NetworkPkg/DnsDxe/DnsImpl.h

   1 /** @file
   2 DnsDxe support functions implementation.
   3
   4 Copyright (c) 2015 - 2017, Intel Corporation. All rights reserved.<BR>
   5 This program and the accompanying materials
   6 are licensed and made available under the terms and conditions of the BSD License
   7 which accompanies this distribution.  The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #ifndef __EFI_DNS_IMPL_H_
  16 #define __EFI_DNS_IMPL_H_
  17
  18 #include <Uefi.h>
  19
  20 //
  21 // Libraries classes
  22 //
  23 #include <Library/BaseLib.h>
  24 #include <Library/UefiLib.h>
  25 #include <Library/UefiBootServicesTableLib.h>
  26 #include <Library/UefiDriverEntryPoint.h>
  27 #include <Library/UefiRuntimeServicesTableLib.h>
  28 #include <Library/BaseMemoryLib.h>
  29 #include <Library/MemoryAllocationLib.h>
  30 #include <Library/NetLib.h>
  31 #include <Library/DebugLib.h>
  32 #include <Library/DpcLib.h>
  33 #include <Library/PrintLib.h>
  34 #include <Library/UdpIoLib.h>
  35
  36 //
  37 // UEFI Driver Model Protocols
  38 //
  39 #include <Protocol/DriverBinding.h>
  40 #include <Protocol/ComponentName2.h>
  41 #include <Protocol/ComponentName.h>
  42
  43 #include <Protocol/Udp4.h>
  44 #include <Protocol/Dhcp4.h>
  45 #include <Protocol/Dns4.h>
  46
  47 #include <Protocol/Udp6.h>
  48 #include <Protocol/Dhcp6.h>
  49 #include <Protocol/Dns6.h>
  50
  51 #include <Protocol/Ip4Config2.h>
  52
  53 #include "DnsDriver.h"
  54 #include "DnsDhcp.h"
  55
  56 //
  57 // Driver Version
  58 //
  59 #define DNS_VERSION  0x00000000
  60
  61 //
  62 // Protocol instances
  63 //
  64 extern EFI_COMPONENT_NAME_PROTOCOL   gDnsComponentName;
  65 extern EFI_COMPONENT_NAME2_PROTOCOL  gDnsComponentName2;
  66 extern EFI_UNICODE_STRING_TABLE      *gDnsControllerNameTable;
  67
  68 extern EFI_DRIVER_BINDING_PROTOCOL   gDns4DriverBinding;
  69 extern EFI_SERVICE_BINDING_PROTOCOL  mDns4ServiceBinding;
  70 extern EFI_DNS4_PROTOCOL             mDns4Protocol;
  71
  72 extern EFI_DRIVER_BINDING_PROTOCOL   gDns6DriverBinding;
  73 extern EFI_SERVICE_BINDING_PROTOCOL  mDns6ServiceBinding;
  74 extern EFI_DNS6_PROTOCOL             mDns6Protocol;
  75
  76 //
  77 // DNS related
  78 //
  79 #define DNS_SERVER_PORT   53
  80
  81 #define DNS_PROTOCOL_UDP   EFI_IP_PROTO_UDP
  82 #define DNS_PROTOCOL_TCP   EFI_IP_PROTO_TCP
  83
  84 #define DNS_STATE_UNCONFIGED     0
  85 #define DNS_STATE_CONFIGED       1
  86 #define DNS_STATE_DESTROY        2
  87
  88 #define DNS_DEFAULT_TIMEOUT      2
  89
  90 #define DNS_TIME_TO_GETMAP       5
  91
  92 #pragma pack(1)
  93
  94 typedef union _DNS_FLAGS  DNS_FLAGS;
  95
  96 typedef struct {
  97   LIST_ENTRY             AllCacheLink;
  98   EFI_DNS4_CACHE_ENTRY   DnsCache;
  99 } DNS4_CACHE;
 100
 101 typedef struct {
 102   LIST_ENTRY             AllCacheLink;
 103   EFI_DNS6_CACHE_ENTRY   DnsCache;
 104 } DNS6_CACHE;
 105
 106 typedef struct {
 107   LIST_ENTRY             AllServerLink;
 108   EFI_IPv4_ADDRESS       Dns4ServerIp;
 109 } DNS4_SERVER_IP;
 110
 111 typedef struct {
 112   LIST_ENTRY             AllServerLink;
 113   EFI_IPv6_ADDRESS       Dns6ServerIp;
 114 } DNS6_SERVER_IP;
 115
 116 typedef struct {
 117   UINT32                     RetryCounting;
 118   UINT32                     PacketToLive;
 119   CHAR16                     *QueryHostName;
 120   EFI_IPv4_ADDRESS           QueryIpAddress;
 121   BOOLEAN                    GeneralLookUp;
 122   EFI_DNS4_COMPLETION_TOKEN  *Token;
 123 } DNS4_TOKEN_ENTRY;
 124
 125 typedef struct {
 126   UINT32                     RetryCounting;
 127   UINT32                     PacketToLive;
 128   CHAR16                     *QueryHostName;
 129   EFI_IPv6_ADDRESS           QueryIpAddress;
 130   BOOLEAN                    GeneralLookUp;
 131   EFI_DNS6_COMPLETION_TOKEN  *Token;
 132 } DNS6_TOKEN_ENTRY;
 133
 134 union _DNS_FLAGS{
 135   struct {
 136     UINT16     RCode:4;
 137     UINT16     Zero:3;
 138     UINT16     RA:1;
 139     UINT16     RD:1;
 140     UINT16     TC:1;
 141     UINT16     AA:1;
 142     UINT16     OpCode:4;
 143     UINT16     QR:1;
 144   } Bits;
 145   UINT16  Uint16;
 146 };
 147
 148 #define DNS_FLAGS_QR_QUERY     0
 149 #define DNS_FLAGS_QR_RESPONSE  1
 150
 151 #define DNS_FLAGS_OPCODE_STANDARD     0
 152 #define DNS_FLAGS_OPCODE_INVERSE      1
 153 #define DNS_FLAGS_OPCODE_SERVER_STATE 2
 154
 155 #define DNS_FLAGS_RCODE_NO_ERROR    0
 156 #define DNS_FLAGS_RCODE_NAME_ERROR  3
 157
 158 typedef struct {
 159   UINT16      Identification;
 160   DNS_FLAGS   Flags;
 161   UINT16      QuestionsNum;
 162   UINT16      AnswersNum;
 163   UINT16      AuthorityNum;
 164   UINT16      AditionalNum;
 165 } DNS_HEADER;
 166
 167 typedef struct {
 168   UINT16      Type;
 169   UINT16      Class;
 170 } DNS_QUERY_SECTION;
 171
 172 typedef struct {
 173   UINT16      Type;
 174   UINT16      Class;
 175   UINT32      Ttl;
 176   UINT16      DataLength;
 177 } DNS_ANSWER_SECTION;
 178
 179 #define DNS4_DOMAIN  L"in-addr.arpa"
 180 #define DNS6_DOMAIN  L"IP6.ARPA"
 181
 182
 183 #pragma pack()
