Add outbound requests setting for system hooks

This MR adds new application setting to network section
`allow_local_requests_from_system_hooks`. Prior to this change
system hooks were allowed to do local network requests by default
and we are adding an ability for admins to control it.

2 files changed, 31 insertions, 1 deletions

diff --git a/app/validators/addressable_url_validator.rb b/app/validators/addressable_url_validator.rb
index 273e15ef925..bb445499cee 100644
--- a/app/validators/addressable_url_validator.rb
+++ b/app/validators/addressable_url_validator.rb
@@ -107,6 +107,6 @@ class AddressableUrlValidator < ActiveModel::EachValidator
     # calls this validator.
     #
     # See https://gitlab.com/gitlab-org/gitlab-ee/issues/9833
-    ApplicationSetting.current&.allow_local_requests_from_hooks_and_services?
+    ApplicationSetting.current&.allow_local_requests_from_web_hooks_and_services?
   end
 end
diff --git a/app/validators/system_hook_url_validator.rb b/app/validators/system_hook_url_validator.rb
new file mode 100644
index 00000000000..c8c0007e35b
--- /dev/null
+++ b/app/validators/system_hook_url_validator.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+# SystemHookUrlValidator
+#
+# Custom validator specifically for SystemHook URLs. This validator works like AddressableUrlValidator but
+# it blocks urls pointing to localhost or the local network depending on
+# ApplicationSetting.allow_local_requests_from_system_hooks
+#
+# Example:
+#
+#   class SystemHook < WebHook
+#     validates :url, system_hook_url: { allow_localhost: true, allow_local_network: true }
+#   end
+#
+class SystemHookUrlValidator < AddressableUrlValidator
+  DEFAULT_OPTIONS = {
+    allow_localhost: true,
+    allow_local_network: true
+  }.freeze
+
+  def initialize(options)
+    options.reverse_merge!(DEFAULT_OPTIONS)
+
+    super(options)
+  end
+
+  def self.allow_setting_local_requests?
+    ApplicationSetting.current&.allow_local_requests_from_system_hooks?
+  end
+end