xref: /openbsd-src/usr.sbin/ospf6d/database.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: database.c,v 1.9 2008/12/28 20:08:31 claudio Exp $ */
2 
3 /*
4  * Copyright (c) 2005 Claudio Jeker <claudio@openbsd.org>
5  * Copyright (c) 2004, 2005, 2007 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/socket.h>
22 #include <netinet/in.h>
23 #include <netinet/in_systm.h>
24 #include <netinet/ip.h>
25 #include <arpa/inet.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29 
30 #include "ospf6d.h"
31 #include "ospf6.h"
32 #include "log.h"
33 #include "ospfe.h"
34 
35 extern struct ospfd_conf	*oeconf;
36 
37 void	db_sum_list_next(struct nbr *);
38 
39 /* database description packet handling */
40 int
41 send_db_description(struct nbr *nbr)
42 {
43 	struct in6_addr		 dst;
44 	struct db_dscrp_hdr	 dd_hdr;
45 	struct lsa_entry	*le, *nle;
46 	struct buf		*buf;
47 	int			 ret = 0;
48 	u_int8_t		 bits = 0;
49 
50 	if ((buf = buf_open(nbr->iface->mtu - sizeof(struct ip))) == NULL)
51 		fatal("send_db_description");
52 
53 	/* OSPF header */
54 	if (gen_ospf_hdr(buf, nbr->iface, PACKET_TYPE_DD))
55 		goto fail;
56 
57 	/* reserve space for database description header */
58 	if (buf_reserve(buf, sizeof(dd_hdr)) == NULL)
59 		goto fail;
60 
61 	switch (nbr->state) {
62 	case NBR_STA_DOWN:
63 	case NBR_STA_ATTEMPT:
64 	case NBR_STA_INIT:
65 	case NBR_STA_2_WAY:
66 	case NBR_STA_SNAP:
67 		log_debug("send_db_description: cannot send packet in state %s,"
68 		    " neighbor ID %s", nbr_state_name(nbr->state),
69 		    inet_ntoa(nbr->id));
70 		ret = -1;
71 		goto done;
72 	case NBR_STA_XSTRT:
73 		bits |= OSPF_DBD_MS | OSPF_DBD_M | OSPF_DBD_I;
74 		nbr->dd_more = 1;
75 		break;
76 	case NBR_STA_XCHNG:
77 		if (nbr->dd_master)
78 			bits |= OSPF_DBD_MS;
79 		else
80 			bits &= ~OSPF_DBD_MS;
81 
82 		if (TAILQ_EMPTY(&nbr->db_sum_list)) {
83 			bits &= ~OSPF_DBD_M;
84 			nbr->dd_more = 0;
85 		} else {
86 			bits |= OSPF_DBD_M;
87 			nbr->dd_more = 1;
88 		}
89 
90 		bits &= ~OSPF_DBD_I;
91 
92 		/* build LSA list, keep space for a possible md5 sum */
93 		for (le = TAILQ_FIRST(&nbr->db_sum_list); le != NULL &&
94 		    buf->wpos + sizeof(struct lsa_hdr) < buf->max -
95 		    MD5_DIGEST_LENGTH; le = nle) {
96 			nbr->dd_end = nle = TAILQ_NEXT(le, entry);
97 			if (buf_add(buf, le->le_lsa, sizeof(struct lsa_hdr)))
98 				goto fail;
99 		}
100 		break;
101 	case NBR_STA_LOAD:
