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 - 2018, Intel Corporation. All rights reserved.<BR>
   8 SPDX-License-Identifier: BSD-2-Clause-Patent
   9
  10   @par Revision Reference:
  11   This Protocol was introduced in UEFI Specification 2.0.
  12
  13 **/
  14
  15 #ifndef __EFI_DHCP4_PROTOCOL_H__
  16 #define __EFI_DHCP4_PROTOCOL_H__
  17
  18 #define EFI_DHCP4_PROTOCOL_GUID \
  19   { \
  20     0x8a219718, 0x4ef5, 0x4761, {0x91, 0xc8, 0xc0, 0xf0, 0x4b, 0xda, 0x9e, 0x56 } \
  21   }
  22
  23 #define EFI_DHCP4_SERVICE_BINDING_PROTOCOL_GUID \
  24   { \
  25     0x9d9a39d8, 0xbd42, 0x4a73, {0xa4, 0xd5, 0x8e, 0xe9, 0x4b, 0xe1, 0x13, 0x80 } \
  26   }
  27
  28 typedef struct _EFI_DHCP4_PROTOCOL EFI_DHCP4_PROTOCOL;
  29
  30
  31 #pragma pack(1)
  32 typedef struct {
  33   ///
  34   /// DHCP option code.
  35   ///
  36   UINT8               OpCode;
  37   ///
  38   /// Length of the DHCP option data. Not present if OpCode is 0 or 255.
  39   ///
  40   UINT8               Length;
  41   ///
  42   /// Start of the DHCP option data. Not present if OpCode is 0 or 255 or if Length is zero.
  43   ///
  44   UINT8               Data[1];
  45 } EFI_DHCP4_PACKET_OPTION;
  46 #pragma pack()
  47
  48
  49 #pragma pack(1)
  50 ///
  51 /// EFI_DHCP4_PACKET defines the format of DHCPv4 packets. See RFC 2131 for more information.
  52 ///
  53 typedef struct {
  54   UINT8             OpCode;
  55   UINT8             HwType;
  56   UINT8             HwAddrLen;
  57   UINT8             Hops;
  58   UINT32            Xid;
  59   UINT16            Seconds;
  60   UINT16            Reserved;
  61   EFI_IPv4_ADDRESS  ClientAddr;       ///< Client IP address from client.
  62   EFI_IPv4_ADDRESS  YourAddr;         ///< Client IP address from server.
  63   EFI_IPv4_ADDRESS  ServerAddr;       ///< IP address of next server in bootstrap.
  64   EFI_IPv4_ADDRESS  GatewayAddr;      ///< Relay agent IP address.
  65   UINT8             ClientHwAddr[16]; ///< Client hardware address.
  66   CHAR8             ServerName[64];
  67   CHAR8             BootFileName[128];
  68 }EFI_DHCP4_HEADER;
  69 #pragma pack()
  70
  71
  72 #pragma pack(1)
  73 typedef struct {
  74   ///
  75   /// Size of the EFI_DHCP4_PACKET buffer.
  76   ///
  77   UINT32              Size;
  78   ///
  79   /// Length of the EFI_DHCP4_PACKET from the first byte of the Header field
  80   /// to the last byte of the Option[] field.
  81   ///
  82   UINT32              Length;
  83
  84   struct {
  85     ///
  86     /// DHCP packet header.
  87     ///
  88     EFI_DHCP4_HEADER  Header;
  89     ///
  90     /// DHCP magik cookie in network byte order.
  91     ///
  92     UINT32            Magik;
  93     ///
  94     /// Start of the DHCP packed option data.
  95     ///
  96     UINT8             Option[1];
  97   } Dhcp4;
  98 } EFI_DHCP4_PACKET;
  99 #pragma pack()
 100
 101
 102 typedef enum {
 103   ///
 104   /// The EFI DHCPv4 Protocol driver is stopped.
 105   ///
 106   Dhcp4Stopped        = 0x0,
 107   ///
 108   /// The EFI DHCPv4 Protocol driver is inactive.
 109   ///
 110   Dhcp4Init           = 0x1,
 111   ///
 112   /// The EFI DHCPv4 Protocol driver is collecting DHCP offer packets from DHCP servers.
 113   ///
 114   Dhcp4Selecting      = 0x2,
 115   ///
 116   /// The EFI DHCPv4 Protocol driver has sent the request to the DHCP server and is waiting for a response.
 117   ///
 118   Dhcp4Requesting     = 0x3,
 119   ///
 120   /// The DHCP configuration has completed.
