MdePkg/Include/Protocol/Dhcp4.h

   1 /** @file
   2   EFI_DHCP4_PROTOCOL as defined in UEFI 2.0.
   3   EFI_DHCP4_SERVICE_BINDING_PROTOCOL as defined in UEFI 2.0.
   4   These protocols are used to collect configuration information for the EFI IPv4 Protocol
   5   drivers and to provide DHCPv4 server and PXE boot server discovery services.
   6
   7   Copyright (c) 2006 - 2008, Intel Corporation
   8   All rights reserved. This program and the accompanying materials
   9   are licensed and made available under the terms and conditions of the BSD License
  10   which accompanies this distribution.  The full text of the license may be found at
  11   http://opensource.org/licenses/bsd-license.php
  12
  13   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16 **/
  17
  18 #ifndef __EFI_DHCP4_PROTOCOL_H__
  19 #define __EFI_DHCP4_PROTOCOL_H__
  20
  21 #define EFI_DHCP4_PROTOCOL_GUID \
  22   { \
  23     0x8a219718, 0x4ef5, 0x4761, {0x91, 0xc8, 0xc0, 0xf0, 0x4b, 0xda, 0x9e, 0x56 } \
  24   }
  25
  26 #define EFI_DHCP4_SERVICE_BINDING_PROTOCOL_GUID \
  27   { \
  28     0x9d9a39d8, 0xbd42, 0x4a73, {0xa4, 0xd5, 0x8e, 0xe9, 0x4b, 0xe1, 0x13, 0x80 } \
  29   }
  30
  31 typedef struct _EFI_DHCP4_PROTOCOL EFI_DHCP4_PROTOCOL;
  32
  33
  34 #pragma pack(1)
  35 typedef struct {
  36   UINT8               OpCode;
  37   UINT8               Length;
  38   UINT8               Data[1];
  39 } EFI_DHCP4_PACKET_OPTION;
  40 #pragma pack()
  41
  42
  43 #pragma pack(1)
  44 typedef struct {
  45     UINT8             OpCode;
  46     UINT8             HwType;
  47     UINT8             HwAddrLen;
  48     UINT8             Hops;
  49     UINT32            Xid;
  50     UINT16            Seconds;
  51     UINT16            Reserved;
  52     EFI_IPv4_ADDRESS  ClientAddr;       ///< Client IP address from client
  53     EFI_IPv4_ADDRESS  YourAddr;         ///< Client IP address from server
  54     EFI_IPv4_ADDRESS  ServerAddr;       ///< IP address of next server in bootstrap
  55     EFI_IPv4_ADDRESS  GatewayAddr;      ///< Relay agent IP address
  56     UINT8             ClientHwAddr[16]; ///< Client hardware address
  57     CHAR8             ServerName[64];
  58     CHAR8             BootFileName[128];
  59 }EFI_DHCP4_HEADER;
  60 #pragma pack()
  61
  62
  63 #pragma pack(1)
  64 typedef struct {
  65   UINT32              Size;
  66   UINT32              Length;
  67
  68   struct {
  69     EFI_DHCP4_HEADER  Header;
  70     UINT32            Magik;
  71     UINT8             Option[1];
  72   } Dhcp4;
  73 } EFI_DHCP4_PACKET;
  74 #pragma pack()
  75
  76
  77 typedef enum {
  78   Dhcp4Stopped        = 0x0,
  79   Dhcp4Init           = 0x1,
  80   Dhcp4Selecting      = 0x2,
  81   Dhcp4Requesting     = 0x3,
  82   Dhcp4Bound          = 0x4,
  83   Dhcp4Renewing       = 0x5,
  84   Dhcp4Rebinding      = 0x6,
  85   Dhcp4InitReboot     = 0x7,
  86   Dhcp4Rebooting      = 0x8
  87 } EFI_DHCP4_STATE;
  88
  89
  90 typedef enum{
  91   Dhcp4SendDiscover   = 0x01,
  92   Dhcp4RcvdOffer      = 0x02,
  93   Dhcp4SelectOffer    = 0x03,
  94   Dhcp4SendRequest    = 0x04,
  95   Dhcp4RcvdAck        = 0x05,
  96   Dhcp4RcvdNak        = 0x06,
  97   Dhcp4SendDecline    = 0x07,
  98   Dhcp4BoundCompleted = 0x08,
  99   Dhcp4EnterRenewing  = 0x09,
 100   Dhcp4EnterRebinding = 0x0a,
 101   Dhcp4AddressLost    = 0x0b,
 102   Dhcp4Fail           = 0x0c
 103 } EFI_DHCP4_EVENT;
 104
 105 /**
 106   Callback routine.
 107
 108   EFI_DHCP4_CALLBACK is provided by the consumer of the EFI DHCPv4 Protocol driver
 109   to intercept events that occurred in the configuration process. This structure
 110   provides advanced control of each state transition of the DHCP process. The
 111   returned status code determines the behavior of the EFI DHCPv4 Protocol driver.
