Package org.apache.mina.filter.ssl

Class SslFilter

  • All Implemented Interfaces:
    IoFilter
    public class SslFilter
extends 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). If you don't want the handshake procedure to start immediately, please specify false as autoStart parameter in the constructor.

    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.

    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 temporarily.
        // 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;
    }
 }

    • Field Detail

      • LOGGER

        private static final org.slf4j.Logger LOGGER
        The logger

      • SSL_SESSION

        public static final AttributeKey SSL_SESSION
        A session attribute key that stores underlying SSLSession for each session.

      • DISABLE_ENCRYPTION_ONCE

        public static final AttributeKey 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.

      • PEER_ADDRESS

        public static final AttributeKey PEER_ADDRESS
        A session attribute key that should be set to an InetSocketAddress. Setting this attribute causes SSLContext.createSSLEngine(String, int) to be called passing the hostname and port of the InetSocketAddress to get an SSLEngine instance. If not set SSLContext.createSSLEngine() will be called.
        Using this feature SSLSession objects may be cached and reused when in client mode.
        See Also:
        SSLContext.createSSLEngine(String, int)

      • NEXT_FILTER

        private static final AttributeKey NEXT_FILTER
        An attribute containing the next filter

      • SSL_HANDLER

        private static final AttributeKey SSL_HANDLER

      • sslContext

        final javax.net.ssl.SSLContext sslContext
        The SslContext used

      • autoStart

        private final boolean autoStart
        A flag used to tell the filter to start the handshake immediately

      • START_HANDSHAKE

        public static final boolean START_HANDSHAKE
        A flag used to determinate if the handshake should start immediately
        See Also:
        Constant Field Values

      • CLIENT_HANDSHAKE

        public static final boolean CLIENT_HANDSHAKE
        A flag used to determinate if the handshake should wait for the client to initiate the handshake
        See Also:
        Constant Field Values

      • client

        private boolean client

      • needClientAuth

        private boolean needClientAuth

      • wantClientAuth

        private boolean wantClientAuth

      • identificationAlgorithm

        private java.lang.String identificationAlgorithm

      • enabledCipherSuites

        private java.lang.String[] enabledCipherSuites

      • enabledProtocols

        private java.lang.String[] enabledProtocols

    • Constructor Detail

      • SslFilter

        public SslFilter​(javax.net.ssl.SSLContext sslContext)
        Creates a new SSL filter using the specified SSLContext. The handshake will start immediately after the filter has been added to the chain.
        Parameters:
        sslContext - The SSLContext to use

      • SslFilter

        public SslFilter​(javax.net.ssl.SSLContext sslContext,
                 boolean autoStart)
        Creates a new SSL filter using the specified SSLContext. If the autostart flag is set to true, the handshake will start immediately after the filter has been added to the chain.
        Parameters:
        sslContext - The SSLContext to use
        autoStart - The flag used to tell the filter to start the handshake immediately

    • Method Detail

      • getSslSession

        public javax.net.ssl.SSLSession getSslSession​(IoSession session)
        Returns the underlying SSLSession for the specified session.
        Parameters:
        session - The current session
        Returns:
        null if no SSLSession is initialized yet.

      • startSsl

        public boolean startSsl​(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.
        Parameters:
        session - The session that will be switched to SSL mode
        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

      • getSessionInfo

        java.lang.String getSessionInfo​(IoSession session)
        An extended toString() method for sessions. If the SSL handshake is not yet completed, we will print (ssl) in small caps. Once it's completed, we will use SSL capitalized.

      • isSslStarted

        public boolean isSslStarted​(IoSession session)
        Parameters:
        session - the session we want to check
        Returns:
        true if and only if the specified session is encrypted/decrypted over SSL/TLS currently. This method will start to return false after TLS close_notify message is sent and any messages written after then is not going to get encrypted.

      • isSecured

        public boolean isSecured​(IoSession session)
        Parameters:
        session - the session we want to check
        Returns:
        true if and only if the conditions for isSslStarted(IoSession) are met, and the handhake has completed.

