ipv4: Generalize ip_do_redirect() and hook into new dst_ops->redirect.
All of the redirect acceptance policy is now contained within.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index f8921b4..f3d2565 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -149,6 +149,7 @@
static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
static void ipv4_link_failure(struct sk_buff *skb);
static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
+static void ip_do_redirect(struct dst_entry *dst, struct sk_buff *skb);
static int rt_garbage_collect(struct dst_ops *ops);
static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
@@ -179,6 +180,7 @@
.negative_advice = ipv4_negative_advice,
.link_failure = ipv4_link_failure,
.update_pmtu = ip_rt_update_pmtu,
+ .redirect = ip_do_redirect,
.local_out = __ip_local_out,
.neigh_lookup = ipv4_neigh_lookup,
};
@@ -1271,42 +1273,18 @@
spin_unlock_bh(rt_hash_lock_addr(hash));
}
-static void ip_do_redirect(struct rtable *rt, __be32 old_gw, __be32 new_gw)
-{
- struct neighbour *n;
-
- if (rt->rt_gateway != old_gw)
- return;
-
- n = ipv4_neigh_lookup(&rt->dst, NULL, &new_gw);
- if (n) {
- if (!(n->nud_state & NUD_VALID)) {
- neigh_event_send(n, NULL);
- } else {
- rt->rt_gateway = new_gw;
- rt->rt_flags |= RTCF_REDIRECTED;
- call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
- }
- neigh_release(n);
- }
-}
-
-/* called in rcu_read_lock() section */
-void ip_rt_redirect(struct sk_buff *skb, __be32 new_gw)
+static void ip_do_redirect(struct dst_entry *dst, struct sk_buff *skb)
{
const struct iphdr *iph = (const struct iphdr *) skb->data;
+ __be32 new_gw = icmp_hdr(skb)->un.gateway;
__be32 old_gw = ip_hdr(skb)->saddr;
+ struct net_device *dev = skb->dev;
__be32 daddr = iph->daddr;
__be32 saddr = iph->saddr;
- struct net_device *dev = skb->dev;
- struct in_device *in_dev = __in_dev_get_rcu(dev);
- int ikeys[2] = { dev->ifindex, 0 };
- __be32 skeys[2] = { saddr, 0 };
+ struct in_device *in_dev;
+ struct neighbour *n;
+ struct rtable *rt;
struct net *net;
- int s, i;
-
- if (!in_dev)
- return;
switch (icmp_hdr(skb)->code & 7) {
case ICMP_REDIR_NET:
@@ -1319,6 +1297,14 @@
return;
}
+ rt = (struct rtable *) dst;
+ if (rt->rt_gateway != old_gw)
+ return;
+
+ in_dev = __in_dev_get_rcu(dev);
+ if (!in_dev)
+ return;
+
net = dev_net(dev);
if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
@@ -1335,6 +1321,43 @@
goto reject_redirect;
}
+ n = ipv4_neigh_lookup(dst, NULL, &new_gw);
+ if (n) {
+ if (!(n->nud_state & NUD_VALID)) {
+ neigh_event_send(n, NULL);
+ } else {
+ rt->rt_gateway = new_gw;
+ rt->rt_flags |= RTCF_REDIRECTED;
+ call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
+ }
+ neigh_release(n);
+ }
+ return;
+
+reject_redirect:
+#ifdef CONFIG_IP_ROUTE_VERBOSE
+ if (IN_DEV_LOG_MARTIANS(in_dev))
+ net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
+ " Advised path = %pI4 -> %pI4\n",
+ &old_gw, dev->name, &new_gw,
+ &saddr, &daddr);
+#endif
+ ;
+}
+
+/* called in rcu_read_lock() section */
+void ip_rt_redirect(struct sk_buff *skb, __be32 new_gw)
+{
+ const struct iphdr *iph = (const struct iphdr *) skb->data;
+ __be32 daddr = iph->daddr;
+ __be32 saddr = iph->saddr;
+ struct net_device *dev = skb->dev;
+ int ikeys[2] = { dev->ifindex, 0 };
+ __be32 skeys[2] = { saddr, 0 };
+ struct net *net;
+ int s, i;
+
+ net = dev_net(dev);
for (s = 0; s < 2; s++) {
for (i = 0; i < 2; i++) {
unsigned int hash;
@@ -1358,21 +1381,12 @@
rt->dst.dev != dev)
continue;
- ip_do_redirect(rt, old_gw, new_gw);
+ ip_do_redirect(&rt->dst, skb);
}
}
}
return;
-reject_redirect:
-#ifdef CONFIG_IP_ROUTE_VERBOSE
- if (IN_DEV_LOG_MARTIANS(in_dev))
- net_info_ratelimited("Redirect from %pI4 on %s about %pI4 ignored\n"
- " Advised path = %pI4 -> %pI4\n",
- &old_gw, dev->name, &new_gw,
- &saddr, &daddr);
-#endif
- ;
}
static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)