xref: /openbsd/usr.sbin/inetd/inetd.c (revision 097a140d)
1 /*	$OpenBSD: inetd.c,v 1.162 2020/12/30 18:41:06 benno Exp $	*/
2 
3 /*
4  * Copyright (c) 1983,1991 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Inetd - Internet super-server
34  *
35  * This program invokes all internet services as needed.
36  * connection-oriented services are invoked each time a
37  * connection is made, by creating a process.  This process
38  * is passed the connection as file descriptor 0 and is
39  * expected to do a getpeername to find out the source host
40  * and port.
41  *
42  * Datagram oriented services are invoked when a datagram
43  * arrives; a process is created and passed a pending message
44  * on file descriptor 0.  Datagram servers may either connect
45  * to their peer, freeing up the original socket for inetd
46  * to receive further messages on, or ``take over the socket'',
47  * processing all arriving datagrams and, eventually, timing
48  * out.	 The first type of server is said to be ``multi-threaded'';
49  * the second type of server ``single-threaded''.
50  *
51  * Inetd uses a configuration file which is read at startup
52  * and, possibly, at some later time in response to a hangup signal.
53  * The configuration file is ``free format'' with fields given in the
54  * order shown below.  Continuation lines for an entry must begin with
55  * a space or tab.  All fields must be present in each entry.
56  *
57  *	service name			must be in /etc/services
58  *	socket type			stream/dgram
59  *	protocol			must be in /etc/protocols
60  *	wait/nowait[.max]		single-threaded/multi-threaded, max #
61  *	user[.group] or user[:group]	user/group to run daemon as
62  *	server program			full path name
63  *	server program arguments	maximum of MAXARGS (20)
64  *
65  * For RPC services
66  *      service name/version            must be in /etc/rpc
67  *	socket type			stream/dgram
68  *	protocol			must be in /etc/protocols
69  *	wait/nowait[.max]		single-threaded/multi-threaded
70  *	user[.group] or user[:group]	user to run daemon as
71  *	server program			full path name
72  *	server program arguments	maximum of MAXARGS (20)
73  *
74  * For non-RPC services, the "service name" can be of the form
75  * hostaddress:servicename, in which case the hostaddress is used
76  * as the host portion of the address to listen on.  If hostaddress
77  * consists of a single `*' character, INADDR_ANY is used.
78  *
79  * A line can also consist of just
80  *      hostaddress:
81  * where hostaddress is as in the preceding paragraph.  Such a line must
82  * have no further fields; the specified hostaddress is remembered and
83  * used for all further lines that have no hostaddress specified,
84  * until the next such line (or EOF).  (This is why * is provided to
85  * allow explicit specification of INADDR_ANY.)  A line
86  *      *:
87  * is implicitly in effect at the beginning of the file.
88  *
89  * The hostaddress specifier may (and often will) contain dots;
90  * the service name must not.
91  *
92  * For RPC services, host-address specifiers are accepted and will
93  * work to some extent; however, because of limitations in the
94  * portmapper interface, it will not work to try to give more than
95  * one line for any given RPC service, even if the host-address
96  * specifiers are different.
97  *
98  * Comment lines are indicated by a `#' in column 1.
99  */
100 
101 /*
102  * Here's the scoop concerning the user[.:]group feature:
103  *
104  * 1) set-group-option off.
105  *
106  *	a) user = root:	NO setuid() or setgid() is done
107  *
108  *	b) other:	setgid(primary group as found in passwd)
109  *			initgroups(name, primary group)
110  *			setuid()
111  *
112  * 2) set-group-option on.
113  *
114  *	a) user = root:	setgid(specified group)
115  *			NO initgroups()
116  *			NO setuid()
117  *
118  *	b) other:	setgid(specified group)
119  *			initgroups(name, specified group)
120  *			setuid()
121  *
122  */
123 
124 #include <sys/stat.h>
125 #include <sys/socket.h>
126 #include <sys/un.h>
127 #include <sys/wait.h>
128 #include <sys/time.h>
129 #include <sys/resource.h>
130 
131 #include <net/if.h>
132 #include <netinet/in.h>
133 #include <arpa/inet.h>
134 
135 #include <err.h>
136 #include <errno.h>
137 #include <ctype.h>
138 #include <signal.h>
139 #include <netdb.h>
140 #include <syslog.h>
141 #include <pwd.h>
142 #include <grp.h>
143 #include <stdio.h>
144 #include <stdlib.h>
145 #include <unistd.h>
146 #include <limits.h>
147 #include <string.h>
148 #include <login_cap.h>
149 #include <ifaddrs.h>
150 #include <rpc/rpc.h>
151 #include <rpc/pmap_clnt.h>
152 #include <rpcsvc/nfs_prot.h>
153 #include <event.h>
154 #include "pathnames.h"
155 
156 #define MINIMUM(a, b)	(((a) < (b)) ? (a) : (b))
157 
158 #define	TOOMANY		256		/* don't start more than TOOMANY */
159 #define	CNT_INTVL	60		/* servers in CNT_INTVL sec. */
160 #define	RETRYTIME	(60*10)		/* retry after bind or server fail */
161 
162 int	 debug = 0;
163 int	 maxsock;
164 int	 toomany = TOOMANY;
165 int	 timingout;
166 struct	 servent *sp;
167 uid_t	 uid;
168 
169 #ifndef OPEN_MAX
170 #define OPEN_MAX	64
171 #endif
172 
173 /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
174 #define FD_MARGIN	(8)
175 rlim_t	rlim_nofile_cur = OPEN_MAX;
176 
177 struct rlimit	rlim_nofile;
178 
179 struct	servtab {
180 	char	*se_hostaddr;		/* host address to listen on */
181 	char	*se_service;		/* name of service */
182 	int	se_socktype;		/* type of socket to use */
183 	int	se_family;		/* address family */
184 	char	*se_proto;		/* protocol used */
185 	int	se_rpcprog;		/* rpc program number */
186 	int	se_rpcversl;		/* rpc program lowest version */
187 	int	se_rpcversh;		/* rpc program highest version */
188 #define isrpcservice(sep)	((sep)->se_rpcversl != 0)
189 	pid_t	se_wait;		/* single threaded server */
190 	short	se_checked;		/* looked at during merge */
191 	char	*se_user;		/* user name to run as */
192 	char	*se_group;		/* group name to run as */
193 	struct	biltin *se_bi;		/* if built-in, description */
194 	char	*se_server;		/* server program */
195 #define	MAXARGV 20
196 	char	*se_argv[MAXARGV+1];	/* program arguments */
197 	int	se_fd;			/* open descriptor */
198 	union {
199 		struct	sockaddr se_un_ctrladdr;
200 		struct	sockaddr_in se_un_ctrladdr_in;
201 		struct	sockaddr_in6 se_un_ctrladdr_in6;
202 		struct	sockaddr_un se_un_ctrladdr_un;
203 		struct	sockaddr_storage se_un_ctrladdr_storage;
204 	} se_un;			/* bound address */
205 #define se_ctrladdr	se_un.se_un_ctrladdr
206 #define se_ctrladdr_in	se_un.se_un_ctrladdr_in
207 #define se_ctrladdr_in6	se_un.se_un_ctrladdr_in6
208 #define se_ctrladdr_un	se_un.se_un_ctrladdr_un
209 #define se_ctrladdr_storage	se_un.se_un_ctrladdr_storage
210 	int	se_ctrladdr_size;
211 	int	se_max;			/* max # of instances of this service */
212 	int	se_count;		/* number started since se_time */
213 	struct	timeval se_time;	/* start of se_count */
214 	struct	servtab *se_next;
215 	struct	event se_event;
216 } *servtab;
217 
