interface.c revision 1.17 
1/*	$OpenBSD: interface.c,v 1.17 2013/06/04 02:25:28 claudio Exp $ */
2
3/*
4 * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
5 * Copyright (c) 2004, 2005, 2008 Esben Norby <norby@openbsd.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include <sys/types.h>
21#include <sys/ioctl.h>
22#include <sys/time.h>
23#include <sys/socket.h>
24#include <netinet/in.h>
25#include <arpa/inet.h>
26#include <net/if.h>
27#include <net/if_types.h>
28#include <fcntl.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 "ldpd.h"
38#include "ldp.h"
39#include "log.h"
40#include "ldpe.h"
41
42extern struct ldpd_conf        *leconf;
43
44int		 if_act_start(struct iface *);
45int		 if_act_reset(struct iface *);
46int		 if_act_update(struct iface *);
47void		 if_hello_timer(int, short, void *);
48void		 if_start_hello_timer(struct iface *);
49void		 if_stop_hello_timer(struct iface *);
50struct nbr	*if_elect(struct nbr *, struct nbr *);
51
52struct {
53	int			state;
54	enum iface_event	event;
55	enum iface_action	action;
56	int			new_state;
57} iface_fsm[] = {
58    /* current state	event that happened	action to take	resulting state */
59    {IF_STA_DOWN,	IF_EVT_DOWN,		IF_ACT_NOTHING,	0},
60    {IF_STA_DOWN,	IF_EVT_UP,		IF_ACT_UPDATE,	0},
61    {IF_STA_DOWN,	IF_EVT_NEWADDR,		IF_ACT_UPDATE,	0},
62    {IF_STA_DOWN,	IF_EVT_DELADDR,		IF_ACT_NOTHING,	0},
63    {IF_STA_ACTIVE,	IF_EVT_DOWN,		IF_ACT_RST,	IF_STA_DOWN},
64    {IF_STA_ACTIVE,	IF_EVT_NEWADDR,		IF_ACT_NOTHING,	0},
65    {IF_STA_ACTIVE,	IF_EVT_DELADDR,		IF_ACT_UPDATE,	0},
66    {-1,		IF_EVT_NOTHING,		IF_ACT_NOTHING,	0},
67};
68
69const char * const if_event_names[] = {
70	"NOTHING",
71	"UP",
72	"DOWN",
73	"NEWADDR",
74	"DELADDR"
75};
76
77const char * const if_action_names[] = {
78	"NOTHING",
79	"UPDATE",
80	"RESET"
81};
82
83int
84if_fsm(struct iface *iface, enum iface_event event)
85{
86	int	old_state;
87	int	new_state = 0;
88	int	i, ret = 0;
89
90	old_state = iface->state;
91
92	for (i = 0; iface_fsm[i].state != -1; i++)
93		if ((iface_fsm[i].state & old_state) &&
94		    (iface_fsm[i].event == event)) {
95			new_state = iface_fsm[i].new_state;
96			break;
97		}
98
99	if (iface_fsm[i].state == -1) {
100		/* event outside of the defined fsm, ignore it. */
101		log_debug("if_fsm: interface %s, "
102		    "event %s not expected in state %s", iface->name,
103		    if_event_names[event], if_state_name(old_state));
104		return (0);
105	}
106
107	switch (iface_fsm[i].action) {
108	case IF_ACT_UPDATE:
109		ret = if_act_update(iface);
110		break;
111	case IF_ACT_RST:
112		ret = if_act_reset(iface);
113		break;
114	case IF_ACT_NOTHING:
115		/* do nothing */
116		break;
117	}
118
119	if (ret) {
120		log_debug("if_fsm: error changing state for interface %s, "
121		    "event %s, state %s", iface->name, if_event_names[event],
122		    if_state_name(old_state));
123		return (-1);
124	}
125
126	if (new_state != 0)
127		iface->state = new_state;
128
129	log_debug("if_fsm: event %s resulted in action %s and changing "
130	    "state for interface %s from %s to %s",