 121   ///
 122   Dhcp4Bound          = 0x4,
 123   ///
 124   /// The DHCP configuration is being renewed and another request has
 125   /// been sent out, but it has not received a response from the server yet.
 126   ///
 127   Dhcp4Renewing       = 0x5,
 128   ///
 129   /// The DHCP configuration has timed out and the EFI DHCPv4
 130   /// Protocol driver is trying to extend the lease time.
 131   ///
 132   Dhcp4Rebinding      = 0x6,
 133   ///
 134   /// The EFI DHCPv4 Protocol driver was initialized with a previously
 135   /// allocated or known IP address.
 136   ///
 137   Dhcp4InitReboot     = 0x7,
 138   ///
 139   /// The EFI DHCPv4 Protocol driver is seeking to reuse the previously
 140   /// allocated IP address by sending a request to the DHCP server.
 141   ///
 142   Dhcp4Rebooting      = 0x8
 143 } EFI_DHCP4_STATE;
 144
 145
 146 typedef enum{
 147   ///
 148   /// The packet to start the configuration sequence is about to be sent.
 149   ///
 150   Dhcp4SendDiscover   = 0x01,
 151   ///
 152   /// A reply packet was just received.
 153   ///
 154   Dhcp4RcvdOffer      = 0x02,
 155   ///
 156   /// It is time for Dhcp4Callback to select an offer.
 157   ///
 158   Dhcp4SelectOffer    = 0x03,
 159   ///
 160   /// A request packet is about to be sent.
 161   ///
 162   Dhcp4SendRequest    = 0x04,
 163   ///
 164   /// A DHCPACK packet was received and will be passed to Dhcp4Callback.
 165   ///
 166   Dhcp4RcvdAck        = 0x05,
 167   ///
 168   /// A DHCPNAK packet was received and will be passed to Dhcp4Callback.
 169   ///
 170   Dhcp4RcvdNak        = 0x06,
 171   ///
 172   /// A decline packet is about to be sent.
 173   ///
 174   Dhcp4SendDecline    = 0x07,
 175   ///
 176   /// The DHCP configuration process has completed. No packet is associated with this event.
 177   ///
 178   Dhcp4BoundCompleted = 0x08,
 179   ///
 180   /// It is time to enter the Dhcp4Renewing state and to contact the server
 181   /// that originally issued the network address. No packet is associated with this event.
 182   ///
 183   Dhcp4EnterRenewing  = 0x09,
 184   ///
 185   /// It is time to enter the Dhcp4Rebinding state and to contact any server.
 186   /// No packet is associated with this event.
 187   ///
 188   Dhcp4EnterRebinding = 0x0a,
 189   ///
 190   /// The configured IP address was lost either because the lease has expired,
 191   /// the user released the configuration, or a DHCPNAK packet was received in
 192   /// the Dhcp4Renewing or Dhcp4Rebinding state. No packet is associated with this event.
 193   ///
 194   Dhcp4AddressLost    = 0x0b,
 195   ///
 196   /// The DHCP process failed because a DHCPNAK packet was received or the user
 197   /// aborted the DHCP process at a time when the configuration was not available yet.
 198   /// No packet is associated with this event.
 199   ///
 200   Dhcp4Fail           = 0x0c
 201 } EFI_DHCP4_EVENT;
 202
 203 /**
 204   Callback routine.
 205
 206   EFI_DHCP4_CALLBACK is provided by the consumer of the EFI DHCPv4 Protocol driver
 207   to intercept events that occurred in the configuration process. This structure
 208   provides advanced control of each state transition of the DHCP process. The
 209   returned status code determines the behavior of the EFI DHCPv4 Protocol driver.
 210   There are three possible returned values, which are described in the following
 211   table.
 212
 213   @param  This                  The pointer to the EFI DHCPv4 Protocol instance that is used to
 214                                 configure this callback function.
 215   @param  Context               The pointer to the context that is initialized by
 216                                 EFI_DHCP4_PROTOCOL.Configure().
 217   @param  CurrentState          The current operational state of the EFI DHCPv4 Protocol
 218                                 driver.
 219   @param  Dhcp4Event            The event that occurs in the current state, which usually means a
 220                                 state transition.
 221   @param  Packet                The DHCP packet that is going to be sent or already received.
 222   @param  NewPacket             The packet that is used to replace the above Packet.
 223
 224   @retval EFI_SUCCESS           Tells the EFI DHCPv4 Protocol driver to continue the DHCP process.
 225                                 When it is in the Dhcp4Selecting state, it tells the EFI DHCPv4 Protocol
 226                                 driver to stop collecting additional packets. The driver will exit
 227                                 the Dhcp4Selecting state and enter the Dhcp4Requesting state.
