Cheap SOCKS proxy using an SSH tunnel.

tunnel.sh

#!/bin/bash
# Launch SSH tunnel for SOCKS proxy.

set -euo pipefail

host="$1"
local_port=1080

control_dir="$(dirname "$(mktemp -u)")"
control_path="$control_dir/ssh-control-%r@%h:%p"

trap 'echo "Failed to connect to host or control"' ERR

ssh -D $local_port -S "$control_path" -fNM "$host"
echo "Opened tunnel to $host. Use SOCKS v5 proxy, host 127.0.0.1:$local_port."

ssh -S "$control_path" -O check "$host"
control_path_expanded=$(ssh -S "$control_path" -G "$host" | grep "^controlpath " | sed "s/.* //g")

echo "Exit with \"ssh -S $control_path_expanded -O exit $host\""