summaryrefslogtreecommitdiffstats
path: root/usr.sbin/rtadvd/rtadvd.c
blob: 03ed974f656aea596a882c85c0d76dfc96d4cd67 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/time.h>

#include <net/if.h>
#include <net/route.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>

#include <arpa/inet.h>

#ifdef IPSEC
#include <netinet6/ipsec.h>
#endif /*IPSEC*/

#include <time.h>
#include <unistd.h>
#include <stdio.h>
#include <err.h>
#include <errno.h>
#include <string.h>
#include <sysexits.h>
#include <stdlib.h>
#include <syslog.h>
#include "rtadvd.h"
#include "rrenum.h"
#include "advcap.h"
#include "timer.h"
#include "if.h"
#include "config.h"

struct	msghdr rcvmhdr;
static u_char	rcvcmsgbuf[CMSG_SPACE(sizeof(struct in6_pktinfo)) +
			CMSG_SPACE(sizeof(int))];
struct	msghdr sndmhdr;
struct	iovec rcviov[2];
struct	iovec sndiov[2];
struct	sockaddr_in6 from;
struct	sockaddr_in6 sin6_allnodes = {sizeof(sin6_allnodes), AF_INET6};
int	sock, rrsock, rtsock;
int	accept_rr = 0;
int	dflag = 0, sflag = 0;

u_char	*conffile = NULL;

struct	rainfo *ralist = NULL;
struct	nd_optlist {
	struct	nd_optlist *next;
	struct	nd_opt_hdr *opt;
};
union nd_opts {
	struct	nd_opt_hdr *nd_opt_array[7];
	struct {
		struct	nd_opt_hdr *zero;
		struct	nd_opt_hdr *src_lladdr;
		struct	nd_opt_hdr *tgt_lladdr;
		struct	nd_opt_prefix_info *pi;
		struct	nd_opt_rd_hdr *rh;
		struct	nd_opt_mtu *mtu;
		struct	nd_optlist *list;
	} nd_opt_each;
};
#define	nd_opts_src_lladdr	nd_opt_each.src_lladdr
#define	nd_opts_tgt_lladdr	nd_opt_each.tgt_lladdr
#define	nd_opts_pi		nd_opt_each.pi
#define	nd_opts_rh		nd_opt_each.rh
#define	nd_opts_mtu		nd_opt_each.mtu
#define	nd_opts_list		nd_opt_each.list

#define	NDOPT_FLAG_SRCLINKADDR 0x1
#define	NDOPT_FLAG_TGTLINKADDR 0x2
#define	NDOPT_FLAG_PREFIXINFO 0x4
#define	NDOPT_FLAG_RDHDR 0x8
#define	NDOPT_FLAG_MTU 0x10

u_int32_t ndopt_flags[] = {
	0, NDOPT_FLAG_SRCLINKADDR, NDOPT_FLAG_TGTLINKADDR,
	NDOPT_FLAG_PREFIXINFO, NDOPT_FLAG_RDHDR, NDOPT_FLAG_MTU
};

int	main __P((int, char *[]));
static void	sock_open __P((int *, int, char *));
static void	rtsock_open __P((void));
static void	rtadvd_input __P((int));
static void	rs_input __P((int, struct nd_router_solicit *,
			  struct in6_pktinfo *, struct sockaddr_in6 *));
static void	ra_input __P((int, struct nd_router_advert *,
			  struct in6_pktinfo *, struct sockaddr_in6 *));
static void	prefix_check __P((struct nd_opt_prefix_info *, struct rainfo *,
			      struct sockaddr_in6 *));
static int	nd6_options __P((struct nd_opt_hdr *, int,
			    union nd_opts *, u_int32_t));
static void	free_ndopts __P((union nd_opts *));
static struct	rainfo *if_indextorainfo __P((int));
static void	ra_output __P((struct rainfo *));
static void	rtmsg_input __P((void));
struct	prefix *find_prefix __P((struct rainfo *, struct in6_addr *, int));


int
main(argc, argv)
	int argc;
	char *argv[];
{
	fd_set fdset;
	int maxfd = 0;
	struct timeval *timeout;
	int i, ch;
	int fflag = 0;
#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
	char *policy = NULL;
#endif /*IPSEC_POLICY_IPSEC*/
#endif /*IPSEC*/

	openlog(*argv, LOG_NDELAY|LOG_PID, LOG_DAEMON);

	/* get command line options and arguments */
	while ((ch = getopt(argc, argv, "c:dDfR:s")) != -1) {
		switch(ch) {
		 case 'c':
			 conffile = optarg;
			 break;
		 case 'd':
			 dflag = 1;
			 break;
		 case 'D':
			 dflag = 2;
			 break;
		 case 'f':
			 fflag = 1;
			 break;
#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
		 case 'P':
			 policy = strdup(optarg);
			 accept_rr = 1;
			 break;
#endif /*IPSEC_POLICY_IPSEC*/
#endif /*IPSEC*/
		 case 's':
			 sflag = 1;
		}
	}
	argc -= optind;
	argv += optind;
	if (argc == 0) {
		fprintf(stderr,
			"usage: rtadvd [-c conffile] [-d|D] [-f] [-s]"
			"interfaces...\n");
		exit(1);
	}