218 void echo_stream(int, struct servtab *);
219 void discard_stream(int, struct servtab *);
220 void machtime_stream(int, struct servtab *);
221 void daytime_stream(int, struct servtab *);
222 void chargen_stream(int, struct servtab *);
223 void echo_dg(int, struct servtab *);
224 void discard_dg(int, struct servtab *);
225 void machtime_dg(int, struct servtab *);
226 void daytime_dg(int, struct servtab *);
227 void chargen_dg(int, struct servtab *);
228 
229 struct biltin {
230 	char	*bi_service;		/* internally provided service name */
231 	int	bi_socktype;		/* type of socket supported */
232 	short	bi_fork;		/* 1 if should fork before call */
233 	short	bi_wait;		/* 1 if should wait for child */
234 	void	(*bi_fn)(int, struct servtab *);
235 } biltins[] = {
236 	/* Echo received data */
237 	{ "echo",	SOCK_STREAM,	1, 0,	echo_stream },
238 	{ "echo",	SOCK_DGRAM,	0, 0,	echo_dg },
239 
240 	/* Internet /dev/null */
241 	{ "discard",	SOCK_STREAM,	1, 0,	discard_stream },
242 	{ "discard",	SOCK_DGRAM,	0, 0,	discard_dg },
243 
244 	/* Return 32 bit time since 1900 */
245 	{ "time",	SOCK_STREAM,	0, 0,	machtime_stream },
246 	{ "time",	SOCK_DGRAM,	0, 0,	machtime_dg },
247 
248 	/* Return human-readable time */
249 	{ "daytime",	SOCK_STREAM,	0, 0,	daytime_stream },
250 	{ "daytime",	SOCK_DGRAM,	0, 0,	daytime_dg },
251 
252 	/* Familiar character generator */
253 	{ "chargen",	SOCK_STREAM,	1, 0,	chargen_stream },
254 	{ "chargen",	SOCK_DGRAM,	0, 0,	chargen_dg },
255 
256 	{ 0 }
257 };
258 
259 struct event evsig_alrm;
260 struct event evsig_hup;
261 struct event evsig_chld;
262 struct event evsig_term;
263 struct event evsig_int;
264 
265 void	config(int, short, void *);
266 void	reap(int, short, void *);
267 void	retry(int, short, void *);
268 void	die(int, short, void *);
269 
270 void	spawn(int, short, void *);
271 void	gettcp(int, short, void *);
272 int	setconfig(void);
273 void	endconfig(void);
274 void	register_rpc(struct servtab *);
275 void	unregister_rpc(struct servtab *);
276 void	freeconfig(struct servtab *);
277 void	print_service(char *, struct servtab *);
278 void	setup(struct servtab *);
279 struct servtab *getconfigent(void);
280 int	bump_nofile(void);
281 struct servtab *enter(struct servtab *);
282 int	matchconf(struct servtab *, struct servtab *);
283 int	dg_broadcast(struct in_addr *in);
284 
285 #define NUMINT	(sizeof(intab) / sizeof(struct inent))
286 char	*CONFIG = _PATH_INETDCONF;
287 
288 int		dg_badinput(struct sockaddr *sa);
289 void		inetd_setproctitle(char *a, int s);
290 void		initring(void);
291 u_int32_t	machtime(void);
292 
293 int
294 main(int argc, char *argv[])
295 {
296 	int ch;
297 
298 	while ((ch = getopt(argc, argv, "dR:")) != -1)
299 		switch (ch) {
300 		case 'd':
301 			debug = 1;
302 			break;
303 		case 'R': {	/* invocation rate */
304 			char *p;
305 			int val;
306 
307 			val = strtoul(optarg, &p, 0);
308 			if (val >= 1 && *p == '\0') {
309 				toomany = val;
310 				break;
311 			}
312 			syslog(LOG_ERR,
313 			    "-R %s: bad value for service invocation rate",
314 			    optarg);
315 			break;
316 		}
317 		case '?':
318 		default:
319 			fprintf(stderr,
320 			    "usage: inetd [-d] [-R rate] [configuration_file]\n");
321 			exit(1);
322 		}
323 	argc -= optind;
324 	argv += optind;
325 
326 	uid = getuid();
327 	if (uid != 0)
328 		CONFIG = NULL;
329 	if (argc > 0)
330 		CONFIG = argv[0];
331 	if (CONFIG == NULL) {
332 		fprintf(stderr, "inetd: non-root must specify a config file\n");
333 		exit(1);
334 	}
335 	if (argc > 1) {
336 		fprintf(stderr, "inetd: more than one argument specified\n");
337 		exit(1);
338 	}
339 
340 	umask(022);
341 	if (debug == 0) {
342 		daemon(0, 0);
343 		if (uid == 0)
344 			(void) setlogin("");
345 	}
346 
347 	if (pledge("stdio rpath cpath getpw dns inet unix proc exec id", NULL) == -1)
348 		err(1, "pledge");
349 
350 	if (uid == 0) {
351 		gid_t gid = getgid();
352 
353 		/* If run by hand, ensure groups vector gets trashed */
354 		setgroups(1, &gid);
355 	}
356 
357 	openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
358 
359 	if (getrlimit(RLIMIT_NOFILE, &rlim_nofile) == -1) {
360 		syslog(LOG_ERR, "getrlimit: %m");
361 	} else {
362 		rlim_nofile_cur = rlim_nofile.rlim_cur;
363 		if (rlim_nofile_cur == RLIM_INFINITY)	/* ! */
364 			rlim_nofile_cur = OPEN_MAX;
365 	}
366 
367 	event_init();
368 
369 	signal_set(&evsig_alrm, SIGALRM, retry, NULL);
370 	signal_add(&evsig_alrm, NULL);
371 
372 	config(0, 0, NULL);
373 
374 	signal_set(&evsig_hup, SIGHUP, config, NULL);
375 	signal_add(&evsig_hup, NULL);
376 	signal_set(&evsig_chld, SIGCHLD, reap, NULL);
377 	signal_add(&evsig_chld, NULL);
378 	signal_set(&evsig_term, SIGTERM, die, NULL);
379 	signal_add(&evsig_term, NULL);
380 	signal_set(&evsig_int, SIGINT, die, NULL);
381 	signal_add(&evsig_int, NULL);
382 
383 	signal(SIGPIPE, SIG_IGN);
384 
385 	event_dispatch();
386 
387 	return (0);
388 }
389 
390 void
391 gettcp(int fd, short events, void *xsep)
392 {
393 	struct servtab *sep = xsep;
394 	int ctrl;
395 
396 	if (debug)
397 		fprintf(stderr, "someone wants %s\n", sep->se_service);
398 
399 	ctrl = accept(sep->se_fd, NULL, NULL);
400 	if (debug)
401 		fprintf(stderr, "accept, ctrl %d\n", ctrl);
402 	if (ctrl == -1) {
403 		if (errno != EWOULDBLOCK && errno != EINTR &&
404 		    errno != ECONNABORTED)
405 			syslog(LOG_WARNING, "accept (for %s): %m",
406 			    sep->se_service);
407 		return;
408 	}
409 	if ((sep->se_family == AF_INET || sep->se_family == AF_INET6) &&
410 	    sep->se_socktype == SOCK_STREAM) {
411 		struct sockaddr_storage peer;
412 		socklen_t plen = sizeof(peer);
413 		char sbuf[NI_MAXSERV];
414 
415 		if (getpeername(ctrl, (struct sockaddr *)&peer, &plen) == -1) {
416 			syslog(LOG_WARNING, "could not getpeername");
417 			close(ctrl);
418 			return;
419 		}
420 		if (getnameinfo((struct sockaddr *)&peer, plen, NULL, 0,
421 		    sbuf, sizeof(sbuf), NI_NUMERICSERV) == 0 &&
422 		    strtonum(sbuf, 1, USHRT_MAX, NULL) == 20) {
423 			/*
424 			 * ignore things that look like ftp bounce
425 			 */
426 			close(ctrl);
427 			return;
428 		}
429 	}
430 
431 	spawn(ctrl, 0, sep);
432 }
433 
434 int
435 dg_badinput(struct sockaddr *sa)
436 {
437 	struct in_addr in;
438 	struct in6_addr *in6;
439 	u_int16_t port;
440 
441 	switch (sa->sa_family) {
442 	case AF_INET:
443 		in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
444 		port = ntohs(((struct sockaddr_in *)sa)->sin_port);
445 		if (IN_MULTICAST(in.s_addr))
446 			goto bad;
447 		switch ((in.s_addr & 0xff000000) >> 24) {
448 		case 0: case 127: case 255:
449 			goto bad;
450 		}
451 		if (dg_broadcast(&in))
452 			goto bad;
453 		break;
454 	case AF_INET6:
455 		in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
456 		port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
457 		if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
458 			goto bad;
459 		/*
460 		 * OpenBSD does not support IPv4-mapped and
461 		 * IPv4-compatible IPv6 addresses (RFC2553). We should
462 		 * drop the packet.
