Ip4.h

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/** @file
  This file defines the EFI IPv4 (Internet Protocol version 4)
  Protocol interface. It is split into the following three main
  sections:
  - EFI IPv4 Service Binding Protocol
  - EFI IPv4 Variable (deprecated in UEFI 2.4B)
  - EFI IPv4 Protocol.
  The EFI IPv4 Protocol provides basic network IPv4 packet I/O services,
  which includes support foR a subset of the Internet Control Message
  Protocol (ICMP) and may include support for the Internet Group Management
  Protocol (IGMP).
 
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
 
  @par Revision Reference:
  This Protocol is introduced in UEFI Specification 2.0.
 
**/
 
#pragma once
 
FILE_LICENCE ( BSD2_PATENT );
FILE_SECBOOT ( PERMITTED );
 
#include <ipxe/efi/Protocol/ManagedNetwork.h>
 
#define EFI_IP4_SERVICE_BINDING_PROTOCOL_GUID \
  { \
    0xc51711e7, 0xb4bf, 0x404a, {0xbf, 0xb8, 0x0a, 0x04, 0x8e, 0xf1, 0xff, 0xe4 } \
  }
 
#define EFI_IP4_PROTOCOL_GUID \
  { \
    0x41d94cd2, 0x35b6, 0x455a, {0x82, 0x58, 0xd4, 0xe5, 0x13, 0x34, 0xaa, 0xdd } \
  }
 
typedef struct _EFI_IP4_PROTOCOL EFI_IP4_PROTOCOL;
 
///
/// EFI_IP4_ADDRESS_PAIR is deprecated in the UEFI 2.4B and should not be used any more.
/// The definition in here is only present to provide backwards compatability.
///
typedef struct {
  EFI_HANDLE          InstanceHandle;
  EFI_IPv4_ADDRESS    Ip4Address;
  EFI_IPv4_ADDRESS    SubnetMask;
} EFI_IP4_ADDRESS_PAIR;
 
///
/// EFI_IP4_VARIABLE_DATA is deprecated in the UEFI 2.4B and should not be used any more.
/// The definition in here is only present to provide backwards compatability.
///
typedef struct {
  EFI_HANDLE              DriverHandle;
  UINT32                  AddressCount;
  EFI_IP4_ADDRESS_PAIR    AddressPairs[1];
} EFI_IP4_VARIABLE_DATA;
 
typedef struct {
  ///
  /// The default IPv4 protocol packets to send and receive. Ignored
  /// when AcceptPromiscuous is TRUE.
  ///
  UINT8               DefaultProtocol;
  ///
  /// Set to TRUE to receive all IPv4 packets that get through the receive filters.
  /// Set to FALSE to receive only the DefaultProtocol IPv4
  /// packets that get through the receive filters.
  ///
  BOOLEAN             AcceptAnyProtocol;
  ///
  /// Set to TRUE to receive ICMP error report packets. Ignored when
  /// AcceptPromiscuous or AcceptAnyProtocol is TRUE.
  ///
  BOOLEAN             AcceptIcmpErrors;
  ///
  /// Set to TRUE to receive broadcast IPv4 packets. Ignored when
  /// AcceptPromiscuous is TRUE.
  /// Set to FALSE to stop receiving broadcast IPv4 packets.
  ///
  BOOLEAN             AcceptBroadcast;
  ///
  /// Set to TRUE to receive all IPv4 packets that are sent to any
  /// hardware address or any protocol address.
  /// Set to FALSE to stop receiving all promiscuous IPv4 packets
  ///
  BOOLEAN             AcceptPromiscuous;
  ///
  /// Set to TRUE to use the default IPv4 address and default routing table.
  ///
  BOOLEAN             UseDefaultAddress;
  ///
  /// The station IPv4 address that will be assigned to this EFI IPv4Protocol instance.
  ///
  EFI_IPv4_ADDRESS    StationAddress;
  ///
  /// The subnet address mask that is associated with the station address.
  ///
  EFI_IPv4_ADDRESS    SubnetMask;
  ///
  /// TypeOfService field in transmitted IPv4 packets.
  ///
  UINT8               TypeOfService;
  ///
  /// TimeToLive field in transmitted IPv4 packets.
  ///
  UINT8               TimeToLive;
  ///
  /// State of the DoNotFragment bit in transmitted IPv4 packets.
  ///
  BOOLEAN             DoNotFragment;
  ///
  /// Set to TRUE to send and receive unformatted packets. The other
  /// IPv4 receive filters are still applied. Fragmentation is disabled for RawData mode.
  ///
  BOOLEAN             RawData;
  ///
  /// The timer timeout value (number of microseconds) for the
  /// receive timeout event to be associated with each assembled
  /// packet. Zero means do not drop assembled packets.
  ///
  UINT32              ReceiveTimeout;
  ///
  /// The timer timeout value (number of microseconds) for the
  /// transmit timeout event to be associated with each outgoing
  /// packet. Zero means do not drop outgoing packets.
  ///
  UINT32              TransmitTimeout;
} EFI_IP4_CONFIG_DATA;
 
