You can limit the access to your web server to certain users or groups. User-Group access control requires users to enter a username and password before gaining access to the server. The server compares the information in a client certificate, or the client certificate itself with a directory server entry.
The Administration Server uses only the basic authentication. If you wish to require client authentication on your Administration Server, you must manually edit the ACL files in obj.conf changing the method to SSL.
User-Group authentication is performed by the directory service configured for a server. For more details, see the section Configuring a Directory Service. The information that a directory service uses to implement access control can come from either of the following sources:
An internal flat file-type database
An external LDAP database
When the server uses an external LDAP-based directory service, it supports the following types of User-Group authentication methods for server instances:
When the server uses an internal file-based directory service, the User-Group authentication methods for server instances it supports include:
User-Group authentication requires users to verify their identity before they are able access to the Administration Server, or files and directories on the web site. During authentication, users enter username and password, using a client certificate, or digest authentication plug-in. To use a client certificate you require encryption. For information on encryption and using client certificates, see Chapter 5, J2SE-based Security for Web Container and Web Applications.
Default authentication is the preferred authentication method. The Default setting uses the default method in the obj.conf file, or “Basic” if there is no setting in the obj.conf file. If you select Default, the ACL rule does not specify a method in the ACL file. Choosing Default allows you to easily change the methods for all ACLs by editing one line in the obj.conf file.
Basic authentication is selected by default and requires users to enter a username and password to access the web server or web site. You must create and store a list of users and groups in an LDAP database, such as the Sun Java System Directory Server, or in a file. You must use either a directory server installed on a different server root than your web server, or a directory server installed on a remote machine.
When users attempt to access a resource that has User-Group authentication in the Administration Server or on your web site, the web browser displays a dialog box asking the user to enter a username and password. The server receives the information either encrypted or unencrypted, depending on whether encryption is turned on for the server.
If you use the Basic Authentication setting without SSL encryption, the username and password are sent as unencrypted text across the network. The network packets could be intercepted, and the username and password could be misused. Basic authentication is most effective when combined with SSL encryption, Host-IP authentication, or both. Use Digest Authentication to avoids this problem.
The following dialog appears when users authenticate their identity:
After you click OK, the following process is followed:
The Server Administration page, if authenticated to access the Sun Java System Web Administration Server
The file or directory listing requested, if logging in to a web site
A message denying access if the username or password are invalid
You can customize the access denied message received by unauthorized users using the Access Denied Response page.
The server can confirm users’ identities using security certificates in the following ways:
By using the information in the client certificate as proof of identity
By verifying a client certificate published in an LDAP directory (additional)
When you configure the server to use certificate information for authenticating the client, the server:
Checks first if the certificate is from a trusted CA. If not, the authentication fails and the transaction ends. To learn how to turn on client authentication, see Requiring Client Authentication.
Maps the certificate to a user’s entry using the certmap.conf file, if the certificate is from a trusted certificate authority (CA). To learn how to set up the certificate mapping file see Using the certmap.conf File.
Checks the ACL rules specified for a specific user if the certificate maps correctly. Even if the certificate maps correctly, ACL rules can deny the user access.
Requiring client authentication for controlling access to specific resources differs from requiring client authentication for all connections to the server. If you set the server to require client authentication for all connections, the client only needs to present a valid certificate issued by a trusted CA. If you set the server’s access control to use the SSL method for authentication of users and groups, the client needs to:
Present a valid certificate issued by a trusted CA
The certificate must be mapped to a valid user in LDAP
The access control list must evaluate properly
When you require client authentication with access control, you need to have SSL ciphers enabled for your web server. See Chapter 7, Using Certificates and Keys to learn how to enable SSL.
In order to successfully gain access to an SSL authenticated resource, the client certificate must be from a CA trusted by the web server. The client certificate needs to be published in a directory server if the web server’s certmap.conf file is configured to compare the client’s certificate in the browser with the client certificate in the directory server. However, the certmap.conf file can be configured to only compare selected information from the certificate to the directory server entry. For example, you could configure the certmap.conf file to only compare the user ID and email address in the browser certificate with the directory server entry. To learn more about the certmap.conf file and certificate mapping, see Chapter 7, Using Certificates and Keys.
