+

Search Tips   |   Advanced Search

Configure single sign-on using trust association interceptor ++

Perform this task to enable single sign-on using trust association interceptor ++. The steps involve setting up trust association and creating the interceptor properties.

Although we can use SWAM by selecting the Use SWAM-no authenticated communication between servers option on the Authentication mechanisms and expiration panel, single sign-on (SSO) requires LTPA as the configured authentication mechanism.

Lightweight Third Party Authentication (LTPA) is the default authentication mechanism for WebSphere Application Server. We can configure LTPA prior to configuring single sign-on (SSO) by clicking Security > Global security > Authentication mechanisms and expiration.

To establish the trust association for the single sign-on, perform the following steps:

  1. From the console for WebSphere Application Server, click Security Global security .

  2. Under Web security, click Trust association.

  3. Click Enable Trust Association.

  4. Click Interceptors.

  5. Click com.ibm.ws.security.web.TAMTrustAssociationInterceptorPlus to use a WebSEAL interceptor. This interceptor is one of two WebSEAL interceptors that are supplied for the use. You choose to use this interceptor by supplying properties as described in the next step.

    WebSphere Application Server attempts to initialize both of these interceptors even if you only supplied properties for the com.ibm.ws.security.web.TAMTrustAssociationInterceptorPlus interceptor. As a result, messages AWXRB0008E and SECJ0384E can appear during initialization to indicate that the interceptor you did not choose has failed to initialize. This is normal processing and does not affect the initialization of the interceptor you did select. To inhibit the display of messages AWXRB0008E and SECJ0384E, we can delete the interceptor we do not want to use prior to beginning the initialization. We can add that interceptor back later if the environment changes.

  6. Click Custom Properties.

  7. Click New to enter the property name and value pairs. Ensure that the following parameters are set:

    the TAI custom properties.
    Option Description
    com.ibm.websphere.security.
    webseal.checkViaHeader
    We can configure TAI so that the via header can be ignored when validating trust for a request. Set this property to false if none of the hosts in the via header need to be trusted. When set to false we do not need to set the trusted host names and host ports properties. The only mandatory property to check when via header is false is com.ibm.websphere.security.webseal.loginId.

    The default value of the check via header property is false. When using Tivoli Access Manager plug-in for web servers, set this property to false.

    The via header is part of the standard HTTP header that records the server names the request that passed through.

    com.ibm.websphere.security.
    webseal.loginId
    The WebSEAL trusted user as created in Create a trusted user account in Tivoli Access Manager The format of the username is the short name representation. This property is mandatory. If it is not set in WebSphere Application Server, the TAI initialization fails.
    com.ibm.websphere.security.
    webseal.id
    A comma-separated list of headers that exists in the request. If all of the configured headers do not exist in the request, trust cannot be established. The default value for the ID property is iv-creds. Any other values set in WebSphere Application Server are added to the list along with iv-creds, separated by commas.
    com.ibm.websphere.security.
    webseal.hostnames
    Do not set this property if using Tivoli Access Manager Plug-in for Web Servers. The property specifies the host names (case sensitive) that are trusted and expected in the request header. Requests arriving from un-listed hosts might not be trusted. If the checkViaHeader property is not set or is set to false then the trusted host names property has no influence. If the checkViaHeader property is set to true, and the trusted host names property is not set, TAI initialization fails.
    com.ibm.websphere.security.
    webseal.ports
    Do not set this property if using Tivoli Access Manager plug-in for web servers. This property is a comma-separated list of trusted host ports. Requests that arrive from unlisted ports might not be trusted. If the checkViaHeader property is not set, or is set to false this property has no influence. If the checkViaHeader property is set to true, and the trusted host ports property is not set in WebSphere Application Server, the TAI initialization fails.
    com.ibm.websphere.security.
    webseal.viaDepth
    A positive integer that specifies the number of source hosts in the via header to check for trust. By default, every host in the via header is checked, and if any host is not trusted, trust cannot be established. The via depth property is used when only some of the hosts in the via header have to be trusted. The setting indicates the number of hosts required to be trusted.

    As an example, consider the following header:

      Via: HTTP/1.1 webseal1:7002, 1.1 webseal2:7001

    If the viaDepth property is not set, is set to 2 or is set to 0, and a request with the previous via header is received then both webseal1:7002 and webseal2:7001 need to be trusted. The following configuration applies:

    com.ibm.websphere.security.webseal.hostnames = webseal1,webseal2
    com.ibm.websphere.security.webseal.ports = 7002,7001

    If the via depth property is set to 1, and the previous request is received, then only the last host in the via header needs to be trusted. The following configuration applies:

      com.ibm.websphere.security.webseal.hostnames = webseal2 com.ibm.websphere.security.webseal.ports = 7001

    The viaDepth property is set to 0 by default, which means all of the hosts in the via header are checked for trust.

    com.ibm.websphere.security.
    webseal.ssoPwdExpiry
    After trust is established for a request, the single sign-on user password is cached, eliminating the need to have the TAI re-authenticate the single sign-on user with Tivoli Access Manager for every request. We can modify the cache timeout period by setting the single sign-on password expiry property to the required time in seconds. If the password expiry property is set to 0, the cached password never expires. The default value for the password expiry property is 600.
    com.ibm.websphere.security.
    webseal.ignoreProxy
    This property can be used to tell the TAI to ignore proxies as trusted hosts. If set to true the comments field of the hosts entry in the via header is checked to determine if a host is a proxy. Remember that not all proxies insert comments in the via header indicating that they are proxies. The default value of the ignoreProxy property is false. If the checkViaHeader property is set to false then the ignoreProxy property has no influence in establishing trust.
    com.ibm.websphere.security.
    webseal.configURL

    (dist)(zos) For the TAI to establish trust for a request, it requires that the SvrSslCfg run for the Java Virtual Machine on the Application Server and result in the creation of a properties file. If this properties file is not at the default URL, which is file://java.home/PdPerm.properties, the correct URL of the properties file must be set in the configuration URL property. If not set, and the SvrSslCfg-generated properties file is not in the default location, the TAI initialization fails. The default value for the config URL property is file://$WAS_HOME/java/jre/PdPerm.properties.

    (iseries) Set this property to profile_root/etc/pd/PolicyDirector/PDPerm.properties. For the TAI to establish trust for a request, it requires that a PDPerm.properties file exists in each node within the cell. Also, the correct URL of the properties file must be set in the config URL property. If not set or the PDPerm.properties file is not in the specified location, the TAI initialization fails. The PDPerm.properties file is part of the Tivoli Access Manager configuration for a node. To create the Tivoli Access Manager configuration, run the pdjrtecfg script and then the svrsslcfg script for each node in the cell. The PDPerm.properties file is created in the profile_root/etc/pd/PolicyDirector/ directory.

  8. Click OK.

  9. Save the configuration and log out.

  10. Restart WebSphere Application Server.


Related concepts

  • Trust associations


    Related tasks

  • Configure single sign-on capability with Tivoli Access Manager or WebSEAL
  • Integrate third-party HTTP reverse proxy servers