Move pathfs_frontend to internal/fusefrontend

"git status" for reference:

renamed:    pathfs_frontend/args.go -> internal/fusefrontend/args.go
renamed:    pathfs_frontend/compat_darwin.go -> internal/fusefrontend/compat_darwin.go
renamed:    pathfs_frontend/compat_linux.go -> internal/fusefrontend/compat_linux.go
renamed:    pathfs_frontend/file.go -> internal/fusefrontend/file.go
renamed:    pathfs_frontend/file_holes.go -> internal/fusefrontend/file_holes.go
renamed:    pathfs_frontend/fs.go -> internal/fusefrontend/fs.go
renamed:    pathfs_frontend/fs_dir.go -> internal/fusefrontend/fs_dir.go
renamed:    pathfs_frontend/names.go -> internal/fusefrontend/names.go
renamed:    pathfs_frontend/write_lock.go -> internal/fusefrontend/write_lock.go
modified:   main.go

9 files changed, 0 insertions, 1228 deletions

diff --git a/pathfs_frontend/args.go b/pathfs_frontend/args.go
deleted file mode 100644
index 91f9ba7..0000000
--- a/pathfs_frontend/args.go
+++ /dev/null
@@ -1,12 +0,0 @@
-package pathfs_frontend
-
-// Container for arguments that are passed from main() to pathfs_frontend
-type Args struct {
-	Masterkey      []byte
-	Cipherdir      string
-	OpenSSL        bool
-	PlaintextNames bool
-	DirIV          bool
-	EMENames       bool
-	GCMIV128       bool
-}
diff --git a/pathfs_frontend/compat_darwin.go b/pathfs_frontend/compat_darwin.go
deleted file mode 100644
index 3ddb50d..0000000
--- a/pathfs_frontend/compat_darwin.go
+++ /dev/null
@@ -1,12 +0,0 @@
-package pathfs_frontend
-
-// prealloc - preallocate space without changing the file size. This prevents
-// us from running out of space in the middle of an operation.
-func prealloc(fd int, off int64, len int64) (err error) {
-	//
-	// Sorry, fallocate is not available on OSX at all and
-	// fcntl F_PREALLOCATE is not accessible from Go.
-	//
-	// See https://github.com/rfjakob/gocryptfs/issues/18 if you want to help.
-	return nil
-}
diff --git a/pathfs_frontend/compat_linux.go b/pathfs_frontend/compat_linux.go
deleted file mode 100644
index 7ed3c74..0000000
--- a/pathfs_frontend/compat_linux.go
+++ /dev/null
@@ -1,18 +0,0 @@
-package pathfs_frontend
-
-import "syscall"
-
-// prealloc - preallocate space without changing the file size. This prevents
-// us from running out of space in the middle of an operation.
-func prealloc(fd int, off int64, len int64) (err error) {
-	for {
-		err = syscall.Fallocate(fd, FALLOC_FL_KEEP_SIZE, off, len)
-		if err == syscall.EINTR {
-			// fallocate, like many syscalls, can return EINTR. This is not an
-			// error and just signifies that the operation was interrupted by a
-			// signal and we should try again.
-			continue
-		}
-		return err
-	}
-}
diff --git a/pathfs_frontend/file.go b/pathfs_frontend/file.go
deleted file mode 100644
index 387eb35..0000000
--- a/pathfs_frontend/file.go
+++ /dev/null
@@ -1,501 +0,0 @@
-package pathfs_frontend
-
-// FUSE operations on file handles
-
-import (
-	"bytes"
-	"fmt"
-	"io"
-	"os"
-	"sync"
-	"syscall"
-	"time"
-
-	"github.com/hanwen/go-fuse/fuse"
-	"github.com/hanwen/go-fuse/fuse/nodefs"
-
-	"github.com/rfjakob/gocryptfs/internal/contentenc"
-	"github.com/rfjakob/gocryptfs/internal/toggledlog"
-)
-
-// File - based on loopbackFile in go-fuse/fuse/nodefs/files.go
-type file struct {
-	fd *os.File
-
-	// fdLock prevents the fd to be closed while we are in the middle of
-	// an operation.
-	// Every FUSE entrypoint should RLock(). The only user of Lock() is
-	// Release(), which closes the fd, hence has to acquire an exclusive lock.
-	fdLock sync.RWMutex
-
-	// Was the file opened O_WRONLY?
-	writeOnly bool
-
-	// Content encryption helper
-	contentEnc *contentenc.ContentEnc
-
-	// Inode number
-	ino uint64
-
-	// File header
-	header *contentenc.FileHeader
-
-	forgotten bool
-}
-
-func NewFile(fd *os.File, writeOnly bool, contentEnc *contentenc.ContentEnc) nodefs.File {
-	var st syscall.Stat_t
-	syscall.Fstat(int(fd.Fd()), &st)
-	wlock.register(st.Ino)
-
-	return &file{
-		fd:        fd,
-		writeOnly: writeOnly,
-		contentEnc: contentEnc,
-		ino:       st.Ino,
-	}
-}
-
-// intFd - return the backing file descriptor as an integer. Used for debug
-// messages.