 228   @retval EFI_NOT_READY         Only used in the Dhcp4Selecting state. The EFI DHCPv4 Protocol
 229                                 driver will continue to wait for more packets until the retry
 230                                 timeout expires.
 231   @retval EFI_ABORTED           Tells the EFI DHCPv4 Protocol driver to abort the current process and
 232                                 return to the Dhcp4Init or Dhcp4InitReboot state.
 233
 234 **/
 235 typedef
 236 EFI_STATUS
 237 (EFIAPI *EFI_DHCP4_CALLBACK)(
 238   IN  EFI_DHCP4_PROTOCOL         *This,
 239   IN  VOID                       *Context,
 240   IN  EFI_DHCP4_STATE            CurrentState,
 241   IN  EFI_DHCP4_EVENT            Dhcp4Event,
 242   IN  EFI_DHCP4_PACKET           *Packet     OPTIONAL,
 243   OUT EFI_DHCP4_PACKET           **NewPacket OPTIONAL
 244   );
 245
 246 typedef struct {
 247   ///
 248   /// The number of times to try sending a packet during the Dhcp4SendDiscover
 249   /// event and waiting for a response during the Dhcp4RcvdOffer event.
 250   /// Set to zero to use the default try counts and timeout values.
 251   ///
 252   UINT32                      DiscoverTryCount;
 253   ///
 254   /// The maximum amount of time (in seconds) to wait for returned packets in each
 255   /// of the retries. Timeout values of zero will default to a timeout value
 256   /// of one second. Set to NULL to use default timeout values.
 257   ///
 258   UINT32                      *DiscoverTimeout;
 259   ///
 260   /// The number of times to try sending a packet during the Dhcp4SendRequest event
 261   /// and waiting for a response during the Dhcp4RcvdAck event before accepting
 262   /// failure. Set to zero to use the default try counts and timeout values.
 263   ///
 264   UINT32                      RequestTryCount;
 265   ///
 266   /// The maximum amount of time (in seconds) to wait for return packets in each of the retries.
 267   /// Timeout values of zero will default to a timeout value of one second.
 268   /// Set to NULL to use default timeout values.
 269   ///
 270   UINT32                      *RequestTimeout;
 271   ///
 272   /// For a DHCPDISCOVER, setting this parameter to the previously allocated IP
 273   /// address will cause the EFI DHCPv4 Protocol driver to enter the Dhcp4InitReboot state.
 274   /// And set this field to 0.0.0.0 to enter the Dhcp4Init state.
 275   /// For a DHCPINFORM this parameter should be set to the client network address
 276   /// which was assigned to the client during a DHCPDISCOVER.
 277   ///
 278   EFI_IPv4_ADDRESS            ClientAddress;
 279   ///
 280   /// The callback function to intercept various events that occurred in
 281   /// the DHCP configuration process. Set to NULL to ignore all those events.
 282   ///
 283   EFI_DHCP4_CALLBACK          Dhcp4Callback;
 284   ///
 285   /// The pointer to the context that will be passed to Dhcp4Callback when it is called.
 286   ///
 287   VOID                        *CallbackContext;
 288   ///
 289   /// Number of DHCP options in the OptionList.
 290   ///
 291   UINT32                      OptionCount;
 292   ///
 293   /// List of DHCP options to be included in every packet that is sent during the
 294   /// Dhcp4SendDiscover event. Pad options are appended automatically by DHCP driver
 295   /// in outgoing DHCP packets. If OptionList itself contains pad option, they are
 296   /// ignored by the driver. OptionList can be freed after EFI_DHCP4_PROTOCOL.Configure()
 297   /// returns. Ignored if OptionCount is zero.
 298   ///
 299   EFI_DHCP4_PACKET_OPTION     **OptionList;
 300 } EFI_DHCP4_CONFIG_DATA;
 301
 302
 303 typedef struct {
 304   ///
 305   /// The EFI DHCPv4 Protocol driver operating state.
 306   ///
 307   EFI_DHCP4_STATE             State;
 308   ///
 309   /// The configuration data of the current EFI DHCPv4 Protocol driver instance.
 310   ///
 311   EFI_DHCP4_CONFIG_DATA       ConfigData;
 312   ///
 313   /// The client IP address that was acquired from the DHCP server. If it is zero,
 314   /// the DHCP acquisition has not completed yet and the following fields in this structure are undefined.
 315   ///
 316   EFI_IPv4_ADDRESS            ClientAddress;
 317   ///
 318   /// The local hardware address.
 319   ///
 320   EFI_MAC_ADDRESS             ClientMacAddress;
 321   ///
 322   /// The server IP address that is providing the DHCP service to this client.
