local-server/cmd/dkl-local-server/boot-iso.go

171 lines
3.1 KiB
Go

package main
import (
"fmt"
"io"
"io/ioutil"
"log"
"os"
"os/exec"
"path/filepath"
"strconv"
"github.com/cespare/xxhash"
)
func buildBootISO(out io.Writer, ctx *renderContext) (err error) {
tempDir, err := ioutil.TempDir("/tmp", "iso-v2-")
if err != nil {
return
}
defer os.RemoveAll(tempDir)
buildRes := func(build func(out io.Writer, ctx *renderContext) error, dst string) (err error) {
log.Printf("iso-v2: building %s", dst)
outPath := filepath.Join(tempDir, dst)
if err = os.MkdirAll(filepath.Dir(outPath), 0755); err != nil {
return err
}
out, err := os.Create(outPath)
if err != nil {
return err
}
defer out.Close()
err = build(out, ctx)
if err != nil {
return
}
return err
}
err = func() (err error) {
// grub
if err = os.MkdirAll(filepath.Join(tempDir, "grub"), 0755); err != nil {
return
}
// create a tag file
bootstrapBytes, _, err := ctx.BootstrapConfig()
if err != nil {
return
}
h := xxhash.New()
fmt.Fprintln(h, ctx.Host.Kernel)
h.Write(bootstrapBytes)
tag := "dkl-" + strconv.FormatUint(h.Sum64(), 32) + ".tag"
f, err := os.Create(filepath.Join(tempDir, tag))
if err != nil {
return
}
f.Write([]byte("direktil marker file\n"))
f.Close()
err = ioutil.WriteFile(filepath.Join(tempDir, "grub", "grub.cfg"), []byte(`
search --set=root --file /`+tag+`
insmod all_video
set timeout=3
menuentry "Direktil" {
linux /vmlinuz `+ctx.CmdLine+`
initrd /initrd
}
`), 0644)
if err != nil {
return
}
coreImgPath := filepath.Join(tempDir, "grub", "core.img")
grubCfgPath := filepath.Join(tempDir, "grub", "grub.cfg")
cmd := exec.Command("grub-mkstandalone",
"--format=i386-pc",
"--output="+coreImgPath,
"--install-modules=linux normal iso9660 biosdisk memdisk search tar ls",
"--modules=linux normal iso9660 biosdisk search",
"--locales=",
"--fonts=",
"boot/grub/grub.cfg="+grubCfgPath,
)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := cmd.Run(); err != nil {
return err
}
defer os.Remove(coreImgPath)
defer os.Remove(grubCfgPath)
out, err := os.Create(filepath.Join(tempDir, "grub", "bios.img"))
if err != nil {
return err
}
defer out.Close()
b, err := ioutil.ReadFile("/usr/lib/grub/i386-pc/cdboot.img")
if err != nil {
return err
}
if _, err := out.Write(b); err != nil {
return err
}
b, err = ioutil.ReadFile(coreImgPath)
if err != nil {
return err
}
if _, err := out.Write(b); err != nil {
return err
}
return nil
}()
if err != nil {
return err
}
// kernel and initrd
buildRes(fetchKernel, "vmlinuz")
buildRes(buildInitrd, "initrd")
// build the ISO
mkisofs, err := exec.LookPath("genisoimage")
if err != nil {
mkisofs, err = exec.LookPath("mkisofs")
}
if err != nil {
return err
}
cmd := exec.Command(mkisofs,
"-quiet",
"-joliet",
"-joliet-long",
"-rock",
"-translation-table",
"-no-emul-boot",
"-boot-load-size", "4",
"-boot-info-table",
"-eltorito-boot", "grub/bios.img",
"-eltorito-catalog", "grub/boot.cat",
tempDir,
)
cmd.Stdout = out
cmd.Stderr = os.Stderr
return cmd.Run()
}