Add vxlan-bypass feature to IP6 forwarding path

Add vxlan-bypass feature which can be enabled on the IP6 underlay
interface which receive VXLAN packets to accelerate VXLAN decap
processing. The CLI to enable/disable it is:
    set interface ip6 vxlan-bypass <interface> [del]
The vxlan-bypass feature is already supported on the IP4 underlay
interface. The CLI to enable/disable it is:
    set interface ip vxlan-bypass <interface> [del]

Move vxlan-bypass API/CLI support code from decap.c to vxlan.c.
Also fixed two issues in the VXLAN decap path in the vxlan-input node:
1. Add verification of VXLAN packet FIB index with the encap-vrf-id
   of the VXLAN tunnel.
2. Fix checking of VXLANoIPv6 packet mcast DIP against that of the
   IP6 mcast VXLAN tunnel.

Change-Id: I2bad4074a468c48fbb8bb5ac64f6437190756ed2
Signed-off-by: John Lo <loj@cisco.com>

1 files changed, 171 insertions, 0 deletions

diff --git a/src/vnet/vxlan/vxlan.c b/src/vnet/vxlan/vxlan.c
index 9ed42875..02465eb4 100644
--- a/src/vnet/vxlan/vxlan.c
+++ b/src/vnet/vxlan/vxlan.c
@@ -921,6 +921,177 @@ VLIB_CLI_COMMAND (show_vxlan_tunnel_command, static) = {
 /* *INDENT-ON* */
 