102 	case NBR_STA_FULL:
103 		if (nbr->dd_master)
104 			bits |= OSPF_DBD_MS;
105 		else
106 			bits &= ~OSPF_DBD_MS;
107 		bits &= ~OSPF_DBD_M;
108 		bits &= ~OSPF_DBD_I;
109 
110 		nbr->dd_more = 0;
111 		break;
112 	default:
113 		fatalx("send_db_description: unknown neighbor state");
114 	}
115 
116 	bzero(&dd_hdr, sizeof(dd_hdr));
117 
118 	switch (nbr->iface->type) {
119 	case IF_TYPE_POINTOPOINT:
120 		inet_pton(AF_INET6, AllSPFRouters, &dst);
121 		dd_hdr.iface_mtu = htons(nbr->iface->mtu);
122 		break;
123 	case IF_TYPE_BROADCAST:
124 		dst = nbr->addr;
125 		dd_hdr.iface_mtu = htons(nbr->iface->mtu);
126 		break;
127 	case IF_TYPE_NBMA:
128 	case IF_TYPE_POINTOMULTIPOINT:
129 		/* XXX not supported */
130 		break;
131 	case IF_TYPE_VIRTUALLINK:
132 		dst = nbr->iface->dst;
133 		dd_hdr.iface_mtu = 0;
134 		break;
135 	default:
136 		fatalx("send_db_description: unknown interface type");
137 	}
138 
139 	dd_hdr.opts = htonl(area_ospf_options(area_find(oeconf,
140 	    nbr->iface->area_id)));
141 	dd_hdr.bits = bits;
142 	dd_hdr.dd_seq_num = htonl(nbr->dd_seq_num);
143 
144 	memcpy(buf_seek(buf, sizeof(struct ospf_hdr), sizeof(dd_hdr)),
145 	    &dd_hdr, sizeof(dd_hdr));
146 
147 	/* calculate checksum */
148 	if (upd_ospf_hdr(buf, nbr->iface))
149 		goto fail;
150 
151 	/* transmit packet */
152 	ret = send_packet(nbr->iface, buf->buf, buf->wpos, &dst);
153 done:
154 	buf_free(buf);
155 	return (ret);
156 fail:
157 	log_warn("send_db_description");
158 	buf_free(buf);
159 	return (-1);
160 }
161 
162 void
163 recv_db_description(struct nbr *nbr, char *buf, u_int16_t len)
164 {
165 	struct db_dscrp_hdr	 dd_hdr;
166 	int			 dupe = 0;
167 
168 	if (len < sizeof(dd_hdr)) {
169 		log_warnx("recv_db_description: "
170 		    "bad packet size, neighbor ID %s", inet_ntoa(nbr->id));
171 		return;
172 	}
173 	memcpy(&dd_hdr, buf, sizeof(dd_hdr));
174 	buf += sizeof(dd_hdr);
175 	len -= sizeof(dd_hdr);
176 
177 	/* db description packet sanity checks */
178 	if (ntohs(dd_hdr.iface_mtu) > nbr->iface->mtu) {
179 		log_warnx("recv_db_description: invalid MTU %d sent by "
180 		    "neighbor ID %s, expected %d", ntohs(dd_hdr.iface_mtu),
181 		    inet_ntoa(nbr->id), nbr->iface->mtu);
182 		return;
183 	}
184 
185 	if (nbr->last_rx_options == dd_hdr.opts &&
186 	    nbr->last_rx_bits == dd_hdr.bits &&
187 	    ntohl(dd_hdr.dd_seq_num) == nbr->dd_seq_num - nbr->dd_master ?
