16 Developing Authentication

16.2.3.1 The Identity Store Login Module

A JavaSE application can use a stack of login modules to authenticate its users; each module in the stack performs its own computations independently from the others in the stack. These and other services are specified in the file jps-config-jse.xml.

OPSS APIs includes the interface oracle.security.jps.service.login.LoginService which allows a JavaSE application to invoke not just all login modules in a stack, but a subset of them in a prescribed order.

The name of the jps context (defined in the configuration file jps-config-jse.xml) passed to the method LoginContext in the LoginService interface (which is) determines the stack of login modules that an application uses.

The standard JAAS API LoginContext can also be user to invoke the login modules defined in the default context.

The sequence in which a jps context lists the login modules in a stack is significant, since the authentication algorithm takes this order into account in addition to other data, such as the flag that identifies the module security level (required, sufficient, requisite, or optional).

Out-of-the-box, the identity store service is file-based, its contents being provisioned the file system-jazn-data.xml, but it can be reconfigured to be an LDAP-based identity store.

OPSS supports the Identity Store login module in JavaSE applications, which can be used for authentication or identity assertion.

Identity Store Login Module

The class associated with this login module is the following:

oracle.security.jps.internal.jaas.module.idstore.IdStoreLoginModule

An instance of this module is configured in the file jps-config-jse.xml as illustrated in the following fragment:

<serviceInstance name="idstore.loginmodule" provider="jaas.login.provider">
  <description>Identity Store Login Module</description>
  <property name="loginModuleClassName" value="oracle.security.jps.internal.jaas.module.idstore.IdStoreLoginModule"/>
  <property name="jaas.login.controlFlag" value="REQUIRED"/>
</serviceInstance>

Properties specific to this login module include the following:

remove.anonymous.role (defaults to true)
add.application.role (defaults to true)

16.2.3.2 Using the Identity Store Login Module for Authentication

This section illustrates the use of the Identity Store login module for basic username and password authentication.

Invoke IdStoreLoginModule

The following code fragment illustrates how to set a callback handler and a context:

import javax.security.auth.Subject;
import javax.security.auth.login.LoginContext;

Subject sub = new Subject();
CallbackHandler cbh = new YourCallbackHandler();
LoginContext context = new LoginContext(appName, subject,  cbh);
context.login();

The callback handler must be able to handle NameCallback and PasswordCallback.

Configure jps-config-jse.xml

The following jps-config-jse.xml fragment illustrates the configuration of the context appName:

<jpsContext name="appName">
   <serviceInstanceRef ref="jaaslm.idstore1"/>
</jpsContext>

<serviceProvider type="JAAS_LM" name="jaaslm.idstore" 
      class="oracle.security.jps.internal.jaas.module.idstore.IdStoreLoginModule">
   <description>Identity Store-based LoginModule
   </description>
</serviceProvider>

<serviceInstance name="jaaslm.idstore1" provider="jaaslm.idstore">
   <property name="jaas.login.controlFlag" value="REQUIRED"/>
   <property name="debug" value="true"/>
   <property name="addAllRoles" value="true"/>
</serviceInstance>

Write the Callback Handler

The following code snippet illustrates a callback handler able to handle name and password callback:

import javax.security.auth.callback.*;
import java.io.IOException; 
public class SampleCallbackHandler implements CallbackHandler {
//For name/password callbacks
private String name = null;private char[] password = null; 
public SampleCallbackHandler(String name, char[] pwd) { 
   if (name == null || name.length() == 0 )         
      throw new IllegalArgumentException("Invalid name ");
   else 
      this.name = name; 
   if (pwd == null || pwd.length == 0)
      throw new IllegalArgumentException("Invalid password ");
   else
      this.password = pwd;
}
public String getName() {
   return name;
   } public char[] getPassword()  {
   return password;
 }    
public void handle(Callback[] callbacks) 
   throws IOException, UnsupportedCallbackException {
   if (callbacks != null && callbacks.length > 0) {
      for (Callback c : callbacks) {
      if (c instanceof NameCallback) {
            ((NameCallback) c).setName(name);
            } 
   else 
      if (c instanceof PasswordCallback) {
         ((PasswordCallback) c).setPassword(password);
              }           
   else {
      throw new UnsupportedCallbackException(c);
 }
          }
      }
  }
}

16.2.3.3 Using the Identity Login Module for Assertion

To use the Identity Store login module for assertion, a developer must:

• Provide an IdentityAssertion permission with execute action, so the permission oracle.security.jps.JpsPermission can execute the login module for assertion.

• Implement a callback handler that extends the class oracle.security.jps.callback.IdentityCallback.

The above two requirements are illustrated in the following code and configuration samples.

Provisioning the JpsPermission

The following configuration sample illustrates a grant allowing the code MyApp the required JpsPermission to execute the assertion login module:

<grant>
  <grantee>
    <codesource>
      <url>file:${domain.home}/servers/MyApp/-</url>
    </codesource>
  </grantee>
  <permissions>
    <permission>
      <class>oracle.security.jps.JpsPermission</class>
      <name>IdentityAssertion</name>
      <actions>execute</actions>
    </permission>
  </permissions>
</grant>

The following configuration sample illustrates a grant allowing the principal jdoe the required JpsPermission to execute the assertion login module:

<grant>
  <grantee>
    <principals>
      <principal>
        <class>weblogic.security.principal.WLSUserImpl</class>
        <name>jdoe</name>
      </principal>
    </principals>
  </grantee>
  <permissions>
    <permission>
      <class>oracle.security.jps.JpsPermission</class>
      <name>IdentityAssertion</name>
      <actions>execute</actions>
    </permission>
  </permissions>
</grant>

Implementing the CallbackHandler

The following code fragment illustrates the implementation of a handler and the method handle, and how to instantiate it:

import oracle.security.jps.callback.IdentityCallback;
import javax.security.auth.Subject;
import javax.security.auth.login.LoginContext;
 
class MyAssertionCallbackHandler extends CallbackHandler {
        private String name = null;
 
        public MyAssertionCallbackHandler(String name) {
          this.name = name;
        }
 
        public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
            for (Callback callback : callbacks) {
                if (callback instanceof IdentityCallback) {
                    IdentityCallback idcb = (IdentityCallback) callback;
                    idcb.setIdentity(name);
                } else {
                    //throw exception
                }
            }
        }
}
 
CallbackHandler cbh = new  MyAssertionCallbackHandler("name");
Subject sub = new Subject();

// The first parameter must be the name of the jpsContext in which the
// IdStore Login Module is referrenced
LoginContext context = new LoginContext("myContext", sub,  cbh);

context.login();
Subject s = context.getSubject();
...