-func (f *file) intFd() int {
-	return int(f.fd.Fd())
-}
-
-func (f *file) InnerFile() nodefs.File {
-	return nil
-}
-
-func (f *file) SetInode(n *nodefs.Inode) {
-}
-
-// readHeader - load the file header from disk
-//
-// Returns io.EOF if the file is empty
-func (f *file) readHeader() error {
-	buf := make([]byte, contentenc.HEADER_LEN)
-	_, err := f.fd.ReadAt(buf, 0)
-	if err != nil {
-		return err
-	}
-	h, err := contentenc.ParseHeader(buf)
-	if err != nil {
-		return err
-	}
-	f.header = h
-
-	return nil
-}
-
-// createHeader - create a new random header and write it to disk
-func (f *file) createHeader() error {
-	h := contentenc.RandomHeader()
-	buf := h.Pack()
-
-	// Prevent partially written (=corrupt) header by preallocating the space beforehand
-	err := prealloc(int(f.fd.Fd()), 0, contentenc.HEADER_LEN)
-	if err != nil {
-		toggledlog.Warn.Printf("ino%d: createHeader: prealloc failed: %s\n", f.ino, err.Error())
-		return err
-	}
-
-	// Actually write header
-	_, err = f.fd.WriteAt(buf, 0)
-	if err != nil {
-		return err
-	}
-	f.header = h
-
-	return nil
-}
-
-func (f *file) String() string {
-	return fmt.Sprintf("cryptFile(%s)", f.fd.Name())
-}
-
-// doRead - returns "length" plaintext bytes from plaintext offset "off".
-// Arguments "length" and "off" do not have to be block-aligned.
-//
-// doRead reads the corresponding ciphertext blocks from disk, decrypts them and
-// returns the requested part of the plaintext.
-//
-// Called by Read() for normal reading,
-// by Write() and Truncate() for Read-Modify-Write
-func (f *file) doRead(off uint64, length uint64) ([]byte, fuse.Status) {
-
-	// Read file header
-	if f.header == nil {
-		err := f.readHeader()
-		if err == io.EOF {
-			return nil, fuse.OK
-		}
-		if err != nil {
-			return nil, fuse.ToStatus(err)
-		}
-	}
-
-	// Read the backing ciphertext in one go
-	blocks := f.contentEnc.ExplodePlainRange(off, length)
-	alignedOffset, alignedLength := blocks[0].JointCiphertextRange(blocks)
-	skip := blocks[0].Skip
-	toggledlog.Debug.Printf("JointCiphertextRange(%d, %d) -> %d, %d, %d", off, length, alignedOffset, alignedLength, skip)
-	ciphertext := make([]byte, int(alignedLength))
-	n, err := f.fd.ReadAt(ciphertext, int64(alignedOffset))
-	if err != nil && err != io.EOF {
-		toggledlog.Warn.Printf("read: ReadAt: %s", err.Error())
-		return nil, fuse.ToStatus(err)
-	}
-	// Truncate ciphertext buffer down to actually read bytes
-	ciphertext = ciphertext[0:n]
-
-	firstBlockNo := blocks[0].BlockNo
-	toggledlog.Debug.Printf("ReadAt offset=%d bytes (%d blocks), want=%d, got=%d", alignedOffset, firstBlockNo, alignedLength, n)
-
-	// Decrypt it
-	plaintext, err := f.contentEnc.DecryptBlocks(ciphertext, firstBlockNo, f.header.Id)
-	if err != nil {
-		curruptBlockNo := firstBlockNo + f.contentEnc.PlainOffToBlockNo(uint64(len(plaintext)))
-		cipherOff := f.contentEnc.BlockNoToCipherOff(curruptBlockNo)
-		plainOff := f.contentEnc.BlockNoToPlainOff(curruptBlockNo)
-		toggledlog.Warn.Printf("ino%d: doRead: corrupt block #%d (plainOff=%d, cipherOff=%d)",
-			f.ino, curruptBlockNo, plainOff, cipherOff)
-		return nil, fuse.EIO
-	}
-
-	// Crop down to the relevant part
-	var out []byte
-	lenHave := len(plaintext)
-	lenWant := int(skip + length)
-	if lenHave > lenWant {
-		out = plaintext[skip:lenWant]
-	} else if lenHave > int(skip) {
-		out = plaintext[skip:lenHave]
-	}
-	// else: out stays empty, file was smaller than the requested offset
-
-	return out, fuse.OK
-}
-
-// Read - FUSE call
-func (f *file) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fuse.Status) {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	toggledlog.Debug.Printf("ino%d: FUSE Read: offset=%d length=%d", f.ino, len(buf), off)
-
-	if f.writeOnly {
-		toggledlog.Warn.Printf("ino%d: Tried to read from write-only file", f.ino)
-		return nil, fuse.EBADF
-	}
-
-	out, status := f.doRead(uint64(off), uint64(len(buf)))
-
-	if status == fuse.EIO {
-		toggledlog.Warn.Printf("ino%d: Read failed with EIO, offset=%d, length=%d", f.ino, len(buf), off)
-	}
-	if status != fuse.OK {
-		return nil, status
-	}
-
-	toggledlog.Debug.Printf("ino%d: Read: status %v, returning %d bytes", f.ino, status, len(out))
-	return fuse.ReadResultData(out), status
-}
-
-const FALLOC_FL_KEEP_SIZE = 0x01
-
-// doWrite - encrypt "data" and write it to plaintext offset "off"
-//
-// Arguments do not have to be block-aligned, read-modify-write is
-// performed internally as neccessary
-//
-// Called by Write() for normal writing,
-// and by Truncate() to rewrite the last file block.