463 		 */
464 		if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6))
465 			goto bad;
466 		break;
467 	default:
468 		/* Unsupported AF */
469 		goto bad;
470 	}
471 
472 	if (port < IPPORT_RESERVED || port == NFS_PORT)
473 		goto bad;
474 
475 	return (0);
476 
477 bad:
478 	return (1);
479 }
480 
481 int
482 dg_broadcast(struct in_addr *in)
483 {
484 	struct ifaddrs *ifa, *ifap;
485 	struct sockaddr_in *sin;
486 
487 	if (getifaddrs(&ifap) == -1)
488 		return (0);
489 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
490 		if (ifa->ifa_addr == NULL ||
491 		    ifa->ifa_addr->sa_family != AF_INET ||
492 		    (ifa->ifa_flags & IFF_BROADCAST) == 0)
493 			continue;
494 		sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
495 		if (sin->sin_addr.s_addr == in->s_addr) {
496 			freeifaddrs(ifap);
497 			return (1);
498 		}
499 	}
500 	freeifaddrs(ifap);
501 	return (0);
502 }
503 
504 void
505 reap(int sig, short event, void *arg)
506 {
507 	struct servtab *sep;
508 	int status;
509 	pid_t pid;
510 
511 	if (debug)
512 		fprintf(stderr, "reaping asked for\n");
513 
514 	for (;;) {
515 		if ((pid = wait3(&status, WNOHANG, NULL)) <= 0) {
516 			if (pid == -1 && errno == EINTR)
517 				continue;
518 			break;
519 		}
520 		if (debug)
521 			fprintf(stderr, "%ld reaped, status %x\n",
522 			    (long)pid, status);
523 		for (sep = servtab; sep; sep = sep->se_next)
524 			if (sep->se_wait == pid) {
525 				if (WIFEXITED(status) && WEXITSTATUS(status))
526 					syslog(LOG_WARNING,
527 					    "%s: exit status %d",
528 					    sep->se_server, WEXITSTATUS(status));
529 				else if (WIFSIGNALED(status))
530 					syslog(LOG_WARNING,
531 					    "%s: exit signal %d",
532 					    sep->se_server, WTERMSIG(status));
533 				sep->se_wait = 1;
534 				event_add(&sep->se_event, NULL);
535 				if (debug)
536 					fprintf(stderr, "restored %s, fd %d\n",
537 					    sep->se_service, sep->se_fd);
538 			}
539 	}
540 }
541 
542 void
543 config(int sig, short event, void *arg)
544 {
545 	struct servtab *sep, *cp, **sepp;
546 	int add;
547 	char protoname[11];
548 
549 	if (!setconfig()) {
550 		syslog(LOG_ERR, "%s: %m", CONFIG);
551 		exit(1);
552 	}
553 	for (sep = servtab; sep; sep = sep->se_next)
554 		sep->se_checked = 0;
555 	cp = getconfigent();
556 	while (cp != NULL) {
557 		for (sep = servtab; sep; sep = sep->se_next)
558 			if (matchconf(sep, cp))
559 				break;
560 		add = 0;
561 		if (sep != NULL) {
562 			int i;
563 
564 #define SWAP(type, a, b) {type c=(type)a; a=(type)b; b=(type)c;}
565 
566 			/*
567 			 * sep->se_wait may be holding the pid of a daemon
568 			 * that we're waiting for.  If so, don't overwrite
569 			 * it unless the config file explicitly says don't
570 			 * wait.
571 			 */
572 			if (cp->se_bi == 0 &&
573 			    (sep->se_wait == 1 || cp->se_wait == 0))
574 				sep->se_wait = cp->se_wait;
575 			SWAP(int, cp->se_max, sep->se_max);
576 			SWAP(char *, sep->se_user, cp->se_user);
577 			SWAP(char *, sep->se_group, cp->se_group);
578 			SWAP(char *, sep->se_server, cp->se_server);
579 			for (i = 0; i < MAXARGV; i++)
580 				SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
581 #undef SWAP
582 			if (isrpcservice(sep))
583 				unregister_rpc(sep);
584 			sep->se_rpcversl = cp->se_rpcversl;
585 			sep->se_rpcversh = cp->se_rpcversh;
586 			freeconfig(cp);
587 			add = 1;
588 		} else {
589 			sep = enter(cp);
590 		}
591 		sep->se_checked = 1;
592 
593 		switch (sep->se_family) {
594 		case AF_UNIX:
595 			if (sep->se_fd != -1)
596 				break;
597 			sep->se_ctrladdr_size =
598 			    strlcpy(sep->se_ctrladdr_un.sun_path,
599 			    sep->se_service,
600 			    sizeof sep->se_ctrladdr_un.sun_path);
601 			if (sep->se_ctrladdr_size >=
602 			    sizeof sep->se_ctrladdr_un.sun_path) {
603 				syslog(LOG_WARNING, "%s/%s: UNIX domain socket "
604 				    "path too long", sep->se_service,
605 				    sep->se_proto);
606 				goto serv_unknown;
607 			}
608 			sep->se_ctrladdr_un.sun_family = AF_UNIX;
609 			sep->se_ctrladdr_size +=
610 			    1 + sizeof sep->se_ctrladdr_un.sun_family;
611 			(void)unlink(sep->se_service);
612 			setup(sep);
613 			break;
614 		case AF_INET:
615 			sep->se_ctrladdr_in.sin_family = AF_INET;
616 			/* se_ctrladdr_in was set in getconfigent */
617 			sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in;
618 
619 			if (isrpcservice(sep)) {
620 				struct rpcent *rp;
621 
622 				sep->se_rpcprog = strtonum(sep->se_service,
623 				    1, USHRT_MAX, NULL);
624 				if (sep->se_rpcprog == 0) {
625 					rp = getrpcbyname(sep->se_service);
626 					if (rp == 0) {
627 						syslog(LOG_ERR,
628 						    "%s: unknown rpc service",
629 						    sep->se_service);
630 						goto serv_unknown;
631 					}
632 					sep->se_rpcprog = rp->r_number;
633 				}
634 				if (sep->se_fd == -1)
635 					setup(sep);
636 				if (sep->se_fd != -1)
637 					register_rpc(sep);
638 			} else {
639 				u_short port = htons(strtonum(sep->se_service,
640 				    1, USHRT_MAX, NULL));
641 
642 				if (!port) {
643 					(void)strlcpy(protoname, sep->se_proto,
644 					    sizeof(protoname));
645 					if (isdigit((unsigned char)
646 					    protoname[strlen(protoname) - 1]))
647 						protoname[strlen(protoname) - 1] = '\0';
648 					sp = getservbyname(sep->se_service,
649 					    protoname);
650 					if (sp == 0) {
651 						syslog(LOG_ERR,
652 						    "%s/%s: unknown service",
653 						    sep->se_service, sep->se_proto);
654 						goto serv_unknown;
655 					}
656 					port = sp->s_port;
657 				}
658 				if (port != sep->se_ctrladdr_in.sin_port) {
659 					sep->se_ctrladdr_in.sin_port = port;
660 					if (sep->se_fd != -1) {
661 						event_del(&sep->se_event);
662 						(void) close(sep->se_fd);
663 					}
664 					sep->se_fd = -1;
665 				}
666 				if (sep->se_fd == -1)
667 					setup(sep);
668 			}
669 			break;
670 		case AF_INET6:
671 			sep->se_ctrladdr_in6.sin6_family = AF_INET6;
672 			/* se_ctrladdr_in was set in getconfigent */
673 			sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in6;
674 
675 			if (isrpcservice(sep)) {
676 				struct rpcent *rp;
677 
678 				sep->se_rpcprog = strtonum(sep->se_service,
679 				    1, USHRT_MAX, NULL);
680 				if (sep->se_rpcprog == 0) {
681 					rp = getrpcbyname(sep->se_service);
682 					if (rp == 0) {
683 						syslog(LOG_ERR,
684 						    "%s: unknown rpc service",
685 						    sep->se_service);
686 						goto serv_unknown;
687 					}
688 					sep->se_rpcprog = rp->r_number;
689 				}
690 				if (sep->se_fd == -1)
691 					setup(sep);
692 				if (sep->se_fd != -1)
693 					register_rpc(sep);
694 			} else {
695 				u_short port = htons(strtonum(sep->se_service,
696 				    1, USHRT_MAX, NULL));
697 
698 				if (!port) {
699 					(void)strlcpy(protoname, sep->se_proto,
700 					    sizeof(protoname));
701 					if (isdigit((unsigned char)
702 					    protoname[strlen(protoname) - 1]))
703 						protoname[strlen(protoname) - 1] = '\0';
704 					sp = getservbyname(sep->se_service,
705 					    protoname);
706 					if (sp == 0) {
707 						syslog(LOG_ERR,
708 						    "%s/%s: unknown service",
709 						    sep->se_service, sep->se_proto);
710 						goto serv_unknown;
711 					}
712 					port = sp->s_port;
713 				}
714 				if (port != sep->se_ctrladdr_in6.sin6_port) {
715 					sep->se_ctrladdr_in6.sin6_port = port;
716 					if (sep->se_fd != -1) {
717 						event_del(&sep->se_event);
718 						(void) close(sep->se_fd);
719 					}
720 					sep->se_fd = -1;
721 				}
722 				if (sep->se_fd == -1)
723 					setup(sep);
724 			}
725 			break;
726 		}
727 	serv_unknown:
728 		if (cp->se_next != NULL) {
729 			struct servtab *tmp = cp;
730 
731 			cp = cp->se_next;
732 			free(tmp);
733 		} else {
734 			free(cp);
735 			cp = getconfigent();
736 		}
737 		if (debug)
738 			print_service(add ? "REDO" : "ADD", sep);
739 	}
740 	endconfig();
741 	/*
742 	 * Purge anything not looked at above.
