Move remote_ip to a middleware:

* ActionController::Base.ip_spoofing_check deprecated => config.action_dispatch.ip_spoofing_check
  * ActionController::Base.trusted_proxies deprecated => config.action_dispatch.trusted_proxies

actionpack/lib/action_dispatch.rb

@@ -42,13 +42,13 @@ module ActionDispatch
   end
 
   autoload_under 'middleware' do
-    autoload :BlockUntrustedIps
     autoload :Callbacks
     autoload :Cascade
     autoload :Cookies
     autoload :Flash
     autoload :Head
     autoload :ParamsParser
+    autoload :RemoteIp
     autoload :Rescue
     autoload :ShowExceptions
     autoload :Static

actionpack/lib/action_dispatch/http/request.rb

@@ -119,36 +119,7 @@ module ActionDispatch
     # delimited list in the case of multiple chained proxies; the last
     # address which is not trusted is the originating IP.
     def remote_ip
-      remote_addr_list = @env['REMOTE_ADDR'] && @env['REMOTE_ADDR'].scan(/[^,\s]+/)
-
-      unless remote_addr_list.blank?
-        not_trusted_addrs = remote_addr_list.reject {|addr| addr =~ TRUSTED_PROXIES || addr =~ ActionController::Base.trusted_proxies}
-        return not_trusted_addrs.first unless not_trusted_addrs.empty?
-      end
-      remote_ips = @env['HTTP_X_FORWARDED_FOR'] && @env['HTTP_X_FORWARDED_FOR'].split(',')
-
-      if @env.include? 'HTTP_CLIENT_IP'
-        if ActionController::Base.ip_spoofing_check && remote_ips && !remote_ips.include?(@env['HTTP_CLIENT_IP'])
-          # We don't know which came from the proxy, and which from the user
-          raise ActionController::ActionControllerError.new <<EOM
-IP spoofing attack?!
-HTTP_CLIENT_IP=#{@env['HTTP_CLIENT_IP'].inspect}
-HTTP_X_FORWARDED_FOR=#{@env['HTTP_X_FORWARDED_FOR'].inspect}
-EOM
-        end
-
-        return @env['HTTP_CLIENT_IP']
-      end
-
-      if remote_ips
-        while remote_ips.size > 1 && (TRUSTED_PROXIES =~ remote_ips.last.strip || ActionController::Base.trusted_proxies =~ remote_ips.last.strip)
-          remote_ips.pop
-        end
-
-        return remote_ips.last.strip
-      end
-
-      @env['REMOTE_ADDR']
+      (@env["action_dispatch.remote_ip"] || ip).to_s
     end
 
     # Returns the lowercase name of the HTTP server software.

actionpack/lib/action_dispatch/middleware/block_untrusted_ips.rb

@@ -1,25 +0,0 @@
-module ActionDispatch
-  class BlockUntrustedIps
-    class SpoofAttackError < StandardError ; end
-
-    def initialize(app)
-      @app = app
-    end
-
-    def call(env)
-      if @env['HTTP_X_FORWARDED_FOR'] && @env['HTTP_CLIENT_IP']
-        remote_ips = @env['HTTP_X_FORWARDED_FOR'].split(',')
-
-        unless remote_ips.include?(@env['HTTP_CLIENT_IP'])
-          http_client_ip     = @env['HTTP_CLIENT_IP'].inspect
-          http_forwarded_for = @env['HTTP_X_FORWARDED_FOR'].inspect
-
-          raise SpoofAttackError, "IP spoofing attack?!\n  " \
-            "HTTP_CLIENT_IP=#{http_client_ip}\n  HTTP_X_FORWARDED_FOR=http_forwarded_for"
-        end
-      end
-
-      @app.call(env)
-    end
-  end
-end

