Update config API for TLS to match DIP.

This modifes the Config API to talk about encryption rather than TLS, as
well as renaming the on/off and the tls auth config to EncryptionLevel and
TrustStrategy, respectively.

Author: jakewins

driver/src/main/java/org/neo4j/driver/internal/connector/socket/SSLContextFactory.java

@@ -27,35 +27,34 @@
 import javax.net.ssl.TrustManagerFactory;
 
 import org.neo4j.driver.v1.Config;
+import org.neo4j.driver.v1.exceptions.ClientException;
+import org.neo4j.driver.internal.spi.Logger;
 
 import static org.neo4j.driver.internal.util.CertificateTool.loadX509Cert;
 
 class SSLContextFactory
 {
-
     private final String host;
     private final int port;
-    private final Config.TlsAuthenticationConfig authConfig;
+    private final Config.TrustStrategy authConfig;
+    private final Logger logger;
 
-    SSLContextFactory( String host, int port, Config.TlsAuthenticationConfig authConfig )
+    SSLContextFactory( String host, int port, Config.TrustStrategy authConfig, Logger logger )
     {
         this.host = host;
         this.port = port;
         this.authConfig = authConfig;
+        this.logger = logger;
     }
 
     public SSLContext create()
             throws GeneralSecurityException, IOException
     {
         SSLContext sslContext = SSLContext.getInstance( "TLS" );
+        TrustManager[] trustManagers;
 
-        // TODO Do we also want the server to verify the client's cert, a.k.a mutual authentication?
-        // Ref: http://logicoy.com/blogs/ssl-keystore-truststore-and-mutual-authentication/
-        KeyManager[] keyManagers = new KeyManager[0];
-        TrustManager[] trustManagers = null;
-
-        if ( authConfig.isFullAuthEnabled() )
-        {
+        switch ( authConfig.strategy() ) {
+        case TRUST_SIGNED_CERTIFICATES:
             // A certificate file is specified so we will load the certificates in the file
             // Init a in memory TrustedKeyStore
             KeyStore trustedKeyStore = KeyStore.getInstance( "JKS" );
@@ -68,13 +67,15 @@ public SSLContext create()
             TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance( "SunX509" );
             trustManagerFactory.init( trustedKeyStore );
             trustManagers = trustManagerFactory.getTrustManagers();
-        }
-        else
-        {
-            trustManagers = new TrustManager[]{new TrustOnFirstUseTrustManager( host, port, authConfig.certFile() )};
+            break;
+        case TRUST_ON_FIRST_USE:
+            trustManagers = new TrustManager[]{new TrustOnFirstUseTrustManager( host, port, authConfig.certFile(), logger )};
+            break;
+        default:
+            throw new ClientException( "Unknown TLS authentication strategy: " + authConfig.strategy().name() );
         }
 
-        sslContext.init( keyManagers, trustManagers, null );
+        sslContext.init( new KeyManager[0], trustManagers, null );
         return sslContext;
     }
 }

driver/src/main/java/org/neo4j/driver/internal/connector/socket/SocketClient.java

@@ -179,15 +179,22 @@ public static ByteChannel create( String host, int port, Config config, Logger l
             soChannel.setOption( StandardSocketOptions.SO_KEEPALIVE, true );
             soChannel.connect( new InetSocketAddress( host, port ) );
 
-            ByteChannel channel = null;
+            ByteChannel channel;
 
-            if( config.isTlsEnabled() )
+            switch ( config.encryptionLevel() )
             {
-                channel = new SSLSocketChannel( host, port, soChannel, logger, config.tlsAuthConfig() );
+            case REQUIRED:
+            {
+                channel = new TLSSocketChannel( host, port, soChannel, logger, config.trustStrategy() );
+                break;
             }
-            else
+            case REJECTED:
             {
                 channel = new AllOrNothingChannel( soChannel );
+                break;
+            }
+            default:
+                throw new ClientException( "Unknown TLS Level: " + config.encryptionLevel() );
             }
 
             if( logger.isTraceEnabled() )

driver/src/main/java/org/neo4j/driver/internal/connector/socket/SocketConnector.java