743 	 */
744 	sepp = &servtab;
745 	while ((sep = *sepp)) {
746 		if (sep->se_checked) {
747 			sepp = &sep->se_next;
748 			continue;
749 		}
750 		*sepp = sep->se_next;
751 		if (sep->se_fd != -1) {
752 			event_del(&sep->se_event);
753 			(void) close(sep->se_fd);
754 		}
755 		if (isrpcservice(sep))
756 			unregister_rpc(sep);
757 		if (sep->se_family == AF_UNIX)
758 			(void)unlink(sep->se_service);
759 		if (debug)
760 			print_service("FREE", sep);
761 		freeconfig(sep);
762 		free(sep);
763 	}
764 }
765 
766 void
767 retry(int sig, short events, void *arg)
768 {
769 	struct servtab *sep;
770 
771 	timingout = 0;
772 	for (sep = servtab; sep; sep = sep->se_next) {
773 		if (sep->se_fd == -1) {
774 			switch (sep->se_family) {
775 			case AF_UNIX:
776 			case AF_INET:
777 			case AF_INET6:
778 				setup(sep);
779 				if (sep->se_fd != -1 && isrpcservice(sep))
780 					register_rpc(sep);
781 				break;
782 			}
783 		}
784 	}
785 }
786 
787 void
788 die(int sig, short events, void *arg)
789 {
790 	struct servtab *sep;
791 
792 	for (sep = servtab; sep; sep = sep->se_next) {
793 		if (sep->se_fd == -1)
794 			continue;
795 
796 		switch (sep->se_family) {
797 		case AF_UNIX:
798 			(void)unlink(sep->se_service);
799 			break;
800 		case AF_INET:
801 		case AF_INET6:
802 			if (sep->se_wait == 1 && isrpcservice(sep))
803 				unregister_rpc(sep);
804 			break;
805 		}
806 		(void)close(sep->se_fd);
807 	}
808 	exit(0);
809 }
810 
811 void
812 setup(struct servtab *sep)
813 {
814 	int on = 1;
815 	int r;
816 	mode_t mask = 0;
817 
818 	if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) == -1) {
819 		syslog(LOG_ERR, "%s/%s: socket: %m",
820 		    sep->se_service, sep->se_proto);
821 		return;
822 	}
823 #define	turnon(fd, opt) \
824 setsockopt(fd, SOL_SOCKET, opt, &on, sizeof (on))
825 	if (strncmp(sep->se_proto, "tcp", 3) == 0 && debug &&
826 	    turnon(sep->se_fd, SO_DEBUG) < 0)
827 		syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
828 	if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
829 		syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
830 #undef turnon
831 	if (isrpcservice(sep)) {
832 		struct passwd *pwd;
833 
834 		/*
835 		 * for RPC services, attempt to use a reserved port
836 		 * if they are going to be running as root.
837 		 *
838 		 * Also, zero out the port for all RPC services; let bind()
839 		 * find one.
840 		 */
841 		sep->se_ctrladdr_in.sin_port = 0;
842 		if (sep->se_user && (pwd = getpwnam(sep->se_user)) &&
843 		    pwd->pw_uid == 0 && uid == 0)
844 			r = bindresvport(sep->se_fd, &sep->se_ctrladdr_in);
845 		else {
846 			r = bind(sep->se_fd, &sep->se_ctrladdr,
847 			    sep->se_ctrladdr_size);
848 			if (r == 0) {
849 				socklen_t len = sep->se_ctrladdr_size;
850 				int saveerrno = errno;
851 
852 				/* update se_ctrladdr_in.sin_port */
853 				r = getsockname(sep->se_fd, &sep->se_ctrladdr,
854 				    &len);
855 				if (r <= 0)
856 					errno = saveerrno;
857 			}
858 		}
859 	} else {
860 		if (sep->se_family == AF_UNIX)
861 			mask = umask(0111);
862 		r = bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size);
863 		if (sep->se_family == AF_UNIX)
864 			umask(mask);
865 	}
866 	if (r == -1) {
867 		syslog(LOG_ERR, "%s/%s: bind: %m",
868 		    sep->se_service, sep->se_proto);
869 		(void) close(sep->se_fd);
870 		sep->se_fd = -1;
871 		if (!timingout) {
872 			timingout = 1;
873 			alarm(RETRYTIME);
874 		}
875 		return;
876 	}
877 	if (sep->se_socktype == SOCK_STREAM)
878 		listen(sep->se_fd, 10);
879 
880 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
881 		event_set(&sep->se_event, sep->se_fd, EV_READ|EV_PERSIST,
882 		    gettcp, sep);
883 	} else {
884 		event_set(&sep->se_event, sep->se_fd, EV_READ|EV_PERSIST,
885 		    spawn, sep);
886 	}
887 
888 	event_add(&sep->se_event, NULL);
889 
890 	if (sep->se_fd > maxsock) {
891 		maxsock = sep->se_fd;
892 		if (maxsock > rlim_nofile_cur - FD_MARGIN)
893 			bump_nofile();
894 	}
895 }
896 
897 void
898 register_rpc(struct servtab *sep)
899 {
900 	socklen_t n;
901 	struct sockaddr_in sin;
902 	struct protoent *pp;
903 
904 	if ((pp = getprotobyname(sep->se_proto+4)) == NULL) {
905 		syslog(LOG_ERR, "%s: getproto: %m",
906 		    sep->se_proto);
907 		return;
908 	}
909 	n = sizeof sin;
910 	if (getsockname(sep->se_fd, (struct sockaddr *)&sin, &n) == -1) {
911 		syslog(LOG_ERR, "%s/%s: getsockname: %m",
912 		    sep->se_service, sep->se_proto);
913 		return;
914 	}
915 
916 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
917 		if (debug)
918 			fprintf(stderr, "pmap_set: %u %u %u %u\n",
919 			    sep->se_rpcprog, n, pp->p_proto,
920 			    ntohs(sin.sin_port));
921 		(void)pmap_unset(sep->se_rpcprog, n);
922 		if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(sin.sin_port)))
923 			syslog(LOG_ERR, "%s %s: pmap_set: %u %u %u %u: %m",
924 			    sep->se_service, sep->se_proto,
925 			    sep->se_rpcprog, n, pp->p_proto,
926 			    ntohs(sin.sin_port));
927 	}
928 }
929 
930 void
931 unregister_rpc(struct servtab *sep)
932 {
933 	int n;
934 
935 	for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
936 		if (debug)
937 			fprintf(stderr, "pmap_unset(%u, %u)\n",
938 			    sep->se_rpcprog, n);
939 		if (!pmap_unset(sep->se_rpcprog, n))
940 			syslog(LOG_ERR, "pmap_unset(%u, %u)",
941 			    sep->se_rpcprog, n);
942 	}
943 }
944 
945 
946 struct servtab *
947 enter(struct servtab *cp)
948 {
949 	struct servtab *sep;
950 
951 	sep = malloc(sizeof (*sep));
952 	if (sep == NULL) {
953 		syslog(LOG_ERR, "Out of memory.");
954 		exit(1);
955 	}
956 	*sep = *cp;
957 	sep->se_fd = -1;
958 	sep->se_rpcprog = -1;
959 	sep->se_next = servtab;
960 	servtab = sep;
961 	return (sep);
962 }
963 
964 int
965 matchconf(struct servtab *old, struct servtab *new)
966 {
967 	if (strcmp(old->se_service, new->se_service) != 0)
968 		return (0);
969 
970 	if (strcmp(old->se_hostaddr, new->se_hostaddr) != 0)
971 		return (0);
972 
973 	if (strcmp(old->se_proto, new->se_proto) != 0)
974 		return (0);
975 
976 	/*
977 	 * If the new servtab is bound to a specific address, check that the
978 	 * old servtab is bound to the same entry. If the new service is not
979 	 * bound to a specific address then the check of se_hostaddr above
980 	 * is sufficient.
