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1 /** @file
2   Helper functions for configuring or getting the parameters relating to HTTP Boot.
3 
4 Copyright (c) 2016, 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 #include "HttpBootDxe.h"
16 #include <Library/UefiBootManagerLib.h>
17 
18 CHAR16  mHttpBootConfigStorageName[]     = L"HTTP_BOOT_CONFIG_IFR_NVDATA";
19 
20 /**
21   Add new boot option for HTTP boot.
22 
23   @param[in]  Private             Pointer to the driver private data.
24   @param[in]  UsingIpv6           Set to TRUE if creating boot option for IPv6.
25   @param[in]  Description         The description text of the boot option.
26   @param[in]  Uri                 The URI string of the boot file.
27 
28   @retval EFI_SUCCESS             The boot option is created successfully.
29   @retval Others                  Failed to create new boot option.
30 
31 **/
32 EFI_STATUS
HttpBootAddBootOption(IN HTTP_BOOT_PRIVATE_DATA * Private,IN BOOLEAN UsingIpv6,IN CHAR16 * Description,IN CHAR16 * Uri)33 HttpBootAddBootOption (
34   IN   HTTP_BOOT_PRIVATE_DATA   *Private,
35   IN   BOOLEAN                  UsingIpv6,
36   IN   CHAR16                   *Description,
37   IN   CHAR16                   *Uri
38   )
39 {
40   EFI_DEV_PATH                      *Node;
41   EFI_DEVICE_PATH_PROTOCOL          *TmpDevicePath;
42   EFI_DEVICE_PATH_PROTOCOL          *NewDevicePath;
43   UINTN                             Length;
44   CHAR8                             AsciiUri[URI_STR_MAX_SIZE];
45   EFI_STATUS                        Status;
46   UINTN                             Index;
47   EFI_BOOT_MANAGER_LOAD_OPTION      NewOption;
48 
49   NewDevicePath = NULL;
50   Node          = NULL;
51   TmpDevicePath = NULL;
52 
53   if (StrLen (Description) == 0) {
54     return EFI_INVALID_PARAMETER;
55   }
56 
57   //
58   // Convert the scheme to all lower case.
59   //
60   for (Index = 0; Index < StrLen (Uri); Index++) {
61     if (Uri[Index] == L':') {
62       break;
63     }
64     if (Uri[Index] >= L'A' && Uri[Index] <= L'Z') {
65       Uri[Index] -= (CHAR16)(L'A' - L'a');
66     }
67   }
68 
69   //
70   // Only accept empty URI, or http and https URI.
71   //
72   if ((StrLen (Uri) != 0) && (StrnCmp (Uri, L"http://", 7) != 0) && (StrnCmp (Uri, L"https://", 8) != 0)) {
73     return EFI_INVALID_PARAMETER;
74   }
75 
76   //
77   // Create a new device path by appending the IP node and URI node to
78   // the driver's parent device path
79   //
80   if (!UsingIpv6) {
81     Node = AllocateZeroPool (sizeof (IPv4_DEVICE_PATH));
82     if (Node == NULL) {
83       Status = EFI_OUT_OF_RESOURCES;
84       goto ON_EXIT;
85     }
86     Node->Ipv4.Header.Type    = MESSAGING_DEVICE_PATH;
87     Node->Ipv4.Header.SubType = MSG_IPv4_DP;
88     SetDevicePathNodeLength (Node, sizeof (IPv4_DEVICE_PATH));
89   } else {
90     Node = AllocateZeroPool (sizeof (IPv6_DEVICE_PATH));
91     if (Node == NULL) {
92       Status = EFI_OUT_OF_RESOURCES;
93       goto ON_EXIT;
94     }
95     Node->Ipv6.Header.Type     = MESSAGING_DEVICE_PATH;
96     Node->Ipv6.Header.SubType  = MSG_IPv6_DP;
97     SetDevicePathNodeLength (Node, sizeof (IPv6_DEVICE_PATH));
98   }
99   TmpDevicePath = AppendDevicePathNode (Private->ParentDevicePath, (EFI_DEVICE_PATH_PROTOCOL*) Node);
100   FreePool (Node);
101   if (TmpDevicePath == NULL) {
102     return EFI_OUT_OF_RESOURCES;
103   }
104   //
105   // Update the URI node with the input boot file URI.
