OpenID Connect Client
1.0

This feature enables web applications to integrate OpenID Connect Client 1.0 for authenticating users instead of, or in addition to, the configured user registry.

You can configure an Open Liberty server to function as an OpenID Connect client, or Relying Party (RP), so that you can use an OpenID Connect Provider (OP) as a single-sign-on identity provider.

You can use the OpenIdAuthenticationMechanismDefinition annotation in a web or RESTful Web Services (JAX-RS) application to enable an OpenID Connect client for that application. This annotation is supported when you enable the Application Security feature version 5.0 or later. You do not need to enable the OpenID Connect Client feature to use this annotation. For more information, For more information, see Enable an OpenID Connect client for an application.

Enabling this feature

To enable the OpenID Connect Client 1.0 feature, add the following element declaration into your server.xml file, inside the featureManager element:

<feature>openidConnectClient-1.0</feature>

Examples

The following examples demonstrate configuration options for the OpenID Connect Client feature, which is specified on the openidConnectClient element in your server.xml file. For a full list of configuration attributes, see the openidConnectClient element.

Minimal configuration for Open Liberty to act as an OpenID Connect client

To enable your Open Liberty server to act as an OpenID Connect (OIDC) client, you must configure the following prerequisites.

  • Enable the OpenID Connect Client and Transport Security features.

  • Configure a user registry.

    User identities that are returned by an OIDC Provider (OP) are not mapped to a registry user by default, so no users are required to be configured in the registry. However, if the mapIdentityToRegistryUser attribute of the openidConnectClient element is set to true, a user entry must exist for the identity that is returned from the OP.

  • Configure a truststore for the server that includes the signer certificates of the OIDC Providers that are supported. Truststores are configured on the keyStore element in the server.xml file.

    OIDC uses the default TLS configuration that is specified by the server. Therefore, unless you specify an alternative TLS configuration for OIDC, the default TLS configuration for the server must reference the truststore that is configured for OIDC. The following example shows a default TLS configuration in the server.xml file that is modified to include a truststore that contains signer certificates for OIDC.

    <sslDefault sslRef="DefaultSSLSettings" />
<ssl id="DefaultSSLSettings" keyStoreRef="myKeyStore" trustStoreRef="OIDCTrustStore" />
<keyStore id="myKeyStore" password="{xor}EzY9Oi0rJg==" type="PKCS12" location="${server.config.dir}/resources/security/BasicKeyStore.p12" />
<keyStore id="OIDCTrustStore" password="{xor}EzY9Oi0rJg==" type="PKCS12" location="${server.config.dir}/resources/security/OIDCTrustStore.p12" />

    If a default outbound TLS configuration is specified, this configuration must also use the truststore that is configured for OIDC. You can specify a TLS configuration for OIDC other than the default by referencing it from the sslRef attribute of the openidConnectClient element. Alternatively, you can specify a nondefault truststore for OIDC by referencing the truststore configuration from the trustStoreRef attribute for the openidConnectClient element. For more information, see Configure TLS and the openidConnectClient element.

The following example shows the minimal configuration for the openidConnectClient element to work with the default OP. The client must have a configured application that is available at the specified URL pattern that can handle redirect requests from an OP. This URL must also precisely match the redirect URL that is registered for the client with the OP.

<openidConnectClient id="client01"
    clientId="client01"
    clientSecret="{xor}LDo8LTor"
    authorizationEndpointUrl="https://server.example.com:443/oidc/endpoint/OidcConfigSample/authorize"
    tokenEndpointUrl="https://server.example.com:443/oidc/endpoint/OidcConfigSample/token">
</openidConnectClient>

This configuration assumes the following default values.

  • scope=openid profile

    You can use the scope attribute for the openidConnectClient element to edit required scopes. For example, you can change the required scope to openid profile email. For more information about OpenID scopes, see the OpenID Connect specification.

  • The client registers the https://<host name>:<ssl port>/oidcclient/redirect/client01 redirect URL with the OP.

    In this URL, both the hostname and SSL port are automatically resolved and client01 is the value of the id attribute of the openidConnectClient element. If a proxy is in front of the RP, you can override the hostname and port by specifying the redirectToRPHostAndPort attribute, for example, redirectToRPHostAndPort="https://<host name>:<ssl port>".

