integration: simplify CNI-fp and add README.md
* Use delegated plugin call to simplify cni-bridge-cni * Add README.md for cni-bridge-cni Signed-off-by: Wei Fu <fuweid89@gmail.com>
This commit is contained in:
Wei Fu
159
integration/failpoint/cmd/cni-bridge-fp/README.md
Normal file
159
integration/failpoint/cmd/cni-bridge-fp/README.md
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@@ -0,0 +1,159 @@
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## cni-bridge-f(ail)p(oint)
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### Overview
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The `cni-bridge-fp` is a CNI plugin which delegates interface-creating function
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to [CNI bridge plugin][1] and allows user to inject failpoint before delegation.
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Since the CNI plugin is invoked by binary call from CRI and it is short-lived,
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the failpoint need to be configured by a JSON file, which can be persisted.
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There is an example about failpoint description.
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```json
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{
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"cmdAdd": "1*error(you-shall-not-pass!)->1*panic(again)",
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"cmdDel": "1*error(try-again)",
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"cmdCheck": "10*off"
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}
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```
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* `cmdAdd` (string, optional): The failpoint for `ADD` command.
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* `cmdDel` (string, optional): The failpoint for `DEL` command.
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* `cmdCheck` (string, optional): The failpoint for `CHECK` command.
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Since the `cmdXXX` can be multiple failpoints, each CNI binary call will update
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the current state to make sure the order of execution is expected.
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And the failpoint injection is enabled by pod's annotation. Currently, the key
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of customized CNI capabilities in containerd can only be `io.kubernetes.cri.pod-annotations`
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and containerd will pass pod's annotations to CNI under the that object. The
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user can use the `failpoint.cni.containerd.io/confpath` annotation to enable
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failpoint for the pod.
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```yaml
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apiVersion: v1
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kind: Pod
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metadata:
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name: nginx
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annotations:
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failpoint.cni.containerd.io/confpath: "/tmp/pod-failpoints.json"
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spec:
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containers:
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- name: nginx
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image: nginx:1.14.2
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ports:
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- containerPort: 80
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```
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### Example
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Let's use the following json as failpoint description.
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```bash
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$ cat <<EOF | tee /tmp/cni-failpoint.json
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{
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"cmdAdd": "1*error(try-again)",
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"cmdDel": "2*error(oops)",
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"cmdCheck": "1*off->1*panic(sorry)"
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}
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EOF
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```
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And use `ip netns` to create persisted net namespace named by `failpoint`.
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```bash
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$ sudo ip netns add failpoint
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```
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And then setup the following bash script for demo.
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```bash
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$ cat <<EOFDEMO | tee /tmp/cni-failpoint-demo-helper.sh
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#!/usr/bin/env bash
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export CNI_CONTAINERID=failpoint-testing
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export CNI_NETNS=/run/netns/failpoint
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export CNI_IFNAME=fpeni0
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export CNI_PATH=/opt/cni/bin/
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cat <<EOF | /opt/cni/bin/cni-bridge-fp
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{
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"cniVersion": "0.3.0",
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"name": "containerd-net-fp",
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"type": "cni-bridge-fp",
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"bridge": "fp-cni0",
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"isGateway": true,
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"ipMasq": true,
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"promiscMode": true,
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"ipam": {
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"type": "host-local",
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"ranges": [
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[{
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"subnet": "10.88.0.0/16"
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}],
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[{
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"subnet": "2001:4860:4860::/64"
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}]
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],
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"routes": [
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{ "dst": "0.0.0.0/0" },
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{ "dst": "::/0" }
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]
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},
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"runtimeConfig": {
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"io.kubernetes.cri.pod-annotations": {
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"failpoint.cni.containerd.io/confpath": "/tmp/cni-failpoint.json"
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}
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}
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}
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EOF
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EOFDEMO
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```
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Let's try to setup CNI and we should get a error `try-again`.
