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