OAuth Authentication

Allow CAS to act as an OAuth authentication provider. Please review the specification to learn more.

:information_source: CAS as OAuth Server

This page specifically describes how to enable OAuth identity provider server support for CAS. If you would like to have CAS act as an OAuth/OpenID client communicating with other providers (such as Google, Facebook, etc), see this page.

Actuator Endpoints

The following endpoints are provided by CAS:

oauthTokens
CAS endpoint3 operationsNot exposed by default
1

Turn the endpoint on and expose it over the web. One entry covers every operation. By default only info, health and status are exposed.

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management.endpoint.oauthTokens.access=UNRESTRICTED
management.endpoints.web.exposure.include=oauthTokens

Endpoints may be mapped to other paths. For example, to serve health at healthcheck:

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management.endpoints.web.path-mapping.health=healthcheck

Configuration

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-oauth-webflow</artifactId>
    <version>${cas.version}</version>
</dependency>
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implementation "org.apereo.cas:cas-server-support-oauth-webflow:${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-oauth-webflow"
}
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dependencies {
    /*
        The following platform references are included automatically and are listed 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-oauth-webflow"
}

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

cas.authn.oauth.access-token.crypto.encryption.keyThe encryption key is a string whose length is defined by the encryption key size setting.
no default
RequiredSpEL

The encryption key is a string whose length is defined by the encryption key size setting.

Type
String
Default
none
Defined by
EncryptionJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.access-token.crypto.signing.keyThe signing key is a string whose length is defined by the signing key size setting.
no default
RequiredSpEL

The signing key is a string whose length is defined by the signing key size setting.

Type
String
Default
none
Defined by
SigningJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.crypto.encryption.keyThe encryption key is a string whose length is defined by the encryption key size setting.
no default
RequiredSpEL

The encryption key is a string whose length is defined by the encryption key size setting.

Type
String
Default
none
Defined by
EncryptionJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.crypto.signing.keyThe signing key is a string whose length is defined by the signing key size setting.
no default
RequiredSpEL

The signing key is a string whose length is defined by the signing key size setting.

Type
String
Default
none
Defined by
SigningJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.session-replication.cookie.crypto.encryption.keyThe encryption key is a string whose length is defined by the encryption key size setting.
no default
RequiredSpEL

The encryption key is a string whose length is defined by the encryption key size setting.

Type
String
Default
none
Defined by
EncryptionJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.session-replication.cookie.crypto.signing.keyThe signing key is a string whose length is defined by the signing key size setting.
no default
RequiredSpEL

The signing key is a string whose length is defined by the signing key size setting.

Type
String
Default
none
Defined by
SigningJwtCryptoProperties
Supports
Spring Expression Language
cas.authn.oauth.access-token.create-as-jwtCreate access token as JWTs.
false

Create access token as JWTs.

Type
Boolean
Default
false
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.access-token.crypto.algThe signing/encryption algorithm to use.
no default

The signing/encryption algorithm to use.

Type
String
Default
none
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.access-token.crypto.enabledWhether crypto operations are enabled.
true

Whether crypto operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.access-token.crypto.encryption-enabledWhether crypto encryption operations are enabled.
true

Whether crypto encryption operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.access-token.crypto.encryption.key-sizeThe encryption key size.
512

The encryption key size.

Type
Integer
Default
512
Defined by
EncryptionJwtCryptoProperties
cas.authn.oauth.access-token.crypto.signing-enabledWhether crypto signing operations are enabled.
true

Whether crypto signing operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.access-token.crypto.signing.key-sizeThe signing key size.
512

The signing key size.

Type
Integer
Default
512
Defined by
SigningJwtCryptoProperties
cas.authn.oauth.access-token.crypto.strategy-typeControl the cipher sequence of operations.
ENCRYPT_AND_SIGN
Control the cipher sequence of operations. The accepted values are:
  • ENCRYPT_AND_SIGN: Encrypt the value first, and then sign.
  • SIGN_AND_ENCRYPT: Sign the value first, and then encrypt.
Type
String
Default
ENCRYPT_AND_SIGN
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.access-token.include-claims-in-jwtWhether CAS should include extra CAS attributes as claims in the JWT access token.
true

Whether CAS should include extra CAS attributes as claims in the JWT access token. This setting is only relevant if the access token is a determined to be a JWT.

