LDAP Authentication plugin

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

Note: The functionality of this plugin as bundled with versions of IAM prior to 0.14.1 and IAM prior to 0.34 differs from what is documented herein. Refer to the CHANGELOG for details.

Terminology

plugin: a plugin executing actions inside IAM before or after a request has been proxied to the upstream API.
Service: the IAM entity representing an external upstream API or microservice.
Route: the IAM entity representing a way to map downstream requests to upstream services.
upstream service: this refers to your own API/service sitting behind IAM, to which client requests are forwarded.

Configuration

This plugin is compatible with requests with the following protocols:

http
https

This plugin is compatible with DB-less mode.

Enabling the plugin on a Route

With a database

Configure this plugin on a Route with:

$ curl -X POST http://localhost:8001/routes/{route}/plugins \
    --data "name=ldap-auth"  \
    --data "config.hide_credentials=true" \
    --data "config.ldap_host=ldap.example.com" \
    --data "config.ldap_port=389" \
    --data "config.start_tls=false" \
    --data "config.base_dn=dc=example,dc=com" \
    --data "config.verify_ldap_host=false" \
    --data "config.attribute=cn" \
    --data "config.cache_ttl=60" \
    --data "config.header_type=ldap"

Without a database

Configure this plugin on a Route by adding this section do your declarative configuration file:

plugins:
- name: ldap-auth
  route: {route}
  config: 
    hide_credentials: true
    ldap_host: ldap.example.com
    ldap_port: 389
    start_tls: false
    base_dn: dc=example,dc=com
    verify_ldap_host: false
    attribute: cn
    cache_ttl: 60
    header_type: ldap

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

Global plugins

Using a database, all plugins can be configured using the http://localhost: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 IAM) 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`
`route_id`	The id of the Route which this plugin will target.
`enabled` default value: `true`	Whether this plugin will be applied.
`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 IAM before proxying the request.
`config.ldap_host`	Host on which the LDAP server is running.
`config.ldap_port`	TCP port where the LDAP server is listening.
`config.start_tls` default value: `false`	Set it to `true` to issue StartTLS (Transport Layer Security) extended operation over `ldap` connection.
`config.base_dn`	Base DN as the starting point for the search.
`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.
`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: `60000`	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 IAM, 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"`.

Note: The config.header_type option was introduced in IAM 0.12.0. Previous versions of this plugin behave as if ldap was set for this value.

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 IAM (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)