xref: /openbsd/usr.sbin/rad/rad.c (revision 097a140d)
1 /*	$OpenBSD: rad.c,v 1.27 2021/02/27 10:35:20 florian Exp $	*/
2 
3 /*
4  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
5  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
6  * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
7  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
8  *
9  * Permission to use, copy, modify, and distribute this software for any
10  * purpose with or without fee is hereby granted, provided that the above
11  * copyright notice and this permission notice appear in all copies.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
14  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
15  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
16  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
18  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
19  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20  */
21 #include <sys/types.h>
22 #include <sys/queue.h>
23 #include <sys/socket.h>
24 #include <sys/syslog.h>
25 #include <sys/uio.h>
26 #include <sys/wait.h>
27 
28 #include <netinet/in.h>
29 #include <net/if.h>
30 #include <net/route.h>
31 #include <netinet/in.h>
32 #include <netinet/if_ether.h>
33 #include <netinet6/in6_var.h>
34 #include <netinet/icmp6.h>
35 
36 #include <err.h>
37 #include <errno.h>
38 #include <event.h>
39 #include <fcntl.h>
40 #include <imsg.h>
41 #include <netdb.h>
42 #include <pwd.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <signal.h>
47 #include <unistd.h>
48 
49 #include "log.h"
50 #include "rad.h"
51 #include "frontend.h"
52 #include "engine.h"
53 #include "control.h"
54 
55 enum rad_process {
56 	PROC_MAIN,
57 	PROC_ENGINE,
58 	PROC_FRONTEND
59 };
60 
61 __dead void	usage(void);
62 __dead void	main_shutdown(void);
63 
64 void	main_sig_handler(int, short, void *);
65 
66 static pid_t	start_child(enum rad_process, char *, int, int, int);
67 
68 void	main_dispatch_frontend(int, short, void *);
69 void	main_dispatch_engine(int, short, void *);
70 void	open_icmp6sock(int);
71 
72 static int	main_imsg_send_ipc_sockets(struct imsgbuf *, struct imsgbuf *);
73 static int	main_imsg_send_config(struct rad_conf *);
74 
75 int	main_reload(void);
76 int	main_sendboth(enum imsg_type, void *, uint16_t);
77 
78 void	in6_prefixlen2mask(struct in6_addr *, int len);
79 
80 struct rad_conf		*main_conf;
81 static struct imsgev	*iev_frontend;
82 static struct imsgev	*iev_engine;
83 char			*conffile;
84 pid_t			 frontend_pid;
85 pid_t			 engine_pid;
86 uint32_t		 cmd_opts;
87 
88 void
89 main_sig_handler(int sig, short event, void *arg)
90 {
91 	/*
92 	 * Normal signal handler rules don't apply because libevent
93 	 * decouples for us.
94 	 */
95 
96 	switch (sig) {
97 	case SIGTERM:
98 	case SIGINT:
99 		main_shutdown();
100 		break;
101 	case SIGHUP:
102 		if (main_reload() == -1)
103 			log_warnx("configuration reload failed");
104 		else
105 			log_debug("configuration reloaded");
106 		break;
107 	default:
108 		fatalx("unexpected signal");
109 	}
110 }
111 
112 __dead void
113 usage(void)
114 {
115 	extern char *__progname;
116 
117 	fprintf(stderr, "usage: %s [-dnv] [-f file] [-s socket]\n",
118 	    __progname);
119 	exit(1);
120 }
121 
122 int
123 main(int argc, char *argv[])
124 {
