diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/artifacthub-pkg.yml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/artifacthub-pkg.yml new file mode 100644 index 000000000..306675130 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/artifacthub-pkg.yml @@ -0,0 +1,22 @@ +version: 1.1.0 +name: k8spsphostnetworkingports +displayName: Host Networking Ports +createdAt: "2024-06-04T00:04:23Z" +description: Controls usage of host network namespace by pod containers. Specific ports must be specified. Corresponds to the `hostNetwork` and `hostPorts` fields in a PodSecurityPolicy. For more information, see https://kubernetes.io/docs/concepts/policy/pod-security-policy/#host-namespaces +digest: b4b275420d181ab6a007360e37bdda6356b0d2692982f192fbb2aa37d18bbe3b +license: Apache-2.0 +homeURL: https://open-policy-agent.github.io/gatekeeper-library/website/host-network-ports +keywords: + - gatekeeper + - open-policy-agent + - policies +readme: |- + # Host Networking Ports + Controls usage of host network namespace by pod containers. Specific ports must be specified. Corresponds to the `hostNetwork` and `hostPorts` fields in a PodSecurityPolicy. For more information, see https://kubernetes.io/docs/concepts/policy/pod-security-policy/#host-namespaces +install: |- + ### Usage + ```shell + kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper-library/master/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/template.yaml + ``` +provider: + name: Gatekeeper Library diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/kustomization.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/kustomization.yaml new file mode 100644 index 000000000..7d70d11b7 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/kustomization.yaml @@ -0,0 +1,2 @@ +resources: + - template.yaml diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint.yaml new file mode 100644 index 000000000..fcbc5d805 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint.yaml @@ -0,0 +1,13 @@ +apiVersion: constraints.gatekeeper.sh/v1beta1 +kind: K8sPSPHostNetworkingPorts +metadata: + name: psp-host-network-ports +spec: + match: + kinds: + - apiGroups: [""] + kinds: ["Pod"] + parameters: + hostNetwork: true + min: 80 + max: 9000 diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint_block_host_network.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint_block_host_network.yaml new file mode 100644 index 000000000..7d468802f --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/constraint_block_host_network.yaml @@ -0,0 +1,11 @@ +apiVersion: constraints.gatekeeper.sh/v1beta1 +kind: K8sPSPHostNetworkingPorts +metadata: + name: psp-host-network +spec: + match: + kinds: + - apiGroups: [""] + kinds: ["Pod"] + parameters: + hostNetwork: false \ No newline at end of file diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/disallowed_ephemeral.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/disallowed_ephemeral.yaml new file mode 100644 index 000000000..7a4fa3114 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/disallowed_ephemeral.yaml @@ -0,0 +1,14 @@ +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-disallowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: true + ephemeralContainers: + - name: nginx + image: nginx + ports: + - containerPort: 9001 + hostPort: 9001 diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_allowed.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_allowed.yaml new file mode 100644 index 000000000..08b321fe5 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_allowed.yaml @@ -0,0 +1,14 @@ +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-allowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: false + containers: + - name: nginx + image: nginx + ports: + - containerPort: 9000 + hostPort: 80 diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_disallowed.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_disallowed.yaml new file mode 100644 index 000000000..9a496cd60 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/example_disallowed.yaml @@ -0,0 +1,14 @@ +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-disallowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: true + containers: + - name: nginx + image: nginx + ports: + - containerPort: 9001 + hostPort: 9001 diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/update.