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- changed the logic in nd6_is_addr_neighbor(); check on-link prefixes

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(not interface addresses) to see if a given address is on-link.
- skip offlink prefixes in neighbor determination in nd6_is_addr_neighbor.
- in nd6_is_addr_neighbor, regarded every address as on-link when the
  default router list is empty.  otherwise, we'd not be able make a neighbor
  cache for the address.
  this algorithm is applied to hosts only.
- in nd6_is_addr_neighbor, check if the default interface is equal to
  the interface in question in addition to check if the default router
  list is empty.

Obtained from:	KAME
This commit is contained in:
Hajimu UMEMOTO 2003-12-08 11:59:21 +00:00
parent 6d5957433e
commit 4208ea1439
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=123296
1 changed files with 23 additions and 17 deletions
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40
sys/netinet6/nd6.c
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@ -877,16 +877,13 @@ nd6_is_addr_neighbor(addr, ifp)
struct sockaddr_in6 *addr;
struct ifnet *ifp;
{
struct ifaddr *ifa;
int i;
#define IFADDR6(a) ((((struct in6_ifaddr *)(a))->ia_addr).sin6_addr)
#define IFMASK6(a) ((((struct in6_ifaddr *)(a))->ia_prefixmask).sin6_addr)
struct nd_prefix *pr;
/*
* A link-local address is always a neighbor.
* XXX: we should use the sin6_scope_id field rather than the embedded
* interface index.
* XXX: a link does not necessarily specify a single interface.
*/
if (IN6_IS_ADDR_LINKLOCAL(&addr->sin6_addr) &&
ntohs(*(u_int16_t *)&addr->sin6_addr.s6_addr[2]) == ifp->if_index)
@ -895,18 +892,29 @@ nd6_is_addr_neighbor(addr, ifp)
/*
* If the address matches one of our addresses,
* it should be a neighbor.
* If the address matches one of our on-link prefixes, it should be a
* neighbor.
*/
for (ifa = ifp->if_addrlist.tqh_first; ifa;
ifa = ifa->ifa_list.tqe_next) {
if (ifa->ifa_addr->sa_family != AF_INET6)
next: continue;
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
if (pr->ndpr_ifp != ifp)
continue;
for (i = 0; i < 4; i++) {
if ((IFADDR6(ifa).s6_addr32[i] ^
addr->sin6_addr.s6_addr32[i]) &
IFMASK6(ifa).s6_addr32[i])
goto next;
}
if (!(pr->ndpr_stateflags & NDPRF_ONLINK))
continue;
if (IN6_ARE_MASKED_ADDR_EQUAL(&pr->ndpr_prefix.sin6_addr,
&addr->sin6_addr, &pr->ndpr_mask))
return (1);
}
/*
* If the default router list is empty, all addresses are regarded
* as on-link, and thus, as a neighbor.
* XXX: we restrict the condition to hosts, because routers usually do
* not have the "default router list".
*/
if (!ip6_forwarding && TAILQ_FIRST(&nd_defrouter) == NULL &&
nd6_defifindex == ifp->if_index) {
return (1);
}
@ -918,8 +926,6 @@ nd6_is_addr_neighbor(addr, ifp)
return (1);
return (0);
#undef IFADDR6
#undef IFMASK6
}
/*