/*
 * l2_vtr.c : layer 2 vlan tag rewrite configuration
 *
 * Copyright (c) 2013 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 <vlib/vlib.h>
#include <vnet/vnet.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/ethernet/packet.h>
#include <vnet/l2/l2_input.h>
#include <vnet/l2/l2_output.h>
#include <vnet/l2/feat_bitmap.h>
#include <vnet/l2/l2_vtr.h>
#include <vnet/l2/l2_input_vtr.h>
#include <vnet/l2/l2_output.h>

#include <vppinfra/error.h>
#include <vlib/cli.h>


// Just a placeholder. Also insures file is not eliminated by linker.
clib_error_t *l2_vtr_init (vlib_main_t *vm)
{
  return 0;
}

VLIB_INIT_FUNCTION(l2_vtr_init);


// Configure vtag tag rewrite on the given interface.
// Return 1 if there is an error, 0 if ok
u32 l2vtr_configure (vlib_main_t * vlib_main,
                     vnet_main_t * vnet_main,
                     u32           sw_if_index,
                     u32           vtr_op,
                     u32           push_dot1q, // ethertype of first pushed tag is dot1q/dot1ad
                     u32           vtr_tag1,   // first pushed tag
                     u32           vtr_tag2)   // second pushed tag
{
  vnet_hw_interface_t * hi;
  vnet_sw_interface_t * si;
  u32 hw_no_tags;
  u32 error = 0;
  vtr_config_t * in_config;
  vtr_config_t * out_config;
  u32 enable;
  u32 push_inner_et;
  u32 push_outer_et;
  u32 cfg_tags;

  hi = vnet_get_sup_hw_interface (vnet_main, sw_if_index);
  if (!hi || (hi->hw_class_index != ethernet_hw_interface_class.index)) {
    error = VNET_API_ERROR_INVALID_INTERFACE;  // non-ethernet interface
    goto done;
  }

  // Init the config for this interface
  vec_validate (l2output_main.configs, sw_if_index);
  in_config = &(vec_elt_at_index(l2output_main.configs, sw_if_index)->input_vtr);
  out_config = &(vec_elt_at_index(l2output_main.configs, sw_if_index)->output_vtr);
  in_config->raw_tags = 0;
  out_config->raw_tags = 0;

  // Get the configured tags for the interface
  si = vnet_get_sw_interface (vnet_main, sw_if_index);
  hw_no_tags = (si->type == VNET_SW_INTERFACE_TYPE_HARDWARE);

  // Construct the input tag-rewrite config

  push_outer_et = clib_net_to_host_u16 (push_dot1q ? ETHERNET_TYPE_VLAN : ETHERNET_TYPE_DOT1AD);
  push_inner_et = clib_net_to_host_u16 (ETHERNET_TYPE_VLAN);
  vtr_tag1 = clib_net_to_host_u16 (vtr_tag1);
  vtr_tag2 = clib_net_to_host_u16 (vtr_tag2);

  // Determine number of vlan tags with explictly configured values
  cfg_tags = 0;
  if (hw_no_tags || si->sub.eth.flags.no_tags) {
    cfg_tags = 0;
  } else if (si->sub.eth.flags.one_tag) {
    cfg_tags = 1;
    if (si->sub.eth.flags.outer_vlan_id_any) {
      cfg_tags = 0;
    }
  } else if (si->sub.eth.flags.two_tags) {
    cfg_tags = 2;
    if (si->sub.eth.flags.inner_vlan_id_any) {
      cfg_tags = 1;
    }
    if (si->sub.eth.flags.outer_vlan_id_any) {
      cfg_tags = 0;
    }
  } 

  switch (vtr_op) {
  case L2_VTR_DISABLED:
    in_config->push_and_pop_bytes = 0;
    break;

  case L2_VTR_POP_1:
    if (cfg_tags < 1) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need one or two tags
      goto done;
    }
    in_config->pop_bytes = 4;
    in_config->push_bytes = 0;
    break;

