//
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=== Authentication Modules

Authentication Modules allow to specify how <<web-access,WA>> shall check the provided credentials against specific
technology or repository, in the context of a certain <<policies-authentication,Authentication Policy>>.

Several authentication modules are provided:

* Principal Authentication:
    ** https://apereo.github.io/cas/6.6.x/authentication/Database-Authentication.html[Database^]
    ** https://apereo.github.io/cas/6.6.x/authentication/JAAS-Authentication.html[JAAS^]
    ** https://apereo.github.io/cas/6.6.x/authentication/LDAP-Authentication.html[LDAP^]
    ** https://apereo.github.io/cas/6.6.x/authentication/SPNEGO-Authentication.html[SPNEGO^]
    ** https://apereo.github.io/cas/6.6.x/authentication/Syncope-Authentication.html[Syncope^]
    ** https://apereo.github.io/cas/6.6.x/authentication/X509-Authentication.html[X509^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-Generic-OpenID-Connect.html[OpenID Connect^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-OAuth20.html[OAuth2^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-SAML.htmll[SAML^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-Apple.html[Apple Signin^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-Azure-AD.html[Azure Active Directory^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-Google-OpenID-Connect.html[Google OpenID^]
    ** https://apereo.github.io/cas/6.6.x/integration/Delegate-Authentication-Keycloak.html[Keycloak^]
* MFA:
    ** https://apereo.github.io/cas/6.6.x/mfa/DuoSecurity-Authentication.html[Duo Security^]
    ** https://apereo.github.io/cas/6.6.x/mfa/FIDO-U2F-Authentication.html[Fido U2F^]
    ** https://apereo.github.io/cas/6.6.x/mfa/GoogleAuthenticator-Authentication.html[Google Authenticator^]

[TIP]
====
Custom authentication modules can be provided by implementing the
ifeval::["{snapshotOrRelease}" == "release"]
https://github.com/apache/syncope/blob/syncope-{docVersion}/common/am/lib/src/main/java/org/apache/syncope/common/lib/auth/AuthModuleConf.java[AuthModuleConf^]
endif::[]
ifeval::["{snapshotOrRelease}" == "snapshot"]
https://github.com/apache/syncope/blob/3_0_X/common/am/lib/src/main/java/org/apache/syncope/common/lib/auth/AuthModuleConf.java[AuthModuleConf^]
endif::[]
interface and extending appropriately the
ifeval::["{snapshotOrRelease}" == "release"]
https://github.com/apache/syncope/blob/syncope-{docVersion}/wa/bootstrap/src/main/java/org/apache/syncope/wa/bootstrap/WAPropertySourceLocator.java[WAPropertySourceLocator^]
endif::[]
ifeval::["{snapshotOrRelease}" == "snapshot"]
https://github.com/apache/syncope/blob/3_0_X/wa/bootstrap/src/main/java/org/apache/syncope/wa/bootstrap/WAPropertySourceLocator.java[WAPropertySourceLocator^]
endif::[]
class.
====

[NOTE]
Authentication Modules are dynamically translated into
https://apereo.github.io/cas/6.6.x/authentication/Configuring-Authentication-Components.html#authentication-handlers[CAS Authentication Handlers^].
