xref: /netbsd-src/usr.sbin/faithd/faithd.c (revision 94a96ec4ae423e59922e3eff024d98e7465eb44f)
1 /*	$NetBSD: faithd.c,v 1.36 2013/10/19 17:16:25 christos Exp $	*/
2 /*	$KAME: faithd.c,v 1.62 2003/08/19 21:20:33 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1997 and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * User level translator from IPv6 to IPv4.
35  *
36  * Usage: faithd [<port> <progpath> <arg1(progname)> <arg2> ...]
37  *   e.g. faithd telnet /usr/local/v6/sbin/telnetd telnetd
38  */
39 
40 #include <sys/cdefs.h>
41 #include <sys/param.h>
42 #include <sys/types.h>
43 #include <sys/sysctl.h>
44 #include <sys/socket.h>
45 #include <sys/wait.h>
46 #include <sys/stat.h>
47 #include <sys/time.h>
48 #include <sys/ioctl.h>
49 
50 #include <poll.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <stdarg.h>
54 #include <string.h>
55 #include <syslog.h>
56 #include <unistd.h>
57 #include <errno.h>
58 #include <signal.h>
59 #include <fcntl.h>
60 #include <termios.h>
61 
62 #include <net/if_types.h>
63 #ifdef IFT_FAITH
64 # define USE_ROUTE
65 # include <net/if.h>
66 # include <net/route.h>
67 # include <net/if_dl.h>
68 #endif
69 
70 #include <netinet/in.h>
71 #include <arpa/inet.h>
72 #include <netdb.h>
73 #include <ifaddrs.h>
74 
75 #include "faithd.h"
76 #include "prefix.h"
77 
78 char *serverpath = NULL;
79 char *serverarg[MAXARGV + 1];
80 char logname[BUFSIZ];
81 char procname[BUFSIZ];
82 struct myaddrs {
83 	struct myaddrs *next;
84 	struct sockaddr *addr;
85 };
86 struct myaddrs *myaddrs = NULL;
87 static const char *service;
88 #ifdef USE_ROUTE
89 static int sockfd = 0;
90 #endif
91 int dflag = 0;
92 static int pflag = 0;
93 static int inetd = 0;
94 static char *configfile = NULL;
95 
96 static int inetd_main(int, char **);
97 static int daemon_main(int, char **);
98 static void play_service(int) __dead;
99 static void play_child(int, struct sockaddr *) __dead;
100 static int faith_prefix(struct sockaddr *);
101 static int map6to4(struct sockaddr_in6 *, struct sockaddr_in *);
102 static void sig_child(int);
103 static void sig_terminate(int) __dead;
104 static void start_daemon(void);
105 static void exit_stderr(const char *, ...) __printflike(1, 2) __dead;
106 static void grab_myaddrs(void);
107 static void free_myaddrs(void);
108 static void update_myaddrs(void);
109 static void usage(void) __dead;
110 
111 int
main(int argc,char ** argv)112 main(int argc, char **argv)
113 {
114 
115 	/*
116 	 * Initializing stuff
117 	 */
118 
119 	setprogname(argv[0]);
120 
121 	if (strcmp(getprogname(), "faithd") != 0) {
122 		inetd = 1;
123 		return inetd_main(argc, argv);
124 	} else
125 		return daemon_main(argc, argv);
126 }
127 
128 static int
inetd_main(int argc,char ** argv)129 inetd_main(int argc, char **argv)
130 {
131 	char path[MAXPATHLEN];
132 	struct sockaddr_storage me;
133 	struct sockaddr_storage from;
134 	socklen_t melen, fromlen;
135 	int i;
136 	int error;
137 	const int on = 1;
138 	char sbuf[NI_MAXSERV], snum[NI_MAXSERV];
139 
140 	if (config_load(configfile) < 0 && configfile) {
141 		exit_failure("could not load config file");
142 		/*NOTREACHED*/
143 	}
144 
145 	if (strrchr(argv[0], '/') == NULL)
146 		(void)snprintf(path, sizeof(path), "%s/%s", DEFAULT_DIR,