actionpack/lib/action_dispatch/middleware/remote_ip.rb

@@ -0,0 +1,51 @@
+module ActionDispatch
+  class RemoteIp
+    class IpSpoofAttackError < StandardError ; end
+
+    class RemoteIpGetter
+      def initialize(env, check_ip_spoofing, trusted_proxies)
+        @env = env
+        @check_ip_spoofing = check_ip_spoofing
+        @trusted_proxies = trusted_proxies
+      end
+
+      def remote_addrs
+        @remote_addrs ||= begin
+          list = @env['REMOTE_ADDR'] ? @env['REMOTE_ADDR'].split(/[,\s]+/) : []
+          list.reject { |addr| addr =~ @trusted_proxies }
+        end
+      end
+
+      def to_s
+        return remote_addrs.first if remote_addrs.any?
+
+        forwarded_ips = @env['HTTP_X_FORWARDED_FOR'] ? @env['HTTP_X_FORWARDED_FOR'].strip.split(/[,\s]+/) : []
+
+        if client_ip = @env['HTTP_CLIENT_IP']
+          if @check_ip_spoofing && !forwarded_ips.include?(client_ip)
+            # We don't know which came from the proxy, and which from the user
+            raise IpSpoofAttackError, "IP spoofing attack?!" \
+              "HTTP_CLIENT_IP=#{@env['HTTP_CLIENT_IP'].inspect}" \
+              "HTTP_X_FORWARDED_FOR=#{@env['HTTP_X_FORWARDED_FOR'].inspect}"
+          end
+          return client_ip
+        end
+
+        return forwarded_ips.reject { |ip| ip =~ @trusted_proxies }.last || @env["REMOTE_ADDR"]
+      end
+    end
+
+    def initialize(app, check_ip_spoofing = true, trusted_proxies = nil)
+      @app = app
+      @check_ip_spoofing = check_ip_spoofing
+      regex = '(^127\.0\.0\.1$|^(10|172\.(1[6-9]|2[0-9]|30|31)|192\.168)\.)'
+      regex << "|(#{trusted_proxies})" if trusted_proxies
+      @trusted_proxies = Regexp.new(regex, "i")
+    end
+
+    def call(env)
+      env["action_dispatch.remote_ip"] = RemoteIpGetter.new(env, @check_ip_spoofing, @trusted_proxies)
+      @app.call(env)
+    end
+  end
+end

actionpack/lib/action_dispatch/railtie.rb

@@ -6,6 +6,7 @@ module ActionDispatch
     railtie_name :action_dispatch
 
     config.action_dispatch.x_sendfile_header = "X-Sendfile"
+    config.action_dispatch.ip_spoofing_check = true
 
     # Prepare dispatcher callbacks and run 'prepare' callbacks
     initializer "action_dispatch.prepare_dispatcher" do |app|

actionpack/test/dispatch/request_test.rb

@@ -42,7 +42,7 @@ class RequestTest < ActiveSupport::TestCase
 
     request = stub_request 'HTTP_X_FORWARDED_FOR' => '1.1.1.1',
                            'HTTP_CLIENT_IP'       => '2.2.2.2'
-    e = assert_raise(ActionController::ActionControllerError) {
+    e = assert_raise(ActionDispatch::RemoteIp::IpSpoofAttackError) {
       request.remote_ip
     }
     assert_match /IP spoofing attack/, e.message
@@ -54,18 +54,17 @@ class RequestTest < ActiveSupport::TestCase
     # example is WAP.  Since the cellular network is not IP based, it's a
     # leap of faith to assume that their proxies are ever going to set the
     # HTTP_CLIENT_IP/HTTP_X_FORWARDED_FOR headers properly.
-    ActionController::Base.ip_spoofing_check = false
     request = stub_request 'HTTP_X_FORWARDED_FOR' => '1.1.1.1',
-                           'HTTP_CLIENT_IP'       => '2.2.2.2'
+                           'HTTP_CLIENT_IP'       => '2.2.2.2',
+                           :ip_spoofing_check => false
     assert_equal '2.2.2.2', request.remote_ip
-    ActionController::Base.ip_spoofing_check = true
 
     request = stub_request 'HTTP_X_FORWARDED_FOR' => '8.8.8.8, 9.9.9.9'
     assert_equal '9.9.9.9', request.remote_ip
   end
 
   test "remote ip with user specified trusted proxies" do
-    ActionController::Base.trusted_proxies = /^67\.205\.106\.73$/i
+    @trusted_proxies = /^67\.205\.106\.73$/i
 
     request = stub_request 'REMOTE_ADDR' => '67.205.106.73',
                            'HTTP_X_FORWARDED_FOR' => '3.4.5.6'
@@ -429,6 +428,9 @@ class RequestTest < ActiveSupport::TestCase
 protected
 
