Major refactoring: Split up "cryptfs" into several internal packages

"git status" for reference:

deleted:    cryptfs/cryptfs.go
deleted:    cryptfs/names_core.go
modified:   integration_tests/cli_test.go
modified:   integration_tests/helpers.go
renamed:    cryptfs/config_file.go -> internal/configfile/config_file.go
renamed:    cryptfs/config_test.go -> internal/configfile/config_test.go
renamed:    cryptfs/config_test/.gitignore -> internal/configfile/config_test/.gitignore
renamed:    cryptfs/config_test/PlaintextNames.conf -> internal/configfile/config_test/PlaintextNames.conf
renamed:    cryptfs/config_test/StrangeFeature.conf -> internal/configfile/config_test/StrangeFeature.conf
renamed:    cryptfs/config_test/v1.conf -> internal/configfile/config_test/v1.conf
renamed:    cryptfs/config_test/v2.conf -> internal/configfile/config_test/v2.conf
renamed:    cryptfs/kdf.go -> internal/configfile/kdf.go
renamed:    cryptfs/kdf_test.go -> internal/configfile/kdf_test.go
renamed:    cryptfs/cryptfs_content.go -> internal/contentenc/content.go
new file:   internal/contentenc/content_api.go
renamed:    cryptfs/content_test.go -> internal/contentenc/content_test.go
renamed:    cryptfs/file_header.go -> internal/contentenc/file_header.go
renamed:    cryptfs/intrablock.go -> internal/contentenc/intrablock.go
renamed:    cryptfs/address_translation.go -> internal/contentenc/offsets.go
new file:   internal/cryptocore/crypto_api.go
renamed:    cryptfs/gcm_go1.4.go -> internal/cryptocore/gcm_go1.4.go
renamed:    cryptfs/gcm_go1.5.go -> internal/cryptocore/gcm_go1.5.go
renamed:    cryptfs/nonce.go -> internal/cryptocore/nonce.go
renamed:    cryptfs/openssl_aead.go -> internal/cryptocore/openssl_aead.go
renamed:    cryptfs/openssl_benchmark.bash -> internal/cryptocore/openssl_benchmark.bash
renamed:    cryptfs/openssl_test.go -> internal/cryptocore/openssl_test.go
new file:   internal/nametransform/name_api.go
new file:   internal/nametransform/names_core.go
renamed:    cryptfs/names_diriv.go -> internal/nametransform/names_diriv.go
renamed:    cryptfs/names_noiv.go -> internal/nametransform/names_noiv.go
renamed:    cryptfs/names_test.go -> internal/nametransform/names_test.go
new file:   internal/nametransform/pad16.go
renamed:    cryptfs/log.go -> internal/toggledlog/log.go
renamed:    cryptfs/log_go1.4.go -> internal/toggledlog/log_go1.4.go
renamed:    cryptfs/log_go1.5.go -> internal/toggledlog/log_go1.5.go
modified:   main.go
modified:   masterkey.go
modified:   pathfs_frontend/file.go
modified:   pathfs_frontend/file_holes.go
modified:   pathfs_frontend/fs.go
modified:   pathfs_frontend/fs_dir.go
modified:   pathfs_frontend/names.go
modified:   test.bash

5 files changed, 143 insertions, 119 deletions

diff --git a/pathfs_frontend/file.go b/pathfs_frontend/file.go
index 33ad0c7..387eb35 100644
--- a/pathfs_frontend/file.go
+++ b/pathfs_frontend/file.go
@@ -13,7 +13,9 @@ import (
 
 	"github.com/hanwen/go-fuse/fuse"
 	"github.com/hanwen/go-fuse/fuse/nodefs"
-	"github.com/rfjakob/gocryptfs/cryptfs"
+
+	"github.com/rfjakob/gocryptfs/internal/contentenc"
+	"github.com/rfjakob/gocryptfs/internal/toggledlog"
 )
 
 // File - based on loopbackFile in go-fuse/fuse/nodefs/files.go
@@ -29,19 +31,19 @@ type file struct {
 	// Was the file opened O_WRONLY?
 	writeOnly bool
 
-	// Parent CryptFS
-	cfs *cryptfs.CryptFS
+	// Content encryption helper
+	contentEnc *contentenc.ContentEnc
 
