networking

nzx_tmpmail/network/lmtp.go

@@ -11,12 +11,14 @@ import (
 )
 
 type Session struct {
-	Conn       net.Conn
+	Conn        net.Conn
-	Reader     *bufio.Reader
+	Reader      *bufio.Reader
-	Writer     *bufio.Writer
+	Writer      *bufio.Writer
-	MailFrom   string
+	MailFrom    string
-	RcptTo     []string
+	RcptTo      []string
-	RemoteAddr string
+	RemoteAddr  string
+	hasMailFrom bool
+	hasRcptTo   bool
 }
 
 func init() {
@@ -62,11 +64,60 @@ func handle_conn(conn net.Conn) {
 		upper := strings.ToUpper(l)
 
 		switch {
+		case strings.HasPrefix(upper, "LHLO "):
+			s.reply("250-nzx056.love")
+			s.reply("250-8BITMIME")
+			s.reply("250 PIPELINING")
+		case strings.HasPrefix(upper, "MAIL FROM:"):
+			s.MailFrom = extractSender(l[len("MAIL FROM:"):])
+			s.hasMailFrom = true
+			s.RcptTo = nil
+			s.reply("250 2.1.0 Ok")
+		case strings.HasPrefix(upper, "RCPT TO:"):
+			rcpt := strings.ToLower(extractSender(l[len("RCPT TO:"):]))
+			s.hasRcptTo = false
 
+			if !strings.HasSuffix(rcpt, "@nzx056.love") {
+				s.reply("550 5.1.1 User unknown")
+				loggingshit.Log("got an email for unknown domain %s, skipping", 1, rcpt)
+				continue
+			}
+
+			s.RcptTo = append(s.RcptTo, rcpt)
+			s.reply("250 2.1.5 Ok")
+		case upper == "DATA":
+			if !s.hasMailFrom {
+				s.reply("503 5.5.1 Need MAIL FROM first")
+				continue
+			}
+
+			if !s.hasRcptTo {
+				s.reply("503 5.5.1 Need RCPT TO first")
+				continue
+			}
+
+			s.reply("354 End data with <CR><LF>.<CR><LF>")
 		}
 	}
 }
 
+func extractSender(s string) string {
+	s = strings.TrimSpace(s)
+	if strings.HasPrefix(s, "<") {
+		end := strings.Index(s, ">")
+		if end >= 0 {
+			return s[1:end]
+		}
+	}
+
+	fields := strings.Fields(s)
+	if len(fields) == 0 {
+		return ""
+	}
+
+	return strings.Trim(fields[0], "<>")
+}
+
 func (s *Session) readline() (string, error) {
 	l, err := s.Reader.ReadString('\n')
 	if err != nil {