Type
Boolean
Default
true
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.access-token.max-active-tokens-allowedMaximum number of active access tokens that an application can receive.
0

Maximum number of active access tokens that an application can receive. If the application requests more that this limit, the request will be denied and the access token will not be issued.

Type
Long
Default
0
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.access-token.max-time-to-live-in-secondsHard timeout to kill the access token and expire it.
PT8H
Duration

Hard timeout to kill the access token and expire it.

Type
String
Default
PT8H
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.access-token.storage-nameThe storage object name used and created by CAS to hold OAuth access tokens in the backing ticket registry implementation.
oauthAccessTokensCache

The storage object name used and created by CAS to hold OAuth access tokens in the backing ticket registry implementation.

Type
String
Default
oauthAccessTokensCache
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.access-token.time-to-kill-in-secondsSliding window for the access token expiration policy.
PT2H
Duration

Sliding window for the access token expiration policy. Essentially, this is an idle time out.

Type
String
Default
PT2H
Defined by
OAuthAccessTokenProperties
cas.authn.oauth.code.number-of-usesNumber of times this code is valid and can be used.
1

Number of times this code is valid and can be used.

Type
Integer
Default
1
Defined by
OAuthCodeProperties
cas.authn.oauth.code.remove-related-access-tokensRemove the related access tokens when trying to use a code which is expired or no longer exists.
false

Remove the related access tokens when trying to use a code which is expired or no longer exists.

Type
Boolean
Default
false
Defined by
OAuthCodeProperties
cas.authn.oauth.code.storage-nameThe storage object name used and created by CAS to hold OAuth codes in the backing ticket registry implementation.
oauthCodesCache

The storage object name used and created by CAS to hold OAuth codes in the backing ticket registry implementation.

Type
String
Default
oauthCodesCache
Defined by
OAuthCodeProperties
cas.authn.oauth.code.time-to-kill-in-secondsDuration in seconds where the code is valid.
30

Duration in seconds where the code is valid.

Type
Long
Default
30
Defined by
OAuthCodeProperties
cas.authn.oauth.core.bypass-approval-promptWhether approval prompt/consent screen should be bypassed.
false

Whether approval prompt/consent screen should be bypassed.

Type
Boolean
Default
false
Defined by
OAuthCoreProperties
cas.authn.oauth.core.user-profile-view-typeUser profile view type determines how the final user profile should be rendered once an access token is "validated".
NESTED
User profile view type determines how the final user profile should be rendered once an access token is "validated". Available values are as follows:
  • NESTED: Return and render the user profile view in nested mode. This is the default option, most usually.
  • FLAT: Return and render the user profile view in flattened mode where all attributes are flattened down to one level only.
Type
OAuthCoreProperties.UserProfileViewTypes
Default
NESTED
Defined by
OAuthCoreProperties
cas.authn.oauth.crypto.algThe signing/encryption algorithm to use.
no default

The signing/encryption algorithm to use.

Type
String
Default
none
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.crypto.enabledWhether crypto operations are enabled.
true

Whether crypto operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.crypto.encryption-enabledWhether crypto encryption operations are enabled.
true

Whether crypto encryption operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.crypto.encryption.key-sizeThe encryption key size.
512

The encryption key size.

Type
Integer
Default
512
Defined by
EncryptionJwtCryptoProperties
cas.authn.oauth.crypto.signing-enabledWhether crypto signing operations are enabled.
true

Whether crypto signing operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.crypto.signing.key-sizeThe signing key size.
512

The signing key size.

Type
Integer
Default
512
Defined by
SigningJwtCryptoProperties
cas.authn.oauth.crypto.strategy-typeControl the cipher sequence of operations.
ENCRYPT_AND_SIGN
Control the cipher sequence of operations. The accepted values are:
  • ENCRYPT_AND_SIGN: Encrypt the value first, and then sign.
  • SIGN_AND_ENCRYPT: Sign the value first, and then encrypt.
Type
String
Default
ENCRYPT_AND_SIGN
Defined by
EncryptionOptionalSigningOptionalJwtCryptographyProperties
cas.authn.oauth.csrf-cookie.domainCookie domain.
no default

Cookie domain. Specifies the domain within which this cookie should be presented. The form of the domain name is specified by RFC 2965. A domain name begins with a dot (.foo.com) and means that the cookie is visible to servers in a specified Domain Name System (DNS) zone (for example, www.foo.com, but not a.b.foo.com). By default, cookies are only returned to the server that sent them.