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```bash
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$ sudo CNI_COMMAND=ADD bash /tmp/cni-failpoint-demo-helper.sh
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{
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"code": 999,
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"msg": "try-again"
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}
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# there is no failpoint for ADD command.
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$ cat /tmp/cni-failpoint.json | jq .
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{
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"cmdAdd": "0*error(try-again)",
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"cmdDel": "2*error(oops)",
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"cmdCheck": "1*off->1*panic(sorry)"
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}
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```
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We should setup CNI successfully after retry. When we teardown the interface,
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there should be two failpoints.
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```bash
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$ sudo CNI_COMMAND=ADD bash /tmp/cni-failpoint-demo-helper.sh
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...
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$ sudo CNI_COMMAND=DEL bash /tmp/cni-failpoint-demo-helper.sh
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{
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"code": 999,
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"msg": "oops"
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}
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$ sudo CNI_COMMAND=DEL bash /tmp/cni-failpoint-demo-helper.sh
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{
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"code": 999,
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"msg": "oops"
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}
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$ cat /tmp/cni-failpoint.json | jq .
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{
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"cmdAdd": "0*error(try-again)",
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"cmdDel": "0*error(oops)",
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"cmdCheck": "1*off->1*panic(sorry)"
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}
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```
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[1]: <https://www.cni.dev/plugins/current/main/bridge/>
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@@ -1,209 +0,0 @@
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//go:build linux
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// +build linux
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/*
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Copyright The containerd Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package main
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import (
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"bytes"
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"encoding/json"
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"fmt"
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"io/ioutil"
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"os"
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"os/exec"
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"path/filepath"
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"strings"
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"syscall"
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"github.com/containerd/containerd/pkg/failpoint"
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"github.com/containerd/continuity"
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"github.com/sirupsen/logrus"
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)
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type inheritedPodAnnotations struct {
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// CNIFailpointControlStateDir is used to specify the location of
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// failpoint control setting. In that such stateDir, the failpoint
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// setting is stored in the json file named by
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// `${K8S_POD_NAMESPACE}-${K8S_POD_NAME}.json`. The detail of json file
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// is described by FailpointConf.
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CNIFailpointControlStateDir string `json:"cniFailpointControlStateDir,omitempty"`
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}
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// FailpointConf is used to describe cmdAdd/cmdDel/cmdCheck command's failpoint.
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type FailpointConf struct {
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Add string `json:"cmdAdd"`
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Del string `json:"cmdDel"`
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Check string `json:"cmdCheck"`
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}
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type netConf struct {
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RuntimeConfig struct {
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PodAnnotations inheritedPodAnnotations `json:"io.kubernetes.cri.pod-annotations"`
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} `json:"runtimeConfig,omitempty"`
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}
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func main() {
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stdinData, err := ioutil.ReadAll(os.Stdin)
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if err != nil {
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logrus.Fatalf("failed to read stdin: %v", err)
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}
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var conf netConf
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if err := json.Unmarshal(stdinData, &conf); err != nil {
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logrus.Fatalf("failed to parse network configuration: %v", err)
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}
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cniCmd, ok := os.LookupEnv("CNI_COMMAND")
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if !ok {
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logrus.Fatal("required env CNI_COMMAND")
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}
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cniPath, ok := os.LookupEnv("CNI_PATH")
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if !ok {
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logrus.Fatal("required env CNI_PATH")
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}
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evalFn, err := buildFailpointEval(conf.RuntimeConfig.PodAnnotations.CNIFailpointControlStateDir, cniCmd)
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if err != nil {
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logrus.Fatalf("failed to build failpoint evaluate function: %v", err)
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}
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if err := evalFn(); err != nil {
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logrus.Fatalf("failpoint: %v", err)
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}
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cmd := exec.Command(filepath.Join(cniPath, "bridge"))
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cmd.Stdin = bytes.NewReader(stdinData)
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cmd.Stdout = os.Stdout