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/update.yaml new file mode 100644 index 000000000..231096430 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/samples/psp-host-network-ports/update.yaml @@ -0,0 +1,19 @@ +kind: AdmissionReview +apiVersion: admission.k8s.io/v1beta1 +request: + operation: "UPDATE" + object: + apiVersion: v1 + kind: Pod + metadata: + name: nginx-host-networking-ports-disallowed + labels: + app: nginx-host-networking-ports + spec: + hostNetwork: true + containers: + - name: nginx + image: nginx + ports: + - containerPort: 9001 + hostPort: 9001 diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/suite.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/suite.yaml new file mode 100644 index 000000000..bb7e60a56 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/suite.yaml @@ -0,0 +1,45 @@ +kind: Suite +apiVersion: test.gatekeeper.sh/v1alpha1 +metadata: + name: host-network-ports +tests: +- name: use-of-host-networking-ports-blocked + template: template.yaml + constraint: samples/psp-host-network-ports/constraint.yaml + cases: + - name: example-disallowed + object: samples/psp-host-network-ports/example_disallowed.yaml + assertions: + - violations: yes + - name: example-allowed + object: samples/psp-host-network-ports/example_allowed.yaml + assertions: + - violations: no + - name: disallowed-ephemeral + object: samples/psp-host-network-ports/disallowed_ephemeral.yaml + assertions: + - violations: yes + - name: update + object: samples/psp-host-network-ports/update.yaml + assertions: + - violations: no +- name: use-of-host-network-blocked + template: template.yaml + constraint: samples/psp-host-network-ports/constraint_block_host_network.yaml + cases: + - name: example-disallowed + object: samples/psp-host-network-ports/example_disallowed.yaml + assertions: + - violations: yes + - name: example-allowed + object: samples/psp-host-network-ports/example_allowed.yaml + assertions: + - violations: no + - name: disallowed-ephemeral + object: samples/psp-host-network-ports/disallowed_ephemeral.yaml + assertions: + - violations: yes + - name: update + object: samples/psp-host-network-ports/update.yaml + assertions: + - violations: no diff --git a/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/template.yaml b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/template.yaml new file mode 100644 index 000000000..d697e74e6 --- /dev/null +++ b/artifacthub/library/pod-security-policy/host-network-ports/1.1.0/template.yaml @@ -0,0 +1,156 @@ +apiVersion: templates.gatekeeper.sh/v1 +kind: ConstraintTemplate +metadata: + name: k8spsphostnetworkingports + annotations: + metadata.gatekeeper.sh/title: "Host Networking Ports" + metadata.gatekeeper.sh/version: 1.1.0 + description: >- + Controls usage of host network namespace by pod containers. Specific + ports must be specified. Corresponds to the `hostNetwork` and + `hostPorts` fields in a PodSecurityPolicy. For more information, see + https://kubernetes.io/docs/concepts/policy/pod-security-policy/#host-namespaces +spec: + crd: + spec: + names: + kind: K8sPSPHostNetworkingPorts + validation: + # Schema for the `parameters` field + openAPIV3Schema: + type: object + description: >- + Controls usage of host network namespace by pod containers. Specific + ports must be specified. Corresponds to the `hostNetwork` and + `hostPorts` fields in a PodSecurityPolicy. For more information, see + https://kubernetes.io/docs/concepts/policy/pod-security-policy/#host-namespaces + properties: + exemptImages: + description: >- + Any container that uses an image that matches an entry in this list will be excluded + from enforcement. Prefix-matching can be signified with `*`. For example: `my-image-*`. + + It is recommended that users use the fully-qualified Docker image name (e.g. start with a domain name) + in order to avoid unexpectedly exempting images from an untrusted repository. + type: array + items: + type: string + hostNetwork: + description: "Determines if the policy allows the use of HostNetwork in the pod spec." + type: boolean + min: + description: "The start of the allowed port range, inclusive." + type: integer + max: + description: "The end of the allowed port range, inclusive." + type: integer + targets: + - target: admission.k8s.gatekeeper.sh + code: + - engine: K8sNativeValidation + source: + variables: + - name: containers + expression: 'has(variables.anyObject.spec.containers) ? variables.anyObject.spec.containers : []' + - name: initContainers + expression: 