.ss_len;
1178 	nbuf.maxlen = sizeof (struct sockaddr_storage);
1179 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1180 		if (debug)
1181 			fprintf(stderr, "rpcb_set: %u %d %s %s\n",
1182 			    sep->se_rpcprog, n, nconf->nc_netid,
1183 			    taddr2uaddr(nconf, &nbuf));
1184 		(void)rpcb_unset(sep->se_rpcprog, n, nconf);
1185 		if (!rpcb_set(sep->se_rpcprog, n, nconf, &nbuf))
1186 			syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s",
1187 			    sep->se_rpcprog, n, nconf->nc_netid,
1188 			    taddr2uaddr(nconf, &nbuf), clnt_spcreateerror(""));
1189 	}
1190 #endif /* RPC */
1191 }
1192 
1193 static void
1194 unregister_rpc(struct servtab *sep)
1195 {
1196 #ifdef RPC
1197 	int n;
1198 	struct netconfig *nconf;
1199 
1200 	if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
1201 		syslog(LOG_ERR, "%s: getnetconfigent failed",
1202 		    sep->se_proto);
1203 		return;
1204 	}
1205 
1206 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
1207 		if (debug)
1208 			fprintf(stderr, "rpcb_unset(%u, %d, %s)\n",
1209 			    sep->se_rpcprog, n, nconf->nc_netid);
1210 		if (!rpcb_unset(sep->se_rpcprog, n, nconf))
1211 			syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n",
1212 			    sep->se_rpcprog, n, nconf->nc_netid);
1213 	}
1214 #endif /* RPC */
1215 }
1216 
1217 
1218 static struct servtab *
1219 enter(struct servtab *cp)
1220 {
1221 	struct servtab *sep;
1222 
1223 	sep = (struct servtab *)malloc(sizeof (*sep));
1224 	if (sep == NULL) {
1225 		syslog(LOG_ERR, "Out of memory.");
1226 		exit(1);
1227 	}
1228 	*sep = *cp;
1229 	sep->se_fd = -1;
1230 	sep->se_rpcprog = -1;
1231 	sep->se_next = servtab;
1232 	servtab = sep;
1233 	return (sep);
1234 }
1235 
1236 FILE	*fconfig = NULL;
1237 struct	servtab serv;
1238 char	line[LINE_MAX];
1239 char    *defhost;
1240 #ifdef IPSEC
1241 static char *policy = NULL;
1242 #endif
1243 
1244 static int
1245 setconfig(void)
1246 {
1247 	if (defhost)
1248 		free(defhost);
1249 	defhost = newstr("*");
1250 #ifdef IPSEC
1251 	if (policy)
1252 		free(policy);
1253 	policy = NULL;
1254 #endif
1255 	if (fconfig != NULL) {
1256 		fseek(fconfig, 0L, SEEK_SET);
1257 		return (1);
1258 	}
1259 	fconfig = fopen(CONFIG, "r");
1260 	return (fconfig != NULL);
1261 }
1262 
1263 static void
1264 endconfig(void)
1265 {
1266 	if (fconfig != NULL) {
1267 		(void) fclose(fconfig);
1268 		fconfig = NULL;
1269 	}
1270 	if (defhost != NULL) {
1271 		free(defhost);
1272 		defhost = NULL;
1273 	}
1274 }
1275 
1276 static struct servtab *
1277 getconfigent(void)
1278 {
1279 	struct servtab *sep = &serv;
1280 	int argc, val;
1281 	char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
1282 	static char TCPMUX_TOKEN[] = "tcpmux/";
1283 #define MUX_LEN		(sizeof(TCPMUX_TOKEN)-1)
1284 	char *hostdelim;
1285 
1286 more:
1287 	while ((cp = nextline(fconfig))) {
1288 #ifdef IPSEC
1289 		/* lines starting with #@ is not a comment, but the policy */
1290 		if (cp[0] == '#' && cp[1] == '@') {
1291 			char *p;
1292 			for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++)
1293 				;
1294 			if (*p == '\0') {
1295 				if (policy)
1296 					free(policy);
1297 				policy = NULL;
1298 			} else {
1299 				if (ipsecsetup_test(p) < 0) {
1300 					syslog(LOG_ERR,
1301 						"%s: invalid ipsec policy \"%s\"",
1302 						CONFIG, p);
1303 					exit(1);
1304 				} else {
1305 					if (policy)
1306 						free(policy);
1307 					policy = newstr(p);
1308 				}
1309 			}
1310 		}
1311 #endif
1312 		if (*cp == '#' || *cp == '\0')
1313 			continue;
1314 #ifdef MULOG
1315 		/* Avoid use of `skip' if there is a danger of it looking
1316 		 * at continuation lines.
1317 		 */
1318 		do {
1319 			cp++;
1320 		} while (*cp == ' ' || *cp == '\t');
1321 		if (*cp == '\0')
1322 			continue;
1323 		if ((arg = skip(&cp)) == NULL)
1324 			continue;
1325 		if (strcmp(arg, "DOMAIN"))
1326 			continue;
1327 		if (curdom)
1328 			free(curdom);
1329 		curdom = NULL;
1330 		while (*cp == ' ' || *cp == '\t')
1331 			cp++;
1332 		if (*cp == '\0')
1333 			continue;
1334 		arg = cp;
1335 		while (*cp && *cp != ' ' && *cp != '\t')
1336 			cp++;
1337 		if (*cp != '\0')
1338 			*cp++ = '\0';
1339 		curdom = newstr(arg);
1340 #endif
1341 		break;
1342 	}
1343 	if (cp == NULL)
1344 		return (NULL);
1345 	/*
1346 	 * clear the static buffer, since some fields (se_ctrladdr,
1347 	 * for example) don't get initialized here.
