/*
 * 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.
 */
/*
 * ip/ip6.h: ip6 main include file
 *
 * Copyright (c) 2008 Eliot Dresselhaus
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef included_ip_ip6_h
#define included_ip_ip6_h

#include <vlib/mc.h>
#include <vlib/buffer.h>
#include <vnet/ethernet/packet.h>
#include <vnet/ip/ip6_packet.h>
#include <vnet/ip/ip6_hop_by_hop_packet.h>
#include <vnet/ip/lookup.h>
#include <stdbool.h>
#include <vppinfra/bihash_24_8.h>
#include <vppinfra/bihash_template.h>

/*
 * Default size of the ip6 fib hash table
 */
#define IP6_FIB_DEFAULT_HASH_NUM_BUCKETS (64 * 1024)
#define IP6_FIB_DEFAULT_HASH_MEMORY_SIZE (32<<20)

typedef struct
{
  ip6_address_t addr;
  u32 dst_address_length;
  u32 vrf_index;
} ip6_fib_key_t;

typedef struct
{
  /* Table ID (hash key) for this FIB. */
  u32 table_id;

  /* Index into FIB vector. */
  u32 index;

  /* flow hash configuration */
  flow_hash_config_t flow_hash_config;
} ip6_fib_t;

struct ip6_main_t;

typedef void (ip6_add_del_interface_address_function_t)
  (struct ip6_main_t * im,
   uword opaque,
   u32 sw_if_index,
   ip6_address_t * address,
   u32 address_length, u32 if_address_index, u32 is_del);

typedef struct
{
  ip6_add_del_interface_address_function_t *function;
  uword function_opaque;
} ip6_add_del_interface_address_callback_t;

/**
 * Enumeration of the FIB table instance types
 */
typedef enum ip6_fib_table_instance_type_t_
{
    /**
     * This table stores the routes that are used to forward traffic.
     * The key is the prefix, the result the adjacnecy to forward on.
     */
  IP6_FIB_TABLE_FWDING,
    /**
     * The table that stores ALL routes learned by the DP.
     * Some of these routes may not be ready to install in forwarding
     * at a given time.
     * The key in this table is the prefix, the result is the fib_entry_t
     */
  IP6_FIB_TABLE_NON_FWDING,
} ip6_fib_table_instance_type_t;

#define IP6_FIB_NUM_TABLES (IP6_FIB_TABLE_NON_FWDING+1)

/**
 * A represenation of a single IP6 table
 */
typedef struct ip6_fib_table_instance_t_
{
  /* The hash table */
  BVT (clib_bihash) ip6_hash;

  /* bitmap / refcounts / vector of mask widths to search */
  uword *non_empty_dst_address_length_bitmap;
  u8 *prefix_lengths_in_search_order;
  i32 dst_address_length_refcounts[129];
} ip6_fib_table_instance_t;

typedef struct ip6_main_t
{
  /**
   * The two FIB tables; fwding and non-fwding
   */
  ip6_fib_table_instance_t ip6_table[IP6_FIB_NUM_TABLES];

  ip_lookup_main_t lookup_main;

  /* Pool of FIBs. */
  struct fib_table_t_ *fibs;

  /* Network byte orders subnet mask for each prefix length */
  ip6_address_t fib_masks[129];

  /* Table index indexed by software interface. */
  u32 *fib_index_by_sw_if_index;

  /* IP6 enabled count by software interface */
  u8 *ip_enabled_by_sw_if_index;

  /* Hash table mapping table id to fib index.
     ID space is not necessarily dense; index space is dense. */
  uword *fib_index_by_table_id;

  /* Hash table mapping interface rewrite adjacency index by sw if index. */
  uword *interface_route_adj_index_by_sw_if_index;

  /* Functions to call when interface address changes. */
    ip6_add_del_interface_address_callback_t
    * add_del_interface_address_callbacks;

  /* Template used to generate IP6 neighbor solicitation packets. */
  vlib_packet_template_t discover_neighbor_packet_template;

  /* ip6 lookup table config parameters */
  u32 lookup_table_nbuckets;
  uword lookup_table_size;

  /* Seed for Jenkins hash used to compute ip6 flow hash. */
  u32 flow_hash_seed;

  struct
  {
    /* TTL to use for host generated packets. */
    u8 ttl;

    u8 pad[3];
  } host_config;

  /* HBH processing enabled? */
  u8 hbh_enabled;
} ip6_main_t;

/* Global ip6 main structure. */
extern ip6_main_t ip6_main;

/* Global ip6 input node.  Errors get attached to ip6 input node. */
extern vlib_node_registration_t ip6_input_node;
extern vlib_node_registration_t ip6_rewrite_node;
extern vlib_node_registration_t ip6_rewrite_local_node;
extern vlib_node_registration_t ip6_discover_neighbor_node;
extern vlib_node_registration_t ip6_glean_node;
extern vlib_node_registration_t ip6_midchain_node;

extern vlib_node_registration_t ip6_icmp_neighbor_discovery_event_node;

