23.1.1 Ensuring the Most Secure JRE

Before the browser plug-in software attempts to run a RIA, it verifies that the JRE version is at or above the security baseline for that family and that the age of the JRE is recent. If the JRE is determined to be below the security baseline, or if unable to verify the baseline and the current date is past the JRE Expiration Date, additional security warnings are displayed, or in some cases, the RIA is blocked. If the RIA is not automatically blocked, the user has the option to block the RIA, to continue running the RIA, or to go to java.com to download the latest release. The JRE expiration date can be found in the release notes for JDK Update releases starting with JDK 7u21.

23.1.2 JRE Expiration Date

The JRE relies on periodic checks with an Oracle Server to determine if the JRE is still considered up-to-date with all of the available security fixes (above the security baseline). From the 7u10 release onwards, all JREs contain a hard-coded expiration date. The expiration date is calculated to end after the scheduled release of the next Critical Patch Update.

JREs that are unable to contact Oracle Servers for an extended period of time now offer additional protection after a reasonable period and do not continue to behave as if they were up-to-date with regard to security fixes.

To test what happens when the JRE falls below the security baseline or expires, see Section 23.1.2.1, "Testing a JRE Below the Security Baseline" and Section 23.1.2.2, "Testing an Expired JRE".

23.1.3 Disabling Java in the Browser

If you prefer to completely disable access to Java through the browser, de-select the Enable Java content in the browser option in the Java Control Panel under the Security tab. See Section 20.4, "Security" for information.

If you do not need to run Java through a browser, consider installing the Server JRE, which does not contain the Java Plug-In. See Server JRE (Java SE Runtime Environment) 7 Downloads for information.

23.1.4 Setting the Security Level

Note: These settings affect all browsers that use Oracle's Java browser plug-in. They do not affect stand-alone applications.

The Security tab of the Java Control Panel contains a Security Level setting that controls the restrictions placed on any RIA that is run from the web. The user can select a level of High or Very High. This setting determines if a RIA is allowed to run and if so, the warnings you must accept before the RIA is started. The warnings contain information about the signing status of the RIA, the location of the RIA, and whether the RIA is requesting enhanced permissions to run outside the security sandbox.

At the Very High setting, only RIAs that are signed with a valid certificate that is located in the Signer CA keystore, and include the Permissions attribute in the manifest for the main JAR file are allowed to run with security prompts. At the High setting, RIAs that are signed with a valid certificate that is located in the Signer CA keystore, and include the Permissions attribute in the manifest for the main JAR file are allowed to run with security prompts. Applications are also allowed to run with security prompts when the revocation status of the certificate cannot be checked. For more information on security levels, see Section 20.4, "Security."

The default security level is High.

The ability to run applications is also affected by the settings described in Section 23.1.5, "Security Options for a Secure Execution Environment."

23.1.5 Security Options for a Secure Execution Environment

The following options are available in the Advanced tab of the Java Control Panel to set the behavior when a RIA is started:

• Allow user to grant permissions to signed content

• Show sandbox warning banner

• Allow user to accept JNLP security requests

• Don't prompt for client certificate selection when no certificates or only one exists

• Warn if site certificate does not match hostname

• Show site certificate even if it is valid

See Section 20.5, "Advanced" for more information on advanced options.

23.1.6 Install Options

Starting in the JDK 7u10 release, arguments for command line installation are available for setting the security level for Java in the browser. Admin privileges are required to install the JRE.

• On installation, the WEB_JAVA argument has the following effect:

  • WEB_JAVA=1 enables Java in the browser

  • WEB_JAVA=0 disables Java in the browser

• On installation, the WEB_JAVA_SECURITY_LEVEL argument has the following effect:

  • WEB_JAVA_SECURITY_LEVEL=VH sets the security level to very high

  • WEB_JAVA_SECURITY_LEVEL=H sets the security level to high

After installation of the JRE, you can check the Java Control Panel to verify that the security level settings are correct.

23.1.7 RIAs with Mixed Code

This information also applies to RIAs that contain calls between privileged code and sandbox code. For more information, see Chapter 27, "Mixing Privileged Code and Sandbox Code."

23.4.1 Internet Explorer keystore support

On Windows, browser keystore is supported through Internet Explorer. Certificates and keys in Internet Explorer are automatically recognized by Java Plug-in and Java Web Start when Java and JavaFX applications are deployed on Windows.

This feature is supported only with Internet Explorer 5.0 or higher.

23.4.2 Mozilla keystore support

On Linux and Solaris, browser keystore is supported through Mozilla. Certificates and keys in Mozilla are recognized by Java Plug-in and Java Web Start when Java and JavaFX applications are deployed on Linux and Solaris.

Support for Mozilla keystore requires a Mozilla library called JSS (Network Security Services for Java). By default, JSS is a separate component that does not ship with Mozilla -- it is the responsibility of the deployer to install JSS with Mozilla. Java Plug-in and Java Web Start enable the Mozilla keystore support after JSS is deployed.

This feature is supported only with Mozilla 1.4 or higher and JSS 3.2 or higher, assuming both Mozilla and JSS are compiled using the same compiler on the same platform.

