Renaming package to ShadowArch to follow /wiki/Design_Principles; improved packing; development sync to current state -- massive overhaul

AdminScripts/revproxy

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+#!/bin/bash
+
+# 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 $?
+fi
+
+if [ ! -z "$1" ] && [ "$1" == "--list" ]; then
+    iptables -S -t nat
+    exit $?
+fi
+
+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
+fi
+
+# Tell the kernel to allow forwarding packets.
+echo 1 > /proc/sys/net/ipv4/ip_forward
+
+# 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;
+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"