tap: add initial support for tun

Type: feature

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

4 files changed, 118 insertions, 22 deletions

diff --git a/src/vnet/devices/tap/cli.c b/src/vnet/devices/tap/cli.c
index 68b8cef2a21..40086a588aa 100644
--- a/src/vnet/devices/tap/cli.c
+++ b/src/vnet/devices/tap/cli.c
@@ -96,6 +96,8 @@ tap_create_command_fn (vlib_main_t * vm, unformat_input_t * input,
 	    args.tap_flags |= TAP_FLAG_PERSIST;
 	  else if (unformat (line_input, "attach"))
 	    args.tap_flags |= TAP_FLAG_ATTACH;
+	  else if (unformat (line_input, "tun"))
+	    args.tap_flags |= TAP_FLAG_TUN;
 	  else if (unformat (line_input, "hw-addr %U",
 			     unformat_ethernet_address, args.mac_addr.bytes))
 	    args.mac_addr_set = 1;
@@ -136,7 +138,7 @@ VLIB_CLI_COMMAND (tap_create_command, static) = {
     "[host-ip6-addr <ip6-addr>] [host-ip4-gw <ip4-addr>] "
     "[host-ip6-gw <ip6-addr>] [host-mac-addr <host-mac-address>] "
     "[host-if-name <name>] [host-mtu-size <size>] [no-gso|gso|csum-offload] "
-    "[persist] [attach]",
+    "[persist] [attach] [tun]",
   .function = tap_create_command_fn,
 };
 /* *INDENT-ON* */
@@ -306,6 +308,56 @@ VLIB_CLI_COMMAND (tap_show_command, static) = {
 };
 /* *INDENT-ON* */
 
+static clib_error_t *
+tun_show_command_fn (vlib_main_t * vm, unformat_input_t * input,
+		     vlib_cli_command_t * cmd)
+{
+  virtio_main_t *mm = &virtio_main;
+  virtio_if_t *vif;
+  vnet_main_t *vnm = vnet_get_main ();
+  int show_descr = 0;
+  clib_error_t *error = 0;
+  u32 hw_if_index, *hw_if_indices = 0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat
+	  (input, "%U", unformat_vnet_hw_interface, vnm, &hw_if_index))
+	vec_add1 (hw_if_indices, hw_if_index);
+      else if (unformat (input, "descriptors"))
+	show_descr = 1;
+      else
+	{
+	  error = clib_error_return (0, "unknown input `%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+
+  if (vec_len (hw_if_indices) == 0)
+    {
+      /* *INDENT-OFF* */
+      pool_foreach (vif, mm->interfaces,
+          vec_add1 (hw_if_indices, vif->hw_if_index);
+      );
+      /* *INDENT-ON* */
+    }
+
+  virtio_show (vm, hw_if_indices, show_descr, VIRTIO_IF_TYPE_TUN);
+
+done:
+  vec_free (hw_if_indices);
+  return error;
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (tun_show_command, static) = {
+  .path = "show tun",
+  .short_help = "show tun {<interface>] [descriptors]",
+  .function = tun_show_command_fn,
+};
+/* *INDENT-ON* */
+
 clib_error_t *
 tap_cli_init (vlib_main_t * vm)
 {
diff --git a/src/vnet/devices/tap/tap.c b/src/vnet/devices/tap/tap.c
index 59c1531a0d2..3b67b53de4a 100644
--- a/src/vnet/devices/tap/tap.c
+++ b/src/vnet/devices/tap/tap.c
@@ -57,6 +57,14 @@ tap_main_t tap_main;
       goto error; \
     }
 
+  /* *INDENT-OFF* */
+VNET_HW_INTERFACE_CLASS (tun_device_hw_interface_class, static) =
+{
+  .name = "tun-device",
+  .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
+};
+  /* *INDENT-ON* */
+
 static u32
 virtio_eth_flag_change (vnet_main_t * vnm, vnet_hw_interface_t * hi,
 			u32 flags)
@@ -134,7 +142,7 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args)
   vnet_hw_interface_t *hw;
   int i;
   int old_netns_fd = -1;
-  struct ifreq ifr = {.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR };
+  struct ifreq ifr = {.ifr_flags = IFF_NO_PI | IFF_VNET_HDR };
   struct ifreq get_ifr = {.ifr_flags = 0 };
   size_t hdrsz;
   struct vhost_memory *vhost_mem = 0;
@@ -168,7 +176,19 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args)
     }
 
   pool_get_zero (vim->interfaces, vif);
-  vif->type = VIRTIO_IF_TYPE_TAP;
+
+  if (args->tap_flags & TAP_FLAG_TUN)
+    {
+      vif->type = VIRTIO_IF_TYPE_TUN;
+      ifr.ifr_flags |= IFF_TUN;
+      args->tap_flags &= ~(TAP_FLAG_GSO | TAP_FLAG_CSUM_OFFLOAD);
+    }
+  else
+    {
+      vif->type = VIRTIO_IF_TYPE_TAP;
+      ifr.ifr_flags |= IFF_TAP;
+    }
+
   vif->dev_instance = vif - vim->interfaces;
   vif->id = args->id;
   vif->num_txqs = thm->n_vlib_mains;
@@ -404,14 +424,17 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args)
 	}
     }
 
