tap: add initial support for tun

Type: feature

Change-Id: I699a01ac925fe5c475a36032edb7018618bb4dd4
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

5 files changed, 72 insertions, 25 deletions

diff --git a/src/vnet/devices/virtio/device.c b/src/vnet/devices/virtio/device.c
index 1ee94806842..9d04474ada0 100644
--- a/src/vnet/devices/virtio/device.c
+++ b/src/vnet/devices/virtio/device.c
@@ -21,6 +21,7 @@
 
 #include <vlib/vlib.h>
 #include <vlib/unix/unix.h>
+#include <vnet/vnet.h>
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/gso/gso.h>
 #include <vnet/ip/ip4_packet.h>
@@ -343,7 +344,7 @@ add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif,
 	      id->len = b->current_length;
 	    }
 	}
-      else			/* VIRTIO_IF_TYPE_TAP */
+      else			/* VIRTIO_IF_TYPE_[TAP | TUN] */
 	{
 	  d->addr = pointer_to_uword (id);
 	  /* first buffer in chain */
@@ -612,6 +613,7 @@ VNET_DEVICE_CLASS (virtio_device_class) = {
   .subif_add_del_function = virtio_subif_add_del_function,
   .rx_mode_change_function = virtio_interface_rx_mode_change,
 };
+
 /* *INDENT-ON* */
 
 /*
diff --git a/src/vnet/devices/virtio/format.c b/src/vnet/devices/virtio/format.c
index 729635de35b..fe46d92cba9 100644
--- a/src/vnet/devices/virtio/format.c
+++ b/src/vnet/devices/virtio/format.c
@@ -36,6 +36,8 @@ format_virtio_device_name (u8 * s, va_list * args)
     s = format (s, "virtio-%x/%x/%x/%x", vif->pci_addr.domain,
 		vif->pci_addr.bus, vif->pci_addr.slot,
 		vif->pci_addr.function);
+  else if (vif->type == VIRTIO_IF_TYPE_TUN)
+    s = format (s, "tun%u", vif->id);
   else
     s = format (s, "virtio-%lu", vif->dev_instance);
 
@@ -49,6 +51,8 @@ format_virtio_log_name (u8 * s, va_list * args)
 
   if (vif->type == VIRTIO_IF_TYPE_TAP)
     s = format (s, "tap%u", vif->id);
+  else if (vif->type == VIRTIO_IF_TYPE_TUN)
+    s = format (s, "tun%u", vif->id);
   else if (vif->type == VIRTIO_IF_TYPE_PCI)
     s = format (s, "%U", format_vlib_pci_addr, &vif->pci_addr);
   else
diff --git a/src/vnet/devices/virtio/node.c b/src/vnet/devices/virtio/node.c
index 3bb23662c50..8d7c9360b00 100644
--- a/src/vnet/devices/virtio/node.c
+++ b/src/vnet/devices/virtio/node.c
@@ -143,27 +143,44 @@ more:
 
 static_always_inline void
 virtio_needs_csum (vlib_buffer_t * b0, struct virtio_net_hdr_v1 *hdr,
-		   u8 * l4_proto, u8 * l4_hdr_sz)
+		   u8 * l4_proto, u8 * l4_hdr_sz, virtio_if_type_t type)
 {
   if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
 
     {
-      ethernet_header_t *eh =
-	(ethernet_header_t *) vlib_buffer_get_current (b0);
-      u16 ethertype = clib_net_to_host_u16 (eh->type);
-      u16 l2hdr_sz = sizeof (ethernet_header_t);
-
-      if (ethernet_frame_is_tagged (ethertype))
+      u16 ethertype = 0, l2hdr_sz = 0;
+      if (type != VIRTIO_IF_TYPE_TUN)
 	{
-	  ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eh + 1);
+	  ethernet_header_t *eh =
+	    (ethernet_header_t *) vlib_buffer_get_current (b0);
+	  ethertype = clib_net_to_host_u16 (eh->type);
+	  l2hdr_sz = sizeof (ethernet_header_t);
 
-	  ethertype = clib_net_to_host_u16 (vlan->type);
-	  l2hdr_sz += sizeof (*vlan);
-	  if (ethertype == ETHERNET_TYPE_VLAN)
+	  if (ethernet_frame_is_tagged (ethertype))
 	    {
-	      vlan++;
+	      ethernet_vlan_header_t *vlan =
+		(ethernet_vlan_header_t *) (eh + 1);
+
 	      ethertype = clib_net_to_host_u16 (vlan->type);
 	      l2hdr_sz += sizeof (*vlan);
+	      if (ethertype == ETHERNET_TYPE_VLAN)
+		{
+		  vlan++;
+		  ethertype = clib_net_to_host_u16 (vlan->type);
+		  l2hdr_sz += sizeof (*vlan);
+		}
+	    }
+	}
+      else
+	{
+	  switch (b0->data[0] & 0xf0)
+	    {
+	    case 0x40:
+	      ethertype = ETHERNET_TYPE_IP4;
+	      break;
+	    case 0x60:
+	      ethertype = ETHERNET_TYPE_IP6;
+	      break;
 	    }
 	}
 