 112   There are three possible returned values, which are described in the following
 113   table.
 114
 115   @param  This                  Pointer to the EFI DHCPv4 Protocol instance that is used to
 116                                 configure this callback function.
 117   @param  Context               Pointer to the context that is initialized by
 118                                 EFI_DHCP4_PROTOCOL.Configure().
 119   @param  CurrentState          The current operational state of the EFI DHCPv4 Protocol
 120                                 driver.
 121   @param  Dhcp4Event            The event that occurs in the current state, which usually means a
 122                                 state transition.
 123   @param  Packet                The DHCP packet that is going to be sent or already received.
 124   @param  NewPacket             The packet that is used to replace the above Packet.
 125
 126   @retval EFI_SUCCESS           Tells the EFI DHCPv4 Protocol driver to continue the DHCP process.
 127   @retval EFI_NOT_READY         Only used in the Dhcp4Selecting state. The EFI DHCPv4 Protocol
 128                                 driver will continue to wait for more DHCPOFFER packets until the retry
 129                                 timeout expires.
 130   @retval EFI_ABORTED           Tells the EFI DHCPv4 Protocol driver to abort the current process and
 131                                 return to the Dhcp4Init or Dhcp4InitReboot state.
 132
 133 **/
 134 typedef
 135 EFI_STATUS
 136 (EFIAPI *EFI_DHCP4_CALLBACK)(
 137   IN  EFI_DHCP4_PROTOCOL         *This,
 138   IN  VOID                       *Context,
 139   IN  EFI_DHCP4_STATE            CurrentState,
 140   IN  EFI_DHCP4_EVENT            Dhcp4Event,
 141   IN  EFI_DHCP4_PACKET           *Packet     OPTIONAL,
 142   OUT EFI_DHCP4_PACKET           **NewPacket OPTIONAL
 143   );
 144
 145
 146 typedef struct {
 147   UINT32                      DiscoverTryCount;
 148   UINT32                      *DiscoverTimeout;
 149   UINT32                      RequestTryCount;
 150   UINT32                      *RequestTimeout;
 151   EFI_IPv4_ADDRESS            ClientAddress;
 152   EFI_DHCP4_CALLBACK          Dhcp4Callback;
 153   void                        *CallbackContext;
 154   UINT32                      OptionCount;
 155   EFI_DHCP4_PACKET_OPTION     **OptionList;
 156 } EFI_DHCP4_CONFIG_DATA;
 157
 158
 159 typedef struct {
 160   EFI_DHCP4_STATE             State;
 161   EFI_DHCP4_CONFIG_DATA       ConfigData;
 162   EFI_IPv4_ADDRESS            ClientAddress;
 163   EFI_MAC_ADDRESS             ClientMacAddress;
 164   EFI_IPv4_ADDRESS            ServerAddress;
 165   EFI_IPv4_ADDRESS            RouterAddress;
 166   EFI_IPv4_ADDRESS            SubnetMask;
 167   UINT32                      LeaseTime;
 168   EFI_DHCP4_PACKET            *ReplyPacket;
 169 } EFI_DHCP4_MODE_DATA;
 170
 171
 172 typedef struct {
 173   EFI_IPv4_ADDRESS            ListenAddress;
 174   EFI_IPv4_ADDRESS            SubnetMask;
 175   UINT16                      ListenPort;
 176 } EFI_DHCP4_LISTEN_POINT;
 177
 178
 179 typedef struct {
 180   EFI_STATUS              Status;
 181   EFI_EVENT               CompletionEvent;
 182   EFI_IPv4_ADDRESS        RemoteAddress;
 183   UINT16                  RemotePort;
 184   EFI_IPv4_ADDRESS        GatewayAddress;
 185   UINT32                  ListenPointCount;
 186   EFI_DHCP4_LISTEN_POINT  *ListenPoints;
 187   UINT32                  TimeoutValue;
 188   EFI_DHCP4_PACKET        *Packet;
 189   UINT32                  ResponseCount;
 190   EFI_DHCP4_PACKET        *ResponseList;
 191 } EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN;
 192
 193
 194 /**
 195   Returns the current operating mode and cached data packet for the EFI DHCPv4 Protocol driver.
 196
 197   The GetModeData() function returns the current operating mode and cached data
 198   packet for the EFI DHCPv4 Protocol driver.