981 	 */
982 
983 	if (old->se_family == AF_INET && new->se_family == AF_INET &&
984 	    bcmp(&old->se_ctrladdr_in.sin_addr,
985 	    &new->se_ctrladdr_in.sin_addr,
986 	    sizeof(new->se_ctrladdr_in.sin_addr)) != 0)
987 		return (0);
988 
989 	if (old->se_family == AF_INET6 && new->se_family == AF_INET6 &&
990 	    bcmp(&old->se_ctrladdr_in6.sin6_addr,
991 	    &new->se_ctrladdr_in6.sin6_addr,
992 	    sizeof(new->se_ctrladdr_in6.sin6_addr)) != 0)
993 		return (0);
994 	if (old->se_family == AF_INET6 && new->se_family == AF_INET6 &&
995 	    old->se_ctrladdr_in6.sin6_scope_id !=
996 	    new->se_ctrladdr_in6.sin6_scope_id)
997 		return (0);
998 
999 	return (1);
1000 }
1001 
1002 FILE		*fconfig = NULL;
1003 char		line[1024];
1004 char		*defhost;
1005 char		*skip(char **, int);
1006 char		*nextline(FILE *);
1007 char		*newstr(char *);
1008 struct servtab	*dupconfig(struct servtab *);
1009 
1010 int
1011 setconfig(void)
1012 {
1013 	free(defhost);
1014 	defhost = newstr("*");
1015 	if (fconfig != NULL) {
1016 		fseek(fconfig, 0L, SEEK_SET);
1017 		return (1);
1018 	}
1019 	fconfig = fopen(CONFIG, "r");
1020 	return (fconfig != NULL);
1021 }
1022 
1023 void
1024 endconfig(void)
1025 {
1026 	if (fconfig) {
1027 		(void) fclose(fconfig);
1028 		fconfig = NULL;
1029 	}
1030 	if (defhost) {
1031 		free(defhost);
1032 		defhost = 0;
1033 	}
1034 }
1035 
1036 struct servtab *
1037 getconfigent(void)
1038 {
1039 	struct servtab *sep, *tsep;
1040 	char *arg, *cp, *hostdelim, *s;
1041 	int argc;
1042 
1043 	sep = calloc(1, sizeof(struct servtab));
1044 	if (sep == NULL) {
1045 		syslog(LOG_ERR, "calloc: %m");
1046 		exit(1);
1047 	}
1048 more:
1049 	freeconfig(sep);
1050 
1051 	while ((cp = nextline(fconfig)) && *cp == '#')
1052 		;
1053 	if (cp == NULL) {
1054 		free(sep);
1055 		return (NULL);
1056 	}
1057 
1058 	memset(sep, 0, sizeof *sep);
1059 	arg = skip(&cp, 0);
1060 	if (arg == NULL) {
1061 		/* A blank line. */
1062 		goto more;
1063 	}
1064 
1065 	/* Check for a host name. */
1066 	hostdelim = strrchr(arg, ':');
1067 	if (hostdelim) {
1068 		*hostdelim = '\0';
1069 		if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
1070 			hostdelim[-1] = '\0';
1071 			sep->se_hostaddr = newstr(arg + 1);
1072 		} else if (hostdelim == arg)
1073 			sep->se_hostaddr = newstr("*");
1074 		else
1075 			sep->se_hostaddr = newstr(arg);
1076 		arg = hostdelim + 1;
1077 		/*
1078 		 * If the line is of the form `host:', then just change the
1079 		 * default host for the following lines.
1080 		 */
1081 		if (*arg == '\0') {
1082 			arg = skip(&cp, 0);
1083 			if (cp == NULL) {
1084 				free(defhost);
1085 				defhost = newstr(sep->se_hostaddr);
1086 				goto more;
1087 			}
1088 		}
1089 	} else
1090 		sep->se_hostaddr = newstr(defhost);
1091 
1092 	sep->se_service = newstr(arg);
1093 	if ((arg = skip(&cp, 1)) == NULL)
1094 		goto more;
1095 
1096 	if (strcmp(arg, "stream") == 0)
1097 		sep->se_socktype = SOCK_STREAM;
1098 	else if (strcmp(arg, "dgram") == 0)
1099 		sep->se_socktype = SOCK_DGRAM;
1100 	else
1101 		sep->se_socktype = -1;
1102 
1103 	if ((arg = skip(&cp, 1)) == NULL)
1104 		goto more;
1105 
1106 	sep->se_proto = newstr(arg);
1107 
1108 	if (strcmp(sep->se_proto, "unix") == 0) {
1109 		sep->se_family = AF_UNIX;
1110 	} else {
1111 		int s;
1112 
1113 		sep->se_family = AF_INET;
1114 		if (sep->se_proto[strlen(sep->se_proto) - 1] == '6')
1115 			sep->se_family = AF_INET6;
1116 
1117 		/* check if the family is supported */
1118 		s = socket(sep->se_family, SOCK_DGRAM, 0);
1119 		if (s == -1) {
1120 			syslog(LOG_WARNING, "%s/%s: %s: the address family is "
1121 			    "not supported by the kernel", sep->se_service,
1122 			    sep->se_proto, sep->se_hostaddr);
1123 			goto more;
1124 		}
1125 		close(s);
1126 
1127 		if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
1128 			char *cp, *ccp;
1129 			long l;
1130 
1131 			cp = strchr(sep->se_service, '/');
1132 			if (cp == 0) {
1133 				syslog(LOG_ERR, "%s: no rpc version",
1134 				    sep->se_service);
1135 				goto more;
1136 			}
1137 			*cp++ = '\0';
1138 			l = strtol(cp, &ccp, 0);
1139 			if (ccp == cp || l < 0 || l > INT_MAX) {
1140 		badafterall:
1141 				syslog(LOG_ERR, "%s/%s: bad rpc version",
1142 				    sep->se_service, cp);
1143 				goto more;
1144 			}
1145 			sep->se_rpcversl = sep->se_rpcversh = l;
1146 			if (*ccp == '-') {
1147 				cp = ccp + 1;
1148 				l = strtol(cp, &ccp, 0);
1149 				if (ccp == cp || l < 0 || l > INT_MAX ||
1150 				    l < sep->se_rpcversl || *ccp)
1151 					goto badafterall;
1152 				sep->se_rpcversh = l;
1153 			} else if (*ccp != '\0')
1154 				goto badafterall;
1155 		}
1156 	}
1157 	arg = skip(&cp, 1);
1158 	if (arg == NULL)
1159 		goto more;
1160 
1161 	s = strchr(arg, '.');
1162 	if (s) {
1163 		char *p;
1164 
1165 		*s++ = '\0';
1166 		sep->se_max = strtoul(s, &p, 0);
1167 		if (sep->se_max < 1 || *p) {
1168 			syslog(LOG_ERR,
1169 			    "%s: illegal max field \"%s\", setting to %d",
1170 			    sep->se_service, s, toomany);
1171 			sep->se_max = toomany;
1172 		}
1173 	} else
1174 		sep->se_max = toomany;
1175 
1176 	sep->se_wait = strcmp(arg, "wait") == 0;
1177 	if ((arg = skip(&cp, 1)) == NULL)
1178 		goto more;
1179 	sep->se_user = newstr(arg);
1180 	arg = strchr(sep->se_user, '.');
1181 	if (arg == NULL)
1182 		arg = strchr(sep->se_user, ':');
1183 	if (arg) {
1184 		*arg++ = '\0';
1185 		sep->se_group = newstr(arg);
1186 	}
