Install LDAP for use as external authentication

By Malte Sussdorff

OpenACS docs are written by the named authors, and may be edited by OpenACS documentation staff.

This step by step guide on how to use LDAP for external authentication using the LDAP bind command, which differs from the approach usually taken by auth-ldap. Both will be dealt with in these section

  1. Install openldap. Download and install ns_ldap

    [root aolserver]# cd /usr/local/src/
              [root src]# wget ftp://ftp.openldap.org/pub/OpenLDAP/openldap-release/openldap-2.2.17.tgz
              [root src]# tar xvfz openldap-2.2.17.tgz
              [root src]# cd openldap-2.2.17
              [root src]# ./configure --prefix=/usr/local/openldap
              [root openldap]# make install
              [root openldap]#
    cd /usr/local/src/
    wget ftp://ftp.openldap.org/pub/OpenLDAP/openldap-release/openldap-2.2.17.tgz
    tar xvfz openldap-2.2.17.tgz
    cd openldap-2.2.17
    ./configure --prefix=/usr/local/openldap --disable-slapd
    make install
    
              
  2. Install ns_ldap. Download and install ns_ldap

    [root aolserver]# cd /usr/local/src/aolserver/
              [root aolserver]# wget http://www.sussdorff.de/resources/nsldap.tgz
              [root aolserver]# tar xfz nsldap.tgz
              [root aolserver]# cd nsldap
              [root ns_pam-0.1]# make install LDAP=/usr/local/openldap INST=/usr/local/aolserver
              [root ns_pam-0.1]#
    cd /usr/local/src/aolserver/
    wget http://www.sussdorff.de/resources/nsldap.tgz
    tar xfz nsldap.tgz
    cd nsldap
    make install LDAP=/usr/local/openldap INST=/usr/local/aolserver
    
              
  3. Configure ns_ldap for traditional use. Traditionally OpenACS has supported ns_ldap for authentication by storing the OpenACS password in an encrypted field within the LDAP server called "userPassword". Furthermore, a CN field was used for searching for the username, usually userID or something similar. This field is identical to the usernamestored in OpenACS. Therefore, the login will only work if you change login method to make use of the username instead.

    • Change config.tcl. Remove the # in front of ns_param nsldap ${bindir}/nsldap.so to enable the loading of the ns_ldap module.

  4. Configure ns_ldap for use with LDAP bind. LDAP authentication usually is done by trying to bind (aka login) a user with the LDAP server. The password of the user is not stored in any field of the LDAP server, but kept internally. The latest version of ns_ldap supports this method with the ns_ldap bind command. All you have to do to enable this is to configure auth_ldap to make use of the BIND authentication instead. Alternatively you can write a small script on how to calculate the username out of the given input (e.g. if the OpenACS username is malte.fb03.tu, the LDAP request can be translated into "ou=malte,ou=fb03,o=tu" (this example is encoded in auth_ldap and you just have to comment it out to make use of it).