ipvlan: implement VEPA mode

This is very similar to the Macvlan VEPA mode, however, there is some
difference. IPvlan uses the mac-address of the lower device, so the VEPA
mode has implications of ICMP-redirects for packets destined for its
immediate neighbors sharing same master since the packets will have same
source and dest mac. The external switch/router will send redirect msg.

Having said that, this will be useful tool in terms of debugging
since IPvlan will not switch packets within its slaves and rely completely
on the external entity as intended in 802.1Qbg.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 7 deletions

diff --git a/drivers/net/ipvlan/ipvlan_core.c b/drivers/net/ipvlan/ipvlan_core.c
index 72fd56de9c00..034ae4c57196 100644
--- a/drivers/net/ipvlan/ipvlan_core.c
+++ b/drivers/net/ipvlan/ipvlan_core.c
@@ -514,13 +514,15 @@ static int ipvlan_xmit_mode_l3(struct sk_buff *skb, struct net_device *dev)
         if (!lyr3h)
                 goto out;
 
-        addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
-        if (addr) {
-                if (ipvlan_is_private(ipvlan->port)) {
-                        consume_skb(skb);
-                        return NET_XMIT_DROP;
+        if (!ipvlan_is_vepa(ipvlan->port)) {
+                addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
+                if (addr) {
+                        if (ipvlan_is_private(ipvlan->port)) {
+                                consume_skb(skb);
+                                return NET_XMIT_DROP;
+                        }
+                        return ipvlan_rcv_frame(addr, &skb, true);
                 }
-                return ipvlan_rcv_frame(addr, &skb, true);
         }
 out:
         ipvlan_skb_crossing_ns(skb, ipvlan->phy_dev);
@@ -535,7 +537,8 @@ static int ipvlan_xmit_mode_l2(struct sk_buff *skb, struct net_device *dev)
         void *lyr3h;
         int addr_type;
 
-        if (ether_addr_equal(eth->h_dest, eth->h_source)) {
+        if (!ipvlan_is_vepa(ipvlan->port) &&
+            ether_addr_equal(eth->h_dest, eth->h_source)) {
                 lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
                 if (lyr3h) {
                         addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);