1: /*
2: * OSPF Sending and Receiving OSPF Packets.
3: * Copyright (C) 1999, 2000 Toshiaki Takada
4: *
5: * This file is part of GNU Zebra.
6: *
7: * GNU Zebra is free software; you can redistribute it and/or modify it
8: * under the terms of the GNU General Public License as published by the
9: * Free Software Foundation; either version 2, or (at your option) any
10: * later version.
11: *
12: * GNU Zebra is distributed in the hope that it will be useful, but
13: * WITHOUT ANY WARRANTY; without even the implied warranty of
14: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15: * General Public License for more details.
16: *
17: * You should have received a copy of the GNU General Public License
18: * along with GNU Zebra; see the file COPYING. If not, write to the Free
19: * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
20: * 02111-1307, USA.
21: */
22:
23: #include <zebra.h>
24:
25: #include "thread.h"
26: #include "memory.h"
27: #include "linklist.h"
28: #include "prefix.h"
29: #include "if.h"
30: #include "table.h"
31: #include "sockunion.h"
32: #include "stream.h"
33: #include "log.h"
34: #include "sockopt.h"
35: #include "checksum.h"
36: #include "md5.h"
37:
38: #include "ospfd/ospfd.h"
39: #include "ospfd/ospf_network.h"
40: #include "ospfd/ospf_interface.h"
41: #include "ospfd/ospf_ism.h"
42: #include "ospfd/ospf_asbr.h"
43: #include "ospfd/ospf_lsa.h"
44: #include "ospfd/ospf_lsdb.h"
45: #include "ospfd/ospf_neighbor.h"
46: #include "ospfd/ospf_nsm.h"
47: #include "ospfd/ospf_packet.h"
48: #include "ospfd/ospf_spf.h"
49: #include "ospfd/ospf_flood.h"
50: #include "ospfd/ospf_dump.h"
51:
52: /* Packet Type String. */
53: const char *ospf_packet_type_str[] =
54: {
55: "unknown",
56: "Hello",
57: "Database Description",
58: "Link State Request",
59: "Link State Update",
60: "Link State Acknowledgment",
61: };
62:
63: /* OSPF authentication checking function */
64: static int
65: ospf_auth_type (struct ospf_interface *oi)
66: {
67: int auth_type;
68:
69: if (OSPF_IF_PARAM (oi, auth_type) == OSPF_AUTH_NOTSET)
70: auth_type = oi->area->auth_type;
71: else
72: auth_type = OSPF_IF_PARAM (oi, auth_type);
73:
74: /* Handle case where MD5 key list is not configured aka Cisco */
75: if (auth_type == OSPF_AUTH_CRYPTOGRAPHIC &&
76: list_isempty (OSPF_IF_PARAM (oi, auth_crypt)))
77: return OSPF_AUTH_NULL;
78:
79: return auth_type;
80:
81: }
82:
83: struct ospf_packet *
84: ospf_packet_new (size_t size)
85: {
86: struct ospf_packet *new;
87:
88: new = XCALLOC (MTYPE_OSPF_PACKET, sizeof (struct ospf_packet));
89: new->s = stream_new (size);
90:
91: return new;
92: }
93:
94: void
95: ospf_packet_free (struct ospf_packet *op)
96: {
97: if (op->s)
98: stream_free (op->s);
99:
100: XFREE (MTYPE_OSPF_PACKET, op);
101:
102: op = NULL;
103: }
104:
105: struct ospf_fifo *
106: ospf_fifo_new ()
107: {
108: struct ospf_fifo *new;
109:
110: new = XCALLOC (MTYPE_OSPF_FIFO, sizeof (struct ospf_fifo));
111: return new;
112: }
113:
114: /* Add new packet to fifo. */
115: void
116: ospf_fifo_push (struct ospf_fifo *fifo, struct ospf_packet *op)
117: {
118: if (fifo->tail)
119: fifo->tail->next = op;
120: else
121: fifo->head = op;
122:
123: fifo->tail = op;
124:
125: fifo->count++;
126: }
127:
128: /* Add new packet to head of fifo. */
129: static void
130: ospf_fifo_push_head (struct ospf_fifo *fifo, struct ospf_packet *op)
131: {
132: op->next = fifo->head;
133:
134: if (fifo->tail == NULL)
135: fifo->tail = op;
136:
137: fifo->head = op;
138:
139: fifo->count++;
140: }
141:
142: /* Delete first packet from fifo. */
143: struct ospf_packet *
144: ospf_fifo_pop (struct ospf_fifo *fifo)
145: {
146: struct ospf_packet *op;
147:
148: op = fifo->head;
149:
150: if (op)
151: {
152: fifo->head = op->next;
153:
154: if (fifo->head == NULL)
155: fifo->tail = NULL;
156:
157: fifo->count--;
158: }
159:
160: return op;
161: }
162:
163: /* Return first fifo entry. */
164: struct ospf_packet *
165: ospf_fifo_head (struct ospf_fifo *fifo)
166: {
167: return fifo->head;
168: }
169:
170: /* Flush ospf packet fifo. */
171: void
172: ospf_fifo_flush (struct ospf_fifo *fifo)
173: {
174: struct ospf_packet *op;
175: struct ospf_packet *next;
176:
177: for (op = fifo->head; op; op = next)
178: {
179: next = op->next;
180: ospf_packet_free (op);
181: }
182: fifo->head = fifo->tail = NULL;
183: fifo->count = 0;
184: }
185:
186: /* Free ospf packet fifo. */
187: void
188: ospf_fifo_free (struct ospf_fifo *fifo)
189: {
190: ospf_fifo_flush (fifo);
191:
192: XFREE (MTYPE_OSPF_FIFO, fifo);
193: }
194:
195: void
196: ospf_packet_add (struct ospf_interface *oi, struct ospf_packet *op)
197: {
198: if (!oi->obuf)
199: {
200: zlog_err("ospf_packet_add(interface %s in state %d [%s], packet type %s, "
201: "destination %s) called with NULL obuf, ignoring "
202: "(please report this bug)!\n",
203: IF_NAME(oi), oi->state, LOOKUP (ospf_ism_state_msg, oi->state),
204: ospf_packet_type_str[stream_getc_from(op->s, 1)],
205: inet_ntoa (op->dst));
206: return;
207: }
208:
209: /* Add packet to end of queue. */
210: ospf_fifo_push (oi->obuf, op);
211:
212: /* Debug of packet fifo*/
213: /* ospf_fifo_debug (oi->obuf); */
214: }
215:
216: static void
217: ospf_packet_add_top (struct ospf_interface *oi, struct ospf_packet *op)
218: {
219: if (!oi->obuf)
220: {
221: zlog_err("ospf_packet_add(interface %s in state %d [%s], packet type %s, "
222: "destination %s) called with NULL obuf, ignoring "
223: "(please report this bug)!\n",
224: IF_NAME(oi), oi->state, LOOKUP (ospf_ism_state_msg, oi->state),
225: ospf_packet_type_str[stream_getc_from(op->s, 1)],
226: inet_ntoa (op->dst));
227: return;
228: }
229:
230: /* Add packet to head of queue. */
231: ospf_fifo_push_head (oi->obuf, op);
232:
233: /* Debug of packet fifo*/
234: /* ospf_fifo_debug (oi->obuf); */
235: }
236:
237: void
238: ospf_packet_delete (struct ospf_interface *oi)
239: {
240: struct ospf_packet *op;
241:
242: op = ospf_fifo_pop (oi->obuf);
243:
244: if (op)
245: ospf_packet_free (op);
246: }
247:
248: struct ospf_packet *
249: ospf_packet_dup (struct ospf_packet *op)
250: {
251: struct ospf_packet *new;
252:
253: if (stream_get_endp(op->s) != op->length)
254: /* XXX size_t */
255: zlog_warn ("ospf_packet_dup stream %lu ospf_packet %u size mismatch",
256: (u_long)STREAM_SIZE(op->s), op->length);
257:
258: /* Reserve space for MD5 authentication that may be added later. */
259: new = ospf_packet_new (stream_get_endp(op->s) + OSPF_AUTH_MD5_SIZE);
260: stream_copy (new->s, op->s);
261:
262: new->dst = op->dst;
263: new->length = op->length;
264:
265: return new;
266: }
267:
268: /* XXX inline */
269: static inline unsigned int
270: ospf_packet_authspace (struct ospf_interface *oi)
271: {
272: int auth = 0;
273:
274: if ( ospf_auth_type (oi) == OSPF_AUTH_CRYPTOGRAPHIC)
275: auth = OSPF_AUTH_MD5_SIZE;
276:
277: return auth;
278: }
279:
280: static unsigned int
281: ospf_packet_max (struct ospf_interface *oi)
282: {
283: int max;
284:
285: max = oi->ifp->mtu - ospf_packet_authspace(oi);
286:
287: max -= (OSPF_HEADER_SIZE + sizeof (struct ip));
288:
289: return max;
290: }
291:
292:
293: static int
294: ospf_check_md5_digest (struct ospf_interface *oi, struct stream *s,
295: u_int16_t length)
296: {
297: unsigned char *ibuf;
298: MD5_CTX ctx;
299: unsigned char digest[OSPF_AUTH_MD5_SIZE];
300: unsigned char *pdigest;
301: struct crypt_key *ck;
302: struct ospf_header *ospfh;
303: struct ospf_neighbor *nbr;
304:
305:
306: ibuf = STREAM_PNT (s);
307: ospfh = (struct ospf_header *) ibuf;
308:
309: /* Get pointer to the end of the packet. */
310: pdigest = ibuf + length;
311:
312: /* Get secret key. */
313: ck = ospf_crypt_key_lookup (OSPF_IF_PARAM (oi, auth_crypt),
314: ospfh->u.crypt.key_id);
315: if (ck == NULL)
316: {
317: zlog_warn ("interface %s: ospf_check_md5 no key %d",
318: IF_NAME (oi), ospfh->u.crypt.key_id);
319: return 0;
320: }
321:
322: /* check crypto seqnum. */
323: nbr = ospf_nbr_lookup_by_routerid (oi->nbrs, &ospfh->router_id);
324:
325: if (nbr && ntohl(nbr->crypt_seqnum) > ntohl(ospfh->u.crypt.crypt_seqnum))
326: {
327: zlog_warn ("interface %s: ospf_check_md5 bad sequence %d (expect %d)",
328: IF_NAME (oi),
329: ntohl(ospfh->u.crypt.crypt_seqnum),
330: ntohl(nbr->crypt_seqnum));
331: return 0;
332: }
333:
334: /* Generate a digest for the ospf packet - their digest + our digest. */
335: memset(&ctx, 0, sizeof(ctx));
336: MD5Init(&ctx);
337: MD5Update(&ctx, ibuf, length);
338: MD5Update(&ctx, ck->auth_key, OSPF_AUTH_MD5_SIZE);
339: MD5Final(digest, &ctx);
340:
341: /* compare the two */
342: if (memcmp (pdigest, digest, OSPF_AUTH_MD5_SIZE))
343: {
344: zlog_warn ("interface %s: ospf_check_md5 checksum mismatch",
345: IF_NAME (oi));
346: return 0;
347: }
348:
349: /* save neighbor's crypt_seqnum */
350: if (nbr)
351: nbr->crypt_seqnum = ospfh->u.crypt.crypt_seqnum;
352: return 1;
353: }
354:
355: /* This function is called from ospf_write(), it will detect the
356: authentication scheme and if it is MD5, it will change the sequence
357: and update the MD5 digest. */
358: static int
359: ospf_make_md5_digest (struct ospf_interface *oi, struct ospf_packet *op)
360: {
361: struct ospf_header *ospfh;
362: unsigned char digest[OSPF_AUTH_MD5_SIZE];
363: MD5_CTX ctx;
364: void *ibuf;
365: u_int32_t t;
366: struct crypt_key *ck;
367: const u_int8_t *auth_key;
368:
369: ibuf = STREAM_DATA (op->s);
370: ospfh = (struct ospf_header *) ibuf;
371:
372: if (ntohs (ospfh->auth_type) != OSPF_AUTH_CRYPTOGRAPHIC)
373: return 0;
374:
375: /* We do this here so when we dup a packet, we don't have to
376: waste CPU rewriting other headers.
377:
378: Note that quagga_time /deliberately/ is not used here */
379: t = (time(NULL) & 0xFFFFFFFF);
380: if (t > oi->crypt_seqnum)
381: oi->crypt_seqnum = t;
382: else
383: oi->crypt_seqnum++;
384:
385: ospfh->u.crypt.crypt_seqnum = htonl (oi->crypt_seqnum);
386:
387: /* Get MD5 Authentication key from auth_key list. */
388: if (list_isempty (OSPF_IF_PARAM (oi, auth_crypt)))
389: auth_key = (const u_int8_t *) "";
390: else
391: {
392: ck = listgetdata (listtail(OSPF_IF_PARAM (oi, auth_crypt)));
393: auth_key = ck->auth_key;
394: }
395:
396: /* Generate a digest for the entire packet + our secret key. */
397: memset(&ctx, 0, sizeof(ctx));
398: MD5Init(&ctx);
399: MD5Update(&ctx, ibuf, ntohs (ospfh->length));
400: MD5Update(&ctx, auth_key, OSPF_AUTH_MD5_SIZE);
401: MD5Final(digest, &ctx);
402:
403: /* Append md5 digest to the end of the stream. */
404: stream_put (op->s, digest, OSPF_AUTH_MD5_SIZE);
405:
406: /* We do *NOT* increment the OSPF header length. */
407: op->length = ntohs (ospfh->length) + OSPF_AUTH_MD5_SIZE;
408:
409: if (stream_get_endp(op->s) != op->length)
410: /* XXX size_t */
411: zlog_warn("ospf_make_md5_digest: length mismatch stream %lu ospf_packet %u",
412: (u_long)stream_get_endp(op->s), op->length);
413:
414: return OSPF_AUTH_MD5_SIZE;
415: }
416:
417:
418: static int
419: ospf_ls_req_timer (struct thread *thread)
420: {
421: struct ospf_neighbor *nbr;
422:
423: nbr = THREAD_ARG (thread);
424: nbr->t_ls_req = NULL;
425:
426: /* Send Link State Request. */
427: if (ospf_ls_request_count (nbr))
428: ospf_ls_req_send (nbr);
429:
430: /* Set Link State Request retransmission timer. */
431: OSPF_NSM_TIMER_ON (nbr->t_ls_req, ospf_ls_req_timer, nbr->v_ls_req);
432:
433: return 0;
434: }
435:
436: void
437: ospf_ls_req_event (struct ospf_neighbor *nbr)
438: {
439: if (nbr->t_ls_req)
440: {
441: thread_cancel (nbr->t_ls_req);
442: nbr->t_ls_req = NULL;
443: }
444: nbr->t_ls_req = thread_add_event (master, ospf_ls_req_timer, nbr, 0);
445: }
446:
447: /* Cyclic timer function. Fist registered in ospf_nbr_new () in
448: ospf_neighbor.c */
449: int
450: ospf_ls_upd_timer (struct thread *thread)
451: {
452: struct ospf_neighbor *nbr;
453:
454: nbr = THREAD_ARG (thread);
455: nbr->t_ls_upd = NULL;
456:
457: /* Send Link State Update. */
458: if (ospf_ls_retransmit_count (nbr) > 0)
459: {
460: struct list *update;
461: struct ospf_lsdb *lsdb;
462: int i;
463: int retransmit_interval;
464:
465: retransmit_interval = OSPF_IF_PARAM (nbr->oi, retransmit_interval);
466:
467: lsdb = &nbr->ls_rxmt;
468: update = list_new ();
469:
470: for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
471: {
472: struct route_table *table = lsdb->type[i].db;
473: struct route_node *rn;
474:
475: for (rn = route_top (table); rn; rn = route_next (rn))
476: {
477: struct ospf_lsa *lsa;
478:
479: if ((lsa = rn->info) != NULL)
480: /* Don't retransmit an LSA if we received it within
481: the last RxmtInterval seconds - this is to allow the
482: neighbour a chance to acknowledge the LSA as it may
483: have ben just received before the retransmit timer
484: fired. This is a small tweak to what is in the RFC,
485: but it will cut out out a lot of retransmit traffic
486: - MAG */
487: if (tv_cmp (tv_sub (recent_relative_time (), lsa->tv_recv),
488: int2tv (retransmit_interval)) >= 0)
489: listnode_add (update, rn->info);
490: }
491: }
492:
493: if (listcount (update) > 0)
494: ospf_ls_upd_send (nbr, update, OSPF_SEND_PACKET_DIRECT);
495: list_delete (update);
496: }
497:
498: /* Set LS Update retransmission timer. */
499: OSPF_NSM_TIMER_ON (nbr->t_ls_upd, ospf_ls_upd_timer, nbr->v_ls_upd);
500:
501: return 0;
502: }
503:
504: int
505: ospf_ls_ack_timer (struct thread *thread)
506: {
507: struct ospf_interface *oi;
508:
509: oi = THREAD_ARG (thread);
510: oi->t_ls_ack = NULL;
511:
512: /* Send Link State Acknowledgment. */
513: if (listcount (oi->ls_ack) > 0)
514: ospf_ls_ack_send_delayed (oi);
515:
516: /* Set LS Ack timer. */
517: OSPF_ISM_TIMER_ON (oi->t_ls_ack, ospf_ls_ack_timer, oi->v_ls_ack);
518:
519: return 0;
520: }
521:
522: #ifdef WANT_OSPF_WRITE_FRAGMENT
523: static void
524: ospf_write_frags (int fd, struct ospf_packet *op, struct ip *iph,
525: struct msghdr *msg, unsigned int maxdatasize,
526: unsigned int mtu, int flags, u_char type)
527: {
528: #define OSPF_WRITE_FRAG_SHIFT 3
529: u_int16_t offset;
530: struct iovec *iovp;
531: int ret;
532:
533: assert ( op->length == stream_get_endp(op->s) );
534: assert (msg->msg_iovlen == 2);
535:
536: /* we can but try.
537: *
538: * SunOS, BSD and BSD derived kernels likely will clear ip_id, as
539: * well as the IP_MF flag, making this all quite pointless.