 
+void vnet_int_vxlan_bypass_mode (u32 sw_if_index,
+				 u8 is_ip6,
+				 u8 is_enable)
+{
+  if (is_ip6)
+    vnet_feature_enable_disable ("ip6-unicast", "ip6-vxlan-bypass",
+				 sw_if_index, is_enable, 0, 0);
+  else
+    vnet_feature_enable_disable ("ip4-unicast", "ip4-vxlan-bypass",
+				 sw_if_index, is_enable, 0, 0);
+}
+
+
+static clib_error_t *
+set_ip_vxlan_bypass (u32 is_ip6,
+		     unformat_input_t * input,
+		     vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, * line_input = &_line_input;
+  vnet_main_t * vnm = vnet_get_main();
+  clib_error_t * error = 0;
+  u32 sw_if_index, is_enable;
+
+  sw_if_index = ~0;
+  is_enable = 1;
+
+  if (! unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat_user (line_input, unformat_vnet_sw_interface, vnm, &sw_if_index))
+	  ;
+      else if (unformat (line_input, "del"))
+        is_enable = 0;
+      else
+        {
+	  error = unformat_parse_error (line_input);
+	  goto done;
+	}
+    }
+
+  if (~0 == sw_if_index)
+    {
+      error = clib_error_return (0, "unknown interface `%U'",
+				 format_unformat_error, line_input);
+      goto done;
+    }
+
+  vnet_int_vxlan_bypass_mode (sw_if_index, is_ip6, is_enable);
+
+ done:
+  return error;
+}
+
+static clib_error_t *
+set_ip4_vxlan_bypass (vlib_main_t * vm,
+		      unformat_input_t * input,
+		      vlib_cli_command_t * cmd)
+{
+  return set_ip_vxlan_bypass (0, input, cmd);
+}
+
+/*?
+ * This command adds the 'ip4-vxlan-bypass' graph node for a given interface. 
+ * By adding the IPv4 vxlan-bypass graph node to an interface, the node checks
+ *  for and validate input vxlan packet and bypass ip4-lookup, ip4-local, 
+ * ip4-udp-lookup nodes to speedup vxlan packet forwarding. This node will 
+ * cause extra overhead to for non-vxlan packets which is kept at a minimum.
+ *
+ * @cliexpar
+ * @parblock
+ * Example of graph node before ip4-vxlan-bypass is enabled:
+ * @cliexstart{show vlib graph ip4-vxlan-bypass}
+ *            Name                      Next                    Previous
+ * ip4-vxlan-bypass                error-drop [0]
+ *                                vxlan4-input [1]
+ *                                 ip4-lookup [2]      
+ * @cliexend
+ *
+ * Example of how to enable ip4-vxlan-bypass on an interface:
+ * @cliexcmd{set interface ip vxlan-bypass GigabitEthernet2/0/0}
+ *
+ * Example of graph node after ip4-vxlan-bypass is enabled:
+ * @cliexstart{show vlib graph ip4-vxlan-bypass}
+ *            Name                      Next                    Previous         
+ * ip4-vxlan-bypass                error-drop [0]               ip4-input        
+ *                                vxlan4-input [1]        ip4-input-no-checksum  
+ *                                 ip4-lookup [2]      
+ * @cliexend
+ *
+ * Example of how to display the feature enabed on an interface:
+ * @cliexstart{show ip interface features GigabitEthernet2/0/0}
+ * IP feature paths configured on GigabitEthernet2/0/0...
+ * ...
+ * ipv4 unicast:
+ *   ip4-vxlan-bypass
+ *   ip4-lookup
+ * ...
+ * @cliexend
+ *
+ * Example of how to disable ip4-vxlan-bypass on an interface:
+ * @cliexcmd{set interface ip vxlan-bypass GigabitEthernet2/0/0 del}
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (set_interface_ip_vxlan_bypass_command, static) = {
+  .path = "set interface ip vxlan-bypass",
+  .function = set_ip4_vxlan_bypass,
+  .short_help = "set interface ip vxlan-bypass <interface> [del]",
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+set_ip6_vxlan_bypass (vlib_main_t * vm,
+		      unformat_input_t * input,
+		      vlib_cli_command_t * cmd)
+{
+  return set_ip_vxlan_bypass (1, input, cmd);
+}
+
+/*?
+ * This command adds the 'ip6-vxlan-bypass' graph node for a given interface. 
+ * By adding the IPv6 vxlan-bypass graph node to an interface, the node checks
+ *  for and validate input vxlan packet and bypass ip6-lookup, ip6-local, 
+ * ip6-udp-lookup nodes to speedup vxlan packet forwarding. This node will 
+ * cause extra overhead to for non-vxlan packets which is kept at a minimum.
+ *
+ * @cliexpar
+ * @parblock
+ * Example of graph node before ip6-vxlan-bypass is enabled:
+ * @cliexstart{show vlib graph ip6-vxlan-bypass}
+ *            Name                      Next                    Previous
+ * ip6-vxlan-bypass                error-drop [0]
+ *                                vxlan6-input [1]
+ *                                 ip6-lookup [2]      
+ * @cliexend
+ *
+ * Example of how to enable ip6-vxlan-bypass on an interface:
+ * @cliexcmd{set interface ip6 vxlan-bypass GigabitEthernet2/0/0}
+ *
+ * Example of graph node after ip6-vxlan-bypass is enabled:
+ * @cliexstart{show vlib graph ip6-vxlan-bypass}
+ *            Name                      Next                    Previous         
+ * ip6-vxlan-bypass                error-drop [0]               ip6-input        
+ *                                vxlan6-input [1]        ip4-input-no-checksum  
+ *                                 ip6-lookup [2]      
+ * @cliexend
+ *
+ * Example of how to display the feature enabed on an interface:
+ * @cliexstart{show ip interface features GigabitEthernet2/0/0}
+ * IP feature paths configured on GigabitEthernet2/0/0...
+ * ...
+ * ipv6 unicast:
+ *   ip6-vxlan-bypass
+ *   ip6-lookup
+ * ...
+ * @cliexend
+ *
+ * Example of how to disable ip6-vxlan-bypass on an interface:
+ * @cliexcmd{set interface ip6 vxlan-bypass GigabitEthernet2/0/0 del}
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (set_interface_ip6_vxlan_bypass_command, static) = {
+  .path = "set interface ip6 vxlan-bypass",
+  .function = set_ip6_vxlan_bypass,
+  .short_help = "set interface ip vxlan-bypass <interface> [del]",
+};
+/* *INDENT-ON* */
+
 clib_error_t *vxlan_init (vlib_main_t *vm)
 {
   vxlan_main_t * vxm = &vxlan_main;