Class: ActionDispatch::SSL

Inherits:
Object
  • Object
show all
Defined in:
lib/action_dispatch/middleware/ssl.rb

Overview

This middleware is added to the stack when ‘config.force_ssl = true`, and is passed the options set in `config.ssl_options`. It does three jobs to enforce secure HTTP requests:

1. TLS redirect: Permanently redirects http:// requests to https://
   with the same URL host, path, etc. Enabled by default. Set `config.ssl_options`
   to modify the destination URL
   (e.g. `redirect: { host: "secure.widgets.com", port: 8080 }`), or set
   `redirect: false` to disable this feature.

2. Secure cookies: Sets the `secure` flag on cookies to tell browsers they
   mustn't be sent along with http:// requests. Enabled by default. Set
   `config.ssl_options` with `secure_cookies: false` to disable this feature.

3. HTTP Strict Transport Security (HSTS): Tells the browser to remember
   this site as TLS-only and automatically redirect non-TLS requests.
   Enabled by default. Configure `config.ssl_options` with `hsts: false` to disable.

Set ‘config.ssl_options` with `hsts: { … }` to configure HSTS:

* `expires`: How long, in seconds, these settings will stick. The minimum
  required to qualify for browser preload lists is `18.weeks`. Defaults to
  `180.days` (recommended).
* `subdomains`: Set to `true` to tell the browser to apply these settings
  to all subdomains. This protects your cookies from interception by a
  vulnerable site on a subdomain. Defaults to `false`.
* `preload`: Advertise that this site may be included in browsers'
  preloaded HSTS lists. HSTS protects your site on every visit *except the
  first visit* since it hasn't seen your HSTS header yet. To close this
  gap, browser vendors include a baked-in list of HSTS-enabled sites.
  Go to https://hstspreload.appspot.com to submit your site for inclusion.
  Defaults to `false`.

To turn off HSTS, omitting the header is not enough. Browsers will remember the original HSTS directive until it expires. Instead, use the header to tell browsers to expire HSTS immediately. Setting ‘hsts: false` is a shortcut for `hsts: { expires: 0 }`.

Requests can opt-out of redirection with ‘exclude`:

config.ssl_options = { redirect: { exclude: -> request { request.path =~ /healthcheck/ } } }

Constant Summary collapse

HSTS_EXPIRES_IN =

Default to 180 days, the low end for www.ssllabs.com/ssltest/ and greater than the 18-week requirement for browser preload lists.

15552000

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(app, redirect: {}, hsts: {}, secure_cookies: true, **options) ⇒ SSL

Returns a new instance of SSL.



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# File 'lib/action_dispatch/middleware/ssl.rb', line 51

def initialize(app, redirect: {}, hsts: {}, secure_cookies: true, **options)
  @app = app

  if options[:host] || options[:port]
    ActiveSupport::Deprecation.warn <<-end_warning.strip_heredoc
      The `:host` and `:port` options are moving within `:redirect`:
      `config.ssl_options = { redirect: { host: …, port: … } }`.
    end_warning
    @redirect = options.slice(:host, :port)
  else
    @redirect = redirect
  end

  @exclude = @redirect && @redirect[:exclude] || proc { !@redirect }
  @secure_cookies = secure_cookies

  if hsts != true && hsts != false && hsts[:subdomains].nil?
    hsts[:subdomains] = false

    ActiveSupport::Deprecation.warn <<-end_warning.strip_heredoc
      In Rails 5.1, The `:subdomains` option of HSTS config will be treated as true if
      unspecified. Set `config.ssl_options = { hsts: { subdomains: false } }` to opt out
      of this behavior.
    end_warning
  end

  @hsts_header = build_hsts_header(normalize_hsts_options(hsts))
end

Class Method Details

.default_hsts_options ⇒ Object 



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# File 'lib/action_dispatch/middleware/ssl.rb', line 47

def self.default_hsts_options
  { expires: HSTS_EXPIRES_IN, subdomains: false, preload: false }
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/action_dispatch/middleware/ssl.rb', line 80

def call(env)
  request = Request.new env

  if request.ssl?
    @app.call(env).tap do |status, headers, body|
      set_hsts_header! headers
      flag_cookies_as_secure! headers if @secure_cookies
    end
  else
    return redirect_to_https request unless @exclude.call(request)
    @app.call(env)
  end
end