/** @file
  UEFI Dynamic Host Configuration Protocol 6 Definition, which is used to get IPv6
  addresses and other configuration parameters from DHCPv6 servers.

  Copyright (c) 2008 - 2010, 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. 

  @par Revision Reference:          
  This Protocol is introduced in UEFI Specification 2.2

**/

#ifndef __EFI_DHCP6_PROTOCOL_H__
#define __EFI_DHCP6_PROTOCOL_H__

#define EFI_DHCP6_PROTOCOL_GUID \
  { \
    0x87c8bad7, 0x595, 0x4053, {0x82, 0x97, 0xde, 0xde, 0x39, 0x5f, 0x5d, 0x5b } \
  }

#define EFI_DHCP6_SERVICE_BINDING_PROTOCOL_GUID \
  { \
    0x9fb9a8a1, 0x2f4a, 0x43a6, {0x88, 0x9c, 0xd0, 0xf7, 0xb6, 0xc4, 0x7a, 0xd5 } \
  }

typedef struct _EFI_DHCP6_PROTOCOL EFI_DHCP6_PROTOCOL;

typedef enum { 
  ///
  /// The EFI DHCPv6 Protocol instance is configured, and start() needs 
  /// to be called
  ///
  Dhcp6Init                    = 0x0,
  ///
  /// A Solicit packet is sent out to discover DHCPv6 server, and the EFI
  /// DHCPv6 Protocol instance is collecting Advertise packets.
  ///
  Dhcp6Selecting               = 0x1,
  ///
  /// A Request is sent out to the DHCPv6 server, and the EFI DHCPv6 
  /// Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Requesting              = 0x2,
  ///
  /// A Decline packet is sent out to indicate one or more addresses of the
  /// configured IA are in use by another node, and the EFI DHCPv6.
  /// Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Declining               = 0x3,
  ///
  /// A Confirm packet is sent out to confirm the IPv6 addresses of the 
  /// configured IA, and the EFI DHCPv6 Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Confirming              = 0x4,
  ///
  /// A Release packet is sent out to release one or more IPv6 addresses of
  /// the configured IA, and the EFI DHCPv6 Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Releasing               = 0x5,
  ///
  /// The DHCPv6 S.A.R.R process is completed for the configured IA.
  ///
  Dhcp6Bound                   = 0x6,
  ///
  /// A Renew packet is sent out to extend lifetime for the IPv6 addresses of
  /// the configured IA, and the EFI DHCPv6 Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Renewing                = 0x7,
  ///
  /// A Rebind packet is sent out to extend lifetime for the IPv6 addresses of
  /// the configured IA, and the EFI DHCPv6 Protocol instance is waiting for Reply packet.
  ///
  Dhcp6Rebinding               = 0x8
} EFI_DHCP6_STATE;

typedef enum {
  ///     
  /// A Solicit packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6SendSolicit             = 0x0,
  ///     
  /// An Advertise packet is received and will be passed to Dhcp6Callback.
  ///
  Dhcp6RcvdAdvertise           = 0x1,
  ///     
  /// It is time for Dhcp6Callback to determine whether select the default Advertise
  /// packet by RFC 3315 policy, or overwrite it by specific user policy.
  ///
  Dhcp6SelectAdvertise         = 0x2,
  ///     
  /// A Request packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6SendRequest             = 0x3,
  ///     
  /// A Reply packet is received and will be passed to Dhcp6Callback.
  ///
  Dhcp6RcvdReply               = 0x4,
  ///     
  /// A Reconfigure packet is received and will be passed to Dhcp6Callback.
  ///
  Dhcp6RcvdReconfigure         = 0x5,
  ///     
  /// A Decline packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6SendDecline             = 0x6,
  ///     
  /// A Confirm packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6SendConfirm             = 0x7,
  ///     
  /// A Release packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6SendRelease             = 0x8,
  ///     
  /// A Renew packet is about to be sent. The packet is passed to Dhcp6Callback and
  /// can be modified or replaced in Dhcp6Callback. 
  ///
  Dhcp6EnterRenewing           = 0x9,
  ///     
  /// A Rebind packet is about to be sent. The packet is passed to Dhcp6Callback and 
  /// can be modified or replaced in Dhcp6Callback.
  ///
  Dhcp6EnterRebinding          = 0xa
} EFI_DHCP6_EVENT;