125 	struct event		 ev_sigint, ev_sigterm, ev_sighup;
126 	int			 ch;
127 	int			 debug = 0, engine_flag = 0, frontend_flag = 0;
128 	char			*saved_argv0;
129 	int			 pipe_main2frontend[2];
130 	int			 pipe_main2engine[2];
131 	int			 frontend_routesock, rtfilter;
132 	int			 rtable_any = RTABLE_ANY;
133 	int			 control_fd;
134 	char			*csock;
135 
136 	conffile = _PATH_CONF_FILE;
137 	csock = _PATH_RAD_SOCKET;
138 
139 	log_init(1, LOG_DAEMON);	/* Log to stderr until daemonized. */
140 	log_setverbose(1);
141 
142 	saved_argv0 = argv[0];
143 	if (saved_argv0 == NULL)
144 		saved_argv0 = "rad";
145 
146 	while ((ch = getopt(argc, argv, "dEFf:ns:v")) != -1) {
147 		switch (ch) {
148 		case 'd':
149 			debug = 1;
150 			break;
151 		case 'E':
152 			engine_flag = 1;
153 			break;
154 		case 'F':
155 			frontend_flag = 1;
156 			break;
157 		case 'f':
158 			conffile = optarg;
159 			break;
160 		case 'n':
161 			cmd_opts |= OPT_NOACTION;
162 			break;
163 		case 's':
164 			csock = optarg;
165 			break;
166 		case 'v':
167 			if (cmd_opts & OPT_VERBOSE)
168 				cmd_opts |= OPT_VERBOSE2;
169 			cmd_opts |= OPT_VERBOSE;
170 			break;
171 		default:
172 			usage();
173 		}
174 	}
175 
176 	argc -= optind;
177 	argv += optind;
178 	if (argc > 0 || (engine_flag && frontend_flag))
179 		usage();
180 
181 	if (engine_flag)
182 		engine(debug, cmd_opts & OPT_VERBOSE);
183 	else if (frontend_flag)
184 		frontend(debug, cmd_opts & OPT_VERBOSE);
185 
186 	/* parse config file */
187 	if ((main_conf = parse_config(conffile)) == NULL) {
188 		exit(1);
189 	}
190 
191 	if (cmd_opts & OPT_NOACTION) {
192 		if (cmd_opts & OPT_VERBOSE)
193 			print_config(main_conf);
194 		else
195 			fprintf(stderr, "configuration OK\n");
196 		exit(0);
197 	}
198 
199 	/* Check for root privileges. */
200 	if (geteuid())
201 		errx(1, "need root privileges");
202 
203 	/* Check for assigned daemon user */
204 	if (getpwnam(RAD_USER) == NULL)
205 		errx(1, "unknown user %s", RAD_USER);
206 
207 	log_init(debug, LOG_DAEMON);
208 	log_setverbose(cmd_opts & OPT_VERBOSE);
209 
210 	if (!debug)
211 		daemon(1, 0);
212 
213 	log_info("startup");
214 
215 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
216 	    PF_UNSPEC, pipe_main2frontend) == -1)
217 		fatal("main2frontend socketpair");
218 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
219 	    PF_UNSPEC, pipe_main2engine) == -1)
220 		fatal("main2engine socketpair");
221 
222 	/* Start children. */
223 	engine_pid = start_child(PROC_ENGINE, saved_argv0, pipe_main2engine[1],
224 	    debug, cmd_opts & OPT_VERBOSE);
225 	frontend_pid = start_child(PROC_FRONTEND, saved_argv0,
226 	    pipe_main2frontend[1], debug, cmd_opts & OPT_VERBOSE);
227 
228 	log_procinit("main");
229 
230 	event_init();
231 
232 	/* Setup signal handler. */
233 	signal_set(&ev_sigint, SIGINT, main_sig_handler, NULL);
234 	signal_set(&ev_sigterm, SIGTERM, main_sig_handler, NULL);
235 	signal_set(&ev_sighup, SIGHUP, main_sig_handler, NULL);
236 	signal_add(&ev_sigint, NULL);
237 	signal_add(&ev_sigterm, NULL);
238 	signal_add(&ev_sighup, NULL);
239 	signal(SIGPIPE, SIG_IGN);
240 
241 	/* Setup pipes to children. */
242 
243 	if ((iev_frontend = malloc(sizeof(struct imsgev))) == NULL ||
244 	    (iev_engine = malloc(sizeof(struct imsgev))) == NULL)