1348 	 */
1349 	memset((caddr_t)sep, 0, sizeof *sep);
1350 	arg = skip(&cp);
1351 	if (cp == NULL) {
1352 		/* got an empty line containing just blanks/tabs. */
1353 		goto more;
1354 	}
1355 	/* Check for a host name. */
1356 	hostdelim = strrchr(arg, ':');
1357 	if (hostdelim) {
1358 		*hostdelim = '\0';
1359 		if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
1360 			hostdelim[-1] = '\0';
1361 			sep->se_hostaddr = newstr(arg + 1);
1362 		} else
1363 			sep->se_hostaddr = newstr(arg);
1364 		arg = hostdelim + 1;
1365 		/*
1366 		 * If the line is of the form `host:', then just change the
1367 		 * default host for the following lines.
1368 		 */
1369 		if (*arg == '\0') {
1370 			arg = skip(&cp);
1371 			if (cp == NULL) {
1372 				free(defhost);
1373 				defhost = sep->se_hostaddr;
1374 				goto more;
1375 			}
1376 		}
1377 	} else
1378 		sep->se_hostaddr = newstr(defhost);
1379 	if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
1380 		char *c = arg + MUX_LEN;
1381 		if (*c == '+') {
1382 			sep->se_type = MUXPLUS_TYPE;
1383 			c++;
1384 		} else
1385 			sep->se_type = MUX_TYPE;
1386 		sep->se_service = newstr(c);
1387 	} else {
1388 		sep->se_service = newstr(arg);
1389 		sep->se_type = NORM_TYPE;
1390 	}
1391 
1392 	arg = sskip(&cp);
1393 	if (strcmp(arg, "stream") == 0)
1394 		sep->se_socktype = SOCK_STREAM;
1395 	else if (strcmp(arg, "dgram") == 0)
1396 		sep->se_socktype = SOCK_DGRAM;
1397 	else if (strcmp(arg, "rdm") == 0)
1398 		sep->se_socktype = SOCK_RDM;
1399 	else if (strcmp(arg, "seqpacket") == 0)
1400 		sep->se_socktype = SOCK_SEQPACKET;
1401 	else if (strcmp(arg, "raw") == 0)
1402 		sep->se_socktype = SOCK_RAW;
1403 	else
1404 		sep->se_socktype = -1;
1405 
1406 	arg = sskip(&cp);
1407 	if (sep->se_type == NORM_TYPE &&
1408 	    strncmp(arg, "faith/", strlen("faith/")) == 0) {
1409 		arg += strlen("faith/");
1410 		sep->se_type = FAITH_TYPE;
1411 	}
1412 	sep->se_proto = newstr(arg);
1413 
1414 #define	MALFORMED(arg) \
1415 do { \
1416 	syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
1417 	    sep->se_service, (arg)); \
1418 	goto more; \
1419 } while (0)
1420 
1421 #define	GETVAL(arg) \
1422 do { \
1423 	if (!isdigit((unsigned char)*(arg))) \
1424 		MALFORMED(arg); \
1425 	val = strtol((arg), &cp0, 10); \
1426 	if (cp0 != NULL) { \
1427 		if (cp0[1] != '\0') \
1428 			MALFORMED((arg)); \
1429 		if (cp0[0] == 'k') \
1430 			val *= 1024; \
1431 		if (cp0[0] == 'm') \
1432 			val *= 1024 * 1024; \
1433 	} \
1434 	if (val < 1) { \
1435 		syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
1436 		    sep->se_service, (arg)); \
1437 		goto more; \
1438 	} \
1439 } while (0)
1440 
1441 #define	ASSIGN(arg) \
1442 do { \
1443 	if (strcmp((arg), "sndbuf") == 0) \
1444 		sep->se_sndbuf = val; \
1445 	else if (strcmp((arg), "rcvbuf") == 0) \
1446 		sep->se_rcvbuf = val; \
1447 	else \
1448 		MALFORMED((arg)); \
1449 } while (0)
1450 
1451 	/*
1452 	 * Extract the send and receive buffer sizes before parsing
1453 	 * the protocol.