///
/// An IA which carries assigned not temporary address.
///
#define EFI_DHCP6_IA_TYPE_NA   3
///
/// An IA which carries assigned temporary address.
///
#define EFI_DHCP6_IA_TYPE_TA   4

#pragma pack(1)
///
/// EFI_DHCP6_PACKET_OPTION
/// defines the format of the DHCPv6 option, See RFC 3315 for more information.
/// This data structure is used to reference option data that is packed in the DHCPv6 packet. 
///
typedef struct {
  ///
  /// The DHCPv6 option code, stored in network order.
  ///
  UINT16                       OpCode;
  ///
  /// Length of the DHCPv6 option data, stored in network order.
  /// From the first byte to the last byte of the Data field.
  ///
  UINT16                       OpLen;
  ///
  /// The data for the DHCPv6 option, stored in network order.
  ///
  UINT8                        Data[1];
} EFI_DHCP6_PACKET_OPTION;

///
/// EFI_DHCP6_HEADER
/// defines the format of the DHCPv6 header. See RFC 3315 for more information. 
///
typedef struct{
  ///
  /// The DHCPv6 transaction ID.
  ///
  UINT32                       MessageType:8;
  ///
  /// The DHCPv6 message type.
  ///
  UINT32                       TransactionId:24;
} EFI_DHCP6_HEADER;

///
/// EFI_DHCP6_PACKET 
/// defines the format of the DHCPv6 packet. See RFC 3315 for more information.
///
typedef struct {
  ///
  /// Size of the EFI_DHCP6_PACKET buffer.
  ///
  UINT32                       Size;
  ///
  /// Length of the EFI_DHCP6_PACKET from the first byte of the Header field to the last
  /// byte of the Option[] field.
  ///
  UINT32                       Length;
  struct{
    ///
    /// The DHCPv6 packet header.
    ///
    EFI_DHCP6_HEADER           Header;
    ///
    /// Start of the DHCPv6 packed option data.
    ///
    UINT8                      Option[1];
  } Dhcp6;
} EFI_DHCP6_PACKET;

#pragma pack()

typedef struct {
  ///
  /// Length of DUID in octects.
  ///
  UINT16                       Length;
  ///
  /// Array of DUID octects.
  ///
  UINT8                        Duid[1];
} EFI_DHCP6_DUID;

typedef struct {
  ///
  /// Initial retransmission timeout.
  ///
  UINT32                       Irt;
  ///
  /// Maximum retransmission count for one packet. If Mrc is zero, there's no upper limit 
  /// for retransmission count.
  ///
  UINT32                       Mrc;
  ///
  /// Maximum retransmission timeout for each retry. It's the upper bound of the number of 
  /// retransmission timeout. If Mrt is zero, there is no upper limit for retransmission 
  /// timeout.
  ///
  UINT32                       Mrt;
  ///
  /// Maximum retransmission duration for one packet. It's the upper bound of the numbers 
  /// the client may retransmit a message. If Mrd is zero, there's no upper limit for 
  /// retransmission duration.
  ///
  UINT32                       Mrd;
} EFI_DHCP6_RETRANSMISSION;

typedef struct {
  ///
  /// The IPv6 address.
  ///
  EFI_IPv6_ADDRESS             IpAddress;
  ///
  /// The preferred lifetime in unit of seconds for the IPv6 address.
  ///
  UINT32                       PreferredLifetime;
  ///
  /// The valid lifetime in unit of seconds for the IPv6 address.
  ///
  UINT32                       ValidLifetime;
} EFI_DHCP6_IA_ADDRESS;

typedef struct {
  UINT16                       Type; ///< Type for an IA.
  UINT32                       IaId; ///< The identifier for an IA.
} EFI_DHCP6_IA_DESCRIPTOR;

