OvmfPkg/PlatformDxe: Handle all requests in ExtractConfig and RouteConfig

Per the UEFI specification, if the Request argument in
EFI_HII_CONFIG_ACCESS_PROTOCOL.ExtractConfig() is NULL or does not contain
any request elements, the implementation should return all of the settings
being abstracted for the particular ConfigHdr reference.

The current implementation returns EFI_INVALID_PARAMETER if Request is
NULL or does not contain any request elements. Instead, construct
a new ConfigRequest to handle these cases per the specification.

In addition, per the UEFI specification, if the Configuration argument in
EFI_HII_CONFIG_ACCESS_PROTOCOL.RouteConfig() has a ConfigHdr that
specifies a non-existing target, the implementation should return
EFI_NOT_FOUND.

The current implementation returns EFI_INVALID_PARAMETER if Configuration
has a non-existing target in ConfigHdr. Instead, perform a check and
return EFI_NOT_FOUND in this case.

Signed-off-by: Dimitrije Pavlov <Dimitrije.Pavlov@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>

3 files changed, 116 insertions, 3 deletions

diff --git a/OvmfPkg/PlatformDxe/Platform.c b/OvmfPkg/PlatformDxe/Platform.c
index 4d432f18df..ac31fafbdc 100644
--- a/OvmfPkg/PlatformDxe/Platform.c
+++ b/OvmfPkg/PlatformDxe/Platform.c
@@ -109,6 +109,11 @@ STATIC EFI_EVENT  mGopEvent;
 STATIC VOID  *mGopTracker;

 

 //

+// The driver image handle, used to obtain the device path for <ConfigHdr>.

+//

+STATIC EFI_HANDLE  mImageHandle;

+

+//

 // Cache the resolutions we get from the GOP.

 //

 typedef struct {

@@ -229,6 +234,10 @@ ExtractConfig (
 {

   MAIN_FORM_STATE  MainFormState;

   EFI_STATUS       Status;

+  EFI_STRING       ConfigRequestHdr;

+  EFI_STRING       ConfigRequest;

+  UINTN            Size;

+  BOOLEAN          AllocatedRequest;

 

   DEBUG ((DEBUG_VERBOSE, "%a: Request=\"%s\"\n", __FUNCTION__, Request));

 

@@ -236,18 +245,73 @@ ExtractConfig (
     return EFI_INVALID_PARAMETER;

   }

 

+  ConfigRequestHdr = NULL;

+  ConfigRequest    = NULL;

+  Size             = 0;

+  AllocatedRequest = FALSE;

+

+  //

+  // Check if <ConfigHdr> matches the GUID and name

+  //

+  *Progress = Request;

+  if ((Request != NULL) &&

+      !HiiIsConfigHdrMatch (

+         Request,

+         &gOvmfPlatformConfigGuid,

+         mVariableName

+         )

+      )

+  {

+    return EFI_NOT_FOUND;

+  }

+

   Status = PlatformConfigToFormState (&MainFormState);

   if (EFI_ERROR (Status)) {

-    *Progress = Request;

     return Status;

   }

 

+  if ((Request == NULL) || (StrStr (Request, L"OFFSET") == NULL)) {

+    //

+    // Request has no <RequestElement>, so construct full request string.

+    // Allocate and fill a buffer large enough to hold <ConfigHdr>

+    // followed by "&OFFSET=0&WIDTH=WWWWWWWWWWWWWWWW" followed by a

+    // null terminator.

+    //

+    ConfigRequestHdr = HiiConstructConfigHdr (

+                         &gOvmfPlatformConfigGuid,

+                         mVariableName,

+                         mImageHandle

+                         );

+    if (ConfigRequestHdr == NULL) {

+      return EFI_OUT_OF_RESOURCES;

+    }

+

+    Size             = (StrLen (ConfigRequestHdr) + 32 + 1) * sizeof (CHAR16);

+    ConfigRequest    = AllocateZeroPool (Size);

+    AllocatedRequest = TRUE;

+    if (ConfigRequest == NULL) {

+      FreePool (ConfigRequestHdr);

+      return EFI_OUT_OF_RESOURCES;

+    }

+

+    UnicodeSPrint (

+      ConfigRequest,

+      Size,

+      L"%s&OFFSET=0&WIDTH=%016LX",

+      ConfigRequestHdr,

+      sizeof MainFormState

+      );

+    FreePool (ConfigRequestHdr);

+  } else {

+    ConfigRequest = Request;

+  }

+

   //

   // Answer the textual request keying off the binary form state.