1454 	 */
1455 	sep->se_sndbuf = sep->se_rcvbuf = 0;
1456 	buf0 = buf1 = sz0 = sz1 = NULL;
1457 	if ((buf0 = strchr(sep->se_proto, ',')) != NULL) {
1458 		/* Not meaningful for Tcpmux services. */
1459 		if (ISMUX(sep)) {
1460 			syslog(LOG_ERR, "%s: can't specify buffer sizes for "
1461 			    "tcpmux services", sep->se_service);
1462 			goto more;
1463 		}
1464 
1465 		/* Skip the , */
1466 		*buf0++ = '\0';
1467 
1468 		/* Check to see if another socket buffer size was specified. */
1469 		if ((buf1 = strchr(buf0, ',')) != NULL) {
1470 			/* Skip the , */
1471 			*buf1++ = '\0';
1472 
1473 			/* Make sure a 3rd one wasn't specified. */
1474 			if (strchr(buf1, ',') != NULL) {
1475 				syslog(LOG_ERR, "%s: too many buffer sizes",
1476 				    sep->se_service);
1477 				goto more;
1478 			}
1479 
1480 			/* Locate the size. */
1481 			if ((sz1 = strchr(buf1, '=')) == NULL)
1482 				MALFORMED(buf1);
1483 
1484 			/* Skip the = */
1485 			*sz1++ = '\0';
1486 		}
1487 
1488 		/* Locate the size. */
1489 		if ((sz0 = strchr(buf0, '=')) == NULL)
1490 			MALFORMED(buf0);
1491 
1492 		/* Skip the = */
1493 		*sz0++ = '\0';
1494 
1495 		GETVAL(sz0);
1496 		ASSIGN(buf0);
1497 
1498 		if (buf1 != NULL) {
1499 			GETVAL(sz1);
1500 			ASSIGN(buf1);
1501 		}
1502 	}
1503 
1504 #undef ASSIGN
1505 #undef GETVAL
1506 #undef MALFORMED
1507 
1508 	if (strcmp(sep->se_proto, "unix") == 0) {
1509 		sep->se_family = AF_LOCAL;
1510 	} else {
1511 		val = strlen(sep->se_proto);
1512 		if (!val) {
1513 			syslog(LOG_ERR, "%s: invalid protocol specified",
1514 			    sep->se_service);
1515 			goto more;
1516 		}
1517 		val = sep->se_proto[val - 1];
1518 		switch (val) {
1519 		case '4':	/*tcp4 or udp4*/
1520 			sep->se_family = AF_INET;
1521 			break;
1522 #ifdef INET6
1523 		case '6':	/*tcp6 or udp6*/
1524 			sep->se_family = AF_INET6;
1525 			break;
1526 #endif
1527 		default:
1528 			sep->se_family = AF_INET;	/*will become AF_INET6*/
1529 			break;
1530 		}
1531 		if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
1532 #ifdef RPC
1533 			char *cp, *ccp;
1534 			cp = strchr(sep->se_service, '/');
1535 			if (cp == 0) {
1536 				syslog(LOG_ERR, "%s: no rpc version",
1537 				    sep->se_service);
1538 				goto more;
1539 			}
1540 			*cp++ = '\0';
1541 			sep->se_rpcversl = sep->se_rpcversh =
1542 			    strtol(cp, &ccp, 0);
1543 			if (ccp == cp) {
1544 		badafterall:
1545 				syslog(LOG_ERR, "%s/%s: bad rpc version",
1546 				    sep->se_service, cp);
1547 				goto more;
1548 			}
1549 			if (*ccp == '-') {
1550 				cp = ccp + 1;
1551 				sep->se_rpcversh = strtol(cp, &ccp, 0);
1552 				if (ccp == cp)
1553 					goto badafterall;
1554 			}
1555 #else
1556 			syslog(LOG_ERR, "%s: rpc services not suported",
1557 			    sep->se_service);
1558 			goto more;
1559 #endif /* RPC */
1560 		}
1561 	}
1562 	arg = sskip(&cp);
1563 	{
1564 		char *cp;
1565 		if ((cp = strchr(arg, ':')) == NULL)
1566 			cp = strchr(arg, '.');
1567 		if (cp != NULL) {
1568 			*cp++ = '\0';
1569 			sep->se_max = atoi(cp);
1570 		} else
1571 			sep->se_max = TOOMANY;
1572 	}
1573 	sep->se_wait = strcmp(arg, "wait") == 0;
1574 	if (ISMUX(sep)) {
1575 		/*
1576 		 * Silently enforce "nowait" for TCPMUX services since
1577 		 * they don't have an assigned port to listen on.
