8/19/20151 Securing a Database Based on notes by Fei Li and Hong Li

8/19/20152 Topics  Securing the connections to the database: 1.SSL-tunneling between client machine and database machine 2.A secure JDBC driver  Securing the data within a database  Secure Thin JDBC Connection Sample

8/19/20153 JDBC Basics  JDBC is a Java API for executing SQL statements  JDBC makes it possible to do three things: 1.establish a connection with a database 2.send SQL statements 3.process the results.

8/19/20154 Securing a database  Two points of attack against a database –The connection between clients and database –The data in the database

8/19/20155 Securing the JDBC driver transmission  Approach 1: SSL-tunneling –Running a daemon on the client machine –Advantage: simplicity and performance –Disadvantage: not enough of authentication, esp. if the client machine is a shared or multi-user environment.  Approach 2: Proxy to JDBC drivers –developing a JDBC driver proxy –Advantage: provide more security –Disadvantage: much more complex

8/19/20156 SSL-Tunneling TunnelServer Database instance Database Machine TunnelServer Client Machine Client Application SQL request SQL response SQL request SSL Socket

8/19/20157 The SSL-Tunneling Approach  Two instances of the tunnel server, one on the client machine and the other on the database server machine  Each instance serves as a proxy.  Simplicity of encrypting the database connection by SSL-tunneling between the client application and the DBMS

8/19/20158 Query processing Client Machine Client application The JDBC client Client-side tunnel server Reads unencrypted data from the JDBC client; Write it encrypted to the database machine over SSL Database Machine Server-side tunnel server Reads the encrypted data from the client-side tunnel server; Sends it unencrypted to the DBMS over localhost Database server

8/19/20159 Response processing Client Machine Client-side tunnel server Reads encrypted data from the server-side tunnel server; Write it unencrypted to the JDBC client; Client application Database Machine Database server Sends query result to the tunnel server Server-side tunnel server Reads the query result from the DBMS over localhost; Sends it encrypted to the client-side tunnel server;

8/19/ The SSL-Tunneling Approach TunnelServer Database instance Database Machine TunnelServer Client Machine Client Application 3. SQL request 4. SQL response 6. SQL response 1. SQL request 2. Encrypted SQL request 5. Encrypted SQL response Assumption: Connections to localhost cannot be snooped. True or false?

8/19/ Example 1: The Tunnel Server  Two classes –TunnelServer –TunnelThread  TunnelServer class (p. 310) –Correction: client (mRemote == false) or the server (mRemote == true) public TunnelServer (String server, int appPort, int tunnelPort, boolean remote) { super(); mDestServer = server; mAppPort = appPort; mTunnelPort = tunnelPort; mRemote = remote; waitForConnections(); }

8/19/ Example1: The Tunnel Server  Get server socket, waiting for connections, and create two instances of TunnelThread. private void waitForConnections() { …… serverSocket = getServerSocket(); while (mListening) { try { logMessage("Waiting for connections."); srcSocket = serverSocket.accept(); …… destSocket = connect(); logMessage("Connected to remote server at " + destSocket.getInetAddress() + "."); fromClient = getTunnelThread("fromClient"); toClient = getTunnelThread("toClient"); ……

8/19/ Example1: The Tunnel Server  The TunnelThread class (p ) –Forwarding requests and responds /** Creates new TunnelThread name a name for this thread*/ public TunnelThread(String name) { super(name); setDaemon(true); } /**Default constructor -- create a tunnel thread with a default name*/ public TunnelThread( ) { super( ); setDaemon(true); } public void run ( ) { }

8/19/ Example1: The Tunnel Server  Run the Tunnel Server with JDBC 1.Generate keystore/certificates for client and server  serverKeyStore, clientKeyStore (p.317) 2.Copy serverKeyStore to the database server; Start the tunnel server on the server side (database machine) 3.Copy clientKeyStore to the client machine; Start the tunnel server on the client side (client machine) (p.318) 4.Run a test application on the client machine

8/19/ Example1: The Tunnel Server  Create Keystore >keytool -genkey -keyalg RSA -keystore serverKeyStore >keytool -genkey -keyalg RSA -keystore clientKeyStore

8/19/ Example1: The Tunnel Server  Create Keystore –Export the certificates >keytool -export -keystore serverKeyStore -file server.cer >keytool -export -keystore clientKeyStore -file client.cer

8/19/ Example1: The Tunnel Server  Create Keystore –Import the certificates >keytool -import -file client.cer -alias client -keystore serverKeyStore >keytool -import -file server.cer -alias server -keystore clientKeyStore

8/19/ Example1: The Tunnel Server  Start the tunnel server on the server –Copy serverKeyStore TunnelServer.class, and TunnelThread.class to the database machine >java -Djavax.net.ssl.keyStore=serverKeyStore -Djavax.net.ssl.keyStorePassword=sps2020 -Djavax.net.ssl.trustStore=serverKeyStore com.isnetworks.crypto.net.TunnelServer localhost remote  Exercise: –Use the TunnelServer.java source code to trace the execution of the server-side TunnelServer and show its screen output.

