VPP-1305: Add support for tags

Change-Id: I9e759037295fe675abe426e565a562b1ec1e7d33
Signed-off-by: Jerome Tollet <jtollet@cisco.com>
diff --git a/src/vnet/devices/tap/tapv2.api b/src/vnet/devices/tap/tapv2.api
index 21c3ffb..167b7a6 100644
--- a/src/vnet/devices/tap/tapv2.api
+++ b/src/vnet/devices/tap/tapv2.api
@@ -19,7 +19,7 @@
     the Linux kernel TAP device driver
 */
 
-option version = "1.1.0";
+option version = "2.0.0";
 
 /** \brief Initialize a new tap interface with the given paramters
     @param client_index - opaque cookie to identify the sender
@@ -75,6 +75,7 @@
   u8 host_ip4_gw[4];
   u8 host_ip6_gw_set;
   u8 host_ip6_gw[16];
+  u8 tag[64];
 };
 
 /** \brief Reply for tap create reply
diff --git a/src/vnet/devices/tap/tapv2_api.c b/src/vnet/devices/tap/tapv2_api.c
index c6da0c9..f0c980a 100644
--- a/src/vnet/devices/tap/tapv2_api.c
+++ b/src/vnet/devices/tap/tapv2_api.c
@@ -52,6 +52,7 @@
 static void
 vl_api_tap_create_v2_t_handler (vl_api_tap_create_v2_t * mp)
 {
+  vnet_main_t *vnm = vnet_get_main ();
   vlib_main_t *vm = vlib_get_main ();
   vl_api_tap_create_v2_reply_t *rmp;
   vl_api_registration_t *reg;
@@ -114,6 +115,16 @@
   if (!reg)
     return;;
 
+  /* If a tag was supplied... */
+  if (mp->tag[0])
+    {
+      /* Make sure it's a proper C-string */
+      mp->tag[ARRAY_LEN (mp->tag) - 1] = 0;
+      u8 *tag = format (0, "%s%c", mp->tag, 0);
+      vnet_set_sw_interface_tag (vnm, tag, ap->sw_if_index);
+    }
+
+
   rmp = vl_msg_api_alloc (sizeof (*rmp));
   rmp->_vl_msg_id = ntohs (VL_API_TAP_CREATE_V2_REPLY);
   rmp->context = mp->context;
@@ -144,6 +155,7 @@
 static void
 vl_api_tap_delete_v2_t_handler (vl_api_tap_delete_v2_t * mp)
 {
+  vnet_main_t *vnm = vnet_get_main ();
   vlib_main_t *vm = vlib_get_main ();
   int rv;
   vpe_api_main_t *vam = &vpe_api_main;
@@ -165,7 +177,10 @@
   vl_api_send_msg (reg, (u8 *) rmp);
 
   if (!rv)
-    tap_send_sw_interface_event_deleted (vam, reg, sw_if_index);
+    {
+      vnet_clear_sw_interface_tag (vnm, sw_if_index);
+      tap_send_sw_interface_event_deleted (vam, reg, sw_if_index);
+    }
 }
 
 static void