147 		    argv[0]);
148 	else
149 		(void)snprintf(path, sizeof(path), "%s", argv[0]);
150 
151 #ifdef USE_ROUTE
152 	grab_myaddrs();
153 
154 	sockfd = socket(PF_ROUTE, SOCK_RAW, PF_UNSPEC);
155 	if (sockfd < 0) {
156 		exit_failure("socket(PF_ROUTE): %s", strerror(errno));
157 		/*NOTREACHED*/
158 	}
159 #endif
160 
161 	melen = sizeof(me);
162 	if (getsockname(STDIN_FILENO, (void *)&me, &melen) == -1) {
163 		exit_failure("getsockname: %s", strerror(errno));
164 		/*NOTREACHED*/
165 	}
166 	fromlen = sizeof(from);
167 	if (getpeername(STDIN_FILENO, (void *)&from, &fromlen) == -1) {
168 		exit_failure("getpeername: %s", strerror(errno));
169 		/*NOTREACHED*/
170 	}
171 	if (getnameinfo((void *)&me, melen, NULL, 0,
172 	    sbuf, (socklen_t)sizeof(sbuf), NI_NUMERICHOST) == 0)
173 		service = sbuf;
174 	else
175 		service = DEFAULT_PORT_NAME;
176 	if (getnameinfo((void *)&me, melen, NULL, 0,
177 	    snum, (socklen_t)sizeof(snum), NI_NUMERICHOST) != 0)
178 		(void)snprintf(snum, sizeof(snum), "?");
179 
180 	(void)snprintf(logname, sizeof(logname), "faithd %s", snum);
181 	(void)snprintf(procname, sizeof(procname), "accepting port %s", snum);
182 	openlog(logname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
183 
184 	if (argc >= MAXARGV) {
185 		exit_failure("too many arguments");
186 		/*NOTREACHED*/
187 	}
188 	serverarg[0] = serverpath = path;
189 	for (i = 1; i < argc; i++)
190 		serverarg[i] = argv[i];
191 	serverarg[i] = NULL;
192 
193 	error = setsockopt(STDIN_FILENO, SOL_SOCKET, SO_OOBINLINE, &on,
194 	    (socklen_t)sizeof(on));
195 	if (error < 0) {
196 		exit_failure("setsockopt(SO_OOBINLINE): %s", strerror(errno));
197 		/*NOTREACHED*/
198 	}
199 
200 	play_child(STDIN_FILENO, (void *)&from);
201 	exit_failure("should not reach here");
202 	return 0;	/*dummy!*/
203 }
204 
205 static int
daemon_main(int argc,char ** argv)206 daemon_main(int argc, char **argv)
207 {
208 	struct addrinfo hints, *res;
209 	int s_wld, error, i, serverargc, on = 1;
210 	int family = AF_INET6;
211 	int c;
212 
213 	while ((c = getopt(argc, argv, "df:p")) != -1) {
214 		switch (c) {
215 		case 'd':
216 			dflag++;
217 			break;
218 		case 'f':
219 			configfile = optarg;
220 			break;
221 		case 'p':
222 			pflag++;
223 			break;
224 		default:
225 			usage();
226 			/*NOTREACHED*/
227 		}
228 	}
229 	argc -= optind;
230 	argv += optind;
231 
232 	if (config_load(configfile) < 0 && configfile) {
233 		exit_failure("could not load config file");
234 		/*NOTREACHED*/
235 	}
236 
237 
238 #ifdef USE_ROUTE
239 	grab_myaddrs();
240 #endif
241 
242 	switch (argc) {
243 	case 0:
244 		usage();
245 		/*NOTREACHED*/
246 	default:
247 		serverargc = argc - NUMARG;
248 		if (serverargc >= MAXARGV)
249 			exit_stderr("too many arguments");
250 
251 		serverpath = strdup(argv[NUMPRG]);
252 		if (!serverpath)
253 			exit_stderr("not enough core");
254 		for (i = 0; i < serverargc; i++) {
255 			serverarg[i] = strdup(argv[i + NUMARG]);
256 			if (!serverarg[i])
257 				exit_stderr("not enough core");
258 		}
259 		serverarg[i] = NULL;
260 		/*FALLTHROUGH*/
261 	case 1:	/* no local service */
262 		service = argv[NUMPRT];
263 		break;
264 	}
265 
266 	start_daemon();
267 
268 	/*
269 	 * Opening wild card socket for this service.