 199
 200   @param  This          Pointer to the EFI_DHCP4_PROTOCOL instance.
 201   @param  Dhcp4ModeData Pointer to storage for the EFI_DHCP4_MODE_DATA structure.
 202
 203   @retval EFI_SUCCESS           The mode data was returned.
 204   @retval EFI_INVALID_PARAMETER This is NULL.
 205
 206 **/
 207 typedef
 208 EFI_STATUS
 209 (EFIAPI *EFI_DHCP4_GET_MODE_DATA)(
 210   IN  EFI_DHCP4_PROTOCOL      *This,
 211   OUT EFI_DHCP4_MODE_DATA     *Dhcp4ModeData
 212   );
 213
 214 /**
 215   Initializes, changes, or resets the operational settings for the EFI DHCPv4 Protocol driver.
 216
 217   The Configure() function is used to initialize, change, or reset the operational
 218   settings of the EFI DHCPv4 Protocol driver for the communication device on which
 219   the EFI DHCPv4 Service Binding Protocol is installed. This function can be
 220   successfully called only if both of the following are true:
 221   * This instance of the EFI DHCPv4 Protocol driver is in the Dhcp4Stopped, Dhcp4Init,
 222     Dhcp4InitReboot, or Dhcp4Bound states.
 223   * No other EFI DHCPv4 Protocol driver instance that is controlled by this EFI
 224     DHCPv4 Service Binding Protocol driver instance has configured this EFI DHCPv4
 225     Protocol driver.
 226   When this driver is in the Dhcp4Stopped state, it can transfer into one of the
 227   following two possible initial states:
 228   * Dhcp4Init
 229   * Dhcp4InitReboot
 230   The driver can transfer into these states by calling Configure() with a non-NULL
 231   Dhcp4CfgData. The driver will transfer into the appropriate state based on the
 232   supplied client network address in the ClientAddress parameter and DHCP options
 233   in the OptionList parameter as described in RFC 2131.
 234   When Configure() is called successfully while Dhcp4CfgData is set to NULL, the
 235   default configuring data will be reset in the EFI DHCPv4 Protocol driver and
 236   the state of the EFI DHCPv4 Protocol driver will not be changed. If one instance
 237   wants to make it possible for another instance to configure the EFI DHCPv4 Protocol
 238   driver, it must call this function with Dhcp4CfgData set to NULL.
 239
 240   @param  This                   Pointer to the EFI_DHCP4_PROTOCOL instance.
 241   @param  Dhcp4CfgData           Pointer to the EFI_DHCP4_CONFIG_DATA.
 242
 243   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Init or
 244                                 Dhcp4InitReboot state, if the original state of this driver
 245                                 was Dhcp4Stopped and the value of Dhcp4CfgData was
 246                                 not NULL. Otherwise, the state was left unchanged.
 247   @retval EFI_ACCESS_DENIED     This instance of the EFI DHCPv4 Protocol driver was not in the
 248                                 Dhcp4Stopped, Dhcp4Init, Dhcp4InitReboot, or Dhcp4Bound state;
 249                                 Or onother instance of this EFI DHCPv4 Protocol driver is already
 250                                 in a valid configured state.
 251   @retval EFI_INVALID_PARAMETER Some parameter is NULL.
 252   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 253   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 254
 255 **/
 256 typedef
 257 EFI_STATUS
 258 (EFIAPI *EFI_DHCP4_CONFIGURE)(
 259   IN EFI_DHCP4_PROTOCOL       *This,
 260   IN EFI_DHCP4_CONFIG_DATA    *Dhcp4CfgData  OPTIONAL
 261   );
 262
 263
 264 /**
 265   Starts the DHCP configuration process.
 266
 267   The Start() function starts the DHCP configuration process. This function can
 268   be called only when the EFI DHCPv4 Protocol driver is in the Dhcp4Init or
 269   Dhcp4InitReboot state.
 270   If the DHCP process completes successfully, the state of the EFI DHCPv4 Protocol
 271   driver will be transferred through Dhcp4Selecting and Dhcp4Requesting to the
 272   Dhcp4Bound state. The CompletionEvent will then be signaled if it is not NULL.
 273   If the process aborts, either by the user or by some unexpected network error,
 274   the state is restored to the Dhcp4Init state. The Start() function can be called
 275   again to restart the process.