540: *
541: * However, for a system on which IP_MF is left alone, and ip_id left
542: * alone or else which sets same ip_id for each fragment this might
543: * work, eg linux.
544: *
545: * XXX-TODO: It would be much nicer to have the kernel's use their
546: * existing fragmentation support to do this for us. Bugs/RFEs need to
547: * be raised against the various kernels.
548: */
549:
550: /* set More Frag */
551: iph->ip_off |= IP_MF;
552:
553: /* ip frag offset is expressed in units of 8byte words */
554: offset = maxdatasize >> OSPF_WRITE_FRAG_SHIFT;
555:
556: iovp = &msg->msg_iov[1];
557:
558: while ( (stream_get_endp(op->s) - stream_get_getp (op->s))
559: > maxdatasize )
560: {
561: /* data length of this frag is to next offset value */
562: iovp->iov_len = offset << OSPF_WRITE_FRAG_SHIFT;
563: iph->ip_len = iovp->iov_len + sizeof (struct ip);
564: assert (iph->ip_len <= mtu);
565:
566: sockopt_iphdrincl_swab_htosys (iph);
567:
568: ret = sendmsg (fd, msg, flags);
569:
570: sockopt_iphdrincl_swab_systoh (iph);
571:
572: if (ret < 0)
573: zlog_warn ("*** ospf_write_frags: sendmsg failed to %s,"
574: " id %d, off %d, len %d, mtu %u failed with %s",
575: inet_ntoa (iph->ip_dst),
576: iph->ip_id,
577: iph->ip_off,
578: iph->ip_len,
579: mtu,
580: safe_strerror (errno));
581:
582: if (IS_DEBUG_OSPF_PACKET (type - 1, SEND))
583: {
584: zlog_debug ("ospf_write_frags: sent id %d, off %d, len %d to %s\n",
585: iph->ip_id, iph->ip_off, iph->ip_len,
586: inet_ntoa (iph->ip_dst));
587: if (IS_DEBUG_OSPF_PACKET (type - 1, DETAIL))
588: {
589: zlog_debug ("-----------------IP Header Dump----------------------");
590: ospf_ip_header_dump (iph);
591: zlog_debug ("-----------------------------------------------------");
592: }
593: }
594:
595: iph->ip_off += offset;
596: stream_forward_getp (op->s, iovp->iov_len);
597: iovp->iov_base = STREAM_PNT (op->s);
598: }
599:
600: /* setup for final fragment */
601: iovp->iov_len = stream_get_endp(op->s) - stream_get_getp (op->s);
602: iph->ip_len = iovp->iov_len + sizeof (struct ip);
603: iph->ip_off &= (~IP_MF);
604: }
605: #endif /* WANT_OSPF_WRITE_FRAGMENT */
606:
607: static int
608: ospf_write (struct thread *thread)
609: {
610: struct ospf *ospf = THREAD_ARG (thread);
611: struct ospf_interface *oi;
612: struct ospf_packet *op;
613: struct sockaddr_in sa_dst;
614: struct ip iph;
615: struct msghdr msg;
616: struct iovec iov[2];
617: u_char type;
618: int ret;
619: int flags = 0;
620: struct listnode *node;
621: #ifdef WANT_OSPF_WRITE_FRAGMENT
622: static u_int16_t ipid = 0;
623: #endif /* WANT_OSPF_WRITE_FRAGMENT */
624: u_int16_t maxdatasize;
625: #define OSPF_WRITE_IPHL_SHIFT 2
626:
627: ospf->t_write = NULL;
628:
629: node = listhead (ospf->oi_write_q);
630: assert (node);
631: oi = listgetdata (node);
632: assert (oi);
633:
634: #ifdef WANT_OSPF_WRITE_FRAGMENT
635: /* seed ipid static with low order bits of time */
636: if (ipid == 0)
637: ipid = (time(NULL) & 0xffff);
638: #endif /* WANT_OSPF_WRITE_FRAGMENT */
639:
640: /* convenience - max OSPF data per packet,
641: * and reliability - not more data, than our
642: * socket can accept
643: */
644: maxdatasize = MIN (oi->ifp->mtu, ospf->maxsndbuflen) -
645: sizeof (struct ip);
646:
647: /* Get one packet from queue. */
648: op = ospf_fifo_head (oi->obuf);
649: assert (op);
650: assert (op->length >= OSPF_HEADER_SIZE);
651:
652: if (op->dst.s_addr == htonl (OSPF_ALLSPFROUTERS)
653: || op->dst.s_addr == htonl (OSPF_ALLDROUTERS))
654: ospf_if_ipmulticast (ospf, oi->address, oi->ifp->ifindex);
655:
656: /* Rewrite the md5 signature & update the seq */
657: ospf_make_md5_digest (oi, op);
658:
659: /* Retrieve OSPF packet type. */
660: stream_set_getp (op->s, 1);
661: type = stream_getc (op->s);
662:
663: /* reset get pointer */
664: stream_set_getp (op->s, 0);
665:
666: memset (&iph, 0, sizeof (struct ip));
667: memset (&sa_dst, 0, sizeof (sa_dst));
668:
669: sa_dst.sin_family = AF_INET;
670: #ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
671: sa_dst.sin_len = sizeof(sa_dst);
672: #endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */
673: sa_dst.sin_addr = op->dst;
674: sa_dst.sin_port = htons (0);
675:
676: /* Set DONTROUTE flag if dst is unicast. */
677: if (oi->type != OSPF_IFTYPE_VIRTUALLINK)
678: if (!IN_MULTICAST (htonl (op->dst.s_addr)))
679: flags = MSG_DONTROUTE;
680:
681: iph.ip_hl = sizeof (struct ip) >> OSPF_WRITE_IPHL_SHIFT;
682: /* it'd be very strange for header to not be 4byte-word aligned but.. */
683: if ( sizeof (struct ip)
684: > (unsigned int)(iph.ip_hl << OSPF_WRITE_IPHL_SHIFT) )
685: iph.ip_hl++; /* we presume sizeof struct ip cant overflow ip_hl.. */
686:
687: iph.ip_v = IPVERSION;
688: iph.ip_tos = IPTOS_PREC_INTERNETCONTROL;
689: iph.ip_len = (iph.ip_hl << OSPF_WRITE_IPHL_SHIFT) + op->length;
690:
691: #if defined(__DragonFly__)
692: /*
693: * DragonFly's raw socket expects ip_len/ip_off in network byte order.
694: */
695: iph.ip_len = htons(iph.ip_len);
696: #endif
697:
698: #ifdef WANT_OSPF_WRITE_FRAGMENT
699: /* XXX-MT: not thread-safe at all..
700: * XXX: this presumes this is only programme sending OSPF packets
701: * otherwise, no guarantee ipid will be unique
702: */
703: iph.ip_id = ++ipid;
704: #endif /* WANT_OSPF_WRITE_FRAGMENT */
705:
706: iph.ip_off = 0;
707: if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
708: iph.ip_ttl = OSPF_VL_IP_TTL;
709: else
710: iph.ip_ttl = OSPF_IP_TTL;
711: iph.ip_p = IPPROTO_OSPFIGP;
712: iph.ip_sum = 0;
713: iph.ip_src.s_addr = oi->address->u.prefix4.s_addr;
714: iph.ip_dst.s_addr = op->dst.s_addr;
715:
716: memset (&msg, 0, sizeof (msg));
717: msg.msg_name = (caddr_t) &sa_dst;
718: msg.msg_namelen = sizeof (sa_dst);
719: msg.msg_iov = iov;
720: msg.msg_iovlen = 2;
721: iov[0].iov_base = (char*)&iph;
722: iov[0].iov_len = iph.ip_hl << OSPF_WRITE_IPHL_SHIFT;
723: iov[1].iov_base = STREAM_PNT (op->s);
724: iov[1].iov_len = op->length;
725:
726: /* Sadly we can not rely on kernels to fragment packets because of either
727: * IP_HDRINCL and/or multicast destination being set.
728: */
729: #ifdef WANT_OSPF_WRITE_FRAGMENT
730: if ( op->length > maxdatasize )
731: ospf_write_frags (ospf->fd, op, &iph, &msg, maxdatasize,
732: oi->ifp->mtu, flags, type);
733: #endif /* WANT_OSPF_WRITE_FRAGMENT */
734:
735: /* send final fragment (could be first) */
736: sockopt_iphdrincl_swab_htosys (&iph);
737: ret = sendmsg (ospf->fd, &msg, flags);
738: sockopt_iphdrincl_swab_systoh (&iph);
739:
740: if (ret < 0)
741: zlog_warn ("*** sendmsg in ospf_write failed to %s, "
742: "id %d, off %d, len %d, interface %s, mtu %u: %s",
743: inet_ntoa (iph.ip_dst), iph.ip_id, iph.ip_off, iph.ip_len,
744: oi->ifp->name, oi->ifp->mtu, safe_strerror (errno));
745:
746: /* Show debug sending packet. */
747: if (IS_DEBUG_OSPF_PACKET (type - 1, SEND))
748: {
749: if (IS_DEBUG_OSPF_PACKET (type - 1, DETAIL))
750: {
751: zlog_debug ("-----------------------------------------------------");
752: ospf_ip_header_dump (&iph);
753: stream_set_getp (op->s, 0);
754: ospf_packet_dump (op->s);
755: }
756:
757: zlog_debug ("%s sent to [%s] via [%s].",
758: ospf_packet_type_str[type], inet_ntoa (op->dst),
759: IF_NAME (oi));
760:
761: if (IS_DEBUG_OSPF_PACKET (type - 1, DETAIL))
762: zlog_debug ("-----------------------------------------------------");
763: }
764:
765: /* Now delete packet from queue. */
766: ospf_packet_delete (oi);
767:
768: if (ospf_fifo_head (oi->obuf) == NULL)
769: {
770: oi->on_write_q = 0;
771: list_delete_node (ospf->oi_write_q, node);
772: }
773:
774: /* If packets still remain in queue, call write thread. */
775: if (!list_isempty (ospf->oi_write_q))
776: ospf->t_write =
777: thread_add_write (master, ospf_write, ospf, ospf->fd);
778:
779: return 0;
780: }
781:
782: /* OSPF Hello message read -- RFC2328 Section 10.5. */
783: static void
784: ospf_hello (struct ip *iph, struct ospf_header *ospfh,
785: struct stream * s, struct ospf_interface *oi, int size)
786: {
787: struct ospf_hello *hello;
788: struct ospf_neighbor *nbr;
789: int old_state;
790: struct prefix p;
791:
792: /* increment statistics. */
793: oi->hello_in++;
794:
795: hello = (struct ospf_hello *) STREAM_PNT (s);
796:
797: /* If Hello is myself, silently discard. */
798: if (IPV4_ADDR_SAME (&ospfh->router_id, &oi->ospf->router_id))
799: {
800: if (IS_DEBUG_OSPF_PACKET (ospfh->type - 1, RECV))
801: {
802: zlog_debug ("ospf_header[%s/%s]: selforiginated, "
803: "dropping.",
804: ospf_packet_type_str[ospfh->type],
805: inet_ntoa (iph->ip_src));
806: }
807: return;
808: }
809:
810: /* get neighbor prefix. */
811: p.family = AF_INET;
812: p.prefixlen = ip_masklen (hello->network_mask);
813: p.u.prefix4 = iph->ip_src;
814:
815: /* Compare network mask. */
816: /* Checking is ignored for Point-to-Point and Virtual link. */
817: if (oi->type != OSPF_IFTYPE_POINTOPOINT
818: && oi->type != OSPF_IFTYPE_VIRTUALLINK)
819: if (oi->address->prefixlen != p.prefixlen)
820: {
821: zlog_warn ("Packet %s [Hello:RECV]: NetworkMask mismatch on %s (configured prefix length is %d, but hello packet indicates %d).",
822: inet_ntoa(ospfh->router_id), IF_NAME(oi),
823: (int)oi->address->prefixlen, (int)p.prefixlen);
824: return;
825: }
826:
827: /* Compare Router Dead Interval. */
828: if (OSPF_IF_PARAM (oi, v_wait) != ntohl (hello->dead_interval))
829: {
830: zlog_warn ("Packet %s [Hello:RECV]: RouterDeadInterval mismatch "
831: "(expected %u, but received %u).",
832: inet_ntoa(ospfh->router_id),
833: OSPF_IF_PARAM(oi, v_wait), ntohl(hello->dead_interval));
834: return;
835: }
836:
837: /* Compare Hello Interval - ignored if fast-hellos are set. */
838: if (OSPF_IF_PARAM (oi, fast_hello) == 0)
839: {
840: if (OSPF_IF_PARAM (oi, v_hello) != ntohs (hello->hello_interval))
841: {
842: zlog_warn ("Packet %s [Hello:RECV]: HelloInterval mismatch "
843: "(expected %u, but received %u).",
844: inet_ntoa(ospfh->router_id),
845: OSPF_IF_PARAM(oi, v_hello), ntohs(hello->hello_interval));
846: return;
847: }
848: }
849:
850: if (IS_DEBUG_OSPF_EVENT)
851: zlog_debug ("Packet %s [Hello:RECV]: Options %s",
852: inet_ntoa (ospfh->router_id),
853: ospf_options_dump (hello->options));
854:
855: /* Compare options. */
856: #define REJECT_IF_TBIT_ON 1 /* XXX */
857: #ifdef REJECT_IF_TBIT_ON
858: if (CHECK_FLAG (hello->options, OSPF_OPTION_T))
859: {
860: /*
861: * This router does not support non-zero TOS.
862: * Drop this Hello packet not to establish neighbor relationship.
863: */
864: zlog_warn ("Packet %s [Hello:RECV]: T-bit on, drop it.",
865: inet_ntoa (ospfh->router_id));
866: return;
867: }
868: #endif /* REJECT_IF_TBIT_ON */
869:
870: #ifdef HAVE_OPAQUE_LSA
871: if (CHECK_FLAG (oi->ospf->config, OSPF_OPAQUE_CAPABLE)
872: && CHECK_FLAG (hello->options, OSPF_OPTION_O))
873: {
874: /*
875: * This router does know the correct usage of O-bit
876: * the bit should be set in DD packet only.
877: */
878: zlog_warn ("Packet %s [Hello:RECV]: O-bit abuse?",
879: inet_ntoa (ospfh->router_id));
880: #ifdef STRICT_OBIT_USAGE_CHECK
881: return; /* Reject this packet. */
882: #else /* STRICT_OBIT_USAGE_CHECK */
883: UNSET_FLAG (hello->options, OSPF_OPTION_O); /* Ignore O-bit. */
884: #endif /* STRICT_OBIT_USAGE_CHECK */
885: }
886: #endif /* HAVE_OPAQUE_LSA */
887:
888: /* new for NSSA is to ensure that NP is on and E is off */
889:
890: if (oi->area->external_routing == OSPF_AREA_NSSA)
891: {
892: if (! (CHECK_FLAG (OPTIONS (oi), OSPF_OPTION_NP)
893: && CHECK_FLAG (hello->options, OSPF_OPTION_NP)
894: && ! CHECK_FLAG (OPTIONS (oi), OSPF_OPTION_E)
895: && ! CHECK_FLAG (hello->options, OSPF_OPTION_E)))
896: {
897: zlog_warn ("NSSA-Packet-%s[Hello:RECV]: my options: %x, his options %x", inet_ntoa (ospfh->router_id), OPTIONS (oi), hello->options);
898: return;
899: }
900: if (IS_DEBUG_OSPF_NSSA)
901: zlog_debug ("NSSA-Hello:RECV:Packet from %s:", inet_ntoa(ospfh->router_id));
902: }
903: else
904: /* The setting of the E-bit found in the Hello Packet's Options
905: field must match this area's ExternalRoutingCapability A
906: mismatch causes processing to stop and the packet to be
907: dropped. The setting of the rest of the bits in the Hello
908: Packet's Options field should be ignored. */
909: if (CHECK_FLAG (OPTIONS (oi), OSPF_OPTION_E) !=
910: CHECK_FLAG (hello->options, OSPF_OPTION_E))
911: {
912: zlog_warn ("Packet %s [Hello:RECV]: my options: %x, his options %x",
913: inet_ntoa(ospfh->router_id), OPTIONS (oi), hello->options);
914: return;
915: }
916:
917: /* get neighbour struct */
918: nbr = ospf_nbr_get (oi, ospfh, iph, &p);
919:
920: /* neighbour must be valid, ospf_nbr_get creates if none existed */
921: assert (nbr);
922:
923: old_state = nbr->state;
924:
925: /* Add event to thread. */
926: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_PacketReceived);
927:
928: /* RFC2328 Section 9.5.1
929: If the router is not eligible to become Designated Router,
930: (snip) It must also send an Hello Packet in reply to an
931: Hello Packet received from any eligible neighbor (other than
932: the current Designated Router and Backup Designated Router). */
933: if (oi->type == OSPF_IFTYPE_NBMA)
934: if (PRIORITY(oi) == 0 && hello->priority > 0
935: && IPV4_ADDR_CMP(&DR(oi), &iph->ip_src)
936: && IPV4_ADDR_CMP(&BDR(oi), &iph->ip_src))
937: OSPF_NSM_TIMER_ON (nbr->t_hello_reply, ospf_hello_reply_timer,
938: OSPF_HELLO_REPLY_DELAY);
939:
940: /* on NBMA network type, it happens to receive bidirectional Hello packet
941: without advance 1-Way Received event.