-func (f *file) doWrite(data []byte, off int64) (uint32, fuse.Status) {
-
-	// Read header from disk, create a new one if the file is empty
-	if f.header == nil {
-		err := f.readHeader()
-		if err == io.EOF {
-			err = f.createHeader()
-
-		}
-		if err != nil {
-			return 0, fuse.ToStatus(err)
-		}
-	}
-
-	var written uint32
-	status := fuse.OK
-	dataBuf := bytes.NewBuffer(data)
-	blocks := f.contentEnc.ExplodePlainRange(uint64(off), uint64(len(data)))
-	for _, b := range blocks {
-
-		blockData := dataBuf.Next(int(b.Length))
-
-		// Incomplete block -> Read-Modify-Write
-		if b.IsPartial() {
-			// Read
-			o, _ := b.PlaintextRange()
-			oldData, status := f.doRead(o, f.contentEnc.PlainBS())
-			if status != fuse.OK {
-				toggledlog.Warn.Printf("ino%d fh%d: RMW read failed: %s", f.ino, f.intFd(), status.String())
-				return written, status
-			}
-			// Modify
-			blockData = f.contentEnc.MergeBlocks(oldData, blockData, int(b.Skip))
-			toggledlog.Debug.Printf("len(oldData)=%d len(blockData)=%d", len(oldData), len(blockData))
-		}
-
-		// Encrypt
-		blockOffset, blockLen := b.CiphertextRange()
-		blockData = f.contentEnc.EncryptBlock(blockData, b.BlockNo, f.header.Id)
-		toggledlog.Debug.Printf("ino%d: Writing %d bytes to block #%d",
-			f.ino, uint64(len(blockData))-f.contentEnc.BlockOverhead(), b.BlockNo)
-
-		// Prevent partially written (=corrupt) blocks by preallocating the space beforehand
-		err := prealloc(int(f.fd.Fd()), int64(blockOffset), int64(blockLen))
-		if err != nil {
-			toggledlog.Warn.Printf("ino%d fh%d: doWrite: prealloc failed: %s", f.ino, f.intFd(), err.Error())
-			status = fuse.ToStatus(err)
-			break
-		}
-
-		// Write
-		_, err = f.fd.WriteAt(blockData, int64(blockOffset))
-
-		if err != nil {
-			toggledlog.Warn.Printf("doWrite: Write failed: %s", err.Error())
-			status = fuse.ToStatus(err)
-			break
-		}
-		written += uint32(b.Length)
-	}
-	return written, status
-}
-
-// Write - FUSE call
-func (f *file) Write(data []byte, off int64) (uint32, fuse.Status) {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-	wlock.lock(f.ino)
-	defer wlock.unlock(f.ino)
-
-	toggledlog.Debug.Printf("ino%d: FUSE Write: offset=%d length=%d", f.ino, off, len(data))
-
-	fi, err := f.fd.Stat()
-	if err != nil {
-		toggledlog.Warn.Printf("Write: Fstat failed: %v", err)
-		return 0, fuse.ToStatus(err)
-	}
-	plainSize := f.contentEnc.CipherSizeToPlainSize(uint64(fi.Size()))
-	if f.createsHole(plainSize, off) {
-		status := f.zeroPad(plainSize)
-		if status != fuse.OK {
-			toggledlog.Warn.Printf("zeroPad returned error %v", status)
-			return 0, status
-		}
-	}
-	return f.doWrite(data, off)
-}
-
-// Release - FUSE call, close file
-func (f *file) Release() {
-	f.fdLock.Lock()
-	defer f.fdLock.Unlock()
-
-	f.fd.Close()
-	f.forgotten = true
-}
-
-// Flush - FUSE call
-func (f *file) Flush() fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	// Since Flush() may be called for each dup'd fd, we don't
-	// want to really close the file, we just want to flush. This
-	// is achieved by closing a dup'd fd.
-	newFd, err := syscall.Dup(int(f.fd.Fd()))
-
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	err = syscall.Close(newFd)
-	return fuse.ToStatus(err)
-}
-
-func (f *file) Fsync(flags int) (code fuse.Status) {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	return fuse.ToStatus(syscall.Fsync(int(f.fd.Fd())))
-}
-
-// Truncate - FUSE call
-func (f *file) Truncate(newSize uint64) fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-	wlock.lock(f.ino)
-	defer wlock.unlock(f.ino)
-
-	if f.forgotten {
-		toggledlog.Warn.Printf("ino%d fh%d: Truncate on forgotten file", f.ino, f.intFd())
-	}
-
-	// Common case first: Truncate to zero
-	if newSize == 0 {
-		err := syscall.Ftruncate(int(f.fd.Fd()), 0)
-		if err != nil {
-			toggledlog.Warn.Printf("ino%d fh%d: Ftruncate(fd, 0) returned error: %v", f.ino, f.intFd(), err)
-			return fuse.ToStatus(err)
-		}
-		// Truncate to zero kills the file header
-		f.header = nil
-		return fuse.OK
-	}
-
-	// We need the old file size to determine if we are growing or shrinking
-	// the file
-	fi, err := f.fd.Stat()
-	if err != nil {