 276   Refer to RFC 2131 for precise state transitions during this process. At the
 277   time when each event occurs in this process, the callback function that was set
 278   by EFI_DHCP4_PROTOCOL.Configure() will be called and the user can take this
 279   opportunity to control the process.
 280
 281   @param  This            Pointer to the EFI_DHCP4_PROTOCOL instance.
 282   @param  CompletionEvent If not NULL, indicates the event that will be signaled when the
 283                           EFI DHCPv4 Protocol driver is transferred into the
 284                           Dhcp4Bound state or when the DHCP process is aborted.
 285                           EFI_DHCP4_PROTOCOL.GetModeData() can be called to
 286                           check the completion status. If NULL,
 287                           EFI_DHCP4_PROTOCOL.Start() will wait until the driver
 288                           is transferred into the Dhcp4Bound state or the process fails.
 289
 290   @retval EFI_SUCCESS           The DHCP configuration process has started, or it has completed
 291                                 when CompletionEvent is NULL.
 292   @retval EFI_NOT_STARTED       The EFI DHCPv4 Protocol driver is in the Dhcp4Stopped
 293                                 state. EFI_DHCP4_PROTOCOL. Configure() needs to be called.
 294   @retval EFI_INVALID_PARAMETER This is NULL.
 295   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 296   @retval EFI_TIMEOUT           The DHCP configuration process failed because no response was
 297                                 received from the server within the specified timeout value.
 298   @retval EFI_ABORTED           The user aborted the DHCP process.
 299   @retval EFI_ALREADY_STARTED   Some other EFI DHCPv4 Protocol instance already started the
 300                                 DHCP process.
 301   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 302
 303 **/
 304 typedef
 305 EFI_STATUS
 306 (EFIAPI *EFI_DHCP4_START)(
 307   IN EFI_DHCP4_PROTOCOL       *This,
 308   IN EFI_EVENT                CompletionEvent   OPTIONAL
 309   );
 310
 311 /**
 312   Extends the lease time by sending a request packet.
 313
 314   The RenewRebind() function is used to manually extend the lease time when the
 315   EFI DHCPv4 Protocol driver is in the Dhcp4Bound state and the lease time has
 316   not expired yet. This function will send a request packet to the previously
 317   found server (or to any server when RebindRequest is TRUE) and transfer the
 318   state into the Dhcp4Renewing state (or Dhcp4Rebinding when RebindingRequest is
 319   TRUE). When a response is received, the state is returned to Dhcp4Bound.
 320   If no response is received before the try count is exceeded (the RequestTryCount
 321   field that is specified in EFI_DHCP4_CONFIG_DATA) but before the lease time that
 322   was issued by the previous server expires, the driver will return to the Dhcp4Bound
 323   state and the previous configuration is restored. The outgoing and incoming packets
 324   can be captured by the EFI_DHCP4_CALLBACK function.
 325
 326   @param  This            Pointer to the EFI_DHCP4_PROTOCOL instance.
 327   @param  RebindRequest   If TRUE, this function broadcasts the request packets and enters
 328                           the Dhcp4Rebinding state. Otherwise, it sends a unicast
 329                           request packet and enters the Dhcp4Renewing state.
 330   @param  CompletionEvent If not NULL, this event is signaled when the renew/rebind phase
 331                           completes or some error occurs.
 332                           EFI_DHCP4_PROTOCOL.GetModeData() can be called to
 333                           check the completion status. If NULL,
 334                           EFI_DHCP4_PROTOCOL.RenewRebind() will busy-wait
 335                           until the DHCP process finishes.
 336
 337   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the
 338                                 Dhcp4Renewing state or is back to the Dhcp4Bound state.
 339   @retval EFI_NOT_STARTED       The EFI DHCPv4 Protocol driver is in the Dhcp4Stopped
 340                                 state. EFI_DHCP4_PROTOCOL.Configure() needs to
 341                                 be called.
 342   @retval EFI_INVALID_PARAMETER This is NULL.
 343   @retval EFI_TIMEOUT           There was no response from the server when the try count was
 344                                 exceeded.
