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Diffstat (limited to 'users/fcuny/exp/containerd-to-vm/cmd/c2vm/main.go')
-rw-r--r--users/fcuny/exp/containerd-to-vm/cmd/c2vm/main.go305
1 files changed, 0 insertions, 305 deletions
diff --git a/users/fcuny/exp/containerd-to-vm/cmd/c2vm/main.go b/users/fcuny/exp/containerd-to-vm/cmd/c2vm/main.go
deleted file mode 100644
index 320bc91..0000000
--- a/users/fcuny/exp/containerd-to-vm/cmd/c2vm/main.go
+++ /dev/null
@@ -1,305 +0,0 @@
-package main
-
-import (
-	"bufio"
-	"context"
-	"encoding/json"
-	"flag"
-	"fmt"
-	"io/ioutil"
-	"log"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"strings"
-
-	"github.com/containerd/containerd"
-	"github.com/containerd/containerd/content"
-	"github.com/containerd/containerd/images"
-	"github.com/containerd/containerd/namespaces"
-	"github.com/containerd/containerd/platforms"
-	"github.com/docker/docker/pkg/archive"
-	"github.com/firecracker-microvm/firecracker-go-sdk"
-	"github.com/firecracker-microvm/firecracker-go-sdk/client/models"
-	"github.com/google/renameio"
-	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
-)
-
-const (
-	containerdSock   = "/run/containerd/containerd.sock"
-	defaultNamespace = "c2vm"
-)
-
-var (
-	firecrackerSock = filepath.Join(os.Getenv("XDG_RUNTIME_DIR"), "firecracker.sock")
-	platform        = platforms.Only(ocispec.Platform{
-		OS:           "linux",
-		Architecture: "amd64",
-	})
-)
-
-func main() {
-	var (
-		containerName     = flag.String("container", "", "Name of the container")
-		outFile           = flag.String("out", "container.img", "Path to store the image")
-		kernel            = flag.String("kernel", "", "Path to the linux kernel image")
-		firecrackerBinary = flag.String("firecracker-binary", "", "Path to the firecracker binary")
-		metricsFifo       = flag.String("metrics-fifo", "", "FIFO to the firecracker metrics")
-	)
-
-	flag.Parse()
-
-	if *containerName == "" {
-		log.Fatal("a container is required")
-	}
-
-	if *kernel == "" {
-		log.Fatalf("a linux kernel is required")
-	}
-
-	if *firecrackerBinary == "" {
-		log.Fatalf("the path to the firecracker binary is required")
-	}
-
-	client, err := containerd.New(containerdSock)
-	if err != nil {
-		log.Fatalf("failed to create a client for containerd: %v", err)
-	}
-	defer client.Close()
-
-	ctx := namespaces.WithNamespace(context.Background(), defaultNamespace)
-	ctx, done, err := client.WithLease(ctx)
-	if err != nil {
-		log.Fatalf("failed to get a lease: %v", err)
-	}
-	defer done(ctx)
-
-	image, err := client.Pull(ctx, *containerName, containerd.WithPlatformMatcher(platform))
-	if err != nil {
-		log.Fatalf("failed to pull the container %s: %v\n", *containerName, err)
-	}
-
-	imageSize, err := image.Usage(ctx, containerd.WithUsageManifestLimit(1))
-	if err != nil {
-		log.Fatalf("failed to get the size of the image: %v", err)
-	}
-
-	log.Printf("pulled %s (%d bytes)\n", image.Name(), imageSize)
-
-	mntDir, err := ioutil.TempDir("", "c2vm")
-	if err != nil {
-		log.Fatalf("Failed to create mount temp dir: %v\n", err)
-	}
-
-	if err := createLoopDevice(*outFile, mntDir); err != nil {