-		toggledlog.Warn.Printf("ino%d fh%d: Truncate: Fstat failed: %v", f.ino, f.intFd(), err)
-		return fuse.ToStatus(err)
-	}
-	oldSize := f.contentEnc.CipherSizeToPlainSize(uint64(fi.Size()))
-	{
-		oldB := float32(oldSize) / float32(f.contentEnc.PlainBS())
-		newB := float32(newSize) / float32(f.contentEnc.PlainBS())
-		toggledlog.Debug.Printf("ino%d: FUSE Truncate from %.2f to %.2f blocks (%d to %d bytes)", f.ino, oldB, newB, oldSize, newSize)
-	}
-
-	// File size stays the same - nothing to do
-	if newSize == oldSize {
-		return fuse.OK
-	}
-
-	// File grows
-	if newSize > oldSize {
-
-		// File was empty, create new header
-		if oldSize == 0 {
-			err := f.createHeader()
-			if err != nil {
-				return fuse.ToStatus(err)
-			}
-		}
-
-		blocks := f.contentEnc.ExplodePlainRange(oldSize, newSize-oldSize)
-		for _, b := range blocks {
-			// First and last block may be partial
-			if b.IsPartial() {
-				off, _ := b.PlaintextRange()
-				off += b.Skip
-				_, status := f.doWrite(make([]byte, b.Length), int64(off))
-				if status != fuse.OK {
-					return status
-				}
-			} else {
-				off, length := b.CiphertextRange()
-				err := syscall.Ftruncate(int(f.fd.Fd()), int64(off+length))
-				if err != nil {
-					toggledlog.Warn.Printf("grow Ftruncate returned error: %v", err)
-					return fuse.ToStatus(err)
-				}
-			}
-		}
-		return fuse.OK
-	} else {
-		// File shrinks
-		blockNo := f.contentEnc.PlainOffToBlockNo(newSize)
-		cipherOff := f.contentEnc.BlockNoToCipherOff(blockNo)
-		plainOff := f.contentEnc.BlockNoToPlainOff(blockNo)
-		lastBlockLen := newSize - plainOff
-		var data []byte
-		if lastBlockLen > 0 {
-			var status fuse.Status
-			data, status = f.doRead(plainOff, lastBlockLen)
-			if status != fuse.OK {
-				toggledlog.Warn.Printf("shrink doRead returned error: %v", err)
-				return status
-			}
-		}
-		// Truncate down to last complete block
-		err = syscall.Ftruncate(int(f.fd.Fd()), int64(cipherOff))
-		if err != nil {
-			toggledlog.Warn.Printf("shrink Ftruncate returned error: %v", err)
-			return fuse.ToStatus(err)
-		}
-		// Append partial block
-		if lastBlockLen > 0 {
-			_, status := f.doWrite(data, int64(plainOff))
-			return status
-		}
-		return fuse.OK
-	}
-}
-
-func (f *file) Chmod(mode uint32) fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	return fuse.ToStatus(f.fd.Chmod(os.FileMode(mode)))
-}
-
-func (f *file) Chown(uid uint32, gid uint32) fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	return fuse.ToStatus(f.fd.Chown(int(uid), int(gid)))
-}
-
-func (f *file) GetAttr(a *fuse.Attr) fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	toggledlog.Debug.Printf("file.GetAttr()")
-	st := syscall.Stat_t{}
-	err := syscall.Fstat(int(f.fd.Fd()), &st)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	a.FromStat(&st)
-	a.Size = f.contentEnc.CipherSizeToPlainSize(a.Size)
-
-	return fuse.OK
-}
-
-// Allocate - FUSE call, fallocate(2)
-var allocateWarned bool
-
-func (f *file) Allocate(off uint64, sz uint64, mode uint32) fuse.Status {
-	// Only warn once
-	if !allocateWarned {
-		toggledlog.Warn.Printf("fallocate(2) is not supported, returning ENOSYS - see https://github.com/rfjakob/gocryptfs/issues/1")
-		allocateWarned = true
-	}
-	return fuse.ENOSYS
-}
-
-const _UTIME_OMIT = ((1 << 30) - 2)
-
-func (f *file) Utimens(a *time.Time, m *time.Time) fuse.Status {
-	f.fdLock.RLock()
-	defer f.fdLock.RUnlock()
-
-	ts := make([]syscall.Timespec, 2)
-
-	if a == nil {
-		ts[0].Nsec = _UTIME_OMIT
-	} else {
-		ts[0].Sec = a.Unix()
-	}
-
-	if m == nil {
-		ts[1].Nsec = _UTIME_OMIT
-	} else {
-		ts[1].Sec = m.Unix()
-	}
-
-	fn := fmt.Sprintf("/proc/self/fd/%d", f.fd.Fd())
-	return fuse.ToStatus(syscall.UtimesNano(fn, ts))
-}
diff --git a/pathfs_frontend/file_holes.go b/pathfs_frontend/file_holes.go
deleted file mode 100644
index a147deb..0000000
--- a/pathfs_frontend/file_holes.go
+++ /dev/null
@@ -1,29 +0,0 @@
-package pathfs_frontend
-
-// Helper functions for sparse files (files with holes)
-
-import (
-	"github.com/hanwen/go-fuse/fuse"
-
-	"github.com/rfjakob/gocryptfs/internal/toggledlog"
-)
-
-// Will a write to offset "off" create a file hole?
