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Author SHA1 Message Date
Sven Luthi 4d3b01127b Bump to v1.0.7 2026-02-18 15:51:55 +01:00
Sven Luethi 997f36264a modified: src/netbox_plugin_bind_provisioner/__init__.py
Bumping version to v1.0.6
2026-02-09 16:54:17 +01:00
Sven Luethi 19a946c880 - Split bind transfer command into multiple files for better code readability.
- Rename bind-transfer-endpoint command -> dns-transfer-endpoint.
2026-02-05 12:27:28 +01:00
Sven Luethi 9afdfe869b - Store catz member zone identifiers in database, linked to the corresponding zone object.
- Catz member identifiers are created from uuid encoded in base32, lower-cased, and padding removed.
- On endpoint startup, make sure all zones have a catz identifier assigned. If not, create them.
- Use signals to create or update a zone's catz identifier.
2026-02-05 12:26:55 +01:00
Sven Luethi 1fae3bfe54 Adds back the changes made to support ipv6 in commit 8fba131230 but that were reverted with commit ca51a6054d to allow proper merging of another complex PR. Closes #11 again
Also includes a small bug fix that was added with commit 6bbb2e9905 but that was also temporarily reverted with 45f9631a98.
2026-01-31 09:43:19 +01:00
Sven Luethi 562f54d481 Merge pull request #12 from spamik/support-tcp-soa
Support SOA request on TCP by merging the dns handling while leaving the transport handling in protocol specific handlers (partially). Further review pending
2026-01-31 09:08:42 +01:00
Sven Luethi ca51a6054d This reverts commit 8fba131230. 2026-01-31 09:01:04 +01:00
Sven Luethi 45f9631a98 This reverts commit 6bbb2e9905. 2026-01-31 09:00:44 +01:00
spm 0d041a0830 Handle more DNS requests via one TCP connection 2026-01-29 15:58:32 +01:00
Sven Luethi 6bbb2e9905 modified: src/netbox_plugin_bind_provisioner/management/commands/bind-transfer-endpoint.py
Catches a further exception if the wrong algorithm is specified for the tsig key used.
2026-01-29 11:11:49 +01:00
Sven Luethi 8fba131230 modified: src/netbox_plugin_bind_provisioner/management/commands/bind-transfer-endpoint.py
Fixes issue #11 (IPv6 support)
2026-01-29 11:10:31 +01:00
spm a9dbbe8c88 Support SOA request on TCP
- unified handling of DNS queries on TCP and UDP channels
- as a result it now responds on SOA requests over TCP
2026-01-28 17:35:58 +01:00
14 changed files with 942 additions and 733 deletions

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+4 -4
View File
@@ -26,13 +26,13 @@ under the special zone name **"catz"** and addtionally under **"[viewname].catz"
and may be queried through the built-in DNS server just like any other dns zone. and may be queried through the built-in DNS server just like any other dns zone.
For proper operation, each view requires an installed TSIG key, and the For proper operation, each view requires an installed TSIG key, and the
`bind-transfer-endpoint` must be running as a separate background service using `dns-transfer-endpoint` must be running as a separate background service using
the `manage.py` command. Note that DNSSEC support will be added once BIND9 the `manage.py` command. Note that DNSSEC support will be added once BIND9
provides a mechanism to configure it through the Catalog Zones system. provides a mechanism to configure it through the Catalog Zones system.
To start the service in the foreground: To start the service in the foreground:
``` ```
manage.py bind-transfer-endpoint --port 5354 manage.py dns-transfer-endpoint --port 5354
``` ```
This process needs to be scheduled as a background service for the built-in DNS This process needs to be scheduled as a background service for the built-in DNS
Server to work correctly. For Linux users with Systemd (Ubuntu, etc), Matt Kollross Server to work correctly. For Linux users with Systemd (Ubuntu, etc), Matt Kollross
@@ -135,10 +135,10 @@ This guide assumes:
Note that `--port 5354` is optional. The listener will bind this port Note that `--port 5354` is optional. The listener will bind this port
by default. by default.
``` ```
python3 netbox/manage.py bind-transfer-endpoint --port 5354 python3 netbox/manage.py dns-transfer-endpoint --port 5354
``` ```
6. Configuring a Bind9 to interact with Netbox via the bind-transfer-endpoint 6. Configuring a Bind9 to interact with Netbox via the dns-transfer-endpoint
endpoint. Note that its not possible to give all the correct details of the endpoint. Note that its not possible to give all the correct details of the
`options` block as it is heavily dependent on the Operating System used. `options` block as it is heavily dependent on the Operating System used.
Please dont forget to adjust as required. Please dont forget to adjust as required.
+1 -1
View File
@@ -15,7 +15,7 @@
PIDFile=/var/tmp/netbox.pid PIDFile=/var/tmp/netbox.pid
WorkingDirectory=/opt/netbox WorkingDirectory=/opt/netbox
ExecStart=/opt/netbox/venv/bin/python3 /opt/netbox/netbox/manage.py bind-transfer-endpoint --port 5354 ExecStart=/opt/netbox/venv/bin/python3 /opt/netbox/netbox/manage.py dns-transfer-endpoint --port 5354
Restart=on-failure Restart=on-failure
RestartSec=30 RestartSec=30
@@ -1,11 +1,8 @@
import logging import logging
from netbox.plugins import PluginConfig from netbox.plugins import PluginConfig
from django.db import models
from django.utils.translation import gettext_lazy as _
from django.dispatch import receiver
from django.conf import settings from django.conf import settings
__version__ = "1.0.5" __version__ = "1.0.7"
logger = logging.getLogger(__name__) logger = logging.getLogger(__name__)
@@ -32,6 +29,8 @@ class BindProvisionerConfig(PluginConfig):
f"{self.name}: Plugin {self.verbose_name} failed to initialize due to missing settings. Terminating Netbox." f"{self.name}: Plugin {self.verbose_name} failed to initialize due to missing settings. Terminating Netbox."
) )
from . import signals as signals
config = BindProvisionerConfig config = BindProvisionerConfig
default_app_config = ".apps.NetboxBindProvisionerConfig" default_app_config = ".apps.NetboxBindProvisionerConfig"
@@ -1,724 +0,0 @@
import logging
import socketserver
import os
import threading
import dns.query
import dns.message
import dns.tsigkeyring
import dns.name
import dns.zone
import dns.rdatatype
import dns.rdataclass
import dns.rdtypes
import dns.exception
import dns.renderer
from django.core.management.base import BaseCommand
from django.conf import settings
from django.utils import timezone
from netbox_dns.models import Zone, Record, View
from netbox_dns.choices import ZoneStatusChoices, RecordStatusChoices
from datetime import datetime
from netbox_plugin_bind_provisioner.models import IntegerKeyValueSetting
logger = logging.getLogger("bind-transfer-endpoint")
class CatalogZone:
lock = threading.Lock()
