natplugins/natptraversalcontroller/src/cnattraversalsession.cpp
changeset 0 1bce908db942
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     1 /*
       
     2 * Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies).
       
     3 * All rights reserved.
       
     4 * This component and the accompanying materials are made available
       
     5 * under the terms of "Eclipse Public License v1.0"
       
     6 * which accompanies this distribution, and is available
       
     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".
       
     8 *
       
     9 * Initial Contributors:
       
    10 * Nokia Corporation - initial contribution.
       
    11 *
       
    12 * Contributors:
       
    13 *
       
    14 * Description: 
       
    15 *
       
    16 */
       
    17 
       
    18 
       
    19 #include "cnattraversalsession.h"
       
    20 #include "cnattraversalconfig.h"
       
    21 #include "cnatbinding.h"
       
    22 #include "cnatbindingstunrefresher.h"
       
    23 #include "cnatbindingcrlfrefresher.h"
       
    24 #include "cnatbindingstunandcrlfrefresher.h"
       
    25 #include "cudpcrlfsender.h"
       
    26 #include "ctcpcrlfsender.h"
       
    27 #include "ctlscrlfsender.h"
       
    28 #include "sipnatbindingobserver.h"
       
    29 #include "nattraversallog.h"
       
    30 
       
    31 _LIT8(KZeroIPAddress, "0.0.0.0");
       
    32 
       
    33 // The following addresses are private (RFC 1918):
       
    34 // 10.0.0.0 - 10.255.255.255
       
    35 const TUint32 KPrivateRange1Low  = INET_ADDR(10,0,0,0);
       
    36 const TUint32 KPrivateRange1High = INET_ADDR(10,255,255,255);
       
    37 
       
    38 // 172.16.0.0 - 172.31.255.255
       
    39 const TUint32 KPrivateRange2Low  = INET_ADDR(172,16,0,0);
       
    40 const TUint32 KPrivateRange2High = INET_ADDR(172,31,255,255);
       
    41 
       
    42 // 192.168.0.0 - 192.168.255.255
       
    43 const TUint32 KPrivateRange3Low  = INET_ADDR(192,168,0,0);
       
    44 const TUint32 KPrivateRange3High = INET_ADDR(192,168,255,255);
       
    45 
       
    46 
       
    47 // -----------------------------------------------------------------------------
       
    48 // CNATTraversalSession::NewL
       
    49 // -----------------------------------------------------------------------------
       
    50 //
       
    51 CNATTraversalSession* CNATTraversalSession::NewL(
       
    52     CDeltaTimer& aDeltaTimer,
       
    53     RSocketServ& aSocketServ,
       
    54     RConnection& aConnection,
       
    55     const TInetAddr& aLocalAddr,
       
    56     const TInetAddr& aNextHopAddr,
       
    57     CNATTraversalConfig* aConfig,
       
    58     MSTUNClientObserver& aObserver,
       
    59     MNATTraversalSocketManager& aSocketManager)
       
    60     {
       
    61     CNATTraversalSession* self =
       
    62         CNATTraversalSession::NewLC(aDeltaTimer,aSocketServ,aConnection,
       
    63                                     aLocalAddr,aNextHopAddr,aConfig,
       
    64                                     aObserver,aSocketManager);
       
    65     CleanupStack::Pop(self);
       
    66     return self;
       
    67     }
       
    68 
       
    69 // -----------------------------------------------------------------------------
       
    70 // CNATTraversalSession::NewL
       
    71 // -----------------------------------------------------------------------------
       
    72 //
       
    73 CNATTraversalSession* CNATTraversalSession::NewLC(
       
    74     CDeltaTimer& aDeltaTimer,
       
    75     RSocketServ& aSocketServ,
       
    76     RConnection& aConnection,
       
    77     const TInetAddr& aLocalAddr,
       
    78     const TInetAddr& aNextHopAddr,
       
    79     CNATTraversalConfig* aConfig,
       
    80     MSTUNClientObserver& aObserver,
       
    81     MNATTraversalSocketManager& aSocketManager)
       
    82     {
       
    83     CNATTraversalSession* self =
       
    84         new(ELeave)CNATTraversalSession(
       
    85             aLocalAddr,aNextHopAddr,aDeltaTimer,aSocketManager);
       
    86     CleanupStack::PushL(self);
       
    87     self->ConstructL(aSocketServ,aConnection,aConfig,aObserver);
       
