/// <summary>
/// Decrypts a key using the specified algorithm.
/// </summary>
/// <param name="algorithm">Algorithm to use when decrypting the key.</param>
/// <param name="keyData">Bytes representing the encrypted key.</param>
/// <returns>Decrypted bytes.</returns>
public override byte[] DecryptKey(string algorithm, byte[] keyData)
{
if (_securityKey == null)
{
ResolveKey();
}
return(_securityKey.DecryptKey(algorithm, keyData));
}
/// <summary>
/// Resolves the given SecurityKeyIdentifierClause to a SecurityKey.
/// </summary>
/// <param name="keyIdentifierClause">SecurityKeyIdentifierClause to resolve</param>
/// <param name="key">The resolved SecurityKey.</param>
/// <returns>True if successfully resolved.</returns>
/// <exception cref="ArgumentNullException">The input argument 'keyIdentifierClause' is null.</exception>
protected override bool TryResolveSecurityKeyCore(SecurityKeyIdentifierClause keyIdentifierClause, out SecurityKey key)
{
if (keyIdentifierClause == null)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperArgumentNull("keyIdentifierClause");
}
key = null;
EncryptedKeyIdentifierClause encryptedKeyIdentifierClause = keyIdentifierClause as EncryptedKeyIdentifierClause;
if (encryptedKeyIdentifierClause != null)
{
SecurityKeyIdentifier keyIdentifier = encryptedKeyIdentifierClause.EncryptingKeyIdentifier;
if (keyIdentifier != null && keyIdentifier.Count > 0)
{
for (int i = 0; i < keyIdentifier.Count; i++)
{
SecurityKey unwrappingSecurityKey = null;
if (TryResolveSecurityKey(keyIdentifier[i], out unwrappingSecurityKey))
{
byte[] wrappedKey = encryptedKeyIdentifierClause.GetEncryptedKey();
string wrappingAlgorithm = encryptedKeyIdentifierClause.EncryptionMethod;
byte[] unwrappedKey = unwrappingSecurityKey.DecryptKey(wrappingAlgorithm, wrappedKey);
key = new InMemorySymmetricSecurityKey(unwrappedKey, false);
return(true);
}
}
}
}
else
{
SecurityToken token = null;
if (TryResolveToken(keyIdentifierClause, out token))
{
if (token.SecurityKeys.Count > 0)
{
key = token.SecurityKeys[0];
return(true);
}
}
}
return(false);
}
