Further fix to SHG handling for ARP/ICMPv6 from BVI in a BD

For ARP/ICMPv6 packets received from a BVI in a BD, allow flood
to all remote VTEPs via VXLAN tunnels irrespective of SHG check
for ARP request or ICMPv6 neighbor solicitation packets only.
All other packets types will flood normally as per SHG check.

Change-Id: I17b1cef9015e363fb684c2b6506ed6c4efe70bba
Signed-off-by: John Lo <loj@cisco.com>
(cherry picked from commit 5b99133cff1ff0eb9043dd8bd3648b0b3aafa47e)

diff --git a/src/vnet/l2/l2_input.c b/src/vnet/l2/l2_input.c
index 041684f..591211e 100644 (file)
--- a/src/vnet/l2/l2_input.c
+++ b/src/vnet/l2/l2_input.c
@@ -23,6 +23,8 @@
 #include <vnet/ip/ip_packet.h>
 #include <vnet/ip/ip4_packet.h>
 #include <vnet/ip/ip6_packet.h>
+#include <vnet/fib/fib_node.h>
+#include <vnet/ethernet/arp_packet.h>
 #include <vlib/cli.h>
 #include <vnet/l2/l2_input.h>
 #include <vnet/l2/l2_output.h>
@@ -193,20 +195,37 @@ classify_and_dispatch (l2input_main_t * msm, vlib_buffer_t * b0, u32 * next0)
       if (ethertype != ETHERNET_TYPE_ARP &&
          (ethertype != ETHERNET_TYPE_IP6 || protocol != IP_PROTOCOL_ICMP6))
        feat_mask &= ~(L2INPUT_FEAT_ARP_TERM);
+
       /*
-       * Check for from-BVI processing - set SHG of ARP/ICMP6 packets from BVI
-       * to 0 so it can also flood to VXLAN tunnels or other ports with the
-       * same SHG as that of the BVI.
+       * For packet from BVI - set SHG of ARP request or ICMPv6 neighbor
+       * solicitation packet from BVI to 0 so it can also flood to VXLAN
+       * tunnels or other ports with the same SHG as that of the BVI.
        */
       else if (PREDICT_FALSE (vnet_buffer (b0)->sw_if_index[VLIB_TX] ==
                              L2INPUT_BVI))
-       vnet_buffer (b0)->l2.shg = 0;
+       {
+         if (ethertype == ETHERNET_TYPE_ARP)
+           {
+             ethernet_arp_header_t *arp0 = (ethernet_arp_header_t *) l3h0;
+             if (arp0->opcode ==
+                 clib_host_to_net_u16 (ETHERNET_ARP_OPCODE_request))
+               vnet_buffer (b0)->l2.shg = 0;
+           }
+         else                  /* must be ICMPv6 */
+           {
+             ip6_header_t *iph0 = (ip6_header_t *) l3h0;
+             icmp6_neighbor_solicitation_or_advertisement_header_t *ndh0;
+             ndh0 = ip6_next_header (iph0);
+             if (ndh0->icmp.type == ICMP6_neighbor_solicitation)
+               vnet_buffer (b0)->l2.shg = 0;
+           }
+       }
     }
   else
     {
       /*
-       * Check for from-BVI processing - set SHG of unicast packets from BVI
-       * to 0 so it is not dropped for VXLAN tunnels or other ports with the
+       * For packet from BVI - set SHG of unicast packet from BVI to 0 so it
+       * is not dropped on output to VXLAN tunnels or other ports with the
        * same SHG as that of the BVI.
        */
       if (PREDICT_FALSE (vnet_buffer (b0)->sw_if_index[VLIB_TX] ==