23.4.3 Installing JSS with Mozilla

To install on Windows, follow these steps:

1. Create jss directory under Mozilla's installed directory.

2. Copy JSS JAR file into the jss directory.

3. Copy JSS native library DLL into Mozilla's installed directory.

To install on Solaris or Linux, follow these steps:

1. Create jss directory under Mozilla's installed directory.

2. Copy JSS JAR file into the jss directory.

3. Copy JSS native library .so into Mozilla's installed directory.

4. Set environment variable MOZILLA_HOME to Mozilla's installed directory in Mozilla's launch script.

5. Change environment variable LD_LIBRARY_PATH to include Mozilla's installed directory in Mozilla's launch script.

23.5.1 Dialog Contents

Beginning with the 7u21 release, users are notified when a RIA is launched with a security prompt similar to the following screen shot.

Figure 23-1 Security Dialog for a Trusted Application

Description of "Figure 23-1 Security Dialog for a Trusted Application"

Depending on the RIA, the security prompt shows the following information:

• Name of the RIA, or notification that the application is unsigned.

  The name that is shown is the value of the Application-Name attribute in the JAR file manifest. If the Application-Name attribute is not present, the value for the Main-Class attribute is used. If neither attribute is present in the manifest, no title is shown in the security prompts. Titles are not shown for unsigned RIAs. See Section 26.3, "Application-Name Attribute" for information.

• Warning when an out-of-date JRE is being used.

  For enterprises that manage the update process of user's systems, the deployment property deployment.expiration.check.enabled can be set to suppress the warnings for out-of-date JREs. See Chapter 21, "Deployment Configuration File and Properties" for information.

• Information about the publisher.

  If the application is self-signed or signed by an unknown authority, the publisher is shown as UNKNOWN.

• Warnings about the certificate.

  If the certificate is expired, revoked, or the server that tracks which certificates were revoked cannot be accessed, the prompt shows a warning. A warning is also shown if the certificate is not valid until a future date.

• Location from which the application is accessed.

  The value is either a URL for applications that are accessed from a website, or a directory for applications that are accessed from a local drive.

• Level of access required by the application.

  Limited access restricts the application to the security sandbox, unrestricted access provides the application with access to resources on the user's system.

• Warning about missing JAR file manifest attributes.

  JAR file manifest attributes are available to provide additional protection for an application. The warning indicates that the manifest is missing a recommended attribute. See Chapter 26, "JAR File Manifest Attributes for Security" for information.

• For unsigned or self-signed applications, a checkbox that the user must select before the Run button is enabled.

• Option to not show the prompt again.

  For signed RIAs, future prompts for this RIA and RIAs from the same location that are signed with the same certificate can be turned off. If the RIA is a sandbox application, then the prompt is turned off only for other sandbox applications that are signed with the same certificate. When shown, click Show Options to access the option to turn off the prompt.

  Prompts that were previously hidden can be restored through a button on the Security tab of the Java Control Panel. See Section 20.4.4, "Restore Security Prompts" for information.

• Buttons to Run the RIA, Cancel the RIA, and when a JRE is out of date, to Update to the latest JRE.

For a description and examples of the security prompts, see "What should I do when I see a security prompt from Java?" on java.com.

23.5.2 Improving the User Experience

The best experience for the user is when the RIA is restricted to the security sandbox and is signed with a current certificate from a trusted certificate authority. Clicking Run is all that is needed from the user to run the RIA.

As conditions become less secure, warning messages become stronger, and in some cases, more action is needed by the user, as described for the following situations:

• If the RIA is signed with a certificate from a trusted certificate authority, but requires unrestricted access to the user's system, the prompt warns the users about the risk of running the RIA. Clicking Run starts the RIA.

• If the RIA is signed with a certificate and the revocation status of the certificate cannot be checked, the prompt provides stronger warnings about the risk of running the RIA. The user must select the option to accept the risk, which enables the Run button, then click Run to run the RIA.

• Additional warnings are shown in some cases, such as when sandbox code attempts to access privileged code, or a RIA attempts to access resources that it does not have permission to access. These warnings require additional responses from the user.

For guidelines on deploying your RIA, see Deployment Best Practices in the Java Tutorial. For information on how the deployment of RIAs is handled, see Chapter 24, "Rich Internet Application Deployment Process.".

23.5.3 Java Control Panel Settings That Affect the Dialogs Shown

The Java Control Panel can be used to set options that are related to the security prompts. The Security tab provides an option to block Java content from running in a browser. The Security Level setting determines if the applet is automatically blocked and what level of prompting the user receives if the RIA is not blocked. See Section 20.4, "Security" for more information.

The Advanced tab provides options for managing RIAs:

• Secure Execution Environment options provide control for allowing or prohibiting users from granting privileges. If the user is not allowed to grant privileges, the security prompt is not shown and the app or features of the app are blocked.

• Mixed code security verification options provide control for showing or hiding prompts that warn of mixed code. If the prompts are hidden, some features might be blocked without any notice to the user.

See Section 20.5, "Advanced" for more information.