WebLogic, dramatic reduction of TLS sessions creation by rejectClientInitiatedRenegotiation

why the TLS Sessions are constantly invalidated, removed from cache and recreated, discovering that it's WLS SSLConfigUtils.configureClientInitSecureRenegotiation() who initiates this:

at sun.security.ssl.SSLSessionContextImpl.remove(SSLSessionContextImpl.java:132)

at sun.security.ssl.SSLSessionImpl.invalidate(SSLSessionImpl.java:673)

at weblogic.socket.utils.SSLConfigUtils.configureClientInitSecureRenegotiation(SSLConfigUtils.java:27)

at weblogic.socket.JSSEFilterImpl.doHandshake(JSSEFilterImpl.java:135)

at weblogic.socket.JSSEFilterImpl.isMessageComplete(JSSEFilterImpl.java:354)

at weblogic.socket.SocketMuxer.readReadySocketOnce(SocketMuxer.java:976)

at weblogic.socket.SocketMuxer.readReadySocket(SocketMuxer.java:917)

at weblogic.socket.NIOSocketMuxer.process(NIOSocketMuxer.java:599)

at weblogic.socket.NIOSocketMuxer.processSockets(NIOSocketMuxer.java:563)

at weblogic.socket.SocketReaderRequest.run(SocketReaderRequest.java:30)

at weblogic.socket.SocketReaderRequest.execute(SocketReaderRequest.java:43)

at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:147)

at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:119)

the code responsible is:

public static void configureClientInitSecureRenegotiation(SSLEngine sslEngine, boolean clientInitSecureRenegotiation)

 {

   if (!IS_JDK_CLIENT_INIT_SECURE_RENEGOTIATION_PROPERTY_SET)

   {

     if ((sslEngine != null) && (!sslEngine.getUseClientMode()))

     {

       if (!clientInitSecureRenegotiation) {

         sslEngine.getSession().invalidate();

       }

       sslEngine.setEnableSessionCreation(clientInitSecureRenegotiation);

       if (isLoggable()) {

         SocketLogger.logDebug(clientInitSecureRenegotiation ? "Enabled" : "Disabled TLS client initiated secure renegotiation.");

       }

     }

   }

   else if (isLoggable()) {

     SocketLogger.logDebug("TLS client initiated secure renegotiation setting is configured with -Djdk.tls.rejectClientInitiatedRenegotiation");

   }

 }

so the invalidate() is called only if !clientInitSecureRenegotiation , but it appears that clientInitSecureRenegotiation=isClientInitSecureRenegotiationAccepted is always FALSE





in JSSESocketFactory:

  JSSEFilterImpl getJSSEFilterImpl(Socket connectedSocket, String host, int port)

    throws IOException

  {

    SSLEngine sslEngine = getSSLEngine(host, port);

    return new JSSEFilterImpl(connectedSocket, sslEngine, true);

  }

in JSSEFilterImpl:

public JSSEFilterImpl(Socket sock, SSLEngine engine, boolean clientMode)

    throws IOException

  {

    this(sock, engine, clientMode, false);  // parameter 4 is isClientInitSecureRenegotiationAccepted, THIS IS ALWAYS FALSE, and clientMode is always TRUE

  }

   

  public JSSEFilterImpl(Socket sock, SSLEngine engine, boolean clientMode, boolean isClientInitSecureRenegotiationAccepted)  // this constructor is ultimately invoked

    throws IOException

  {

so the only way to avoid session invalidation is by having IS_JDK_CLIENT_INIT_SECURE_RENEGOTIATION_PROPERTY_SET=false, that is by setting -Djdk.tls.rejectClientInitiatedRenegotiation=false (true or false doesn't seem to matter, as long as the variable is set)


Thanks to Carlo for the excellent analysis.

SSL renegotiation and resumption

"Resumption and renegotiation are rather opposites. Resumption restarts a previous TLS session in a new TCP connection, using the same TLS parameters. Renegotiation continues an existing TLS session in the same TCP connection, but changes some of the parameters.
"


in Fiddler, check for the renegotiation_info field in the CONNECT requestsmethods


https://www.ssllabs.com/ssltest/


Secure Renegotiation Supported
Secure Client-Initiated Renegotiation Yes
Insecure Client-Initiated Renegotiation No

Session resumption (caching) Yes
Session resumption (tickets) No


check DisableRenegoOnClient link


https://www.salt.ky/disabling-tlsssl-renegotiation-in-configuration-manager-2012/ and https://support.microsoft.com/en-us/help/977377/microsoft-security-advisory-vulnerability-in-tls-ssl-could-allow-spoof

"Modify the key to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\SecurityProviders\SCHANNEL\DisableRenegoOnClient | DWORD=0"



https://backstage.forgerock.com/knowledge/kb/article/a28022128 -Djdk.tls.rejectClientInitiatedRenegotiation=true


-Dsun.security.ssl.allowUnsafeRenegotiation=true ( see https://www.oracle.com/technetwork/java/javase/tlsreadme2-176330.html on why this is a bad idea)

Doc on Session Resumption https://spacehost.de/tls-session-resumption-caching-tickets/

jdk.tls.useExtendedMasterSecret=false
jdk.tls.allowLegacyResumption=true
jdk.tls.allowLegacyMasterSecret=true


Here more explanation on Resumption and Renegotiation



To understand JSSE in general read this guide https://docs.oracle.com/javase/8/docs/technotes/guides/security/jsse/JSSERefGuide.html