-		log.Fatalf("%v\n", err)
-	}
-
-	if err := extract(ctx, client, image, mntDir); err != nil {
-		log.Fatalf("failed to extract the container: %v\n", err)
-	}
-
-	if err = initScript(ctx, client, image, mntDir); err != nil {
-		log.Fatalf("failed to create init script: %s\n", err)
-	}
-
-	if err = extraFiles(mntDir); err != nil {
-		log.Fatalf("failed to add extra files to the image: %v\n", err)
-	}
-
-	if err := detachLoopDevice(mntDir); err != nil {
-		log.Fatalf("failed to umount %s: %v\n", mntDir, err)
-	}
-
-	if err := resizeImage(*outFile); err != nil {
-		log.Fatalf("failed to resize the image %s: %s\n", *outFile, err)
-	}
-
-	bootVM(ctx, *outFile, *kernel, *firecrackerBinary, *metricsFifo)
-}
-
-func extract(ctx context.Context, client *containerd.Client, image containerd.Image, mntDir string) error {
-	manifest, err := images.Manifest(ctx, client.ContentStore(), image.Target(), platform)
-	if err != nil {
-		log.Fatalf("failed to get the manifest: %v\n", err)
-	}
-
-	for _, desc := range manifest.Layers {
-		log.Printf("extracting layer %s\n", desc.Digest.String())
-		layer, err := client.ContentStore().ReaderAt(ctx, desc)
-		if err != nil {
-			return err
-		}
-		if err := archive.Untar(content.NewReader(layer), mntDir, &archive.TarOptions{NoLchown: true}); err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-func createLoopDevice(rawFile, mntDir string) error {
-	f, err := renameio.TempFile("", rawFile)
-	if err != nil {
-		return err
-	}
-	defer f.Cleanup()
-
-	command := exec.Command("fallocate", "-l", "2G", f.Name())
-	if err := command.Run(); err != nil {
-		return fmt.Errorf("fallocate error: %s", err)
-	}
-
-	command = exec.Command("mkfs.ext4", "-F", f.Name())
-	if err := command.Run(); err != nil {
-		return fmt.Errorf("mkfs.ext4 error: %s", err)
-	}
-
-	f.CloseAtomicallyReplace()
-
-	command = exec.Command("mount", "-o", "loop", rawFile, mntDir)
-	if err := command.Run(); err != nil {
-		return fmt.Errorf("mount error: %s", err)
-	}
-	log.Printf("mounted %s on %s\n", rawFile, mntDir)
-	return nil
-}
-
-func detachLoopDevice(mntDir string) error {
-	log.Printf("umount %s\n", mntDir)
-	command := exec.Command("umount", mntDir)
-	return command.Run()
-}
-
-func resizeImage(rawFile string) error {
-	// let's bring the image to a more reasonable size. We do this by
-	// first running e2fsck on the image then we can resize the image.
-	command := exec.Command("/usr/bin/e2fsck", "-p", "-f", rawFile)
-	if err := command.Run(); err != nil {
-		return fmt.Errorf("e2fsck error: %s", err)
-	}
-
-	command = exec.Command("resize2fs", "-M", rawFile)
-	if err := command.Run(); err != nil {
-		return fmt.Errorf("resize2fs error: %s", err)
-	}
-	return nil
-}
-
-func extraFiles(mntDir string) error {
-	if err := writeToFile(filepath.Join(mntDir, "etc", "hosts"), "127.0.0.1\tlocalhost\n"); err != nil {
-		return err
-	}
-	if err := writeToFile(filepath.Join(mntDir, "etc", "resolv.conf"), "nameserver 192.168.0.1\n"); err != nil {
-		return err
-	}
-	return nil
-}
-
-func initScript(ctx context.Context, client *containerd.Client, image containerd.Image, mntDir string) error {