	/* set log level */
	if (dflag == 0)
		(void)setlogmask(LOG_UPTO(LOG_ERR));
	if (dflag == 1)
		(void)setlogmask(LOG_UPTO(LOG_INFO));

	/* timer initialization */
	rtadvd_timer_init();

	/* random value initialization */
	srandom((u_long)time(NULL));

	/* get iflist block from kernel */
	init_iflist();

	while (argc--)
		getconfig(*argv++);

	if (inet_pton(AF_INET6, ALLNODES, &sin6_allnodes.sin6_addr) != 1) {
		fprintf(stderr, "fatal: inet_pton failed\n");
		exit(1);
	}
	sock_open(&sock, 0, NULL);
	if (accept_rr != 0)
		sock_open(&rrsock, 1, policy);

	if (!fflag)
		daemon(1, 0);

	FD_ZERO(&fdset);
	FD_SET(sock, &fdset);
	if (accept_rr)
		FD_SET(rrsock, &fdset);
	maxfd = sock > rrsock ? sock : rrsock;
	if (sflag == 0) {
		rtsock_open();
		FD_SET(rtsock, &fdset);
		if (rtsock > maxfd)
			maxfd = rtsock;
	}

	while (1) {
		struct fd_set select_fd = fdset; /* reinitialize */

		/* timer expiration check and reset the timer */
		timeout = rtadvd_check_timer();

		syslog(LOG_DEBUG,
		       "<%s> set timer to %ld:%ld. waiting for inputs "
		       "or timeout",
		       __FUNCTION__,
		       timeout->tv_sec, timeout->tv_usec);

		if ((i = select(maxfd + 1, &select_fd,
				NULL, NULL, timeout)) < 0){
			syslog(LOG_ERR, "<%s> select: %s",
			       __FUNCTION__, strerror(errno));
			continue;
		}
		if (i == 0)	/* timeout */
			continue;
		if (sflag == 0 && FD_ISSET(rtsock, &select_fd))
			rtmsg_input();
		if (FD_ISSET(sock, &select_fd))
			rtadvd_input(sock);
		if (accept_rr && FD_ISSET(rrsock, &select_fd))
			rtadvd_input(rrsock);
	}
	exit(0);		/* NOTREACHED */
}

static void
rtmsg_input()
{
	int n, type, ifindex, plen;
	size_t len;
	char msg[2048], *next, *lim;
	u_char ifname[16];
	struct prefix *prefix;
	struct rainfo *rai;
	struct in6_addr *addr;
	char addrbuf[INET6_ADDRSTRLEN];

	n = read(rtsock, msg, 2048);
	if (dflag > 1) {
		syslog(LOG_DEBUG,
		       "<%s> received a routing message "
		       "(type = %d, len = %d)",
		       __FUNCTION__,
		       rtmsg_type(msg), n);
	}
	if (n > rtmsg_len(msg)) {
		/*
		 * This usually won't happen for messages received on
		 * an routing socket.
		 */
		if (dflag > 1)
			syslog(LOG_DEBUG,
			       "<%s> received data length is larger than"
			       "1st routing message len. multiple messages?"
			       " read %d bytes, but 1st msg len = %d",
			       __FUNCTION__, n, rtmsg_len(msg));
	}

	lim = msg + n;
	for (next = msg; next < lim; next += len) {
		next = get_next_msg(next, lim, 0, &len,
				    RTADV_TYPE2BITMASK(RTM_ADD) |
				    RTADV_TYPE2BITMASK(RTM_DELETE) |
				    RTADV_TYPE2BITMASK(RTM_NEWADDR) |
				    RTADV_TYPE2BITMASK(RTM_DELADDR) |
				    RTADV_TYPE2BITMASK(RTM_IFINFO));
		if (len == 0)
			break;
		type = rtmsg_type(next);
		switch (type) {
		case RTM_ADD:
		case RTM_DELETE:
			ifindex = get_rtm_ifindex(next);
			break;
		case RTM_NEWADDR:
		case RTM_DELADDR:
			ifindex = get_ifam_ifindex(next);
			break;
		case RTM_IFINFO:
			ifindex = get_ifm_ifindex(next);
			break;
		default:
			/* should not reach here */
			if (dflag > 1) {
				syslog(LOG_DEBUG,
				       "<%s:%d> unknown rtmsg %d on %s",
				       __FUNCTION__, __LINE__, type,
				       if_indextoname(ifindex, ifname));
			}
			return;
		}

		if ((rai = if_indextorainfo(ifindex)) == NULL) {
			if (dflag > 1) {
				syslog(LOG_DEBUG,
				       "<%s> route changed on "
				       "non advertising interface(%s)",
				       __FUNCTION__,
				       if_indextoname(ifindex, ifname));
			}
			return;
		}

		switch(type) {
		 case RTM_ADD:
			 /* init iffalgs because it may have changed */
			 iflist[ifindex]->ifm_flags =
			 	if_getflags(ifindex,
					    iflist[ifindex]->ifm_flags);

