Mail-in-a-Box LDAP

This is a version of Mail-in-a-Box with LDAP used as the user account database instead of sqlite.

It allows use of a remote Nextcloud that authenticate users against Mail-in-a-Box using Nextcloud's official LDAP support. A single user account database shared with Nextcloud was originally the goal of the project which would simplify deploying a private mail and cloud service for a home or small business.

To add a new account to Nextcloud, simply add a new email account with MiaB-LDAP's management web interface. Quotas and other account settings are made within Nextcloud.

Also see companion project Cloud-in-a-Box

Additional features above what Mail-in-a-Box (upstream) provides:

1. Encryption-at-rest of user-data using a LUKS partition (optional)
2. Log capture daemon and graphical UI for reporting on system activity
3. Display names for users (not just a user id), and comments for aliases to better keep track of what their intended use is
4. Ability to modify/update Postgrey's whitelist from the management console

Upstream changes are merged as they become available, and releases are numbered the same as upstream.

How to connect to a remote Nextcloud

To integrate Mail-in-a-Box w/LDAP (MiaB-LDAP) with Nextcloud, changes must be made on both sides. These changes are mostly automated, you'll just need to copy a couple of files.

On MiaB-LDAP

1. Enable the remote-nextcloud mod, then run setup.

To enable the mod, create the directory local in the directory where mailinabox is installed (usually $HOME/mailinabox), then create a symbolic link to setup/mods.available/remote-nextcloud.sh. e.g. run this command from the mailinabox directory:

mkdir -p local; ln -s ../setup/mods.available/remote-nextcloud.sh local/remote-nextcloud.sh

Re-run setup, by executing setup/start.sh (or ehdd/start-encrypted.sh if using encryption-at-rest) as root. During setup you will be prompted for the hostname and web prefix of your remote Nextcloud box.

Once enabled, you'll find that Roundcube and Z-Push (ActiveSync) will use the remote Nextcloud for contacts and calendar instead of the local Nextcloud, which will be disabled. If you upgraded, old contacts will still be available in Roundcube, but will be read-only. Users can drag them into the remote Nextcloud from Roundcube.

On the remote Nextcloud

2. Hook Nextcloud to MiaB-LDAP by running connect-nextcloud-to-miab.sh

Copy the file setup/mods.available/connect-nextcloud-to-miab.sh to the Nextcloud box and run it as root (if you installed Cloud-in-a-Box, this script is already available in the setup directory). This will configure Nextcloud's "LDAP user and group backend" with the MiaB-LDAP details and ensure the contacts and calendar apps are installed. This does not replace or alter your ability to log into Nextcloud with any existing local Nextcloud accounts. It only allows MiaB-LDAP users to log into Nextcloud using their MiaB-LDAP credentials.

Under-the-Hood

Additional directory in user-data

A new ldap directory is created by setup under STORAGE_ROOT (/home/user-data/ldap) that holds the LDAP database, so that it gets backed up by the normal backup process. In there, you will also find all LDAP service account credentials created by setup in /home/user-data/ldap/miab_ldap.conf, such as those for Nextcloud. Service accounts have limited rights to make changes and should be preferred over the use of the LDAP admin account.

LDAP schema for postfix and dovecot

See conf/postfix.schema and conf/mta-totp.schema for more details on the LDAP schema.

LDAP logs

LDAP server logs are stored in /var/log/ldap/slapd.log and rotated daily.

Command line queries

To perform general command-line searches against your LDAP database, run setup/ldap -search "\<query\>" as root, where query can be a distinguished name to show all attributes of that dn, or an LDAP search enclosed in parenthesis. Some examples:

• setup/ldap.sh -search "(mail=alice@mydomain.com)" (show alice)
• setup/ldap.sh -search "(|(mail=alice.*)(mail=bruce.*))" (show all alices and bruces)
• setup/ldap.sh -search "(objectClass=mailuser)" (show all users)
• etc.

This is a convenient way to run ldapsearch having all the correct command line arguments, but any LDAP tool will also work.

Direct LDAP database manipulation is not recommended for things like adding users or groups using ldapmodify or other LDAP database tools. Instead, use the MiaB admin interface or REST API. Adding or removing a user or group with the admin interface will trigger additional database and system changes by the management daemon, such as updating DNS zones for new email domains, updating group memberships, etc, that would not be performed with a direct change.

Migration

Running any of the setup scripts to install MiaB-LDAP (miab, setup/bootstrap.sh, setup/start.sh, etc) will automatically migrate your current installation from sqlite to LDAP. Ensure you've backed up user-data before running.