 323   ///
 324   EFI_IPv4_ADDRESS            ServerAddress;
 325   ///
 326   /// The router IP address that was acquired from the DHCP server.
 327   /// May be zero if the server does not offer this address.
 328   ///
 329   EFI_IPv4_ADDRESS            RouterAddress;
 330   ///
 331   /// The subnet mask of the connected network that was acquired from the DHCP server.
 332   ///
 333   EFI_IPv4_ADDRESS            SubnetMask;
 334   ///
 335   /// The lease time (in 1-second units) of the configured IP address.
 336   /// The value 0xFFFFFFFF means that the lease time is infinite.
 337   /// A default lease of 7 days is used if the DHCP server does not provide a value.
 338   ///
 339   UINT32                      LeaseTime;
 340   ///
 341   /// The cached latest DHCPACK or DHCPNAK or BOOTP REPLY packet. May be NULL if no packet is cached.
 342   ///
 343   EFI_DHCP4_PACKET            *ReplyPacket;
 344 } EFI_DHCP4_MODE_DATA;
 345
 346
 347 typedef struct {
 348   ///
 349   /// Alternate listening address. It can be a unicast, multicast, or broadcast address.
 350   ///
 351   EFI_IPv4_ADDRESS            ListenAddress;
 352   ///
 353   /// The subnet mask of above listening unicast/broadcast IP address.
 354   /// Ignored if ListenAddress is a multicast address.
 355   ///
 356   EFI_IPv4_ADDRESS            SubnetMask;
 357   ///
 358   /// Alternate station source (or listening) port number.
 359   /// If zero, then the default station port number (68) will be used.
 360   ///
 361   UINT16                      ListenPort;
 362 } EFI_DHCP4_LISTEN_POINT;
 363
 364
 365 typedef struct {
 366   ///
 367   /// The completion status of transmitting and receiving.
 368   ///
 369   EFI_STATUS              Status;
 370   ///
 371   /// If not NULL, the event that will be signaled when the collection process
 372   /// completes. If NULL, this function will busy-wait until the collection process competes.
 373   ///
 374   EFI_EVENT               CompletionEvent;
 375   ///
 376   /// The pointer to the server IP address. This address may be a unicast, multicast, or broadcast address.
 377   ///
 378   EFI_IPv4_ADDRESS        RemoteAddress;
 379   ///
 380   /// The server listening port number. If zero, the default server listening port number (67) will be used.
 381   ///
 382   UINT16                  RemotePort;
 383   ///
 384   /// The pointer to the gateway address to override the existing setting.
 385   ///
 386   EFI_IPv4_ADDRESS        GatewayAddress;
 387   ///
 388   /// The number of entries in ListenPoints. If zero, the default station address and port number 68 are used.
 389   ///
 390   UINT32                  ListenPointCount;
 391   ///
 392   /// An array of station address and port number pairs that are used as receiving filters.
 393   /// The first entry is also used as the source address and source port of the outgoing packet.
 394   ///
 395   EFI_DHCP4_LISTEN_POINT  *ListenPoints;
 396   ///
 397   /// The number of seconds to collect responses. Zero is invalid.
 398   ///
 399   UINT32                  TimeoutValue;
 400   ///
 401   /// The pointer to the packet to be transmitted.
 402   ///
 403   EFI_DHCP4_PACKET        *Packet;
 404   ///
 405   /// Number of received packets.
 406   ///
 407   UINT32                  ResponseCount;
 408   ///
 409   /// The pointer to the allocated list of received packets.
 410   ///
 411   EFI_DHCP4_PACKET        *ResponseList;
 412 } EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN;
 413
 414
 415 /**
 416   Returns the current operating mode and cached data packet for the EFI DHCPv4 Protocol driver.
 417
 418   The GetModeData() function returns the current operating mode and cached data
 419   packet for the EFI DHCPv4 Protocol driver.
 420
 421   @param  This          The pointer to the EFI_DHCP4_PROTOCOL instance.
 422   @param  Dhcp4ModeData The pointer to storage for the EFI_DHCP4_MODE_DATA structure.
 423
 424   @retval EFI_SUCCESS           The mode data was returned.
 425   @retval EFI_INVALID_PARAMETER This is NULL.
