Configuring Inbound Authentication for a Service Provider

You can configure the following in inbound authentication.

Configuring SAML2 web single-sign-on

1. Expand the SAML2 Web SSO Configuration and click Configure.
2. Fill in the form that appears.
    
3. Click Register.

The following points should be taken into consideration when filling the above New Service Provider form.

• Specify the Issuer. This is the <saml:Issuer> element that contains the unique identifier of the service provider. This is also the issuer value specified in the SAML Authentication Request issued by the service provider. When configuring single-sign-on across Carbon servers, ensure that this value is equal to the ServiceProviderID value mentioned in the <IS_HOME>/repository/conf/security/authenticators.xml file of the relying party Carbon server.

• Specify the Assertion Consumer URL. This is the URL to which the browser should be redirected to after the authentication is successful. This is the Assertion Consumer Service (ACS) URL of the service provider. The identity provider redirects the SAML2 response to this ACS URL. However, if the SAML2 request is signed and SAML2 request contains the ACS URL, the Identity Server will honor the ACS URL of the SAML2 request. It should have this format: https://(host-name):(port)/acs.

• Specify the NameID format. This defines the name identifier formats supported by the identity provider. The service provider and identity provider usually communicate with each other regarding a specific subject. That subject should be identified through a Name-Identifier (NameID) , which should be in some format so that It is easy for the other party to identify it based on the format. Name identifiers are used to provide information regarding a user. 

  About NameID formats

  For SSO interactions, you can use the following types of NameID formats.

  • urn:oasis:names:tc:SAML:2.0:nameid-format:persistent
  • urn:oasis:names:tc:SAML:2.0:nameid-format:transient
  • urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress
  • urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified
  • urn:oasis:names:tc:SAML:1.1:nameid-format:X509SubjectName
  • urn:oasis:names:tc:SAML:1.1:nameid-format:WindowsDomainQualifiedName
  • urn:oasis:names:tc:SAML:2.0:nameid-format:kerberos
  • urn:oasis:names:tc:SAML:2.0:nameid-format:entity

  This specifies the name identifier format that the Identity Server wants to receive in the subject of an assertion from a particular identity provider. The following is the default format used by the identity provider.

  • urn:oasis:names:tc:SAML:1.1:nameid-format:emailAddress

• Select Use fully qualified username in the NameID if that feature is required. A fully qualified username is basically the user name with the user store domain. In short, the username must be in the following format: {user store domain}{user name}. 

• Select Enable Response Signing to sign the SAML2 Responses returned after the authentication process.

• Select Enable Assertion Signing to sign the SAML2 Assertions returned after the authentication. SAML2 relying party components expect these assertions to be signed by the Identity Server.

• Select Enable Signature Validation in Authentication Requests and Logout Requests if you need this functionality configured. This specifies whether the identity provider must validate the signature of the SAML2 authentication request and the SAML2 logout request that are sent by the service provider. 

• Enable Assertion Encryption, if you wish to encrypt the assertion.
• Select the Certificate Alias from the dropdown. This is used to validate the signature of SAML2 requests and is used to generate encryption. Basically the service provider’s certificate must be selected here. Note that this can also be the Identity Server tenant's public certificate in a scenario where you are doing a tenant specific configuration.

• Select Enable Single Logout so that all sessions are terminated once the user signs out from one server. If single logout is enabled, the identity provider sends logout requests to all service providers. Basically, the identity provider acts according to the single logout profile. If the service provider supports a different URL for logout, you can enter a Custom Logout URL for logging out. If you do not specify this URL, the identity provider uses the Assertion Consumer Service (ACS) URL. 

• Select Enable Attribute Profile to enable this and add a claim by entering the claim link and clicking the Add Claim button. The Identity Server provides support for a basic attribute profile where the identity provider can include the user’s attributes in the SAML Assertions as part of the attribute statement. Once you select the checkbox to Include Attributes in the Response Always, the identity provider always includes the attribute values related to the selected claims in the SAML attribute statement. 

• Select Enable Audience Restriction to restrict the audience. You may add audience members using the Audience text box and clicking the Add Audience button.

• Select Enable Recipient Validation if required. The recipient attribute of a SAML assertion contains the service provider's Assertion Consumer Service (ACS) URL, and the Identity Server, by default, sends the registered service provider's ACS URL as the recipient.

  Tip: There can be situations where the same SAML assertion can be consumed by multiple service providers. A scenario where we use SAML2 Bearer Grant is one such example. In such a scenario the assertion consumer endpoints of all those intended service providers should be added as recipients. Enabling recipient validation allows you to do just that.

• Select the Enable IdP Initiated SSO checkbox to enable this functionality. When this is enabled, the service provider is not required to send the SAML2 request. 

<SSOService>
...
	<UseAuthenticatedUserDomainCrypto>true<UseAuthenticatedUserDomainCrypto>
</SSOService>

Configuring OAuth/OpenID Connect

OAuth provides a method for clients to access server resources on behalf of a resource owner (such as a different client or an end-user). It also provides a process for end-users to authorize third-party access to their server resources without sharing their credentials (typically, a username and password pair), using user-agent redirections.

OpenID Connect is a simple identity layer on top of the OAuth 2.0 protocol. It allows Clients to verify the identity of the End-User based on the authentication performed by an Authorization Server, as well as to obtain basic profile information about the End-User in an interoperable and REST-like manner.

OpenID Connect allows clients of all types, including Web-based, mobile, and JavaScript clients, to request and receive information about authenticated sessions and end-users. The specification suite is extensible, allowing participants to use optional features such as encryption of identity data, discovery of OpenID Providers, and session management, when it makes sense for them.

To enable OAuth support for your client application, you must first register your application by providing an application name and a callback URL. Follow the instructions below to add a new application.

1. Expand the OAuth/OpenID Connect Configuration and 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.
   
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.

   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/ directory and change the <TokenPersistenceProcessor> property as follows:

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

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

• 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.
• The Callback Url is the exact location in the service provider's application where an access token would be sent. This is a required field and 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.
• The following are the grant types that are used to get the access token.
  • Code - Entering the user name and password required at the service provider will result in a code being generated. This code can be used to obtain the access token.
  • Implicit - This is similar to the code grant type, but instead of generating a code, this directly provides the access token.
  • Password - This authenticates the user using the password provided and the access token is provided.
  • 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.
  • 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.
  • SAML - This uses SAML as the grant type to obtain the access token.
  • IWA-NTLM - This is similar to the password grant type, but it is specific to Microsoft Windows users.

Configuring WS-Trust Security Token Service

This requires registration of relying party endpoint addresses and their corresponding public certificates. In this scenario, STS generates a symmetric key and encrypts it with the public key of the relying party. This is included in the subject confirmation section of the SAML token, which is validated at the relying party end.

Follow the instructions below to configure STS for obtaining tokens.

1. Expand the WS-Trust Security Token Service Configuration and click Configure.
2. Specify the required information in the form that appears.
   
   • Endpoint Address - Relying party service endpoint where the token is being delivered to. This is a required field.
   • Certificate Alias - Corresponding public certificate for the service endpoint.
3. Click Apply. The following information is added to your service provider.
    

Configuring WS-Federation (Passive) and OpenID

1. Expand the WS-Federation (Passive) Configuration and OpenID Configuration.
2. Enter the identifier for the Passive STS Realm and the OpenID Realm. These identifiers need to be specified as identification when the service provider reaches out to the Identity Server.