1578 		 */
1579 		sep->se_wait = 0;
1580 
1581 		if (strncmp(sep->se_proto, "tcp", 3)) {
1582 			syslog(LOG_ERR,
1583 			    "%s: bad protocol for tcpmux service %s",
1584 			    CONFIG, sep->se_service);
1585 			goto more;
1586 		}
1587 		if (sep->se_socktype != SOCK_STREAM) {
1588 			syslog(LOG_ERR,
1589 			    "%s: bad socket type for tcpmux service %s",
1590 			    CONFIG, sep->se_service);
1591 			goto more;
1592 		}
1593 	}
1594 	sep->se_user = newstr(sskip(&cp));
1595 	if ((sep->se_group = strchr(sep->se_user, ':')) != NULL)
1596 		*sep->se_group++ = '\0';
1597 	else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL)
1598 		*sep->se_group++ = '\0';
1599 
1600 	sep->se_server = newstr(sskip(&cp));
1601 	if (strcmp(sep->se_server, "internal") == 0) {
1602 		struct biltin *bi;
1603 
1604 		for (bi = biltins; bi->bi_service; bi++)
1605 			if (bi->bi_socktype == sep->se_socktype &&
1606 			    strcmp(bi->bi_service, sep->se_service) == 0)
1607 				break;
1608 		if (bi->bi_service == 0) {
1609 			syslog(LOG_ERR, "internal service %s unknown",
1610 			    sep->se_service);
1611 			goto more;
1612 		}
1613 		sep->se_bi = bi;
1614 		sep->se_wait = bi->bi_wait;
1615 	} else
1616 		sep->se_bi = NULL;
1617 	argc = 0;
1618 	for (arg = skip(&cp); cp; arg = skip(&cp)) {
1619 #if MULOG
1620 		char *colon;
1621 
1622 		if (argc == 0 && (colon = strrchr(arg, ':'))) {
1623 			while (arg < colon) {
1624 				int	x;
1625 				char	*ccp;
1626 
1627 				switch (*arg++) {
1628 				case 'l':
1629 					x = 1;
1630 					if (isdigit(*arg)) {
1631 						x = strtol(arg, &ccp, 0);
1632 						if (ccp == arg)
1633 							break;
1634 						arg = ccp;
1635 					}
1636 					sep->se_log &= ~MULOG_RFC931;
1637 					sep->se_log |= x;
1638 					break;
1639 				case 'a':
1640 					sep->se_log |= MULOG_RFC931;
1641 					break;
1642 				default:
1643 					break;
1644 				}
1645 			}
1646 			arg = colon + 1;
1647 		}
1648 #endif
1649 		if (argc < MAXARGV)
1650 			sep->se_argv[argc++] = newstr(arg);
1651 	}
1652 	while (argc <= MAXARGV)
1653 		sep->se_argv[argc++] = NULL;
1654 #ifdef IPSEC
1655 	sep->se_policy = policy ? newstr(policy) : NULL;
1656 #endif
1657 	return (sep);
1658 }
1659 
1660 static void
1661 freeconfig(struct servtab *cp)
1662 {
1663 	int i;
1664 
1665 	if (cp->se_hostaddr)
1666 		free(cp->se_hostaddr);
1667 	if (cp->se_service)
1668 		free(cp->se_service);
1669 	if (cp->se_proto)
1670 		free(cp->se_proto);
1671 	if (cp->se_user)
1672 		free(cp->se_user);
1673 	/* Note: se_group is part of the newstr'ed se_user */
1674 	if (cp->se_server)
1675 		free(cp->se_server);
1676 	for (i = 0; i < MAXARGV; i++)
1677 		if (cp->se_argv[i])
1678 			free(cp->se_argv[i]);
1679 #ifdef IPSEC
1680 	if (cp->se_policy)
1681 		free(cp->se_policy);
1682 #endif
1683 }
1684 
1685 
1686 /*
1687  * Safe skip - if skip returns null, log a syntax error in the
1688  * configuration file and exit.
1689  */
1690 static char *
1691 sskip(char **cpp)
1692 {
1693 	char *cp;
1694 
1695 	cp = skip(cpp);
1696 	if (cp == NULL) {
1697 		syslog(LOG_ERR, "%s: syntax error", CONFIG);
1698 		exit(1);
1699 	}
1700 	return (cp);
1701 }
1702 
1703 static char *
1704 skip(char **cpp)
1705 {
1706 	char *cp = *cpp;
1707 	char *start;
1708 	char quote;
1709 
1710 	if (*cpp == NULL)
1711 		return (NULL);
1712 
1713 again:
1714 	while (*cp == ' ' || *cp == '\t')
1715 		cp++;
1716 	if (*cp == '\0') {
1717 		int c;
1718 
1719 		c = getc(fconfig);
1720 		(void) ungetc(c, fconfig);
1721 		if (c == ' ' || c == '\t')
1722 			if ((cp = nextline(fconfig)))
1723 				goto again;
1724 		*cpp = NULL;
1725 		return (NULL);
1726 	}
1727 	start = cp;
1728 	quote = '\0';
1729 	while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) {
1730 		if (*cp == '\'' || *cp == '"') {
1731 			if (quote && *cp != quote)
1732 				cp++;
1733 			else {
1734 				if (quote)
1735 					quote = '\0';
1736 				else
1737 					quote = *cp;
1738 				memmove(cp, cp+1, strlen(cp));
1739 			}
1740 		} else
1741 			cp++;
1742 	}
1743 	if (*cp != '\0')
1744 		*cp++ = '\0';
1745 	*cpp = cp;
1746 	return (start);
1747 }
1748 
1749 static char *
1750 nextline(FILE *fd)
1751 {
1752 	char *cp;
1753 
1754 	if (fgets(line, sizeof (line), fd) == NULL)
1755 		return (NULL);
1756 	cp = strchr(line, '\n');
1757 	if (cp)
1758 		*cp = '\0';
1759 	return (line);
1760 }
1761 
1762 static char *
1763 newstr(char *cp)
1764 {
