xref: /openbsd-src/usr.sbin/ripd/interface.c (revision 43003dfe3ad45d1698bed8a37f2b0f5b14f20d4f)
1 /*	$OpenBSD: interface.c,v 1.8 2009/09/26 18:24:58 michele Exp $ */
2 
3 /*
4  * Copyright (c) 2006 Michele Marchetto <mydecay@openbeer.it>
5  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
6  * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 #include <sys/types.h>
22 #include <sys/ioctl.h>
23 #include <sys/time.h>
24 #include <sys/socket.h>
25 #include <netinet/in.h>
26 #include <arpa/inet.h>
27 #include <net/if.h>
28 #include <net/if_types.h>
29 #include <ctype.h>
30 #include <err.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <string.h>
35 #include <event.h>
36 
37 #include "ripd.h"
38 #include "log.h"
39 #include "rip.h"
40 #include "rde.h"
41 #include "ripe.h"
42 
43 extern struct ripd_conf	*conf;
44 
45 int	 if_act_start(struct iface *);
46 int	 if_act_reset(struct iface *);
47 
48 struct {
49 	int			state;
50 	enum iface_event	event;
51 	enum iface_action	action;
52 	int			new_state;
53 } iface_fsm[] = {
54     /* current state	event that happened	action to take	resulting state */
55     {IF_STA_DOWN,	IF_EVT_UP,		IF_ACT_STRT,	0},
56     {IF_STA_ANY,	IF_EVT_DOWN,		IF_ACT_RST,	IF_STA_DOWN},
57     {-1,		IF_EVT_NOTHING,		IF_ACT_NOTHING,	0},
58 };
59 
60 const char * const if_action_names[] = {
61 	"NOTHING",
62 	"START",
63 	"RESET"
64 };
65 
66 static const char * const if_event_names[] = {
67 	"NOTHING",
68 	"UP",
69 	"DOWN",
70 };
71 
72 void
73 if_init(struct ripd_conf *xconf, struct iface *iface)
74 {
75 	struct ifreq	ifr;
76 	u_int		rdomain;
77 
78 	/* XXX as in ospfd I would like to kill that. This is a design error */
79 	iface->fd = xconf->rip_socket;
80 
81 	strlcpy(ifr.ifr_name, iface->name, sizeof(ifr.ifr_name));
82 	if (ioctl(iface->fd, SIOCGIFRTABLEID, (caddr_t)&ifr) == -1)
83 		rdomain = 0;
84 	else {
85 		rdomain = ifr.ifr_rdomainid;
86 		if (setsockopt(iface->fd, IPPROTO_IP, SO_RDOMAIN, &rdomain,
87 		    sizeof(rdomain)) == -1)
88 			fatal("failed to set rdomain");
89 	}
90 	if (rdomain != xconf->rdomain)
91 		fatalx("interface rdomain mismatch");
92 
93 	ripe_demote_iface(iface, 0);
94 }
95 
96 int
97 if_fsm(struct iface *iface, enum iface_event event)
98 {
99 	int	 old_state;
100 	int	 new_state = 0;
101 	int	 i, ret = 0;
102 
103 	old_state = iface->state;
104 
105 	for (i = 0; iface_fsm[i].state != -1; i++)
106 		if ((iface_fsm[i].state & old_state) &&
107 		    (iface_fsm[i].event == event)) {
108 			new_state = iface_fsm[i].new_state;
109 			break;
110 		}
111 
112 	if (iface_fsm[i].state == -1) {
113 		/* event outside of the defined fsm, ignore it. */
114 		log_debug("if_fsm: interface %s, "
115 		    "event '%s' not expected in state '%s'", iface->name,
116 		    if_event_name(event), if_state_name(old_state));
117 		return (0);
118 	}
119 
120 	switch (iface_fsm[i].action) {
121 	case IF_ACT_STRT:
122 		ret = if_act_start(iface);
123 		break;
124 	case IF_ACT_RST:
125 		ret = if_act_reset(iface);
126 		break;
127 	case IF_ACT_NOTHING:
128 		/* do nothing */
129 		break;
130 	}
131 
132 	if (ret) {
133 		log_debug("if_fsm: error changing state for interface %s, "
