Initial bind-operator: 9 CRDs + controllers

Implements a Kubernetes operator that manages fleets of BIND9 servers
declaratively, using controller-runtime (matching forgebot conventions).

- add BindCluster reconciler: StatefulSet (pod-0 primary, secondaries),
  headless + client Services, rendered named.conf ConfigMap, TSIG keys
  Secret and rndc control Secret; watches dependent CRs to re-render
- add BindTSIGKey reconciler that generates key material into a Secret
- add BindZone/DNSRecord reconcilers using fully-dynamic delivery
  (rndc addzone + TSIG nsupdate against the primary pod)
- add BindCatalogZone reconciler so secondaries auto-provision zones
- add BindPolicy (RPZ), BindDNSSECPolicy, BindView, BindACL reconcilers
- render primary/secondary named.conf variants selected by pod ordinal
- generate CRDs, deepcopy and RBAC; add samples mapping the three Puppet
  roles (authoritative/resolver/external-dns) to three BindClusters
- add Makefile, Dockerfile.operator, Woodpecker CI and kind manifests
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# bind-operator
Kubernetes operator for managing BIND9 DNS clusters, zones, views, and TSIG keys
A Kubernetes operator that manages fleets of BIND9 servers declaratively:
StatefulSet-backed clusters with primary/secondary replication, and zones,
views, TSIG keys, ACLs, catalog zones, RPZ policies and DNSSEC policies as
custom resources.
## Architecture
Each `BindCluster` is a StatefulSet plus a headless Service (stable per-pod DNS)
and a client Service. **Ordinal-0 is the primary**; the remaining pods are
secondaries that replicate via AXFR/IXFR + NOTIFY. A per-pod PVC holds zone
databases and journals.
Zone content is delivered **dynamically**: the operator execs `rndc addzone` and
TSIG `nsupdate` against the primary pod (the same write path external-dns uses).
Cluster-wide config — `options`, `controls`, ACLs, views, `dnssec-policy` blocks
and `response-policy` clauses — is rendered into a ConfigMap-backed `named.conf`
and reloaded with `rndc reconfig`. New zones land on the secondaries
automatically through a **catalog zone**, so secondaries never need
per-zone reconfiguration.
```
BindCluster ──> StatefulSet (pod-0 = primary, pod-N = secondaries)
├─ headless Service (pod-0.<cluster>-headless.<ns>.svc…)
├─ client Service (ClusterIP / LoadBalancer)
├─ ConfigMap (named.conf.primary / .secondary + entrypoint)
├─ Secret <cluster>-keys (TSIG key clauses, included by named.conf)
└─ Secret <cluster>-rndc (rndc control key)
BindZone / DNSRecord ──rndc addzone + nsupdate──> primary ──catalog + AXFR──> secondaries
```
The named.conf is rendered in two variants (primary/secondary); an entrypoint
script picks one based on the pod ordinal.
## Custom Resources
| Kind | Purpose |
|------|---------|
| `BindCluster` | A set of BIND9 servers. `spec.mode`: `authoritative`, `resolver`, or `dynamic`. |
| `BindZone` | A forward/reverse zone (`primary`/`secondary`/`forward`/`stub`), records inline, optional dynamic-update + DNSSEC + catalog membership. |
| `DNSRecord` | A single record set applied via TSIG `nsupdate` — external-dns as a CRD. |
| `BindView` | A split-horizon view (`match-clients`, ordering, per-view recursion). |
| `BindTSIGKey` | A TSIG key; the operator generates material into a Secret (never stored in the CR). |
| `BindACL` | A reusable named `address_match_list`. |
| `BindCatalogZone` | A BIND catalog zone so secondaries auto-provision member zones. |
| `BindPolicy` | A Response Policy Zone (RPZ) / DNS firewall. |
| `BindDNSSECPolicy` | A `dnssec-policy` for automated signing. |
See `config/samples/` for worked examples.
## Migration mapping
The three Puppet-managed BIND roles map onto three `BindCluster`s:
| Puppet role | `BindCluster` | Mode |
|-------------|---------------|------|
| 3× authoritative masters | `auth` | `authoritative` (pod-0 primary, 2 secondaries) |
| 3× only-resolvers | `resolver` | `resolver` (3 identical recursive servers) |
| 3× external-dns | `externaldns` | `dynamic` (RFC2136 TSIG updates on primary) |
## Development
```sh
make generate # regenerate deepcopy, CRDs and RBAC from kubebuilder markers
make build # build the operator binary
make test # go test -race
make lint fmt # go vet / gofmt
```
### Local (kind)
```sh
kind create cluster --name bind
docker build -t bind-operator:dev -f Dockerfile.operator .
kind load docker-image bind-operator:dev --name bind
kubectl apply -f config/crd/bases/
kubectl apply -f hack/kind/manifests/
kubectl apply -f config/samples/
```
## CI
Woodpecker runs `pre-commit` (gofmt + vet), `test`, and a dry-run image `build`
on pull requests; pushing a `v*` tag builds and pushes
`git.unkin.net/unkin/bind-operator` to the Gitea registry.
## Notes & caveats
- The BIND container image (`spec.image`, default
`git.unkin.net/unkin/bind9:latest`) must ship `named`, `rndc` and `nsupdate`,
read `/run/named/named.conf`, and honour the operator's `/etc/bind` layout.
- Dynamic updates authenticate with `nsupdate -y`; the TSIG secret is passed on
the argv of an exec'd process inside the pod.
- RPZ IP-trigger encodings (`ip`, `client-ip`, `nsip`) are emitted verbatim;
QNAME and NSDNAME triggers are fully supported.