[Unit]
Description=Dropbear SSH daemon
After=syslog.target network.target auditd.service

[Service]
# If /etc/dropbear is a symlink to /var/run/dropbear, and
#   - the filesystem is RO (i.e. we can not rm the symlink),
#     create the directory pointed to by the symlink.
#   - the filesystem is RW (i.e. we can rm the symlink),
#     replace the symlink with an actual directory
ExecStartPre=/bin/sh -c '\
if [ -L /etc/dropbear \
     -a "$(readlink /etc/dropbear)" = "/var/run/dropbear" ]; then \
    if rm -f /etc/dropbear >/dev/null 2>&1; then \
        mkdir -p /etc/dropbear; \
    else \
        echo "No persistent location to store SSH host keys. New keys will be"; \
        echo "generated at each boot. Are you sure this is what you want to do?"; \
        mkdir -p "$(readlink /etc/dropbear)"; \
    fi; \
fi'
ExecStart=/usr/sbin/dropbear -F -R
ExecReload=/bin/kill -HUP $MAINPID

[Install]
WantedBy=multi-user.target