The OpenID Connect RP cannot route requests through a proxy host automatically. If you use a proxy to access the OP, the values for any OP-related URL properties must contain the proxy host and port, not the external OP host and port. In most cases, you can replace the OP host and port with the proxy host and port. The URL that you enter must be visible to both the RP and the client browser or application that is used to access the application that is hosted by the RP server. For further guidance on how to determine the correct URL to use, contact your proxy administrator.

Configure a discovery endpoint for an OpenID Connect Provider

The following example shows a minimal configuration that automatically discovers the OP.

<openidConnectClient id="RP"
    clientId="ebb996943plm4450bdb674c211a9fab0"
    clientSecret="g12ciZL1zsVYk6yXTMa2iopa8TBwC178CGq42mdJCALYCdQT1kE1ecB010GE"
    discoveryEndpointUrl="https://example.server.com/oidc/endpoint/OidcConfigSample/.well-known/openid-configuration">
</openidConnectClient>

If a discovery endpoint is configured, any other configured OIDC endpoints are ignored and replaced with the following discovered endpoints.

  • issuer

  • authorization_endpoint

  • token_endpoint

  • userinfo_endpoint

  • jwks_uri

  • revocation_endpoint

Configure JSON Web Token (JWT) authentication for OpenID Connect

Any trusted party with a JWT can use that token to get access to the associated resources in Open Liberty. The Open Liberty server validates the JWT and creates the authenticated subject from it. To be accepted as an authentication token, the JWT must contain iss, sub, and exp claims and be signed with a recognized signature algorithm. Recognized signature algorithms are listed as possible values for the signatureAlgorithm attribute of the openidConnectClient element. An unsigned JWT is accepted when the signatureAlgorithm attribute is set to none. JSON Web Encryption (JWE) is also supported.

To configure an Open Liberty server to accept a JWT as an authentication token, you must set the inboundPropagation attribute to required. You must also configure a truststore that includes the JSON Web Key (JWK) endpoint certificate so that the Open Liberty server can make TLS connections to the JWK endpoint. If the default truststore for your server does not include the JWK endpoint certificate, you can reference an alternative truststore from the trustStoreRef attribute for the openidConnectClient element.

In the following example, the default TLS configuration includes the JWK endpoint certificate. This example also assumes that the JWT issuer supports a JWK and the JWT is signed with the RS256 algorithm. The issuerIdentifier attribute is configured to match the JWT issuer iss claim.

<openidConnectClient id="RS" inboundPropagation="required"
  jwkEndpointUrl="https://example.com/jwtserver/jwk" signatureAlgorithm="RS256"
  issuerIdentifier="https://idp.example.com:8020/jwt" >
</openidConnectClient>

The Open Liberty server expects each request to provide a valid JWT token and does not create or use single-sign-on (SSO) cookies for JWT authentication. If you want the Open Liberty server to create SSO cookies, set the authnSessionDisabled attribute on the openidConnectClient element to false.

Open Liberty can use the issuer claim from a JWT or JSON web signature (JWS) access token to select a openidConnectClient configuration in the server.xml file with a matching issuer attribute.

The following server.xml file example shows two Open ID connect client configurations, with an authFilter configured to route requests to the RP2 configuration. If a request with an issuer claim value of https://hostname/op1 is presented, the RP1 configuration is selected unless the rp2filter applies to the request.

<openidConnectClient id="RP1" issuer="https://hostname/op1"  ... />
<openidConnectClient id="RP2" issuer="https://hostname/op2" authFilterRef="rp2filter" .../>

<authFilter id="rp2filter">
  ...
</authFilter>

Open Liberty selects the openidConnectClient configuration to use for a JWT request according to the following algorithm.

  1. If the authentication filter for a openidConnectClient configuration matches the request, choose that configuration.

  2. If the issuer claim from the JWT matches the issuer attribute in only one openidConnectClient configuration element, choose that configuration.

  3. If the issuer claim from the JWT matches the issuer attribute in multiple openidConnectClient configuration elements, choose the first configuration that matches.

  4. If the issuer claim from the JWT does not match the issuer attribute in any openidConnectClient configuration elements, choose between all of the configuration elements in a nondeterministic manner.

