/** @file
Functions implementation related with DHCPv4/v6 for DNS driver.

Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#ifndef _DNS_DHCP_H_
#define _DNS_DHCP_H_

//
// DHCP DNS related
//
#pragma pack(1)

#define IP4_ETHER_PROTO       0x0800

#define DHCP4_OPCODE_REQUEST         1
#define DHCP4_MAGIC                  0x63538263 /// network byte order
#define DHCP4_TAG_EOP                255  /// End Option

#define DHCP4_TAG_TYPE               53
#define DHCP4_MSG_REQUEST            3
#define DHCP4_MSG_INFORM             8

#define DHCP4_TAG_PARA_LIST          55
#define DHCP4_TAG_DNS_SERVER         6


#define DHCP6_TAG_DNS_REQUEST        6
#define DHCP6_TAG_DNS_SERVER         23

//
// The required Dns4 server information.
//
typedef struct {
  UINT32                     *ServerCount;
  EFI_IPv4_ADDRESS           *ServerList;
} DNS4_SERVER_INFOR;

//
// The required Dns6 server information.
//
typedef struct {
  UINT32                     *ServerCount;
  EFI_IPv6_ADDRESS           *ServerList;
} DNS6_SERVER_INFOR;

#pragma pack()

/**
  Parse the ACK to get required information

  @param  Dhcp4            The DHCP4 protocol.
  @param  Packet           Packet waiting for parse.
  @param  DnsServerInfor   The required Dns4 server information.

  @retval EFI_SUCCESS           The DNS information is got from the DHCP ACK.
  @retval EFI_NO_MAPPING        DHCP failed to acquire address and other information.
  @retval EFI_DEVICE_ERROR      Other errors as indicated.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory.

**/
EFI_STATUS
ParseDhcp4Ack (
  IN EFI_DHCP4_PROTOCOL         *Dhcp4,
  IN EFI_DHCP4_PACKET           *Packet,
  IN DNS4_SERVER_INFOR          *DnsServerInfor
  );

/**
  EFI_DHCP6_INFO_CALLBACK is provided by the consumer of the EFI DHCPv6 Protocol 
  instance to intercept events that occurs in the DHCPv6 Information Request
  exchange process.

  @param  This                  Pointer to the EFI_DHCP6_PROTOCOL instance that 
                                is used to configure this  callback function.
  @param  Context               Pointer to the context that is initialized in
                                the EFI_DHCP6_PROTOCOL.InfoRequest().
  @param  Packet                Pointer to Reply packet that has been received.
                                The EFI DHCPv6 Protocol instance is responsible
                                for freeing the buffer.

  @retval EFI_SUCCESS           The DNS information is got from the DHCP ACK.
  @retval EFI_DEVICE_ERROR      Other errors as indicated.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory.
**/
EFI_STATUS
EFIAPI
ParseDhcp6Ack (
  IN EFI_DHCP6_PROTOCOL          *This,
  IN VOID                        *Context,
  IN EFI_DHCP6_PACKET            *Packet
  );

/**
  Parse the DHCP ACK to get Dns4 server information.

  @param  Instance         The DNS instance.
  @param  DnsServerCount   Retrieved Dns4 server Ip count.
  @param  DnsServerList    Retrieved Dns4 server Ip list.

  @retval EFI_SUCCESS           The Dns4 information is got from the DHCP ACK.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory.
  @retval EFI_NO_MEDIA          There was a media error.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
GetDns4ServerFromDhcp4 (
  IN  DNS_INSTANCE               *Instance,
  OUT UINT32                     *DnsServerCount,
  OUT EFI_IPv4_ADDRESS           **DnsServerList
  );

/**
  Parse the DHCP ACK to get Dns6 server information.

  @param  Image            The handle of the driver image.
  @param  Controller       The handle of the controller.
  @param  DnsServerCount   Retrieved Dns6 server Ip count.
  @param  DnsServerList    Retrieved Dns6 server Ip list.

  @retval EFI_SUCCESS           The Dns6 information is got from the DHCP ACK.
  @retval EFI_OUT_OF_RESOURCES  Failed to allocate memory.
  @retval EFI_NO_MEDIA          There was a media error.
  @retval Others                Other errors as indicated.

**/
EFI_STATUS
GetDns6ServerFromDhcp6 (
  IN  EFI_HANDLE                 Image,
  IN  EFI_HANDLE                 Controller,
  OUT UINT32                     *DnsServerCount,
  OUT EFI_IPv6_ADDRESS           **DnsServerList
  );
  
#endif