 426
 427 **/
 428 typedef
 429 EFI_STATUS
 430 (EFIAPI *EFI_DHCP4_GET_MODE_DATA)(
 431   IN  EFI_DHCP4_PROTOCOL      *This,
 432   OUT EFI_DHCP4_MODE_DATA     *Dhcp4ModeData
 433   );
 434
 435 /**
 436   Initializes, changes, or resets the operational settings for the EFI DHCPv4 Protocol driver.
 437
 438   The Configure() function is used to initialize, change, or reset the operational
 439   settings of the EFI DHCPv4 Protocol driver for the communication device on which
 440   the EFI DHCPv4 Service Binding Protocol is installed. This function can be
 441   successfully called only if both of the following are true:
 442   * This instance of the EFI DHCPv4 Protocol driver is in the Dhcp4Stopped, Dhcp4Init,
 443     Dhcp4InitReboot, or Dhcp4Bound states.
 444   * No other EFI DHCPv4 Protocol driver instance that is controlled by this EFI
 445     DHCPv4 Service Binding Protocol driver instance has configured this EFI DHCPv4
 446     Protocol driver.
 447   When this driver is in the Dhcp4Stopped state, it can transfer into one of the
 448   following two possible initial states:
 449   * Dhcp4Init
 450   * Dhcp4InitReboot.
 451   The driver can transfer into these states by calling Configure() with a non-NULL
 452   Dhcp4CfgData. The driver will transfer into the appropriate state based on the
 453   supplied client network address in the ClientAddress parameter and DHCP options
 454   in the OptionList parameter as described in RFC 2131.
 455   When Configure() is called successfully while Dhcp4CfgData is set to NULL, the
 456   default configuring data will be reset in the EFI DHCPv4 Protocol driver and
 457   the state of the EFI DHCPv4 Protocol driver will not be changed. If one instance
 458   wants to make it possible for another instance to configure the EFI DHCPv4 Protocol
 459   driver, it must call this function with Dhcp4CfgData set to NULL.
 460
 461   @param  This                   The pointer to the EFI_DHCP4_PROTOCOL instance.
 462   @param  Dhcp4CfgData           The pointer to the EFI_DHCP4_CONFIG_DATA.
 463
 464   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Init or
 465                                 Dhcp4InitReboot state, if the original state of this driver
 466                                 was Dhcp4Stopped, Dhcp4Init,Dhcp4InitReboot, or Dhcp4Bound
 467                                 and the value of Dhcp4CfgData was not NULL.
 468                                 Otherwise, the state was left unchanged.
 469   @retval EFI_ACCESS_DENIED     This instance of the EFI DHCPv4 Protocol driver was not in the
 470                                 Dhcp4Stopped, Dhcp4Init, Dhcp4InitReboot, or Dhcp4Bound state;
 471                                 Or onother instance of this EFI DHCPv4 Protocol driver is already
 472                                 in a valid configured state.
 473   @retval EFI_INVALID_PARAMETER One or more following conditions are TRUE:
 474                                 This is NULL.
 475                                 DiscoverTryCount > 0 and DiscoverTimeout is NULL
 476                                 RequestTryCount > 0 and RequestTimeout is NULL.
 477                                 OptionCount >0 and OptionList is NULL.
 478                                 ClientAddress is not a valid unicast address.
 479   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 480   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 481
 482 **/
 483 typedef
 484 EFI_STATUS
 485 (EFIAPI *EFI_DHCP4_CONFIGURE)(
 486   IN EFI_DHCP4_PROTOCOL       *This,
 487   IN EFI_DHCP4_CONFIG_DATA    *Dhcp4CfgData  OPTIONAL
 488   );
 489
 490
 491 /**
 492   Starts the DHCP configuration process.
 493
 494   The Start() function starts the DHCP configuration process. This function can
 495   be called only when the EFI DHCPv4 Protocol driver is in the Dhcp4Init or
 496   Dhcp4InitReboot state.
 497   If the DHCP process completes successfully, the state of the EFI DHCPv4 Protocol
 498   driver will be transferred through Dhcp4Selecting and Dhcp4Requesting to the
 499   Dhcp4Bound state. The CompletionEvent will then be signaled if it is not NULL.
 500   If the process aborts, either by the user or by some unexpected network error,
 501   the state is restored to the Dhcp4Init state. The Start() function can be called
 502   again to restart the process.
 503   Refer to RFC 2131 for precise state transitions during this process. At the
 504   time when each event occurs in this process, the callback function that was set
 505   by EFI_DHCP4_PROTOCOL.Configure() will be called and the user can take this
 506   opportunity to control the process.
 507
 508   @param  This            The pointer to the EFI_DHCP4_PROTOCOL instance.