_serial_max = 0xFFFFFFFF
_serial_obj = None
_previous_last_zone_update = None
# Following function loads the last serial from the DB. No return value
# but it sets the setting "catalog_serial" or terminates the plugin on failure.
@classmethod
def initSerial(cls):
try:
cls._serial_obj = IntegerKeyValueSetting.objects.get(
key="catalog-zone-soa-serial"
)
logger.debug(
f"Catalog zone SOA serial number {cls._serial_obj.value} loaded from database"
)
except IntegerKeyValueSetting.DoesNotExist:
cls._serial_obj = IntegerKeyValueSetting.objects.create(
key="catalog-zone-soa-serial", value=1
)
logger.debug(
f"Catalog zone SOA serial number was not set in the database. Set to {cls._serial_obj.value}"
)
@classmethod
def _incrementSerial(cls):
if 0 < cls._serial_obj.value < cls._serial_max:
cls._serial_obj.value += 1
cls._serial_obj.save()
else:
logger.warn(
f"Failed to incremenet catalog serial {cls._serial_obj.value}. Will overflow serial back to 1"
)
cls._serial_obj = 1
cls._serial_obj.save()
logger.debug(
f"Catalog zone SOA serial number incremented to {_serial_obj.value}"
)
@classmethod
def create(cls, name, view_name):
# Synchronize following across threads as TCP and UDP listener both use it.
with cls.lock:
# cls = self.__class__
# datestamp = datetime.now().strftime("%y%m%d")
# latest_zone = Zone.objects.filter().order_by("-last_updated").first()
latest_zone = (
Zone.objects.filter(status=ZoneStatusChoices.STATUS_ACTIVE)
.order_by("-last_updated")
.first()
)
last_zone_update = getattr(latest_zone, "last_updated", None)
# Check if there was a zone updated since last call
# If no zone was found previously then this will be false since (None != None) = False
if cls._previous_last_zone_update != last_zone_update:
if last_zone_update is not None:
logger.debug(
f"Zone {latest_zone.name} was updated in view {latest_zone.view.name}"
)
# Setting previous last zone update for next iteration:
cls._previous_last_zone_update = last_zone_update
cls._incrementSerial()
# Zone origin
origin = dns.name.from_text(name, dns.name.root)
# Create a new empty zone
zone = dns.zone.Zone(origin)
zone.rdclass = dns.rdataclass.IN
# get zones from netbox
nb_zones = Zone.objects.filter(
view__name=view_name, status=ZoneStatusChoices.STATUS_ACTIVE
)
ptr_base = dns.name.from_text("zones", origin)
for nb_zone in nb_zones:
ttl = 0
qname = dns.name.from_text(nb_zone.name, dns.name.root)
# Create PTR record
p_name = f"zid-{nb_zone.id:09d}"
ptr_name = dns.name.from_text(p_name, ptr_base)
assert ptr_name.is_subdomain(origin)
rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.PTR, qname.to_text()
)
rdataset = zone.find_rdataset(ptr_name, dns.rdatatype.PTR, create=True)
rdataset.add(rdata, ttl)
# Configure DNSSec Policy for member Zone if DNSSec is enabled
if nb_zone.dnssec_policy:
# Configure policy
rid = dns.name.from_text("group", ptr_name)
policy_name = nb_zone.dnssec_policy.name.rstrip(" ")
group_name = f"dnssec-policy-{policy_name}"
rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.TXT, group_name
)
rdataset = zone.find_rdataset(rid, dns.rdatatype.TXT, create=True)
rdataset.add(rdata, ttl)
## Configure dnssec status for member zone
# status = str(1 if nb_zone.dnssec_policy else 0)
# rid = dns.name.from_text("enabled.dnssec.ext", ptr_name)
# rdata = dns.rdata.from_text(dns.rdataclass.IN, dns.rdatatype.TXT, status)
# rdataset = zone.find_rdataset(rid, dns.rdatatype.TXT, create=True)
# rdataset.add(rdata, ttl)
# SOA Record components
ttl = 0
rclass = dns.rdataclass.IN
rtype = dns.rdatatype.SOA
mname = dns.name.from_text("invalid", dns.name.root)
rname = dns.name.from_text("invalid", dns.name.root)
serial = cls._serial_obj.value
refresh = 60
retry = 10
expire = 1209600
minimum = 0
# Create SOA rdata object
soa_rdata = dns.rdata.from_text(
rclass,
rtype,
f"{mname} {rname} {serial} {refresh} {retry} {expire} {minimum}",
)
# Create Rdataset and add the RDATA to it
soa_rdataset = dns.rdataset.Rdataset(rclass, rtype)
soa_rdataset.add(soa_rdata, ttl)
# Add to the origin node in the zone
node = zone.find_node(origin, create=True)
node.rdatasets.append(soa_rdataset)
# NS record for catz.
ns_name = dns.name.from_text("invalid", dns.name.root)
ns_rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.NS, str(ns_name)
)
ns_rdataset = dns.rdataset.Rdataset(dns.rdataclass.IN, dns.rdatatype.NS)
ns_rdataset.add(ns_rdata, 0)
# Add to node (catz. is the origin)
ns_node = zone.find_node(origin, create=True)
ns_node.rdatasets.append(ns_rdataset)
# TXT record for version.catz.
version_name = dns.name.from_text(
"version", origin
) # relative to origin "catz."
txt_rdata = dns.rdata.from_text(dns.rdataclass.IN, dns.rdatatype.TXT, '"2"')
txt_rdataset = dns.rdataset.Rdataset(dns.rdataclass.IN, dns.rdatatype.TXT)
txt_rdataset.add(txt_rdata, 0)
# Add to node version.catz.
txt_node = zone.find_node(version_name, create=True)
txt_node.rdatasets.append(txt_rdataset)
return zone
class DNSBaseRequestHandler(socketserver.BaseRequestHandler):
# getZoneFromNB rewritten
def getZoneFromNB(self, zone_name, view_name):
# Find the zone
try:
nb_zone = Zone.objects.get(
name=zone_name,
view__name=view_name,
status=ZoneStatusChoices.STATUS_ACTIVE,
)
except Zone.DoesNotExist:
return None
# Build DNS zone
zone = dns.zone.Zone(zone_name, dns.name.root)
zone.rdclass = dns.rdataclass.IN
nb_records = Record.objects.filter(
zone=nb_zone, status=RecordStatusChoices.STATUS_ACTIVE
)
rdatasets_dict = {}
for record in nb_records:
rdtype = dns.rdatatype.from_text(record.type)
if not record.name:
name = zone.origin
elif record.name.endswith("."):
name = dns.name.from_text(record.name)
else:
name = dns.name.from_text(record.name, origin=zone.origin)
# If the record has no TTL, use the zone default
ttl = record.ttl or nb_zone.default_ttl
# Apply quoting for TXT records to stop tokanizer
# from cutting it up:
value = record.value
if rdtype == dns.rdatatype.TXT:
if value.startswith('"') and value.endswith('"'):
value = value[1:-1].replace('" "', "").replace('"', '"')
if len(value) > 255:
# This is a bug fix for netbox. If netbox allowed for
# an unquoted value to be larger then 255 characters,
# it misunderstood everything behind a ; as a comment.
chunks = [
'"{}"'.format(value[i : i + 255])
for i in range(0, len(value), 255)
]
value = " ".join(chunks)
else:
value = f'"{value}"'
rdata = dns.rdata.from_text(
dns.rdataclass.IN,
rdtype,
value,
relativize=False,
origin=zone.origin,
)
# Initialize rdataset if it doesn't exist for this name and type
if name not in rdatasets_dict:
rdatasets_dict[name] = {}
if rdtype not in rdatasets_dict[name]:
rdatasets_dict[name][rdtype] = dns.rdataset.Rdataset(
dns.rdataclass.IN, rdtype
)
# Add the rdata to the appropriate rdataset
rdatasets_dict[name][rdtype].add(rdata, ttl)
# Now, add all rdatasets to the zone
for name, rdtypes in rdatasets_dict.items():
for rdtype, rdataset in rdtypes.items():
# Ensure rdataset has the same rdclass as the zone
if rdataset.rdclass != zone.rdclass:
raise ValueError(
f"rdataset rdclass {rdataset.rdclass} does not match zone rdclass {zone.rdclass}"
)
# Check if the rdataset has any rdata before creating an RRset
if not rdataset:
logger.debug(f"Skipping empty rdataset for {name} {rdtype}")
continue # Skip empty rdataset
# Replace the rdataset for the given name and type
zone.replace_rdataset(name, rdataset)
return zone
def denyRequestBadTSIG(self, wire, tsig_error: dns.rcode):
# Use empty keyring to parse TSIG without validating
query = dns.message.from_wire(
wire, keyring={}, ignore_trailing=True, continue_on_error=True
)
# Make a response
response = dns.message.make_response(query)
response.set_rcode(dns.rcode.REFUSED)
if query.had_tsig:
# Add TSIG with BADKEY, but do not sign (no MAC)
response.use_tsig(
keyring={}, # empty; we're not signing
keyname=query.keyname,
tsig_error=tsig_error,
)
self.denyRequest(query)
class UDPRequestHandler(DNSBaseRequestHandler):
def denyRequest(self, query, rcode: dns.rcode = dns.rcode.REFUSED):
response = dns.message.make_response(query)
response.set_rcode(rcode)
wire = response.to_wire(multi=False)
sock = self.request[1]
sock.sendto(wire, self.client_address)
def handle(self):
data, sock = self.request
peer = self.client_address[0]
query = None
try:
query = dns.message.from_wire(
data,
keyring=self.server.keyring,
continue_on_error=False,
ignore_trailing=True,
)
except Exception as e:
logger.error("Error parsing query: ", e)
return
# Create a response
response = dns.message.make_response(query)
# Set the Authoritative Answer flag
response.flags |= dns.flags.AA
question = query.question[0]
# Get the queried record name and type:
qname = question.name
qtype = question.rdtype
dname = qname.to_text().rstrip(".")
# Only process SOA queries
if qtype != dns.rdatatype.SOA:
logger.warning(
f"Request denied from {peer}: Request was not SOA (Type: {qtype})"
)
self.denyRequest(query)
return
# Identify TSIG key used
if not query.had_tsig:
logger.warning(f"Request denied from {peer}: No TSIG key used")
self.denyRequest(query)
return
key_name = query.keyname.canonicalize().to_text()
# Check if key matches a view
nb_view = self.server.tsig_view_map.get(key_name)
if not nb_view:
logger.warning(
f"Request denied from {peer}: {key_name} does not match a view"
)
self.denyRequestBadTSIG(wire, dns.rcode.BADKEY)
return
# Check if catalog zone
if dname == "catz" or dname == f"{nb_view.name}.catz":
zone = CatalogZone.create(dname, nb_view.name)
# If generic zone, retreive from NB
else:
zone = self.getZoneFromNB(dname, nb_view.name)
# When zone was not found, let client know
if not zone:
logger.warning(f"Zone {nb_view.name}/{dname} not found in NB")
self.denyRequest(query)
return
# Retrieve the existing SOA record from the Zone
soa_rdataset = zone.get_rdataset(zone.origin, dns.rdatatype.SOA)
# We assume that the SOA rdataset has at least one record (it usually does).
soa_rdata = soa_rdataset[0] # Get the first SOA record
# Now, create the rrset from the soa_rdata
rrset = dns.rrset.from_rdata(zone.origin, soa_rdataset.ttl, soa_rdata)
# Append the rrset to the response's answer section
response.answer.append(rrset)
# TSIG response
if query.had_tsig:
# If key was found in DB
if query.keyname in self.server.keyring:
response.use_tsig(
self.server.keyring, keyname=query.keyname, original_id=query.id
)
else:
# If key is unknown
response.set_rcode(dns.rcode.REFUSED)
# Generate new key for keyname provided
# keyname = query.keyname
# b64 = base64.b64encode(urandom(32)).decode("ascii")
# newkey = dns.tsigkeyring.from_text({ keyname: b64 })
response.use_tsig(
self.server.keyring,
keyname=query.keyname,
tsig_error=dns.rcode.BADKEY,
)
# Send back the response
response_wire = response.to_wire(max_size=512)
sock.sendto(response_wire, self.client_address)
logger.debug(f"{peer} SOA {nb_view.name}/{dname}")
class TCPRequestHandler(DNSBaseRequestHandler):
def denyRequest(self, query, rcode: dns.rcode = dns.rcode.REFUSED):
response = dns.message.make_response(query)
response.set_rcode(rcode)
wire = response.to_wire(multi=False)
length = len(wire).to_bytes(2, byteorder="big")
self.request.sendall(length + wire)
def handle(self):
MAX_WIRE = 65535
# MAX_WIRE = 2000 # For testing fragmentation
RESERVED_TSIG = 300
# create a var for setting the client ip in log messages
peer = self.client_address[0]
try:
# Receive the entire message....
sock = self.request # TCP socket
# Read 2-byte length prefix
length_data = sock.recv(2)
if len(length_data) < 2:
return
length = int.from_bytes(length_data, byteorder="big")
wire = b""
while len(wire) < length:
chunk = sock.recv(length - len(wire))
if not chunk:
return # connection closed
wire += chunk
# Parse the query
query = None
try:
query = dns.message.from_wire(wire, keyring=self.server.keyring)
# If TSIG signature doesnt match our key, refuse query:
except dns.tsig.BadSignature as e:
logger.warning(
f"Request denied from {peer} failed TSIG verification: {e}"
)
self.denyRequestBadTSIG(wire, dns.rcode.BADSIG)
return
# If TSIG Key used is not in our list, refuse query:
except dns.message.UnknownTSIGKey as e:
logger.warning(f"Request denied from {peer} with bad TSIG key: {e}")
self.denyRequestBadTSIG(wire, dns.rcode.BADKEY)
return
# If there was no question in the query, refuse
if len(query.question) != 1:
self.denyRequest(query)
return
# Get the queried record name and type:
qname = query.question[0].name
qtype = query.question[0].rdtype
dname = qname.to_text().rstrip(".")