			 addr = get_addr(msg);
			 plen = get_prefixlen(msg);
			 /* sanity check for plen */
			 if (plen < 4 /* as RFC2373, prefixlen is at least 4 */
			     || plen > 127) {
				syslog(LOG_INFO, "<%s> new interface route's"
				       "plen %d is invalid for a prefix",
				       __FUNCTION__, plen);
				return;
			 }
			 prefix = find_prefix(rai, addr, plen);
			 if (prefix) {
				 if (dflag > 1) {
					 syslog(LOG_DEBUG,
						"<%s> new prefix(%s/%d) "
						"added on %s, "
						"but it was already in list",
						__FUNCTION__,
						inet_ntop(AF_INET6,
							  addr, (char *)addrbuf,
							  INET6_ADDRSTRLEN),
						plen,
						rai->ifname);
				 }
				 return;
			 }
			 make_prefix(rai, ifindex, addr, plen);
			 break;
		 case RTM_DELETE:
			 /* init ifflags because it may have changed */
			 iflist[ifindex]->ifm_flags =
			 	if_getflags(ifindex,
					    iflist[ifindex]->ifm_flags);

			 addr = get_addr(msg);
			 plen = get_prefixlen(msg);
			 /* sanity check for plen */
			 if (plen < 4 /* as RFC2373, prefixlen is at least 4 */
			     || plen > 127) {
				syslog(LOG_INFO, "<%s> deleted interface"
				       "route's"
				       "plen %d is invalid for a prefix",
				       __FUNCTION__, plen);
				return;
			 }
			 prefix = find_prefix(rai, addr, plen);
			 if (prefix == NULL) {
				 if (dflag > 1) {
					 syslog(LOG_DEBUG,
						"<%s> prefix(%s/%d) was "
						"deleted on %s, "
						"but it was not in list",
						__FUNCTION__,
						inet_ntop(AF_INET6,
							  addr, (char *)addrbuf,
							  INET6_ADDRSTRLEN),
						plen,
						rai->ifname);
				 }
				 return;
			 }
			 delete_prefix(rai, prefix);
			 break;
		case RTM_NEWADDR:
		case RTM_DELADDR:
			 /* init ifflags because it may have changed */
			 iflist[ifindex]->ifm_flags =
			 	if_getflags(ifindex,
					    iflist[ifindex]->ifm_flags);
			 break;
		case RTM_IFINFO:
			 iflist[ifindex]->ifm_flags = get_ifm_flags(next);
			 break;
		default:
			/* should not reach here */
			if (dflag > 1) {
				syslog(LOG_DEBUG,
				       "<%s:%d> unknown rtmsg %d on %s",
				       __FUNCTION__, __LINE__, type,
				       if_indextoname(ifindex, ifname));
			}
			return;
		}
	}

	return;
}

void
rtadvd_input(skt)
{
	int i;
	int *hlimp = NULL;
	struct icmp6_hdr *icp;
	int ifindex = 0;
	struct cmsghdr *cm;
	struct in6_pktinfo *pi = NULL;
	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
	struct in6_addr dst = in6addr_any;

	/*
	 * Get message. We reset msg_controllen since the field could
	 * be modified if we had received a message before setting
	 * receive options.
	 */
	rcvmhdr.msg_controllen = sizeof(rcvcmsgbuf);
	if ((i = recvmsg(skt, &rcvmhdr, 0)) < 0)
		return;

	/* extract optional information via Advanced API */
	for (cm = (struct cmsghdr *)CMSG_FIRSTHDR(&rcvmhdr);
	     cm;
	     cm = (struct cmsghdr *)CMSG_NXTHDR(&rcvmhdr, cm)) {
		if (cm->cmsg_level == IPPROTO_IPV6 &&
		    cm->cmsg_type == IPV6_PKTINFO &&
		    cm->cmsg_len == CMSG_LEN(sizeof(struct in6_pktinfo))) {
			pi = (struct in6_pktinfo *)(CMSG_DATA(cm));
			ifindex = pi->ipi6_ifindex;
			dst = pi->ipi6_addr;
		}
		if (cm->cmsg_level == IPPROTO_IPV6 &&
		    cm->cmsg_type == IPV6_HOPLIMIT &&
		    cm->cmsg_len == CMSG_LEN(sizeof(int)))
			hlimp = (int *)CMSG_DATA(cm);
	}
	if (ifindex == 0) {
		syslog(LOG_ERR,
		       "<%s> failed to get receiving interface",
		       __FUNCTION__);
		return;
	}
	if (hlimp == NULL) {
		syslog(LOG_ERR,
		       "<%s> failed to get receiving hop limit",
		       __FUNCTION__);
		return;
	}

	if (i < sizeof(struct icmp6_hdr)) {
		syslog(LOG_ERR,
		       "<%s> packet size(%d) is too short",
		       __FUNCTION__, i);
		return;
	}

	icp = (struct icmp6_hdr *)rcvmhdr.msg_iov[0].iov_base;