typedef struct {
  ///
  /// The descriptor for IA.
  ///
  EFI_DHCP6_IA_DESCRIPTOR      Descriptor;
  ///
  /// The state of the configured IA.
  ///
  EFI_DHCP6_STATE              State;
  ///
  /// Pointer to the cached latest Reply packet. May be NULL if no packet is cached.
  ///
  EFI_DHCP6_PACKET             *ReplyPacket;
  ///
  /// Number of IPv6 addresses of the configured IA.
  ///
  UINT32                       IaAddressCount;
  ///
  /// List of the IPv6 addresses of the configured IA. When the state of the configured IA is 
  /// in Dhcp6Bound, Dhcp6Renewing and Dhcp6Rebinding, the IPv6 addresses are usable.
  ///
  EFI_DHCP6_IA_ADDRESS         IaAddress[1];
} EFI_DHCP6_IA;

typedef struct {
  ///
  /// Pointer to the DHCPv6 unique identifier. The caller is responsible for freeing this buffer.
  ///
  EFI_DHCP6_DUID               *ClientId;
  ///
  /// Pointer to the configured IA of current instance. The caller can free this buffer after
  /// using it.
  ///
  EFI_DHCP6_IA                 *Ia;
} EFI_DHCP6_MODE_DATA;

/**
  EFI_DHCP6_CALLBACK is provided by the consumer of the EFI DHCPv6 Protocol instance to 
  intercept events that occurs in the DHCPv6 S.A.R.R process.

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance that is used to configure this 
                                callback function.
  @param[in]  Context           Pointer to the context that is initialized by EFI_DHCP6_PROTOCOL.Configure().
  @param[in]  CurrentState      The current state of the configured IA.
  @param[in]  Dhcp6Event        The event that occurs in the current state, which usually means a state transition.
  @param[in]  Packet            Pointer to the DHCPv6 packet that is about to be sent or has been received.
                                The EFI DHCPv6 Protocol instance is responsible for freeing the buffer. 
  @param[out] NewPacket         Pointer to the new DHCPv6 packet to overwrite the Packet. NewPacket can not 
                                share the buffer with Packet. If *NewPacket is not NULL, the EFI DHCPv6 
                                Protocol instance is responsible for freeing the buffer.

  @retval EFI_SUCCESS           Tell the EFI DHCPv6 Protocol instance to continue the DHCPv6 S.A.R.R process.
  @retval EFI_ABORTED           Tell the EFI DHCPv6 Protocol instance to abort the DHCPv6 S.A.R.R process, 
                                and the state of the configured IA will be transferred to Dhcp6Init.

**/
typedef 
EFI_STATUS 
(EFIAPI *EFI_DHCP6_CALLBACK)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN VOID                      *Context,
  IN EFI_DHCP6_STATE           CurrentState,
  IN EFI_DHCP6_EVENT           Dhcp6Event,
  IN EFI_DHCP6_PACKET          *Packet,        
  OUT EFI_DHCP6_PACKET         **NewPacket OPTIONAL
  );

