public static async Task <StunMessage> Parse(Stream stream)
{
var header = new byte[20];
await stream.ReadAsync(header, 0, 20);
MessageMethod method = ParseMethod(header[0], header[1]);
MessageClass @class = ParseClass(header[0], header[1]);
var length = new byte[2];
System.Array.Copy(header, 2, length, 0, 2);
var transactionId = new byte[12];
System.Array.Copy(header, 8, transactionId, 0, 12);
var body = new byte[length.ToUShort()];
await stream.ReadAsync(body, 0, body.Length);
IEnumerable <Attribute> attributes = ParseAttributes(
body,
transactionId
);
StunMessage rv = null;
switch (@class)
{
case MessageClass.SuccessResponse:
switch (method)
{
case MessageMethod.Allocate:
rv = new AllocateSuccessResponse();
break;
case MessageMethod.Connect:
rv = new ConnectSuccessResponse();
break;
case MessageMethod.ConnectionBind:
rv = new ConnectionBindSuccessResponse();
break;
case MessageMethod.Binding:
rv = new BindingSuccessResponse();
break;
case MessageMethod.CreatePermission:
rv = new CreatePermissionSuccessResponse();
break;
case MessageMethod.Refresh:
rv = new RefreshSuccessResponse();
break;
}
break;
case MessageClass.ErrorResponse:
switch (method)
{
case MessageMethod.Allocate:
rv = new AllocateErrorResponse();
break;
case MessageMethod.CreatePermission:
rv = new CreatePermissionErrorResponse();
break;
case MessageMethod.Refresh:
rv = new RefreshErrorResponse();
break;
}
break;
case MessageClass.Indication:
switch (method)
{
case MessageMethod.ConnectionAttempt:
rv = new ConnectionAttempt();
break;
}
break;
}
if (rv != null)
{
rv.TransactionId = transactionId;
rv.Attributes = attributes;
}
return(rv);
}
