Securing WebLogic Server

      

Configuring SSL

Configuring SSL is an optional step; however, Oracle recommends SSL for production environments. The following sections describe how to configure SSL for WebLogic Server.

Notes: The following sections apply to WebLogic Server deployments that use the security features in this release of WebLogic Server as well as deployments that use Compatibility Security.

Note: All machines must be kept up to date with the current set of recommended patches from the operating system vendors.

 

SSL: An Introduction

Secure Sockets Layer (SSL) provides secure connections by allowing two applications connecting over a network to authenticate each other's identity and by encrypting the data exchanged between the applications. Authentication allows a server and optionally a client to verify the identity of the application on the other end of a network connection. Encryption makes data transmitted over the network intelligible only to the intended recipient.

SSL in WebLogic Server is an implementation of the SSL 3.0 and Transport Layer Security (TLS) 1.0 specifications.

WebLogic Server supports SSL on a dedicated listen port which defaults to 7002. To establish an SSL connection, a Web browser connects to WebLogic Server by supplying the SSL listen port and the HTTPs protocol in the connection URL, for example, https://myserver:7002.

Using SSL is computationally intensive and adds overhead to a connection. Avoid using SSL in development environments when it is not necessary. However, always use SSL in a production environment.

 

One-Way and Two-Way SSL

SSL can be configured one-way or two-way:

 

Setting Up SSL: Main Steps

To set up SSL:

  1. Obtain an identity (private key and digital certificates) and trust (certificates of trusted certificate authorities) for WebLogic Server. Use the digital certificates, private keys, and trusted CA certificates provided by the WebLogic Server kit, the CertGen utility, Sun Microsystem's keytool utility, or a reputable vendor such as Entrust or Verisign to perform this step.

  2. Store the identity and trust. Private keys and trusted CA certificates which specify identity and trust are stored in a keystore.

    This release of WebLogic Server supports private keys and trusted CA certificates stored in files, or in the WebLogic Keystore provider for the purpose of backward compatibility only.

  3. Configure the identity and trust keystores for WebLogic Server in the WebLogic Server Administration Console. See Configure Keystores in the Administration Console Online Help.

  4. Set SSL configuration options for the private key alias and password in the WebLogic Server Administration Console. Optionally, set configuration options that require the presentation of client certificates (for two-way SSL). See Configure SSL and Configure two-way SSL in the Administration Console Online Help.

To enable a WebLogic Server instance to use a FIPS-compliant (FIPS 140-2) crypto module in the server's SSL implementation, make sure that the server start script (for example, startWebLogic.cmd/sh) contains the following:

Note: FIPS 140-2 is a standard that describes U.S. Federal government requirements for sensitive, but unclassified use.

For information on configuring identity and trust for WebLogic Server, see Obtaining Private Keys, Digital Certificates, and Trusted Certificate Authorities and Storing Private Keys, Digital Certificates, and Trusted Certificate Authorities.

 

Using Host Name Verification

A host name verifier ensures the host name in the URL to which the client connects matches the host name in the digital certificate that the server sends back as part of the SSL connection. A host name verifier is useful when an SSL client (or a WebLogic Server acting as an SSL client) connects to an application server on a remote host. It helps to prevent man-in-the-middle attacks.

By default, WebLogic Server has host name verification enabled. As a function of the SSL handshake, WebLogic Server compares the common name in the SubjectDN in the SSL server's digital certificate with the host name of the SSL server used to initiate the SSL connection. If these names do not match, the SSL connection is dropped. The SSL client is the actual party that drops the SSL connection if the names do not match.

If anything other than the default behavior is desired, either turn off host name verification or configure a custom host name verifier. Turning off host name verification leaves WebLogic Server vulnerable to man-in-the-middle attacks. Oracle recommends leaving host name verification on in production environments.

In this release of WebLogic Server, the host name verification feature is updated so that if the host name in the certificate matches the local machine's host name, host name verification passes if the URL specifies localhost, 127.0.01, or the default IP address of the local machine.

For more information, see the following topics in the Administration Console Online Help:

 

Enabling SSL Debugging

SSL debugging provides more detailed information about the SSL events that occurred during an SSL handshake. The SSL debug trace displays information about:

Use the following command-line properties to enable SSL debugging:

-Dssl.debug=true -Dweblogic.StdoutDebugEnabled=true

You can include SSL debugging properties in the start script of the SSL server, the SSL client, and the Node Manager. For a Managed Server started by the Node Manager, specify this command-line argument on the Remote Start page for the Managed Server.

