Re: [PATCH 3/6] NetworkPkg/TlsAuthConfigDxe: replace OpenFileByDevicePath() with UefiLib API

[Laszlo Ersek <lersek@redhat.com>]

On 07/18/18 22:50, Laszlo Ersek wrote:
> Replace the OpenFileByDevicePath() function with EfiOpenFileByDevicePath()
> from UefiLib, correcting the following issues:
> 
> - imprecise comments on OpenFileByDevicePath(),
> - code duplication between this module and other modules,
> - local variable name "EfiSimpleFileSystemProtocol" starting with "Efi"
>   prefix,
> - bogus "FileHandle = NULL" assignments,
> - passing a potentially unaligned "FILEPATH_DEVICE_PATH.PathName" field to
>   a protocol member function (forbidden by the UEFI spec),
> - leaking "Handle1" when the device path type/subtype check fails in the
>   loop,
> - stale SHELL_FILE_HANDLE reference in a comment.
> 
> Cc: Jiaxin Wu <jiaxin.wu@intel.com>
> Cc: Siyuan Fu <siyuan.fu@intel.com>
> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1008
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
> ---
>  NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigDxe.inf |   1 -
>  NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c  | 141 +-------------------
>  2 files changed, 1 insertion(+), 141 deletions(-)

Jiaxin, Siyuan, do you guys have comments on this patch?