Type
String
Default
none
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.http-onlytrue if this cookie contains the HttpOnly attribute.
true

true if this cookie contains the HttpOnly attribute. This means that the cookie should not be accessible to scripting engines, like javascript.

Type
Boolean
Default
true
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.max-ageThe maximum age of the cookie, specified in seconds.
-1
Duration

The maximum age of the cookie, specified in seconds. By default, -1 indicating the cookie will persist until browser shutdown. A positive value indicates that the cookie will expire after that many seconds have passed. Note that the value is the maximum age when the cookie will expire, not the cookie's current age. A negative value means that the cookie is not stored persistently and will be deleted when the Web browser exits. A zero value causes the cookie to be deleted.

Type
String
Default
-1
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.nameCookie name.
no default

Cookie name. Constructs a cookie with a specified name and value. The name must conform to RFC 2965. That means it can contain only ASCII alphanumeric characters and cannot contain commas, semicolons, or white space or begin with a $ character. The cookie's name cannot be changed after creation. By default, cookies are created according to the RFC 2965 cookie specification. Cookie names are automatically calculated assigned by CAS at runtime, and there is usually no need to customize the name or assign it a different value unless a special use case warrants the change.

Type
String
Default
none
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.pathCookie path.
no default

Cookie path. Specifies a path for the cookie to which the client should return the cookie. The cookie is visible to all the pages in the directory you specify, and all the pages in that directory's subdirectories. A cookie's path must include the servlet that set the cookie, for example, /catalog, which makes the cookie visible to all directories on the server under /catalog. Consult RFC 2965 (available on the Internet) for more information on setting path names for cookies.

Type
String
Default
none
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.same-site-policyIf a cookie is only intended to be accessed in a first party context, the developer has the option to apply one of settings SameSite=Lax or SameSite=Strict or SameSite=None to prevent external access.
no default

If a cookie is only intended to be accessed in a first party context, the developer has the option to apply one of settings SameSite=Lax or SameSite=Strict or SameSite=None to prevent external access.

To safeguard more websites and their users, the new secure-by-default model assumes all cookies should be protected from external access unless otherwise specified. Developers must use a new cookie setting, SameSite=None, to designate cookies for cross-site access. When the SameSite=None attribute is present, an additional Secure attribute is used so cross-site cookies can only be accessed over HTTPS connections.

Accepted values are:
  • Lax
  • Strict
  • None
  • Off: Disable the generation of the SameSite cookie attribute altogether.
  • Path to a Groovy script that is able to generate the SameSite cookie attribute dynamically.
  • Fully qualified name of a class that implements org.apereo.cas.web.cookie.CookieSameSitePolicy
Type
String
Default
none
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.csrf-cookie.secureTrue if sending this cookie should be restricted to a secure protocol, or false if the it can be sent using any protocol.
true

True if sending this cookie should be restricted to a secure protocol, or false if the it can be sent using any protocol.

Type
Boolean
Default
true
Defined by
OAuthCsrfCookieProperties
cas.authn.oauth.device-token.max-time-to-live-in-secondsHard timeout to kill the device token and expire it.
PT5M
Duration

Hard timeout to kill the device token and expire it.

Type
String
Default
PT5M
Defined by
OAuthDeviceTokenProperties
cas.authn.oauth.device-token.refresh-intervalThe device refresh interval.
PT15S
Duration

The device refresh interval. The client should attempt to acquire an access token every few seconds (at a rate specified by interval) by POSTing to the access token endpoint on the server.

Type
String
Default
PT15S
Defined by
OAuthDeviceTokenProperties
cas.authn.oauth.device-token.storage-nameThe storage object name used and created by CAS to hold OAuth device tokens in the backing ticket registry implementation.
oauthDeviceTokensCache

The storage object name used and created by CAS to hold OAuth device tokens in the backing ticket registry implementation.

Type
String
Default
oauthDeviceTokensCache
Defined by
OAuthDeviceTokenProperties
cas.authn.oauth.device-user-code.max-time-to-live-in-secondsHard timeout to kill the token and expire it.
PT1M
Duration

Hard timeout to kill the token and expire it.

