diff options
| -rw-r--r-- | net/ipv6/route.c | 90 |
1 files changed, 47 insertions, 43 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index f587a0e..e16c982 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1144,59 +1144,63 @@ static int ip6_route_del(struct in6_rtmsg *rtmsg, struct nlmsghdr *nlh, void *_r void rt6_redirect(struct in6_addr *dest, struct in6_addr *saddr, struct neighbour *neigh, u8 *lladdr, int on_link) { - struct rt6_info *rt, *nrt; - - /* Locate old route to this destination. */ - rt = rt6_lookup(dest, NULL, neigh->dev->ifindex, 1); - - if (rt == NULL) - return; - - if (neigh->dev != rt->rt6i_dev) - goto out; + struct rt6_info *rt, *nrt = NULL; + int strict; + struct fib6_node *fn; /* - * Current route is on-link; redirect is always invalid. - * - * Seems, previous statement is not true. It could - * be node, which looks for us as on-link (f.e. proxy ndisc) - * But then router serving it might decide, that we should - * know truth 8)8) --ANK (980726). + * Get the "current" route for this destination and + * check if the redirect has come from approriate router. + * + * RFC 2461 specifies that redirects should only be + * accepted if they come from the nexthop to the target. + * Due to the way the routes are chosen, this notion + * is a bit fuzzy and one might need to check all possible + * routes. */ - if (!(rt->rt6i_flags&RTF_GATEWAY)) - goto out; + strict = ipv6_addr_type(dest) & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL); - /* - * RFC 2461 specifies that redirects should only be - * accepted if they come from the nexthop to the target. - * Due to the way default routers are chosen, this notion - * is a bit fuzzy and one might need to check all default - * routers. - */ - if (!ipv6_addr_equal(saddr, &rt->rt6i_gateway)) { - if (rt->rt6i_flags & RTF_DEFAULT) { - struct rt6_info *rt1; - - read_lock(&rt6_lock); - for (rt1 = ip6_routing_table.leaf; rt1; rt1 = rt1->u.next) { - if (ipv6_addr_equal(saddr, &rt1->rt6i_gateway)) { - dst_hold(&rt1->u.dst); - dst_release(&rt->u.dst); - read_unlock(&rt6_lock); - rt = rt1; - goto source_ok; - } - } - read_unlock(&rt6_lock); + read_lock_bh(&rt6_lock); + fn = fib6_lookup(&ip6_routing_table, dest, NULL); +restart: + for (rt = fn->leaf; rt; rt = rt->u.next) { + /* + * Current route is on-link; redirect is always invalid. + * + * Seems, previous statement is not true. It could + * be node, which looks for us as on-link (f.e. proxy ndisc) + * But then router serving it might decide, that we should + * know truth 8)8) --ANK (980726). + */ + if (rt6_check_expired(rt)) + continue; + if (!(rt->rt6i_flags & RTF_GATEWAY)) + continue; + if (neigh->dev != rt->rt6i_dev) + continue; + if (!ipv6_addr_equal(saddr, &rt->rt6i_gateway)) + continue; + break; + } + if (rt) + dst_hold(&rt->u.dst); + else if (strict) { + while ((fn = fn->parent) != NULL) { + if (fn->fn_flags & RTN_ROOT) + break; + if (fn->fn_flags & RTN_RTINFO) + goto restart; } + } + read_unlock_bh(&rt6_lock); + + if (!rt) { if (net_ratelimit()) printk(KERN_DEBUG "rt6_redirect: source isn't a valid nexthop " "for redirect target\n"); - goto out; + return; } -source_ok: - /* * We have finally decided to accept it. */ |