134 		    "event '%s', state '%s'", iface->name, if_event_name(event),
135 		    if_state_name(old_state));
136 		return (0);
137 	}
138 
139 	if (new_state != 0)
140 		iface->state = new_state;
141 
142 	if (old_state == IF_STA_ACTIVE && iface->state == IF_STA_DOWN)
143 		ripe_demote_iface(iface, 0);
144 	if (old_state & IF_STA_DOWN && iface->state == IF_STA_ACTIVE)
145 		ripe_demote_iface(iface, 1);
146 
147 	log_debug("if_fsm: event '%s' resulted in action '%s' and changing "
148 	    "state for interface %s from '%s' to '%s'",
149 	    if_event_name(event), if_action_name(iface_fsm[i].action),
150 	    iface->name, if_state_name(old_state), if_state_name(iface->state));
151 
152 	return (ret);
153 }
154 
155 struct iface *
156 if_find_index(u_short ifindex)
157 {
158 	struct iface	 *iface;
159 
160 	LIST_FOREACH(iface, &conf->iface_list, entry) {
161 		if (iface->ifindex == ifindex)
162 			return (iface);
163 	}
164 
165 	return (NULL);
166 }
167 
168 
169 /* actions */
170 int
171 if_act_start(struct iface *iface)
172 {
173 	struct in_addr	 addr;
174 	struct timeval	 now;
175 
176 	if (iface->passive) {
177 		log_debug("if_act_start: cannot start passive interface %s",
178 		    iface->name);
179 		return (0);
180 	}
181 
182 	if (!((iface->flags & IFF_UP) &&
183 	    (LINK_STATE_IS_UP(iface->linkstate) ||
184 	    (iface->linkstate == LINK_STATE_UNKNOWN &&
185 	    iface->media_type != IFT_CARP)))) {
186 		log_debug("if_act_start: interface %s link down",
187 		    iface->name);
188 		return (0);
189 	}
190 
191 	gettimeofday(&now, NULL);
192 	iface->uptime = now.tv_sec;
193 
194 	switch (iface->type) {
195 	case IF_TYPE_POINTOPOINT:
196 	case IF_TYPE_BROADCAST:
197 		inet_aton(ALL_RIP_ROUTERS, &addr);
198 		if (if_join_group(iface, &addr)) {
199 			log_warn("if_act_start: error joining group %s, "
200 			    "interface %s", inet_ntoa(addr), iface->name);
201 			return (-1);
202 		}
203 
204 		iface->state = IF_STA_ACTIVE;
205 		break;
206 	default:
207 		fatalx("if_act_start: unknown interface type");
208 	}
209 
210 	return (0);
211 }
212 
213 int
214 if_act_reset(struct iface *iface)
215 {
216 	struct nbr		*nbr = NULL;
217 	struct in_addr		 addr;
218 
219 	if (iface->passive)
220 		return (0);
221 
222 	switch (iface->type) {
223 	case IF_TYPE_POINTOPOINT:
224 	case IF_TYPE_BROADCAST:
225 		inet_aton(ALL_RIP_ROUTERS, &addr);
226 		if (if_leave_group(iface, &addr)) {
227 		log_warn("if_act_reset: error leaving group %s, "
228 		    "interface %s", inet_ntoa(addr), iface->name);
229 		}
230 		break;
231 	default:
232 		fatalx("if_act_reset: unknown interface type");
233 	}
234 
235 	LIST_FOREACH(nbr, &iface->nbr_list, entry) {
236 		if (nbr_fsm(nbr, NBR_EVT_KILL_NBR)) {
237 			log_debug("if_act_reset: error killing neighbor %s",
238 			    inet_ntoa(nbr->id));
239 		}
240 	}
241 
242 	return (0);
243 }
244 
245 const char *
246 if_event_name(int event)
247 {
248 	return (if_event_names[event]);
249 }
250 
251 const char *
252 if_action_name(int action)
253 {
254 	return (if_action_names[action]);
255 }
256 
257 /* misc */
258 int
259 if_set_mcast_ttl(int fd, u_int8_t ttl)
260 {