Type
String
Default
PT1M
Defined by
OAuthDeviceUserCodeProperties
cas.authn.oauth.device-user-code.storage-nameThe storage object name used and created by CAS to hold OAuth device user codes in the backing ticket registry implementation.
oauthDeviceUserCodesCache

The storage object name used and created by CAS to hold OAuth device user codes in the backing ticket registry implementation.

Type
String
Default
oauthDeviceUserCodesCache
Defined by
OAuthDeviceUserCodeProperties
cas.authn.oauth.device-user-code.user-code-lengthLength of the generated user code.
8

Length of the generated user code.

Type
Integer
Default
8
Defined by
OAuthDeviceUserCodeProperties
cas.authn.oauth.grants.resource-owner.require-service-headerWhether using the resource-owner grant should enforce authorization rules and per-service policies based on a service parameter is provided as a header outside the normal semantics of the grant and protocol.
false

Whether using the resource-owner grant should enforce authorization rules and per-service policies based on a service parameter is provided as a header outside the normal semantics of the grant and protocol.

Type
Boolean
Default
false
Defined by
ResourceOwner
cas.authn.oauth.refresh-token.create-as-jwtCreate access token as JWTs.
false

Create access token as JWTs.

Type
Boolean
Default
false
Defined by
OAuthRefreshTokenProperties
cas.authn.oauth.refresh-token.max-active-tokens-allowedMaximum number of active refresh tokens that an application can receive.
0

Maximum number of active refresh tokens that an application can receive. If the application requests more that this limit, the request will be denied and the access token will not be issued.

Type
Long
Default
0
Defined by
OAuthRefreshTokenProperties
cas.authn.oauth.refresh-token.storage-nameThe storage object name used and created by CAS to hold OAuth refresh tokens in the backing ticket registry implementation.
oauthRefreshTokensCache

The storage object name used and created by CAS to hold OAuth refresh tokens in the backing ticket registry implementation.

Type
String
Default
oauthRefreshTokensCache
Defined by
OAuthRefreshTokenProperties
cas.authn.oauth.refresh-token.time-to-kill-in-secondsHard timeout beyond which the refresh token is considered expired.
P14D
Duration

Hard timeout beyond which the refresh token is considered expired.

Type
String
Default
P14D
Defined by
OAuthRefreshTokenProperties
cas.authn.oauth.refresh-token.track-access-tokensIf true, the refresh token will keep track of the access tokens issued using it.
true

If true, the refresh token will keep track of the access tokens issued using it. The access tokens will remain attached to the refresh token as long as the refresh token is valid and they are not periodically on on-demand checked for validity or removed from the refresh token if they expire. The tracking mechanism is only for history and auditing purposes.

Type
Boolean
Default
true
Defined by
OAuthRefreshTokenProperties
cas.authn.oauth.session-replication.cookie.allowed-ip-addresses-patternA regular expression pattern that indicates the set of allowed IP addresses, when #isPinToSession() is configured.
no default
Regex

A regular expression pattern that indicates the set of allowed IP addresses, when #isPinToSession() is configured. In the event that there is a mismatch between the cookie IP address and the current request-provided IP address (i.e. network switches, VPN, etc), the cookie can still be considered valid if the new IP address matches the pattern specified here.

Type
String
Default
none
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.auto-configure-cookie-pathDecide if cookie paths should be automatically configured based on the application context path, when the cookie path is not configured.
true

Decide if cookie paths should be automatically configured based on the application context path, when the cookie path is not configured. @deprecated since 7.3.0

Type
Boolean
Default
true
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.crypto.algThe signing/encryption algorithm to use.
no default

The signing/encryption algorithm to use.

Type
String
Default
none
Defined by
EncryptionJwtSigningJwtCryptographyProperties
cas.authn.oauth.session-replication.cookie.crypto.enabledWhether crypto operations are enabled.
true

Whether crypto operations are enabled.

Type
Boolean
Default
true
Defined by
EncryptionJwtSigningJwtCryptographyProperties
cas.authn.oauth.session-replication.cookie.crypto.encryption.key-sizeThe encryption key size.
512

The encryption key size.

Type
Integer
Default
512
Defined by
EncryptionJwtCryptoProperties
cas.authn.oauth.session-replication.cookie.crypto.signing.key-sizeThe signing key size.
512

The signing key size.

