trauth

🔑 A simple, cookie based Traefik middleware plugin for HTTP Basic Single Sign-on

trauth reads htpasswd formatted data as a credentials database, prompting via HTTP basic auth. Once authenticated, a (configurable) cookie will be set such that any other services sharing that domain will also be authenticated.

Note: This plugin changed significantly in the version 1.4.x release from a ForwardAuth server to a middleware plugin. If you are interested in the ForwardAuth server then checkout the old branch.

usage

As this is a middleware plugin, you need to do two things. Install the plugin and then configure the middleware.

installation

A static configuration is needed. Either add it to your existing traefik.yml like this:

experimental:
  plugins:
    trauth:
      moduleName: github.com/leonjza/trauth
      version: v1.5.0 # or whatever the latest version is

Or, add it as labels to your docker-compose.yml (or similar).

services:
  traefik:
    image: traefik
    command:
      - --experimental.plugins.trauth.moduleName=github.com/leonjza/trauth
      - --experimental.plugins.trauth.version=v1.5.0

configuration

As this plugin is middleware, you need to both attach the middleware to an appropriate http.router, as well as configure the middleware itself. Configuration will depend on how you use Traefik, but here are some examples.

The available configuration options are as follows:

Option	Required	Default Value	Notes
`domain`	True		The domain name the authentication cookie will be scoped to.
`realm`	False	`Restricted`	A message to display when prompting for credentials. Note, not all browsers show this to users anymore.
`cookiename`	False	`trauth`	A message to display when prompting for credentials. Note, not all browsers show this to users anymore.
`cookiepath`	False	`/`	The name of the cookie to use for authentication.
`cookiekey`	False	generated	The authentication key used to check cookie authenticity. Note See cookiekey section below
`cookieksecure`	False	`false`	Use the `secure` flag when setting the authentication cookie.
`cookiekhttponly`	False	`false`	Use the `httponly` flag when setting the authentication cookie.
`users`	False if `usersfile` is set		A htpasswd formatted list of users to accept authentication for. If `usersfile` is not set, then this value must be set.
`usersfile`	False if `users` is set		A path to a htpasswd formatted file with a list of users to accept authentication for. If `users` is not set, then this value must be set.
`rules`	False		A rules object that defines hostnames and paths where authentication requirements are skipped

cookiekey

By default, trauth will generate a new, random value for cookiekey if one is not explicitly set, or is set to a value that is not 32 asci characters long. In many cases, this is ok, however, special consideration should be given to cases where this plugin is used in multiple places. By setting a static cookiekey, you garuantee that cookies across instances of the plugin can read the values within. If each instance of the plugin (where multiple instances will spawn if there are multiple unique definititions of the middleware) generated their own key, none will accept the cookie value set by another.

For an example, have a look a the docker-compose.yml file in this repository.

rules

Rules are optional and useful if you have web services that should be authenticated by default, but some parts of the service should be available without authentication (or at least, not blocked by this middleware as it may have its own authentication you want to use instead). For example, say a web application exposes an API, and you want to have that API (or parts of it), available externally.

Rules have two configuration options. A domain, and a regular expression defining the resource (or URL path) to exclude.

For an example, have a look a the docker-compose.yml file in this repository.

configuration examples

As dynamic configuration:

http:
  routers:
    myservice:
      middlewares:
        - sso
    
  middlewares:
    sso:
      plugin:
        trauth:
          domain: mydomain.local
          cookiname: sso-cookie
          users: admin:$$2y$$05$$fVvJElbTaB/Cw9FevNc2keGo6sMRhY2e55..U.6zOsca3rQuuAU1e
          rules:
          - domain: service.mydomain.local
            excludes:
            - ^/api/v1/.*$
            - ^/api/v2/.*$

As labels:

traefik.http.routers.myservice.middlewares: sso
traefik.http.middlewares.sso.plugin.trauth.domain: mydomain.local
traefik.http.middlewares.sso.plugin.trauth.cookiename: sso-cookie
# optional rules
traefik.http.middlewares.sso.plugin.trauth.rules[0].domain: service.mydomain.local
traefik.http.middlewares.sso.plugin.trauth.rules[0].excludes[0].exclude: ^/api/v1/.*$
traefik.http.middlewares.sso.plugin.trauth.rules[0].excludes[1].exclude: ^/api/v2/.*$
# *note* the double $$ here to escape a single $
traefik.http.middlewares.sso.plugin.trauth.users: admin:$$2y$$05$$fVvJElbTaB/Cw9FevNc2keGo6sMRhY2e55..U.6zOsca3rQuuAU1e

For more a more complete example, check out the docker-compose.yml file in this repo.

development

An example docker-compose.dev.yml is included to show how to get this plugin up and running. No binary releases are nessesary as the stack is configured to mount this source repository in the appropriate location.

adding users

trauth uses a basic Apache htpasswd file format. For detailed usage of htpasswd, please see this guide.

Users can be specified using either ther users or usersfile configuration options. In both cases, the same format is needed. For the users option, the content of a well formatted htpasswd file can be pasted as the value of the key. For usersfile, the location of a file generated using the steps that follow need to be set.

To add a new user in a new htpass file, using the Bcrypt hashing algorithm, run:

htpasswd -Bc htpass username1

To add a new user to an existing htpass file, run:

htpasswd -B htpass username2

eniac888 / trauth