245 		fatal(NULL);
246 	imsg_init(&iev_frontend->ibuf, pipe_main2frontend[0]);
247 	iev_frontend->handler = main_dispatch_frontend;
248 	imsg_init(&iev_engine->ibuf, pipe_main2engine[0]);
249 	iev_engine->handler = main_dispatch_engine;
250 
251 	/* Setup event handlers for pipes to engine & frontend. */
252 	iev_frontend->events = EV_READ;
253 	event_set(&iev_frontend->ev, iev_frontend->ibuf.fd,
254 	    iev_frontend->events, iev_frontend->handler, iev_frontend);
255 	event_add(&iev_frontend->ev, NULL);
256 
257 	iev_engine->events = EV_READ;
258 	event_set(&iev_engine->ev, iev_engine->ibuf.fd, iev_engine->events,
259 	    iev_engine->handler, iev_engine);
260 	event_add(&iev_engine->ev, NULL);
261 
262 	if (main_imsg_send_ipc_sockets(&iev_frontend->ibuf, &iev_engine->ibuf))
263 		fatal("could not establish imsg links");
264 
265 	if ((frontend_routesock = socket(AF_ROUTE, SOCK_RAW | SOCK_CLOEXEC,
266 	    AF_INET6)) == -1)
267 		fatal("route socket");
268 
269 	rtfilter = ROUTE_FILTER(RTM_IFINFO) | ROUTE_FILTER(RTM_NEWADDR) |
270 	    ROUTE_FILTER(RTM_DELADDR) | ROUTE_FILTER(RTM_CHGADDRATTR);
271 	if (setsockopt(frontend_routesock, AF_ROUTE, ROUTE_MSGFILTER,
272 	    &rtfilter, sizeof(rtfilter)) == -1)
273 		fatal("setsockopt(ROUTE_MSGFILTER)");
274 	if (setsockopt(frontend_routesock, AF_ROUTE, ROUTE_TABLEFILTER,
275 	    &rtable_any, sizeof(rtable_any)) == -1)
276 		fatal("setsockopt(ROUTE_TABLEFILTER)");
277 
278 	if ((control_fd = control_init(csock)) == -1)
279 		fatalx("control socket setup failed");
280 
281 	main_imsg_compose_frontend(IMSG_ROUTESOCK, frontend_routesock,
282 	    NULL, 0);
283 	main_imsg_compose_frontend(IMSG_CONTROLFD, control_fd, NULL, 0);
284 	main_imsg_send_config(main_conf);
285 
286 	if (pledge("stdio inet rpath sendfd mcast wroute", NULL) == -1)
287 		fatal("pledge");
288 
289 	main_imsg_compose_frontend(IMSG_STARTUP, -1, NULL, 0);
290 
291 	event_dispatch();
292 
293 	main_shutdown();
294 	return (0);
295 }
296 
297 __dead void
298 main_shutdown(void)
299 {
300 	pid_t	 pid;
301 	int	 status;
302 
303 	/* Close pipes. */
304 	msgbuf_clear(&iev_frontend->ibuf.w);
305 	close(iev_frontend->ibuf.fd);
306 	msgbuf_clear(&iev_engine->ibuf.w);
307 	close(iev_engine->ibuf.fd);
308 
309 	config_clear(main_conf);
310 
311 	log_debug("waiting for children to terminate");
312 	do {
313 		pid = wait(&status);
314 		if (pid == -1) {
315 			if (errno != EINTR && errno != ECHILD)
316 				fatal("wait");
317 		} else if (WIFSIGNALED(status))
318 			log_warnx("%s terminated; signal %d",
319 			    (pid == engine_pid) ? "engine" :
320 			    "frontend", WTERMSIG(status));
321 	} while (pid != -1 || (pid == -1 && errno == EINTR));
322 
323 	free(iev_frontend);
324 	free(iev_engine);
325 
326 	log_info("terminating");
327 	exit(0);
328 }
329 
330 static pid_t
331 start_child(enum rad_process p, char *argv0, int fd, int debug, int verbose)
332 {
333 	char	*argv[6];
334 	int	 argc = 0;
335 	pid_t	 pid;
336 
337 	switch (pid = fork()) {
338 	case -1:
339 		fatal("cannot fork");
340 	case 0:
341 		break;
342 	default:
343 		close(fd);
344 		return (pid);
345 	}
346 
347 	if (fd != 3) {
348 		if (dup2(fd, 3) == -1)
349 			fatal("cannot setup imsg fd");
350 	} else if (fcntl(fd, F_SETFD, 0) == -1)
