Configuring OAuth2-OpenID Connect Single-Sign-On

OAuth 2.0 has three main phases. They are; requesting an Authorization Grant, exchanging the Authorization Grant for an Access Token and accessing the resources using this Access Token. OpenID Connect is another identity layer on top of OAuth 2.0. OAuth applications can get authentication event information over the IDToken and can get the extra claims of the authenticated user from the OpenID Connect UserInfo endpoint.

To enable OAuth support for your client application, you must first register your application. Follow the instructions below to add a new application.

Let's get started to configure the service provider you created!

1. Expand the Inbound Authentication Configuration section and then expand OAuth/OpenID Connect Configuration. Click Configure.

2. Fill in the form that appears. For the Allowed Grant Types you can disable the ones you do not require or wish to block.

   Note: The grant type highlighted below is a custom grant type. This will only appear on the UI if you have configured the JWT grant type. The value specified in the <GrantTypeName> property of the identity.xml file when creating the custom grant type is the value that will appear on the UI. For more information on writing a custom grant type, see Writing a Custom OAuth 2.0 Grant Type.

   

   When filling out the New Application form, the following details should be taken into consideration.

   Field	Notes
   OAuth Version	Selecting OAuth Version as 1.0a removes all the configurable Allowed Grant Types. This is because this version of OAuth does not support grant types.
   Callback Url	This is the exact location in the service provider's application where an access token would be sent. This is a required field (if the grant type is anything other than 'Code' or 'Implicit') and it is important to configure, as it is imperative that the service provider receives the access token. This is necessary for security purposes to ensure that the token is not compromised. Configure multiple callback URLs From IS 5.2.0 onwards, regex-based consumer URLs are supported when defining the callback URL. This enables you to configure multiple callback URLs for one application by entering a regex pattern as the value for the callback URL field. For example, if you have two service providers that use the same application, you can now define a regex pattern which will work for both callback URLs instead of having to configure two different applications for the two service providers. Assume the two callback URLs for your two service providers are as follows: https://myapp.com/callback https://testapp:8000/callback To configure the callback URL to work for both of these URLs, set it using a regex pattern as follows: regexp=(https://((myapp\.com)|(testapp:8000))(/callback)) You must have the prefix 'regexp=' before your regex pattern. To define a normal URL, you can specify the callback URL without this prefix. You can also configure a regex pattern that contains dynamic values as seen below. regexp=https://mchcon.clance.local\?id=(.*)
   Allowed Grant Types - The following are the grant types that are used to get the access token:
   Code	Entering the username and password required at the service provider will result in a code being generated. This code can be used to obtain the access token. For more information on this grant type, see this Authorization Code specification.
   Implicit	This is similar to the code grant type, but instead of generating a code, this directly provides the access token. For more information on this grant type, see this Implicit Grant specification.
   Password	This authenticates the user using the password provided and the access token is provided. For more information on this grant type, see this Resource Owner Password Credentials Grant specification.
   Client Credential	This is the grant type for the client key and client secret. If these two items are provided correctly by the service provider, the access token is sent. For more information on this grant type, see this Client Credentials specification.
   Refresh Token	This will enable the user to obtain an access token by using the refresh token once the originally provided access token is used up. For more information on this grant type, see this Refresh Token specification.
   SAML	This uses SAML assertion to obtain the access token. For more information on this grant type, see this SAML2 Bearer specification.
   IWA-NTLM	This is similar to the password grant type, but it is specific to Microsoft Windows users.
   urn:ietf:params:oauth:grant-type:jwt-bearer	This is a custom grant type. It uses a JWT token to obtain the access token. For more information about this grant type, see this JWT specification.
   PKCE Mandatory	Select this if you are using the Code grant type. PKCE is a recommended security measure used to mitigate a code interception attack. See Mitigating Authorization Code Interception Attacks for more information.
   Support PKCE 'Plain' Transform Algorithm	Select this if you are using PKCE.
   User Access Token Expiry Time, Application Access Token Expiry Time, Refresh Token Expiry Time	Set the validity period (in seconds) for User Access Token, Application Access Token, and Refresh Token.
   Enable Audience Restriction	Select this to enable audience restrictions for OAuth applications. If necessary, you can add multiple audiences. To add an audience, specify a required Audience value and click Add. All audience values that you add would be available in the ID token generated for the corresponding application. Before you add an audience, ensure that the following property is set to true in the <IS_HOME>/repository/conf/identity/identity.xml file. <EnableAudiences>true</EnableAudience>

