support specifying routes when providing IPAM for other CNI plugins

[zhangzujian]

Pull Request

• Make sure you have followed Kube-OVN Code Style.

What type of this PR

• Feature

With this patch, routes can be specified via network attachment definition:

apiVersion: k8s.cni.cncf.io/v1
kind: NetworkAttachmentDefinition
metadata:
  name: macvlan
  namespace: default
spec:
  config: |
    {
      "cniVersion": "0.3.1",
      "type": "macvlan",
      "master": "eth0",
      "mode": "bridge",
      "ipam": {
        "type": "kube-ovn",
        "server_socket": "/run/openvswitch/kube-ovn-daemon.sock",
        "provider": "macvlan.default",
        "routes": [
          {
            "dst": "192.168.0.0/16",
            "gw": "99.99.1.1"
          },
          {
            "gw": "99.99.1.254"
          }
        ]
      }
    }

Or via pod annotations:

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: macvlan
  namespace: default
spec:
  selector:
    matchLabels:
      app: macvlan
  template:
    metadata:
      labels:
        app: macvlan
      annotations:
        k8s.v1.cni.cncf.io/networks: default/macvlan
        macvlan.default.kubernetes.io/routes: |
          [{
            "dst": "192.169.1.0/24",
            "gw": "99.99.1.99"
          }]
    spec:
      containers:
      - name: pod
        image: kubeovn/kube-ovn:v1.13.0
        command:
        - sh
        - -c
        - sleep 10000

Result:

root@macvlan-n4flx:/# ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: net1@if62: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default
    link/ether 82:ac:4d:0b:b5:da brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 99.99.1.6/24 brd 99.99.1.255 scope global net1
       valid_lft forever preferred_lft forever
    inet6 fe80::80ac:4dff:fe0b:b5da/64 scope link
       valid_lft forever preferred_lft forever
53: eth0@if54: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1400 qdisc noqueue state UP group default
    link/ether 00:00:00:d6:17:c2 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 10.16.0.20/16 brd 10.16.255.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fd00:10:16::14/112 scope global
       valid_lft forever preferred_lft forever
    inet6 fe80::200:ff:fed6:17c2/64 scope link
       valid_lft forever preferred_lft forever
root@macvlan-n4flx:/# ip route show
default via 99.99.1.254 dev net1
10.16.0.0/16 dev eth0 proto kernel scope link src 10.16.0.20
99.99.1.0/24 dev net1 proto kernel scope link src 99.99.1.6
192.168.0.0/24 via 99.99.1.1 dev net1
192.169.1.0/24 via 99.99.1.99 dev net1