    88     return self;
       
    89     }
       
    90 
       
    91 // -----------------------------------------------------------------------------
       
    92 // CNATTraversalSession::CNATTraversalSession
       
    93 // -----------------------------------------------------------------------------
       
    94 //
       
    95 CNATTraversalSession::CNATTraversalSession(
       
    96     const TInetAddr& aLocalAddr,
       
    97     const TInetAddr& aNextHopAddr,
       
    98     CDeltaTimer& aDeltaTimer,
       
    99     MNATTraversalSocketManager& aSocketManager)
       
   100     : iLocalAddr(aLocalAddr),
       
   101       iNextHopAddr(aNextHopAddr),
       
   102       iDeltaTimer(aDeltaTimer),
       
   103       iSocketManager(aSocketManager)
       
   104     {
       
   105     }
       
   106 
       
   107 // -----------------------------------------------------------------------------
       
   108 // CNATTraversalSession::ConstructL
       
   109 // -----------------------------------------------------------------------------
       
   110 //
       
   111 void CNATTraversalSession::ConstructL(
       
   112     RSocketServ& aSocketServ,
       
   113     RConnection& aConnection,
       
   114     CNATTraversalConfig* aConfig,
       
   115     MSTUNClientObserver& aObserver)
       
   116     {
       
   117     __ASSERT_ALWAYS(aConfig, User::Leave(KErrArgument));
       
   118 
       
   119     if (aConfig->STUNServer().Compare(KZeroIPAddress) == 0)
       
   120         {
       
   121         // With 0.0.0.0 STUN server address, STUN is not used.
       
   122         // With this configuration CRLF bursts are sent
       
   123         // to keep the possible firewall hole open.
       
   124 		__ASSERT_ALWAYS(aConfig->CRLFRefreshEnabledToProxyValue() ==
       
   125         				CNATTraversalConfig::EEnabled,
       
   126                         User::Leave(KErrArgument));
       
   127         }
       
   128     else
       
   129         {
       
   130         TBool stunServerConfigured = ETrue;
       
   131         TPtrC8 stunServerPtr(aConfig->STUNServer());
       
   132         if (stunServerPtr.Length() == 0)
       
   133             {
       
   134             stunServerPtr.Set(aConfig->Domain());
       
   135             stunServerConfigured = EFalse;
       
   136             }
       
   137 
       
   138         iSTUNClient = CSTUNClient::NewL(aConfig->STUNRetransmitTimer(),
       
   139                                         stunServerPtr,
       
   140                                         aConfig->STUNServerPort(),
       
   141                                         KStun,
       
   142                                         aSocketServ,
       
   143                                         aConnection,
       
   144                                         iDeltaTimer,
       
   145                                         aObserver,
       
   146                                         ETrue,
       
   147                                         !stunServerConfigured);
       
   148 
       
   149         if (aConfig->Username().Length() && aConfig->Password().Length())
       
   150             {
       
   151             iSTUNClient->SetCredentialsL(aConfig->Username(),
       
   152                                          aConfig->Password());
       
   153             }
       
   154         }
       
   155 
       
   156     // transfer the ownership only after calling all the leaving functions
       
   157     iConfig = aConfig;
       
   158     }
       
   159 
       
   160 // -----------------------------------------------------------------------------
       
   161 // CNATTraversalSession::~CNATTraversalSession
       
   162 // -----------------------------------------------------------------------------
       
   163 //
       
   164 CNATTraversalSession::~CNATTraversalSession()
       
   165     {
       
   166     delete iSTUNClient;
       
   167     delete iConfig;
       
   168     iBindings.ResetAndDestroy();
       
   169     }
       
   170 
       
   171 // -----------------------------------------------------------------------------
       
   172 // CNATTraversalSession::HasSTUNClient
       
   173 // -----------------------------------------------------------------------------
       
   174 //
       
   175 TBool CNATTraversalSession::HasSTUNClient(const CSTUNClient& aClient) const
       
   176     {
       
   177     return (iSTUNClient == &aClient);
       
   178     }
       
   179 
       
   180 // -----------------------------------------------------------------------------
       
   181 // CNATTraversalSession::Domain
       
   182 // -----------------------------------------------------------------------------
       
   183 //
       
   184 const TDesC8& CNATTraversalSession::Domain() const
       
   185     {
       
   186     return iConfig->Domain();
       