# Only process AXFR queries
if qtype != dns.rdatatype.AXFR:
# if qtype != dns.rdatatype.AXFR or qtype != dns.rdatatype.SOA:
logger.warning(
f"Request denied from {peer}: Request was not AXFR (Type: {qtype})"
)
self.denyRequest(query)
return
# Identify TSIG key used
if not query.had_tsig:
logger.warning(f"Request denied from {peer}: No TSIG key used")
self.denyRequest(query)
return
key_name = query.keyname.canonicalize().to_text()
# Check if the key matches a view
nb_view = self.server.tsig_view_map.get(key_name)
if not nb_view:
logger.warning(
f"Request denied from {peer}: {key_name} does not match a view"
)
self.denyRequest(query)
return
# Check if catalog zone
if dname == "catz" or dname == f"{nb_view.name}.catz":
zone = CatalogZone.create(dname, nb_view.name)
else:
zone = self.getZoneFromNB(dname, nb_view.name)
# When zone was not found, let client know
if not zone:
logger.warning(f"Zone {dname} not found in view {nb_view.name}")
self.denyRequest(query)
return
# 1. Prepare SOA + RRsets (identical to your code)
soa_rrset = None
rrsets = []
for name, rdataset in zone.iterate_rdatasets():
if not name.is_absolute():
name = name.concatenate(zone.origin)
rrset = dns.rrset.from_rdata_list(name, rdataset.ttl, rdataset)
if rdataset.rdtype == dns.rdatatype.SOA and soa_rrset is None:
soa_rrset = rrset
else:
rrsets.append(rrset)
if soa_rrset is None:
logger.error(f"Zone {dname} has no SOA — aborting AXFR")
return
rrsets.insert(0, soa_rrset) # Opening SOA
rrsets.append(soa_rrset) # Closing SOA
# 2. Create a Renderer for the first message
r = dns.renderer.Renderer(
id=query.id,
flags=(dns.flags.QR | dns.flags.AA),
max_size=MAX_WIRE,
origin=None,
)
r.add_question(
query.question[0].name,
query.question[0].rdtype,
query.question[0].rdclass,
)
# 3. Loop through RRsets
tsig_ctx = None
for rrset in rrsets:
# logger.debug(f"Iterating over rrset {rrset}. tsig_ctx: {tsig_ctx}")
try:
# logger.debug(f"Adding {rrset} to renderer object")
r.add_rrset(dns.renderer.ANSWER, rrset)
if r.max_size - len(r.output.getvalue()) < RESERVED_TSIG:
raise dns.exception.TooBig("TSIG wont fit")
except dns.exception.TooBig:
# TSIG chain previous message
r.write_header()
tsig_ctx = r.add_multi_tsig(
ctx=tsig_ctx,
secret=self.server.keyring[query.keyname],
keyname=query.keyname,
fudge=300,
id=query.id,
tsig_error=0,
other_data=b"",
request_mac=r.mac if tsig_ctx else query.mac,
)
wire = r.get_wire()
self.request.sendall(len(wire).to_bytes(2, "big") + wire)
# Start new renderer
r = dns.renderer.Renderer(
id=query.id,
flags=(dns.flags.QR | dns.flags.AA),
max_size=MAX_WIRE,
origin=None,
)
r.add_question(
query.question[0].name,
query.question[0].rdtype,
query.question[0].rdclass,
)
r.add_rrset(dns.renderer.ANSWER, rrset)
# 4. Final message with terminating TSIG
r.write_header()
# logger.debug(f"Final message. tsig_ctx: {tsig_ctx}")
tsig_ctx = r.add_multi_tsig(
ctx=tsig_ctx,
secret=self.server.keyring[query.keyname],
keyname=query.keyname,
fudge=300,
id=query.id,
tsig_error=0,
other_data=b"",
# request_mac=r.mac if tsig_ctx else None,
request_mac=r.mac if tsig_ctx else query.mac,
)
wire = r.get_wire()
self.request.sendall(len(wire).to_bytes(2, "big") + wire)
# logger.debug(f"Zone transfer request for {nb_view.name}/{dname} from {peer}")
logger.debug(f"{peer} AXFR {nb_view.name}/{dname}")
except Exception as e:
logger.error(f"Error handling request from {peer}: {e}")
import traceback
traceback.print_exc()
class TCPDNSServer(socketserver.TCPServer):
allow_reuse_address = True
def __init__(self, server_address, handler_class, keyring, tsig_view_map):
super().__init__(server_address, handler_class)
self.keyring = keyring
self.tsig_view_map = tsig_view_map
class UDPDNSServer(socketserver.UDPServer):
allow_reuse_address = True
def __init__(self, server_address, handler_class, keyring, tsig_view_map):
super().__init__(server_address, handler_class)
self.keyring = keyring
self.tsig_view_map = tsig_view_map
class Command(BaseCommand):
help = "Run a minimal AXFR DNS server using NetBox DNS plugin data"
def loadSettings(self):
self.settings = settings.PLUGINS_CONFIG.get(
"netbox_plugin_bind_provisioner", None
)
if not self.settings:
raise RuntimeError(
"Command failed to initialize due to missing settings. Terminating Netbox."
)
self.tsig_keys = self.settings.get("tsig_keys", None)
if not self.tsig_keys:
raise RuntimeError("tsig_keys variable not set in plugin settings.")
# Load TSIG keys and map them to views
def loadTSIGKeySettings(self):
self.keyring = {}
self.tsig_view_map = {}
for view_name, data in self.tsig_keys.items():
raw_key_name = data.get("keyname")
secret = data.get("secret")
algorithm_str = data.get("algorithm", "hmac-sha256")
if not raw_key_name or not secret:
logger.error(
f"Skipping TSIG key for view {view_name}: missing keyname or secret."
)
continue
try:
nb_view = View.objects.get(name=view_name)
except View.DoesNotExist:
logger.error(
f"Skipping TSIG key {raw_key_name}: view '{view_name}' not found."
)
continue
# Normalize key name to absolute DNS name
key_name_obj = dns.name.from_text(raw_key_name, origin=None).canonicalize()
if not key_name_obj.is_absolute():
key_name_obj = key_name_obj.concatenate(dns.name.root)
key_name_str = key_name_obj.to_text() # Will always include trailing do
self.keyring[key_name_obj] = dns.tsig.Key(
name=key_name_obj, secret=secret, algorithm=algorithm_str
)
self.tsig_view_map[key_name_str] = nb_view
logger.debug(f"Loaded TSIG key: {key_name_str} view: {nb_view.name}")
if not self.keyring:
msg = "No TSIG keys found in database."
logger.critical(msg)
raise RuntimeError(msg)
def add_arguments(self, parser):
parser.add_argument(
"--port", type=int, default=5354, help="Port number to listen on"
)
parser.add_argument(
"--address", type=str, default="0.0.0.0", help="IP to bind to"
)
def handle(self, *args, **options):
# Load parameters
port = options["port"]
address = options["address"]
CatalogZone.initSerial()
# Initialize settings
self.loadSettings()
self.loadTSIGKeySettings()
udp_server = UDPDNSServer(
(address, port), UDPRequestHandler, self.keyring, self.tsig_view_map
)
tcp_server = TCPDNSServer(
(address, port), TCPRequestHandler, self.keyring, self.tsig_view_map
)
def run_udp_server(server):
logger.debug(f"SOA endpoint listening on {address} udp/{port}")
server.serve_forever()
udp_thread = threading.Thread(
target=run_udp_server, args=(udp_server,), daemon=True
)
udp_thread.start()
logger.debug(f"AXFR endpoint listening on {address} tcp/{port}")
tcp_server.serve_forever()
@@ -0,0 +1,117 @@
import logging
import threading
import dns.query
import dns.message
import dns.tsigkeyring
import dns.name
import dns.zone
import dns.rdatatype
import dns.rdataclass
import dns.rdtypes
import dns.exception
import dns.renderer
from django.core.management.base import BaseCommand
from django.conf import settings
from netbox_dns.models import View
from netbox_plugin_bind_provisioner.service.endpoint.request_handler import UDPRequestHandler, TCPRequestHandler
from netbox_plugin_bind_provisioner.service.endpoint.dns_server import UDPDNSServer, TCPDNSServer
from netbox_plugin_bind_provisioner.service.endpoint import catalog_zone_manager as catzm
logger = logging.getLogger("dns-transfer-endpoint")
class Command(BaseCommand):
help = "Run a minimal AXFR DNS server using data from NetBox DNS plugin"
def load_settings(self):
self.settings = settings.PLUGINS_CONFIG.get(
"netbox_plugin_bind_provisioner", None
)
if not self.settings:
raise RuntimeError(
"Command failed to initialize due to missing settings. Terminating Netbox."