      • stopSsl

        public WriteFuture stopSsl​(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
        Returns:
        The Future for the initiated closure
        Throws:
        javax.net.ssl.SSLException - if failed to initiate TLS closure

      • 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.
        Parameters:
        clientMode - true when we are in client mode, false when in server mode

      • 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.
        Parameters:
        needClientAuth - A flag set when we need to authenticate the client

      • 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.
        Parameters:
        wantClientAuth - A flag set when we want to check the client authentication

      • getEndpointIdentificationAlgorithm

        public java.lang.String getEndpointIdentificationAlgorithm()
        Returns:
        the endpoint identification algorithm to be used when SSLEngine is initialized. null means 'use SSLEngine's default.'

      • setEndpointIdentificationAlgorithm

        public void setEndpointIdentificationAlgorithm​(java.lang.String identificationAlgorithm)
        Sets the endpoint identification algorithm to be used when SSLEngine is initialized.
        Parameters:
        identificationAlgorithm - null means 'use SSLEngine's default.'

      • getEnabledCipherSuites

        public java.lang.String[] getEnabledCipherSuites()
        Returns:
        the list of cipher suites to be enabled when SSLEngine is initialized. 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. 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​(IoFilterChain parent,
                     java.lang.String name,
                     IoFilter.NextFilter nextFilter)
              throws javax.net.ssl.SSLException
        Executed just before the filter is added into the chain, we do :
        • check that we don't have a SSL filter already present
        • we update the next filter
        • we create the SSL handler helper class
        • and we store it into the session's Attributes
        Specified by:
        onPreAdd in interface IoFilter
        Overrides:
        onPreAdd in class IoFilterAdapter
        Parameters:
        parent - the parent who called this method
        name - the name assigned to this filter
        nextFilter - the IoFilter.NextFilter for this filter. You can reuse this object until this filter is removed from the chain.
        Throws:
        javax.net.ssl.SSLException

      • onPostAdd

        public void onPostAdd​(IoFilterChain parent,
                      java.lang.String name,
                      IoFilter.NextFilter nextFilter)
               throws javax.net.ssl.SSLException
        Description copied from class: IoFilterAdapter
        Invoked after this filter is added to the specified parent. Please note that this method can be invoked more than once if this filter is added to more than one parents. This method is not invoked before IoFilter.init() is invoked.
        Specified by:
        onPostAdd in interface IoFilter
        Overrides:
        onPostAdd in class IoFilterAdapter
        Parameters:
        parent - the parent who called this method
        name - the name assigned to this filter
        nextFilter - the IoFilter.NextFilter for this filter. You can reuse this object until this filter is removed from the chain.
        Throws:
        javax.net.ssl.SSLException

      • onPreRemove

        public void onPreRemove​(IoFilterChain parent,
                        java.lang.String name,
                        IoFilter.NextFilter nextFilter)
                 throws javax.net.ssl.SSLException
        Description copied from class: IoFilterAdapter
        Invoked before this filter is removed from the specified parent. Please note that this method can be invoked more than once if this filter is removed from more than one parents. This method is always invoked before IoFilter.destroy() is invoked.
        Specified by:
        onPreRemove in interface IoFilter
        Overrides:
        onPreRemove in class IoFilterAdapter
        Parameters:
        parent - the parent who called this method
        name - the name assigned to this filter
        nextFilter - the IoFilter.NextFilter for this filter. You can reuse this object until this filter is removed from the chain.
        Throws:
        javax.net.ssl.SSLException

      • isCloseNotify

        private boolean isCloseNotify​(java.lang.Object message)

      • initiateHandshake

        public void initiateHandshake​(IoSession session)
                       throws javax.net.ssl.SSLException
        Initiate the SSL handshake. This can be invoked if you have set the 'autoStart' to false when creating the SslFilter instance.
        Parameters:
        session - The session for which the SSL handshake should be done
        Throws:
        javax.net.ssl.SSLException - If the handshake failed

      • initiateHandshake

        private void initiateHandshake​(IoFilter.NextFilter nextFilter,
                               IoSession session)
                        throws javax.net.ssl.SSLException
        Throws:
        javax.net.ssl.SSLException

      • handleSslData

        private void handleSslData​(IoFilter.NextFilter nextFilter,
                           SslHandler sslHandler)
                    throws javax.net.ssl.SSLException
        Throws:
        javax.net.ssl.SSLException