/// <summary>
/// Performs an encryption or decryption operation.
/// </summary>
/// <param name="cipherFunction">The delegate that will actually perform the cryptographic operation.</param>
/// <returns>A buffer containing the result of the cryptographic operation.</returns>
protected unsafe byte[] EncryptOrDecrypt(EncryptOrDecryptFunction cipherFunction)
{
Requires.NotNull(cipherFunction, nameof(cipherFunction));
if (this.EncryptionPadding.Value == AsymmetricEncryptionPadding.None)
{
return(cipherFunction(null, NCryptEncryptFlags.NCRYPT_NO_PADDING_FLAG));
}
switch (this.EncryptionPadding.Value)
{
case AsymmetricEncryptionPadding.Pkcs1:
return(cipherFunction(null, NCryptEncryptFlags.NCRYPT_PAD_PKCS1_FLAG));
case AsymmetricEncryptionPadding.Oaep:
fixed(char *hashAlgorithmNamePointer = &HashAlgorithmProviderFactory.GetHashAlgorithmName(this.SignatureHash.Value).ToCharArrayWithNullTerminator()[0])
{
var paddingInfo = new BCrypt.BCRYPT_OAEP_PADDING_INFO
{
pszAlgId = hashAlgorithmNamePointer,
pbLabel = null,
cbLabel = 0,
};
return(cipherFunction(&paddingInfo, NCryptEncryptFlags.NCRYPT_PAD_OAEP_FLAG));
}
default:
throw new NotImplementedException();
}
}
public static byte[] Decrypt(byte[] cipherText, CngKey key, CngAlgorithm hash)
{
uint num;
BCrypt.BCRYPT_OAEP_PADDING_INFO bCRYPTOAEPPADDINGINFO = new BCrypt.BCRYPT_OAEP_PADDING_INFO(hash.Algorithm);
uint num1 = NCrypt.NCryptDecrypt(key.Handle, cipherText, (int)cipherText.Length, ref bCRYPTOAEPPADDINGINFO, null, 0, out num, 4);
if (num1 != 0)
{
throw new CryptographicException(string.Format("NCrypt.Decrypt() (plaintext buffer size) failed with status code:{0}", num1));
}
byte[] numArray = new byte[num];
num1 = NCrypt.NCryptDecrypt(key.Handle, cipherText, (int)cipherText.Length, ref bCRYPTOAEPPADDINGINFO, numArray, num, out num, 4);
if (num1 != 0)
{
throw new CryptographicException(string.Format("NCrypt.Decrypt() failed with status code:{0}", num1));
}
return(numArray);
}
public static byte[] Decrypt(byte[] cipherText, CngKey key, CngAlgorithm hash)
{
var paddingInfo = new BCrypt.BCRYPT_OAEP_PADDING_INFO(hash.Algorithm);
uint plainTextByteSize;
uint status = NCrypt.NCryptDecrypt(key.Handle, cipherText, cipherText.Length, ref paddingInfo, null, 0, out plainTextByteSize, BCrypt.BCRYPT_PAD_OAEP);
if (status != BCrypt.ERROR_SUCCESS)
{
throw new CryptographicException(string.Format("NCrypt.Decrypt() (plaintext buffer size) failed with status code:{0}", status));
}
var plainText = new byte[plainTextByteSize];
status = NCrypt.NCryptDecrypt(key.Handle, cipherText, cipherText.Length, ref paddingInfo, plainText, plainTextByteSize, out plainTextByteSize, BCrypt.BCRYPT_PAD_OAEP);
if (status != BCrypt.ERROR_SUCCESS)
{
throw new CryptographicException(string.Format("NCrypt.Decrypt() failed with status code:{0}", status));
}
return(plainText);
}