942: To avoid incorrect DR-seletion, raise 1-Way Received event.*/
943: if (oi->type == OSPF_IFTYPE_NBMA &&
944: (old_state == NSM_Down || old_state == NSM_Attempt))
945: {
946: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_OneWayReceived);
947: nbr->priority = hello->priority;
948: nbr->d_router = hello->d_router;
949: nbr->bd_router = hello->bd_router;
950: return;
951: }
952:
953: if (ospf_nbr_bidirectional (&oi->ospf->router_id, hello->neighbors,
954: size - OSPF_HELLO_MIN_SIZE))
955: {
956: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_TwoWayReceived);
957: nbr->options |= hello->options;
958: }
959: else
960: {
961: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_OneWayReceived);
962: /* Set neighbor information. */
963: nbr->priority = hello->priority;
964: nbr->d_router = hello->d_router;
965: nbr->bd_router = hello->bd_router;
966: return;
967: }
968:
969: /* If neighbor itself declares DR and no BDR exists,
970: cause event BackupSeen */
971: if (IPV4_ADDR_SAME (&nbr->address.u.prefix4, &hello->d_router))
972: if (hello->bd_router.s_addr == 0 && oi->state == ISM_Waiting)
973: OSPF_ISM_EVENT_SCHEDULE (oi, ISM_BackupSeen);
974:
975: /* neighbor itself declares BDR. */
976: if (oi->state == ISM_Waiting &&
977: IPV4_ADDR_SAME (&nbr->address.u.prefix4, &hello->bd_router))
978: OSPF_ISM_EVENT_SCHEDULE (oi, ISM_BackupSeen);
979:
980: /* had not previously. */
981: if ((IPV4_ADDR_SAME (&nbr->address.u.prefix4, &hello->d_router) &&
982: IPV4_ADDR_CMP (&nbr->address.u.prefix4, &nbr->d_router)) ||
983: (IPV4_ADDR_CMP (&nbr->address.u.prefix4, &hello->d_router) &&
984: IPV4_ADDR_SAME (&nbr->address.u.prefix4, &nbr->d_router)))
985: OSPF_ISM_EVENT_SCHEDULE (oi, ISM_NeighborChange);
986:
987: /* had not previously. */
988: if ((IPV4_ADDR_SAME (&nbr->address.u.prefix4, &hello->bd_router) &&
989: IPV4_ADDR_CMP (&nbr->address.u.prefix4, &nbr->bd_router)) ||
990: (IPV4_ADDR_CMP (&nbr->address.u.prefix4, &hello->bd_router) &&
991: IPV4_ADDR_SAME (&nbr->address.u.prefix4, &nbr->bd_router)))
992: OSPF_ISM_EVENT_SCHEDULE (oi, ISM_NeighborChange);
993:
994: /* Neighbor priority check. */
995: if (nbr->priority >= 0 && nbr->priority != hello->priority)
996: OSPF_ISM_EVENT_SCHEDULE (oi, ISM_NeighborChange);
997:
998: /* Set neighbor information. */
999: nbr->priority = hello->priority;
1000: nbr->d_router = hello->d_router;
1001: nbr->bd_router = hello->bd_router;
1002: }
1003:
1004: /* Save DD flags/options/Seqnum received. */
1005: static void
1006: ospf_db_desc_save_current (struct ospf_neighbor *nbr,
1007: struct ospf_db_desc *dd)
1008: {
1009: nbr->last_recv.flags = dd->flags;
1010: nbr->last_recv.options = dd->options;
1011: nbr->last_recv.dd_seqnum = ntohl (dd->dd_seqnum);
1012: }
1013:
1014: /* Process rest of DD packet. */
1015: static void
1016: ospf_db_desc_proc (struct stream *s, struct ospf_interface *oi,
1017: struct ospf_neighbor *nbr, struct ospf_db_desc *dd,
1018: u_int16_t size)
1019: {
1020: struct ospf_lsa *new, *find;
1021: struct lsa_header *lsah;
1022:
1023: stream_forward_getp (s, OSPF_DB_DESC_MIN_SIZE);
1024: for (size -= OSPF_DB_DESC_MIN_SIZE;
1025: size >= OSPF_LSA_HEADER_SIZE; size -= OSPF_LSA_HEADER_SIZE)
1026: {
1027: lsah = (struct lsa_header *) STREAM_PNT (s);
1028: stream_forward_getp (s, OSPF_LSA_HEADER_SIZE);
1029:
1030: /* Unknown LS type. */
1031: if (lsah->type < OSPF_MIN_LSA || lsah->type >= OSPF_MAX_LSA)
1032: {
1033: zlog_warn ("Packet [DD:RECV]: Unknown LS type %d.", lsah->type);
1034: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1035: return;
1036: }
1037:
1038: #ifdef HAVE_OPAQUE_LSA
1039: if (IS_OPAQUE_LSA (lsah->type)
1040: && ! CHECK_FLAG (nbr->options, OSPF_OPTION_O))
1041: {
1042: zlog_warn ("LSA[Type%d:%s]: Opaque capability mismatch?", lsah->type, inet_ntoa (lsah->id));
1043: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1044: return;
1045: }
1046: #endif /* HAVE_OPAQUE_LSA */
1047:
1048: switch (lsah->type)
1049: {
1050: case OSPF_AS_EXTERNAL_LSA:
1051: #ifdef HAVE_OPAQUE_LSA
1052: case OSPF_OPAQUE_AS_LSA:
1053: #endif /* HAVE_OPAQUE_LSA */
1054: /* Check for stub area. Reject if AS-External from stub but
1055: allow if from NSSA. */
1056: if (oi->area->external_routing == OSPF_AREA_STUB)
1057: {
1058: zlog_warn ("Packet [DD:RECV]: LSA[Type%d:%s] from %s area.",
1059: lsah->type, inet_ntoa (lsah->id),
1060: (oi->area->external_routing == OSPF_AREA_STUB) ?\
1061: "STUB" : "NSSA");
1062: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1063: return;
1064: }
1065: break;
1066: default:
1067: break;
1068: }
1069:
1070: /* Create LS-request object. */
1071: new = ospf_ls_request_new (lsah);
1072:
1073: /* Lookup received LSA, then add LS request list. */
1074: find = ospf_lsa_lookup_by_header (oi->area, lsah);
1075:
1076: /* ospf_lsa_more_recent is fine with NULL pointers */
1077: switch (ospf_lsa_more_recent (find, new))
1078: {
1079: case -1:
1080: /* Neighbour has a more recent LSA, we must request it */
1081: ospf_ls_request_add (nbr, new);
1082: case 0:
1083: /* If we have a copy of this LSA, it's either less recent
1084: * and we're requesting it from neighbour (the case above), or
1085: * it's as recent and we both have same copy (this case).
1086: *
1087: * In neither of these two cases is there any point in
1088: * describing our copy of the LSA to the neighbour in a
1089: * DB-Summary packet, if we're still intending to do so.
1090: *
1091: * See: draft-ogier-ospf-dbex-opt-00.txt, describing the
1092: * backward compatible optimisation to OSPF DB Exchange /
1093: * DB Description process implemented here.
1094: */
1095: if (find)
1096: ospf_lsdb_delete (&nbr->db_sum, find);
1097: ospf_lsa_discard (new);
1098: break;
1099: default:
1100: /* We have the more recent copy, nothing specific to do:
1101: * - no need to request neighbours stale copy
1102: * - must leave DB summary list copy alone
1103: */
1104: if (IS_DEBUG_OSPF_EVENT)
1105: zlog_debug ("Packet [DD:RECV]: LSA received Type %d, "
1106: "ID %s is not recent.", lsah->type, inet_ntoa (lsah->id));
1107: ospf_lsa_discard (new);
1108: }
1109: }
1110:
1111: /* Master */
1112: if (IS_SET_DD_MS (nbr->dd_flags))
1113: {
1114: nbr->dd_seqnum++;
1115:
1116: /* Both sides have no More, then we're done with Exchange */
1117: if (!IS_SET_DD_M (dd->flags) && !IS_SET_DD_M (nbr->dd_flags))
1118: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_ExchangeDone);
1119: else
1120: ospf_db_desc_send (nbr);
1121: }
1122: /* Slave */
1123: else
1124: {
1125: nbr->dd_seqnum = ntohl (dd->dd_seqnum);
1126:
1127: /* Send DD packet in reply.
1128: *
1129: * Must be done to acknowledge the Master's DD, regardless of
1130: * whether we have more LSAs ourselves to describe.
1131: *
1132: * This function will clear the 'More' bit, if after this DD
1133: * we have no more LSAs to describe to the master..
1134: */
1135: ospf_db_desc_send (nbr);
1136:
1137: /* Slave can raise ExchangeDone now, if master is also done */
1138: if (!IS_SET_DD_M (dd->flags) && !IS_SET_DD_M (nbr->dd_flags))
1139: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_ExchangeDone);
1140: }
1141:
1142: /* Save received neighbor values from DD. */
1143: ospf_db_desc_save_current (nbr, dd);
1144: }
1145:
1146: static int
1147: ospf_db_desc_is_dup (struct ospf_db_desc *dd, struct ospf_neighbor *nbr)
1148: {
1149: /* Is DD duplicated? */
1150: if (dd->options == nbr->last_recv.options &&
1151: dd->flags == nbr->last_recv.flags &&
1152: dd->dd_seqnum == htonl (nbr->last_recv.dd_seqnum))
1153: return 1;
1154:
1155: return 0;
1156: }
1157:
1158: /* OSPF Database Description message read -- RFC2328 Section 10.6. */
1159: static void
1160: ospf_db_desc (struct ip *iph, struct ospf_header *ospfh,
1161: struct stream *s, struct ospf_interface *oi, u_int16_t size)
1162: {
1163: struct ospf_db_desc *dd;
1164: struct ospf_neighbor *nbr;
1165:
1166: /* Increment statistics. */
1167: oi->db_desc_in++;
1168:
1169: dd = (struct ospf_db_desc *) STREAM_PNT (s);
1170:
1171: nbr = ospf_nbr_lookup (oi, iph, ospfh);
1172: if (nbr == NULL)
1173: {
1174: zlog_warn ("Packet[DD]: Unknown Neighbor %s",
1175: inet_ntoa (ospfh->router_id));
1176: return;
1177: }
1178:
1179: /* Check MTU. */
1180: if ((OSPF_IF_PARAM (oi, mtu_ignore) == 0) &&
1181: (ntohs (dd->mtu) > oi->ifp->mtu))
1182: {
1183: zlog_warn ("Packet[DD]: Neighbor %s MTU %u is larger than [%s]'s MTU %u",
1184: inet_ntoa (nbr->router_id), ntohs (dd->mtu),
1185: IF_NAME (oi), oi->ifp->mtu);
1186: return;
1187: }
1188:
1189: /*
1190: * XXX HACK by Hasso Tepper. Setting N/P bit in NSSA area DD packets is not
1191: * required. In fact at least JunOS sends DD packets with P bit clear.
1192: * Until proper solution is developped, this hack should help.
1193: *
1194: * Update: According to the RFCs, N bit is specified /only/ for Hello
1195: * options, unfortunately its use in DD options is not specified. Hence some
1196: * implementations follow E-bit semantics and set it in DD options, and some
1197: * treat it as unspecified and hence follow the directive "default for
1198: * options is clear", ie unset.
1199: *
1200: * Reset the flag, as ospfd follows E-bit semantics.
1201: */
1202: if ( (oi->area->external_routing == OSPF_AREA_NSSA)
1203: && (CHECK_FLAG (nbr->options, OSPF_OPTION_NP))
1204: && (!CHECK_FLAG (dd->options, OSPF_OPTION_NP)) )
1205: {
1206: if (IS_DEBUG_OSPF_EVENT)
1207: zlog_debug ("Packet[DD]: Neighbour %s: Has NSSA capability, sends with N bit clear in DD options",
1208: inet_ntoa (nbr->router_id) );
1209: SET_FLAG (dd->options, OSPF_OPTION_NP);
1210: }
1211:
1212: #ifdef REJECT_IF_TBIT_ON
1213: if (CHECK_FLAG (dd->options, OSPF_OPTION_T))
1214: {
1215: /*
1216: * In Hello protocol, optional capability must have checked
1217: * to prevent this T-bit enabled router be my neighbor.
1218: */
1219: zlog_warn ("Packet[DD]: Neighbor %s: T-bit on?", inet_ntoa (nbr->router_id));
1220: return;
1221: }
1222: #endif /* REJECT_IF_TBIT_ON */
1223:
1224: #ifdef HAVE_OPAQUE_LSA
1225: if (CHECK_FLAG (dd->options, OSPF_OPTION_O)
1226: && !CHECK_FLAG (oi->ospf->config, OSPF_OPAQUE_CAPABLE))
1227: {
1228: /*
1229: * This node is not configured to handle O-bit, for now.
1230: * Clear it to ignore unsupported capability proposed by neighbor.
1231: */
1232: UNSET_FLAG (dd->options, OSPF_OPTION_O);
1233: }
1234: #endif /* HAVE_OPAQUE_LSA */
1235:
1236: /* Add event to thread. */
1237: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_PacketReceived);
1238:
1239: /* Process DD packet by neighbor status. */
1240: switch (nbr->state)
1241: {
1242: case NSM_Down:
1243: case NSM_Attempt:
1244: case NSM_TwoWay:
1245: zlog_warn ("Packet[DD]: Neighbor %s state is %s, packet discarded.",
1246: inet_ntoa(nbr->router_id),
1247: LOOKUP (ospf_nsm_state_msg, nbr->state));
1248: break;
1249: case NSM_Init:
1250: OSPF_NSM_EVENT_EXECUTE (nbr, NSM_TwoWayReceived);
1251: /* If the new state is ExStart, the processing of the current
1252: packet should then continue in this new state by falling
1253: through to case ExStart below. */
1254: if (nbr->state != NSM_ExStart)
1255: break;
1256: case NSM_ExStart:
1257: /* Initial DBD */
1258: if ((IS_SET_DD_ALL (dd->flags) == OSPF_DD_FLAG_ALL) &&
1259: (size == OSPF_DB_DESC_MIN_SIZE))
1260: {
1261: if (IPV4_ADDR_CMP (&nbr->router_id, &oi->ospf->router_id) > 0)
1262: {
1263: /* We're Slave---obey */
1264: zlog_info ("Packet[DD]: Neighbor %s Negotiation done (Slave).",
1265: inet_ntoa(nbr->router_id));
1266: nbr->dd_seqnum = ntohl (dd->dd_seqnum);
1267:
1268: /* Reset I/MS */
1269: UNSET_FLAG (nbr->dd_flags, (OSPF_DD_FLAG_MS|OSPF_DD_FLAG_I));
1270: }
1271: else
1272: {
1273: /* We're Master, ignore the initial DBD from Slave */
1274: zlog_info ("Packet[DD]: Neighbor %s: Initial DBD from Slave, "
1275: "ignoring.", inet_ntoa(nbr->router_id));
1276: break;
1277: }
1278: }
1279: /* Ack from the Slave */
1280: else if (!IS_SET_DD_MS (dd->flags) && !IS_SET_DD_I (dd->flags) &&
1281: ntohl (dd->dd_seqnum) == nbr->dd_seqnum &&
1282: IPV4_ADDR_CMP (&nbr->router_id, &oi->ospf->router_id) < 0)
1283: {
1284: zlog_info ("Packet[DD]: Neighbor %s Negotiation done (Master).",
1285: inet_ntoa(nbr->router_id));
1286: /* Reset I, leaving MS */
1287: UNSET_FLAG (nbr->dd_flags, OSPF_DD_FLAG_I);
1288: }
1289: else
1290: {
1291: zlog_warn ("Packet[DD]: Neighbor %s Negotiation fails.",
1292: inet_ntoa(nbr->router_id));
1293: break;
1294: }
1295:
1296: /* This is where the real Options are saved */
1297: nbr->options = dd->options;
1298:
1299: #ifdef HAVE_OPAQUE_LSA
1300: if (CHECK_FLAG (oi->ospf->config, OSPF_OPAQUE_CAPABLE))
1301: {
1302: if (IS_DEBUG_OSPF_EVENT)
1303: zlog_debug ("Neighbor[%s] is %sOpaque-capable.",
1304: inet_ntoa (nbr->router_id),
1305: CHECK_FLAG (nbr->options, OSPF_OPTION_O) ? "" : "NOT ");
1306:
1307: if (! CHECK_FLAG (nbr->options, OSPF_OPTION_O)
1308: && IPV4_ADDR_SAME (&DR (oi), &nbr->address.u.prefix4))
1309: {
1310: zlog_warn ("DR-neighbor[%s] is NOT opaque-capable; "
1311: "Opaque-LSAs cannot be reliably advertised "
1312: "in this network.",
1313: inet_ntoa (nbr->router_id));
1314: /* This situation is undesirable, but not a real error. */
1315: }
1316: }
1317: #endif /* HAVE_OPAQUE_LSA */
1318:
1319: OSPF_NSM_EVENT_EXECUTE (nbr, NSM_NegotiationDone);
1320:
1321: /* continue processing rest of packet. */
1322: ospf_db_desc_proc (s, oi, nbr, dd, size);
1323: break;
1324: case NSM_Exchange:
1325: if (ospf_db_desc_is_dup (dd, nbr))
1326: {
1327: if (IS_SET_DD_MS (nbr->dd_flags))
1328: /* Master: discard duplicated DD packet. */
1329: zlog_info ("Packet[DD] (Master): Neighbor %s packet duplicated.",
1330: inet_ntoa (nbr->router_id));
1331: else
1332: /* Slave: cause to retransmit the last Database Description. */
1333: {
1334: zlog_info ("Packet[DD] [Slave]: Neighbor %s packet duplicated.",
1335: inet_ntoa (nbr->router_id));
1336: ospf_db_desc_resend (nbr);
1337: }
1338: break;
1339: }
1340:
1341: /* Otherwise DD packet should be checked. */
1342: /* Check Master/Slave bit mismatch */
1343: if (IS_SET_DD_MS (dd->flags) != IS_SET_DD_MS (nbr->last_recv.flags))
1344: {
1345: zlog_warn ("Packet[DD]: Neighbor %s MS-bit mismatch.",
1346: inet_ntoa(nbr->router_id));
1347: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1348: if (IS_DEBUG_OSPF_EVENT)
1349: zlog_debug ("Packet[DD]: dd->flags=%d, nbr->dd_flags=%d",
1350: dd->flags, nbr->dd_flags);
1351: break;
1352: }
1353:
1354: /* Check initialize bit is set. */
1355: if (IS_SET_DD_I (dd->flags))
1356: {
1357: zlog_info ("Packet[DD]: Neighbor %s I-bit set.",
1358: inet_ntoa(nbr->router_id));
1359: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1360: break;
1361: }
1362:
1363: /* Check DD Options. */
1364: if (dd->options != nbr->options)
1365: {
