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

#define _GNU_SOURCE
#include <stdint.h>
#include <vnet/llc/llc.h>
#include <vnet/snap/snap.h>
#include <vnet/bonding/node.h>

bond_main_t bond_main;

#define foreach_bond_input_error \
  _(NONE, "no error")            \
  _(IF_DOWN, "interface down")   \
  _(NO_SLAVE, "no slave")        \
  _(NO_BOND, "no bond interface")\
  _(PASS_THRU, "pass through")

typedef enum
{
#define _(f,s) BOND_INPUT_ERROR_##f,
  foreach_bond_input_error
#undef _
    BOND_INPUT_N_ERROR,
} bond_input_error_t;

static char *bond_input_error_strings[] = {
#define _(n,s) s,
  foreach_bond_input_error
#undef _
};

static u8 *
format_bond_input_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 *);
  bond_packet_trace_t *t = va_arg (*args, bond_packet_trace_t *);
  vnet_hw_interface_t *hw, *hw1;
  vnet_main_t *vnm = vnet_get_main ();

  hw = vnet_get_sup_hw_interface (vnm, t->sw_if_index);
  hw1 = vnet_get_sup_hw_interface (vnm, t->bond_sw_if_index);
  s = format (s, "src %U, dst %U, %s -> %s",
	      format_ethernet_address, t->ethernet.src_address,
	      format_ethernet_address, t->ethernet.dst_address,
	      hw->name, hw1->name);

  return s;
}

static_always_inline u8
packet_is_cdp (ethernet_header_t * eth)
{
  llc_header_t *llc;
  snap_header_t *snap;

  llc = (llc_header_t *) (eth + 1);
  snap = (snap_header_t *) (llc + 1);

  return ((eth->type == htons (ETHERNET_TYPE_CDP)) ||
	  ((llc->src_sap == 0xAA) && (llc->control == 0x03) &&
	   (snap->protocol == htons (0x2000)) &&
	   (snap->oui[0] == 0) && (snap->oui[1] == 0) &&
	   (snap->oui[2] == 0x0C)));
}

static inline void
bond_sw_if_index_rewrite (vlib_main_t * vm, vlib_node_runtime_t * node,
			  slave_if_t * sif, ethernet_header_t * eth,
			  vlib_buffer_t * b0)
{
  bond_if_t *bif;
  u16 thread_index = vlib_get_thread_index ();
  u16 *ethertype_p, ethertype;
  ethernet_vlan_header_t *vlan;

  if (PREDICT_TRUE (sif != 0))
    {
      bif = bond_get_master_by_sw_if_index (sif->group);
      if (PREDICT_TRUE (bif != 0))
	{
	  if (PREDICT_TRUE (vec_len (bif->slaves) >= 1))
	    {
	      if (PREDICT_TRUE (bif->admin_up == 1))
		{
		  if (!ethernet_frame_is_tagged (ntohs (eth->type)))
		    {
		      // Let some layer2 packets pass through.
		      if (PREDICT_TRUE ((eth->type !=
					 htons (ETHERNET_TYPE_SLOW_PROTOCOLS))
					&& !packet_is_cdp (eth)
					&& (eth->type !=
					    htons
					    (ETHERNET_TYPE_802_1_LLDP))))
			{
			  // Change the physical interface to
			  // bond interface
			  vnet_buffer (b0)->sw_if_index[VLIB_RX] =
			    bif->sw_if_index;

			  /* increase rx counters */
			  vlib_increment_simple_counter
			    (vnet_main.interface_main.sw_if_counters +
			     VNET_INTERFACE_COUNTER_RX, thread_index,
			     bif->sw_if_index, 1);
			}
		      else
			{
			  vlib_error_count (vm, node->node_index,
					    BOND_INPUT_ERROR_PASS_THRU, 1);
			}
		    }
		  else
		    {
		      vlan = (void *) (eth + 1);
		      ethertype_p = &vlan->type;
		      if (*ethertype_p == ntohs (ETHERNET_TYPE_VLAN))
			{
			  vlan++;
			  ethertype_p = &vlan->type;
			}
		      ethertype = *ethertype_p;
		      if (PREDICT_TRUE ((ethertype !=
					 htons (ETHERNET_TYPE_SLOW_PROTOCOLS))
					&& (ethertype !=
					    htons (ETHERNET_TYPE_CDP))
					&& (ethertype !=
					    htons
					    (ETHERNET_TYPE_802_1_LLDP))))
			{
			  // Change the physical interface to
			  // bond interface
			  vnet_buffer (b0)->sw_if_index[VLIB_RX] =
			    bif->sw_if_index;

