Question

I’m trying to connect to an Active Directory from Activiti, using Apache Directory’s LDAP API. I think I’ve managed to authenticate my user, but subsequent queries for users finds nothing.

Here’s my Java code:

package com.abc.activiti.ldap;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.identity.User;
import org.activiti.engine.impl.Page;
import org.activiti.engine.impl.UserQueryImpl;
import org.activiti.engine.impl.persistence.entity.UserEntity;
import org.activiti.engine.impl.persistence.entity.UserManager;
import org.apache.directory.ldap.client.api.LdapConnection;
import org.apache.directory.ldap.client.api.exception.LdapException;
import org.apache.directory.ldap.client.api.message.BindResponse;
import org.apache.directory.ldap.client.api.message.SearchResponse;
import org.apache.directory.ldap.client.api.message.SearchResultEntry;
import org.apache.directory.shared.ldap.cursor.Cursor;
import org.apache.directory.shared.ldap.entry.EntryAttribute;
import org.apache.directory.shared.ldap.filter.SearchScope;
import org.apache.directory.shared.ldap.message.ResultCodeEnum;
import org.apache.mina.core.session.IoSession;
import org.slf4j.LoggerFactory;
import org.slf4j.Logger;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class LDAPUserManager extends UserManager {
    private final static Logger logger = LoggerFactory.getLogger(LDAPUserManager.class);

    private LDAPConnectionParams ldapConnectionParams;

    public LDAPUserManager(LDAPConnectionParams ldapConnectionParams) {
        this.ldapConnectionParams = ldapConnectionParams;
    }

    public Boolean checkPassword(String userId, String password) {
        Boolean result;
        LdapConnection connection;

        String userDN = ldapConnectionParams.getUserPrefix() + "=" +
                userId + "," + ldapConnectionParams.getUserGroup();
        logger.debug("Checking password, using connection string: '" + userDN + "'");
        try {
            connection = openConnection();
            BindResponse bindResponse = connection.bind(userDN, password);
            result = bindResponse.getLdapResult().getResultCode() == ResultCodeEnum.SUCCESS;
        } catch (LdapException e) {
            throw new ActivitiException("LDAP exception while binding", e);
        } catch (IOException e) {
            throw new ActivitiException("IO exception while binding", e);
        }
        // TODO: move this into a finally clause above
        closeConnection(connection);

        return result;
    }

    public List<User> findUserByQueryCriteria(Object o, Page page) {
        List<User> result = new ArrayList<User>();

        UserQueryImpl userQuery = (UserQueryImpl)o;
        StringBuilder queryString = new StringBuilder();
        queryString.append("(").append(ldapConnectionParams.getUserPrefix()).append("=")
                .append(userQuery.getId()).append(")");

        logger.debug("Looking for users: '" + queryString + "'");
        LdapConnection connection;

        try {
            connection = openConnection();
            Cursor<SearchResponse> responseCursor = connection.search(
                    ldapConnectionParams.getUserGroup(), queryString.toString(),
                    SearchScope.ONELEVEL,
                    "cn", "sAMAccountName", "sn");

            logger.debug("Got cursor: " + responseCursor);

            for (SearchResponse response : responseCursor) {
                logger.debug("It's a rsponse: " + response);
            }

            int maxUsers = 10;
            while (responseCursor.next() && maxUsers-- > 0) {
                User user = new UserEntity();
                SearchResultEntry searchResponse = (SearchResultEntry)responseCursor.get();
                logger.debug("Got item: " + searchResponse);
                result.add(user);
            }
            responseCursor.close();
        } catch (LdapException e) {
            throw new ActivitiException("While searching for user in LDAP", e);
        } catch (Exception e) {
            throw new ActivitiException("While searching for user in LDAP", e);
        }
        // TODO: move this into a finally clause above
        closeConnection(connection);
        logger.debug("Returning users: " + result);
        return result;
    }

    private void closeConnection(LdapConnection connection) {
        try {
            connection.unBind();
        } catch (Exception e) {
            e.printStackTrace();
        }
        try {
            connection.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private LdapConnection openConnection() throws LdapException, IOException {
        LdapConnection connection = new LdapConnection(
                ldapConnectionParams.getLdapServer(),
                ldapConnectionParams.getLdapPort()) {

            public void exceptionCaught(IoSession ioSession, Throwable throwable) throws Exception {
                logger.error("Exception thrown in " + ioSession, throwable);
            }
        };
        connection.connect();
        return connection;
    }

}

I read some stuff from spring bean definitions:

<property name="ldapServer" value="secret"/>
<property name="ldapPort" value="389"/>
<property name="ldapUser" value="CN=Stefan Blixt,OU=x,OU=x,OU=x,DC=x,DC=x"/>
<property name="ldapPassword" value="secret"/>
<property name="userGroup" value="OU=x,OU=x,OU=x,DC=x,DC=x"/>
<property name="userPrefix" value="CN"/>

Activiti will first run checkPassword(), which returns true, then it will run findUserByQueryCriteria(), which outputs this:

DEBUG: com.abc.activiti.ldap.LDAPUserManager - Looking for users: '(CN=Stefan Blixt)'
DEBUG: com.abc.activiti.ldap.LDAPUserManager - Got cursor: org.apache.directory.ldap.client.api.SearchCursor@1e3940a
DEBUG: com.abc.activiti.ldap.LDAPUserManager - Returning users: []

I have managed to connect and do this kind of query in Apache Directory Studio:

That one will give me a result with the entry for Stefan Blixt.

I’ve edited some paths above for privacy.

Any ideas? Are there any classic culprits that may result in zero results when doing an LDAP user search? I’ve tried using uid, sAMAccountName etc when searching – always the same result.

Answer 1

It appears that findUserByQueryCriteria is creating a new LdapConnection and not doing a bind() on it. Perhaps your AD server does not allow anonymous queries.