131	    if_event_names[event], if_action_names[iface_fsm[i].action],
132	    iface->name, if_state_name(old_state), if_state_name(iface->state));
133
134	return (ret);
135}
136
137struct iface *
138if_new(struct kif *kif)
139{
140	struct iface		*iface;
141
142	if ((iface = calloc(1, sizeof(*iface))) == NULL)
143		err(1, "if_new: calloc");
144
145	iface->state = IF_STA_DOWN;
146
147	strlcpy(iface->name, kif->ifname, sizeof(iface->name));
148
149	/* get type */
150	if (kif->flags & IFF_POINTOPOINT)
151		iface->type = IF_TYPE_POINTOPOINT;
152	if (kif->flags & IFF_BROADCAST &&
153	    kif->flags & IFF_MULTICAST)
154		iface->type = IF_TYPE_BROADCAST;
155
156	/* get mtu, index and flags */
157	iface->mtu = kif->mtu;
158	iface->ifindex = kif->ifindex;
159	iface->flags = kif->flags;
160	iface->linkstate = kif->link_state;
161	iface->media_type = kif->media_type;
162	iface->baudrate = kif->baudrate;
163
164	return (iface);
165}
166
167void
168if_del(struct iface *iface)
169{
170	struct adj		*adj;
171	struct if_addr		*if_addr;
172
173	log_debug("if_del: interface %s", iface->name);
174
175	if_stop_hello_timer(iface);
176
177	while ((adj = LIST_FIRST(&iface->adj_list)) != NULL) {
178		LIST_REMOVE(adj, iface_entry);
179		adj_del(adj);
180	}
181	while ((if_addr = LIST_FIRST(&iface->addr_list)) != NULL)
182		LIST_REMOVE(if_addr, iface_entry);
183
184	free(iface);
185}
186
187void
188if_init(struct ldpd_conf *xconf, struct iface *iface)
189{
190	/* set event handlers for interface */
191	evtimer_set(&iface->hello_timer, if_hello_timer, iface);
192
193	iface->discovery_fd = xconf->ldp_discovery_socket;
194}
195
196struct iface *
197if_lookup(u_short ifindex)
198{
199	struct iface *iface;
200
201	LIST_FOREACH(iface, &leconf->iface_list, entry)
202		if (iface->ifindex == ifindex)
203			return (iface);
204
205	return (NULL);
206}
207
208/* timers */
209/* ARGSUSED */
210void
211if_hello_timer(int fd, short event, void *arg)
212{
213	struct iface *iface = arg;
214	struct timeval tv;
215
216	send_hello(HELLO_LINK, iface, NULL);
217
218	/* reschedule hello_timer */
219	timerclear(&tv);
220	tv.tv_sec = iface->hello_interval;
221	if (evtimer_add(&iface->hello_timer, &tv) == -1)
222		fatal("if_hello_timer");
223}
224
225void
226if_start_hello_timer(struct iface *iface)
227{
228	struct timeval tv;
229
230	timerclear(&tv);
231	tv.tv_sec = iface->hello_interval;
232	if (evtimer_add(&iface->hello_timer, &tv) == -1)
233		fatal("if_start_hello_timer");
234}
235
236void
237if_stop_hello_timer(struct iface *iface)
238{
239	if (evtimer_pending(&iface->hello_timer, NULL) &&
240	    evtimer_del(&iface->hello_timer) == -1)
241		fatal("if_stop_hello_timer");
242}
243
244/* actions */
245int
246if_act_start(struct iface *iface)
247{
248	struct in_addr		 addr;
249	struct timeval		 now;
250
251	gettimeofday(&now, NULL);
252	iface->uptime = now.tv_sec;
253
254	inet_aton(AllRouters, &addr);
255	if (if_join_group(iface, &addr))
256		return (-1);
257
258	/* hello timer needs to be started in any case */
259	if_start_hello_timer(iface);
260	return (0);
261}
262
263int
264if_act_reset(struct iface *iface)
265{
266	struct in_addr		 addr;
267
268	if_stop_hello_timer(iface);
269
270	/* try to cleanup */
271	inet_aton(AllRouters, &addr);
272	if_leave_group(iface, &addr);
273
274	return (0);
275}
276
277int
278if_act_update(struct iface *iface)
279{
280	int ret;
281
282	if (iface->state == IF_STA_DOWN) {
283		if (!((iface->flags & IFF_UP) &&
284		    LINK_STATE_IS_UP(iface->linkstate)))
285			return (0);
286
287		if (LIST_EMPTY(&iface->addr_list))
288			return (0);
289
290		iface->state = IF_STA_ACTIVE;
291		ret = if_act_start(iface);
292	} else {
293		if (!LIST_EMPTY(&iface->addr_list))
294			return (0);
295
296		iface->state = IF_STA_DOWN;
297		ret = if_act_reset(iface);
298	}
299
300	return (ret);
301}
302
303struct ctl_iface *
304if_to_ctl(struct iface *iface)
305{
306	static struct ctl_iface	 ictl;
307	struct timeval		 tv, now, res;
308
309	memcpy(ictl.name, iface->name, sizeof(ictl.name));
310	ictl.rtr_id.s_addr = ldpe_router_id();
311	ictl.ifindex = iface->ifindex;
312	ictl.state = iface->state;
313	ictl.mtu = iface->mtu;
314	ictl.baudrate = iface->baudrate;
315	ictl.holdtime = iface->hello_holdtime;
316	ictl.hello_interval = iface->hello_interval;
317	ictl.flags = iface->flags;
318	ictl.type = iface->type;
319	ictl.linkstate = iface->linkstate;
320	ictl.mediatype = iface->media_type;
321	ictl.priority = iface->priority;
322
323	gettimeofday(&now, NULL);
324	if (evtimer_pending(&iface->hello_timer, &tv)) {
325		timersub(&tv, &now, &res);
326		ictl.hello_timer = res.tv_sec;
327	} else
328		ictl.hello_timer = -1;
329
330	if (iface->state != IF_STA_DOWN &&
331	    iface->uptime != 0) {
332		ictl.uptime = now.tv_sec - iface->uptime;
333	} else
334		ictl.uptime = 0;
335
336	return (&ictl);
337}
338
339/* misc */
340int
341if_set_mcast_ttl(int fd, u_int8_t ttl)
342{
343	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL,
344	    (char *)&ttl, sizeof(ttl)) < 0) {
345		log_warn("if_set_mcast_ttl: error setting "
346		    "IP_MULTICAST_TTL to %d", ttl);
347		return (-1);
348	}
349
350	return (0);
351}
352
353int
354if_set_tos(int fd, int tos)
355{
356	if (setsockopt(fd, IPPROTO_IP, IP_TOS, (int *)&tos, sizeof(tos)) < 0) {
357		log_warn("if_set_tos: error setting IP_TOS to 0x%x", tos);
358		return (-1);
359	}
360
361	return (0);
362}
363
364int
365if_set_recvif(int fd, int enable)
366{
367	if (setsockopt(fd, IPPROTO_IP, IP_RECVIF, &enable,
368	    sizeof(enable)) < 0) {
369		log_warn("if_set_recvif: error setting IP_RECVIF");
370		return (-1);
371	}
372	return (0);
373}
374
375void
376if_set_recvbuf(int fd)
377{
378	int	bsize;
379
380	bsize = 65535;
381	while (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bsize,
382	    sizeof(bsize)) == -1)
383		bsize /= 2;
384}
385
386int
387if_set_reuse(int fd, int enable)
388{
389	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &enable,
390	    sizeof(int)) < 0) {
391		log_warn("if_set_reuse: error setting SO_REUSEADDR");
392		return (-1);
393	}
394
395	return (0);
396}
397
398/*
399 * only one JOIN or DROP per interface and address is allowed so we need
400 * to keep track of what is added and removed.
401 */
402struct if_group_count {
403	LIST_ENTRY(if_group_count)	entry;
404	struct in_addr			addr;
405	unsigned int			ifindex;
406	int				count;
407};
408
409LIST_HEAD(,if_group_count) ifglist = LIST_HEAD_INITIALIZER(ifglist);
410
411int
412if_join_group(struct iface *iface, struct in_addr *addr)
413{
414	struct ip_mreq		 mreq;
415	struct if_group_count	*ifg;
416	struct if_addr		*if_addr;
417
418	LIST_FOREACH(ifg, &ifglist, entry)
419		if (iface->ifindex == ifg->ifindex &&
420		    addr->s_addr == ifg->addr.s_addr)
421			break;
422	if (ifg == NULL) {
423		if ((ifg = calloc(1, sizeof(*ifg))) == NULL)
424			fatal("if_join_group");
425		ifg->addr.s_addr = addr->s_addr;
426		ifg->ifindex = iface->ifindex;
427		LIST_INSERT_HEAD(&ifglist, ifg, entry);
428	}
429
430	if (ifg->count++ != 0)
431		/* already joined */
432		return (0);
433
434	if_addr = LIST_FIRST(&iface->addr_list);
435	mreq.imr_multiaddr.s_addr = addr->s_addr;
436	mreq.imr_interface.s_addr = if_addr->addr.s_addr;
437
438	if (setsockopt(iface->discovery_fd, IPPROTO_IP,
439	    IP_ADD_MEMBERSHIP, (void *)&mreq, sizeof(mreq)) < 0) {
440		log_warn("if_join_group: error IP_ADD_MEMBERSHIP, "
441		    "interface %s address %s", iface->name,
442		    inet_ntoa(*addr));
443		LIST_REMOVE(ifg, entry);
444		free(ifg);
445		return (-1);
446	}
447	return (0);
448}
449
450int
451if_leave_group(struct iface *iface, struct in_addr *addr)
452{
453	struct ip_mreq		 mreq;
454	struct if_group_count	*ifg;
455	struct if_addr		*if_addr;
456
457	LIST_FOREACH(ifg, &ifglist, entry)
458		if (iface->ifindex == ifg->ifindex &&
459		    addr->s_addr == ifg->addr.s_addr)
460			break;
461
462	/* if interface is not found just try to drop membership */
463	if (ifg) {
464		if (--ifg->count != 0)
465			/* others still joined */
466			return (0);
467
468		LIST_REMOVE(ifg, entry);
469		free(ifg);
470	}
471
472	if_addr = LIST_FIRST(&iface->addr_list);
473	if (!if_addr)
474		return (0);
475
476	mreq.imr_multiaddr.s_addr = addr->s_addr;
477	mreq.imr_interface.s_addr = if_addr->addr.s_addr;
478
479	if (setsockopt(iface->discovery_fd, IPPROTO_IP,
480	    IP_DROP_MEMBERSHIP, (void *)&mreq, sizeof(mreq)) < 0) {
481		log_warn("if_leave_group: error IP_DROP_MEMBERSHIP, "
482		    "interface %s address %s", iface->name,
483		    inet_ntoa(*addr));
484		return (-1);
485	}
486
487	return (0);
488}
489
490int
491if_set_mcast(struct iface *iface)
492{
493	struct if_addr		*if_addr;
494
495	if_addr = LIST_FIRST(&iface->addr_list);
496
497	if (setsockopt(iface->discovery_fd, IPPROTO_IP, IP_MULTICAST_IF,
498	    &if_addr->addr.s_addr, sizeof(if_addr->addr.s_addr)) < 0) {
499		log_debug("if_set_mcast: error setting "
500		    "IP_MULTICAST_IF, interface %s", iface->name);
501		return (-1);
502	}
503
504	return (0);
505}
506
507int
508if_set_mcast_loop(int fd)
509{
510	u_int8_t	loop = 0;
511
512	if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
513	    (char *)&loop, sizeof(loop)) < 0) {
514		log_warn("if_set_mcast_loop: error setting IP_MULTICAST_LOOP");
515		return (-1);
516	}
517
518	return (0);
519}
520