  case L2_VTR_POP_2:
    if (cfg_tags < 2) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need two tags
      goto done;
    }
    in_config->pop_bytes = 8;
    in_config->push_bytes = 0;

    out_config->push_bytes = in_config->pop_bytes;
    out_config->pop_bytes = in_config->push_bytes;
    break;

  case L2_VTR_PUSH_1:
    in_config->pop_bytes = 0;
    in_config->push_bytes = 4;
    in_config->tags[1].priority_cfi_and_id = vtr_tag1;
    in_config->tags[1].type = push_outer_et;
    break;

  case L2_VTR_PUSH_2:
    in_config->pop_bytes = 0;
    in_config->push_bytes = 8;
    in_config->tags[0].priority_cfi_and_id = vtr_tag1;
    in_config->tags[0].type = push_outer_et;
    in_config->tags[1].priority_cfi_and_id = vtr_tag2;
    in_config->tags[1].type = push_inner_et;
    break;

  case L2_VTR_TRANSLATE_1_1:
    if (cfg_tags < 1) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need one or two tags
      goto done;
    }
    in_config->pop_bytes = 4;
    in_config->push_bytes = 4;
    in_config->tags[1].priority_cfi_and_id = vtr_tag1;
    in_config->tags[1].type = push_outer_et;
    break;

  case L2_VTR_TRANSLATE_1_2:
    if (cfg_tags < 1) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need one or two tags
      goto done;
    }
    in_config->pop_bytes = 4;
    in_config->push_bytes = 8;
    in_config->tags[0].priority_cfi_and_id = vtr_tag1;
    in_config->tags[0].type = push_outer_et;
    in_config->tags[1].priority_cfi_and_id = vtr_tag2;
    in_config->tags[1].type = push_inner_et;
    break;

  case L2_VTR_TRANSLATE_2_1:
    if (cfg_tags < 2) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need two tags
      goto done;
    }
    in_config->pop_bytes = 8;
    in_config->push_bytes = 4;
    in_config->tags[1].priority_cfi_and_id = vtr_tag1;
    in_config->tags[1].type = push_outer_et;
    break;

  case L2_VTR_TRANSLATE_2_2:
    if (cfg_tags < 2) {
      error = VNET_API_ERROR_INVALID_VLAN_TAG_COUNT; // Need two tags
      goto done;
    }
    in_config->pop_bytes = 8;
    in_config->push_bytes = 8;
    in_config->tags[0].priority_cfi_and_id = vtr_tag1;
    in_config->tags[0].type = push_outer_et;
    in_config->tags[1].priority_cfi_and_id = vtr_tag2;
    in_config->tags[1].type = push_inner_et;
    break;
  }

  // Construct the output tag-rewrite config

  // The push/pop values are always reversed
  out_config->push_bytes = in_config->pop_bytes;
  out_config->pop_bytes = in_config->push_bytes;

  // Any pushed tags are derived from the subinterface config
  push_outer_et = clib_net_to_host_u16 (si->sub.eth.flags.dot1ad ? ETHERNET_TYPE_DOT1AD : ETHERNET_TYPE_VLAN);
  push_inner_et = clib_net_to_host_u16 (ETHERNET_TYPE_VLAN);
  vtr_tag1 = clib_net_to_host_u16 (si->sub.eth.outer_vlan_id);
  vtr_tag2 = clib_net_to_host_u16 (si->sub.eth.inner_vlan_id);

  if (out_config->push_bytes == 4) {
    out_config->tags[1].priority_cfi_and_id = vtr_tag1;
    out_config->tags[1].type = push_outer_et;
  } else if (out_config->push_bytes == 8) {
    out_config->tags[0].priority_cfi_and_id = vtr_tag1;
    out_config->tags[0].type = push_outer_et;
    out_config->tags[1].priority_cfi_and_id = vtr_tag2;
    out_config->tags[1].type = push_inner_et;
  }
  
