LDAP Authentication Advanced plugin

Kong Enterprise only: This plugin is only available with a Kong Enterprise subscription.

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Add LDAP Bind Authentication with username and password protection. The plugin will check for valid credentials in the Proxy-Authorization and Authorization header (in this order).

Terminology

plugin: a plugin executing actions inside Kong before or after a request has been proxied to the upstream API.
Service: the Kong entity representing an external upstream API or microservice.
Route: the Kong entity representing a way to map downstream requests to upstream services.
upstream service: this refers to your own API/service sitting behind Kong, to which client requests are forwarded.
API: a legacy entity used to represent your upstream services. Deprecated in favor of Services since CE 0.13.0 and EE 0.32.

Configuration

Enabling the plugin on a Service

Configure this plugin on a Service by making the following request:

$ curl -X POST http://kong:8001/services/{service}/plugins \
    --data "name=ldap-auth-advanced" 

{service} is the id or name of the Service that this plugin configuration will target.

Enabling the plugin on a Route

Configure this plugin on a Route with:

$ curl -X POST http://kong:8001/routes/{route}/plugins \
    --data "name=ldap-auth-advanced" 

{route} is the id or name of the Route that this plugin configuration will target.

Enabling the plugin on an API

If you are using an older version of Kong with the legacy API entity (deprecated in favor of Services since CE 0.13.0 and EE 0.32.), you can configure this plugin on top of such an API by making the following request:

$ curl -X POST http://kong:8001/apis/{api}/plugins \
    --data "name=ldap-auth-advanced" 

api: either id or name of the API that this plugin configuration will target.

Global plugins

Using a database, all plugins can be configured using the http://kong:8001/plugins/ endpoint.
Without a database, all plugins can be configured via the plugins: entry on the declarative configuration file.

A plugin which is not associated to any Service, Route or Consumer (or API, if you are using an older version of Kong) is considered "global", and will be run on every request. Read the Plugin Reference and the Plugin Precedence sections for more information.

Parameters

Here's a list of all the parameters which can be used in this plugin's configuration:

form parameter	description
`name`	The name of the plugin to use, in this case `ldap-auth-advanced`
`service.id`	The ID of the Service the plugin targets.
`route.id`	The ID of the Route the plugin targets.
`enabled` default value: `true`	Whether this plugin will be applied.
`api_id`	The id of the API which this plugin will target. Note: The API Entity is deprecated in favor of Services since CE 0.13.0 and EE 0.32.
`config.ldap_host`	Host on which the LDAP server is running
`config.ldap_port`	TCP port where the LDAP server is listening
`config.ldap_password`	The password to the LDAP server
`config.start_tls` default value: `false`	Set it to `true` to issue StartTLS (Transport Layer Security) extended operation over `ldap` connection
`config.ldaps` default value: `false`	Set it to `true` to use `ldaps`, a secure protocol (that can be configured to TLS) to connect to the LDAP server.
`config.base_dn`	Base DN as the starting point for the search; e.g., “dc=example,dc=com”
`config.verify_ldap_host` default value: `false`	Set it to `true` to authenticate LDAP server. The server certificate will be verified according to the CA certificates specified by the `lua_ssl_trusted_certificate` directive.
`config.attribute`	Attribute to be used to search the user; e.g., “cn”
`config.cache_ttl` default value: `60`	Cache expiry time in seconds
`config.timeout` optional default value: `10000`	An optional timeout in milliseconds when waiting for connection with LDAP server
`config.keepalive` optional default value: `10000`	An optional value in milliseconds that defines for how long an idle connection to LDAP server will live before being closed
`config.anonymous` optional	An optional string (consumer uuid) value to use as an “anonymous” consumer if authentication fails. If empty (default), the request will fail with an authentication failure `4xx`. Please note that this value must refer to the Consumer `id` attribute which is internal to Kong, and not its `custom_id`.
`config.header_type` optional default value: `ldap`	An optional string to use as part of the Authorization header. By default, a valid Authorization header looks like this: `Authorization: ldap base64(username:password)`. If `header_type` is set to “basic” then the Authorization header would be `Authorization: basic base64(username:password)`. Note that `header_type` can take any string, not just `"ldap"` and `"basic"`.
`config.consumer_optional` optional default value: `false`	Whether consumer is optional
`config.consumer_by` optional default value: `[ "username", "custom_id" ]`	Whether to authenticate consumer based on `username` and/or `custom_id`
`config.hide_credentials` optional default value: `false`	An optional boolean value telling the plugin to hide the credential to the upstream server. It will be removed by Kong before proxying the request.
`config.bind_dn`	The DN to bind to. Used to perform LDAP search of user. This bind_dn should have permissions to search for the user being authenticated.
`config.group_base_dn` default value: matches `conf.base_dn`	Sets a distinguished name for the entry where LDAP searches for groups begin.
`config.group_name_attribute` default value: matches `conf.attribute`	Sets the attribute holding the name of a group, typically called `name` (in Active Directory) or `cn` (in OpenLDAP).
`config.group_member_attribute` default value: `memberOf`	Sets the attribute holding the members of the LDAP group.

Usage

In order to authenticate the user, client must set credentials in Proxy-Authorization or Authorization header in following format:

credentials := [ldap

LDAP] base64(username:password)

The plugin will validate the user against the LDAP server and cache the credential for future requests for the duration specified in config.cache_ttl.

Upstream Headers

When a client has been authenticated, the plugin will append some headers to the request before proxying it to the upstream service, so that you can identify the consumer in your code:

X-Credential-Username, the username of the Credential (only if the consumer is not the ‘anonymous’ consumer)
X-Anonymous-Consumer, will be set to true when authentication failed, and the ‘anonymous’ consumer was set instead.
X-Consumer-ID, the ID of the ‘anonymous’ consumer on Kong (only if authentication failed and ‘anonymous’ was set)
X-Consumer-Custom-ID, the custom_id of the ‘anonymous’ consumer (only if authentication failed and ‘anonymous’ was set)
X-Consumer-Username, the username of the ‘anonymous’ consumer (only if authentication failed and ‘anonymous’ was set)

LDAP Search and config.bind_dn

LDAP directory searching is performed during the request/plugin lifecycle. It is used to retrieve the fully qualified DN of the user so a bind request can be performed with the user’s given LDAP username and password. The search for the user being authenticated uses the config.bind_dn property. The search uses scope="sub", filter="<config.attribute>=<username>", and base_dn=<config.base_dn>. Here is an example of how it performs the search using the ldapsearch command line utility:

$ ldapsearch -x -h "<config.ldap_host>" -D "<config.bind_dn>" -b 
"<config.attribute>=<username><config.base_dn>" -w "<config.ldap_password>"

About this Plugin
Made by
Categories	Authentication
Bundled with...
Kong Enterprise 1.3-x 0.36-x 0.35-x 0.34-x
Other Versions
0.36-x 0.35-x 0.34-x 0.33-x