… or why my cookies don’t have secure flag anymore

Several of you may know that Rails provide force_ssl feature. This is a handy option that will tell Rails application to load website as https when someone tries to access it via http.

This baby comes in two forms:

Developer can specify that the entire website is https in config/enviroments/production.rb or config/initializers/...

# config/enviroments/production.rb

MyApp::Application.configure do
  # ...
  config.force_ssl = true
  # ...

… or Developer can tell particular controller to force_ssl

# app/controllers/secret_stuff_controller.rb
class SecretStuffController < ApplicationController

  # ...

Let’s try the config.force_ssl (config for entire application). All web-pages will be enforced to use https (nice). How about cookies ?

Some of you may know that cookies have security options like:

  • when to expire the cookie (Expire option),
  • should the cookie be sent only via HTTP or also other protocols like JavaScript (HttpOnly)
  • wether the cookie should be sent over by http and https connection or just via https connection (Secure option)

If you’re using in your Rails app authentication gem Devise it will take good care when setting session_id cookie on options HttpOnly and when to expire. But Secure option won’t be set.

This is where force_ssl (still the global config one) comes handy. It will not only enforce the http to https redirect, but will enforce session cookie to be secure => not to be sent via non-secure conection.

Cookies after config.force_ssl firebug

Cookies after config.force_ssl webdeveloper tools

Awesome :)

But problem is that I need to have entire app under https and one controller http. So let’s try controller force_ssl:

Cookies using controller force_ssl firebug

Cookies using controller force_ssl webdeveloper tools

Well I guess we need to check the source :(


# rails/railties/lib/rails/application/default_middleware_stack.rb

def build_stack
  # ...

  if config.session_store
    if config.force_ssl && !config.session_options.key?(:secure)
      config.session_options[:secure] = true
    # ...

  # ...

controller force_ssl

# rails/actionpack/lib/action_controller/metal/force_ssl.rb

# ...
module ForceSsl
  # ...
  def force_ssl(options = {})
    action_options = options.slice(*ACTION_OPTIONS)
    redirect_options = options.except(*ACTION_OPTIONS)
    before_action(action_options) do
  # ...
# ...

My reaction at this point can be described like this => http://youtu.be/TOakzl0k6ik

Solution ?

Well the easiest way would be just tell that:

# config/enviraments/production.rb

 config.session_options[:secure] = true

… right ?

Well, this wont work:

  • A/ Rails will ignore this option ( don’t quite know why because I stopped investigationg source code when I realized point B)

  • B/ you are setting secure=true meaning: send the session cookie only if user is on secure connection. This is ok when config.force_ssl is used globaly on a whole application as everything will be under https, but if you forcing https only on some parts of the application you will not know what is the session of a user visiting site (for example you may want to track if public FAQ was visited by a particular user that is still logged in)

So, the solution: two cookies to save the day!

Basically the idea is that you will leave the “unsecure” session cookie alone and you create another “secure” cookie. You evaluate both cookies to check who the “logged in” user is on https sites (protected sites) and you will still be able to use unsecure cookie to track movement on public pages (once again the “secure” cookie won’t be sent on non-https conection).

In other words this will prevent session hijacking as you need both cookies to validate the user, and only unsecure cookie to track user activity on public pages.

It may be the case that you will need to have two user variables in you controller @current_user and @current_user_non_secure but I’ll skip the implementation details as the article is not about this.

Good example how to implement secure cookie is here:


# app/controllers/sessions_controller.rb

  def create
    # ...
    cookies.signed[:secure_user_id] = {secure: true, value:
    # ...

  def destroy
    # ...

Devise solution

There is devise_ssl_session_verifiable doing exactly what you need.

# Gemfile

# ...
gem 'devise'
gem 'devise_ssl_session_verifiable'
# ...