org.apache.mina.filter
Class SSLFilter

java.lang.Object
  extended by org.apache.mina.common.IoFilterAdapter
      extended by org.apache.mina.filter.SSLFilter
All Implemented Interfaces:
org.apache.mina.common.IoFilter

public class SSLFilter
extends org.apache.mina.common.IoFilterAdapter

An SSL filter that encrypts and decrypts the data exchanged in the session. Adding this filter triggers SSL handshake procedure immediately by sending a SSL 'hello' message, so you don't need to call startSSL(IoSession) manually unless you are implementing StartTLS (see below).

This filter uses an SSLEngine which was introduced in Java 5, so Java version 5 or above is mandatory to use this filter. And please note that this filter only works for TCP/IP connections.

This filter logs debug information using SessionLog.

Implementing StartTLS

You can use DISABLE_ENCRYPTION_ONCE attribute to implement StartTLS:

 public void messageReceived(IoSession session, Object message) {
    if (message instanceof MyStartTLSRequest) {
        // Insert SSLFilter to get ready for handshaking
        session.getFilterChain().addFirst(sslFilter);

        // Disable encryption temporarilly.
        // This attribute will be removed by SSLFilter
        // inside the Session.write() call below.
        session.setAttribute(SSLFilter.DISABLE_ENCRYPTION_ONCE, Boolean.TRUE);

        // Write StartTLSResponse which won't be encrypted.
        session.write(new MyStartTLSResponse(OK));
        
        // Now DISABLE_ENCRYPTION_ONCE attribute is cleared.
        assert session.getAttribute(SSLFilter.DISABLE_ENCRYPTION_ONCE) == null;
    }
 }
 


Nested Class Summary
static class SSLFilter.SSLFilterMessage
          A message that is sent from SSLFilter when the connection became secure or is not secure anymore.
 
Nested classes/interfaces inherited from interface org.apache.mina.common.IoFilter
org.apache.mina.common.IoFilter.NextFilter, org.apache.mina.common.IoFilter.WriteRequest
 
Field Summary
static java.lang.String DISABLE_ENCRYPTION_ONCE
          A session attribute key that makes next one write request bypass this filter (not encrypting the data).
static SSLFilter.SSLFilterMessage SESSION_SECURED
          A special message object which is emitted with a IoHandler.messageReceived(IoSession, Object) event when the session is secured and its USE_NOTIFICATION attribute is set.
static SSLFilter.SSLFilterMessage SESSION_UNSECURED
          A special message object which is emitted with a IoHandler.messageReceived(IoSession, Object) event when the session is not secure anymore and its USE_NOTIFICATION attribute is set.
static java.lang.String SSL_SESSION
          A session attribute key that stores underlying SSLSession for each session.
static java.lang.String USE_NOTIFICATION
          A session attribute key that makes this filter to emit a IoHandler.messageReceived(IoSession, Object) event with a special message (SESSION_SECURED or SESSION_UNSECURED).
 
Constructor Summary
SSLFilter(javax.net.ssl.SSLContext sslContext)
          Creates a new SSL filter using the specified SSLContext.
 
Method Summary
 void filterClose(org.apache.mina.common.IoFilter.NextFilter nextFilter, org.apache.mina.common.IoSession session)
           
 void filterWrite(org.apache.mina.common.IoFilter.NextFilter nextFilter, org.apache.mina.common.IoSession session, org.apache.mina.common.IoFilter.WriteRequest writeRequest)
           
 java.lang.String[] getEnabledCipherSuites()
          Returns the list of cipher suites to be enabled when SSLEngine is initialized.
 java.lang.String[] getEnabledProtocols()
          Returns the list of protocols to be enabled when SSLEngine is initialized.
 javax.net.ssl.SSLSession getSSLSession(org.apache.mina.common.IoSession session)
          Returns the underlying SSLSession for the specified session.
 boolean isNeedClientAuth()
          Returns true if the engine will require client authentication.
 boolean isSSLStarted(org.apache.mina.common.IoSession session)
          Returns true if and only if the specified session is encrypted/decrypted over SSL/TLS currently.
 boolean isUseClientMode()
          Returns true if the engine is set to use client mode when handshaking.
 boolean isWantClientAuth()
          Returns true if the engine will request client authentication.
 void messageReceived(org.apache.mina.common.IoFilter.NextFilter nextFilter, org.apache.mina.common.IoSession session, java.lang.Object message)
           
 void messageSent(org.apache.mina.common.IoFilter.NextFilter nextFilter, org.apache.mina.common.IoSession session, java.lang.Object message)
           
