Identity assertion to the downstream server


When a client authenticates to a server, the received credential is set. When the authorization engine checks the credential to determine whether access is permitted, it also sets the invocation credential. Identity assertion is the invocation credential that is asserted to the downstream server.

When a client authenticates to a server, the received credential is set. When the authorization engine checks the credential to determine whether access is permitted, it also sets the invocation credential so that if the EJB method calls another EJB method that is located on other servers, the invocation credential can be the identity used to invoke the downstream method. Depending on the RunAs mode for the enterprise beans, the invocation credential is set as the originating client identity, the server identity, or a specified different identity. Regardless of the identity that is set, when identity assertion is enabled, it is the invocation credential that is asserted to the downstream server.

The invocation credential identity is sent to the downstream server in an identity token. In addition, the sending server identity, including the password or token, is sent in the client authentication token when basic authentication is enabled. The sending server identity is sent through an SSL) client certification authentication when client certificate authentication is enabled. Basic authentication takes precedence over client certificate authentication.

Both identity tokens are needed by the receiving server to accept the asserted identity. The receiving server completes the following actions to accept the asserted identity:

Evaluation of the identity token consists of the following four identity formats that exist in an identity token:

WAS ND v7.0 servers that receive authentication information typically support all four identity types. The sending server decides which one is chosen, based on how the original client authenticated. The existing type depends on how the client originally authenticates to the sending server. For example, if the client uses SSL) client authentication to authenticate to the sending server, then the identity token sent to the downstream server contains the certificate chain. With this information, the receiving server can perform its own certificate chain mapping and interoperability is increased with other vendors and platforms.

After the identity format is understood and parsed, the identity maps to a credential. For an ITTPrincipal identity token, this identity maps one-to-one with the user ID fields.

For an ITTDistinguishedName identity token, the mapping depends on the user registry. For LDAP, the configured search filter determines how the mapping occurs. For LocalOS, the first attribute of the distinguished name (DN), which is typically the same as the common name, maps to the user ID of the registry.

Identity assertion is only available using the Common Secure Interoperability Version 2 (CSIv2) protocol.

There is a restriction for using identity assertion with KRB token to downstream. If we use identity assertion with Kerberos enabled, the identity assertion does not have the Kerberos authentication token (KRBAuthnToken) when going to downstream servers. It uses LTPA for authentication instead.



 

Related concepts


Authentication protocol for EJB security

 

Related tasks


Authenticate users