Network: support down NIC

cmd/attack/network.go

@@ -49,6 +49,7 @@ func NewNetworkAttackCommand(uid *string) *cobra.Command {
 		NetworkDNSCommand(dep, options),
 		NewNetworkPortOccupiedCommand(dep, options),
 		NewNetworkBandwidthCommand(dep, options),
+		NewNICDownCommand(dep, options),
 	)
 
 	return cmd
@@ -268,3 +269,20 @@ func NewNetworkPortOccupiedCommand(dep fx.Option, options *core.NetworkCommand)
 	cmd.Flags().StringVarP(&options.Port, "port", "p", "", "this specified port is to occupied")
 	return cmd
 }
+
+func NewNICDownCommand(dep fx.Option, options *core.NetworkCommand) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "down",
+		Short: "down network interface card",
+
+		Run: func(cmd *cobra.Command, args []string) {
+			options.Action = core.NetworkNICDownAction
+			options.CompleteDefaults()
+			utils.FxNewAppWithoutLog(dep, fx.Invoke(commonNetworkAttackFunc)).Run()
+		},
+	}
+
+	cmd.Flags().StringVarP(&options.Device, "device", "d", "", "the network interface to impact")
+	SetScheduleFlags(cmd, &options.SchedulerConfig)
+	return cmd
+}

pkg/core/network.go

@@ -70,6 +70,7 @@ const (
 	NetworkPartitionAction    = "partition"
 	NetworkBandwidthAction    = "bandwidth"
 	NetworkPortOccupiedAction = "occupied"
+	NetworkNICDownAction      = "down"
 )
 
 func (n *NetworkCommand) Validate() error {
@@ -89,6 +90,8 @@ func (n *NetworkCommand) Validate() error {
 		return n.validNetworkOccupied()
 	case NetworkBandwidthAction:
 		return n.validNetworkBandwidth()
+	case NetworkNICDownAction:
+		return n.validNetworkNICDown()
 	default:
 		return errors.Errorf("network action %s not supported", n.Action)
 	}
@@ -203,6 +206,18 @@ func (n *NetworkCommand) validNetworkOccupied() error {
 	return nil
 }
 
+func (n *NetworkCommand) validNetworkNICDown() error {
+	if len(n.Duration) == 0 {
+		return errors.New("duration is required")
+	}
+
+	if len(n.Device) == 0 {
+		return errors.New("device is required")
+	}
+
+	return nil
+}
+
 func (n *NetworkCommand) CompleteDefaults() {
 	switch n.Action {
 	case NetworkDelayAction:

pkg/server/chaosd/network.go

@@ -85,6 +85,24 @@ func (networkAttack) Attack(options core.AttackConfig, env Environment) (err err
 				return errors.WithStack(err)
 			}
 		}
+
+	case core.NetworkNICDownAction:
+		if err := env.Chaos.getNICIP(attack); err != nil {
+			return errors.WithStack(err)
+		}
+
+		NICDownCommand := fmt.Sprintf("ifconfig %s down", attack.Device)
+
+		cmd := exec.Command("bash", "-c", NICDownCommand)
+		_, err := cmd.CombinedOutput()
+		if err != nil {
+			return errors.WithStack(err)
+		}
+
+		if attack.Duration != "-1" {
+			err := env.Chaos.recoverNICDownScheduled(attack)
+			return errors.WithStack(err)
+		}
 	}
 
 	return nil
@@ -348,6 +366,8 @@ func (networkAttack) Recover(exp core.Experiment, env Environment) error {
 				return errors.WithStack(err)
 			}
 		}
+	case core.NetworkNICDownAction:
+		return env.Chaos.recoverNICDown(attack)
 	}
 	return nil
 }
@@ -511,3 +531,54 @@ func (s *Server) recoverEtcHosts(attack *core.NetworkCommand, uid string) error
 	}
 	return nil
 }
+
+func (s *Server) recoverNICDown(attack *core.NetworkCommand) error {
+	NICUpCommand := fmt.Sprintf("ifconfig %s %s up", attack.Device, attack.IPAddress)
+
+	recoverCmd := exec.Command("bash", "-c", NICUpCommand)
+	_, err := recoverCmd.CombinedOutput()
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (s *Server) recoverNICDownScheduled(attack *core.NetworkCommand) error {
+	NICUpCommand := fmt.Sprintf("sleep %s && ifconfig %s %s up", attack.Duration, attack.Device, attack.IPAddress)
+
+	recoverCmd := exec.Command("bash", "-c", NICUpCommand)
+	_, err := recoverCmd.CombinedOutput()
+	if err != nil {
+		return errors.WithStack(err)
+	}
+	return nil
+}
+
+// getNICIP() uses `ifconfig` to get interfaces' IP. The reason for
+// not using net.Interfaces() is that net.Interfaces() can't get
+// sub interfaces.
+func (s *Server) getNICIP(attack *core.NetworkCommand) error {
+	getIPCommand := fmt.Sprintf("ifconfig %s | awk '/inet\\>/ {print $2}'", attack.Device)
+
+	cmd := exec.Command("bash", "-c", getIPCommand)
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err = cmd.Start(); err != nil {
+		return errors.WithStack(err)
+	}
+
+	stdoutBytes := make([]byte, 1024)
+	_, err = stdout.Read(stdoutBytes)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+	// When stdoutBytes is converted to string, the string will be IPAddress with a few unnecessary
+	// zeros, which makes IPAddress' format wrong, so the trailing zeros needs to be trimmed.
+	attack.IPAddress = strings.TrimRight(string(stdoutBytes), "\n\x00")
+
+	return nil
+}

test/integration_test/network/run.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+
+# Copyright 2022 Chaos Mesh Authors.
+#
+# 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,
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -u
+
+cur=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
+cd $cur
+
+bin_path=../../../bin
+
+# test nic down
+nic=$(cat /proc/net/dev | awk '{i++; if(i>2){print $1}}' | sed 's/^[\t]*//g' | sed 's/[:]*$//g' | head -n 1)
+
+ifconfig ${nic}:0 192.168.10.28 up
+
+test_nic=$(ifconfig | grep ${nic}:0 | sed 's/:0:.*/:0/g')
+if [[ test_nic == "" ]]; then
+    echo "create test nic failed"
+    exit 1
+fi
+
+${bin_path}/chaosd attack network down -d ${test_nic} --duration 1s
+stat=$(ifconfig | grep ${test_nic} | sed 's/:0:.*/:0/g')
+
+if [[ -n ${stat} ]]; then
+    echo "fail to disable the test nic"
+    ifconfig ${test_nic} down
+    exit 1
+fi
+
+sleep 1s
+
+stat=$(ifconfig | grep ${test_nic} | sed 's/:0:.*/:0/g')
+if [[ ${stat} != ${test_nic} ]]; then
+    echo "fail to enable the test nic"
+    exit 1
+fi
+
+ifconfig ${test_nic} down
+
+exit 0