routeros-scripts/dhcp-to-dns.rsc
2024-01-31 23:10:15 +01:00

121 lines
6.1 KiB
Text

#!rsc by RouterOS
# RouterOS script: dhcp-to-dns
# Copyright (c) 2013-2024 Christian Hesse <mail@eworm.de>
# https://git.eworm.de/cgit/routeros-scripts/about/COPYING.md
#
# provides: lease-script, order=20
# requires RouterOS, version=7.12
#
# check DHCP leases and add/remove/update DNS entries
# https://git.eworm.de/cgit/routeros-scripts/about/doc/dhcp-to-dns.md
:local 0 [ :jobname ];
:global GlobalFunctionsReady;
:while ($GlobalFunctionsReady != true) do={ :delay 500ms; }
:global Domain;
:global Identity;
:global CleanName;
:global EitherOr;
:global IfThenElse;
:global LogPrintExit2;
:global LogPrintOnce;
:global ParseKeyValueStore;
:global ScriptLock;
$ScriptLock $0 false 10;
:local Ttl 5m;
:local CommentPrefix ("managed by " . $0);
:local CommentString ("--- " . $0 . " above ---");
:if ([ :len [ /ip/dns/static/find where (name=$CommentString or (comment=$CommentString and name=-)) type=NXDOMAIN disabled ] ] = 0) do={
/ip/dns/static/add name=$CommentString type=NXDOMAIN disabled=yes;
$LogPrintExit2 warning $0 ("Added disabled static dns record with name '" . $CommentString . "'.") false;
}
:local PlaceBefore ([ /ip/dns/static/find where (name=$CommentString or (comment=$CommentString and name=-)) type=NXDOMAIN disabled ]->0);
:foreach DnsRecord in=[ /ip/dns/static/find where comment~("^" . $CommentPrefix . "\\b") (!type or type=A) ] do={
:local DnsRecordVal [ /ip/dns/static/get $DnsRecord ];
:local DnsRecordInfo [ $ParseKeyValueStore ($DnsRecordVal->"comment") ];
:local MacInServer ($DnsRecordInfo->"macaddress" . " in " . $DnsRecordInfo->"server");
:if ([ :len [ /ip/dhcp-server/lease/find where active-mac-address=($DnsRecordInfo->"macaddress") \
active-address=($DnsRecordVal->"address") server=($DnsRecordInfo->"server") status=bound ] ] > 0) do={
$LogPrintExit2 debug $0 ("Lease for " . $MacInServer . " (" . $DnsRecordVal->"name" . ") still exists. Not deleting record.") false;
} else={
:local Found false;
$LogPrintExit2 info $0 ("Lease expired for " . $MacInServer . ", deleting record (" . $DnsRecordVal->"name" . ").") false;
/ip/dns/static/remove $DnsRecord;
/ip/dns/static/remove [ find where type=CNAME comment=($DnsRecordVal->"comment") ];
}
}
:foreach Lease in=[ /ip/dhcp-server/lease/find where status=bound ] do={
:local LeaseVal;
:do {
:set LeaseVal [ /ip/dhcp-server/lease/get $Lease ];
:if ([ :len [ /ip/dhcp-server/lease/find where active-mac-address=($LeaseVal->"active-mac-address") status=bound ] ] > 1) do={
$LogPrintOnce info $0 ("Multiple bound leases found for mac-address " . ($LeaseVal->"active-mac-address") . "!") false;
}
} on-error={
$LogPrintExit2 debug $0 ("A lease just vanished, ignoring.") false;
}
:if ([ :len ($LeaseVal->"active-address") ] > 0) do={
:local Comment ($CommentPrefix . ", macaddress=" . $LeaseVal->"active-mac-address" . ", server=" . $LeaseVal->"server");
:local MacDash [ $CleanName ($LeaseVal->"active-mac-address") ];
:local HostName [ $CleanName [ $EitherOr ([ $ParseKeyValueStore ($LeaseVal->"comment") ]->"hostname") ($LeaseVal->"host-name") ] ];
:local Network [ /ip/dhcp-server/network/find where ($LeaseVal->"active-address") in address ];
:local NetworkVal;
:if ([ :len $Network ] > 0) do={
:set NetworkVal [ /ip/dhcp-server/network/get ($Network->0) ];
}
:local NetworkInfo [ $ParseKeyValueStore ($NetworkVal->"comment") ];
:local NetDomain ([ $IfThenElse ([ :len ($NetworkInfo->"name-extra") ] > 0) ($NetworkInfo->"name-extra" . ".") ] . \
[ $EitherOr [ $EitherOr ($NetworkInfo->"domain") ($NetworkVal->"domain") ] $Domain ]);
:local FullA ($MacDash . "." . $NetDomain);
:local FullCN ($HostName . "." . $NetDomain);
:local MacInServer ($LeaseVal->"active-mac-address" . " in " . $LeaseVal->"server");
:local DnsRecord [ /ip/dns/static/find where comment=$Comment (!type or type=A) ];
:if ([ :len $DnsRecord ] > 0) do={
:local DnsRecordVal [ /ip/dns/static/get $DnsRecord ];
:if ($DnsRecordVal->"address" = $LeaseVal->"active-address" && $DnsRecordVal->"name" = $FullA) do={
$LogPrintExit2 debug $0 ("The A record for " . $MacInServer . " (" . $FullA . ") does not need updating.") false;
} else={
$LogPrintExit2 info $0 ("Updating A record for " . $MacInServer . " (" . $FullA . " -> " . $LeaseVal->"active-address" . ").") false;
/ip/dns/static/set address=($LeaseVal->"active-address") name=$FullA $DnsRecord;
}
:local CName [ /ip/dns/static/find where comment=$Comment type=CNAME ];
:if ([ :len $CName ] > 0) do={
:local CNameVal [ /ip/dns/static/get $CName ];
:if ($CNameVal->"name" != $FullCN || $CNameVal->"cname" != $FullA) do={
$LogPrintExit2 info $0 ("Deleting CNAME record with wrong data for " . $MacInServer . ".") false;
/ip/dns/static/remove $CName;
}
}
:if ([ :len $HostName ] > 0 && [ :len [ /ip/dns/static/find where name=$FullCN type=CNAME ] ] = 0) do={
$LogPrintExit2 info $0 ("Adding CNAME record for " . $MacInServer . " (" . $FullCN . " -> " . $FullA . ").") false;
/ip/dns/static/add name=$FullCN type=CNAME cname=$FullA ttl=$Ttl comment=$Comment place-before=$PlaceBefore;
}
} else={
$LogPrintExit2 info $0 ("Adding A record for " . $MacInServer . " (" . $FullA . " -> " . $LeaseVal->"active-address" . ").") false;
/ip/dns/static/add name=$FullA type=A address=($LeaseVal->"active-address") ttl=$Ttl comment=$Comment place-before=$PlaceBefore;
:if ([ :len $HostName ] > 0 && [ :len [ /ip/dns/static/find where name=$FullCN type=CNAME ] ] = 0) do={
$LogPrintExit2 info $0 ("Adding CNAME record for " . $MacInServer . " (" . $FullCN . " -> " . $FullA . ").") false;
/ip/dns/static/add name=$FullCN type=CNAME cname=$FullA ttl=$Ttl comment=$Comment place-before=$PlaceBefore;
}
}
:if ([ :len [ /ip/dns/static/find where name=$FullA (!type or type=A) ] ] > 1) do={
$LogPrintOnce warning $0 ("The name '" . $FullA . "' appeared in more than one A record!") false;
}
} else={
$LogPrintExit2 debug $0 ("No address available... Ignoring.") false;
}
}