'has(variables.anyObject.spec.initContainers) ? variables.anyObject.spec.initContainers : []' + - name: ephemeralContainers + expression: 'has(variables.anyObject.spec.ephemeralContainers) ? variables.anyObject.spec.ephemeralContainers : []' + - name: exemptImagePrefixes + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, image.endsWith("*")).map(image, string(image).replace("*", "")) + - name: exemptImageExplicit + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, !image.endsWith("*")) + - name: exemptImages + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + container.image in variables.exemptImageExplicit || + variables.exemptImagePrefixes.exists(exemption, string(container.image).startsWith(exemption))) + - name: badContainers + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + !(container.image in variables.exemptImages) && + ( + (!has(variables.params.hostNetwork) || !variables.params.hostNetwork ? (has(variables.anyObject.spec.hostNetwork) && variables.anyObject.spec.hostNetwork) : false) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.min) && port.hostPort < variables.params.min)) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.max) && port.hostPort > variables.params.max)) + ) + ) + validations: + - expression: '(has(request.operation) && request.operation == "UPDATE") || size(variables.badContainers) == 0' + messageExpression: '"The specified hostNetwork and hostPort are not allowed, pod: " + variables.anyObject.metadata.name + ". Allowed values: " + variables.params' + - engine: Rego + source: + rego: | + package k8spsphostnetworkingports + + import data.lib.exclude_update.is_update + import data.lib.exempt_container.is_exempt + + violation[{"msg": msg, "details": {}}] { + # spec.hostNetwork field is immutable. + not is_update(input.review) + + input_share_hostnetwork(input.review.object) + msg := sprintf("The specified hostNetwork and hostPort are not allowed, pod: %v. Allowed values: %v", [input.review.object.metadata.name, input.parameters]) + } + + input_share_hostnetwork(o) { + not input.parameters.hostNetwork + o.spec.hostNetwork + } + + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort < input.parameters.min + } + + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort > input.parameters.max + } + + input_containers[c] { + c := input.review.object.spec.containers[_] + not is_exempt(c) + } + + input_containers[c] { + c := input.review.object.spec.initContainers[_] + not is_exempt(c) + } + + input_containers[c] { + c := input.review.object.spec.ephemeralContainers[_] + not is_exempt(c) + } + libs: + - | + package lib.exclude_update + + is_update(review) { + review.operation == "UPDATE" + } + - | + package lib.exempt_container + + is_exempt(container) { + exempt_images := object.get(object.get(input, "parameters", {}), "exemptImages", []) + img := container.image + exemption := exempt_images[_] + _matches_exemption(img, exemption) + } + + _matches_exemption(img, exemption) { + not endswith(exemption, "*") + exemption == img + } + + _matches_exemption(img, exemption) { + endswith(exemption, "*") + prefix := trim_suffix(exemption, "*") + startswith(img, prefix) + } diff --git a/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/constraint_block_host_network.yaml b/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/constraint_block_host_network.yaml new file mode 100644 index 000000000..7d468802f --- /dev/null +++ b/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/constraint_block_host_network.yaml @@ -0,0 +1,11 @@ +apiVersion: constraints.gatekeeper.sh/v1beta1 +kind: K8sPSPHostNetworkingPorts +metadata: + name: psp-host-network +spec: + match: + kinds: + - apiGroups: [""] + kinds: ["Pod"] + parameters: + hostNetwork: false \ No newline at end of file diff --git a/library/pod-security-policy/host-network-ports/suite.yaml b/library/pod-security-policy/host-network-ports/suite.yaml index 710df69eb..bb7e60a56 100644 --- a/library/pod-security-policy/host-network-ports/suite.yaml +++ b/library/pod-security-policy/host-network-ports/suite.yaml @@ -23,3 +23,23 @@ tests: object: samples/psp-host-network-ports/update.yaml assertions: - violations: no +- name: use-of-host-network-blocked + template: template.yaml + constraint: samples/psp-host-network-ports/constraint_block_host_network.yaml + cases: + - name: example-disallowed + object: samples/psp-host-network-ports/example_disallowed.yaml + assertions: + - violations: yes + - name: example-allowed + object: samples/psp-host-network-ports/example_allowed.yaml + assertions: + - violations: no + - name: disallowed-ephemeral + object: samples/psp-host-network-ports/disallowed_ephemeral.yaml + assertions: + - violations: yes + - name: update + object: samples/psp-host-network-ports/update.yaml + assertions: + - violations: no diff --git a/library/pod-security-policy/host-network-ports/template.yaml b/library/pod-security-policy/host-network-ports/template.yaml index 0f04aae03..d697e74e6 100644 --- a/library/pod-security-policy/host-network-ports/template.yaml +++ b/library/pod-security-policy/host-network-ports/template.yaml @@ -4,7 +4,7 @@ metadata: name: k8spsphostnetworkingports annotations: metadata.gatekeeper.sh/title: "Host Networking Ports" - metadata.gatekeeper.sh/version: 1.0.2 + metadata.gatekeeper.sh/version: 1.1.0 description: >- Controls usage of host network namespace by pod containers. Specific ports must be specified. Corresponds to the `hostNetwork` and @@ -46,73 +46,111 @@ spec: type: integer targets: - target: admission.k8s.gatekeeper.sh - rego: | - package k8spsphostnetworkingports + code: + - engine: K8sNativeValidation + source: + variables: + - name: containers + expression: 'has(variables.anyObject.spec.containers) ? variables.anyObject.spec.containers : []' + - name: initContainers + expression: 'has(variables.anyObject.spec.initContainers) ? variables.anyObject.spec.initContainers : []' + - name: ephemeralContainers + expression: 'has(variables.anyObject.spec.ephemeralContainers) ? variables.anyObject.spec.ephemeralContainers : []' + - name: exemptImagePrefixes + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, image.endsWith("*")).map(image, string(image).replace("*", "")) + - name: exemptImageExplicit + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, !image.endsWith("*")) + - name: exemptImages + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + container.image in variables.exemptImageExplicit || + variables.exemptImagePrefixes.exists(exemption, string(container.image).startsWith(exemption))) + - name: badContainers + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + !(container.image in variables.exemptImages) && + ( + (!has(variables.params.hostNetwork) || !variables.params.hostNetwork ? (has(variables.anyObject.spec.hostNetwork) && variables.anyObject.spec.hostNetwork) : false) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.min) && port.hostPort < variables.params.min)) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.max) && port.hostPort > variables.params.max)) + ) + ) + validations: + - expression: '(has(request.operation) && request.operation == "UPDATE") || size(variables.badContainers) == 0' + messageExpression: '"The specified hostNetwork and hostPort are not allowed, pod: " + variables.anyObject.metadata.name + ". Allowed values: " + variables.params' + - engine: Rego + source: + rego: | + package k8spsphostnetworkingports - import data.lib.exclude_update.is_update - import data.lib.exempt_container.is_exempt + import data.lib.exclude_update.is_update + import data.lib.exempt_container.is_exempt - violation[{"msg": msg, "details": {}}] { - # spec.hostNetwork field is immutable. - not is_update(input.review) + violation[{"msg": msg, "details": {}}] { + # spec.hostNetwork field is immutable. + not is_update(input.review) - input_share_hostnetwork(input.review.object) - msg := sprintf("The specified hostNetwork and hostPort are not allowed, pod: %v. Allowed values: %v", [input.review.object.metadata.name, input.parameters]) - } + input_share_hostnetwork(input.review.object) + msg := sprintf("The specified hostNetwork and hostPort are not allowed, pod: %v. Allowed values: %v", [input.review.object.metadata.name, input.parameters]) + } - input_share_hostnetwork(o) { - not input.parameters.hostNetwork - o.spec.hostNetwork - } + input_share_hostnetwork(o) { + not input.parameters.hostNetwork + o.spec.hostNetwork + } - input_share_hostnetwork(_) { - hostPort := input_containers[_].ports[_].hostPort - hostPort < input.parameters.min - } + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort < input.parameters.min + } - input_share_hostnetwork(_) { - hostPort := input_containers[_].ports[_].hostPort - hostPort > input.parameters.max - } + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort > input.parameters.max + } - input_containers[c] { - c := input.review.object.spec.containers[_] - not