 345   @retval EFI_ACCESS_DENIED     The driver is not in the Dhcp4Bound state.
 346   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 347
 348 **/
 349 typedef
 350 EFI_STATUS
 351 (EFIAPI *EFI_DHCP4_RENEW_REBIND)(
 352   IN EFI_DHCP4_PROTOCOL       *This,
 353   IN BOOLEAN                  RebindRequest,
 354   IN EFI_EVENT                CompletionEvent  OPTIONAL
 355   );
 356
 357 /**
 358   Releases the current address configuration.
 359
 360   The Release() function releases the current configured IP address by doing either
 361   of the following:
 362   * Sending a DHCPRELEASE packet when the EFI DHCPv4 Protocol driver is in the
 363     Dhcp4Bound state
 364   * Setting the previously assigned IP address that was provided with the
 365     EFI_DHCP4_PROTOCOL.Configure() function to 0.0.0.0 when the driver is in
 366     Dhcp4InitReboot state
 367   After a successful call to this function, the EFI DHCPv4 Protocol driver returns
 368   to the Dhcp4Init state and any subsequent incoming packets will be discarded silently.
 369
 370   @param  This                  Pointer to the EFI_DHCP4_PROTOCOL instance.
 371
 372   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Init phase.
 373   @retval EFI_INVALID_PARAMETER This is NULL.
 374   @retval EFI_ACCESS_DENIED     The EFI DHCPv4 Protocol driver is not Dhcp4InitReboot state.
 375   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 376
 377 **/
 378 typedef
 379 EFI_STATUS
 380 (EFIAPI *EFI_DHCP4_RELEASE)(
 381   IN EFI_DHCP4_PROTOCOL       *This
 382   );
 383
 384 /**
 385   Stops the current address configuration.
 386
 387   The Stop() function is used to stop the DHCP configuration process. After this
 388   function is called successfully, the EFI DHCPv4 Protocol driver is transferred
 389   into the Dhcp4Stopped state. EFI_DHCP4_PROTOCOL.Configure() needs to be called
 390   before DHCP configuration process can be started again. This function can be
 391   called when the EFI DHCPv4 Protocol driver is in any state.
 392
 393   @param  This                  Pointer to the EFI_DHCP4_PROTOCOL instance.
 394
 395   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Stopped phase.
 396   @retval EFI_INVALID_PARAMETER This is NULL.
 397
 398 **/
 399 typedef
 400 EFI_STATUS
 401 (EFIAPI *EFI_DHCP4_STOP)(
 402   IN EFI_DHCP4_PROTOCOL       *This
 403   );
 404
 405 /**
 406   Builds a DHCP packet, given the options to be appended or deleted or replaced.
 407
 408   The Build() function is used to assemble a new packet from the original packet
 409   by replacing or deleting existing options or appending new options. This function
 410   does not change any state of the EFI DHCPv4 Protocol driver and can be used at
 411   any time.
 412
 413   @param  This        Pointer to the EFI_DHCP4_PROTOCOL instance.
 414   @param  SeedPacket  Initial packet to be used as a base for building new packet.
 415   @param  DeleteCount Number of opcodes in the DeleteList.
 416   @param  DeleteList  List of opcodes to be deleted from the seed packet.
 417                       Ignored if DeleteCount is zero.
 418   @param  AppendCount Number of entries in the OptionList.
 419   @param  AppendList  Pointer to a DHCP option list to be appended to SeedPacket.
 420                       If SeedPacket also contains options in this list, they are
 421                       replaced by new options (except pad option). Ignored if
 422                       AppendCount is zero. Type EFI_DHCP4_PACKET_OPTION
 423   @param  NewPacket   Pointer to storage for the pointer to the new allocated packet.
 424                       Use the EFI Boot Service FreePool() on the resulting pointer
 425                       when done with the packet.
 426
 427   @retval EFI_SUCCESS           The new packet was built.
 428   @retval EFI_OUT_OF_RESOURCES  Storage for the new packet could not be allocated.
 429   @retval EFI_INVALID_PARAMETER Some parameter is NULL.