typedef struct {
  EFI_IPv4_ADDRESS    SubnetAddress;
  EFI_IPv4_ADDRESS    SubnetMask;
  EFI_IPv4_ADDRESS    GatewayAddress;
} EFI_IP4_ROUTE_TABLE;
 
typedef struct {
  UINT8    Type;
  UINT8    Code;
} EFI_IP4_ICMP_TYPE;
 
typedef struct {
  ///
  /// Set to TRUE after this EFI IPv4 Protocol instance has been successfully configured.
  ///
  BOOLEAN                IsStarted;
  ///
  /// The maximum packet size, in bytes, of the packet which the upper layer driver could feed.
  ///
  UINT32                 MaxPacketSize;
  ///
  /// Current configuration settings.
  ///
  EFI_IP4_CONFIG_DATA    ConfigData;
  ///
  /// Set to TRUE when the EFI IPv4 Protocol instance has a station address and subnet mask.
  ///
  BOOLEAN                IsConfigured;
  ///
  /// Number of joined multicast groups.
  ///
  UINT32                 GroupCount;
  ///
  /// List of joined multicast group addresses.
  ///
  EFI_IPv4_ADDRESS       *GroupTable;
  ///
  /// Number of entries in the routing table.
  ///
  UINT32                 RouteCount;
  ///
  /// Routing table entries.
  ///
  EFI_IP4_ROUTE_TABLE    *RouteTable;
  ///
  /// Number of entries in the supported ICMP types list.
  ///
  UINT32                 IcmpTypeCount;
  ///
  /// Array of ICMP types and codes that are supported by this EFI IPv4 Protocol driver
  ///
  EFI_IP4_ICMP_TYPE      *IcmpTypeList;
} EFI_IP4_MODE_DATA;
 
#pragma pack(1)
 
typedef struct {
  UINT8               HeaderLength : 4;
  UINT8               Version      : 4;
  UINT8               TypeOfService;
  UINT16              TotalLength;
  UINT16              Identification;
  UINT16              Fragmentation;
  UINT8               TimeToLive;
  UINT8               Protocol;
  UINT16              Checksum;
  EFI_IPv4_ADDRESS    SourceAddress;
  EFI_IPv4_ADDRESS    DestinationAddress;
} EFI_IP4_HEADER;
#pragma pack()
 
typedef struct {
  UINT32    FragmentLength;
  VOID      *FragmentBuffer;
} EFI_IP4_FRAGMENT_DATA;
 
typedef struct {
  EFI_TIME                 TimeStamp;
  EFI_EVENT                RecycleSignal;
  UINT32                   HeaderLength;
  EFI_IP4_HEADER           *Header;
  UINT32                   OptionsLength;
  VOID                     *Options;
  UINT32                   DataLength;
  UINT32                   FragmentCount;
  EFI_IP4_FRAGMENT_DATA    FragmentTable[1];
} EFI_IP4_RECEIVE_DATA;
 
typedef struct {
  EFI_IPv4_ADDRESS    SourceAddress;
  EFI_IPv4_ADDRESS    GatewayAddress;
  UINT8               Protocol;
  UINT8               TypeOfService;
  UINT8               TimeToLive;
  BOOLEAN             DoNotFragment;
} EFI_IP4_OVERRIDE_DATA;
 
