Simple daemon to use tmate to control a remote machine behind NAT. Uses tmate to generate sessions and save them in a cloud-sync provider folder (ex Dropbox or GDrive)

tmate-daemon.sh

#!/bin/bash

IP=$(ip a s wlp3s0 | grep inet | awk '{print $2}' | head -n 1)
while true; do
    ping -q -w 1 -c 1 `ip r | grep default | awk '{print $3}'` > /dev/null
    # No internet connection
    if (( $? != 0 )); then
        sleep 20s
        ping -q -w 1 -c 1 `ip r | grep default | awk '{print $3}'` > /dev/null
        if (( $? != 0 )); then
            echo "Lost connection, reset ssh"
            touch /path/to/Cloud-sync-service/.ssh_control/.reset_ssh
        fi
    fi

    # Check if changed ip, if true, reset_ssh and update the ip
    TMPIP=$(ip a s wlp3s0 | grep inet | awk '{print $2}' | head -n 1)
    echo $TMPIP
    echo $IP
    if [[ "$TMPIP" == "$IP" ]]; then
        # Check if I have to reset or block_ssh
        if [ -e /path/to/Cloud-sync-service/.ssh_control/.reset_ssh -o -e /path/to/Cloud-sync-service/.ssh_control/.block_ssh ]; then
            echo "Resetting all Sockets"
            killall tmate
            rm -rf /path/to/Cloud-sync-service/.ssh_control/.reset_ssh
        fi
        if [ ! -e /path/to/Cloud-sync-service/.ssh_control/.block_ssh ]; then
            ps aux | grep -v grep | grep tmate.sock
            if (( $? == 0 )); then
                /usr/bin/tmate -S /tmp/tmate.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key.txt
            else    
                unset TMUX
                ps aux | grep '/usr/bin/tmate -S /tmp/tmate.sock new-session -d' | grep -v grep | awk '{print $2}' | xargs kill -9
                /usr/bin/tmate -S /tmp/tmate.sock new-session -d
                sleep 20s
                /usr/bin/tmate -S /tmp/tmate.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key.txt
            fi
            ps aux | grep -v grep | grep tmate-2.sock
            if (( $? == 0 )); then
                /usr/bin/tmate -S /tmp/tmate-2.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-2.txt
            else    
                unset TMUX
                ps aux | grep '/usr/bin/tmate -S /tmp/tmate-2.sock new-session -d' | grep -v grep | awk '{print $2}' | xargs kill -9
                /usr/bin/tmate -S /tmp/tmate-2.sock new-session -d
                sleep 20s
                /usr/bin/tmate -S /tmp/tmate-2.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-2.txt
            fi
            ps aux | grep -v grep | grep tmate-3.sock
            if (( $? == 0 )); then
                /usr/bin/tmate -S /tmp/tmate-3.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-3.txt
            else    
                unset TMUX
                ps aux | grep '/usr/bin/tmate -S /tmp/tmate-3.sock new-session -d' | grep -v grep | awk '{print $2}' | xargs kill -9
                /usr/bin/tmate -S /tmp/tmate-3.sock new-session -d
                sleep 20s
                /usr/bin/tmate -S /tmp/tmate-3.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-3.txt
            fi
            ps aux | grep -v grep | grep tmate-4.sock
            if (( $? == 0 )); then
                /usr/bin/tmate -S /tmp/tmate-4.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-4.txt
            else    
                unset TMUX
                ps aux | grep '/usr/bin/tmate -S /tmp/tmate-4.sock new-session -d' | grep -v grep | awk '{print $2}' | xargs kill -9
                /usr/bin/tmate -S /tmp/tmate-4.sock new-session -d
                sleep 20s
                /usr/bin/tmate -S /tmp/tmate-4.sock display -p '#{tmate_ssh}' > /path/to/Cloud-sync-service/.ssh-key-4.txt
            fi
            chmod +x /path/to/Cloud-sync-service/.ssh-key*.txt
        else
            echo "Connections Blocked"
        fi
    else
        echo "Changed ip, reset ssh"
        IP=$TMPIP
        touch /path/to/Cloud-sync-service/.ssh_control/.reset_ssh
    fi
    sleep 20s
done