  // set the interface enable flags
  enable = (vtr_op != L2_VTR_DISABLED);
  l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_VTR, enable);
  // output vtr enable is checked explicitly in l2_output

 done:
  return error;
}

// Get vtag tag rewrite on the given interface.
// Return 1 if there is an error, 0 if ok
u32 l2vtr_get (vlib_main_t * vlib_main,
               vnet_main_t * vnet_main,
               u32           sw_if_index,
               u32           *vtr_op,
               u32           *push_dot1q, // ethertype of first pushed tag is dot1q/dot1ad
               u32           *vtr_tag1,   // first pushed tag
               u32           *vtr_tag2)   // second pushed tag
{
  vnet_hw_interface_t * hi;
  u32 error = 0;
  vtr_config_t * in_config;

  if (!vtr_op || !push_dot1q || !vtr_tag1 || !vtr_tag2) {
    clib_warning ("invalid arguments");
    error = VNET_API_ERROR_INVALID_ARGUMENT;
    goto done;
  }

  *vtr_op = L2_VTR_DISABLED;
  *vtr_tag1 = 0;
  *vtr_tag2 = 0;
  *push_dot1q = 0;

  hi = vnet_get_sup_hw_interface (vnet_main, sw_if_index);
  if (!hi || (hi->hw_class_index != ethernet_hw_interface_class.index)) {
    // non-ethernet interface
    goto done;
  }

  if (sw_if_index >= vec_len(l2output_main.configs)) {
    // no specific config (return disabled)
    goto done;
  }

  // Get the config for this interface
  in_config = &(vec_elt_at_index(l2output_main.configs, sw_if_index)->input_vtr);

  // DISABLED
  if (in_config->push_and_pop_bytes == 0) {
    goto done;
  }

  // find out vtr_op
  switch (in_config->pop_bytes) {
    case 0:
      switch (in_config->push_bytes) {
        case 0:
          // DISABLED
          goto done;
        case 4:
          *vtr_op = L2_VTR_PUSH_1;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[1].type));
          break;
        case 8:
          *vtr_op = L2_VTR_PUSH_2;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[0].priority_cfi_and_id);
          *vtr_tag2 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[0].type));
          break;
        default:
          clib_warning ("invalid push_bytes count: %d", in_config->push_bytes);
          error = VNET_API_ERROR_UNEXPECTED_INTF_STATE;
          goto done;
      }
      break;

    case 4:
      switch (in_config->push_bytes) {
        case 0:
          *vtr_op = L2_VTR_POP_1;
          break;
        case 4:
          *vtr_op = L2_VTR_TRANSLATE_1_1;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[1].type));
          break;
        case 8:
          *vtr_op = L2_VTR_TRANSLATE_1_2;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[0].priority_cfi_and_id);
          *vtr_tag2 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[0].type));
          break;
        default:
          clib_warning ("invalid push_bytes count: %d", in_config->push_bytes);
          error = VNET_API_ERROR_UNEXPECTED_INTF_STATE;
          goto done;
      }
      break;

    case 8:
      switch (in_config->push_bytes) {
        case 0:
          *vtr_op = L2_VTR_POP_2;
          break;
        case 4:
          *vtr_op = L2_VTR_TRANSLATE_2_1;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[1].type));
          break;
        case 8:
          *vtr_op = L2_VTR_TRANSLATE_2_2;
          *vtr_tag1 = clib_host_to_net_u16 (in_config->tags[0].priority_cfi_and_id);
          *vtr_tag2 = clib_host_to_net_u16 (in_config->tags[1].priority_cfi_and_id);
          *push_dot1q = (ETHERNET_TYPE_VLAN == clib_host_to_net_u16 (in_config->tags[0].type));
          break;
        default:
          clib_warning ("invalid push_bytes count: %d", in_config->push_bytes);
          error = VNET_API_ERROR_UNEXPECTED_INTF_STATE;
          goto done;
      }
      break;

    default:
      clib_warning ("invalid pop_bytes count: %d", in_config->pop_bytes);
      error = VNET_API_ERROR_UNEXPECTED_INTF_STATE;
      goto done;
  }

