/*
 * Copyright (c) 2021 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.
 */

#ifndef __HICN_ROUTE__
#define __HICN_ROUTE__

#include <vlib/vlib.h>
#include <vppinfra/error.h>
#include "hicn.h"
#include "faces/face.h"

/**
 * @file route.h
 *
 * hICN uses a specific vrf to install the routes for a prefix has been enabled
 * to be hicn. It considers the vrf 0 (the default vrf) as the dominating vrf
 * on which every route is stored. Enabling a prefix to be hICN will copy all
 * the routes in the vrf 0 for the given prefi, in the vrf HICN. Every
 * modification made on the vrf 0 on an hICN enabled prefix is reflected in the
 * vrf hICN (through the use of the fib entry tracking functionality).
 * Moreover, we use the lookup in the vrf hICN as a way for punting packet that
 * must be processed as hICN. The implementation will install a special dpo as
 * a single next hop for the vpp load balancer for each entry in the vrf hICN
 * that we enabled. Such dpo will have two purposes: 1) to punt packets to the
 * hICN forwarding pipeline, 2) to point to the righe strategy (the dpoi_index
 * will be an index to the strategy context while the dpoi_type will be an
 * index to the strategy vft).
 *
 * Additionally, hICN assign each interface to the vrf hICN; this is required
 * for the interest lookup. Vpp performs a lookup in the vrf assigned to the
 * interface, therefore if an interface is not assigned to the hICN vrf, the
 * lookup will be done on the vrf 0 and the packet won't be processed through
 * the hicn forwarding pipeline.
 */

/*
 * Adding each interface to the vrf hICN has the side effect that to ping you
 * need to specify the vrf hICN in the command.
 */

extern fib_source_t hicn_fib_src;

extern dpo_type_t udp_encap_dpo_types[FIB_PROTOCOL_MAX];

/**
 * @Brief Return the hicn_dpo corresponding to the prefix in teh vrf HICN
 *
 * @param prefix Prefix for which we want to retrieve the hICN dpo
 * @param hicn_dpo return value with the hicn_dpo
 * @param fib_index return value with the fib index corresponding to the prefix
 */
int hicn_route_get_dpo (const fib_prefix_t *prefix, const dpo_id_t **hicn_dpo,
			u32 *fib_index);

/**
 * @Brief Set the strategy for a given prefix
 *
 * @param prefix Prefix for which we set the strategy
 * @param stretegy_id Index of the strategy to set
 */
int hicn_route_set_strategy (fib_prefix_t *prefix, u32 strategy_id);

/**
 * @Brief Helper to add an adj nex hop in the vrf 0. If there are no entries in
 * the vrf 0 that matches with the prefix (epm), a new one is created.
 *
 * @param fib_proto FIB_PROTOCOL_IP6 or FIB_PROTOCOL_IP4 (mpls not supported)
 * @param rpfx Prefix for which to add a next hop
 * @param nh Next hop to add
 * @param sw_if Software interface index to add in the next hop
 */
int ip_nh_adj_add_del_helper (fib_protocol_t fib_proto,
			      const fib_prefix_t *rpfx, ip46_address_t *nh,
			      u32 sw_if, u8 is_add);

/**
 * @Brief Helper to add an udp-tunnel nex hop in the vrf 0. If there are no
 * entries in the vrf 0 that matches with the prefix (epm), a new one is
 * created.
 *
 * @param fib_proto FIB_PROTOCOL_IP6 or FIB_PROTOCOL_IP4 (mpls not supported)
 * @param rpfx Prefix for which to add a next hop
 * @param uei The UDP ENCAP ID
 * @param proto The payload proto for this encap
 */
int ip_nh_udp_tunnel_add_del_helper (fib_protocol_t fib_proto,
				     const fib_prefix_t *rpfx, u32 uei,
				     dpo_proto_t proto, u8 is_add);

/**
 * @Brief Enable an hICN for an ip prefix
 *
 * @param prefix Prefix for which we enable hICN
 * @return HICN_ERROR_NONE if hICN was enabled on the prefix
 * HICN_ERROR_ROUTE_NO_LD if the first dpo for the fib entry corresponding to
 * the prefix is not a load_balancer HICN_ERROR_ROUTE_DPO_NO_HICN if the
 * loadbalancer in the vrf HICN already contains a dpo which is not an hICN one
 * HICN_ERROR_ROUTE_MLT_LD if there are more than a dpo in the vpp loadbalancer
 */
int hicn_route_enable (const fib_prefix_t *prefix,
		       fib_node_index_t *hicn_fib_node_index,
		       hicn_face_id_t **vec_faces);

/**
 * @Brief Disable an hICN for an ip prefix. If hICN wasn't enable on the prefix
 * nothing happens and it returns HICN_ERROR_ROUTE_NOT_FOUND
 *
 * @param prefix Prefix for which we disable hICN
 */
int hicn_route_disable (fib_prefix_t *prefix);

/* Init route internal strustures */
void hicn_route_init ();
#endif /* //__HICN_ROUTE__ */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables: eval: (c-set-style "gnu") End:
 */