Enable Content-Security-Policy to prevent Searchworks from being embe…

…dded in a frame

config/initializers/content_security_policy.rb

@@ -4,22 +4,25 @@
 # See the Securing Rails Applications Guide for more information:
 # https://guides.rubyonrails.org/security.html#content-security-policy-header
 
-# Rails.application.configure do
-#   config.content_security_policy do |policy|
-#     policy.default_src :self, :https
-#     policy.font_src    :self, :https, :data
-#     policy.img_src     :self, :https, :data
-#     policy.object_src  :none
-#     policy.script_src  :self, :https
-#     policy.style_src   :self, :https
-#     # Specify URI for violation reports
-#     # policy.report_uri "/csp-violation-report-endpoint"
-#   end
-#
-#   # Generate session nonces for permitted importmap, inline scripts, and inline styles.
-#   config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
-#   config.content_security_policy_nonce_directives = %w(script-src style-src)
-#
-#   # Report violations without enforcing the policy.
-#   # config.content_security_policy_report_only = true
-# end
+Rails.application.configure do
+  config.content_security_policy do |policy|
+    # policy.default_src :self, :https
+    # policy.font_src    :self, :https, :data
+    # policy.img_src     :self, :https, :data
+    # policy.object_src  :none
+    # policy.script_src  :self, :https
+    # policy.style_src   :self, :https
+    # Specify URI for violation reports
+    # policy.report_uri "/csp-violation-report-endpoint"
+
+    # Prevent this site from being opened in a <frame> or <iframe> (replaces X-Frame-Options: sameorigin)
+    policy.frame_ancestors :self
+  end
+
+  # Generate session nonces for permitted importmap, inline scripts, and inline styles.
+  config.content_security_policy_nonce_generator = ->(request) { request.session.id.to_s }
+  config.content_security_policy_nonce_directives = %w(script-src style-src)
+
+  # Report violations without enforcing the policy.
+  # config.content_security_policy_report_only = true
+end