 void onPostAdd(org.apache.mina.common.IoFilterChain parent, java.lang.String name, org.apache.mina.common.IoFilter.NextFilter nextFilter)
           
 void onPreAdd(org.apache.mina.common.IoFilterChain parent, java.lang.String name, org.apache.mina.common.IoFilter.NextFilter nextFilter)
           
 void onPreRemove(org.apache.mina.common.IoFilterChain parent, java.lang.String name, org.apache.mina.common.IoFilter.NextFilter nextFilter)
           
 void sessionClosed(org.apache.mina.common.IoFilter.NextFilter nextFilter, org.apache.mina.common.IoSession session)
           
 void setEnabledCipherSuites(java.lang.String[] cipherSuites)
          Sets the list of cipher suites to be enabled when SSLEngine is initialized.
 void setEnabledProtocols(java.lang.String[] protocols)
          Sets the list of protocols to be enabled when SSLEngine is initialized.
 void setNeedClientAuth(boolean needClientAuth)
          Configures the engine to require client authentication.
 void setUseClientMode(boolean clientMode)
          Configures the engine to use client (or server) mode when handshaking.
 void setWantClientAuth(boolean wantClientAuth)
          Configures the engine to request client authentication.
 boolean startSSL(org.apache.mina.common.IoSession session)
          (Re)starts SSL session for the specified session if not started yet.
 org.apache.mina.common.WriteFuture stopSSL(org.apache.mina.common.IoSession session)
          Stops the SSL session by sending TLS close_notify message to initiate TLS closure.
 
Methods inherited from class org.apache.mina.common.IoFilterAdapter
destroy, exceptionCaught, init, onPostRemove, sessionCreated, sessionIdle, sessionOpened
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

SSL_SESSION

public static final java.lang.String SSL_SESSION
A session attribute key that stores underlying SSLSession for each session.


DISABLE_ENCRYPTION_ONCE

public static final java.lang.String DISABLE_ENCRYPTION_ONCE
A session attribute key that makes next one write request bypass this filter (not encrypting the data). This is a marker attribute, which means that you can put whatever as its value. (Boolean.TRUE is preferred.) The attribute is automatically removed from the session attribute map as soon as IoSession.write(Object) is invoked, and therefore should be put again if you want to make more messages bypass this filter. This is especially useful when you implement StartTLS.


USE_NOTIFICATION

public static final java.lang.String USE_NOTIFICATION
A session attribute key that makes this filter to emit a IoHandler.messageReceived(IoSession, Object) event with a special message (SESSION_SECURED or SESSION_UNSECURED). This is a marker attribute, which means that you can put whatever as its value. (Boolean.TRUE is preferred.) By default, this filter doesn't emit any events related with SSL session flow control.


SESSION_SECURED

public static final SSLFilter.SSLFilterMessage SESSION_SECURED
A special message object which is emitted with a IoHandler.messageReceived(IoSession, Object) event when the session is secured and its USE_NOTIFICATION attribute is set.


SESSION_UNSECURED

public static final SSLFilter.SSLFilterMessage SESSION_UNSECURED
A special message object which is emitted with a IoHandler.messageReceived(IoSession, Object) event when the session is not secure anymore and its USE_NOTIFICATION attribute is set.

Constructor Detail

SSLFilter

public SSLFilter(javax.net.ssl.SSLContext sslContext)
Creates a new SSL filter using the specified SSLContext.

Method Detail

getSSLSession

public javax.net.ssl.SSLSession getSSLSession(org.apache.mina.common.IoSession session)
Returns the underlying SSLSession for the specified session.

Returns:
null if no SSLSession is initialized yet.

startSSL

public boolean startSSL(org.apache.mina.common.IoSession session)
                 throws javax.net.ssl.SSLException
(Re)starts SSL session for the specified session if not started yet. Please note that SSL session is automatically started by default, and therefore you don't need to call this method unless you've used TLS closure.

Returns:
true if the SSL session has been started, false if already started.
Throws:
javax.net.ssl.SSLException - if failed to start the SSL session

isSSLStarted

public boolean isSSLStarted(org.apache.mina.common.IoSession session)
Returns true if and only if the specified session is encrypted/decrypted over SSL/TLS currently. This method will start to retun false after TLS close_notify message is sent and any messages written after then is not goinf to get encrypted.


stopSSL

public org.apache.mina.common.WriteFuture stopSSL(org.apache.mina.common.IoSession session)
                                           throws javax.net.ssl.SSLException
Stops the SSL session by sending TLS close_notify message to initiate TLS closure.