	switch(icp->icmp6_type) {
	 case ND_ROUTER_SOLICIT:
		 /* hop limit verification - RFC-2461 6.1.1 */
		 if (*hlimp != 255) {
			 syslog(LOG_NOTICE,
				"<%s> invalid hop limit(%d) "
				"received from %s on %s",
				__FUNCTION__, *hlimp,
				inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
					  INET6_ADDRSTRLEN),
				if_indextoname(pi->ipi6_ifindex, ifnamebuf));
			 return;
		 }
		 rs_input(i, (struct nd_router_solicit *)icp, pi, &from);
		 break;
	 case ND_ROUTER_ADVERT:
		 /* hop limit verification - RFC-2461 6.1.1 */
		 if (*hlimp != 255) {
			 syslog(LOG_NOTICE,
				"<%s> invalid hop limit(%d) "
				"received from %s on %s",
				__FUNCTION__, *hlimp,
				inet_ntop(AF_INET6, &from.sin6_addr, ntopbuf,
					  INET6_ADDRSTRLEN),
				if_indextoname(pi->ipi6_ifindex, ifnamebuf));
			 return;
		 }
		 ra_input(i, (struct nd_router_advert *)icp, pi, &from);
		 break;
	 case ICMP6_ROUTER_RENUMBERING:
		 if (accept_rr == 0) {
			 syslog(LOG_ERR,
				"<%s> received a router renumbering "
				"message, but not allowed to be accepted",
				__FUNCTION__);
			 break;
		 }
		 rr_input(i, (struct icmp6_router_renum *)icp, pi, &from,
			  &dst);
		 break;
	 default:
		 /*
		  * Note that this case is POSSIBLE, especially just
		  * after invocation of the daemon. This is because we
		  * could receive message after opening the socket and
		  * before setting ICMP6 type filter(see sock_open()).
		  */
		 syslog(LOG_ERR,
			"<%s> invalid icmp type(%d)",
			__FUNCTION__, icp->icmp6_type);
		 return;
	}

	return;
}

static void
rs_input(int len, struct nd_router_solicit *rs,
	 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
{
	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
	union nd_opts ndopts;
	struct rainfo *ra;

	syslog(LOG_DEBUG,
	       "<%s> RS received from %s on %s",
	       __FUNCTION__,
	       inet_ntop(AF_INET6, &from->sin6_addr,
			 ntopbuf, INET6_ADDRSTRLEN),
	       if_indextoname(pi->ipi6_ifindex, ifnamebuf));

	/* ND option check */
	memset(&ndopts, 0, sizeof(ndopts));
	if (nd6_options((struct nd_opt_hdr *)(rs + 1),
			len - sizeof(struct nd_router_solicit),
			 &ndopts, NDOPT_FLAG_SRCLINKADDR)) {
		syslog(LOG_DEBUG,
		       "<%s> ND option check failed for an RS from %s on %s",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
		return;
	}

	/*
	 * If the IP source address is the unspecified address, there
	 * must be no source link-layer address option in the message.
	 * (RFC-2461 6.1.1)
	 */
	if (IN6_IS_ADDR_UNSPECIFIED(&from->sin6_addr) &&
	    ndopts.nd_opts_src_lladdr) {
		syslog(LOG_ERR,
		       "<%s> RS from unspecified src on %s has a link-layer"
		       " address option",
		       __FUNCTION__,
		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
		goto done;
	}

	ra = ralist;
	while (ra != NULL) {
		if (pi->ipi6_ifindex == ra->ifindex)
			break;
		ra = ra->next;
	}
	if (ra == NULL) {
		syslog(LOG_INFO,
		       "<%s> RS received on non advertising interface(%s)",
		       __FUNCTION__,
		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
		goto done;
	}

	/*
	 * Decide whether to send RA according to the rate-limit
	 * consideration.
	 */
	{
		long delay;	/* must not be greater than 1000000 */
		struct timeval interval, now, min_delay, tm_tmp, *rest;

		/*
		 * If there is already a waiting RS packet, don't
		 * update the timer.
		 */
		if (ra->waiting++)
			goto done;

		/*
		 * Compute a random delay. If the computed value
		 * corresponds to a time later than the time the next
		 * multicast RA is scheduled to be sent, ignore the random
		 * delay and send the advertisement at the
		 * already-scheduled time. RFC-2461 6.2.6
		 */
		delay = random() % MAX_RA_DELAY_TIME;
		interval.tv_sec = 0;
		interval.tv_usec = delay;
		rest = rtadvd_timer_rest(ra->timer);
		if (TIMEVAL_LT(*rest, interval)) {
			syslog(LOG_DEBUG,
			       "<%s> random delay is larger than "
			       "the rest of normal timer",
			       __FUNCTION__);
			interval = *rest;
		}

