From a800ed094b40aac9e73ac5115bf8506ef53c1db1 Mon Sep 17 00:00:00 2001 From: Jonas Kongslund Date: Sun, 21 Jan 2018 14:34:37 +0400 Subject: [PATCH] Added support for webhook authentication/authorization on the secure kubelet endpoint --- .../cluster_roles/tasks/main.yml | 46 +++++++++++++++++++ .../templates/node-webhook-cr.yml.j2 | 19 ++++++++ .../templates/node-webhook-crb.yml.j2 | 17 +++++++ .../node/templates/kubelet.kubeadm.env.j2 | 3 ++ .../node/templates/kubelet.standard.env.j2 | 6 +++ roles/kubespray-defaults/defaults/main.yaml | 6 +++ 6 files changed, 97 insertions(+) create mode 100644 roles/kubernetes-apps/cluster_roles/templates/node-webhook-cr.yml.j2 create mode 100644 roles/kubernetes-apps/cluster_roles/templates/node-webhook-crb.yml.j2 diff --git a/roles/kubernetes-apps/cluster_roles/tasks/main.yml b/roles/kubernetes-apps/cluster_roles/tasks/main.yml index 5bf670949..b58670c0f 100644 --- a/roles/kubernetes-apps/cluster_roles/tasks/main.yml +++ b/roles/kubernetes-apps/cluster_roles/tasks/main.yml @@ -29,6 +29,52 @@ - rbac_enabled - node_crb_manifest.changed +- name: Kubernetes Apps | Add webhook ClusterRole that grants access to proxy, stats, log, spec, and metrics on a kubelet + template: + src: "node-webhook-cr.yml.j2" + dest: "{{ kube_config_dir }}/node-webhook-cr.yml" + register: node_webhook_cr_manifest + when: + - rbac_enabled + - kubelet_authorization_mode_webhook + tags: node-webhook + +- name: Apply webhook ClusterRole + kube: + name: "system:node-webhook" + kubectl: "{{bin_dir}}/kubectl" + resource: "clusterrole" + filename: "{{ kube_config_dir }}/node-webhook-cr.yml" + state: latest + when: + - rbac_enabled + - kubelet_authorization_mode_webhook + - node_webhook_cr_manifest.changed + tags: node-webhook + +- name: Kubernetes Apps | Add ClusterRoleBinding for system:nodes to webhook ClusterRole + template: + src: "node-webhook-crb.yml.j2" + dest: "{{ kube_config_dir }}/node-webhook-crb.yml" + register: node_webhook_crb_manifest + when: + - rbac_enabled + - kubelet_authorization_mode_webhook + tags: node-webhook + +- name: Grant system:nodes the webhook ClusterRole + kube: + name: "system:node-webhook" + kubectl: "{{bin_dir}}/kubectl" + resource: "clusterrolebinding" + filename: "{{ kube_config_dir }}/node-webhook-crb.yml" + state: latest + when: + - rbac_enabled + - kubelet_authorization_mode_webhook + - node_webhook_crb_manifest.changed + tags: node-webhook + # This is not a cluster role, but should be run after kubeconfig is set on master - name: Write kube system namespace manifest template: diff --git a/roles/kubernetes-apps/cluster_roles/templates/node-webhook-cr.yml.j2 b/roles/kubernetes-apps/cluster_roles/templates/node-webhook-cr.yml.j2 new file mode 100644 index 000000000..3f32c2599 --- /dev/null +++ b/roles/kubernetes-apps/cluster_roles/templates/node-webhook-cr.yml.j2 @@ -0,0 +1,19 @@ +apiVersion: rbac.authorization.k8s.io/v1beta1 +kind: ClusterRole +metadata: + annotations: + rbac.authorization.kubernetes.io/autoupdate: "true" + labels: + kubernetes.io/bootstrapping: rbac-defaults + name: system:node-webhook +rules: + - apiGroups: + - "" + resources: + - nodes/proxy + - nodes/stats + - nodes/log + - nodes/spec + - nodes/metrics + verbs: + - "*" \ No newline at end of file diff --git a/roles/kubernetes-apps/cluster_roles/templates/node-webhook-crb.yml.j2 b/roles/kubernetes-apps/cluster_roles/templates/node-webhook-crb.yml.j2 new file mode 100644 index 000000000..68aed5cb5 --- /dev/null +++ b/roles/kubernetes-apps/cluster_roles/templates/node-webhook-crb.yml.j2 @@ -0,0 +1,17 @@ +--- +apiVersion: rbac.authorization.k8s.io/v1 +kind: ClusterRoleBinding +metadata: + annotations: + rbac.authorization.kubernetes.io/autoupdate: "true" + labels: + kubernetes.io/bootstrapping: rbac-defaults + name: system:node-webhook +roleRef: + apiGroup: rbac.authorization.k8s.io + kind: ClusterRole + name: system:node-webhook +subjects: +- apiGroup: rbac.authorization.k8s.io + kind: Group + name: system:nodes diff --git a/roles/kubernetes/node/templates/kubelet.kubeadm.env.j2 b/roles/kubernetes/node/templates/kubelet.kubeadm.env.j2 index e49b15f48..93297accd 100644 --- a/roles/kubernetes/node/templates/kubelet.kubeadm.env.j2 +++ b/roles/kubernetes/node/templates/kubelet.kubeadm.env.j2 @@ -20,6 +20,9 @@ KUBELET_HOSTNAME="--hostname-override={{ kube_override_hostname }}" {% if kube_version | version_compare('v1.8', '<') %} --require-kubeconfig \ {% endif %} +{% if kubelet_authentication_token_webhook %} +--authentication-token-webhook \ +{% endif %} --authorization-mode=Webhook \ --client-ca-file={{ kube_cert_dir }}/ca.crt \ --pod-manifest-path={{ kube_manifest_dir }} \ diff --git a/roles/kubernetes/node/templates/kubelet.standard.env.j2 b/roles/kubernetes/node/templates/kubelet.standard.env.j2 index cb7d83d35..5c112c179 100644 --- a/roles/kubernetes/node/templates/kubelet.standard.env.j2 +++ b/roles/kubernetes/node/templates/kubelet.standard.env.j2 @@ -33,6 +33,12 @@ KUBELET_HOSTNAME="--hostname-override={{ kube_override_hostname }}" {% else %} --fail-swap-on={{ kubelet_fail_swap_on|default(true)}} \ {% endif %} +{% if kubelet_authentication_token_webhook %} +--authentication-token-webhook \ +{% endif %} +{% if kubelet_authorization_mode_webhook %} +--authorization-mode=Webhook \ +{% endif %} --enforce-node-allocatable={{ kubelet_enforce_node_allocatable }} {% endif %}{% endset %} {# DNS settings for kubelet #} diff --git a/roles/kubespray-defaults/defaults/main.yaml b/roles/kubespray-defaults/defaults/main.yaml index 8622d919f..692c2e698 100644 --- a/roles/kubespray-defaults/defaults/main.yaml +++ b/roles/kubespray-defaults/defaults/main.yaml @@ -197,6 +197,12 @@ openstack_lbaas_monitor_max_retries: "3" authorization_modes: ['Node', 'RBAC'] rbac_enabled: "{{ 'RBAC' in authorization_modes or kubeadm_enabled }}" +# When enabled, API bearer tokens (including service account tokens) can be used to authenticate to the kubelet’s HTTPS endpoint +kubelet_authentication_token_webhook: false + +# When enabled, access to the kubelet API requires authorization by delegation to the API server +kubelet_authorization_mode_webhook: false + ## List of key=value pairs that describe feature gates for ## the k8s cluster. kube_feature_gates: