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Reorganize CSRF a bit

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1 parent cbcb947 commit 0b2dd7afd9ee1dfe46506f9d745afb0a23e496ba @wycats wycats committed Oct 28, 2009
@@ -5,7 +5,6 @@ class InvalidAuthenticityToken < ActionControllerError #: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 RequestForgeryProtection
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 <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.
+ # 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:
+ # 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>.
#
- # <%= 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 RequestForgeryProtection
# * 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 ClassMethods
# * <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
+ before_filter :verify_authenticity_token, options
end
end
@@ -88,31 +85,24 @@ def protect_from_forgery(options = {})
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
@@ -97,6 +97,10 @@ def content_type
end
end
+ def forgery_whitelisted?
+ method == :get || xhr? || !(!content_type.nil? && content_type.verify_request?)
+ end
+
def media_type
content_type.to_s
end

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