			  /* increase rx counters */
			  vlib_increment_simple_counter
			    (vnet_main.interface_main.sw_if_counters +
			     VNET_INTERFACE_COUNTER_RX, thread_index,
			     bif->sw_if_index, 1);
			}
		      else
			{
			  vlib_error_count (vm, node->node_index,
					    BOND_INPUT_ERROR_PASS_THRU, 1);
			}
		    }
		}
	      else
		{
		  vlib_error_count (vm, node->node_index,
				    BOND_INPUT_ERROR_IF_DOWN, 1);
		}
	    }
	  else
	    {
	      vlib_error_count (vm, node->node_index,
				BOND_INPUT_ERROR_NO_SLAVE, 1);
	    }
	}
      else
	{
	  vlib_error_count (vm, node->node_index,
			    BOND_INPUT_ERROR_NO_BOND, 1);
	}
    }
  else
    {
      vlib_error_count (vm, node->node_index, BOND_INPUT_ERROR_NO_SLAVE, 1);
    }

}

static uword
bond_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
	       vlib_frame_t * frame)
{
  u32 bi0, bi1, bi2, bi3;
  vlib_buffer_t *b0, *b1, *b2, *b3;
  u32 next_index;
  u32 *from, *to_next, n_left_from, n_left_to_next;
  ethernet_header_t *eth, *eth1, *eth2, *eth3;
  u32 next0, next1, next2, next3;
  bond_packet_trace_t *t0;
  uword n_trace = vlib_get_trace_count (vm, node);
  u32 sw_if_index, sw_if_index1, sw_if_index2, sw_if_index3;
  slave_if_t *sif, *sif1, *sif2, *sif3;
  u16 thread_index = vlib_get_thread_index ();

  /* Vector of buffer / pkt indices we're supposed to process */
  from = vlib_frame_vector_args (frame);

  /* Number of buffers / pkts */
  n_left_from = frame->n_vectors;

  /* Speculatively send the first buffer to the last disposition we used */
  next_index = node->cached_next_index;

  while (n_left_from > 0)
    {
      /* set up to enqueue to our disposition with index = next_index */
      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);

      while (n_left_from >= 12 && n_left_to_next >= 4)
	{
	  // Prefetch next iteration
	  {
	    vlib_buffer_t *b4, *b5, *b6, *b7;

	    b4 = vlib_get_buffer (vm, from[4]);
	    b5 = vlib_get_buffer (vm, from[5]);
	    b6 = vlib_get_buffer (vm, from[6]);
	    b7 = vlib_get_buffer (vm, from[7]);

	    vlib_prefetch_buffer_header (b4, STORE);
	    vlib_prefetch_buffer_header (b5, STORE);
	    vlib_prefetch_buffer_header (b6, STORE);
	    vlib_prefetch_buffer_header (b7, STORE);

	    CLIB_PREFETCH (b4->data, CLIB_CACHE_LINE_BYTES, LOAD);
	    CLIB_PREFETCH (b5->data, CLIB_CACHE_LINE_BYTES, LOAD);
	    CLIB_PREFETCH (b6->data, CLIB_CACHE_LINE_BYTES, LOAD);
	    CLIB_PREFETCH (b7->data, CLIB_CACHE_LINE_BYTES, LOAD);
	  }

	  next0 = 0;
	  next1 = 0;
	  next2 = 0;
	  next3 = 0;

	  bi0 = from[0];
	  bi1 = from[1];
	  bi2 = from[2];
	  bi3 = from[3];

	  to_next[0] = bi0;
	  to_next[1] = bi1;
	  to_next[2] = bi2;
	  to_next[3] = bi3;

	  from += 4;
	  to_next += 4;
	  n_left_from -= 4;
	  n_left_to_next -= 4;

