ipv6: Pull main logic of rt6_redirect() into rt6_do_redirect().

Hook it into dst_ops->redirect as well.

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

1 files changed, 49 insertions, 31 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 73cf3f78aaa8..545b1526c143 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -79,6 +79,7 @@ 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);
 
 #ifdef CONFIG_IPV6_ROUTE_INFO
 static struct rt6_info *rt6_add_route_info(struct net *net,
@@ -174,6 +175,7 @@ static struct dst_ops ip6_dst_ops_template = {
         .negative_advice        =       ip6_negative_advice,
         .link_failure           =       ip6_link_failure,
         .update_pmtu            =       ip6_rt_update_pmtu,
+        .redirect               =       rt6_do_redirect,
         .local_out              =       __ip6_local_out,
         .neigh_lookup           =       ip6_neigh_lookup,
 };
@@ -1690,28 +1692,26 @@ static struct rt6_info *ip6_route_redirect(const struct in6_addr *dest,
                                                    flags, __ip6_route_redirect);
 }
 
-void rt6_redirect(struct sk_buff *skb)
+static void rt6_do_redirect(struct dst_entry *dst, struct sk_buff *skb)
 {
         struct net *net = dev_net(skb->dev);
         struct netevent_redirect netevent;
         struct rt6_info *rt, *nrt = NULL;
         const struct in6_addr *target;
-        struct neighbour *old_neigh;
-        const struct in6_addr *dest;
-        const struct in6_addr *src;
-        const struct in6_addr *saddr;
         struct ndisc_options ndopts;
+        const struct in6_addr *dest;
+        struct neighbour *old_neigh;
         struct inet6_dev *in6_dev;
         struct neighbour *neigh;
         struct icmp6hdr *icmph;
-        int on_link, optlen;
-        u8 *lladdr = NULL;
+        int optlen, on_link;
+        u8 *lladdr;
 
         optlen = skb->tail - skb->transport_header;
         optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
 
         if (optlen < 0) {
-                net_dbg_ratelimited("rt6_redirect: packet too short\n");
+                net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
                 return;
         }
 
@@ -1720,15 +1720,16 @@ void rt6_redirect(struct sk_buff *skb)
         dest = target + 1;
 
         if (ipv6_addr_is_multicast(dest)) {
-                net_dbg_ratelimited("rt6_redirect: destination address is multicast\n");
+                net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
                 return;
         }
 
+        on_link = 0;
         if (ipv6_addr_equal(dest, target)) {
                 on_link = 1;
         } else if (ipv6_addr_type(target) !=
                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
-                net_dbg_ratelimited("rt6_redirect: target address is not link-local unicast\n");
+                net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
                 return;
         }
 
@@ -1747,6 +1748,8 @@ void rt6_redirect(struct sk_buff *skb)
                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
                 return;
         }
+
+        lladdr = NULL;
         if (ndopts.nd_opts_tgt_lladdr) {
                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
                                              skb->dev);
@@ -1756,19 +1759,26 @@ void rt6_redirect(struct sk_buff *skb)
                 }
         }
 
-        neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
-        if (!neigh)
+        rt = (struct rt6_info *) dst;
+        if (rt == net->ipv6.ip6_null_entry) {
+                net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
                 return;
+        }
 
-        src = &ipv6_hdr(skb)->daddr;
-        saddr = &ipv6_hdr(skb)->saddr;
+        /* Redirect received -> path was valid.
+         * Look, redirects are sent only in response to data packets,
+         * so that this nexthop apparently is reachable. --ANK
+         */
+        dst_confirm(&rt->dst);
 
-        rt = ip6_route_redirect(dest, src, saddr, neigh->dev);
+        neigh = __neigh_lookup(&nd_tbl, target, skb->dev, 1);
+        if (!neigh)
+                return;
 
-        if (rt == net->ipv6.ip6_null_entry) {
-                net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
+        /* Duplicate redirect: silently ignore. */
+        old_neigh = rt->n;
+        if (neigh == old_neigh)
                 goto out;
-        }
 
         /*
          *      We have finally decided to accept it.
@@ -1781,18 +1791,6 @@ void rt6_redirect(struct sk_buff *skb)
                                      NEIGH_UPDATE_F_ISROUTER))
                      );
 
-        /*
-         * Redirect received -> path was valid.
-         * Look, redirects are sent only in response to data packets,
-         * so that this nexthop apparently is reachable. --ANK
-         */
-        dst_confirm(&rt->dst);
-
-        /* Duplicate redirect: silently ignore. */
-        old_neigh = rt->n;
-        if (neigh == old_neigh)
-                goto out;
-
         nrt = ip6_rt_copy(rt, dest);
         if (!nrt)
                 goto out;
@@ -1815,12 +1813,32 @@ void rt6_redirect(struct sk_buff *skb)
         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
 
         if (rt->rt6i_flags & RTF_CACHE) {
+                rt = (struct rt6_info *) dst_clone(&rt->dst);
                 ip6_del_rt(rt);
-                return;
         }
 
 out:
         neigh_release(neigh);
+}
+
+void rt6_redirect(struct sk_buff *skb)
+{
+        const struct in6_addr *target;
+        const struct in6_addr *dest;
+        const struct in6_addr *src;
+        const struct in6_addr *saddr;
+        struct icmp6hdr *icmph;
+        struct rt6_info *rt;
+
+        icmph = icmp6_hdr(skb);
+        target = (const struct in6_addr *) (icmph + 1);
+        dest = target + 1;
+
+        src = &ipv6_hdr(skb)->daddr;
+        saddr = &ipv6_hdr(skb)->saddr;
+
+        rt = ip6_route_redirect(dest, src, saddr, skb->dev);
+        rt6_do_redirect(&rt->dst, skb);
         dst_release(&rt->dst);
 }