106   //
107   UnicodeStrToAsciiStrS (Uri, AsciiUri, sizeof (AsciiUri));
108   Length = sizeof (EFI_DEVICE_PATH_PROTOCOL) + AsciiStrSize (AsciiUri);
109   Node = AllocatePool (Length);
110   if (Node == NULL) {
111     Status = EFI_OUT_OF_RESOURCES;
112     FreePool (TmpDevicePath);
113     goto ON_EXIT;
114   }
115   Node->DevPath.Type    = MESSAGING_DEVICE_PATH;
116   Node->DevPath.SubType = MSG_URI_DP;
117   SetDevicePathNodeLength (Node, Length);
118   CopyMem ((UINT8*) Node + sizeof (EFI_DEVICE_PATH_PROTOCOL), AsciiUri, AsciiStrSize (AsciiUri));
119   NewDevicePath = AppendDevicePathNode (TmpDevicePath, (EFI_DEVICE_PATH_PROTOCOL*) Node);
120   FreePool (Node);
121   FreePool (TmpDevicePath);
122   if (NewDevicePath == NULL) {
123     Status = EFI_OUT_OF_RESOURCES;
124     goto ON_EXIT;
125   }
126 
127   //
128   // Add a new load option.
129   //
130   Status = EfiBootManagerInitializeLoadOption (
131                  &NewOption,
132                  LoadOptionNumberUnassigned,
133                  LoadOptionTypeBoot,
134                  LOAD_OPTION_ACTIVE,
135                  Description,
136                  NewDevicePath,
137                  NULL,
138                  0
139                  );
140   if (EFI_ERROR (Status)) {
141     goto ON_EXIT;
142   }
143 
144   Status = EfiBootManagerAddLoadOptionVariable (&NewOption, (UINTN) -1);
145   EfiBootManagerFreeLoadOption (&NewOption);
146 
147 ON_EXIT:
148 
149   if (NewDevicePath != NULL) {
150     FreePool (NewDevicePath);
151   }
152 
153   return Status;
154 }
155 
156 /**
157 
158   This function allows the caller to request the current
159   configuration for one or more named elements. The resulting
160   string is in <ConfigAltResp> format. Also, any and all alternative
161   configuration strings shall be appended to the end of the
162   current configuration string. If they are, they must appear
163   after the current configuration. They must contain the same
164   routing (GUID, NAME, PATH) as the current configuration string.
165   They must have an additional description indicating the type of
166   alternative configuration the string represents,
167   "ALTCFG=<StringToken>". That <StringToken> (when
168   converted from Hex UNICODE to binary) is a reference to a
169   string in the associated string pack.
170 
171   @param[in]  This       Points to the EFI_HII_CONFIG_ACCESS_PROTOCOL.
172 
173   @param[in]  Request    A null-terminated Unicode string in
174                          <ConfigRequest> format. Note that this
175                          includes the routing information as well as
176                          the configurable name / value pairs. It is
177                          invalid for this string to be in
178                          <MultiConfigRequest> format.
179 
180   @param[out] Progress   On return, points to a character in the
181                          Request string. Points to the string's null
182                          terminator if request was successful. Points
183                          to the most recent "&" before the first
184                          failing name / value pair (or the beginning
185                          of the string if the failure is in the first
186                          name / value pair) if the request was not successful.
187 
188   @param[out] Results    A null-terminated Unicode string in
189                          <ConfigAltResp> format which has all values
190                          filled in for the names in the Request string.
191                          String to be allocated by the called function.
192 
193   @retval EFI_SUCCESS             The Results string is filled with the
194                                   values corresponding to all requested
195                                   names.
196 
197   @retval EFI_OUT_OF_RESOURCES    Not enough memory to store the
198                                   parts of the results that must be
199                                   stored awaiting possible future
200                                   protocols.
