Version 2.0

.github/workflows/build-push.yml

@@ -3,7 +3,7 @@ name: Create and publish a Docker image
 # Configures this workflow to run every time a change is pushed to the branch called `release`.
 on:
   push:
-    branches: ['dev']
+    branches: ['main']
 
 # Defines two custom environment variables for the workflow. These are used for the Container registry domain, and a name for the Docker image that this workflow builds.
 env:
@@ -38,6 +38,8 @@ jobs:
         uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
         with:
           images: ${{ env.REGISTRY }}/${{ github.actor }}/${{ env.IMAGE_NAME }}
+          flavor: |
+            latest=true
       # This step uses the `docker/build-push-action` action to build the image, based on your repository's `Dockerfile`. If the build succeeds, it pushes the image to GitHub Packages.
       # It uses the `context` parameter to define the build's context as the set of files located in the specified path. For more information, see "[Usage](https://github.com/docker/build-push-action#usage)" in the README of the `docker/build-push-action` repository.
       # It uses the `tags` and `labels` parameters to tag and label the image with the output from the "meta" step.
@@ -48,6 +50,7 @@ jobs:
           context: .
           push: true
           tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
 
       # This step generates an artifact attestation for the image, which is an unforgeable statement about where and how it was built. It increases supply chain security for people who consume the image. For more information, see "[AUTOTITLE](/actions/security-guides/using-artifact-attestations-to-establish-provenance-for-builds)."
       - name: Generate artifact attestation

.github/workflows/demopush.yml

@@ -1,54 +0,0 @@
-#
-name: Demo Push
-
-# This workflow runs when any of the following occur:
-# - A push is made to a branch called `main` or `seed`
-# - A tag starting with "v" is created
-# - A pull request is created or updated
-on:
-  push:
-    branches:
-      - disabled
-#    tags:
-#      - v*
-#  pull_request:
-  # This creates an environment variable called `IMAGE_NAME ` with the value `ghtoken_product_demo`.
-env:
-  REGISTRY: ghcr.io
-  IMAGE_NAME: slaacsense
-#
-jobs:
-  # This pushes the image to GitHub Packages.
-  push:
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      packages: write
-      attestations: write
-      pages: write
-      id-token: write
-      #
-    steps:
-      - uses: actions/checkout@v4
-
-      - name: Build image
-        run: docker build . --file Dockerfile --tag $IMAGE_NAME --label "runnumber=${GITHUB_RUN_ID}"
-
-      - name: Log in to registry
-        run: echo "${{ secrets.GITHUB_TOKEN }}" | docker login ghcr.io -u ${{ github.actor }} --password-stdin
-
-      - name: Push image
-        run: |
-          IMAGE_ID=ghcr.io/${{ github.repository_owner }}/$IMAGE_NAME
-          # This changes all uppercase characters to lowercase.
-          IMAGE_ID=$(echo $IMAGE_ID | tr '[A-Z]' '[a-z]')
-          # This strips the git ref prefix from the version.
-          VERSION=$(echo "${{ github.ref }}" | sed -e 's,.*/\(.*\),\1,')
-          # This strips the "v" prefix from the tag name.
-          [[ "${{ github.ref }}" == "refs/tags/"* ]] && VERSION=$(echo $VERSION | sed -e 's/^v//')
-          # This uses the Docker `latest` tag convention.
-          [ "$VERSION" == "main" ] && VERSION=latest
-          echo IMAGE_ID=$IMAGE_ID
-          echo VERSION=$VERSION
-          docker tag $IMAGE_NAME $IMAGE_ID:$VERSION
-          docker push $IMAGE_ID:$VERSION

README.md

@@ -12,20 +12,22 @@ Define the environment variables in the docker-compose file, then run: `docker c
 