   187     }
       
   188 
       
   189 // -----------------------------------------------------------------------------
       
   190 // CNATTraversalSession::IapId
       
   191 // -----------------------------------------------------------------------------
       
   192 //
       
   193 TUint32 CNATTraversalSession::IapId() const
       
   194     {
       
   195     return iConfig->IapId();
       
   196     }
       
   197 
       
   198 // -----------------------------------------------------------------------------
       
   199 // CNATTraversalSession::UpdateNextHop
       
   200 // -----------------------------------------------------------------------------
       
   201 //
       
   202 void CNATTraversalSession::UpdateNextHop(const TInetAddr& aNextHopAddr)
       
   203     {
       
   204     iNextHopAddr = aNextHopAddr;
       
   205     }
       
   206 
       
   207 // -----------------------------------------------------------------------------
       
   208 // CNATTraversalSession::HasBindings
       
   209 // -----------------------------------------------------------------------------
       
   210 //
       
   211 TBool CNATTraversalSession::HasBindings() const
       
   212     {
       
   213     return (iBindings.Count() > 0);
       
   214     }
       
   215 
       
   216 // -----------------------------------------------------------------------------
       
   217 // CNATTraversalSession::HasBinding
       
   218 // -----------------------------------------------------------------------------
       
   219 //
       
   220 TBool CNATTraversalSession::HasBinding(
       
   221     const MSIPNATBindingObserver* aObserver) const
       
   222     {
       
   223     return (FindBindingIndex(aObserver) >= 0);
       
   224     }
       
   225 
       
   226 // -----------------------------------------------------------------------------
       
   227 // CNATTraversalSession::InitCompletedL
       
   228 // -----------------------------------------------------------------------------
       
   229 //
       
   230 void CNATTraversalSession::InitCompletedL()
       
   231     {
       
   232     NATTRAVERSAL_LOG("CNATTraversalSession::InitCompletedL")
       
   233     __ASSERT_ALWAYS(iSTUNClient, User::Leave(KErrCorrupt));
       
   234     iConfig->SetSharedSecretNotSupportedL(!iSTUNClient->SharedSecretObtained());
       
   235     for (TInt i=0; i<iBindings.Count(); i++)
       
   236         {
       
   237         CNATBinding* bindingHolder = iBindings[i];
       
   238         CSTUNBinding* stunBinding =
       
   239             CSTUNBinding::NewL(*iSTUNClient,bindingHolder->STUNSocket());
       
   240         bindingHolder->SetBinding(stunBinding);
       
   241         bindingHolder->SendSTUNRequestL();
       
   242         }
       
   243     }
       
   244 
       
   245 // -----------------------------------------------------------------------------
       
   246 // CNATTraversalSession::InitFailed
       
   247 // -----------------------------------------------------------------------------
       
   248 //
       
   249 void CNATTraversalSession::InitFailed(TInt aError)
       
   250     {
       
   251     NATTRAVERSAL_LOG("CNATTraversalSession::InitFailedL")
       
   252     TRAP_IGNORE(iConfig->SetBindingRequestFailedL(ETrue))
       
   253     for (TInt i=iBindings.Count()-1; i>=0; i--)
       
   254         {
       
   255         iBindings[i]->SetBindingFailed(aError);
       
   256         }
       
   257     }
       
   258 
       
   259 // -----------------------------------------------------------------------------
       
   260 // CNATTraversalSession::AddressResolvedL
       
   261 // -----------------------------------------------------------------------------
       
   262 //
       
   263 TBool CNATTraversalSession::AddressResolvedL(const CBinding& aBinding)
       
   264     {
       
   265     NATTRAVERSAL_ADDRLOG("CNATTraversalSession::AddressResolvedL",
       
   266         aBinding.PublicAddr())
       
   267     TBool found = EFalse;
       
   268     for (TInt i=iBindings.Count()-1; i>=0 && !found; i--)
       
   269         {
       
   270         CNATBinding* bindingHolder = iBindings[i];
       
   271         if (bindingHolder->Binding() == &aBinding)
       
   272             {
       
   273             found = ETrue;
       
   274             TBool publicAddrChanged =
       
   275                 bindingHolder->SetPublicAddr(aBinding.PublicAddr());
       
   276             if (publicAddrChanged)
       
   277                 {
       
   278                 // Existing public address has changed -> flow failure
       
   279                 iBindings.Remove(i);
       