 184
 185 /**
 186   Remove TokenEntry from TokenMap.
 187
 188   @param[in] TokenMap          All DNSv4 Token entrys.
 189   @param[in] TokenEntry        TokenEntry need to be removed.
 190
 191   @retval EFI_SUCCESS          Remove TokenEntry from TokenMap sucessfully.
 192   @retval EFI_NOT_FOUND        TokenEntry is not found in TokenMap.
 193
 194 **/
 195 EFI_STATUS
 196 Dns4RemoveTokenEntry (
 197   IN NET_MAP                    *TokenMap,
 198   IN DNS4_TOKEN_ENTRY           *TokenEntry
 199   );
 200
 201 /**
 202   Remove TokenEntry from TokenMap.
 203
 204   @param[in] TokenMap           All DNSv6 Token entrys.
 205   @param[in] TokenEntry         TokenEntry need to be removed.
 206
 207   @retval EFI_SUCCESS           Remove TokenEntry from TokenMap sucessfully.
 208   @retval EFI_NOT_FOUND         TokenEntry is not found in TokenMap.
 209
 210 **/
 211 EFI_STATUS
 212 Dns6RemoveTokenEntry (
 213   IN NET_MAP                    *TokenMap,
 214   IN DNS6_TOKEN_ENTRY           *TokenEntry
 215   );
 216
 217 /**
 218   This function cancle the token specified by Arg in the Map.
 219
 220   @param[in]  Map             Pointer to the NET_MAP.
 221   @param[in]  Item            Pointer to the NET_MAP_ITEM.
 222   @param[in]  Arg             Pointer to the token to be cancelled. If NULL, all
 223                               the tokens in this Map will be cancelled.
 224                               This parameter is optional and may be NULL.
 225
 226   @retval EFI_SUCCESS         The token is cancelled if Arg is NULL, or the token
 227                               is not the same as that in the Item, if Arg is not
 228                               NULL.
 229   @retval EFI_ABORTED         Arg is not NULL, and the token specified by Arg is
 230                               cancelled.
 231
 232 **/
 233 EFI_STATUS
 234 EFIAPI
 235 Dns4CancelTokens (
 236   IN NET_MAP       *Map,
 237   IN NET_MAP_ITEM  *Item,
 238   IN VOID          *Arg OPTIONAL
 239   );
 240
 241 /**
 242   This function cancle the token specified by Arg in the Map.
 243
 244   @param[in]  Map             Pointer to the NET_MAP.
 245   @param[in]  Item            Pointer to the NET_MAP_ITEM.
 246   @param[in]  Arg             Pointer to the token to be cancelled. If NULL, all
 247                               the tokens in this Map will be cancelled.
 248                               This parameter is optional and may be NULL.
 249
 250   @retval EFI_SUCCESS         The token is cancelled if Arg is NULL, or the token
 251                               is not the same as that in the Item, if Arg is not
 252                               NULL.
 253   @retval EFI_ABORTED         Arg is not NULL, and the token specified by Arg is
 254                               cancelled.
 255
 256 **/
 257 EFI_STATUS
 258 EFIAPI
 259 Dns6CancelTokens (
 260   IN NET_MAP       *Map,
 261   IN NET_MAP_ITEM  *Item,
 262   IN VOID          *Arg OPTIONAL
 263   );
 264
 265 /**
 266   Get the TokenEntry from the TokensMap.
 267
 268   @param[in]  TokensMap           All DNSv4 Token entrys
 269   @param[in]  Token               Pointer to the token to be get.
 270   @param[out] TokenEntry          Pointer to TokenEntry corresponding Token.
 271
 272   @retval EFI_SUCCESS             Get the TokenEntry from the TokensMap sucessfully.
 273   @retval EFI_NOT_FOUND           TokenEntry is not found in TokenMap.
 274
 275 **/
 276 EFI_STATUS
 277 EFIAPI
 278 GetDns4TokenEntry (
 279   IN     NET_MAP                   *TokensMap,
 280   IN     EFI_DNS4_COMPLETION_TOKEN *Token,
 281      OUT DNS4_TOKEN_ENTRY          **TokenEntry
 282   );
 283
 284 /**
 285   Get the TokenEntry from the TokensMap.
 286
 287   @param[in]  TokensMap           All DNSv6 Token entrys
 288   @param[in]  Token               Pointer to the token to be get.
 289   @param[out] TokenEntry          Pointer to TokenEntry corresponding Token.
 290
 291   @retval EFI_SUCCESS             Get the TokenEntry from the TokensMap sucessfully.
 292   @retval EFI_NOT_FOUND           TokenEntry is not found in TokenMap.
 293
 294 **/
 295 EFI_STATUS
 296 EFIAPI
 297 GetDns6TokenEntry (
 298   IN     NET_MAP                   *TokensMap,
 299   IN     EFI_DNS6_COMPLETION_TOKEN *Token,
 300      OUT DNS6_TOKEN_ENTRY          **TokenEntry
 301   );
 302
 303 /**
 304   Cancel DNS4 tokens from the DNS4 instance.
 305
 306   @param[in]  Instance           Pointer to the DNS instance context data.
