cyberchef: honour ingress.enabled, add null-safe hardening

Three changes, all about values that do not do what they promise:

1. Ingress gate (#93): the Ingress template is wrapped in
   {{- if .Values.ingress.enabled }}. The key already existed in
   values.yaml with default true but was never read, so switching it off
   did nothing. Both required() calls for domain and clusterIssuer live
   inside the Ingress file, so gating also removes the contradiction that
   one had to supply a domain and issuer in order to turn off an Ingress
   one does not want.

2. Null-safety for hardening, probes and resources (#99): an override
   written without children is YAML null and erased the whole default
   sub-tree, rendering "securityContext: null" - an unhardened container
   that starts and reports healthy.

3. values.schema.json types (#68 + #99): the blocks covered by the
   null-safety accept null. This is load-bearing only for keys that have
   no chart default (e.g. resources.limits): there Helm has nothing to
   delete, so the null survives into schema validation and a strict
   "object" type rejected it outright.

Rendering with normal values is byte-identical to 7.0.0.

cyberchef/Chart.yaml

@@ -5,7 +5,7 @@ icon: https://raw.githubusercontent.com/gchq/CyberChef/master/src/web/static/ima
 
 type: application
 
-version: 7.1.0+up11.4.0
+version: 8.0.0+up11.4.0
 appVersion: "11.4.0"
 
 maintainers:

cyberchef/templates/NOTES.txt

@@ -1,6 +1,8 @@
 {{- $replicas := include "cyberchef.replicas" (dict "scaleDown" .Values.scaleDown "replicas" .Values.cyberchef.replicas) -}}
 CyberChef {{ .Chart.AppVersion }} — release {{ .Release.Name }} in namespace {{ .Release.Namespace }}.
 
+{{- if .Values.ingress.enabled }}
+
 ACCESS
   https://{{ .Values.ingress.domain }}
 
@@ -11,11 +13,25 @@ ACCESS
 
   This chart has no secrets and no volumes — the two ingress values above are
   everything an installation needs.
+{{- else }}
+
+ACCESS — NO INGRESS
+  ingress.enabled is false, so this release has no Ingress and no certificate;
+  ingress.domain and ingress.clusterIssuer are not needed. The app is only
+  reachable inside the cluster, as
+  {{ .Release.Name }}-{{ .Chart.Name }}-service:80. To open it locally:
+
+    kubectl -n {{ .Release.Namespace }} port-forward svc/{{ .Release.Name }}-{{ .Chart.Name }}-service 8080:80
+
+  Then browse to http://localhost:8080. Set ingress.enabled=true together with
+  ingress.domain and ingress.clusterIssuer to publish it instead.
+{{- end }}
 {{ if eq $replicas "0" }}
 SCALED TO ZERO
-  {{ if .Values.scaleDown }}scaleDown: true{{ else }}cyberchef.replicas: 0{{ end }} — the deployment runs with replicas: 0, so the URL
-  above answers 503 until you set it back and upgrade again. Service and
-  Ingress stay in place, so the certificate is not re-issued.
+  {{ if .Values.scaleDown }}scaleDown: true{{ else }}cyberchef.replicas: 0{{ end }} — the deployment runs with replicas: 0, so the endpoint
+  above does not answer until you set it back and upgrade again. Service{{ if .Values.ingress.enabled }} and
+  Ingress stay in place, so the certificate is not re-issued.{{ else }} stays in
+  place.{{ end }}
 {{ end }}
 ANYONE WHO REACHES THE URL CAN USE IT
   CyberChef has no login, and this chart adds none. If it must not be open to

