/// <summary>
/// Unwraps a proxy-encoded message for further processing
/// </summary>
/// <param name="mode">Indicates whether the proxy message includes the length prefix or not</param>
/// <returns>Returns the unwrapped message</returns>
public ReadOnlyMemory <byte> UnwrapMessage(out KdcProxyMessageMode mode)
{
var prefix = this.KerbMessage.Slice(0, 4).AsLong();
var message = this.KerbMessage;
if (prefix != this.KerbMessage.Length - 4)
{
var possibleMessageType = KrbMessage.DetectMessageType(this.KerbMessage);
if (!possibleMessageType.IsValidMessageType())
{
throw new InvalidOperationException(
$"Proxy message length {prefix} doesn't match actual message length {message.Length}"
);
}
mode = KdcProxyMessageMode.NoPrefix;
}
else
{
message = this.KerbMessage.Slice(4);
mode = KdcProxyMessageMode.IncludeLengthPrefix;
}
return(message);
}
/// <summary>
/// Wraps a standard KDC message into a proxy message
/// </summary>
/// <param name="message">The message to wrap</param>
/// <param name="domain">The optional domain hint for downstream processing</param>
/// <param name="hint">A DC location hint for downstream processing</param>
/// <param name="mode">The encoding mode which indicates whether the message should include the length prefix or not</param>
/// <returns>Returns a formed KDC Message</returns>
public static KdcProxyMessage WrapMessage(
ReadOnlyMemory <byte> message,
string domain = null,
DcLocatorHint?hint = null,
KdcProxyMessageMode mode = KdcProxyMessageMode.IncludeLengthPrefix
)
{
var proxyMessage = new KdcProxyMessage()
{
TargetDomain = domain,
DcLocatorHint = hint
};
if (mode == KdcProxyMessageMode.NoPrefix)
{
proxyMessage.KerbMessage = message;
}
else
{
proxyMessage.KerbMessage = Tcp.FormatKerberosMessageStream(message);
}
return(proxyMessage);
}
private static ReadOnlyMemory <byte> EncodeProxyResponse(ReadOnlyMemory <byte> response, KdcProxyMessageMode mode)
{
return(KdcProxyMessage.WrapMessage(response, mode: mode).Encode());
}