typedef struct {
  EFI_IPv4_ADDRESS         DestinationAddress;
  EFI_IP4_OVERRIDE_DATA    *OverrideData;    // OPTIONAL
  UINT32                   OptionsLength;    // OPTIONAL
  VOID                     *OptionsBuffer;   // OPTIONAL
  UINT32                   TotalDataLength;
  UINT32                   FragmentCount;
  EFI_IP4_FRAGMENT_DATA    FragmentTable[1];
} EFI_IP4_TRANSMIT_DATA;
 
typedef struct {
  ///
  /// This Event will be signaled after the Status field is updated
  /// by the EFI IPv4 Protocol driver. The type of Event must be
  /// EFI_NOTIFY_SIGNAL. The Task Priority Level (TPL) of
  /// Event must be lower than or equal to TPL_CALLBACK.
  ///
  EFI_EVENT     Event;
  ///
  /// The status that is returned to the caller at the end of the operation
  /// to indicate whether this operation completed successfully.
  ///
  EFI_STATUS    Status;
  union {
    ///
    /// When this token is used for receiving, RxData is a pointer to the EFI_IP4_RECEIVE_DATA.
    ///
    EFI_IP4_RECEIVE_DATA     *RxData;
    ///
    /// When this token is used for transmitting, TxData is a pointer to the EFI_IP4_TRANSMIT_DATA.
    ///
    EFI_IP4_TRANSMIT_DATA    *TxData;
  } Packet;
} EFI_IP4_COMPLETION_TOKEN;
 
/**
  Gets the current operational settings for this instance of the EFI IPv4 Protocol driver.
 
  The GetModeData() function returns the current operational mode data for this
  driver instance. The data fields in EFI_IP4_MODE_DATA are read only. This
  function is used optionally to retrieve the operational mode data of underlying
  networks or drivers.
 
  @param  This          The pointer to the EFI_IP4_PROTOCOL instance.
  @param  Ip4ModeData   The pointer to the EFI IPv4 Protocol mode data structure.
  @param  MnpConfigData The pointer to the managed network configuration data structure.
  @param  SnpModeData   The pointer to the simple network mode data structure.
 
  @retval EFI_SUCCESS           The operation completed successfully.
  @retval EFI_INVALID_PARAMETER This is NULL.
  @retval EFI_OUT_OF_RESOURCES  The required mode data could not be allocated.
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_GET_MODE_DATA)(
  IN CONST  EFI_IP4_PROTOCOL                *This,
  OUT       EFI_IP4_MODE_DATA               *Ip4ModeData     OPTIONAL,
  OUT       EFI_MANAGED_NETWORK_CONFIG_DATA *MnpConfigData   OPTIONAL,
  OUT       EFI_SIMPLE_NETWORK_MODE         *SnpModeData     OPTIONAL
  );
 
/**
  Assigns an IPv4 address and subnet mask to this EFI IPv4 Protocol driver instance.
 
  The Configure() function is used to set, change, or reset the operational
  parameters and filter settings for this EFI IPv4 Protocol instance. Until these
  parameters have been set, no network traffic can be sent or received by this
  instance. Once the parameters have been reset (by calling this function with
  IpConfigData set to NULL), no more traffic can be sent or received until these
  parameters have been set again. Each EFI IPv4 Protocol instance can be started
  and stopped independently of each other by enabling or disabling their receive
  filter settings with the Configure() function.
 
  When IpConfigData.UseDefaultAddress is set to FALSE, the new station address will
  be appended as an alias address into the addresses list in the EFI IPv4 Protocol
  driver. While set to TRUE, Configure() will trigger the EFI_IP4_CONFIG_PROTOCOL
  to retrieve the default IPv4 address if it is not available yet. Clients could
  frequently call GetModeData() to check the status to ensure that the default IPv4
  address is ready.
 
  If operational parameters are reset or changed, any pending transmit and receive
  requests will be cancelled. Their completion token status will be set to EFI_ABORTED
  and their events will be signaled.
 
  @param  This         The pointer to the EFI_IP4_PROTOCOL instance.
  @param  IpConfigData The pointer to the EFI IPv4 Protocol configuration data structure.
 
