diff --git a/clean.pl b/clean.pl
index 6fab844..24d5916 100755
--- a/clean.pl
+++ b/clean.pl
@@ -1,5 +1,19 @@
 #!/usr/bin/env perl
 #
+# Copyright (c) 2023 Mischa Peters <mischa @ openbsd.amsterdam>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
 use 5.024;
 use strict;
 use warnings;
diff --git a/parse.pl b/parse.pl
index 36b4792..da283d3 100755
--- a/parse.pl
+++ b/parse.pl
@@ -1,5 +1,19 @@
 #!/usr/bin/env perl
 #
+# Copyright (c) 2023 Mischa Peters <mischa @ openbsd.amsterdam>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
 use 5.024;
 use strict;
 use warnings;
diff --git a/ptrd.pl b/ptrd.pl
index d0ce4c0..abb30c7 100755
--- a/ptrd.pl
+++ b/ptrd.pl
@@ -1,5 +1,19 @@
 #!/usr/bin/perl
 #
+# Copyright (c) 2023 Mischa Peters <mischa @ openbsd.amsterdam>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
 use 5.024;
 use strict;
 use warnings;
diff --git a/reset.pl b/reset.pl
new file mode 100755
index 0000000..3164208
--- /dev/null
+++ b/reset.pl
@@ -0,0 +1,115 @@
+#!/usr/bin/env perl
+#
+# Copyright (c) 2023 Mischa Peters <mischa @ openbsd.amsterdam>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
+use 5.024;
+use strict;
+use warnings;
+use autodie;
+use Fcntl qw(:flock);
+use File::Basename;
+use File::Copy;
+use POSIX qw(strftime);
+use Net::IP;
+
+my $ipv4_range = new Net::IP("46.23.80.0/20");
+my $ipv6_range = new Net::IP("2a03:6000::/29");
+my $nsd = "/var/nsd/zones/reverse";
+my $v6_zone = "2a03.6000";
+my $default_ptr = "powered-by.openbsd.amsterdam";
+my $workdir = dirname($0);
+my $serial;
+my $serial_prev;
+my $zonefile;
+my $match;
+my $replace;
+
+if (! $ARGV[0]) {
+        print STDERR "usage: $0 <IPv4 | IPv6>\n";
+        exit 1;
+}
+my $client_ip = $ARGV[0];
+my $ip = new Net::IP($client_ip);
+
+if ($ip->overlaps($ipv4_range)) {
+	($zonefile = $client_ip) =~ s/^((\d{1,3}\.){3})\d+$/${1}0/;
+	$match = substr($client_ip, rindex($client_ip, '.')+1);
+
+} elsif ($ip->overlaps($ipv6_range)) {
+	$zonefile = $v6_zone;
+	$match = substr($ip->reverse_ip(), 0, 47);
+}
+$replace = "${match}\t\tIN\tPTR\t${default_ptr}.";
+
+if (qx(rlog ${nsd}/${zonefile} | grep 'locked by') =~ m/locked by/) {
+	_log("$client_ip zone file locked, trying again later...");
+	next;
+} else {
+	open my $fh_in, '<', "${nsd}/$zonefile";
+	open my $fh_out, '>', "${workdir}/zonefiles/$zonefile";
+	while (my $row = <$fh_in>) {
+		chomp $row; 
+		if ($row =~ m/^\s*(\d+)\s*; serial$/) {
+			$serial = $serial_prev = $1;
+			my $timestamp = strftime ("%Y%m%d", localtime()) . "01";
+			if ($serial < $timestamp) {
+				$serial = $timestamp;
+			} else {
+				$serial++;
+			}
+			$row =~ s/${serial_prev}/${serial}/;
+		}
+
+		if ($row =~ m/^${match}\s+IN\s+PTR\s+\S+( ;.*)?$/) {
+			if ($1) {
+				my $comment = $1;
+				$row =~ s/^${match}\s+.*$/${replace}${comment}/;
+			} else {
+				$row =~ s/^${match}\s+.*$/${replace}/;
+			}
+		}
+		print $fh_out "$row\n";
+	}
+	close $fh_in;
+	close $fh_out;
+
+	(my $diff = qx(diff ${nsd}/${zonefile} ${workdir}/zonefiles/${zonefile} | wc -l)) =~ s/^\s*(.*?)\s*$/$1/;
+	if ($diff == 8) {
+		_log("$client_ip diff within limits ($diff), $serial_prev -> $serial");
+		copy("${nsd}/${zonefile}", "${workdir}/zonefiles-archive/${zonefile}-${serial}");
+		qx(co -q -l ${nsd}/${zonefile});
+		copy("${workdir}/zonefiles/${zonefile}", "${nsd}/${zonefile}");
+		qx(ci -q -u -m"updated for ${client_ip}" ${nsd}/${zonefile});
+
+		qx(rcctl reload nsd);
+		qx(rdist -f /etc/Distfile) if (-r '/etc/Distfile');
+
+		my $protect = qx(pfctl -t protected -T delete $client_ip 2>&1);
+		chomp $protect;
+		qx(pfctl -t protected -T show > /etc/pf.protected);
+		_log("$client_ip protected $protect");
+
+	} else {
+		_log("$client_ip diff is outside limits ($diff)");
+	}
+}
+
+sub _log {
+	my ($msg) = @_;
+	open my $fh, '>>', '/var/log/ptrd.log';
+	flock $fh, LOCK_EX;
+	print $fh sprintf("%s %s: %s \n", strftime("%b %d %H:%M:%S", localtime), basename($0), $msg);
+	close $fh;
+}