1 /* $OpenBSD: interface.c,v 1.16 2021/01/19 10:09:59 claudio 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
if_init(struct ripd_conf * xconf,struct iface * iface)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, SIOCGIFRDOMAIN, (caddr_t)&ifr) == -1)
83 rdomain = 0;
84 else {
85 rdomain = ifr.ifr_rdomainid;
86 if (setsockopt(iface->fd, SOL_SOCKET, SO_RTABLE, &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
if_fsm(struct iface * iface,enum iface_event event)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 *
if_find_index(u_short ifindex)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
if_act_start(struct iface * iface)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 log_debug("if_act_start: interface %s link down",
185 iface->name);
186 return (0);
187 }
188
189 gettimeofday(&now, NULL);
190 iface->uptime = now.tv_sec;
191
192 switch (iface->type) {
193 case IF_TYPE_POINTOPOINT:
194 case IF_TYPE_BROADCAST:
195 inet_aton(ALL_RIP_ROUTERS, &addr);
196 if (if_join_group(iface, &addr)) {
197 log_warn("if_act_start: error joining group %s, "
198 "interface %s", inet_ntoa(addr), iface->name);
199 return (-1);
200 }
201
202 iface->state = IF_STA_ACTIVE;
203 break;
204 default:
205 fatalx("if_act_start: unknown interface type");
206 }
207
208 return (0);
209 }
210
211 int
if_act_reset(struct iface * iface)212 if_act_reset(struct iface *iface)
213 {
214 struct nbr *nbr = NULL;
215 struct in_addr addr;
216
217 if (iface->passive)
218 return (0);
219
220 switch (iface->type) {
221 case IF_TYPE_POINTOPOINT:
222 case IF_TYPE_BROADCAST:
223 inet_aton(ALL_RIP_ROUTERS, &addr);
224 if (if_leave_group(iface, &addr)) {
225 log_warn("if_act_reset: error leaving group %s, "
226 "interface %s", inet_ntoa(addr), iface->name);
227 }
228 break;
229 default:
230 fatalx("if_act_reset: unknown interface type");
231 }
232
233 LIST_FOREACH(nbr, &iface->nbr_list, entry) {
234 if (nbr_fsm(nbr, NBR_EVT_KILL_NBR)) {
235 log_debug("if_act_reset: error killing neighbor %s",
236 inet_ntoa(nbr->id));
237 }
238 }
239
240 return (0);
241 }
242
243 const char *
if_event_name(int event)244 if_event_name(int event)
245 {
246 return (if_event_names[event]);
247 }
248
249 const char *
if_action_name(int action)250 if_action_name(int action)
251 {
252 return (if_action_names[action]);
253 }
254
255 /* misc */
256 int
if_set_mcast_ttl(int fd,u_int8_t ttl)257 if_set_mcast_ttl(int fd, u_int8_t ttl)
258 {
259 if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL,
260 (char *)&ttl, sizeof(ttl)) == -1) {
261 log_warn("if_set_mcast_ttl: error setting "
262 "IP_MULTICAST_TTL to %d", ttl);
263 return (-1);
264 }
265
266 return (0);
267 }
268
269 int
if_set_opt(int fd)270 if_set_opt(int fd)
271 {
272 int yes = 1;
273
274 if (setsockopt(fd, IPPROTO_IP, IP_RECVIF, &yes,
275 sizeof(int)) == -1) {
276 log_warn("if_set_opt: error setting IP_RECVIF");
277 return (-1);
278 }
279
280 return (0);
281 }
282
283 int
if_set_tos(int fd,int tos)284 if_set_tos(int fd, int tos)
285 {
286 if (setsockopt(fd, IPPROTO_IP, IP_TOS,
287 (int *)&tos, sizeof(tos)) == -1) {
288 log_warn("if_set_tos: error setting IP_TOS to 0x%x", tos);
289 return (-1);
290 }
291
292 return (0);
293 }
294
295 int
if_set_mcast(struct iface * iface)296 if_set_mcast(struct iface *iface)
297 {
298 switch (iface->type) {
299 case IF_TYPE_POINTOPOINT:
300 case IF_TYPE_BROADCAST:
301 if (setsockopt(iface->fd, IPPROTO_IP, IP_MULTICAST_IF,
302 &iface->addr.s_addr, sizeof(iface->addr.s_addr)) == -1) {
303 log_debug("if_set_mcast: error setting "
304 "IP_MULTICAST_IF, interface %s", iface->name);
305 return (-1);
306 }
307 break;
308 default:
309 fatalx("if_set_mcast: unknown interface type");
310 }
311
312 return (0);
313 }
314
315 int
if_set_mcast_loop(int fd)316 if_set_mcast_loop(int fd)
317 {
318 u_int8_t loop = 0;
319
320 if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
321 (char *)&loop, sizeof(loop)) == -1) {
322 log_warn("if_set_mcast_loop: error setting IP_MULTICAST_LOOP");
323 return (-1);
324 }
325
326 return (0);
327 }
328
329 void
if_set_recvbuf(int fd)330 if_set_recvbuf(int fd)
331 {
332 int bsize;
333
334 bsize = 65535;
335 while (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &bsize,
336 sizeof(bsize)) == -1)
337 bsize /= 2;
338 }
339
340 int