Thanks,
Laszlo

> 
> diff --git a/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigDxe.inf b/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigDxe.inf
> index 3cfcdb9983f1..e5face7b4de5 100644
> --- a/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigDxe.inf
> +++ b/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigDxe.inf
> @@ -57,7 +57,6 @@ [LibraryClasses]
>  [Protocols]
>    gEfiDevicePathProtocolGuid                    ## PRODUCES
>    gEfiHiiConfigAccessProtocolGuid               ## PRODUCES
> -  gEfiSimpleFileSystemProtocolGuid              ## SOMETIMES_CONSUMES
>  
>  [Guids]
>    gTlsAuthConfigGuid                            ## PRODUCES  ## GUID
> diff --git a/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c b/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c
> index 31450b3e4a1b..7259c5e82f61 100644
> --- a/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c
> +++ b/NetworkPkg/TlsAuthConfigDxe/TlsAuthConfigImpl.c
> @@ -574,145 +574,6 @@ ON_EXIT:
>    return Status;
>  }
>  
> -/**
> -  This function will open a file or directory referenced by DevicePath.
> -
> -  This function opens a file with the open mode according to the file path. The
> -  Attributes is valid only for EFI_FILE_MODE_CREATE.
> -
> -  @param[in, out]  FilePath        On input, the device path to the file.
> -                                   On output, the remaining device path.
> -  @param[out]      FileHandle      Pointer to the file handle.
> -  @param[in]       OpenMode        The mode to open the file with.
> -  @param[in]       Attributes      The file's file attributes.
> -
> -  @retval EFI_SUCCESS              The information was set.
> -  @retval EFI_INVALID_PARAMETER    One of the parameters has an invalid value.
> -  @retval EFI_UNSUPPORTED          Could not open the file path.
> -  @retval EFI_NOT_FOUND            The specified file could not be found on the
> -                                   device or the file system could not be found on
> -                                   the device.
> -  @retval EFI_NO_MEDIA             The device has no medium.
> -  @retval EFI_MEDIA_CHANGED        The device has a different medium in it or the
> -                                   medium is no longer supported.
> -  @retval EFI_DEVICE_ERROR         The device reported an error.
> -  @retval EFI_VOLUME_CORRUPTED     The file system structures are corrupted.
> -  @retval EFI_WRITE_PROTECTED      The file or medium is write protected.
> -  @retval EFI_ACCESS_DENIED        The file was opened read only.
> -  @retval EFI_OUT_OF_RESOURCES     Not enough resources were available to open the
> -                                   file.
> -  @retval EFI_VOLUME_FULL          The volume is full.
> -**/
> -EFI_STATUS
> -EFIAPI
> -OpenFileByDevicePath (
> -  IN OUT EFI_DEVICE_PATH_PROTOCOL     **FilePath,
> -  OUT EFI_FILE_HANDLE                 *FileHandle,
> -  IN UINT64                           OpenMode,
> -  IN UINT64                           Attributes
> -  )
> -{
> -  EFI_STATUS                      Status;
> -  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *EfiSimpleFileSystemProtocol;
> -  EFI_FILE_PROTOCOL               *Handle1;
> -  EFI_FILE_PROTOCOL               *Handle2;
> -  EFI_HANDLE                      DeviceHandle;
> -
> -  if ((FilePath == NULL || FileHandle == NULL)) {
> -    return EFI_INVALID_PARAMETER;
> -  }
> -
> -  Status = gBS->LocateDevicePath (
> -                  &gEfiSimpleFileSystemProtocolGuid,
> -                  FilePath,
> -                  &DeviceHandle
> -                  );
> -  if (EFI_ERROR (Status)) {
> -    return Status;
> -  }
> -
> -  Status = gBS->OpenProtocol(
> -                  DeviceHandle,
> -                  &gEfiSimpleFileSystemProtocolGuid,
> -                  (VOID**)&EfiSimpleFileSystemProtocol,
> -                  gImageHandle,
> -                  NULL,
> -                  EFI_OPEN_PROTOCOL_GET_PROTOCOL
> -                  );
> -  if (EFI_ERROR (Status)) {
> -    return Status;
> -  }
> -
> -  Status = EfiSimpleFileSystemProtocol->OpenVolume(EfiSimpleFileSystemProtocol, &Handle1);
> -  if (EFI_ERROR (Status)) {
> -    FileHandle = NULL;
> -    return Status;
> -  }
> -
> -  //
> -  // go down directories one node at a time.
> -  //
> -  while (!IsDevicePathEnd (*FilePath)) {
> -    //
> -    // For file system access each node should be a file path component
> -    //
> -    if (DevicePathType    (*FilePath) != MEDIA_DEVICE_PATH ||
> -        DevicePathSubType (*FilePath) != MEDIA_FILEPATH_DP
> -       ) {
> -      FileHandle = NULL;
> -      return (EFI_INVALID_PARAMETER);
> -    }
> -    //
> -    // Open this file path node
> -    //
> -    Handle2  = Handle1;
> -    Handle1 = NULL;
> -
> -    //
> -    // Try to test opening an existing file
> -    //
> -    Status = Handle2->Open (
> -                        Handle2,
> -                        &Handle1,
> -                        ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,
> -                        OpenMode &~EFI_FILE_MODE_CREATE,
> -                        0
> -                        );
> -
> -    //
> -    // see if the error was that it needs to be created
> -    //
> -    if ((EFI_ERROR (Status)) && (OpenMode != (OpenMode &~EFI_FILE_MODE_CREATE))) {
> -      Status = Handle2->Open (
> -                          Handle2,
> -                          &Handle1,
> -                          ((FILEPATH_DEVICE_PATH*)*FilePath)->PathName,
> -                          OpenMode,
> -                          Attributes
> -                          );
> -    }
> -    //
> -    // Close the last node
> -    //
> -    Handle2->Close (Handle2);
> -
> -    if (EFI_ERROR(Status)) {
> -      return (Status);
> -    }
> -
> -    //
> -    // Get the next node
> -    //
> -    *FilePath = NextDevicePathNode (*FilePath);
> -  }
> -
> -  //
> -  // This is a weak spot since if the undefined SHELL_FILE_HANDLE format changes this must change also!
> -  //
> -  *FileHandle = (VOID*)Handle1;
> -  return EFI_SUCCESS;
> -}
> -
>  /**
>    This function converts an input device structure to a Unicode string.
>  
> @@ -1039,7 +900,7 @@ UpdatePage(
>  
>    mTlsAuthPrivateData->FileContext->FileName = FileName;
>  
> -  OpenFileByDevicePath (
> +  EfiOpenFileByDevicePath (
>      &FilePath,
>      &mTlsAuthPrivateData->FileContext->FHandle,
>      EFI_FILE_MODE_READ,
>