typedef struct {
  ///
  /// The callback function is to intercept various events that occur in the DHCPv6 S.A.R.R 
  /// process. Set to NULL to ignore all those events.
  ///
  EFI_DHCP6_CALLBACK           Dhcp6Callback;
  ///
  /// Pointer to the context that will be passed to Dhcp6Callback.
  ///
  VOID                         *CallbackContext;
  ///
  /// Number of the DHCPv6 options in the OptionList.
  ///
  UINT32                       OptionCount;
  ///
  /// List of the DHCPv6 options to be included in Solicit and Request packet. The buffer 
  /// can be freed after EFI_DHCP6_PROTOCOL.Configure() returns. Ignored if 
  /// OptionCount is zero. OptionList should not contain Client Identifier option 
  /// and any IA option, which will be appended by EFI DHCPv6 Protocol instance 
  /// automatically. 
  ///
  EFI_DHCP6_PACKET_OPTION      **OptionList;
  ///
  /// The descriptor for the IA of the EFI DHCPv6 Protocol instance.
  ///
  EFI_DHCP6_IA_DESCRIPTOR      IaDescriptor;
  ///
  /// If not NULL, the event will be signaled when any IPv6 address information of the 
  /// configured IA is updated, including IPv6 address, preferred lifetime and valid 
  /// lifetime, or the DHCPv6 S.A.R.R process fails. Otherwise, Start(), 
  /// renewrebind(), decline(), release() and stop() will be blocking 
  /// operations, and they will wait for the exchange process completion or failure.
  ///
  EFI_EVENT                    IaInfoEvent;
  ///
  /// If TRUE, the EFI DHCPv6 Protocol instance is willing to accept Reconfigure packet. 
  /// Otherwise, it will ignore it. Reconfigure Accept option can not be specified through 
  /// OptionList parameter.
  ///
  BOOLEAN                      ReconfigureAccept;
  ///
  /// If TRUE, the EFI DHCPv6 Protocol instance will send Solicit packet with Rapid 
  /// Commit option. Otherwise, Rapid Commit option will not be included in Solicit 
  /// packet. Rapid Commit option can not be specified through OptionList parameter.
  ///
  BOOLEAN                      RapidCommit;
  ///
  /// Parameter to control Solicit packet retransmission behavior. The 
  /// buffer can be freed after EFI_DHCP6_PROTOCOL.Configure() returns.
  ///
  EFI_DHCP6_RETRANSMISSION     *SolicitRetransmission;
} EFI_DHCP6_CONFIG_DATA;

/**
  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[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance that is used to configure this 
                                callback function.
  @param[in]  Context           Pointer to the context that is initialized in the EFI_DHCP6_PROTOCOL.InfoRequest().
  @param[in]  Packet            Pointer to Reply packet that has been received. The EFI DHCPv6 Protocol instance is 
                                responsible for freeing the buffer.

  @retval EFI_SUCCESS           Tell the EFI DHCPv6 Protocol instance to finish Information Request exchange process.
  @retval EFI_NOT_READY         Tell the EFI DHCPv6 Protocol instance to continue Information Request exchange process.
  @retval EFI_ABORTED           Tell the EFI DHCPv6 Protocol instance to abort the Information Request exchange process.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_DHCP6_INFO_CALLBACK)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN VOID                      *Context,
  IN EFI_DHCP6_PACKET          *Packet
  );

/**
  Retrieve the current operating mode data and configuration data for the EFI DHCPv6 Protocol instance.

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.
  @param[out] Dhcp6ModeData     Pointer to the DHCPv6 mode data structure. The caller is responsible for freeing this 
                                structure and each reference buffer.
  @param[out] Dhcp6ConfigData   Pointer to the DHCPv6 configuration data structure. The caller is responsible for 
                                freeing this structure and each reference buffer.

  @retval EFI_SUCCESS           The mode data was returned.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Protocol instance has not been configured when Dhcp6ConfigData is not NULL.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE:
                                - This is NULL. 
                                - Both Dhcp6ConfigData and Dhcp6ModeData are NULL.

**/
typedef 
EFI_STATUS 
(EFIAPI *EFI_DHCP6_GET_MODE_DATA)(
  IN EFI_DHCP6_PROTOCOL        *This,
  OUT EFI_DHCP6_MODE_DATA      *Dhcp6ModeData OPTIONAL,
  OUT EFI_DHCP6_CONFIG_DATA    *Dhcp6ConfigData OPTIONAL
  );

/**
  Initialize or clean up the configuration data for the EFI DHCPv6 Protocol instance.

  The Configure() function is used to initialize or clean up the configuration data of the EFI 
  DHCPv6 Protocol instance.
  - When Dhcp6CfgData is not NULL and Configure() is called successfully, the 
    configuration data will be initialized in the EFI DHCPv6 Protocol instance and the state of the 
    configured IA will be transferred into Dhcp6Init.
  - When Dhcp6CfgData is NULL and Configure() is called successfully, the configuration 
    data will be cleaned up and no IA will be associated with the EFI DHCPv6 Protocol instance.

  To update the configuration data for an EFI DCHPv6 Protocol instance, the original data must be 
  cleaned up before setting the new configuration data.

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.
  @param[in]  Dhcp6CfgData      Pointer to the DHCPv6 configuration data structure.

