private static void InitPrompt(ref DPAPI.CRYPTPROTECT_PROMPTSTRUCT ps)
{
ps.cbSize = Marshal.SizeOf(typeof(DPAPI.CRYPTPROTECT_PROMPTSTRUCT));
ps.dwPromptFlags = 0;
ps.hwndApp = DPAPI.NullPtr;
ps.szPrompt = null;
}
public static byte[] Decrypt(byte[] cipherTextBytes, byte[] entropyBytes, out string description)
{
DPAPI.DATA_BLOB dATA_BLOB = default(DPAPI.DATA_BLOB);
DPAPI.DATA_BLOB dATA_BLOB2 = default(DPAPI.DATA_BLOB);
DPAPI.DATA_BLOB dATA_BLOB3 = default(DPAPI.DATA_BLOB);
DPAPI.CRYPTPROTECT_PROMPTSTRUCT cRYPTPROTECT_PROMPTSTRUCT = default(DPAPI.CRYPTPROTECT_PROMPTSTRUCT);
DPAPI.InitPrompt(ref cRYPTPROTECT_PROMPTSTRUCT);
description = string.Empty;
byte[] result;
try
{
try
{
DPAPI.InitBLOB(cipherTextBytes, ref dATA_BLOB2);
}
catch (Exception innerException)
{
throw new Exception("Cannot initialize ciphertext BLOB.", innerException);
}
try
{
DPAPI.InitBLOB(entropyBytes, ref dATA_BLOB3);
}
catch (Exception innerException2)
{
throw new Exception("Cannot initialize entropy BLOB.", innerException2);
}
int dwFlags = 1;
if (!DPAPI.CryptUnprotectData(ref dATA_BLOB2, ref description, ref dATA_BLOB3, IntPtr.Zero, ref cRYPTPROTECT_PROMPTSTRUCT, dwFlags, ref dATA_BLOB))
{
Marshal.GetLastWin32Error();
}
byte[] array = new byte[dATA_BLOB.cbData];
Marshal.Copy(dATA_BLOB.pbData, array, 0, dATA_BLOB.cbData);
result = array;
}
catch (Exception innerException3)
{
throw new Exception("DPAPI was unable to decrypt data.", innerException3);
}
finally
{
if (dATA_BLOB.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB.pbData);
}
if (dATA_BLOB2.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB2.pbData);
}
if (dATA_BLOB3.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB3.pbData);
}
}
return(result);
}
public static byte[] Encrypt(DPAPI.KeyType keyType, byte[] plainTextBytes, byte[] entropyBytes, string description)
{
if (plainTextBytes == null)
{
plainTextBytes = new byte[0];
}
if (entropyBytes == null)
{
entropyBytes = new byte[0];
}
if (description == null)
{
description = string.Empty;
}
DPAPI.DATA_BLOB dATA_BLOB = default(DPAPI.DATA_BLOB);
DPAPI.DATA_BLOB dATA_BLOB2 = default(DPAPI.DATA_BLOB);
DPAPI.DATA_BLOB dATA_BLOB3 = default(DPAPI.DATA_BLOB);
DPAPI.CRYPTPROTECT_PROMPTSTRUCT cRYPTPROTECT_PROMPTSTRUCT = default(DPAPI.CRYPTPROTECT_PROMPTSTRUCT);
DPAPI.InitPrompt(ref cRYPTPROTECT_PROMPTSTRUCT);
byte[] result;
try
{
try
{
DPAPI.InitBLOB(plainTextBytes, ref dATA_BLOB);
}
catch (Exception innerException)
{
throw new Exception("Cannot initialize plaintext BLOB.", innerException);
}
try
{
DPAPI.InitBLOB(entropyBytes, ref dATA_BLOB3);
}
catch (Exception innerException2)
{
throw new Exception("Cannot initialize entropy BLOB.", innerException2);
}
int num = 1;
if (keyType == DPAPI.KeyType.MachineKey)
{
num |= 4;
}
if (!DPAPI.CryptProtectData(ref dATA_BLOB, description, ref dATA_BLOB3, IntPtr.Zero, ref cRYPTPROTECT_PROMPTSTRUCT, num, ref dATA_BLOB2))
{
Marshal.GetLastWin32Error();
}
byte[] array = new byte[dATA_BLOB2.cbData];
Marshal.Copy(dATA_BLOB2.pbData, array, 0, dATA_BLOB2.cbData);
result = array;
}
catch (Exception innerException3)
{
throw new Exception("DPAPI was unable to encrypt data.", innerException3);
}
finally
{
if (dATA_BLOB.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB.pbData);
}
if (dATA_BLOB2.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB2.pbData);
}
if (dATA_BLOB3.pbData != IntPtr.Zero)
{
Marshal.FreeHGlobal(dATA_BLOB3.pbData);
}
}
return(result);
}
private static extern bool CryptUnprotectData(ref DPAPI.DATA_BLOB pCipherText, ref string pszDescription, ref DPAPI.DATA_BLOB pEntropy, IntPtr pReserved, ref DPAPI.CRYPTPROTECT_PROMPTSTRUCT pPrompt, int dwFlags, ref DPAPI.DATA_BLOB pPlainText);
