Authenticating to the LDAP by Using the JNDI

In the JNDI, authentication information is specified in environment properties. When you create an initial context by using the InitialDirContext class (or its superclass or subclass), you supply a set of environment properties, some of which might contain authentication information. You can use the following environment properties to specify the authentication information.


• Context.SECURITY_AUTHENTICATION ("java.naming.security.authentication").
Specifies the authentication mechanism to use. For the Sun LDAP service provider, this can be one of the following strings: "none", "simple", sasl_mech, where sasl_mech is a space-separated list of SASL mechanism names. See the next section for a description of these strings.

• Context.SECURITY_PRINCIPAL ("java.naming.security.principal").
Specifies the name of the user/program doing the authentication and depends on the value of the Context.SECURITY_AUTHENTICATION property. See the next few sections in this lesson for details and examples.

• Context.SECURITY_CREDENTIALS ("java.naming.security.credentials").
Specifies the credentials of the user/program doing the authentication and depends on the value of the Context.SECURITY_AUTHENTICATION property. See the next few sections in this lesson for details and examples.

When the initial context is created, the underlying LDAP service provider extracts the authentication information from these environment properties and uses the LDAP "bind" operation to pass them to the server. The following example(refer Simple.java) shows how, by using a simple clear-text password, a client authenticates to an LDAP server.

// Set up the environment for creating the initial context

Hashtable env = new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
env.put(Context.PROVIDER_URL, "ldap://localhost:389/o=JNDITutorial");
// Authenticate as S. User and password "mysecret"
env.put(Context.SECURITY_AUTHENTICATION, "simple");
env.put(Context.SECURITY_PRINCIPAL, "cn=S. User, ou=NewHires, o=JNDITutorial");
env.put(Context.SECURITY_CREDENTIALS, "mysecret");
// Create the initial context
DirContext ctx = new InitialDirContext(env);
// ... do something useful with ctx