-func (f *file) createsHole(plainSize uint64, off int64) bool {
-	nextBlock := f.contentEnc.PlainOffToBlockNo(plainSize)
-	targetBlock := f.contentEnc.PlainOffToBlockNo(uint64(off))
-	if targetBlock > nextBlock {
-		return true
-	}
-	return false
-}
-
-// Zero-pad the file of size plainSize to the next block boundary
-func (f *file) zeroPad(plainSize uint64) fuse.Status {
-	lastBlockLen := plainSize % f.contentEnc.PlainBS()
-	missing := f.contentEnc.PlainBS() - lastBlockLen
-	pad := make([]byte, missing)
-	toggledlog.Debug.Printf("zeroPad: Writing %d bytes\n", missing)
-	_, status := f.doWrite(pad, int64(plainSize))
-	return status
-}
diff --git a/pathfs_frontend/fs.go b/pathfs_frontend/fs.go
deleted file mode 100644
index 212f0a7..0000000
--- a/pathfs_frontend/fs.go
+++ /dev/null
@@ -1,381 +0,0 @@
-package pathfs_frontend
-
-// FUSE operations on paths
-
-import (
-	"encoding/base64"
-	"os"
-	"path/filepath"
-	"sync"
-	"syscall"
-	"time"
-
-	"github.com/hanwen/go-fuse/fuse"
-	"github.com/hanwen/go-fuse/fuse/nodefs"
-	"github.com/hanwen/go-fuse/fuse/pathfs"
-
-	"github.com/rfjakob/gocryptfs/internal/toggledlog"
-	"github.com/rfjakob/gocryptfs/internal/cryptocore"
-	"github.com/rfjakob/gocryptfs/internal/nametransform"
-	"github.com/rfjakob/gocryptfs/internal/contentenc"
-	"github.com/rfjakob/gocryptfs/internal/configfile"
-)
-
-const plainBS = 4096
-
-type FS struct {
-	pathfs.FileSystem      // loopbackFileSystem, see go-fuse/fuse/pathfs/loopback.go
-	args              Args // Stores configuration arguments
-	// dirIVLock: Lock()ed if any "gocryptfs.diriv" file is modified
-	// Readers must RLock() it to prevent them from seeing intermediate
-	// states
-	dirIVLock sync.RWMutex
-	// Filename encryption helper
-	nameTransform *nametransform.NameTransform
-	// Content encryption helper
-	contentEnc *contentenc.ContentEnc
-}
-
-// Encrypted FUSE overlay filesystem
-func NewFS(args Args) *FS {
-
-	cryptoCore := cryptocore.New(args.Masterkey, args.OpenSSL, args.GCMIV128)
-	contentEnc := contentenc.New(cryptoCore, plainBS)
-	nameTransform := nametransform.New(cryptoCore, args.EMENames)
-
-	return &FS{
-		FileSystem: pathfs.NewLoopbackFileSystem(args.Cipherdir),
-		args:       args,
-		nameTransform: nameTransform,
-		contentEnc: contentEnc,
-	}
-}
-
-// GetBackingPath - get the absolute encrypted path of the backing file
-// from the relative plaintext path "relPath"
-func (fs *FS) getBackingPath(relPath string) (string, error) {
-	cPath, err := fs.encryptPath(relPath)
-	if err != nil {
-		return "", err
-	}
-	cAbsPath := filepath.Join(fs.args.Cipherdir, cPath)
-	toggledlog.Debug.Printf("getBackingPath: %s + %s -> %s", fs.args.Cipherdir, relPath, cAbsPath)
-	return cAbsPath, nil
-}
-
-func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
-	toggledlog.Debug.Printf("FS.GetAttr('%s')", name)
-	if fs.isFiltered(name) {
-		return nil, fuse.EPERM
-	}
-	cName, err := fs.encryptPath(name)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	a, status := fs.FileSystem.GetAttr(cName, context)
-	if a == nil {
-		toggledlog.Debug.Printf("FS.GetAttr failed: %s", status.String())
-		return a, status
-	}
-	if a.IsRegular() {
-		a.Size = fs.contentEnc.CipherSizeToPlainSize(a.Size)
-	} else if a.IsSymlink() {
-		target, _ := fs.Readlink(name, context)
-		a.Size = uint64(len(target))
-	}
-	return a, status
-}
-
-func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, fuse.Status) {
-	toggledlog.Debug.Printf("OpenDir(%s)", dirName)
-	cDirName, err := fs.encryptPath(dirName)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	// Read ciphertext directory
-	cipherEntries, status := fs.FileSystem.OpenDir(cDirName, context)
-	if cipherEntries == nil {
-		return nil, status
-	}
-	// Get DirIV (stays nil if DirIV if off)
-	var cachedIV []byte
-	if fs.args.DirIV {
-		// Read the DirIV once and use it for all later name decryptions
-		cDirAbsPath := filepath.Join(fs.args.Cipherdir, cDirName)
-		cachedIV, err = fs.nameTransform.ReadDirIV(cDirAbsPath)
-		if err != nil {
-			return nil, fuse.ToStatus(err)
-		}
-	}
-	// Filter and decrypt filenames
-	var plain []fuse.DirEntry
-	for i := range cipherEntries {
-		cName := cipherEntries[i].Name
-		if dirName == "" && cName == configfile.ConfDefaultName {
-			// silently ignore "gocryptfs.conf" in the top level dir
-			continue
-		}
-		if fs.args.DirIV && cName == nametransform.DirIVFilename {
-			// silently ignore "gocryptfs.diriv" everywhere if dirIV is enabled
-			continue
-		}
-		var name string = cName
-		if !fs.args.PlaintextNames {
-			name, err = fs.nameTransform.DecryptName(cName, cachedIV)
-			if err != nil {
-				toggledlog.Warn.Printf("Invalid name \"%s\" in dir \"%s\": %s", cName, cDirName, err)
-				continue
-			}
-		}
-		cipherEntries[i].Name = name
-		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(path string, flags uint32, context *fuse.Context) (fuseFile nodefs.File, status fuse.Status) {
-	if fs.isFiltered(path) {
-		return nil, fuse.EPERM
-	}
-	iflags, writeOnly := fs.mangleOpenFlags(flags)
