zsysctl: add flag to support creating an encrypted dataset

Create an encrypted dataset with raw type keyfile when particular
flag is given to userdata create.

For example:
  $ zsysctl userdata create -e myuser /home/myuser

Signed-off-by: Crag Wang <crag.wang@dell.com>

cmd/zsysd/client/userdata.go

@@ -23,7 +23,7 @@ var (
  Use: "create USER HOME_DIRECTORY",
  Short: i18n.G("Create a new home user dataset via an user dataset (if doesn't exist) creation"),
  Args: cobra.ExactArgs(2),
- Run: func(cmd *cobra.Command, args []string) { cmdErr = createUserData(args[0], args[1]) },
+ Run: func(cmd *cobra.Command, args []string) { cmdErr = createUserData(args[0], args[1], encryptHome) },
  }
  userdataRenameCmd = &cobra.Command{
  Use: "set-home OLD_HOME NEW_HOME",
@@ -40,20 +40,22 @@ var (
 )
 
 var (
- removeHome bool
+ removeHome bool
+ encryptHome bool
 )
 
 func init() {
  rootCmd.AddCommand(userdataCmd)
  userdataCmd.AddCommand(userdataCreateCmd)
  userdataCmd.AddCommand(userdataRenameCmd)
  userdataCmd.AddCommand(userdataDissociateCmd)
+ userdataCreateCmd.Flags().BoolVarP(&encryptHome, "encrypt", "e", false, i18n.G("Encrypt home directory in associatation with keyfile"))
  userdataDissociateCmd.Flags().BoolVarP(&removeHome, "remove", "r", false, i18n.G("Empty home directory content if not associated to any machine state"))
 }
 
 // createUserData creates a new userdata for user and set it to homepath on current zsys system.
 // if the user already exists for a dataset attached to the current system, set its mountpoint to homepath.
-func createUserData(user, homepath string) (err error) {
+func createUserData(user, homepath string, encryptHome bool) (err error) {
  client, err := newClient()
  if err != nil {
  return err
@@ -63,7 +65,7 @@ func createUserData(user, homepath string) (err error) {
  ctx, cancel, reset := contextWithResettableTimeout(client.Ctx, config.DefaultClientTimeout)
  defer cancel()
 
- stream, err := client.CreateUserData(ctx, &zsys.CreateUserDataRequest{User: user, Homepath: homepath})
+ stream, err := client.CreateUserData(ctx, &zsys.CreateUserDataRequest{User: user, Homepath: homepath, EncryptHome: encryptHome})
  if err = checkConn(err, reset); err != nil {
  return err
  }

internal/daemon/userdata.go

@@ -19,13 +19,14 @@ func (s *Server) CreateUserData(req *zsys.CreateUserDataRequest, stream zsys.Zsy
  }
 
  user := req.GetUser()
+ encryptHome := req.GetEncryptHome()
  homepath := req.GetHomepath()
  s.RWRequest.Lock()
  defer s.RWRequest.Unlock()
 
  log.Infof(stream.Context(), i18n.G("Create user dataset for %q on %q"), user, homepath)
 
- if err := s.Machines.CreateUserData(stream.Context(), user, homepath); err != nil {
+ if err := s.Machines.CreateUserData(stream.Context(), user, homepath, encryptHome); err != nil {
  return fmt.Errorf(i18n.G("couldn't create userdataset for %q: ")+config.ErrorFormat, homepath, err)
  }
  return nil

internal/machines/machines_test.go

@@ -617,10 +617,11 @@ func TestUpdateLastUsed(t *testing.T) {
 func TestCreateUserData(t *testing.T) {
  t.Parallel()
  tests := map[string]struct {
- def string
- user string
- homePath string
- cmdline string
+ def string
+ user string
+ homePath string
+ encryptHome bool
+ cmdline string
 
  setPropertyErr bool
  createErr bool
@@ -633,6 +634,7 @@ func TestCreateUserData(t *testing.T) {
  "One machine add user dataset without userdata": {def: "m_without_userdata.yaml"},
  "One machine with no user, only userdata": {def: "m_with_userdata_only.yaml"},
  "No attached userdata": {def: "m_no_attached_userdata_first_pool.yaml"},
+ "One machine add user encrypted home dataset": {def: "m_with_userdata.yaml", encryptHome: true},
 
  // Second pool cases
  "User dataset on other pool": {def: "m_with_userdata_on_other_pool.yaml"},
@@ -685,7 +687,7 @@ func TestCreateUserData(t *testing.T) {
  lzfs.ErrOnScan(tc.scanErr)
  lzfs.ErrOnSetProperty(tc.setPropertyErr)
 