188 	    1 : 0) {
189 			log_debug("recv_db_description: dupe");
190 			dupe = 1;
191 	}
192 
193 	switch (nbr->state) {
194 	case NBR_STA_DOWN:
195 	case NBR_STA_ATTEMPT:
196 	case NBR_STA_2_WAY:
197 	case NBR_STA_SNAP:
198 		log_debug("recv_db_description: packet ignored in state %s, "
199 		    "neighbor ID %s", nbr_state_name(nbr->state),
200 		    inet_ntoa(nbr->id));
201 		return;
202 	case NBR_STA_INIT:
203 		/* evaluate dr and bdr after issuing a 2-Way event */
204 		nbr_fsm(nbr, NBR_EVT_2_WAY_RCVD);
205 		if_fsm(nbr->iface, IF_EVT_NBR_CHNG);
206 		if (nbr->state != NBR_STA_XSTRT)
207 			return;
208 		/* FALLTHROUGH */
209 	case NBR_STA_XSTRT:
210 		if (dupe)
211 			return;
212 		/*
213 		 * check bits: either I,M,MS or only M
214 		 */
215 		if (dd_hdr.bits == (OSPF_DBD_I | OSPF_DBD_M | OSPF_DBD_MS)) {
216 			/* if nbr Router ID is larger than own -> slave */
217 			if ((ntohl(nbr->id.s_addr)) >
218 			    ntohl(ospfe_router_id())) {
219 				/* slave */
220 				nbr->dd_master = 0;
221 				nbr->dd_seq_num = ntohl(dd_hdr.dd_seq_num);
222 
223 				/* event negotiation done */
224 				nbr_fsm(nbr, NBR_EVT_NEG_DONE);
225 			}
226 		} else if (!(dd_hdr.bits & (OSPF_DBD_I | OSPF_DBD_MS))) {
227 			/* M only case: we are master */
228 			if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num) {
229 				log_warnx("recv_db_description: invalid "
230 				    "seq num, mine %x his %x",
231 				    nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num));
232 				nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
233 				return;
234 			}
235 			nbr->dd_seq_num++;
236 
237 			/* event negotiation done */
238 			nbr_fsm(nbr, NBR_EVT_NEG_DONE);
239 
240 			/* this packet may already have data so pass it on */
241 			if (len > 0) {
242 				nbr->dd_pending++;
243 				ospfe_imsg_compose_rde(IMSG_DD, nbr->peerid,
244 				    0, buf, len);
245 			}
246 		} else {
247 			/* ignore packet */
248 			log_debug("recv_db_description: packet ignored in "
249 			    "state %s (bad flags), neighbor ID %s",
250 			    nbr_state_name(nbr->state), inet_ntoa(nbr->id));
251 		}
252 		break;
253 	case NBR_STA_XCHNG:
254 	case NBR_STA_LOAD:
255 	case NBR_STA_FULL:
256 		if (dd_hdr.bits & OSPF_DBD_I ||
257 		    !(dd_hdr.bits & OSPF_DBD_MS) == !nbr->dd_master) {
258 			log_warnx("recv_db_description: seq num mismatch, "
259 			    "bad flags");
260 			nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
261 			return;
262 		}
263 
264 		if (nbr->last_rx_options != dd_hdr.opts) {
265 			log_warnx("recv_db_description: seq num mismatch, "
266 			    "bad options");
267 			nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
268 			return;
269 		}
270 
271 		if (dupe) {
272 			if (!nbr->dd_master)
273 				/* retransmit */
274 				start_db_tx_timer(nbr);
275 			return;
276 		}
277 
278 		if (nbr->state != NBR_STA_XCHNG) {
279 			log_warnx("recv_db_description: invalid "
280 			    "seq num, mine %x his %x",
281 			    nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num));
282 			nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
283 			return;
284 		}
285 
286 		/* sanity check dd seq number */
287 		if (nbr->dd_master) {
288 			/* master */
289 			if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num) {