  @retval EFI_SUCCESS           The mode data was returned.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE
                                - This is NULL. 
                                - OptionCount > 0 and OptionList is NULL.
                                - OptionList is not NULL, and Client Id option, Reconfigure Accept option,
                                  Rapid Commit option or any IA option is specified in the OptionList.
                                - IaDescriptor.Type is neither EFI_DHCP6_IA_TYPE_NA nor EFI_DHCP6_IA_TYPE_NA.
                                - IaDescriptor is not unique.
                                - Both IaInfoEvent and SolicitRetransimssion are NULL.
                                - SolicitRetransmission is not NULL, and both SolicitRetransimssion->Mrc and 
                                  SolicitRetransmission->Mrd are zero.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Protocol instance has been already configured 
                                when Dhcp6CfgData is not NULL.
                                The EFI DHCPv6 Protocol instance has already started the 
                                DHCPv6 S.A.R.R when Dhcp6CfgData is NULL.
  @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
  @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.

**/
typedef 
EFI_STATUS
(EFIAPI *EFI_DHCP6_CONFIGURE)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN EFI_DHCP6_CONFIG_DATA     *Dhcp6CfgData OPTIONAL
  );

/**
  Start the DHCPv6 S.A.R.R process.

  The Start() function starts the DHCPv6 S.A.R.R process. This function can be called only when 
  the state of the configured IA is in the Dhcp6Init state. If the DHCPv6 S.A.R.R process completes
  successfully, the state of the configured IA will be transferred through Dhcp6Selecting and 
  Dhcp6Requesting to Dhcp6Bound state. The update of the IPv6 addresses will be notified through 
  EFI_DHCP6_CONFIG_DATA.IaInfoEvent. At the time when each event occurs in this process, the 
  callback function set by EFI_DHCP6_PROTOCOL.Configure() will be called and the user can take 
  this opportunity to control the process. If EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL, the 
  Start() function call is a blocking operation. It will return after the DHCPv6 S.A.R.R process
  completes or aborted by users. If the process is aborted by system or network error, the state of
  the configured IA will be transferred to Dhcp6Init. The Start() function can be called again to
  restart the process.

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.

  @retval EFI_SUCCESS           The DHCPv6 S.A.R.R process is completed and at least one IPv6 
                                address has been bound to the configured IA when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL. 
                                The DHCPv6 S.A.R.R process is started when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is not NULL.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Child instance hasn't been configured.
  @retval EFI_INVALID_PARAMETER This is NULL.
  @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
  @retval EFI_ALREADY_STARTED   The DHCPv6 S.A.R.R process has already started.
  @retval EFI_DEVICE_ERROR      An unexpected network or system error occurred.
  @retval EFI_NO_RESPONSE       The DHCPv6 S.A.R.R process failed because of no response.
  @retval EFI_NO_MAPPING        No IPv6 address has been bound to the configured IA after the 
                                DHCPv6 S.A.R.R process.
  @retval EFI_ABORTED           The DHCPv6 S.A.R.R process aborted by user.
  @retval EFI_NO_MEDIA          There was a media error.

**/
typedef 
EFI_STATUS
(EFIAPI *EFI_DHCP6_START)(
  IN EFI_DHCP6_PROTOCOL        *This
  );

/**
  Request configuration information without the assignment of any IA addresses of the client.

  The InfoRequest() function is used to request configuration information without the assignment
  of any IPv6 address of the client. Client sends out Information Request packet to obtain 
  the required configuration information, and DHCPv6 server responds with Reply packet containing 
  the information for the client. The received Reply packet will be passed to the user by 
  ReplyCallback function. If user returns EFI_NOT_READY from ReplyCallback, the EFI DHCPv6
  Protocol instance will continue to receive other Reply packets unless timeout according to 
  the Retransmission parameter. Otherwise, the Information Request exchange process will be 
  finished successfully if user returns EFI_SUCCESS from ReplyCallback.