 	// Inode number
 	ino uint64
 
 	// File header
-	header *cryptfs.FileHeader
+	header *contentenc.FileHeader
 
 	forgotten bool
 }
 
-func NewFile(fd *os.File, writeOnly bool, cfs *cryptfs.CryptFS) nodefs.File {
+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)
@@ -49,7 +51,7 @@ func NewFile(fd *os.File, writeOnly bool, cfs *cryptfs.CryptFS) nodefs.File {
 	return &file{
 		fd:        fd,
 		writeOnly: writeOnly,
-		cfs:       cfs,
+		contentEnc: contentEnc,
 		ino:       st.Ino,
 	}
 }
@@ -71,12 +73,12 @@ func (f *file) SetInode(n *nodefs.Inode) {
 //
 // Returns io.EOF if the file is empty
 func (f *file) readHeader() error {
-	buf := make([]byte, cryptfs.HEADER_LEN)
+	buf := make([]byte, contentenc.HEADER_LEN)
 	_, err := f.fd.ReadAt(buf, 0)
 	if err != nil {
 		return err
 	}
-	h, err := cryptfs.ParseHeader(buf)
+	h, err := contentenc.ParseHeader(buf)
 	if err != nil {
 		return err
 	}
@@ -87,13 +89,13 @@ func (f *file) readHeader() error {
 
 // createHeader - create a new random header and write it to disk
 func (f *file) createHeader() error {
-	h := cryptfs.RandomHeader()
+	h := contentenc.RandomHeader()
 	buf := h.Pack()
 
 	// Prevent partially written (=corrupt) header by preallocating the space beforehand
-	err := prealloc(int(f.fd.Fd()), 0, cryptfs.HEADER_LEN)
+	err := prealloc(int(f.fd.Fd()), 0, contentenc.HEADER_LEN)
 	if err != nil {
-		cryptfs.Warn.Printf("ino%d: createHeader: prealloc failed: %s\n", f.ino, err.Error())
+		toggledlog.Warn.Printf("ino%d: createHeader: prealloc failed: %s\n", f.ino, err.Error())
 		return err
 	}
 
@@ -133,29 +135,29 @@ func (f *file) doRead(off uint64, length uint64) ([]byte, fuse.Status) {
 	}
 
 	// Read the backing ciphertext in one go
-	blocks := f.cfs.ExplodePlainRange(off, length)
+	blocks := f.contentEnc.ExplodePlainRange(off, length)
 	alignedOffset, alignedLength := blocks[0].JointCiphertextRange(blocks)
 	skip := blocks[0].Skip
-	cryptfs.Debug.Printf("JointCiphertextRange(%d, %d) -> %d, %d, %d", off, length, alignedOffset, alignedLength, 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 {
-		cryptfs.Warn.Printf("read: ReadAt: %s", err.Error())
+		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
-	cryptfs.Debug.Printf("ReadAt offset=%d bytes (%d blocks), want=%d, got=%d", alignedOffset, firstBlockNo, alignedLength, n)
+	toggledlog.Debug.Printf("ReadAt offset=%d bytes (%d blocks), want=%d, got=%d", alignedOffset, firstBlockNo, alignedLength, n)
 
 	// Decrypt it
-	plaintext, err := f.cfs.DecryptBlocks(ciphertext, firstBlockNo, f.header.Id)
+	plaintext, err := f.contentEnc.DecryptBlocks(ciphertext, firstBlockNo, f.header.Id)
 	if err != nil {
-		curruptBlockNo := firstBlockNo + f.cfs.PlainOffToBlockNo(uint64(len(plaintext)))
-		cipherOff := f.cfs.BlockNoToCipherOff(curruptBlockNo)
-		plainOff := f.cfs.BlockNoToPlainOff(curruptBlockNo)
-		cryptfs.Warn.Printf("ino%d: doRead: corrupt block #%d (plainOff=%d, cipherOff=%d)",
+		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
 	}
@@ -179,23 +181,23 @@ func (f *file) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fus
 	f.fdLock.RLock()
 	defer f.fdLock.RUnlock()
 
-	cryptfs.Debug.Printf("ino%d: FUSE Read: offset=%d length=%d", f.ino, len(buf), off)
+	toggledlog.Debug.Printf("ino%d: FUSE Read: offset=%d length=%d", f.ino, len(buf), off)
 
 	if f.writeOnly {
-		cryptfs.Warn.Printf("ino%d: Tried to read from write-only file", f.ino)
+		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 {
-		cryptfs.Warn.Printf("ino%d: Read failed with EIO, offset=%d, length=%d", f.ino, len(buf), off)
+		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
 	}
 
-	cryptfs.Debug.Printf("ino%d: Read: status %v, returning %d bytes", f.ino, status, len(out))
+	toggledlog.Debug.Printf("ino%d: Read: status %v, returning %d bytes", f.ino, status, len(out))
 	return fuse.ReadResultData(out), status
 }
 