)
self.tsig_keys = self.settings.get("tsig_keys", None)
if not self.tsig_keys:
raise RuntimeError("tsig_keys variable not set in plugin settings.")
# Load TSIG keys and map them to views
def load_tsig_key_settings(self):
self.keyring = {}
self.tsig_view_map = {}
for view_name, data in self.tsig_keys.items():
raw_key_name = data.get("keyname")
secret = data.get("secret")
algorithm_str = data.get("algorithm", "hmac-sha256")
if not raw_key_name or not secret:
logger.error(
f"Skipping TSIG key for view {view_name}: missing keyname or secret."
)
continue
try:
nb_view = View.objects.get(name=view_name)
except View.DoesNotExist:
logger.error(
f"Skipping TSIG key {raw_key_name}: view '{view_name}' not found."
)
continue
# Normalize key name to absolute DNS name
key_name_obj = dns.name.from_text(raw_key_name, origin=None).canonicalize()
if not key_name_obj.is_absolute():
key_name_obj = key_name_obj.concatenate(dns.name.root)
key_name_str = key_name_obj.to_text() # Will always include trailing do
self.keyring[key_name_obj] = dns.tsig.Key(
name=key_name_obj, secret=secret, algorithm=algorithm_str
)
self.tsig_view_map[key_name_str] = nb_view
logger.debug(f"Loaded TSIG key: {key_name_str} view: {nb_view.name}")
if not self.keyring:
msg = "No TSIG keys found in database."
logger.critical(msg)
raise RuntimeError(msg)
def add_arguments(self, parser):
parser.add_argument(
"--port", type=int, default=5354, help="Port number to listen on"
)
parser.add_argument(
"--address", type=str, default="0.0.0.0", help="IP to bind to"
)
def handle(self, *args, **options):
# Load parameters
port = options["port"]
address = options["address"]
catzm.init()
# Initialize settings
self.load_settings()
self.load_tsig_key_settings()
udp_server = UDPDNSServer(
(address, port), UDPRequestHandler, self.keyring, self.tsig_view_map
)
tcp_server = TCPDNSServer(
(address, port), TCPRequestHandler, self.keyring, self.tsig_view_map
)
def run_udp_server(server):
logger.debug(f"Query endpoint listening on {address} udp/{port}")
server.serve_forever()
udp_thread = threading.Thread(
target=run_udp_server, args=(udp_server,), daemon=True
)
udp_thread.start()
logger.debug(f"Query endpoint listening on {address} tcp/{port}")
tcp_server.serve_forever()
@@ -0,0 +1,26 @@
# Generated by Django 5.2.9 on 2026-02-02 09:23
import django.db.models.deletion
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('netbox_dns', '0030_dnsseckeytemplate_comments_dnsseckeytemplate_owner_and_more'),
('netbox_plugin_bind_provisioner', '0002_alter_integerkeyvaluesetting_options_and_more'),
]
operations = [
migrations.CreateModel(
name='CatalogZoneMemberIdentifier',
fields=[
('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False)),
('name', models.CharField(max_length=26, unique=True)),
('zone', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='bind_provisioner_models', to='netbox_dns.zone')),
],
options={
'ordering': ('name',),
},
),
]
@@ -0,0 +1,20 @@
# Generated by Django 5.2.9 on 2026-02-02 10:53
import django.db.models.deletion
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('netbox_dns', '0030_dnsseckeytemplate_comments_dnsseckeytemplate_owner_and_more'),
('netbox_plugin_bind_provisioner', '0003_catalogzonememberidentifier'),
]
operations = [
migrations.AlterField(
model_name='catalogzonememberidentifier',
name='zone',
field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='bind_provisioner_catz_identifier', to='netbox_dns.zone'),
),
]
@@ -0,0 +1,20 @@
# Generated by Django 5.2.9 on 2026-02-02 20:49
import django.db.models.deletion
from django.db import migrations, models
class Migration(migrations.Migration):
dependencies = [
('netbox_dns', '0030_dnsseckeytemplate_comments_dnsseckeytemplate_owner_and_more'),
('netbox_plugin_bind_provisioner', '0004_alter_catalogzonememberidentifier_zone'),
]
operations = [
migrations.AlterField(
model_name='catalogzonememberidentifier',
name='zone',
field=models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='catz_identifier', to='netbox_dns.zone'),
),
]
@@ -12,3 +12,20 @@ class IntegerKeyValueSetting(models.Model):
class Meta: class Meta:
default_permissions = () default_permissions = ()
class CatalogZoneMemberIdentifier(models.Model):
name = models.CharField(
max_length=26,
unique=True,
)
zone = models.OneToOneField(
to=netbox_dns.models.Zone,
on_delete=models.CASCADE,
related_name="catz_identifier",
)
class Meta:
ordering = ("name",)
def __str__(self):
return self.name
Whitespace-only changes.
@@ -0,0 +1,227 @@
import logging
import threading
import dns.query
import dns.message
import dns.tsigkeyring
import dns.name
import dns.zone
import dns.rdatatype
import dns.rdataclass
import dns.rdtypes
import dns.exception
import dns.renderer
from netbox_dns.models import Zone
from netbox_dns.choices import ZoneStatusChoices
from netbox_plugin_bind_provisioner.models import IntegerKeyValueSetting, CatalogZoneMemberIdentifier
from uuid import uuid4
from base64 import b32encode
logger = logging.getLogger("dns-transfer-endpoint")
_LOCK = threading.Lock()
_SERIAL_MAX = 0xFFFFFFFF
_SERIAL_OBJ = None
_PREVIOUS_LAST_ZONE_UPDATE = None
def init() -> None:
_init_serial()
_create_missing_member_identifiers()
