From d1a35d0cce96228bdf046126f8bd57a322f4eb05 Mon Sep 17 00:00:00 2001
From: arzumify <jliwin98@danwin1210.de>
Date: Mon, 25 Nov 2024 15:52:51 +0000
Subject: [PATCH] Fixed authbackend to include the initial line

---
 smtp.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/smtp.go b/smtp.go
index d40183d..1cc0fad 100644
--- a/smtp.go
+++ b/smtp.go
@@ -58,7 +58,7 @@ type DatabaseBackend struct {
 
 // AuthenticationBackend is a struct that represents an authentication backend
 type AuthenticationBackend struct {
-	Authenticate func(conn *textproto.Conn) (*Address, error)
+	Authenticate func(initial string, conn *textproto.Conn) (*Address, error)
 }
 
 func readMultilineCodeResponse(conn *textproto.Conn) (int, string, error) {
@@ -320,7 +320,7 @@ func (fr *Receiver) handleConnection(conn net.Conn) {
 				}
 				continue
 			} else {
-				address, err := fr.auth.Authenticate(textProto)
+				address, err := fr.auth.Authenticate(strings.TrimPrefix(line, "AUTH "), textProto)
 				if err != nil {
 					_ = textProto.PrintfLine("421 4.7.0 Temporary server error")
 					_ = conn.Close()