@@ -225,7 +227,7 @@ func (f *file) doWrite(data []byte, off int64) (uint32, fuse.Status) {
 	var written uint32
 	status := fuse.OK
 	dataBuf := bytes.NewBuffer(data)
-	blocks := f.cfs.ExplodePlainRange(uint64(off), uint64(len(data)))
+	blocks := f.contentEnc.ExplodePlainRange(uint64(off), uint64(len(data)))
 	for _, b := range blocks {
 
 		blockData := dataBuf.Next(int(b.Length))
@@ -234,26 +236,26 @@ func (f *file) doWrite(data []byte, off int64) (uint32, fuse.Status) {
 		if b.IsPartial() {
 			// Read
 			o, _ := b.PlaintextRange()
-			oldData, status := f.doRead(o, f.cfs.PlainBS())
+			oldData, status := f.doRead(o, f.contentEnc.PlainBS())
 			if status != fuse.OK {
-				cryptfs.Warn.Printf("ino%d fh%d: RMW read failed: %s", f.ino, f.intFd(), status.String())
+				toggledlog.Warn.Printf("ino%d fh%d: RMW read failed: %s", f.ino, f.intFd(), status.String())
 				return written, status
 			}
 			// Modify
-			blockData = f.cfs.MergeBlocks(oldData, blockData, int(b.Skip))
-			cryptfs.Debug.Printf("len(oldData)=%d len(blockData)=%d", len(oldData), len(blockData))
+			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.cfs.EncryptBlock(blockData, b.BlockNo, f.header.Id)
-		cryptfs.Debug.Printf("ino%d: Writing %d bytes to block #%d",
-			f.ino, uint64(len(blockData))-f.cfs.BlockOverhead(), b.BlockNo)
+		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 {
-			cryptfs.Warn.Printf("ino%d fh%d: doWrite: prealloc failed: %s", f.ino, f.intFd(), err.Error())
+			toggledlog.Warn.Printf("ino%d fh%d: doWrite: prealloc failed: %s", f.ino, f.intFd(), err.Error())
 			status = fuse.ToStatus(err)
 			break
 		}
@@ -262,7 +264,7 @@ func (f *file) doWrite(data []byte, off int64) (uint32, fuse.Status) {
 		_, err = f.fd.WriteAt(blockData, int64(blockOffset))
 
 		if err != nil {
-			cryptfs.Warn.Printf("doWrite: Write failed: %s", err.Error())
+			toggledlog.Warn.Printf("doWrite: Write failed: %s", err.Error())
 			status = fuse.ToStatus(err)
 			break
 		}
@@ -278,18 +280,18 @@ func (f *file) Write(data []byte, off int64) (uint32, fuse.Status) {
 	wlock.lock(f.ino)
 	defer wlock.unlock(f.ino)
 
-	cryptfs.Debug.Printf("ino%d: FUSE Write: offset=%d length=%d", f.ino, off, len(data))
+	toggledlog.Debug.Printf("ino%d: FUSE Write: offset=%d length=%d", f.ino, off, len(data))
 
 	fi, err := f.fd.Stat()
 	if err != nil {
-		cryptfs.Warn.Printf("Write: Fstat failed: %v", err)
+		toggledlog.Warn.Printf("Write: Fstat failed: %v", err)
 		return 0, fuse.ToStatus(err)
 	}
-	plainSize := f.cfs.CipherSizeToPlainSize(uint64(fi.Size()))
+	plainSize := f.contentEnc.CipherSizeToPlainSize(uint64(fi.Size()))
 	if f.createsHole(plainSize, off) {
 		status := f.zeroPad(plainSize)
 		if status != fuse.OK {
-			cryptfs.Warn.Printf("zeroPad returned error %v", status)
+			toggledlog.Warn.Printf("zeroPad returned error %v", status)
 			return 0, status
 		}
 	}
@@ -337,14 +339,14 @@ func (f *file) Truncate(newSize uint64) fuse.Status {
 	defer wlock.unlock(f.ino)
 