# Following function loads the last serial from the DB. No return value
# but it sets the setting "catalog_serial" or terminates the plugin on failure.
def _init_serial() -> None:
global _SERIAL_OBJ
try:
_SERIAL_OBJ = IntegerKeyValueSetting.objects.get(
key="catalog-zone-soa-serial"
)
logger.debug(
f"Catalog zone SOA serial number {_SERIAL_OBJ.value} loaded from database"
)
except IntegerKeyValueSetting.DoesNotExist:
_SERIAL_OBJ = IntegerKeyValueSetting.objects.create(
key="catalog-zone-soa-serial", value=1
)
logger.debug(
f"Catalog zone SOA serial number was not set in the database. Set to {_SERIAL_OBJ.value}"
)
def _increment_serial() -> None:
global _SERIAL_OBJ
if 0 < _SERIAL_OBJ.value < _SERIAL_MAX:
_SERIAL_OBJ.value += 1
_SERIAL_OBJ.save()
else:
logger.warning(
f"Failed to incremenet catalog serial {_SERIAL_OBJ.value}. Will overflow serial back to 1"
)
_SERIAL_OBJ.value = 1
_SERIAL_OBJ.save()
logger.debug(
f"Catalog zone SOA serial number incremented to {_SERIAL_OBJ.value}"
)
# If a zone has no catz identifier yet, create it:
def _create_missing_member_identifiers() -> None:
existing_zone_ids = CatalogZoneMemberIdentifier.objects.values_list(
"zone_id", flat=True
)
missing_zones = Zone.objects.exclude(id__in=existing_zone_ids)
new_objects = [
CatalogZoneMemberIdentifier(
zone=zone,
name=_generate_member_identifier(),
)
for zone in missing_zones
]
for identifier in new_objects:
logger.debug(f"Zone {identifier.zone} has no catz member identifier. Creating...")
CatalogZoneMemberIdentifier.objects.bulk_create(
new_objects,
ignore_conflicts=False,
)
def create_zone(name, view_name) -> dns.zone.Zone:
global _PREVIOUS_LAST_ZONE_UPDATE
# Synchronize following across threads as TCP and UDP listener both use it.
with _LOCK:
latest_zone = (
Zone.objects.filter(status=ZoneStatusChoices.STATUS_ACTIVE)
.order_by("-last_updated")
.first()
)
last_zone_update = getattr(latest_zone, "last_updated", None)
# Check if there was a zone updated since last call
# If no zone was found previously then this will be false since (None != None) = False
if _PREVIOUS_LAST_ZONE_UPDATE != last_zone_update:
if last_zone_update is not None:
logger.debug(
f"Zone {latest_zone.name} was updated in view {latest_zone.view.name}"
)
# Setting previous last zone update for next iteration:
_PREVIOUS_LAST_ZONE_UPDATE = last_zone_update
_increment_serial()
# Zone origin
origin = dns.name.from_text(name, dns.name.root)
# Create a new empty zone
zone = dns.zone.Zone(origin)
zone.rdclass = dns.rdataclass.IN
# get zones from netbox
nb_zones = Zone.objects.filter(
view__name=view_name, status=ZoneStatusChoices.STATUS_ACTIVE
).select_related("catz_identifier")
ptr_base = dns.name.from_text("zones", origin)
for nb_zone in nb_zones:
ttl = 0
qname = dns.name.from_text(nb_zone.name, dns.name.root)
# Create PTR record
#p_name = f"zid-{nb_zone.id:09d}"
p_name = nb_zone.catz_identifier.name
ptr_name = dns.name.from_text(p_name, ptr_base)
if not ptr_name.is_subdomain(origin):
raise ValueError(
"Catalog zone member identifier {ptr_name.to_text()} not a subdomain"
)
rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.PTR, qname.to_text()
)
rdataset = zone.find_rdataset(ptr_name, dns.rdatatype.PTR, create=True)
rdataset.add(rdata, ttl)
# Configure DNSSec Policy for member Zone if DNSSec is enabled
if nb_zone.dnssec_policy:
# Configure policy
rid = dns.name.from_text("group", ptr_name)
policy_name = nb_zone.dnssec_policy.name.rstrip(" ")
group_name = f"dnssec-policy-{policy_name}"
rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.TXT, group_name
)
rdataset = zone.find_rdataset(rid, dns.rdatatype.TXT, create=True)
rdataset.add(rdata, ttl)
## Configure dnssec status for member zone
# status = str(1 if nb_zone.dnssec_policy else 0)
# rid = dns.name.from_text("enabled.dnssec.ext", ptr_name)
# rdata = dns.rdata.from_text(dns.rdataclass.IN, dns.rdatatype.TXT, status)
# rdataset = zone.find_rdataset(rid, dns.rdatatype.TXT, create=True)
# rdataset.add(rdata, ttl)
# SOA Record components
ttl = 0
rclass = dns.rdataclass.IN
rtype = dns.rdatatype.SOA
mname = dns.name.from_text("invalid", dns.name.root)
rname = dns.name.from_text("invalid", dns.name.root)
serial = _SERIAL_OBJ.value
refresh = 60
retry = 10
expire = 1209600
minimum = 0
# Create SOA rdata object
soa_rdata = dns.rdata.from_text(
rclass,
rtype,
f"{mname} {rname} {serial} {refresh} {retry} {expire} {minimum}",
)
# Create Rdataset and add the RDATA to it
soa_rdataset = dns.rdataset.Rdataset(rclass, rtype)
soa_rdataset.add(soa_rdata, ttl)
# Add to the origin node in the zone
node = zone.find_node(origin, create=True)
node.rdatasets.append(soa_rdataset)
# NS record for catz.
ns_name = dns.name.from_text("invalid", dns.name.root)
ns_rdata = dns.rdata.from_text(
dns.rdataclass.IN, dns.rdatatype.NS, str(ns_name)
)
ns_rdataset = dns.rdataset.Rdataset(dns.rdataclass.IN, dns.rdatatype.NS)
ns_rdataset.add(ns_rdata, 0)
# Add to node (catz. is the origin)
ns_node = zone.find_node(origin, create=True)
ns_node.rdatasets.append(ns_rdataset)
# TXT record for version.catz.
version_name = dns.name.from_text(
"version", origin
) # relative to origin "catz."
txt_rdata = dns.rdata.from_text(dns.rdataclass.IN, dns.rdatatype.TXT, '"2"')
txt_rdataset = dns.rdataset.Rdataset(dns.rdataclass.IN, dns.rdatatype.TXT)
txt_rdataset.add(txt_rdata, 0)