270 	 */
271 
272 	memset(&hints, 0, sizeof(hints));
273 	hints.ai_flags = AI_PASSIVE;
274 	hints.ai_family = family;
275 	hints.ai_socktype = SOCK_STREAM;
276 	hints.ai_protocol = IPPROTO_TCP;	/* SCTP? */
277 	error = getaddrinfo(NULL, service, &hints, &res);
278 	if (error)
279 		exit_failure("getaddrinfo: %s", gai_strerror(error));
280 
281 	s_wld = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
282 	if (s_wld == -1)
283 		exit_failure("socket: %s", strerror(errno));
284 
285 #ifdef IPV6_FAITH
286 	if (res->ai_family == AF_INET6) {
287 		error = setsockopt(s_wld, IPPROTO_IPV6, IPV6_FAITH, &on,
288 		    (socklen_t)sizeof(on));
289 		if (error == -1)
290 			exit_failure("setsockopt(IPV6_FAITH): %s",
291 			    strerror(errno));
292 	}
293 #endif
294 
295 	error = setsockopt(s_wld, SOL_SOCKET, SO_REUSEADDR, &on,
296 	    (socklen_t)sizeof(on));
297 	if (error == -1)
298 		exit_failure("setsockopt(SO_REUSEADDR): %s", strerror(errno));
299 
300 	error = setsockopt(s_wld, SOL_SOCKET, SO_OOBINLINE, &on,
301 	    (socklen_t)sizeof(on));
302 	if (error == -1)
303 		exit_failure("setsockopt(SO_OOBINLINE): %s", strerror(errno));
304 
305 #ifdef IPV6_V6ONLY
306 	error = setsockopt(s_wld, IPPROTO_IPV6, IPV6_V6ONLY, &on,
307 	    (socklen_t)sizeof(on));
308 	if (error == -1)
309 		exit_failure("setsockopt(IPV6_V6ONLY): %s", strerror(errno));
310 #endif
311 
312 	error = bind(s_wld, (struct sockaddr *)res->ai_addr, res->ai_addrlen);
313 	if (error == -1)
314 		exit_failure("bind: %s", strerror(errno));
315 
316 	error = listen(s_wld, 5);
317 	if (error == -1)
318 		exit_failure("listen: %s", strerror(errno));
319 
320 #ifdef USE_ROUTE
321 	sockfd = socket(PF_ROUTE, SOCK_RAW, PF_UNSPEC);
322 	if (sockfd < 0) {
323 		exit_failure("socket(PF_ROUTE): %s", strerror(errno));
324 		/*NOTREACHED*/
325 	}
326 #endif
327 
328 	/*
329 	 * Everything is OK.
330 	 */
331 
332 	(void)snprintf(logname, sizeof(logname), "faithd %s", service);
333 	(void)snprintf(procname, sizeof(procname), "accepting port %s", service);
334 	openlog(logname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
335 	syslog(LOG_INFO, "Staring faith daemon for %s port", service);
336 
337 	play_service(s_wld);
338 	return 1;
339 }
340 
341 static void
play_service(int s_wld)342 play_service(int s_wld)
343 {
344 	struct sockaddr_storage srcaddr;
345 	socklen_t len;
346 	int s_src;
347 	pid_t child_pid;
348 	struct pollfd pfd[2];
349 	int error;
350 
351 	/*
352 	 * Wait, accept, fork, faith....
353 	 */
354 again:
355 	setproctitle("%s", procname);
356 
357 	pfd[0].fd = s_wld;
358 	pfd[0].events = POLLIN;
359 	pfd[1].fd = -1;
360 	pfd[1].revents = 0;
361 #ifdef USE_ROUTE
362 	if (sockfd) {
363 		pfd[1].fd = sockfd;
364 		pfd[1].events = POLLIN;
365 	}
366 #endif
367 
368 	error = poll(pfd, (unsigned int)(sizeof(pfd) / sizeof(pfd[0])), INFTIM);
369 	if (error < 0) {
370 		if (errno == EINTR)
371 			goto again;
372 		exit_failure("select: %s", strerror(errno));
373 		/*NOTREACHED*/
374 	}
375 
376 #ifdef USE_ROUTE
377 	if (pfd[1].revents & POLLIN)
378 	{
379 		update_myaddrs();
380 	}
381 #endif
382 	if (pfd[0].revents & POLLIN)
383 	{
384 		len = sizeof(srcaddr);
385 		s_src = accept(s_wld, (void *)&srcaddr, &len);
