/*
 * 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.
 */
/*
 * client.h: dhcp client
 */

#ifndef included_dhcp_client_h
#define included_dhcp_client_h

#include <vnet/ip/ip.h>
#include <vnet/dhcp/dhcp4_packet.h>

#define foreach_dhcp_client_state               \
_(DHCP_DISCOVER)                                \
_(DHCP_REQUEST)                                 \
_(DHCP_BOUND)

typedef enum {
#define _(a) a,
  foreach_dhcp_client_state
#undef _
} dhcp_client_state_t;

typedef struct {
  dhcp_client_state_t state;

  /* the interface in question */
  u32 sw_if_index;

  /* State machine retry counter */
  u32 retry_count;

  /* Send next pkt at this time */
  f64 next_transmit;
  f64 lease_expires;

  /* DHCP transaction ID, a random number */
  u32 transaction_id;

  /* leased address, other learned info DHCP */
  ip4_address_t leased_address; /* from your_ip_address field */
  ip4_address_t dhcp_server;
  u32 subnet_mask_width;        /* option 1 */
  ip4_address_t router_address; /* option 3 */
  u32 lease_renewal_interval;   /* option 51 */
  u32 lease_lifetime;           /* option 59 */

  /* Requested data (option 55) */
  u8 * option_55_data;

  u8 * l2_rewrite;

  /* hostname and software client identifiers */
  u8 * hostname;
  u8 * client_identifier;       /* software version, e.g. vpe 1.0*/

  /* Information used for event callback */
  u32 client_index;
  u32 pid;
  void * event_callback;
} dhcp_client_t;

typedef struct {
  /* DHCP client pool */
  dhcp_client_t * clients;
  uword * client_by_sw_if_index;
  u32 seed;

  /* convenience */
  vlib_main_t * vlib_main;
  vnet_main_t * vnet_main;
} dhcp_client_main_t;

typedef struct {
  int is_add;
  u32 sw_if_index;

  /* vectors, consumed by dhcp client code */
  u8 * hostname;
  u8 * client_identifier;

  /* Bytes containing requested option numbers */
  u8 * option_55_data;

  /* Information used for event callback */
  u32 client_index;
  u32 pid;
  void * event_callback;
} dhcp_client_add_del_args_t;

extern dhcp_client_main_t dhcp_client_main;

#define EVENT_DHCP_CLIENT_WAKEUP	1

int dhcp_client_for_us (u32 bi0, 
                          vlib_buffer_t * b0,
                          ip4_header_t * ip0, 
                          udp_header_t * u0,
                          dhcp_header_t * dh0);

int dhcp_client_config (vlib_main_t * vm,
                        u32 sw_if_index,
                        u8 * hostname,
                        u8 * client_id,
                        u32 is_add,
                        u32 client_index,
                        void *event_callback,
                        u32 pid);

#endif /* included_dhcp_client_h */