Authoritative zones: accept puppet client dynamic updates (#244)

Enables per-host RFC2136 updates from puppet (puppet-prod #475 profiles::dns::updater) to the bind-authoritative zones, via the .9 write endpoint.

## Changes
- add **client-update** BindTSIGKey (clusterRef bind-authoritative; operator generates the material into Secret client-update-tsig)
- set `dynamicUpdate: true` + `updateKeyRef: client-update` on all **18** authoritative zones → the operator renders `allow-update { key "client-update"; }`

## Key bridge (manual, per the TSIG plan)
The operator generates the client-update key value; it must reach puppet eyaml (`profiles::dns::updater::key_secret`) for clients to authenticate — until the planned Vault-sync/secret-reflection operator features exist. Get it with:
`kubectl -n bind-internal get secret client-update-tsig -o jsonpath='{.data.secret}' | base64 -d`

## Validated
kustomize build + kubeconform.

Reviewed-on: #244
Co-authored-by: Ben Vincent <ben@unkin.net>
Co-committed-by: Ben Vincent <ben@unkin.net>

apps/base/bind-internal/authoritative/tsigkey.yaml

@@ -9,3 +9,16 @@ metadata:
 spec:
   clusterRef: bind-authoritative
   algorithm: hmac-sha256
+---
+# Client-update key: puppet clients (profiles::dns::updater) nsupdate their own
+# records to the authoritative zones with this key. Operator generates the
+# material into Secret client-update-tsig; the same value must reach puppet
+# eyaml (or the planned Vault-sync bridge) for clients to authenticate.
+apiVersion: bind.unkin.net/v1alpha1
+kind: BindTSIGKey
+metadata:
+  name: client-update
+  namespace: bind-internal
+spec:
+  clusterRef: bind-authoritative
+  algorithm: hmac-sha256

apps/base/bind-internal/authoritative/zones.yaml

@@ -15,6 +15,8 @@ spec:
   zoneName: unkin.net
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -26,6 +28,8 @@ spec:
   zoneName: main.unkin.net
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -37,6 +41,8 @@ spec:
   zoneName: 13.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -48,6 +54,8 @@ spec:
   zoneName: 14.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -59,6 +67,8 @@ spec:
   zoneName: 15.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -70,6 +80,8 @@ spec:
   zoneName: 16.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -81,6 +93,8 @@ spec:
   zoneName: 17.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -92,6 +106,8 @@ spec:
   zoneName: 19.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -103,6 +119,8 @@ spec:
   zoneName: 20.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -114,6 +132,8 @@ spec:
   zoneName: 21.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -125,6 +145,8 @@ spec:
   zoneName: 22.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -136,6 +158,8 @@ spec:
   zoneName: 23.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -147,6 +171,8 @@ spec:
   zoneName: 24.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -158,6 +184,8 @@ spec:
   zoneName: 25.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -169,6 +197,8 @@ spec:
   zoneName: 26.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -180,6 +210,8 @@ spec:
   zoneName: 27.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -191,6 +223,8 @@ spec:
   zoneName: 28.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update
 ---
 apiVersion: bind.unkin.net/v1alpha1
 kind: BindZone
@@ -202,3 +236,5 @@ spec:
   zoneName: 29.18.198.in-addr.arpa
   type: primary
   defaultTTL: 600
+  dynamicUpdate: true
+  updateKeyRef: client-update