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cmd.Stderr = os.Stderr
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if err := cmd.Start(); err != nil {
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logrus.Fatalf("failed to start bridge cni plugin: %v", err)
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}
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if err := cmd.Wait(); err != nil {
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logrus.Fatalf("failed to wait for bridge cni plugin: %v", err)
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}
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}
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// buildFailpointEval will read and update the failpoint setting and then
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// return delegated failpoint evaluate function
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func buildFailpointEval(stateDir string, cniCmd string) (failpoint.EvalFn, error) {
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cniArgs, ok := os.LookupEnv("CNI_ARGS")
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if !ok {
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return nopEvalFn, nil
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}
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target := buildPodFailpointFilepath(stateDir, cniArgs)
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if target == "" {
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return nopEvalFn, nil
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}
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f, err := os.OpenFile(target, os.O_RDWR, 0666)
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if err != nil {
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if os.IsNotExist(err) {
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return nopEvalFn, nil
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}
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return nil, fmt.Errorf("failed to open file %s: %w", target, err)
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}
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defer f.Close()
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if err := syscall.Flock(int(f.Fd()), syscall.LOCK_EX); err != nil {
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return nil, fmt.Errorf("failed to lock failpoint setting %s: %w", target, err)
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}
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defer syscall.Flock(int(f.Fd()), syscall.LOCK_UN)
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data, err := ioutil.ReadAll(f)
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if err != nil {
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return nil, fmt.Errorf("failed to read failpoint setting %s: %w", target, err)
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}
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var conf FailpointConf
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if err := json.Unmarshal(data, &conf); err != nil {
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return nil, fmt.Errorf("failed to unmarshal failpoint conf %s: %w", string(data), err)
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}
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var fpStr *string
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switch cniCmd {
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case "ADD":
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fpStr = &conf.Add
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case "DEL":
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fpStr = &conf.Del
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case "CHECK":
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fpStr = &conf.Check
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}
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if fpStr == nil || *fpStr == "" {
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return nopEvalFn, nil
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}
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fp, err := failpoint.NewFailpoint(cniCmd, *fpStr)
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if err != nil {
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return nil, fmt.Errorf("failed to parse failpoint %s: %w", *fpStr, err)
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}
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evalFn := fp.DelegatedEval()
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*fpStr = fp.Marshal()
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data, err = json.Marshal(conf)
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if err != nil {
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return nil, fmt.Errorf("failed to marshal failpoint conf: %w", err)
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}
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return evalFn, continuity.AtomicWriteFile(target, data, 0666)
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}
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// buildPodFailpointFilepath returns the expected failpoint setting filepath
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// by Pod metadata.
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func buildPodFailpointFilepath(stateDir, cniArgs string) string {
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args := cniArgsIntoKeyValue(cniArgs)
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res := make([]string, 0, 2)
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for _, key := range []string{"K8S_POD_NAMESPACE", "K8S_POD_NAME"} {
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v, ok := args[key]
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if !ok {
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break
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}
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res = append(res, v)
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}
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if len(res) != 2 {
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return ""
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}
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return filepath.Join(stateDir, strings.Join(res, "-")+".json")
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}
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// cniArgsIntoKeyValue converts the CNI ARGS from `key1=value1;key2=value2...`
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// into key/value hashmap.
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func cniArgsIntoKeyValue(envStr string) map[string]string {
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parts := strings.Split(envStr, ";")
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res := make(map[string]string, len(parts))
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for _, part := range parts {
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keyValue := strings.SplitN(part, "=", 2)
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if len(keyValue) != 2 {
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continue
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}
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res[keyValue[0]] = keyValue[1]
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}
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return res
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}
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func nopEvalFn() error {
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return nil
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}
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202
integration/failpoint/cmd/cni-bridge-fp/main_linux.go
Normal file
202
integration/failpoint/cmd/cni-bridge-fp/main_linux.go
Normal file
@@ -0,0 +1,202 @@
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/*
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Copyright The containerd Authors.