-	cPath, err := fs.getBackingPath(path)
-	if err != nil {
-		toggledlog.Debug.Printf("Open: getBackingPath: %v", err)
-		return nil, fuse.ToStatus(err)
-	}
-	toggledlog.Debug.Printf("Open: %s", cPath)
-	f, err := os.OpenFile(cPath, iflags, 0666)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-
-	return NewFile(f, writeOnly, fs.contentEnc), fuse.OK
-}
-
-func (fs *FS) Create(path string, flags uint32, mode uint32, context *fuse.Context) (fuseFile nodefs.File, code fuse.Status) {
-	if fs.isFiltered(path) {
-		return nil, fuse.EPERM
-	}
-	iflags, writeOnly := fs.mangleOpenFlags(flags)
-	cPath, err := fs.getBackingPath(path)
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	f, err := os.OpenFile(cPath, iflags|os.O_CREATE, os.FileMode(mode))
-	if err != nil {
-		return nil, fuse.ToStatus(err)
-	}
-	return NewFile(f, writeOnly, fs.contentEnc), fuse.OK
-}
-
-func (fs *FS) Chmod(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.encryptPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fs.FileSystem.Chmod(cPath, mode, context)
-}
-
-func (fs *FS) Chown(path string, uid uint32, gid uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.encryptPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fs.FileSystem.Chown(cPath, uid, gid, context)
-}
-
-func (fs *FS) Mknod(path string, mode uint32, dev uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.encryptPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fs.FileSystem.Mknod(cPath, mode, dev, context)
-}
-
-var truncateWarned bool
-
-func (fs *FS) Truncate(path string, offset uint64, context *fuse.Context) (code fuse.Status) {
-	// Only warn once
-	if !truncateWarned {
-		toggledlog.Warn.Printf("truncate(2) is not supported, returning ENOSYS - use ftruncate(2)")
-		truncateWarned = true
-	}
-	return fuse.ENOSYS
-}
-
-func (fs *FS) Utimens(path string, Atime *time.Time, Mtime *time.Time, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.encryptPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fs.FileSystem.Utimens(cPath, Atime, Mtime, context)
-}
-
-func (fs *FS) Readlink(path string, context *fuse.Context) (out string, status fuse.Status) {
-	cPath, err := fs.encryptPath(path)
-	if err != nil {
-		return "", fuse.ToStatus(err)
-	}
-	cTarget, status := fs.FileSystem.Readlink(cPath, context)
-	if status != fuse.OK {
-		return "", status
-	}
-	// Old filesystem: symlinks are encrypted like paths (CBC)
-	if !fs.args.DirIV {
-		target, err := fs.decryptPath(cTarget)
-		if err != nil {
-			toggledlog.Warn.Printf("Readlink: CBC decryption failed: %v", err)
-			return "", fuse.EIO
-		}
-		return target, fuse.OK
-	}
-	// Since gocryptfs v0.5 symlinks are encrypted like file contents (GCM)
-	cBinTarget, err := base64.URLEncoding.DecodeString(cTarget)
-	if err != nil {
-		toggledlog.Warn.Printf("Readlink: %v", err)
-		return "", fuse.EIO
-	}
-	target, err := fs.contentEnc.DecryptBlock([]byte(cBinTarget), 0, nil)
-	if err != nil {
-		toggledlog.Warn.Printf("Readlink: %v", err)
-		return "", fuse.EIO
-	}
-	return string(target), fuse.OK
-}
-
-func (fs *FS) Unlink(path string, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.getBackingPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fuse.ToStatus(syscall.Unlink(cPath))
-}
-
-func (fs *FS) Symlink(target string, linkName string, context *fuse.Context) (code fuse.Status) {
-	toggledlog.Debug.Printf("Symlink(\"%s\", \"%s\")", target, linkName)
-	if fs.isFiltered(linkName) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.getBackingPath(linkName)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	// Old filesystem: symlinks are encrypted like paths (CBC)
-	if !fs.args.DirIV {
-		cTarget, err := fs.encryptPath(target)
-		if err != nil {
-			toggledlog.Warn.Printf("Symlink: BUG: we should not get an error here: %v", err)
-			return fuse.ToStatus(err)
-		}
-		err = os.Symlink(cTarget, cPath)
-		return fuse.ToStatus(err)
-	}
-	// Since gocryptfs v0.5 symlinks are encrypted like file contents (GCM)
-	cBinTarget := fs.contentEnc.EncryptBlock([]byte(target), 0, nil)
-	cTarget := base64.URLEncoding.EncodeToString(cBinTarget)
-
-	err = os.Symlink(cTarget, cPath)
-	toggledlog.Debug.Printf("Symlink: os.Symlink(%s, %s) = %v", cTarget, cPath, err)
-	return fuse.ToStatus(err)
-}
-
-func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(newPath) {
-		return fuse.EPERM
-	}
-	cOldPath, err := fs.getBackingPath(oldPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	cNewPath, err := fs.getBackingPath(newPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	// The Rename may cause a directory to take the place of another directory.
-	// That directory may still be in the DirIV cache, clear it.
-	fs.nameTransform.DirIVCache.Clear()
-
-	err = os.Rename(cOldPath, cNewPath)
-
-	if lerr, ok := err.(*os.LinkError); ok && lerr.Err == syscall.ENOTEMPTY {
-		// If an empty directory is overwritten we will always get
-		// ENOTEMPTY as the "empty" directory will still contain gocryptfs.diriv.
-		// Handle that case by removing the target directory and trying again.
