From 0b2dd7afd9ee1dfe46506f9d745afb0a23e496ba Mon Sep 17 00:00:00 2001 From: Yehuda Katz Date: Wed, 28 Oct 2009 00:12:35 -0700 Subject: Reorganize CSRF a bit --- .../metal/request_forgery_protection.rb | 56 +++++++++------------- actionpack/lib/action_dispatch/http/request.rb | 4 ++ 2 files changed, 27 insertions(+), 33 deletions(-) (limited to 'actionpack') diff --git a/actionpack/lib/action_controller/metal/request_forgery_protection.rb b/actionpack/lib/action_controller/metal/request_forgery_protection.rb index ad06657f86..113c20a758 100644 --- a/actionpack/lib/action_controller/metal/request_forgery_protection.rb +++ b/actionpack/lib/action_controller/metal/request_forgery_protection.rb @@ -5,7 +5,6 @@ module ActionController #:nodoc: module RequestForgeryProtection extend ActiveSupport::Concern - # TODO : Remove the defined? check when new base is the main base include AbstractController::Helpers, Session included do @@ -21,26 +20,26 @@ module ActionController #:nodoc: 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. + # 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 protect_from_forgery 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. + # 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 authenticity_token by default. If you are generating an HTML form manually (without the - # use of Rails' form_for, form_tag or other helpers), you have to include a hidden field named like that and - # set its value to what is returned by form_authenticity_token. 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: + # The token parameter is named authenticity_token by default. If you are generating an HTML form + # manually (without the use of Rails' form_for, form_tag or other helpers), you have to + # include a hidden field named like that and set its value to what is returned by + # form_authenticity_token. # - # <%= 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: + # 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 @@ -57,7 +56,8 @@ module ActionController #:nodoc: # * 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" + # * 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. @@ -76,10 +76,7 @@ module ActionController #:nodoc: # * :only/:except - Passed to the before_filter 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 + before_filter :verify_authenticity_token, options end end @@ -88,31 +85,24 @@ module ActionController #:nodoc: 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? || + !protect_against_forgery? || request.forgery_whitelisted? || 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. def form_authenticity_token session[:_csrf_token] ||= ActiveSupport::SecureRandom.base64(32) end def protect_against_forgery? - allow_forgery_protection && request_forgery_protection_token + allow_forgery_protection end end end diff --git a/actionpack/lib/action_dispatch/http/request.rb b/actionpack/lib/action_dispatch/http/request.rb index 1e366520c9..bb99fac5e0 100755 --- a/actionpack/lib/action_dispatch/http/request.rb +++ b/actionpack/lib/action_dispatch/http/request.rb @@ -97,6 +97,10 @@ module ActionDispatch end end + def forgery_whitelisted? + method == :get || xhr? || !(!content_type.nil? && content_type.verify_request?) + end + def media_type content_type.to_s end -- cgit v1.2.3