Type
Integer
Default
512
Defined by
SigningJwtCryptoProperties
cas.authn.oauth.session-replication.cookie.crypto.strategy-typeControl the cipher sequence of operations.
ENCRYPT_AND_SIGN
Control the cipher sequence of operations. The accepted values are:
  • ENCRYPT_AND_SIGN: Encrypt the value first, and then sign.
  • SIGN_AND_ENCRYPT: Sign the value first, and then encrypt.
Type
String
Default
ENCRYPT_AND_SIGN
Defined by
EncryptionJwtSigningJwtCryptographyProperties
cas.authn.oauth.session-replication.cookie.domainCookie domain.
no default

Cookie domain. Specifies the domain within which this cookie should be presented. The form of the domain name is specified by RFC 2965. A domain name begins with a dot (.foo.com) and means that the cookie is visible to servers in a specified Domain Name System (DNS) zone (for example, www.foo.com, but not a.b.foo.com). By default, cookies are only returned to the server that sent them.

Type
String
Default
none
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.geo-locate-client-sessionWhen set to true and assuming #isPinToSession() is also true , client sessions (using the client IP address) are geo-located using a geolocation service when/if configured.
false

When set to true and assuming #isPinToSession() is also true, client sessions (using the client IP address) are geo-located using a geolocation service when/if configured. The resulting session is either pinned to the client geolocation, or the default client address.

Type
Boolean
Default
false
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.http-onlytrue if this cookie contains the HttpOnly attribute.
true

true if this cookie contains the HttpOnly attribute. This means that the cookie should not be accessible to scripting engines, like javascript.

Type
Boolean
Default
true
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.max-ageThe maximum age of the cookie, specified in seconds.
-1
Duration

The maximum age of the cookie, specified in seconds. By default, -1 indicating the cookie will persist until browser shutdown. A positive value indicates that the cookie will expire after that many seconds have passed. Note that the value is the maximum age when the cookie will expire, not the cookie's current age. A negative value means that the cookie is not stored persistently and will be deleted when the Web browser exits. A zero value causes the cookie to be deleted.

Type
String
Default
-1
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.nameCookie name.
no default

Cookie name. Constructs a cookie with a specified name and value. The name must conform to RFC 2965. That means it can contain only ASCII alphanumeric characters and cannot contain commas, semicolons, or white space or begin with a $ character. The cookie's name cannot be changed after creation. By default, cookies are created according to the RFC 2965 cookie specification. Cookie names are automatically calculated assigned by CAS at runtime, and there is usually no need to customize the name or assign it a different value unless a special use case warrants the change.

Type
String
Default
none
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.pathCookie path.
no default

Cookie path. Specifies a path for the cookie to which the client should return the cookie. The cookie is visible to all the pages in the directory you specify, and all the pages in that directory's subdirectories. A cookie's path must include the servlet that set the cookie, for example, /catalog, which makes the cookie visible to all directories on the server under /catalog. Consult RFC 2965 (available on the Internet) for more information on setting path names for cookies.

Type
String
Default
none
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.pin-to-sessionWhen generating cookie values, determine whether the value should be compounded and signed with the properties of the current session, such as IP address, user-agent, etc.
true

When generating cookie values, determine whether the value should be compounded and signed with the properties of the current session, such as IP address, user-agent, etc.

Turning off session pinning is not exactly ideal. This is a barrier to prevent cookie replay attacks. A cookie that was created with an IP given a certain location cannot be replayed back in a different browser with a different IP from a different location.

There may however be legitimate reasons to turn it off and relax this after careful reviews, if you intend to support a type of user who intends to switch their IP quite frequently. A classic example is the type of user that is on VPN at the time of login, but decides to resume their work a few hours later off VPN or at a different location.

Type
Boolean
Default
true
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.same-site-policyIf a cookie is only intended to be accessed in a first party context, the developer has the option to apply one of settings SameSite=Lax or SameSite=Strict or SameSite=None to prevent external access.
no default

If a cookie is only intended to be accessed in a first party context, the developer has the option to apply one of settings SameSite=Lax or SameSite=Strict or SameSite=None to prevent external access.