SSL debugging dumps a stack trace whenever an ALERT is created in the SSL process. The types and severity of the ALERTS are defined by the Transport Layer Security (TLS) specification.

The stack trace dumps information into the log file where the ALERT originated. Therefore, when tracking an SSL problem, you may need to enable debugging on both sides of the SSL connection (on both the SSL client or the SSL server). The log file contains detailed information about where the failure occurred. To determine where the ALERT occurred, confirm whether there is a trace message after the ALERT. An ALERT received after the trace message indicates the failure occurred on the peer. To determine the problem, you need to enable SSL debugging on the peer in the SSL connection.

When tracking an SSL problem, review the information in the log file to ensure:

Sev 1 type 0 is a normal close ALERT, not a problem.

 

SSL Session Behavior

WebLogic Server allows SSL sessions to be cached. Those sessions live for the life of the server.

Clients that use SSL sockets directly can control the SSL session cache behavior. The SSL session cache is specific to each SSL context. All SSL sockets created by SSL socket factory instances returned by a particular SSL context can share the SSL sessions.

Clients default to resuming sessions at the same IP address and port. Multiple SSL sockets that use the same host and port share SSL sessions by default, assuming the SSL sockets are using the same underlying SSL context.

Clients that are not configured to use SSL sessions must call setEnableSessionCreation(false) on the SSL socket to ensure that no SSL sessions are cached. This setting only controls whether an SSL session is added to the cache; it does not stop an SSL socket from finding an SSL session that was already cached. For example, SSL socket 1 caches the session, SSL socket 2 sets setEnableSessionCreation to false but it can still reuse the SSL session from SSL socket 1 because that session was put in the cache.

SSL sessions exist for the lifetime of the SSL context; they are not controlled by the lifetime of the SSL socket. Therefore, creating a new SSL socket and connecting to the same host and port used by a previous session can resume a previous session as long as you create the SSL socket using an SSL socket factory from the SSL context that has the SSL session in its cache.

By default, clients that use HTTPS URLs get a new SSL session for each URL because each URL uses a different SSL context and therefore SSL sessions can not be shared or reused. You can retrieve the SSL session by using the weblogic.net.http.HttpsClient class or the weblogic.net.http.HttpsURLConnection class. Clients can also resume URLs by sharing a SSLSocket Factory between them.

Session caching is maintained by the SSL context, which can be shared by threads. A single thread has access to the entire session cache, not just one SSL session, so multiple SSL sessions can be used and shared in a single (or multiple) thread.

The following command-line arguments are ignored:

 

Configuring RMI over IIOP with SSL

Use SSL to protect Internet Interop-Orb-Protocol (IIOP) connections to Remote Method Invocation (RMI) remote objects. SSL secures connections through authentication and encrypts the data exchanged between objects.

To use SSL to protect RMI over IIOP connections:

  1. Configure WebLogic Server to use SSL.

  2. Configure the client Object Request Broker (ORB) to use SSL. Refer to the product documentation for your client ORB for information about configuring SSL.

  3. Use the host2ior utility to print the WebLogic Server IOR to the console. The host2ior utility prints two versions of the interoperable object reference (IOR), one for SSL connections and one for non-SSL connections. The header of the IOR specifies whether or not the IOR can be used for SSL connections.

  4. Use the SSL IOR when obtaining the initial reference to the CosNaming service that accesses the WebLogic Server JNDI tree.

For more information about using RMI over IIOP, see Programming WebLogic RMI.

 

SSL Certificate Validation

WebLogic Server ensures that each certificate in a certificate chain was issued by a certificate authority. All X509 V3 CA certificates used with WebLogic Server must have the Basic Constraint extension defined as CA, thus ensuring that all certificates in a certificate chain were issued by a certificate authority. By default, any certificates for certificate authorities not meeting this criteria are rejected. This section describes the command-line argument that controls the level of certificate validation.

If WebLogic Server is booted with a certificate chain that will not pass the certificate validation, an information message is logged noting that clients could reject it.

 

Controlling the Level of Certificate Validation

By default WebLogic Server rejects any certificates in a certificate chain that do not have the Basic Constraint extension defined as CA. However, you may be using certificates that do not meet this requirement or you may want to increase the level of security to conform to the IETF RFC 2459 standard. Use the following command-line argument to control the level of certificate validation performed by WebLogic Server:

-Dweblogic.security.SSL.enforceConstraints=option

Table 12-1 describes the options for the command-line argument.

