Synapse LDAP Auth Provider

Allows synapse to use LDAP as a password provider.

This allows users to log in to synapse with their username and password from an LDAP server. There is also ma1sd (3rd party) that offers more fully-featured integration.

Warning

Synapse's password provider plugin functionality (which this module relies on) is not compatible with Matrix Authentication Service (MAS), the next-gen Matrix auth server.

To use Synapse and MAS together with an LDAP backend, it is recommended to use Dex with MAS, instead of matrix-synapse-ldap3. See the relevant MAS documentation for information on configuring Dex in MAS.

Installation

• Included as standard in the deb packages and docker images from matrix.org.
• If you installed into a virtualenv:
  • Ensure pip is up-to-date: pip install -U pip.
  • Install the LDAP password provider: pip install matrix-synapse-ldap3.
• For other installation mechanisms, see the documentation provided by the maintainer.

Usage

Example Synapse configuration:

   modules:
    - module: "ldap_auth_provider.LdapAuthProviderModule"
      config:
        enabled: true
        uri: "ldap://ldap.example.com:389"
        start_tls: true
        base: "ou=users,dc=example,dc=com"
        attributes:
           uid: "cn"
           mail: "mail"
           name: "givenName"
        #bind_dn:
        #bind_password:
        #filter: "(objectClass=posixAccount)"
        # Additional options for TLS, can be any key from https://ldap3.readthedocs.io/en/latest/ssltls.html#the-tls-object
        #tls_options:
        #  validate: true
        #  local_certificate_file: foo.crt
        #  local_private_key_file: bar.pem
        #  local_private_key_password: secret

If you would like to specify more than one LDAP server for HA, you can provide uri parameter with a list. Default HA strategy of ldap3.ServerPool is employed, so first available server is used.

   modules:
    - module: "ldap_auth_provider.LdapAuthProviderModule"
      config:
        enabled: true
        uri:
           - "ldap://ldap1.example.com:389"
           - "ldap://ldap2.example.com:389"
        start_tls: true
        base: "ou=users,dc=example,dc=com"
        attributes:
           uid: "cn"
           mail: "email"
           name: "givenName"
        #bind_dn:
        #bind_password:
        #filter: "(objectClass=posixAccount)"
        #tls_options:
        #  validate: true
        #  local_certificate_file: foo.crt
        #  local_private_key_file: bar.pem
        #  local_private_key_password: secret

If you would like to enable login/registration via email, or givenName/email binding upon registration, you need to enable search mode. An example config in search mode is provided below:

   modules:
    - module: "ldap_auth_provider.LdapAuthProviderModule"
      config:
        enabled: true
        mode: "search"
        uri: "ldap://ldap.example.com:389"
        start_tls: true
        base: "ou=users,dc=example,dc=com"
        attributes:
           uid: "cn"
           mail: "mail"
           name: "givenName"
        # Search auth if anonymous search not enabled
        bind_dn: "cn=hacker,ou=svcaccts,dc=example,dc=com"
        bind_password: "ch33kym0nk3y"
        #filter: "(objectClass=posixAccount)"
        #tls_options:
        #  validate: true
        #  local_certificate_file: foo.crt
        #  local_private_key_file: bar.pem
        #  local_private_key_password: secret

Alternatively you can also put the bind_password of your service user into its own file to not leak secrets into your configuration:

   modules:
    - module: "ldap_auth_provider.LdapAuthProviderModule"
      config:
        enabled: true
        # all the other options you need
        bind_password_file: "/var/secrets/synapse-ldap-bind-password"

Please note that every trailing \n in the password file will be stripped automatically.

Active Directory forest support

If the active_directory flag is set to true, an Active Directory forest will be searched for the login details. In this mode, the user enters their login details in one of the forms:

• <login>/<domain>
• <domain>\<login>

In either case, this will be mapped to the Matrix UID <login>/<domain> (The normal AD domain separators, @ and \, cannot be used in Matrix User Identifiers, so / is used instead.)

Let's say you have several domains in the example.com forest:

   modules:
    - module: "ldap_auth_provider.LdapAuthProviderModule"
      config:
        enabled: true
        mode: "search"
        uri: "ldap://main.example.com:389"
        base: "dc=example,dc=com"
        # Must be true for this feature to work
        active_directory: true
        # Optional. Users from this domain may log in without specifying the domain part
        default_domain: main.example.com
        attributes:
           uid: "userPrincipalName"
           mail: "mail"
           name: "givenName"
        bind_dn: "cn=hacker,ou=svcaccts,dc=example,dc=com"
        bind_password: "ch33kym0nk3y"

With this configuration the user can log in with either main\someuser, main.example.com\someuser, someuser/main.example.com or someuser.

Users of other domains in the example.com forest can log in with domain\login or login/domain.

Please note that userPrincipalName or a similar-looking LDAP attribute in the format login@domain must be used when the active_directory option is enabled.

Troubleshooting and Debugging

matrix-synapse-ldap3 logging is included in the Synapse homeserver log (typically homeserver.log). The LDAP plugin log level can be increased to DEBUG for troubleshooting and debugging by making the following modifications to your Synapse server's logging configuration file:

• Set the value for handlers.file.level to DEBUG:

   handlers:
     file:
       # [...]
       level: DEBUG

• Add the following to the loggers section:

   loggers:
      # [...]
      ldap3:
        level: DEBUG
      ldap_auth_provider:
        level: DEBUG

Finally, restart your Synapse server for the changes to take effect:

synctl restart