1366: #ifdef ORIGINAL_CODING
1367: /* Save the new options for debugging */
1368: nbr->options = dd->options;
1369: #endif /* ORIGINAL_CODING */
1370: zlog_warn ("Packet[DD]: Neighbor %s options mismatch.",
1371: inet_ntoa(nbr->router_id));
1372: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1373: break;
1374: }
1375:
1376: /* Check DD sequence number. */
1377: if ((IS_SET_DD_MS (nbr->dd_flags) &&
1378: ntohl (dd->dd_seqnum) != nbr->dd_seqnum) ||
1379: (!IS_SET_DD_MS (nbr->dd_flags) &&
1380: ntohl (dd->dd_seqnum) != nbr->dd_seqnum + 1))
1381: {
1382: zlog_warn ("Packet[DD]: Neighbor %s sequence number mismatch.",
1383: inet_ntoa(nbr->router_id));
1384: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1385: break;
1386: }
1387:
1388: /* Continue processing rest of packet. */
1389: ospf_db_desc_proc (s, oi, nbr, dd, size);
1390: break;
1391: case NSM_Loading:
1392: case NSM_Full:
1393: if (ospf_db_desc_is_dup (dd, nbr))
1394: {
1395: if (IS_SET_DD_MS (nbr->dd_flags))
1396: {
1397: /* Master should discard duplicate DD packet. */
1398: zlog_info ("Packet[DD]: Neighbor %s duplicated, "
1399: "packet discarded.",
1400: inet_ntoa(nbr->router_id));
1401: break;
1402: }
1403: else
1404: {
1405: struct timeval t, now;
1406: quagga_gettime (QUAGGA_CLK_MONOTONIC, &now);
1407: t = tv_sub (now, nbr->last_send_ts);
1408: if (tv_cmp (t, int2tv (nbr->v_inactivity)) < 0)
1409: {
1410: /* In states Loading and Full the slave must resend
1411: its last Database Description packet in response to
1412: duplicate Database Description packets received
1413: from the master. For this reason the slave must
1414: wait RouterDeadInterval seconds before freeing the
1415: last Database Description packet. Reception of a
1416: Database Description packet from the master after
1417: this interval will generate a SeqNumberMismatch
1418: neighbor event. RFC2328 Section 10.8 */
1419: ospf_db_desc_resend (nbr);
1420: break;
1421: }
1422: }
1423: }
1424:
1425: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_SeqNumberMismatch);
1426: break;
1427: default:
1428: zlog_warn ("Packet[DD]: Neighbor %s NSM illegal status %u.",
1429: inet_ntoa(nbr->router_id), nbr->state);
1430: break;
1431: }
1432: }
1433:
1434: #define OSPF_LSA_KEY_SIZE 12 /* type(4) + id(4) + ar(4) */
1435:
1436: /* OSPF Link State Request Read -- RFC2328 Section 10.7. */
1437: static void
1438: ospf_ls_req (struct ip *iph, struct ospf_header *ospfh,
1439: struct stream *s, struct ospf_interface *oi, u_int16_t size)
1440: {
1441: struct ospf_neighbor *nbr;
1442: u_int32_t ls_type;
1443: struct in_addr ls_id;
1444: struct in_addr adv_router;
1445: struct ospf_lsa *find;
1446: struct list *ls_upd;
1447: unsigned int length;
1448:
1449: /* Increment statistics. */
1450: oi->ls_req_in++;
1451:
1452: nbr = ospf_nbr_lookup (oi, iph, ospfh);
1453: if (nbr == NULL)
1454: {
1455: zlog_warn ("Link State Request: Unknown Neighbor %s.",
1456: inet_ntoa (ospfh->router_id));
1457: return;
1458: }
1459:
1460: /* Add event to thread. */
1461: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_PacketReceived);
1462:
1463: /* Neighbor State should be Exchange or later. */
1464: if (nbr->state != NSM_Exchange &&
1465: nbr->state != NSM_Loading &&
1466: nbr->state != NSM_Full)
1467: {
1468: zlog_warn ("Link State Request received from %s: "
1469: "Neighbor state is %s, packet discarded.",
1470: inet_ntoa (ospfh->router_id),
1471: LOOKUP (ospf_nsm_state_msg, nbr->state));
1472: return;
1473: }
1474:
1475: /* Send Link State Update for ALL requested LSAs. */
1476: ls_upd = list_new ();
1477: length = OSPF_HEADER_SIZE + OSPF_LS_UPD_MIN_SIZE;
1478:
1479: while (size >= OSPF_LSA_KEY_SIZE)
1480: {
1481: /* Get one slice of Link State Request. */
1482: ls_type = stream_getl (s);
1483: ls_id.s_addr = stream_get_ipv4 (s);
1484: adv_router.s_addr = stream_get_ipv4 (s);
1485:
1486: /* Verify LSA type. */
1487: if (ls_type < OSPF_MIN_LSA || ls_type >= OSPF_MAX_LSA)
1488: {
1489: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_BadLSReq);
1490: list_delete (ls_upd);
1491: return;
1492: }
1493:
1494: /* Search proper LSA in LSDB. */
1495: find = ospf_lsa_lookup (oi->area, ls_type, ls_id, adv_router);
1496: if (find == NULL)
1497: {
1498: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_BadLSReq);
1499: list_delete (ls_upd);
1500: return;
1501: }
1502:
1503: /* Packet overflows MTU size, send immediately. */
1504: if (length + ntohs (find->data->length) > ospf_packet_max (oi))
1505: {
1506: if (oi->type == OSPF_IFTYPE_NBMA)
1507: ospf_ls_upd_send (nbr, ls_upd, OSPF_SEND_PACKET_DIRECT);
1508: else
1509: ospf_ls_upd_send (nbr, ls_upd, OSPF_SEND_PACKET_INDIRECT);
1510:
1511: /* Only remove list contents. Keep ls_upd. */
1512: list_delete_all_node (ls_upd);
1513:
1514: length = OSPF_HEADER_SIZE + OSPF_LS_UPD_MIN_SIZE;
1515: }
1516:
1517: /* Append LSA to update list. */
1518: listnode_add (ls_upd, find);
1519: length += ntohs (find->data->length);
1520:
1521: size -= OSPF_LSA_KEY_SIZE;
1522: }
1523:
1524: /* Send rest of Link State Update. */
1525: if (listcount (ls_upd) > 0)
1526: {
1527: if (oi->type == OSPF_IFTYPE_NBMA)
1528: ospf_ls_upd_send (nbr, ls_upd, OSPF_SEND_PACKET_DIRECT);
1529: else
1530: ospf_ls_upd_send (nbr, ls_upd, OSPF_SEND_PACKET_INDIRECT);
1531:
1532: list_delete (ls_upd);
1533: }
1534: else
1535: list_free (ls_upd);
1536: }
1537:
1538: /* Get the list of LSAs from Link State Update packet.
1539: And process some validation -- RFC2328 Section 13. (1)-(2). */
1540: static struct list *
1541: ospf_ls_upd_list_lsa (struct ospf_neighbor *nbr, struct stream *s,
1542: struct ospf_interface *oi, size_t size)
1543: {
1544: u_int16_t count, sum;
1545: u_int32_t length;
1546: struct lsa_header *lsah;
1547: struct ospf_lsa *lsa;
1548: struct list *lsas;
1549:
1550: lsas = list_new ();
1551:
1552: count = stream_getl (s);
1553: size -= OSPF_LS_UPD_MIN_SIZE; /* # LSAs */
1554:
1555: for (; size >= OSPF_LSA_HEADER_SIZE && count > 0;
1556: size -= length, stream_forward_getp (s, length), count--)
1557: {
1558: lsah = (struct lsa_header *) STREAM_PNT (s);
1559: length = ntohs (lsah->length);
1560:
1561: if (length > size)
1562: {
1563: zlog_warn ("Link State Update: LSA length exceeds packet size.");
1564: break;
1565: }
1566:
1567: /* Validate the LSA's LS checksum. */
1568: sum = lsah->checksum;
1569: if (sum != ospf_lsa_checksum (lsah))
1570: {
1571: zlog_warn ("Link State Update: LSA checksum error %x, %x.",
1572: sum, lsah->checksum);
1573: continue;
1574: }
1575:
1576: /* Examine the LSA's LS type. */
1577: if (lsah->type < OSPF_MIN_LSA || lsah->type >= OSPF_MAX_LSA)
1578: {
1579: zlog_warn ("Link State Update: Unknown LS type %d", lsah->type);
1580: continue;
1581: }
1582:
1583: /*
1584: * What if the received LSA's age is greater than MaxAge?
1585: * Treat it as a MaxAge case -- endo.
1586: */
1587: if (ntohs (lsah->ls_age) > OSPF_LSA_MAXAGE)
1588: lsah->ls_age = htons (OSPF_LSA_MAXAGE);
1589:
1590: #ifdef HAVE_OPAQUE_LSA
1591: if (CHECK_FLAG (nbr->options, OSPF_OPTION_O))
1592: {
1593: #ifdef STRICT_OBIT_USAGE_CHECK
1594: if ((IS_OPAQUE_LSA(lsah->type) &&
1595: ! CHECK_FLAG (lsah->options, OSPF_OPTION_O))
1596: || (! IS_OPAQUE_LSA(lsah->type) &&
1597: CHECK_FLAG (lsah->options, OSPF_OPTION_O)))
1598: {
1599: /*
1600: * This neighbor must know the exact usage of O-bit;
1601: * the bit will be set in Type-9,10,11 LSAs only.
1602: */
1603: zlog_warn ("LSA[Type%d:%s]: O-bit abuse?", lsah->type, inet_ntoa (lsah->id));
1604: continue;
1605: }
1606: #endif /* STRICT_OBIT_USAGE_CHECK */
1607:
1608: /* Do not take in AS External Opaque-LSAs if we are a stub. */
1609: if (lsah->type == OSPF_OPAQUE_AS_LSA
1610: && nbr->oi->area->external_routing != OSPF_AREA_DEFAULT)
1611: {
1612: if (IS_DEBUG_OSPF_EVENT)
1613: zlog_debug ("LSA[Type%d:%s]: We are a stub, don't take this LSA.", lsah->type, inet_ntoa (lsah->id));
1614: continue;
1615: }
1616: }
1617: else if (IS_OPAQUE_LSA(lsah->type))
1618: {
1619: zlog_warn ("LSA[Type%d:%s]: Opaque capability mismatch?", lsah->type, inet_ntoa (lsah->id));
1620: continue;
1621: }
1622: #endif /* HAVE_OPAQUE_LSA */
1623:
1624: /* Create OSPF LSA instance. */
1625: lsa = ospf_lsa_new ();
1626:
1627: /* We may wish to put some error checking if type NSSA comes in
1628: and area not in NSSA mode */
1629: switch (lsah->type)
1630: {
1631: case OSPF_AS_EXTERNAL_LSA:
1632: #ifdef HAVE_OPAQUE_LSA
1633: case OSPF_OPAQUE_AS_LSA:
1634: lsa->area = NULL;
1635: break;
1636: case OSPF_OPAQUE_LINK_LSA:
1637: lsa->oi = oi; /* Remember incoming interface for flooding control. */
1638: /* Fallthrough */
1639: #endif /* HAVE_OPAQUE_LSA */
1640: default:
1641: lsa->area = oi->area;
1642: break;
1643: }
1644:
1645: lsa->data = ospf_lsa_data_new (length);
1646: memcpy (lsa->data, lsah, length);
1647:
1648: if (IS_DEBUG_OSPF_EVENT)
1649: zlog_debug("LSA[Type%d:%s]: %p new LSA created with Link State Update",
1650: lsa->data->type, inet_ntoa (lsa->data->id), lsa);
1651: listnode_add (lsas, lsa);
1652: }
1653:
1654: return lsas;
1655: }
1656:
1657: /* Cleanup Update list. */
1658: static void
1659: ospf_upd_list_clean (struct list *lsas)
1660: {
1661: struct listnode *node, *nnode;
1662: struct ospf_lsa *lsa;
1663:
1664: for (ALL_LIST_ELEMENTS (lsas, node, nnode, lsa))
1665: ospf_lsa_discard (lsa);
1666:
1667: list_delete (lsas);
1668: }
1669:
1670: /* OSPF Link State Update message read -- RFC2328 Section 13. */
1671: static void
1672: ospf_ls_upd (struct ip *iph, struct ospf_header *ospfh,
1673: struct stream *s, struct ospf_interface *oi, u_int16_t size)
1674: {
1675: struct ospf_neighbor *nbr;
1676: struct list *lsas;
1677: struct listnode *node, *nnode;
1678: struct ospf_lsa *lsa = NULL;
1679: /* unsigned long ls_req_found = 0; */
1680:
1681: /* Dis-assemble the stream, update each entry, re-encapsulate for flooding */
1682:
1683: /* Increment statistics. */
1684: oi->ls_upd_in++;
1685:
1686: /* Check neighbor. */
1687: nbr = ospf_nbr_lookup (oi, iph, ospfh);
1688: if (nbr == NULL)
1689: {
1690: zlog_warn ("Link State Update: Unknown Neighbor %s on int: %s",
1691: inet_ntoa (ospfh->router_id), IF_NAME (oi));
1692: return;
1693: }
1694:
1695: /* Add event to thread. */
1696: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_PacketReceived);
1697:
1698: /* Check neighbor state. */
1699: if (nbr->state < NSM_Exchange)
1700: {
1701: zlog_warn ("Link State Update: "
1702: "Neighbor[%s] state %s is less than Exchange",
1703: inet_ntoa (ospfh->router_id),
1704: LOOKUP(ospf_nsm_state_msg, nbr->state));
1705: return;
1706: }
1707:
1708: /* Get list of LSAs from Link State Update packet. - Also perorms Stages
1709: * 1 (validate LSA checksum) and 2 (check for LSA consistent type)
1710: * of section 13.
1711: */
1712: lsas = ospf_ls_upd_list_lsa (nbr, s, oi, size);
1713:
1714: #ifdef HAVE_OPAQUE_LSA
1715: /*
1716: * If self-originated Opaque-LSAs that have flooded before restart
1717: * are contained in the received LSUpd message, corresponding LSReq
1718: * messages to be sent may have to be modified.
1719: * To eliminate possible race conditions such that flushing and normal
1720: * updating for the same LSA would take place alternately, this trick
1721: * must be done before entering to the loop below.
1722: */
1723: /* XXX: Why is this Opaque specific? Either our core code is deficient
1724: * and this should be fixed generally, or Opaque is inventing strawman
1725: * problems */
1726: ospf_opaque_adjust_lsreq (nbr, lsas);
1727: #endif /* HAVE_OPAQUE_LSA */
1728:
1729: #define DISCARD_LSA(L,N) {\
1730: if (IS_DEBUG_OSPF_EVENT) \
1731: zlog_debug ("ospf_lsa_discard() in ospf_ls_upd() point %d: lsa %p Type-%d", N, lsa, (int) lsa->data->type); \
1732: ospf_lsa_discard (L); \
1733: continue; }
1734:
1735: /* Process each LSA received in the one packet. */
1736: for (ALL_LIST_ELEMENTS (lsas, node, nnode, lsa))
1737: {
1738: struct ospf_lsa *ls_ret, *current;
1739: int ret = 1;
1740:
1741: if (IS_DEBUG_OSPF_NSSA)
1742: {
1743: char buf1[INET_ADDRSTRLEN];
1744: char buf2[INET_ADDRSTRLEN];
1745: char buf3[INET_ADDRSTRLEN];
1746:
1747: zlog_debug("LSA Type-%d from %s, ID: %s, ADV: %s",
1748: lsa->data->type,
1749: inet_ntop (AF_INET, &ospfh->router_id,
1750: buf1, INET_ADDRSTRLEN),
1751: inet_ntop (AF_INET, &lsa->data->id,
1752: buf2, INET_ADDRSTRLEN),
1753: inet_ntop (AF_INET, &lsa->data->adv_router,
1754: buf3, INET_ADDRSTRLEN));
1755: }
1756:
1757: listnode_delete (lsas, lsa); /* We don't need it in list anymore */
1758:
1759: /* Validate Checksum - Done above by ospf_ls_upd_list_lsa() */
1760:
1761: /* LSA Type - Done above by ospf_ls_upd_list_lsa() */
1762:
1763: /* Do not take in AS External LSAs if we are a stub or NSSA. */
1764:
1765: /* Do not take in AS NSSA if this neighbor and we are not NSSA */
1766:
1767: /* Do take in Type-7's if we are an NSSA */
1768:
1769: /* If we are also an ABR, later translate them to a Type-5 packet */
1770:
1771: /* Later, an NSSA Re-fresh can Re-fresh Type-7's and an ABR will
1772: translate them to a separate Type-5 packet. */
1773:
1774: if (lsa->data->type == OSPF_AS_EXTERNAL_LSA)
1775: /* Reject from STUB or NSSA */
1776: if (nbr->oi->area->external_routing != OSPF_AREA_DEFAULT)
1777: {
1778: if (IS_DEBUG_OSPF_NSSA)
1779: zlog_debug("Incoming External LSA Discarded: We are NSSA/STUB Area");
1780: DISCARD_LSA (lsa, 1);
1781: }
1782:
1783: if (lsa->data->type == OSPF_AS_NSSA_LSA)
1784: if (nbr->oi->area->external_routing != OSPF_AREA_NSSA)
1785: {
1786: if (IS_DEBUG_OSPF_NSSA)
1787: zlog_debug("Incoming NSSA LSA Discarded: Not NSSA Area");
1788: DISCARD_LSA (lsa,2);
1789: }
1790:
1791: /* Find the LSA in the current database. */
1792:
1793: current = ospf_lsa_lookup_by_header (oi->area, lsa->data);
1794:
1795: /* If the LSA's LS age is equal to MaxAge, and there is currently
1796: no instance of the LSA in the router's link state database,
1797: and none of router's neighbors are in states Exchange or Loading,
1798: then take the following actions. */
1799:
1800: if (IS_LSA_MAXAGE (lsa) && !current &&
1801: (ospf_nbr_count (oi, NSM_Exchange) +
1802: ospf_nbr_count (oi, NSM_Loading)) == 0)
1803: {
1804: /* Response Link State Acknowledgment. */
1805: ospf_ls_ack_send (nbr, lsa);
1806:
1807: /* Discard LSA. */
1808: zlog_info ("Link State Update[%s]: LS age is equal to MaxAge.",
1809: dump_lsa_key(lsa));
1810: DISCARD_LSA (lsa, 3);
1811: }
1812:
1813: #ifdef HAVE_OPAQUE_LSA
1814: if (IS_OPAQUE_LSA (lsa->data->type)
1815: && IPV4_ADDR_SAME (&lsa->data->adv_router, &oi->ospf->router_id))
1816: {
1817: /*
1818: * Even if initial flushing seems to be completed, there might
1819: * be a case that self-originated LSA with MaxAge still remain
1820: * in the routing domain.
