Redmine LDAP Sync

This redmine plugin extends the ldap authentication with user/group synchronization.

Features:

• Synchronization of user fields and groups on login.
• Detects and disables users that have been removed from LDAP.
• Detects and disables users that have been marked as disabled on Active Directory (see MS KB Article 305144 for details).
• Can detect and include nested groups. Upon login the nested groups are retrieved from disk cache. This cache can only be updated with the rake task.
• A rake task is available for manual or periodic synchronization of groups and users.

Remarks:

• The plugin is prepared and intended to run with any LDAP directory. But, the author can only guarantee it to work correctly with Active Directory and Slapd.
• An user will only be removed from groups that exist on LDAP. This behaviour is intended as it allows both ldap and non-ldap groups to coexist.
• Deleted groups on LDAP will not be deleted on redmine.

Installation & Upgrade

Install/Upgrade

1. install. - Copy your plugin directory into #{RAILS_ROOT}/plugins. If you are downloading the plugin directly from GitHub, you can do so by changing into the #{RAILS_ROOT}/plugins directory and issuing the command:

   git clone git://github.com/thorin/redmine_ldap_sync.git
   

   upgrade - Backup and replace the old plugin directory with the new plugin files. If you are downloading the plugin directly from GitHub, you can do so by changing into the plugin directory and issuing the command git pull.

2. Update the ruby gems by changing into the redmine's directory and run the following command.

   bundle install
   

3. upgrade - Still on the redmine's directory, run the following command to upgrade your database (make a db backup before).

   rake redmine:plugins:migrate RAILS_ENV=production
   

4. Change into redmine's directory #{RAILS_ROOT} and run the following command.

   rake -T redmine:plugins:ldap_sync RAILS_ENV=production
   

   If the installation/upgrade was successful you should now see the list of Rake Tasks.

5. Restart Redmine.

You should now be able to see Redmine LDAP Sync listed among the plugins in Administration -> Plugins.

Uninstall

1. Change into redmine's directory #{RAILS_ROOT} and run the following command to downgrade the database (make a db backup before):

   rake redmine:plugins:migrate NAME=redmine_ldap_sync VERSION=0 RAILS_ENV=production
   

2. Remove the plugin from the plugins folder: #{RAILS_ROOT}/plugins

3. Restart Redmine.

Usage

Configuration

Open Administration > Ldap Synchronization to access the plugin configuration:

LDAP settings:

• Base settings - Preloads the configuration with predefined settings.
• Group base DN - The path to where the groups are located. Eg, ou=people,dc=smokeyjoe,dc=com.
• Groups objectclass - The groups object class.
• Users objectclass - The users object class.
• Users search scope - One level or whole subtree.
  • One level: searches one level below the user base DN, i.e. all its immediate children only.
  • Whole subtree: searches the whole subtree rooted at user base DN.
• Group name pattern - (optional) An RegExp that should match up with the name of the groups that should be imported. Eg, \.team$.
• Group search filter - (optional) An LDAP search filter to be applied whenever search for groups.
• Account disabled test - A ruby boolean expression that should evaluate an account's flags (the variable flags) and return true if the account is disabled. Eg., flags.to_i & 2 != 0 or flags.include? 'D'.
• Group membership - Specifies how to determine the user's group membership. The possible values are:
  • On the group class: membership determined from the list of users contained on the group.
  • On the user class: membership determined from the list of groups contained on the user.
• Enable nested groups - Enables and specifies how to identify the groups nesting. When enabled the plugin will look for the groups' parent groups, and so on, and add those groups to the users. The possible values are:
  • Membership on the parent class: group membership determined from the list of groups contained on the parent group.
  • Membership on the member class: group membership determined from the list of groups contained on the member group.