|
||||
|
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Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package main
|
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|
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import (
|
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"context"
|
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"encoding/json"
|
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"fmt"
|
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"io/ioutil"
|
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"os"
|
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"path/filepath"
|
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"syscall"
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|
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"github.com/containerd/containerd/pkg/failpoint"
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"github.com/containerd/continuity"
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"github.com/containernetworking/cni/pkg/invoke"
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"github.com/containernetworking/cni/pkg/skel"
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"github.com/containernetworking/cni/pkg/version"
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)
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const delegatedPlugin = "bridge"
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type netConf struct {
|
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RuntimeConfig struct {
|
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PodAnnotations inheritedPodAnnotations `json:"io.kubernetes.cri.pod-annotations"`
|
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} `json:"runtimeConfig,omitempty"`
|
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}
|
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|
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type inheritedPodAnnotations struct {
|
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// FailpointConfPath represents filepath of failpoint settings.
|
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FailpointConfPath string `json:"failpoint.cni.containerd.io/confpath,omitempty"`
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}
|
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|
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// failpointConf is used to describe cmdAdd/cmdDel/cmdCheck command's failpoint.
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type failpointConf struct {
|
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Add string `json:"cmdAdd,omitempty"`
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Del string `json:"cmdDel,omitempty"`
|
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Check string `json:"cmdCheck,omitempty"`
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}
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func main() {
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skel.PluginMain(cmdAdd, cmdCheck, cmdDel, version.All, "bridge with failpoint support")
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}
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|
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func cmdAdd(args *skel.CmdArgs) error {
|
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if err := handleFailpoint(args, "ADD"); err != nil {
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return err
|
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}
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|
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result, err := invoke.DelegateAdd(context.TODO(), delegatedPlugin, args.StdinData, nil)
|
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if err != nil {
|
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return err
|
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}
|
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return result.Print()
|
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}
|
||||
|
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func cmdCheck(args *skel.CmdArgs) error {
|
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if err := handleFailpoint(args, "CHECK"); err != nil {
|
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return err
|
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}
|
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|
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return invoke.DelegateCheck(context.TODO(), delegatedPlugin, args.StdinData, nil)
|
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}
|
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|
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func cmdDel(args *skel.CmdArgs) error {
|
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if err := handleFailpoint(args, "DEL"); err != nil {
