From d6ced92a804dc434fc50e57ad759d0ebf731cc4a Mon Sep 17 00:00:00 2001
From: Geoffrey Merck <F4FXL@users.noreply.github.com>
Date: Thu, 30 Dec 2021 13:45:02 +0100
Subject: [PATCH] Add nattrversal handler

---
 NatTraversalHandler.cpp | 61 +++++++++++++++++++++++++++++++
 NatTraversalHandler.h   | 80 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 141 insertions(+)
 create mode 100644 NatTraversalHandler.cpp
 create mode 100644 NatTraversalHandler.h

diff --git a/NatTraversalHandler.cpp b/NatTraversalHandler.cpp
new file mode 100644
index 0000000..8ee9ac0
--- /dev/null
+++ b/NatTraversalHandler.cpp
@@ -0,0 +1,61 @@
+/*
+ *   Copyright (C) 2010,2011,2012,2013,2014,2015,2016,2017,2018 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if defined(ENABLE_NAT_TRAVERSAL)
+
+#include "NatTraversalHandler.h"
+
+const unsigned int CACHE_SIZE = 500U;
+
+CNatTraversalHandler::CNatTraversalHandler() :
+m_g2cache(CACHE_SIZE),
+m_g2Handler(NULL)
+{
+
+}
+
+CNatTraversalHandler::~CNatTraversalHandler()
+{
+    for (CNatTraversalCache_t::iterator it = m_g2cache.begin(); it != m_g2cache.end(); ++it)
+		delete it->second;
+}
+
+void CNatTraversalHandler::setG2Handler(CG2ProtocolHandler * handler)
+{
+    m_g2Handler = handler;
+}
+
+void CNatTraversalHandler::traverseNatG2(const wxString& address)
+{
+    if(m_g2Handler != NULL){
+        CNatTraversalRecord* record = m_g2cache[address];
+        
+        if(record == NULL) {
+            record = new CNatTraversalRecord(address);
+            m_g2cache[address] = record;
+        }
+
+        std::time_t currentTime = std::time(NULL);
+        if(currentTime - record->getTimestamp() > G2_TRAVERSAL_TIMEOUT) {
+            record->setTimestamp(currentTime);
+            m_g2Handler->traverseNat(address);
+        }
+    }
+}
+
+#endif
\ No newline at end of file
diff --git a/NatTraversalHandler.h b/NatTraversalHandler.h
new file mode 100644
index 0000000..0069fea
--- /dev/null
+++ b/NatTraversalHandler.h
@@ -0,0 +1,80 @@
+/*
+ *   Copyright (C) 2010,2011,2012,2013,2014,2015,2016,2017,2018 by Jonathan Naylor G4KLX
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#if defined(ENABLE_NAT_TRAVERSAL)
+#ifndef NatTraversalHandler_H
+#define NatTraversalHandler_H
+
+#define G2_TRAVERSAL_TIMEOUT 29 //seconds
+
+#include "G2ProtocolHandler.h"
+
+#include <wx/wx.h>
+#include <ctime>
+
+enum NAT_TRAVERSAL_TYPE {
+    NTT_G2,
+    //NTT_DEXTRA
+    //NTT_DCS
+    //NTT_DPLUS
+};
+
+class CNatTraversalRecord {
+public:
+    CNatTraversalRecord(const wxString& address) :
+    m_address(address),
+    m_timestamp(0)
+    {
+    }
+
+    std::time_t getTimestamp() const
+    {
+        return m_timestamp;
+    }
+
+    void setTimestamp(std::time_t timestamp)
+    {
+        m_timestamp = timestamp;
+    }
+
+private:
+    wxString m_address;
+    std::time_t m_timestamp;
+};
+
+WX_DECLARE_STRING_HASH_MAP(CNatTraversalRecord*, CNatTraversalCache_t);
+
+/*
+* This keeps track of when we UDP punched to one destination so to avoid unnecessary traffic on each ircddb reporting
+*/
+class CNatTraversalHandler {
+public:
+    CNatTraversalHandler();
+    ~CNatTraversalHandler();
+
+    void setG2Handler(CG2ProtocolHandler* handler);
+    void traverseNatG2(const wxString& address);
+
+private:
+    CNatTraversalCache_t m_g2cache;    
+    CG2ProtocolHandler* m_g2Handler;
+};
+
+#endif
+
+#endif
\ No newline at end of file