    Claim to subject mapping

    If you do not define claim-to-subject mapping, the following default rules apply.

    • The subject (sub) claim is used as the principal name and unique security name of the user.

    • The issuer (iss) claim is the default realm and is used as the subject realm. If a realmName claim is included in the JWT, the realmName claim is used as the subject realm instead of the iss claim.

      You can customize how JWT claims are mapped to the subject that Open Liberty creates by specifying the following openidConnectClient element attributes.

    • userIdentifier

    • userUniqueIdentifier

    • groupIdentifier

    • realmName

    • realmIdentifier

      If both the realmName and realmIdentifier attributes are configured, the realmName value takes precedence and the realmIdentifier value is ignored.

      You can specify an alternative claim as the value for any of these attributes. For example, to use the name claim for the principal name instead of the sub claim, you can specify userIdentifier="name". For more information about these attributes, see the openidConnectClient element.

      You can also programmatically map JWT to subjects by implementing the com.ibm.wsspi.security.oauth.UserCredentialResolver service programming interface (SPI). For information, see the Java documentation that is provided with the Open Liberty installation in the ${wlp.install.dir}/dev/spi/ibm/ directory.

    JWT audiences

    To define a list of trusted audiences, configure the audiences attribute on the openidConnectClient element.

    A valid JWT must satisfy one of the following conditions.

    • If the audiences attribute is configured, the aud claim value in the JWT must be one of the configured audiences. To ignore the audience check, set the audiences attribute to ALL_AUDIENCES.

    • If the audiences attribute is not configured, but the JWT contains an aud claim that is a valid URL, the URL for the resource that is being accessed must include the complete aud value as a prefix.

      For example, the following audience is valid because the resource URL begins with the complete aud claim value from the JWT.

      • Audience claim: "aud":"https://<server>:<port>/something"

      • Resource service URL: https://<server>:<port>/something/specific

    Resource requests

    If a web client sends a JWT to an Open Liberty server in the request Authorization header or as a form-encoded body parameter, no extra server configuration is required. If the JWT is sent in a customized request header field, you must configure the headerName attribute for the openidConnectClient element to equal the name of the field, as shown in the following example.

    <openidConnectClient id="customHeader"
    ...
    headerName="jwt"
    ...
</openidConnectClient>

    With this configuration, a web client can send the token on the jwt header field, as shown in the following resource request example.

    GET /resource HTTP/1.1
Host: server.example.com
jwt: mF_9.B5f-4.1JqM

Accept tokens in JWE format

In version 22.0.0.1 and later, you can configure an Open Liberty OIDC client to process access and ID tokens that are in a JWE format. The corresponding OP must support creating JWE access or ID tokens. Set the OP with the OIDC client public key that is used to encrypt the Content Encryption Key, according to the OIDC Provider documentation.

The following example shows a sample configuration to accept JWTs in JWE format.

<openidConnectClient id="JWE" inboundPropagation="required"
  jwkEndpointUrl="https://example.com/jwtserver/jwk" signatureAlgorithm="RS256"
  issuerIdentifier="https://idp.example.com:8020/jwt"
  keyManagementKeyAlias="privateKeyAlias"
  accessTokenCacheEnabled="true"
  accessTokenCacheTimeout="10s"
  tokenReuse="true">
</openidConnectClient>

  • You must set the keyManagementKeyAlias attribute to the private key alias of the key management key that is used to decrypt the Content Encryption Key of the JWE format token. This key must exist in the keystore that is configured for OIDC.

  • This example specifies optional attributes to configure the RP to cache access token validation results for inbound propagation.

    • The accessTokenCacheEnabled attribute enables validation results to be cached.

    • The accessTokenCacheTimeout attribute specifies a duration that the authenticated subject is cached.

    • The tokenReuse attribute specifies that the OpenID Connect client must cache results for a JWT that includes a jti claim.

If you manage single sign-on (SSO) for OIDC with the Social Login feature, you can enable that feature to process tokens in JWE format. Specify the keyManagementKeyAlias attribute on the oidcLogin element. Set the value to the private key alias of the key management key that is used to decrypt the Content Encryption Key of the JWE format token. For more information, see OIDC Social Login.