/* ipv6 neighbor discovery - timer/event types */
typedef enum
{
  ICMP6_ND_EVENT_INIT,
} ip6_icmp_neighbor_discovery_event_type_t;

typedef union
{
  u32 add_del_swindex;
  struct
  {
    u32 up_down_swindex;
    u32 fib_index;
  } up_down_event;
} ip6_icmp_neighbor_discovery_event_data_t;

always_inline uword
ip6_destination_matches_route (const ip6_main_t * im,
			       const ip6_address_t * key,
			       const ip6_address_t * dest, uword dest_length)
{
  int i;
  for (i = 0; i < ARRAY_LEN (key->as_uword); i++)
    {
      if ((key->as_uword[i] ^ dest->as_uword[i]) & im->
	  fib_masks[dest_length].as_uword[i])
	return 0;
    }
  return 1;
}

always_inline uword
ip6_destination_matches_interface (ip6_main_t * im,
				   ip6_address_t * key,
				   ip_interface_address_t * ia)
{
  ip6_address_t *a = ip_interface_address_get_address (&im->lookup_main, ia);
  return ip6_destination_matches_route (im, key, a, ia->address_length);
}

/* As above but allows for unaligned destinations (e.g. works right from IP header of packet). */
always_inline uword
ip6_unaligned_destination_matches_route (ip6_main_t * im,
					 ip6_address_t * key,
					 ip6_address_t * dest,
					 uword dest_length)
{
  int i;
  for (i = 0; i < ARRAY_LEN (key->as_uword); i++)
    {
      if ((clib_mem_unaligned (&key->as_uword[i], uword) ^ dest->as_uword[i])
	  & im->fib_masks[dest_length].as_uword[i])
	return 0;
    }
  return 1;
}

always_inline int
ip6_src_address_for_packet (ip_lookup_main_t * lm,
			    u32 sw_if_index, ip6_address_t * src)
{
  u32 if_add_index = lm->if_address_pool_index_by_sw_if_index[sw_if_index];
  if (PREDICT_TRUE (if_add_index != ~0))
    {
      ip_interface_address_t *if_add =
	pool_elt_at_index (lm->if_address_pool, if_add_index);
      ip6_address_t *if_ip = ip_interface_address_get_address (lm, if_add);
      *src = *if_ip;
      return (0);
    }
  else
    {
      src->as_u64[0] = 0;
      src->as_u64[1] = 0;
    }
  return (!0);
}

/* Find interface address which matches destination. */
always_inline ip6_address_t *
ip6_interface_address_matching_destination (ip6_main_t * im,
					    ip6_address_t * dst,
					    u32 sw_if_index,
					    ip_interface_address_t **
					    result_ia)
{
  ip_lookup_main_t *lm = &im->lookup_main;
  ip_interface_address_t *ia;
  ip6_address_t *result = 0;

  /* *INDENT-OFF* */
  foreach_ip_interface_address (lm, ia, sw_if_index,
                                1 /* honor unnumbered */,
  ({
    ip6_address_t * a = ip_interface_address_get_address (lm, ia);
    if (ip6_destination_matches_route (im, dst, a, ia->address_length))
      {
	result = a;
	break;
      }
  }));
  /* *INDENT-ON* */
  if (result_ia)
    *result_ia = result ? ia : 0;
  return result;
}

clib_error_t *ip6_add_del_interface_address (vlib_main_t * vm,
					     u32 sw_if_index,
					     ip6_address_t * address,
					     u32 address_length, u32 is_del);
void ip6_sw_interface_enable_disable (u32 sw_if_index, u32 is_enable);

int ip6_address_compare (ip6_address_t * a1, ip6_address_t * a2);

clib_error_t *ip6_probe_neighbor (vlib_main_t * vm, ip6_address_t * dst,
				  u32 sw_if_index);

clib_error_t *ip6_set_neighbor_limit (u32 neighbor_limit);

uword
ip6_udp_register_listener (vlib_main_t * vm,
			   u16 dst_port, u32 next_node_index);

u16 ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
				       ip6_header_t * ip0,
				       int *bogus_lengthp);

void ip6_register_protocol (u32 protocol, u32 node_index);

serialize_function_t serialize_vnet_ip6_main, unserialize_vnet_ip6_main;

void ip6_ethernet_update_adjacency (vnet_main_t * vnm,
				    u32 sw_if_index, u32 ai);

int
vnet_set_ip6_ethernet_neighbor (vlib_main_t * vm,
				u32 sw_if_index,
				ip6_address_t * a,
				u8 * link_layer_address,
				uword n_bytes_link_layer_address,
				int is_static);
int
vnet_unset_ip6_ethernet_neighbor (vlib_main_t * vm,
				  u32 sw_if_index,
				  ip6_address_t * a,
				  u8 * link_layer_address,
				  uword n_bytes_link_layer_address);

void
ip6_link_local_address_from_ethernet_mac_address (ip6_address_t * ip,
						  u8 * mac);