201 
202   @retval EFI_INVALID_PARAMETER   For example, passing in a NULL
203                                   for the Request parameter
204                                   would result in this type of
205                                   error. In this case, the
206                                   Progress parameter would be
207                                   set to NULL.
208 
209   @retval EFI_NOT_FOUND           Routing data doesn't match any
210                                   known driver. Progress set to the
211                                   first character in the routing header.
212                                   Note: There is no requirement that the
213                                   driver validate the routing data. It
214                                   must skip the <ConfigHdr> in order to
215                                   process the names.
216 
217   @retval EFI_INVALID_PARAMETER   Illegal syntax. Progress set
218                                   to most recent "&" before the
219                                   error or the beginning of the
220                                   string.
221 
222   @retval EFI_INVALID_PARAMETER   Unknown name. Progress points
223                                   to the & before the name in
224                                   question.
225 
226 **/
227 EFI_STATUS
228 EFIAPI
HttpBootFormExtractConfig(IN CONST EFI_HII_CONFIG_ACCESS_PROTOCOL * This,IN CONST EFI_STRING Request,OUT EFI_STRING * Progress,OUT EFI_STRING * Results)229 HttpBootFormExtractConfig (
230   IN  CONST EFI_HII_CONFIG_ACCESS_PROTOCOL   *This,
231   IN  CONST EFI_STRING                       Request,
232   OUT EFI_STRING                             *Progress,
233   OUT EFI_STRING                             *Results
234   )
235 {
236   EFI_STATUS                       Status;
237   UINTN                            BufferSize;
238   HTTP_BOOT_FORM_CALLBACK_INFO     *CallbackInfo;
239   EFI_STRING                       ConfigRequestHdr;
240   EFI_STRING                       ConfigRequest;
241   BOOLEAN                          AllocatedRequest;
242   UINTN                            Size;
243 
244   if (Progress == NULL || Results == NULL) {
245     return EFI_INVALID_PARAMETER;
246   }
247 
248   *Progress = Request;
249   if ((Request != NULL) && !HiiIsConfigHdrMatch (Request, &gHttpBootConfigGuid, mHttpBootConfigStorageName)) {
250     return EFI_NOT_FOUND;
251   }
252 
253   ConfigRequestHdr = NULL;
254   ConfigRequest    = NULL;
255   AllocatedRequest = FALSE;
256   Size             = 0;
257 
258   CallbackInfo = HTTP_BOOT_FORM_CALLBACK_INFO_FROM_CONFIG_ACCESS (This);
259   //
260   // Convert buffer data to <ConfigResp> by helper function BlockToConfig()
261   //
262   BufferSize = sizeof (HTTP_BOOT_CONFIG_IFR_NVDATA);
263   ZeroMem (&CallbackInfo->HttpBootNvData, BufferSize);
264   StrCpyS (CallbackInfo->HttpBootNvData.Description, DESCRIPTION_STR_MAX_SIZE / sizeof (CHAR16), HTTP_BOOT_DEFAULT_DESCRIPTION_STR);
265 
266   ConfigRequest = Request;
267   if ((Request == NULL) || (StrStr (Request, L"OFFSET") == NULL)) {
268     //
269     // Request has no request element, construct full request string.
270     // Allocate and fill a buffer large enough to hold the <ConfigHdr> template
271     // followed by "&OFFSET=0&WIDTH=WWWWWWWWWWWWWWWW" followed by a Null-terminator
272     //
273     ConfigRequestHdr = HiiConstructConfigHdr (&gHttpBootConfigGuid, mHttpBootConfigStorageName, CallbackInfo->ChildHandle);
274     Size = (StrLen (ConfigRequestHdr) + 32 + 1) * sizeof (CHAR16);
275     ConfigRequest = AllocateZeroPool (Size);
276     if (ConfigRequest == NULL) {
277       return EFI_OUT_OF_RESOURCES;
278     }
279     AllocatedRequest = TRUE;
280     UnicodeSPrint (ConfigRequest, Size, L"%s&OFFSET=0&WIDTH=%016LX", ConfigRequestHdr, (UINT64)BufferSize);
281     FreePool (ConfigRequestHdr);
282   }
283 
284   Status = gHiiConfigRouting->BlockToConfig (
285                                 gHiiConfigRouting,
286                                 ConfigRequest,
287                                 (UINT8 *) &CallbackInfo->HttpBootNvData,
288                                 BufferSize,
289                                 Results,
290                                 Progress
291                                 );
292 
293   //
294   // Free the allocated config request string.
