pihole_ynh/conf/dnsmasq_regenconf_hook

#!/bin/bash

source /usr/share/yunohost/helpers

force=${2:-0}  # 0/1 --force argument
dryrun=${3:-0}  # 0/1 --dry-run argument
pending_conf=$4 # Path of the pending conf file
app="__APP__"

do_pre_regen() {
    if [ $dryrun -eq 0 ]
    then
        dnsmasq_dir="${pending_conf}/etc/dnsmasq.d"
        mkdir -p "$dnsmasq_dir"
        cp -a "/etc/dnsmasq.conf" "${pending_conf}/etc/dnsmasq.conf"
        # Créer une sauvegarde des config dnsmasq de pi-hole. Que la regen-conf va sauvagement supprimer
        cp -a "/etc/dnsmasq.d/01-pihole.conf" "$dnsmasq_dir/"

        ynh_replace_string --match_string="^cache-size=" --replace_string="#pihole# cache-size=" --target_file="${pending_conf}/etc/dnsmasq.conf"

        enable_dhcp=$(ynh_app_setting_get --app=$app --key=enable_dhcp)
        if [ $enable_dhcp -eq 1 ]
        then

            # Get the default network interface
            main_iface=$(ip route | grep --max-count=1 default | awk '{print $5;}')
            # Find the IP associated to the network interface
            localipv4=$(ip address | grep "${main_iface}\$" | awk '{print $2;}' | cut -d/ -f1)

            max_dhcp_range=250
            dhcp_range=100
            
            # Define the dhcp range from the current ip
            ip_beginning_part=$(echo "$localipv4" | cut -d. -f1-3)
            ip_fourth_part=$(echo "$localipv4" | cut -d. -f4)
            b_range=$(( $ip_fourth_part + $dhcp_range ))
            if [ $b_range -gt $max_dhcp_range ]; then
                b_range=$max_dhcp_range
            fi
            a_range=$(( $b_range - $dhcp_range ))

            # Get the gateway
            gateway=$(ip route | grep default | awk '{print $3;}')
            # And the mac adress
            hw_adress=$(ip link | grep -A1 "$main_iface" | tail -n1 | awk '{print $2;}')

            # Copy the config file
            cp -a "/etc/yunohost/apps/$app/conf/02-pihole-dhcp.conf" "$dnsmasq_dir/"

            # And set the config
            ynh_replace_string --match_string="__A_RANGE__" --replace_string="$ip_beginning_part.$a_range" --target_file="${pending_conf}/etc/dnsmasq.d/02-pihole-dhcp.conf"
            ynh_replace_string --match_string="__B_RANGE__" --replace_string="$ip_beginning_part.$b_range" --target_file="${pending_conf}/etc/dnsmasq.d/02-pihole-dhcp.conf"
            ynh_replace_string --match_string="__GATEWAY__" --replace_string="$gateway" --target_file="${pending_conf}/etc/dnsmasq.d/02-pihole-dhcp.conf"

            # Set a static ip for the server.
            echo "dhcp-host=$hw_adress,$localipv4" > "${pending_conf}/etc/dnsmasq.d/04-pihole-static-dhcp.conf"
        fi
    fi
}

do_post_regen() {
    # Reload dnsmasq
    systemctl reload dnsmasq
}

case "$1" in
    pre)
        do_pre_regen
        ;;
    post)
        do_post_regen
        ;;
    *)
        echo "Hook called with unknown argument \`$1'" >&2
        exit 1
        ;;
esac

exit 0