 307   @param[in]  Token              Pointer to the token to be canceled. If NULL, all
 308                                  tokens in this instance will be cancelled.
 309                                  This parameter is optional and may be NULL.
 310
 311   @retval EFI_SUCCESS            The Token is cancelled.
 312   @retval EFI_NOT_FOUND          The Token is not found.
 313
 314 **/
 315 EFI_STATUS
 316 Dns4InstanceCancelToken (
 317   IN DNS_INSTANCE               *Instance,
 318   IN EFI_DNS4_COMPLETION_TOKEN  *Token
 319   );
 320
 321 /**
 322   Cancel DNS6 tokens from the DNS6 instance.
 323
 324   @param[in]  Instance           Pointer to the DNS instance context data.
 325   @param[in]  Token              Pointer to the token to be canceled. If NULL, all
 326                                  tokens in this instance will be cancelled.
 327                                  This parameter is optional and may be NULL.
 328
 329   @retval EFI_SUCCESS            The Token is cancelled.
 330   @retval EFI_NOT_FOUND          The Token is not found.
 331
 332 **/
 333 EFI_STATUS
 334 Dns6InstanceCancelToken (
 335   IN DNS_INSTANCE               *Instance,
 336   IN EFI_DNS6_COMPLETION_TOKEN  *Token
 337   );
 338
 339 /**
 340   Free the resource related to the configure parameters.
 341
 342   @param  Config                 The DNS configure data
 343
 344 **/
 345 VOID
 346 Dns4CleanConfigure (
 347   IN OUT EFI_DNS4_CONFIG_DATA  *Config
 348   );
 349
 350 /**
 351   Free the resource related to the configure parameters.
 352
 353   @param  Config                 The DNS configure data
 354
 355 **/
 356 VOID
 357 Dns6CleanConfigure (
 358   IN OUT EFI_DNS6_CONFIG_DATA  *Config
 359   );
 360
 361 /**
 362   Allocate memory for configure parameter such as timeout value for Dst,
 363   then copy the configure parameter from Src to Dst.
 364
 365   @param[out]  Dst               The destination DHCP configure data.
 366   @param[in]   Src               The source DHCP configure data.
 367
 368   @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.
 369   @retval EFI_SUCCESS            The configure is copied.
 370
 371 **/
 372 EFI_STATUS
 373 Dns4CopyConfigure (
 374   OUT EFI_DNS4_CONFIG_DATA  *Dst,
 375   IN  EFI_DNS4_CONFIG_DATA  *Src
 376   );
 377
 378 /**
 379   Allocate memory for configure parameter such as timeout value for Dst,
 380   then copy the configure parameter from Src to Dst.
 381
 382   @param[out]  Dst               The destination DHCP configure data.
 383   @param[in]   Src               The source DHCP configure data.
 384
 385   @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.
 386   @retval EFI_SUCCESS            The configure is copied.
 387
 388 **/
 389 EFI_STATUS
 390 Dns6CopyConfigure (
 391   OUT EFI_DNS6_CONFIG_DATA  *Dst,
 392   IN  EFI_DNS6_CONFIG_DATA  *Src
 393   );
 394
 395 /**
 396   Callback of Dns packet. Does nothing.
 397
 398   @param Arg           The context.
 399
 400 **/
 401 VOID
 402 EFIAPI
 403 DnsDummyExtFree (
 404   IN VOID                   *Arg
 405   );
 406
 407 /**
 408   Poll the UDP to get the IP4 default address, which may be retrieved
 409   by DHCP.
 410
 411   The default time out value is 5 seconds. If IP has retrieved the default address,
 412   the UDP is reconfigured.
 413
 414   @param  Instance               The DNS instance
 415   @param  UdpIo                  The UDP_IO to poll
 416   @param  UdpCfgData             The UDP configure data to reconfigure the UDP_IO
 417
 418   @retval TRUE                   The default address is retrieved and UDP is reconfigured.
 419   @retval FALSE                  Some error occured.
 420
 421 **/
 422 BOOLEAN
 423 Dns4GetMapping (
 424   IN DNS_INSTANCE           *Instance,
 425   IN UDP_IO                 *UdpIo,
 426   IN EFI_UDP4_CONFIG_DATA   *UdpCfgData
 427   );
 428
 429 /**
 430   Configure the opened Udp6 instance until the corresponding Ip6 instance
 431   has been configured.
 432
 433   @param  Instance               The DNS instance
 434   @param  UdpIo                  The UDP_IO to poll
 435   @param  UdpCfgData             The UDP configure data to reconfigure the UDP_IO
 436
 437   @retval TRUE                   Configure the Udp6 instance successfully.
 438   @retval FALSE                  Some error occured.
 439
 440 **/
 441 BOOLEAN
 442 Dns6GetMapping (
 443   IN DNS_INSTANCE           *Instance,
 444   IN UDP_IO                 *UdpIo,
 445   IN EFI_UDP6_CONFIG_DATA   *UdpCfgData
 446   );
 447
 448 /**
 449   Configure the UDP.
 450
 451   @param  Instance               The DNS session
 452   @param  UdpIo                  The UDP_IO instance
 453
 454   @retval EFI_SUCCESS            The UDP is successfully configured for the
 455                                  session.
 456
 457 **/
 458 EFI_STATUS
 459 Dns4ConfigUdp (
 460   IN DNS_INSTANCE           *Instance,
 461   IN UDP_IO                 *UdpIo
 462   );
 463
 464 /**
 465   Configure the UDP.
 466
 467   @param  Instance               The DNS session
 468   @param  UdpIo                  The UDP_IO instance
 469
 470   @retval EFI_SUCCESS            The UDP is successfully configured for the
 471                                  session.
 472
 473 **/
 474 EFI_STATUS
 475 Dns6ConfigUdp (
 476   IN DNS_INSTANCE           *Instance,
 477   IN UDP_IO                 *UdpIo
 478   );
 479
 480 /**
 481   Update Dns4 cache to shared list of caches of all DNSv4 instances.
 482
 483   @param  Dns4CacheList      All Dns4 cache list.
 484   @param  DeleteFlag         If FALSE, this function is to add one entry to the DNS Cache.