 	if f.forgotten {
-		cryptfs.Warn.Printf("ino%d fh%d: Truncate on forgotten file", f.ino, f.intFd())
+		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 {
-			cryptfs.Warn.Printf("ino%d fh%d: Ftruncate(fd, 0) returned error: %v", f.ino, f.intFd(), err)
+			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
@@ -356,14 +358,14 @@ func (f *file) Truncate(newSize uint64) fuse.Status {
 	// the file
 	fi, err := f.fd.Stat()
 	if err != nil {
-		cryptfs.Warn.Printf("ino%d fh%d: Truncate: Fstat failed: %v", f.ino, f.intFd(), err)
+		toggledlog.Warn.Printf("ino%d fh%d: Truncate: Fstat failed: %v", f.ino, f.intFd(), err)
 		return fuse.ToStatus(err)
 	}
-	oldSize := f.cfs.CipherSizeToPlainSize(uint64(fi.Size()))
+	oldSize := f.contentEnc.CipherSizeToPlainSize(uint64(fi.Size()))
 	{
-		oldB := float32(oldSize) / float32(f.cfs.PlainBS())
-		newB := float32(newSize) / float32(f.cfs.PlainBS())
-		cryptfs.Debug.Printf("ino%d: FUSE Truncate from %.2f to %.2f blocks (%d to %d bytes)", f.ino, oldB, newB, oldSize, newSize)
+		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
@@ -382,7 +384,7 @@ func (f *file) Truncate(newSize uint64) fuse.Status {
 			}
 		}
 
-		blocks := f.cfs.ExplodePlainRange(oldSize, newSize-oldSize)
+		blocks := f.contentEnc.ExplodePlainRange(oldSize, newSize-oldSize)
 		for _, b := range blocks {
 			// First and last block may be partial
 			if b.IsPartial() {
@@ -396,7 +398,7 @@ func (f *file) Truncate(newSize uint64) fuse.Status {
 				off, length := b.CiphertextRange()
 				err := syscall.Ftruncate(int(f.fd.Fd()), int64(off+length))
 				if err != nil {
-					cryptfs.Warn.Printf("grow Ftruncate returned error: %v", err)
+					toggledlog.Warn.Printf("grow Ftruncate returned error: %v", err)
 					return fuse.ToStatus(err)
 				}
 			}
@@ -404,23 +406,23 @@ func (f *file) Truncate(newSize uint64) fuse.Status {
 		return fuse.OK
 	} else {
 		// File shrinks
-		blockNo := f.cfs.PlainOffToBlockNo(newSize)
-		cipherOff := f.cfs.BlockNoToCipherOff(blockNo)
-		plainOff := f.cfs.BlockNoToPlainOff(blockNo)
+		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 {
-				cryptfs.Warn.Printf("shrink doRead returned error: %v", err)
+				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 {
-			cryptfs.Warn.Printf("shrink Ftruncate returned error: %v", err)
+			toggledlog.Warn.Printf("shrink Ftruncate returned error: %v", err)
 			return fuse.ToStatus(err)
 		}
 		// Append partial block
@@ -450,14 +452,14 @@ func (f *file) GetAttr(a *fuse.Attr) fuse.Status {
 	f.fdLock.RLock()
 	defer f.fdLock.RUnlock()
 
-	cryptfs.Debug.Printf("file.GetAttr()")
+	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.cfs.CipherSizeToPlainSize(a.Size)
+	a.Size = f.contentEnc.CipherSizeToPlainSize(a.Size)
 
 	return fuse.OK
 }
@@ -468,7 +470,7 @@ var allocateWarned bool
 func (f *file) Allocate(off uint64, sz uint64, mode uint32) fuse.Status {
 	// Only warn once
 	if !allocateWarned {
-		cryptfs.Warn.Printf("fallocate(2) is not supported, returning ENOSYS - see https://github.com/rfjakob/gocryptfs/issues/1")
+		toggledlog.Warn.Printf("fallocate(2) is not supported, returning ENOSYS - see https://github.com/rfjakob/gocryptfs/issues/1")
 		allocateWarned = true
 	}
 	return fuse.ENOSYS
diff --git a/pathfs_frontend/file_holes.go b/pathfs_frontend/file_holes.go
index fd2e2c1..a147deb 100644
--- a/pathfs_frontend/file_holes.go
+++ b/pathfs_frontend/file_holes.go
@@ -4,13 +4,14 @@ package pathfs_frontend
 
 import (
 	"github.com/hanwen/go-fuse/fuse"
-	"github.com/rfjakob/gocryptfs/cryptfs"
+
+	"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.cfs.PlainOffToBlockNo(plainSize)
-	targetBlock := f.cfs.PlainOffToBlockNo(uint64(off))
+	nextBlock := f.contentEnc.PlainOffToBlockNo(plainSize)
+	targetBlock := f.contentEnc.PlainOffToBlockNo(uint64(off))
 	if targetBlock > nextBlock {
 		return true
 	}
@@ -19,10 +20,10 @@ func (f *file) createsHole(plainSize uint64, off int64) bool {
 
