Adblock script for OpenWRT

adblockupdater.sh

# Adblock script for OpenWRT
# (c) 2015 by Roy Zuo
#
# This is another adblocker script for OpenWRT. Simply run this script as a
# daily cronjob on your OpenWRT-router. This works since OpenWRT
# revision 39312 [1] and does not manipulate any files in /etc/.
# Instead, this adds the adblock serverlist as a separate file
# to /tmp/.
#
# Use this file with Unbound DNS resolver.
#
# [1] See https://dev.openwrt.org/changeset/39312/

# URL for latest block list
srcurl="http://pgl.yoyo.org/adservers/serverlist.php?hostformat=one-line&showintro=0&mimetype=plaintext"

# Set destination file
dstfile="/tmp/unbound_adblock.conf"

# And here comes the magic...
_tmpfile=$(mktemp -tu)
wget -O "$_tmpfile" "$srcurl"

if [[ "$?" -eq 0 ]]; then

    # Write the destination file header
    echo "#" > "$dstfile"
    echo "# $dstfile: adblock server list for Unbound" >> "$dstfile"
    echo "# " >> "$dstfile"
    echo "" >> "$dstfile"
    echo "# Downloaded from URL:" >> "$dstfile"
    echo "# $srcurl" >> "$dstfile"
    echo "# " >> "$dstfile"
    echo "# Last updated: $(date)" >> "$dstfile"
    echo "" >> "$dstfile"

    # Add the servers to the destination file
    for l in $(awk -F, 'END {for(i=1;i<NF;i++) {print $i}}' $_tmpfile); do
        echo "local-data: \"$l A 127.0.0.2\"" >> "$dstfile"
    done

    echo "Everything fine, restarting unbound to implement new serverlist..."
    /etc/init.d/unbound restart
fi

rm "$_tmpfile"