295   //
296   if (AllocatedRequest) {
297     FreePool (ConfigRequest);
298     ConfigRequest = NULL;
299   }
300   //
301   // Set Progress string to the original request string.
302   //
303   if (Request == NULL) {
304     *Progress = NULL;
305   } else if (StrStr (Request, L"OFFSET") == NULL) {
306     *Progress = Request + StrLen (Request);
307   }
308 
309   return Status;
310 }
311 
312 /**
313 
314   This function applies changes in a driver's configuration.
315   Input is a Configuration, which has the routing data for this
316   driver followed by name / value configuration pairs. The driver
317   must apply those pairs to its configurable storage. If the
318   driver's configuration is stored in a linear block of data
319   and the driver's name / value pairs are in <BlockConfig>
320   format, it may use the ConfigToBlock helper function (above) to
321   simplify the job.
322 
323   @param[in]  This           Points to the EFI_HII_CONFIG_ACCESS_PROTOCOL.
324 
325   @param[in]  Configuration  A null-terminated Unicode string in
326                              <ConfigString> format.
327 
328   @param[out] Progress       A pointer to a string filled in with the
329                              offset of the most recent '&' before the
330                              first failing name / value pair (or the
331                              beginning of the string if the failure
332                              is in the first name / value pair) or
333                              the terminating NULL if all was
334                              successful.
335 
336   @retval EFI_SUCCESS             The results have been distributed or are
337                                   awaiting distribution.
338 
339   @retval EFI_OUT_OF_RESOURCES    Not enough memory to store the
340                                   parts of the results that must be
341                                   stored awaiting possible future
342                                   protocols.
343 
344   @retval EFI_INVALID_PARAMETERS  Passing in a NULL for the
345                                   Results parameter would result
346                                   in this type of error.
347 
348   @retval EFI_NOT_FOUND           Target for the specified routing data
349                                   was not found.
350 
351 **/
352 EFI_STATUS
353 EFIAPI
HttpBootFormRouteConfig(IN CONST EFI_HII_CONFIG_ACCESS_PROTOCOL * This,IN CONST EFI_STRING Configuration,OUT EFI_STRING * Progress)354 HttpBootFormRouteConfig (
355   IN  CONST EFI_HII_CONFIG_ACCESS_PROTOCOL   *This,
356   IN  CONST EFI_STRING                       Configuration,
357   OUT EFI_STRING                             *Progress
358   )
359 {
360   EFI_STATUS                       Status;
361   UINTN                            BufferSize;
362   HTTP_BOOT_FORM_CALLBACK_INFO     *CallbackInfo;
363   HTTP_BOOT_PRIVATE_DATA           *Private;
364 
365   if (Progress == NULL) {
366     return EFI_INVALID_PARAMETER;
367   }
368   *Progress = Configuration;
369 
370   if (Configuration == NULL) {
371     return EFI_INVALID_PARAMETER;
372   }
373 
374   //
375   // Check routing data in <ConfigHdr>.
376   // Note: there is no name for Name/Value storage, only GUID will be checked
377   //
378   if (!HiiIsConfigHdrMatch (Configuration, &gHttpBootConfigGuid, mHttpBootConfigStorageName)) {
379     return EFI_NOT_FOUND;
380   }
381 
382   CallbackInfo = HTTP_BOOT_FORM_CALLBACK_INFO_FROM_CONFIG_ACCESS (This);
383   Private      = HTTP_BOOT_PRIVATE_DATA_FROM_CALLBACK_INFO (CallbackInfo);
384 
385   BufferSize = sizeof (HTTP_BOOT_CONFIG_IFR_NVDATA);
386   ZeroMem (&CallbackInfo->HttpBootNvData, BufferSize);
387 
388   Status = gHiiConfigRouting->ConfigToBlock (
389                             gHiiConfigRouting,
390                             Configuration,
391                             (UINT8 *) &CallbackInfo->HttpBootNvData,
392                             &BufferSize,
393                             Progress
394                             );
395   if (EFI_ERROR (Status)) {
396     return Status;
397   }
398 
399   //
400   // Create a new boot option according to the configuration data.
