Allow other processes to bind to the STUN UDP port. (#20)

* allow multiple port binds for UDP

* adding --reuseaddr command line switch for setting the SO_REUSEADDR option

* initializing fReuseAddr and modifying help page

client/clientmain.cpp

@@ -506,7 +506,7 @@ HRESULT UdpClientLoop(StunClientLogicConfig& config, const ClientSocketConfig& s
         Chk(hr);
     }
 
-    hr = stunSocket.UDPInit(socketconfig.addrLocal, RolePP);
+    hr = stunSocket.UDPInit(socketconfig.addrLocal, RolePP, false);
     if (FAILED(hr))
     {
         Logging::LogMsg(LL_ALWAYS, "Unable to create local socket: (error = x%x)", hr);

networkutils/stunsocket.cpp

@@ -319,9 +319,9 @@ Cleanup:
 
 
 
-HRESULT CStunSocket::UDPInit(const CSocketAddress& local, SocketRole role)
+HRESULT CStunSocket::UDPInit(const CSocketAddress& local, SocketRole role, bool fSetReuseFlag)
 {
-    return InitCommon(SOCK_DGRAM, local, role, false);
+    return InitCommon(SOCK_DGRAM, local, role, fSetReuseFlag);
 }
 
 HRESULT CStunSocket::TCPInit(const CSocketAddress& local, SocketRole role, bool fSetReuseFlag)

networkutils/stunsocket.h

@@ -65,7 +65,7 @@ public:
     
     void UpdateAddresses();
     
-    HRESULT UDPInit(const CSocketAddress& local, SocketRole role);
+    HRESULT UDPInit(const CSocketAddress& local, SocketRole role, bool fSetReuseFlag);
     HRESULT TCPInit(const CSocketAddress& local, SocketRole role, bool fSetReuseFlag);
 };
 

resources/stunserver.1

@@ -221,7 +221,18 @@ the same process (each in a separate thread).
 The fields of each configuration node are named identical to the
 corresponding command line parameters (with the leading dashes removed).
 An example stun.conf configuration file is shipped in the "testcode"
-folder of the source package ____
+folder of the source package
+.PP
+   *   *   *   *   *
+.PP
+\f[B]\-\-reuseaddr\f[]
+.PP
+The \-\-reuseaddr switch allows the STUN server port to be shared with
+other processes.
+This is useful for scenarios where another process needs to send from
+the STUN server port.
+.PP
+   *   *   *   *   *
 .PP
 \f[B]\-\-help\f[]
 .PP

resources/stunserver.md

@@ -198,6 +198,12 @@ configuration file is shipped in the "testcode" folder of the source package
 
 ____
 
+**--reuseaddr**
+
+The --reuseaddr switch allows the STUN server port to be shared with other processes. This is useful for scenarios where another process needs to send from the STUN server port.
+
+____
+
 **--help**
 
 Prints this help page

server/main.cpp

@@ -128,6 +128,7 @@ struct StartupArgs
     std::string strMaxConnections;
     std::string strDosProtect;
     std::string strConfigFile;
+    std::string strReuseAddr;
     
 };
 
@@ -149,6 +150,7 @@ void DumpStartupArgs(StartupArgs& args)
     PRINTARG(strVerbosity);
     PRINTARG(strMaxConnections);
     PRINTARG(strDosProtect);
+    PRINTARG(strReuseAddr);
     Logging::LogMsg(LL_DEBUG, "--------------------------\n");
 }
 
@@ -508,6 +510,9 @@ HRESULT BuildServerConfigurationFromArgs(StartupArgs& argsIn, CStunServerConfig*
     // ---- DDOS PROTECTION SWITCH -------------------------------------------
     config.fEnableDosProtection = (argsIn.strDosProtect.length() > 0);
 
+    // ---- REUSE ADDRESS SWITCH -------------------------------------------
+    config.fReuseAddr = (argsIn.strReuseAddr.length() > 0);
+
     *pConfigOut = config;
     hr = S_OK;
 
@@ -536,6 +541,7 @@ HRESULT ParseCommandLineArgs(int argc, char** argv, int startindex, StartupArgs*
     cmdline.AddOption("verbosity", required_argument, &pStartupArgs->strVerbosity);
     cmdline.AddOption("ddp", no_argument, &pStartupArgs->strDosProtect);
     cmdline.AddOption("configfile", required_argument, &pStartupArgs->strConfigFile);
+    cmdline.AddOption("reuseaddr", no_argument, &pStartupArgs->strReuseAddr);
 
     cmdline.ParseCommandLine(argc, argv, startindex, &fError);
 