1187 	if ((arg = skip(&cp, 1)) == NULL)
1188 		goto more;
1189 
1190 	sep->se_server = newstr(arg);
1191 	if (strcmp(sep->se_server, "internal") == 0) {
1192 		struct biltin *bi;
1193 
1194 		for (bi = biltins; bi->bi_service; bi++)
1195 			if (bi->bi_socktype == sep->se_socktype &&
1196 			    strcmp(bi->bi_service, sep->se_service) == 0)
1197 				break;
1198 		if (bi->bi_service == 0) {
1199 			syslog(LOG_ERR, "internal service %s unknown",
1200 			    sep->se_service);
1201 			goto more;
1202 		}
1203 		sep->se_bi = bi;
1204 		sep->se_wait = bi->bi_wait;
1205 	} else
1206 		sep->se_bi = NULL;
1207 	argc = 0;
1208 	for (arg = skip(&cp, 0); cp; arg = skip(&cp, 0)) {
1209 		if (argc < MAXARGV)
1210 			sep->se_argv[argc++] = newstr(arg);
1211 	}
1212 	if (argc == 0 && sep->se_bi == NULL) {
1213 		if ((arg = strrchr(sep->se_server, '/')) != NULL)
1214 			arg++;
1215 		else
1216 			arg = sep->se_server;
1217 		sep->se_argv[argc++] = newstr(arg);
1218 	}
1219 	while (argc <= MAXARGV)
1220 		sep->se_argv[argc++] = NULL;
1221 
1222 	/*
1223 	 * Resolve each hostname in the se_hostaddr list (if any)
1224 	 * and create a new entry for each resolved address.
1225 	 */
1226 	if (sep->se_hostaddr != NULL && strcmp(sep->se_proto, "unix") != 0) {
1227 		struct addrinfo hints, *res0, *res;
1228 		char *host, *hostlist0, *hostlist, *port;
1229 		int error;
1230 
1231 		hostlist = hostlist0 = sep->se_hostaddr;
1232 		sep->se_hostaddr = NULL;
1233 		sep->se_checked = -1;
1234 		while ((host = strsep(&hostlist, ",")) != NULL) {
1235 			if (*host == '\0')
1236 				continue;
1237 
1238 			memset(&hints, 0, sizeof(hints));
1239 			hints.ai_family = sep->se_family;
1240 			hints.ai_socktype = sep->se_socktype;
1241 			hints.ai_flags = AI_PASSIVE;
1242 			port = "0";
1243 			error = getaddrinfo(strcmp(host, "*") ? host : NULL,
1244 			    port, &hints, &res0);
1245 			if (error) {
1246 				syslog(LOG_ERR, "%s/%s: %s: %s",
1247 				    sep->se_service, sep->se_proto,
1248 				    host, gai_strerror(error));
1249 				continue;
1250 			}
1251 			for (res = res0; res; res = res->ai_next) {
1252 				/*
1253 				 * If sep is unused, store host in there.
1254 				 * Otherwise, dup a new entry and prepend it.
1255 				 */
1256 				if (sep->se_checked == -1) {
1257 					sep->se_checked = 0;
1258 				} else {
1259 					tsep = dupconfig(sep);
1260 					tsep->se_next = sep;
1261 					sep = tsep;
1262 				}
1263 				sep->se_hostaddr = newstr(host);
1264 				memcpy(&sep->se_ctrladdr_storage,
1265 				    res->ai_addr, res->ai_addrlen);
1266 				sep->se_ctrladdr_size = res->ai_addrlen;
1267 			}
1268 			freeaddrinfo(res0);
1269 		}
1270 		free(hostlist0);
1271 		if (sep->se_checked == -1)
1272 			goto more;	/* no resolvable names/addresses */
1273 	}
1274 
1275 	return (sep);
1276 }
1277 
1278 void
1279 freeconfig(struct servtab *cp)
1280 {
1281 	int i;
1282 
1283 	free(cp->se_hostaddr);
1284 	cp->se_hostaddr = NULL;
1285 	free(cp->se_service);
1286 	cp->se_service = NULL;
1287 	free(cp->se_proto);
1288 	cp->se_proto = NULL;
1289 	free(cp->se_user);
1290 	cp->se_user = NULL;
1291 	free(cp->se_group);
1292 	cp->se_group = NULL;
1293 	free(cp->se_server);
1294 	cp->se_server = NULL;
1295 	for (i = 0; i < MAXARGV; i++) {
1296 		free(cp->se_argv[i]);
1297 		cp->se_argv[i] = NULL;
1298 	}
1299 }
1300 
1301 char *
1302 skip(char **cpp, int report)
1303 {
1304 	char *cp = *cpp;
1305 	char *start;
1306 
1307 erp:
1308 	if (*cpp == NULL) {
1309 		if (report)
1310 			syslog(LOG_ERR, "syntax error in inetd config file");
1311 		return (NULL);
1312 	}
1313 
1314 again:
1315 	while (*cp == ' ' || *cp == '\t')
1316 		cp++;
1317 	if (*cp == '\0') {
1318 		int c;
1319 
1320 		c = getc(fconfig);
1321 		(void) ungetc(c, fconfig);
1322 		if (c == ' ' || c == '\t')
1323 			if ((cp = nextline(fconfig)))
1324 				goto again;
1325 		*cpp = NULL;
1326 		goto erp;
1327 	}
1328 	start = cp;
1329 	while (*cp && *cp != ' ' && *cp != '\t')
1330 		cp++;
1331 	if (*cp != '\0')
1332 		*cp++ = '\0';
1333 	if ((*cpp = cp) == NULL)
1334 		goto erp;
1335 
1336 	return (start);
1337 }
1338 
1339 char *
1340 nextline(FILE *fd)
1341 {
1342 	if (fgets(line, sizeof (line), fd) == NULL)
1343 		return (NULL);
1344 	line[strcspn(line, "\n")] = '\0';
1345 	return (line);
1346 }
1347 
1348 char *
1349 newstr(char *cp)
1350 {
1351 	if ((cp = strdup(cp ? cp : "")))
1352 		return(cp);
1353 	syslog(LOG_ERR, "strdup: %m");
1354 	exit(1);
1355 }
1356 
1357 struct servtab *
1358 dupconfig(struct servtab *sep)
1359 {
1360 	struct servtab *newtab;
1361 	int argc;
1362 
1363 	newtab = calloc(1, sizeof(struct servtab));
1364 
1365 	if (newtab == NULL) {
1366 		syslog(LOG_ERR, "calloc: %m");
1367 		exit(1);
1368 	}
1369 
1370 	newtab->se_service = sep->se_service ? newstr(sep->se_service) : NULL;
1371 	newtab->se_socktype = sep->se_socktype;
1372 	newtab->se_family = sep->se_family;
1373 	newtab->se_proto = sep->se_proto ? newstr(sep->se_proto) : NULL;
1374 	newtab->se_rpcprog = sep->se_rpcprog;
1375 	newtab->se_rpcversl = sep->se_rpcversl;
1376 	newtab->se_rpcversh = sep->se_rpcversh;
1377 	newtab->se_wait = sep->se_wait;
1378 	newtab->se_user = sep->se_user ? newstr(sep->se_user) : NULL;
1379 	newtab->se_group = sep->se_group ? newstr(sep->se_group) : NULL;
1380 	newtab->se_bi = sep->se_bi;
1381 	newtab->se_server = sep->se_server ? newstr(sep->se_server) : 0;
1382 
1383 	for (argc = 0; argc <= MAXARGV; argc++)
1384 		newtab->se_argv[argc] = sep->se_argv[argc] ?