261 	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL,
262 	    (char *)&ttl, sizeof(ttl)) < 0) {
263 		log_warn("if_set_mcast_ttl: error setting "
264 		    "IP_MULTICAST_TTL to %d", ttl);
265 		return (-1);
266 	}
267 
268 	return (0);
269 }
270 
271 int
272 if_set_opt(int fd)
273 {
274 	int	 yes = 1;
275 
276 	if (setsockopt(fd, IPPROTO_IP, IP_RECVIF, &yes,
277 	    sizeof(int)) < 0) {
278 		log_warn("if_set_opt: error setting IP_RECVIF");
279 		return (-1);
280 	}
281 
282 	return (0);
283 }
284 
285 int
286 if_set_tos(int fd, int tos)
287 {
288 	if (setsockopt(fd, IPPROTO_IP, IP_TOS,
289 	    (int *)&tos, sizeof(tos)) < 0) {
290 		log_warn("if_set_tos: error setting IP_TOS to 0x%x", tos);
291 		return (-1);
292 	}
293 
294 	return (0);
295 }
296 
297 int
298 if_set_mcast(struct iface *iface)
299 {
300 	switch (iface->type) {
301 	case IF_TYPE_POINTOPOINT:
302 	case IF_TYPE_BROADCAST:
303 		if (setsockopt(iface->fd, IPPROTO_IP, IP_MULTICAST_IF,
304 		    &iface->addr.s_addr, sizeof(iface->addr.s_addr)) < 0) {
305 			log_debug("if_set_mcast: error setting "
306 				"IP_MULTICAST_IF, interface %s", iface->name);
307 			return (-1);
308 		}
309 		break;
310 	default:
311 		fatalx("if_set_mcast: unknown interface type");
312 	}
313 
314 	return (0);
315 }
316 
317 int
318 if_set_mcast_loop(int fd)
319 {
320 	u_int8_t	 loop = 0;
321 
322 	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
323 	    (char *)&loop, sizeof(loop)) < 0) {
324 		log_warn("if_set_mcast_loop: error setting IP_MULTICAST_LOOP");
325 		return (-1);
326 	}
327 
328 	return (0);
329 }
330 
331 void
332 if_set_recvbuf(int fd)
333 {
334 	int	 bsize;
335 
336 	bsize = 65535;
337 	while (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bsize,
338 	    sizeof(bsize)) == -1)
339 		bsize /= 2;
340 }
341 
342 int
343 if_join_group(struct iface *iface, struct in_addr *addr)
344 {
345 	struct ip_mreq	 mreq;
346 
347 	switch (iface->type) {
348 	case IF_TYPE_POINTOPOINT:
349 	case IF_TYPE_BROADCAST:
350 		mreq.imr_multiaddr.s_addr = addr->s_addr;
351 		mreq.imr_interface.s_addr = iface->addr.s_addr;
352 
353 		if (setsockopt(iface->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
354 		    (void *)&mreq, sizeof(mreq)) < 0)
355 			return (-1);
356 		break;
357 	default:
358 		fatalx("if_join_group: unknown interface type");
359 	}
360 
361 	return (0);
362 }
363 
364 int
365 if_leave_group(struct iface *iface, struct in_addr *addr)
366 {
367 	struct ip_mreq	 mreq;
368 
369 	switch (iface->type) {
370 	case IF_TYPE_POINTOPOINT:
371 	case IF_TYPE_BROADCAST:
372 		mreq.imr_multiaddr.s_addr = addr->s_addr;
373 		mreq.imr_interface.s_addr = iface->addr.s_addr;
374 
375 		if (setsockopt(iface->fd, IPPROTO_IP, IP_DROP_MEMBERSHIP,
376 		    (void *)&mreq, sizeof(mreq)) < 0)
377 			return (-1);
378 		break;
379 	default:
380 		fatalx("if_leave_group: unknown interface type");
381 	}
382 
383 	return (0);
384 }
385 
386 struct iface *
387 if_new(struct kif *kif)
388 {
389 	struct sockaddr_in	*sain;
390 	struct iface		*iface;
391 	struct ifreq		*ifr;
392 	int			s;
393 
394 	if ((iface = calloc(1, sizeof(*iface))) == NULL)
395 		err(1, "if_new: calloc");
