update_serial.example

#!/bin/bash
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License version 3 for
# more details.
#
# You should have received a copy of the GNU General Public License version 3
# along with this program; if not, write to the Free Software Foundation, Inc., 51
# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# (c) 2016 Valentin Samir

next=0
for args in "$@"; do
    if [ $next -ge 1 ]; then
        view=$args
        next=0
    fi
    if [[ "$args" = "--view" ]]; then
        next=1
    fi
done

if [ -z "$view" ]; then
    view="internet"
fi

if [[ "$1" = "--view" ]]; then
    shift 2
fi

if [ -z "$1" ]; then
    echo "Usage: $0 (zone_name) [zone_name] [...] [--view view_name]"
    exit 1
fi

echo Using view $view
while [ -n "$1" ]; do

file=$(echo /etc/bind/zones/db.$1)

if [ ! -f "$file" ]; then
    echo "File $file not found"
    exit 1
fi

/usr/sbin/rndc freeze $1 IN $view &>/dev/null

serial=$(grep '[0-9]\{10\}' "$file" | head -n 1 | awk '{print $1}')

if [ -z "$serial" ]; then
    echo "Serial not found"
    exit 1
fi

if [ ${#serial} -ne 10 ]; then
    echo "Bad serial $serial should be of length 10"
    exit 1
fi

today=$(date +%Y%m%d)

serial_date=${serial:0:8}
serial_id=$(echo ${serial:8} | sed 's/^0*//')

if [ "$serial_id" = "99" ]; then
    echo "Maximum serial reach for today"
    exit 1
fi

if [ $today = $serial_date ]; then
    new_id=$(printf "%02d" $((serial_id + 1)))
else
   new_id="01"
fi

sed -i "s/$serial/$today$new_id/" "$file"

/usr/sbin/rndc thaw $1 IN $view
echo -n "$1: "
/usr/sbin/rndc reload $1 IN $view

shift
if [[ "$1" = "--view" ]]; then
    shift 2
fi
done