3. Click Add. The following information is added for your service provider.
   
   • OAuth Client Key - This is the client key of the service provider, which will be checked for authentication by the Identity Server before providing the access token.
   • OAuth Client Secret - This is the client secret of the service provider, which will be checked for authentication by the Identity Server before providing the access token. Click the Show button to view the exact value of this.
   • Actions - 

     • Edit: Click to edit the OAuth/OpenID Connect Configurations

     • Revoke: Click to revoke (deactivate) the OAuth application. This action revokes all tokens issued for this application. In order to activate the application, you have to regenerate the consumer secret. 

     • Regenerate Secret: Click to regenerate the secret key of the OAuth application. 

     • Delete: Click to delete the OAuth/OpenID Connect Configurations

   Tip: The OAuth client key and client secret are stored in plain text. To encrypt the client secret, access token and refresh token, do the following:

   Open the identity.xml file found in the <IS_HOME>/repository/conf/identity directory and change the <TokenPersistenceProcessor> property as follows:

   <TokenPersistenceProcessor>org.wso2.carbon.identity.oauth.tokenprocessor.EncryptionDecryptionPersistenceProcessor</TokenPersistenceProcessor>

   After updating the configuration, make sure to restart the server for the changes to be applied on WSO2 IS.

Configuring token issuer at the service provider level

In WSO2 Identity Server, token issuer is a server level configuration that is configured in the <IS_HOME>/repository/conf/identity/identity.xml file.

If you want to configure token issuer at the service provider level, you need to apply the WUM update for IS 5.5.0 released on the 15th of June 2018.

You can deploy a WUM update into production only if you have a paid subscription. If you do not have a paid subscription, you can use this feature when the next version of WSO2 Identity Server is released.

When you apply the WUM update, you will see the following configuration in the <IS_HOME>/repository/conf/identity/identity.xml file:

<!--SupportedTokenTypes>
            <SupportedTokenType>
                <TokenTypeName>Default</TokenTypeName>
                <TokenTypeImplClass>org.wso2.carbon.identity.oauth2.token.OauthTokenIssuerImpl</TokenTypeImplClass>
                <PersistAccessTokenAlias>true</PersistAccessTokenAlias>
            </SupportedTokenType>
            <SupportedTokenType>
                <TokenTypeName>JWT</TokenTypeName>
                <TokenTypeImplClass>org.wso2.carbon.identity.oauth2.token.JWTTokenIssuer</TokenTypeImplClass>
                <PersistAccessTokenAlias>true</PersistAccessTokenAlias>
            </SupportedTokenType>
        </SupportedTokenTypes-->

You will also see that JWT and Default are displayed as the Token Issuer options when you configure OAuth/OpenID Connect for a service provider. You can select an appropriate token issuer depending on your requirement:

• If you want to enable default token generation for a service provider, select Default as the Token Issuer. This is the default Token Issuer that is selected when you apply the WUM update.
  When you enable default token generation, the hash value of the token is stored in the ACCESS_TOKEN_HASH column, and the plain text token is stored in the ACCESS_TOKEN column
• If you want to enable JWT token generation for a service provider, select JWT as the Token Issuer.
  When you enable JWT token generation, the hash value of the JWT is stored in the ACCESS_TOKEN_HASH column, and the full JWT is stored in the ACCESS_TOKEN column.