		/*
		 * If we sent a multicast Router Advertisement within
		 * the last MIN_DELAY_BETWEEN_RAS seconds, schedule
		 * the advertisement to be sent at a time corresponding to
		 * MIN_DELAY_BETWEEN_RAS plus the random value after the
		 * previous advertisement was sent.
		 */
		gettimeofday(&now, NULL);
		TIMEVAL_SUB(&now, &ra->lastsent, &tm_tmp);
		min_delay.tv_sec = MIN_DELAY_BETWEEN_RAS;
		min_delay.tv_usec = 0;
		if (TIMEVAL_LT(tm_tmp, min_delay)) {
			TIMEVAL_SUB(&min_delay, &tm_tmp, &min_delay);
			TIMEVAL_ADD(&min_delay, &interval, &interval);
		}
		rtadvd_set_timer(&interval, ra->timer);
			goto done;
	}

  done:
	free_ndopts(&ndopts);
	return;
}

static void
ra_input(int len, struct nd_router_advert *ra,
	 struct in6_pktinfo *pi, struct sockaddr_in6 *from)
{
	struct rainfo *rai;
	u_char ntopbuf[INET6_ADDRSTRLEN], ifnamebuf[IFNAMSIZ];
	union nd_opts ndopts;
	char *on_off[] = {"OFF", "ON"};
	u_int32_t reachabletime, retranstimer, mtu;

	syslog(LOG_DEBUG,
	       "<%s> RA received from %s on %s",
	       __FUNCTION__,
	       inet_ntop(AF_INET6, &from->sin6_addr,
			 ntopbuf, INET6_ADDRSTRLEN),
	       if_indextoname(pi->ipi6_ifindex, ifnamebuf));

	/* ND option check */
	memset(&ndopts, 0, sizeof(ndopts));
	if (nd6_options((struct nd_opt_hdr *)(ra + 1),
			len - sizeof(struct nd_router_advert),
			 &ndopts,
			NDOPT_FLAG_PREFIXINFO | NDOPT_FLAG_MTU)) {
		syslog(LOG_ERR,
		       "<%s> ND option check failed for an RA from %s on %s",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
		return;
	}

	/*
	 * RA consistency check according to RFC-2461 6.2.7
	 */
	if ((rai = if_indextorainfo(pi->ipi6_ifindex)) == 0) {
		syslog(LOG_INFO,
		       "<%s> received RA from %s on non-advertising"
		       " interface(%s)",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       if_indextoname(pi->ipi6_ifindex, ifnamebuf));
		goto done;
	}
	/* Cur Hop Limit value */
	if (ra->nd_ra_curhoplimit && rai->hoplimit &&
	    ra->nd_ra_curhoplimit != rai->hoplimit) {
		syslog(LOG_WARNING,
		       "<%s> CurHopLimit inconsistent on %s:"
		       " %d from %s, %d from us",
		       __FUNCTION__,
		       rai->ifname,
		       ra->nd_ra_curhoplimit,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       rai->hoplimit);
	}
	/* M flag */
	if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_MANAGED) !=
	    rai->managedflg) {
		syslog(LOG_WARNING,
		       "<%s> M flag inconsistent on %s:"
		       " %s from %s, %s from us",
		       __FUNCTION__,
		       rai->ifname,
		       on_off[!rai->managedflg],
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       on_off[rai->managedflg]);
	}
	/* O flag */
	if ((ra->nd_ra_flags_reserved & ND_RA_FLAG_OTHER) !=
	    rai->otherflg) {
		syslog(LOG_WARNING,
		       "<%s> O flag inconsistent on %s:"
		       " %s from %s, %s from us",
		       __FUNCTION__,
		       rai->ifname,
		       on_off[!rai->otherflg],
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       on_off[rai->otherflg]);
	}
	/* Reachable Time */
	reachabletime = ntohl(ra->nd_ra_reachable);
	if (reachabletime && rai->reachabletime &&
	    reachabletime != rai->reachabletime) {
		syslog(LOG_WARNING,
		       "<%s> ReachableTime inconsistent on %s:"
		       " %d from %s, %d from us",
		       __FUNCTION__,
		       rai->ifname,
		       reachabletime,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       rai->reachabletime);
	}
	/* Retrans Timer */
	retranstimer = ntohl(ra->nd_ra_retransmit);
	if (retranstimer && rai->retranstimer &&
	    retranstimer != rai->retranstimer) {
		syslog(LOG_WARNING,
		       "<%s> RetranceTimer inconsistent on %s:"
		       " %d from %s, %d from us",
		       __FUNCTION__,
		       rai->ifname,
		       retranstimer,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       rai->retranstimer);
	}
	/* Values in the MTU options */
	if (ndopts.nd_opts_mtu) {
		mtu = ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
		if (mtu && rai->linkmtu && mtu != rai->linkmtu) {
			syslog(LOG_WARNING,
			       "<%s> MTU option value inconsistent on %s:"
			       " %d from %s, %d from us",
			       __FUNCTION__,
			       rai->ifname, mtu,
			       inet_ntop(AF_INET6, &from->sin6_addr,
					 ntopbuf, INET6_ADDRSTRLEN),
			       rai->linkmtu);
		}
	}
	/* Preferred and Valid Lifetimes for prefixes */
	{
		struct nd_optlist *optp = ndopts.nd_opts_list;

		if (ndopts.nd_opts_pi)
			prefix_check(ndopts.nd_opts_pi, rai, from);
		while (optp) {
			prefix_check((struct nd_opt_prefix_info *)optp->opt,
				     rai, from);
			optp = optp->next;
		}
	}

  done:
	free_ndopts(&ndopts);
	return;
}

static void
prefix_check(struct nd_opt_prefix_info *pinfo,
	     struct rainfo *rai, struct sockaddr_in6 *from)
{
	u_int32_t preferred_time, valid_time;
	struct prefix *pp;
	u_char ntopbuf[INET6_ADDRSTRLEN], prefixbuf[INET6_ADDRSTRLEN];