To safeguard more websites and their users, the new secure-by-default model assumes all cookies should be protected from external access unless otherwise specified. Developers must use a new cookie setting, SameSite=None, to designate cookies for cross-site access. When the SameSite=None attribute is present, an additional Secure attribute is used so cross-site cookies can only be accessed over HTTPS connections.

Accepted values are:
  • Lax
  • Strict
  • None
  • Off: Disable the generation of the SameSite cookie attribute altogether.
  • Path to a Groovy script that is able to generate the SameSite cookie attribute dynamically.
  • Fully qualified name of a class that implements org.apereo.cas.web.cookie.CookieSameSitePolicy
Type
String
Default
none
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.cookie.secureTrue if sending this cookie should be restricted to a secure protocol, or false if the it can be sent using any protocol.
true

True if sending this cookie should be restricted to a secure protocol, or false if the it can be sent using any protocol.

Type
Boolean
Default
true
Defined by
CookieSessionReplicationProperties
cas.authn.oauth.session-replication.replicate-sessionsIndicates whether profiles and other session data, collected as part of authentication flows and protocol requests that are kept by the container session, should be replicated across the cluster using CAS and its own...
false

Indicates whether profiles and other session data, collected as part of authentication flows and protocol requests that are kept by the container session, should be replicated across the cluster using CAS and its own ticket registry. Without this option, profile data and other related pieces of information should be manually replicated via means and libraries outside of CAS. @deprecated since 7.3.0

Type
Boolean
Default
false
Defined by
SessionReplicationProperties

Required settings may be needed to activate or affect the feature; review them even when they have a default. Optional settings only need to be set to change a default or to turn on the behavior they control. Third party settings belong to libraries such as Spring Boot that CAS builds on; their own documentation may have more detail.

Signing & encryption

This CAS feature is able to accept signing and encryption crypto keys. In most scenarios if keys are not provided, CAS will auto-generate them. The following instructions apply if you wish to manually and beforehand create the signing and encryption keys.

Note that if you are asked to create a JWK of a certain size for the key, you are to use the following set of commands to generate the token:

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wget https://raw.githubusercontent.com/apereo/cas/master/etc/jwk-gen.jar
java -jar jwk-gen.jar -t oct -s [size]

The outcome would be similar to:

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{
  "kty": "oct",
  "kid": "...",
  "k": "..."
}

The generated value for k needs to be assigned to the relevant CAS settings. Note that keys generated via the above algorithm are processed by CAS using the Advanced Encryption Standard (AES) algorithm which is a specification for the encryption of electronic data established by the U.S. National Institute of Standards and Technology.


Notes on configuration

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, especially 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.

Endpoints

After enabling OAuth support, the following endpoints will be available:

Endpoint Description Method
/oauth2.0/authorize Authorize the user and start the CAS authentication flow. GET
/oauth2.0/accessToken,/oauth2.0/token Get an access token in plain-text or JSON POST
/oauth2.0/profile Get the authenticated user profile in JSON via access_token parameter. GET
/oauth2.0/introspect Query CAS to detect the status of a given access token via introspection POST
/oauth2.0/device Approve device user codes via the device flow protocol. POST
/oauth2.0/revoke Revoke access or refresh tokens. This endpoint expects HTTP basic authentication with OAuth2 service client_id and client_secret associated as username and password. POST

Protocol Flows

The following protocol flows, response and grant types are supported.

Flow Resource
Authorization Code / PKCE See this page.
Client Credentials See this page.
Device Authorization See this page.
Token Exchange See this page.
Token / Implicit See this page.
Refresh Token See this page.
Resource Owner See this page.

Throttling

Authentication throttling may be enabled for the /oauth2.0/accessToken provided support is included in the overlay to turn on authentication throttling support. The throttling mechanism that handles the usual CAS server endpoints for authentication and ticket validation, etc is then activated for the OAuth endpoints that are supported for throttling.

Sample Client Applications

Troubleshooting

To enable additional logging, configure the log4j configuration file to add the following levels:

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...
<Logger name="org.apereo.cas.oauth" level="debug" additivity="false">
    <AppenderRef ref="casConsole"/>
    <AppenderRef ref="casFile"/>
</Logger>
<Logger name="PROTOCOL_MESSAGE" level="debug" additivity="false">
    <AppenderRef ref="casConsole"/>
    <AppenderRef ref="casFile"/>
</Logger>
...