xref: /openbsd-src/usr.sbin/ripd/interface.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: interface.c,v 1.6 2008/12/17 14:19:39 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 	/* XXX as in ospfd I would like to kill that. This is a design error */
76 	iface->fd = xconf->rip_socket;
77 
78 	ripe_demote_iface(iface, 0);
79 }
80 
81 int
82 if_fsm(struct iface *iface, enum iface_event event)
83 {
84 	int	 old_state;
85 	int	 new_state = 0;
86 	int	 i, ret = 0;
87 
88 	old_state = iface->state;
89 
90 	for (i = 0; iface_fsm[i].state != -1; i++)
91 		if ((iface_fsm[i].state & old_state) &&
92 		    (iface_fsm[i].event == event)) {
93 			new_state = iface_fsm[i].new_state;
94 			break;
95 		}
96 
97 	if (iface_fsm[i].state == -1) {
98 		/* event outside of the defined fsm, ignore it. */
99 		log_debug("if_fsm: interface %s, "
100 		    "event '%s' not expected in state '%s'", iface->name,
101 		    if_event_name(event), if_state_name(old_state));
102 		return (0);
103 	}
104 
105 	switch (iface_fsm[i].action) {
106 	case IF_ACT_STRT:
107 		ret = if_act_start(iface);
108 		break;
109 	case IF_ACT_RST:
110 		ret = if_act_reset(iface);
111 		break;
112 	case IF_ACT_NOTHING:
113 		/* do nothing */
114 		break;
115 	}
116 
117 	if (ret) {
118 		log_debug("if_fsm: error changing state for interface %s, "
119 		    "event '%s', state '%s'", iface->name, if_event_name(event),
120 		    if_state_name(old_state));
121 		return (0);
122 	}
123 
124 	if (new_state != 0)
125 		iface->state = new_state;
126 
127 	if (old_state == IF_STA_ACTIVE && iface->state == IF_STA_DOWN)
128 		ripe_demote_iface(iface, 0);
129 	if (old_state & IF_STA_DOWN && iface->state == IF_STA_ACTIVE)
130 		ripe_demote_iface(iface, 1);
131 
132 	log_debug("if_fsm: event '%s' resulted in action '%s' and changing "
133 	    "state for interface %s from '%s' to '%s'",
134 	    if_event_name(event), if_action_name(iface_fsm[i].action),
135 	    iface->name, if_state_name(old_state), if_state_name(iface->state));
136 
137 	return (ret);
138 }
139 
140 struct iface *
141 if_find_index(u_short ifindex)
142 {
143 	struct iface	 *iface;
144 
145 	LIST_FOREACH(iface, &conf->iface_list, entry) {
146 		if (iface->ifindex == ifindex)
147 			return (iface);
148 	}
149 
150 	return (NULL);
151 }
152 
153 
154 /* actions */
155 int
156 if_act_start(struct iface *iface)
157 {
158 	struct in_addr	 addr;
159 	struct timeval	 now;
160 
161 	if (iface->passive) {
162 		log_debug("if_act_start: cannot start passive interface %s",
163 		    iface->name);
164 		return (0);
165 	}
166 
167 	if (!((iface->flags & IFF_UP) &&
168 	    (LINK_STATE_IS_UP(iface->linkstate) ||
169 	    (iface->linkstate == LINK_STATE_UNKNOWN &&
170 	    iface->media_type != IFT_CARP)))) {
171 		log_debug("if_act_start: interface %s link down",
172 		    iface->name);
173 		return (0);
174 	}
175 
176 	gettimeofday(&now, NULL);
177 	iface->uptime = now.tv_sec;
178 
179 	switch (iface->type) {
180 	case IF_TYPE_POINTOPOINT:
181 	case IF_TYPE_BROADCAST:
182 		inet_aton(ALL_RIP_ROUTERS, &addr);
183 		if (if_join_group(iface, &addr)) {
184 			log_warn("if_act_start: error joining group %s, "
185 			    "interface %s", inet_ntoa(addr), iface->name);
186 			return (-1);
187 		}
188 
189 		iface->state = IF_STA_ACTIVE;
190 		break;
191 	default:
192 		fatalx("if_act_start: unknown interface type");
193 	}
194 
195 	return (0);
196 }
197 
198 int
199 if_act_reset(struct iface *iface)
200 {
201 	struct nbr		*nbr = NULL;
202 	struct in_addr		 addr;
203 
204 	if (iface->passive)
205 		return (0);
206 
207 	switch (iface->type) {
