// Copyright 2022 Linka Cloud All rights reserved. // // 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 d2vm import ( "context" "fmt" "os" exec2 "os/exec" "path/filepath" "strings" "github.com/c2h5oh/datasize" "github.com/sirupsen/logrus" "go.uber.org/multierr" "go.linka.cloud/d2vm/pkg/exec" ) const ( hosts = `127.0.0.1 localhost # The following lines are desirable for IPv6 capable hosts ::1 ip6-localhost ip6-loopback fe00::0 ip6-localnet ff00::0 ip6-mcastprefix ff02::1 ip6-allnodes ff02::2 ip6-allrouters ff02::3 ip6-allhosts ` syslinuxCfgUbuntu = `DEFAULT linux SAY Now booting the kernel from SYSLINUX... LABEL linux KERNEL /boot/vmlinuz APPEND ro root=UUID=%s initrd=/boot/initrd.img net.ifnames=0 console=tty0 console=ttyS0,115200n8 %s ` syslinuxCfgDebian = `DEFAULT linux SAY Now booting the kernel from SYSLINUX... LABEL linux KERNEL /vmlinuz APPEND ro root=UUID=%s initrd=/initrd.img net.ifnames=0 console=tty0 console=ttyS0,115200n8 %s ` syslinuxCfgAlpine = `DEFAULT linux SAY Now booting the kernel from SYSLINUX... LABEL linux KERNEL /boot/vmlinuz-virt APPEND ro root=UUID=%s rootfstype=ext4 initrd=/boot/initramfs-virt console=ttyS0,115200 %s ` syslinuxCfgCentOS = `DEFAULT linux SAY Now booting the kernel from SYSLINUX... LABEL linux KERNEL /boot/vmlinuz APPEND ro root=UUID=%s initrd=/boot/initrd.img net.ifnames=0 console=tty0 console=ttyS0,115200n8 %s ` ) var ( formats = []string{"qcow2", "qed", "raw", "vdi", "vhd", "vmdk"} mbrPaths = []string{ // debian path "/usr/lib/syslinux/mbr/mbr.bin", // ubuntu path "/usr/lib/EXTLINUX/mbr.bin", // alpine path "/usr/share/syslinux/mbr.bin", // centos path "/usr/share/syslinux/mbr.bin", // archlinux path "/usr/lib/syslinux/bios/mbr.bin", } ) const ( perm os.FileMode = 0644 ) func sysconfig(osRelease OSRelease) (string, error) { switch osRelease.ID { case ReleaseUbuntu: if osRelease.VersionID < "20.04" { return syslinuxCfgDebian, nil } return syslinuxCfgUbuntu, nil case ReleaseDebian: return syslinuxCfgDebian, nil case ReleaseAlpine: return syslinuxCfgAlpine, nil case ReleaseCentOS: return syslinuxCfgCentOS, nil default: return "", fmt.Errorf("%s: distribution not supported", osRelease.ID) } } type builder struct { osRelease OSRelease src string img *image diskRaw string diskOut string format string size int64 mntPoint string mbrPath string loDevice string loPart string diskUUD string cmdLineExtra string } func NewBuilder(ctx context.Context, workdir, imgTag, disk string, size int64, osRelease OSRelease, format string, cmdLineExtra string) (*builder, error) { if err := checkDependencies(); err != nil { return nil, err } f := strings.ToLower(format) valid := false for _, v := range formats { if valid = v == f; valid { break } } if !valid { return nil, fmt.Errorf("invalid format: %s valid formats are: %s", f, strings.Join(formats, " ")) } mbrBin := "" for _, v := range mbrPaths { if _, err := os.Stat(v); err == nil { mbrBin = v break } } if mbrBin == "" { return nil, fmt.Errorf("unable to find syslinux's mbr.bin path") } if size == 0 { size = 10 * int64(datasize.GB) } if disk == "" { disk = "disk0" } img, err := NewImage(ctx, imgTag, workdir) if err != nil { return nil, err } // i, err := os.Stat(imgTar) // if err != nil { // return nil, err // } // if i.Size() > size { // s := datasize.ByteSize(math.Ceil(datasize.ByteSize(i.Size()).GBytes())) * datasize.GB // logrus.Warnf("%s is smaller than rootfs size, using %s", datasize.ByteSize(size), s) // size = int64(s) // } b := &builder{ osRelease: osRelease, img: img, diskRaw: filepath.Join(workdir, disk+".d2vm.raw"), diskOut: filepath.Join(workdir, disk+"."+format), format: f, size: size, mbrPath: mbrBin, mntPoint: filepath.Join(workdir, "/mnt"), cmdLineExtra: cmdLineExtra, } if err := os.MkdirAll(b.mntPoint, os.ModePerm); err != nil { return nil, err } return b, nil } func (b *builder) Build(ctx context.Context) (err error) { defer func() { if err == nil { return } logrus.WithError(err).Error("Build failed") if err := b.unmountImg(context.Background()); err != nil { logrus.WithError(err).Error("failed to unmount") } if err := b.cleanUp(context.Background()); err != nil { logrus.WithError(err).Error("failed to cleanup") } }() if err = b.cleanUp(ctx); err != nil { return err } if err = b.makeImg(ctx); err != nil { return err } if err = b.mountImg(ctx); err != nil { return err } if err = b.copyRootFS(ctx); err != nil { return err } if err = b.setupRootFS(ctx); err != nil { return err } if err = b.installKernel(ctx); err != nil { return err } if err = b.unmountImg(ctx); err != nil { return err } if err = b.setupMBR(ctx); err != nil { return err } if err = b.convert2Img(ctx); err != nil { return err } if err = b.cleanUp(ctx); err != nil { return err } return nil } func (b *builder) cleanUp(ctx context.Context) error { return os.RemoveAll(b.diskRaw) } func (b *builder) makeImg(ctx context.Context) error { ctx, cancel := context.WithCancel(ctx) defer cancel() logrus.Infof("creating raw image") if err := block(b.diskRaw, b.size); err != nil { return err } if err := exec.Run(ctx, "parted", "-s", b.diskRaw, "mklabel", "msdos", "mkpart", "primary", "1Mib", "100%", "set", "1", "boot", "on"); err != nil { return err } return nil } func (b *builder) mountImg(ctx context.Context) error { logrus.Infof("mounting raw image") o, _, err := exec.RunOut(ctx, "losetup", "--show", "-f", b.diskRaw) if err != nil { return err } b.loDevice = strings.TrimSuffix(o, "\n") if err := exec.Run(ctx, "partprobe", b.loDevice); err != nil { return err } b.loPart = fmt.Sprintf("%sp1", b.loDevice) logrus.Infof("creating raw image file system") if err := exec.Run(ctx, "mkfs.ext4", b.loPart); err != nil { return err } if err := exec.Run(ctx, "mount", b.loPart, b.mntPoint); err != nil { return err } return nil } func (b *builder) unmountImg(ctx context.Context) error { logrus.Infof("unmounting raw image") var merr error if err := exec.Run(ctx, "umount", b.mntPoint); err != nil { merr = multierr.Append(merr, err) } if err := exec.Run(ctx, "losetup", "-d", b.loDevice); err != nil { merr = multierr.Append(merr, err) } return merr } func (b *builder) copyRootFS(ctx context.Context) error { logrus.Infof("copying rootfs to raw image") if err := b.img.Flatten(ctx, b.mntPoint); err != nil { return err } return nil } func (b *builder) setupRootFS(ctx context.Context) error { logrus.Infof("setting up rootfs") o, _, err := exec.RunOut(ctx, "blkid", "-s", "UUID", "-o", "value", b.loPart) if err != nil { return err } b.diskUUD = strings.TrimSuffix(o, "\n") fstab := fmt.Sprintf("UUID=%s / ext4 errors=remount-ro 0 1\n", b.diskUUD) if err := b.chWriteFile("/etc/fstab", fstab, perm); err != nil { return err } if err := b.chWriteFileIfNotExist("/etc/resolv.conf", "nameserver 8.8.8.8", 0644); err != nil { return err } if err := b.chWriteFileIfNotExist("/etc/hostname", "localhost", perm); err != nil { return err } if err := b.chWriteFileIfNotExist("/etc/hosts", hosts, perm); err != nil { return err } // TODO(adphi): is it the righ fix ? if err := os.RemoveAll("/usr/sbin/policy-rc.d"); err != nil { return err } if err := os.RemoveAll(b.chPath("/.dockerenv")); err != nil { return err } if b.osRelease.ID != ReleaseAlpine { return nil } by, err := os.ReadFile(b.chPath("/etc/inittab")) if err != nil { return err } by = append(by, []byte("\n"+"ttyS0::respawn:/sbin/getty -L ttyS0 115200 vt100\n")...) if err := b.chWriteFile("/etc/inittab", string(by), perm); err != nil { return err } if err := b.chWriteFileIfNotExist("/etc/network/interfaces", "", perm); err != nil { return err } return nil } func (b *builder) installKernel(ctx context.Context) error { logrus.Infof("installing linux kernel") if err := exec.Run(ctx, "extlinux", "--install", b.chPath("/boot")); err != nil { return err } sysconfig, err := sysconfig(b.osRelease) if err != nil { return err } if err := b.chWriteFile("/boot/syslinux.cfg", fmt.Sprintf(sysconfig, b.diskUUD, b.cmdLineExtra), perm); err != nil { return err } return nil } func (b *builder) setupMBR(ctx context.Context) error { logrus.Infof("writing MBR") if err := exec.Run(ctx, "dd", fmt.Sprintf("if=%s", b.mbrPath), fmt.Sprintf("of=%s", b.diskRaw), "bs=440", "count=1", "conv=notrunc"); err != nil { return err } return nil } func (b *builder) convert2Img(ctx context.Context) error { logrus.Infof("converting to %s", b.format) return exec.Run(ctx, "qemu-img", "convert", b.diskRaw, "-O", b.format, b.diskOut) } func (b *builder) chWriteFile(path string, content string, perm os.FileMode) error { return os.WriteFile(b.chPath(path), []byte(content), perm) } func (b *builder) chWriteFileIfNotExist(path string, content string, perm os.FileMode) error { if i, err := os.Stat(b.chPath(path)); err == nil && i.Size() != 0 { return nil } return os.WriteFile(b.chPath(path), []byte(content), perm) } func (b *builder) chPath(path string) string { return fmt.Sprintf("%s%s", b.mntPoint, path) } func (b *builder) Close() error { return b.img.Close() } func block(path string, size int64) error { f, err := os.Create(path) if err != nil { return err } defer f.Close() return f.Truncate(size) } func checkDependencies() error { var merr error for _, v := range []string{"mount", "blkid", "tar", "losetup", "parted", "partprobe", "qemu-img", "extlinux", "dd", "mkfs"} { if _, err := exec2.LookPath(v); err != nil { merr = multierr.Append(merr, err) } } return merr } func OutputFormats() []string { return formats[:] }