386 		if (s_src < 0) {
387 			if (errno == ECONNABORTED)
388 				goto again;
389 			exit_failure("socket: %s", strerror(errno));
390 			/*NOTREACHED*/
391 		}
392 		if (srcaddr.ss_family == AF_INET6 &&
393 		    IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)(void *)&srcaddr)->sin6_addr)) {
394 			(void)close(s_src);
395 			syslog(LOG_ERR, "connection from IPv4 mapped address?");
396 			goto again;
397 		}
398 
399 		child_pid = fork();
400 
401 		if (child_pid == 0) {
402 			/* child process */
403 			(void)close(s_wld);
404 			closelog();
405 			openlog(logname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
406 			play_child(s_src, (void *)&srcaddr);
407 			exit_failure("should never reach here");
408 			/*NOTREACHED*/
409 		} else {
410 			/* parent process */
411 			(void)close(s_src);
412 			if (child_pid == -1)
413 				syslog(LOG_ERR, "can't fork");
414 		}
415 	}
416 	goto again;
417 }
418 
419 static void
play_child(int s_src,struct sockaddr * srcaddr)420 play_child(int s_src, struct sockaddr *srcaddr)
421 {
422 	struct sockaddr_storage dstaddr6;
423 	struct sockaddr_storage dstaddr4;
424 	char src[NI_MAXHOST];
425 	char dst6[NI_MAXHOST];
426 	char dst4[NI_MAXHOST];
427 	socklen_t len = sizeof(dstaddr6);
428 	int s_dst, error, hport, nresvport, on = 1;
429 	struct timeval tv;
430 	struct sockaddr *sa4;
431 	const struct config *conf;
432 
433 	tv.tv_sec = 1;
434 	tv.tv_usec = 0;
435 
436 	(void)getnameinfo(srcaddr, (socklen_t)srcaddr->sa_len,
437 	    src, (socklen_t)sizeof(src), NULL, 0, NI_NUMERICHOST);
438 	syslog(LOG_INFO, "accepted a client from %s", src);
439 
440 	error = getsockname(s_src, (void *)&dstaddr6, &len);
441 	if (error == -1) {
442 		exit_failure("getsockname: %s", strerror(errno));
443 		/*NOTREACHED*/
444 	}
445 
446 	(void)getnameinfo((void *)&dstaddr6, len,
447 	    dst6, (socklen_t)sizeof(dst6), NULL, 0, NI_NUMERICHOST);
448 	syslog(LOG_INFO, "the client is connecting to %s", dst6);
449 
450 	if (!faith_prefix((void *)&dstaddr6)) {
451 		if (serverpath) {
452 			/*
453 			 * Local service
454 			 */
455 			syslog(LOG_INFO, "executing local %s", serverpath);
456 			if (!inetd) {
457 				(void)dup2(s_src, 0);
458 				(void)close(s_src);
459 				(void)dup2(0, 1);
460 				(void)dup2(0, 2);
461 			}
462 			(void)execv(serverpath, serverarg);
463 			syslog(LOG_ERR, "execv %s: %s", serverpath,
464 			    strerror(errno));
465 			_exit(EXIT_FAILURE);
466 		} else {
467 			(void)close(s_src);
468 			exit_success("no local service for %s", service);
469 		}
470 	}
471 
472 	/*
473 	 * Act as a translator
474 	 */
475 
476 	switch (((struct sockaddr *)(void *)&dstaddr6)->sa_family) {
477 	case AF_INET6:
478 		if (!map6to4((struct sockaddr_in6 *)(void *)&dstaddr6,
479 		    (struct sockaddr_in *)(void *)&dstaddr4)) {
480 			(void)close(s_src);
481 			exit_failure("map6to4 failed");
482 			/*NOTREACHED*/
483 		}
484 		syslog(LOG_INFO, "translating from v6 to v4");
485 		break;
486 	default:
487 		(void)close(s_src);
488 		exit_failure("family not supported");
489 		/*NOTREACHED*/
490 	}
491 
492 	sa4 = (void *)&dstaddr4;
493 	(void)getnameinfo(sa4, (socklen_t)sa4->sa_len,
