From a70b1488210f92bfe8bcd6474b898a31b23e0a90 Mon Sep 17 00:00:00 2001
From: Bernhard Froehlich <decke@bluelife.at>
Date: Wed, 12 Dec 2018 08:38:13 +0000
Subject: [PATCH] Allow remote authentication to be optional

---
 main.go | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/main.go b/main.go
index b74661d..9a45ccc 100644
--- a/main.go
+++ b/main.go
@@ -27,11 +27,16 @@ var (
 
 func handler(peer smtpd.Peer, env smtpd.Envelope) error {
 
+	var auth smtp.Auth
 	host, _, _ := net.SplitHostPort(*remoteHost)
 
+	if *remoteUser != "" && *remotePass != "" {
+		auth = smtp.PlainAuth("", *remoteUser, *remotePass, host)
+	}
+
 	return smtp.SendMail(
 		*remoteHost,
-		smtp.PlainAuth("", *remoteUser, *remotePass, host),
+		auth,
 		env.Sender,
 		env.Recipients,
 		env.Data,