8/19/ Example1: The Tunnel Server  Start the tunnel server on the client –Copy clientKeyStore TunnelServer.class, and TunnelThread.class to the clinet machine >java -Djavax.net.ssl.keyStore=clientKeyStore -Djavax.net.ssl.keyStorePassword=cps2020 -Djavax.net.ssl.trustStore=clientKeyStore com.isnetworks.crypto.net.TunnelServer diamond.rocks.uhcl.edu local

8/19/ Example1: The Tunnel Server  Run a test application on the client machine –Use JDBCTest.java –Set the JDBC driver (classes.zip) in the classpath DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver()); Connection conn = DriverManager.getConnection ( “username", “password");

8/19/ Example1: The Tunnel Server  Sample programs for running Tunnel Server on dcm.uhcl.edu (the client application) and diamond.rocks.uhcl.edu (the DBMS server): –TunnelServer.javaTunnelServer.java –TunnelThread.javaTunnelThread.java –JDBCTest.javaJDBCTest.java  Detailed instructions: instructions.docinstructions.doc

8/19/ Securing the JDBC Driver Transmission  Approach 2: Proxy to JDBC drivers –developing a JDBC driver proxy –Advantage: provide more security –Disadvantage: much more complex

8/19/ The JDBC Driver Proxy  Provide the encryption and authentication for many applications –Delegate all the calls to dynamically bound driver  Provide proxies to JDBC driver classes –Proxy design pattern in distributed computing  Use SSL for the connection –Encryption –Authentication later on

8/19/ The JDBC Driver Database Machine DB Secure JDBC Driver Proxy Database client (application server)

8/19/ The JDBC Driver  Client-Server communication –Server handles configuration, connections to the DB, and delegation of the JDBC calls –Client delegates all the connections to the server  Choose RMI as a network transport for communication –Have to add one more layer to the remote call –The diagram on p.321.

8/19/  Implementation –Delegate the common operations to an abstract super class. –Use a single remote class to pass any method call instead of creating an RMI proxy for each JDBC interface –Is a complex solution to a simple problem –Proxy pattern enables developer to add service The JDBC Driver

8/19/  Using the secure JDBC driver Detailed instructions for running the sample application: SecureDriver.rtfSecureDriver.rtf  Steps of Configuring the driver: 1.Generate the keys and certificates 2.Edit the SecureDriver_config.xml file 3.Create policy files for the server and client The JDBC Driver

8/19/  Edit the SecureDriver_config.xml file –Defines JDBC connection directly to the database from the secure driver  Create policy files –RMI requires that code run with a security manager –Add some special permissions to policy files –Server policy file The ability to connect to the database The ability to talk to the RMI registry The ability to receive a connection from a remote client The JDBC Driver

8/19/ The JDBC Driver  Connecting to the RMI server process: –The connect( ) method is called by DriverManager and connects to the RMI server process, which is where the actual JDBC connections reside.

8/19/ The JDBC Driver  Discussion: Can the application be modified to run without RMI? How?

8/19/ Securing Data in the Database  Protect the data in database –Database permission Should be set properly by the administrator –Read- or write-only database If it is well protected, highly controlled, and not often accessed Large online retailers use write-only database

8/19/ Securing data in the database  Protect the data in databases –Symmetric encryption Applications storing a secret key need to be completely safe –Asymmetric encryption Public key is used for encrypting the data in the DB Private key must be stored somewhere safe.  Disadvantage of encrypting data –Expensive –Remove some of the value of using a database

8/19/ Example3: Encrypting credit cards Credit Cards 3Xizmj2 Cg31C1l … Database (Stores encrypted credit card data) Finance client Decrypt Server One-way encrypt

8/19/ Encrypting credit cards CreditCardFactory -mPublicKey +createCreditCard() +findAllCreditCards() +findCreditCard() CreditCard -mAccountID -mCreditCardNumber +CreditCard() +getAccountID() +getCreditCardNumber() DatabaseOperations +getAllCreditCardAccountIDs() +loadCreditCardDBO() +store(creditCardDBO:CreditCardDBO) CrditCardDBO -mAccountID -mEncryptedCCNumber -mEncryptedSessionKey +CreditCardDBO() +getAccountID() +getEncryptedCCNumber() +getEncryptedSessionKey()

8/19/ Encrypting credit cards  Testing the application – CreateTest.java –Create a credit card based on user-specified account ID and credit card number Create a Properties object from the file system Properties properties = new Properties(); FileInputStream fis = new FileInputStream(PROPERTIES_FILE); properties.load(fis); fis.close(); // Create the credit card CreditCardFactory factory = new CreditCardFactory(properties); CreditCard creditCard = factory.createCreditCard(id,ccNumber);

8/19/ Encrypting credit cards  Testing the application – ViewTest –Define the location of the keystore –Load the keystore to retrieve the private key private static final String KEYSTORE = "creditcardExample.ks"; …… // Load the keystore to retrieve the private key. String ksType = KeyStore.getDefaultType(); KeyStore ks = KeyStore.getInstance(ksType); FileInputStream fis = new FileInputStream(KEYSTORE); ks.load(fis,PASSWORD); fis.close(); PrivateKey privateKey = (PrivateKey)ks.getKey("mykey",PASSWORD);

8/19/ Secure Thin JDBC Connection  Oracle JDBC Thin Driver –The Oracle JDBC Thin driver is a 'Type IV' (native protocol, 100% Pure Java) implementation that complies with the JDBC 1.22 standard. –The JDBC Thin driver uses Java Sockets to connect directly to the Oracle Server –The JDBC Thin driver does not require Oracle software on the client side

8/19/ Secure Thin JDBC Connection  Encryption and integrity support –use Oracle Advanced Security data encryption and integrity features in your Java database applications – When using the Thin driver, the parameters are set through a Java properties file –Encryption is enabled or disabled based on a combination of the client-side encryption-level setting and the server-side encryption-level setting

8/19/ Secure Thin JDBC Connection  Get SecureThinDriver.jar to run the sample –Configuring Encryption Parameter Using Oracle Net Manager –Run the Application using JDeveloper Environment –Run the Application from JDK Environment

8/19/ Reference [1] JDBC Introduction [2] J. Garms and D. Somerfield. Professional Java Security [3] Secure Thin JDBC Connection iver/Readme.html [4] The status of HIPNS eding.htm [5] Improving Database Performance with Oracle8 ‚