LDAP attributes:

• Group name (group) - The ldap attribute from where to fetch the group's name. Eg, sAMAccountName.
• Account flags (user) - The ldap attribute containing the account disabled flag. Eg., userAccountControl.
• Primary group (user) - The ldap attribute that identifies the primary group of the user. This attribute will also be used as group id when searching for the group. Eg, gidNumber
• Members (group) - The ldap attribute from where to fetch the group's members. Visible if the group membership is on the group class. Eg, member.
• Memberid (user) - The ldap attribute from where to fetch the user's memberid. This attribute must match with the members attribute. Visible if the group membership is on the group class. Eg, dn.
• Groups (user) - The ldap attribute from where to fetch the user's groups. Visible if the group membership is on the user class. Eg, memberof.
• Groupid (group) - The ldap attribute from where to fetch the group's groupid. This attribute must match with the groups attribute. Visible if the group membership is on the user class. Eg, distinguishedName.
• Member groups (group) - The ldap attribute from where to fetch the group's member groups. Visible if the nested groups membership is on the parent class. Eg, member.
• Memberid attribute (group) - The ldap attribute from where to fetch the member group's memberid. This attribute must match with the member groups attribute. Eg, distinguishedName.
• Parent groups (group) - The ldap attribute from where to fetch the group's parent groups. Visible if the nested groups membership is on the member class. Eg, memberOf.
• Parentid attribute (group) - The ldap attribute from where to fetch the parent group's id. This attribute must match with the parent groups attribute. Eg, distinguishedName.

Synchronization actions:

• Users must be members of - (optional) A group to wich the users must belong to to have access enabled to redmine.
• Administrators group - (optional) All members of this group will become redmine administrators.
• Add users to group - (optional) A group to wich all the users created from this LDAP authentication will added upon creation. This group should not exist on LDAP.
• Create new groups - If enabled, groups that don't already exist on redmine will be created.
• Create new users - If enabled, users that don't already exist on redmine will be created when running the rake task.
• Synchronize on login - Enables/Disables users synchronization on login. The possible values are:
  • User fields and groups: Both the fields and groups will be synchronized on login. If a user is disabled on LDAP or removed from the users must be member of group, the user will be locked and the access denied.
  • User fields: Only the fields will be synchronized on login. If a user is disabled on LDAP, the user will be locked and the access denied. Changes on groups will not lock the user.
  • Disabled: No synchronization is done on login.
• Dynamic groups¹ - Enables/Disables dynamic groups. The possible values are:
  • Enabled: While searching for groups, Ldap Sync will also search for dynamic groups.
  • Enabled with a ttl: The dynamic groups cache² will expire every t minutes.
  • Disabled: Ldap Sync will not search for dynamic groups.
• User/Group fields:
  • Synchronize - If enabled, the selected field will be synchronized both on the rake tasks and after every login.
  • LDAP attribute - The ldap attribute to be used as reference on the synchronization.
  • Default value - Shows the value that will be used as default.

Rake tasks

The following tasks are available:

# rake -T redmine:plugins:ldap_sync
rake redmine:plugins:ldap_sync:sync_all     # Synchronize both redmine's users and groups with LDAP
rake redmine:plugins:ldap_sync:sync_groups  # Synchronize redmine's groups fields with those on LDAP
rake redmine:plugins:ldap_sync:sync_users   # Synchronize redmine's users fields and groups with those on LDAP

This tasks can be used to do periodic synchronization. For example:

# Synchronize users with ldap @ every 60 minutes
35 * * * *   www-data /usr/bin/rake -f /opt/redmine/Rakefile --silent redmine:plugins:ldap_sync:sync_users RAILS_ENV=production 2>&- 1>&-

The tasks recognize three environment variables:

• DRY_RUN - Performs a run without changing the database.
• ACTIVATE_USERS - Activates users if they're active on LDAP.
• LOG_LEVEL - Controls the rake task verbosity. The possible values are:
  • silent: Nothing is written to the output.
  • error: Only errors are written to the output.
  • change: Only writes errors and changes made to the user/group's base.
  • debug: Detailed information about the execution is visible to help identify errors. This is the default value.

Base settings

All the base settings are loaded from the plain YAML file config/base_settings.yml. Please be aware that those settings weren't tested and may not work. Saying so, I'll need your help to make these settings more accurate.

License

This plugin is released under the GPL v3 license. See LICENSE for more information.

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1. For details about dynamic groups see OpenLDAP Overlays - Dynamic Lists or slapo-dynlist(5) - Linux man page.
2. Searching for an user's dynamic groups is an costly task. To easy it up, a cache is used to store the relationship between dynamic groups and users. When running the rake task this cache will be refreshed.