Support SMTP Auth Plain

server/smtp_server.go

@@ -70,15 +70,20 @@ func (b *smtpBackend) Counts() (total int64, success int64, failure int64) {
 
 // smtpSession is returned after EHLO.
 type smtpSession struct {
-	backend *smtpBackend
-	conn    *smtp.Conn
-	topic   string
-	token   string
-	mu      sync.Mutex
+	backend    *smtpBackend
+	conn       *smtp.Conn
+	topic      string
+	token      string
+	mu         sync.Mutex
+	basic_auth string
 }
 
-func (s *smtpSession) AuthPlain(username, _ string) error {
+func (s *smtpSession) AuthPlain(username, password string) error {
 	logem(s.conn).Field("smtp_username", username).Debug("AUTH PLAIN (with username %s)", username)
+	basic_auth := base64.StdEncoding.EncodeToString([]byte(fmt.Sprintf("%s:%s", username, password)))
+	s.mu.Lock()
+	s.basic_auth = basic_auth
+	s.mu.Unlock()
 	return nil
 }
 
@@ -198,6 +203,8 @@ func (s *smtpSession) publishMessage(m *message) error {
 	}
 	if s.token != "" {
 		req.Header.Add("Authorization", "Bearer "+s.token)
+	} else if s.basic_auth != "" {
+		req.Header.Add("Authorization", "Basic "+s.basic_auth)
 	}
 	rr := httptest.NewRecorder()
 	s.backend.handler(rr, req)
@@ -214,6 +221,9 @@ func (s *smtpSession) Reset() {
 }
 
 func (s *smtpSession) Logout() error {
+	s.mu.Lock()
+	s.basic_auth = ""
+	s.mu.Unlock()
 	return nil
 }