 done:
  return error;
}

// set subinterface vtr enable/disable
// The CLI format is:
//    set interface l2 tag-rewrite <interface> [disable | pop 1 | pop 2 | push {dot1q|dot1ad} <tag> [<tag>]]
// "push" can also be replaced by "translate-{1|2}-{1|2}"
static clib_error_t *
int_l2_vtr (vlib_main_t * vm,
            unformat_input_t * input,
            vlib_cli_command_t * cmd)
{
  vnet_main_t * vnm = vnet_get_main();
  clib_error_t * error = 0;
  u32 sw_if_index;
  u32 vtr_op;
  u32 push_dot1q = 0;
  u32 tag1 = 0, tag2 = 0;

  if (! unformat_user (input, unformat_vnet_sw_interface, vnm, &sw_if_index))
    {
      error = clib_error_return (0, "unknown interface `%U'",
                                 format_unformat_error, input);
      goto done;
    }

  vtr_op = L2_VTR_DISABLED;

  if (unformat (input, "disable")) {
    vtr_op = L2_VTR_DISABLED;
  } else if (unformat (input, "pop 1")) {
    vtr_op = L2_VTR_POP_1;
  } else if (unformat (input, "pop 2")) {
    vtr_op = L2_VTR_POP_2;

  } else if (unformat (input, "push dot1q %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_PUSH_2;
    push_dot1q = 1;
  } else if (unformat (input, "push dot1ad %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_PUSH_2;

  } else if (unformat (input, "push dot1q %d", &tag1)) {
    vtr_op = L2_VTR_PUSH_1;
    push_dot1q = 1;
  } else if (unformat (input, "push dot1ad %d", &tag1)) {
    vtr_op = L2_VTR_PUSH_1;

  } else if (unformat (input, "translate 1-1 dot1q %d", &tag1)) {
    vtr_op = L2_VTR_TRANSLATE_1_1;
    push_dot1q = 1;
  } else if (unformat (input, "translate 1-1 dot1ad %d", &tag1)) {
    vtr_op = L2_VTR_TRANSLATE_1_1;

  } else if (unformat (input, "translate 2-1 dot1q %d", &tag1)) {
    vtr_op = L2_VTR_TRANSLATE_2_1;
    push_dot1q = 1;
  } else if (unformat (input, "translate 2-1 dot1ad %d", &tag1)) {
    vtr_op = L2_VTR_TRANSLATE_2_1;

  } else if (unformat (input, "translate 2-2 dot1q %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_TRANSLATE_2_2;
    push_dot1q = 1;
  } else if (unformat (input, "translate 2-2 dot1ad %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_TRANSLATE_2_2;

  } else if (unformat (input, "translate 1-2 dot1q %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_TRANSLATE_1_2;
    push_dot1q = 1;
  } else if (unformat (input, "translate 1-2 dot1ad %d %d", &tag1, &tag2)) {
    vtr_op = L2_VTR_TRANSLATE_1_2;

  } else {
    error = clib_error_return (0, "expecting [disable | pop 1 | pop 2 | push {dot1q|dot1ah} <tag> [<tag>]\n"
                               " | translate {1|2}-{1|2} {dot1q|dot1ah} <tag> [<tag>]] but got `%U'",
                               format_unformat_error, input);
    goto done;
  }

  if (l2vtr_configure (vm,
                       vnm,
                       sw_if_index,
                       vtr_op,
                       push_dot1q,
                       tag1,
                       tag2)) {
    error = clib_error_return (0, "vlan tag rewrite is not compatible with interface");
    goto done;
  }

 done:
  return error;
}

VLIB_CLI_COMMAND (int_l2_vtr_cli, static) = {
  .path = "set interface l2 tag-rewrite",
  .short_help = "set interface l2 tag-rewrite <interface> [disable | pop {1|2} | push {dot1q|dot1ad} <tag> <tag>]",
  .function = int_l2_vtr,
};