libgocryptfs/pathfs_frontend/fs.go
Jakob Unterwurzacher 889ae90081 Add pathfs frontend (uses go-fuse instead of bazil-fuse), part I
Currently fails main_test.go, will be fixed in part II
2015-09-08 00:55:03 +02:00

167 lines
5.3 KiB
Go

package pathfs_frontend
import (
"os"
"path/filepath"
"time"
"fmt"
"github.com/hanwen/go-fuse/fuse"
"github.com/hanwen/go-fuse/fuse/nodefs"
"github.com/hanwen/go-fuse/fuse/pathfs"
"github.com/rfjakob/gocryptfs/cryptfs"
)
type FS struct {
*cryptfs.CryptFS
pathfs.FileSystem // loopbackFileSystem
backing string // Backing directory
}
// Encrypted FUSE overlay filesystem
func NewFS(key [16]byte, backing string, useOpenssl bool) *FS {
return &FS{
CryptFS: cryptfs.NewCryptFS(key, useOpenssl),
FileSystem: pathfs.NewLoopbackFileSystem(backing),
backing: backing,
}
}
// GetPath - get the absolute path of the backing file
func (fs *FS) GetPath(relPath string) string {
return filepath.Join(fs.backing, fs.EncryptPath(relPath))
}
func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
a, status := fs.FileSystem.GetAttr(fs.EncryptPath(name), context)
if a == nil {
return a, status
}
a.Size = fs.PlainSize(a.Size)
return a, status
}
func (fs *FS) OpenDir(name string, context *fuse.Context) ([]fuse.DirEntry, fuse.Status) {
cipherEntries, status := fs.FileSystem.OpenDir(fs.EncryptPath(name), context);
var plain []fuse.DirEntry
var skipped int
if cipherEntries != nil {
for i := range cipherEntries {
n, err := fs.DecryptPath(cipherEntries[i].Name)
if err != nil {
fmt.Printf("Skipping invalid filename \"%s\": %s\n", cipherEntries[i].Name, err)
skipped++
continue
}
cipherEntries[i].Name = n
plain = append(plain, cipherEntries[i])
}
}
return plain, status
}
// We always need read access to do read-modify-write cycles
func (fs *FS) mangleOpenFlags(flags uint32) (newFlags int, writeOnly bool) {
newFlags = int(flags)
if newFlags & os.O_WRONLY > 0 {
writeOnly = true
newFlags = newFlags ^ os.O_WRONLY | os.O_RDWR
}
// We also cannot open the file in append mode, we need to seek back for RMW
newFlags = newFlags &^ os.O_APPEND
return newFlags, writeOnly
}
func (fs *FS) Open(name string, flags uint32, context *fuse.Context) (fuseFile nodefs.File, status fuse.Status) {
cryptfs.Debug.Printf("Open(%s)\n", name)
iflags, writeOnly := fs.mangleOpenFlags(flags)
f, err := os.OpenFile(fs.GetPath(name), iflags, 0666)
if err != nil {
return nil, fuse.ToStatus(err)
}
return NewFile(f, writeOnly, fs.CryptFS), fuse.OK
}
func (fs *FS) Create(path string, flags uint32, mode uint32, context *fuse.Context) (fuseFile nodefs.File, code fuse.Status) {
iflags, writeOnly := fs.mangleOpenFlags(flags)
f, err := os.OpenFile(fs.GetPath(path), iflags|os.O_CREATE, os.FileMode(mode))
if err != nil {
return nil, fuse.ToStatus(err)
}
return NewFile(f, writeOnly, fs.CryptFS), fuse.OK
}
func (fs *FS) Chmod(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Chmod(fs.EncryptPath(path), mode, context)
}
func (fs *FS) Chown(path string, uid uint32, gid uint32, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Chmod(fs.EncryptPath(path), gid, context)
}
func (fs *FS) Truncate(path string, offset uint64, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Truncate(fs.EncryptPath(path), offset, context)
}
func (fs *FS) Utimens(path string, Atime *time.Time, Mtime *time.Time, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Utimens(fs.EncryptPath(path), Atime, Mtime, context)
}
func (fs *FS) Readlink(name string, context *fuse.Context) (out string, code fuse.Status) {
return fs.FileSystem.Readlink(fs.EncryptPath(name), context)
}
func (fs *FS) Mknod(name string, mode uint32, dev uint32, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Mknod(fs.EncryptPath(name), mode, dev, context)
}
func (fs *FS) Mkdir(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Mkdir(fs.EncryptPath(path), mode, context)
}
func (fs *FS) Unlink(name string, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Unlink(fs.EncryptPath(name), context)
}
func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Rmdir(fs.EncryptPath(name), context)
}
func (fs *FS) Symlink(pointedTo string, linkName string, context *fuse.Context) (code fuse.Status) {
// TODO symlink encryption
return fs.FileSystem.Symlink(fs.EncryptPath(pointedTo), fs.EncryptPath(linkName), context)
}
func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (codee fuse.Status) {
return fs.FileSystem.Rename(fs.EncryptPath(oldPath), fs.EncryptPath(newPath), context)
}
func (fs *FS) Link(orig string, newName string, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Link(fs.EncryptPath(orig), fs.EncryptPath(newName), context)
}
func (fs *FS) Access(name string, mode uint32, context *fuse.Context) (code fuse.Status) {
return fs.FileSystem.Access(fs.EncryptPath(name), mode, context)
}
func (fs *FS) GetXAttr(name string, attr string, context *fuse.Context) ([]byte, fuse.Status) {
return nil, fuse.ENOSYS
}
func (fs *FS) SetXAttr(name string, attr string, data []byte, flags int, context *fuse.Context) fuse.Status {
return fuse.ENOSYS
}
func (fs *FS) ListXAttr(name string, context *fuse.Context) ([]string, fuse.Status) {
return nil, fuse.ENOSYS
}
func (fs *FS) RemoveXAttr(name string, attr string, context *fuse.Context) fuse.Status {
return fuse.ENOSYS
}