396 
397 	iface->state = IF_STA_DOWN;
398 
399 	LIST_INIT(&iface->nbr_list);
400 	TAILQ_INIT(&iface->rp_list);
401 	TAILQ_INIT(&iface->rq_list);
402 
403 	strlcpy(iface->name, kif->ifname, sizeof(iface->name));
404 
405 	if ((ifr = calloc(1, sizeof(*ifr))) == NULL)
406 		err(1, "if_new: calloc");
407 
408 	/* set up ifreq */
409 	strlcpy(ifr->ifr_name, kif->ifname, sizeof(ifr->ifr_name));
410 	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
411 		err(1, "if_new: socket");
412 
413 	/* get type */
414 	if (kif->flags & IFF_POINTOPOINT)
415 		iface->type = IF_TYPE_POINTOPOINT;
416 	if (kif->flags & IFF_BROADCAST &&
417 	    kif->flags & IFF_MULTICAST)
418 		iface->type = IF_TYPE_BROADCAST;
419 	if (kif->flags & IFF_LOOPBACK) {
420 		iface->type = IF_TYPE_POINTOPOINT;
421 		/* XXX protect loopback from sending packets over lo? */
422 	}
423 
424 	/* get mtu, index and flags */
425 	iface->mtu = kif->mtu;
426 	iface->ifindex = kif->ifindex;
427 	iface->flags = kif->flags;
428 	iface->linkstate = kif->link_state;
429 	iface->media_type = kif->media_type;
430 	iface->baudrate = kif->baudrate;
431 
432 	/* get address */
433 	if (ioctl(s, SIOCGIFADDR, ifr) < 0)
434 		err(1, "if_new: cannot get address");
435 	sain = (struct sockaddr_in *)&ifr->ifr_addr;
436 	iface->addr = sain->sin_addr;
437 
438 	/* get mask */
439 	if (ioctl(s, SIOCGIFNETMASK, ifr) < 0)
440 		err(1, "if_new: cannot get mask");
441 	sain = (struct sockaddr_in *)&ifr->ifr_addr;
442 	iface->mask = sain->sin_addr;
443 
444 	/* get p2p dst address */
445 	if (kif->flags & IFF_POINTOPOINT) {
446 		if (ioctl(s, SIOCGIFDSTADDR, ifr) < 0)
447 			err(1, "if_new: cannot get dst addr");
448 		sain = (struct sockaddr_in *)&ifr->ifr_addr;
449 		iface->dst = sain->sin_addr;
450 	}
451 
452 	free(ifr);
453 	close(s);
454 
455 	return (iface);
456 }
457 
458 void
459 if_del(struct iface *iface)
460 {
461 	struct nbr	*nbr;
462 
463 	log_debug("if_del: interface %s", iface->name);
464 
465 	/* revert the demotion when the interface is deleted */
466 	if (iface->state == IF_STA_DOWN)
467 		ripe_demote_iface(iface, 1);
468 
469 	/* clear lists etc */
470 	while ((nbr = LIST_FIRST(&iface->nbr_list)) != NULL)
471 		nbr_act_del(nbr);
472 
473 	/* XXX rq_list, rp_list */
474 
475 	free(iface);
476 }
477 
478 struct ctl_iface *
479 if_to_ctl(struct iface *iface)
480 {
481 	static struct ctl_iface	 ictl;
482 	struct timeval		 now;
483 
484 	memcpy(ictl.name, iface->name, sizeof(ictl.name));
485 	memcpy(&ictl.addr, &iface->addr, sizeof(ictl.addr));
486 	memcpy(&ictl.mask, &iface->mask, sizeof(ictl.mask));
487 
488 	ictl.ifindex = iface->ifindex;
489 	ictl.state = iface->state;
490 	ictl.mtu = iface->mtu;
491 
492 	ictl.baudrate = iface->baudrate;
493 	ictl.flags = iface->flags;
494 	ictl.metric = iface->cost;
495 	ictl.type = iface->type;
496 	ictl.linkstate = iface->linkstate;
497 	ictl.passive = iface->passive;
498 	ictl.mediatype = iface->media_type;
499 
500 	gettimeofday(&now, NULL);
501 
502 	if (iface->state != IF_STA_DOWN) {
503 		ictl.uptime = now.tv_sec - iface->uptime;
504 	} else
505 		ictl.uptime = 0;
506 
507 	return (&ictl);
508 }
509