stun.cxx

这是国外的resip协议栈

      msg->msgHdr.id.octet[i+2]= r>>16;
      msg->msgHdr.id.octet[i+3]= r>>24;
   }
	
   if ( id != 0 )
   {
      msg->msgHdr.id.octet[0] = id; 
   }
	
   msg->hasChangeRequest = true;
   msg->changeRequest.value =(changeIp?ChangeIpFlag:0) | 
      (changePort?ChangePortFlag:0);
	
   if ( username.sizeValue > 0 )
   {
      msg->hasUsername = true;
      msg->username = username;
   }
}


static void 
stunSendTest( resip::Socket myFd, StunAddress4& dest, 
              const StunAtrString& username, const StunAtrString& password, 
              int testNum, bool verbose )
{ 
   assert( dest.addr != 0 );
   assert( dest.port != 0 );
	
   bool changePort=false;
   bool changeIP=false;
   bool discard=false;
	
   switch (testNum)
   {
      case 1:
      case 10:
      case 11:
         break;
      case 2:
         //changePort=true;
         changeIP=true;
         break;
      case 3:
         changePort=true;
         break;
      case 4:
         changeIP=true;
         break;
      case 5:
         discard=true;
         break;
      default:
         cerr << "Test " << testNum <<" is unkown\n";
         assert(0);
   }
	
   StunMessage req;
   memset(&req, 0, sizeof(StunMessage));
	
   stunBuildReqSimple( &req, username, 
                       changePort , changeIP , 
                       testNum );
	
   char buf[STUN_MAX_MESSAGE_SIZE];
   int len = STUN_MAX_MESSAGE_SIZE;
	
   len = stunEncodeMessage( req, buf, len, password,verbose );
	
   if ( verbose )
   {
      clog << "About to send msg of len " << len << " to " << dest << endl;
   }
	
   sendMessage( myFd, buf, len, dest.addr, dest.port, verbose );

}


void 
stunGetUserNameAndPassword(  const StunAddress4& dest, 
                             StunAtrString* username,
                             StunAtrString* password)
{ 
   // !cj! This is totally bogus - need to make TLS connection to dest and get a
   // username and password to use 
   stunCreateUserName(dest, username);
   stunCreatePassword(*username, password);
}


bool 
stunTest( StunAddress4& dest, int testNum, bool verbose, StunAddress4* sAddr, unsigned long timeoutMs )
{ 
   assert( dest.addr != 0 );
   assert( dest.port != 0 );
	
   int port = stunRandomPort();
   UInt32 interfaceIp=0;
   if (sAddr)
   {
      interfaceIp = sAddr->addr;
      if ( sAddr->port != 0 )
      {
        port = sAddr->port;
      }
   }
   resip::Socket myFd = openPort(port,interfaceIp,verbose);

   if (myFd == INVALID_SOCKET)
   {
	   return false;
   }

   // make socket non-blocking
   if (!makeSocketNonBlocking(myFd))
   {
      return false;
   }
	
   StunAtrString username;
   StunAtrString password;
	
   username.sizeValue = 0;
   password.sizeValue = 0;
	
#ifdef USE_TLS
   stunGetUserNameAndPassword( dest, username, password );
#endif
	
   stunSendTest( myFd, dest, username, password, testNum, verbose );
    
   char msg[STUN_MAX_MESSAGE_SIZE];
   int msgLen = STUN_MAX_MESSAGE_SIZE;
	
   // Wait to receive a packet
   resip::FdSet myFdSet;
   myFdSet.setRead(myFd);
   if (myFdSet.selectMilliSeconds(timeoutMs) < 1)
   {
      // no packet received or an error occured
      return false;
   }

   StunAddress4 from;
   if (!getMessage(myFd, msg, &msgLen, &from.addr, &from.port, verbose))
   {
	   closeSocket(myFd);
	   return false;
   }
	
