Date: Mon, 22 May 2006 18:40:48 +0900 From: JINMEI Tatuya / =?ISO-2022-JP?B?GyRCP0BMQEMjOkgbKEI=?= <jinmei@isl.rdc.toshiba.co.jp> To: Ed Schouten <ed@fxq.nl>, "Bruce A. Mah" <bmah@freebsd.org> Cc: FreeBSD Net <freebsd-net@freebsd.org> Subject: Re: nd6_lookup prints bogus messages with point to point devices Message-ID: <y7vk68eqtwf.wl%jinmei@isl.rdc.toshiba.co.jp> In-Reply-To: <y7v7j4k623s.wl%jinmei@isl.rdc.toshiba.co.jp> References: <20060506172742.GM15353@hoeg.nl> <445EC341.60406@freebsd.org> <20060508065841.GN15353@hoeg.nl> <y7v7j4k623s.wl%jinmei@isl.rdc.toshiba.co.jp>
next in thread | previous in thread | raw e-mail | index | archive | help
>>>>> On Thu, 18 May 2006 01:35:35 +0900,
>>>>> JINMEI Tatuya <jinmei@isl.rdc.toshiba.co.jp> said:
>> I'm seeing the messages on the machine in Eindhoven (running RELENG_6
>> from a few days/weeks ago), but they also show up on my HEAD machine at
>> home. Below is the output of `ifconfig gif0` on my machine at home:
>> | gif0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1280
>> | tunnel inet 83.181.147.170 --> 193.109.122.244
>> | inet6 fe80::202:a5ff:fe58:4927%gif0 prefixlen 64 scopeid 0x7
>> | inet6 2001:7b8:310::1 --> 2001:7b8:2ff:a4::1 prefixlen 128
>> As far as I know, the latest FreeBSD releases show an error message when
>> assigning an address with a non-128 prefixlen.
> Sorry for not responding sooner, but I think I've figured out the
> problem. I'm now testing a local patch to this problem, and will
> report the details once I confirm the behavior.
Could you try the patch attached below? It's for 6.1-RELEASE, but I
guess it's pretty easy to apply to CURRENT.
The essential reason of this problem is that the latest kernel regards
the destination address of a point-to-point interface as a "neighbor"
wrt Neighbor Discovery while a neighbor cache entry is not created on
configuring the interface with the addresses. I believe it makes
sense to treat the destination address as a neighbor, so the fix is to
make sure that the cache entry is created when the interface is
configured.
Thanks,
JINMEI, Tatuya
Communication Platform Lab.
Corporate R&D Center, Toshiba Corp.
jinmei@isl.rdc.toshiba.co.jp
Index: in6.c
===================================================================
RCS file: /home/ncvs/src/sys/netinet6/in6.c,v
retrieving revision 1.51.2.8
diff -u -r1.51.2.8 in6.c
--- in6.c 9 Mar 2006 11:59:03 -0000 1.51.2.8
+++ in6.c 18 May 2006 05:27:07 -0000
@@ -1720,20 +1720,55 @@
/* we could do in(6)_socktrim here, but just omit it at this moment. */
+ if (newhost && nd6_need_cache(ifp) != 0) {
+ /* set the rtrequest function to create llinfo */
+ ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
+ }
+
/*
* Special case:
* If a new destination address is specified for a point-to-point
* interface, install a route to the destination as an interface
- * direct route.
+ * direct route. In addition, if the link is expected to have neighbor
+ * cache entries, specify RTF_LLINFO so that a cache entry for the
+ * destination address will be created.
+ * created
* XXX: the logic below rejects assigning multiple addresses on a p2p
- * interface that share a same destination.
+ * interface that share the same destination.
*/
plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
if (!(ia->ia_flags & IFA_ROUTE) && plen == 128 &&
ia->ia_dstaddr.sin6_family == AF_INET6) {
- if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD,
- RTF_UP | RTF_HOST)) != 0)
+ int rtflags = RTF_UP | RTF_HOST;
+ struct rtentry *rt = NULL, **rtp = NULL;
+
+ if (nd6_need_cache(ifp) != 0) {
+ rtflags |= RTF_LLINFO;
+ rtp = &rt;
+ }
+
+ error = rtrequest(RTM_ADD, (struct sockaddr *)&ia->ia_dstaddr,
+ (struct sockaddr *)&ia->ia_addr,
+ (struct sockaddr *)&ia->ia_prefixmask,
+ ia->ia_flags | rtflags, rtp);
+ if (error != 0)
return (error);
+ if (rt != NULL) {
+ struct llinfo_nd6 *ln;
+
+ RT_LOCK(rt);
+ ln = (struct llinfo_nd6 *)rt->rt_llinfo;
+ if (ln != NULL) {
+ /*
+ * Set the state to STALE because we don't
+ * have to perform address resolution on this
+ * link.
+ */
+ ln->ln_state = ND6_LLINFO_STALE;
+ }
+ RT_REMREF(rt);
+ RT_UNLOCK(rt);
+ }
ia->ia_flags |= IFA_ROUTE;
}
if (plen < 128) {
@@ -1744,11 +1779,8 @@
}
/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
- if (newhost) {
- /* set the rtrequest function to create llinfo */
- ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
+ if (newhost)
in6_ifaddloop(&(ia->ia_ifa));
- }
return (error);
}
Index: nd6.c
===================================================================
RCS file: /home/ncvs/src/sys/netinet6/nd6.c,v
retrieving revision 1.48.2.12
diff -u -r1.48.2.12 nd6.c
--- nd6.c 29 Mar 2006 21:05:11 -0000 1.48.2.12
+++ nd6.c 18 May 2006 05:27:08 -0000
@@ -512,6 +512,19 @@
ln->ln_asked++;
nd6_llinfo_settimer(ln, (long)ndi->retrans * hz / 1000);
nd6_ns_output(ifp, dst, dst, ln, 0);
+ } else if (rt->rt_ifa != NULL &&
+ rt->rt_ifa->ifa_addr->sa_family == AF_INET6 &&
+ (((struct in6_ifaddr *)rt->rt_ifa)->ia_flags & IFA_ROUTE)) {
+ /*
+ * This is an unreachable neighbor whose address is
+ * specified as the destination of a p2p interface
+ * (see in6_ifinit()). We should not free the entry
+ * since this is sort of a "static" entry generated
+ * via interface address configuration.
+ */
+ ln->ln_asked = 0;
+ ln->ln_expire = 0; /* make it permanent */
+ ln->ln_state = ND6_LLINFO_STALE;
} else {
(void)nd6_free(rt, 0);
ln = NULL;
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?y7vk68eqtwf.wl%jinmei>