Table 12-1 Options for -Dweblogic.security.SSL.enforceConstraints
Option Description
strong or true Use this option to ensure that the Basic Constraints extension on the CA certificate is defined as CA. For example: -Dweblogic.security.SSL.enforceConstraints=strong or -Dweblogic.security.SSL.enforceConstraints=true By default, WebLogic Server performs this level of certificate validation.
strict Use this option to ensure the Basic Constraints extension on the CA certificate is defined as CA and set to critical. This option enforces the IETF RFC 2459 standard. For example: -Dweblogic.security.SSL.enforceConstraints=strict This option is not the default because a number of commercially available CA certificates do not conform to the IETF RFC 2459 standard.
off Use this option to turn off checking for the Basic Constraints extension. The rest of the certificate is still validated. For example: -Dweblogic.security.SSL.enforceConstraints=off Oracle does not recommend using this option in a production environment. Instead, purchase new CA certificates that comply with the IETF RFC 2459 standard. CA certificates from most commercial certificate authorities should work with the default strong option.

 

Accepting Certificate Policies in Certificates

WebLogic Server offers limited support for Certificate Policy Extensions in X.509 certificates. Use the weblogic.security.SSL.allowedcertificatepolicyids argument to provide a comma separated list of Certificate Policy IDs. When WebLogic Server receives a certificate with a critical Certificate Policies Extension, it verifies whether any Certificate Policy is on the list of allowed certificate policies and whether there are any unsupported policy qualifiers. This release of WebLogic Server supports Certification Practice Statement (CPS) Policy qualifiers and does not support User Notice qualifiers. A certificate is also accepted if it contains a special policy anyPolicy with the ID 2.5.29.32.0, which indicates that the CA does not wish to limit the set of policies for this certificate.

To enable acceptance of Certificate Policies, start WebLogic Server with the following argument: 

-Dweblogic.security.SSL.allowedcertificatepolicyids <identifier1>,<identifier2>,...

This argument should contain a comma-separated list of Certificate Policy identifiers for all the certificates with critical extensions that might be present in the certificate chain, back to the root certificate, in order for WebLogic Server to accept such a certificate chain.

 

Checking Certificate Chains

Use the WebLogic Server ValidateCertChain command-line utility to confirm whether an existing certificate chain will be rejected by WebLogic Server. The utility validates certificate chains from PEM files, PKCS-12 files, PKCS-12 keystores, and JKS keystores. A complete certificate chain must be used with the utility. The following is the syntax for the ValidateCertChain command-line utility: 

java utils.ValidateCertChain -file pemcertificatefilename

java utils.ValidateCertChain -pem pemcertificatefilename

java utils.ValidateCertChain -pkcs12store pkcs12storefilename

java utils.ValidateCertChain -pkcs12file pkcs12filename password

java utils.ValidateCertChain -jks alias storefilename [storePass]

Example of valid certificate chain: 

java utils.ValidateCertChain -pem zippychain.pem



Cert[0]: CN=zippy,OU=FOR TESTING

ONLY,O=MyOrganization,L=MyTown,ST=MyState,C=US



Cert[1]: CN=CertGenCAB,OU=FOR TESTING

ONLY,O=MyOrganization,L=MyTown,ST=MyState,C=US

Certificate chain appears valid

Example of invalid certificate chain: 

java utils.ValidateCertChain -jks mykey mykeystore



Cert[0]: CN=corba1,OU=FOR TESTING ONLY, O=MyOrganization,L=MyTown,ST=MyState,C=US

CA cert not marked with critical BasicConstraint indicating it is a CA

Cert[1]: CN=CACERT,OU=FOR TESTING ONLY, O=MyOrganization,L=MyTown,ST=MyState,C=US



Certificate chain is invalid

 

Using Certificate Lookup and Validation Providers

WebLogic Server SSL has built-in certificate validation. Given a set of trusted CAs, this validation:

You can use certificate lookup and validation (CLV) providers to perform additional validation on the certificate chain. In this release, WebLogic Server has added two CLV providers:

Alternatively, you can write a custom CertPathValidator to provide additional validation on the certificate chain. See CertPath Providers in Developing security providers for WebLogic Server.