@@ -591,6 +597,7 @@ HRESULT LoadConfigsFromFile(const std::string& filename, std::vector<StartupArgs
             args.strProtocol = child.get("protocol", "");
             args.strMaxConnections = child.get("maxconn", "");
             args.strDosProtect = child.get("ddp", "");
+            args.strReuseAddr = child.get("reuseaddr", "");
             
             configurations.push_back(args);
         }

server/server.cpp

@@ -32,7 +32,8 @@ fHasAA(false),
 fMultiThreadedMode(false),
 fTCP(false),
 nMaxConnections(0), // zero means default
-fEnableDosProtection(false)
+fEnableDosProtection(false),
+fReuseAddr(false)
 {
     ;
 }
@@ -50,13 +51,13 @@ CStunServer::~CStunServer()
     Shutdown();
 }
 
-HRESULT CStunServer::AddSocket(TransportAddressSet* pTSA, SocketRole role, const CSocketAddress& addrListen, const CSocketAddress& addrAdvertise)
+HRESULT CStunServer::AddSocket(TransportAddressSet* pTSA, SocketRole role, const CSocketAddress& addrListen, const CSocketAddress& addrAdvertise, bool fSetReuseFlag)
 {
     HRESULT hr = S_OK;
     
     ASSERT(IsValidSocketRole(role));
     
-    Chk(_arrSockets[role].UDPInit(addrListen, role));
+    Chk(_arrSockets[role].UDPInit(addrListen, role, fSetReuseFlag));
     ChkA(_arrSockets[role].EnablePktInfoOption(true));
 
 
@@ -110,25 +111,25 @@ HRESULT CStunServer::Initialize(const CStunServerConfig& config)
     // Create the sockets and initialize the TSA thing
     if (config.fHasPP)
     {
-        Chk(AddSocket(&tsa, RolePP, config.addrPP, config.addrPrimaryAdvertised));
+        Chk(AddSocket(&tsa, RolePP, config.addrPP, config.addrPrimaryAdvertised, config.fReuseAddr));
         socketcount++;
     }
 
     if (config.fHasPA)
     {
-        Chk(AddSocket(&tsa, RolePA, config.addrPA, config.addrPrimaryAdvertised));
+        Chk(AddSocket(&tsa, RolePA, config.addrPA, config.addrPrimaryAdvertised, config.fReuseAddr));
         socketcount++;
     }
 
     if (config.fHasAP)
     {
-        Chk(AddSocket(&tsa, RoleAP, config.addrAP, config.addrAlternateAdvertised));
+        Chk(AddSocket(&tsa, RoleAP, config.addrAP, config.addrAlternateAdvertised, config.fReuseAddr));
         socketcount++;
     }
 
     if (config.fHasAA)
     {
-        Chk(AddSocket(&tsa, RoleAA, config.addrAA, config.addrAlternateAdvertised));
+        Chk(AddSocket(&tsa, RoleAA, config.addrAA, config.addrAlternateAdvertised, config.fReuseAddr));
         socketcount++;
     }
 

server/server.h

@@ -50,6 +50,8 @@ public:
     
     bool fEnableDosProtection; // enable denial of service protection
 
+    bool fReuseAddr; // if true, the socket option SO_REUSEADDR will be set
+
     CStunServerConfig();
 };
 
@@ -71,7 +73,7 @@ private:
 
     CRefCountedPtr<IStunAuth> _spAuth;
     
-    HRESULT AddSocket(TransportAddressSet* pTSA, SocketRole role, const CSocketAddress& addrListen, const CSocketAddress& addrAdvertise);
+    HRESULT AddSocket(TransportAddressSet* pTSA, SocketRole role, const CSocketAddress& addrListen, const CSocketAddress& addrAdvertise, bool fSetReuseFlag);
     
 public:
 

testcode/testrecvfromex.cpp

@@ -70,9 +70,9 @@ HRESULT CTestRecvFromEx::DoTest(bool fIPV6)
     
     
     // create two sockets listening on INADDR_ANY.  One for sending and one for receiving
-    ChkA(socketSend.UDPInit(addrAny, RolePP));
+    ChkA(socketSend.UDPInit(addrAny, RolePP, false));
 
-    ChkA(socketRecv.UDPInit(addrAny, RolePP));
+    ChkA(socketRecv.UDPInit(addrAny, RolePP, false));
     
     socketRecv.EnablePktInfoOption(true);