|
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return err
|
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}
|
||||
|
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return invoke.DelegateDel(context.TODO(), delegatedPlugin, args.StdinData, nil)
|
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}
|
||||
|
||||
func handleFailpoint(args *skel.CmdArgs, cmdKind string) error {
|
||||
var conf netConf
|
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if err := json.Unmarshal(args.StdinData, &conf); err != nil {
|
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return fmt.Errorf("failed to parse network configuration: %w", err)
|
||||
}
|
||||
|
||||
confPath := conf.RuntimeConfig.PodAnnotations.FailpointConfPath
|
||||
if len(confPath) == 0 {
|
||||
return nil
|
||||
}
|
||||
|
||||
control, err := newFailpointControl(confPath)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
evalFn, err := control.delegatedEvalFn(cmdKind)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
return evalFn()
|
||||
}
|
||||
|
||||
type failpointControl struct {
|
||||
confPath string
|
||||
}
|
||||
|
||||
func newFailpointControl(confPath string) (*failpointControl, error) {
|
||||
if !filepath.IsAbs(confPath) {
|
||||
return nil, fmt.Errorf("failpoint confPath(%s) is required to be absolute", confPath)
|
||||
}
|
||||
|
||||
return &failpointControl{
|
||||
confPath: confPath,
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (c *failpointControl) delegatedEvalFn(cmdKind string) (failpoint.EvalFn, error) {
|
||||
var resFn failpoint.EvalFn = nopEvalFn
|
||||
|
||||
if err := c.updateTx(func(conf *failpointConf) error {
|
||||
var fpStr *string
|
||||
|
||||
switch cmdKind {
|
||||
case "ADD":
|
||||
fpStr = &conf.Add
|
||||
case "DEL":
|
||||
fpStr = &conf.Del
|
||||
case "CHECK":
|
||||
fpStr = &conf.Check
|
||||
}
|
||||
|
||||
if fpStr == nil || *fpStr == "" {
|
||||
return nil
|
||||
}
|
||||
|
||||
fp, err := failpoint.NewFailpoint(cmdKind, *fpStr)
|
||||
if err != nil {
|
||||
return fmt.Errorf("failed to parse failpoint %s: %w", *fpStr, err)
|
||||
}
|
||||
|
||||
resFn = fp.DelegatedEval()
|
||||
|
||||
*fpStr = fp.Marshal()
|
||||
return nil
|
||||
|
||||
}); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return resFn, nil
|
||||
}
|
||||
|
||||
func (c *failpointControl) updateTx(updateFn func(conf *failpointConf) error) error {
|
||||
f, err := os.OpenFile(c.confPath, os.O_RDWR, 0666)
|
||||
if err != nil {
|
||||
return fmt.Errorf("failed to open confPath %s: %w", c.confPath, err)
|
||||
}
|
||||
defer f.Close()
|
||||
|
||||
if err := flock(f.Fd()); err != nil {
|
||||
return fmt.Errorf("failed to lock failpoint setting %s: %w", c.confPath, err)
|
||||
}
|
||||
defer unflock(f.Fd())
|
||||
|
||||
data, err := ioutil.ReadAll(f)
|
||||
if err != nil {
|
||||
return fmt.Errorf("failed to read failpoint setting %s: %w", c.confPath, err)
|
||||
}
|
||||
|
||||
var conf failpointConf
|
||||
if err := json.Unmarshal(data, &conf); err != nil {
|
||||
return fmt.Errorf("failed to unmarshal failpoint conf %s: %w", string(data), err)
|
||||
}
|
||||
|
||||
if err := updateFn(&conf); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
data, err = json.Marshal(conf)
|
||||
if err != nil {
|
||||
return fmt.Errorf("failed to marshal failpoint conf: %w", err)
|
||||
}
|
||||
return continuity.AtomicWriteFile(c.confPath, data, 0666)
|
||||
}
|
||||
|
||||
func nopEvalFn() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func flock(fd uintptr) error {
|
||||
return syscall.Flock(int(fd), syscall.LOCK_EX)
|
||||
}
|
||||
|
||||
func unflock(fd uintptr) error {
|
||||
return syscall.Flock(int(fd), syscall.LOCK_UN)
|
||||
}
|
||||
@@ -1,6 +1,3 @@
|
||||
//go:build linux
|
||||
// +build linux
|
||||
|
||||
/*
|
||||
Copyright The containerd Authors.
|
||||
|
||||
@@ -1,6 +1,3 @@
|
||||
//go:build linux
|
||||
// +build linux
|
||||
|
||||
/*
|
||||
Copyright The containerd Authors.
|
||||
|
||||
@@ -39,7 +39,7 @@ const (
|
||||
|
||||
failpointShimPrefixKey = "io.containerd.runtime.v2.shim.failpoint."
|
||||
|
||||
failpointCNIStateDirKey = "cniFailpointControlStateDir"
|
||||
failpointCNIConfPathKey = "failpoint.cni.containerd.io/confpath"
|
||||
)
|
||||
|
||||
func TestRunPodSandboxWithSetupCNIFailure(t *testing.T) {
|
||||
@@ -109,7 +109,7 @@ func injectCNIFailpoint(t *testing.T, sbConfig *criapiv1.PodSandboxConfig, conf
|
||||
err = os.WriteFile(fpFilename, data, 0666)
|
||||
require.NoError(t, err)
|
||||
|
||||
sbConfig.Annotations[failpointCNIStateDirKey] = stateDir
|
||||
sbConfig.Annotations[failpointCNIConfPathKey] = fpFilename
|
||||
}
|
||||
|
||||
func injectShimFailpoint(t *testing.T, sbConfig *criapiv1.PodSandboxConfig, methodFps map[string]string) {
|
||||
|
||||
Reference in New Issue
Block a user