 485                              If TRUE, this function will delete matching DNS Cache entry.
 486   @param  Override           If TRUE, the matching DNS cache entry will be overwritten with the supplied parameter.
 487                              If FALSE, EFI_ACCESS_DENIED will be returned if the entry to be added is already exists.
 488   @param  DnsCacheEntry      Entry Pointer to DNS Cache entry.
 489
 490   @retval EFI_SUCCESS        Update Dns4 cache successfully.
 491   @retval Others             Failed to update Dns4 cache.
 492
 493 **/
 494 EFI_STATUS
 495 EFIAPI
 496 UpdateDns4Cache (
 497   IN LIST_ENTRY             *Dns4CacheList,
 498   IN BOOLEAN                DeleteFlag,
 499   IN BOOLEAN                Override,
 500   IN EFI_DNS4_CACHE_ENTRY   DnsCacheEntry
 501   );
 502
 503 /**
 504   Update Dns6 cache to shared list of caches of all DNSv6 instances.
 505
 506   @param  Dns6CacheList      All Dns6 cache list.
 507   @param  DeleteFlag         If FALSE, this function is to add one entry to the DNS Cache.
 508                              If TRUE, this function will delete matching DNS Cache entry.
 509   @param  Override           If TRUE, the matching DNS cache entry will be overwritten with the supplied parameter.
 510                              If FALSE, EFI_ACCESS_DENIED will be returned if the entry to be added is already exists.
 511   @param  DnsCacheEntry      Entry Pointer to DNS Cache entry.
 512
 513   @retval EFI_SUCCESS        Update Dns6 cache successfully.
 514   @retval Others             Failed to update Dns6 cache.
 515 **/
 516 EFI_STATUS
 517 EFIAPI
 518 UpdateDns6Cache (
 519   IN LIST_ENTRY             *Dns6CacheList,
 520   IN BOOLEAN                DeleteFlag,
 521   IN BOOLEAN                Override,
 522   IN EFI_DNS6_CACHE_ENTRY   DnsCacheEntry
 523   );
 524
 525 /**
 526   Add Dns4 ServerIp to common list of addresses of all configured DNSv4 server.
 527
 528   @param  Dns4ServerList    Common list of addresses of all configured DNSv4 server.
 529   @param  ServerIp          DNS server Ip.
 530
 531   @retval EFI_SUCCESS       Add Dns4 ServerIp to common list successfully.
 532   @retval Others            Failed to add Dns4 ServerIp to common list.
 533
 534 **/
 535 EFI_STATUS
 536 EFIAPI
 537 AddDns4ServerIp (
 538   IN LIST_ENTRY                *Dns4ServerList,
 539   IN EFI_IPv4_ADDRESS           ServerIp
 540   );
 541
 542 /**
 543   Add Dns6 ServerIp to common list of addresses of all configured DNSv6 server.
 544
 545   @param  Dns6ServerList    Common list of addresses of all configured DNSv6 server.
 546   @param  ServerIp          DNS server Ip.
 547
 548   @retval EFI_SUCCESS       Add Dns6 ServerIp to common list successfully.
 549   @retval Others            Failed to add Dns6 ServerIp to common list.
 550
 551 **/
 552 EFI_STATUS
 553 EFIAPI
 554 AddDns6ServerIp (
 555   IN LIST_ENTRY                *Dns6ServerList,
 556   IN EFI_IPv6_ADDRESS           ServerIp
 557   );
 558
 559 /**
 560   Find out whether the response is valid or invalid.
 561
 562   @param  TokensMap       All DNS transmittal Tokens entry.
 563   @param  Identification  Identification for queried packet.
 564   @param  Type            Type for queried packet.
 565   @param  Class           Class for queried packet.
 566   @param  Item            Return corresponding Token entry.
 567
 568   @retval TRUE            The response is valid.
 569   @retval FALSE           The response is invalid.
 570
 571 **/
 572 BOOLEAN
 573 IsValidDnsResponse (
 574   IN     NET_MAP      *TokensMap,
 575   IN     UINT16       Identification,
 576   IN     UINT16       Type,
 577   IN     UINT16       Class,
 578      OUT NET_MAP_ITEM **Item
 579   );
 580
 581 /**
 582   Parse Dns Response.
 583
 584   @param  Instance              The DNS instance
 585   @param  RxString              Received buffer.
 586   @param  Completed             Flag to indicate that Dns response is valid.
 587
 588   @retval EFI_SUCCESS           Parse Dns Response successfully.
 589   @retval Others                Failed to parse Dns Response.
 590
 591 **/
 592 EFI_STATUS
 593 ParseDnsResponse (
 594   IN OUT DNS_INSTANCE              *Instance,
 595   IN     UINT8                     *RxString,
 596      OUT BOOLEAN                   *Completed
 597   );
 598
 599 /**
 600   Parse response packet.
 601
 602   @param  Packet                The packets received.
 603   @param  EndPoint              The local/remote UDP access point
 604   @param  IoStatus              The status of the UDP receive
 605   @param  Context               The opaque parameter to the function.
 606
 607 **/
 608 VOID
 609 EFIAPI
 610 DnsOnPacketReceived (
 611   NET_BUF                   *Packet,
 612   UDP_END_POINT             *EndPoint,
 613   EFI_STATUS                IoStatus,
 614   VOID                      *Context
 615   );
 616
 617 /**
 618   Release the net buffer when packet is sent.
 619
 620   @param  Packet                The packets received.
 621   @param  EndPoint              The local/remote UDP access point
 622   @param  IoStatus              The status of the UDP receive
 623   @param  Context               The opaque parameter to the function.
 624
 625 **/
 626 VOID
 627 EFIAPI
 628 DnsOnPacketSent (
 629   NET_BUF                   *Packet,
 630   UDP_END_POINT             *EndPoint,
 631   EFI_STATUS                IoStatus,
 632   VOID                      *Context
 633   );
 634
 635 /**
 636   Query request information.
 637
 638   @param  Instance              The DNS instance
 639   @param  Packet                The packet for querying request information.
 640
 641   @retval EFI_SUCCESS           Query request information successfully.
 642   @retval Others                Failed to query request information.