  @retval EFI_SUCCESS           The driver instance was successfully opened.
  @retval EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP,
                                RARP, etc.) is not finished yet.
  @retval EFI_INVALID_PARAMETER One or more of the following conditions is TRUE:
                                This is NULL.
                                IpConfigData.StationAddress is not a unicast IPv4 address.
                                IpConfigData.SubnetMask is not a valid IPv4 subnet
  @retval EFI_UNSUPPORTED       One or more of the following conditions is TRUE:
                                A configuration protocol (DHCP, BOOTP, RARP, etc.) could
                                not be located when clients choose to use the default IPv4
                                address. This EFI IPv4 Protocol implementation does not
                                support this requested filter or timeout setting.
  @retval EFI_OUT_OF_RESOURCES  The EFI IPv4 Protocol driver instance data could not be allocated.
  @retval EFI_ALREADY_STARTED   The interface is already open and must be stopped before the
                                IPv4 address or subnet mask can be changed. The interface must
                                also be stopped when switching to/from raw packet mode.
  @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred. The EFI IPv4
                                Protocol driver instance is not opened.
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_CONFIGURE)(
  IN EFI_IP4_PROTOCOL    *This,
  IN EFI_IP4_CONFIG_DATA *IpConfigData     OPTIONAL
  );
 
/**
  Joins and leaves multicast groups.
 
  The Groups() function is used to join and leave multicast group sessions. Joining
  a group will enable reception of matching multicast packets. Leaving a group will
  disable the multicast packet reception.
 
  If JoinFlag is FALSE and GroupAddress is NULL, all joined groups will be left.
 
  @param  This                  The pointer to the EFI_IP4_PROTOCOL instance.
  @param  JoinFlag              Set to TRUE to join the multicast group session and FALSE to leave.
  @param  GroupAddress          The pointer to the IPv4 multicast address.
 
  @retval EFI_SUCCESS           The operation completed successfully.
  @retval EFI_INVALID_PARAMETER One or more of the following is TRUE:
                                - This is NULL.
                                - JoinFlag is TRUE and GroupAddress is NULL.
                                - GroupAddress is not NULL and *GroupAddress is
                                  not a multicast IPv4 address.
  @retval EFI_NOT_STARTED       This instance has not been started.
  @retval EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP,
                                RARP, etc.) is not finished yet.
  @retval EFI_OUT_OF_RESOURCES  System resources could not be allocated.
  @retval EFI_UNSUPPORTED       This EFI IPv4 Protocol implementation does not support multicast groups.
  @retval EFI_ALREADY_STARTED   The group address is already in the group table (when
                                JoinFlag is TRUE).
  @retval EFI_NOT_FOUND         The group address is not in the group table (when JoinFlag is FALSE).
  @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_GROUPS)(
  IN EFI_IP4_PROTOCOL    *This,
  IN BOOLEAN             JoinFlag,
  IN EFI_IPv4_ADDRESS    *GroupAddress  OPTIONAL
  );
 
/**
  Adds and deletes routing table entries.
 
  The Routes() function adds a route to or deletes a route from the routing table.
 
  Routes are determined by comparing the SubnetAddress with the destination IPv4
  address arithmetically AND-ed with the SubnetMask. The gateway address must be
  on the same subnet as the configured station address.
 
  The default route is added with SubnetAddress and SubnetMask both set to 0.0.0.0.
  The default route matches all destination IPv4 addresses that do not match any
  other routes.
 
  A GatewayAddress that is zero is a nonroute. Packets are sent to the destination
  IP address if it can be found in the ARP cache or on the local subnet. One automatic
  nonroute entry will be inserted into the routing table for outgoing packets that
  are addressed to a local subnet (gateway address of 0.0.0.0).
 
  Each EFI IPv4 Protocol instance has its own independent routing table. Those EFI
  IPv4 Protocol instances that use the default IPv4 address will also have copies
  of the routing table that was provided by the EFI_IP4_CONFIG_PROTOCOL, and these
  copies will be updated whenever the EIF IPv4 Protocol driver reconfigures its
  instances. As a result, client modification to the routing table will be lost.
 
  @param  This                   The pointer to the EFI_IP4_PROTOCOL instance.
  @param  DeleteRoute            Set to TRUE to delete this route from the routing table. Set to
                                 FALSE to add this route to the routing table. SubnetAddress
                                 and SubnetMask are used as the key to each route entry.
  @param  SubnetAddress          The address of the subnet that needs to be routed.
  @param  SubnetMask             The subnet mask of SubnetAddress.
  @param  GatewayAddress         The unicast gateway IPv4 address for this route.
 