351 		fatal("cannot setup imsg fd");
352 
353 	argv[argc++] = argv0;
354 	switch (p) {
355 	case PROC_MAIN:
356 		fatalx("Can not start main process");
357 	case PROC_ENGINE:
358 		argv[argc++] = "-E";
359 		break;
360 	case PROC_FRONTEND:
361 		argv[argc++] = "-F";
362 		break;
363 	}
364 	if (debug)
365 		argv[argc++] = "-d";
366 	if (verbose)
367 		argv[argc++] = "-v";
368 	argv[argc++] = NULL;
369 
370 	execvp(argv0, argv);
371 	fatal("execvp");
372 }
373 
374 void
375 main_dispatch_frontend(int fd, short event, void *bula)
376 {
377 	struct imsgev		*iev = bula;
378 	struct imsgbuf		*ibuf;
379 	struct imsg		 imsg;
380 	ssize_t			 n;
381 	int			 shut = 0, verbose;
382 	int			 rdomain;
383 
384 	ibuf = &iev->ibuf;
385 
386 	if (event & EV_READ) {
387 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
388 			fatal("imsg_read error");
389 		if (n == 0)	/* Connection closed. */
390 			shut = 1;
391 	}
392 	if (event & EV_WRITE) {
393 		if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
394 			fatal("msgbuf_write");
395 		if (n == 0)	/* Connection closed. */
396 			shut = 1;
397 	}
398 
399 	for (;;) {
400 		if ((n = imsg_get(ibuf, &imsg)) == -1)
401 			fatal("imsg_get");
402 		if (n == 0)	/* No more messages. */
403 			break;
404 
405 		switch (imsg.hdr.type) {
406 		case IMSG_OPEN_ICMP6SOCK:
407 			log_debug("IMSG_OPEN_ICMP6SOCK");
408 			if (IMSG_DATA_SIZE(imsg) != sizeof(rdomain))
409 				fatalx("%s: IMSG_OPEN_ICMP6SOCK wrong length: "
410 				    "%lu", __func__, IMSG_DATA_SIZE(imsg));
411 			memcpy(&rdomain, imsg.data, sizeof(rdomain));
412 			open_icmp6sock(rdomain);
413 			break;
414 		case IMSG_CTL_RELOAD:
415 			if (main_reload() == -1)
416 				log_warnx("configuration reload failed");
417 			else
418 				log_warnx("configuration reloaded");
419 			break;
420 		case IMSG_CTL_LOG_VERBOSE:
421 			if (IMSG_DATA_SIZE(imsg) != sizeof(verbose))
422 				fatalx("%s: IMSG_CTL_LOG_VERBOSE wrong length: "
423 				    "%lu", __func__, IMSG_DATA_SIZE(imsg));
424 			memcpy(&verbose, imsg.data, sizeof(verbose));
425 			log_setverbose(verbose);
426 			break;
427 		default:
428 			log_debug("%s: error handling imsg %d", __func__,
429 			    imsg.hdr.type);
430 			break;
431 		}
432 		imsg_free(&imsg);
433 	}
434 	if (!shut)
435 		imsg_event_add(iev);
436 	else {
437 		/* This pipe is dead. Remove its event handler */
438 		event_del(&iev->ev);
439 		event_loopexit(NULL);
440 	}
441 }
442 
443 void
444 main_dispatch_engine(int fd, short event, void *bula)
445 {
446 	struct imsgev	*iev = bula;
447 	struct imsgbuf  *ibuf;
448 	struct imsg	 imsg;
449 	ssize_t		 n;
450 	int		 shut = 0;
451 
452 	ibuf = &iev->ibuf;
453 
454 	if (event & EV_READ) {
455 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
456 			fatal("imsg_read error");
457 		if (n == 0)	/* Connection closed. */
458 			shut = 1;
459 	}
460 	if (event & EV_WRITE) {
461 		if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
462 			fatal("msgbuf_write");
463 		if (n == 0)	/* Connection closed. */
464 			shut = 1;
465 	}
466 
467 	for (;;) {
468 		if ((n = imsg_get(ibuf, &imsg)) == -1)
469 			fatal("imsg_get");
470 		if (n == 0)	/* No more messages. */
471 			break;
472 
473 		switch (imsg.hdr.type) {
474 		default:
475 			log_debug("%s: error handling imsg %d", __func__,