 430
 431 **/
 432 typedef
 433 EFI_STATUS
 434 (EFIAPI *EFI_DHCP4_BUILD)(
 435   IN  EFI_DHCP4_PROTOCOL      *This,
 436   IN  EFI_DHCP4_PACKET        *SeedPacket,
 437   IN  UINT32                  DeleteCount,
 438   IN  UINT8                   *DeleteList         OPTIONAL,
 439   IN  UINT32                  AppendCount,
 440   IN  EFI_DHCP4_PACKET_OPTION *AppendList[]       OPTIONAL,
 441   OUT EFI_DHCP4_PACKET        **NewPacket
 442   );
 443
 444
 445 /**
 446   Transmits a DHCP formatted packet and optionally waits for responses.
 447
 448   The TransmitReceive() function is used to transmit a DHCP packet and optionally
 449   wait for the response from servers. This function does not change the state of
 450   the EFI DHCPv4 Protocol driver and thus can be used at any time.
 451
 452   @param  This    Pointer to the EFI_DHCP4_PROTOCOL instance.
 453   @param  Token   Pointer to the EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN structure.
 454
 455   @retval EFI_SUCCESS           The packet was successfully queued for transmission.
 456   @retval EFI_INVALID_PARAMETER Some parameter is NULL.
 457   @retval EFI_NOT_READY         The previous call to this function has not finished yet. Try to call
 458                                 this function after collection process completes.
 459   @retval EFI_NO_MAPPING        The default station address is not available yet.
 460   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 461   @retval Others                Some other unexpected error occurred.
 462
 463 **/
 464 typedef
 465 EFI_STATUS
 466 (EFIAPI *EFI_DHCP4_TRANSMIT_RECEIVE)(
 467   IN EFI_DHCP4_PROTOCOL                *This,
 468   IN EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN  *Token
 469   );
 470
 471
 472 /**
 473   Parses the packed DHCP option data.
 474
 475   The Parse() function is used to retrieve the option list from a DHCP packet.
 476   If *OptionCount isn’t zero, and there is enough space for all the DHCP options
 477   in the Packet, each element of PacketOptionList is set to point to somewhere in
 478   the Packet->Dhcp4.Option where a new DHCP option begins. If RFC3396 is supported,
 479   the caller should reassemble the parsed DHCP options to get the finial result.
 480   If *OptionCount is zero or there isn’t enough space for all of them, the number
 481   of DHCP options in the Packet is returned in OptionCount.
 482
 483   @param  This             Pointer to the EFI_DHCP4_PROTOCOL instance.
 484   @param  Packet           Pointer to packet to be parsed.
 485   @param  OptionCount      On input, the number of entries in the PacketOptionList.
 486                            On output, the number of entries that were written into the
 487                            PacketOptionList.
 488   @param  PacketOptionList List of packet option entries to be filled in. End option or pad
 489                            options are not included.
 490
 491   @retval EFI_SUCCESS           The packet was successfully parsed.
 492   @retval EFI_INVALID_PARAMETER Some parameter is NULL.
 493   @retval EFI_BUFFER_TOO_SMALL  One or more of the following conditions is TRUE:
 494                                 1) *OptionCount is smaller than the number of options that
 495                                 were found in the Packet.
 496                                 2) PacketOptionList is NULL.
 497
 498 **/
 499 typedef
 500 EFI_STATUS
 501 (EFIAPI *EFI_DHCP4_PARSE)(
 502   IN EFI_DHCP4_PROTOCOL        *This,
 503   IN EFI_DHCP4_PACKET          *Packet,
 504   IN OUT UINT32                *OptionCount,
 505   OUT EFI_DHCP4_PACKET_OPTION  *PacketOptionList[]  OPTIONAL
 506   );
 507
 508 ///
 509 /// This protocol is used to collect configuration information for the EFI IPv4 Protocol drivers
 510 /// and to provide DHCPv4 server and PXE boot server discovery services.
 511 ///
 512 struct _EFI_DHCP4_PROTOCOL {
 513   EFI_DHCP4_GET_MODE_DATA      GetModeData;
 514   EFI_DHCP4_CONFIGURE          Configure;
 515   EFI_DHCP4_START              Start;
 516   EFI_DHCP4_RENEW_REBIND       RenewRebind;
 517   EFI_DHCP4_RELEASE            Release;
 518   EFI_DHCP4_STOP               Stop;
 519   EFI_DHCP4_BUILD              Build;
 520   EFI_DHCP4_TRANSMIT_RECEIVE   TransmitReceive;
 521   EFI_DHCP4_PARSE              Parse;
 522 };
 523
 524 extern EFI_GUID gEfiDhcp4ProtocolGuid;
 525 extern EFI_GUID gEfiDhcp4ServiceBindingProtocolGuid;
 526
 527 #endif