-  if (ethernet_mac_address_is_zero (args->host_mac_addr.bytes))
-    ethernet_mac_address_generate (args->host_mac_addr.bytes);
-  args->error = vnet_netlink_set_link_addr (vif->ifindex,
-					    args->host_mac_addr.bytes);
-  if (args->error)
+  if (vif->type == VIRTIO_IF_TYPE_TAP)
     {
-      args->rv = VNET_API_ERROR_NETLINK_ERROR;
-      goto error;
+      if (ethernet_mac_address_is_zero (args->host_mac_addr.bytes))
+	ethernet_mac_address_generate (args->host_mac_addr.bytes);
+      args->error = vnet_netlink_set_link_addr (vif->ifindex,
+						args->host_mac_addr.bytes);
+      if (args->error)
+	{
+	  args->rv = VNET_API_ERROR_NETLINK_ERROR;
+	  goto error;
+	}
     }
 
   if (args->host_bridge)
@@ -615,11 +638,13 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args)
       _IOCTL (fd, VHOST_NET_SET_BACKEND, &file);
     }
 
-  if (!args->mac_addr_set)
-    ethernet_mac_address_generate (args->mac_addr.bytes);
-
-  clib_memcpy (vif->mac_addr, args->mac_addr.bytes, 6);
+  if (vif->type == VIRTIO_IF_TYPE_TAP)
+    {
+      if (!args->mac_addr_set)
+	ethernet_mac_address_generate (args->mac_addr.bytes);
 
+      clib_memcpy (vif->mac_addr, args->mac_addr.bytes, 6);
+    }
   vif->host_if_name = format (0, "%s%c", host_if_name, 0);
   vif->net_ns = format (0, "%s%c", args->host_namespace, 0);
   vif->host_bridge = format (0, "%s%c", args->host_bridge, 0);
@@ -632,17 +657,28 @@ tap_create_if (vlib_main_t * vm, tap_create_if_args_t * args)
   if (args->host_ip6_prefix_len)
     clib_memcpy (&vif->host_ip6_addr, &args->host_ip6_addr, 16);
 
-  args->error = ethernet_register_interface (vnm, virtio_device_class.index,
-					     vif->dev_instance,
-					     vif->mac_addr,
-					     &vif->hw_if_index,
-					     virtio_eth_flag_change);
-  if (args->error)
+  if (vif->type != VIRTIO_IF_TYPE_TUN)
     {
-      args->rv = VNET_API_ERROR_INVALID_REGISTRATION;
-      goto error;
+      args->error =
+	ethernet_register_interface (vnm, virtio_device_class.index,
+				     vif->dev_instance, vif->mac_addr,
+				     &vif->hw_if_index,
+				     virtio_eth_flag_change);
+      if (args->error)
+	{
+	  args->rv = VNET_API_ERROR_INVALID_REGISTRATION;
+	  goto error;
+	}
+
     }
+  else
+    {
+      vif->hw_if_index = vnet_register_interface
+	(vnm, virtio_device_class.index,
+	 vif->dev_instance /* device instance */ ,
+	 tun_device_hw_interface_class.index, vif->dev_instance);
 
+    }
   tm->tap_ids = clib_bitmap_set (tm->tap_ids, vif->id, 1);
   sw = vnet_get_hw_sw_interface (vnm, vif->hw_if_index);
   vif->sw_if_index = sw->sw_if_index;
@@ -746,6 +782,9 @@ tap_csum_offload_enable_disable (vlib_main_t * vm, u32 sw_if_index,
 
   vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
 
+  if (vif->type == VIRTIO_IF_TYPE_TUN)
+    return VNET_API_ERROR_UNIMPLEMENTED;
+
   const unsigned int csum_offload_on = TUN_F_CSUM;
   const unsigned int csum_offload_off = 0;
   unsigned int offload = enable_disable ? csum_offload_on : csum_offload_off;
@@ -801,6 +840,9 @@ tap_gso_enable_disable (vlib_main_t * vm, u32 sw_if_index, int enable_disable)
 
   vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
 
+  if (vif->type == VIRTIO_IF_TYPE_TUN)
+    return VNET_API_ERROR_UNIMPLEMENTED;
+
   const unsigned int gso_on = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6;
   const unsigned int gso_off = 0;
   unsigned int offload = enable_disable ? gso_on : gso_off;
diff --git a/src/vnet/devices/tap/tap.h b/src/vnet/devices/tap/tap.h
index 5d087ad9da5..c1ac7a61229 100644
--- a/src/vnet/devices/tap/tap.h
+++ b/src/vnet/devices/tap/tap.h
@@ -35,6 +35,7 @@ typedef struct
 #define TAP_FLAG_CSUM_OFFLOAD (1 << 1)
 #define TAP_FLAG_PERSIST (1 << 2)
 #define TAP_FLAG_ATTACH (1 << 3)
+#define TAP_FLAG_TUN (1 << 4)
   u8 *host_namespace;
   u8 *host_if_name;
   mac_address_t host_mac_addr;
diff --git a/src/vnet/devices/tap/tapv2.api b/src/vnet/devices/tap/tapv2.api
index ccbbe158160..9113458852f 100644
--- a/src/vnet/devices/tap/tapv2.api
+++ b/src/vnet/devices/tap/tapv2.api
@@ -30,6 +30,7 @@ enum tap_flags {
         TAP_FLAG_CSUM_OFFLOAD = 2,
 	TAP_FLAG_PERSIST = 4,
 	TAP_FLAG_ATTACH = 8,
+	TAP_FLAG_TUN = 16,
 };
 
 /** \brief Initialize a new tap interface with the given parameters