/*
 * Copyright (c) 2017-2019 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.
 */

#include <vnet/ip/ip6_packet.h>

#include "interest_pcslookup.h"
#include "mgmt.h"
#include "parser.h"
#include "infra.h"
#include "strategy_dpo_manager.h"
#include "error.h"
#include "state.h"

/**
 * @FILE This node performs a lookup in the PIT and CS for a received interest packet.
 *
 * This node passes the packet to the interest-hitpit and interest-hitcs nodes
 * when there is a hit in the pit or content store, respectively.
 */

/* Functions declarations */

/* packet trace format function */
static u8 *hicn_interest_pcslookup_format_trace (u8 * s, va_list * args);


/* Stats string values */
static char *hicn_interest_pcslookup_error_strings[] = {
#define _(sym, string) string,
  foreach_hicnfwd_error
#undef _
};

vlib_node_registration_t hicn_interest_pcslookup_node;

/*
 * ICN forwarder node for interests: handling of Interests delivered based on
 * ACL. - 1 packet at a time - ipv4/tcp ipv6/tcp
 */
static uword
hicn_interest_pcslookup_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
				 vlib_frame_t * frame)
{
  u32 n_left_from, *from, *to_next;
  hicn_interest_pcslookup_next_t next_index;
  hicn_interest_pcslookup_runtime_t *rt;
  vl_api_hicn_api_node_stats_get_reply_t stats = { 0 };
  int ret;

  rt = vlib_node_get_runtime_data (vm, hicn_interest_pcslookup_node.index);

  if (PREDICT_FALSE (rt->pitcs == NULL))
    {
      rt->pitcs = &hicn_main.pitcs;
    }
  from = vlib_frame_vector_args (frame);
  n_left_from = frame->n_vectors;
  next_index = node->cached_next_index;

  while (n_left_from > 0)
    {
      u32 n_left_to_next;
      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
      while (n_left_from > 0 && n_left_to_next > 0)
	{
	  vlib_buffer_t *b0;
	  u8 isv6;
	  u8 *nameptr;
	  u16 namelen;
	  u32 bi0;
	  u32 next0 = HICN_INTEREST_PCSLOOKUP_NEXT_ERROR_DROP;
	  u64 name_hash = 0;
	  hicn_name_t name;
	  hicn_header_t *hicn0;
	  u32 node_id0 = 0;
	  u8 dpo_ctx_id0 = 0;
	  u8 vft_id0 = 0;
	  u8 is_cs0 = 0;
	  u8 hash_entry_id = 0;
	  u8 bucket_is_overflown = 0;
	  u32 bucket_id = ~0;

	  /* Prefetch for next iteration. */
	  if (n_left_from > 1)
	    {
	      vlib_buffer_t *b1;
	      b1 = vlib_get_buffer (vm, from[1]);
	      CLIB_PREFETCH (b1, CLIB_CACHE_LINE_BYTES, STORE);
	      CLIB_PREFETCH (b1->data, CLIB_CACHE_LINE_BYTES, LOAD);
	    }
	  /* Dequeue a packet buffer */
	  bi0 = from[0];
	  from += 1;
	  n_left_from -= 1;
	  to_next[0] = bi0;
	  to_next += 1;
	  n_left_to_next -= 1;

	  b0 = vlib_get_buffer (vm, bi0);
	  ret = hicn_interest_parse_pkt (b0, &name, &namelen, &hicn0, &isv6);

	  if (PREDICT_TRUE (ret == HICN_ERROR_NONE))
	    {
	      next0 =
		isv6 ? HICN_INTEREST_PCSLOOKUP_NEXT_V6_LOOKUP :
		HICN_INTEREST_PCSLOOKUP_NEXT_V4_LOOKUP;
	    }
	  nameptr = (u8 *) (&name);
	  stats.pkts_processed++;