   def stub_request(env = {})
+    ip_spoofing_check = env.key?(:ip_spoofing_check) ? env.delete(:ip_spoofing_check) : true
+    ip_app = ActionDispatch::RemoteIp.new(Proc.new { }, ip_spoofing_check, @trusted_proxies)
+    ip_app.call(env)
     ActionDispatch::Request.new(env)
   end
 

railties/lib/rails/configuration.rb

@@ -84,11 +84,12 @@ module Rails
           middleware.use('::Rack::Runtime')
           middleware.use('::Rails::Rack::Logger')
           middleware.use('::ActionDispatch::ShowExceptions', lambda { consider_all_requests_local })
+          middleware.use("::ActionDispatch::RemoteIp", lambda { action_dispatch.ip_spoofing_check }, lambda { action_dispatch.trusted_proxies })
           middleware.use('::Rack::Sendfile', lambda { action_dispatch.x_sendfile_header })
           middleware.use('::ActionDispatch::Callbacks', lambda { !cache_classes })
           middleware.use('::ActionDispatch::Cookies')
-          middleware.use(lambda { ActionController::Base.session_store }, lambda { ActionController::Base.session_options })
-          middleware.use('::ActionDispatch::Flash', :if => lambda { ActionController::Base.session_store })
+          middleware.use(lambda { action_controller.session_store }, lambda { action_controller.session_options })
+          middleware.use('::ActionDispatch::Flash', :if => lambda { action_controller.session_store })
           middleware.use(lambda { metal_loader.build_middleware(metals) }, :if => lambda { metal_loader.metals.any? })
           middleware.use('ActionDispatch::ParamsParser')
           middleware.use('::Rack::MethodOverride')

railties/lib/rails/log_subscriber.rb

@@ -87,6 +87,7 @@ module Rails
     %w(info debug warn error fatal unknown).each do |level|
       class_eval <<-METHOD, __FILE__, __LINE__ + 1
         def #{level}(*args, &block)
+          return unless logger
           logger.#{level}(*args, &block)
         end
       METHOD

railties/test/application/middleware_stack_defaults_test.rb

@@ -0,0 +1,53 @@
+require 'isolation/abstract_unit'
+
+class MiddlewareStackDefaultsTest < Test::Unit::TestCase
+  include ActiveSupport::Testing::Isolation
+
+  def setup
+    boot_rails
+    require "rails"
+    require "action_controller/railtie"
+
+    Object.const_set(:MyApplication, Class.new(Rails::Application))
+    MyApplication.class_eval do
+      config.action_controller.session = { :key => "_myapp_session", :secret => "OMG A SEKRET" * 10 }
+    end
+  end
+
+  def remote_ip(env = {})
+    remote_ip = nil
+    env = Rack::MockRequest.env_for("/").merge(env).merge('action_dispatch.show_exceptions' => false)
+
+    endpoint = Proc.new do |e|
+      remote_ip = ActionDispatch::Request.new(e).remote_ip
+      [200, {}, ["Hello"]]
+    end
+
+    out = MyApplication.middleware.build(endpoint).call(env)
+    remote_ip
+  end
+
+  test "remote_ip works" do
+    assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1")
+  end
+
+  test "checks IP spoofing by default" do
+    assert_raises(ActionDispatch::RemoteIp::IpSpoofAttackError) do
+      remote_ip("HTTP_X_FORWARDED_FOR" => "1.1.1.1", "HTTP_CLIENT_IP" => "1.1.1.2")
+    end
+  end
+
+  test "can disable IP spoofing check" do
+    MyApplication.config.action_dispatch.ip_spoofing_check = false
+
+    assert_nothing_raised(ActionDispatch::RemoteIp::IpSpoofAttackError) do
+      assert_equal "1.1.1.2", remote_ip("HTTP_X_FORWARDED_FOR" => "1.1.1.1", "HTTP_CLIENT_IP" => "1.1.1.2")
+    end
+  end
+
+  test "the user can set trusted proxies" do
+    MyApplication.config.action_dispatch.trusted_proxies = /^4\.2\.42\.42$/
+
+    assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "4.2.42.42,1.1.1.1")
+  end
+end