diff --git a/main.go b/main.go
index 3de1365..ff61e96 100644
--- a/main.go
+++ b/main.go
@@ -22,7 +22,12 @@ func main() {
 	})
 
 	publicKeyOption := ssh.PublicKeyAuth(func(ctx ssh.Context, key ssh.PublicKey) bool {
-		return true // allow all keys, or use ssh.KeysEqual() to compare against known keys
+		log.Println("type: ", key.Type())
+		if key.Type() == "sk-ecdsa-sha2-nistp256@openssh.com" {
+			return true
+		}
+		return false
+		//return true // allow all keys, or use ssh.KeysEqual() to compare against known keys
 	})
 	log.Println("Listening :222...")
 	log.Fatal(ssh.ListenAndServe(":2222", nil, publicKeyOption))