476 			    imsg.hdr.type);
477 			break;
478 		}
479 		imsg_free(&imsg);
480 	}
481 	if (!shut)
482 		imsg_event_add(iev);
483 	else {
484 		/* This pipe is dead. Remove its event handler. */
485 		event_del(&iev->ev);
486 		event_loopexit(NULL);
487 	}
488 }
489 
490 int
491 main_imsg_compose_frontend(int type, int fd, void *data, uint16_t datalen)
492 {
493 	if (iev_frontend)
494 		return (imsg_compose_event(iev_frontend, type, 0, 0, fd, data,
495 		    datalen));
496 	else
497 		return (-1);
498 }
499 
500 void
501 main_imsg_compose_engine(int type, pid_t pid, void *data, uint16_t datalen)
502 {
503 	if (iev_engine)
504 		imsg_compose_event(iev_engine, type, 0, pid, -1, data,
505 		    datalen);
506 }
507 
508 void
509 imsg_event_add(struct imsgev *iev)
510 {
511 	iev->events = EV_READ;
512 	if (iev->ibuf.w.queued)
513 		iev->events |= EV_WRITE;
514 
515 	event_del(&iev->ev);
516 	event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev);
517 	event_add(&iev->ev, NULL);
518 }
519 
520 int
521 imsg_compose_event(struct imsgev *iev, uint16_t type, uint32_t peerid,
522     pid_t pid, int fd, void *data, uint16_t datalen)
523 {
524 	int	ret;
525 
526 	if ((ret = imsg_compose(&iev->ibuf, type, peerid, pid, fd, data,
527 	    datalen)) != -1)
528 		imsg_event_add(iev);
529 
530 	return (ret);
531 }
532 
533 static int
534 main_imsg_send_ipc_sockets(struct imsgbuf *frontend_buf,
535     struct imsgbuf *engine_buf)
536 {
537 	int pipe_frontend2engine[2];
538 
539 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
540 	    PF_UNSPEC, pipe_frontend2engine) == -1)
541 		return (-1);
542 
543 	if (imsg_compose(frontend_buf, IMSG_SOCKET_IPC, 0, 0,
544 	    pipe_frontend2engine[0], NULL, 0) == -1)
545 		return (-1);
546 	if (imsg_compose(engine_buf, IMSG_SOCKET_IPC, 0, 0,
547 	    pipe_frontend2engine[1], NULL, 0) == -1)
548 		return (-1);
549 
550 	return (0);
551 }
552 
553 int
554 main_reload(void)
555 {
556 	struct rad_conf *xconf;
557 
558 	if ((xconf = parse_config(conffile)) == NULL)
559 		return (-1);
560 
561 	if (main_imsg_send_config(xconf) == -1)
562 		return (-1);
563 
564 	merge_config(main_conf, xconf);
565 
566 	return (0);
567 }
568 
569 int
570 main_imsg_send_config(struct rad_conf *xconf)
571 {
572 	struct ra_iface_conf	*ra_iface_conf;
573 	struct ra_prefix_conf	*ra_prefix_conf;
574 	struct ra_rdnss_conf	*ra_rdnss_conf;
575 	struct ra_dnssl_conf	*ra_dnssl_conf;
576 
577 	/* Send fixed part of config to children. */
578 	if (main_sendboth(IMSG_RECONF_CONF, xconf, sizeof(*xconf)) == -1)
579 		return (-1);
580 
581 	/* send global dns options to children */
582 	SIMPLEQ_FOREACH(ra_rdnss_conf, &xconf->ra_options.ra_rdnss_list,
583 	    entry) {
584 		if (main_sendboth(IMSG_RECONF_RA_RDNSS, ra_rdnss_conf,
585 		    sizeof(*ra_rdnss_conf)) == -1)
586 			return (-1);
587 	}
588 	SIMPLEQ_FOREACH(ra_dnssl_conf, &xconf->ra_options.ra_dnssl_list,
589 	    entry) {
590 		if (main_sendboth(IMSG_RECONF_RA_DNSSL, ra_dnssl_conf,
591 		    sizeof(*ra_dnssl_conf)) == -1)
592 			return (-1);
593 	}
594 
595 	/* Send the interface list to children. */
596 	SIMPLEQ_FOREACH(ra_iface_conf, &xconf->ra_iface_list, entry) {
597 		if (main_sendboth(IMSG_RECONF_RA_IFACE, ra_iface_conf,
598 		    sizeof(*ra_iface_conf)) == -1)
