/*
 * Copyright (c) 2018 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * The IPIP module implements IP{v4,v6} over IP{v4,v6} tunnelling as
 * described in RFC2473 and to some extent the largely historical
 * RFC1853.  The module also supports an IPv4 over IPv6 automatic
 * tunnelling mechanism called 6RD (RFC5969).
 *
 * The IPIP API module supports a CRD model for adding, deleting and
 * listing tunnels. A tunnel is represented as an interface in
 * VPP. The "handle" representing a tunnel is the sw_if_index.  As any
 * interface, the user must configure an IPv4 and/or IPv6 address on
 * the interface. This is the inner or payload protocol.
 *
 * Tunnel MTU: The tunnel MTU (the payload MTU) is configurable per
 * protocol. If a tunnel MTU is larger than the path MTU, the outer
 * packet will be fragmented. Fragmentation support is configurable,
 * as it can have severe performance issues, and might be used as an
 * attack vector (the remote side must reassemble.)
 *
 * Traffic class / TOS field can either be configured to a fixed
 * value, or can be copied from the inner to the outer header.
 * (For now we have stolen ~0 to indicate copy).
 *
 * Note:
 *
 * - The Tunnel encapsulation limit described in RFC2473 is not
 *   implemented.
 *
 * - ICMP proxying, as in a tunnel head-end receiving ICMP erors on
 *   the outer packet is currently not relayed to the original source
 *   of the packet.
 *
 * - PMTUD / MTU probing and tunnel keepalives are not yet implemented.
 *
 */

option version = "1.2.0";
import "vnet/interface_types.api";
import "vnet/ip/ip_types.api";

/**
 * An IP{v4,v6} over IP{v4,v6} tunnel.
 */
typedef ipip_tunnel
{
  u32 instance; /* If non-~0, specifies a custom dev instance */
  vl_api_address_t src;
  vl_api_address_t dst;
  vl_api_interface_index_t sw_if_index; /* ignored on create, set in
					   details/dump */
  u32 table_id;
  u8 tc_tos; /* If ~0, the TOS/TC value is copied from
                inner packet, otherwise set to value */
};

/**
 * Create an IP{v4,v6} over IP{v4,v6} tunnel.
 */
define ipip_add_tunnel
{
  u32 client_index;
  u32 context;
  vl_api_ipip_tunnel_t tunnel;
};

define ipip_add_tunnel_reply
{
  u32 context;
  i32 retval;
  vl_api_interface_index_t sw_if_index;
};

/**
 * Delete an IP{v4,v6} over IP{v4,v6} tunnel.
 */
autoreply define ipip_del_tunnel
{
  u32 client_index;
  u32 context;
  vl_api_interface_index_t sw_if_index;
};

/**
 * Create an IPv4 over IPv6 automatic tunnel (6RD)
 */
define ipip_6rd_add_tunnel
{
  u32 client_index;
  u32 context;
  u32 ip6_table_id;
  u32 ip4_table_id;
  vl_api_ip6_prefix_t ip6_prefix;
  vl_api_ip4_prefix_t ip4_prefix;
  vl_api_ip4_address_t ip4_src;
  bool security_check;
  u8 tc_tos; /* If ~0, the TOS/TC value is copied from
                inner packet, otherwise set to value */
};

define ipip_6rd_add_tunnel_reply
{
  u32 context;
  i32 retval;
  vl_api_interface_index_t sw_if_index;
};

/**
 * Delete an IPv4 over IPv6 automatic tunnel (6RD)
 */
autoreply define ipip_6rd_del_tunnel
{
  u32 client_index;
  u32 context;
  vl_api_interface_index_t sw_if_index;
};

/**
 * List all IPIP tunnels
 */
define ipip_tunnel_dump
{
  u32 client_index;
  u32 context;
  vl_api_interface_index_t sw_if_index;
};

define ipip_tunnel_details
{
  u32 context;
  vl_api_ipip_tunnel_t tunnel;
};