Parameters:
session - the IoSession to initiate TLS closure
Throws:
javax.net.ssl.SSLException - if failed to initiate TLS closure
java.lang.IllegalArgumentException - if this filter is not managing the specified session

isUseClientMode

public boolean isUseClientMode()
Returns true if the engine is set to use client mode when handshaking.


setUseClientMode

public void setUseClientMode(boolean clientMode)
Configures the engine to use client (or server) mode when handshaking.


isNeedClientAuth

public boolean isNeedClientAuth()
Returns true if the engine will require client authentication. This option is only useful to engines in the server mode.


setNeedClientAuth

public void setNeedClientAuth(boolean needClientAuth)
Configures the engine to require client authentication. This option is only useful for engines in the server mode.


isWantClientAuth

public boolean isWantClientAuth()
Returns true if the engine will request client authentication. This option is only useful to engines in the server mode.


setWantClientAuth

public void setWantClientAuth(boolean wantClientAuth)
Configures the engine to request client authentication. This option is only useful for engines in the server mode.


getEnabledCipherSuites

public java.lang.String[] getEnabledCipherSuites()
Returns the list of cipher suites to be enabled when SSLEngine is initialized.

Returns:
null means 'use SSLEngine's default.'

setEnabledCipherSuites

public void setEnabledCipherSuites(java.lang.String[] cipherSuites)
Sets the list of cipher suites to be enabled when SSLEngine is initialized.

Parameters:
cipherSuites - null means 'use SSLEngine's default.'

getEnabledProtocols

public java.lang.String[] getEnabledProtocols()
Returns the list of protocols to be enabled when SSLEngine is initialized.

Returns:
null means 'use SSLEngine's default.'

setEnabledProtocols

public void setEnabledProtocols(java.lang.String[] protocols)
Sets the list of protocols to be enabled when SSLEngine is initialized.

Parameters:
protocols - null means 'use SSLEngine's default.'

onPreAdd

public void onPreAdd(org.apache.mina.common.IoFilterChain parent,
                     java.lang.String name,
                     org.apache.mina.common.IoFilter.NextFilter nextFilter)
              throws javax.net.ssl.SSLException
Specified by:
onPreAdd in interface org.apache.mina.common.IoFilter
Overrides:
onPreAdd in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

onPostAdd

public void onPostAdd(org.apache.mina.common.IoFilterChain parent,
                      java.lang.String name,
                      org.apache.mina.common.IoFilter.NextFilter nextFilter)
               throws javax.net.ssl.SSLException
Specified by:
onPostAdd in interface org.apache.mina.common.IoFilter
Overrides:
onPostAdd in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

onPreRemove

public void onPreRemove(org.apache.mina.common.IoFilterChain parent,
                        java.lang.String name,
                        org.apache.mina.common.IoFilter.NextFilter nextFilter)
                 throws javax.net.ssl.SSLException
Specified by:
onPreRemove in interface org.apache.mina.common.IoFilter
Overrides:
onPreRemove in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

sessionClosed

public void sessionClosed(org.apache.mina.common.IoFilter.NextFilter nextFilter,
                          org.apache.mina.common.IoSession session)
                   throws javax.net.ssl.SSLException
Specified by:
sessionClosed in interface org.apache.mina.common.IoFilter
Overrides:
sessionClosed in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

messageReceived

public void messageReceived(org.apache.mina.common.IoFilter.NextFilter nextFilter,
                            org.apache.mina.common.IoSession session,
                            java.lang.Object message)
                     throws javax.net.ssl.SSLException
Specified by:
messageReceived in interface org.apache.mina.common.IoFilter
Overrides:
messageReceived in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

messageSent

public void messageSent(org.apache.mina.common.IoFilter.NextFilter nextFilter,
                        org.apache.mina.common.IoSession session,
                        java.lang.Object message)
Specified by:
messageSent in interface org.apache.mina.common.IoFilter
Overrides:
messageSent in class org.apache.mina.common.IoFilterAdapter

filterWrite

public void filterWrite(org.apache.mina.common.IoFilter.NextFilter nextFilter,
                        org.apache.mina.common.IoSession session,
                        org.apache.mina.common.IoFilter.WriteRequest writeRequest)
                 throws javax.net.ssl.SSLException
Specified by:
filterWrite in interface org.apache.mina.common.IoFilter
Overrides:
filterWrite in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException

filterClose

public void filterClose(org.apache.mina.common.IoFilter.NextFilter nextFilter,
                        org.apache.mina.common.IoSession session)
                 throws javax.net.ssl.SSLException
Specified by:
filterClose in interface org.apache.mina.common.IoFilter
Overrides:
filterClose in class org.apache.mina.common.IoFilterAdapter
Throws:
javax.net.ssl.SSLException