cmd/server/main.go | 3 +++

diff --git a/cmd/server/main.go b/cmd/server/main.go
index fd60e914b190568e27db7e55096cb07083e2813f65e07933b736316f0dd9c2fb..86204b86ffca078a9e861369fe11c94b5c9a665c0256473476a4973af158e563 100644
--- a/cmd/server/main.go
+++ b/cmd/server/main.go
@@ -173,6 +173,9 @@
 		var txCS, rxCS *noise.CipherState
 		buf, txCS, rxCS, err := hs.WriteMessage(nil,
 			[]byte(fmt.Sprintf("OK %s", hex.EncodeToString(cookie[:]))))
+		if err != nil {
+			log.Fatalln("hs.WriteMessage:", err)
+		}
 		if err = vors.PktWrite(conn, buf); err != nil {
 			logger.Error("handshake write", "err", err)
 			delete(Cookies, cookie)