1 files changed, 52 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/metal/content_security_policy.rb b/actionpack/lib/action_controller/metal/content_security_policy.rb
new file mode 100644
index 0000000000..b8fab4ebe3
--- /dev/null
+++ b/actionpack/lib/action_controller/metal/content_security_policy.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module ActionController #:nodoc:
+  module ContentSecurityPolicy
+    # TODO: Documentation
+    extend ActiveSupport::Concern
+
+    include AbstractController::Helpers
+    include AbstractController::Callbacks
+
+    included do
+      helper_method :content_security_policy?
+      helper_method :content_security_policy_nonce
+    end
+
+    module ClassMethods
+      def content_security_policy(enabled = true, **options, &block)
+        before_action(options) do
+          if block_given?
+            policy = current_content_security_policy
+            yield policy
+            request.content_security_policy = policy
+          end
+
+          unless enabled
+            request.content_security_policy = nil
+          end
+        end
+      end
+
+      def content_security_policy_report_only(report_only = true, **options)
+        before_action(options) do
+          request.content_security_policy_report_only = report_only
+        end
+      end
+    end
+
+    private
+
+      def content_security_policy?
+        request.content_security_policy
+      end
+
+      def content_security_policy_nonce
+        request.content_security_policy_nonce
+      end
+
+      def current_content_security_policy
+        request.content_security_policy.try(:clone) || ActionDispatch::ContentSecurityPolicy.new
+      end
+  end
+end