/*
* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.ldap.authentication;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.ldap.NamingException;
import org.springframework.ldap.core.DirContextAdapter;
import org.springframework.ldap.core.DirContextOperations;
import org.springframework.ldap.core.DistinguishedName;
import org.springframework.ldap.core.support.BaseLdapPathContextSource;
import org.springframework.ldap.support.LdapUtils;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.ldap.ppolicy.PasswordPolicyControl;
import org.springframework.security.ldap.ppolicy.PasswordPolicyControlExtractor;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import javax.naming.directory.Attributes;
import javax.naming.directory.DirContext;
/**
* An authenticator which binds as a user.
*
* @author Luke Taylor
*
* @see AbstractLdapAuthenticator
*/
public class BindAuthenticator extends AbstractLdapAuthenticator {
// ~ Static fields/initializers
// =====================================================================================
private static final Log logger = LogFactory.getLog(BindAuthenticator.class);
// ~ Constructors
// ===================================================================================================
/**
* Create an initialized instance using the {@link BaseLdapPathContextSource}
* provided.
*
* @param contextSource the BaseLdapPathContextSource instance against which bind
* operations will be performed.
*
*/
public BindAuthenticator(BaseLdapPathContextSource contextSource) {
super(contextSource);
}
// ~ Methods
// ========================================================================================================
public DirContextOperations authenticate(Authentication authentication) {
DirContextOperations user = null;
Assert.isInstanceOf(UsernamePasswordAuthenticationToken.class, authentication,
"Can only process UsernamePasswordAuthenticationToken objects");
String username = authentication.getName();
String password = (String) authentication.getCredentials();
if (!StringUtils.hasLength(password)) {
logger.debug("Rejecting empty password for user " + username);
throw new BadCredentialsException(messages.getMessage(
"BindAuthenticator.emptyPassword", "Empty Password"));
}
// If DN patterns are configured, try authenticating with them directly
for (String dn : getUserDns(username)) {
user = bindWithDn(dn, username, password);
if (user != null) {
break;
}
}
// Otherwise use the configured search object to find the user and authenticate
// with the returned DN.
if (user == null && getUserSearch() != null) {
DirContextOperations userFromSearch = getUserSearch().searchForUser(username);
user = bindWithDn(userFromSearch.getDn().toString(), username, password,
userFromSearch.getAttributes());
}
if (user == null) {
throw new BadCredentialsException(messages.getMessage(
"BindAuthenticator.badCredentials", "Bad credentials"));
}
return user;
}
private DirContextOperations bindWithDn(String userDnStr, String username,
String password) {
return bindWithDn(userDnStr, username, password, null);
}
private DirContextOperations bindWithDn(String userDnStr, String username,
String password, Attributes attrs) {
BaseLdapPathContextSource ctxSource = (BaseLdapPathContextSource) getContextSource();
DistinguishedName userDn = new DistinguishedName(userDnStr);
DistinguishedName fullDn = new DistinguishedName(userDn);
fullDn.prepend(ctxSource.getBaseLdapPath());
logger.debug("Attempting to bind as " + fullDn);
DirContext ctx = null;
try {
ctx = getContextSource().getContext(fullDn.toString(), password);
// Check for password policy control
PasswordPolicyControl ppolicy = PasswordPolicyControlExtractor
.extractControl(ctx);
logger.debug("Retrieving attributes...");
if (attrs == null || attrs.size()==0) {
attrs = ctx.getAttributes(userDn, getUserAttributes());
}
DirContextAdapter result = new DirContextAdapter(attrs, userDn,
ctxSource.getBaseLdapPath());
if (ppolicy != null) {
result.setAttributeValue(ppolicy.getID(), ppolicy);
}
return result;
}
catch (NamingException e) {
// This will be thrown if an invalid user name is used and the method may
// be called multiple times to try different names, so we trap the exception
// unless a subclass wishes to implement more specialized behaviour.
if ((e instanceof org.springframework.ldap.AuthenticationException)
|| (e instanceof org.springframework.ldap.OperationNotSupportedException)) {
handleBindException(userDnStr, username, e);
}
else {
throw e;
}
}
catch (javax.naming.NamingException e) {
throw LdapUtils.convertLdapException(e);
}
finally {
LdapUtils.closeContext(ctx);
}
return null;
}
/**
* Allows subclasses to inspect the exception thrown by an attempt to bind with a
* particular DN. The default implementation just reports the failure to the debug
* logger.
*/
protected void handleBindException(String userDn, String username, Throwable cause) {
if (logger.isDebugEnabled()) {
logger.debug("Failed to bind as " + userDn + ": " + cause);
}
}
}