Added configuration files and TLS listening option

cmd/server/config.go

@@ -0,0 +1,59 @@
+/* diodemail - send-only smtp server
+ * Copyright (c) 2024 Gnarwhal
+ *
+ * This file is part of SSHare.
+ *
+ * SSHare is free software: you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * SSHare is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * SSHare. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package main
+
+import (
+	"os"
+	"encoding/json"
+)
+
+type Config struct {
+	Host  string
+	Plain PlainConfig
+	TLS   TLSConfig
+}
+
+type PlainConfig struct {
+	Enabled bool
+	Port    string
+}
+
+type TLSConfig struct {
+	Enabled        bool
+	Port           string
+	CertPath       string
+	PrivateKeyPath string
+}
+
+func LoadConfig(path string) (*Config, error) {
+	contents, err := os.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	var config Config
+	config.Plain.Enabled = false
+	config.Plain.Port    = "25"
+	config.TLS.Enabled   = false
+	config.TLS.Port      = "465"
+	err = json.Unmarshal(contents, &config)
+	if err != nil {
+		return nil, err
+	}
+	return &config, nil
+}

cmd/server/main.go

@@ -20,15 +20,48 @@ package main
 
 import (
 	"log"
+	"flag"
+	"crypto/tls"
 	
 	"forge.monodon.me/Gnarwhal/diodemail/smtp"
 )
 
 func main() {
-	err := smtp.Run(
-		"localhost",
-		"4650",
-		false,
+	var cert_path string
+	flag.StringVar(&cert_path, "config", "/etc/diodemail/config.json", "Path to config file")
+	flag.Parse()
+	config, err := LoadConfig(cert_path)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var plain_config *smtp.PlainConfig
+	if config.Plain.Enabled {
+		plain_config = &smtp.PlainConfig {
+			config.Plain.Port,
+		}
+	}
+
+	var tls_config *smtp.TLSConfig
+	if config.TLS.Enabled {
+		certificate, err := tls.LoadX509KeyPair(
+			config.TLS.CertPath,
+			config.TLS.PrivateKeyPath,
+		)
+		if err != nil {
+			log.Println(err)
+		} else {
+			tls_config = &smtp.TLSConfig {
+				config.TLS.Port,
+				tls.Config{Certificates: []tls.Certificate{certificate}},
+			}
+		}
+	}
+
+	err = smtp.Run(
+		config.Host,
+		plain_config,
+		tls_config,
 	)
 	if err != nil {
 		log.Fatal(err)

smtp/server.go

@@ -21,14 +21,21 @@ package smtp
 import (
 	"fmt"
 	"net"
+	"crypto/tls"
 	"os"
+	"sync"
 
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
 )
 
-type PlainListener struct {
-	listener net.Listener
+type PlainConfig struct {
+	Port string
+}
+
+type TLSConfig struct {
+	Port      string
+	TlsConfig tls.Config
 }
 
 func handle(connection net.Conn, host string) {
@@ -54,7 +61,7 @@ func handle(connection net.Conn, host string) {
 	}
 }
 
-func Run(host string, port string, implicit_tls bool) error {
+func Run(host string, plain_config *PlainConfig, tls_config *TLSConfig) error {
 	log.Logger = zerolog.
 		New(zerolog.ConsoleWriter{Out: os.Stderr}).
 		With().
@@ -62,22 +69,35 @@ func Run(host string, port string, implicit_tls bool) error {
 		Logger().
 		Level(zerolog.TraceLevel)
 
-	listener, err := net.Listen("tcp", fmt.Sprintf("%v:%v", host, port))
+	var wait_group sync.WaitGroup
+	if plain_config != nil {
+		listener, err := net.Listen("tcp", fmt.Sprintf("%v:%v", host, plain_config.Port))
 		if err != nil {
 			return err
 		}
+		log.Info().Msgf("Plain text server started on port %v for host %v", plain_config.Port, host)
+		wait_group.Add(1)
+		go Listen(wait_group, host, listener)
+	}
+	if tls_config != nil {
+		listener, err := tls.Listen("tcp", fmt.Sprintf("%v:%v", host, tls_config.Port), &tls_config.TlsConfig)
+		if err != nil {
+			return err
+		}
+		log.Info().Msgf("TLS server started on port %v for host %v", tls_config.Port, host)
+		wait_group.Add(1)
+		go Listen(wait_group, host, listener)
+	}
+	wait_group.Wait()
+
+	return nil
+}
 
-	log.Info().Msgf("Server started on port %v for host %v", port, host)
+func Listen(wait_group sync.WaitGroup, host string, listener net.Listener) {
+	defer wait_group.Done()
 	for {
-		connection, err := listener.Accept()
-		if err != nil {
-			return err
-		}
+		connection, _ := listener.Accept()
 
 		go handle(connection, host)
 	}
 }
-
-func (self PlainListener) Close() error {
-	return self.listener.Close()
-}

smtp/session.go

@@ -149,7 +149,7 @@ func (self *SMTPSession) SendMail(data string) error {
 	} else {
 		smtp_hostname = mx[0].Host
 	}
-	tls_connection, err := tls.Dial("tcp", fmt.Sprintf("%v:4560", smtp_hostname), nil)
+	tls_connection, err := tls.Dial("tcp", fmt.Sprintf("%v:465", smtp_hostname), nil)
 	if err != nil {
 		return err
 	}