290 				log_warnx("recv_db_description: invalid "
291 				    "seq num, mine %x his %x",
292 				    nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num));
293 				nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
294 				return;
295 			}
296 			nbr->dd_seq_num++;
297 		} else {
298 			/* slave */
299 			if (ntohl(dd_hdr.dd_seq_num) != nbr->dd_seq_num + 1) {
300 				log_warnx("recv_db_description: invalid "
301 				    "seq num, mine %x his %x",
302 				    nbr->dd_seq_num, ntohl(dd_hdr.dd_seq_num));
303 				nbr_fsm(nbr, NBR_EVT_SEQ_NUM_MIS);
304 				return;
305 			}
306 			nbr->dd_seq_num = ntohl(dd_hdr.dd_seq_num);
307 		}
308 
309 		/* forward to RDE and let it decide which LSAs to request */
310 		if (len > 0) {
311 			nbr->dd_pending++;
312 			ospfe_imsg_compose_rde(IMSG_DD, nbr->peerid, 0,
313 			    buf, len);
314 		}
315 
316 		/* next packet */
317 		db_sum_list_next(nbr);
318 		start_db_tx_timer(nbr);
319 
320 		if (!(dd_hdr.bits & OSPF_DBD_M) &&
321 		    TAILQ_EMPTY(&nbr->db_sum_list))
322 			if (!nbr->dd_master || !nbr->dd_more)
323 				nbr_fsm(nbr, NBR_EVT_XCHNG_DONE);
324 		break;
325 	default:
326 		fatalx("recv_db_description: unknown neighbor state");
327 	}
328 
329 	nbr->last_rx_options = dd_hdr.opts;
330 	nbr->last_rx_bits = dd_hdr.bits;
331 }
332 
333 void
334 db_sum_list_add(struct nbr *nbr, struct lsa_hdr *lsa)
335 {
336 	struct lsa_entry	*le;
337 
338 	if ((le = calloc(1, sizeof(*le))) == NULL)
339 		fatal("db_sum_list_add");
340 
341 	TAILQ_INSERT_TAIL(&nbr->db_sum_list, le, entry);
342 	le->le_lsa = lsa;
343 }
344 
345 void
346 db_sum_list_next(struct nbr *nbr)
347 {
348 	struct lsa_entry	*le;
349 
350 	while ((le = TAILQ_FIRST(&nbr->db_sum_list)) != nbr->dd_end) {
351 		TAILQ_REMOVE(&nbr->db_sum_list, le, entry);
352 		free(le->le_lsa);
353 		free(le);
354 	}
355 }
356 
357 void
358 db_sum_list_clr(struct nbr *nbr)
359 {
360 	nbr->dd_end = NULL;
361 	db_sum_list_next(nbr);
362 }
363 
364 /* timers */
365 /* ARGSUSED */
366 void
367 db_tx_timer(int fd, short event, void *arg)
368 {
369 	struct nbr *nbr = arg;
370 	struct timeval tv;
371 
372 	switch (nbr->state) {
373 	case NBR_STA_DOWN:
374 	case NBR_STA_ATTEMPT:
375 	case NBR_STA_INIT:
376 	case NBR_STA_2_WAY:
377 	case NBR_STA_SNAP:
378 		return ;
379 	case NBR_STA_XSTRT:
380 	case NBR_STA_XCHNG:
381 	case NBR_STA_LOAD:
382 	case NBR_STA_FULL:
383 		send_db_description(nbr);
384 		break;
385 	default:
386 		log_debug("db_tx_timer: unknown neighbor state, "
387 		    "neighbor ID %s", inet_ntoa(nbr->id));
388 		break;
389 	}
390 
391 	/* reschedule db_tx_timer but only in master mode */
392 	if (nbr->dd_master) {
393 		timerclear(&tv);
394 		tv.tv_sec = nbr->iface->rxmt_interval;
395 		if (evtimer_add(&nbr->db_tx_timer, &tv) == -1)
396 			fatal("db_tx_timer");
397 	}
398 }
399 
400 void
401 start_db_tx_timer(struct nbr *nbr)
402 {
403 	struct timeval	tv;
404 
405 	if (nbr == nbr->iface->self)
406 		return;
407 
408 	timerclear(&tv);
409 	if (evtimer_add(&nbr->db_tx_timer, &tv) == -1)
410 		fatal("start_db_tx_timer");
411 }
412 
413 void
414 stop_db_tx_timer(struct nbr *nbr)
415 {
416 	if (nbr == nbr->iface->self)
417 		return;
418 
419 	if (evtimer_del(&nbr->db_tx_timer) == -1)
420 		fatal("stop_db_tx_timer");
421 }
422