 643
 644 **/
 645 EFI_STATUS
 646 DoDnsQuery (
 647   IN  DNS_INSTANCE              *Instance,
 648   IN  NET_BUF                   *Packet
 649   );
 650
 651 /**
 652   Construct the Packet according query section.
 653
 654   @param  Instance              The DNS instance
 655   @param  QueryName             Queried Name
 656   @param  Type                  Queried Type
 657   @param  Class                 Queried Class
 658   @param  Packet                The packet for query
 659
 660   @retval EFI_SUCCESS           The packet is constructed.
 661   @retval Others                Failed to construct the Packet.
 662
 663 **/
 664 EFI_STATUS
 665 ConstructDNSQuery (
 666   IN  DNS_INSTANCE              *Instance,
 667   IN  CHAR8                     *QueryName,
 668   IN  UINT16                    Type,
 669   IN  UINT16                    Class,
 670   OUT NET_BUF                   **Packet
 671   );
 672
 673 /**
 674   Retransmit the packet.
 675
 676   @param  Instance              The DNS instance
 677   @param  Packet                Retransmit the packet
 678
 679   @retval EFI_SUCCESS           The packet is retransmitted.
 680   @retval Others                Failed to retransmit.
 681
 682 **/
 683 EFI_STATUS
 684 DnsRetransmit (
 685   IN DNS_INSTANCE        *Instance,
 686   IN NET_BUF             *Packet
 687   );
 688
 689 /**
 690   The timer ticking function for the DNS service.
 691
 692   @param  Event                 The ticking event
 693   @param  Context               The DNS service instance
 694
 695 **/
 696 VOID
 697 EFIAPI
 698 DnsOnTimerRetransmit (
 699   IN EFI_EVENT              Event,
 700   IN VOID                   *Context
 701   );
 702
 703 /**
 704   The timer ticking function for the DNS driver.
 705
 706   @param  Event                 The ticking event
 707   @param  Context               NULL
 708
 709 **/
 710 VOID
 711 EFIAPI
 712 DnsOnTimerUpdate (
 713   IN EFI_EVENT              Event,
 714   IN VOID                   *Context
 715   );
 716
 717
 718 /**
 719   Retrieve mode data of this DNS instance.
 720
 721   This function is used to retrieve DNS mode data for this DNS instance.
 722
 723   @param[in]   This               Pointer to EFI_DNS4_PROTOCOL instance.
 724   @param[out]  DnsModeData        Point to the mode data.
 725
 726   @retval EFI_SUCCESS             The operation completed successfully.
 727   @retval EFI_NOT_STARTED         When DnsConfigData is queried, no configuration data
 728                                   is available because this instance has not been
 729                                   configured.
 730   @retval EFI_INVALID_PARAMETER   This is NULL or DnsModeData is NULL.
 731   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
 732 **/
 733 EFI_STATUS
 734 EFIAPI
 735 Dns4GetModeData (
 736   IN  EFI_DNS4_PROTOCOL          *This,
 737   OUT EFI_DNS4_MODE_DATA         *DnsModeData
 738   );
 739
 740 /**
 741   Configure this DNS instance.
 742
 743   This function is used to configure DNS mode data for this DNS instance.
 744
 745   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 746   @param[in]  DnsConfigData       Point to the Configuration data.
 747
 748   @retval EFI_SUCCESS             The operation completed successfully.
 749   @retval EFI_UNSUPPORTED         The designated protocol is not supported.
 750   @retval EFI_INVALID_PARAMTER    Thisis NULL.
 751                                   The StationIp address provided in DnsConfigData is not a
 752                                   valid unicast.
 753                                   DnsServerList is NULL while DnsServerListCount
 754                                   is not ZERO.
 755                                   DnsServerListCount is ZERO while DnsServerList
 756                                   is not NULL
 757   @retval EFI_OUT_OF_RESOURCES    The DNS instance data or required space could not be
 758                                   allocated.
 759   @retval EFI_DEVICE_ERROR        An unexpected system or network error occurred. The
 760                                   EFI DNSv4 Protocol instance is not configured.
 761   @retval EFI_ALREADY_STARTED     Second call to Configure() with DnsConfigData. To
 762                                   reconfigure the instance the caller must call Configure()
 763                                   with NULL first to return driver to unconfigured state.
 764 **/
 765 EFI_STATUS
 766 EFIAPI
 767 Dns4Configure (
 768   IN EFI_DNS4_PROTOCOL           *This,
 769   IN EFI_DNS4_CONFIG_DATA        *DnsConfigData
 770   );
 771
 772 /**
 773   Host name to host address translation.
 774
 775   The HostNameToIp () function is used to translate the host name to host IP address. A
 776   type A query is used to get the one or more IP addresses for this host.
 777
 778   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 779   @param[in]  HostName            Host name.
 780   @param[in]  Token               Point to the completion token to translate host name
 781                                   to host address.
 782
 783   @retval EFI_SUCCESS             The operation completed successfully.
 784   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
 785                                   This is NULL.
 786                                   Token is NULL.
 787                                   Token.Event is NULL.
 788                                   HostName is NULL. HostName string is unsupported format.
 789   @retval EFI_NO_MAPPING          There's no source address is available for use.
 790   @retval EFI_NOT_STARTED         This instance has not been started.
 791 **/
 792 EFI_STATUS
 793 EFIAPI
 794 Dns4HostNameToIp (
 795   IN  EFI_DNS4_PROTOCOL          *This,
 796   IN  CHAR16                    *HostName,
 797   IN  EFI_DNS4_COMPLETION_TOKEN  *Token
 798   );
 799
 800 /**
 801   IPv4 address to host name translation also known as Reverse DNS lookup.
 802
 803   The IpToHostName() function is used to translate the host address to host name. A type PTR
 804   query is used to get the primary name of the host. Support of this function is optional.
 805
 806   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 807   @param[in]  IpAddress           Ip Address.
 808   @param[in]  Token               Point to the completion token to translate host
 809                                   address to host name.
 810
 811   @retval EFI_SUCCESS             The operation completed successfully.
 812   @retval EFI_UNSUPPORTED         This function is not supported.
