Microsoft Entra ID Authentication
Microsoft Entra ID is Microsoft’s cloud-based identity and access management service. The functionality described here allows one to authenticate credentials using Microsoft Entra ID as the account store and optionally fetch user attributes using Microsoft Graph.
Configuration
Support is enabled by including the following dependency in the WAR overlay:
1
2
3
4
5
<dependency>
<groupId>org.apereo.cas</groupId>
<artifactId>cas-server-support-azuread-authentication</artifactId>
<version>${cas.version}</version>
</dependency>
1
implementation "org.apereo.cas:cas-server-support-azuread-authentication:${project.'cas.version'}"
1
2
3
4
5
6
7
8
9
dependencyManagement {
imports {
mavenBom "org.apereo.cas:cas-server-support-bom:${project.'cas.version'}"
}
}
dependencies {
implementation "org.apereo.cas:cas-server-support-azuread-authentication"
}
1
2
3
4
5
6
7
8
9
10
dependencies {
/*
The following platform references are included automatically and are listed for reference only.
implementation enforcedPlatform("org.apereo.cas:cas-server-support-bom:${project.'cas.version'}")
implementation platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES)
*/
implementation "org.apereo.cas:cas-server-support-azuread-authentication"
}
The following settings and properties are available from the CAS configuration catalog:
cas.authn.azure-active-directory.client-idClient id of the application.
Client id of the application.
cas.authn.azure-active-directory.client-secretClient secret of the registered app in microsoft azure portal.
Client secret of the registered app in microsoft azure portal.
cas.authn.azure-active-directory.password-encoder.encoding-algorithmThe encoding algorithm to use such as MD5 .
The encoding algorithm to use such as MD5. Relevant when the type used is DEFAULT or GLIBC_CRYPT. When used with PasswordEncoderTypes#PBKDF2, it should be one of PBKDF2WithHmacSHA1, PBKDF2WithHmacSHA256 or PBKDF2WithHmacSHA512.
cas.authn.azure-active-directory.password-encoder.typeDefine the password encoder type to use.
NONEDefine the password encoder type to use. Type may be specified as blank or NONE to disable password encoding. It may also refer to a fully-qualified class name that implements the Spring Security's PasswordEncoder interface if you wish you define your own encoder.
-
NONE: No password encoding (i.e. plain-text) takes place. -
DEFAULT: Use theDefaultPasswordEncoderof CAS. For message-digest algorithms viacharacter-encodingandencoding-algorithm. -
BCRYPT: Use theBCryptPasswordEncoderbased on the strength provided and an optional secret. -
SCRYPT: Use theSCryptPasswordEncoder. -
PBKDF2: Use thePbkdf2PasswordEncoderbased on the strength provided and an optional secret. -
STANDARD: Use theStandardPasswordEncoderbased on the secret provided. -
SSHA: Use theLdapShaPasswordEncodersupports Ldap SHA and SSHA (salted-SHA). The values are base-64 encoded and have the label {SHA} or {SSHA} prepended to the encoded hash. -
GLIBC_CRYPT: Use theGlibcCryptPasswordEncoderbased on theencoding-algorithm, strength provided and an optional secret. -
org.example.MyEncoder: An implementation ofPasswordEncoderof your own choosing. -
file:///path/to/script.groovy: Path to a Groovy script charged with handling password encoding operations.
cas.authn.azure-active-directory.principal-transformation.groovy.locationThe location of the resource.
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, especially if the script is set to reload on changes, you may need to adjust the total number of inotify 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.
In situations and scenarios where CAS is able to automatically watch the underlying resource for changes and detect updates and modifications dynamically, you may be able to specify the following setting as either an environment variable or system property with a value of false to disable the resource watcher: org.apereo.cas.util.io.PathWatcherService.
cas.authn.azure-active-directory.tenantThe microsoft tenant id.
The microsoft tenant id.
cas.authn.azure-active-directory.credential-criteriaA number of authentication handlers are allowed to determine whether they can operate on the provided credential and as such lend themselves to be tried and tested during the authentication handler selection phase.
- 1) A regular expression pattern that is tested against the credential identifier.
