Andrey Smirnov 7767a41d4a feat: set interface MTU in DHCP mode even if DHCP is not successful
Fixes #2789

Signed-off-by: Andrey Smirnov <smirnov.andrey@gmail.com>
2020-11-19 10:59:21 -08:00

351 lines
8.9 KiB
Go

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
package qemu
import (
"context"
"fmt"
"log"
"net"
"os"
"os/exec"
"strconv"
"strings"
"github.com/containernetworking/cni/libcni"
"github.com/containernetworking/cni/pkg/types/current"
"github.com/containernetworking/plugins/pkg/ns"
"github.com/containernetworking/plugins/pkg/testutils"
"github.com/google/uuid"
"github.com/talos-systems/go-blockdevice/blockdevice/table/gpt"
"github.com/talos-systems/talos/pkg/provision"
"github.com/talos-systems/talos/pkg/provision/internal/cniutils"
"github.com/talos-systems/talos/pkg/provision/providers/vm"
)
// LaunchConfig is passed in to the Launch function over stdin.
type LaunchConfig struct {
StatePath string
// VM options
DiskPaths []string
VCPUCount int64
MemSize int64
QemuExecutable string
KernelImagePath string
InitrdPath string
PFlashImages []string
KernelArgs string
MachineType string
EnableKVM bool
BootloaderEnabled bool
NodeUUID uuid.UUID
// Talos config
Config string
// Network
NetworkConfig *libcni.NetworkConfigList
CNI provision.CNIConfig
IP net.IP
CIDR net.IPNet
Hostname string
GatewayAddr net.IP
MTU int
Nameservers []net.IP
// PXE
TFTPServer string
BootFilename string
IPXEBootFileName string
// API
APIPort int
// filled by CNI invocation
tapName string
vmMAC string
ns ns.NetNS
// signals
c chan os.Signal
// controller
controller *Controller
}
// withCNI creates network namespace, launches CNI and passes control to the next function
// filling config with netNS and interface details.
func withCNI(ctx context.Context, config *LaunchConfig, f func(config *LaunchConfig) error) error {
// random ID for the CNI, maps to single VM
containerID := uuid.New().String()
cniConfig := libcni.NewCNIConfigWithCacheDir(config.CNI.BinPath, config.CNI.CacheDir, nil)
// create a network namespace
ns, err := testutils.NewNS()
if err != nil {
return err
}
defer func() {
ns.Close() //nolint: errcheck
testutils.UnmountNS(ns) //nolint: errcheck
}()
ones, _ := config.CIDR.Mask.Size()
runtimeConf := libcni.RuntimeConf{
ContainerID: containerID,
NetNS: ns.Path(),
IfName: "veth0",
Args: [][2]string{
{"IP", fmt.Sprintf("%s/%d", config.IP, ones)},
{"GATEWAY", config.GatewayAddr.String()},
},
}
// attempt to clean up network in case it was deployed previously
err = cniConfig.DelNetworkList(ctx, config.NetworkConfig, &runtimeConf)
if err != nil {
return fmt.Errorf("error deleting CNI network: %w", err)
}
res, err := cniConfig.AddNetworkList(ctx, config.NetworkConfig, &runtimeConf)
if err != nil {
return fmt.Errorf("error provisioning CNI network: %w", err)
}
defer func() {
if e := cniConfig.DelNetworkList(ctx, config.NetworkConfig, &runtimeConf); e != nil {
log.Printf("error cleaning up CNI: %s", e)
}
}()
currentResult, err := current.NewResultFromResult(res)
if err != nil {
return fmt.Errorf("failed to parse cni result: %w", err)
}
vmIface, tapIface, err := cniutils.VMTapPair(currentResult, containerID)
if err != nil {
return fmt.Errorf(
"failed to parse VM network configuration from CNI output, ensure CNI is configured with a plugin " +
"that supports automatic VM network configuration such as tc-redirect-tap",
)
}
config.tapName = tapIface.Name
config.vmMAC = vmIface.Mac
config.ns = ns
// dump node IP/mac/hostname for dhcp
if err = vm.DumpIPAMRecord(config.StatePath, vm.IPAMRecord{
IP: config.IP,
Netmask: config.CIDR.Mask,
MAC: vmIface.Mac,
Hostname: config.Hostname,
Gateway: config.GatewayAddr,
MTU: config.MTU,
Nameservers: config.Nameservers,
TFTPServer: config.TFTPServer,
IPXEBootFilename: config.IPXEBootFileName,
}); err != nil {
return err
}
return f(config)
}
func checkPartitions(config *LaunchConfig) (bool, error) {
disk, err := os.Open(config.DiskPaths[0])
if err != nil {
return false, fmt.Errorf("failed to open disk file %w", err)
}
defer disk.Close() //nolint: errcheck
diskTable, err := gpt.NewGPT("vda", disk)
if err != nil {
return false, fmt.Errorf("error creating GPT object: %w", err)
}
if err = diskTable.Read(); err != nil {
return false, nil
}