 813   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
 814                                   This is NULL.
 815                                   Token is NULL.
 816                                   Token.Event is NULL.
 817                                   IpAddress is not valid IP address .
 818   @retval EFI_NO_MAPPING          There's no source address is available for use.
 819   @retval EFI_ALREADY_STARTED     This Token is being used in another DNS session.
 820   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
 821 **/
 822 EFI_STATUS
 823 EFIAPI
 824 Dns4IpToHostName (
 825   IN  EFI_DNS4_PROTOCOL             *This,
 826   IN  EFI_IPv4_ADDRESS              IpAddress,
 827   IN  EFI_DNS4_COMPLETION_TOKEN     *Token
 828   );
 829
 830 /**
 831   Retrieve arbitrary information from the DNS server.
 832
 833   This GeneralLookup() function retrieves arbitrary information from the DNS. The caller
 834   supplies a QNAME, QTYPE, and QCLASS, and all of the matching RRs are returned. All
 835   RR content (e.g., TTL) was returned. The caller need parse the returned RR to get
 836   required information. The function is optional.
 837
 838   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 839   @param[in]  QName               Pointer to Query Name.
 840   @param[in]  QType               Query Type.
 841   @param[in]  QClass              Query Name.
 842   @param[in]  Token               Point to the completion token to retrieve arbitrary
 843                                   information.
 844
 845   @retval EFI_SUCCESS             The operation completed successfully.
 846   @retval EFI_UNSUPPORTED         This function is not supported. Or the requested
 847                                   QType is not supported
 848   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
 849                                   This is NULL.
 850                                   Token is NULL.
 851                                   Token.Event is NULL.
 852                                   QName is NULL.
 853   @retval EFI_NO_MAPPING          There's no source address is available for use.
 854   @retval EFI_ALREADY_STARTED     This Token is being used in another DNS session.
 855   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
 856 **/
 857 EFI_STATUS
 858 EFIAPI
 859 Dns4GeneralLookUp (
 860   IN  EFI_DNS4_PROTOCOL                *This,
 861   IN  CHAR8                            *QName,
 862   IN  UINT16                           QType,
 863   IN  UINT16                           QClass,
 864   IN  EFI_DNS4_COMPLETION_TOKEN        *Token
 865   );
 866
 867 /**
 868   This function is to update the DNS Cache.
 869
 870   The UpdateDnsCache() function is used to add/delete/modify DNS cache entry. DNS cache
 871   can be normally dynamically updated after the DNS resolve succeeds. This function
 872   provided capability to manually add/delete/modify the DNS cache.
 873
 874   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 875   @param[in]  DeleteFlag          If FALSE, this function is to add one entry to the
 876                                   DNS Cahce. If TRUE, this function will delete
 877                                   matching DNS Cache entry.
 878   @param[in]  Override            If TRUE, the maching DNS cache entry will be
 879                                   overwritten with the supplied parameter. If FALSE,
 880                                   EFI_ACCESS_DENIED will be returned if the entry to
 881                                   be added is already existed.
 882   @param[in]  DnsCacheEntry       Pointer to DNS Cache entry.
 883
 884   @retval EFI_SUCCESS             The operation completed successfully.
 885   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
 886                                   This is NULL.
 887                                   DnsCacheEntry.HostName is NULL.
 888                                   DnsCacheEntry.IpAddress is NULL.
 889                                   DnsCacheEntry.Timeout is zero.
 890   @retval EFI_ACCESS_DENIED       The DNS cache entry already exists and Override is
 891                                   not TRUE.
 892 **/
 893 EFI_STATUS
 894 EFIAPI
 895 Dns4UpdateDnsCache (
 896   IN EFI_DNS4_PROTOCOL      *This,
 897   IN BOOLEAN               DeleteFlag,
 898   IN BOOLEAN               Override,
 899   IN EFI_DNS4_CACHE_ENTRY   DnsCacheEntry
 900   );
 901
 902 /**
 903   Polls for incoming data packets and processes outgoing data packets.
 904
 905   The Poll() function can be used by network drivers and applications to increase the
 906   rate that data packets are moved between the communications device and the transmit
 907   and receive queues.
 908   In some systems, the periodic timer event in the managed network driver may not poll
 909   the underlying communications device fast enough to transmit and/or receive all data
 910   packets without missing incoming packets or dropping outgoing packets. Drivers and
 911   applications that are experiencing packet loss should try calling the Poll()
 912   function more often.
 913
 914   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 915
 916   @retval EFI_SUCCESS             Incoming or outgoing data was processed.
 917   @retval EFI_NOT_STARTED         This EFI DNS Protocol instance has not been started.
 918   @retval EFI_INVALID_PARAMETER   This is NULL.
 919   @retval EFI_DEVICE_ERROR        An unexpected system or network error occurred.
 920   @retval EFI_TIMEOUT             Data was dropped out of the transmit and/or receive
 921                                   queue. Consider increasing the polling rate.
 922 **/
 923 EFI_STATUS
 924 EFIAPI
 925 Dns4Poll (
 926   IN EFI_DNS4_PROTOCOL    *This
 927   );
 928
 929 /**
 930   Abort an asynchronous DNS operation, including translation between IP and Host, and
 931   general look up behavior.
 932
 933   The Cancel() function is used to abort a pending resolution request. After calling
 934   this function, Token.Status will be set to EFI_ABORTED and then Token.Event will be
 935   signaled. If the token is not in one of the queues, which usually means that the
 936   asynchronous operation has completed, this function will not signal the token and
 937   EFI_NOT_FOUND is returned.
 938
 939   @param[in]  This                Pointer to EFI_DNS4_PROTOCOL instance.
 940   @param[in]  Token               Pointer to a token that has been issued by
 941                                   EFI_DNS4_PROTOCOL.HostNameToIp (),
 942                                   EFI_DNS4_PROTOCOL.IpToHostName() or
 943                                   EFI_DNS4_PROTOCOL.GeneralLookup().
 944                                   If NULL, all pending tokens are aborted.
 945
 946   @retval EFI_SUCCESS             Incoming or outgoing data was processed.
 947   @retval EFI_NOT_STARTED         This EFI DNS4 Protocol instance has not been started.