	/*
	 * log if the adveritsed prefix has link-local scope(sanity check?)
	 */
	if (IN6_IS_ADDR_LINKLOCAL(&pinfo->nd_opt_pi_prefix)) {
		syslog(LOG_INFO,
		       "<%s> link-local prefix %s/%d is advertised "
		       "from %s on %s",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
				 prefixbuf, INET6_ADDRSTRLEN),
		       pinfo->nd_opt_pi_prefix_len,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       rai->ifname);
	}

	if ((pp = find_prefix(rai, &pinfo->nd_opt_pi_prefix,
			      pinfo->nd_opt_pi_prefix_len)) == NULL) {
		syslog(LOG_INFO,
		       "<%s> prefix %s/%d from %s on %s is not in our list",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
				 prefixbuf, INET6_ADDRSTRLEN),
		       pinfo->nd_opt_pi_prefix_len,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       rai->ifname);
		return;
	}

	preferred_time = ntohl(pinfo->nd_opt_pi_preferred_time);
	if (preferred_time != pp->preflifetime)
		syslog(LOG_WARNING,
		       "<%s> prefeerred lifetime for %s/%d"
		       " inconsistent on %s:"
		       " %d from %s, %d from us",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
				 prefixbuf, INET6_ADDRSTRLEN),
		       pinfo->nd_opt_pi_prefix_len,
		       rai->ifname, preferred_time,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       pp->preflifetime);

	valid_time = ntohl(pinfo->nd_opt_pi_valid_time);
	if (valid_time != pp->validlifetime)
		syslog(LOG_WARNING,
		       "<%s> valid lifetime for %s/%d"
		       " inconsistent on %s:"
		       " %d from %s, %d from us",
		       __FUNCTION__,
		       inet_ntop(AF_INET6, &pinfo->nd_opt_pi_prefix,
				 prefixbuf, INET6_ADDRSTRLEN),
		       pinfo->nd_opt_pi_prefix_len,
		       rai->ifname, valid_time,
		       inet_ntop(AF_INET6, &from->sin6_addr,
				 ntopbuf, INET6_ADDRSTRLEN),
		       pp->validlifetime);
}

struct prefix *
find_prefix(struct rainfo *rai, struct in6_addr *prefix, int plen)
{
	struct prefix *pp;
	int bytelen, bitlen;

	for (pp = rai->prefix.next; pp != &rai->prefix; pp = pp->next) {
		if (plen != pp->prefixlen)
			continue;
		bytelen = plen / 8;
		bitlen = plen % 8;
		if (memcmp((void *)prefix, (void *)&pp->prefix, bytelen))
			continue;
		if (prefix->s6_addr[bytelen] >> (8 - bitlen) ==
		    pp->prefix.s6_addr[bytelen] >> (8 - bitlen))
			return(pp);
	}

	return(NULL);
}

static int
nd6_options(struct nd_opt_hdr *hdr, int limit,
	    union nd_opts *ndopts, u_int32_t optflags)
{
	int optlen = 0;

	for (; limit > 0; limit -= optlen) {
		hdr = (struct nd_opt_hdr *)((caddr_t)hdr + optlen);
		optlen = hdr->nd_opt_len << 3;
		if (hdr->nd_opt_len == 0) {
			syslog(LOG_ERR,
			       "<%s> bad ND option length(0) (type = %d)",
			       __FUNCTION__, hdr->nd_opt_type);
			goto bad;
		}

		if (hdr->nd_opt_type > ND_OPT_MTU) {
			syslog(LOG_INFO,
			       "<%s> unknown ND option(type %d)",
			       __FUNCTION__,
			       hdr->nd_opt_type);
			continue;
		}

		if ((ndopt_flags[hdr->nd_opt_type] & optflags) == 0) {
			syslog(LOG_INFO,
			       "<%s> unexpected ND option(type %d)",
			       __FUNCTION__,
			       hdr->nd_opt_type);
			continue;
		}

		switch(hdr->nd_opt_type) {
		 case ND_OPT_SOURCE_LINKADDR:
		 case ND_OPT_TARGET_LINKADDR:
		 case ND_OPT_REDIRECTED_HEADER:
		 case ND_OPT_MTU:
			 if (ndopts->nd_opt_array[hdr->nd_opt_type]) {
				 syslog(LOG_INFO,
					"<%s> duplicated ND option"
					" (type = %d)",
					__FUNCTION__,
					hdr->nd_opt_type);
			 }
			 ndopts->nd_opt_array[hdr->nd_opt_type] = hdr;
			 break;
		 case ND_OPT_PREFIX_INFORMATION:
		 {
			 struct nd_optlist *pfxlist;