@@ -30,16 +30,19 @@
 
 public class SocketConnector implements Connector
 {
+    public static final String SCHEME = "bolt";
+    public static final int DEFAULT_PORT = 7687;
+
     @Override
     public boolean supports( String scheme )
     {
-        return scheme.equals( Config.SCHEME );
+        return scheme.equals( SCHEME );
     }
 
     @Override
     public Connection connect( URI sessionURI, Config config ) throws ClientException
     {
-        int port = sessionURI.getPort() == -1 ? Config.DEFAULT_PORT : sessionURI.getPort();
+        int port = sessionURI.getPort() == -1 ? DEFAULT_PORT : sessionURI.getPort();
         SocketConnection conn = new SocketConnection( sessionURI.getHost(), port, config );
         conn.init( "bolt-java-driver/" + Version.driverVersion() );
         return conn;
@@ -48,6 +51,6 @@ public Connection connect( URI sessionURI, Config config ) throws ClientExceptio
     @Override
     public Collection<String> supportedSchemes()
     {
-        return Collections.singletonList( Config.SCHEME );
+        return Collections.singletonList( SCHEME );
     }
 }

driver/src/main/java/org/neo4j/driver/internal/connector/socket/SSLSocketChannel.java renamed to driver/src/main/java/org/neo4j/driver/internal/connector/socket/TLSSocketChannel.java

@@ -32,14 +32,14 @@
 
 import org.neo4j.driver.internal.spi.Logger;
 import org.neo4j.driver.internal.util.BytePrinter;
-import org.neo4j.driver.v1.Config.TlsAuthenticationConfig;
+import org.neo4j.driver.v1.Config.TrustStrategy;
 import org.neo4j.driver.v1.exceptions.ClientException;
 
 import static javax.net.ssl.SSLEngineResult.HandshakeStatus.FINISHED;
 import static javax.net.ssl.SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING;
 
 /**
- * A blocking SSL socket channel.
+ * A blocking TLS socket channel.
  *
  * When debugging, we could enable JSSE system debugging by setting system property:
  * {@code -Djavax.net.debug=all} to value more information about handshake messages and other operations underway.
@@ -49,7 +49,7 @@
  * http://docs.oracle.com/javase/1.5.0/docs/guide/security/jsse/JSSERefGuide.html#SSLENG
  * http://docs.oracle.com/javase/7/docs/api/javax/net/ssl/SSLEngine.html
  */
-public class SSLSocketChannel implements ByteChannel
+public class TLSSocketChannel implements ByteChannel
 {
     private final SocketChannel channel;      // The real channel the data is sent to and read from
     private final Logger logger;
@@ -64,25 +64,25 @@ public class SSLSocketChannel implements ByteChannel
     private ByteBuffer plainIn;
     private ByteBuffer plainOut;
 
-    public SSLSocketChannel( String host, int port, SocketChannel channel, Logger logger,
-            TlsAuthenticationConfig authConfig )
+    public TLSSocketChannel( String host, int port, SocketChannel channel, Logger logger,
+                             TrustStrategy trustStrategy )
             throws GeneralSecurityException, IOException
     {
         logger.debug( "TLS connection enabled" );
         this.logger = logger;
         this.channel = channel;
         this.channel.configureBlocking( true );
 
-        sslContext =  new SSLContextFactory( host, port, authConfig ).create();
+        sslContext =  new SSLContextFactory( host, port, trustStrategy, logger ).create();
         createSSLEngine( host, port );
         createBuffers();
-        runSSLHandShake();
+        runHandshake();
         logger.debug( "TLS connection established" );
     }
 
     /** Used in internal tests only */
-    SSLSocketChannel( SocketChannel channel, Logger logger, SSLEngine sslEngine,
-            ByteBuffer plainIn, ByteBuffer cipherIn, ByteBuffer plainOut, ByteBuffer cipherOut )
+    TLSSocketChannel( SocketChannel channel, Logger logger, SSLEngine sslEngine,
+                      ByteBuffer plainIn, ByteBuffer cipherIn, ByteBuffer plainOut, ByteBuffer cipherOut )
             throws GeneralSecurityException, IOException
     {
         logger.debug( "Testing TLS buffers" );
@@ -109,7 +109,7 @@ public SSLSocketChannel( String host, int port, SocketChannel channel, Logger lo
      *
      * @throws IOException
      */
-    private void runSSLHandShake() throws IOException
+    private void runHandshake() throws IOException
     {
         sslEngine.beginHandshake();
         HandshakeStatus handshakeStatus = sslEngine.getHandshakeStatus();

driver/src/main/java/org/neo4j/driver/internal/connector/socket/TrustOnFirstUseTrustManager.java

