11.2.3. 为集群配置网络策略审计

验证

1. 要创建带有网络策略的命名空间，请完成以下步骤：

   1. 创建命名空间进行验证：

      $ cat <<EOF| oc create -f -
      kind: Namespace
      apiVersion: v1
      metadata:
        name: verify-audit-logging
        annotations:
          k8s.ovn.org/acl-logging: '{ "deny": "alert", "allow": "alert" }'
      EOF

      输出示例

      namespace/verify-audit-logging created

   2. 启用审计日志记录：

      $ oc annotate namespace verify-audit-logging k8s.ovn.org/acl-logging='{ "deny": "alert", "allow": "alert" }'

      namespace/verify-audit-logging annotated

   3. 为命名空间创建网络策略：

      $ cat <<EOF| oc create -n verify-audit-logging -f -
      apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: deny-all
      spec:
        podSelector:
          matchLabels:
        policyTypes:
        - Ingress
        - Egress
      ---
      apiVersion: networking.k8s.io/v1
      kind: NetworkPolicy
      metadata:
        name: allow-from-same-namespace
      spec:
        podSelector: {}
        policyTypes:
         - Ingress
         - Egress
        ingress:
          - from:
              - podSelector: {}
        egress:
          - to:
             - namespaceSelector:
                matchLabels:
                  namespace: verify-audit-logging
      EOF

      输出示例

      networkpolicy.networking.k8s.io/deny-all created
      networkpolicy.networking.k8s.io/allow-from-same-namespace created

2. 为 default 命名空间中的源流量创建 pod：

   $ cat <<EOF| oc create -n default -f -
   apiVersion: v1
   kind: Pod
   metadata:
     name: client
   spec:
     containers:
       - name: client
         image: registry.access.redhat.com/rhel7/rhel-tools
         command: ["/bin/sh", "-c"]
         args:
           ["sleep inf"]
   EOF

3. 在 verify-audit-logging 命名空间中创建两个 pod：

   $ for name in client server; do
   cat <<EOF| oc create -n verify-audit-logging -f -
   apiVersion: v1
   kind: Pod
   metadata:
     name: ${name}
   spec:
     containers:
       - name: ${name}
         image: registry.access.redhat.com/rhel7/rhel-tools
         command: ["/bin/sh", "-c"]
         args:
           ["sleep inf"]
   EOF
   done

   输出示例

   pod/client created
   pod/server created

4. 要生成流量并生成网络策略审计日志条目，请完成以下步骤：

   1. 在 verify-audit-logging 命名空间中获取名为 server 的 pod 的 IP 地址：

      $ POD_IP=$(oc get pods server -n verify-audit-logging -o jsonpath='{.status.podIP}')

   2. 从 default 命名空间中名为 client 的 pod 中 ping 上一个命令的 IP 地址，并确认所有数据包都已丢弃：

      $ oc exec -it client -n default -- /bin/ping -c 2 $POD_IP

      输出示例

      PING 10.128.2.55 (10.128.2.55) 56(84) bytes of data.
      
      --- 10.128.2.55 ping statistics ---
      2 packets transmitted, 0 received, 100% packet loss, time 2041ms

   3. 从 verify-audit-logging 命名空间中名为 client 的 pod 中 ping POD_IP shell 环境变量中保存的 IP 地址，并确认允许所有数据包：

      $ oc exec -it client -n verify-audit-logging -- /bin/ping -c 2 $POD_IP

      输出示例

      PING 10.128.0.86 (10.128.0.86) 56(84) bytes of data.
      64 bytes from 10.128.0.86: icmp_seq=1 ttl=64 time=2.21 ms
      64 bytes from 10.128.0.86: icmp_seq=2 ttl=64 time=0.440 ms
      
      --- 10.128.0.86 ping statistics ---
      2 packets transmitted, 2 received, 0% packet loss, time 1001ms
      rtt min/avg/max/mdev = 0.440/1.329/2.219/0.890 ms

5. 显示网络策略审计日志中的最新条目：

   $ for pod in $(oc get pods -n openshift-ovn-kubernetes -l app=ovnkube-node --no-headers=true | awk '{ print $1 }') ; do
       oc exec -it $pod -n openshift-ovn-kubernetes -- tail -4 /var/log/ovn/acl-audit-log.log
     done

   输出示例

   Defaulting container name to ovn-controller.
   Use 'oc describe pod/ovnkube-node-hdb8v -n openshift-ovn-kubernetes' to see all of the containers in this pod.
   2021-06-13T19:33:11.590Z|00005|acl_log(ovn_pinctrl0)|INFO|name="verify-audit-logging_deny-all", verdict=drop, severity=alert: icmp,vlan_tci=0x0000,dl_src=0a:58:0a:80:02:39,dl_dst=0a:58:0a:80:02:37,nw_src=10.128.2.57,nw_dst=10.128.2.55,nw_tos=0,nw_ecn=0,nw_ttl=64,icmp_type=8,icmp_code=0
   2021-06-13T19:33:12.614Z|00006|acl_log(ovn_pinctrl0)|INFO|name="verify-audit-logging_deny-all", verdict=drop, severity=alert: icmp,vlan_tci=0x0000,dl_src=0a:58:0a:80:02:39,dl_dst=0a:58:0a:80:02:37,nw_src=10.128.2.57,nw_dst=10.128.2.55,nw_tos=0,nw_ecn=0,nw_ttl=64,icmp_type=8,icmp_code=0
   2021-06-13T19:44:10.037Z|00007|acl_log(ovn_pinctrl0)|INFO|name="verify-audit-logging_allow-from-same-namespace_0", verdict=allow, severity=alert: icmp,vlan_tci=0x0000,dl_src=0a:58:0a:80:02:3b,dl_dst=0a:58:0a:80:02:3a,nw_src=10.128.2.59,nw_dst=10.128.2.58,nw_tos=0,nw_ecn=0,nw_ttl=64,icmp_type=8,icmp_code=0
   2021-06-13T19:44:11.037Z|00008|acl_log(ovn_pinctrl0)|INFO|name="verify-audit-logging_allow-from-same-namespace_0", verdict=allow, severity=alert: icmp,vlan_tci=0x0000,dl_src=0a:58:0a:80:02:3b,dl_dst=0a:58:0a:80:02:3a,nw_src=10.128.2.59,nw_dst=10.128.2.58,nw_tos=0,nw_ecn=0,nw_ttl=64,icmp_type=8,icmp_code=0