-		toggledlog.Debug.Printf("Rename: Handling ENOTEMPTY")
-		if fs.Rmdir(newPath, context) == fuse.OK {
-			err = os.Rename(cOldPath, cNewPath)
-		}
-	}
-
-	return fuse.ToStatus(err)
-}
-
-func (fs *FS) Link(oldPath string, newPath string, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(newPath) {
-		return fuse.EPERM
-	}
-	cOldPath, err := fs.getBackingPath(oldPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	cNewPath, err := fs.getBackingPath(newPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fuse.ToStatus(os.Link(cOldPath, cNewPath))
-}
-
-func (fs *FS) Access(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(path) {
-		return fuse.EPERM
-	}
-	cPath, err := fs.getBackingPath(path)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	return fuse.ToStatus(syscall.Access(cPath, mode))
-}
-
-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
-}
diff --git a/pathfs_frontend/fs_dir.go b/pathfs_frontend/fs_dir.go
deleted file mode 100644
index d378d28..0000000
--- a/pathfs_frontend/fs_dir.go
+++ /dev/null
@@ -1,157 +0,0 @@
-package pathfs_frontend
-
-// Mkdir and Rmdir
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"syscall"
-
-	"github.com/hanwen/go-fuse/fuse"
-
-	"github.com/rfjakob/gocryptfs/internal/toggledlog"
-	"github.com/rfjakob/gocryptfs/internal/cryptocore"
-	"github.com/rfjakob/gocryptfs/internal/nametransform"
-)
-
-func (fs *FS) Mkdir(relPath string, mode uint32, context *fuse.Context) (code fuse.Status) {
-	if fs.isFiltered(relPath) {
-		return fuse.EPERM
-	}
-	encPath, err := fs.getBackingPath(relPath)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	if !fs.args.DirIV {
-		return fuse.ToStatus(os.Mkdir(encPath, os.FileMode(mode)))
-	}
-
-	// We need write and execute permissions to create gocryptfs.diriv
-	origMode := mode
-	mode = mode | 0300
-
-	// The new directory may take the place of an older one that is still in the cache
-	fs.nameTransform.DirIVCache.Clear()
-	// Create directory
-	fs.dirIVLock.Lock()
-	defer fs.dirIVLock.Unlock()
-	err = os.Mkdir(encPath, os.FileMode(mode))
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	// Create gocryptfs.diriv inside
-	err = nametransform.WriteDirIV(encPath)
-	if err != nil {
-		// This should not happen
-		toggledlog.Warn.Printf("Mkdir: WriteDirIV failed: %v", err)
-		err2 := syscall.Rmdir(encPath)
-		if err2 != nil {
-			toggledlog.Warn.Printf("Mkdir: Rmdir rollback failed: %v", err2)
-		}
-		return fuse.ToStatus(err)
-	}
-
-	// Set permissions back to what the user wanted
-	if origMode != mode {
-		err = os.Chmod(encPath, os.FileMode(origMode))
-		if err != nil {
-			toggledlog.Warn.Printf("Mkdir: Chmod failed: %v", err)
-		}
-	}
-
-	return fuse.OK
-}
-
-func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
-	encPath, err := fs.getBackingPath(name)
-	if err != nil {
-		return fuse.ToStatus(err)
-	}
-	if !fs.args.DirIV {
-		return fuse.ToStatus(syscall.Rmdir(encPath))
-	}
-
-	// If the directory is not empty besides gocryptfs.diriv, do not even
-	// attempt the dance around gocryptfs.diriv.
-	fd, err := os.Open(encPath)
-	if perr, ok := err.(*os.PathError); ok && perr.Err == syscall.EACCES {
-		// We need permission to read and modify the directory
-		toggledlog.Debug.Printf("Rmdir: handling EACCESS")
-		fi, err2 := os.Stat(encPath)
-		if err2 != nil {
-			toggledlog.Debug.Printf("Rmdir: Stat: %v", err2)
-			return fuse.ToStatus(err2)
-		}
-		origMode := fi.Mode()
-		newMode := origMode | 0700
-		err2 = os.Chmod(encPath, newMode)
-		if err2 != nil {
-			toggledlog.Debug.Printf("Rmdir: Chmod failed: %v", err2)
-			return fuse.ToStatus(err)
-		}
-		defer func() {
-			if code != fuse.OK {
-				// Undo the chmod if removing the directory failed
-				err3 := os.Chmod(encPath, origMode)
-				if err3 != nil {
-					toggledlog.Warn.Printf("Rmdir: Chmod rollback failed: %v", err2)
-				}
-			}
-		}()
-		// Retry open
-		fd, err = os.Open(encPath)
-	}
-	if err != nil {
-		toggledlog.Debug.Printf("Rmdir: Open: %v", err)
-		return fuse.ToStatus(err)
-	}
-	list, err := fd.Readdirnames(10)
-	fd.Close()
-	if err != nil {
-		toggledlog.Debug.Printf("Rmdir: Readdirnames: %v", err)
-		return fuse.ToStatus(err)
-	}
-	if len(list) > 1 {
-		return fuse.ToStatus(syscall.ENOTEMPTY)
-	} else if len(list) == 0 {
-		toggledlog.Warn.Printf("Rmdir: gocryptfs.diriv missing, allowing deletion")
-		return fuse.ToStatus(syscall.Rmdir(encPath))
-	}
-
-	// Move "gocryptfs.diriv" to the parent dir as "gocryptfs.diriv.rmdir.XYZ"
-	dirivPath := filepath.Join(encPath, nametransform.DirIVFilename)
-	parentDir := filepath.Dir(encPath)
-	tmpName := fmt.Sprintf("gocryptfs.diriv.rmdir.%d", cryptocore.RandUint64())
-	tmpDirivPath := filepath.Join(parentDir, tmpName)
-	toggledlog.Debug.Printf("Rmdir: Renaming %s to %s", nametransform.DirIVFilename, tmpDirivPath)
-	// The directory is in an inconsistent state between rename and rmdir. Protect against
-	// concurrent readers.