- 2) A fully qualified class name of your own design that implements
Predicate. - 3) Path to an external Groovy script that implements the same interface.
cas.authn.azure-active-directory.enabledEnable authentication against Azure active directory.
trueEnable authentication against Azure active directory.
cas.authn.azure-active-directory.login-urlThis URL of the security token service that CAS goes to for acquiring tokens for resources and users This URL allows CAS to establish what is called an 'authority'.
https://login.microsoftonline.com/common/https://<instance>/<tenant>, where 'instance' is the Azure AD host (such as https://login.microsoftonline.com) and 'tenant' is the domain name (such as contoso.onmicrosoft.com) or tenant ID of the directory. Examples of authority URL are: -
https://login.microsoftonline.com/f31e6716-26e8-4651-b323-2563936b4163: for a single tenant application defined in the tenant -
https://login.microsoftonline.com/contoso.onmicrosoft.com: This representation is like the previous one, but uses the tenant domain name instead of the tenant Id. -
https://login.microsoftonline.de/contoso.de: also uses a domain name, but in this case the Azure AD tenant admins have set a custom domain for their tenant, and the instance URL here is for the German national cloud. -
https://login.microsoftonline.com/common: in the case of a multi-tenant application, that is an application available in several Azure AD tenants. - It can finally be an Active Directory Federation Services (ADFS) URL, which is recognized with the convention that the URL should contain adfs like
https://contoso.com/adfs.
cas.authn.azure-active-directory.nameThe name of the authentication handler.
The name of the authentication handler.
cas.authn.azure-active-directory.orderThe order of this authentication handler in the chain.
The order of this authentication handler in the chain.
cas.authn.azure-active-directory.password-encoder.character-encodingThe encoding algorithm to use such as 'UTF-8'.
UTF-8The encoding algorithm to use such as 'UTF-8'. Relevant when the type used is DEFAULT.
cas.authn.azure-active-directory.password-encoder.hash-lengthWhen used by PasswordEncoderTypes#ARGON2 , it indicates the hash strength/length.
16When used by PasswordEncoderTypes#ARGON2, it indicates the hash strength/length.
cas.authn.azure-active-directory.password-encoder.iterationsWhen used by PasswordEncoderTypes#PBKDF2 , it indicates the required number of iterations.
310000When used by PasswordEncoderTypes#PBKDF2, it indicates the required number of iterations.
cas.authn.azure-active-directory.password-encoder.secretSecret to use with PasswordEncoderTypes#STANDARD , PasswordEncoderTypes#PBKDF2 , PasswordEncoderTypes#BCRYPT , PasswordEncoderTypes#GLIBC_CRYPT password encoders.
Secret to use with PasswordEncoderTypes#STANDARD, PasswordEncoderTypes#PBKDF2, PasswordEncoderTypes#BCRYPT, PasswordEncoderTypes#GLIBC_CRYPT password encoders. Secret usually is an optional setting.
cas.authn.azure-active-directory.password-encoder.strengthStrength or number of iterations to use for password hashing.
16Strength or number of iterations to use for password hashing. Usually relevant when dealing with PasswordEncoderTypes#BCRYPT, PasswordEncoderTypes#PBKDF2 or PasswordEncoderTypes#GLIBC_CRYPT. When used by PasswordEncoderTypes#ARGON2 or PasswordEncoderTypes#PBKDF2, it indicates the salt strength.
cas.authn.azure-active-directory.principal-transformation.blocking-patternA regular expression that will be used against the username to match for blocking/forbidden values.
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.
cas.authn.azure-active-directory.principal-transformation.case-conversionIndicate whether the principal identifier should be transformed into upper-case, lower-case, etc.
NONE-
NONE: No conversion. -
LOWERCASE: Lowercase conversion. -
UPPERCASE: Uppercase conversion.
cas.authn.azure-active-directory.principal-transformation.patternA regular expression that will be used against the provided username for username extractions.
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.
cas.authn.azure-active-directory.principal-transformation.prefixPrefix to add to the principal id prior to authentication.
Prefix to add to the principal id prior to authentication.
cas.authn.azure-active-directory.principal-transformation.suffixSuffix to add to the principal id prior to authentication.
Suffix to add to the principal id prior to authentication.
cas.authn.azure-active-directory.resourceResource url for the graph API to fetch attributes.
https://graph.microsoft.com/Resource url for the graph API to fetch attributes.
cas.authn.azure-active-directory.scopeScope used when fetching access tokens.
openid,email,profile,addressScope used when fetching access tokens. Multiple scopes may be separated using a comma.
cas.authn.azure-active-directory.stateDefine the scope and state of this authentication handler and the lifecycle in which it can be invoked or activated.
active-
ACTIVE: Active authentication handler, and is invoked by default automatically to verify credentials globally. -
STANDBY: Authentication handler is in a semi-enabled state, waiting to be called only on-demand when explicitly asked for.
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.
Groovy scripting
CAS takes advantage of Apache Groovy in forms of either embedded or external scripts that allow one to, by default, dynamically build constructs, attributes, access strategies and a lot more. To activate the functionality described here, you may need to prepare CAS to support and integrate with Apache Groovy.
Please review this guide to configure your build.