# Add to node version.catz.
txt_node = zone.find_node(version_name, create=True)
txt_node.rdatasets.append(txt_rdataset)
return zone
def _generate_member_identifier() -> None:
return b32encode(uuid4().bytes)[0:26].lower().decode('UTF-8')
def update_member_identifier(zone: Zone) -> None:
CatalogZoneMemberIdentifier.objects.update_or_create(
zone=zone,
defaults={"name": _generate_member_identifier},
)
@@ -0,0 +1,54 @@
import logging
import socketserver
import socket
logger = logging.getLogger("dns-transfer-endpoint")
class DNSAddressMixin:
def _resolve_address(self, server_address, socktype, proto):
host, port = server_address
infos = socket.getaddrinfo(
host,
port,
socket.AF_UNSPEC,
socktype,
proto,
socket.AI_PASSIVE
)
family, _, _, _, sockaddr = infos[0]
self.address_family = family
return sockaddr
class TCPDNSServer(DNSAddressMixin, socketserver.TCPServer):
allow_reuse_address = True
def __init__(self, server_address, handler_class, keyring, tsig_view_map):
sockaddr = self._resolve_address(
server_address,
socket.SOCK_STREAM,
socket.IPPROTO_TCP
)
super().__init__(sockaddr, handler_class)
self.keyring = keyring
self.tsig_view_map = tsig_view_map
class UDPDNSServer(DNSAddressMixin, socketserver.UDPServer):
allow_reuse_address = True
def __init__(self, server_address, handler_class, keyring, tsig_view_map):
sockaddr = self._resolve_address(
server_address,
socket.SOCK_DGRAM,
socket.IPPROTO_UDP
)
super().__init__(sockaddr, handler_class)
self.keyring = keyring
self.tsig_view_map = tsig_view_map
@@ -0,0 +1,413 @@
import logging
import socketserver
import socket
import dns.query
import dns.message
import dns.tsigkeyring
import dns.name
import dns.zone
import dns.rdatatype
import dns.rdataclass
import dns.rdtypes
import dns.exception
import dns.renderer
from netbox_dns.models import Zone, Record
from netbox_dns.choices import ZoneStatusChoices, RecordStatusChoices
from . import catalog_zone_manager as catzm
logger = logging.getLogger("dns-transfer-endpoint")
class DNSBaseRequestHandler(socketserver.BaseRequestHandler):
def __init__(self, request, client_address, server) -> None:
self.MAX_WIRE = 65535
self.RESERVED_TSIG = 300
super().__init__(request, client_address, server)
# _getZoneFromNB rewritten
def _getZoneFromNB(self, zone_name, view_name) -> dns.zone.Zone:
# Find the zone
try:
nb_zone = Zone.objects.get(
name=zone_name,
view__name=view_name,
status=ZoneStatusChoices.STATUS_ACTIVE,
)
except Zone.DoesNotExist:
return None
# Build DNS zone
zone = dns.zone.Zone(zone_name, dns.name.root)
zone.rdclass = dns.rdataclass.IN
nb_records = Record.objects.filter(
zone=nb_zone, status=RecordStatusChoices.STATUS_ACTIVE
)
rdatasets_dict = {}
for record in nb_records:
rdtype = dns.rdatatype.from_text(record.type)
if not record.name:
name = zone.origin
elif record.name.endswith("."):
name = dns.name.from_text(record.name)
else:
name = dns.name.from_text(record.name, origin=zone.origin)
# If the record has no TTL, use the zone default
ttl = record.ttl or nb_zone.default_ttl
# Apply quoting for TXT records to stop tokanizer
# from cutting it up:
value = record.value
if rdtype == dns.rdatatype.TXT:
if value.startswith('"') and value.endswith('"'):
value = value[1:-1].replace('" "', "").replace('"', '"')
if len(value) > 255:
# This is a bug fix for netbox. If netbox allowed for
# an unquoted value to be larger then 255 characters,
# it misunderstood everything behind a ; as a comment.
chunks = [
'"{}"'.format(value[i : i + 255])
for i in range(0, len(value), 255)
]
value = " ".join(chunks)
else:
value = f'"{value}"'
rdata = dns.rdata.from_text(
dns.rdataclass.IN,
rdtype,
value,
relativize=False,
origin=zone.origin,
)
# Initialize rdataset if it doesn't exist for this name and type
if name not in rdatasets_dict:
rdatasets_dict[name] = {}
if rdtype not in rdatasets_dict[name]:
rdatasets_dict[name][rdtype] = dns.rdataset.Rdataset(
dns.rdataclass.IN, rdtype
)
# Add the rdata to the appropriate rdataset
rdatasets_dict[name][rdtype].add(rdata, ttl)
# Now, add all rdatasets to the zone
for name, rdtypes in rdatasets_dict.items():
for rdtype, rdataset in rdtypes.items():
# Ensure rdataset has the same rdclass as the zone
if rdataset.rdclass != zone.rdclass:
raise ValueError(
f"rdataset rdclass {rdataset.rdclass} does not match zone rdclass {zone.rdclass}"
)
# Check if the rdataset has any rdata before creating an RRset
if not rdataset:
logger.debug(f"Skipping empty rdataset for {name} {rdtype}")
continue # Skip empty rdataset
# Replace the rdataset for the given name and type
zone.replace_rdataset(name, rdataset)
return zone
def _denyRequestBadTSIG(self, wire, tsig_error: dns.rcode) -> None:
# Use empty keyring to parse TSIG without validating
query = dns.message.from_wire(
wire, keyring={}, ignore_trailing=True, continue_on_error=True
)
# Make a response
response = dns.message.make_response(query)
response.set_rcode(dns.rcode.REFUSED)
if query.had_tsig:
# Add TSIG with BADKEY, but do not sign (no MAC)
response.use_tsig(
keyring={}, # empty; we're not signing
keyname=query.keyname,
tsig_error=tsig_error,
)
self.denyRequest(query)
def _send_response(self, data) -> None:
raise NotImplementedError
def _deny_request(self, query, rcode: dns.rcode = dns.rcode.REFUSED) -> None:
response = dns.message.make_response(query)
response.set_rcode(rcode)
wire = response.to_wire(multi=False)
self._send_response(wire)
def _handle_soa_request(self, query, soa_rrset, zone, peer, nb_view, dname) -> None:
# We assume that the SOA rdataset has at least one record (it usually does).
soa_rdata = soa_rrset[0] # Get the first SOA record
# Now, create the rrset from the soa_rdata
rrset = dns.rrset.from_rdata(zone.origin, soa_rrset.ttl, soa_rdata)
response = dns.message.make_response(query)
# Set the Authoritative Answer flag
response.flags |= dns.flags.AA
# Append the rrset to the response's answer section
response.answer.append(rrset)
# TSIG response
if query.had_tsig:
# If key was found in DB
if query.keyname in self.server.keyring:
response.use_tsig(
self.server.keyring, keyname=query.keyname, original_id=query.id
)
else:
# If key is unknown
response.set_rcode(dns.rcode.REFUSED)
# Generate new key for keyname provided
# keyname = query.keyname
# b64 = base64.b64encode(urandom(32)).decode("ascii")
# newkey = dns.tsigkeyring.from_text({ keyname: b64 })
response.use_tsig(
self.server.keyring,
keyname=query.keyname,
tsig_error=dns.rcode.BADKEY,
)
data = response.to_wire(max_size=512)
self._send_response(data)
logger.debug(f"{peer} SOA {nb_view.name}/{dname}")
def _handle_axfr_request(self, query, zone, peer, nb_view, dname) -> None:
rrsets = []
soa_rrset = None
for name, rdataset in zone.iterate_rdatasets():
if not name.is_absolute():
name = name.concatenate(zone.origin)
rrset = dns.rrset.from_rdata_list(name, rdataset.ttl, rdataset)
if rdataset.rdtype == dns.rdatatype.SOA and soa_rrset is None:
soa_rrset = rrset
else:
rrsets.append(rrset)
rrsets.insert(0, soa_rrset) # Opening SOA
rrsets.append(soa_rrset) # Closing SOA
# 2. Create a Renderer for the first message
r = dns.renderer.Renderer(
id=query.id,
flags=(dns.flags.QR | dns.flags.AA),
max_size=self.MAX_WIRE,
origin=None,
)
r.add_question(
query.question[0].name,
query.question[0].rdtype,
query.question[0].rdclass,
)
# 3. Loop through RRsets
tsig_ctx = None
for rrset in rrsets:
# logger.debug(f"Iterating over rrset {rrset}. tsig_ctx: {tsig_ctx}")
try:
# logger.debug(f"Adding {rrset} to renderer object")
r.add_rrset(dns.renderer.ANSWER, rrset)
if r.max_size - len(r.output.getvalue()) < self.RESERVED_TSIG:
raise dns.exception.TooBig("TSIG wont fit")
except dns.exception.TooBig:
# TSIG chain previous message
r.write_header()
tsig_ctx = r.add_multi_tsig(
ctx=tsig_ctx,
secret=self.server.keyring[query.keyname],
keyname=query.keyname,
fudge=300,
id=query.id,
tsig_error=0,
other_data=b"",
request_mac=r.mac if tsig_ctx else query.mac,
)
wire = r.get_wire()
self.request.sendall(len(wire).to_bytes(2, "big") + wire)
# Start new renderer
r = dns.renderer.Renderer(
id=query.id,
flags=(dns.flags.QR | dns.flags.AA),
max_size=self.MAX_WIRE,
origin=None,
)
r.add_question(
query.question[0].name,
query.question[0].rdtype,
query.question[0].rdclass,
)
r.add_rrset(dns.renderer.ANSWER, rrset)
# 4. Final message with terminating TSIG
r.write_header()
# logger.debug(f"Final message. tsig_ctx: {tsig_ctx}")
tsig_ctx = r.add_multi_tsig(
ctx=tsig_ctx,
secret=self.server.keyring[query.keyname],
keyname=query.keyname,
fudge=300,
id=query.id,
tsig_error=0,
other_data=b"",
# request_mac=r.mac if tsig_ctx else None,
request_mac=r.mac if tsig_ctx else query.mac,
)
wire = r.get_wire()
self._send_response(wire)
logger.debug(f"{peer} AXFR {nb_view.name}/{dname}")
def _handle_dns_query(self, wire) -> None:
peer = self.client_address[0]
try:
query = dns.message.from_wire(
wire,
keyring=self.server.keyring,
continue_on_error=False,
ignore_trailing=True
)
except dns.tsig.BadSignature as e:
logger.warning(
f"Request denied from {peer} failed TSIG verification: {e}"
)
self._denyRequestBadTSIG(wire, dns.rcode.BADSIG)
return
except (dns.message.UnknownTSIGKey, dns.tsig.BadAlgorithm) as e:
logger.warning(f"Request denied from {peer} with bad TSIG key: {e}")
self._denyRequestBadTSIG(wire, dns.rcode.BADKEY)
return
except Exception as e:
logger.error("Error parsing query: ", e)
return
# If there was no question in the query, refuse
if len(query.question) != 1:
self._deny_request(query)
return
question = query.question[0]
qname = question.name
qtype = question.rdtype
dname = qname.to_text().rstrip(".")
# Only process AXFR/SOA queris
if qtype not in (dns.rdatatype.AXFR, dns.rdatatype.SOA):
logger.warning(
f"Request denied from {peer}: Request was not AXFR or SOA (Type: {qtype})"
)
self._deny_request(query)
return
# Identify TSIG key used
if not query.had_tsig:
logger.warning(f"Request denied from {peer}: No TSIG key used")
self._deny_request(query)
return
key_name = query.keyname.canonicalize().to_text()
# Check if the key matches a view
nb_view = self.server.tsig_view_map.get(key_name)
if not nb_view:
logger.warning(
f"Request denied from {peer}: {key_name} does not match a view"
)
self._deny_request(query)
return
# Check if catalog zone
if dname == "catz" or dname == f"{nb_view.name}.catz":
zone = catzm.create_zone(dname, nb_view.name)
else:
zone = self._getZoneFromNB(dname, nb_view.name)
# When zone was not found, let client know
if not zone:
logger.warning(f"Zone {dname} not found in view {nb_view.name}")
self._deny_request(query)
return
# Retrieve the existing SOA record from the Zone
soa_rrset = zone.get_rdataset(zone.origin, dns.rdatatype.SOA)
if soa_rrset is None:
logger.error(f"Zone {dname} has no SOA — aborting")
return
if qtype == dns.rdatatype.SOA:
self._handle_soa_request(query, soa_rrset, zone, peer, nb_view, dname)
elif qtype == dns.rdatatype.AXFR:
self._handle_axfr_request(query, zone, peer, nb_view, dname)
class UDPRequestHandler(DNSBaseRequestHandler):
def __init__(self, request, client_address, server) -> None:
super().__init__(request, client_address, server)
def _send_response(self, data) -> None:
sock = self.request[1]
sock.sendto(data, self.client_address)
def handle(self) -> None:
data, sock = self.request
peer = self.client_address[0]
try:
self._handle_dns_query(data)
except Exception as e:
logger.error(f"Error handling request from {peer}: {e}")
import traceback
traceback.print_exc()
class TCPRequestHandler(DNSBaseRequestHandler):
def __init__(self, request, client_address, server) -> None:
super().__init__(request, client_address, server)
def _send_response(self, data) -> None:
length = len(data).to_bytes(2, byteorder="big")
self.request.sendall(length + data)
def handle(self) -> None:
peer = self.client_address[0]
sock = self.request # TCP socket
sock.settimeout(10.0) # Default 10 second timeout for inactivity
try:
while True:
# Read 2-byte length prefix
length_data = sock.recv(2)
if not length_data:
return # connection closed by peer
if len(length_data) < 2:
# Incomplete length data, wait for more or fail
while len(length_data) < 2:
chunk = sock.recv(2 - len(length_data))
if not chunk:
return
length_data += chunk
length = int.from_bytes(length_data, byteorder="big")
wire = b""
while len(wire) < length:
chunk = sock.recv(length - len(wire))
if not chunk:
return # connection closed
wire += chunk
self._handle_dns_query(wire)
except socket.timeout:
logger.debug(f"Connection from {peer} timed out")
except Exception as e:
logger.error(f"Error handling request from {peer}: {e}")
import traceback
traceback.print_exc()
@@ -0,0 +1,40 @@
from django.db.models.signals import pre_save, post_save
from django.dispatch import receiver
from netbox_dns.models import Zone
from .service.endpoint import catalog_zone_manager as catzm
@receiver(pre_save, sender=Zone)
def zone_pre_save(sender, instance, **kwargs):
"""
Cache the old name so post_save can see if it changed.
"""
if instance.pk:
try:
instance._old_name = (
sender.objects
.only("name")
.get(pk=instance.pk)
.name
)
except sender.DoesNotExist:
instance._old_name = None
else:
instance._old_name = None
@receiver(post_save, sender=Zone)
def sync_catalog_zone_identifier(sender, instance, created, **kwargs):
"""
Ensure CatalogZoneMemberIdentifier exists for each Zone
and keep its identifier in sync.
"""
if created:
# Create the related object on Zone creation
catzm.update_member_identifier(instance)
else:
old_name = getattr(instance, "_old_name", None)
# If the name did not change, do nothing
if old_name == instance.name:
return
catzm.update_member_identifier(instance)