/*
* Copyright (c) 2016 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.
*/
/**
* Midchain Adjacency sub-type. These adjs represent an L3 peer on a
* tunnel interface. The tunnel's adjacency is thus not the end of the chain,
* and needs to stack on/link to another chain (or portion of the graph) to
* reach the tunnel's destination.
*/
#ifndef __ADJ_MIDCHAIN_H__
#define __ADJ_MIDCHAIN_H__
#include <vnet/adj/adj.h>
/**
* @brief
* Convert an existing neighbour adjacency into a midchain
*
* @param adj_index
* The index of the neighbour adjacency.
*
* @param fixup
* The function that will be invoked at paket switch time to 'fixup'
* the rewrite applied with necessary per-packet info (i.e. length, checksums).
* @param fixup_data
* Context data set by the caller that is provided as an argument in the
* fixup function.
*
* @param flags
* Flags controlling the adjacency behaviour
*
* @param rewrite
* The rewrite.
*/
extern void adj_nbr_midchain_update_rewrite(adj_index_t adj_index,
adj_midchain_fixup_t fixup,
const void *fixup_data,
adj_flags_t flags,
u8 *rewrite);
/**
* @brief
* [re]stack a midchain. 'Stacking' is the act of forming parent-child
* relationships in the data-plane graph. Do NOT use this function to
* stack on a DPO type that might form a loop.
*
* @param adj_index
* The index of the midchain to stack
*
* @param dpo
* The parent DPO to stack onto (i.e. become a child of).
*/
extern void adj_nbr_midchain_stack(adj_index_t adj_index,
const dpo_id_t *dpo);
/**
* @brief
* [re]stack a midchain. 'Stacking' is the act of forming parent-child
* relationships in the data-plane graph. Since function performs recursive
* loop detection.
*
* @param adj_index
* The index of the midchain to stack
*
* @param fei
* The FIB entry to stack on
*
* @param fct
* The chain type to use from the fib entry fowarding
*/
extern void adj_nbr_midchain_stack_on_fib_entry(adj_index_t adj_index,
fib_node_index_t fei,
fib_forward_chain_type_t fct);
/**
* @brief
* unstack a midchain. This will break the chain between the midchain and
* the next graph section. This is a implemented as stack-on-drop
*
* @param adj_index
* The index of the midchain to stack
*/
extern void adj_nbr_midchain_unstack(adj_index_t adj_index);
/**
* @brief descend the FIB graph looking for loops
*
* @param ai
* The adj index to traverse
*
* @param entry_indicies)
* A pointer to a vector of FIB entries already visited.
*/
extern int adj_ndr_midchain_recursive_loop_detect(adj_index_t ai,
fib_node_index_t **entry_indicies);
/**
* @brief
* Module initialisation
*/
extern void adj_midchain_module_init(void);
/**
* @brief
* Format a midchain adjacency
*/
extern u8* format_adj_midchain(u8* s, va_list *ap);
/**
* @brief
* create/attach a midchain delegate and stack it on the prefix passed
* @param ai - the index of the adjacency to stack
* @param fib_index - The FIB index of the prefix on which to stack
* @param pfx - The prefix on which to stack
*/
extern void adj_midchain_delegate_stack(adj_index_t ai,
u32 fib_index,
const fib_prefix_t *pfx);
/**
* @brief restack a midchain delegate
*/
extern void adj_midchain_delegate_restack(adj_index_t ai);
/**
* @brief unstack a midchain delegate (this stacks it on a drop)
*/
extern void adj_midchain_delegate_unstack(adj_index_t ai);
#endif