599 			return (-1);
600 		if (ra_iface_conf->autoprefix) {
601 			if (main_sendboth(IMSG_RECONF_RA_AUTOPREFIX,
602 			    ra_iface_conf->autoprefix,
603 			    sizeof(*ra_iface_conf->autoprefix)) == -1)
604 				return (-1);
605 		}
606 		SIMPLEQ_FOREACH(ra_prefix_conf, &ra_iface_conf->ra_prefix_list,
607 		    entry) {
608 			if (main_sendboth(IMSG_RECONF_RA_PREFIX,
609 			    ra_prefix_conf, sizeof(*ra_prefix_conf)) == -1)
610 				return (-1);
611 		}
612 		SIMPLEQ_FOREACH(ra_rdnss_conf,
613 		    &ra_iface_conf->ra_options.ra_rdnss_list, entry) {
614 			if (main_sendboth(IMSG_RECONF_RA_RDNSS, ra_rdnss_conf,
615 			    sizeof(*ra_rdnss_conf)) == -1)
616 				return (-1);
617 		}
618 		SIMPLEQ_FOREACH(ra_dnssl_conf,
619 		    &ra_iface_conf->ra_options.ra_dnssl_list, entry) {
620 			if (main_sendboth(IMSG_RECONF_RA_DNSSL, ra_dnssl_conf,
621 			    sizeof(*ra_dnssl_conf)) == -1)
622 				return (-1);
623 		}
624 	}
625 
626 	/* Tell children the revised config is now complete. */
627 	if (main_sendboth(IMSG_RECONF_END, NULL, 0) == -1)
628 		return (-1);
629 
630 	return (0);
631 }
632 
633 int
634 main_sendboth(enum imsg_type type, void *buf, uint16_t len)
635 {
636 	if (imsg_compose_event(iev_frontend, type, 0, 0, -1, buf, len) == -1)
637 		return (-1);
638 	if (imsg_compose_event(iev_engine, type, 0, 0, -1, buf, len) == -1)
639 		return (-1);
640 	return (0);
641 }
642 
643 void
644 free_ra_iface_conf(struct ra_iface_conf *ra_iface_conf)
645 {
646 	struct ra_prefix_conf	*prefix;
647 
648 	if (!ra_iface_conf)
649 		return;
650 
651 	free(ra_iface_conf->autoprefix);
652 
653 	while ((prefix = SIMPLEQ_FIRST(&ra_iface_conf->ra_prefix_list)) !=
654 	    NULL) {
655 		SIMPLEQ_REMOVE_HEAD(&ra_iface_conf->ra_prefix_list, entry);
656 		free(prefix);
657 	}
658 
659 	free_dns_options(&ra_iface_conf->ra_options);
660 
661 	free(ra_iface_conf);
662 }
663 
664 void
665 free_dns_options(struct ra_options_conf *ra_options)
666 {
667 	struct ra_rdnss_conf	*ra_rdnss;
668 	struct ra_dnssl_conf	*ra_dnssl;
669 
670 	while ((ra_rdnss = SIMPLEQ_FIRST(&ra_options->ra_rdnss_list)) != NULL) {
671 		SIMPLEQ_REMOVE_HEAD(&ra_options->ra_rdnss_list, entry);
672 		free(ra_rdnss);
673 	}
674 	ra_options->rdnss_count = 0;
675 
676 	while ((ra_dnssl = SIMPLEQ_FIRST(&ra_options->ra_dnssl_list)) != NULL) {
677 		SIMPLEQ_REMOVE_HEAD(&ra_options->ra_dnssl_list, entry);
678 		free(ra_dnssl);
679 	}
680 	ra_options->dnssl_len = 0;
681 }
682 
683 void
684 merge_config(struct rad_conf *conf, struct rad_conf *xconf)
685 {
686 	struct ra_iface_conf	*ra_iface_conf;
687 
688 	/* Remove & discard existing interfaces. */
689 	while ((ra_iface_conf = SIMPLEQ_FIRST(&conf->ra_iface_list)) != NULL) {
690 		SIMPLEQ_REMOVE_HEAD(&conf->ra_iface_list, entry);
691 		free_ra_iface_conf(ra_iface_conf);
692 	}
693 	free_dns_options(&conf->ra_options);
694 
695 	conf->ra_options = xconf->ra_options;
696 	SIMPLEQ_INIT(&conf->ra_options.ra_rdnss_list);
697 	SIMPLEQ_INIT(&conf->ra_options.ra_dnssl_list);
698 
699 	/* Add new interfaces. */
700 	SIMPLEQ_CONCAT(&conf->ra_iface_list, &xconf->ra_iface_list);
701 
702 	/* Add dns options */
703 	SIMPLEQ_CONCAT(&conf->ra_options.ra_rdnss_list,
704 	    &xconf->ra_options.ra_rdnss_list);
705 	SIMPLEQ_CONCAT(&conf->ra_options.ra_dnssl_list,