 948   @retval EFI_INVALID_PARAMETER   This is NULL.
 949   @retval EFI_NOT_FOUND           When Token is not NULL, and the asynchronous DNS
 950                                   operation was not found in the transmit queue. It
 951                                   was either completed or was not issued by
 952                                   HostNameToIp(), IpToHostName() or GeneralLookup().
 953 **/
 954 EFI_STATUS
 955 EFIAPI
 956 Dns4Cancel (
 957   IN  EFI_DNS4_PROTOCOL          *This,
 958   IN  EFI_DNS4_COMPLETION_TOKEN  *Token
 959   );
 960
 961
 962 /**
 963   Retrieve mode data of this DNS instance.
 964
 965   This function is used to retrieve DNS mode data for this DNS instance.
 966
 967   @param[in]   This                Pointer to EFI_DNS6_PROTOCOL instance.
 968   @param[out]  DnsModeData         Pointer to the caller-allocated storage for the
 969                                    EFI_DNS6_MODE_DATA data.
 970
 971   @retval EFI_SUCCESS             The operation completed successfully.
 972   @retval EFI_NOT_STARTED         When DnsConfigData is queried, no configuration data
 973                                   is available because this instance has not been
 974                                   configured.
 975   @retval EFI_INVALID_PARAMETER   This is NULL or DnsModeData is NULL.
 976   @retval EFI_OUT_OF_RESOURCE     Failed to allocate needed resources.
 977 **/
 978 EFI_STATUS
 979 EFIAPI
 980 Dns6GetModeData (
 981   IN  EFI_DNS6_PROTOCOL          *This,
 982   OUT EFI_DNS6_MODE_DATA         *DnsModeData
 983   );
 984
 985 /**
 986   Configure this DNS instance.
 987
 988   The Configure() function is used to set and change the configuration data for this
 989   EFI DNSv6 Protocol driver instance. Reset the DNS instance if DnsConfigData is NULL.
 990
 991   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
 992   @param[in]  DnsConfigData       Pointer to the configuration data structure. All associated
 993                                   storage to be allocated and released by caller.
 994
 995   @retval EFI_SUCCESS             The operation completed successfully.
 996   @retval EFI_INVALID_PARAMTER    This is NULL.
 997                                   The StationIp address provided in DnsConfigData is not zero and not a valid unicast.
 998                                   DnsServerList is NULL while DnsServerList Count is not ZERO.
 999                                   DnsServerList Count is ZERO while DnsServerList is not NULL.
1000   @retval EFI_OUT_OF_RESOURCES    The DNS instance data or required space could not be allocated.
1001   @retval EFI_DEVICE_ERROR        An unexpected system or network error occurred. The
1002                                   EFI DNSv6 Protocol instance is not configured.
1003   @retval EFI_UNSUPPORTED         The designated protocol is not supported.
1004   @retval EFI_ALREADY_STARTED     Second call to Configure() with DnsConfigData. To
1005                                   reconfigure the instance the caller must call Configure() with
1006                                   NULL first to return driver to unconfigured state.
1007 **/
1008 EFI_STATUS
1009 EFIAPI
1010 Dns6Configure (
1011   IN EFI_DNS6_PROTOCOL           *This,
1012   IN EFI_DNS6_CONFIG_DATA        *DnsConfigData
1013   );
1014
1015 /**
1016   Host name to host address translation.
1017
1018   The HostNameToIp () function is used to translate the host name to host IP address. A
1019   type AAAA query is used to get the one or more IPv6 addresses for this host.
1020
1021   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1022   @param[in]  HostName            Host name.
1023   @param[in]  Token               Point to the completion token to translate host name
1024                                   to host address.
1025
1026   @retval EFI_SUCCESS             The operation completed successfully.
1027   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
1028                                   This is NULL.
1029                                   Token is NULL.
1030                                   Token.Event is NULL.
1031                                   HostName is NULL or buffer contained unsupported characters.
1032   @retval EFI_NO_MAPPING          There's no source address is available for use.
1033   @retval EFI_ALREADY_STARTED     This Token is being used in another DNS session.
1034   @retval EFI_NOT_STARTED         This instance has not been started.
1035   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
1036 **/
1037 EFI_STATUS
1038 EFIAPI
1039 Dns6HostNameToIp (
1040   IN  EFI_DNS6_PROTOCOL          *This,
1041   IN  CHAR16                     *HostName,
1042   IN  EFI_DNS6_COMPLETION_TOKEN  *Token
1043   );
1044
1045 /**
1046   Host address to host name translation.
1047
1048   The IpToHostName () function is used to translate the host address to host name. A
1049   type PTR query is used to get the primary name of the host. Implementation can choose
1050   to support this function or not.
1051
1052   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1053   @param[in]  IpAddress           Ip Address.
1054   @param[in]  Token               Point to the completion token to translate host
1055                                   address to host name.
1056
1057   @retval EFI_SUCCESS             The operation completed successfully.
1058   @retval EFI_UNSUPPORTED         This function is not supported.
1059   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
1060                                   This is NULL.
1061                                   Token is NULL.
1062                                   Token.Event is NULL.
1063                                   IpAddress is not valid IP address.
1064   @retval EFI_NO_MAPPING          There's no source address is available for use.
1065   @retval EFI_NOT_STARTED         This instance has not been started.
1066   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
1067 **/
1068 EFI_STATUS
1069 EFIAPI
1070 Dns6IpToHostName (
1071   IN  EFI_DNS6_PROTOCOL             *This,
1072   IN  EFI_IPv6_ADDRESS              IpAddress,
1073   IN  EFI_DNS6_COMPLETION_TOKEN     *Token
1074   );
1075
1076 /**
1077   This function provides capability to retrieve arbitrary information from the DNS
1078   server.
1079
1080   This GeneralLookup() function retrieves arbitrary information from the DNS. The caller
1081   supplies a QNAME, QTYPE, and QCLASS, and all of the matching RRs are returned. All
1082   RR content (e.g., TTL) was returned. The caller need parse the returned RR to get
1083   required information. The function is optional. Implementation can choose to support
1084   it or not.