 509   @param  CompletionEvent If not NULL, it indicates the event that will be signaled when the
 510                           EFI DHCPv4 Protocol driver is transferred into the
 511                           Dhcp4Bound state or when the DHCP process is aborted.
 512                           EFI_DHCP4_PROTOCOL.GetModeData() can be called to
 513                           check the completion status. If NULL,
 514                           EFI_DHCP4_PROTOCOL.Start() will wait until the driver
 515                           is transferred into the Dhcp4Bound state or the process fails.
 516
 517   @retval EFI_SUCCESS           The DHCP configuration process has started, or it has completed
 518                                 when CompletionEvent is NULL.
 519   @retval EFI_NOT_STARTED       The EFI DHCPv4 Protocol driver is in the Dhcp4Stopped
 520                                 state. EFI_DHCP4_PROTOCOL. Configure() needs to be called.
 521   @retval EFI_INVALID_PARAMETER This is NULL.
 522   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 523   @retval EFI_TIMEOUT           The DHCP configuration process failed because no response was
 524                                 received from the server within the specified timeout value.
 525   @retval EFI_ABORTED           The user aborted the DHCP process.
 526   @retval EFI_ALREADY_STARTED   Some other EFI DHCPv4 Protocol instance already started the
 527                                 DHCP process.
 528   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 529   @retval EFI_NO_MEDIA          There was a media error.
 530
 531 **/
 532 typedef
 533 EFI_STATUS
 534 (EFIAPI *EFI_DHCP4_START)(
 535   IN EFI_DHCP4_PROTOCOL       *This,
 536   IN EFI_EVENT                CompletionEvent   OPTIONAL
 537   );
 538
 539 /**
 540   Extends the lease time by sending a request packet.
 541
 542   The RenewRebind() function is used to manually extend the lease time when the
 543   EFI DHCPv4 Protocol driver is in the Dhcp4Bound state, and the lease time has
 544   not expired yet. This function will send a request packet to the previously
 545   found server (or to any server when RebindRequest is TRUE) and transfer the
 546   state into the Dhcp4Renewing state (or Dhcp4Rebinding when RebindingRequest is
 547   TRUE). When a response is received, the state is returned to Dhcp4Bound.
 548   If no response is received before the try count is exceeded (the RequestTryCount
 549   field that is specified in EFI_DHCP4_CONFIG_DATA) but before the lease time that
 550   was issued by the previous server expires, the driver will return to the Dhcp4Bound
 551   state, and the previous configuration is restored. The outgoing and incoming packets
 552   can be captured by the EFI_DHCP4_CALLBACK function.
 553
 554   @param  This            The pointer to the EFI_DHCP4_PROTOCOL instance.
 555   @param  RebindRequest   If TRUE, this function broadcasts the request packets and enters
 556                           the Dhcp4Rebinding state. Otherwise, it sends a unicast
 557                           request packet and enters the Dhcp4Renewing state.
 558   @param  CompletionEvent If not NULL, this event is signaled when the renew/rebind phase
 559                           completes or some error occurs.
 560                           EFI_DHCP4_PROTOCOL.GetModeData() can be called to
 561                           check the completion status. If NULL,
 562                           EFI_DHCP4_PROTOCOL.RenewRebind() will busy-wait
 563                           until the DHCP process finishes.
 564
 565   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the
 566                                 Dhcp4Renewing state or is back to the Dhcp4Bound state.
 567   @retval EFI_NOT_STARTED       The EFI DHCPv4 Protocol driver is in the Dhcp4Stopped
 568                                 state. EFI_DHCP4_PROTOCOL.Configure() needs to
 569                                 be called.
 570   @retval EFI_INVALID_PARAMETER This is NULL.
 571   @retval EFI_TIMEOUT           There was no response from the server when the try count was
 572                                 exceeded.
 573   @retval EFI_ACCESS_DENIED     The driver is not in the Dhcp4Bound state.
 574   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 575
 576 **/
 577 typedef
 578 EFI_STATUS
 579 (EFIAPI *EFI_DHCP4_RENEW_REBIND)(
 580   IN EFI_DHCP4_PROTOCOL       *This,
 581   IN BOOLEAN                  RebindRequest,
 582   IN EFI_EVENT                CompletionEvent  OPTIONAL
 583   );
 584
 585 /**
 586   Releases the current address configuration.
 587
 588   The Release() function releases the current configured IP address by doing either
 589   of the following:
 590   * Sending a DHCPRELEASE packet when the EFI DHCPv4 Protocol driver is in the
 591     Dhcp4Bound state
 592   * Setting the previously assigned IP address that was provided with the
 593     EFI_DHCP4_PROTOCOL.Configure() function to 0.0.0.0 when the driver is in
 594     Dhcp4InitReboot state
 595   After a successful call to this function, the EFI DHCPv4 Protocol driver returns
 596   to the Dhcp4Init state, and any subsequent incoming packets will be discarded silently.
