ipv6: Refactor __ip6_route_redirect

Move the nexthop evaluation of a fib entry to a helper that can be
leveraged for each fib6_nh in a multipath nexthop object.

In the move, 'continue' statements means the helper returns false
(loop should continue) and 'break' means return true (found the entry
of interest).

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 23 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 0e8becb1e455..d555edaaff13 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2407,6 +2407,35 @@ void ip6_sk_dst_store_flow(struct sock *sk, struct dst_entry *dst,
                       NULL);
 }
 
+static bool ip6_redirect_nh_match(struct fib6_info *f6i,
+                                  struct fib6_nh *nh,
+                                  struct flowi6 *fl6,
+                                  const struct in6_addr *gw,
+                                  struct rt6_info **ret)
+{
+        if (nh->fib_nh_flags & RTNH_F_DEAD || !nh->fib_nh_gw_family ||
+            fl6->flowi6_oif != nh->fib_nh_dev->ifindex)
+                return false;
+
+        /* rt_cache's gateway might be different from its 'parent'
+         * in the case of an ip redirect.
+         * So we keep searching in the exception table if the gateway
+         * is different.
+         */
+        if (!ipv6_addr_equal(gw, &nh->fib_nh_gw6)) {
+                struct rt6_info *rt_cache;
+
+                rt_cache = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
+                if (rt_cache &&
+                    ipv6_addr_equal(gw, &rt_cache->rt6i_gateway)) {
+                        *ret = rt_cache;
+                        return true;
+                }
+                return false;
+        }
+        return true;
+}
+
 /* Handle redirects */
 struct ip6rd_flowi {
         struct flowi6 fl6;
@@ -2420,7 +2449,7 @@ static struct rt6_info *__ip6_route_redirect(struct net *net,
                                              int flags)
 {
         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
-        struct rt6_info *ret = NULL, *rt_cache;
+        struct rt6_info *ret = NULL;
         struct fib6_info *rt;
         struct fib6_node *fn;
 
@@ -2438,34 +2467,15 @@ static struct rt6_info *__ip6_route_redirect(struct net *net,
         fn = fib6_node_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 restart:
         for_each_fib6_node_rt_rcu(fn) {
-                if (rt->fib6_nh.fib_nh_flags & RTNH_F_DEAD)
-                        continue;
                 if (fib6_check_expired(rt))
                         continue;
                 if (rt->fib6_flags & RTF_REJECT)
                         break;
-                if (!rt->fib6_nh.fib_nh_gw_family)
-                        continue;
                 if (fl6->flowi6_oif != rt->fib6_nh.fib_nh_dev->ifindex)
                         continue;
-                /* rt_cache's gateway might be different from its 'parent'
-                 * in the case of an ip redirect.
-                 * So we keep searching in the exception table if the gateway
-                 * is different.
-                 */
-                if (!ipv6_addr_equal(&rdfl->gateway, &rt->fib6_nh.fib_nh_gw6)) {
-                        rt_cache = rt6_find_cached_rt(rt,
-                                                      &fl6->daddr,
-                                                      &fl6->saddr);
-                        if (rt_cache &&
-                            ipv6_addr_equal(&rdfl->gateway,
-                                            &rt_cache->rt6i_gateway)) {
-                                ret = rt_cache;
-                                break;
-                        }
-                        continue;
-                }
-                break;
+                if (ip6_redirect_nh_match(rt, &rt->fib6_nh, fl6,
+                                          &rdfl->gateway, &ret))
+                        goto out;
         }
 
         if (!rt)