cyberchef/templates/_helpers.tpl

@@ -114,3 +114,156 @@ template-chart is the reference implementation.
 1
 {{- end -}}
 {{- end -}}
+
+{{/*
+Merge a user-supplied values sub-tree onto a dict of chart defaults so that a
+null / empty override falls back to the defaults instead of erasing them.
+
+Input: dict "defaults" <dict> "given" <dict|nil> "path" <string, optional
+values path used in error messages>. Output: YAML of the merged dict (consume
+it with fromYaml).
+
+Why this exists (issue #99): Helm merges values maps recursively, but an
+override key written without children — e.g. a leftover
+
+  securityContext:
+
+after deleting its last remaining sub-key — is YAML null and replaces the
+whole default sub-tree. The container then renders with "securityContext:
+null": no readOnlyRootFilesystem, no dropped capabilities, no
+allowPrivilegeEscalation: false. The workload starts and reports healthy while
+being unhardened, so nothing points at the mistake. The same shape erases a
+probe (it disappears) or the resources block (no requests, no computed
+limits). This helper defines the opposite semantics: an empty block means
+"chart defaults apply".
+
+Rules:
+  - a nil "given" is treated as an empty dict (all defaults apply).
+  - a key whose override value is null keeps the default (nulls never delete).
+  - a key present in both as a map is merged recursively, so a partially
+    filled block only overrides the keys it actually sets.
+  - a scalar override for a key the defaults define as a map is rejected with
+    a message naming the values path, instead of failing later with a template
+    field error.
+  - any other set value wins as given, including an explicit false or 0 —
+    Helm's "default" and sprig's "mergeOverwrite" would both swallow those
+    zero values, hence the explicit kindIs "invalid" nil check.
+  - keys only present in the override are passed through unchanged.
+
+NOTE: like the helpers above, this is duplicated into every chart's
+templates/_helpers.tpl with the chart's name as define prefix, because charts
+in this repo deliberately have no dependencies.
+*/}}
+{{- define "cyberchef.defaultedDict" -}}
+{{- $defaults := .defaults | default dict -}}
+{{- $given := .given -}}
+{{- $path := .path | default "value" -}}
+{{- if kindIs "invalid" $given -}}
+{{- $given = dict -}}
+{{- end -}}
+{{- if not (kindIs "map" $given) -}}
+{{- fail (printf "%s must be a mapping or null, got %s (%v)" $path (kindOf $given) $given) -}}
+{{- end -}}
+{{- $out := deepCopy $defaults -}}
+{{- range $key, $value := $given -}}
+{{- if not (kindIs "invalid" $value) -}}
+{{- $default := index $defaults $key -}}
+{{- if and (kindIs "map" $value) (kindIs "map" $default) -}}
+{{- $_ := set $out $key (fromYaml (include "cyberchef.defaultedDict" (dict "defaults" $default "given" $value "path" (printf "%s.%s" $path $key)))) -}}
+{{- else if kindIs "map" $default -}}
+{{- fail (printf "%s.%s must be a mapping or null, got %s (%v)" $path $key (kindOf $value) $value) -}}
+{{- else -}}
+{{- $_ := set $out $key $value -}}
+{{- end -}}
+{{- end -}}
+{{- end -}}
+{{- toYaml $out -}}
+{{- end -}}
+
+{{/*
+Pick one sub-block out of a values block that may itself be null.
+
+Input: dict "block" <dict|nil> "key" <string> "path" <string>.
+Returns YAML of dict "value" <the sub-block, may be nil>, after rejecting a
+non-mapping block with a message that names the values path. Needed because
+".Values.cyberchef.securityContext" can itself be erased.
+*/}}
+{{- define "cyberchef.subBlock" -}}
+{{- $block := .block -}}
+{{- if kindIs "invalid" $block -}}
+{{- $block = dict -}}
+{{- end -}}
+{{- if not (kindIs "map" $block) -}}
+{{- fail (printf "%s must be a mapping or null, got %s (%v)" .path (kindOf $block) $block) -}}
+{{- end -}}
+{{- toYaml (dict "value" (index $block .key)) -}}
+{{- end -}}
+
+{{/*
+The effective security contexts, probes and resources (issue #99).
+
+The defaults below MUST stay in sync with the corresponding blocks in
+values.yaml, which stays the documented, user-facing place for them; this copy
+is only the fallback for the case where an override has erased the block.
+
+The probes address the container port by its name ("http"), so a rebuilt
+default probe needs no further context.
+*/}}
+{{- define "cyberchef.podSecurityContext" -}}
+{{- $given := (fromYaml (include "cyberchef.subBlock" (dict "block" . "key" "pod" "path" "cyberchef.securityContext"))).value -}}
+{{- $defaults := dict
+      "runAsNonRoot" true
+      "runAsUser" 101
+      "runAsGroup" 101 -}}
+{{- include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" $given "path" "cyberchef.securityContext.pod") -}}
+{{- end -}}
+
+{{- define "cyberchef.containerSecurityContext" -}}
+{{- $given := (fromYaml (include "cyberchef.subBlock" (dict "block" . "key" "container" "path" "cyberchef.securityContext"))).value -}}
+{{- $defaults := dict
+      "allowPrivilegeEscalation" false
+      "readOnlyRootFilesystem" true
+      "runAsNonRoot" true
+      "capabilities" (dict "drop" (list "ALL")) -}}
+{{- include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" $given "path" "cyberchef.securityContext.container") -}}
+{{- end -}}
+
+{{- define "cyberchef.livenessProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 3 -}}
+{{- include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" . "path" "cyberchef.livenessProbe") -}}
+{{- end -}}
+
+{{- define "cyberchef.readinessProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 10
+      "timeoutSeconds" 5
+      "failureThreshold" 3 -}}
+{{- include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" . "path" "cyberchef.readinessProbe") -}}
+{{- end -}}
+
+{{- define "cyberchef.startupProbe" -}}
+{{- $defaults := dict
+      "httpGet" (dict "path" "/" "port" "http")
+      "periodSeconds" 5
+      "timeoutSeconds" 5
+      "failureThreshold" 30 -}}
+{{- include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" . "path" "cyberchef.startupProbe") -}}
+{{- end -}}
+
+{{/*
+The effective resources block, fed into the resources helper above so that an
+erased "resources:" still yields the chart's requests and computed limits
+instead of a container without any resource accounting.
+*/}}
+{{- define "cyberchef.effectiveResources" -}}
+{{- $defaults := dict
+      "limitFactor" 3
+      "requests" (dict "cpu" 0.1 "memory" "512Mi" "ephemeralStorage" "10Mi") -}}
+{{- $merged := fromYaml (include "cyberchef.defaultedDict" (dict "defaults" $defaults "given" . "path" "cyberchef.resources")) -}}
+{{- include "cyberchef.resources" $merged -}}
+{{- end -}}

