Tunnel a TCP request through a remote server

tunnel-request-through-remote-server.sh

#!/bin/bash

SSH_HOST=YOUR-REMOTE-SSH-SERVER-HOST
SSH_PORT=YOUR-REMOTE-SSH-SERVER-PORT
LOCAL_HOST=127.0.0.1
LOCAL_PORT=8888

read -p 'Target Host/IP: ' TARGET_HOST
read -p 'Target Port: ' TARGET_PORT

IPTABLES_RULE="OUTPUT -p tcp -d $TARGET_HOST --dport $TARGET_PORT -j DNAT --to-destination $LOCAL_HOST:$LOCAL_PORT"

function finish {
  sudo iptables -t nat -D $IPTABLES_RULE
  echo "Deleted iptables entry for $TARGET_HOST:$TARGET_PORT"
}
trap finish EXIT

sudo sysctl net.ipv4.ip_forward=1
sudo iptables -t nat -A $IPTABLES_RULE
echo "Added iptables entry for $TARGET_HOST:$TARGET_PORT"

echo "Connecting to ssh server $SSH_HOST:$SSH_PORT"
ssh -N -L $LOCAL_PORT:$TARGET_HOST:$TARGET_PORT $SSH_HOST -p $SSH_PORT