1821: * Just send an LSAck message to cease retransmission.
1822: */
1823: if (IS_LSA_MAXAGE (lsa))
1824: {
1825: zlog_warn ("LSA[%s]: Boomerang effect?", dump_lsa_key (lsa));
1826: ospf_ls_ack_send (nbr, lsa);
1827: ospf_lsa_discard (lsa);
1828:
1829: if (current != NULL && ! IS_LSA_MAXAGE (current))
1830: ospf_opaque_lsa_refresh_schedule (current);
1831: continue;
1832: }
1833:
1834: /*
1835: * If an instance of self-originated Opaque-LSA is not found
1836: * in the LSDB, there are some possible cases here.
1837: *
1838: * 1) This node lost opaque-capability after restart.
1839: * 2) Else, a part of opaque-type is no more supported.
1840: * 3) Else, a part of opaque-id is no more supported.
1841: *
1842: * Anyway, it is still this node's responsibility to flush it.
1843: * Otherwise, the LSA instance remains in the routing domain
1844: * until its age reaches to MaxAge.
1845: */
1846: /* XXX: We should deal with this for *ALL* LSAs, not just opaque */
1847: if (current == NULL)
1848: {
1849: if (IS_DEBUG_OSPF_EVENT)
1850: zlog_debug ("LSA[%s]: Previously originated Opaque-LSA,"
1851: "not found in the LSDB.", dump_lsa_key (lsa));
1852:
1853: SET_FLAG (lsa->flags, OSPF_LSA_SELF);
1854:
1855: ospf_opaque_self_originated_lsa_received (nbr, lsa);
1856: ospf_ls_ack_send (nbr, lsa);
1857:
1858: continue;
1859: }
1860: }
1861: #endif /* HAVE_OPAQUE_LSA */
1862:
1863: /* It might be happen that received LSA is self-originated network LSA, but
1864: * router ID is cahnged. So, we should check if LSA is a network-LSA whose
1865: * Link State ID is one of the router's own IP interface addresses but whose
1866: * Advertising Router is not equal to the router's own Router ID
1867: * According to RFC 2328 12.4.2 and 13.4 this LSA should be flushed.
1868: */
1869:
1870: if(lsa->data->type == OSPF_NETWORK_LSA)
1871: {
1872: struct listnode *oinode, *oinnode;
1873: struct ospf_interface *out_if;
1874: int Flag = 0;
1875:
1876: for (ALL_LIST_ELEMENTS (oi->ospf->oiflist, oinode, oinnode, out_if))
1877: {
1878: if(out_if == NULL)
1879: break;
1880:
1881: if((IPV4_ADDR_SAME(&out_if->address->u.prefix4, &lsa->data->id)) &&
1882: (!(IPV4_ADDR_SAME(&oi->ospf->router_id, &lsa->data->adv_router))))
1883: {
1884: if(out_if->network_lsa_self)
1885: {
1886: ospf_lsa_flush_area(lsa,out_if->area);
1887: if(IS_DEBUG_OSPF_EVENT)
1888: zlog_debug ("ospf_lsa_discard() in ospf_ls_upd() point 9: lsa %p Type-%d",
1889: lsa, (int) lsa->data->type);
1890: ospf_lsa_discard (lsa);
1891: Flag = 1;
1892: }
1893: break;
1894: }
1895: }
1896: if(Flag)
1897: continue;
1898: }
1899:
1900: /* (5) Find the instance of this LSA that is currently contained
1901: in the router's link state database. If there is no
1902: database copy, or the received LSA is more recent than
1903: the database copy the following steps must be performed. */
1904:
1905: if (current == NULL ||
1906: (ret = ospf_lsa_more_recent (current, lsa)) < 0)
1907: {
1908: /* Actual flooding procedure. */
1909: if (ospf_flood (oi->ospf, nbr, current, lsa) < 0) /* Trap NSSA later. */
1910: DISCARD_LSA (lsa, 4);
1911: continue;
1912: }
1913:
1914: /* (6) Else, If there is an instance of the LSA on the sending
1915: neighbor's Link state request list, an error has occurred in
1916: the Database Exchange process. In this case, restart the
1917: Database Exchange process by generating the neighbor event
1918: BadLSReq for the sending neighbor and stop processing the
1919: Link State Update packet. */
1920:
1921: if (ospf_ls_request_lookup (nbr, lsa))
1922: {
1923: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_BadLSReq);
1924: zlog_warn("LSA[%s] instance exists on Link state request list",
1925: dump_lsa_key(lsa));
1926:
1927: /* Clean list of LSAs. */
1928: ospf_upd_list_clean (lsas);
1929: /* this lsa is not on lsas list already. */
1930: ospf_lsa_discard (lsa);
1931: return;
1932: }
1933:
1934: /* If the received LSA is the same instance as the database copy
1935: (i.e., neither one is more recent) the following two steps
1936: should be performed: */
1937:
1938: if (ret == 0)
1939: {
1940: /* If the LSA is listed in the Link state retransmission list
1941: for the receiving adjacency, the router itself is expecting
1942: an acknowledgment for this LSA. The router should treat the
1943: received LSA as an acknowledgment by removing the LSA from
1944: the Link state retransmission list. This is termed an
1945: "implied acknowledgment". */
1946:
1947: ls_ret = ospf_ls_retransmit_lookup (nbr, lsa);
1948:
1949: if (ls_ret != NULL)
1950: {
1951: ospf_ls_retransmit_delete (nbr, ls_ret);
1952:
1953: /* Delayed acknowledgment sent if advertisement received
1954: from Designated Router, otherwise do nothing. */
1955: if (oi->state == ISM_Backup)
1956: if (NBR_IS_DR (nbr))
1957: listnode_add (oi->ls_ack, ospf_lsa_lock (lsa));
1958:
1959: DISCARD_LSA (lsa, 5);
1960: }
1961: else
1962: /* Acknowledge the receipt of the LSA by sending a
1963: Link State Acknowledgment packet back out the receiving
1964: interface. */
1965: {
1966: ospf_ls_ack_send (nbr, lsa);
1967: DISCARD_LSA (lsa, 6);
1968: }
1969: }
1970:
1971: /* The database copy is more recent. If the database copy
1972: has LS age equal to MaxAge and LS sequence number equal to
1973: MaxSequenceNumber, simply discard the received LSA without
1974: acknowledging it. (In this case, the LSA's LS sequence number is
1975: wrapping, and the MaxSequenceNumber LSA must be completely
1976: flushed before any new LSA instance can be introduced). */
1977:
1978: else if (ret > 0) /* Database copy is more recent */
1979: {
1980: if (IS_LSA_MAXAGE (current) &&
1981: current->data->ls_seqnum == htonl (OSPF_MAX_SEQUENCE_NUMBER))
1982: {
1983: DISCARD_LSA (lsa, 7);
1984: }
1985: /* Otherwise, as long as the database copy has not been sent in a
1986: Link State Update within the last MinLSArrival seconds, send the
1987: database copy back to the sending neighbor, encapsulated within
1988: a Link State Update Packet. The Link State Update Packet should
1989: be sent directly to the neighbor. In so doing, do not put the
1990: database copy of the LSA on the neighbor's link state
1991: retransmission list, and do not acknowledge the received (less
1992: recent) LSA instance. */
1993: else
1994: {
1995: struct timeval now;
1996:
1997: quagga_gettime (QUAGGA_CLK_MONOTONIC, &now);
1998:
1999: if (tv_cmp (tv_sub (now, current->tv_orig),
2000: int2tv (OSPF_MIN_LS_ARRIVAL)) >= 0)
2001: /* Trap NSSA type later.*/
2002: ospf_ls_upd_send_lsa (nbr, current, OSPF_SEND_PACKET_DIRECT);
2003: DISCARD_LSA (lsa, 8);
2004: }
2005: }
2006: }
2007: #undef DISCARD_LSA
2008:
2009: assert (listcount (lsas) == 0);
2010: list_delete (lsas);
2011: }
2012:
2013: /* OSPF Link State Acknowledgment message read -- RFC2328 Section 13.7. */
2014: static void
2015: ospf_ls_ack (struct ip *iph, struct ospf_header *ospfh,
2016: struct stream *s, struct ospf_interface *oi, u_int16_t size)
2017: {
2018: struct ospf_neighbor *nbr;
2019:
2020: /* increment statistics. */
2021: oi->ls_ack_in++;
2022:
2023: nbr = ospf_nbr_lookup (oi, iph, ospfh);
2024: if (nbr == NULL)
2025: {
2026: zlog_warn ("Link State Acknowledgment: Unknown Neighbor %s.",
2027: inet_ntoa (ospfh->router_id));
2028: return;
2029: }
2030:
2031: /* Add event to thread. */
2032: OSPF_NSM_EVENT_SCHEDULE (nbr, NSM_PacketReceived);
2033:
2034: if (nbr->state < NSM_Exchange)
2035: {
2036: zlog_warn ("Link State Acknowledgment: "
2037: "Neighbor[%s] state %s is less than Exchange",
2038: inet_ntoa (ospfh->router_id),
2039: LOOKUP(ospf_nsm_state_msg, nbr->state));
2040: return;
2041: }
2042:
2043: while (size >= OSPF_LSA_HEADER_SIZE)
2044: {
2045: struct ospf_lsa *lsa, *lsr;
2046:
2047: lsa = ospf_lsa_new ();
2048: lsa->data = (struct lsa_header *) STREAM_PNT (s);
2049:
2050: /* lsah = (struct lsa_header *) STREAM_PNT (s); */
2051: size -= OSPF_LSA_HEADER_SIZE;
2052: stream_forward_getp (s, OSPF_LSA_HEADER_SIZE);
2053:
2054: if (lsa->data->type < OSPF_MIN_LSA || lsa->data->type >= OSPF_MAX_LSA)
2055: {
2056: lsa->data = NULL;
2057: ospf_lsa_discard (lsa);
2058: continue;
2059: }
2060:
2061: lsr = ospf_ls_retransmit_lookup (nbr, lsa);
2062:
2063: if (lsr != NULL && lsr->data->ls_seqnum == lsa->data->ls_seqnum)
2064: {
2065: #ifdef HAVE_OPAQUE_LSA
2066: if (IS_OPAQUE_LSA (lsr->data->type))
2067: ospf_opaque_ls_ack_received (nbr, lsr);
2068: #endif /* HAVE_OPAQUE_LSA */
2069:
2070: ospf_ls_retransmit_delete (nbr, lsr);
2071: }
2072:
2073: lsa->data = NULL;
2074: ospf_lsa_discard (lsa);
2075: }
2076:
2077: return;
2078: }
2079:
2080: static struct stream *
2081: ospf_recv_packet (int fd, struct interface **ifp, struct stream *ibuf)
2082: {
2083: int ret;
2084: struct ip *iph;
2085: u_int16_t ip_len;
2086: unsigned int ifindex = 0;
2087: struct iovec iov;
2088: /* Header and data both require alignment. */
2089: char buff [CMSG_SPACE(SOPT_SIZE_CMSG_IFINDEX_IPV4())];
2090: struct msghdr msgh;
2091:
2092: memset (&msgh, 0, sizeof (struct msghdr));
2093: msgh.msg_iov = &iov;
2094: msgh.msg_iovlen = 1;
2095: msgh.msg_control = (caddr_t) buff;
2096: msgh.msg_controllen = sizeof (buff);
2097:
2098: ret = stream_recvmsg (ibuf, fd, &msgh, 0, OSPF_MAX_PACKET_SIZE+1);
2099: if (ret < 0)
2100: {
2101: zlog_warn("stream_recvmsg failed: %s", safe_strerror(errno));
2102: return NULL;
2103: }
2104: if ((unsigned int)ret < sizeof(iph)) /* ret must be > 0 now */
2105: {
2106: zlog_warn("ospf_recv_packet: discarding runt packet of length %d "
2107: "(ip header size is %u)",
2108: ret, (u_int)sizeof(iph));
2109: return NULL;
2110: }
2111:
2112: /* Note that there should not be alignment problems with this assignment
2113: because this is at the beginning of the stream data buffer. */
2114: iph = (struct ip *) STREAM_DATA(ibuf);
2115: sockopt_iphdrincl_swab_systoh (iph);
2116:
2117: ip_len = iph->ip_len;
2118:
2119: #if !defined(GNU_LINUX) && (OpenBSD < 200311)
2120: /*
2121: * Kernel network code touches incoming IP header parameters,
2122: * before protocol specific processing.
2123: *
2124: * 1) Convert byteorder to host representation.
2125: * --> ip_len, ip_id, ip_off
2126: *
2127: * 2) Adjust ip_len to strip IP header size!
2128: * --> If user process receives entire IP packet via RAW
2129: * socket, it must consider adding IP header size to
2130: * the "ip_len" field of "ip" structure.
2131: *
2132: * For more details, see <netinet/ip_input.c>.
2133: */
2134: ip_len = ip_len + (iph->ip_hl << 2);
2135: #endif
2136:
2137: #if defined(__DragonFly__)
2138: /*
2139: * in DragonFly's raw socket, ip_len/ip_off are read
2140: * in network byte order.
2141: * As OpenBSD < 200311 adjust ip_len to strip IP header size!
2142: */
2143: ip_len = ntohs(iph->ip_len) + (iph->ip_hl << 2);
2144: #endif
2145:
2146: ifindex = getsockopt_ifindex (AF_INET, &msgh);
2147:
2148: *ifp = if_lookup_by_index (ifindex);
2149:
2150: if (ret != ip_len)
2151: {
2152: zlog_warn ("ospf_recv_packet read length mismatch: ip_len is %d, "
2153: "but recvmsg returned %d", ip_len, ret);
2154: return NULL;
2155: }
2156:
2157: return ibuf;
2158: }
2159:
2160: static struct ospf_interface *
2161: ospf_associate_packet_vl (struct ospf *ospf, struct interface *ifp,
2162: struct ip *iph, struct ospf_header *ospfh)
2163: {
2164: struct ospf_interface *rcv_oi;
2165: struct ospf_vl_data *vl_data;
2166: struct ospf_area *vl_area;
2167: struct listnode *node;
2168:
2169: if (IN_MULTICAST (ntohl (iph->ip_dst.s_addr)) ||
2170: !OSPF_IS_AREA_BACKBONE (ospfh))
2171: return NULL;
2172:
2173: /* look for local OSPF interface matching the destination
2174: * to determine Area ID. We presume therefore the destination address
2175: * is unique, or at least (for "unnumbered" links), not used in other
2176: * areas
2177: */
2178: if ((rcv_oi = ospf_if_lookup_by_local_addr (ospf, NULL,
2179: iph->ip_dst)) == NULL)
2180: return NULL;
2181:
2182: for (ALL_LIST_ELEMENTS_RO (ospf->vlinks, node, vl_data))
2183: {
2184: vl_area = ospf_area_lookup_by_area_id (ospf, vl_data->vl_area_id);
2185: if (!vl_area)
2186: continue;
2187:
2188: if (OSPF_AREA_SAME (&vl_area, &rcv_oi->area) &&
2189: IPV4_ADDR_SAME (&vl_data->vl_peer, &ospfh->router_id))
2190: {
2191: if (IS_DEBUG_OSPF_EVENT)
2192: zlog_debug ("associating packet with %s",
2193: IF_NAME (vl_data->vl_oi));
2194: if (! CHECK_FLAG (vl_data->vl_oi->ifp->flags, IFF_UP))
2195: {
2196: if (IS_DEBUG_OSPF_EVENT)
2197: zlog_debug ("This VL is not up yet, sorry");
2198: return NULL;
2199: }
2200:
2201: return vl_data->vl_oi;
2202: }
2203: }
2204:
2205: if (IS_DEBUG_OSPF_EVENT)
2206: zlog_debug ("couldn't find any VL to associate the packet with");
2207:
2208: return NULL;
2209: }
2210:
2211: static inline int
2212: ospf_check_area_id (struct ospf_interface *oi, struct ospf_header *ospfh)
2213: {
2214: /* Check match the Area ID of the receiving interface. */
2215: if (OSPF_AREA_SAME (&oi->area, &ospfh))
2216: return 1;
2217:
2218: return 0;
2219: }
2220:
2221: /* Unbound socket will accept any Raw IP packets if proto is matched.
