1 files changed, 80 insertions, 0 deletions
diff --git a/railties/test/application/middleware/remote_ip_test.rb b/railties/test/application/middleware/remote_ip_test.rb
new file mode 100644
index 0000000000..83cf8a27f7
--- /dev/null
+++ b/railties/test/application/middleware/remote_ip_test.rb
@@ -0,0 +1,80 @@
+# frozen_string_literal: true
+
+require "ipaddr"
+require "isolation/abstract_unit"
+require "active_support/key_generator"
+
+module ApplicationTests
+  class RemoteIpTest < ActiveSupport::TestCase
+    include ActiveSupport::Testing::Isolation
+
+    def remote_ip(env = {})
+      remote_ip = nil
+      env = Rack::MockRequest.env_for("/").merge(env).merge!(
+        "action_dispatch.show_exceptions" => false,
+        "action_dispatch.key_generator"   => ActiveSupport::LegacyKeyGenerator.new("b3c631c314c0bbca50c1b2843150fe33")
+      )
+
+      endpoint = Proc.new do |e|
+        remote_ip = ActionDispatch::Request.new(e).remote_ip
+        [200, {}, ["Hello"]]
+      end
+
+      Rails.application.middleware.build(endpoint).call(env)
+      remote_ip
+    end
+
+    test "remote_ip works" do
+      make_basic_app
+      assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1")
+    end
+
+    test "checks IP spoofing by default" do
+      make_basic_app
+      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 "works with both headers individually" do
+      make_basic_app
+      assert_nothing_raised do
+        assert_equal "1.1.1.1", remote_ip("HTTP_X_FORWARDED_FOR" => "1.1.1.1")
+      end
+      assert_nothing_raised do
+        assert_equal "1.1.1.2", remote_ip("HTTP_CLIENT_IP" => "1.1.1.2")
+      end
+    end
+
+    test "can disable IP spoofing check" do
+      make_basic_app do |app|
+        app.config.action_dispatch.ip_spoofing_check = false
+      end
+
+      assert_nothing_raised do
+        assert_equal "1.1.1.1", remote_ip("HTTP_X_FORWARDED_FOR" => "1.1.1.1", "HTTP_CLIENT_IP" => "1.1.1.2")
+      end
+    end
+
+    test "remote_ip works with HTTP_X_FORWARDED_FOR" do
+      make_basic_app
+      assert_equal "4.2.42.42", remote_ip("REMOTE_ADDR" => "1.1.1.1", "HTTP_X_FORWARDED_FOR" => "4.2.42.42")
+    end
+
+    test "the user can set trusted proxies" do
+      make_basic_app do |app|
+        app.config.action_dispatch.trusted_proxies = /^4\.2\.42\.42$/
+      end
+
+      assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1", "HTTP_X_FORWARDED_FOR" => "4.2.42.42")
+    end
+
+    test "the user can set trusted proxies with an IPAddr argument" do
+      make_basic_app do |app|
+        app.config.action_dispatch.trusted_proxies = IPAddr.new("4.2.42.0/24")
+      end
+
+      assert_equal "1.1.1.1", remote_ip("REMOTE_ADDR" => "1.1.1.1", "HTTP_X_FORWARDED_FOR" => "10.0.0.0,4.2.42.42")
+    end
+  end
+end