Adds support for Multus (multiple interfaces) CNI plugin (#3166)

* Adds support for Multus (multiple interfaces) CNI plugin

Multus is a latin word for "Multi". As the name suggests, it acts as a
Multi plugin in Kubernetes and provides multiple network interface
support in a pod. Multus uses the concept of invoking delegates by
grouping multiple plugins into delegates and invoking them in the
sequential order of the CNI configuration file provided in json format.

* Change CNI version (0.1.0->0.3.1) of Contiv to be compatible with Multus

roles/network_plugin/multus/defaults/main.yml

@@ -0,0 +1,7 @@
+---
+multus_conf_file: "auto"
+multus_cni_conf_dir_host: "/etc/cni/net.d"
+multus_cni_bin_dir_host: "/opt/cni/bin"
+multus_cni_conf_dir: "{{ ('/host',  multus_cni_conf_dir_host) | join }}"
+multus_cni_bin_dir: "{{ ('/host', multus_cni_bin_dir_host) | join }}"
+multus_kubeconfig_file_host: "{{ (multus_cni_conf_dir_host, '/multus.d/multus.kubeconfig') | join }}"

roles/network_plugin/multus/files/multus-clusterrole.yml

@@ -0,0 +1,16 @@
+---
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1beta1
+metadata:
+  name: multus
+rules:
+- apiGroups:
+  - '*'
+  resources:
+  - '*'
+  verbs:
+  - '*'
+- nonResourceURLs:
+  - '*'
+  verbs:
+  - '*'

roles/network_plugin/multus/files/multus-clusterrolebinding.yml

@@ -0,0 +1,13 @@
+---
+kind: ClusterRoleBinding
+apiVersion: rbac.authorization.k8s.io/v1beta1
+metadata:
+  name: multus
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: multus
+subjects:
+- kind: ServiceAccount
+  name: multus
+  namespace: kube-system

roles/network_plugin/multus/files/multus-crd.yml

@@ -0,0 +1,22 @@
+---
+kind: CustomResourceDefinition
+apiVersion: apiextensions.k8s.io/v1beta1
+metadata:
+  name: network-attachment-definitions.k8s.cni.cncf.io
+spec:
+  group: k8s.cni.cncf.io
+  version: v1
+  scope: Namespaced
+  names:
+    plural: network-attachment-definitions
+    singular: network-attachment-definition
+    kind: NetworkAttachmentDefinition
+    shortNames:
+    - net-attach-def
+  validation:
+    openAPIV3Schema:
+      properties:
+        spec:
+          properties:
+            config:
+              type: string

roles/network_plugin/multus/files/multus-serviceaccount.yml

@@ -0,0 +1,6 @@
+---
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: multus
+  namespace: kube-system

roles/network_plugin/multus/tasks/main.yml

@@ -0,0 +1,19 @@
+---
+- name: Multus | Copy manifest files
+  copy:
+    src: "{{ item.file }}"
+    dest: "{{ kube_config_dir }}"
+  with_items:
+    - {name: multus-crd, file: multus-crd.yml, type: customresourcedefinition}
+    - {name: multus-serviceaccount, file: multus-serviceaccount.yml, type: serviceaccount}
+    - {name: multus-clusterrole, file: multus-clusterrole.yml, type: clusterrole}
+    - {name: multus-clusterrolebinding, file: multus-clusterrolebinding.yml, type: clusterrolebinding}
+  register: multus_manifest_1
+
+- name: Multus | Copy manifest templates
+  template:
+    src: "{{ item.file }}.j2"
+    dest: "{{ kube_config_dir }}/{{ item.file }}"
+  with_items:
+    - {name: multus-daemonset, file: multus-daemonset.yml, type: daemonset}
+  register: multus_manifest_2

roles/network_plugin/multus/templates/multus-daemonset.yml.j2

@@ -0,0 +1,54 @@
+---
+kind: DaemonSet
+apiVersion: extensions/v1beta1
+metadata:
+  name: kube-multus-ds-amd64
+  namespace: kube-system
+  labels:
+    tier: node
+    app: multus
+spec:
+  template:
+    metadata:
+      labels:
+        tier: node
+        app: multus
+    spec:
+      hostNetwork: true
+      nodeSelector:
+        beta.kubernetes.io/arch: amd64
+      tolerations:
+      - key: node-role.kubernetes.io/master
+        operator: Exists
+        effect: NoSchedule
+      serviceAccountName: multus
+      containers:
+      - name: kube-multus
+        image: {{ multus_image_repo }}:{{ multus_image_tag }}
+        command: ["/entrypoint.sh"]
+        args:
+        - "--cni-conf-dir={{ multus_cni_conf_dir }}"
+        - "--cni-bin-dir={{ multus_cni_bin_dir }}"
+        - "--multus-conf-file={{ multus_conf_file }}"
+        - "--multus-kubeconfig-file-host={{ multus_kubeconfig_file_host }}"
+        resources:
+          requests:
+            cpu: "100m"
+            memory: "50Mi"
+          limits:
+            cpu: "100m"
+            memory: "50Mi"
+        securityContext:
+          privileged: true
+        volumeMounts:
+        - name: cni
+          mountPath: {{  multus_cni_conf_dir }}
+        - name: cnibin
+          mountPath: {{ multus_cni_bin_dir }}
+      volumes:
+      - name: cni
+        hostPath:
+          path: {{ multus_cni_conf_dir_host }}
+      - name: cnibin
+        hostPath:
+          path: {{ multus_cni_bin_dir_host }}