2222: To prevent it, compare src IP address and i/f address with masking
2223: i/f network mask. */
2224: static int
2225: ospf_check_network_mask (struct ospf_interface *oi, struct in_addr ip_src)
2226: {
2227: struct in_addr mask, me, him;
2228:
2229: if (oi->type == OSPF_IFTYPE_POINTOPOINT ||
2230: oi->type == OSPF_IFTYPE_VIRTUALLINK)
2231: return 1;
2232:
2233: masklen2ip (oi->address->prefixlen, &mask);
2234:
2235: me.s_addr = oi->address->u.prefix4.s_addr & mask.s_addr;
2236: him.s_addr = ip_src.s_addr & mask.s_addr;
2237:
2238: if (IPV4_ADDR_SAME (&me, &him))
2239: return 1;
2240:
2241: return 0;
2242: }
2243:
2244: static int
2245: ospf_check_auth (struct ospf_interface *oi, struct stream *ibuf,
2246: struct ospf_header *ospfh)
2247: {
2248: int ret = 0;
2249: struct crypt_key *ck;
2250:
2251: switch (ntohs (ospfh->auth_type))
2252: {
2253: case OSPF_AUTH_NULL:
2254: ret = 1;
2255: break;
2256: case OSPF_AUTH_SIMPLE:
2257: if (!memcmp (OSPF_IF_PARAM (oi, auth_simple), ospfh->u.auth_data, OSPF_AUTH_SIMPLE_SIZE))
2258: ret = 1;
2259: else
2260: ret = 0;
2261: break;
2262: case OSPF_AUTH_CRYPTOGRAPHIC:
2263: if ((ck = listgetdata (listtail(OSPF_IF_PARAM (oi,auth_crypt)))) == NULL)
2264: {
2265: ret = 0;
2266: break;
2267: }
2268:
2269: /* This is very basic, the digest processing is elsewhere */
2270: if (ospfh->u.crypt.auth_data_len == OSPF_AUTH_MD5_SIZE &&
2271: ospfh->u.crypt.key_id == ck->key_id &&
2272: ntohs (ospfh->length) + OSPF_AUTH_SIMPLE_SIZE <= stream_get_size (ibuf))
2273: ret = 1;
2274: else
2275: ret = 0;
2276: break;
2277: default:
2278: ret = 0;
2279: break;
2280: }
2281:
2282: return ret;
2283: }
2284:
2285: static int
2286: ospf_check_sum (struct ospf_header *ospfh)
2287: {
2288: u_int32_t ret;
2289: u_int16_t sum;
2290:
2291: /* clear auth_data for checksum. */
2292: memset (ospfh->u.auth_data, 0, OSPF_AUTH_SIMPLE_SIZE);
2293:
2294: /* keep checksum and clear. */
2295: sum = ospfh->checksum;
2296: memset (&ospfh->checksum, 0, sizeof (u_int16_t));
2297:
2298: /* calculate checksum. */
2299: ret = in_cksum (ospfh, ntohs (ospfh->length));
2300:
2301: if (ret != sum)
2302: {
2303: zlog_info ("ospf_check_sum(): checksum mismatch, my %X, his %X",
2304: ret, sum);
2305: return 0;
2306: }
2307:
2308: return 1;
2309: }
2310:
2311: /* OSPF Header verification. */
2312: static int
2313: ospf_verify_header (struct stream *ibuf, struct ospf_interface *oi,
2314: struct ip *iph, struct ospf_header *ospfh)
2315: {
2316: /* check version. */
2317: if (ospfh->version != OSPF_VERSION)
2318: {
2319: zlog_warn ("interface %s: ospf_read version number mismatch.",
2320: IF_NAME (oi));
2321: return -1;
2322: }
2323:
2324: /* Valid OSPFv2 packet types are 1 through 5 inclusive. */
2325: if (ospfh->type < 1 || ospfh->type > 5)
2326: {
2327: zlog_warn ("interface %s: invalid packet type %u", IF_NAME (oi), ospfh->type);
2328: return -1;
2329: }
2330:
2331: /* Check Area ID. */
2332: if (!ospf_check_area_id (oi, ospfh))
2333: {
2334: zlog_warn ("interface %s: ospf_read invalid Area ID %s.",
2335: IF_NAME (oi), inet_ntoa (ospfh->area_id));
2336: return -1;
2337: }
2338:
2339: /* Check network mask, Silently discarded. */
2340: if (! ospf_check_network_mask (oi, iph->ip_src))
2341: {
2342: zlog_warn ("interface %s: ospf_read network address is not same [%s]",
2343: IF_NAME (oi), inet_ntoa (iph->ip_src));
2344: return -1;
2345: }
2346:
2347: /* Check authentication. */
2348: if (ospf_auth_type (oi) != ntohs (ospfh->auth_type))
2349: {
2350: zlog_warn ("interface %s: auth-type mismatch, local %d, rcvd %d",
2351: IF_NAME (oi), ospf_auth_type (oi), ntohs (ospfh->auth_type));
2352: return -1;
2353: }
2354:
2355: if (! ospf_check_auth (oi, ibuf, ospfh))
2356: {
2357: zlog_warn ("interface %s: ospf_read authentication failed.",
2358: IF_NAME (oi));
2359: return -1;
2360: }
2361:
2362: /* if check sum is invalid, packet is discarded. */
2363: if (ntohs (ospfh->auth_type) != OSPF_AUTH_CRYPTOGRAPHIC)
2364: {
2365: if (! ospf_check_sum (ospfh))
2366: {
2367: zlog_warn ("interface %s: ospf_read packet checksum error %s",
2368: IF_NAME (oi), inet_ntoa (ospfh->router_id));
2369: return -1;
2370: }
2371: }
2372: else
2373: {
2374: if (ospfh->checksum != 0)
2375: return -1;
2376: if (ospf_check_md5_digest (oi, ibuf, ntohs (ospfh->length)) == 0)
2377: {
2378: zlog_warn ("interface %s: ospf_read md5 authentication failed.",
2379: IF_NAME (oi));
2380: return -1;
2381: }
2382: }
2383:
2384: return 0;
2385: }
2386:
2387: /* Starting point of packet process function. */
2388: int
2389: ospf_read (struct thread *thread)
2390: {
2391: int ret;
2392: struct stream *ibuf;
2393: struct ospf *ospf;
2394: struct ospf_interface *oi;
2395: struct ip *iph;
2396: struct ospf_header *ospfh;
2397: u_int16_t length;
2398: struct interface *ifp;
2399:
2400: /* first of all get interface pointer. */
2401: ospf = THREAD_ARG (thread);
2402:
2403: /* prepare for next packet. */
2404: ospf->t_read = thread_add_read (master, ospf_read, ospf, ospf->fd);
2405:
2406: /* read OSPF packet. */
2407: stream_reset(ospf->ibuf);
2408: if (!(ibuf = ospf_recv_packet (ospf->fd, &ifp, ospf->ibuf)))
2409: return -1;
2410:
2411: /* Note that there should not be alignment problems with this assignment
2412: because this is at the beginning of the stream data buffer. */
2413: iph = (struct ip *) STREAM_DATA (ibuf);
2414: /* Note that sockopt_iphdrincl_swab_systoh was called in ospf_recv_packet. */
2415:
2416: if (ifp == NULL)
2417: /* Handle cases where the platform does not support retrieving the ifindex,
2418: and also platforms (such as Solaris 8) that claim to support ifindex
2419: retrieval but do not. */
2420: ifp = if_lookup_address (iph->ip_src);
2421:
2422: if (ifp == NULL)
2423: return 0;
2424:
2425: /* IP Header dump. */
2426: if (IS_DEBUG_OSPF_PACKET(0, RECV))
2427: ospf_ip_header_dump (iph);
2428:
2429: /* Self-originated packet should be discarded silently. */
2430: if (ospf_if_lookup_by_local_addr (ospf, NULL, iph->ip_src))
2431: {
2432: if (IS_DEBUG_OSPF_PACKET (0, RECV))
2433: {
2434: zlog_debug ("ospf_read[%s]: Dropping self-originated packet",
2435: inet_ntoa (iph->ip_src));
2436: }
2437: return 0;
2438: }
2439:
2440: /* Advance from IP header to OSPF header (iph->ip_hl has been verified
2441: by ospf_recv_packet() to be correct). */
2442: stream_forward_getp (ibuf, iph->ip_hl * 4);
2443:
2444: /* Make sure the OSPF header is really there. */
2445: if (stream_get_endp (ibuf) - stream_get_getp (ibuf) < OSPF_HEADER_SIZE)
2446: {
2447: zlog_debug ("ospf_read: ignored OSPF packet with undersized (%u bytes) header",
2448: stream_get_endp (ibuf) - stream_get_getp (ibuf));
2449: return -1;
2450: }
2451:
2452: /* Now it is safe to access all fields of OSPF packet header. */
2453: ospfh = (struct ospf_header *) STREAM_PNT (ibuf);
2454:
2455: /* associate packet with ospf interface */
2456: oi = ospf_if_lookup_recv_if (ospf, iph->ip_src, ifp);
2457:
2458: /* ospf_verify_header() relies on a valid "oi" and thus can be called only
2459: after the passive/backbone/other checks below are passed. These checks
2460: in turn access the fields of unverified "ospfh" structure for their own
2461: purposes and must remain very accurate in doing this. */
2462:
2463: /* If incoming interface is passive one, ignore it. */
2464: if (oi && OSPF_IF_PASSIVE_STATUS (oi) == OSPF_IF_PASSIVE)
2465: {
2466: char buf[3][INET_ADDRSTRLEN];
2467:
2468: if (IS_DEBUG_OSPF_EVENT)
2469: zlog_debug ("ignoring packet from router %s sent to %s, "
2470: "received on a passive interface, %s",
2471: inet_ntop(AF_INET, &ospfh->router_id, buf[0], sizeof(buf[0])),
2472: inet_ntop(AF_INET, &iph->ip_dst, buf[1], sizeof(buf[1])),
2473: inet_ntop(AF_INET, &oi->address->u.prefix4,
2474: buf[2], sizeof(buf[2])));
2475:
2476: if (iph->ip_dst.s_addr == htonl(OSPF_ALLSPFROUTERS))
2477: {
2478: /* Try to fix multicast membership.
2479: * Some OS:es may have problems in this area,
2480: * make sure it is removed.
2481: */
2482: OI_MEMBER_JOINED(oi, MEMBER_ALLROUTERS);
2483: ospf_if_set_multicast(oi);
2484: }
2485: return 0;
2486: }
2487:
2488:
2489: /* if no local ospf_interface,
2490: * or header area is backbone but ospf_interface is not
2491: * check for VLINK interface
2492: */
2493: if ( (oi == NULL) ||
2494: (OSPF_IS_AREA_ID_BACKBONE(ospfh->area_id)
2495: && !OSPF_IS_AREA_ID_BACKBONE(oi->area->area_id))
2496: )
2497: {
2498: if ((oi = ospf_associate_packet_vl (ospf, ifp, iph, ospfh)) == NULL)
2499: {
2500: if (IS_DEBUG_OSPF_EVENT)
2501: zlog_debug ("Packet from [%s] received on link %s"
2502: " but no ospf_interface",
2503: inet_ntoa (iph->ip_src), ifp->name);
2504: return 0;
2505: }
2506: }
2507:
2508: /* else it must be a local ospf interface, check it was received on
2509: * correct link
2510: */
2511: else if (oi->ifp != ifp)
2512: {
2513: if (IS_DEBUG_OSPF_EVENT)
2514: zlog_warn ("Packet from [%s] received on wrong link %s",
2515: inet_ntoa (iph->ip_src), ifp->name);
2516: return 0;
2517: }
2518: else if (oi->state == ISM_Down)
2519: {
2520: char buf[2][INET_ADDRSTRLEN];
2521: zlog_warn ("Ignoring packet from %s to %s received on interface that is "
2522: "down [%s]; interface flags are %s",
2523: inet_ntop(AF_INET, &iph->ip_src, buf[0], sizeof(buf[0])),
2524: inet_ntop(AF_INET, &iph->ip_dst, buf[1], sizeof(buf[1])),
2525: ifp->name, if_flag_dump(ifp->flags));
2526: /* Fix multicast memberships? */
2527: if (iph->ip_dst.s_addr == htonl(OSPF_ALLSPFROUTERS))
2528: OI_MEMBER_JOINED(oi, MEMBER_ALLROUTERS);
2529: else if (iph->ip_dst.s_addr == htonl(OSPF_ALLDROUTERS))
2530: OI_MEMBER_JOINED(oi, MEMBER_DROUTERS);
2531: if (oi->multicast_memberships)
2532: ospf_if_set_multicast(oi);
2533: return 0;
2534: }
2535:
2536: /*
2537: * If the received packet is destined for AllDRouters, the packet
2538: * should be accepted only if the received ospf interface state is
2539: * either DR or Backup -- endo.
2540: */
2541: if (iph->ip_dst.s_addr == htonl (OSPF_ALLDROUTERS)
2542: && (oi->state != ISM_DR && oi->state != ISM_Backup))
2543: {
2544: zlog_warn ("Dropping packet for AllDRouters from [%s] via [%s] (ISM: %s)",
2545: inet_ntoa (iph->ip_src), IF_NAME (oi),
2546: LOOKUP (ospf_ism_state_msg, oi->state));
2547: /* Try to fix multicast membership. */
2548: SET_FLAG(oi->multicast_memberships, MEMBER_DROUTERS);
2549: ospf_if_set_multicast(oi);
2550: return 0;
2551: }
2552:
2553: /* Verify more OSPF header fields. */
2554: ret = ospf_verify_header (ibuf, oi, iph, ospfh);
2555: if (ret < 0)
2556: {
2557: if (IS_DEBUG_OSPF_PACKET (0, RECV))
2558: zlog_debug ("ospf_read[%s]: Header check failed, "
2559: "dropping.",
2560: inet_ntoa (iph->ip_src));
2561: return ret;
2562: }
2563:
2564: /* Show debug receiving packet. */
2565: if (IS_DEBUG_OSPF_PACKET (ospfh->type - 1, RECV))
2566: {
2567: if (IS_DEBUG_OSPF_PACKET (ospfh->type - 1, DETAIL))
2568: {
2569: zlog_debug ("-----------------------------------------------------");
2570: ospf_packet_dump (ibuf);
2571: }
2572:
2573: zlog_debug ("%s received from [%s] via [%s]",
2574: ospf_packet_type_str[ospfh->type],
2575: inet_ntoa (ospfh->router_id), IF_NAME (oi));
2576: zlog_debug (" src [%s],", inet_ntoa (iph->ip_src));
2577: zlog_debug (" dst [%s]", inet_ntoa (iph->ip_dst));
2578:
2579: if (IS_DEBUG_OSPF_PACKET (ospfh->type - 1, DETAIL))
2580: zlog_debug ("-----------------------------------------------------");
2581: }
2582:
2583: stream_forward_getp (ibuf, OSPF_HEADER_SIZE);
2584:
2585: /* Adjust size to message length. */
2586: length = ntohs (ospfh->length) - OSPF_HEADER_SIZE;
2587:
2588: /* Read rest of the packet and call each sort of packet routine. */
2589: switch (ospfh->type)
2590: {
2591: case OSPF_MSG_HELLO:
2592: ospf_hello (iph, ospfh, ibuf, oi, length);
2593: break;
2594: case OSPF_MSG_DB_DESC:
2595: ospf_db_desc (iph, ospfh, ibuf, oi, length);
2596: break;
2597: case OSPF_MSG_LS_REQ:
2598: ospf_ls_req (iph, ospfh, ibuf, oi, length);
2599: break;
2600: case OSPF_MSG_LS_UPD:
2601: ospf_ls_upd (iph, ospfh, ibuf, oi, length);
2602: break;
2603: case OSPF_MSG_LS_ACK:
2604: ospf_ls_ack (iph, ospfh, ibuf, oi, length);
2605: break;
2606: default:
2607: zlog (NULL, LOG_WARNING,
2608: "interface %s: OSPF packet header type %d is illegal",
2609: IF_NAME (oi), ospfh->type);
2610: break;
2611: }
2612:
2613: return 0;
2614: }
2615:
2616: /* Make OSPF header. */
2617: static void
2618: ospf_make_header (int type, struct ospf_interface *oi, struct stream *s)
2619: {
2620: struct ospf_header *ospfh;
2621:
2622: ospfh = (struct ospf_header *) STREAM_DATA (s);
2623:
2624: ospfh->version = (u_char) OSPF_VERSION;
2625: ospfh->type = (u_char) type;
2626:
2627: ospfh->router_id = oi->ospf->router_id;
2628:
2629: ospfh->checksum = 0;
2630: ospfh->area_id = oi->area->area_id;
2631: ospfh->auth_type = htons (ospf_auth_type (oi));
2632:
2633: memset (ospfh->u.auth_data, 0, OSPF_AUTH_SIMPLE_SIZE);
2634:
2635: stream_forward_endp (s, OSPF_HEADER_SIZE);
2636: }
2637:
2638: /* Make Authentication Data. */
2639: static int
2640: ospf_make_auth (struct ospf_interface *oi, struct ospf_header *ospfh)
2641: {
2642: struct crypt_key *ck;
2643:
2644: switch (ospf_auth_type (oi))
2645: {
2646: case OSPF_AUTH_NULL:
2647: /* memset (ospfh->u.auth_data, 0, sizeof (ospfh->u.auth_data)); */
2648: break;
2649: case OSPF_AUTH_SIMPLE:
2650: memcpy (ospfh->u.auth_data, OSPF_IF_PARAM (oi, auth_simple),
2651: OSPF_AUTH_SIMPLE_SIZE);
2652: break;
2653: case OSPF_AUTH_CRYPTOGRAPHIC:
2654: /* If key is not set, then set 0. */
2655: if (list_isempty (OSPF_IF_PARAM (oi, auth_crypt)))
2656: {
2657: ospfh->u.crypt.zero = 0;
2658: ospfh->u.crypt.key_id = 0;
2659: ospfh->u.crypt.auth_data_len = OSPF_AUTH_MD5_SIZE;
2660: }
2661: else
2662: {
2663: ck = listgetdata (listtail(OSPF_IF_PARAM (oi, auth_crypt)));
2664: ospfh->u.crypt.zero = 0;
2665: ospfh->u.crypt.key_id = ck->key_id;
2666: ospfh->u.crypt.auth_data_len = OSPF_AUTH_MD5_SIZE;
2667: }
2668: /* note: the seq is done in ospf_make_md5_digest() */
2669: break;
2670: default:
2671: /* memset (ospfh->u.auth_data, 0, sizeof (ospfh->u.auth_data)); */
2672: break;
2673: }
2674:
2675: return 0;
2676: }
2677:
2678: /* Fill rest of OSPF header. */
2679: static void
2680: ospf_fill_header (struct ospf_interface *oi,
2681: struct stream *s, u_int16_t length)
2682: {
2683: struct ospf_header *ospfh;
2684:
2685: ospfh = (struct ospf_header *) STREAM_DATA (s);
2686:
2687: /* Fill length. */
2688: ospfh->length = htons (length);
2689:
2690: /* Calculate checksum. */
2691: if (ntohs (ospfh->auth_type) != OSPF_AUTH_CRYPTOGRAPHIC)
2692: ospfh->checksum = in_cksum (ospfh, length);
2693: else
2694: ospfh->checksum = 0;
2695:
2696: /* Add Authentication Data. */
2697: ospf_make_auth (oi, ospfh);
2698: }
2699:
2700: static int
2701: ospf_make_hello (struct ospf_interface *oi, struct stream *s)
2702: {
2703: struct ospf_neighbor *nbr;
2704: struct route_node *rn;
2705: u_int16_t length = OSPF_HELLO_MIN_SIZE;
2706: struct in_addr mask;
2707: unsigned long p;
2708: int flag = 0;
2709:
2710: /* Set netmask of interface. */
2711: if (oi->type != OSPF_IFTYPE_POINTOPOINT &&
2712: oi->type != OSPF_IFTYPE_VIRTUALLINK)
2713: masklen2ip (oi->address->prefixlen, &mask);
2714: else
2715: memset ((char *) &mask, 0, sizeof (struct in_addr));
2716: stream_put_ipv4 (s, mask.s_addr);
2717:
2718: /* Set Hello Interval. */
2719: if (OSPF_IF_PARAM (oi, fast_hello) == 0)
2720: stream_putw (s, OSPF_IF_PARAM (oi, v_hello));
2721: else
2722: stream_putw (s, 0); /* hello-interval of 0 for fast-hellos */
2723:
2724: if (IS_DEBUG_OSPF_EVENT)
2725: zlog_debug ("make_hello: options: %x, int: %s",
2726: OPTIONS(oi), IF_NAME (oi));
2727:
2728: /* Set Options. */
2729: stream_putc (s, OPTIONS (oi));
2730:
2731: /* Set Router Priority. */
2732: stream_putc (s, PRIORITY (oi));
2733:
2734: /* Set Router Dead Interval. */
2735: stream_putl (s, OSPF_IF_PARAM (oi, v_wait));
2736:
2737: /* Set Designated Router. */
2738: stream_put_ipv4 (s, DR (oi).s_addr);
2739:
2740: p = stream_get_endp (s);
2741:
2742: /* Set Backup Designated Router. */
2743: stream_put_ipv4 (s, BDR (oi).s_addr);
2744:
2745: /* Add neighbor seen. */
2746: for (rn = route_top (oi->nbrs); rn; rn = route_next (rn))
2747: if ((nbr = rn->info))
2748: if (nbr->router_id.s_addr != 0) /* Ignore 0.0.0.0 node. */
2749: if (nbr->state != NSM_Attempt) /* Ignore Down neighbor. */
2750: if (nbr->state != NSM_Down) /* This is myself for DR election. */
2751: if (!IPV4_ADDR_SAME (&nbr->router_id, &oi->ospf->router_id))
2752: {
2753: /* Check neighbor is sane? */
2754: if (nbr->d_router.s_addr != 0
2755: && IPV4_ADDR_SAME (&nbr->d_router, &oi->address->u.prefix4)
2756: && IPV4_ADDR_SAME (&nbr->bd_router, &oi->address->u.prefix4))
2757: flag = 1;
2758:
2759: stream_put_ipv4 (s, nbr->router_id.s_addr);
2760: length += 4;
2761: }
2762:
2763: /* Let neighbor generate BackupSeen. */
2764: if (flag == 1)
2765: stream_putl_at (s, p, 0); /* ipv4 address, normally */
2766:
2767: return length;
2768: }
2769:
2770: static int
2771: ospf_make_db_desc (struct ospf_interface *oi, struct ospf_neighbor *nbr,
2772: struct stream *s)
2773: {
2774: struct ospf_lsa *lsa;
2775: u_int16_t length = OSPF_DB_DESC_MIN_SIZE;
2776: u_char options;
2777: unsigned long pp;
2778: int i;
2779: struct ospf_lsdb *lsdb;
2780:
2781: /* Set Interface MTU. */
2782: if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
2783: stream_putw (s, 0);
2784: else
2785: stream_putw (s, oi->ifp->mtu);
2786:
2787: /* Set Options. */
2788: options = OPTIONS (oi);
2789: #ifdef HAVE_OPAQUE_LSA
2790: if (CHECK_FLAG (oi->ospf->config, OSPF_OPAQUE_CAPABLE))
2791: {
2792: if (IS_SET_DD_I (nbr->dd_flags)
2793: || CHECK_FLAG (nbr->options, OSPF_OPTION_O))
2794: /*
2795: * Set O-bit in the outgoing DD packet for capablity negotiation,
2796: * if one of following case is applicable.
