/*
 * Copyright (c) 2015 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/ip.h>
#include <vnet/classify/vnet_classify.h>
#include <vnet/classify/input_acl.h>

input_acl_main_t input_acl_main;

static int
vnet_inacl_ip_feature_enable (vlib_main_t * vnm,
                              input_acl_main_t *am,
                              u32 sw_if_index,
                              input_acl_table_id_t tid,
                              int feature_enable)
{

  if (tid == INPUT_ACL_TABLE_L2)
    {
      l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_ACL,
                                  feature_enable);
    }
  else
    { /* IP[46] */
      ip_lookup_main_t * lm;
      ip_config_main_t * ipcm;
      u32 ftype;
      u32 ci;

      if (tid == INPUT_ACL_TABLE_IP4)
        {
          lm = &ip4_main.lookup_main;
          ftype = ip4_main.ip4_unicast_rx_feature_check_access;
        }
      else
        {
          lm = &ip6_main.lookup_main;
          ftype = ip6_main.ip6_unicast_rx_feature_check_access;
        }

      ipcm = &lm->feature_config_mains[VNET_IP_RX_UNICAST_FEAT];

      ci = ipcm->config_index_by_sw_if_index[sw_if_index];
      ci = ((feature_enable)
            ? vnet_config_add_feature
            : vnet_config_del_feature)
        (vnm, &ipcm->config_main, ci, ftype,
         /* config data */ 0,
         /* # bytes of config data */ 0);

      ipcm->config_index_by_sw_if_index[sw_if_index] = ci;
      am->vnet_config_main[tid] = &ipcm->config_main;
    }

  return 0;
}

int vnet_set_input_acl_intfc (vlib_main_t * vm, u32 sw_if_index,
                              u32 ip4_table_index,
                              u32 ip6_table_index,
                              u32 l2_table_index, u32 is_add)
{
  input_acl_main_t * am = &input_acl_main;
  vnet_classify_main_t * vcm = am->vnet_classify_main;
  u32 acl[INPUT_ACL_N_TABLES] = {ip4_table_index, ip6_table_index,
                                 l2_table_index};
  u32 ti;

  /* Assume that we've validated sw_if_index in the API layer */

  for (ti = 0; ti < INPUT_ACL_N_TABLES; ti++)
    {
      if (acl[ti] == ~0)
        continue;

      if (pool_is_free_index (vcm->tables, acl[ti]))
        return VNET_API_ERROR_NO_SUCH_TABLE;

      vec_validate_init_empty
        (am->classify_table_index_by_sw_if_index[ti], sw_if_index, ~0);

      /* Reject any DEL operation with wrong sw_if_index */
      if (!is_add &&
          (acl[ti] != am->classify_table_index_by_sw_if_index[ti][sw_if_index]))
        {
          clib_warning ("Non-existent intf_idx=%d with table_index=%d for delete",
                        sw_if_index, acl[ti]);
          return VNET_API_ERROR_NO_SUCH_TABLE;
        }

      /* Return ok on ADD operaton if feature is already enabled */
      if (is_add &&
          am->classify_table_index_by_sw_if_index[ti][sw_if_index] != ~0)
          return 0;

      vnet_inacl_ip_feature_enable (vm, am, sw_if_index, ti, is_add);

      if (is_add)
        am->classify_table_index_by_sw_if_index[ti][sw_if_index] = acl[ti];
      else
        am->classify_table_index_by_sw_if_index[ti][sw_if_index] = ~0;
    }

  return 0;
}

static clib_error_t *
set_input_acl_command_fn (vlib_main_t * vm,
                          unformat_input_t * input,
                          vlib_cli_command_t * cmd)
{
  vnet_main_t * vnm = vnet_get_main();
  u32 sw_if_index = ~0;
  u32 ip4_table_index = ~0;
  u32 ip6_table_index = ~0;
  u32 l2_table_index = ~0;
  u32 is_add = 1;
  u32 idx_cnt = 0;
  int rv;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "intfc %U", unformat_vnet_sw_interface,
                    vnm, &sw_if_index))
        ;
      else if (unformat (input, "ip4-table %d", &ip4_table_index))
        idx_cnt++;
      else if (unformat (input, "ip6-table %d", &ip6_table_index))
        idx_cnt++;
      else if (unformat (input, "l2-table %d", &l2_table_index))
        idx_cnt++;
      else if (unformat (input, "del"))
        is_add = 0;
      else
        break;
    }

