Added NULL/Loopback PDU.

include/loopback.h

@@ -0,0 +1,94 @@
+/*
+ * libtins is a net packet wrapper library for crafting and
+ * interpreting sniffed packets.
+ *
+ * Copyright (C) 2011 Nasel
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef TINS_LOOPBACK_H
+#define TINS_LOOPBACK_H
+
+#include "pdu.h"
+
+namespace Tins {
+class Loopback : public PDU {
+public:
+    /**
+     * This PDU's type.
+     */
+    static const PDU::PDUType pdu_flag = PDU::LOOPBACK;
+
+    /**
+     * \brief Default constructs a Loopback PDU.
+     * 
+     * The family identifier is left as zero.
+     */
+    Loopback();
+
+    /**
+     * \brief Construct a Loopback object.
+     * 
+     * \param family_id The family id to be used.
+     * \param inner_pdu The inner pdu to be set.
+     */
+    Loopback(uint32_t family_id, PDU *inner_pdu = 0);
+    
+    /**
+     * \brief Construct a Loopback object from a buffer.
+     * 
+     * \param buffer The buffer from which this PDU will be constructed.
+     * \param total_sz The total size of the buffer.
+     */
+    Loopback(const uint8_t *buffer, uint32_t total_sz);
+    
+    /**
+     * \brief Getter for the family identifier.
+     * \return The stored family identifier.
+     */
+    uint32_t family() const { return _family; }
+    
+    /**
+     * \brief Setter for the family identifier.
+     * \param family_id The family identifier to be set.
+     */
+    void family(uint32_t family_id);
+    
+    /**
+     * \sa PDU::header_size
+     */
+    uint32_t header_size() const;
+    
+    /**
+     * \brief Getter for the PDU's type.
+     * \sa PDU::pdu_type
+     */
+    PDUType pdu_type() const { return PDU::IP; }
+    
+    /**
+     * \sa PDU::clone
+     */
+    Loopback *clone() const {
+        return new Loopback(*this);
+    }
+private:
+    void write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *parent);
+
+    uint32_t _family;
+};
+}
+
+#endif // TINS_LOOPBACK_H

src/loopback.cpp

@@ -0,0 +1,81 @@
+/*
+ * libtins is a net packet wrapper library for crafting and
+ * interpreting sniffed packets.
+ *
+ * Copyright (C) 2011 Nasel
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef WIN32
+    #include <sys/socket.h>
+#endif
+#include <stdexcept>
+#include <cassert>
+#include "loopback.h"
+#include "packet_sender.h"
+#include "ip.h"
+#include "llc.h"
+#include "rawpdu.h"
+
+namespace Tins {
+Loopback::Loopback()
+: _family()
+{
+    
+}
+    
+Loopback::Loopback(uint32_t family_id, PDU *inner_pdu)
+: PDU(inner_pdu), _family(family_id)
+{
+    
+}
+
+Loopback::Loopback(const uint8_t *buffer, uint32_t total_sz) 
+{
+    if(total_sz < sizeof(_family))
+        throw std::runtime_error("Not enough size for a loopback PDU");
+    _family = *reinterpret_cast<const uint32_t*>(buffer);
+    buffer += sizeof(uint32_t);
+    total_sz -= sizeof(uint32_t);
+    if(total_sz) {
+        switch(_family) {
+            case PF_INET:
+                inner_pdu(new Tins::IP(buffer, total_sz));
+                break;
+            case PF_LLC:
+                inner_pdu(new Tins::LLC(buffer, total_sz));
+                break;
+            default:
+                inner_pdu(new Tins::RawPDU(buffer, total_sz));
+                break;
+        };
+    }
+}
+    
+void Loopback::family(uint32_t family_id) {
+    _family = family_id;
+}
+
+uint32_t Loopback::header_size() const {
+    return sizeof(_family);
+}
+
+void Loopback::write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *) 
+{
+    assert(total_sz >= sizeof(_family));
+    *reinterpret_cast<uint32_t*>(buffer) = _family;
+}
+}