More commands, better connection handling/logging

mailhog/config.go

@@ -0,0 +1,13 @@
+package mailhog
+
+func DefaultConfig() *Config {
+	return &Config{
+		BindAddr: "0.0.0.0:1025",
+		Hostname: "mailhog.example",
+	}
+}
+
+type Config struct {
+	BindAddr string
+	Hostname string
+}

mailhog/smtp/smtp.go

@@ -6,13 +6,23 @@ import (
 	"log"
 	"net"
 	"strings"
+	"github.com/ian-kent/MailHog/mailhog"
 )
 
 type Session struct {
 	conn *net.TCPConn
 	line string
+	conf *mailhog.Config
+	state int
 }
 
+const (
+	ESTABLISH = iota
+	MAIL
+	RCPT
+	DATA
+)
+
 type Message struct {
 	From string
 	To string
@@ -20,19 +30,20 @@ type Message struct {
 	Helo string
 }
 
-func StartSession(conn *net.TCPConn) {
+func StartSession(conn *net.TCPConn, conf *mailhog.Config) {
-	conv := &Session{conn, ""}
+	conv := &Session{conn, "", conf, ESTABLISH}
-	log.Printf("Starting session with %s", conn.RemoteAddr())
+	conv.log("Starting session")
-	conv.Begin()
+	conv.Write("220", "Go-MailHog")
+	conv.Read()
 }
 
-func (c Session) log(message string, args ...interface{}) {
+func (c *Session) log(message string, args ...interface{}) {
-	message = strings.Join([]string{"[%s]", message}, " ")
+	message = strings.Join([]string{"[%s, %d]", message}, " ")
-	args = append([]interface{}{c.conn.RemoteAddr()}, args...)
+	args = append([]interface{}{c.conn.RemoteAddr(), c.state}, args...)
 	log.Printf(message, args...)
 }
 
-func (c Session) Read() {
+func (c *Session) Read() {
 	buf := make([]byte, 1024)
 	n, err := c.conn.Read(buf)
 
@@ -45,26 +56,29 @@ func (c Session) Read() {
 		return
 	}
 
-	text := string(buf)
+	text := string(buf[0:n])
-	c.log("Received %d bytes: %s\n", n, text)
+	c.log("Received %d bytes: '%s'\n", n, text)
 
 	c.line += text
 
 	c.Parse()
 }
 
-func (c Session) Parse() {
+func (c *Session) Parse() {
 	for strings.Contains(c.line, "\n") {
 		parts := strings.SplitN(c.line, "\n", 2)
+		if len(parts) == 2 {
 			c.line = parts[1]
-		c.log("Parsing string: %s", parts[0])
+		} else {
+			c.line = ""
+		}
 		c.Process(strings.Trim(parts[0], "\r\n"))
 	}
 
 	c.Read()
 }
 
-func (c Session) Write(code string, text ...string) {
+func (c *Session) Write(code string, text ...string) {
 	if len(text) == 1 {
 		c.conn.Write([]byte(code + " " + text[0] + "\n"))
 		return
@@ -75,28 +89,43 @@ func (c Session) Write(code string, text ...string) {
 	c.conn.Write([]byte(code + " " + text[len(text)] + "\n"))
 }
 
-func (c Session) Process(line string) {
+func (c *Session) Process(line string) {
 	c.log("Processing line: %s", line)
 
 	words := strings.Split(line, " ")
+	command := words[0]
+	c.log("In state %d, got command '%s'", c.state, command)
 
-	switch words[0] {
+	switch {
+		case command == "RSET":
+			c.log("Got RSET command, switching to ESTABLISH state")
+			c.state = ESTABLISH
+			c.Write("250", "OK")
+		case command == "NOOP":
+			c.log("Got NOOP command")
+			c.Write("250", "OK")
+		case command == "QUIT":
+			c.log("Got QUIT command")
+			c.Write("221", "OK")
+		case c.state == ESTABLISH:
+			switch command {
 				case "HELO": 
-			c.log("Got HELO command")
+					c.log("Got HELO command, switching to MAIL state")
-			c.Write("250", "HELO " + "my.hostname")
+					c.state = MAIL
+					c.Write("250", "HELO " + c.conf.Hostname)
 				case "EHLO":
-			c.log("Got EHLO command")
+					c.log("Got EHLO command, switching to MAIL state")
-			c.Write("250", "HELO " + "my.hostname")
+					c.state = MAIL
+					c.Write("250", "EHLO " + c.conf.Hostname)
 				default:
-			c.log("Got unknown command: '%s'", words[0])
+					c.log("Got unknown command for ESTABLISH state: '%s'", command)
+			}
+		case c.state == MAIL:
+			switch command {
+				case "MAIL":
+					c.log("Got MAIL command")
+				default:
+					c.log("Got unknown command for MAIL state: '%s'", command)
 			}
 	}
-
-func (c Session) Begin() {
-	_, err := c.conn.Write([]byte("220 Go-MailHog\n"))
-	if err != nil {
-		c.log("Failed writing to socket: %s\n", err)
-		return
-	}
-	c.Read()
 }

main.go

@@ -4,13 +4,11 @@ import (
 	"flag"
 	"log"
 	"net"
+	"github.com/ian-kent/MailHog/mailhog"
 	"github.com/ian-kent/MailHog/mailhog/smtp"
 )
 
-var conf = map[string]string {
+var conf *mailhog.Config
-	"BIND_ADDRESS": "0.0.0.0:1025",
-	"HOSTNAME": "mailhog.example",
-}
 
 func config() {
 	var listen, hostname string
@@ -20,14 +18,16 @@ func config() {
 
 	flag.Parse()
 
-	conf["BIND_ADDRESS"] = listen
+	conf = &mailhog.Config{
-	conf["HOSTNAME"] = hostname
+		BindAddr: listen,
+		Hostname: hostname,
+	}
 }
 
 func main() {
 	config()
 
-	ln := listen(conf["BIND_ADDRESS"])
+	ln := listen(conf.BindAddr)
 	defer ln.Close()
 
 	for {
@@ -38,7 +38,7 @@ func main() {
 		}
 		defer conn.Close()
 
-		go smtp.StartSession(conn.(*net.TCPConn))
+		go smtp.StartSession(conn.(*net.TCPConn), conf)
 	}
 }
 
@@ -50,23 +50,3 @@ func listen(bind string) (*net.TCPListener) {
 	}
 	return ln.(*net.TCPListener)
 }
-
-func accept(conn net.Conn) {
-	buf := make([]byte, 1024)	
-	n, err := conn.Read(buf)
-
-	if err != nil {
-		log.Printf("Error reading from socket: %s", err)
-		return
-	}
-
-	log.Printf("Received %s bytes: %s\n", n, string(buf))
-
-	_, err = conn.Write(buf)
-	if err != nil {
-		log.Printf("Error writing to socket: %s\n", err)
-		return
-	}
-
-	log.Printf("Reply sent\n")
-}