move initrd

cmd/dkl-initrd-init/main.go

@@ -1,190 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"io/ioutil"
-	"log"
-	"os"
-	"os/exec"
-	"path/filepath"
-	"strings"
-	"syscall"
-	"time"
-
-	yaml "gopkg.in/yaml.v2"
-	"novit.nc/direktil/pkg/sysfs"
-)
-
-const (
-	// VERSION is the current version of init
-	VERSION = "Direktil init v0.1"
-
-	rootMountFlags  = 0
-	bootMountFlags  = syscall.MS_NOEXEC | syscall.MS_NODEV | syscall.MS_NOSUID | syscall.MS_RDONLY
-	layerMountFlags = syscall.MS_RDONLY
-)
-
-var (
-	bootVersion string
-)
-
-type config struct {
-	Layers []string `yaml:"layers"`
-}
-
-func main() {
-	log.Print("Welcome to ", VERSION)
-
-	// essential mounts
-	mount("none", "/proc", "proc", 0, "")
-	mount("none", "/sys", "sysfs", 0, "")
-	mount("none", "/dev", "devtmpfs", 0, "")
-
-	// get the "boot version"
-	bootVersion = param("version", "current")
-	log.Printf("booting system %q", bootVersion)
-
-	// find and mount /boot
-	bootMatch := param("boot", "")
-	if bootMatch != "" {
-		bootFS := param("boot.fs", "vfat")
-		for i := 0; ; i++ {
-			devNames := sysfs.DeviceByProperty("block", bootMatch)
-
-			if len(devNames) == 0 {
-				if i > 30 {
-					fatal("boot partition not found after 30s")
-				}
-				log.Print("boot partition not found, retrying")
-				time.Sleep(1 * time.Second)
-				continue
-			}
-
-			devFile := filepath.Join("/dev", devNames[0])
-
-			log.Print("boot partition found: ", devFile)
-
-			mount(devFile, "/boot", bootFS, bootMountFlags, "")
-			break
-		}
-	} else {
-		log.Print("Assuming /boot is already populated.")
-	}
-
-	// load config
-	cfgPath := param("config", "/boot/config.yaml")
-
-	cfgBytes, err := ioutil.ReadFile(cfgPath)
-	if err != nil {
-		fatalf("failed to read %s: %v", cfgPath, err)
-	}
-
-	cfg := &config{}
-	if err := yaml.Unmarshal(cfgBytes, cfg); err != nil {
-		fatal("failed to load config: ", err)
-	}
-
-	// mount layers
-	if len(cfg.Layers) == 0 {
-		fatal("no layers configured!")
-	}
-
-	log.Printf("wanted layers: %q", cfg.Layers)
-
-	lowers := make([]string, len(cfg.Layers))
-	for i, layer := range cfg.Layers {
-		path := layerPath(layer)
-
-		info, err := os.Stat(path)
-		if err != nil {
-			fatal(err)
-		}
-
-		log.Printf("layer %s found (%d bytes)", layer, info.Size())
-
-		dir := "/layers/" + layer
-
-		lowers[i] = dir
-
-		loopDev := fmt.Sprintf("/dev/loop%d", i)
-		losetup(loopDev, path)
-
-		mount(loopDev, dir, "squashfs", layerMountFlags, "")
-	}
-
-	// prepare system root
-	mount("mem", "/changes", "tmpfs", 0, "")
-
-	mkdir("/changes/workdir", 0755)
-	mkdir("/changes/upperdir", 0755)
-
-	mount("overlay", "/system", "overlay", rootMountFlags,
-		"lowerdir="+strings.Join(lowers, ":")+",upperdir=/changes/upperdir,workdir=/changes/workdir")
-	mount("/boot", "/system/boot", "", syscall.MS_BIND, "")
-
-	// - write configuration
-	log.Print("writing /config.yaml")
-	if err := ioutil.WriteFile("/system/config.yaml", cfgBytes, 0600); err != nil {
-		fatal("failed: ", err)
-	}
-
-	// clean zombies
-	cleanZombies()
-
-	// switch root
-	log.Print("switching root")
-	err = syscall.Exec("/sbin/switch_root", []string{"switch_root", "/system", "/sbin/init"}, os.Environ())
-	if err != nil {
-		log.Print("switch_root failed: ", err)
-		select {}
-	}
-}
-
-func layerPath(name string) string {
-	return fmt.Sprintf("/boot/%s/layers/%s.fs", bootVersion, name)
-}
-
-func fatal(v ...interface{}) {
-	log.Print("*** FATAL ***")
-	log.Print(v...)
-	dropToShell()
-}
-
-func fatalf(pattern string, v ...interface{}) {
-	log.Print("*** FATAL ***")
-	log.Printf(pattern, v...)
-	dropToShell()
-}
-
-func dropToShell() {
-	err := syscall.Exec("/bin/sh", []string{"/bin/sh"}, os.Environ())
-	log.Print("shell drop failed: ", err)
-	select {}
-}
-
-func losetup(dev, file string) {
-	run("/sbin/losetup", dev, file)
-}
-
-func run(cmd string, args ...string) {
-	if output, err := exec.Command(cmd, args...).CombinedOutput(); err != nil {
-		fatalf("command %s %q failed: %v\n%s", cmd, args, err, string(output))
-	}
-}
-
-func mkdir(dir string, mode os.FileMode) {
-	if err := os.MkdirAll(dir, mode); err != nil {
-		fatalf("mkdir %q failed: %v", dir, err)
-	}
-}
-
-func mount(source, target, fstype string, flags uintptr, data string) {
-	if _, err := os.Stat(target); os.IsNotExist(err) {
-		mkdir(target, 0755)
-	}
-
-	if err := syscall.Mount(source, target, fstype, flags, data); err != nil {
-		fatalf("mount %q %q -t %q -o %q failed: %v", source, target, fstype, data, err)
-	}
-	log.Printf("mounted %q", target)
-}

cmd/dkl-initrd-init/params.go

@@ -1,23 +0,0 @@
-package main
-
-import (
-	"io/ioutil"
-	"strings"
-)
-
-func param(name, defaultValue string) (value string) {
-	ba, err := ioutil.ReadFile("/proc/cmdline")
-	if err != nil {
-		fatal("could not read /proc/cmdline: ", err)
-	}
-
-	prefix := "direktil." + name + "="
-
-	for _, part := range strings.Split(string(ba), " ") {
-		if strings.HasPrefix(part, prefix) {
-			return strings.TrimSpace(part[len(prefix):])
-		}
-	}
-
-	return defaultValue
-}

cmd/dkl-initrd-init/zombies.go

@@ -1,24 +0,0 @@
-package main
-
-import (
-	"log"
-	"syscall"
-)
-
-func cleanZombies() {
-	var wstatus syscall.WaitStatus
-
-	for {
-		pid, err := syscall.Wait4(-1, &wstatus, 0, nil)
-		switch err {
-		case nil:
-			log.Printf("collected PID %v", pid)
-
-		case syscall.ECHILD:
-			return
-
-		default:
-			log.Printf("unknown error: %v", err)
-		}
-	}
-}