   StunMessage resp;
   memset(&resp, 0, sizeof(StunMessage));
	
   if ( verbose ) clog << "Got a response" << endl;

   bool ok = stunParseMessage( msg,msgLen, resp,verbose );
	
   if ( verbose )
   {
      clog << "\t ok=" << ok << endl;
      clog << "\t id=" << resp.msgHdr.id << endl;
      clog << "\t mappedAddr=" << resp.mappedAddress.ipv4 << endl;
      clog << "\t changedAddr=" << resp.changedAddress.ipv4 << endl;
      clog << endl;
   }
	
   if (sAddr)
   {
      sAddr->port = resp.mappedAddress.ipv4.port;
      sAddr->addr = resp.mappedAddress.ipv4.addr;
   }

   closeSocket(myFd);
   return ok;
}


NatType
stunNatType( StunAddress4& dest, 
             bool verbose,
             bool* preservePort, // if set, is return for if NAT preservers ports or not
             bool* hairpin,  // if set, is the return for if NAT will hairpin packets
             int port, // port to use for the test, 0 to choose random port
             StunAddress4* sAddr // NIC to use 
   )
{ 
   assert( dest.addr != 0 );
   assert( dest.port != 0 );
	
   if ( hairpin ) 
   {
      *hairpin = false;
   }
	
   if ( port == 0 )
   {
      port = stunRandomPort();
   }
   UInt32 interfaceIp=0;
   if (sAddr)
   {
      interfaceIp = sAddr->addr;
   }
   resip::Socket myFd1 = openPort(port,interfaceIp,verbose);
   resip::Socket myFd2 = openPort(port+1,interfaceIp,verbose);

   if ( ( myFd1 == INVALID_SOCKET) || ( myFd2 == INVALID_SOCKET) )
   {
        cerr << "Some problem opening port/interface to send on" << endl;
       return StunTypeFailure; 
   }

   assert( myFd1 != INVALID_SOCKET );
   assert( myFd2 != INVALID_SOCKET );
    
   bool respTestI=false;
   bool isNat=true;
   StunAddress4 testIchangedAddr;
   StunAddress4 testImappedAddr;
   bool respTestI2=false; 
   bool mappedIpSame = true;
   StunAddress4 testI2mappedAddr;
   StunAddress4 testI2dest=dest;
   bool respTestII=false;
   bool respTestIII=false;

   bool respTestHairpin=false;
   bool respTestPreservePort=false;
	
   memset(&testImappedAddr,0,sizeof(testImappedAddr));
	
   StunAtrString username;
   StunAtrString password;
	
   username.sizeValue = 0;
   password.sizeValue = 0;
	
#ifdef USE_TLS 
   stunGetUserNameAndPassword( dest, username, password );
#endif
	
   int count=0;
   while ( count < 7 )
   {
      struct timeval tv;
      fd_set fdSet; 
#ifdef WIN32
      unsigned int fdSetSize;
#else
      int fdSetSize;
#endif
      FD_ZERO(&fdSet); fdSetSize=0;
      FD_SET(myFd1,&fdSet); fdSetSize = (myFd1+1>fdSetSize) ? myFd1+1 : fdSetSize;
      FD_SET(myFd2,&fdSet); fdSetSize = (myFd2+1>fdSetSize) ? myFd2+1 : fdSetSize;
      tv.tv_sec=0;
      tv.tv_usec=150*1000; // 150 ms 
      if ( count == 0 ) tv.tv_usec=0;
		
      int  err = select(fdSetSize, &fdSet, NULL, NULL, &tv);
      int e = getErrno();
      if ( err == SOCKET_ERROR )
      {
         // error occured
         cerr << "Error " << e << " " << strerror(e) << " in select" << endl;
        return StunTypeFailure; 
     }
      else if ( err == 0 )
      {
         // timeout occured 
         count++;
			
         if ( !respTestI ) 
         {
            stunSendTest( myFd1, dest, username, password, 1 ,verbose );
         }         
			
         if ( (!respTestI2) && respTestI ) 
         {
            // check the address to send to if valid 
            if (  ( testI2dest.addr != 0 ) &&
                  ( testI2dest.port != 0 ) )
            {
               stunSendTest( myFd1, testI2dest, username, password, 10  ,verbose);
            }
         }
			
         if ( !respTestII )
         {
            stunSendTest( myFd2, dest, username, password, 2 ,verbose );
         }
			
         if ( !respTestIII )
         {
            stunSendTest( myFd2, dest, username, password, 3 ,verbose );
         }
			
         if ( respTestI && (!respTestHairpin) )
         {
            if (  ( testImappedAddr.addr != 0 ) &&
                  ( testImappedAddr.port != 0 ) )
            {
               stunSendTest( myFd1, testImappedAddr, username, password, 11 ,verbose );
            }
         }
      }
      else
      {
         //if (verbose) clog << "-----------------------------------------" << endl;
         assert( err>0 );
         // data is avialbe on some fd 
			
         for ( int i=0; i<2; i++)
         {
            resip::Socket myFd;
            if ( i==0 ) 
            {
               myFd=myFd1;
            }
            else
            {
               myFd=myFd2;
            }
				
            if ( myFd!=INVALID_SOCKET ) 
            {					
               if ( FD_ISSET(myFd,&fdSet) )
               {
                  char msg[STUN_MAX_MESSAGE_SIZE];
                  int msgLen = sizeof(msg);
                  						