@@ -24,24 +24,26 @@
 import java.io.FileReader;
 import java.io.FileWriter;
 import java.io.IOException;
-import java.net.InetAddress;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
 import javax.net.ssl.X509TrustManager;
-import javax.xml.bind.DatatypeConverter;
+
+import org.neo4j.driver.internal.spi.Logger;
+import org.neo4j.driver.internal.util.BytePrinter;
 
 import static org.neo4j.driver.internal.util.CertificateTool.X509CertToString;
 
 /**
  * References:
  * http://stackoverflow.com/questions/6802421/how-to-compare-distinct-implementations-of-java-security-cert-x509certificate?answertab=votes#tab-top
  */
-
 class TrustOnFirstUseTrustManager implements X509TrustManager
 {
     /**
-     * A list of pairs (known_server, certificate) are stored in this file.
-     * When establishing a SSL connection to a new server, we will save the server's ip:port and its certificate in this
+     * A list of pairs (known_server certificate) are stored in this file.
+     * When establishing a SSL connection to a new server, we will save the server's host:port and its certificate in this
      * file.
      * Then when we try to connect to a known server again, we will authenticate the server by checking if it provides
      * the same certificate as the one saved in this file.
@@ -50,15 +52,15 @@ class TrustOnFirstUseTrustManager implements X509TrustManager
 
     /** The server ip:port (in digits) of the server that we are currently connected to */
     private final String serverId;
+    private final Logger logger;
 
     /** The known certificate we've registered for this server */
-    private String cert;
+    private String fingerprint;
 
-    TrustOnFirstUseTrustManager( String host, int port, File knownCerts ) throws IOException
+    TrustOnFirstUseTrustManager( String host, int port, File knownCerts, Logger logger ) throws IOException
     {
-        String ip = InetAddress.getByName( host ).getHostAddress(); // localhost -> 127.0.0.1
-        this.serverId = ip + ":" + port;
-
+        this.logger = logger;
+        this.serverId = host + ":" + port;
         this.knownCerts = knownCerts;
         load();
     }
@@ -76,16 +78,16 @@ private void load() throws IOException
         }
 
         BufferedReader reader = new BufferedReader( new FileReader( knownCerts ) );
-        String line = null;
+        String line;
         while ( (line = reader.readLine()) != null )
         {
-            if ( (!line.trim().startsWith( "#" )) && line.contains( "," ) )
+            if ( (!line.trim().startsWith( "#" )) )
             {
-                String[] strings = line.split( "," );
+                String[] strings = line.split( " " );
                 if ( strings[0].trim().equals( serverId ) )
                 {
                     // load the certificate
-                    cert = strings[1].trim();
+                    fingerprint = strings[1].trim();
                     return;
                 }
             }
@@ -96,16 +98,17 @@ private void load() throws IOException
     /**
      * Save a new (server_ip, cert) pair into knownCerts file
      *
-     * @param cert
+     * @param fingerprint
      */
-    private void save( String cert ) throws IOException
+    private void saveTrustedHost( String fingerprint ) throws IOException
     {
-        this.cert = cert;
+        this.fingerprint = fingerprint;
 
+        logger.warn( "Adding %s as known and trusted certificate for %s.", fingerprint, serverId );
         createKnownCertFileIfNotExists();
 
         BufferedWriter writer = new BufferedWriter( new FileWriter( knownCerts, true ) );
-        writer.write( serverId + "," + this.cert );
+        writer.write( serverId + " " + this.fingerprint );
         writer.newLine();
         writer.close();
     }
@@ -126,15 +129,14 @@ public void checkServerTrusted( X509Certificate[] chain, String authType )
             throws CertificateException
     {
         X509Certificate certificate = chain[0];
-        byte[] encoded = certificate.getEncoded();
 
