vxlan: add ipv6 proxy support

This patch adds the IPv6 version of "arp_reduce", ndisc_send_na()
will be needed.

Cc: David S. Miller <davem@davemloft.net>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 80 insertions, 2 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index c833763fe5c4..3ffb22d684a9 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1196,6 +1196,70 @@ out:
         return NETDEV_TX_OK;
 }
 
+#if IS_ENABLED(CONFIG_IPV6)
+static int neigh_reduce(struct net_device *dev, struct sk_buff *skb)
+{
+        struct vxlan_dev *vxlan = netdev_priv(dev);
+        struct neighbour *n;
+        union vxlan_addr ipa;
+        const struct ipv6hdr *iphdr;
+        const struct in6_addr *saddr, *daddr;
+        struct nd_msg *msg;
+        struct inet6_dev *in6_dev = NULL;
+
+        in6_dev = __in6_dev_get(dev);
+        if (!in6_dev)
+                goto out;
+
+        if (!pskb_may_pull(skb, skb->len))
+                goto out;
+
+        iphdr = ipv6_hdr(skb);
+        saddr = &iphdr->saddr;
+        daddr = &iphdr->daddr;
+
+        if (ipv6_addr_loopback(daddr) ||
+            ipv6_addr_is_multicast(daddr))
+                goto out;
+
+        msg = (struct nd_msg *)skb_transport_header(skb);
+        if (msg->icmph.icmp6_code != 0 ||
+            msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION)
+                goto out;
+
+        n = neigh_lookup(ipv6_stub->nd_tbl, daddr, dev);
+
+        if (n) {
+                struct vxlan_fdb *f;
+
+                if (!(n->nud_state & NUD_CONNECTED)) {
+                        neigh_release(n);
+                        goto out;
+                }
+
+                f = vxlan_find_mac(vxlan, n->ha);
+                if (f && vxlan_addr_any(&(first_remote_rcu(f)->remote_ip))) {
+                        /* bridge-local neighbor */
+                        neigh_release(n);
+                        goto out;
+                }
+
+                ipv6_stub->ndisc_send_na(dev, n, saddr, &msg->target,
+                                         !!in6_dev->cnf.forwarding,
+                                         true, false, false);
+                neigh_release(n);
+        } else if (vxlan->flags & VXLAN_F_L3MISS) {
+                ipa.sin6.sin6_addr = *daddr;
+                ipa.sa.sa_family = AF_INET6;
+                vxlan_ip_miss(dev, &ipa);
+        }
+
+out:
+        consume_skb(skb);
+        return NETDEV_TX_OK;
+}
+#endif
+
 static bool route_shortcircuit(struct net_device *dev, struct sk_buff *skb)
 {
         struct vxlan_dev *vxlan = netdev_priv(dev);
@@ -1677,8 +1741,22 @@ static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev)
         skb_reset_mac_header(skb);
         eth = eth_hdr(skb);
 
-        if ((vxlan->flags & VXLAN_F_PROXY) && ntohs(eth->h_proto) == ETH_P_ARP)
-                return arp_reduce(dev, skb);
+        if ((vxlan->flags & VXLAN_F_PROXY)) {
+                if (ntohs(eth->h_proto) == ETH_P_ARP)
+                        return arp_reduce(dev, skb);
+#if IS_ENABLED(CONFIG_IPV6)
+                else if (ntohs(eth->h_proto) == ETH_P_IPV6 &&
+                         skb->len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
+                         ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) {
+                                struct nd_msg *msg;
+
+                                msg = (struct nd_msg *)skb_transport_header(skb);
+                                if (msg->icmph.icmp6_code == 0 &&
+                                    msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION)
+                                        return neigh_reduce(dev, skb);
+                }
+#endif
+        }
 
         f = vxlan_find_mac(vxlan, eth->h_dest);
         did_rsc = false;