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.
  @param[in]  SendClientId      If TRUE, the EFI DHCPv6 Protocol instance will build Client
                                Identifier option and include it into Information Request
                                packet. If FALSE, Client Identifier option will not be included.
                                Client Identifier option can not be specified through OptionList 
                                parameter.
  @param[in]  OptionRequest     Pointer to the Option Request option in the Information Request
                                packet. Option Request option can not be specified through
                                OptionList parameter.
  @param[in]  OptionCount       Number of options in OptionList.
  @param[in]  OptionList        List of other DHCPv6 options. These options will be appended
                                to the Option Request option. The caller is responsible for
                                freeing this buffer. Type is defined in EFI_DHCP6_PROTOCOL.GetModeData().
  @param[in]  Retransmission    Parameter to control Information Request packet retransmission
                                behavior. The buffer can be freed after EFI_DHCP6_PROTOCOL.InfoRequest()
                                returns.
  @param[in]  TimeoutEvent      If not NULL, this event is signaled when the information request
                                exchange aborted because of no response. If NULL, the function
                                call is a blocking operation; and it will return after the 
                                information-request exchange process finish or aborted by users.
  @param[in]  ReplyCallback     The callback function is to intercept various events that occur
                                in the Information Request exchange process. It should not be
                                set to NULL.
  @param[in]  CallbackContext   Pointer to the context that will be passed to ReplyCallback.

  @retval EFI_SUCCESS           The DHCPv6 S.A.R.R process is completed and at least one IPv6 
  @retval EFI_SUCCESS           The DHCPv6 information request exchange process completed 
                                when TimeoutEvent is NULL. Information Request packet has been
                                sent to DHCPv6 server when TimeoutEvent is not NULL.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE:
                                - This is NULL. 
                                - OptionRequest is NULL or OptionRequest->OpCode is invalid.
                                - OptionCount > 0 and OptionList is NULL.
                                - OptionList is not NULL, and Client Identify option or 
                                  Option Request option is specified in the OptionList.
                                - Retransimssion is NULL.
                                - Both Retransimssion->Mrc and Retransmission->Mrd are zero.
                                - ReplyCallback is NULL.
  @retval EFI_DEVICE_ERROR      An unexpected network or system error occurred.
  @retval EFI_NO_RESPONSE       The DHCPv6 information request exchange process failed 
                                because of no response, or not all requested-options are 
                                responded by DHCPv6 servers when Timeout happened.
  @retval EFI_ABORTED           The DHCPv6 information request exchange process aborted by user.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_DHCP6_INFO_REQUEST)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN BOOLEAN                   SendClientId,
  IN EFI_DHCP6_PACKET_OPTION   *OptionRequest,
  IN UINT32                    OptionCount,
  IN EFI_DHCP6_PACKET_OPTION   *OptionList[] OPTIONAL,
  IN EFI_DHCP6_RETRANSMISSION  *Retransmission, 
  IN EFI_EVENT                 TimeoutEvent OPTIONAL,
  IN EFI_DHCP6_INFO_CALLBACK   ReplyCallback,
  IN VOID                      *CallbackContext OPTIONAL
  );

/**
  Manually extend the valid and preferred lifetimes for the IPv6 addresses of the configured
  IA and update other configuration parameters by sending Renew or Rebind packet.

  The RenewRebind() function is used to manually extend the valid and preferred lifetimes for the 
  IPv6 addresses of the configured IA and update other configuration parameters by sending Renew or 
  Rebind packet. 
  - When RebindRequest is FALSE and the state of the configured IA is Dhcp6Bound, it 
  will send Renew packet to the previously DHCPv6 server and transfer the state of the configured 
  IA to Dhcp6Renewing. If valid Reply packet received, the state transfers to Dhcp6Bound 
  and the valid and preferred timer restarts. If fails, the state transfers to Dhcp6Bound but the 
  timer continues. 
  - When RebindRequest is TRUE and the state of the configured IA is Dhcp6Bound, it will 
  send Rebind packet. If valid Reply packet received, the state transfers to Dhcp6Bound and the 
  valid and preferred timer restarts. If fails, the state transfers to Dhcp6Init and the IA can't
  be used.