401   //
402   HttpBootAddBootOption (
403     Private,
404     (CallbackInfo->HttpBootNvData.IpVersion == HTTP_BOOT_IP_VERSION_6) ? TRUE : FALSE,
405     CallbackInfo->HttpBootNvData.Description,
406     CallbackInfo->HttpBootNvData.Uri
407     );
408 
409   return EFI_SUCCESS;
410 }
411 
412 /**
413 
414   This function is called to provide results data to the driver.
415   This data consists of a unique key that is used to identify
416   which data is either being passed back or being asked for.
417 
418   @param[in]       This          Points to the EFI_HII_CONFIG_ACCESS_PROTOCOL.
419   @param[in]       Action        Specifies the type of action taken by the browser.
420   @param[in]       QuestionId    A unique value which is sent to the original
421                                  exporting driver so that it can identify the type
422                                  of data to expect. The format of the data tends to
423                                  vary based on the opcode that generated the callback.
424   @param[in]       Type          The type of value for the question.
425   @param[in, out]  Value         A pointer to the data being sent to the original
426                                  exporting driver.
427   @param[out]      ActionRequest On return, points to the action requested by the
428                                  callback function.
429 
430   @retval EFI_SUCCESS            The callback successfully handled the action.
431   @retval EFI_OUT_OF_RESOURCES   Not enough storage is available to hold the
432                                  variable and its data.
433   @retval EFI_DEVICE_ERROR       The variable could not be saved.
434   @retval EFI_UNSUPPORTED        The specified Action is not supported by the
435                                  callback.
436 **/
437 EFI_STATUS
438 EFIAPI
HttpBootFormCallback(IN CONST EFI_HII_CONFIG_ACCESS_PROTOCOL * This,IN EFI_BROWSER_ACTION Action,IN EFI_QUESTION_ID QuestionId,IN UINT8 Type,IN OUT EFI_IFR_TYPE_VALUE * Value,OUT EFI_BROWSER_ACTION_REQUEST * ActionRequest)439 HttpBootFormCallback (
440   IN CONST  EFI_HII_CONFIG_ACCESS_PROTOCOL   *This,
441   IN        EFI_BROWSER_ACTION               Action,
442   IN        EFI_QUESTION_ID                  QuestionId,
443   IN        UINT8                            Type,
444   IN OUT    EFI_IFR_TYPE_VALUE               *Value,
445   OUT       EFI_BROWSER_ACTION_REQUEST       *ActionRequest
446   )
447 {
448   EFI_INPUT_KEY                   Key;
449   UINTN                           Index;
450   CHAR16                          *Uri;
451   HTTP_BOOT_FORM_CALLBACK_INFO    *CallbackInfo;
452 
453   if (This == NULL || Value == NULL) {
454     return EFI_INVALID_PARAMETER;
455   }
456 
457   CallbackInfo = HTTP_BOOT_FORM_CALLBACK_INFO_FROM_CONFIG_ACCESS (This);
458 
459   if (Action != EFI_BROWSER_ACTION_CHANGING) {
460     return EFI_UNSUPPORTED;
461   }
462 
463   switch (QuestionId) {
464   case KEY_INITIATOR_URI:
465     //
466     // Get user input URI string
467     //
468     Uri = HiiGetString (CallbackInfo->RegisteredHandle, Value->string, NULL);
469     if (Uri == NULL) {
470       return EFI_UNSUPPORTED;
471     }
472 
473     //
474     // Convert the scheme to all lower case.