 ### Environment variables:
 
-| Variable Name         | Description                                                                              | Example Value                                                         |
-|-----------------------|------------------------------------------------------------------------------------------|-----------------------------------------------------------------------|
-| `OPNSENSE_URL`        | The base URL of your OPNsense instance                                                   | http://192.168.1.1 (required)                                         
-| `OPNSENSE_API_KEY`    | OPNsense API key                                                                         | `your_opnsense_api_key` (required)                                    |
-| `OPNSENSE_API_SECRET` | OPNsense API secret                                                                      | `a_very_secret_token` (required)                                      |
-| `TECHNITIUM_URL`      | The base URL of your Technitium DNS instance                                             | `dns.myawesomehome.home.arpa` (required)                              |
-| `TECHNITIUM_TOKEN`    | Technitium DNS token                                                                     | `another_very_secret_token` (required)                                |
+| Variable Name         | Description                                                                              | Example Value                                                          |
+|-----------------------|------------------------------------------------------------------------------------------|------------------------------------------------------------------------|
+| `OPNSENSE_URL`        | The base URL of your OPNsense instance                                                   | http://192.168.1.1 (required)                                          
+| `OPNSENSE_API_KEY`    | OPNsense API key                                                                         | `your_opnsense_api_key` (required)                                     |
+| `OPNSENSE_API_SECRET` | OPNsense API secret                                                                      | `a_very_secret_token` (required)                                       |
+| `TECHNITIUM_URL`      | The base URL of your Technitium DNS instance                                             | `dns.myawesomehome.home.arpa` (required)                               |
+| `TECHNITIUM_TOKEN`    | Technitium DNS token                                                                     | `another_very_secret_token` (required)                                 |
 | `DNS_ZONE_SUBNETS`    | Comma separated DNS zones and IPv4 subnet                                                | `192.168.1.0/24=lan.home.arpa,192.168.2.0/24=dmz.home.arpa` (required) |
-| `DO_V4`               | If set to true, A records will be configured, otherwise only AAAA records are configured | `false` (defaults to false)                                           |
-| `VERIFY_HTTPS`        | Verify OPNsense and Technitium's SSL certificates                                        | `true` (defaults to true)                                             |
-| `CLOCK`               | Interval between updates (in seconds)                                                    | `30` (defaults to 30)                                                 |
+| `DO_V4`               | If set to true, A records will be configured, otherwise only AAAA records are configured | `false` (defaults to false)                                            |
+| `IGNORE_LINK_LOCAL`   | If set to true, link local IPv6 addresses wil be ignored                                 | `true` (defaults to true)                                              |
+| `VERIFY_HTTPS`        | Verify OPNsense and Technitium's SSL certificates                                        | `true` (defaults to true)                                              |
+| `CLOCK`               | Interval between updates (in seconds)                                                    | `30` (defaults to 30)                                                  |
 
 ### Note
 You have to create the corresponding DNS zones in the Technitium dashboard, you can configure them as primary or conditional forwarder zones.
+If DNS records are not being added, make sure that the corresponding reverse zone exists in Technitium DNS, otherwise the script will fail silently.
 
 ### Contributing:
 I welcome contributions! Feel free to submit issues, feature requests, or pull requests.

docker-compose.yml

@@ -1,9 +1,11 @@
 version: '3.6'
 services:
   slaacsense:
+    image: ghcr.io/notherealmarco/slaacsense:latest
     build: .
     container_name: slaacsense
     restart: unless-stopped
+    pull_policy: always
     environment:
       - OPNSENSE_URL=${OPNSENSE_URL}
       - OPNSENSE_API_KEY=${OPNSENSE_API_KEY}

main.py

@@ -4,142 +4,122 @@ import time
 import requests
 import ipaddress
 import urllib3
+from collections import defaultdict
 
 # Environment variables
-# URL of the OPNsense instance
 OPNSENSE_URL = os.getenv("OPNSENSE_URL", None)
-# API key for the OPNsense instance
 OPNSENSE_API_KEY = os.getenv("OPNSENSE_API_KEY", None)
-# API secret for the OPNsense instance
 OPNSENSE_API_SECRET = os.getenv("OPNSENSE_API_SECRET", None)
-# URL of the Technitium DNS server
 TECHNITIUM_URL = os.getenv("TECHNITIUM_URL", None)
-# Token for the Technitium DNS server
 TECHNITIUM_TOKEN = os.getenv("TECHNITIUM_TOKEN", None)
-# Subnets for the DNS zones
 DNS_ZONE_SUBNETS = os.getenv("DNS_ZONE_SUBNETS", None)
-# Flag to indicate whether to do IPv4 or not
 DO_V4 = (os.getenv("DO_V4", "false").lower() == "true")
-# Flag to indicate whether to verify HTTPS or not
+IGNORE_LINK_LOCAL = (os.getenv("IGNORE_LINK_LOCAL", "true").lower() == "true")
 VERIFY_HTTPS = (os.getenv("VERIFY_HTTPS", "true").lower() == "true")
-# Clock interval for the main loop
 CLOCK = int(os.getenv("CLOCK", "30"))
 