  @param[in]  This              Pointer to the EFI_DHCP4_PROTOCOL instance.
  @param[in]  RebindRequest     If TRUE, it will send Rebind packet and enter the Dhcp6Rebinding state. 
                                Otherwise, it will send Renew packet and enter the Dhcp6Renewing state.

  @retval EFI_SUCCESS           The DHCPv6 renew/rebind exchange process has completed and at 
                                least one IPv6 address of the configured IA has been bound again
                                when EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL. 
                                The EFI DHCPv6 Protocol instance has sent Renew or Rebind packet 
                                when EFI_DHCP6_CONFIG_DATA.IaInfoEvent is not NULL.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Child instance hasn't been configured, or the state
                                of the configured IA is not in Dhcp6Bound.
  @retval EFI_ALREADY_STARTED   The state of the configured IA has already entered Dhcp6Renewing 
                                when RebindRequest is FALSE. 
                                The state of the configured IA has already entered Dhcp6Rebinding 
                                when RebindRequest is TRUE.
  @retval EFI_INVALID_PARAMETER This is NULL.
  @retval EFI_DEVICE_ERROR      An unexpected system or system error occurred.
  @retval EFI_NO_RESPONSE       The DHCPv6 renew/rebind exchange process failed because of no response.
  @retval EFI_NO_MAPPING        No IPv6 address has been bound to the configured IA after the DHCPv6 
                                renew/rebind exchange process.
  @retval EFI_ABORTED           The DHCPv6 renew/rebind exchange process aborted by user.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_DHCP6_RENEW_REBIND)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN BOOLEAN                   RebindRequest
  );

/**
  Inform that one or more IPv6 addresses assigned by a server are already in use by
  another node.

  The Decline() function is used to manually decline the assignment of IPv6 addresses, which 
  have been already used by another node. If all IPv6 addresses of the configured IA are declined 
  through this function, the state of the IA will switch through Dhcp6Declining to Dhcp6Init, 
  otherwise, the state of the IA will restore to Dhcp6Bound after the declining process. The 
  Decline() can only be called when the IA is in Dhcp6Bound state. If the 
  EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL, this function is a blocking operation. It 
  will return after the declining process finishes, or aborted by user.

  @param[in]  This              Pointer to the EFI_DHCP4_PROTOCOL instance.
  @param[in]  AddressCount      Number of declining IPv6 addresses. 
  @param[in]  Addresses         Pointer to the buffer stored all the declining IPv6 addresses.

  @retval EFI_SUCCESS           The DHCPv6 decline exchange process has completed when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL.
                                The EFI DHCPv6 Protocol instance has sent Decline packet when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is not NULL.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE
                                - This is NULL.  
                                - AddressCount is zero or Addresses is NULL.
  @retval EFI_NOT_FOUND         Any specified IPv6 address is not correlated with the configured IA 
                                for this instance.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Child instance hasn't been configured, or the 
                                state of the configured IA is not in Dhcp6Bound.
  @retval EFI_DEVICE_ERROR      An unexpected network or system error occurred.
  @retval EFI_ABORTED           The DHCPv6 decline exchange process aborted by user.

**/
typedef 
EFI_STATUS
(EFIAPI *EFI_DHCP6_DECLINE)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN UINT32                    AddressCount,
  IN EFI_IPv6_ADDRESS          *Addresses
  );

/**
  Release one or more IPv6 addresses associated with the configured IA for current instance.

  The Release() function is used to manually release the one or more IPv6 address. If AddressCount
  is zero, it will release all IPv6 addresses of the configured IA. If all IPv6 addresses of the IA
  are released through this function, the state of the IA will switch through Dhcp6Releasing to 
  Dhcp6Init, otherwise, the state of the IA will restore to Dhcp6Bound after the releasing process.
  The Release() can only be called when the IA is in Dhcp6Bound state. If the
  EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL, the function is a blocking operation. It will return
  after the releasing process finishes, or aborted by user. 

