ftpfs.sh

#! /bin/bash

SSH_PROXY=ssh.proxy.tld
SSH_USER=user
LOCAL_PORT=6666
FTP_USER=ftpuser
FTP_PASS=password123
FTP=0.0.0.0
MOUNT_PATH=~/ftp
OWNER=user

unmount_ftp() {
	echo "Unmounting"
	umount $MOUNT_PATH 2&> /dev/null
	echo "Killing previous port forwarding."
	awk_command="/$LOCAL_PORT/ {split(\$6,a,\",\"); split(a[2],b,\"=\"); print b[2]}"
	kill -n 9 `ss -nltp | awk "$awk_command" | head -n 1`
}

mount_ftp() {
	unmount_ftp
	echo "Setting up dynamic port forwarding."
	ssh -D $LOCAL_PORT -fN $SSH_USER@$SSH_PROXY

	echo "Creating mount folder."
	mkdir -p $MOUNT_PATH

	echo "Mounting ftp system."
	owner_id=`id -u $OWNER`
	owner_group=`id -g $OWNER`
	curlftpfs -o proxy=localhost:$LOCAL_PORT,socks5,user=$FTP_USER:$FTP_PASS,uid=$owner_id,gid=$owner_group $FTP $MOUNT_PATH && echo "FTP mounted at $MOUNT_PATH."
}

main_function() {
	subcmd="$1"
	case "$subcmd" in
		mount )
			mount_ftp
			;;

		unmount )
			unmount_ftp
			;;
		* )
			echo "Unknown subcommand: $subcmd"
			echo "Usage : 'ftpfs.sh mount' or 'ftpfs.sh unmount'"
			;;
	esac
}

main_function "$@"