1385 		    newstr(sep->se_argv[argc]) : NULL;
1386 	newtab->se_max = sep->se_max;
1387 
1388 	return (newtab);
1389 }
1390 
1391 void
1392 inetd_setproctitle(char *a, int s)
1393 {
1394 	socklen_t size;
1395 	struct sockaddr_storage ss;
1396 	char hbuf[NI_MAXHOST];
1397 
1398 	size = sizeof(ss);
1399 	if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) {
1400 		if (getnameinfo((struct sockaddr *)&ss, size, hbuf,
1401 		    sizeof(hbuf), NULL, 0, NI_NUMERICHOST) == 0)
1402 			setproctitle("-%s [%s]", a, hbuf);
1403 		else
1404 			setproctitle("-%s [?]", a);
1405 	} else
1406 		setproctitle("-%s", a);
1407 }
1408 
1409 int
1410 bump_nofile(void)
1411 {
1412 #define FD_CHUNK	32
1413 
1414 	struct rlimit rl;
1415 
1416 	if (getrlimit(RLIMIT_NOFILE, &rl) == -1) {
1417 		syslog(LOG_ERR, "getrlimit: %m");
1418 		return -1;
1419 	}
1420 	rl.rlim_cur = MINIMUM(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
1421 	rl.rlim_cur = MINIMUM(FD_SETSIZE, rl.rlim_cur + FD_CHUNK);
1422 	if (rl.rlim_cur <= rlim_nofile_cur) {
1423 		syslog(LOG_ERR,
1424 		    "bump_nofile: cannot extend file limit, max = %d",
1425 		    (int)rl.rlim_cur);
1426 		return -1;
1427 	}
1428 
1429 	if (setrlimit(RLIMIT_NOFILE, &rl) == -1) {
1430 		syslog(LOG_ERR, "setrlimit: %m");
1431 		return -1;
1432 	}
1433 
1434 	rlim_nofile_cur = rl.rlim_cur;
1435 	return 0;
1436 }
1437 
1438 /*
1439  * Internet services provided internally by inetd:
1440  */
1441 #define	BUFSIZE	4096
1442 
1443 void
1444 echo_stream(int s, struct servtab *sep)
1445 {
1446 	char buffer[BUFSIZE];
1447 	int i;
1448 
1449 	inetd_setproctitle(sep->se_service, s);
1450 	while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
1451 	    write(s, buffer, i) > 0)
1452 		;
1453 	exit(0);
1454 }
1455 
1456 void
1457 echo_dg(int s, struct servtab *sep)
1458 {
1459 	char buffer[BUFSIZE];
1460 	int i;
1461 	socklen_t size;
1462 	struct sockaddr_storage ss;
1463 
1464 	size = sizeof(ss);
1465 	if ((i = recvfrom(s, buffer, sizeof(buffer), 0,
1466 	    (struct sockaddr *)&ss, &size)) == -1)
1467 		return;
1468 	if (dg_badinput((struct sockaddr *)&ss))
1469 		return;
1470 	(void) sendto(s, buffer, i, 0, (struct sockaddr *)&ss, size);
1471 }
1472 
1473 void
1474 discard_stream(int s, struct servtab *sep)
1475 {
1476 	char buffer[BUFSIZE];
1477 
1478 	inetd_setproctitle(sep->se_service, s);
1479 	while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
1480 	    errno == EINTR)
1481 		;
1482 	exit(0);
1483 }
1484 
1485 void
1486 discard_dg(int s, struct servtab *sep)
1487 {
1488 	char buffer[BUFSIZE];
1489 
1490 	(void) read(s, buffer, sizeof(buffer));
1491 }
1492 
1493 #include <ctype.h>
1494 #define LINESIZ 72
1495 char ring[128];
1496 char *endring;
1497 
1498 void
1499 initring(void)
1500 {
1501 	int i;
1502 
1503 	endring = ring;
1504 
1505 	for (i = 0; i <= sizeof ring; ++i)
1506 		if (isprint((unsigned char)i))
1507 			*endring++ = i;
1508 }
1509 
1510 void
1511 chargen_stream(int s, struct servtab *sep)
1512 {
1513 	char *rs;
1514 	int len;
1515 	char text[LINESIZ+2];
1516 
1517 	inetd_setproctitle(sep->se_service, s);
1518 
1519 	if (!endring) {
1520 		initring();
1521 		rs = ring;
1522 	}
1523 
1524 	text[LINESIZ] = '\r';
1525 	text[LINESIZ + 1] = '\n';
1526 	for (rs = ring;;) {
1527 		if ((len = endring - rs) >= LINESIZ)
1528 			memmove(text, rs, LINESIZ);
1529 		else {
1530 			memmove(text, rs, len);
1531 			memmove(text + len, ring, LINESIZ - len);
1532 		}
1533 		if (++rs == endring)
1534 			rs = ring;
1535 		if (write(s, text, sizeof(text)) != sizeof(text))
1536 			break;
1537 	}
1538 	exit(0);
1539 }
1540 
1541 void
1542 chargen_dg(int s, struct servtab *sep)
1543 {
1544 	struct sockaddr_storage ss;
1545 	static char *rs;
1546 	int len;
1547 	socklen_t size;
1548 	char text[LINESIZ+2];
1549 
1550 	if (endring == 0) {
1551 		initring();
1552 		rs = ring;
1553 	}
1554 
1555 	size = sizeof(ss);
1556 	if (recvfrom(s, text, sizeof(text), 0, (struct sockaddr *)&ss,
1557 	    &size) == -1)
1558 		return;
1559 	if (dg_badinput((struct sockaddr *)&ss))
1560 		return;
1561 
1562 	if ((len = endring - rs) >= LINESIZ)
1563 		memmove(text, rs, LINESIZ);
1564 	else {
1565 		memmove(text, rs, len);
1566 		memmove(text + len, ring, LINESIZ - len);
1567 	}
1568 	if (++rs == endring)
1569 		rs = ring;
1570 	text[LINESIZ] = '\r';
1571 	text[LINESIZ + 1] = '\n';
1572 	(void) sendto(s, text, sizeof(text), 0, (struct sockaddr *)&ss, size);
1573 }
1574 
1575 /*
1576  * Return a machine readable date and time, in the form of the
1577  * number of seconds since midnight, Jan 1, 1900.  Since gettimeofday
1578  * returns the number of seconds since midnight, Jan 1, 1970,
1579  * we must add 2208988800 seconds to this figure to make up for
1580  * some seventy years Bell Labs was asleep.