1085
1086   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1087   @param[in]  QName               Pointer to Query Name.
1088   @param[in]  QType               Query Type.
1089   @param[in]  QClass              Query Name.
1090   @param[in]  Token               Point to the completion token to retrieve arbitrary
1091                                   information.
1092
1093   @retval EFI_SUCCESS             The operation completed successfully.
1094   @retval EFI_UNSUPPORTED         This function is not supported. Or the requested
1095                                   QType is not supported
1096   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
1097                                   This is NULL.
1098                                   Token is NULL.
1099                                   Token.Event is NULL.
1100                                   QName is NULL.
1101   @retval EFI_NO_MAPPING          There's no source address is available for use.
1102   @retval EFI_NOT_STARTED         This instance has not been started.
1103   @retval EFI_OUT_OF_RESOURCES    Failed to allocate needed resources.
1104 **/
1105 EFI_STATUS
1106 EFIAPI
1107 Dns6GeneralLookUp (
1108   IN  EFI_DNS6_PROTOCOL                *This,
1109   IN  CHAR8                            *QName,
1110   IN  UINT16                           QType,
1111   IN  UINT16                           QClass,
1112   IN  EFI_DNS6_COMPLETION_TOKEN        *Token
1113   );
1114
1115 /**
1116   This function is to update the DNS Cache.
1117
1118   The UpdateDnsCache() function is used to add/delete/modify DNS cache entry. DNS cache
1119   can be normally dynamically updated after the DNS resolve succeeds. This function
1120   provided capability to manually add/delete/modify the DNS cache.
1121
1122   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1123   @param[in]  DeleteFlag          If FALSE, this function is to add one entry to the
1124                                   DNS Cahce. If TRUE, this function will delete
1125                                   matching DNS Cache entry.
1126   @param[in]  Override            If TRUE, the maching DNS cache entry will be
1127                                   overwritten with the supplied parameter. If FALSE,
1128                                   EFI_ACCESS_DENIED will be returned if the entry to
1129                                   be added is already existed.
1130   @param[in]  DnsCacheEntry       Pointer to DNS Cache entry.
1131
1132   @retval EFI_SUCCESS             The operation completed successfully.
1133   @retval EFI_INVALID_PARAMETER   One or more of the following conditions is TRUE:
1134                                   This is NULL.
1135                                   DnsCacheEntry.HostName is NULL.
1136                                   DnsCacheEntry.IpAddress is NULL.
1137                                   DnsCacheEntry.Timeout is zero.
1138   @retval EFI_ACCESS_DENIED       The DNS cache entry already exists and Override is
1139                                   not TRUE.
1140   @retval EFI_OUT_OF_RESOURCE     Failed to allocate needed resources.
1141 **/
1142 EFI_STATUS
1143 EFIAPI
1144 Dns6UpdateDnsCache (
1145   IN EFI_DNS6_PROTOCOL      *This,
1146   IN BOOLEAN               DeleteFlag,
1147   IN BOOLEAN               Override,
1148   IN EFI_DNS6_CACHE_ENTRY   DnsCacheEntry
1149   );
1150
1151 /**
1152   Polls for incoming data packets and processes outgoing data packets.
1153
1154   The Poll() function can be used by network drivers and applications to increase the
1155   rate that data packets are moved between the communications device and the transmit
1156   and receive queues.
1157
1158   In some systems, the periodic timer event in the managed network driver may not poll
1159   the underlying communications device fast enough to transmit and/or receive all data
1160   packets without missing incoming packets or dropping outgoing packets. Drivers and
1161   applications that are experiencing packet loss should try calling the Poll()
1162   function more often.
1163
1164   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1165
1166   @retval EFI_SUCCESS             Incoming or outgoing data was processed.
1167   @retval EFI_NOT_STARTED         This EFI DNS Protocol instance has not been started.
1168   @retval EFI_INVALID_PARAMETER   This is NULL.
1169   @retval EFI_NO_MAPPING          There is no source address is available for use.
1170   @retval EFI_DEVICE_ERROR        An unexpected system or network error occurred.
1171   @retval EFI_TIMEOUT             Data was dropped out of the transmit and/or receive
1172                                   queue. Consider increasing the polling rate.
1173 **/
1174 EFI_STATUS
1175 EFIAPI
1176 Dns6Poll (
1177   IN EFI_DNS6_PROTOCOL    *This
1178   );
1179
1180 /**
1181   Abort an asynchronous DNS operation, including translation between IP and Host, and
1182   general look up behavior.
1183
1184   The Cancel() function is used to abort a pending resolution request. After calling
1185   this function, Token.Status will be set to EFI_ABORTED and then Token.Event will be
1186   signaled. If the token is not in one of the queues, which usually means that the
1187   asynchronous operation has completed, this function will not signal the token and
1188   EFI_NOT_FOUND is returned.
1189
1190   @param[in]  This                Pointer to EFI_DNS6_PROTOCOL instance.
1191   @param[in]  Token               Pointer to a token that has been issued by
1192                                   EFI_DNS6_PROTOCOL.HostNameToIp (),
1193                                   EFI_DNS6_PROTOCOL.IpToHostName() or
1194                                   EFI_DNS6_PROTOCOL.GeneralLookup().
1195                                   If NULL, all pending tokens are aborted.
1196
1197   @retval EFI_SUCCESS             Incoming or outgoing data was processed.
1198   @retval EFI_NOT_STARTED         This EFI DNS6 Protocol instance has not been started.
1199   @retval EFI_INVALID_PARAMETER   This is NULL.
1200   @retval EFI_NO_MAPPING          There's no source address is available for use.
1201   @retval EFI_NOT_FOUND           When Token is not NULL, and the asynchronous DNS
1202                                   operation was not found in the transmit queue. It
1203                                   was either completed or was not issued by
1204                                   HostNameToIp(), IpToHostName() or GeneralLookup().
1205 **/
1206 EFI_STATUS
1207 EFIAPI
1208 Dns6Cancel (
1209   IN  EFI_DNS6_PROTOCOL          *This,
1210   IN  EFI_DNS6_COMPLETION_TOKEN  *Token
1211   );
1212
1213 #endif