if_join_group(struct iface * iface,struct in_addr * addr)341 if_join_group(struct iface *iface, struct in_addr *addr)
342 {
343 struct ip_mreq mreq;
344
345 switch (iface->type) {
346 case IF_TYPE_POINTOPOINT:
347 case IF_TYPE_BROADCAST:
348 mreq.imr_multiaddr.s_addr = addr->s_addr;
349 mreq.imr_interface.s_addr = iface->addr.s_addr;
350
351 if (setsockopt(iface->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
352 (void *)&mreq, sizeof(mreq)) == -1)
353 return (-1);
354 break;
355 default:
356 fatalx("if_join_group: unknown interface type");
357 }
358
359 return (0);
360 }
361
362 int
if_leave_group(struct iface * iface,struct in_addr * addr)363 if_leave_group(struct iface *iface, struct in_addr *addr)
364 {
365 struct ip_mreq mreq;
366
367 switch (iface->type) {
368 case IF_TYPE_POINTOPOINT:
369 case IF_TYPE_BROADCAST:
370 mreq.imr_multiaddr.s_addr = addr->s_addr;
371 mreq.imr_interface.s_addr = iface->addr.s_addr;
372
373 if (setsockopt(iface->fd, IPPROTO_IP, IP_DROP_MEMBERSHIP,
374 (void *)&mreq, sizeof(mreq)) == -1)
375 return (-1);
376 break;
377 default:
378 fatalx("if_leave_group: unknown interface type");
379 }
380
381 return (0);
382 }
383
384 struct iface *
if_new(struct kif * kif)385 if_new(struct kif *kif)
386 {
387 struct sockaddr_in *sain;
388 struct iface *iface;
389 struct ifreq *ifr;
390 int s;
391
392 if ((iface = calloc(1, sizeof(*iface))) == NULL)
393 err(1, "if_new: calloc");
394
395 iface->state = IF_STA_DOWN;
396
397 LIST_INIT(&iface->nbr_list);
398 TAILQ_INIT(&iface->rp_list);
399 TAILQ_INIT(&iface->rq_list);
400
401 strlcpy(iface->name, kif->ifname, sizeof(iface->name));
402
403 if ((ifr = calloc(1, sizeof(*ifr))) == NULL)
404 err(1, "if_new: calloc");
405
406 /* set up ifreq */
407 strlcpy(ifr->ifr_name, kif->ifname, sizeof(ifr->ifr_name));
408 if ((s = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
409 0)) == -1)
410 err(1, "if_new: socket");
411
412 /* get type */
413 if (kif->flags & IFF_POINTOPOINT)
414 iface->type = IF_TYPE_POINTOPOINT;
415 if (kif->flags & IFF_BROADCAST &&
416 kif->flags & IFF_MULTICAST)
417 iface->type = IF_TYPE_BROADCAST;
418 if (kif->flags & IFF_LOOPBACK) {
419 iface->type = IF_TYPE_POINTOPOINT;
420 /* XXX protect loopback from sending packets over lo? */
421 }
422
423 /* get mtu, index and flags */
424 iface->mtu = kif->mtu;
425 iface->ifindex = kif->ifindex;
426 iface->flags = kif->flags;
427 iface->linkstate = kif->link_state;
428 iface->if_type = kif->if_type;
429 iface->baudrate = kif->baudrate;
430
431 /* get address */
432 if (ioctl(s, SIOCGIFADDR, ifr) == -1)
433 err(1, "if_new: cannot get address");
434 sain = (struct sockaddr_in *)&ifr->ifr_addr;
435 iface->addr = sain->sin_addr;
436
437 /* get mask */
438 if (ioctl(s, SIOCGIFNETMASK, ifr) == -1)
439 err(1, "if_new: cannot get mask");
440 sain = (struct sockaddr_in *)&ifr->ifr_addr;
441 iface->mask = sain->sin_addr;
442
443 /* get p2p dst address */
444 if (kif->flags & IFF_POINTOPOINT) {
445 if (ioctl(s, SIOCGIFDSTADDR, ifr) == -1)
446 err(1, "if_new: cannot get dst addr");
447 sain = (struct sockaddr_in *)&ifr->ifr_addr;
448 iface->dst = sain->sin_addr;
449 }
450
451 free(ifr);
452 close(s);
453
454 return (iface);
455 }
456
457 void
if_del(struct iface * iface)458 if_del(struct iface *iface)
459 {
460 struct nbr *nbr;
461
462 log_debug("if_del: interface %s", iface->name);
463
464 /* clear lists etc */
465 while ((nbr = LIST_FIRST(&iface->nbr_list)) != NULL)
466 nbr_del(nbr);
467
468 /* XXX rq_list, rp_list */
469
470 free(iface);
471 }
472
473 struct ctl_iface *
if_to_ctl(struct iface * iface)474 if_to_ctl(struct iface *iface)
475 {
476 static struct ctl_iface ictl;
477 struct timeval now;
478
479 memcpy(ictl.name, iface->name, sizeof(ictl.name));
480 memcpy(&ictl.addr, &iface->addr, sizeof(ictl.addr));
481 memcpy(&ictl.mask, &iface->mask, sizeof(ictl.mask));
482
483 ictl.ifindex = iface->ifindex;
484 ictl.state = iface->state;
485 ictl.mtu = iface->mtu;
486
487 ictl.baudrate = iface->baudrate;
488 ictl.flags = iface->flags;
489 ictl.metric = iface->cost;
490 ictl.type = iface->type;
491 ictl.linkstate = iface->linkstate;
492 ictl.passive = iface->passive;
493 ictl.if_type = iface->if_type;
494
495 gettimeofday(&now, NULL);
496
497 if (iface->state != IF_STA_DOWN) {
498 ictl.uptime = now.tv_sec - iface->uptime;
499 } else
500 ictl.uptime = 0;
501
502 return (&ictl);
503 }
504