   //

   Status = gHiiConfigRouting->BlockToConfig (

                                 gHiiConfigRouting,

-                                Request,

+                                ConfigRequest,

                                 (VOID *)&MainFormState,

                                 sizeof MainFormState,

                                 Results,

@@ -265,6 +329,33 @@ ExtractConfig (
     DEBUG ((DEBUG_VERBOSE, "%a: Results=\"%s\"\n", __FUNCTION__, *Results));

   }

 

+  //

+  // If we used a newly allocated ConfigRequest, update Progress to point to

+  // original Request instead of ConfigRequest.

+  //

+  if (Request == NULL) {

+    *Progress = NULL;

+  } else if (StrStr (Request, L"OFFSET") == NULL) {

+    if (EFI_ERROR (Status)) {

+      //

+      // Since we constructed ConfigRequest, failure can only occur if there

+      // is not enough memory. In this case, we point Progress to the first

+      // character of Request.

+      //

+      *Progress = Request;

+    } else {

+      //

+      // In case of success, we point Progress to the null terminator of

+      // Request.

+      //

+      *Progress = Request + StrLen (Request);

+    }

+  }

+

+  if (AllocatedRequest) {

+    FreePool (ConfigRequest);

+  }

+

   return Status;

 }

 

@@ -349,6 +440,21 @@ RouteConfig (
   }

 

   //

+  // Check if <ConfigHdr> matches the GUID and name

+  //

+  *Progress = Configuration;

+  if ((Configuration != NULL) &&

+      !HiiIsConfigHdrMatch (

+         Configuration,

+         &gOvmfPlatformConfigGuid,

+         mVariableName

+         )

+      )

+  {

+    return EFI_NOT_FOUND;

+  }

+

+  //

   // the "read" step in RMW

   //

   Status = PlatformConfigToFormState (&MainFormState);

@@ -867,6 +973,11 @@ PlatformInit (
   }

 

   //

+  // Save the driver image handle.

+  //

+  mImageHandle = ImageHandle;

+

+  //

   // Publish the HII package list to HII Database.

   //

   mInstalledPackages = HiiAddPackages (

diff --git a/OvmfPkg/PlatformDxe/PlatformConfig.c b/OvmfPkg/PlatformDxe/PlatformConfig.c
index e202ac5b47..f5ac2d0609 100644
--- a/OvmfPkg/PlatformDxe/PlatformConfig.c
+++ b/OvmfPkg/PlatformDxe/PlatformConfig.c
@@ -21,7 +21,7 @@
 //

 // Name of the UEFI variable that we use for persistent storage.

 //

-STATIC CHAR16  mVariableName[] = L"PlatformConfig";

+CHAR16  mVariableName[] = L"PlatformConfig";

 

 /**

   Serialize and persistently save platform configuration.

diff --git a/OvmfPkg/PlatformDxe/PlatformConfig.h b/OvmfPkg/PlatformDxe/PlatformConfig.h
index 902c9b2ce0..5d9b457b1b 100644
--- a/OvmfPkg/PlatformDxe/PlatformConfig.h
+++ b/OvmfPkg/PlatformDxe/PlatformConfig.h
@@ -50,4 +50,6 @@ PlatformConfigLoad (
 #define PLATFORM_CONFIG_F_GRAPHICS_RESOLUTION  BIT0

 #define PLATFORM_CONFIG_F_DOWNGRADE            BIT63

 

+extern CHAR16  mVariableName[];

+

 #endif // _PLATFORM_CONFIG_H_