			 if (ndopts->nd_opts_pi == 0) {
				 ndopts->nd_opts_pi =
					 (struct nd_opt_prefix_info *)hdr;
				 continue;
			 }
			 if ((pfxlist = malloc(sizeof(*pfxlist))) == NULL) {
				 syslog(LOG_ERR,
					"<%s> can't allocate memory",
					__FUNCTION__);
				 goto bad;
			 }
			 pfxlist->next = ndopts->nd_opts_list;
			 pfxlist->opt = hdr;
			 ndopts->nd_opts_list = pfxlist;

			 break;
		 }
		 default:	/* impossible */
			 break;
		}
	}

	return(0);

  bad:
	free_ndopts(ndopts);

	return(-1);
}

static void
free_ndopts(union nd_opts *ndopts)
{
	struct nd_optlist *opt = ndopts->nd_opts_list, *next;

	while(opt) {
		next = opt->next;
		free(opt);
		opt = next;
	}
}

void
sock_open(int *sockp, int is_rr, char *policy)
{
	struct icmp6_filter filt;
	struct ipv6_mreq mreq;
	struct rainfo *ra = ralist;
	int on;
	char *rtr_str;
	/* XXX: should be max MTU attached to the node */
	static u_char answer[1500];
	static u_char sndcmsgbuf[CMSG_SPACE(sizeof(struct in6_pktinfo)) +
				CMSG_SPACE(sizeof(int))];

	if ((*sockp = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) < 0) {
		syslog(LOG_ERR, "<%s> socket: %s", __FUNCTION__,
		       strerror(errno));
		exit(1);
	}

	/* specify to tell receiving interface */
	on = 1;
	if (setsockopt(*sockp, IPPROTO_IPV6, IPV6_PKTINFO, &on,
		       sizeof(on)) < 0) {
		syslog(LOG_ERR, "<%s> IPV6_PKTINFO: %s",
		       __FUNCTION__, strerror(errno));
		exit(1);
	}

	on = 1;
	/* specify to tell value of hoplimit field of received IP6 hdr */
	if (setsockopt(*sockp, IPPROTO_IPV6, IPV6_HOPLIMIT, &on,
		       sizeof(on)) < 0) {
		syslog(LOG_ERR, "<%s> IPV6_HOPLIMIT: %s",
		       __FUNCTION__, strerror(errno));
		exit(1);
	}

	ICMP6_FILTER_SETBLOCKALL(&filt);
	if (is_rr)
		ICMP6_FILTER_SETPASS(ICMP6_ROUTER_RENUMBERING, &filt);
	else {
		ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filt);
		ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
	}
	if (setsockopt(*sockp, IPPROTO_ICMPV6, ICMP6_FILTER, &filt,
		       sizeof(filt)) < 0) {
		syslog(LOG_ERR, "<%s> IICMP6_FILTER: %s",
		       __FUNCTION__, strerror(errno));
		exit(1);
	}


#ifdef IPSEC
#ifdef IPSEC_POLICY_IPSEC
	if (is_rr && policy != NULL) {
		char *buf;

		buf = ipsec_set_policy(policy, strlen(policy));
		if (buf == NULL)
			errx(EX_CONFIG, ipsec_strerror());
		if (setsockopt(*sockp, IPPROTO_IPV6, IPV6_IPSEC_POLICY,
			       buf, ipsec_get_policylen(buf)) < 0)
			err(EX_CONFIG, "ipsec policy cannot be configured");
		free(buf);
	}
#endif /*IPSEC_POLICY_IPSEC*/
#endif /*IPSEC*/

	/*
	 * join all routers multicast address on each advertising interface.
	 */
	rtr_str = is_rr ? ALLSITEROUTERS : ALLROUTERS;
	if (inet_pton(AF_INET6, rtr_str, &mreq.ipv6mr_multiaddr.s6_addr)
	    != 1) {
		syslog(LOG_ERR, "<%s> inet_pton for %s failed(library bug?)",
		       __FUNCTION__, rtr_str);
		exit(1);
	}
	while(ra) {
		mreq.ipv6mr_interface = ra->ifindex;
		if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq,
			       sizeof(mreq)) < 0) {
			syslog(LOG_ERR, "<%s> IPV6_JOIN_GROUP for %s on"
			       "%s: %s", __FUNCTION__,
			       rtr_str, ra->ifname, strerror(errno));
			exit(1);
		}
		ra = ra->next;
	}
	if (is_rr) /* msghdrs should have been alreadey initialized. */
		return;

	/* initialize msghdr for receiving packets */
	rcviov[0].iov_base = (caddr_t)answer;
	rcviov[0].iov_len = sizeof(answer);
	rcvmhdr.msg_name = (caddr_t)&from;
	rcvmhdr.msg_namelen = sizeof(from);
	rcvmhdr.msg_iov = rcviov;
	rcvmhdr.msg_iovlen = 1;
	rcvmhdr.msg_control = (caddr_t) rcvcmsgbuf;
	rcvmhdr.msg_controllen = sizeof(rcvcmsgbuf);