494 	    dst4, (socklen_t)sizeof(dst4), NULL, 0, NI_NUMERICHOST);
495 
496 	conf = config_match(srcaddr, sa4);
497 	if (!conf || !conf->permit) {
498 		(void)close(s_src);
499 		if (conf) {
500 			exit_failure("translation to %s not permitted for %s",
501 			    dst4, prefix_string(&conf->match));
502 			/*NOTREACHED*/
503 		} else {
504 			exit_failure("translation to %s not permitted", dst4);
505 			/*NOTREACHED*/
506 		}
507 	}
508 
509 	syslog(LOG_INFO, "the translator is connecting to %s", dst4);
510 
511 	setproctitle("port %s, %s -> %s", service, src, dst4);
512 
513 	if (sa4->sa_family == AF_INET6)
514 		hport = ntohs(((struct sockaddr_in6 *)(void *)&dstaddr4)->sin6_port);
515 	else /* AF_INET */
516 		hport = ntohs(((struct sockaddr_in *)(void *)&dstaddr4)->sin_port);
517 
518 	if (pflag)
519 		s_dst = rresvport_af(&nresvport, sa4->sa_family);
520 	else
521 		s_dst = socket(sa4->sa_family, SOCK_STREAM, 0);
522 	if (s_dst < 0) {
523 		exit_failure("socket: %s", strerror(errno));
524 		/*NOTREACHED*/
525 	}
526 
527 	if (conf->src.a.ss_family) {
528 		if (bind(s_dst, (const void*)&conf->src.a,
529 		    (socklen_t)conf->src.a.ss_len) < 0) {
530 			exit_failure("bind: %s", strerror(errno));
531 			/*NOTREACHED*/
532 		}
533 	}
534 
535 	error = setsockopt(s_dst, SOL_SOCKET, SO_OOBINLINE, &on,
536 	    (socklen_t)sizeof(on));
537 	if (error < 0) {
538 		exit_failure("setsockopt(SO_OOBINLINE): %s", strerror(errno));
539 		/*NOTREACHED*/
540 	}
541 
542 	error = setsockopt(s_src, SOL_SOCKET, SO_SNDTIMEO, &tv,
543 	    (socklen_t)sizeof(tv));
544 	if (error < 0) {
545 		exit_failure("setsockopt(SO_SNDTIMEO): %s", strerror(errno));
546 		/*NOTREACHED*/
547 	}
548 	error = setsockopt(s_dst, SOL_SOCKET, SO_SNDTIMEO, &tv,
549 	    (socklen_t)sizeof(tv));
550 	if (error < 0) {
551 		exit_failure("setsockopt(SO_SNDTIMEO): %s", strerror(errno));
552 		/*NOTREACHED*/
553 	}
554 
555 	error = connect(s_dst, sa4, (socklen_t)sa4->sa_len);
556 	if (error < 0) {
557 		exit_failure("connect: %s", strerror(errno));
558 		/*NOTREACHED*/
559 	}
560 
561 	switch (hport) {
562 	case FTP_PORT:
563 		ftp_relay(s_src, s_dst);
564 		break;
565 	default:
566 		tcp_relay(s_src, s_dst, service);
567 		break;
568 	}
569 
570 	/* NOTREACHED */
571 }
572 
573 /* 0: non faith, 1: faith */
574 static int
faith_prefix(struct sockaddr * dst)575 faith_prefix(struct sockaddr *dst)
576 {
577 #ifndef USE_ROUTE
578 	int mib[4], size;
579 	struct in6_addr faith_prefix;
580 	struct sockaddr_in6 *dst6 = (struct sockaddr_in *)dst;
581 
582 	if (dst->sa_family != AF_INET6)
583 		return 0;
584 
585 	mib[0] = CTL_NET;
586 	mib[1] = PF_INET6;
587 	mib[2] = IPPROTO_IPV6;
588 	mib[3] = IPV6CTL_FAITH_PREFIX;
589 	size = sizeof(struct in6_addr);
590 	if (sysctl(mib, 4, &faith_prefix, &size, NULL, 0) < 0) {
591 		exit_failure("sysctl: %s", strerror(errno));
592 		/*NOTREACHED*/
593 	}
594 
595 	return memcmp(dst, &faith_prefix,
596 	    sizeof(struct in6_addr) - sizeof(struct in_addr)) == 0;
597 #else
598 	struct myaddrs *p;
599 	struct sockaddr_in6 *sin6;
600 	struct sockaddr_in *sin4;
601 	struct sockaddr_in6 *dst6;
602 	struct sockaddr_in *dst4;
603 	struct sockaddr_in dstmap;
604 
605 	dst6 = (void *)dst;
606 	if (dst->sa_family == AF_INET6
