externalAddress, ok := r.RequestHeaders["X-Envoy-External-Address"]
						if !ok {
							return fmt.Errorf("missing X-Envoy-External-Address Header")
						}
						if err := ExpectString(externalAddress[0], "72.9.5.6", "envoy-external-address header"); err != nil {
							return err
						}
						xffHeader, ok := r.RequestHeaders["X-Forwarded-For"]
						if !ok {