From 172971a055c3226a1ea9b2cf194c7d13b5d6ac7a Mon Sep 17 00:00:00 2001
From: Hector <dev@hsmith.org>
Date: Sun, 29 Aug 2021 12:03:44 +0100
Subject: [PATCH] fix command writing code

Fix the code writing commands to the fail2ban socket to correctly encode
the command terminator string. The terminator string should be encoded as
a simple byte array, not using the pickle format. Using the pickle format
allowed the first command to succeed, but would "break" the socket in the
sense that all following commands would fail with an underflow exception.
---
 src/socket/protocol.go | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/src/socket/protocol.go b/src/socket/protocol.go
index 905cae1..9dc10f5 100644
--- a/src/socket/protocol.go
+++ b/src/socket/protocol.go
@@ -3,9 +3,7 @@ package socket
 import (
 	"bytes"
 	"fmt"
-	"github.com/kisielk/og-rek"
 	"github.com/nlpodyssey/gopickle/pickle"
-	"net"
 )
 
 const (
@@ -15,28 +13,28 @@ const (
 )
 
 func (s *Fail2BanSocket) sendCommand(command []string) (interface{}, error) {
-	err := write(s.encoder, command)
+	err := s.write(command)
 	if err != nil {
 		return nil, err
 	}
-	return read(&s.socket)
+	return s.read()
 }
 
-func write(encoder *ogórek.Encoder, command []string) error {
-	err := encoder.Encode(command)
+func (s *Fail2BanSocket) write(command []string) error {
+	err := s.encoder.Encode(command)
 	if err != nil {
 		return err
 	}
-	err = encoder.Encode(commandTerminator)
+	_, err = s.socket.Write([]byte(commandTerminator))
 	if err != nil {
 		return err
 	}
 	return nil
 }
 
-func read(s *net.Conn) (interface{}, error) {
+func (s *Fail2BanSocket) read() (interface{}, error) {
 	buf := make([]byte, socketReadBufferSize)
-	_, err := (*s).Read(buf)
+	_, err := s.socket.Read(buf)
 	if err != nil {
 		return nil, err
 	}