diff options
Diffstat (limited to 'actionpack/lib/action_controller/old_base/request_forgery_protection.rb')
| -rw-r--r-- | actionpack/lib/action_controller/old_base/request_forgery_protection.rb | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/old_base/request_forgery_protection.rb b/actionpack/lib/action_controller/old_base/request_forgery_protection.rb new file mode 100644 index 0000000000..a470c8eec1 --- /dev/null +++ b/actionpack/lib/action_controller/old_base/request_forgery_protection.rb @@ -0,0 +1,123 @@ +module ActionController #:nodoc: + class InvalidAuthenticityToken < ActionControllerError #:nodoc: + end + + module RequestForgeryProtection + extend ActiveSupport::Concern + + # TODO : Remove the defined? check when new base is the main base + if defined?(ActionController::Http) + include AbstractController::Helpers, Session + end + + included do + if defined?(ActionController::Http) + # Sets the token parameter name for RequestForgery. Calling +protect_from_forgery+ + # sets it to <tt>:authenticity_token</tt> by default. + cattr_accessor :request_forgery_protection_token + + # Controls whether request forgergy protection is turned on or not. Turned off by default only in test mode. + class_inheritable_accessor :allow_forgery_protection + self.allow_forgery_protection = true + end + + helper_method :form_authenticity_token + helper_method :protect_against_forgery? + end + + # Protecting controller actions from CSRF attacks by ensuring that all forms are coming from the current web application, not a + # forged link from another site, is done by embedding a token based on a random string stored in the session (which an attacker wouldn't know) in all + # forms and Ajax requests generated by Rails and then verifying the authenticity of that token in the controller. Only + # HTML/JavaScript requests are checked, so this will not protect your XML API (presumably you'll have a different authentication + # scheme there anyway). Also, GET requests are not protected as these should be idempotent anyway. + # + # This is turned on with the <tt>protect_from_forgery</tt> method, which will check the token and raise an + # ActionController::InvalidAuthenticityToken if it doesn't match what was expected. You can customize the error message in + # production by editing public/422.html. A call to this method in ApplicationController is generated by default in post-Rails 2.0 + # applications. + # + # The token parameter is named <tt>authenticity_token</tt> by default. If you are generating an HTML form manually (without the + # use of Rails' <tt>form_for</tt>, <tt>form_tag</tt> or other helpers), you have to include a hidden field named like that and + # set its value to what is returned by <tt>form_authenticity_token</tt>. Same applies to manually constructed Ajax requests. To + # make the token available through a global variable to scripts on a certain page, you could add something like this to a view: + # + # <%= javascript_tag "window._token = '#{form_authenticity_token}'" %> + # + # Request forgery protection is disabled by default in test environment. If you are upgrading from Rails 1.x, add this to + # config/environments/test.rb: + # + # # Disable request forgery protection in test environment + # config.action_controller.allow_forgery_protection = false + # + # == Learn more about CSRF (Cross-Site Request Forgery) attacks + # + # Here are some resources: + # * http://isc.sans.org/diary.html?storyid=1750 + # * http://en.wikipedia.org/wiki/Cross-site_request_forgery + # + # Keep in mind, this is NOT a silver-bullet, plug 'n' play, warm security blanket for your rails application. + # There are a few guidelines you should follow: + # + # * Keep your GET requests safe and idempotent. More reading material: + # * http://www.xml.com/pub/a/2002/04/24/deviant.html + # * http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.1 + # * Make sure the session cookies that Rails creates are non-persistent. Check in Firefox and look for "Expires: at end of session" + # + module ClassMethods + # Turn on request forgery protection. Bear in mind that only non-GET, HTML/JavaScript requests are checked. + # + # Example: + # + # class FooController < ApplicationController + # protect_from_forgery :except => :index + # + # # you can disable csrf protection on controller-by-controller basis: + # skip_before_filter :verify_authenticity_token + # end + # + # Valid Options: + # + # * <tt>:only/:except</tt> - Passed to the <tt>before_filter</tt> call. Set which actions are verified. + def protect_from_forgery(options = {}) + self.request_forgery_protection_token ||= :authenticity_token + before_filter :verify_authenticity_token, :only => options.delete(:only), :except => options.delete(:except) + if options[:secret] || options[:digest] + ActiveSupport::Deprecation.warn("protect_from_forgery only takes :only and :except options now. :digest and :secret have no effect", caller) + end + end + end + + protected + # The actual before_filter that is used. Modify this to change how you handle unverified requests. + def verify_authenticity_token + verified_request? || raise(ActionController::InvalidAuthenticityToken) + end + + # Returns true or false if a request is verified. Checks: + # + # * is the format restricted? By default, only HTML requests are checked. + # * is it a GET request? Gets should be safe and idempotent + # * Does the form_authenticity_token match the given token value from the params? + def verified_request? + !protect_against_forgery? || + request.method == :get || + request.xhr? || + !verifiable_request_format? || + form_authenticity_token == params[request_forgery_protection_token] + end + + def verifiable_request_format? + !request.content_type.nil? && request.content_type.verify_request? + end + + # Sets the token value for the current session. Pass a <tt>:secret</tt> option + # in +protect_from_forgery+ to add a custom salt to the hash. + def form_authenticity_token + session[:_csrf_token] ||= ActiveSupport::SecureRandom.base64(32) + end + + def protect_against_forgery? + allow_forgery_protection && request_forgery_protection_token + end + end +end |