607 	 && IN6_IS_ADDR_V4MAPPED(&dst6->sin6_addr)) {
608 		/* ugly... */
609 		memset(&dstmap, 0, sizeof(dstmap));
610 		dstmap.sin_family = AF_INET;
611 		dstmap.sin_len = sizeof(dstmap);
612 		memcpy(&dstmap.sin_addr, &dst6->sin6_addr.s6_addr[12],
613 			sizeof(dstmap.sin_addr));
614 		dst = (void *)&dstmap;
615 	}
616 
617 	dst6 = (void *)dst;
618 	dst4 = (void *)dst;
619 
620 	for (p = myaddrs; p; p = p->next) {
621 		sin6 = (void *)p->addr;
622 		sin4 = (void *)p->addr;
623 
624 		if (p->addr->sa_len != dst->sa_len
625 		 || p->addr->sa_family != dst->sa_family)
626 			continue;
627 
628 		switch (dst->sa_family) {
629 		case AF_INET6:
630 			if (sin6->sin6_scope_id == dst6->sin6_scope_id
631 			 && IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &dst6->sin6_addr))
632 				return 0;
633 			break;
634 		case AF_INET:
635 			if (sin4->sin_addr.s_addr == dst4->sin_addr.s_addr)
636 				return 0;
637 			break;
638 		}
639 	}
640 	return 1;
641 #endif
642 }
643 
644 /* 0: non faith, 1: faith */
645 static int
map6to4(struct sockaddr_in6 * dst6,struct sockaddr_in * dst4)646 map6to4(struct sockaddr_in6 *dst6, struct sockaddr_in *dst4)
647 {
648 	memset(dst4, 0, sizeof(*dst4));
649 	dst4->sin_len = sizeof(*dst4);
650 	dst4->sin_family = AF_INET;
651 	dst4->sin_port = dst6->sin6_port;
652 	memcpy(&dst4->sin_addr, &dst6->sin6_addr.s6_addr[12],
653 		sizeof(dst4->sin_addr));
654 
655 	if (dst4->sin_addr.s_addr == INADDR_ANY
656 	 || dst4->sin_addr.s_addr == INADDR_BROADCAST
657 	 || IN_MULTICAST(ntohl(dst4->sin_addr.s_addr)))
658 		return 0;
659 
660 	return 1;
661 }
662 
663 
664 static void
665 /*ARGSUSED*/
sig_child(int sig)666 sig_child(int sig)
667 {
668 	int status;
669 	pid_t pid;
670 
671 	while ((pid = wait3(&status, WNOHANG, (struct rusage *)0)) > 0)
672 		if (WEXITSTATUS(status))
673 			syslog(LOG_WARNING, "child %ld exit status 0x%x",
674 			    (long)pid, status);
675 }
676 
677 static void
678 /*ARGSUSED*/
sig_terminate(int sig)679 sig_terminate(int sig)
680 {
681 	syslog(LOG_INFO, "Terminating faith daemon");
682 	exit(EXIT_SUCCESS);
683 }
684 
685 static void
start_daemon(void)686 start_daemon(void)
687 {
688 #ifdef SA_NOCLDWAIT
689 	struct sigaction sa;
690 #endif
691 
692 	if (daemon(0, 0) == -1)
693 		exit_stderr("daemon: %s", strerror(errno));
694 
695 #ifdef SA_NOCLDWAIT
696 	(void)memset(&sa, 0, sizeof(sa));
697 	sa.sa_handler = sig_child;
698 	sa.sa_flags = SA_NOCLDWAIT;
699 	(void)sigemptyset(&sa.sa_mask);
700 	(void)sigaction(SIGCHLD, &sa, (struct sigaction *)0);
701 #else
702 	if (signal(SIGCHLD, sig_child) == SIG_ERR) {
703 		exit_failure("signal CHLD: %s", strerror(errno));
704 		/*NOTREACHED*/
705 	}
706 #endif
707 
708 	if (signal(SIGTERM, sig_terminate) == SIG_ERR) {
709 		exit_failure("signal TERM: %s", strerror(errno));
710 		/*NOTREACHED*/
711 	}
712 }
713 
714 static void
exit_stderr(const char * fmt,...)715 exit_stderr(const char *fmt, ...)
716 {
717 	va_list ap;
718 
719 	va_start(ap, fmt);
720 	(void)fprintf(stderr, "%s: ", getprogname());
721 	(void)vfprintf(stderr, fmt, ap);
722 	va_end(ap);
723 	exit(EXIT_FAILURE);
724 }
725 
726 void
exit_failure(const char * fmt,...)727 exit_failure(const char *fmt, ...)