-
 def get_opnsense_data(path):
-    """
-    Function to get data from the OPNsense API.
-
-    Args:
-        path (str): The API endpoint to hit.
-
-    Returns:
-        dict: The JSON response from the API call.
-    """
     r = requests.get(url=OPNSENSE_URL + path, verify=VERIFY_HTTPS, auth=(OPNSENSE_API_KEY, OPNSENSE_API_SECRET))
     if r.status_code != 200:
         logging.error("Error occurred" + str(r.status_code) + ": " + r.text)
         return None
     return r.json()
 
-
 def get_ndp():
-    """
-    Function to get the NDP table from the OPNsense API.
-
-    Returns:
-        dict: The JSON response from the API call.
-    """
     return get_opnsense_data("/api/diagnostics/interface/search_ndp")
 
-
 def get_dhcp4_leases():
-    """
-    Function to get the DHCPv4 leases from the OPNsense API.
-
-    Returns:
-        dict: The JSON response from the API call.
-    """
     return get_opnsense_data("/api/dhcpv4/leases/searchLease")
 
-
 def build_matches(ndp, leases):
-    """
-    Function to build matches between NDP and DHCPv4 leases.
-
-    Args:
-        ndp (dict): The NDP table.
-        leases (dict): The DHCPv4 leases.
-
-    Returns:
-        set: A set of matches.
-    """
     matches = set()
+    hostname_to_macs = defaultdict(lambda: defaultdict(list))
+
     for e in leases["rows"]:
-        ip6s = tuple(x["ip"].split("%")[0] for x in ndp["rows"] if x["mac"] == e["mac"])
+        ip6s = tuple(
+            x["ip"].split("%")[0] for x in ndp["rows"]
+            if x["mac"] == e["mac"] and x["intf_description"] == e["if_descr"]
+        )
+        if IGNORE_LINK_LOCAL:
+            ip6s = tuple(ip for ip in ip6s if not ipaddress.ip_address(ip).is_link_local)
         if len(ip6s) == 0 and not DO_V4:
             continue
-        matches.add((e["address"], ip6s, e["hostname"]))
-    return matches
 
+        hostname = e["hostname"]
+        if hostname:
+            hostname_to_macs[hostname][e["if_descr"]].append(e["mac"])
+
+        matches.add((e["address"], ip6s, hostname, e["if_descr"], e["mac"]))
+
+    # Handle duplicate hostnames on the same interface
+    adjusted_matches = set()
+    for match in matches:
+        ip4, ip6s, hostname, if_descr, mac = match
+        if hostname and len(hostname_to_macs[hostname][if_descr]) > 1:
+            # Add the last 4 characters of the MAC address to the hostname
+            hostname = f"{hostname}-{mac.replace(':', '')[-4:]}"
+        adjusted_matches.add((ip4, ip6s, hostname))
+
+    return adjusted_matches
 
 def find_zone(zones, ip4):
-    """
-    Function to find the DNS zone for a given IPv4 address.
-
-    Args:
-        zones (list): The list of DNS zones.
-        ip4 (str): The IPv4 address.
-
-    Returns:
-        str: The DNS zone for the given IPv4 address.
-    """
     for zone in zones:
         if ip4 in zone[0]: return zone[1]
     return None
 
+def get_existing_records(domain, zone):
+    url = f"{TECHNITIUM_URL}/api/zones/records/get?token={TECHNITIUM_TOKEN}&domain={domain}.{zone}"
+    r = requests.get(url=url, verify=VERIFY_HTTPS)
+    if r.status_code != 200:
+        logging.error("Error fetching existing records: " + str(r.status_code) + ": " + r.text)
+        return []
+    return r.json().get("response", {}).get("records", [])
 
-def make_record(zones, match):
-    """
-    Function to make a DNS record for a given match.
+def delete_record(zone, domain, record_type, value):
+    url = f"{TECHNITIUM_URL}/api/zones/records/delete?token={TECHNITIUM_TOKEN}&domain={domain}.{zone}&zone={zone}&type={record_type}&value={value}"
+    r = requests.get(url=url, verify=VERIFY_HTTPS)
+    if r.status_code != 200:
+        logging.error("Error deleting record: " + str(r.status_code) + ": " + r.text)
+    else:
+        logging.info(f"Deleted {record_type} record for {value} in {domain}.{zone}")
 