475     //
476     for (Index = 0; Index < StrLen (Uri); Index++) {
477       if (Uri[Index] == L':') {
478         break;
479       }
480       if (Uri[Index] >= L'A' && Uri[Index] <= L'Z') {
481         Uri[Index] -= (CHAR16)(L'A' - L'a');
482       }
483     }
484 
485     //
486     // Set the converted URI string back
487     //
488     HiiSetString (CallbackInfo->RegisteredHandle, Value->string, Uri, NULL);
489 
490     //
491     // The URI should be either an empty string (for corporate environment) ,or http(s) for home environment.
492     // Pop up a message box for other unsupported URI.
493     //
494     if ((StrLen (Uri) != 0) && (StrnCmp (Uri, L"http://", 7) != 0) && (StrnCmp (Uri, L"https://", 8) != 0)) {
495       CreatePopUp (
496         EFI_LIGHTGRAY | EFI_BACKGROUND_BLUE,
497         &Key,
498         L"ERROR: Unsupported URI!",
499         L"Only supports HTTP and HTTPS",
500         NULL
501         );
502     }
503 
504     FreePool (Uri);
505     break;
506 
507   default:
508     break;
509   }
510 
511   return EFI_SUCCESS;
512 }
513 
514 /**
515   Initialize the configuration form.
516 
517   @param[in]  Private             Pointer to the driver private data.
518 
519   @retval EFI_SUCCESS             The configuration form is initialized.
520   @retval EFI_OUT_OF_RESOURCES    Failed to allocate memory.
521 
522 **/
523 EFI_STATUS
HttpBootConfigFormInit(IN HTTP_BOOT_PRIVATE_DATA * Private)524 HttpBootConfigFormInit (
525   IN HTTP_BOOT_PRIVATE_DATA     *Private
526   )
527 {
528   EFI_STATUS                        Status;
529   HTTP_BOOT_FORM_CALLBACK_INFO      *CallbackInfo;
530   VENDOR_DEVICE_PATH                VendorDeviceNode;
531   CHAR16                            *MacString;
532   CHAR16                            *OldMenuString;
533   CHAR16                            MenuString[128];
534 
535   CallbackInfo = &Private->CallbackInfo;
536 
537   if (CallbackInfo->Initilized) {
538     return EFI_SUCCESS;
539   }
540 
541   CallbackInfo->Signature = HTTP_BOOT_FORM_CALLBACK_INFO_SIGNATURE;
542 
543   //
544   // Construct device path node for EFI HII Config Access protocol,
545   // which consists of controller physical device path and one hardware
546   // vendor guid node.
547   //
548   ZeroMem (&VendorDeviceNode, sizeof (VENDOR_DEVICE_PATH));
549   VendorDeviceNode.Header.Type    = HARDWARE_DEVICE_PATH;
550   VendorDeviceNode.Header.SubType = HW_VENDOR_DP;
551   CopyGuid (&VendorDeviceNode.Guid, &gEfiCallerIdGuid);
552   SetDevicePathNodeLength (&VendorDeviceNode.Header, sizeof (VENDOR_DEVICE_PATH));
553   CallbackInfo->HiiVendorDevicePath = AppendDevicePathNode (
554                                         Private->ParentDevicePath,
555                                         (EFI_DEVICE_PATH_PROTOCOL *) &VendorDeviceNode
556                                         );
557   if (CallbackInfo->HiiVendorDevicePath == NULL) {
558     Status = EFI_OUT_OF_RESOURCES;
559     goto Error;
560   }
561 
562   CallbackInfo->ConfigAccess.ExtractConfig = HttpBootFormExtractConfig;
563   CallbackInfo->ConfigAccess.RouteConfig   = HttpBootFormRouteConfig;
564   CallbackInfo->ConfigAccess.Callback      = HttpBootFormCallback;
565 
566   //
567   // Install Device Path Protocol and Config Access protocol to driver handle.