208 	case IF_TYPE_POINTOPOINT:
209 	case IF_TYPE_BROADCAST:
210 		inet_aton(ALL_RIP_ROUTERS, &addr);
211 		if (if_leave_group(iface, &addr)) {
212 		log_warn("if_act_reset: error leaving group %s, "
213 		    "interface %s", inet_ntoa(addr), iface->name);
214 		}
215 		break;
216 	default:
217 		fatalx("if_act_reset: unknown interface type");
218 	}
219 
220 	LIST_FOREACH(nbr, &iface->nbr_list, entry) {
221 		if (nbr_fsm(nbr, NBR_EVT_KILL_NBR)) {
222 			log_debug("if_act_reset: error killing neighbor %s",
223 			    inet_ntoa(nbr->id));
224 		}
225 	}
226 
227 	return (0);
228 }
229 
230 const char *
231 if_event_name(int event)
232 {
233 	return (if_event_names[event]);
234 }
235 
236 const char *
237 if_action_name(int action)
238 {
239 	return (if_action_names[action]);
240 }
241 
242 /* misc */
243 int
244 if_set_mcast_ttl(int fd, u_int8_t ttl)
245 {
246 	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL,
247 	    (char *)&ttl, sizeof(ttl)) < 0) {
248 		log_warn("if_set_mcast_ttl: error setting "
249 		    "IP_MULTICAST_TTL to %d", ttl);
250 		return (-1);
251 	}
252 
253 	return (0);
254 }
255 
256 int
257 if_set_opt(int fd)
258 {
259 	int	 yes = 1;
260 
261 	if (setsockopt(fd, IPPROTO_IP, IP_RECVIF, &yes,
262 	    sizeof(int)) < 0) {
263 		log_warn("if_set_opt: error setting IP_RECVIF");
264 		return (-1);
265 	}
266 
267 	return (0);
268 }
269 
270 int
271 if_set_tos(int fd, int tos)
272 {
273 	if (setsockopt(fd, IPPROTO_IP, IP_TOS,
274 	    (int *)&tos, sizeof(tos)) < 0) {
275 		log_warn("if_set_tos: error setting IP_TOS to 0x%x", tos);
276 		return (-1);
277 	}
278 
279 	return (0);
280 }
281 
282 int
283 if_set_mcast(struct iface *iface)
284 {
285 	switch (iface->type) {
286 	case IF_TYPE_POINTOPOINT:
287 	case IF_TYPE_BROADCAST:
288 		if (setsockopt(iface->fd, IPPROTO_IP, IP_MULTICAST_IF,
289 		    &iface->addr.s_addr, sizeof(iface->addr.s_addr)) < 0) {
290 			log_debug("if_set_mcast: error setting "
291 				"IP_MULTICAST_IF, interface %s", iface->name);
292 			return (-1);
293 		}
294 		break;
295 	default:
296 		fatalx("if_set_mcast: unknown interface type");
297 	}
298 
299 	return (0);
300 }
301 
302 int
303 if_set_mcast_loop(int fd)
304 {
305 	u_int8_t	 loop = 0;
306 
307 	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
308 	    (char *)&loop, sizeof(loop)) < 0) {
309 		log_warn("if_set_mcast_loop: error setting IP_MULTICAST_LOOP");
310 		return (-1);
311 	}
312 
313 	return (0);
314 }
315 
316 void
317 if_set_recvbuf(int fd)
318 {
319 	int	 bsize;
320 
321 	bsize = 65535;
322 	while (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bsize,
323 	    sizeof(bsize)) == -1)
324 		bsize /= 2;
325 }
326 
327 int
328 if_join_group(struct iface *iface, struct in_addr *addr)
329 {
330 	struct ip_mreq	 mreq;
331 
332 	switch (iface->type) {
333 	case IF_TYPE_POINTOPOINT:
334 	case IF_TYPE_BROADCAST:
335 		mreq.imr_multiaddr.s_addr = addr->s_addr;
336 		mreq.imr_interface.s_addr = iface->addr.s_addr;
337 
338 		if (setsockopt(iface->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
339 		    (void *)&mreq, sizeof(mreq)) < 0)
340 			return (-1);
341 		break;
342 	default:
343 		fatalx("if_join_group: unknown interface type");
344 	}
345 
346 	return (0);
347 }
348 
349 int
350 if_leave_group(struct iface *iface, struct in_addr *addr)
351 {
352 	struct ip_mreq	 mreq;
353 
354 	switch (iface->type) {
355 	case IF_TYPE_POINTOPOINT:
356 	case IF_TYPE_BROADCAST:
357 		mreq.imr_multiaddr.s_addr = addr->s_addr;
358 		mreq.imr_interface.s_addr = iface->addr.s_addr;
359 
360 		if (setsockopt(iface->fd, IPPROTO_IP, IP_DROP_MEMBERSHIP,
