/*
 * tunnel_dp.h: data-plane functions tunnels.
 *
 * Copyright (c) 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.
 */

#ifndef __TUNNEL_DP_H__
#define __TUNNEL_DP_H__

#include <vnet/tunnel/tunnel.h>
#include <vnet/mpls/mpls_lookup.h>

static_always_inline void
tunnel_encap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
			const ip4_header_t * inner, ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
    ip4_header_set_dscp (outer, ip4_header_get_dscp (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
    ip4_header_set_ecn (outer, ip4_header_get_ecn (inner));
  if (PREDICT_FALSE ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
		     ip4_header_get_df (inner)))
    ip4_header_set_df (outer);
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
    ip4_header_set_ttl (outer, ip4_header_get_ttl (inner));
}

static_always_inline void
tunnel_encap_fixup_4o4_w_chksum (tunnel_encap_decap_flags_t flags,
				 const ip4_header_t * inner,
				 ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
			      TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)))
    {
      ip_csum_t sum = outer->checksum;
      u8 tos = outer->tos;

      if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
	ip4_header_set_dscp (outer, ip4_header_get_dscp (inner));
      if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
	ip4_header_set_ecn (outer, ip4_header_get_ecn (inner));

      sum =
	ip_csum_update (outer->checksum, tos, outer->tos, ip4_header_t, tos);
      outer->checksum = ip_csum_fold (sum);
    }
  if (PREDICT_FALSE ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
		     ip4_header_get_df (inner)))
    {
      ip_csum_t sum = outer->checksum;
      u16 tos = outer->flags_and_fragment_offset;

      ip4_header_set_df (outer);

      sum =
	ip_csum_update (outer->checksum, tos, outer->tos, ip4_header_t,
			flags_and_fragment_offset);
      outer->checksum = ip_csum_fold (sum);
    }
}

static_always_inline void
tunnel_encap_fixup_mplso4_w_chksum (tunnel_encap_decap_flags_t flags,
				    const mpls_unicast_header_t *inner,
				    ip4_header_t *outer)
{
  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
    {
      ip_csum_t sum = outer->checksum;
      u8 tos = outer->tos;

      if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
	ip4_header_set_dscp (outer,
			     vnet_mpls_uc_get_exp (inner->label_exp_s_ttl));

      sum =
	ip_csum_update (outer->checksum, tos, outer->tos, ip4_header_t, tos);
      outer->checksum = ip_csum_fold (sum);
    }
}

static_always_inline void
tunnel_encap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
			const ip6_header_t * inner, ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
    ip4_header_set_dscp (outer, ip6_dscp_network_order (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
    ip4_header_set_ecn (outer, ip6_ecn_network_order ((inner)));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
    ip4_header_set_ttl (outer, ip6_hop_limit_network_order (inner));
}

static_always_inline void
tunnel_encap_fixup_6o4_w_chksum (tunnel_encap_decap_flags_t flags,
				 const ip6_header_t * inner,
				 ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
			      TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)))
    {
      ip_csum_t sum = outer->checksum;
      u8 tos = outer->tos;

      if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
	ip4_header_set_dscp (outer, ip6_dscp_network_order (inner));
      if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
	ip4_header_set_ecn (outer, ip6_ecn_network_order ((inner)));

      sum =
	ip_csum_update (outer->checksum, tos, outer->tos, ip4_header_t, tos);
      outer->checksum = ip_csum_fold (sum);
    }
}

static_always_inline void
tunnel_encap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
			const ip6_header_t * inner, ip6_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
    ip6_set_dscp_network_order (outer, ip6_dscp_network_order (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
    ip6_set_ecn_network_order (outer, ip6_ecn_network_order (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
    ip6_set_flow_label_network_order (outer,
				      ip6_flow_label_network_order (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
    ip6_set_hop_limit_network_order (outer,
				     ip6_hop_limit_network_order (inner));
}

static_always_inline void
tunnel_encap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
			const vlib_buffer_t *b, const ip4_header_t *inner,
			ip6_header_t *outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
    ip6_set_dscp_network_order (outer, ip4_header_get_dscp (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
    ip6_set_ecn_network_order (outer, ip4_header_get_ecn (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
    ip6_set_hop_limit_network_order (outer, ip4_header_get_ttl (inner));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
    ip6_set_flow_label_network_order (
      outer, (0 != vnet_buffer (b)->ip.flow_hash ?
		vnet_buffer (b)->ip.flow_hash :
		ip4_compute_flow_hash (inner, IP_FLOW_HASH_DEFAULT)));
}

static_always_inline void
tunnel_encap_fixup_mplso6 (tunnel_encap_decap_flags_t flags,
			   const vlib_buffer_t *b,
			   const mpls_unicast_header_t *inner,
			   ip6_header_t *outer)
{
  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
    ip6_set_dscp_network_order (outer,
				vnet_mpls_uc_get_exp (inner->label_exp_s_ttl));
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
    ip6_set_flow_label_network_order (
      outer, (0 != vnet_buffer (b)->ip.flow_hash ?
		vnet_buffer (b)->ip.flow_hash :
		mpls_compute_flow_hash (inner, IP_FLOW_HASH_DEFAULT)));
}

static_always_inline void
tunnel_encap_fixup_mplso4 (tunnel_encap_decap_flags_t flags,
			   const mpls_unicast_header_t *inner,
			   ip4_header_t *outer)
{
  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
    ip4_header_set_dscp (outer, vnet_mpls_uc_get_exp (inner->label_exp_s_ttl));
}

static_always_inline void
tunnel_decap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
			ip4_header_t * inner, const ip6_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
    ip4_header_set_ecn_w_chksum (inner, ip6_ecn_network_order (outer));
}

static_always_inline void
tunnel_decap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
			ip6_header_t * inner, const ip6_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
    ip6_set_ecn_network_order (inner, ip6_ecn_network_order (outer));
}

static_always_inline void
tunnel_decap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
			ip6_header_t * inner, const ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
    ip6_set_ecn_network_order (inner, ip4_header_get_ecn (outer));
}

static_always_inline void
tunnel_decap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
			ip4_header_t * inner, const ip4_header_t * outer)
{
  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
    ip4_header_set_ecn_w_chksum (inner, ip4_header_get_ecn (outer));
}

static_always_inline void
tunnel_decap_fixup_mplso6 (tunnel_encap_decap_flags_t flags,
			   mpls_unicast_header_t *inner,
			   const ip6_header_t *outer)
{
}

static_always_inline void
tunnel_decap_fixup_mplso4 (tunnel_encap_decap_flags_t flags,
			   mpls_unicast_header_t *inner,
			   const ip4_header_t *outer)
{
}

#endif

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