AsymmetricKeyExchangeDeformatter.DecryptKeyExchange(Byte[]) Method

Definition

When overridden in a derived class, extracts secret information from the encrypted key exchange data.

public:
 abstract cli::array <System::Byte> ^ DecryptKeyExchange(cli::array <System::Byte> ^ rgb);
public abstract byte[] DecryptKeyExchange (byte[] rgb);
abstract member DecryptKeyExchange : byte[] -> byte[]
Public MustOverride Function DecryptKeyExchange (rgb As Byte()) As Byte()

Parameters

rgb
Byte[]

The key exchange data within which the secret information is hidden.

Returns

Byte[]

The secret information derived from the key exchange data.

Examples

The following code example demonstrates how to override the DecryptKeyExchange method to create an encrypted key exchange for the specified input data. This code example is part of a larger example provided for the AsymmetricKeyExchangeDeformatter class.

// Create the encrypted key exchange data from the specified input
// data. This method uses the RSA class only. To
// support additional providers or provide custom decryption logic,
// add logic to this member.
public override byte[] DecryptKeyExchange(byte[] rgbData)
{
    byte[] decryptedBytes = null;

    if (_rsaKey != null)
    {
        if (_rsaKey is RSA rsa)
        {
            decryptedBytes = rsa.Decrypt(rgbData, RSAEncryptionPadding.OaepSHA1);
        }
        // Add custom decryption logic here.
    }
    else
    {
        throw new CryptographicUnexpectedOperationException(
            "Cryptography_MissingKey");
    }

    return decryptedBytes;
}
' Create the encrypted key exchange data from the specified input
' data. This method uses the RSA class only. To
' support additional providers or provide custom decryption logic,
' add logic to this member.
Public Overrides Function DecryptKeyExchange(
    ByVal rgbData() As Byte) As Byte()

    Dim decryptedBytes() As Byte

    If (Not rsaKey Is Nothing) Then
        If (TypeOf (rsaKey) Is RSA) Then
            Dim rsa As RSA
            rsa = CType(rsaKey, RSA)

            decryptedBytes = rsa.Decrypt(rgbData, RSAEncryptionPadding.OaepSHA1)
        End If

        ' Add custom decryption logic here.

    Else
        Throw New CryptographicUnexpectedOperationException(
            "Cryptography_MissingKey")
    End If

    Return decryptedBytes
End Function

Remarks

You must specify a key before calling an implementation of this method.

Applies to

See also