2797: *
2798: * 1) WaitTimer expiration event triggered the neighbor state to
2799: * change to Exstart, but no (valid) DD packet has received
2800: * from the neighbor yet.
2801: *
2802: * 2) At least one DD packet with O-bit on has received from the
2803: * neighbor.
2804: */
2805: SET_FLAG (options, OSPF_OPTION_O);
2806: }
2807: #endif /* HAVE_OPAQUE_LSA */
2808: stream_putc (s, options);
2809:
2810: /* DD flags */
2811: pp = stream_get_endp (s);
2812: stream_putc (s, nbr->dd_flags);
2813:
2814: /* Set DD Sequence Number. */
2815: stream_putl (s, nbr->dd_seqnum);
2816:
2817: /* shortcut unneeded walk of (empty) summary LSDBs */
2818: if (ospf_db_summary_isempty (nbr))
2819: goto empty;
2820:
2821: /* Describe LSA Header from Database Summary List. */
2822: lsdb = &nbr->db_sum;
2823:
2824: for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
2825: {
2826: struct route_table *table = lsdb->type[i].db;
2827: struct route_node *rn;
2828:
2829: for (rn = route_top (table); rn; rn = route_next (rn))
2830: if ((lsa = rn->info) != NULL)
2831: {
2832: #ifdef HAVE_OPAQUE_LSA
2833: if (IS_OPAQUE_LSA (lsa->data->type)
2834: && (! CHECK_FLAG (options, OSPF_OPTION_O)))
2835: {
2836: /* Suppress advertising opaque-informations. */
2837: /* Remove LSA from DB summary list. */
2838: ospf_lsdb_delete (lsdb, lsa);
2839: continue;
2840: }
2841: #endif /* HAVE_OPAQUE_LSA */
2842:
2843: if (!CHECK_FLAG (lsa->flags, OSPF_LSA_DISCARD))
2844: {
2845: struct lsa_header *lsah;
2846: u_int16_t ls_age;
2847:
2848: /* DD packet overflows interface MTU. */
2849: if (length + OSPF_LSA_HEADER_SIZE > ospf_packet_max (oi))
2850: break;
2851:
2852: /* Keep pointer to LS age. */
2853: lsah = (struct lsa_header *) (STREAM_DATA (s) +
2854: stream_get_endp (s));
2855:
2856: /* Proceed stream pointer. */
2857: stream_put (s, lsa->data, OSPF_LSA_HEADER_SIZE);
2858: length += OSPF_LSA_HEADER_SIZE;
2859:
2860: /* Set LS age. */
2861: ls_age = LS_AGE (lsa);
2862: lsah->ls_age = htons (ls_age);
2863:
2864: }
2865:
2866: /* Remove LSA from DB summary list. */
2867: ospf_lsdb_delete (lsdb, lsa);
2868: }
2869: }
2870:
2871: /* Update 'More' bit */
2872: if (ospf_db_summary_isempty (nbr))
2873: {
2874: empty:
2875: if (nbr->state >= NSM_Exchange)
2876: {
2877: UNSET_FLAG (nbr->dd_flags, OSPF_DD_FLAG_M);
2878: /* Rewrite DD flags */
2879: stream_putc_at (s, pp, nbr->dd_flags);
2880: }
2881: else
2882: {
2883: assert (IS_SET_DD_M(nbr->dd_flags));
2884: }
2885: }
2886: return length;
2887: }
2888:
2889: static int
2890: ospf_make_ls_req_func (struct stream *s, u_int16_t *length,
2891: unsigned long delta, struct ospf_neighbor *nbr,
2892: struct ospf_lsa *lsa)
2893: {
2894: struct ospf_interface *oi;
2895:
2896: oi = nbr->oi;
2897:
2898: /* LS Request packet overflows interface MTU. */
2899: if (*length + delta > ospf_packet_max(oi))
2900: return 0;
2901:
2902: stream_putl (s, lsa->data->type);
2903: stream_put_ipv4 (s, lsa->data->id.s_addr);
2904: stream_put_ipv4 (s, lsa->data->adv_router.s_addr);
2905:
2906: ospf_lsa_unlock (&nbr->ls_req_last);
2907: nbr->ls_req_last = ospf_lsa_lock (lsa);
2908:
2909: *length += 12;
2910: return 1;
2911: }
2912:
2913: static int
2914: ospf_make_ls_req (struct ospf_neighbor *nbr, struct stream *s)
2915: {
2916: struct ospf_lsa *lsa;
2917: u_int16_t length = OSPF_LS_REQ_MIN_SIZE;
2918: unsigned long delta = stream_get_endp(s)+12;
2919: struct route_table *table;
2920: struct route_node *rn;
2921: int i;
2922: struct ospf_lsdb *lsdb;
2923:
2924: lsdb = &nbr->ls_req;
2925:
2926: for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
2927: {
2928: table = lsdb->type[i].db;
2929: for (rn = route_top (table); rn; rn = route_next (rn))
2930: if ((lsa = (rn->info)) != NULL)
2931: if (ospf_make_ls_req_func (s, &length, delta, nbr, lsa) == 0)
2932: {
2933: route_unlock_node (rn);
2934: break;
2935: }
2936: }
2937: return length;
2938: }
2939:
2940: static int
2941: ls_age_increment (struct ospf_lsa *lsa, int delay)
2942: {
2943: int age;
2944:
2945: age = IS_LSA_MAXAGE (lsa) ? OSPF_LSA_MAXAGE : LS_AGE (lsa) + delay;
2946:
2947: return (age > OSPF_LSA_MAXAGE ? OSPF_LSA_MAXAGE : age);
2948: }
2949:
2950: static int
2951: ospf_make_ls_upd (struct ospf_interface *oi, struct list *update, struct stream *s)
2952: {
2953: struct ospf_lsa *lsa;
2954: struct listnode *node;
2955: u_int16_t length = 0;
2956: unsigned int size_noauth;
2957: unsigned long delta = stream_get_endp (s);
2958: unsigned long pp;
2959: int count = 0;
2960:
2961: if (IS_DEBUG_OSPF_EVENT)
2962: zlog_debug ("ospf_make_ls_upd: Start");
2963:
2964: pp = stream_get_endp (s);
2965: stream_forward_endp (s, OSPF_LS_UPD_MIN_SIZE);
2966: length += OSPF_LS_UPD_MIN_SIZE;
2967:
2968: /* Calculate amount of packet usable for data. */
2969: size_noauth = stream_get_size(s) - ospf_packet_authspace(oi);
2970:
2971: while ((node = listhead (update)) != NULL)
2972: {
2973: struct lsa_header *lsah;
2974: u_int16_t ls_age;
2975:
2976: if (IS_DEBUG_OSPF_EVENT)
2977: zlog_debug ("ospf_make_ls_upd: List Iteration");
2978:
2979: lsa = listgetdata (node);
2980:
2981: assert (lsa->data);
2982:
2983: /* Will it fit? */
2984: if (length + delta + ntohs (lsa->data->length) > size_noauth)
2985: break;
2986:
2987: /* Keep pointer to LS age. */
2988: lsah = (struct lsa_header *) (STREAM_DATA (s) + stream_get_endp (s));
2989:
2990: /* Put LSA to Link State Request. */
2991: stream_put (s, lsa->data, ntohs (lsa->data->length));
2992:
2993: /* Set LS age. */
2994: /* each hop must increment an lsa_age by transmit_delay
2995: of OSPF interface */
2996: ls_age = ls_age_increment (lsa, OSPF_IF_PARAM (oi, transmit_delay));
2997: lsah->ls_age = htons (ls_age);
2998:
2999: length += ntohs (lsa->data->length);
3000: count++;
3001:
3002: list_delete_node (update, node);
3003: ospf_lsa_unlock (&lsa); /* oi->ls_upd_queue */
3004: }
3005:
3006: /* Now set #LSAs. */
3007: stream_putl_at (s, pp, count);
3008:
3009: if (IS_DEBUG_OSPF_EVENT)
3010: zlog_debug ("ospf_make_ls_upd: Stop");
3011: return length;
3012: }
3013:
3014: static int
3015: ospf_make_ls_ack (struct ospf_interface *oi, struct list *ack, struct stream *s)
3016: {
3017: struct listnode *node, *nnode;
3018: u_int16_t length = OSPF_LS_ACK_MIN_SIZE;
3019: unsigned long delta = stream_get_endp(s) + 24;
3020: struct ospf_lsa *lsa;
3021:
3022: for (ALL_LIST_ELEMENTS (ack, node, nnode, lsa))
3023: {
3024: assert (lsa);
3025:
3026: if (length + delta > ospf_packet_max (oi))
3027: break;
3028:
3029: stream_put (s, lsa->data, OSPF_LSA_HEADER_SIZE);
3030: length += OSPF_LSA_HEADER_SIZE;
3031:
3032: listnode_delete (ack, lsa);
3033: ospf_lsa_unlock (&lsa); /* oi->ls_ack_direct.ls_ack */
3034: }
3035:
3036: return length;
3037: }
3038:
3039: static void
3040: ospf_hello_send_sub (struct ospf_interface *oi, in_addr_t addr)
3041: {
3042: struct ospf_packet *op;
3043: u_int16_t length = OSPF_HEADER_SIZE;
3044:
3045: op = ospf_packet_new (oi->ifp->mtu);
3046:
3047: /* Prepare OSPF common header. */
3048: ospf_make_header (OSPF_MSG_HELLO, oi, op->s);
3049:
3050: /* Prepare OSPF Hello body. */
3051: length += ospf_make_hello (oi, op->s);
3052:
3053: /* Fill OSPF header. */
3054: ospf_fill_header (oi, op->s, length);
3055:
3056: /* Set packet length. */
3057: op->length = length;
3058:
3059: op->dst.s_addr = addr;
3060:
3061: /* Add packet to the top of the interface output queue, so that they
3062: * can't get delayed by things like long queues of LS Update packets
3063: */
3064: ospf_packet_add_top (oi, op);
3065:
3066: /* Hook thread to write packet. */
3067: OSPF_ISM_WRITE_ON (oi->ospf);
3068: }
3069:
3070: static void
3071: ospf_poll_send (struct ospf_nbr_nbma *nbr_nbma)
3072: {
3073: struct ospf_interface *oi;
3074:
3075: oi = nbr_nbma->oi;
3076: assert(oi);
3077:
3078: /* If this is passive interface, do not send OSPF Hello. */
3079: if (OSPF_IF_PASSIVE_STATUS (oi) == OSPF_IF_PASSIVE)
3080: return;
3081:
3082: if (oi->type != OSPF_IFTYPE_NBMA)
3083: return;
3084:
3085: if (nbr_nbma->nbr != NULL && nbr_nbma->nbr->state != NSM_Down)
3086: return;
3087:
3088: if (PRIORITY(oi) == 0)
3089: return;
3090:
3091: if (nbr_nbma->priority == 0
3092: && oi->state != ISM_DR && oi->state != ISM_Backup)
3093: return;
3094:
3095: ospf_hello_send_sub (oi, nbr_nbma->addr.s_addr);
3096: }
3097:
3098: int
3099: ospf_poll_timer (struct thread *thread)
3100: {
3101: struct ospf_nbr_nbma *nbr_nbma;
3102:
3103: nbr_nbma = THREAD_ARG (thread);
3104: nbr_nbma->t_poll = NULL;
3105:
3106: if (IS_DEBUG_OSPF (nsm, NSM_TIMERS))
3107: zlog (NULL, LOG_DEBUG, "NSM[%s:%s]: Timer (Poll timer expire)",
3108: IF_NAME (nbr_nbma->oi), inet_ntoa (nbr_nbma->addr));
3109:
3110: ospf_poll_send (nbr_nbma);
3111:
3112: if (nbr_nbma->v_poll > 0)
3113: OSPF_POLL_TIMER_ON (nbr_nbma->t_poll, ospf_poll_timer,
3114: nbr_nbma->v_poll);
3115:
3116: return 0;
3117: }
3118:
3119:
3120: int
3121: ospf_hello_reply_timer (struct thread *thread)
3122: {
3123: struct ospf_neighbor *nbr;
3124:
3125: nbr = THREAD_ARG (thread);
3126: nbr->t_hello_reply = NULL;
3127:
3128: assert (nbr->oi);
3129:
3130: if (IS_DEBUG_OSPF (nsm, NSM_TIMERS))
3131: zlog (NULL, LOG_DEBUG, "NSM[%s:%s]: Timer (hello-reply timer expire)",
3132: IF_NAME (nbr->oi), inet_ntoa (nbr->router_id));
3133:
3134: ospf_hello_send_sub (nbr->oi, nbr->address.u.prefix4.s_addr);
3135:
3136: return 0;
3137: }
3138:
3139: /* Send OSPF Hello. */
3140: void
3141: ospf_hello_send (struct ospf_interface *oi)
3142: {
3143: /* If this is passive interface, do not send OSPF Hello. */
3144: if (OSPF_IF_PASSIVE_STATUS (oi) == OSPF_IF_PASSIVE)
3145: return;
3146:
3147: if (oi->type == OSPF_IFTYPE_NBMA)
3148: {
3149: struct ospf_neighbor *nbr;
3150: struct route_node *rn;
3151:
3152: for (rn = route_top (oi->nbrs); rn; rn = route_next (rn))
3153: if ((nbr = rn->info))
3154: if (nbr != oi->nbr_self)
3155: if (nbr->state != NSM_Down)
3156: {
3157: /* RFC 2328 Section 9.5.1
3158: If the router is not eligible to become Designated Router,
3159: it must periodically send Hello Packets to both the
3160: Designated Router and the Backup Designated Router (if they
3161: exist). */
3162: if (PRIORITY(oi) == 0 &&
3163: IPV4_ADDR_CMP(&DR(oi), &nbr->address.u.prefix4) &&
3164: IPV4_ADDR_CMP(&BDR(oi), &nbr->address.u.prefix4))
3165: continue;
3166:
3167: /* If the router is eligible to become Designated Router, it
3168: must periodically send Hello Packets to all neighbors that
3169: are also eligible. In addition, if the router is itself the
3170: Designated Router or Backup Designated Router, it must also
3171: send periodic Hello Packets to all other neighbors. */
3172:
3173: if (nbr->priority == 0 && oi->state == ISM_DROther)
3174: continue;
3175: /* if oi->state == Waiting, send hello to all neighbors */
3176: ospf_hello_send_sub (oi, nbr->address.u.prefix4.s_addr);
3177: }
3178: }
3179: else
3180: {
3181: /* Decide destination address. */
3182: if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
3183: ospf_hello_send_sub (oi, oi->vl_data->peer_addr.s_addr);
3184: else
3185: ospf_hello_send_sub (oi, htonl (OSPF_ALLSPFROUTERS));
3186: }
3187: }
3188:
3189: /* Send OSPF Database Description. */
3190: void
3191: ospf_db_desc_send (struct ospf_neighbor *nbr)
3192: {
3193: struct ospf_interface *oi;
3194: struct ospf_packet *op;
3195: u_int16_t length = OSPF_HEADER_SIZE;
3196:
3197: oi = nbr->oi;
3198: op = ospf_packet_new (oi->ifp->mtu);
3199:
3200: /* Prepare OSPF common header. */
3201: ospf_make_header (OSPF_MSG_DB_DESC, oi, op->s);
3202:
3203: /* Prepare OSPF Database Description body. */
3204: length += ospf_make_db_desc (oi, nbr, op->s);
3205:
3206: /* Fill OSPF header. */
3207: ospf_fill_header (oi, op->s, length);
3208:
3209: /* Set packet length. */
3210: op->length = length;
3211:
3212: /* Decide destination address. */
3213: if (oi->type == OSPF_IFTYPE_POINTOPOINT)
3214: op->dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3215: else
3216: op->dst = nbr->address.u.prefix4;
3217:
3218: /* Add packet to the interface output queue. */
3219: ospf_packet_add (oi, op);
3220:
3221: /* Hook thread to write packet. */
3222: OSPF_ISM_WRITE_ON (oi->ospf);
3223:
3224: /* Remove old DD packet, then copy new one and keep in neighbor structure. */