  @retval EFI_SUCCESS            The operation completed successfully.
  @retval EFI_NOT_STARTED        The driver instance has not been started.
  @retval EFI_NO_MAPPING         When using the default address, configuration (DHCP, BOOTP,
                                 RARP, etc.) is not finished yet.
  @retval EFI_INVALID_PARAMETER  One or more of the following conditions is TRUE:
                                 - This is NULL.
                                 - SubnetAddress is NULL.
                                 - SubnetMask is NULL.
                                 - GatewayAddress is NULL.
                                 - *SubnetAddress is not a valid subnet address.
                                 - *SubnetMask is not a valid subnet mask.
                                 - *GatewayAddress is not a valid unicast IPv4 address.
  @retval EFI_OUT_OF_RESOURCES   Could not add the entry to the routing table.
  @retval EFI_NOT_FOUND          This route is not in the routing table (when DeleteRoute is TRUE).
  @retval EFI_ACCESS_DENIED      The route is already defined in the routing table (when
                                 DeleteRoute is FALSE).
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_ROUTES)(
  IN EFI_IP4_PROTOCOL    *This,
  IN BOOLEAN             DeleteRoute,
  IN EFI_IPv4_ADDRESS    *SubnetAddress,
  IN EFI_IPv4_ADDRESS    *SubnetMask,
  IN EFI_IPv4_ADDRESS    *GatewayAddress
  );
 
/**
  Places outgoing data packets into the transmit queue.
 
  The Transmit() function places a sending request in the transmit queue of this
  EFI IPv4 Protocol instance. Whenever the packet in the token is sent out or some
  errors occur, the event in the token will be signaled and the status is updated.
 
  @param  This  The pointer to the EFI_IP4_PROTOCOL instance.
  @param  Token The pointer to the transmit token.
 
  @retval  EFI_SUCCESS           The data has been queued for transmission.
  @retval  EFI_NOT_STARTED       This instance has not been started.
  @retval  EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP,
                                 RARP, etc.) is not finished yet.
  @retval  EFI_INVALID_PARAMETER One or more pameters are invalid.
  @retval  EFI_ACCESS_DENIED     The transmit completion token with the same Token.Event
                                 was already in the transmit queue.
  @retval  EFI_NOT_READY         The completion token could not be queued because the transmit
                                 queue is full.
  @retval  EFI_NOT_FOUND         Not route is found to destination address.
  @retval  EFI_OUT_OF_RESOURCES  Could not queue the transmit data.
  @retval  EFI_BUFFER_TOO_SMALL  Token.Packet.TxData.TotalDataLength is too
                                 short to transmit.
  @retval  EFI_BAD_BUFFER_SIZE   The length of the IPv4 header + option length + total data length is
                                 greater than MTU (or greater than the maximum packet size if
                                 Token.Packet.TxData.OverrideData.
                                 DoNotFragment is TRUE.)
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_TRANSMIT)(
  IN EFI_IP4_PROTOCOL          *This,
  IN EFI_IP4_COMPLETION_TOKEN  *Token
  );
 
/**
  Places a receiving request into the receiving queue.
 
  The Receive() function places a completion token into the receive packet queue.
  This function is always asynchronous.
 
  The Token.Event field in the completion token must be filled in by the caller
  and cannot be NULL. When the receive operation completes, the EFI IPv4 Protocol
  driver updates the Token.Status and Token.Packet.RxData fields and the Token.Event
  is signaled.
 
  @param  This  The pointer to the EFI_IP4_PROTOCOL instance.
  @param  Token The pointer to a token that is associated with the receive data descriptor.
 
  @retval EFI_SUCCESS           The receive completion token was cached.
  @retval EFI_NOT_STARTED       This EFI IPv4 Protocol instance has not been started.
  @retval EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP, RARP, etc.)
                                is not finished yet.
  @retval EFI_INVALID_PARAMETER One or more of the following conditions is TRUE:
                                - This is NULL.
                                - Token is NULL.
                                - Token.Event is NULL.
  @retval EFI_OUT_OF_RESOURCES  The receive completion token could not be queued due to a lack of system
                                resources (usually memory).
  @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
                                The EFI IPv4 Protocol instance has been reset to startup defaults.
  @retval EFI_ACCESS_DENIED     The receive completion token with the same Token.Event was already
                                in the receive queue.
  @retval EFI_NOT_READY         The receive request could not be queued because the receive queue is full.
  @retval EFI_ICMP_ERROR        An ICMP error packet was received.
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_RECEIVE)(
  IN EFI_IP4_PROTOCOL          *This,
  IN EFI_IP4_COMPLETION_TOKEN  *Token
  );
 
/**
  Abort an asynchronous transmit or receive request.
 