	  b0 = vlib_get_buffer (vm, bi0);
	  b1 = vlib_get_buffer (vm, bi1);
	  b2 = vlib_get_buffer (vm, bi2);
	  b3 = vlib_get_buffer (vm, bi3);

	  vnet_feature_next (vnet_buffer (b0)->sw_if_index[VLIB_RX], &next0,
			     b0);
	  vnet_feature_next (vnet_buffer (b1)->sw_if_index[VLIB_RX], &next1,
			     b1);
	  vnet_feature_next (vnet_buffer (b2)->sw_if_index[VLIB_RX], &next2,
			     b2);
	  vnet_feature_next (vnet_buffer (b3)->sw_if_index[VLIB_RX], &next3,
			     b3);

	  eth = (ethernet_header_t *) vlib_buffer_get_current (b0);
	  eth1 = (ethernet_header_t *) vlib_buffer_get_current (b1);
	  eth2 = (ethernet_header_t *) vlib_buffer_get_current (b2);
	  eth3 = (ethernet_header_t *) vlib_buffer_get_current (b3);

	  sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
	  sw_if_index2 = vnet_buffer (b2)->sw_if_index[VLIB_RX];
	  sw_if_index3 = vnet_buffer (b3)->sw_if_index[VLIB_RX];

	  // sw_if_index points to the physical interface
	  sif = bond_get_slave_by_sw_if_index (sw_if_index);
	  sif1 = bond_get_slave_by_sw_if_index (sw_if_index1);
	  sif2 = bond_get_slave_by_sw_if_index (sw_if_index2);
	  sif3 = bond_get_slave_by_sw_if_index (sw_if_index3);

	  bond_sw_if_index_rewrite (vm, node, sif, eth, b0);
	  bond_sw_if_index_rewrite (vm, node, sif1, eth1, b1);
	  bond_sw_if_index_rewrite (vm, node, sif2, eth2, b2);
	  bond_sw_if_index_rewrite (vm, node, sif3, eth3, b3);

	  if (PREDICT_FALSE (n_trace > 0))
	    {
	      vlib_trace_buffer (vm, node, next0, b0, 0 /* follow_chain */ );
	      vlib_set_trace_count (vm, node, --n_trace);
	      t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
	      t0->ethernet = *eth;
	      t0->sw_if_index = sw_if_index;
	      t0->bond_sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];

	      if (PREDICT_TRUE (n_trace > 0))
		{
		  vlib_trace_buffer (vm, node, next1, b1,
				     0 /* follow_chain */ );
		  vlib_set_trace_count (vm, node, --n_trace);
		  t0 = vlib_add_trace (vm, node, b1, sizeof (*t0));
		  t0->ethernet = *eth1;
		  t0->sw_if_index = sw_if_index1;
		  t0->bond_sw_if_index =
		    vnet_buffer (b1)->sw_if_index[VLIB_RX];

		  if (PREDICT_TRUE (n_trace > 0))
		    {
		      vlib_trace_buffer (vm, node, next1, b2,
					 0 /* follow_chain */ );
		      vlib_set_trace_count (vm, node, --n_trace);
		      t0 = vlib_add_trace (vm, node, b2, sizeof (*t0));
		      t0->ethernet = *eth2;
		      t0->sw_if_index = sw_if_index2;
		      t0->bond_sw_if_index =
			vnet_buffer (b2)->sw_if_index[VLIB_RX];

		      if (PREDICT_TRUE (n_trace > 0))
			{
			  vlib_trace_buffer (vm, node, next1, b2,
					     0 /* follow_chain */ );
			  vlib_set_trace_count (vm, node, --n_trace);
			  t0 = vlib_add_trace (vm, node, b3, sizeof (*t0));
			  t0->ethernet = *eth3;
			  t0->sw_if_index = sw_if_index3;
			  t0->bond_sw_if_index =
			    vnet_buffer (b3)->sw_if_index[VLIB_RX];
			}
		    }
		}
	    }

	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);
	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b1);
	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b2);
	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b3);