   280                 bindingHolder->NATBindingObserver().FlowFailure(KErrGeneral);
       
   281                 delete bindingHolder;
       
   282                 }
       
   283             else
       
   284                 {
       
   285                 bindingHolder->ContinueRefreshing();
       
   286                 }
       
   287             }
       
   288         }
       
   289     return found;
       
   290     }
       
   291 
       
   292 // -----------------------------------------------------------------------------
       
   293 // CNATTraversalSession::BindingFailed
       
   294 // -----------------------------------------------------------------------------
       
   295 //
       
   296 TBool CNATTraversalSession::BindingFailed(
       
   297     const CBinding& aBinding,
       
   298     TInt aError)
       
   299     {
       
   300     TBool found = EFalse;
       
   301     for (TInt i=iBindings.Count()-1; i>=0 && !found; i--)
       
   302         {
       
   303         CNATBinding* bindingHolder = iBindings[i];
       
   304         if (bindingHolder->Binding() == &aBinding)
       
   305             {
       
   306             found = ETrue;
       
   307             TRAP_IGNORE(iConfig->SetBindingRequestFailedL(ETrue))
       
   308             bindingHolder->SetBindingFailed(aError);
       
   309             }
       
   310         }
       
   311     return found;
       
   312     }
       
   313 
       
   314 // -----------------------------------------------------------------------------
       
   315 // CNATTraversalSession::CreateNATBindingL
       
   316 // -----------------------------------------------------------------------------
       
   317 //
       
   318 CNATBinding& CNATTraversalSession::CreateNATBindingL(
       
   319     TUint32 aRequestId,
       
   320     RSocket& aSocket,
       
   321     MSIPNATBindingObserver& aBindingObserver,
       
   322     MSIPNATTraversalRequestObserver& aRequestObserver,
       
   323     TBool& aAsyncCallInitiated)
       
   324     {
       
   325     aAsyncCallInitiated = EFalse;
       
   326     // Initialize binding's public address with the local address
       
   327     CNATBinding* bindingHolder =
       
   328         CNATBinding::NewLC(aRequestId,aSocket,iLocalAddr,
       
   329                            aRequestObserver,aBindingObserver,
       
   330                            iSocketManager);
       
   331 
       
   332     if (iSTUNClient)
       
   333         {
       
   334         // STUN used, not only CRLF-refreshes.
       
   335         if (iSTUNClient->IsInitialized())
       
   336             {
       
   337             if (!iConfig->BindingRequestFailed())
       
   338                 {
       
   339                 CSTUNBinding* stunBinding =
       
   340                     CSTUNBinding::NewL(
       
   341                         *iSTUNClient,bindingHolder->STUNSocket());
       
   342                 bindingHolder->SetBinding(stunBinding);
       
   343                 bindingHolder->SendSTUNRequestL();
       
   344                 aAsyncCallInitiated = ETrue;
       
   345                 }
       
   346             }
       
   347         else
       
   348             {
       
   349             // STUN Client is not initialized.
       
   350             aAsyncCallInitiated = (!iConfig->BindingRequestFailed());
       
   351             }
       
   352         }
       
   353 
       
   354     iBindings.AppendL(bindingHolder);
       
   355     CleanupStack::Pop(bindingHolder);
       
   356     return *bindingHolder;
       
   357     }
       
   358 
       
   359 // -----------------------------------------------------------------------------
       
   360 // CNATTraversalSession::RefreshNATBindingL
       
   361 // -----------------------------------------------------------------------------
       
   362 //
       
   363 void CNATTraversalSession::RefreshNATBindingL(
       
   364     RSocket& aSocket,
       
   365     const MSIPNATBindingObserver* aBindingObserver,
       
   366     TBool& aMaintainPersistentConnection,
       
   367     TBool& aHandled)
       
   368     {
       
   369     aMaintainPersistentConnection = EFalse;
       
   370     aHandled = EFalse;
       
   371     TInt index = FindBindingIndex(aBindingObserver);
       
   372     if (index >= 0)
       
   373         {
       
   374         CNATBinding* binding = iBindings[index];
       
   375         if (!binding->Refresher() &&
       
   376             (IsBehindNAT(*binding) ||
       
   377              iConfig->CRLFRefreshEnabledToProxy(Protocol(aSocket))))
       
   378             {
       
   379             CreateRefresherL(*binding,aSocket,aMaintainPersistentConnection);
       
   380             }
       
   381         aMaintainPersistentConnection = binding->PersistentConnectionRequired();
       