  The Cancel() function is used to abort a pending transmit or receive request.
  If the token is in the transmit or receive request queues, after calling this
  function, Token->Status will be set to EFI_ABORTED and then Token->Event will
  be signaled. If the token is not in one of the queues, which usually means the
  asynchronous operation has completed, this function will not signal the token
  and EFI_NOT_FOUND is returned.
 
  @param  This  The pointer to the EFI_IP4_PROTOCOL instance.
  @param  Token The pointer to a token that has been issued by
                EFI_IP4_PROTOCOL.Transmit() or
                EFI_IP4_PROTOCOL.Receive(). If NULL, all pending
                tokens are aborted. Type EFI_IP4_COMPLETION_TOKEN is
                defined in EFI_IP4_PROTOCOL.Transmit().
 
  @retval EFI_SUCCESS           The asynchronous I/O request was aborted and
                                Token->Event was signaled. When Token is NULL, all
                                pending requests were aborted and their events were signaled.
  @retval EFI_INVALID_PARAMETER This is NULL.
  @retval EFI_NOT_STARTED       This instance has not been started.
  @retval EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP,
                                RARP, etc.) is not finished yet.
  @retval EFI_NOT_FOUND         When Token is not NULL, the asynchronous I/O request was
                                not found in the transmit or receive queue. It has either completed
                                or was not issued by Transmit() and Receive().
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_CANCEL)(
  IN EFI_IP4_PROTOCOL          *This,
  IN EFI_IP4_COMPLETION_TOKEN  *Token OPTIONAL
  );
 
/**
  Polls for incoming data packets and processes outgoing data packets.
 
  The Poll() function polls for incoming data packets and processes outgoing data
  packets. Network drivers and applications can call the EFI_IP4_PROTOCOL.Poll()
  function to increase the rate that data packets are moved between the communications
  device and the transmit and receive queues.
 
  In some systems the periodic timer event may not poll the underlying communications
  device fast enough to transmit and/or receive all data packets without missing
  incoming packets or dropping outgoing packets. Drivers and applications that are
  experiencing packet loss should try calling the EFI_IP4_PROTOCOL.Poll() function
  more often.
 
  @param  This The pointer to the EFI_IP4_PROTOCOL instance.
 
  @retval  EFI_SUCCESS           Incoming or outgoing data was processed.
  @retval  EFI_NOT_STARTED       This EFI IPv4 Protocol instance has not been started.
  @retval  EFI_NO_MAPPING        When using the default address, configuration (DHCP, BOOTP,
                                 RARP, etc.) is not finished yet.
  @retval  EFI_INVALID_PARAMETER This is NULL.
  @retval  EFI_DEVICE_ERROR      An unexpected system or network error occurred.
  @retval  EFI_NOT_READY         No incoming or outgoing data is processed.
  @retval  EFI_TIMEOUT           Data was dropped out of the transmit and/or receive queue.
                                 Consider increasing the polling rate.
 
**/
typedef
EFI_STATUS
(EFIAPI *EFI_IP4_POLL)(
  IN EFI_IP4_PROTOCOL          *This
  );
 
///
/// The EFI IPv4 Protocol implements a simple packet-oriented interface that can be
/// used by drivers, daemons, and applications to transmit and receive network packets.
///
struct _EFI_IP4_PROTOCOL {
  EFI_IP4_GET_MODE_DATA    GetModeData;
  EFI_IP4_CONFIGURE        Configure;
  EFI_IP4_GROUPS           Groups;
  EFI_IP4_ROUTES           Routes;
  EFI_IP4_TRANSMIT         Transmit;
  EFI_IP4_RECEIVE          Receive;
  EFI_IP4_CANCEL           Cancel;
  EFI_IP4_POLL             Poll;
};
 
extern EFI_GUID  gEfiIp4ServiceBindingProtocolGuid;
extern EFI_GUID  gEfiIp4ProtocolGuid;