-        String cert = DatatypeConverter.printBase64Binary( encoded );
+        String cert = fingerprint( certificate );
 
-        if ( this.cert == null )
+        if ( this.fingerprint == null )
         {
             try
             {
-                save( cert );
+                saveTrustedHost( cert );
             }
             catch ( IOException e )
             {
@@ -146,7 +148,7 @@ public void checkServerTrusted( X509Certificate[] chain, String authType )
         }
         else
         {
-            if ( !this.cert.equals( cert ) )
+            if ( !this.fingerprint.equals( cert ) )
             {
                 throw new CertificateException( String.format(
                         "Unable to connect to neo4j at `%s`, because the certificate the server uses has changed. " +
@@ -156,21 +158,47 @@ public void checkServerTrusted( X509Certificate[] chain, String authType )
                         "in the file `%s`.\n" +
                         "The old certificate saved in file is:\n%sThe New certificate received is:\n%s",
                         serverId, serverId, knownCerts.getAbsolutePath(),
-                        X509CertToString( this.cert ), X509CertToString( cert ) ) );
+                        X509CertToString( this.fingerprint ), X509CertToString( cert ) ) );
             }
         }
     }
 
+    /**
+     * Calculate the certificate fingerprint - simply the SHA-1 hash of the DER-encoded certificate.
+     */
+    public static String fingerprint( X509Certificate cert ) throws CertificateException
+    {
+        try
+        {
+            MessageDigest md = MessageDigest.getInstance( "SHA-1" );
+            md.update( cert.getEncoded() );
+            return BytePrinter.compactHex( md.digest() );
+        }
+        catch( NoSuchAlgorithmException e )
+        {
+            // SHA-1 not available
+            throw new CertificateException( "Cannot use TLS on this platform, because SHA-1 message digest algorithm is not available: " + e.getMessage(), e );
+        }
+    }
+
     private File createKnownCertFileIfNotExists() throws IOException
     {
         if ( !knownCerts.exists() )
         {
             File parentDir = knownCerts.getParentFile();
             if( parentDir != null && !parentDir.exists() )
             {
-                parentDir.mkdirs();
+                if(!parentDir.mkdirs()) {
+                    throw new IOException( "Failed to create directories for the known hosts file in " + knownCerts.getAbsolutePath() + ". This is usually " +
+                                           "because you do not have write permissions to the directory. Try configuring the Neo4j driver to use a file " +
+                                           "system location you do have write permissions to." );
+                }
+            }
+            if(!knownCerts.createNewFile()) {
+                throw new IOException( "Failed to create a known hosts file at " + knownCerts.getAbsolutePath() + ". This is usually " +
+                                       "because you do not have write permissions to the directory. Try configuring the Neo4j driver to use a file " +
+                                       "system location you do have write permissions to." );
             }
-            knownCerts.createNewFile();
             BufferedWriter writer = new BufferedWriter( new FileWriter( knownCerts ) );
             writer.write( "# This file contains trusted certificates for Neo4j servers, it's created by Neo4j drivers." );
             writer.newLine();

driver/src/main/java/org/neo4j/driver/internal/logging/DevNullLogger.java

@@ -35,6 +35,12 @@ public void info( String message, Object... params )
 
     }
 
+    @Override
+    public void warn( String message, Object... params )
+    {
+
+    }
+
     @Override
     public void debug( String message, Object... params )
     {

driver/src/main/java/org/neo4j/driver/internal/logging/JULogger.java

@@ -48,6 +48,12 @@ public void info( String format, Object... params )
         delegate.log( Level.INFO, String.format( format, params ) );
     }
 
+    @Override
+    public void warn( String format, Object... params )
+    {
+        delegate.log( Level.WARNING, String.format( format, params ) );
+    }
+
     @Override
     public void debug( String format, Object... params )
     {

driver/src/main/java/org/neo4j/driver/internal/spi/Logger.java

@@ -24,6 +24,8 @@ public interface Logger
 
     void info( String message, Object... params );
 
+    void warn( String message, Object... params );
+
     void debug( String message, Object... params );
 
     void trace( String message, Object... params );