706 	    &xconf->ra_options.ra_dnssl_list);
707 	free(xconf);
708 }
709 
710 struct rad_conf *
711 config_new_empty(void)
712 {
713 	struct rad_conf	*xconf;
714 
715 	xconf = calloc(1, sizeof(*xconf));
716 	if (xconf == NULL)
717 		fatal(NULL);
718 
719 	SIMPLEQ_INIT(&xconf->ra_iface_list);
720 
721 	xconf->ra_options.dfr = 1;
722 	xconf->ra_options.cur_hl = 0;
723 	xconf->ra_options.m_flag = 0;
724 	xconf->ra_options.o_flag = 0;
725 	xconf->ra_options.router_lifetime = ADV_DEFAULT_LIFETIME;
726 	xconf->ra_options.reachable_time = 0;
727 	xconf->ra_options.retrans_timer = 0;
728 	xconf->ra_options.mtu = 0;
729 	xconf->ra_options.rdns_lifetime = DEFAULT_RDNS_LIFETIME;
730 	SIMPLEQ_INIT(&xconf->ra_options.ra_rdnss_list);
731 	SIMPLEQ_INIT(&xconf->ra_options.ra_dnssl_list);
732 
733 	return (xconf);
734 }
735 
736 void
737 config_clear(struct rad_conf *conf)
738 {
739 	struct rad_conf	*xconf;
740 
741 	/* Merge current config with an empty config. */
742 	xconf = config_new_empty();
743 	merge_config(conf, xconf);
744 
745 	free(conf);
746 }
747 
748 void
749 mask_prefix(struct in6_addr* in6, int len)
750 {
751 	uint8_t	bitmask[8] = {0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe};
752 	int	i, skip;
753 
754 	if (len < 0 || len > 128)
755 		fatalx("invalid prefix length: %d", len);
756 
757 	skip = len / 8;
758 
759 	if (skip < 16)
760 		in6->s6_addr[skip] &= bitmask[len % 8];
761 
762 	for (i = skip + 1; i < 16; i++)
763 		in6->s6_addr[i] = 0;
764 }
765 
766 const char*
767 sin6_to_str(struct sockaddr_in6 *sin6)
768 {
769 	static char hbuf[NI_MAXHOST];
770 	int error;
771 
772 	error = getnameinfo((struct sockaddr *)sin6, sin6->sin6_len, hbuf,
773 	    sizeof(hbuf), NULL, 0, NI_NUMERICHOST | NI_NUMERICSERV);
774 	if (error) {
775 		log_warnx("%s", gai_strerror(error));
776 		strlcpy(hbuf, "unknown", sizeof(hbuf));
777 	}
778 	return hbuf;
779 }
780 
781 const char*
782 in6_to_str(struct in6_addr *in6)
783 {
784 
785 	struct sockaddr_in6	sin6;
786 
787 	memset(&sin6, 0, sizeof(sin6));
788 	sin6.sin6_len = sizeof(sin6);
789 	sin6.sin6_family = AF_INET6;
790 	sin6.sin6_addr = *in6;
791 
792 	return (sin6_to_str(&sin6));
793 }
794 
795 void
796 open_icmp6sock(int rdomain)
797 {
798 	int			 icmp6sock, on = 1, off = 0;
799 
800 	log_debug("%s: %d", __func__, rdomain);
801 
802 	if ((icmp6sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC,
803 	    IPPROTO_ICMPV6)) == -1)
804 		fatal("ICMPv6 socket");
805 
806 	if (setsockopt(icmp6sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on,
807 	    sizeof(on)) == -1)
808 		fatal("IPV6_RECVPKTINFO");
809 
810 	if (setsockopt(icmp6sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &on,
811 	    sizeof(on)) == -1)
812 		fatal("IPV6_RECVHOPLIMIT");
813 
814 	if (setsockopt(icmp6sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &off,
815 	    sizeof(off)) == -1)
816 		fatal("IPV6_RECVHOPLIMIT");
817 
818 	if (setsockopt(icmp6sock, SOL_SOCKET, SO_RTABLE, &rdomain,
819 	    sizeof(rdomain)) == -1) {
820 		/* we might race against removal of the rdomain */
821 		log_warn("setsockopt SO_RTABLE");
822 		close(icmp6sock);
823 		return;
824 	}
825 
826 	main_imsg_compose_frontend(IMSG_ICMP6SOCK, icmp6sock, &rdomain,
827 	    sizeof(rdomain));
828 }
829