- err = ms.CreateUserData(context.Background(), getDefaultValue(tc.user, "userfoo"), getDefaultValue(tc.homePath, "/home/foo"))
+ err = ms.CreateUserData(context.Background(), getDefaultValue(tc.user, "userfoo"), getDefaultValue(tc.homePath, "/home/foo"), tc.encryptHome)
  if err != nil {
  if !tc.wantErr {
  t.Fatalf("expected no error but got: %v", err)

internal/machines/userdata.go

@@ -22,7 +22,7 @@ import (
 
 // CreateUserData creates a new dataset for homepath and attach to current system.
 // It creates intermediates user datasets if needed.
-func (ms *Machines) CreateUserData(ctx context.Context, user, homepath string) error {
+func (ms *Machines) CreateUserData(ctx context.Context, user, homepath string, encryptHome bool) error {
  if !ms.current.isZsys() {
  return errors.New(i18n.G("Current machine isn't Zsys, nothing to create"))
  }
@@ -81,14 +81,18 @@ selectUserDataset:
  userdatasetRoot = filepath.Join(p, zfs.UserdataPrefix)
 
  // Create parent USERDATA
- if err := t.Create(userdatasetRoot, "/", "off"); err != nil {
+ if err := t.Create(userdatasetRoot, "/", "off", false); err != nil {
  cancel()
  return fmt.Errorf(i18n.G("couldn't create user data embedder dataset: ")+config.ErrorFormat, err)
  }
  }
 
  userdataset := filepath.Join(userdatasetRoot, fmt.Sprintf("%s_%s", user, t.Zfs.GenerateID(6)))
- if err := t.Create(userdataset, homepath, "on"); err != nil {
+ var canmountProp string = "on"
+ if encryptHome {
+ canmountProp = "noauto"
+ }
+ if err := t.Create(userdataset, homepath, canmountProp, encryptHome); err != nil {
  cancel()
  return err
  }

internal/zfs/libzfs/adapter.go

@@ -47,6 +47,12 @@ const (
  DatasetPropCanmount = golibzfs.DatasetPropCanmount
  // DatasetPropMountpoint is the mountpoint of the dataset
  DatasetPropMountpoint = golibzfs.DatasetPropMountpoint
+ // DatasetPropEncryption is the encryption of the dataste
+ DatasetPropEncryption = golibzfs.DatasetPropEncryption
+ // DatasetPropEncryption is the encryption of the dataste
+ DatasetPropKeyLocation = golibzfs.DatasetPropKeyLocation
+ // DatasetPropEncryption is the encryption of the dataste
+ DatasetPropKeyFormat = golibzfs.DatasetPropKeyFormat
  // DatasetPropOrigin is the origin of the dataset
  DatasetPropOrigin = golibzfs.DatasetPropOrigin
  // DatasetPropMounted is the mounted property for the dataset

internal/zfs/zfs.go

@@ -2,7 +2,10 @@ package zfs
 
 import (
  "context"
+ "crypto/rand"
  "fmt"
+ "io"
+ "io/ioutil"
  "path/filepath"
  "strings"
 
@@ -315,16 +318,34 @@ func (t *nestedTransaction) Done(err *error) {
  t.parent.reverts = append(t.parent.reverts, t.reverts...)
 }
 
+func genRandBytes(keyLength int) []byte {
+ keytext := make([]byte, keyLength)
+ if _, err := io.ReadFull(rand.Reader, keytext); err != nil {
+ panic(err.Error())
+ }
+ return keytext
+}
+
 // Create creates a dataset for that path.
-func (t *Transaction) Create(path, mountpoint, canmount string) error {
+func (t *Transaction) Create(path, mountpoint, canmount string, encryption bool) error {
  t.checkValid()
 
- log.Debugf(t.ctx, i18n.G("ZFS: trying to Create %q with mountpoint %q"), path, mountpoint)
+ log.Debugf(t.ctx, i18n.G("ZFS: trying to Create %q with mountpoint %q; encryption=%q"), path, mountpoint, fmt.Sprint(encryption))
 
  props := make(map[libzfs.Prop]libzfs.Property)
  if mountpoint != "" {
  props[libzfs.DatasetPropMountpoint] = libzfs.Property{Value: mountpoint}
  }
+ if encryption {
+ var keyfilePath string = filepath.Join(filepath.Dir(mountpoint), filepath.Base(mountpoint)+".keyfile")
+ if err := ioutil.WriteFile(keyfilePath, genRandBytes(32), 0400); err != nil {
+ panic(err.Error())
+ }
+
+ props[libzfs.DatasetPropEncryption] = libzfs.Property{Value: "aes-256-gcm"}
+ props[libzfs.DatasetPropKeyLocation] = libzfs.Property{Value: "file://" + keyfilePath}
+ props[libzfs.DatasetPropKeyFormat] = libzfs.Property{Value: "raw"}
+ }
  props[libzfs.DatasetPropCanmount] = libzfs.Property{Value: canmount}
 
  dZFS, err := t.Zfs.libzfs.DatasetCreate(path, libzfs.DatasetTypeFilesystem, props)

zsys.proto

@@ -47,6 +47,7 @@ message VersionResponse {
 message CreateUserDataRequest {
  string user = 1;
  string homepath = 2;
+ bool encryptHome = 3;
 }
 
 message ChangeHomeOnUserDataRequest {