Create a sock proxy at a random port that helps you to connect to a private network from your computer

gen_sockproxy.sh

#! /bin/bash

SSH_KEY=$1
BASTION_IP=$2
USERNAME=$3
PROXY_PORT=`comm -23 <(seq 13000 13999 | sort) <(netstat -tan | awk '{print $4}' | cut -d':' -f2 | sort -u) | shuf | head -n 1`
ssh -i "$SSH_KEY" -CND "${PROXY_PORT}" -q "${USERNAME}@${BASTION_IP}" &

echo "socks5://localhost:$PROXY_PORT"