cyberchef/templates/cyberchef.deployment.yaml

@@ -17,7 +17,7 @@ spec:
     spec:
       automountServiceAccountToken: false
       securityContext:
-        {{- toYaml .Values.cyberchef.securityContext.pod | nindent 8 }}
+        {{- include "cyberchef.podSecurityContext" .Values.cyberchef.securityContext | nindent 8 }}
       containers:
         - name: {{ .Release.Name }}-{{ .Chart.Name }}-deployment
           image: "ghcr.io/gchq/cyberchef:{{ .Chart.AppVersion }}"
@@ -46,7 +46,7 @@ spec:
             {{- end }}
           {{- end }}
           securityContext:
-            {{- toYaml .Values.cyberchef.securityContext.container | nindent 12 }}
+            {{- include "cyberchef.containerSecurityContext" .Values.cyberchef.securityContext | nindent 12 }}
           volumeMounts:
             # nginx-unprivileged keeps its pid file and temp/cache dirs under
             # /tmp, which needs to be writable with a read-only root filesystem.
@@ -57,13 +57,13 @@ spec:
               protocol: TCP
               name: http
           livenessProbe:
-            {{- toYaml .Values.cyberchef.livenessProbe | nindent 12 }}
+            {{- include "cyberchef.livenessProbe" .Values.cyberchef.livenessProbe | nindent 12 }}
           readinessProbe:
-            {{- toYaml .Values.cyberchef.readinessProbe | nindent 12 }}
+            {{- include "cyberchef.readinessProbe" .Values.cyberchef.readinessProbe | nindent 12 }}
           startupProbe:
-            {{- toYaml .Values.cyberchef.startupProbe | nindent 12 }}
+            {{- include "cyberchef.startupProbe" .Values.cyberchef.startupProbe | nindent 12 }}
           resources:
-            {{- include "cyberchef.resources" .Values.cyberchef.resources | nindent 12 }}
+            {{- include "cyberchef.effectiveResources" .Values.cyberchef.resources | nindent 12 }}
       volumes:
         - name: tmp
           emptyDir: {}

cyberchef/templates/cyberchef.ingress.yaml

@@ -1,3 +1,4 @@
+{{- if .Values.ingress.enabled }}
 apiVersion: networking.k8s.io/v1
 kind: Ingress
 metadata:
@@ -24,3 +25,4 @@ spec:
     - hosts:
         - {{ required "A Domain/Host must be provided" .Values.ingress.domain }}
       secretName: tls-{{ .Release.Name }}-{{ .Chart.Name }}-ingress
+{{- end }}

cyberchef/values.schema.json

@@ -65,7 +65,8 @@
   },
   "definitions": {
     "resources": {
-      "type": "object",
+      "description": "May be null / empty: the chart then falls back to its default requests and computed limits (issue #99) instead of rendering a container without resource accounting.",
+      "type": ["object", "null"],
       "additionalProperties": false,
       "properties": {
         "limitFactor": {
@@ -81,7 +82,7 @@
       }
     },
     "resourceList": {
-      "type": "object",
+      "type": ["object", "null"],
       "additionalProperties": false,
       "properties": {
         "cpu": {
@@ -140,22 +141,23 @@
       }
     },
     "securityContext": {
-      "type": "object",
+      "description": "May be null / empty at any level: the chart then falls back to its hardening defaults (issue #99) instead of rendering an unhardened workload.",
+      "type": ["object", "null"],
       "additionalProperties": false,
       "properties": {
         "pod": {
-          "description": "Rendered verbatim as the pod's securityContext; kept open because the chart does not interpret it.",
-          "type": "object"
+          "description": "Merged onto the chart's pod hardening defaults and rendered as the pod's securityContext; kept open because the chart does not interpret the individual fields.",
+          "type": ["object", "null"]
         },
         "container": {
-          "description": "Rendered verbatim as the container's securityContext; kept open because the chart does not interpret it.",
-          "type": "object"
+          "description": "Merged onto the chart's container hardening defaults and rendered as the container's securityContext; kept open because the chart does not interpret the individual fields.",
+          "type": ["object", "null"]
         }
       }
     },
     "probe": {
-      "description": "Rendered verbatim as a container probe; kept open because the chart does not interpret it.",
-      "type": "object"
+      "description": "Merged onto the chart's probe defaults and rendered as a container probe; kept open because the chart does not interpret the individual fields. May be null / empty, which means the defaults apply (issue #99) rather than the probe disappearing.",
+      "type": ["object", "null"]
     }
   }
 }

cyberchef/values.yaml

@@ -59,6 +59,9 @@ cyberchef:
       ephemeralStorage: 10Mi
 
 ingress:
+  # Set to false to omit the Ingress entirely (the required domain and
+  # clusterIssuer values are then not needed either, because they are only
+  # read inside the Ingress template).
   enabled: true
   clusterIssuer: null
   domain: null