 

How SSL Certificate Validation Works in WebLogic Server

Outbound SSL and two-way inbound SSL in a WebLogic Server instance receive certificate chains during the SSL handshake that must be validated. An example of two-way inbound SSL is a browser connecting to a Web application over HTTPS where the browser sends the client's certificate chain to the Web application. The inbound certificate validation setting is used for all two-way client certificate validation in the server.

Examples of WebLogic Server using outbound SSL (that is, acting as an SSL client) include:

Using the Administration Console or WLST, you can independently configure inbound and outbound SSL certificate validation using these SSLMBean attributes: InboundCertificateValidation and OutboundCertificateValidation.

Legal values for both attributes are:

See:

 

Troubleshooting Problems with Certificate Validation

If SSL communications that worked properly in a previous release of WebLogic Server start failing unexpectedly, the likely problem is that the certificate chain is failing the validation.

Determine where the certificate chain is being rejected, and decide whether to update the certificate chain with one that will be accepted, or change the setting of the -Dweblogic.security.SSL.enforceConstraints command-line argument.

To troubleshoot problems with certificates, use one of the following methods:

 

Using the nCipher JCE Provider with WebLogic Server

Java Cryptography Extension (JCE) providers are written using the application programming interfaces (APIs) in the JCE available in JDK 5.0. This type of provider is different from the providers written using the WebLogic Security service provider Interfaces (SSPIs). WebLogic Server does not provide a JCE provider by default.

SSL is a key component in the protection of resources available in Web servers. However, heavy SSL traffic can cause bottlenecks that affect the performance of Web servers. JCE providers like nCipher that use a hardware card for encryption offload SSL processing from Web servers, which frees the servers to process more transactions. They also provide strong encryption and cryptographic processes to preserve the integrity and secrecy of keys.

WebLogic Server supports the use of the following JCE providers:

To install the nCipher JCE provider:

  1. Install and configure the hardware for the nCipher JCE provider according to the product's documentation.

  2. Install the files for the nCipher JCE provider. The following files are required:

    • Jurisdiction policy files—The JDK installs these files by default but they are of limited export strength.

    • Certificate that signed the JAR file

      This step may have been performed as part of installing the hardware for nCipher JCE provider. In that case, verify that the files are correctly installed.

    • The JCE provider JAR files

      Choose an installation method for the files:

    • Install files as an extension. Copy the files to one of the following locations:

      JAVA_HOME/jre/lib/ext

      For example:

      BEA_HOME/jdk150_03/jre/lib/ext

    • Install files in the CLASSPATH of the server.

  3. Edit the Java security properties file (java.security) to add the nCipher JCE provider to the list of approved JCE providers for WebLogic Server. The Java security properties file is located in:

    JAVA_HOME/jre/lib/security/java.security

    Specify the nCipher JCE provider as:

    security.provider.n=com.ncipher.provider.km.mCipherKM

    where

    n specifies the preference order that determines the order in which providers are searched for requested algorithms when no specific provider is requested. The order is 1-based; 1 is the most preferred, followed by 2, and so on.

    The nCipher JCE provider must follow the RSA JCA provider in the security properties file. For example:

    security.provider.1=sun.security.provider.Sun

    security.provider.2=com.sun.rsajca.Provider

    security.provider.3=com.ncipher.provider.km.mCipherKM

  4. Boot WebLogic Server.

  5. To ensure the nCipher JCE provider is working properly, enable debugging according to the nCipher product documentation.

 

Specifying the Version of the SSL Protocol

WebLogic Server supports both the SSL V3.0 and TLS V1.0 protocols. When WebLogic Server is acting as an SSL server, the protocol that the client specifies as preferred in its client hello message. When WebLogic Server is acting as an SSL client, it specifies TLS1.0 as the preferred protocol in its SSL V2.0 client hello message, but can use SSL V3.0 as well, if that is the highest version that the SSL server on the other end supports. The peer must respond with an SSL V3.0 or TLS V1.0 message or the SSL connection is dropped.

While in most cases the SSL V3.0 protocol is acceptable some circumstances (compatibility, SSL performance, and environments with maximum security requirements) make the TLS V1.0 protocol more desirable. The weblogic.security.SSL.protocolVersion command-line argument lets you specify which protocol is used for SSL connections.

The SSL V3.0 and TLS V1.0 protocols can not be interchanged. Only use the TLS V1.0 protocol if you are certain all desired SSL clients are capable of using the protocol.

The following command-line argument can be specified so that WebLogic Server supports only SSL V3.0 or TLS V1.0 connections: