Configuration Security - CAS

If you are running CAS in standalone mode without the presence of the configuration server, you can take advantage of built-in Jasypt functionality to decrypt sensitive CAS settings. Configuration security specified here should apply to all configuration files and settings loaded by CAS in all supported formats (i.e. properties, yaml, yml).

Jasypt supplies command-line tools useful for performing encryption, decryption, etc. In order to use the tools, you should download the Jasypt distribution. Once unzipped, you will find a jasypt-$VERSION/bin directory a number of bat|sh scripts that you can use for encryption/decryption operations (encrypt|decrypt).(bat|sh).

Encrypted settings need to be placed into CAS configuration files as:

1
cas.something.sensitive={cas-cipher}FKSAJDFGYOS8F7GLHAKERGFHLSAJ

You also need to instruct CAS to use the proper algorithm, decryption key and other relevant parameters when attempting to decrypt settings.

The following settings and properties are available from the CAS configuration catalog:

The configuration settings listed below are tagged as Required in the CAS configuration metadata. This flag indicates that the presence of the setting may be needed to activate or affect the behavior of the CAS feature and generally should be reviewed, possibly owned and adjusted. If the setting is assigned a default value, you do not need to strictly put the setting in your copy of the configuration, but should review it nonetheless to make sure it matches your deployment expectations.

The configuration settings listed below are tagged as Optional in the CAS configuration metadata. This flag indicates that the presence of the setting is not immediately necessary in the end-user CAS configuration, because a default value is assigned or the activation of the feature is not conditionally controlled by the setting value. In other words, you should only include this field in your configuration if you need to modify the default value or if you need to turn on the feature controlled by the setting.

  • cas.standalone.configuration-security.alg=
  • Algorithm to use when deciphering settings. Default algorithm is PBEWithMD5AndTripleDES.

    org.apereo.cas.configuration.model.core.config.standalone.StandaloneConfigurationSecurityProperties.

    How can I configure this property?

  • cas.standalone.configuration-security.initialization-vector=
  • An initialization vector is required for PBEWithDigestAndAES algorithms that aren't BouncyCastle. Enabling an initialization vector will break passwords encrypted without one. Toggling this value will make pre-existing non-PBEWithDigestAndAES encrypted passwords not work. For non-BouncyCastle PBEWithDigestAndAES algorithms that require an initialization vector, one will be used regardless of this setting since backwards compatibility with existing passwords using those algorithms is not an issue (since they didn't work in previous CAS versions). The default value is false so as not to break existing encrypted passwords. In general the use of an initialization vector will increase the encrypted text's length.

    org.apereo.cas.configuration.model.core.config.standalone.StandaloneConfigurationSecurityProperties.

    How can I configure this property?

  • cas.standalone.configuration-security.iterations=0
  • Total number of iterations to use when deciphering settings. Default value comes from Jasypt StandardPBEByteEncryptor#DEFAULT_KEY_OBTENTION_ITERATIONS

    org.apereo.cas.configuration.model.core.config.standalone.StandaloneConfigurationSecurityProperties.

    How can I configure this property?

  • cas.standalone.configuration-security.provider=
  • Security provider to use when deciphering settings. Leave blank for Java, BC for BouncyCastle.

    org.apereo.cas.configuration.model.core.config.standalone.StandaloneConfigurationSecurityProperties.

    How can I configure this property?

  • cas.standalone.configuration-security.psw=
  • Secret key/password to use when deciphering settings.

    org.apereo.cas.configuration.model.core.config.standalone.StandaloneConfigurationSecurityProperties.

    How can I configure this property?

    Configuration Metadata

    The collection of configuration properties listed in this section are automatically generated from the CAS source and components that contain the actual field definitions, types, descriptions, modules, etc. This metadata may not always be 100% accurate, or could be lacking details and sufficient explanations.

    Be Selective

    This section is meant as a guide only. Do NOT copy/paste the entire collection of settings into your CAS configuration; rather pick only the properties that you need. Do NOT enable settings unless you are certain of their purpose and do NOT copy settings into your configuration only to keep them as reference. All these ideas lead to upgrade headaches, maintenance nightmares and premature aging.

    YAGNI

    Note that for nearly ALL use cases, declaring and configuring properties listed here is sufficient. You should NOT have to explicitly massage a CAS XML/Java/etc configuration file to design an authentication handler, create attribute release policies, etc. CAS at runtime will auto-configure all required changes for you. If you are unsure about the meaning of a given CAS setting, do NOT turn it on without hesitation. Review the codebase or better yet, ask questions to clarify the intended behavior.

    Naming Convention

    Property names can be specified in very relaxed terms. For instance cas.someProperty, cas.some-property, cas.some_property are all valid names. While all forms are accepted by CAS, there are certain components (in CAS and other frameworks used) whose activation at runtime is conditional on a property value, where this property is required to have been specified in CAS configuration using kebab case. This is both true for properties that are owned by CAS as well as those that might be presented to the system via an external library or framework such as Spring Boot, etc.

    :information_source: Note

    When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

    Settings and properties that are controlled by the CAS platform directly always begin with the prefix cas. All other settings are controlled and provided to CAS via other underlying frameworks and may have their own schemas and syntax. BE CAREFUL with the distinction. Unrecognized properties are rejected by CAS and/or frameworks upon which CAS depends. This means if you somehow misspell a property definition or fail to adhere to the dot-notation syntax and such, your setting is entirely refused by CAS and likely the feature it controls will never be activated in the way you intend.

    Validation

    Configuration properties are automatically validated on CAS startup to report issues with configuration binding, specially if defined CAS settings cannot be recognized or validated by the configuration schema. Additional validation processes are also handled via Configuration Metadata and property migrations applied automatically on startup by Spring Boot and family.

    Indexed Settings

    CAS settings able to accept multiple values are typically documented with an index, such as cas.some.setting[0]=value. The index [0] is meant to be incremented by the adopter to allow for distinct multiple configuration blocks.

    :information_source: Usage
    The above settings may be passed to CAS at runtime using either OS environment variables, system properties or normal command-line arguments. Placing them in a CAS-owned configuration file will likely result in a dysfunctional setup. The encryption/decryption facade is put together early in the bootstrapping process before CAS has had a chance to load any configuration files. So bootstrapping the encryptor/decryptor components must happen at runtime so CAS gets a chance to initialize the right set of components before any configuration file can be loaded.

    Encryption and decryption support may also be used inside the CAS Command-line Shell.

    Troubleshooting

    To enable additional logging, modify the logging configuration file to add the following:

    1
    2
    3
    4
    
    <Logger name="org.apereo.cas.configuration" level="trace" additivity="false">
        <AppenderRef ref="casConsole"/>
        <AppenderRef ref="casFile"/>
    </Logger>