   382         aHandled = ETrue;
       
   383         }
       
   384     }
       
   385 
       
   386 // -----------------------------------------------------------------------------
       
   387 // CNATTraversalSession::RefreshNATBindingL
       
   388 // -----------------------------------------------------------------------------
       
   389 //
       
   390 void CNATTraversalSession::RefreshNATBindingL(
       
   391     CSecureSocket& aSecureSocket,
       
   392     const MSIPNATBindingObserver* aBindingObserver,
       
   393     TBool& aMaintainPersistentConnection,
       
   394     TBool& aHandled)
       
   395     {
       
   396     aMaintainPersistentConnection = EFalse;
       
   397     aHandled = EFalse;
       
   398     TInt index = FindBindingIndex(aBindingObserver);
       
   399     if (index >= 0)
       
   400         {
       
   401         CNATBinding* binding = iBindings[index];
       
   402         if (!binding->Refresher() &&
       
   403 			(IsBehindNAT(*binding) ||
       
   404 			 iConfig->CRLFRefreshEnabledToProxy(KProtocolInetTcp)))
       
   405             {
       
   406             CTlsCRLFSender* sender =
       
   407                 new(ELeave)CTlsCRLFSender(aSecureSocket,*binding);
       
   408             CleanupStack::PushL(sender);
       
   409             CNATBindingRefresher* refresher =
       
   410                 new(ELeave)CNATBindingCRLFRefresher(
       
   411                     iDeltaTimer,
       
   412                     iConfig->TCPRefreshInterval(),
       
   413                     *binding,
       
   414                     sender);
       
   415             CleanupStack::Pop(sender);
       
   416             binding->SetRefresher(refresher);
       
   417             }
       
   418         aMaintainPersistentConnection = binding->PersistentConnectionRequired();
       
   419         aHandled = ETrue;
       
   420         }
       
   421     }
       
   422 
       
   423 // -----------------------------------------------------------------------------
       
   424 // CNATTraversalSession::SocketIdle
       
   425 // -----------------------------------------------------------------------------
       
   426 //
       
   427 void CNATTraversalSession::SocketIdle(
       
   428     TBool aIdle,
       
   429     RSocket& aSocket)
       
   430     {
       
   431     SocketIdleImpl(aIdle,aSocket);
       
   432     }
       
   433 
       
   434 // -----------------------------------------------------------------------------
       
   435 // CNATTraversalSession::SocketIdle
       
   436 // -----------------------------------------------------------------------------
       
   437 //
       
   438 void CNATTraversalSession::SocketIdle(
       
   439     TBool aIdle,
       
   440     CSecureSocket& aSocket)
       
   441     {
       
   442     SocketIdleImpl(aIdle,aSocket);
       
   443     }
       
   444 
       
   445 // -----------------------------------------------------------------------------
       
   446 // CNATTraversalSession::DataReceivedL
       
   447 // -----------------------------------------------------------------------------
       
   448 //
       
   449 void CNATTraversalSession::DataReceivedL(
       
   450     const TDesC8& aData,
       
   451     const RSocket& aSocket,
       
   452     TBool& aHandled)
       
   453     {
       
   454     for (TInt i=0; i<iBindings.Count() && !aHandled; i++)
       
   455         {
       
   456         iBindings[i]->HandleDataL(aData,aSocket,aHandled);
       
   457         }
       
   458     }
       
   459 
       
   460 // -----------------------------------------------------------------------------
       
   461 // CNATTraversalSession::RemoveBinding
       
   462 // -----------------------------------------------------------------------------
       
   463 //
       
   464 TBool CNATTraversalSession::RemoveBinding(TUint32 aRequestId)
       
   465     {
       
   466     TBool found = EFalse;
       
   467     for (TInt i=0; i<iBindings.Count() && !found; i++)
       
   468         {
       
   469         CNATBinding* binding = iBindings[i];
       
   470         if (binding->InitialRequestId() == aRequestId)
       
   471             {
       
   472             iBindings.Remove(i);
       
   473             delete binding;
       
   474             found = ETrue;
       
   475             }
       
   476         }
       
   477     return found;
       
   478     }
       
   479 
       
   480 // -----------------------------------------------------------------------------
       
   481 // CNATTraversalSession::RemoveBinding
       
   482 // -----------------------------------------------------------------------------
       
