net: vrf: Handle ipv6 multicast and link-local addresses

[cascardo/linux.git] / drivers / net / vrf.c

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index d2ce76c..0b5b3c2 100644 (file)
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -785,9 +785,63 @@ out:
        return rc;
 }
 
+static struct rt6_info *vrf_ip6_route_lookup(struct net *net,
+                                            const struct net_device *dev,
+                                            struct flowi6 *fl6,
+                                            int ifindex,
+                                            int flags)
+{
+       struct net_vrf *vrf = netdev_priv(dev);
+       struct fib6_table *table = NULL;
+       struct rt6_info *rt6;
+
+       rcu_read_lock();
+
+       /* fib6_table does not have a refcnt and can not be freed */
+       rt6 = rcu_dereference(vrf->rt6);
+       if (likely(rt6))
+               table = rt6->rt6i_table;
+
+       rcu_read_unlock();
+
+       if (!table)
+               return NULL;
+
+       return ip6_pol_route(net, table, ifindex, fl6, flags);
+}
+
+static void vrf_ip6_input_dst(struct sk_buff *skb, struct net_device *vrf_dev,
+                             int ifindex)
+{
+       const struct ipv6hdr *iph = ipv6_hdr(skb);
+       struct flowi6 fl6 = {
+               .daddr          = iph->daddr,
+               .saddr          = iph->saddr,
+               .flowlabel      = ip6_flowinfo(iph),
+               .flowi6_mark    = skb->mark,
+               .flowi6_proto   = iph->nexthdr,
+               .flowi6_iif     = ifindex,
+       };
+       struct net *net = dev_net(vrf_dev);
+       struct rt6_info *rt6;
+
+       rt6 = vrf_ip6_route_lookup(net, vrf_dev, &fl6, ifindex,
+                                  RT6_LOOKUP_F_HAS_SADDR | RT6_LOOKUP_F_IFACE);
+       if (unlikely(!rt6))
+               return;
+
+       if (unlikely(&rt6->dst == &net->ipv6.ip6_null_entry->dst))
+               return;
+
+       skb_dst_set(skb, &rt6->dst);
+}
+
 static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
                                   struct sk_buff *skb)
 {
+       int orig_iif = skb->skb_iif;
+       bool need_strict;
+
        /* loopback traffic; do not push through packet taps again.
         * Reset pkt_type for upper layers to process skb
         */
@@ -798,8 +852,11 @@ static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
                goto out;
        }
 
-       /* if packet is NDISC keep the ingress interface */
-       if (!ipv6_ndisc_frame(skb)) {
+       /* if packet is NDISC or addressed to multicast or link-local
+        * then keep the ingress interface
+        */
+       need_strict = rt6_need_strict(&ipv6_hdr(skb)->daddr);
+       if (!ipv6_ndisc_frame(skb) && !need_strict) {
                skb->dev = vrf_dev;
                skb->skb_iif = vrf_dev->ifindex;
 
@@ -810,6 +867,9 @@ static struct sk_buff *vrf_ip6_rcv(struct net_device *vrf_dev,
                IP6CB(skb)->flags |= IP6SKB_L3SLAVE;
        }
 
+       if (need_strict)
+               vrf_ip6_input_dst(skb, vrf_dev, orig_iif);
+
 out:
        return skb;
 }
@@ -863,11 +923,35 @@ static struct sk_buff *vrf_l3_rcv(struct net_device *vrf_dev,
 static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
                                         struct flowi6 *fl6)
 {
+       bool need_strict = rt6_need_strict(&fl6->daddr);
+       struct net_vrf *vrf = netdev_priv(dev);
+       struct net *net = dev_net(dev);
        struct dst_entry *dst = NULL;
+       struct rt6_info *rt;
 
-       if (!(fl6->flowi6_flags & FLOWI_FLAG_L3MDEV_SRC)) {
-               struct net_vrf *vrf = netdev_priv(dev);
-               struct rt6_info *rt;
+       /* send to link-local or multicast address */
+       if (need_strict) {
+               int flags = RT6_LOOKUP_F_IFACE;
+
+               /* VRF device does not have a link-local address and
+                * sending packets to link-local or mcast addresses over
+                * a VRF device does not make sense
+                */
+               if (fl6->flowi6_oif == dev->ifindex) {
+                       struct dst_entry *dst = &net->ipv6.ip6_null_entry->dst;
+
+                       dst_hold(dst);
+                       return dst;
+               }
+
+               if (!ipv6_addr_any(&fl6->saddr))
+                       flags |= RT6_LOOKUP_F_HAS_SADDR;
+
+               rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif, flags);
+               if (rt)
+                       dst = &rt->dst;
+
+       } else if (!(fl6->flowi6_flags & FLOWI_FLAG_L3MDEV_SRC)) {
 
                rcu_read_lock();
 
@@ -880,6 +964,10 @@ static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
                rcu_read_unlock();
        }
 
+       /* make sure oif is set to VRF device for lookup */
+       if (!need_strict)
+               fl6->flowi6_oif = dev->ifindex;
+
        return dst;
 }
 #endif