1765 	if ((cp = strdup((cp !=NULL )? cp : "")) != NULL)
1766 		return (cp);
1767 	syslog(LOG_ERR, "strdup: %m");
1768 	exit(1);
1769 }
1770 
1771 static void
1772 inetd_setproctitle(char *a, int s)
1773 {
1774 	socklen_t size;
1775 	struct sockaddr_storage ss;
1776 	char hbuf[NI_MAXHOST];
1777 
1778 	size = sizeof(ss);
1779 	if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) {
1780 		if (getnameinfo((struct sockaddr *)&ss, size, hbuf,
1781 		    sizeof(hbuf), NULL, 0, niflags) == 0)
1782 			setproctitle("-%s [%s]", a, hbuf);
1783 		else
1784 			setproctitle("-%s [?]", a);
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 #include <ctype.h>
1883 #define LINESIZ 72
1884 char ring[128];
1885 char *endring;
1886 
1887 static void
1888 initring(void)
1889 {
1890 	int i;
1891 
1892 	endring = ring;
1893 
1894 	for (i = 0; i <= 128; ++i)
1895 		if (isprint(i))
1896 			*endring++ = i;
1897 }
1898 
1899 /* ARGSUSED */
1900 static void
1901 chargen_stream(int s,struct servtab *sep)	/* Character generator */
1902 {
1903 	int len;
1904 	char *rs, text[LINESIZ+2];
1905 
1906 	inetd_setproctitle(sep->se_service, s);
1907 
1908 	if (!endring) {
1909 		initring();
1910 		rs = ring;
1911 	}
1912 
1913 	text[LINESIZ] = '\r';
1914 	text[LINESIZ + 1] = '\n';
1915 	for (rs = ring;;) {
1916 		if ((len = endring - rs) >= LINESIZ)
1917 			memmove(text, rs, LINESIZ);
1918 		else {
1919 			memmove(text, rs, len);
1920 			memmove(text + len, ring, LINESIZ - len);
1921 		}
1922 		if (++rs == endring)
1923 			rs = ring;
1924 		if (write(s, text, sizeof(text)) != sizeof(text))
1925 			break;
1926 	}
1927 }
1928 
1929 /* ARGSUSED */
1930 static void
1931 chargen_dg(int s, struct servtab *sep)		/* Character generator */
1932 {
1933 	struct sockaddr_storage ss;
1934 	struct sockaddr *sa;
1935 	static char *rs;
1936 	int len;
1937 	socklen_t size;
1938 	char text[LINESIZ+2];
1939 
1940 	if (endring == 0) {
1941 		initring();
1942 		rs = ring;
1943 	}
1944 
1945 	sa = (struct sockaddr *)&ss;
1946 	size = sizeof(ss);
1947 	if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0)
1948 		return;
1949 
1950 	if (!port_good_dg(sa))
1951 		return;
1952 
1953 	if ((len = endring - rs) >= LINESIZ)
1954 		memmove(text, rs, LINESIZ);
1955 	else {
1956 		memmove(text, rs, len);
1957 		memmove(text + len, ring, LINESIZ - len);
1958 	}
1959 	if (++rs == endring)
1960 		rs = ring;
1961 	text[LINESIZ] = '\r';
1962 	text[LINESIZ + 1] = '\n';
1963 	(void) sendto(s, text, sizeof(text), 0, sa, size);
1964 }
1965 
1966 /*
1967  * Return a machine readable date and time, in the form of the
1968  * number of seconds since midnight, Jan 1, 1900.  Since gettimeofday
1969  * returns the number of seconds since midnight, Jan 1, 1970,
1970  * we must add 2208988800 seconds to this figure to make up for
1971  * some seventy years Bell Labs was asleep.
1972  */
1973 
1974 static uint32_t
1975 machtime(void)
1976 {
1977 	struct timeval tv;
1978 
1979 	if (gettimeofday(&tv, NULL) < 0) {
1980 		if (debug)
1981 			fprintf(stderr, "Unable to get time of day\n");
1982 		return (0);
1983 	}
1984 #define	OFFSET ((uint32_t)25567 * 24*60*60)
1985 	return (htonl((uint32_t)(tv.tv_sec + OFFSET)));
1986 #undef OFFSET
1987 }
1988 
1989 /* ARGSUSED */
1990 static void
1991 machtime_stream(int s, struct servtab *sep)
1992 {
1993 	uint32_t result;
1994 
1995 	result = machtime();
1996 	(void) write(s, (char *) &result, sizeof(result));
1997 }
1998 
1999 /* ARGSUSED */
2000 void
2001 machtime_dg(int s, struct servtab *sep)
2002 {
2003 	uint32_t result;
2004 	struct sockaddr_storage ss;
2005 	struct sockaddr *sa;
2006 	socklen_t size;
2007 
2008 	sa = (struct sockaddr *)&ss;
2009 	size = sizeof(ss);
2010 	if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0)
2011 		return;
2012 	if (!port_good_dg(sa))
2013 		return;
2014 	result = machtime();
2015 	(void) sendto(s, (char *) &result, sizeof(result), 0, sa, size);
2016 }
2017 
2018 /* ARGSUSED */
2019 static void
2020 daytime_stream(int s,struct servtab *sep)
2021 /* Return human-readable time of day */
2022 {
2023 	char buffer[256];
2024 	time_t clock;
2025 	int len;
2026 
2027 	clock = time((time_t *) 0);
2028 
2029 	len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2030 	(void) write(s, buffer, len);
2031 }
2032 
2033 /* ARGSUSED */
2034 void
2035 daytime_dg(int s, struct servtab *sep)
2036 /* Return human-readable time of day */
2037 {
2038 	char buffer[256];