   483 //
       
   484 TBool CNATTraversalSession::RemoveBinding(
       
   485     const MSIPNATBindingObserver& aObserver)
       
   486     {
       
   487     TBool found = EFalse;
       
   488     TInt index = FindBindingIndex(&aObserver);
       
   489     if (index >= 0)
       
   490         {
       
   491         CNATBinding* binding = iBindings[index];
       
   492         iBindings.Remove(index);
       
   493         delete binding;
       
   494         found = ETrue;
       
   495         }
       
   496     return found;
       
   497     }
       
   498 
       
   499 // -----------------------------------------------------------------------------
       
   500 // CNATTraversalSession::DetachConfig
       
   501 // -----------------------------------------------------------------------------
       
   502 //
       
   503 void CNATTraversalSession::DetachConfig()
       
   504     {
       
   505     iConfig = NULL;
       
   506     }
       
   507 
       
   508 // -----------------------------------------------------------------------------
       
   509 // CNATTraversalSession::Protocol
       
   510 // -----------------------------------------------------------------------------
       
   511 //
       
   512 TUint CNATTraversalSession::Protocol(RSocket& aSocket) const
       
   513     {
       
   514     TProtocolDesc proto;
       
   515     aSocket.Info(proto);
       
   516     return proto.iProtocol;
       
   517     }
       
   518 
       
   519 // -----------------------------------------------------------------------------
       
   520 // CNATTraversalSession::RefreshInterval
       
   521 // -----------------------------------------------------------------------------
       
   522 //
       
   523 TInt CNATTraversalSession::RefreshInterval(TUint aProtocol) const
       
   524     {
       
   525     TInt interval = 0;
       
   526     if (aProtocol == KProtocolInetTcp)
       
   527         {
       
   528         interval = iConfig->TCPRefreshInterval();
       
   529         }
       
   530     if (aProtocol == KProtocolInetUdp)
       
   531         {
       
   532         interval = iConfig->UDPRefreshInterval();
       
   533         }
       
   534     return interval;
       
   535     }
       
   536 
       
   537 // -----------------------------------------------------------------------------
       
   538 // CNATTraversalSession::FindBindingIndex
       
   539 // -----------------------------------------------------------------------------
       
   540 //
       
   541 TInt CNATTraversalSession::FindBindingIndex(
       
   542     const MSIPNATBindingObserver* aBindingObserver) const
       
   543     {
       
   544     TInt index = KErrNotFound;
       
   545     for (TInt i=0; i < iBindings.Count() && index == KErrNotFound; i++)
       
   546         {
       
   547         CNATBinding* binding = iBindings[i];
       
   548         if (&(binding->NATBindingObserver()) == aBindingObserver)
       
   549             {
       
   550             index = i;
       
   551             }
       
   552         }
       
   553     return index;
       
   554     }
       
   555 
       
   556 // -----------------------------------------------------------------------------
       
   557 // CNATTraversalSession::CreateRefresherL
       
   558 // -----------------------------------------------------------------------------
       
   559 //
       
   560 void CNATTraversalSession::CreateRefresherL(
       
   561     CNATBinding& aBinding,
       
   562     RSocket& aSocket,
       
   563     TBool& aMaintainPersistentConnection)
       
   564     {
       
   565     aMaintainPersistentConnection = EFalse;
       
   566     CNATBindingRefresher* refresher = NULL;
       
   567     TUint protocol = Protocol(aSocket);
       
   568     TInt refreshInterval = RefreshInterval(protocol);
       
   569     if (protocol == KProtocolInetTcp)
       
   570         {
       
   571         CTcpCRLFSender* sender =
       
   572             new(ELeave)CTcpCRLFSender(aSocket,aBinding);
       
   573         CleanupStack::PushL(sender);
       
   574         refresher = new(ELeave)CNATBindingCRLFRefresher(iDeltaTimer,
       
   575                                                         refreshInterval,
       
   576                                                         aBinding,
       
   577                                                         sender);
       
   578         CleanupStack::Pop(sender);
       
   579         aMaintainPersistentConnection = ETrue;
       
   580         }
       
   581     else if (protocol == KProtocolInetUdp)
       
   582         {
       
   583         if (IsBehindNAT(aBinding) && aBinding.AddressResolved())
       
   584             {
       
   585             // STUN has been succesfully used to detect a NAT
       
   586             if (iSTUNClient &&
       
   587                 iNextHopAddr.Match(iSTUNClient->STUNServerAddrL()))
       