-	fs.dirIVLock.Lock()
-	defer fs.dirIVLock.Unlock()
-	err = os.Rename(dirivPath, tmpDirivPath)
-	if err != nil {
-		toggledlog.Warn.Printf("Rmdir: Renaming %s to %s failed: %v",
-			nametransform.DirIVFilename, tmpDirivPath, err)
-		return fuse.ToStatus(err)
-	}
-	// Actual Rmdir
-	err = syscall.Rmdir(encPath)
-	if err != nil {
-		// This can happen if another file in the directory was created in the
-		// meantime, undo the rename
-		err2 := os.Rename(tmpDirivPath, dirivPath)
-		if err2 != nil {
-			toggledlog.Warn.Printf("Rmdir: Rename rollback failed: %v", err2)
-		}
-		return fuse.ToStatus(err)
-	}
-	// Delete "gocryptfs.diriv.rmdir.INODENUMBER"
-	err = syscall.Unlink(tmpDirivPath)
-	if err != nil {
-		toggledlog.Warn.Printf("Rmdir: Could not clean up %s: %v", tmpName, err)
-	}
-	// The now-deleted directory may have been in the DirIV cache. Clear it.
-	fs.nameTransform.DirIVCache.Clear()
-	return fuse.OK
-}
diff --git a/pathfs_frontend/names.go b/pathfs_frontend/names.go
deleted file mode 100644
index 160fa0a..0000000
--- a/pathfs_frontend/names.go
+++ /dev/null
@@ -1,52 +0,0 @@
-package pathfs_frontend
-
-// This file forwards file encryption operations to cryptfs
-
-import (
-	"github.com/rfjakob/gocryptfs/internal/configfile"
-	mylog "github.com/rfjakob/gocryptfs/internal/toggledlog"
-)
-
-// isFiltered - check if plaintext "path" should be forbidden
-//
-// Prevents name clashes with internal files when file names are not encrypted
-func (fs *FS) isFiltered(path string) bool {
-	if !fs.args.PlaintextNames {
-		return false
-	}
-	// gocryptfs.conf in the root directory is forbidden
-	if path == configfile.ConfDefaultName {
-		mylog.Info.Printf("The name /%s is reserved when -plaintextnames is used\n",
-			configfile.ConfDefaultName)
-		return true
-	}
-	// Note: gocryptfs.diriv is NOT forbidden because diriv and plaintextnames
-	// are exclusive
-	return false
-}
-
-// encryptPath - encrypt relative plaintext path
-func (fs *FS) encryptPath(plainPath string) (string, error) {
-	if fs.args.PlaintextNames {
-		return plainPath, nil
-	}
-	if !fs.args.DirIV {
-		return fs.nameTransform.EncryptPathNoIV(plainPath), nil
-	}
-	fs.dirIVLock.RLock()
-	defer fs.dirIVLock.RUnlock()
-	return fs.nameTransform.EncryptPathDirIV(plainPath, fs.args.Cipherdir)
-}
-
-// decryptPath - decrypt relative ciphertext path
-func (fs *FS) decryptPath(cipherPath string) (string, error) {
-	if fs.args.PlaintextNames {
-		return cipherPath, nil
-	}
-	if !fs.args.DirIV {
-		return fs.nameTransform.DecryptPathNoIV(cipherPath)
-	}
-	fs.dirIVLock.RLock()
-	defer fs.dirIVLock.RUnlock()
-	return fs.nameTransform.DecryptPathDirIV(cipherPath, fs.args.Cipherdir, fs.args.EMENames)
-}
diff --git a/pathfs_frontend/write_lock.go b/pathfs_frontend/write_lock.go
deleted file mode 100644
index 0704eb6..0000000
--- a/pathfs_frontend/write_lock.go
+++ /dev/null
@@ -1,66 +0,0 @@
-package pathfs_frontend
-
-import (
-	"sync"
-)
-
-func init() {
-	wlock.m = make(map[uint64]*refCntMutex)
-}
-
-// wlock - serializes write accesses to each file (identified by inode number)
-// Writing partial blocks means we have to do read-modify-write cycles. We
-// really don't want concurrent writes there.
-// Concurrent full-block writes could actually be allowed, but are not to
-// keep the locking simple.
-var wlock wlockMap
-
-// wlockMap - usage:
-// 1) register
-// 2) lock ... unlock ...
-// 3) unregister
-type wlockMap struct {
-	mapMutex sync.RWMutex
-	m        map[uint64]*refCntMutex
-}
-
-func (w *wlockMap) register(ino uint64) {
-	w.mapMutex.Lock()
-	r := w.m[ino]
-	if r == nil {
-		r = &refCntMutex{}
-		w.m[ino] = r
-	}
-	r.refCnt++ // this must happen inside the mapMutex lock
-	w.mapMutex.Unlock()
-}
-
-func (w *wlockMap) unregister(ino uint64) {
-	w.mapMutex.Lock()
-	r := w.m[ino]
-	r.refCnt--
-	if r.refCnt == 0 {
-		delete(w.m, ino)
-	}
-	w.mapMutex.Unlock()
-}
-
-func (w *wlockMap) lock(ino uint64) {
-	w.mapMutex.RLock()
-	r := w.m[ino]
-	w.mapMutex.RUnlock()
-	r.Lock() // this can take a long time - execute outside the mapMutex lock
-}
-
-func (w *wlockMap) unlock(ino uint64) {
-	w.mapMutex.RLock()
-	r := w.m[ino]
-	w.mapMutex.RUnlock()
-	r.Unlock()
-}
-
-// refCntMutex - mutex with reference count
-type refCntMutex struct {
-	sync.Mutex
-	refCnt int
-}