void
ip6_ethernet_mac_address_from_link_local_address (u8 * mac,
						  ip6_address_t * ip);

int vnet_set_ip6_flow_hash (u32 table_id,
			    flow_hash_config_t flow_hash_config);

int
ip6_neighbor_ra_config (vlib_main_t * vm, u32 sw_if_index,
			u8 suppress, u8 managed, u8 other,
			u8 ll_option, u8 send_unicast, u8 cease,
			u8 use_lifetime, u32 lifetime,
			u32 initial_count, u32 initial_interval,
			u32 max_interval, u32 min_interval, u8 is_no);

int
ip6_neighbor_ra_prefix (vlib_main_t * vm, u32 sw_if_index,
			ip6_address_t * prefix_addr, u8 prefix_len,
			u8 use_default, u32 val_lifetime, u32 pref_lifetime,
			u8 no_advertise, u8 off_link, u8 no_autoconfig,
			u8 no_onlink, u8 is_no);


clib_error_t *enable_ip6_interface (vlib_main_t * vm, u32 sw_if_index);

clib_error_t *disable_ip6_interface (vlib_main_t * vm, u32 sw_if_index);

int ip6_interface_enabled (vlib_main_t * vm, u32 sw_if_index);

clib_error_t *set_ip6_link_local_address (vlib_main_t * vm,
					  u32 sw_if_index,
					  ip6_address_t * address,
					  u8 address_length);

void vnet_register_ip6_neighbor_resolution_event (vnet_main_t * vnm,
						  void *address_arg,
						  uword node_index,
						  uword type_opaque,
						  uword data);

int vnet_add_del_ip6_nd_change_event (vnet_main_t * vnm,
				      void *data_callback,
				      u32 pid,
				      void *address_arg,
				      uword node_index,
				      uword type_opaque,
				      uword data, int is_add);

int vnet_ip6_nd_term (vlib_main_t * vm,
		      vlib_node_runtime_t * node,
		      vlib_buffer_t * p0,
		      ethernet_header_t * eth,
		      ip6_header_t * ip,
		      u32 sw_if_index, u16 bd_index, u8 shg);

int vnet_set_ip6_classify_intfc (vlib_main_t * vm, u32 sw_if_index,
				 u32 table_index);
extern vlib_node_registration_t ip6_lookup_node;

/* Compute flow hash.  We'll use it to select which Sponge to use for this
   flow.  And other things. */
always_inline u32
ip6_compute_flow_hash (const ip6_header_t * ip,
		       flow_hash_config_t flow_hash_config)
{
  tcp_header_t *tcp = (void *) (ip + 1);
  u64 a, b, c;
  u64 t1, t2;
  uword is_tcp_udp = (ip->protocol == IP_PROTOCOL_TCP
		      || ip->protocol == IP_PROTOCOL_UDP);

  t1 = (ip->src_address.as_u64[0] ^ ip->src_address.as_u64[1]);
  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_ADDR) ? t1 : 0;

  t2 = (ip->dst_address.as_u64[0] ^ ip->dst_address.as_u64[1]);
  t2 = (flow_hash_config & IP_FLOW_HASH_DST_ADDR) ? t2 : 0;

  a = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t2 : t1;
  b = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t1 : t2;
  b ^= (flow_hash_config & IP_FLOW_HASH_PROTO) ? ip->protocol : 0;

  t1 = is_tcp_udp ? tcp->ports.src : 0;
  t2 = is_tcp_udp ? tcp->ports.dst : 0;

  t1 = (flow_hash_config & IP_FLOW_HASH_SRC_PORT) ? t1 : 0;
  t2 = (flow_hash_config & IP_FLOW_HASH_DST_PORT) ? t2 : 0;

  c = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ?
    ((t1 << 16) | t2) : ((t2 << 16) | t1);

  hash_mix64 (a, b, c);
  return (u32) c;
}

/*
 * Hop-by-Hop handling
 */
typedef struct
{
  /* Array of function pointers to HBH option handling routines */
  int (*options[256]) (vlib_buffer_t * b, ip6_header_t * ip,
		       ip6_hop_by_hop_option_t * opt);
  u8 *(*trace[256]) (u8 * s, ip6_hop_by_hop_option_t * opt);
  uword next_override;
} ip6_hop_by_hop_main_t;

extern ip6_hop_by_hop_main_t ip6_hop_by_hop_main;

int ip6_hbh_register_option (u8 option,
			     int options (vlib_buffer_t * b,
					  ip6_header_t * ip,
					  ip6_hop_by_hop_option_t * opt),
			     u8 * trace (u8 * s,
					 ip6_hop_by_hop_option_t * opt));
int ip6_hbh_unregister_option (u8 option);
void ip6_hbh_set_next_override (uword next);

/* Flag used by IOAM code. Classifier sets it pop-hop-by-hop checks it */
#define OI_DECAP   0x80000000

#endif /* included_ip_ip6_h */

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