First approximation of CCNx protocol stack
diff --git a/model/ccnx-l4-protocol.h b/model/ccnx-l4-protocol.h
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+// -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*-
+//
+// Copyright (c) 2006 Georgia Tech Research Corporation
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License version 2 as
+// published by the Free Software Foundation;
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+//
+// Author:
+//
+
+#ifndef CCNX_L4_PROTOCOL_H
+#define CCNX_L4_PROTOCOL_H
+
+#include "ns3/object.h"
+#include "ns3/callback.h"
+#include "ns3/ccnx-interest-header.h"
+#include "ns3/ccnx-content-object-header.h"
+
+namespace ns3 {
+
+class Packet;
+class CcnxInterface;
+class CcnxRoute;
+
+/**
+ * \brief Actual implementation of CCNx protocol
+ */
+class CcnxL4Protocol : public Object
+{
+public:
+ enum RxStatus {
+ RX_OK,
+
+ // RX_CSUM_FAILED,
+ // RX_ENDPOINT_CLOSED,
+ // RX_ENDPOINT_UNREACH
+ };
+
+ static TypeId GetTypeId (void);
+
+ virtual ~CcnxL4Protocol ();
+
+ /**
+ * \param p packet to forward up
+ * \param header Ccnx Header information
+ * \param incomingInterface the CcnxInterface on which the packet arrived
+ *
+ * Called from lower-level layers to send the packet up
+ * in the stack.
+ */
+ virtual enum RxStatus Receive (Ptr<Packet> p,
+ CcnxHeader const &header,
+ Ptr<CcnxInterface> incomingInterface) = 0;
+
+ typedef Callback<void,Ptr<Packet>, Ptr<CcnxRoute> > DownTargetCallback;
+ /**
+ * This method allows a caller to set the current down target callback
+ * set for this L4 protocol
+ *
+ * \param cb current Callback for the L4 protocol
+ */
+ virtual void SetDownTarget (DownTargetCallback cb) = 0;
+ /**
+ * This method allows a caller to get the current down target callback
+ * set for this L4 protocol, for
+ *
+ * \return current Callback for the L4 protocol
+ */
+ virtual DownTargetCallback GetDownTarget (void) const = 0;
+};
+
+} // Namespace ns3
+
+#endif // CCNX_L4_PROTOCOL_H