 597
 598   @param  This                  The pointer to the EFI_DHCP4_PROTOCOL instance.
 599
 600   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Init phase.
 601   @retval EFI_INVALID_PARAMETER This is NULL.
 602   @retval EFI_ACCESS_DENIED     The EFI DHCPv4 Protocol driver is not Dhcp4InitReboot state.
 603   @retval EFI_DEVICE_ERROR      An unexpected system or network error occurred.
 604
 605 **/
 606 typedef
 607 EFI_STATUS
 608 (EFIAPI *EFI_DHCP4_RELEASE)(
 609   IN EFI_DHCP4_PROTOCOL       *This
 610   );
 611
 612 /**
 613   Stops the current address configuration.
 614
 615   The Stop() function is used to stop the DHCP configuration process. After this
 616   function is called successfully, the EFI DHCPv4 Protocol driver is transferred
 617   into the Dhcp4Stopped state. EFI_DHCP4_PROTOCOL.Configure() needs to be called
 618   before DHCP configuration process can be started again. This function can be
 619   called when the EFI DHCPv4 Protocol driver is in any state.
 620
 621   @param  This                  The pointer to the EFI_DHCP4_PROTOCOL instance.
 622
 623   @retval EFI_SUCCESS           The EFI DHCPv4 Protocol driver is now in the Dhcp4Stopped phase.
 624   @retval EFI_INVALID_PARAMETER This is NULL.
 625
 626 **/
 627 typedef
 628 EFI_STATUS
 629 (EFIAPI *EFI_DHCP4_STOP)(
 630   IN EFI_DHCP4_PROTOCOL       *This
 631   );
 632
 633 /**
 634   Builds a DHCP packet, given the options to be appended or deleted or replaced.
 635
 636   The Build() function is used to assemble a new packet from the original packet
 637   by replacing or deleting existing options or appending new options. This function
 638   does not change any state of the EFI DHCPv4 Protocol driver and can be used at
 639   any time.
 640
 641   @param  This        The pointer to the EFI_DHCP4_PROTOCOL instance.
 642   @param  SeedPacket  Initial packet to be used as a base for building new packet.
 643   @param  DeleteCount Number of opcodes in the DeleteList.
 644   @param  DeleteList  List of opcodes to be deleted from the seed packet.
 645                       Ignored if DeleteCount is zero.
 646   @param  AppendCount Number of entries in the OptionList.
 647   @param  AppendList  The pointer to a DHCP option list to be appended to SeedPacket.
 648                       If SeedPacket also contains options in this list, they are
 649                       replaced by new options (except pad option). Ignored if
 650                       AppendCount is zero. Type EFI_DHCP4_PACKET_OPTION
 651   @param  NewPacket   The pointer to storage for the pointer to the new allocated packet.
 652                       Use the EFI Boot Service FreePool() on the resulting pointer
 653                       when done with the packet.
 654
 655   @retval EFI_SUCCESS           The new packet was built.
 656   @retval EFI_OUT_OF_RESOURCES  Storage for the new packet could not be allocated.
 657   @retval EFI_INVALID_PARAMETER One or more of the following conditions is TRUE:
 658                                 This is NULL.
 659                                 SeedPacket is NULL.
 660                                 SeedPacket is not a well-formed DHCP packet.
 661                                 AppendCount is not zero and AppendList is NULL.
 662                                 DeleteCount is not zero and DeleteList is NULL.
 663                                 NewPacket is NULL
 664                                 Both DeleteCount and AppendCount are zero and
 665                                 NewPacket is not NULL.
 666
 667 **/
 668 typedef
 669 EFI_STATUS
 670 (EFIAPI *EFI_DHCP4_BUILD)(
 671   IN  EFI_DHCP4_PROTOCOL      *This,
 672   IN  EFI_DHCP4_PACKET        *SeedPacket,
 673   IN  UINT32                  DeleteCount,
 674   IN  UINT8                   *DeleteList         OPTIONAL,
 675   IN  UINT32                  AppendCount,
 676   IN  EFI_DHCP4_PACKET_OPTION *AppendList[]       OPTIONAL,
 677   OUT EFI_DHCP4_PACKET        **NewPacket
 678   );
 679
 680
 681 /**
 682   Transmits a DHCP formatted packet and optionally waits for responses.
 683
 684   The TransmitReceive() function is used to transmit a DHCP packet and optionally
 685   wait for the response from servers. This function does not change the state of
 686   the EFI DHCPv4 Protocol driver. It can be used at any time because of this.
