From 9910b9ced8a384b40f9d95845263f60a05fe49e4 Mon Sep 17 00:00:00 2001
From: root <root@teamred.aninix.net>
Date: Mon, 30 Jan 2017 12:12:05 -0600
Subject: [PATCH] Fix for revproxy; adding simple-web script.

---
 Admin/Makefile            |  2 +-
 Admin/{proxy => revproxy} | 16 +++++++++++-----
 Admin/simple-web          |  2 ++
 3 files changed, 14 insertions(+), 6 deletions(-)
 rename Admin/{proxy => revproxy} (50%)
 mode change 100644 => 100755
 create mode 100644 Admin/simple-web

diff --git a/Admin/Makefile b/Admin/Makefile
index 71df091..99859c9 100644
--- a/Admin/Makefile
+++ b/Admin/Makefile
@@ -1,4 +1,4 @@
-LIST=arch-update clean-exim clean-exim-input close-guest fix-sound log-guest open-guest restart-service silent-guardian proxy
+LIST=arch-update clean-exim clean-exim-input close-guest fix-sound log-guest open-guest restart-service silent-guardian proxy simple-web
 LOCATION=/root/bin
 PERMISSION=0700
 compile: 
diff --git a/Admin/proxy b/Admin/revproxy
old mode 100644
new mode 100755
similarity index 50%
rename from Admin/proxy
rename to Admin/revproxy
index ff73e0d..43bbb1a
--- a/Admin/proxy
+++ b/Admin/revproxy
@@ -2,6 +2,10 @@
 
 # Establish iptables-based reverse proxy
 
+# Thanks to user55518 in http://unix.stackexchange.com/questions/111841/regular-expression-in-bash-to-validate-ip-address#111843
+re='^[1-2]\{0,1\}[0-9]\{0,1\}[0-9]\{1\}\.[1-2]\{0,1\}[0-9]\{0,1\}[0-9]\{1\}\.[1-2]\{0,1\}[0-9]\{0,1\}[0-9]\{1\}\.[1-2]\{0,1\}[0-9]\{0,1\}[0-9]\{1\}$'
+
+
 if [ ! -z "$1" ] && [ "$1" == "--reset" ]; then
     iptables -F -t nat
     exit $?
@@ -12,8 +16,8 @@ if [ ! -z "$1" ] && [ "$1" == "--list" ]; then
     exit $?
 fi
 
-if [ -z "$1" ] || [ -z "$2" ] || [ -z "$3" ]; then
-    printf "Usage: $0 localport remotehost remoteport [ --local ]\n"
+if [ -z "$1" ] || [ -z "$2" ] || ! (echo "$2" | grep -x "$re" &> /dev/null) || [ -z "$3" ]; then
+    printf "Usage: $0 localport remoteIP remoteport [ --local ]\n"
     printf "       $0 --reset\n"
     printf "       $0 --list\n"
     exit 1
@@ -22,9 +26,6 @@ fi
 # Tell the kernel to allow forwarding packets.
 echo 1 > /proc/sys/net/ipv4/ip_forward
 
-# Default forwarding rule
-iptables -t nat -A PREROUTING -p tcp -m tcp --dport "$1" -j DNAT --to-destination "$2":"$3"
-
 # Set up masquerading if not already done
 if [ `iptables -S -t nat | grep -c '\-A POSTROUTING -j MASQUERADE'` -ne 1 ]; then
     iptables -t nat -A POSTROUTING -j MASQUERADE;
@@ -33,4 +34,9 @@ fi
 # Handle local forwarding.
 if [ "$4" == "--local" ] || [ "$2" == "127.0.0.1" ]; then
     iptables -t nat -I OUTPUT -p tcp -o lo --dport "$1" -j REDIRECT --to-ports "$3"
+    iptables -t nat -A PREROUTING -p tcp --dport "$1" -j REDIRECT --to "$3"
+else  # Handle remote
+    iptables -t nat -A PREROUTING -p tcp -m tcp --dport "$1" -j DNAT --to-destination "$2":"$3"
 fi
+
+echo Done -- all traffic connecting to port "$1" will be redirected to "$2":"$3"
diff --git a/Admin/simple-web b/Admin/simple-web
new file mode 100644
index 0000000..d62f45f
--- /dev/null
+++ b/Admin/simple-web
@@ -0,0 +1,2 @@
+#!/bin/bash
+python3 -m http.server 8000