@@ -285,7 +302,7 @@ virtio_device_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 	  b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
 
 	  if (checksum_offload_enabled)
-	    virtio_needs_csum (b0, hdr, &l4_proto, &l4_hdr_sz);
+	    virtio_needs_csum (b0, hdr, &l4_proto, &l4_hdr_sz, vif->type);
 
 	  if (gso_enabled)
 	    fill_gso_buffer_flags (b0, hdr, l4_proto, l4_hdr_sz);
@@ -321,6 +338,22 @@ virtio_device_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 		  n_left--;
 		}
 	    }
+	  if (PREDICT_FALSE (vif->type == VIRTIO_IF_TYPE_TUN))
+	    {
+	      switch (b0->data[0] & 0xf0)
+		{
+		case 0x40:
+		  next0 = VNET_DEVICE_INPUT_NEXT_IP4_INPUT;
+		  break;
+		case 0x60:
+		  next0 = VNET_DEVICE_INPUT_NEXT_IP6_INPUT;
+		  break;
+		default:
+		  next0 = VNET_DEVICE_INPUT_NEXT_DROP;
+		  break;
+		}
+	    }
+
 
 	  if (PREDICT_FALSE (vif->per_interface_next_index != ~0))
 	    next0 = vif->per_interface_next_index;
diff --git a/src/vnet/devices/virtio/virtio.c b/src/vnet/devices/virtio/virtio.c
index d78c9114e5c..00a588af346 100644
--- a/src/vnet/devices/virtio/virtio.c
+++ b/src/vnet/devices/virtio/virtio.c
@@ -294,7 +294,7 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 	  vlib_cli_output (vm, "  PCI Address: %U", format_vlib_pci_addr,
 			   &vif->pci_addr);
 	}
-      if (type == VIRTIO_IF_TYPE_TAP)
+      if (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_TUN))
 	{
 	  u8 *str = 0;
 	  if (vif->host_if_name)
@@ -304,8 +304,9 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 	  if (vif->host_mtu_size)
 	    vlib_cli_output (vm, "  host-mtu-size \"%d\"",
 			     vif->host_mtu_size);
-	  vlib_cli_output (vm, "  host-mac-addr: %U",
-			   format_ethernet_address, vif->host_mac_addr);
+	  if (type == VIRTIO_IF_TYPE_TAP)
+	    vlib_cli_output (vm, "  host-mac-addr: %U",
+			     format_ethernet_address, vif->host_mac_addr);
 
 	  vec_foreach_index (i, vif->vhost_fds)
 	    str = format (str, " %d", vif->vhost_fds[i]);
@@ -315,8 +316,9 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 	}
       vlib_cli_output (vm, "  gso-enabled %d", vif->gso_enabled);
       vlib_cli_output (vm, "  csum-enabled %d", vif->csum_offload_enabled);
-      vlib_cli_output (vm, "  Mac Address: %U", format_ethernet_address,
-		       vif->mac_addr);
+      if (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_PCI))
+	vlib_cli_output (vm, "  Mac Address: %U", format_ethernet_address,
+			 vif->mac_addr);
       vlib_cli_output (vm, "  Device instance: %u", vif->dev_instance);
       vlib_cli_output (vm, "  flags 0x%x", vif->flags);
       flag_entry = (struct feat_struct *) &flags_array;
@@ -366,7 +368,7 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 			 "    avail.flags 0x%x avail.idx %d used.flags 0x%x used.idx %d",
 			 vring->avail->flags, vring->avail->idx,
 			 vring->used->flags, vring->used->idx);
-	if (type == VIRTIO_IF_TYPE_TAP)
+	if (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_TUN))
 	  {
 	    vlib_cli_output (vm, "    kickfd %d, callfd %d", vring->kick_fd,
 			     vring->call_fd);
@@ -401,7 +403,7 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 			 "    avail.flags 0x%x avail.idx %d used.flags 0x%x used.idx %d",
 			 vring->avail->flags, vring->avail->idx,
 			 vring->used->flags, vring->used->idx);
-	if (type == VIRTIO_IF_TYPE_TAP)
+	if (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_TUN))
 	  {
 	    vlib_cli_output (vm, "    kickfd %d, callfd %d", vring->kick_fd,
 			     vring->call_fd);
@@ -437,7 +439,7 @@ virtio_show (vlib_main_t * vm, u32 * hw_if_indices, u8 show_descr, u32 type)
 			   "    avail.flags 0x%x avail.idx %d used.flags 0x%x used.idx %d",
 			   vring->avail->flags, vring->avail->idx,
 			   vring->used->flags, vring->used->idx);
-	  if (type == VIRTIO_IF_TYPE_TAP)
+	  if (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_TUN))
 	    {
 	      vlib_cli_output (vm, "    kickfd %d, callfd %d", vring->kick_fd,
 			       vring->call_fd);
diff --git a/src/vnet/devices/virtio/virtio.h b/src/vnet/devices/virtio/virtio.h
index e28922bf654..3e8f9416483 100644
--- a/src/vnet/devices/virtio/virtio.h
+++ b/src/vnet/devices/virtio/virtio.h
@@ -80,11 +80,17 @@ typedef enum
 #define TX_QUEUE_ACCESS(X) (X/2)
 #define RX_QUEUE_ACCESS(X) (X/2)
 
+#define foreach_virtio_if_types \
+  _ (TAP, 1)                    \
+  _ (TUN, 2)                    \
+  _ (PCI, 3)
+
 typedef enum
 {
-  VIRTIO_IF_TYPE_TAP = 1,
-  VIRTIO_IF_TYPE_PCI,
-  VIRTIO_IF_N_TYPES,
+#define _(a, b) VIRTIO_IF_TYPE_##a = (1 << b),
+  foreach_virtio_if_types
+#undef _
+    VIRTIO_IF_N_TYPES = (1 << 4),
 } virtio_if_type_t;