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.
  @param[in]  AddressCount      Number of releasing IPv6 addresses. 
  @param[in]  Addresses         Pointer to the buffer stored all the releasing IPv6 addresses.
                                Ignored if AddressCount is zero.
  @retval EFI_SUCCESS           The DHCPv6 release exchange process has completed when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL.
                                The EFI DHCPv6 Protocol instance has sent Release packet when 
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is not NULL.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE
                                - This is NULL.  
                                - AddressCount is not zero or Addresses is NULL.
  @retval EFI_NOT_FOUND         Any specified IPv6 address is not correlated with the configured
                                IA for this instance.
  @retval EFI_ACCESS_DENIED     The EFI DHCPv6 Child instance hasn't been configured, or the 
                                state of the configured IA is not in Dhcp6Bound.
  @retval EFI_DEVICE_ERROR      An unexpected network or system error occurred.
  @retval EFI_ABORTED           The DHCPv6 release exchange process aborted by user. 

**/
typedef 
EFI_STATUS
(EFIAPI *EFI_DHCP6_RELEASE)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN UINT32                    AddressCount,
  IN EFI_IPv6_ADDRESS          *Addresses
  );

/**
  Stop the DHCPv6 S.A.R.R process.

  The Stop() function is used to stop the DHCPv6 S.A.R.R process. If this function is called
  successfully, all the IPv6 addresses of the configured IA will be released and the state of
  the configured IA will be transferred to Dhcp6Init.   

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.

  @retval EFI_SUCCESS           The DHCPv6 S.A.R.R process has been stopped when
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is NULL.
                                The EFI DHCPv6 Protocol instance has sent Release packet if
                                need release or has been stopped if needn't, when
                                EFI_DHCP6_CONFIG_DATA.IaInfoEvent is not NULL.
  @retval EFI_INVALID_PARAMETER This is NULL.

**/
typedef 
EFI_STATUS
(EFIAPI *EFI_DHCP6_STOP)(
  IN EFI_DHCP6_PROTOCOL        *This
  );

/**
  Parse the option data in the DHCPv6 packet.

  The Parse() function is used to retrieve the option list in the DHCPv6 packet. 

  @param[in]  This              Pointer to the EFI_DHCP6_PROTOCOL instance.

  @param[in]  Packet            Pointer to packet to be parsed.
  @param[in]  OptionCount       On input, the number of entries in the PacketOptionList.
                                On output, the number of DHCPv6 options in the Packet.
  @param[in]  PacketOptionList  List of pointers to the DHCPv6 options in the Packet.
                                The OpCode and OpLen in EFI_DHCP6_PACKET_OPTION are
                                both stored in network byte order.
  @retval EFI_SUCCESS           The packet was successfully parsed.
  @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE
                                - This is NULL.
                                - Packet is NULL.
                                - Packet is not a well-formed DHCPv6 packet.
                                - OptionCount is NULL.
                                - *OptionCount is not zero and PacketOptionList is NULL.
  @retval EFI_BUFFER_TOO_SMALL  *OptionCount is smaller than the number of options that were 
                                found in the Packet.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_DHCP6_PARSE)(
  IN EFI_DHCP6_PROTOCOL        *This,
  IN EFI_DHCP6_PACKET          *Packet,
  IN OUT UINT32                *OptionCount,
  OUT EFI_DHCP6_PACKET_OPTION  *PacketOptionList[] OPTIONAL
);

///
/// The EFI DHCPv6 Protocol is used to get IPv6 addresses and other configuration parameters
/// from DHCPv6 servers.
///
struct _EFI_DHCP6_PROTOCOL {
  EFI_DHCP6_GET_MODE_DATA      GetModeData;
  EFI_DHCP6_CONFIGURE          Configure;
  EFI_DHCP6_START              Start;
  EFI_DHCP6_INFO_REQUEST       InfoRequest;
  EFI_DHCP6_RENEW_REBIND       RenewRebind;
  EFI_DHCP6_DECLINE            Decline;
  EFI_DHCP6_RELEASE            Release;
  EFI_DHCP6_STOP               Stop;
  EFI_DHCP6_PARSE              Parse;
};

extern EFI_GUID gEfiDhcp6ProtocolGuid;
extern EFI_GUID gEfiDhcp6ServiceBindingProtocolGuid;

#endif