 687
 688   @param  This    The pointer to the EFI_DHCP4_PROTOCOL instance.
 689   @param  Token   The pointer to the EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN structure.
 690
 691   @retval EFI_SUCCESS           The packet was successfully queued for transmission.
 692   @retval EFI_INVALID_PARAMETER One or more of the following conditions is TRUE:
 693                                 This is NULL.
 694                                 Token.RemoteAddress is zero.
 695                                 Token.Packet is NULL.
 696                                 Token.Packet is not a well-formed DHCP packet.
 697                                 The transaction ID in Token.Packet is in use by another DHCP process.
 698   @retval EFI_NOT_READY         The previous call to this function has not finished yet. Try to call
 699                                 this function after collection process completes.
 700   @retval EFI_NO_MAPPING        The default station address is not available yet.
 701   @retval EFI_OUT_OF_RESOURCES  Required system resources could not be allocated.
 702   @retval EFI_UNSUPPORTED       The implementation doesn't support this function
 703   @retval Others                Some other unexpected error occurred.
 704
 705 **/
 706 typedef
 707 EFI_STATUS
 708 (EFIAPI *EFI_DHCP4_TRANSMIT_RECEIVE)(
 709   IN EFI_DHCP4_PROTOCOL                *This,
 710   IN EFI_DHCP4_TRANSMIT_RECEIVE_TOKEN  *Token
 711   );
 712
 713
 714 /**
 715   Parses the packed DHCP option data.
 716
 717   The Parse() function is used to retrieve the option list from a DHCP packet.
 718   If *OptionCount isn't zero, and there is enough space for all the DHCP options
 719   in the Packet, each element of PacketOptionList is set to point to somewhere in
 720   the Packet->Dhcp4.Option where a new DHCP option begins. If RFC3396 is supported,
 721   the caller should reassemble the parsed DHCP options to get the final result.
 722   If *OptionCount is zero or there isn't enough space for all of them, the number
 723   of DHCP options in the Packet is returned in OptionCount.
 724
 725   @param  This             The pointer to the EFI_DHCP4_PROTOCOL instance.
 726   @param  Packet           The pointer to packet to be parsed.
 727   @param  OptionCount      On input, the number of entries in the PacketOptionList.
 728                            On output, the number of entries that were written into the
 729                            PacketOptionList.
 730   @param  PacketOptionList A list of packet option entries to be filled in. End option or pad
 731                            options are not included.
 732
 733   @retval EFI_SUCCESS           The packet was successfully parsed.
 734   @retval EFI_INVALID_PARAMETER One or more of the following conditions is TRUE:
 735                                 This is NULL.
 736                                 The packet is NULL.
 737                                 The packet is not a well-formed DHCP packet.
 738                                 OptionCount is NULL.
 739   @retval EFI_BUFFER_TOO_SMALL  One or more of the following conditions is TRUE:
 740                                 1) *OptionCount is smaller than the number of options that
 741                                 were found in the Packet.
 742                                 2) PacketOptionList is NULL.
 743   @retval EFI_OUT_OF_RESOURCE   The packet failed to parse because of a resource shortage.
 744
 745 **/
 746 typedef
 747 EFI_STATUS
 748 (EFIAPI *EFI_DHCP4_PARSE)(
 749   IN EFI_DHCP4_PROTOCOL        *This,
 750   IN EFI_DHCP4_PACKET          *Packet,
 751   IN OUT UINT32                *OptionCount,
 752   OUT EFI_DHCP4_PACKET_OPTION  *PacketOptionList[]  OPTIONAL
 753   );
 754
 755 ///
 756 /// This protocol is used to collect configuration information for the EFI IPv4 Protocol drivers
 757 /// and to provide DHCPv4 server and PXE boot server discovery services.
 758 ///
 759 struct _EFI_DHCP4_PROTOCOL {
 760   EFI_DHCP4_GET_MODE_DATA      GetModeData;
 761   EFI_DHCP4_CONFIGURE          Configure;
 762   EFI_DHCP4_START              Start;
 763   EFI_DHCP4_RENEW_REBIND       RenewRebind;
 764   EFI_DHCP4_RELEASE            Release;
 765   EFI_DHCP4_STOP               Stop;
 766   EFI_DHCP4_BUILD              Build;
 767   EFI_DHCP4_TRANSMIT_RECEIVE   TransmitReceive;
 768   EFI_DHCP4_PARSE              Parse;
 769 };
 770
 771 extern EFI_GUID gEfiDhcp4ProtocolGuid;
 772 extern EFI_GUID gEfiDhcp4ServiceBindingProtocolGuid;
 773
 774 #endif