2039 	time_t clock;
2040 	struct sockaddr_storage ss;
2041 	struct sockaddr *sa;
2042 	socklen_t size;
2043 	int len;
2044 
2045 	clock = time((time_t *) 0);
2046 
2047 	sa = (struct sockaddr *)&ss;
2048 	size = sizeof(ss);
2049 	if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0)
2050 		return;
2051 	if (!port_good_dg(sa))
2052 		return;
2053 	len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
2054 	(void) sendto(s, buffer, len, 0, sa, size);
2055 }
2056 
2057 /*
2058  * print_service:
2059  *	Dump relevant information to stderr
2060  */
2061 static void
2062 print_service(char *action, struct servtab *sep)
2063 {
2064 
2065 	if (isrpcservice(sep))
2066 		fprintf(stderr,
2067 		    "%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2068 #ifdef IPSEC
2069 		    " policy=\"%s\""
2070 #endif
2071 		    "\n",
2072 		    action, sep->se_service,
2073 		    sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
2074 		    sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2075 		    (long)sep->se_bi, sep->se_server
2076 #ifdef IPSEC
2077 		    , (sep->se_policy ? sep->se_policy : "")
2078 #endif
2079 		    );
2080 	else
2081 		fprintf(stderr,
2082 		    "%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
2083 #ifdef IPSEC
2084 		    " policy=%s"
2085 #endif
2086 		    "\n",
2087 		    action, sep->se_service,
2088 		    sep->se_type == FAITH_TYPE ? "faith/" : "",
2089 		    sep->se_proto,
2090 		    sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
2091 		    (long)sep->se_bi, sep->se_server
2092 #ifdef IPSEC
2093 		    , (sep->se_policy ? sep->se_policy : "")
2094 #endif
2095 		    );
2096 }
2097 
2098 static void
2099 usage(void)
2100 {
2101 #ifdef LIBWRAP
2102 	(void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname());
2103 #else
2104 	(void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname());
2105 #endif
2106 	exit(1);
2107 }
2108 
2109 
2110 /*
2111  *  Based on TCPMUX.C by Mark K. Lottor November 1988
2112  *  sri-nic::ps:<mkl>tcpmux.c
2113  */
2114 
2115 static int		/* # of characters upto \r,\n or \0 */
2116 getline(int fd,	char *buf, int len)
2117 {
2118 	int count = 0, n;
2119 
2120 	do {
2121 		n = read(fd, buf, len-count);
2122 		if (n == 0)
2123 			return (count);
2124 		if (n < 0)
2125 			return (-1);
2126 		while (--n >= 0) {
2127 			if (*buf == '\r' || *buf == '\n' || *buf == '\0')
2128 				return (count);
2129 			count++;
2130 			buf++;
2131 		}
2132 	} while (count < len);
2133 	return (count);
2134 }
2135 
2136 #define MAX_SERV_LEN	(256+2)		/* 2 bytes for \r\n */
2137 
2138 #define strwrite(fd, buf)	(void) write(fd, buf, sizeof(buf)-1)
2139 
2140 static void
2141 tcpmux(int ctrl, struct servtab *sep)
2142 {
2143 	char service[MAX_SERV_LEN+1];
2144 	int len;
2145 
2146 	/* Get requested service name */
2147 	if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) {
2148 		strwrite(ctrl, "-Error reading service name\r\n");
2149 		goto reject;
2150 	}
2151 	service[len] = '\0';
2152 
2153 	if (debug)
2154 		fprintf(stderr, "tcpmux: someone wants %s\n", service);
2155 
2156 	/*
2157 	 * Help is a required command, and lists available services,
2158 	 * one per line.
2159 	 */
2160 	if (!strcasecmp(service, "help")) {
2161 		strwrite(ctrl, "+Available services:\r\n");
2162 		strwrite(ctrl, "help\r\n");
2163 		for (sep = servtab; sep != NULL; sep = sep->se_next) {
2164 			if (!ISMUX(sep))
2165 				continue;
2166 			(void)write(ctrl, sep->se_service,
2167 			    strlen(sep->se_service));
2168 			strwrite(ctrl, "\r\n");
2169 		}
2170 		goto reject;
2171 	}
2172 
2173 	/* Try matching a service in inetd.conf with the request */
2174 	for (sep = servtab; sep != NULL; sep = sep->se_next) {
2175 		if (!ISMUX(sep))
2176 			continue;
2177 		if (!strcasecmp(service, sep->se_service)) {
2178 			if (ISMUXPLUS(sep))
2179 				strwrite(ctrl, "+Go\r\n");
2180 			run_service(ctrl, sep);
2181 			return;
2182 		}
2183 	}
2184 	strwrite(ctrl, "-Service not available\r\n");
2185 reject:
2186 	_exit(1);
2187 }
2188 
2189 #ifdef MULOG
2190 void
2191 dolog(struct servtab *sep, int ctrl)
2192 {
2193 	struct sockaddr_storage	ss;
2194 	struct sockaddr		*sa = (struct sockaddr *)&ss;
2195 	socklen_t		len = sizeof(ss);
2196 	char			*host, *dp, buf[BUFSIZ];
2197 	int			connected = 1;
2198 
2199 	switch (sep->se_family) {
2200 	case AF_INET:
2201 #ifdef INET6
2202 	case AF_INET6:
2203 #endif
