Shiro Authentication
CAS support handling the authentication event via Apache Shiro.
This feature is deprecated and is scheduled to be removed in the future.
Support is enabled by including the following dependency in the WAR overlay:
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<dependency>
<groupId>org.apereo.cas</groupId>
<artifactId>cas-server-support-shiro-authentication</artifactId>
<version>${cas.version}</version>
</dependency>
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implementation "org.apereo.cas:cas-server-support-shiro-authentication:${project.'cas.version'}"
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dependencyManagement {
imports {
mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
}
}
dependencies {
implementation "org.apereo.cas:cas-server-support-shiro-authentication"
}
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dependencies {
/*
The following platform references should be included automatically and are listed here for reference only.
implementation enforcedPlatform("org.apereo.cas:cas-server-support-bom:${project.'cas.version'}")
implementation platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
*/
implementation "org.apereo.cas:cas-server-support-shiro-authentication"
}
Shiro Configuration
Apache Shiro supports retrieving and checking roles and permissions for an authenticated subject. CAS exposes a modest configuration to enforce roles and permissions as part of the authentication, so that in their absence, the authentication may fail. While by default these settings are optional, you may configure roles and/or permissions for the given authentication handler to check their presence and report back.
The following settings and properties are available from the CAS configuration catalog:
cas.authn.shiro.password-encoder.encoding-algorithm=
The encoding algorithm to use such as
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cas.authn.shiro.password-encoder.type=NONE
Define the password encoder type to use. Type may be specified as blank or
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cas.authn.shiro.principal-transformation.groovy.location=
The location of the resource. Resources can be URLS, or files found either on the classpath or outside somewhere in the file system. In the event the configured resource is a Groovy script, specially if the script set to reload on changes, you may need to adjust the total number ofinotify instances. On Linux, you may need to add the following line to /etc/sysctl.conf: fs.inotify.max_user_instances = 256. You can check the current value via cat /proc/sys/fs/inotify/max_user_instances.
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cas.authn.shiro.location=
The location of the resource. Resources can be URLS, or files found either on the classpath or outside somewhere in the file system. In the event the configured resource is a Groovy script, specially if the script set to reload on changes, you may need to adjust the total number ofinotify instances. On Linux, you may need to add the following line to /etc/sysctl.conf: fs.inotify.max_user_instances = 256. You can check the current value via cat /proc/sys/fs/inotify/max_user_instances.
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cas.authn.shiro.password-encoder.character-encoding=UTF-8
The encoding algorithm to use such as 'UTF-8'. Relevant when the type used is
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cas.authn.shiro.password-encoder.hash-length=16
When used by
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cas.authn.shiro.password-encoder.secret=
Secret to use with
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cas.authn.shiro.password-encoder.strength=16
Strength or number of iterations to use for password hashing. Usually relevant when dealing with
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cas.authn.shiro.principal-transformation.blocking-pattern=
A regular expression that will be used against the username to match for blocking/forbidden values. If a match is found, an exception will be thrown and principal transformation will fail.
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cas.authn.shiro.principal-transformation.case-conversion=NONE
Indicate whether the principal identifier should be transformed into upper-case, lower-case, etc. Available values are as follows:
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cas.authn.shiro.principal-transformation.pattern=
A regular expression that will be used against the provided username for username extractions. On a successful match, the first matched group in the pattern will be used as the extracted username.
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cas.authn.shiro.principal-transformation.prefix=
Prefix to add to the principal id prior to authentication.
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cas.authn.shiro.principal-transformation.suffix=
Suffix to add to the principal id prior to authentication.
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cas.authn.shiro.name=
Name of the authentication handler.
Deprecation status is |
cas.authn.shiro.required-permissions=
Required permissions that should be authorized by Shiro.
Deprecation status is |
cas.authn.shiro.required-roles=
Required roles that should be authorized by Shiro.
Deprecation status is |
If you need to design your own password encoding scheme where the type is specified as a fully qualified Java class name, the structure of the class would be similar to the following:
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package org.example.cas;
import org.springframework.security.crypto.codec.*;
import org.springframework.security.crypto.password.*;
public class MyEncoder extends AbstractPasswordEncoder {
@Override
protected byte[] encode(CharSequence rawPassword, byte[] salt) {
return ...
}
}
If you need to design your own password encoding scheme where the type is specified as a path to a Groovy script, the structure of the script would be similar to the following:
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import java.util.*
byte[] run(final Object... args) {
def rawPassword = args[0]
def generatedSalt = args[1]
def logger = args[2]
def casApplicationContext = args[3]
logger.debug("Encoding password...")
return ...
}
Boolean matches(final Object... args) {
def rawPassword = args[0]
def encodedPassword = args[1]
def logger = args[2]
def casApplicationContext = args[3]
logger.debug("Does match or not ?");
return ...
Authentication handlers that generally deal with username-password credentials can be configured to transform the user id prior to executing the authentication sequence. Each authentication strategy in CAS provides settings to properly transform the principal. Refer to the relevant settings for the authentication strategy at hand to learn more.
Authentication handlers as part of principal transformation may also be provided a path to a Groovy script to transform the provided username. The outline of the script may take on the following form:
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String run(final Object... args) {
def providedUsername = args[0]
def logger = args[1]
return providedUsername.concat("SomethingElse")
}
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.
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. The validation process is on by default and can be skipped on startup using a special system
property SKIP_CONFIG_VALIDATION that should be set to true. 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.
Sample shiro.ini that needs be placed on the classpath based on the example above:
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[main]
cacheManager = org.apache.shiro.cache.MemoryConstrainedCacheManager
securityManager.cacheManager = $cacheManager
[users]
casuser = Mellon, admin
[roles]
admin = system,admin,staff,superuser:*
Logging
To enable additional logging, configure the log4j configuration file to add the following levels:
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...
<Logger name="org.apache.shiro" level="debug" additivity="false">
<AppenderRef ref="console"/>
<AppenderRef ref="file"/>
</Logger>
...