	  /* verify speculative enqueue, maybe switch current next frame */
	  vlib_validate_buffer_enqueue_x4 (vm, node, next_index,
					   to_next, n_left_to_next,
					   bi0, bi1, bi2, bi3, next0, next1,
					   next2, next3);
	}

      while (n_left_from > 0 && n_left_to_next > 0)
	{
	  // Prefetch next iteration
	  if (n_left_from > 1)
	    {
	      vlib_buffer_t *p2;

	      p2 = vlib_get_buffer (vm, from[1]);
	      vlib_prefetch_buffer_header (p2, STORE);
	      CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, LOAD);
	    }

	  next0 = 0;
	  bi0 = from[0];
	  to_next[0] = bi0;
	  from += 1;
	  to_next += 1;
	  n_left_from -= 1;
	  n_left_to_next -= 1;

	  b0 = vlib_get_buffer (vm, bi0);
	  vnet_feature_next (vnet_buffer (b0)->sw_if_index[VLIB_RX], &next0,
			     b0);

	  eth = (ethernet_header_t *) vlib_buffer_get_current (b0);

	  sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
	  // sw_if_index points to the physical interface
	  sif = bond_get_slave_by_sw_if_index (sw_if_index);
	  bond_sw_if_index_rewrite (vm, node, sif, eth, b0);

	  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);

	  /* 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);
    }

  vlib_node_increment_counter (vm, bond_input_node.index,
			       BOND_INPUT_ERROR_NONE, frame->n_vectors);

  vnet_device_increment_rx_packets (thread_index, frame->n_vectors);

  return frame->n_vectors;
}

static clib_error_t *
bond_input_init (vlib_main_t * vm)
{
  return 0;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (bond_input_node) = {
  .function = bond_input_fn,
  .name = "bond-input",
  .vector_size = sizeof (u32),
  .format_buffer = format_ethernet_header_with_length,
  .format_trace = format_bond_input_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = BOND_INPUT_N_ERROR,
  .error_strings = bond_input_error_strings,
  .n_next_nodes = 0,
  .next_nodes =
  {
    [0] = "error-drop"
  }
};

VLIB_INIT_FUNCTION (bond_input_init);

VNET_FEATURE_INIT (bond_input, static) =
{
  .arc_name = "device-input",
  .node_name = "bond-input",
  .runs_before = VNET_FEATURES ("ethernet-input"),
};
VLIB_NODE_FUNCTION_MULTIARCH (bond_input_node, bond_input_fn)
/* *INDENT-ON* */

static clib_error_t *
bond_sw_interface_up_down (vnet_main_t * vnm, u32 sw_if_index, u32 flags)
{
  bond_main_t *bm = &bond_main;
  slave_if_t *sif;
  vlib_main_t *vm = bm->vlib_main;

  sif = bond_get_slave_by_sw_if_index (sw_if_index);
  if (sif)
    {
      sif->port_enabled = flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP;
      if (sif->port_enabled == 0)
	{
	  if (sif->lacp_enabled == 0)
	    {
	      bond_disable_collecting_distributing (vm, sif);
	    }
	}
      else
	{
	  if (sif->lacp_enabled == 0)
	    {
	      bond_enable_collecting_distributing (vm, sif);
	    }
	}
    }

  return 0;
}

VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (bond_sw_interface_up_down);

static clib_error_t *
bond_hw_interface_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
{
  bond_main_t *bm = &bond_main;
  slave_if_t *sif;
  vnet_sw_interface_t *sw;
  vlib_main_t *vm = bm->vlib_main;
  vnet_interface_main_t *im = &vnm->interface_main;

  sw = pool_elt_at_index (im->sw_interfaces, hw_if_index);
  sif = bond_get_slave_by_sw_if_index (sw->sw_if_index);
  if (sif)
    {
      if (!(flags & VNET_HW_INTERFACE_FLAG_LINK_UP))
	{
	  if (sif->lacp_enabled == 0)
	    {
	      bond_disable_collecting_distributing (vm, sif);
	    }
	}
      else
	{
	  if (sif->lacp_enabled == 0)
	    {
	      bond_enable_collecting_distributing (vm, sif);
	    }
	}
    }

  return 0;
}

VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION (bond_hw_interface_up_down);

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