+++ /dev/null
-module ActionController #:nodoc:
- class InvalidAuthenticityToken < ActionControllerError #:nodoc:
- end
-
- module RequestForgeryProtection
- def self.included(base)
- base.class_eval do
- helper_method :form_authenticity_token
- helper_method :protect_against_forgery?
- end
- base.extend(ClassMethods)
- 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 and AJAX 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 ||
- !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
projects / feedcatcher.git / blobdiff