	/* initialize msghdr for sending packets */
	sndmhdr.msg_namelen = sizeof(struct sockaddr_in6);
	sndmhdr.msg_iov = sndiov;
	sndmhdr.msg_iovlen = 1;
	sndmhdr.msg_control = (caddr_t)sndcmsgbuf;
	sndmhdr.msg_controllen = sizeof(sndcmsgbuf);

	return;
}

/* open a routing socket to watch the routing table */
static void
rtsock_open()
{
	if ((rtsock = socket(PF_ROUTE, SOCK_RAW, 0)) < 0) {
		syslog(LOG_ERR,
		       "<%s> socket: %s", __FUNCTION__, strerror(errno));
		exit(1);
	}
}

static struct rainfo *
if_indextorainfo(int index)
{
	struct rainfo *rai = ralist;

	for (rai = ralist; rai; rai = rai->next) {
		if (rai->ifindex == index)
			return(rai);
	}

	return(NULL);		/* search failed */
}

static void
ra_output(rainfo)
struct rainfo *rainfo;
{
	int i;

	struct cmsghdr *cm;
	struct in6_pktinfo *pi;

	sndmhdr.msg_name = (caddr_t)&sin6_allnodes;
	sndmhdr.msg_iov[0].iov_base = (caddr_t)rainfo->ra_data;
	sndmhdr.msg_iov[0].iov_len = rainfo->ra_datalen;

	cm = CMSG_FIRSTHDR(&sndmhdr);
	/* specify the outgoing interface */
	cm->cmsg_level = IPPROTO_IPV6;
	cm->cmsg_type = IPV6_PKTINFO;
	cm->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
	pi = (struct in6_pktinfo *)CMSG_DATA(cm);
	memset(&pi->ipi6_addr, 0, sizeof(pi->ipi6_addr));	/*XXX*/
	pi->ipi6_ifindex = rainfo->ifindex;

	/* specify the hop limit of the packet */
	{
		int hoplimit = 255;

		cm = CMSG_NXTHDR(&sndmhdr, cm);
		cm->cmsg_level = IPPROTO_IPV6;
		cm->cmsg_type = IPV6_HOPLIMIT;
		cm->cmsg_len = CMSG_LEN(sizeof(int));
		memcpy(CMSG_DATA(cm), &hoplimit, sizeof(int));
	}

	syslog(LOG_DEBUG,
	       "<%s> send RA on %s, # of waitings = %d",
	       __FUNCTION__, rainfo->ifname, rainfo->waiting);

	i = sendmsg(sock, &sndmhdr, 0);

	if (i < 0 || i != rainfo->ra_datalen)  {
		if (i < 0) {
			syslog(LOG_ERR, "<%s> sendmsg: %s",
			       __FUNCTION__, strerror(errno));
		}
	}

	/* update counter */
	if (rainfo->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS)
		rainfo->initcounter++;

	/* update timestamp */
	gettimeofday(&rainfo->lastsent, NULL);

	/* reset waiting conter */
	rainfo->waiting = 0;
}

/* process RA timer */
void
ra_timeout(void *data)
{
	struct rainfo *rai = (struct rainfo *)data;

#ifdef notyet
	/* if necessary, reconstruct the packet. */
#endif

	syslog(LOG_DEBUG,
	       "<%s> RA timer on %s is expired",
	       __FUNCTION__, rai->ifname);

	if (iflist[rai->ifindex]->ifm_flags & IFF_UP)
		ra_output(rai);
	else
		syslog(LOG_DEBUG, "<%s> %s is not up, skip sending RA",
		       __FUNCTION__, rai->ifname);
}

/* update RA timer */
void
ra_timer_update(void *data, struct timeval *tm)
{
	struct rainfo *rai = (struct rainfo *)data;
	long interval;

	/*
	 * Whenever a multicast advertisement is sent from an interface,
	 * the timer is reset to a uniformly-distributed random value
	 * between the interface's configured MinRtrAdvInterval and
	 * MaxRtrAdvInterval(discovery-v2-02 6.2.4).
	 */
	interval = rai->mininterval;
	interval += random() % (rai->maxinterval - rai->mininterval);

	/*
	 * For the first few advertisements (up to
	 * MAX_INITIAL_RTR_ADVERTISEMENTS), if the randomly chosen interval
	 * is greater than MAX_INITIAL_RTR_ADVERT_INTERVAL, the timer
	 * SHOULD be set to MAX_INITIAL_RTR_ADVERT_INTERVAL instead.
	 * (RFC-2461 6.2.4)
	 */
	if (rai->initcounter < MAX_INITIAL_RTR_ADVERTISEMENTS &&
	    interval > MAX_INITIAL_RTR_ADVERT_INTERVAL)
		interval = MAX_INITIAL_RTR_ADVERT_INTERVAL;

	tm->tv_sec = interval;
	tm->tv_usec = 0;

	syslog(LOG_DEBUG,
	       "<%s> RA timer on %s is set to %ld:%ld",
	       __FUNCTION__, rai->ifname, tm->tv_sec, tm->tv_usec);

	return;
}
OpenPOWER on IntegriCloud