361 		    (void *)&mreq, sizeof(mreq)) < 0)
362 			return (-1);
363 		break;
364 	default:
365 		fatalx("if_leave_group: unknown interface type");
366 	}
367 
368 	return (0);
369 }
370 
371 struct iface *
372 if_new(struct kif *kif)
373 {
374 	struct sockaddr_in	*sain;
375 	struct iface		*iface;
376 	struct ifreq		*ifr;
377 	int			s;
378 
379 	if ((iface = calloc(1, sizeof(*iface))) == NULL)
380 		err(1, "if_new: calloc");
381 
382 	iface->state = IF_STA_DOWN;
383 
384 	LIST_INIT(&iface->nbr_list);
385 	TAILQ_INIT(&iface->rp_list);
386 	TAILQ_INIT(&iface->rq_list);
387 
388 	strlcpy(iface->name, kif->ifname, sizeof(iface->name));
389 
390 	if ((ifr = calloc(1, sizeof(*ifr))) == NULL)
391 		err(1, "if_new: calloc");
392 
393 	/* set up ifreq */
394 	strlcpy(ifr->ifr_name, kif->ifname, sizeof(ifr->ifr_name));
395 	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
396 		err(1, "if_new: socket");
397 
398 	/* get type */
399 	if (kif->flags & IFF_POINTOPOINT)
400 		iface->type = IF_TYPE_POINTOPOINT;
401 	if (kif->flags & IFF_BROADCAST &&
402 	    kif->flags & IFF_MULTICAST)
403 		iface->type = IF_TYPE_BROADCAST;
404 	if (kif->flags & IFF_LOOPBACK) {
405 		iface->type = IF_TYPE_POINTOPOINT;
406 		/* XXX protect loopback from sending packets over lo? */
407 	}
408 
409 	/* get mtu, index and flags */
410 	iface->mtu = kif->mtu;
411 	iface->ifindex = kif->ifindex;
412 	iface->flags = kif->flags;
413 	iface->linkstate = kif->link_state;
414 	iface->media_type = kif->media_type;
415 	iface->baudrate = kif->baudrate;
416 
417 	/* get address */
418 	if (ioctl(s, SIOCGIFADDR, ifr) < 0)
419 		err(1, "if_new: cannot get address");
420 	sain = (struct sockaddr_in *)&ifr->ifr_addr;
421 	iface->addr = sain->sin_addr;
422 
423 	/* get mask */
424 	if (ioctl(s, SIOCGIFNETMASK, ifr) < 0)
425 		err(1, "if_new: cannot get mask");
426 	sain = (struct sockaddr_in *)&ifr->ifr_addr;
427 	iface->mask = sain->sin_addr;
428 
429 	/* get p2p dst address */
430 	if (kif->flags & IFF_POINTOPOINT) {
431 		if (ioctl(s, SIOCGIFDSTADDR, ifr) < 0)
432 			err(1, "if_new: cannot get dst addr");
433 		sain = (struct sockaddr_in *)&ifr->ifr_addr;
434 		iface->dst = sain->sin_addr;
435 	}
436 
437 	free(ifr);
438 	close(s);
439 
440 	return (iface);
441 }
442 
443 void
444 if_del(struct iface *iface)
445 {
446 	struct nbr	*nbr;
447 
448 	log_debug("if_del: interface %s", iface->name);
449 
450 	/* revert the demotion when the interface is deleted */
451 	if (iface->state == IF_STA_DOWN)
452                 ripe_demote_iface(iface, 1);
453 
454 	/* clear lists etc */
455 	while ((nbr = LIST_FIRST(&iface->nbr_list)) != NULL)
456 		nbr_act_del(nbr);
457 
458 	/* XXX rq_list, rp_list */
459 
460 	free(iface);
461 }
462 
463 struct ctl_iface *
464 if_to_ctl(struct iface *iface)
465 {
466 	static struct ctl_iface	 ictl;
467 	struct timeval		 now;
468 
469 	memcpy(ictl.name, iface->name, sizeof(ictl.name));
470 	memcpy(&ictl.addr, &iface->addr, sizeof(ictl.addr));
471 	memcpy(&ictl.mask, &iface->mask, sizeof(ictl.mask));
472 
473 	ictl.ifindex = iface->ifindex;
474 	ictl.state = iface->state;
475 	ictl.mtu = iface->mtu;
476 
477 	ictl.baudrate = iface->baudrate;
478 	ictl.flags = iface->flags;
479 	ictl.metric = iface->cost;
480 	ictl.type = iface->type;
481 	ictl.linkstate = iface->linkstate;
482 	ictl.passive = iface->passive;
483 	ictl.mediatype = iface->media_type;
484 
485 	gettimeofday(&now, NULL);
486 
487 	if (iface->state != IF_STA_DOWN) {
488 		ictl.uptime = now.tv_sec - iface->uptime;
489 	} else
490 		ictl.uptime = 0;
491 
492 	return (&ictl);
493 }
494