  if (sw_if_index == ~0)
    return clib_error_return (0, "Interface must be specified.");

  if (!idx_cnt)
    return clib_error_return (0, "Table index should be specified.");

  if (idx_cnt > 1)
    return clib_error_return (0, "Only one table index per API is allowed.");

  rv = vnet_set_input_acl_intfc (vm, sw_if_index, ip4_table_index,
                                 ip6_table_index, l2_table_index, is_add);

  switch (rv)
    {
    case 0:
      break;

    case VNET_API_ERROR_NO_MATCHING_INTERFACE:
      return clib_error_return (0, "No such interface");

    case VNET_API_ERROR_NO_SUCH_ENTRY:
      return clib_error_return (0, "No such classifier table");
    }
  return 0;
}

/*
 * Configure interface to enable/disble input ACL feature:
 * intfc - interface name to be configured as input ACL
 * Ip4-table <index> [del] - enable/disable IP4 input ACL
 * Ip6-table <index> [del] - enable/disable IP6 input ACL
 * l2-table <index> [del] - enable/disable Layer2 input ACL
 *
 * Note: Only one table index per API call is allowed.
 *
 */
VLIB_CLI_COMMAND (set_input_acl_command, static) = {
    .path = "set interface input acl",
    .short_help =
    "set interface input acl intfc <int> [ip4-table <index>]\n"
    "  [ip6-table <index>] [l2-table <index>] [del]",
    .function = set_input_acl_command_fn,
};

clib_error_t *input_acl_init (vlib_main_t *vm)
{
  input_acl_main_t * am = &input_acl_main;
  clib_error_t * error = 0;

  if ((error = vlib_call_init_function (vm, ip_inacl_init)))
    return error;

  am->vlib_main = vm;
  am->vnet_main = vnet_get_main();
  am->vnet_classify_main = &vnet_classify_main;

  return 0;
}

VLIB_INIT_FUNCTION (input_acl_init);

uword unformat_acl_type (unformat_input_t * input, va_list * args)
{
  u32 * acl_type = va_arg (*args, u32 *);
  u32 tid = INPUT_ACL_N_TABLES;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT) {
    if (unformat (input, "ip4"))
      tid = INPUT_ACL_TABLE_IP4;
    else if (unformat (input, "ip6"))
      tid = INPUT_ACL_TABLE_IP6;
    else if (unformat (input, "l2"))
      tid = INPUT_ACL_TABLE_L2;
    else
      break;
  }

  *acl_type = tid;
  return 1;
}

u8 * format_vnet_inacl_info (u8 * s, va_list * va)
{
  input_acl_main_t * am = va_arg (*va, input_acl_main_t *);
  int sw_if_idx = va_arg (*va, int);
  u32 tid = va_arg (*va, u32);

  if (tid == ~0)
    {
      s = format (s, "%10s%20s\t\t%s", "Intfc idx", "Classify table",
                  "Interface name");
      return s;
    }

  s = format (s, "%10d%20d\t\t%U", sw_if_idx, tid,
              format_vnet_sw_if_index_name, am->vnet_main, sw_if_idx);

  return s;
}

static clib_error_t *
show_inacl_command_fn (vlib_main_t * vm,
                       unformat_input_t * input,
                       vlib_cli_command_t * cmd)
{
  input_acl_main_t * am = &input_acl_main;
  u32 type = INPUT_ACL_N_TABLES;
  int i;
  u32 * vec_tbl;

  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat (input, "type %U", unformat_acl_type, &type))
        ;
      else
        break;
    }

  if (type == INPUT_ACL_N_TABLES)
    return clib_error_return (0, "Invalid input ACL table type.");

  vec_tbl = am->classify_table_index_by_sw_if_index[type];

  if (vec_len(vec_tbl))
    vlib_cli_output (vm, "%U", format_vnet_inacl_info, am, ~0 /* hdr */, ~0);
  else
    vlib_cli_output (vm, "No input ACL tables configured");

  for (i = 0; i < vec_len (vec_tbl); i++)
    {
      if (vec_elt(vec_tbl, i) == ~0)
        continue;

      vlib_cli_output (vm, "%U", format_vnet_inacl_info,
                       am, i, vec_elt(vec_tbl, i));
    }

  return 0;
}

VLIB_CLI_COMMAND (show_inacl_command, static) = {
    .path = "show inacl",
    .short_help = "show inacl type [ip4|ip6|l2]",
    .function = show_inacl_command_fn,
};