-    Args:
-        zones (list): The list of DNS zones.
-        match (tuple): The match to make a record for.
-    """
+def add_record(zone, domain, record_type, ip):
+    url = f"{TECHNITIUM_URL}/api/zones/records/add?token={TECHNITIUM_TOKEN}&domain={domain}.{zone}&type={record_type}&ttl=5&expiryTtl=604800&overwrite=false&ptr=true&ipAddress={ip}"
+    r = requests.get(url=url, verify=VERIFY_HTTPS)
+    if r.status_code != 200:
+        logging.error("Error adding record: " + str(r.status_code) + ": " + r.text)
+    else:
+        logging.info(f"Added {record_type} record for {ip} in {domain}.{zone}")
+
+def sync_records(zones, match):
     zone = find_zone(zones, ipaddress.ip_address(match[0]))
     if zone is None:
         logging.warning("Could not find a DNS zone for " + match[0])
         return
 
     ip4 = match[0]
-    ip6s = [ipaddress.ip_address(x) for x in match[1]]
+    ip6s = [ipaddress.ip_address(x).compressed for x in match[1]]
     hostname = match[2]
 
     if hostname == "":
-        logging.warning("no hostname found for " + match[0])
+        logging.warning("No hostname found for " + match[0])
         return
 
-    for ip6 in ip6s:
-        v6path = "/api/zones/records/add?token=" + TECHNITIUM_TOKEN + "&domain=" + hostname + "." + zone + "&type=AAAA&ttl=1&overwrite=true&ptr=true&ipAddress=" + ip6.exploded
-        logging.info("Inserting AAAA: " + hostname + "." + zone + " " + ip6.compressed)
-        r = requests.get(url=TECHNITIUM_URL + v6path, verify=VERIFY_HTTPS)
-        if r.status_code != 200:
-            logging.error("Error occurred" + str(r.status_code) + ": " + r.text)
-            continue
+    existing_records = get_existing_records(hostname, zone)
+    existing_ips = {ipaddress.ip_address(r["rData"]["ipAddress"]).compressed for r in existing_records if r["type"] in ["A", "AAAA"]}
+    current_ips = set([ipaddress.ip_address(ip4).compressed] if DO_V4 else []) | set(ip6s)
 
-    if DO_V4:
-        v4path = "/api/zones/records/add?token=" + TECHNITIUM_TOKEN + "&domain=" + hostname + "." + zone + "&type=A&ttl=1&overwrite=true&ptr=true&ipAddress=" + ip4
-        logging.info("Inserting A: " + hostname + "." + zone + " " + ip4)
-        r = requests.get(url=TECHNITIUM_URL + v4path, verify=VERIFY_HTTPS)
-        if r.status_code != 200:
-            logging.error("Error occurred" + str(r.status_code) + ": " + r.text)
+    # Delete outdated records
+    for ip in existing_ips - current_ips:
+        record_type = "A" if "." in ip else "AAAA"
+        delete_record(zone, hostname, record_type, ip)
 
+    # Add missing records
+    for ip in current_ips - existing_ips:
+        record_type = "A" if "." in ip else "AAAA"
+        add_record(zone, hostname, record_type, ip)
 
 def run():
-    """
-    Main function to run the script.
-    """
     if not VERIFY_HTTPS:
         urllib3.disable_warnings()
 
@@ -163,17 +143,10 @@ def run():
         previous_matches = matches
 
         for match in new_matches:
-            make_record(zones, match)
+            sync_records(zones, match)
         time.sleep(CLOCK)
 
-
 def verify_env() -> bool:
-    """
-    Function to verify the environment variables.
-
-    Returns:
-        bool: True if all mandatory environment variables are set, False otherwise.
-    """
     if not OPNSENSE_URL: return False
     if not OPNSENSE_API_KEY: return False
     if not OPNSENSE_API_SECRET: return False
@@ -182,7 +155,6 @@ def verify_env() -> bool:
     if not DNS_ZONE_SUBNETS: return False
     return True
 
-
 if __name__ == "__main__":
     logging.getLogger().setLevel(os.getenv("LOG_LEVEL", "INFO"))
     logging.info("loading environment...")
@@ -195,4 +167,4 @@ if __name__ == "__main__":
     logging.info("OPNSENSE_URL: {}".format(OPNSENSE_URL))
     logging.info("TECHNITIUM_URL: {}".format(TECHNITIUM_URL))
     logging.info("VERIFY_HTTPS: {}".format(VERIFY_HTTPS))
-    run()
+    run()