Only the SSL authentication method requires you to modify the certmap.conf file, because the certificate is checked against the LDAP directory. Requiring client authentication for all connections to the server does not. If you choose to use client certificates, you should increase the value of the AcceptTimeout directive in magnus.conf.
The Sun Java System Web Server 6.1 can be configured to perform digest authentication using either an LDAP-based or a file-based directory service.
Digest authentication allows the user to verify identity based on username and password without sending the username and password as cleartext. The browser uses the MD5 algorithm to create a digest value using the user’s password and some information provided by the Web Server.
When the server uses an LDAP-based directory service to perform digest authentication, this value is also computed on the server using the Digest Authentication plug-in, and is there compared against the digest value provided by the client. If the digest values match, the user is authenticated. In order for this process to work, the directory server needs access to the user’s password in cleartext. The Sun Java System Directory Server includes a reversible password plug-in using a symmetric encryption algorithm to store data in an encrypted form, that can later be decrypted to its original form. Only the Directory Server holds the key to the data.
For LDAP-based digest authentication, you need to enable the reversible password plug-in and the digestauth-specific plug-in included with Sun Java System Web Server 6.1. To configure the web server to process digest authentication, set the digestauth property of the database definition in dbswitch.conf.
The server tries to authenticate against the LDAP database based upon the ACL method specified, as shown in Digest Authentication. If you do not specify an ACL method, the server will use either digest or basic when authentication is required, or basic if authentication is not required. This is the preferred method.Table 9–1 Digest Authentication Challenge Generation
Digest Authentication Supported by Authentication Database
Digest Authentication Not Supported by Authentication Database
digest and basic
Checking for Authorization request header. If not found, a 401 response is generated with a Digest challenge, and the process ends.
Checking for Authorization type. If Authentication type is Digest then:
You can configure the time the nonce remains fresh by changing the value of the parameter DigestStaleTimeout in the magnus.conf file, located in server_root/https-server_name/config/. To set the value, add the following line to magnus.conf:
where seconds represents the number of seconds the nonce will remain fresh. After the specified seconds elapse, the nonce expires and new authentication is required from the user.
Checks realm. If it does not match, generates 401 response, and process stops.
verifies the existence of user in the LDAP directory if the authentication directory is LDAP-based, or verifies the existence of user in file database if the authentication directory is file-based. If not found, generates 401 response, and the process stops.
Constructs Authorization-Info header and inserts it into server headers.
For digest authentication using an LDAP-based directory service, you need to install the digest authentication plug-in. This plug-in computes a digest value on the server side, and compares this against the digest value provided by the client. If the digest values match, the user is authenticated.
If you’re using a file-based authentication database, you don’t need to install the digest authentication plug-in.
The Digest Authentication plug-in consists of a shared library found in the following files:
Make sure this shared library resides on the same server machine that the Sun Java System Directory Server is installed on.
Make sure you know the Directory Manager password.
Modify the libdigest-plugin.ldif file changing all references to the /path/to to the location where you installed the digest plug-in shared library.
libdigest-plugin.ldif is available at server-root/plugins/digest/libdigest-plugin.ldif.
To install the plug-in, enter the following command:
% ldapmodify -D "cn=Directory Manager" -w password -a < libdigest-plugin.ldif
You need to copy several .dll files from the Sun Java System Web Server installation to your Sun Java System Directory Server server machine in order for Sun Java System Directory Server to start properly with the Digest plug-in.
Access the shared libraries on the Sun Java System Web Server installation in:
Copy the following files:
Paste them into either:
Launch the Sun Java System Directory Server Console.
Open your iDS 5.0 instance.
Select the Configuration tab.
Click on the + sign next to plug-ins.
Select the DES plug-in.
Choose Add to add a new attribute.
Restart your Sun Java System Directory Server instance.
The iplanetReversiblePasswordobject attribute stores the password for digest authentication. To set a digest authentication password in the iplanetReversiblePassword attribute for a user, your entry must include the iplanetReversiblePasswordobject object.
You can create a custom authentication method using the access control API.