is_exempt(c) - } + input_containers[c] { + c := input.review.object.spec.containers[_] + not is_exempt(c) + } - input_containers[c] { - c := input.review.object.spec.initContainers[_] - not is_exempt(c) - } + input_containers[c] { + c := input.review.object.spec.initContainers[_] + not is_exempt(c) + } - input_containers[c] { - c := input.review.object.spec.ephemeralContainers[_] - not is_exempt(c) - } - libs: - - | - package lib.exclude_update + input_containers[c] { + c := input.review.object.spec.ephemeralContainers[_] + not is_exempt(c) + } + libs: + - | + package lib.exclude_update - is_update(review) { - review.operation == "UPDATE" - } - - | - package lib.exempt_container + is_update(review) { + review.operation == "UPDATE" + } + - | + package lib.exempt_container - is_exempt(container) { - exempt_images := object.get(object.get(input, "parameters", {}), "exemptImages", []) - img := container.image - exemption := exempt_images[_] - _matches_exemption(img, exemption) - } + is_exempt(container) { + exempt_images := object.get(object.get(input, "parameters", {}), "exemptImages", []) + img := container.image + exemption := exempt_images[_] + _matches_exemption(img, exemption) + } - _matches_exemption(img, exemption) { - not endswith(exemption, "*") - exemption == img - } + _matches_exemption(img, exemption) { + not endswith(exemption, "*") + exemption == img + } - _matches_exemption(img, exemption) { - endswith(exemption, "*") - prefix := trim_suffix(exemption, "*") - startswith(img, prefix) - } + _matches_exemption(img, exemption) { + endswith(exemption, "*") + prefix := trim_suffix(exemption, "*") + startswith(img, prefix) + } diff --git a/src/pod-security-policy/host-network-ports/constraint.tmpl b/src/pod-security-policy/host-network-ports/constraint.tmpl index c8fd7a131..e6f005ef9 100644 --- a/src/pod-security-policy/host-network-ports/constraint.tmpl +++ b/src/pod-security-policy/host-network-ports/constraint.tmpl @@ -4,7 +4,7 @@ metadata: name: k8spsphostnetworkingports annotations: metadata.gatekeeper.sh/title: "Host Networking Ports" - metadata.gatekeeper.sh/version: 1.0.2 + metadata.gatekeeper.sh/version: 1.1.0 description: >- Controls usage of host network namespace by pod containers. Specific ports must be specified. Corresponds to the `hostNetwork` and @@ -46,10 +46,16 @@ spec: type: integer targets: - target: admission.k8s.gatekeeper.sh - rego: | -{{ file.Read "src/pod-security-policy/host-network-ports/src.rego" | strings.Indent 8 | strings.TrimSuffix "\n" }} - libs: - - | -{{ file.Read "src/pod-security-policy/host-network-ports/lib_exclude_update.rego" | strings.Indent 10 | strings.TrimSuffix "\n" }} - - | -{{ file.Read "src/pod-security-policy/host-network-ports/lib_exempt_container.rego" | strings.Indent 10 | strings.TrimSuffix "\n" }} + code: + - engine: K8sNativeValidation + source: +{{ file.Read "src/pod-security-policy/host-network-ports/src.cel" | strings.Indent 10 | strings.TrimSuffix "\n" }} + - engine: Rego + source: + rego: | +{{ file.Read "src/pod-security-policy/host-network-ports/src.rego" | strings.Indent 12 | strings.TrimSuffix "\n" }} + libs: + - | +{{ file.Read "src/pod-security-policy/host-network-ports/lib_exclude_update.rego" | strings.Indent 14 | strings.TrimSuffix "\n" }} + - | +{{ file.Read "src/pod-security-policy/host-network-ports/lib_exempt_container.rego" | strings.Indent 14 | strings.TrimSuffix "\n" }} diff --git a/src/pod-security-policy/host-network-ports/src.cel b/src/pod-security-policy/host-network-ports/src.cel new file mode 100644 index 000000000..eb60e5c16 --- /dev/null +++ b/src/pod-security-policy/host-network-ports/src.cel @@ -0,0 +1,33 @@ +variables: +- name: containers + expression: 'has(variables.anyObject.spec.containers) ? variables.anyObject.spec.containers : []' +- name: initContainers + expression: 'has(variables.anyObject.spec.initContainers) ? variables.anyObject.spec.initContainers : []' +- name: ephemeralContainers + expression: 'has(variables.anyObject.spec.ephemeralContainers) ? variables.anyObject.spec.ephemeralContainers : []' +- name: exemptImagePrefixes + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, image.endsWith("*")).map(image, string(image).replace("*", "")) +- name: exemptImageExplicit + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, !image.endsWith("*")) +- name: exemptImages + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + container.image in variables.exemptImageExplicit || + variables.exemptImagePrefixes.exists(exemption, string(container.image).startsWith(exemption))) +- name: badContainers + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + !(container.image in variables.exemptImages) && + ( + (!has(variables.params.hostNetwork) || !variables.params.hostNetwork ? (has(variables.anyObject.spec.hostNetwork) && variables.anyObject.spec.hostNetwork) : false) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.min) && port.hostPort < variables.params.min)) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.max) && port.hostPort > variables.params.max)) + ) + ) +validations: +- expression: '(has(request.operation) && request.operation == "UPDATE") || size(variables.badContainers) == 0' + messageExpression: '"The specified hostNetwork and hostPort are not allowed, pod: " + variables.anyObject.metadata.name + ". Allowed values: " + variables.params' \ No newline at end of file diff --git a/website/docs/validation/host-network-ports.md b/website/docs/validation/host-network-ports.md index 1e7928894..1824b5c36 100644 --- a/website/docs/validation/host-network-ports.md +++ b/website/docs/validation/host-network-ports.md @@ -16,7 +16,7 @@ metadata: name: k8spsphostnetworkingports annotations: metadata.gatekeeper.sh/title: "Host Networking Ports" - metadata.gatekeeper.sh/version: 1.0.2 + metadata.gatekeeper.sh/version: 1.1.0 description: >- Controls usage of host network namespace by pod containers. Specific ports must be specified. Corresponds to the `hostNetwork` and @@ -58,76 +58,114 @@ spec: type: integer targets: - target: admission.k8s.gatekeeper.sh - rego: | - package k8spsphostnetworkingports - - import data.lib.exclude_update.is_update - import data.lib.exempt_container.is_exempt - - violation[{"msg": msg, "details": {}}] { - # spec.hostNetwork field is immutable. - not is_update(input.review) - - input_share_hostnetwork(input.review.object) - msg := sprintf("The specified hostNetwork and hostPort are not allowed, pod: %v. Allowed values: %v", [input.review.object.metadata.name, input.parameters]) - } - - input_share_hostnetwork(o) { - not input.parameters.hostNetwork - o.spec.hostNetwork - } - - input_share_hostnetwork(_) { - hostPort := input_containers[_].ports[_].hostPort - hostPort < input.parameters.min - } - - input_share_hostnetwork(_) { - hostPort := input_containers[_].ports[_].hostPort - hostPort > input.parameters.max - } - - input_containers[c] { - c := input.review.object.spec.containers[_] - not is_exempt(c) - } - - input_containers[c] { - c := input.review.object.spec.initContainers[_] - not is_exempt(c) - } - - input_containers[c] { - c := input.review.object.spec.ephemeralContainers[_] - not is_exempt(c) - } - libs: - - | - package lib.exclude_update - - is_update(review) { - review.operation == "UPDATE" - } - - | - package lib.exempt_container - - is_exempt(container) { - exempt_images := object.get(object.get(input, "parameters", {}), "exemptImages", []) - img := container.image - exemption := exempt_images[_] - _matches_exemption(img, exemption) - } - - _matches_exemption(img, exemption) { - not endswith(exemption, "*") - exemption == img - } - - _matches_exemption(img, exemption) { - endswith(exemption, "*") - prefix := trim_suffix(exemption, "*") - startswith(img, prefix) - } + code: + - engine: K8sNativeValidation + source: + variables: + - name: containers + expression: 'has(variables.anyObject.spec.containers) ? variables.anyObject.spec.containers : []' + - name: initContainers + expression: 'has(variables.anyObject.spec.initContainers) ? variables.anyObject.spec.initContainers : []' + - name: ephemeralContainers + expression: 'has(variables.anyObject.spec.ephemeralContainers) ? variables.anyObject.spec.ephemeralContainers : []' + - name: exemptImagePrefixes + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, image.endsWith("*")).map(image, string(image).replace("*", "")) + - name: exemptImageExplicit + expression: | + !has(variables.params.exemptImages) ? [] : + variables.params.exemptImages.filter(image, !image.endsWith("*")) + - name: exemptImages + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + container.image in variables.exemptImageExplicit || + variables.exemptImagePrefixes.exists(exemption, string(container.image).startsWith(exemption))) + - name: badContainers + expression: | + (variables.containers + variables.initContainers + variables.ephemeralContainers).filter(container, + !