1581  */
1582 u_int32_t
1583 machtime(void)
1584 {
1585 	struct timeval tv;
1586 
1587 	if (gettimeofday(&tv, NULL) == -1)
1588 		return (0L);
1589 
1590 	return (htonl((u_int32_t)tv.tv_sec + 2208988800UL));
1591 }
1592 
1593 void
1594 machtime_stream(int s, struct servtab *sep)
1595 {
1596 	u_int32_t result;
1597 
1598 	result = machtime();
1599 	(void) write(s, &result, sizeof(result));
1600 }
1601 
1602 void
1603 machtime_dg(int s, struct servtab *sep)
1604 {
1605 	u_int32_t result;
1606 	struct sockaddr_storage ss;
1607 	socklen_t size;
1608 
1609 	size = sizeof(ss);
1610 	if (recvfrom(s, &result, sizeof(result), 0,
1611 	    (struct sockaddr *)&ss, &size) == -1)
1612 		return;
1613 	if (dg_badinput((struct sockaddr *)&ss))
1614 		return;
1615 	result = machtime();
1616 	(void) sendto(s, &result, sizeof(result), 0,
1617 	    (struct sockaddr *)&ss, size);
1618 }
1619 
1620 /* Return human-readable time of day */
1621 void
1622 daytime_stream(int s, struct servtab *sep)
1623 {
1624 	char buffer[256];
1625 	time_t clock;
1626 
1627 	clock = time(NULL);
1628 
1629 	(void) snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
1630 	(void) write(s, buffer, strlen(buffer));
1631 }
1632 
1633 /* Return human-readable time of day */
1634 void
1635 daytime_dg(int s, struct servtab *sep)
1636 {
1637 	char buffer[256];
1638 	time_t clock;
1639 	struct sockaddr_storage ss;
1640 	socklen_t size;
1641 
1642 	clock = time(NULL);
1643 
1644 	size = sizeof(ss);
1645 	if (recvfrom(s, buffer, sizeof(buffer), 0, (struct sockaddr *)&ss,
1646 	    &size) == -1)
1647 		return;
1648 	if (dg_badinput((struct sockaddr *)&ss))
1649 		return;
1650 	(void) snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
1651 	(void) sendto(s, buffer, strlen(buffer), 0, (struct sockaddr *)&ss,
1652 	    size);
1653 }
1654 
1655 /*
1656  * print_service:
1657  *	Dump relevant information to stderr
1658  */
1659 void
1660 print_service(char *action, struct servtab *sep)
1661 {
1662 	if (strcmp(sep->se_hostaddr, "*") == 0)
1663 		fprintf(stderr, "%s: %s ", action, sep->se_service);
1664 	else
1665 		fprintf(stderr, "%s: %s:%s ", action, sep->se_hostaddr,
1666 		    sep->se_service);
1667 
1668 	if (isrpcservice(sep))
1669 		fprintf(stderr, "rpcprog=%d, rpcvers=%d/%d, proto=%s,",
1670 		    sep->se_rpcprog, sep->se_rpcversh,
1671 		    sep->se_rpcversl, sep->se_proto);
1672 	else
1673 		fprintf(stderr, "proto=%s,", sep->se_proto);
1674 
1675 	fprintf(stderr,
1676 	    " wait.max=%d.%d user:group=%s:%s builtin=%lx server=%s\n",
1677 	    sep->se_wait, sep->se_max, sep->se_user,
1678 	    sep->se_group ? sep->se_group : "wheel",
1679 	    (long)sep->se_bi, sep->se_server);
1680 }
1681 
1682 void
1683 spawn(int ctrl, short events, void *xsep)
1684 {
1685 	struct servtab *sep = xsep;
1686 	struct passwd *pwd;
1687 	int tmpint, dofork;
1688 	struct group *grp = NULL;
1689 	char buf[50];
1690 	pid_t pid;
1691 
1692 	if (debug)
1693 		fprintf(stderr, "someone wants %s\n", sep->se_service);
1694 
1695 	pid = 0;
1696 	dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
1697 	if (dofork) {
1698 		if (sep->se_count++ == 0)
1699 		    (void)gettimeofday(&sep->se_time, NULL);
1700 		else if (sep->se_count >= sep->se_max) {
1701 			struct timeval now;
1702 
1703 			(void)gettimeofday(&now, NULL);
1704 			if (now.tv_sec - sep->se_time.tv_sec >
1705 			    CNT_INTVL) {
1706 				sep->se_time = now;
1707 				sep->se_count = 1;
1708 			} else {
1709 				if (!sep->se_wait &&
1710 				    sep->se_socktype == SOCK_STREAM)
1711 					close(ctrl);
1712 				if (sep->se_family == AF_INET &&
1713 				    ntohs(sep->se_ctrladdr_in.sin_port) >=
1714 				    IPPORT_RESERVED) {
1715 					/*
1716 					 * Cannot close it -- there are
1717 					 * thieves on the system.
1718 					 * Simply ignore the connection.
1719 					 */
1720 					--sep->se_count;
1721 					return;
1722 				}
1723 				syslog(LOG_ERR,
1724 				    "%s/%s server failing (looping), service terminated",
1725 				    sep->se_service, sep->se_proto);
1726 				if (!sep->se_wait &&
1727 				    sep->se_socktype == SOCK_STREAM)
1728 					close(ctrl);
1729 				event_del(&sep->se_event);
1730 				(void) close(sep->se_fd);
1731 
1732 				sep->se_fd = -1;
1733 				sep->se_count = 0;
1734 				if (!timingout) {
1735 					timingout = 1;
1736 					alarm(RETRYTIME);
1737 				}
1738 				return;
1739 			}
1740 		}
1741 		pid = fork();
1742 	}
1743 	if (pid == -1) {
1744 		syslog(LOG_ERR, "fork: %m");
1745 		if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1746 			close(ctrl);
1747 		sleep(1);
1748 		return;
1749 	}
1750 
1751 	if (pid && sep->se_wait) {
1752 		sep->se_wait = pid;
1753 		event_del(&sep->se_event);
1754 	}
1755 	if (pid == 0) {
1756 		if (sep->se_bi) {
1757 			if (dofork && pledge("stdio inet", NULL) == -1)
1758 				err(1, "pledge");
1759 			(*sep->se_bi->bi_fn)(ctrl, sep);
1760 		} else {
1761 			if ((pwd = getpwnam(sep->se_user)) == NULL) {
1762 				syslog(LOG_ERR,
1763 				    "getpwnam: %s: No such user",
1764 				    sep->se_user);
1765 				if (sep->se_socktype != SOCK_STREAM)
1766 					recv(0, buf, sizeof (buf), 0);
1767 				exit(1);
1768 			}
1769 			if (setsid() <0)
1770 				syslog(LOG_ERR, "%s: setsid: %m",
1771 				    sep->se_service);
1772 			if (sep->se_group &&
1773 			    (grp = getgrnam(sep->se_group)) == NULL) {
1774 				syslog(LOG_ERR,
1775 				    "getgrnam: %s: No such group",
1776 				    sep->se_group);
1777 				if (sep->se_socktype != SOCK_STREAM)
1778 					recv(0, buf, sizeof (buf), 0);
1779 				exit(1);
1780 			}
1781 			if (uid != 0) {
1782 				/* a user running private inetd */
1783 				if (uid != pwd->pw_uid)
1784 					exit(1);
1785 			} else {
1786 				tmpint = LOGIN_SETALL &
1787 				    ~(LOGIN_SETGROUP|LOGIN_SETLOGIN);
1788 				if (pwd->pw_uid)
1789 					tmpint |= LOGIN_SETGROUP|LOGIN_SETLOGIN;
1790 				if (sep->se_group) {
1791 					pwd->pw_gid = grp->gr_gid;
1792 					tmpint |= LOGIN_SETGROUP;
1793 				}
1794 				if (setusercontext(NULL, pwd, pwd->pw_uid,
1795 				    tmpint) == -1) {
1796 					syslog(LOG_ERR,
1797 					    "%s/%s: setusercontext: %m",
1798 					    sep->se_service, sep->se_proto);
1799 					exit(1);
1800 				}
1801 			}
1802 			if (debug)
1803 				fprintf(stderr, "%ld execv %s\n",
1804 				    (long)getpid(), sep->se_server);
1805 			if (ctrl != STDIN_FILENO) {
1806 				dup2(ctrl, STDIN_FILENO);
1807 				close(ctrl);
1808 			}
1809 			dup2(STDIN_FILENO, STDOUT_FILENO);
1810 			dup2(STDIN_FILENO, STDERR_FILENO);
1811 			closelog();
1812 			closefrom(3);
1813 			signal(SIGPIPE, SIG_DFL);
1814 			execv(sep->se_server, sep->se_argv);
1815 			if (sep->se_socktype != SOCK_STREAM)
1816 				recv(0, buf, sizeof (buf), 0);
1817 			syslog(LOG_ERR, "execv %s: %m", sep->se_server);
1818 			exit(1);
1819 		}
1820 	}
1821 	if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
1822 		close(ctrl);
1823 }
1824