3225: if (nbr->last_send)
3226: ospf_packet_free (nbr->last_send);
3227: nbr->last_send = ospf_packet_dup (op);
3228: quagga_gettime (QUAGGA_CLK_MONOTONIC, &nbr->last_send_ts);
3229: }
3230:
3231: /* Re-send Database Description. */
3232: void
3233: ospf_db_desc_resend (struct ospf_neighbor *nbr)
3234: {
3235: struct ospf_interface *oi;
3236:
3237: oi = nbr->oi;
3238:
3239: /* Add packet to the interface output queue. */
3240: ospf_packet_add (oi, ospf_packet_dup (nbr->last_send));
3241:
3242: /* Hook thread to write packet. */
3243: OSPF_ISM_WRITE_ON (oi->ospf);
3244: }
3245:
3246: /* Send Link State Request. */
3247: void
3248: ospf_ls_req_send (struct ospf_neighbor *nbr)
3249: {
3250: struct ospf_interface *oi;
3251: struct ospf_packet *op;
3252: u_int16_t length = OSPF_HEADER_SIZE;
3253:
3254: oi = nbr->oi;
3255: op = ospf_packet_new (oi->ifp->mtu);
3256:
3257: /* Prepare OSPF common header. */
3258: ospf_make_header (OSPF_MSG_LS_REQ, oi, op->s);
3259:
3260: /* Prepare OSPF Link State Request body. */
3261: length += ospf_make_ls_req (nbr, op->s);
3262: if (length == OSPF_HEADER_SIZE)
3263: {
3264: ospf_packet_free (op);
3265: return;
3266: }
3267:
3268: /* Fill OSPF header. */
3269: ospf_fill_header (oi, op->s, length);
3270:
3271: /* Set packet length. */
3272: op->length = length;
3273:
3274: /* Decide destination address. */
3275: if (oi->type == OSPF_IFTYPE_POINTOPOINT)
3276: op->dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3277: else
3278: op->dst = nbr->address.u.prefix4;
3279:
3280: /* Add packet to the interface output queue. */
3281: ospf_packet_add (oi, op);
3282:
3283: /* Hook thread to write packet. */
3284: OSPF_ISM_WRITE_ON (oi->ospf);
3285:
3286: /* Add Link State Request Retransmission Timer. */
3287: OSPF_NSM_TIMER_ON (nbr->t_ls_req, ospf_ls_req_timer, nbr->v_ls_req);
3288: }
3289:
3290: /* Send Link State Update with an LSA. */
3291: void
3292: ospf_ls_upd_send_lsa (struct ospf_neighbor *nbr, struct ospf_lsa *lsa,
3293: int flag)
3294: {
3295: struct list *update;
3296:
3297: update = list_new ();
3298:
3299: listnode_add (update, lsa);
3300: ospf_ls_upd_send (nbr, update, flag);
3301:
3302: list_delete (update);
3303: }
3304:
3305: /* Determine size for packet. Must be at least big enough to accomodate next
3306: * LSA on list, which may be bigger than MTU size.
3307: *
3308: * Return pointer to new ospf_packet
3309: * NULL if we can not allocate, eg because LSA is bigger than imposed limit
3310: * on packet sizes (in which case offending LSA is deleted from update list)
3311: */
3312: static struct ospf_packet *
3313: ospf_ls_upd_packet_new (struct list *update, struct ospf_interface *oi)
3314: {
3315: struct ospf_lsa *lsa;
3316: struct listnode *ln;
3317: size_t size;
3318: static char warned = 0;
3319:
3320: lsa = listgetdata((ln = listhead (update)));
3321: assert (lsa->data);
3322:
3323: if ((OSPF_LS_UPD_MIN_SIZE + ntohs (lsa->data->length))
3324: > ospf_packet_max (oi))
3325: {
3326: if (!warned)
3327: {
3328: zlog_warn ("ospf_ls_upd_packet_new: oversized LSA encountered!"
3329: "will need to fragment. Not optimal. Try divide up"
3330: " your network with areas. Use 'debug ospf packet send'"
3331: " to see details, or look at 'show ip ospf database ..'");
3332: warned = 1;
3333: }
3334:
3335: if (IS_DEBUG_OSPF_PACKET (0, SEND))
3336: zlog_debug ("ospf_ls_upd_packet_new: oversized LSA id:%s,"
3337: " %d bytes originated by %s, will be fragmented!",
3338: inet_ntoa (lsa->data->id),
3339: ntohs (lsa->data->length),
3340: inet_ntoa (lsa->data->adv_router));
3341:
3342: /*
3343: * Allocate just enough to fit this LSA only, to avoid including other
3344: * LSAs in fragmented LSA Updates.
3345: */
3346: size = ntohs (lsa->data->length) + (oi->ifp->mtu - ospf_packet_max (oi))
3347: + OSPF_LS_UPD_MIN_SIZE;
3348: }
3349: else
3350: size = oi->ifp->mtu;
3351:
3352: if (size > OSPF_MAX_PACKET_SIZE)
3353: {
3354: zlog_warn ("ospf_ls_upd_packet_new: oversized LSA id:%s too big,"
3355: " %d bytes, packet size %ld, dropping it completely."
3356: " OSPF routing is broken!",
3357: inet_ntoa (lsa->data->id), ntohs (lsa->data->length),
3358: (long int) size);
3359: list_delete_node (update, ln);
3360: return NULL;
3361: }
3362:
3363: /* IP header is built up separately by ospf_write(). This means, that we must
3364: * reduce the "affordable" size just calculated by length of an IP header.
3365: * This makes sure, that even if we manage to fill the payload with LSA data
3366: * completely, the final packet (our data plus IP header) still fits into
3367: * outgoing interface MTU. This correction isn't really meaningful for an
3368: * oversized LSA, but for consistency the correction is done for both cases.
3369: *
3370: * P.S. OSPF_MAX_PACKET_SIZE above already includes IP header size
3371: */
3372: return ospf_packet_new (size - sizeof (struct ip));
3373: }
3374:
3375: static void
3376: ospf_ls_upd_queue_send (struct ospf_interface *oi, struct list *update,
3377: struct in_addr addr)
3378: {
3379: struct ospf_packet *op;
3380: u_int16_t length = OSPF_HEADER_SIZE;
3381:
3382: if (IS_DEBUG_OSPF_EVENT)
3383: zlog_debug ("listcount = %d, dst %s", listcount (update), inet_ntoa(addr));
3384:
3385: op = ospf_ls_upd_packet_new (update, oi);
3386:
3387: /* Prepare OSPF common header. */
3388: ospf_make_header (OSPF_MSG_LS_UPD, oi, op->s);
3389:
3390: /* Prepare OSPF Link State Update body.
3391: * Includes Type-7 translation.
3392: */
3393: length += ospf_make_ls_upd (oi, update, op->s);
3394:
3395: /* Fill OSPF header. */
3396: ospf_fill_header (oi, op->s, length);
3397:
3398: /* Set packet length. */
3399: op->length = length;
3400:
3401: /* Decide destination address. */
3402: if (oi->type == OSPF_IFTYPE_POINTOPOINT)
3403: op->dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3404: else
3405: op->dst.s_addr = addr.s_addr;
3406:
3407: /* Add packet to the interface output queue. */
3408: ospf_packet_add (oi, op);
3409:
3410: /* Hook thread to write packet. */
3411: OSPF_ISM_WRITE_ON (oi->ospf);
3412: }
3413:
3414: static int
3415: ospf_ls_upd_send_queue_event (struct thread *thread)
3416: {
3417: struct ospf_interface *oi = THREAD_ARG(thread);
3418: struct route_node *rn;
3419: struct route_node *rnext;
3420: struct list *update;
3421: char again = 0;
3422:
3423: oi->t_ls_upd_event = NULL;
3424:
3425: if (IS_DEBUG_OSPF_EVENT)
3426: zlog_debug ("ospf_ls_upd_send_queue start");
3427:
3428: for (rn = route_top (oi->ls_upd_queue); rn; rn = rnext)
3429: {
3430: rnext = route_next (rn);
3431:
3432: if (rn->info == NULL)
3433: continue;
3434:
3435: update = (struct list *)rn->info;
3436:
3437: ospf_ls_upd_queue_send (oi, update, rn->p.u.prefix4);
3438:
3439: /* list might not be empty. */
3440: if (listcount(update) == 0)
3441: {
3442: list_delete (rn->info);
3443: rn->info = NULL;
3444: route_unlock_node (rn);
3445: }
3446: else
3447: again = 1;
3448: }
3449:
3450: if (again != 0)
3451: {
3452: if (IS_DEBUG_OSPF_EVENT)
3453: zlog_debug ("ospf_ls_upd_send_queue: update lists not cleared,"
3454: " %d nodes to try again, raising new event", again);
3455: oi->t_ls_upd_event =
3456: thread_add_event (master, ospf_ls_upd_send_queue_event, oi, 0);
3457: }
3458:
3459: if (IS_DEBUG_OSPF_EVENT)
3460: zlog_debug ("ospf_ls_upd_send_queue stop");
3461:
3462: return 0;
3463: }
3464:
3465: void
3466: ospf_ls_upd_send (struct ospf_neighbor *nbr, struct list *update, int flag)
3467: {
3468: struct ospf_interface *oi;
3469: struct ospf_lsa *lsa;
3470: struct prefix_ipv4 p;
3471: struct route_node *rn;
3472: struct listnode *node;
3473:
3474: oi = nbr->oi;
3475:
3476: p.family = AF_INET;
3477: p.prefixlen = IPV4_MAX_BITLEN;
3478:
3479: /* Decide destination address. */
3480: if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
3481: p.prefix = oi->vl_data->peer_addr;
3482: else if (oi->type == OSPF_IFTYPE_POINTOPOINT)
3483: p.prefix.s_addr = htonl (OSPF_ALLSPFROUTERS);
3484: else if (flag == OSPF_SEND_PACKET_DIRECT)
3485: p.prefix = nbr->address.u.prefix4;
3486: else if (oi->state == ISM_DR || oi->state == ISM_Backup)
3487: p.prefix.s_addr = htonl (OSPF_ALLSPFROUTERS);
3488: else if (oi->type == OSPF_IFTYPE_POINTOMULTIPOINT)
3489: p.prefix.s_addr = htonl (OSPF_ALLSPFROUTERS);
3490: else
3491: p.prefix.s_addr = htonl (OSPF_ALLDROUTERS);
3492:
3493: if (oi->type == OSPF_IFTYPE_NBMA)
3494: {
3495: if (flag == OSPF_SEND_PACKET_INDIRECT)
3496: zlog_warn ("* LS-Update is directly sent on NBMA network.");
3497: if (IPV4_ADDR_SAME(&oi->address->u.prefix4, &p.prefix.s_addr))
3498: zlog_warn ("* LS-Update is sent to myself.");
3499: }
3500:
3501: rn = route_node_get (oi->ls_upd_queue, (struct prefix *) &p);
3502:
3503: if (rn->info == NULL)
3504: rn->info = list_new ();
3505:
3506: for (ALL_LIST_ELEMENTS_RO (update, node, lsa))
3507: listnode_add (rn->info, ospf_lsa_lock (lsa)); /* oi->ls_upd_queue */
3508:
3509: if (oi->t_ls_upd_event == NULL)
3510: oi->t_ls_upd_event =
3511: thread_add_event (master, ospf_ls_upd_send_queue_event, oi, 0);
3512: }
3513:
3514: static void
3515: ospf_ls_ack_send_list (struct ospf_interface *oi, struct list *ack,
3516: struct in_addr dst)
3517: {
3518: struct ospf_packet *op;
3519: u_int16_t length = OSPF_HEADER_SIZE;
3520:
3521: op = ospf_packet_new (oi->ifp->mtu);
3522:
3523: /* Prepare OSPF common header. */
3524: ospf_make_header (OSPF_MSG_LS_ACK, oi, op->s);
3525:
3526: /* Prepare OSPF Link State Acknowledgment body. */
3527: length += ospf_make_ls_ack (oi, ack, op->s);
3528:
3529: /* Fill OSPF header. */
3530: ospf_fill_header (oi, op->s, length);
3531:
3532: /* Set packet length. */
3533: op->length = length;
3534:
3535: /* Set destination IP address. */
3536: op->dst = dst;
3537:
3538: /* Add packet to the interface output queue. */
3539: ospf_packet_add (oi, op);
3540:
3541: /* Hook thread to write packet. */
3542: OSPF_ISM_WRITE_ON (oi->ospf);
3543: }
3544:
3545: static int
3546: ospf_ls_ack_send_event (struct thread *thread)
3547: {
3548: struct ospf_interface *oi = THREAD_ARG (thread);
3549:
3550: oi->t_ls_ack_direct = NULL;
3551:
3552: while (listcount (oi->ls_ack_direct.ls_ack))
3553: ospf_ls_ack_send_list (oi, oi->ls_ack_direct.ls_ack,
3554: oi->ls_ack_direct.dst);
3555:
3556: return 0;
3557: }
3558:
3559: void
3560: ospf_ls_ack_send (struct ospf_neighbor *nbr, struct ospf_lsa *lsa)
3561: {
3562: struct ospf_interface *oi = nbr->oi;
3563:
3564: if (listcount (oi->ls_ack_direct.ls_ack) == 0)
3565: oi->ls_ack_direct.dst = nbr->address.u.prefix4;
3566:
3567: listnode_add (oi->ls_ack_direct.ls_ack, ospf_lsa_lock (lsa));
3568:
3569: if (oi->t_ls_ack_direct == NULL)
3570: oi->t_ls_ack_direct =
3571: thread_add_event (master, ospf_ls_ack_send_event, oi, 0);
3572: }
3573:
3574: /* Send Link State Acknowledgment delayed. */
3575: void
3576: ospf_ls_ack_send_delayed (struct ospf_interface *oi)
3577: {
3578: struct in_addr dst;
3579:
3580: /* Decide destination address. */
3581: /* RFC2328 Section 13.5 On non-broadcast
3582: networks, delayed Link State Acknowledgment packets must be
3583: unicast separately over each adjacency (i.e., neighbor whose
3584: state is >= Exchange). */
3585: if (oi->type == OSPF_IFTYPE_NBMA)
3586: {
3587: struct ospf_neighbor *nbr;
3588: struct route_node *rn;
3589:
3590: for (rn = route_top (oi->nbrs); rn; rn = route_next (rn))
3591: if ((nbr = rn->info) != NULL)
3592: if (nbr != oi->nbr_self && nbr->state >= NSM_Exchange)
3593: while (listcount (oi->ls_ack))
3594: ospf_ls_ack_send_list (oi, oi->ls_ack, nbr->address.u.prefix4);
3595: return;
3596: }
3597: if (oi->type == OSPF_IFTYPE_VIRTUALLINK)
3598: dst.s_addr = oi->vl_data->peer_addr.s_addr;
3599: else if (oi->state == ISM_DR || oi->state == ISM_Backup)
3600: dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3601: else if (oi->type == OSPF_IFTYPE_POINTOPOINT)
3602: dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3603: else if (oi->type == OSPF_IFTYPE_POINTOMULTIPOINT)
3604: dst.s_addr = htonl (OSPF_ALLSPFROUTERS);
3605: else
3606: dst.s_addr = htonl (OSPF_ALLDROUTERS);
3607:
3608: while (listcount (oi->ls_ack))
3609: ospf_ls_ack_send_list (oi, oi->ls_ack, dst);
3610: }
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