PFND3D11_1DDI_DECRYPTIONBLT callback function

Writes encrypted data to a protected surface. This function is called only if D3D11_1DDI_CONTENT_PROTECTION_CAPS_DECRYPTION_BLT is set in the Caps member of the D3D11_1DDI_VIDEO_CONTENT_PROTECTION_CAPS structure.



VOID APIENTRY* DecryptionBlt(
  _In_       D3D10DDI_HDEVICE                hDevice,
  _In_       D3D11_1DDI_HCRYPTOSESSION       hCryptoSession,
  _In_       D3D10DDI_HRESOURCE              hSrcResource,
  _In_       D3D10DDI_HRESOURCE              hDstResource,
  _In_ const D3D11_1DDI_ENCRYPTED_BLOCK_INFO *pEncryptedBlockInfo,
  _In_       UINT                            ContentKeySize,
  _In_ const VOID                            *pContentKey,
  _In_       UINT                            IVSize,
  _In_ const VOID                            *pIV
{ ... }


hDevice [in]

A handle to the display device (graphics context).

hCryptoSession [in]

A handle to the driver's private data for the cryptographic session. This handle was created by the Direct3D runtime and passed to the driver in the call to the CreateCryptoSession function.

hSrcResource [in]

A handle to the resource that contains the source data.

hDstResource [in]

A pointer to the resource where the encrypted data is to be written.

pEncryptedBlockInfo [in]

A pointer to a D3D11_1DDI_ENCRYPTED_BLOCK_INFO structure that describes the portions of the buffer that are encrypted.

Note  If the entire buffer is encrypted, pEncryptedBlockinfo should be set to NULL.
ContentKeySize [in]

The size, in bytes, of the content key.

pContentKey [in]

A pointer to a block of memory that contains the content key that is required to decrypt the bit-block transfer (bitblt) data.

If pContentKey is not set to NULL, the buffer data is encrypted by using the specified content key. The data for this key is encrypted by using the session key with the AES-ECB algorithm.

If pContentKey is NULL, the graphics adapter does not require a separate content key to decrypt the data. In this case, the session key is used to decrypt the data.

IVSize [in]

The size, in bytes, of the initialization vector (IV).

pIV [in]

A pointer to a block of memory that contains the initialization vector that is required to decrypt the bitblt data. For more information, see the Remarks section.


If pIV is NULL, the graphics adapter does not require a separate initialization vector to decrypt the data. That is, the session key is used to decrypt the data.


Return value

This callback function does not return a value.


For 128-bit AES-CTR encryption, the pIV parameter points to a D3D11_1DDI_AES_CTR_IV structure that is allocated by the application. However, the actual contents of this structure are filled in by the driver or graphics adapter. When the first IV is generated, the driver or adapter initializes the IV member of this structure to a random number. For each subsequent IV, the caller increments the IV member, ensuring that the value always increases. This procedure enables the application to validate that the same IV is never used more than once with the same key pair.

For other encryption types, a different structure might be used, or the encryption might not use an IV.

Note  This function does not honor a Direct3D version 11 predicate that may have been set.


Minimum supported client

Windows 8

Minimum supported server

Windows Server 2012

Target platform


D3d10umddi.h (include D3d10umddi.h)

See also




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