net: Pass optional SKB and SK arguments to dst_ops->{update_pmtu,redirect}()

This will be used so that we can compose a full flow key.

Even though we have a route in this context, we need more.  In the
future the routes will be without destination address, source address,
etc. keying.  One ipv4 route will cover entire subnets, etc.

In this environment we have to have a way to possess persistent storage
for redirects and PMTU information.  This persistent storage will exist
in the FIB tables, and that's why we'll need to be able to rebuild a
full lookup flow key here.  Using that flow key will do a fib_lookup()
and create/update the persistent entry.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 8 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 2a4c8d48977f..31af1ed6c1dc 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -78,8 +78,10 @@ static int		 ip6_dst_gc(struct dst_ops *ops);
 static int              ip6_pkt_discard(struct sk_buff *skb);
 static int              ip6_pkt_discard_out(struct sk_buff *skb);
 static void             ip6_link_failure(struct sk_buff *skb);
-static void             ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
-static void             rt6_do_redirect(struct dst_entry *dst, struct sk_buff *skb);
+static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
+                                           struct sk_buff *skb, u32 mtu);
+static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
+                                        struct sk_buff *skb);
 
 #ifdef CONFIG_IPV6_ROUTE_INFO
 static struct rt6_info *rt6_add_route_info(struct net *net,
@@ -187,11 +189,13 @@ static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
         return mtu ? : dst->dev->mtu;
 }
 
-static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
+static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
+                                         struct sk_buff *skb, u32 mtu)
 {
 }
 
-static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sk_buff *skb)
+static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
+                                      struct sk_buff *skb)
 {
 }
 
@@ -1071,7 +1075,8 @@ static void ip6_link_failure(struct sk_buff *skb)
         }
 }
 
-static void ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
+static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
+                               struct sk_buff *skb, u32 mtu)
 {
         struct rt6_info *rt6 = (struct rt6_info*)dst;
 
@@ -1108,7 +1113,7 @@ void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
 
         dst = ip6_route_output(net, NULL, &fl6);
         if (!dst->error)
-                ip6_rt_update_pmtu(dst, ntohl(mtu));
+                ip6_rt_update_pmtu(dst, NULL, skb, ntohl(mtu));
         dst_release(dst);
 }
 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
@@ -1136,7 +1141,7 @@ void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
 
         dst = ip6_route_output(net, NULL, &fl6);
         if (!dst->error)
-                rt6_do_redirect(dst, skb);
+                rt6_do_redirect(dst, NULL, skb);
         dst_release(dst);
 }
 EXPORT_SYMBOL_GPL(ip6_redirect);
@@ -1639,7 +1644,7 @@ static int ip6_route_del(struct fib6_config *cfg)
         return err;
 }
 
-static void rt6_do_redirect(struct dst_entry *dst, struct sk_buff *skb)
+static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
 {
         struct net *net = dev_net(skb->dev);
         struct netevent_redirect netevent;