   588                 {
       
   589                 // Next hop has a STUN server -> refresh using STUN
       
   590                 refresher =
       
   591                     new(ELeave)CNATBindingSTUNRefresher(iDeltaTimer,
       
   592                                                         refreshInterval,
       
   593                                                         aBinding,
       
   594                                                         aBinding);
       
   595                 }
       
   596             else
       
   597                 {
       
   598                 // Refresh using STUN towards STUN server and
       
   599                 // using CRLF towards the SIP proxy
       
   600                 refresher = CNATBindingSTUNAndCRLFRefresher::NewL(
       
   601                     iDeltaTimer,refreshInterval,aBinding,
       
   602                     aBinding,aSocket,iNextHopAddr,iSocketManager);
       
   603                 }
       
   604             }
       
   605         else
       
   606             {
       
   607             if (iConfig->CRLFRefreshEnabledToProxy(protocol))
       
   608                 {
       
   609                 CUdpCRLFSender* sender =
       
   610                     new(ELeave)CUdpCRLFSender(
       
   611                         aSocket,iNextHopAddr,aBinding,iSocketManager);
       
   612                 CleanupStack::PushL(sender);
       
   613                 refresher =
       
   614                     new(ELeave)CNATBindingCRLFRefresher(
       
   615                         iDeltaTimer,refreshInterval,aBinding,sender);
       
   616                 CleanupStack::Pop(sender);
       
   617                 }
       
   618             }
       
   619         }
       
   620     else
       
   621         {
       
   622         User::Leave(KErrNotSupported);
       
   623         }
       
   624     aBinding.SetRefresher(refresher);
       
   625     }
       
   626 
       
   627 // -----------------------------------------------------------------------------
       
   628 // CNATTraversalSession::SocketIdleImpl
       
   629 // -----------------------------------------------------------------------------
       
   630 //
       
   631 template<class T> void CNATTraversalSession::SocketIdleImpl(
       
   632     TBool aIdle,
       
   633     T& aSocket)
       
   634     {
       
   635     for (TInt i=0; i<iBindings.Count(); i++)
       
   636         {
       
   637         CNATBindingRefresher* bindingRefresher = iBindings[i]->Refresher();
       
   638         if (bindingRefresher && bindingRefresher->HasSocket(aSocket))
       
   639             {
       
   640             bindingRefresher->SetRefresh(aIdle);
       
   641             }
       
   642         }
       
   643     }
       
   644 
       
   645 // -----------------------------------------------------------------------------
       
   646 // CNATTraversalSession::IsBehindNAT
       
   647 // -----------------------------------------------------------------------------
       
   648 //
       
   649 TBool CNATTraversalSession::IsBehindNAT(const CNATBinding& aBinding) const
       
   650     {
       
   651     TBool natDetected = EFalse;
       
   652     if (aBinding.AddressResolved())
       
   653         {
       
   654         if (!aBinding.PublicAddr().Match(iLocalAddr))
       
   655             {
       
   656             natDetected = ETrue;
       
   657             }
       
   658         }
       
   659     else
       
   660         {
       
   661         if (IsPrivateAddress(iLocalAddr))
       
   662             {
       
   663             natDetected = ETrue;
       
   664             }
       
   665         }
       
   666     return natDetected;
       
   667     }
       
   668 
       
   669 // -----------------------------------------------------------------------------
       
   670 // CNATTraversalSession::IsPrivateAddress
       
   671 // -----------------------------------------------------------------------------
       
   672 //
       
   673 TBool CNATTraversalSession::IsPrivateAddress(const TInetAddr& aAddr) const
       
   674     {
       
   675     TBool isPrivate = EFalse;
       
   676     if (aAddr.Family() == KAfInet)
       
   677         {
       
   678         // aAddr is IPv4 address, IPv6 addresses are always public
       
   679         TUint32 addr = aAddr.Address();
       
   680         if ((addr >= KPrivateRange1Low && addr <= KPrivateRange1High) ||
       
   681             (addr >= KPrivateRange2Low && addr <= KPrivateRange2High) ||
       
   682             (addr >= KPrivateRange3Low && addr <= KPrivateRange3High))
       
   683                 {
       
   684                 isPrivate = ETrue;
       
   685                 }
       
   686         }
       
   687     return isPrivate;
       
   688     }
       
   689