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RtlDecryptMemory function

[The RtlDecryptMemory function is available for use in the operating systems specified in the Requirements section. It may be altered or unavailable in subsequent versions. Instead, use the CryptUnprotectMemory function.]

Applies to: desktop apps only

The RtlDecryptMemory function decrypts memory contents previously encrypted by the RtlEncryptMemory function.

Note This function has no associated import library. This function is available as a resource named SystemFunction041 in Advapi32.dll. You must use the LoadLibrary and GetProcAddress functions to dynamically link to Advapi32.dll.

Syntax

Copy

NTSTATUS RtlDecryptMemory(
  __inout  PVOID Memory,
  __in     ULONG MemoryLength,
  __in     ULONG OptionFlags
);

Parameters

Memory [in, out]

A pointer to the memory to encrypt. The size of the memory must be a multiple of the RTL_ENCRYPT_MEMORY_SIZE constant.

MemoryLength [in]

Number of bytes to which Memory points. The number of bytes must be a multiple of the RTL_ENCRYPT_MEMORY_SIZE constant.

OptionFlags [in]

Value that specifies how the encryption works over process boundaries and impersonation. This parameter can be one of the following values. The values are mutually exclusive. You must specify the same flag when encrypting and decrypting the memory.

Value	Meaning
0	Encrypt and decrypt memory in the same process. An application running in a different process will not be able to decrypt the data.
RTL_ENCRYPT_OPTION_CROSS_PROCESS	Encrypt and decrypt memory in different processes. An application running in a different process will be able to decrypt the data.
RTL_ENCRYPT_OPTION_SAME_LOGON	Use the same logon credentials to encrypt and decrypt memory in different processes. An application running in a different process will be able to decrypt the data. However, the process must run as the same user that encrypted the data and in the same logon session.

Return value

If the function is successful, the return value is STATUS_SUCCESS.

If the function fails, the return value is an NTSTATUS code that indicates the error.

Requirements

Minimum supported client	Windows XP, Windows 2000 Professional with SP3
Minimum supported server	Windows Server 2003, Windows 2000 Server with SP3
Header	Ntsecapi.h
DLL	Advapi32.dll

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Build date: 3/6/2012

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C# syntax

[DllImport("advapi32.dll", CharSet=CharSet.Unicode, SetLastError=true)]
internal static extern int SystemFunction041([In, Out] byte[] pDataIn, [In] uint cbDataIn, [In] uint dwFlags);

History

5/6/2009
dmex

vb.net syntax

<DllImport("advapi32.dll", CharSet:=CharSet.Unicode, SetLastError:=True)> _
Public Shared Function SystemFunction041(<[In], Out> ByVal pDataIn As Byte(), <[In]> ByVal cbDataIn As UInt32, <[In]> ByVal dwFlags As UInt32) As Integer
End Function

History

5/6/2009
dmex