return len(diskTable.Partitions()) > 0, nil
}
// launchVM runs qemu with args built based on config.
//
//nolint: gocyclo
func launchVM(config *LaunchConfig) error {
bootOrder := "cn"
if config.controller.ForcePXEBoot() {
bootOrder = "nc"
}
args := []string{
"-m", strconv.FormatInt(config.MemSize, 10),
"-smp", fmt.Sprintf("cpus=%d", config.VCPUCount),
"-cpu", "max",
"-nographic",
"-netdev", fmt.Sprintf("tap,id=net0,ifname=%s,script=no,downscript=no", config.tapName),
"-device", fmt.Sprintf("virtio-net-pci,netdev=net0,mac=%s", config.vmMAC),
// TODO: uncomment the following line to get another eth interface not connected to anything
// "-nic", "tap,model=virtio-net-pci",
"-device", "virtio-rng-pci",
"-no-reboot",
"-boot", fmt.Sprintf("order=%s,reboot-timeout=5000", bootOrder),
"-smbios", fmt.Sprintf("type=1,uuid=%s", config.NodeUUID),
}
for _, disk := range config.DiskPaths {
args = append(args, "-drive", fmt.Sprintf("format=raw,if=virtio,file=%s", disk))
}
machineArg := config.MachineType
if config.EnableKVM {
machineArg += ",accel=kvm"
}
args = append(args, "-machine", machineArg)
pflashArgs := make([]string, 2*len(config.PFlashImages))
for i := range config.PFlashImages {
pflashArgs[2*i] = "-drive"
pflashArgs[2*i+1] = fmt.Sprintf("file=%s,format=raw,if=pflash", config.PFlashImages[i])
}
args = append(args, pflashArgs...)
// check if disk is empty/wiped
diskBootable, err := checkPartitions(config)
if err != nil {
return err
}
if (!diskBootable || !config.BootloaderEnabled) && config.KernelImagePath != "" {
args = append(args,
"-kernel", config.KernelImagePath,
"-initrd", config.InitrdPath,
"-append", config.KernelArgs,
)
}
fmt.Fprintf(os.Stderr, "starting qemu with args:\n%s\n", strings.Join(args, " "))
cmd := exec.Command(
config.QemuExecutable,
args...,
)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := ns.WithNetNSPath(config.ns.Path(), func(_ ns.NetNS) error {
return cmd.Start()
}); err != nil {
return err
}
done := make(chan error)
go func() {
done <- cmd.Wait()
}()
for {
select {
case sig := <-config.c:
fmt.Fprintf(os.Stderr, "exiting VM as signal %s was received\n", sig)
if err := cmd.Process.Kill(); err != nil {
return fmt.Errorf("failed to kill process %w", err)
}
return fmt.Errorf("process stopped")
case err := <-done:
if err != nil {
return fmt.Errorf("process exited with error %s", err)
}
// graceful exit
return nil
case command := <-config.controller.CommandsCh():
if command == VMCommandStop {
fmt.Fprintf(os.Stderr, "exiting VM as stop command via API was received\n")
if err := cmd.Process.Kill(); err != nil {
return fmt.Errorf("failed to kill process %w", err)
}
<-done
return nil
}
}
}
}
// Launch a control process around qemu VM manager.
//
// This function is invoked from 'talosctl qemu-launch' hidden command
// and wraps starting, controlling 'qemu' VM process.
//
// Launch restarts VM forever until control process is stopped itself with a signal.
//
// Process is expected to receive configuration on stdin. Current working directory
// should be cluster state directory, process output should be redirected to the
// logfile in state directory.
//
// When signals SIGINT, SIGTERM are received, control process stops qemu and exits.
//
//nolint: gocyclo
func Launch() error {
var config LaunchConfig
ctx := context.Background()
if err := vm.ReadConfig(&config); err != nil {
return err
}
config.c = vm.ConfigureSignals()
config.controller = NewController()
httpServer, err := vm.NewHTTPServer(config.GatewayAddr, config.APIPort, []byte(config.Config), config.controller)
if err != nil {
return err
}
httpServer.Serve()
defer httpServer.Shutdown(ctx) //nolint: errcheck
// patch kernel args
config.KernelArgs = strings.ReplaceAll(config.KernelArgs, "{TALOS_CONFIG_URL}", fmt.Sprintf("http://%s/config.yaml", httpServer.GetAddr()))
return withCNI(ctx, &config, func(config *LaunchConfig) error {
for {
for config.controller.PowerState() != PoweredOn {
select {
case <-config.controller.CommandsCh():
// machine might have been powered on
case sig := <-config.c:
fmt.Fprintf(os.Stderr, "exiting stopped launcher as signal %s was received\n", sig)
return fmt.Errorf("process stopped")
}
}
if err := launchVM(config); err != nil {
return err
}
}
})
}