Fix parser. Tested with go-fuzz

irc.go

@@ -20,6 +20,7 @@ package irc
 
 import (
 	"bufio"
+	"bytes"
 	"crypto/tls"
 	"errors"
 	"fmt"
@@ -74,18 +75,44 @@ func (irc *Connection) readLoop() {
 			}
 
 			irc.lastMessage = time.Now()
-			msg = msg[:len(msg)-2] //Remove \r\n
+			event, err := parseToEvent(msg)
-			event := &Event{Raw: msg, Connection: irc}
+			event.Connection = irc
+			if err == nil {
+				/* XXX: len(args) == 0: args should be empty */
+				irc.RunCallbacks(event)
+			}
+		}
+	}
+	return
+}
+
+// +build gofuzz
+func Fuzz(data []byte) int {
+	b := bytes.NewBuffer(data)
+	err, _ := parseToEvent(b.String())
+	if err == nil {
+		return 1
+	}
+	return 0
+}
+
+//Parse raw irc messages
+func parseToEvent(msg string) (*Event, error) {
+	msg = strings.TrimSpace(msg) //Remove \r\n
+	event := &Event{Raw: msg}
+	if len(msg) < 5 {
+		return nil, errors.New("Malformed msg from server")
+	}
 	if msg[0] == ':' {
 		if i := strings.Index(msg, " "); i > -1 {
 			event.Source = msg[1:i]
 			msg = msg[i+1 : len(msg)]
 
 		} else {
-					irc.Log.Printf("Misformed msg from server: %#s\n", msg)
+			return nil, errors.New("Malformed msg from server")
 		}
 
-				if i, j := strings.Index(event.Source, "!"), strings.Index(event.Source, "@"); i > -1 && j > -1 {
+		if i, j := strings.Index(event.Source, "!"), strings.Index(event.Source, "@"); i > -1 && j > -1 && i < j {
 			event.Nick = event.Source[0:i]
 			event.User = event.Source[i+1 : j]
 			event.Host = event.Source[j+1 : len(event.Source)]
@@ -99,12 +126,8 @@ func (irc *Connection) readLoop() {
 	if len(split) > 1 {
 		event.Arguments = append(event.Arguments, split[1])
 	}
+	return event, nil
 
-			/* XXX: len(args) == 0: args should be empty */
-			irc.RunCallbacks(event)
-		}
-	}
-	return
 }
 
 // Loop to write to a connection. To be used as a goroutine.