568   //
569   Status = gBS->InstallMultipleProtocolInterfaces (
570                   &CallbackInfo->ChildHandle,
571                   &gEfiDevicePathProtocolGuid,
572                   CallbackInfo->HiiVendorDevicePath,
573                   &gEfiHiiConfigAccessProtocolGuid,
574                   &CallbackInfo->ConfigAccess,
575                   NULL
576                   );
577   if (EFI_ERROR (Status)) {
578     goto Error;
579   }
580 
581   //
582   // Publish our HII data.
583   //
584   CallbackInfo->RegisteredHandle = HiiAddPackages (
585                                      &gHttpBootConfigGuid,
586                                      CallbackInfo->ChildHandle,
587                                      HttpBootDxeStrings,
588                                      HttpBootConfigVfrBin,
589                                      NULL
590                                      );
591   if (CallbackInfo->RegisteredHandle == NULL) {
592     Status = EFI_OUT_OF_RESOURCES;
593     goto Error;
594   }
595 
596   //
597   // Append MAC string in the menu help string
598   //
599   Status = NetLibGetMacString (Private->Controller, NULL, &MacString);
600   if (!EFI_ERROR (Status)) {
601     OldMenuString = HiiGetString (
602                       CallbackInfo->RegisteredHandle,
603                       STRING_TOKEN (STR_HTTP_BOOT_CONFIG_FORM_HELP),
604                       NULL
605                       );
606     UnicodeSPrint (MenuString, 128, L"%s (MAC:%s)", OldMenuString, MacString);
607     HiiSetString (
608       CallbackInfo->RegisteredHandle,
609       STRING_TOKEN (STR_HTTP_BOOT_CONFIG_FORM_HELP),
610       MenuString,
611       NULL
612       );
613 
614     FreePool (MacString);
615     FreePool (OldMenuString);
616 
617     CallbackInfo->Initilized = TRUE;
618     return EFI_SUCCESS;
619   }
620 
621 Error:
622 
623   HttpBootConfigFormUnload (Private);
624   return Status;
625 }
626 
627 /**
628   Unload the configuration form, this includes: delete all the configuration
629   entries, uninstall the form callback protocol, and free the resources used.
630   The form will only be unload completely when both IP4 and IP6 stack are stopped.
631 
632   @param[in]  Private             Pointer to the driver private data.
633 
634   @retval EFI_SUCCESS             The configuration form is unloaded.
635   @retval Others                  Failed to unload the form.
636 
637 **/
638 EFI_STATUS
HttpBootConfigFormUnload(IN HTTP_BOOT_PRIVATE_DATA * Private)639 HttpBootConfigFormUnload (
640   IN HTTP_BOOT_PRIVATE_DATA     *Private
641   )
642 {
643   HTTP_BOOT_FORM_CALLBACK_INFO      *CallbackInfo;
644 
645   if (Private->Ip4Nic != NULL || Private->Ip6Nic != NULL) {
646     //
647     // Only unload the configuration form when both IP4 and IP6 stack are stopped.
648     //
649     return EFI_SUCCESS;
650   }
651 
652   CallbackInfo = &Private->CallbackInfo;
653   if (CallbackInfo->ChildHandle != NULL) {
654     //
655     // Uninstall EFI_HII_CONFIG_ACCESS_PROTOCOL
656     //
657     gBS->UninstallMultipleProtocolInterfaces (
658            CallbackInfo->ChildHandle,
659            &gEfiDevicePathProtocolGuid,
660            CallbackInfo->HiiVendorDevicePath,
661            &gEfiHiiConfigAccessProtocolGuid,
662            &CallbackInfo->ConfigAccess,
663            NULL
664            );
665     CallbackInfo->ChildHandle = NULL;
666   }
667 
668   if (CallbackInfo->HiiVendorDevicePath != NULL) {
669     FreePool (CallbackInfo->HiiVendorDevicePath);
670     CallbackInfo->HiiVendorDevicePath = NULL;
671   }
672 
673   if (CallbackInfo->RegisteredHandle != NULL) {
674     //
675     // Remove HII package list
676     //
677     HiiRemovePackages (CallbackInfo->RegisteredHandle);
678     CallbackInfo->RegisteredHandle = NULL;
679   }
680 
681   return EFI_SUCCESS;
682 }
683