Configure a third-party OpenID Connect provider

To configure the Liberty OIDC client to use a third-party OIDC Provider, such as Microsoft Azure or Google, you must configure the following attributes. Obtain these attribute values by calling the OP discovery endpoint, which provides a JSON document at the path that is formed by adding the /.well-known/openid-configuration string to the issuer URI. For example, for Google, this document is available at the https://accounts.google.com/.well-known/openid-configuration URL.

  • jwkEndpointUrl

    Set this attribute to the URL of the OP JSON Web Key Set document that is defined by the jwks_uri value in the discovery file.

  • issuerIdentifier

    Set this attribute to the issuer as defined in the discovery file. An ID Token that does not contain this value as an iss claim is rejected.

  • signatureAlgorithm="RS256"

    The Liberty OIDC client default signature algorithm is HS256.

  • userIdentityToCreateSubject

    Set this attribute to a claim name that is used by the vendor ID Token that represents a user’s unique identifier.

  • groupIdentifier

    Set the attribute to the claim name that represents the user’s group memberships or roles.

The following example shows a sample configuration to connect to Google as an OIDC Provider.

<openidConnectClient id="sample client"
    clientId="ebb996943plm4450bdb674c211a9fab0"
    clientSecret="g12ciZL1zsVYk6yXTMa2iopa8TBwC178CGq42mdJCALYCdQT1kE1ecB010GE"
    discoveryEndpointUrl="https://accounts.google.com/.well-known/openid-configuration"
    jwkEndpointUrl="https://www.googleapis.com/oauth2/v3/certs"
    issuerIdentifier="https://accounts.google.com"
    signatureAlgorithm="RS256"
    userIdentityToCreateSubject="email"
    groupIdentifier="aud">
</openidConnectClient>

Support Multiple OpenID Connect Providers

You can configure Open Liberty as an OIDC client to multiple OPs by creating multiple openidConnectClient elements and setting authentication filters to route incoming authentication requests to each configuration. Each openidConnectClient element defines one SSO relationship with one OIDC Provider. Use the authFilterRef attribute to reference the authentication filter to specify the configured authentication filter for each openidConnectClient element.

In the following example, authentication requests that contain the /mywebapp/members URL pattern are filtered to the OP that is referenced by the RP1 configuration. Authentication requests that contain the /mywebapp/guests URL pattern are filtered to the OP that is referenced by the RP2 configuration.

<openidConnectClient id="RP1"
    authFilterRef="authFilter1"
    clientId="RP1"
    clientSecret="{xor}LDo8LTor"
    authorizationEndpointUrl="https://server.example.com:443/oidc/endpoint/OidcConfigSample/authorize"
    tokenEndpointUrl="https://server.example.com:443/oidc/endpoint/OidcConfigSample/token">
</openidConnectClient>

<openidConnectClient id="RP2"
    authFilterRef="authFilter2"
    clientId="RP2"
    clientSecret="{xor}DLo8LTor"
    authorizationEndpointUrl="https://server.example2.com:443/oidc/endpoint/OidcConfigSample/authorize"
    tokenEndpointUrl="https://server.example2.com:443/oidc/endpoint/OidcConfigSample/token">
</openidConnectClient>

<authFilter id="authFilter1">
    <requestUrl
        id="myUrlFilter"
        urlPattern="/mywebapp/members"
        matchType="contains" />
</authFilter>

<authFilter id="authFilter2">
    <requestUrl
        id="myUrlFilter2"
        urlPattern="/mywebapp/guests"
        matchType="contains" />
</authFilter>

For more information, see Authentication filters.

Use Private Key JWT for client authentication

OpenID Connect clients in Open Liberty support the private_key_jwt client authentication method with OpenID Connect token endpoints. OpenID Connect clients need to provide authentication data to the OpenID Connect provider for accessing the provider’s token endpoint. Clients can authenticate by using several different methods, but most of those methods require a client secret. The private_key_jwt authentication method allows clients to use asymmetric keys to create signed JWTs to authenticate instead of client secrets. By using this authentication method, OpenID Connect clients in Open Liberty no longer need to have a client secret.

Server administrators can enable this function by using the private_key_jwt option for the tokenEndpointAuthMethod attribute, and the new tokenEndpointAuthSigningAlgorithm and keyAliasName attributes in the openidConnectClient element.

<openidConnectClient id="myOidcClientUsingPrivateKeyJwt"
    tokenEndpointAuthMethod="private_key_jwt"
    tokenEndpointAuthSigningAlgorithm="E512"
    keyAliasName="privatekeyaliasES512"
    ...
/>

The tokenEndpointAuthSigningAlgorithm attribute specifies the signing algorithm to sign the JWT that is used for client authentication. The keyAliasName attribute points to the private key to use to sign the JWT. The private key must be present in the keystore that is specified by the sslRef attribute in the OpenID Connect client configuration. OpenID Connect providers that support Private Key JWT client authentication typically provide an interface for administrators to upload their corresponding public key.

For more information on private_key_jwt client authentication, see the OpenID Connect core specification and RFC 7523.

Disable LTPA cookies

The Open Liberty OIDC client automatically creates an SSO token after the ID Token is processed. You can configure the server not to create an SSO token by specifying the disableLtpaCookie attribute for the openidConnectClient element.

<openidConnectClient id="nocookie"
    ...
    disableLtpaCookie="true"
    ...
</openidConnectClient>

When you set this attribute to true, the Open Liberty OIDC client accepts only authentication requests that were previously authenticated with the configured OP. The authentication session lifetime is limited to the lifetime of the ID Token from that OP.

Accept an OAuth 2.0 bearer access token without redirecting to an OpenID Connect provider

You can configure an OIDC client to optionally accept a valid OAuth 2.0 bearer access token as an authentication token without redirecting the request to an OIDC provider. With this configuration, if a request contains a valid OAuth 2.0 bearer access token, the Open Liberty OIDC client automatically validates it and creates an authenticated subject based on the token validation result. If the request does not contain an access token or the access token is invalid, then the Open Liberty OIDC client continues to redirect the user to an OIDC provider. This function enables the Open Liberty server to serve both the browser client and nonbrowser client like a RESTful client.

<openidConnectClient id="nocookie"
    ...
    inboundPropagation="supported"
    ...
</openidConnectClient>

Modify the context root

If your hosting environment does not allow access to the /oidcclient context root, you can modify the context root by configuring the oidcClientWebapp element. By default, the Open Liberty OIDC client redirect servlet listens on the /oidcclient context root, and the redirect URL format is https://host_name: ssl_port/oidcclient/redirect/configuration_ID. If you cannot use this context root, you can set a different context root.

For example, if your hosting environment requires that you use the /example/openid context root, add the following element in your server.xml file.

<oidcClientWebapp contextPath="/example/openid" />

The resulting redirect URL format is https://host_name: ssl_port/example/openid/redirect/configuration_ID.

Pass request parameters to OpenID Connect

To provide extra authorization parameters to the OP, configure authzParameter elements. For example, the following configuration properties pass api_key and account parameters to the authorization endpoint.

<authzParameter name="api_key" value="567890" />
<authzParameter name="account" value="123456" />

To configure parameters for the token endpoint, use the tokenParameter element.

Check the access token for user and group information

If userIdentifier or groupIdentifier values are not found in the ID token, Open Liberty can also check in the access token and the UserInfo endpoint.

Set the tokensOrderToFetchCallerClaims attribute to AccessToken IDToken Userinfo, as shown in the following example.

<openidConnectClient tokensOrderToFetchCallerClaims="AccessToken IDToken Userinfo"  userIdentifier="unique_name" groupIdentifier="aud" ... />

In this example, Open Liberty checks for userIdentifier and groupIdentifier values first in the access token, then the ID token, and lastly, calls the UserInfo endpoint. If the values are not found in any of those locations, an unauthorized response code is returned.

If the tokensOrderToFetchCallerClaims attribute is not specified, the default value is IDToken and Open Liberty checks only the ID token for user and group information.

Feature configuration elements

Liberty API packages provided by this feature

Features that this feature enables

Supported Java versions

  • JavaSE-1.8

  • JavaSE-11.0

  • JavaSE-17.0

  • JavaSE-21.0

  • JavaSE-22.0

Developing a feature that depends on this feature

If you are developing a feature that depends on this feature, include the following item in the Subsystem-Content header in your feature manifest file.

com.ibm.websphere.appserver.openidConnectClient-1.0; type="osgi.subsystem.feature"