(container.image in variables.exemptImages) && + ( + (!has(variables.params.hostNetwork) || !variables.params.hostNetwork ? (has(variables.anyObject.spec.hostNetwork) && variables.anyObject.spec.hostNetwork) : false) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.min) && port.hostPort < variables.params.min)) || + (container.ports.all(port, has(port.hostPort) && has(variables.params.max) && port.hostPort > variables.params.max)) + ) + ) + validations: + - expression: '(has(request.operation) && request.operation == "UPDATE") || size(variables.badContainers) == 0' + messageExpression: '"The specified hostNetwork and hostPort are not allowed, pod: " + variables.anyObject.metadata.name + ". Allowed values: " + variables.params' + - engine: Rego + source: + rego: | + package k8spsphostnetworkingports + + import data.lib.exclude_update.is_update + import data.lib.exempt_container.is_exempt + + violation[{"msg": msg, "details": {}}] { + # spec.hostNetwork field is immutable. + not is_update(input.review) + + input_share_hostnetwork(input.review.object) + msg := sprintf("The specified hostNetwork and hostPort are not allowed, pod: %v. Allowed values: %v", [input.review.object.metadata.name, input.parameters]) + } + + input_share_hostnetwork(o) { + not input.parameters.hostNetwork + o.spec.hostNetwork + } + + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort < input.parameters.min + } + + input_share_hostnetwork(_) { + hostPort := input_containers[_].ports[_].hostPort + hostPort > input.parameters.max + } + + input_containers[c] { + c := input.review.object.spec.containers[_] + not is_exempt(c) + } + + input_containers[c] { + c := input.review.object.spec.initContainers[_] + not is_exempt(c) + } + + input_containers[c] { + c := input.review.object.spec.ephemeralContainers[_] + not is_exempt(c) + } + libs: + - | + package lib.exclude_update + + is_update(review) { + review.operation == "UPDATE" + } + - | + package lib.exempt_container + + is_exempt(container) { + exempt_images := object.get(object.get(input, "parameters", {}), "exemptImages", []) + img := container.image + exemption := exempt_images[_] + _matches_exemption(img, exemption) + } + + _matches_exemption(img, exemption) { + not endswith(exemption, "*") + exemption == img + } + + _matches_exemption(img, exemption) { + endswith(exemption, "*") + prefix := trim_suffix(exemption, "*") + startswith(img, prefix) + } ``` @@ -253,4 +291,118 @@ kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper- +
+use-of-host-network-blocked + +
+constraint + +```yaml +apiVersion: constraints.gatekeeper.sh/v1beta1 +kind: K8sPSPHostNetworkingPorts +metadata: + name: psp-host-network +spec: + match: + kinds: + - apiGroups: [""] + kinds: ["Pod"] + parameters: + hostNetwork: false +``` + +Usage + +```shell +kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper-library/master/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/constraint_block_host_network.yaml +``` + +
+ +
+example-disallowed + +```yaml +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-disallowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: true + containers: + - name: nginx + image: nginx + ports: + - containerPort: 9001 + hostPort: 9001 + +``` + +Usage + +```shell +kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper-library/master/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/example_disallowed.yaml +``` + +
+
+example-allowed + +```yaml +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-allowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: false + containers: + - name: nginx + image: nginx + ports: + - containerPort: 9000 + hostPort: 80 + +``` + +Usage + +```shell +kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper-library/master/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/example_allowed.yaml +``` + +
+
+disallowed-ephemeral + +```yaml +apiVersion: v1 +kind: Pod +metadata: + name: nginx-host-networking-ports-disallowed + labels: + app: nginx-host-networking-ports +spec: + hostNetwork: true + ephemeralContainers: + - name: nginx + image: nginx + ports: + - containerPort: 9001 + hostPort: 9001 + +``` + +Usage + +```shell +kubectl apply -f https://raw.githubusercontent.com/open-policy-agent/gatekeeper-library/master/library/pod-security-policy/host-network-ports/samples/psp-host-network-ports/disallowed_ephemeral.yaml +``` + +
+ +
\ No newline at end of file