                  StunAddress4 from;
						
                  getMessage( myFd,
                              msg,
                              &msgLen,
                              &from.addr,
                              &from.port,verbose );
						
                  StunMessage resp;
                  memset(&resp, 0, sizeof(StunMessage));
						
                  stunParseMessage( msg,msgLen, resp,verbose );
						
                  if ( verbose )
                  {
                     clog << "Received message of type " << resp.msgHdr.msgType 
                          << "  id=" << (int)(resp.msgHdr.id.octet[0]) << endl;
                  }
						
                  switch( resp.msgHdr.id.octet[0] )
                  {
                     case 1:
                     {
                        if ( !respTestI )
                        {
									
                           testIchangedAddr.addr = resp.changedAddress.ipv4.addr;
                           testIchangedAddr.port = resp.changedAddress.ipv4.port;
                           testImappedAddr.addr = resp.mappedAddress.ipv4.addr;
                           testImappedAddr.port = resp.mappedAddress.ipv4.port;
			
                           respTestPreservePort = ( testImappedAddr.port == port ); 
                           if ( preservePort )
                           {
                              *preservePort = respTestPreservePort;
                           }								
									
                           testI2dest.addr = resp.changedAddress.ipv4.addr;
									
                           if (sAddr)
                           {
                              sAddr->port = testImappedAddr.port;
                              sAddr->addr = testImappedAddr.addr;
                           }
									
                           count = 0;
                        }		
                        respTestI=true;
                     }
                     break;
                     case 2:
                     {  
                        respTestII=true;
                     }
                     break;
                     case 3:
                     {
                        respTestIII=true;
                     }
                     break;
                     case 10:
                     {
                        if ( !respTestI2 )
                        {
                           testI2mappedAddr.addr = resp.mappedAddress.ipv4.addr;
                           testI2mappedAddr.port = resp.mappedAddress.ipv4.port;
								
                           mappedIpSame = false;
                           if ( (testI2mappedAddr.addr  == testImappedAddr.addr ) &&
                                (testI2mappedAddr.port == testImappedAddr.port ))
                           { 
                              mappedIpSame = true;
                           }
								
							
                        }
                        respTestI2=true;
                     }
                     break;
                     case 11:
                     {
							
                        if ( hairpin ) 
                        {
                           *hairpin = true;
                        }
                        respTestHairpin = true;
                     }
                     break;
                  }
               }
            }
         }
      }
   }

   closeSocket(myFd1);
   closeSocket(myFd2);

   // see if we can bind to this address 
   //cerr << "try binding to " << testImappedAddr << endl;
   resip::Socket s = openPort( 0/*use ephemeral*/, testImappedAddr.addr, false );
   if ( s != INVALID_SOCKET )
   {
      closeSocket(s);
      isNat = false;
      //cerr << "binding worked" << endl;
   }
   else
   {
      isNat = true;
      //cerr << "binding failed" << endl;
   }
	
   if (verbose)
   {
      clog << "test I = " << respTestI << endl;
      clog << "test II = " << respTestII << endl;
      clog << "test III = " << respTestIII << endl;
      clog << "test I(2) = " << respTestI2 << endl;
      clog << "is nat  = " << isNat <<endl;
      clog << "mapped IP same = " << mappedIpSame << endl;
      clog << "hairpin = " << respTestHairpin << endl;
      clog << "preserver port = " << respTestPreservePort << endl;
   }
	
#if 0
   // implement logic flow chart from draft RFC
   if ( respTestI )
   {
      if ( isNat )
      {
         if (respTestII)
         {
            return StunTypeConeNat;
         }
         else
         {
            if ( mappedIpSame )
            {
               if ( respTestIII )
               {
                  return StunTypeRestrictedNat;
               }
               else
               {
                  return StunTypePortRestrict