2204 		break;
2205 	default:
2206 		return;
2207 	}
2208 
2209 	if (getpeername(ctrl, sa, &len) < 0) {
2210 		if (errno != ENOTCONN) {
2211 			syslog(LOG_ERR, "getpeername: %m");
2212 			return;
2213 		}
2214 		if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) {
2215 			syslog(LOG_ERR, "recvfrom: %m");
2216 			return;
2217 		}
2218 		connected = 0;
2219 	}
2220 	switch (sa->sa_family) {
2221 	case AF_INET:
2222 #ifdef INET6
2223 	case AF_INET6:
2224 #endif
2225 		break;
2226 	default:
2227 		syslog(LOG_ERR, "unexpected address family %u", sa->sa_family);
2228 		return;
2229 	}
2230 
2231 	if (getnameinfo(sa, len, buf, sizeof(buf), NULL, 0, 0) != 0)
2232 		strlcpy(buf, "?", sizeof(buf));
2233 	host = buf;
2234 
2235 	switch (sep->se_log & ~MULOG_RFC931) {
2236 	case 0:
2237 		return;
2238 	case 1:
2239 		if (curdom == NULL || *curdom == '\0')
2240 			break;
2241 		dp = host + strlen(host) - strlen(curdom);
2242 		if (dp < host)
2243 			break;
2244 		if (debug)
2245 			fprintf(stderr, "check \"%s\" against curdom \"%s\"\n",
2246 			    host, curdom);
2247 		if (strcasecmp(dp, curdom) == 0)
2248 			return;
2249 		break;
2250 	case 2:
2251 	default:
2252 		break;
2253 	}
2254 
2255 	openlog("", LOG_NOWAIT, MULOG);
2256 
2257 	if (connected && (sep->se_log & MULOG_RFC931))
2258 		syslog(LOG_INFO, "%s@%s wants %s",
2259 		    rfc931_name(sa, ctrl), host, sep->se_service);
2260 	else
2261 		syslog(LOG_INFO, "%s wants %s",
2262 		    host, sep->se_service);
2263 }
2264 
2265 /*
2266  * From tcp_log by
2267  *  Wietse Venema, Eindhoven University of Technology, The Netherlands.
2268  */
2269 #if 0
2270 static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46";
2271 #endif
2272 
2273 #include <setjmp.h>
2274 
2275 #define	RFC931_PORT	113		/* Semi-well-known port */
2276 #define	TIMEOUT		4
2277 #define	TIMEOUT2	10
2278 
2279 static jmp_buf timebuf;
2280 
2281 /* timeout - handle timeouts */
2282 
2283 static void
2284 timeout(int sig)
2285 {
2286 	longjmp(timebuf, sig);
2287 }
2288 
2289 /* rfc931_name - return remote user name */
2290 
2291 char *
2292 rfc931_name(struct sockaddr *there,	/* remote link information */
2293     int ctrl)
2294 {
2295 	struct sockaddr_storage here;	/* local link information */
2296 	struct sockaddr_storage sin;	/* for talking to RFC931 daemon */
2297 	socklen_t	length;
2298 	int		s;
2299 	unsigned	remote;
2300 	unsigned	local;
2301 	static char	user[256];		/* XXX */
2302 	char		buf[256];
2303 	char		*cp;
2304 	char		*result = "USER_UNKNOWN";
2305 	int		len;
2306 	u_int16_t	myport, hisport;
2307 
2308 	/* Find out local port number of our stdin. */
2309 
2310 	length = sizeof(here);
2311 	if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) {
2312 		syslog(LOG_ERR, "getsockname: %m");
2313 		return (result);
2314 	}
2315 	switch (here.ss_family) {
2316 	case AF_INET:
2317 		myport = ((struct sockaddr_in *)&here)->sin_port;
2318 		break;
2319 #ifdef INET6
2320 	case AF_INET6:
2321 		myport = ((struct sockaddr_in6 *)&here)->sin6_port;
2322 		break;
2323 #endif
2324 	}
2325 	switch (there->sa_family) {
2326 	case AF_INET:
2327 		hisport = ((struct sockaddr_in *)&there)->sin_port;
2328 		break;
2329 #ifdef INET6
2330 	case AF_INET6:
2331 		hisport = ((struct sockaddr_in6 *)&there)->sin6_port;
2332 		break;
2333 #endif
2334 	}
2335 	/* Set up timer so we won't get stuck. */
2336 
2337 	if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) {
2338 		syslog(LOG_ERR, "socket: %m");
2339 		return (result);
2340 	}
2341 
2342 	sin = here;
2343 	switch (sin.ss_family) {
2344 	case AF_INET:
2345 		((struct sockaddr_in *)&sin)->sin_port = htons(0);
2346 		break;
2347 #ifdef INET6
2348 	case AF_INET6:
2349 		((struct sockaddr_in6 *)&sin)->sin6_port = htons(0);
2350 		break;
2351 #endif
2352 	}
2353 	if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2354 		syslog(LOG_ERR, "bind: %m");
2355 		return (result);
2356 	}
2357 
2358 	signal(SIGALRM, timeout);
2359 	if (setjmp(timebuf)) {
2360 		close(s);			/* not: fclose(fp) */
2361 		return (result);
2362 	}
2363 	alarm(TIMEOUT);
2364 
2365 	/* Connect to the RFC931 daemon. */
2366 
2367 	memcpy(&sin, there, there->sa_len);
2368 	switch (sin.ss_family) {
2369 	case AF_INET:
2370 		((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT);
2371 		break;
2372 #ifdef INET6
2373 	case AF_INET6:
2374 		((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT);