Authentication
Certain authentication handlers are allowed to determine whether they can operate on the provided credential and as such lend themselves to be tried and tested during the authentication handler selection phase. The credential criteria may be one of the following options:
- A regular expression pattern that is tested against the credential identifier.
- A fully qualified class name of your own design that looks similar to the below example:
1
2
3
4
5
6
7
8
9
import java.util.function.Predicate;
import org.apereo.cas.authentication.Credential;
public class PredicateExample implements Predicate<Credential> {
@Override
public boolean test(final Credential credential) {
// Examine the credential and return true/false
}
}
- Path to an external Groovy script that looks similar to the below example:
1
2
3
4
5
6
7
8
9
import org.apereo.cas.authentication.Credential
import java.util.function.Predicate
class PredicateExample implements Predicate<Credential> {
@Override
boolean test(final Credential credential) {
// test and return result
}
}
To prepare CAS to support and integrate with Apache Groovy, please review this guide.
Password encoding
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:
1
2
3
4
5
6
7
8
9
10
11
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:
1
2
3
4
5
6
7
8
9
10
11
12
import java.util.*
byte[] run(final Object... args) {
def (rawPassword,generatedSalt,logger,applicationContext) = args
logger.debug("Encoding password...")
return ...
}
Boolean matches(final Object... args) {
def (rawPassword,encodedPassword,logger,applicationContext) = args
logger.debug("Does match or not ?");
return ...
To prepare CAS to support and integrate with Apache Groovy, please review this guide.
Principal transformation
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:
1
2
3
4
String run(final Object... args) {
def (providedUsername,logger) = args
return providedUsername.concat("SomethingElse")
}
To prepare CAS to support and integrate with Apache Groovy, please review this guide.
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.
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.
Principal Attributes
The above dependency may also be used, in the event that principal attributes need to be fetched from Microsoft Entra ID without necessarily authenticating credentials .
The following settings and properties are available from the CAS configuration catalog:
cas.authn.attribute-repository.azure-active-directory[0].client-idClient id of the registered app in microsoft azure portal.
Client id of the registered app in microsoft azure portal.
cas.authn.attribute-repository.azure-active-directory[0].client-secretClient secret of the registered app in microsoft azure portal.
Client secret of the registered app in microsoft azure portal.
cas.authn.attribute-repository.azure-active-directoryRetrieve attributes from multiple Microsoft Graph instances.
Retrieve attributes from multiple Microsoft Graph instances.
cas.authn.attribute-repository.azure-active-directory[0].api-base-urlBase API url used to contact microsoft graph for calls.
Base API url used to contact microsoft graph for calls.
cas.authn.attribute-repository.azure-active-directory[0].attributesComma-separated attributes and user properties to fetch from microsoft graph.
Comma-separated attributes and user properties to fetch from microsoft graph. If attributes are specified here, they would be the only ones requested and fetched. If this field is left blank, a default set of attributes are fetched and returned.
cas.authn.attribute-repository.azure-active-directory[0].case-insensitiveWhether attribute repository should consider the underlying attribute names in a case-insensitive manner.
Whether attribute repository should consider the underlying attribute names in a case-insensitive manner.
cas.authn.attribute-repository.azure-active-directory[0].domainDomain that is appended to usernames when doing lookups.
Domain that is appended to usernames when doing lookups. The @ is automatically included.
cas.authn.attribute-repository.azure-active-directory[0].grant-typeGrant type used to fetch access tokens; defaults to client_credentials .
Grant type used to fetch access tokens; defaults to client_credentials.
cas.authn.attribute-repository.azure-active-directory[0].idA value can be assigned to this field to uniquely identify this resolver.
A value can be assigned to this field to uniquely identify this resolver.
cas.authn.attribute-repository.azure-active-directory[0].logging-levelAdjust the logging level of the API calls.
Adjust the logging level of the API calls. Defaults to basic. Accepted values are none,headers,basic,body.
cas.authn.attribute-repository.azure-active-directory[0].login-base-urlBase login url used to fetch access tokens.
Base login url used to fetch access tokens.
cas.authn.attribute-repository.azure-active-directory[0].orderThe order of this attribute repository in the chain of repositories.
The order of this attribute repository in the chain of repositories. Can be used to explicitly position this source in chain and affects merging strategies.
cas.authn.attribute-repository.azure-active-directory[0].resourceResource to fetch access tokens for; defaults to the graph api url.
Resource to fetch access tokens for; defaults to the graph api url.
cas.authn.attribute-repository.azure-active-directory[0].scopeScope used when fetching access tokens.
Scope used when fetching access tokens.
cas.authn.attribute-repository.azure-active-directory[0].tenantThe microsoft tenant id.
The microsoft tenant id.
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.
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.
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.