/*
  *  OpenVPN -- An application to securely tunnel IP networks
  *             over a single TCP/UDP port, with support for SSL/TLS-based
  *             session authentication and key exchange,
  *             packet encryption, packet authentication, and
  *             packet compression.
  *

  *  Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net>

  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2
  *  as published by the Free Software Foundation.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *

  *  You should have received a copy of the GNU General Public License along
  *  with this program; if not, write to the Free Software Foundation, Inc.,
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

  */
 
 #ifndef DHCP_H
 #define DHCP_H
 
 #include "common.h"
 #include "buffer.h"
 #include "proto.h"
 
 #pragma pack(1)
 
 /* DHCP Option types */
 #define DHCP_PAD          0
 #define DHCP_ROUTER       3
 #define DHCP_MSG_TYPE    53  /* message type (u8) */
 #define DHCP_END        255
 
 /* DHCP Messages types */
 #define DHCPDISCOVER 1
 #define DHCPOFFER    2
 #define DHCPREQUEST  3
 #define DHCPDECLINE  4
 #define DHCPACK      5
 #define DHCPNAK      6
 #define DHCPRELEASE  7
 #define DHCPINFORM   8
 
 /* DHCP UDP port numbers */
 #define BOOTPS_PORT 67
 #define BOOTPC_PORT 68
 
 struct dhcp {

 #define BOOTREQUEST 1
 #define BOOTREPLY   2
     uint8_t op;        /* message op */

     uint8_t htype;     /* hardware address type (e.g. '1' = 10Mb Ethernet) */
     uint8_t hlen;      /* hardware address length (e.g. '6' for 10Mb Ethernet) */
     uint8_t hops;      /* client sets to 0, may be used by relay agents */
     uint32_t xid;      /* transaction ID, chosen by client */
     uint16_t secs;     /* seconds since request process began, set by client */
     uint16_t flags;
     uint32_t ciaddr;   /* client IP address, client sets if known */
     uint32_t yiaddr;   /* 'your' IP address -- server's response to client */
     uint32_t siaddr;   /* server IP address */
     uint32_t giaddr;   /* relay agent IP address */
     uint8_t chaddr[16]; /* client hardware address */
     uint8_t sname[64]; /* optional server host name */
     uint8_t file[128]; /* boot file name */
     uint32_t magic;    /* must be 0x63825363 (network order) */

 };
 
 struct dhcp_full {

     struct openvpn_iphdr ip;
     struct openvpn_udphdr udp;
     struct dhcp dhcp;
 #define DHCP_OPTIONS_BUFFER_SIZE 256
     uint8_t options[DHCP_OPTIONS_BUFFER_SIZE];

 };
 
 #pragma pack()
 

 in_addr_t dhcp_extract_router_msg(struct buffer *ipbuf);

 #endif /* ifndef DHCP_H */