2375 		break;
2376 #endif
2377 	}
2378 	if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
2379 		close(s);
2380 		alarm(0);
2381 		return (result);
2382 	}
2383 
2384 	/* Query the RFC 931 server. Would 13-byte writes ever be broken up? */
2385 	(void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport),
2386 	    ntohs(myport));
2387 
2388 	for (len = 0, cp = buf; len < strlen(buf); ) {
2389 		int	n;
2390 
2391 		if ((n = write(s, cp, strlen(buf) - len)) == -1) {
2392 			close(s);
2393 			alarm(0);
2394 			return (result);
2395 		}
2396 		cp += n;
2397 		len += n;
2398 	}
2399 
2400 	/* Read response */
2401 	for (cp = buf; cp < buf + sizeof(buf) - 1; ) {
2402 		char	c;
2403 		if (read(s, &c, 1) != 1) {
2404 			close(s);
2405 			alarm(0);
2406 			return (result);
2407 		}
2408 		if (c == '\n')
2409 			break;
2410 		*cp++ = c;
2411 	}
2412 	*cp = '\0';
2413 
2414 	if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local,
2415 	    user) == 3 && ntohs(hisport) == remote && ntohs(myport) == local) {
2416 		/* Strip trailing carriage return. */
2417 		if ((cp = strchr(user, '\r')) != NULL)
2418 			*cp = 0;
2419 		result = user;
2420 	}
2421 
2422 	alarm(0);
2423 	close(s);
2424 	return (result);
2425 }
2426 #endif
2427 
2428 /*
2429  * check if the address/port where send data to is one of the obvious ports
2430  * that are used for denial of service attacks like two echo ports
2431  * just echoing data between them
2432  */
2433 static int
2434 port_good_dg(struct sockaddr *sa)
2435 {
2436 	struct in_addr in;
2437 #ifdef INET6
2438 	struct in6_addr *in6;
2439 #endif
2440 	u_int16_t port;
2441 	int i, bad;
2442 	char hbuf[NI_MAXHOST];
2443 
2444 	bad = 0;
2445 
2446 	switch (sa->sa_family) {
2447 	case AF_INET:
2448 		in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
2449 		port = ntohs(((struct sockaddr_in *)sa)->sin_port);
2450 #ifdef INET6
2451 	v4chk:
2452 #endif
2453 		if (IN_MULTICAST(in.s_addr))
2454 			goto bad;
2455 		switch ((in.s_addr & 0xff000000) >> 24) {
2456 		case 0: case 127: case 255:
2457 			goto bad;
2458 		}
2459 		if (dg_broadcast(&in))
2460 			goto bad;
2461 		break;
2462 #ifdef INET6
2463 	case AF_INET6:
2464 		in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
2465 		port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
2466 		if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
2467 			goto bad;
2468 		if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
2469 			memcpy(&in, &in6->s6_addr[12], sizeof(in));
2470 			in.s_addr = ntohl(in.s_addr);
2471 			goto v4chk;
2472 		}
2473 		break;
2474 #endif
2475 	default:
2476 		/* XXX unsupported af, is it safe to assume it to be safe? */
2477 		return (1);
2478 	}
2479 
2480 	for (i = 0; bad_ports[i] != 0; i++) {
2481 		if (port == bad_ports[i])
2482 			goto bad;
2483 	}
2484 
2485 	return (1);
2486 
2487 bad:
2488 	if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0,
2489 	    niflags) != 0)
2490 		strlcpy(hbuf, "?", sizeof(hbuf));
2491 	syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d",
2492 		hbuf, port);
2493 	return (0);
2494 }
2495 
2496 /* XXX need optimization */
2497 static int
2498 dg_broadcast(struct in_addr *in)
2499 {
2500 	struct ifaddrs *ifa, *ifap;
2501 	struct sockaddr_in *sin;
2502 
2503 	if (getifaddrs(&ifap) < 0)
2504 		return (0);
2505 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
2506 		if (ifa->ifa_addr->sa_family != AF_INET ||
2507 		    (ifa->ifa_flags & IFF_BROADCAST) == 0)
2508 			continue;
2509 		sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
2510 		if (sin->sin_addr.s_addr == in->s_addr) {
2511 			freeifaddrs(ifap);
2512 			return (1);
2513 		}
2514 	}
2515 	freeifaddrs(ifap);
2516 	return (0);
2517 }
2518 
2519 static int
2520 my_kevent(const struct kevent *changelist, size_t nchanges,
2521     struct kevent *eventlist, size_t nevents)
2522 {
2523 	int	result;
2524 
2525 	while ((result = kevent(kq, changelist, nchanges, eventlist, nevents,
2526 	    NULL)) < 0)
2527 		if (errno != EINTR) {
2528 			syslog(LOG_ERR, "kevent: %m");
2529 			exit(EXIT_FAILURE);
2530 		}
2531 
2532 	return (result);
2533 }
2534 
2535 static struct kevent *
2536 allocchange(void)
2537 {
2538 	if (changes == A_CNT(changebuf)) {
2539 		(void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0);
2540 		changes = 0;
2541 	}
2542 
2543 	return (&changebuf[changes++]);
2544 }
2545