	  if (PREDICT_FALSE (ret != HICN_ERROR_NONE ||
			     hicn_hashtb_fullhash (nameptr, namelen,
						   &name_hash) !=
			     HICN_ERROR_NONE))
	    {
	      next0 = HICN_INTEREST_PCSLOOKUP_NEXT_ERROR_DROP;
	    }
	  else
	    {
	      if (hicn_hashtb_lookup_node (rt->pitcs->pcs_table, nameptr,
					   namelen, name_hash,
					   0 /* is_data */ , &node_id0,
					   &dpo_ctx_id0, &vft_id0, &is_cs0,
					   &hash_entry_id, &bucket_id,
					   &bucket_is_overflown) ==
		  HICN_ERROR_NONE)
		{
		  next0 =
		    HICN_INTEREST_PCSLOOKUP_NEXT_INTEREST_HITPIT + is_cs0;
		}
	      stats.pkts_interest_count++;
	    }

	  hicn_store_internal_state (b0, name_hash, node_id0, dpo_ctx_id0,
				     vft_id0, hash_entry_id, bucket_id,
				     bucket_is_overflown);

	  /* Maybe trace */
	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
			     (b0->flags & VLIB_BUFFER_IS_TRACED)))
	    {
	      hicn_interest_pcslookup_trace_t *t =
		vlib_add_trace (vm, node, b0, sizeof (*t));
	      t->pkt_type = HICN_PKT_TYPE_INTEREST;
	      t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
	      t->next_index = next0;
	    }
	  /*
	   * Verify speculative enqueue, maybe switch current
	   * next frame
	   */
	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
					   to_next, n_left_to_next,
					   bi0, next0);

	}
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }
  u32 pit_int_count = hicn_pit_get_int_count (rt->pitcs);
  u32 pit_cs_count = hicn_pit_get_cs_count (rt->pitcs);
  u32 pcs_ntw_count = hicn_pcs_get_ntw_count (rt->pitcs);


  vlib_node_increment_counter (vm, hicn_interest_pcslookup_node.index,
			       HICNFWD_ERROR_PROCESSED, stats.pkts_processed);

  vlib_node_increment_counter (vm, hicn_interest_pcslookup_node.index,
			       HICNFWD_ERROR_INTERESTS,
			       stats.pkts_interest_count);

  update_node_counter (vm, hicn_interest_pcslookup_node.index,
		       HICNFWD_ERROR_INT_COUNT, pit_int_count);

  update_node_counter (vm, hicn_interest_pcslookup_node.index,
		       HICNFWD_ERROR_CS_COUNT, pit_cs_count);

  update_node_counter (vm, hicn_interest_pcslookup_node.index,
		       HICNFWD_ERROR_CS_NTW_COUNT, pcs_ntw_count);

  return (frame->n_vectors);
}

/* packet trace format function */
static u8 *
hicn_interest_pcslookup_format_trace (u8 * s, va_list * args)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  hicn_interest_pcslookup_trace_t *t =
    va_arg (*args, hicn_interest_pcslookup_trace_t *);

  s = format (s, "INTEREST_PCSLOOKUP: pkt: %d, sw_if_index %d, next index %d",
	      (int) t->pkt_type, t->sw_if_index, t->next_index);
  return (s);
}


/*
 * Node registration for the interest forwarder node
 */
/* *INDENT-OFF* */
VLIB_REGISTER_NODE(hicn_interest_pcslookup_node) =
{
  .function = hicn_interest_pcslookup_node_fn,
  .name = "hicn-interest-pcslookup",
  .vector_size = sizeof(u32),
  .runtime_data_bytes = sizeof(hicn_interest_pcslookup_runtime_t),
  .format_trace = hicn_interest_pcslookup_format_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN(hicn_interest_pcslookup_error_strings),
  .error_strings = hicn_interest_pcslookup_error_strings,
  .n_next_nodes = HICN_INTEREST_PCSLOOKUP_N_NEXT,
  .next_nodes =
  {
    [HICN_INTEREST_PCSLOOKUP_NEXT_V4_LOOKUP] = "ip4-lookup",
    [HICN_INTEREST_PCSLOOKUP_NEXT_V6_LOOKUP] = "ip6-lookup",
    [HICN_INTEREST_PCSLOOKUP_NEXT_INTEREST_HITPIT] = "hicn-interest-hitpit",
    [HICN_INTEREST_PCSLOOKUP_NEXT_INTEREST_HITCS] = "hicn-interest-hitcs",
    [HICN_INTEREST_PCSLOOKUP_NEXT_ERROR_DROP] = "error-drop",
  },
};
/* *INDENT-ON* */

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