-	config, err := images.Config(ctx, client.ContentStore(), image.Target(), platform)
-	if err != nil {
-		return err
-	}
-
-	configBlob, err := content.ReadBlob(ctx, client.ContentStore(), config)
-	if err != nil {
-		return err
-	}
-	var imageSpec ocispec.Image
-	json.Unmarshal(configBlob, &imageSpec)
-	initCmd := strings.Join(imageSpec.Config.Cmd, " ")
-	initEnvs := imageSpec.Config.Env
-
-	initPath := filepath.Join(mntDir, "init.sh")
-	f, err := renameio.TempFile("", initPath)
-	if err != nil {
-		return err
-	}
-	defer f.Cleanup()
-
-	writer := bufio.NewWriter(f)
-	fmt.Fprintf(writer, "#!/bin/sh\n")
-	for _, env := range initEnvs {
-		fmt.Fprintf(writer, "export %s\n", env)
-	}
-	fmt.Fprintf(writer, "%s\n", initCmd)
-	writer.Flush()
-
-	f.CloseAtomicallyReplace()
-
-	mode := int(0755)
-	os.Chmod(initPath, os.FileMode(mode))
-	log.Printf("init script created")
-	return nil
-}
-
-func writeToFile(filepath string, content string) error {
-	if err := ioutil.WriteFile(filepath, []byte(content), 0644); err != nil {
-		return fmt.Errorf("writeToFile %s: %v", filepath, err)
-	}
-	return nil
-}
-
-func bootVM(ctx context.Context, rawImage, kernel, firecrackerBinary, metricsFifo string) {
-	vmmCtx, vmmCancel := context.WithCancel(ctx)
-	defer vmmCancel()
-
-	devices := make([]models.Drive, 1)
-	devices[0] = models.Drive{
-		DriveID:      firecracker.String("1"),
-		PathOnHost:   &rawImage,
-		IsRootDevice: firecracker.Bool(true),
-		IsReadOnly:   firecracker.Bool(false),
-	}
-	fcCfg := firecracker.Config{
-		LogLevel:        "debug",
-		SocketPath:      firecrackerSock,
-		KernelImagePath: kernel,
-		KernelArgs:      "console=ttyS0 reboot=k panic=1 acpi=off pci=off i8042.noaux i8042.nomux i8042.nopnp i8042.dumbkbd init=/init.sh random.trust_cpu=on",
-		Drives:          devices,
-		MetricsFifo:     metricsFifo,
-		MachineCfg: models.MachineConfiguration{
-			VcpuCount:   firecracker.Int64(1),
-			CPUTemplate: models.CPUTemplate("C3"),
-			HtEnabled:   firecracker.Bool(true),
-			MemSizeMib:  firecracker.Int64(512),
-		},
-		NetworkInterfaces: []firecracker.NetworkInterface{
-			{
-				CNIConfiguration: &firecracker.CNIConfiguration{
-					NetworkName: "c2vm",
-					IfName:      "eth0",
-				},
-			},
-		},
-	}
-
-	machineOpts := []firecracker.Opt{}
-
-	command := firecracker.VMCommandBuilder{}.
-		WithBin(firecrackerBinary).
-		WithSocketPath(fcCfg.SocketPath).
-		WithStdin(os.Stdin).
-		WithStdout(os.Stdout).
-		WithStderr(os.Stderr).
-		Build(ctx)
-	machineOpts = append(machineOpts, firecracker.WithProcessRunner(command))
-	m, err := firecracker.NewMachine(vmmCtx, fcCfg, machineOpts...)
-	if err != nil {
-		fmt.Printf("failed to start the vm: %+v\n", err)
-		os.Exit(1)
-	}
-
-	if err := m.Start(vmmCtx); err != nil {
-		fmt.Printf("failed to start the vm: %+v\n", err)
-		os.Exit(1)
-	}
-	defer m.StopVMM()
-
-	if err := m.Wait(vmmCtx); err != nil {
-		fmt.Printf("failed to start the vm: %+v\n", err)
-		os.Exit(1)
-	}
-	log.Print("Machine was started")
-}
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-12-25 18:23:35 +0000