12 KiB
| layout | title | parent | grand_parent | nav_order |
|---|---|---|---|---|
| default | LDAP | Authentication Backends | Configuration | 2 |
LDAP
Authelia supports using a LDAP server as the users database.
Configuration
authentication_backend:
disable_reset_password: false
refresh_interval: 5m
ldap:
implementation: custom
url: ldap://127.0.0.1
timeout: 5s
start_tls: false
tls:
server_name: ldap.example.com
skip_verify: false
minimum_version: TLS1.2
base_dn: DC=example,DC=com
username_attribute: uid
additional_users_dn: ou=users
users_filter: (&({username_attribute}={input})(objectClass=person))
additional_groups_dn: ou=groups
groups_filter: (&(member={dn})(objectClass=groupOfNames))
group_name_attribute: cn
mail_attribute: mail
display_name_attribute: displayName
user: CN=admin,DC=example,DC=com
password: password
Options
implementation
Configures the LDAP implementation used by Authelia.
See the Implementation Guide for information.
url
The LDAP URL which consists of a scheme, address, and port. Format is <scheme>://<address>:<port> or
<scheme>://<address> where scheme is either ldap or ldaps.
If utilising an IPv6 literal address it must be enclosed by square brackets:
url: ldap://[fd00:1111:2222:3333::1]
timeout
The timeout for dialing an LDAP connection.
start_tls
Enables use of the LDAP StartTLS process which is not commonly used. You should only configure this if you know you need it. The initial connection will be over plain text, and Authelia will try to upgrade it with the LDAP server. LDAPS URL's are slightly more secure.
tls
Controls the TLS connection validation process. You can see how to configure the tls section here.
base_dn
Sets the base distinguished name container for all LDAP queries. If your LDAP domain is example.com this is usually
dc=example,dc=com, however you can fine tune this to be more specific for example to only include objects inside the
authelia OU: ou=authelia,dc=example,dc=com. This is prefixed with the additional_users_dn for
user searches and additional_groups_dn for groups searches.
username_attribute
The LDAP attribute that maps to the username in Authelia. The default value is dependent on the implementation, refer to the attribute defaults for more information.
additional_users_dn
Additional LDAP path to append to the base_dn when searching for users. Useful if you want to restrict
exactly which OU to get users from for either security or performance reasons. For example setting it to
ou=users,ou=people with a base_dn set to dc=example,dc=com will mean user searches will occur in
ou=users,ou=people,dc=example,dc=com. The default value is dependent on the implementation, refer
to the attribute defaults for more information.
users_filter
The LDAP filter to narrow down which users are valid. This is important to set correctly as to exclude disabled users. The default value is dependent on the implementation, refer to the attribute defaults for more information.
additional_groups_dn
Similar to additional_users_dn but it applies to group searches.
groups_filter
Similar to users_filter but it applies to group searches. In order to include groups the memeber is not a direct member of, but is a member of another group that is a member of those (i.e. recursive groups), you may try using the following filter which is currently only tested against Microsoft Active Directory:
(&(member:1.2.840.113556.1.4.1941:={dn})(objectClass=group)(objectCategory=group))
mail_attribute
The attribute to retrieve which contains the users email addresses. This is important for the device registration and password reset processes. The user must have an email address in order for Authelia to perform identity verification when a user attempts to reset their password or register a second factor device.
display_name_attribute
The attribute to retrieve which is shown on the Web UI to the user when they log in.
user
The distinguished name of the user paired with the password to bind with for lookup and password change operations.
password
The password of the user paired with the user to bind with for lookup and password change operations. Can also be defined using a secret which is the recommended for containerized deployments.
Implementation Guide
There are currently two implementations, custom and activedirectory. The activedirectory implementation
must be used if you wish to allow users to change or reset their password as Active Directory
uses a custom attribute for this, and an input format other implementations do not use. The long term
intention of this is to have logical defaults for various RFC implementations of LDAP.
Filter replacements
Various replacements occur in the user and groups filter. The replacements either occur at startup or upon an LDAP search.
Users filter replacements
| Placeholder | Phase | Replacement |
|---|---|---|
| {username_attribute} | startup | The username attribute configured |
| {mail_attribute} | startup | The mail attribute configured |
| {display_name_attribute} | startup | The display name attribute configured |
| {input} | search | The input into the username field |
Groups filter replacements
| Placeholder | Phase | Replacement |
|---|---|---|
| {input} | search | The input into the username field |
| {username} | search | The username from the profile lookup obtained from the username attribute |
| {dn} | search | The distinguished name from the profile lookup |
Defaults
The below tables describes the current attribute defaults for each implementation.
Attribute defaults
This table describes the attribute defaults for each implementation. i.e. the username_attribute is described by the Username column.
| Implementation | Username | Display Name | Group Name | |
|---|---|---|---|---|
| custom | n/a | displayName | cn | |
| activedirectory | sAMAccountName | displayName | cn |
Filter defaults
The filters are probably the most important part to get correct when setting up LDAP. You want to exclude disabled accounts. The active directory example has two attribute filters that accomplish this as an example (more examples would be appreciated). The userAccountControl filter checks that the account is not disabled and the pwdLastSet makes sure that value is not 0 which means the password requires changing at the next login.
| Implementation | Users Filter | Groups Filter |
|---|---|---|
| custom | n/a | n/a |
| activedirectory | (&(|({username_attribute}={input})({mail_attribute}={input}))(sAMAccountType=805306368)(!(userAccountControl:1.2.840.113556.1.4.803:=2))(!(pwdLastSet=0))) | (&(member={dn})(objectClass=group)(objectCategory=group)) |
Note: The Active Directory filter (sAMAccountType=805306368) is exactly the same as
(&(objectCategory=person)(objectClass=user)) except that the former is more performant, you can read more about this
and other Active Directory filters on the TechNet wiki.
Refresh Interval
This setting takes a duration notation that sets the max frequency for how often Authelia contacts the backend to verify the user still exists and that the groups stored in the session are up to date. This allows us to destroy sessions when the user no longer matches the user_filter, or deny access to resources as they are removed from groups.
In addition to the duration notation, you may provide the value always or disable. Setting to always
is the same as setting it to 0 which will refresh on every request, disable turns the feature off, which is
not recommended. This completely prevents Authelia from refreshing this information, and it would only be
refreshed when the user session gets destroyed by other means like inactivity, session expiration or logging
out and in.
This value can be any value including 0, setting it to 0 would automatically refresh the session on every single request. This means Authelia will have to contact the LDAP backend every time an element on a page loads which could be substantially costly. It's a trade-off between load and security that you should adapt according to your own security policy.
Important notes
Users must be uniquely identified by an attribute, this attribute must obviously contain a single value and be guaranteed by the administrator to be unique. If multiple users have the same value, Authelia will simply fail authenticating the user and display an error message in the logs.
In order to avoid such problems, we highly recommended you follow https://www.ietf.org/rfc/rfc2307.txt by using
sAMAccountName for Active Directory and uid for other implementations as the attribute holding the
unique identifier for your users.
As of versions > 4.24.0 the users_filter must include the username_attribute placeholder, not including this will
result in Authelia throwing an error.
In versions <= 4.24.0 not including the username_attribute placeholder will cause issues with the session refresh
and will result in session resets when the refresh interval has expired, default of 5 minutes.