728 {
729 	va_list ap;
730 
731 	va_start(ap, fmt);
732 	vsyslog(LOG_ERR, fmt, ap);
733 	va_end(ap);
734 	exit(EXIT_FAILURE);
735 }
736 
737 void
exit_success(const char * fmt,...)738 exit_success(const char *fmt, ...)
739 {
740 	va_list ap;
741 
742 	va_start(ap, fmt);
743 	vsyslog(LOG_INFO, fmt, ap);
744 	va_end(ap);
745 	exit(EXIT_SUCCESS);
746 }
747 
748 #ifdef USE_ROUTE
749 static void
grab_myaddrs(void)750 grab_myaddrs(void)
751 {
752 	struct ifaddrs *ifap, *ifa;
753 	struct myaddrs *p;
754 
755 	if (getifaddrs(&ifap) != 0) {
756 		exit_failure("getifaddrs");
757 		/*NOTREACHED*/
758 	}
759 
760 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
761 		switch (ifa->ifa_addr->sa_family) {
762 		case AF_INET:
763 		case AF_INET6:
764 			break;
765 		default:
766 			continue;
767 		}
768 
769 		p = (struct myaddrs *)malloc(sizeof(struct myaddrs) +
770 		    ifa->ifa_addr->sa_len);
771 		if (!p) {
772 			exit_failure("not enough core");
773 			/*NOTREACHED*/
774 		}
775 		memcpy(p + 1, ifa->ifa_addr, ifa->ifa_addr->sa_len);
776 		p->next = myaddrs;
777 		p->addr = (void *)(p + 1);
778 		if (ifa->ifa_addr->sa_family == AF_INET6) {
779 			struct sockaddr_in6 *sin6 = (void *)p->addr;
780 			inet6_getscopeid(sin6, INET6_IS_ADDR_LINKLOCAL|
781 				INET6_IS_ADDR_SITELOCAL);
782 		}
783 		myaddrs = p;
784 		if (dflag) {
785 			char hbuf[NI_MAXHOST];
786 			(void)getnameinfo(p->addr, (socklen_t)p->addr->sa_len,
787 			    hbuf, (socklen_t)sizeof(hbuf), NULL, 0,
788 			    NI_NUMERICHOST);
789 			syslog(LOG_INFO, "my interface: %s %s", hbuf,
790 			    ifa->ifa_name);
791 		}
792 	}
793 
794 	freeifaddrs(ifap);
795 }
796 
797 static void
free_myaddrs(void)798 free_myaddrs(void)
799 {
800 	struct myaddrs *p, *q;
801 
802 	p = myaddrs;
803 	while (p) {
804 		q = p->next;
805 		free(p);
806 		p = q;
807 	}
808 	myaddrs = NULL;
809 }
810 
811 static void
update_myaddrs(void)812 update_myaddrs(void)
813 {
814 	char msg[BUFSIZ];
815 	ssize_t len;
816 	struct rt_msghdr *rtm;
817 
818 	len = read(sockfd, msg, sizeof(msg));
819 	if (len < 0) {
820 		syslog(LOG_ERR, "read(PF_ROUTE) failed");
821 		return;
822 	}
823 	rtm = (void *)msg;
824 	if (len < 4 || len < rtm->rtm_msglen) {
825 		syslog(LOG_ERR, "read(PF_ROUTE) short read");
826 		return;
827 	}
828 	if (rtm->rtm_version != RTM_VERSION) {
829 		syslog(LOG_ERR, "routing socket version mismatch");
830 		(void)close(sockfd);
831 		sockfd = 0;
832 		return;
833 	}
834 	switch (rtm->rtm_type) {
835 	case RTM_NEWADDR:
836 	case RTM_DELADDR:
837 	case RTM_IFINFO:
838 		break;
839 	default:
840 		return;
841 	}
842 	/* XXX more filters here? */
843 
844 	syslog(LOG_INFO, "update interface address list");
845 	free_myaddrs();
846 	grab_myaddrs();
847 }
848 #endif /*USE_ROUTE*/
849 
850 static void
usage(void)851 usage(void)
852 {
853 	(void)fprintf(stderr,
854 	    "Usage: %s [-dp] [-f conf] service [serverpath [serverargs]]\n",
855 	    getprogname());
856 	exit(0);
857 }
858