 // Zero-pad the file of size plainSize to the next block boundary
 func (f *file) zeroPad(plainSize uint64) fuse.Status {
-	lastBlockLen := plainSize % f.cfs.PlainBS()
-	missing := f.cfs.PlainBS() - lastBlockLen
+	lastBlockLen := plainSize % f.contentEnc.PlainBS()
+	missing := f.contentEnc.PlainBS() - lastBlockLen
 	pad := make([]byte, missing)
-	cryptfs.Debug.Printf("zeroPad: Writing %d bytes\n", 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
index a00985d..212f0a7 100644
--- a/pathfs_frontend/fs.go
+++ b/pathfs_frontend/fs.go
@@ -13,25 +13,41 @@ import (
 	"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"
+
+	"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 {
-	*cryptfs.CryptFS
 	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{
-		CryptFS:    cryptfs.NewCryptFS(args.Masterkey, args.OpenSSL, args.PlaintextNames, args.GCMIV128),
 		FileSystem: pathfs.NewLoopbackFileSystem(args.Cipherdir),
 		args:       args,
+		nameTransform: nameTransform,
+		contentEnc: contentEnc,
 	}
 }
 
@@ -43,12 +59,12 @@ func (fs *FS) getBackingPath(relPath string) (string, error) {
 		return "", err
 	}
 	cAbsPath := filepath.Join(fs.args.Cipherdir, cPath)
-	cryptfs.Debug.Printf("getBackingPath: %s + %s -> %s", fs.args.Cipherdir, relPath, cAbsPath)
+	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) {
-	cryptfs.Debug.Printf("FS.GetAttr('%s')", name)
+	toggledlog.Debug.Printf("FS.GetAttr('%s')", name)
 	if fs.isFiltered(name) {
 		return nil, fuse.EPERM
 	}
@@ -58,11 +74,11 @@ func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Stat
 	}
 	a, status := fs.FileSystem.GetAttr(cName, context)
 	if a == nil {
-		cryptfs.Debug.Printf("FS.GetAttr failed: %s", status.String())
+		toggledlog.Debug.Printf("FS.GetAttr failed: %s", status.String())
 		return a, status
 	}
 	if a.IsRegular() {
-		a.Size = fs.CipherSizeToPlainSize(a.Size)
+		a.Size = fs.contentEnc.CipherSizeToPlainSize(a.Size)
 	} else if a.IsSymlink() {
 		target, _ := fs.Readlink(name, context)
 		a.Size = uint64(len(target))
@@ -71,7 +87,7 @@ func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Stat
 }
 
 func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, fuse.Status) {
-	cryptfs.Debug.Printf("OpenDir(%s)", dirName)
+	toggledlog.Debug.Printf("OpenDir(%s)", dirName)
 	cDirName, err := fs.encryptPath(dirName)
 	if err != nil {
 		return nil, fuse.ToStatus(err)
@@ -81,12 +97,12 @@ func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, f
 	if cipherEntries == nil {
 		return nil, status
 	}
-	// Get DirIV (stays zero if DirIV if off)
-	cachedIV := make([]byte, cryptfs.DIRIV_LEN)
+	// 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.CryptFS.ReadDirIV(cDirAbsPath)
+		cachedIV, err = fs.nameTransform.ReadDirIV(cDirAbsPath)
 		if err != nil {
 			return nil, fuse.ToStatus(err)
 		}
@@ -95,19 +111,19 @@ func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, f
 	var plain []fuse.DirEntry
 	for i := range cipherEntries {
 		cName := cipherEntries[i].Name
-		if dirName == "" && cName == cryptfs.ConfDefaultName {
+		if dirName == "" && cName == configfile.ConfDefaultName {
 			// silently ignore "gocryptfs.conf" in the top level dir
 			continue
 		}
-		if fs.args.DirIV && cName == cryptfs.DIRIV_FILENAME {
+		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.CryptFS.DecryptName(cName, cachedIV, fs.args.EMENames)
+			name, err = fs.nameTransform.DecryptName(cName, cachedIV)
 			if err != nil {
-				cryptfs.Warn.Printf("Invalid name \"%s\" in dir \"%s\": %s", cName, cDirName, err)
+				toggledlog.Warn.Printf("Invalid name \"%s\" in dir \"%s\": %s", cName, cDirName, err)
 				continue
 			}
 		}
@@ -137,16 +153,16 @@ func (fs *FS) Open(path string, flags uint32, context *fuse.Context) (fuseFile n
 	iflags, writeOnly := fs.mangleOpenFlags(flags)
 	cPath, err := fs.getBackingPath(path)
 	if err != nil {
-		cryptfs.Debug.Printf("Open: getBackingPath: %v", err)
+		toggledlog.Debug.Printf("Open: getBackingPath: %v", err)
 		return nil, fuse.ToStatus(err)
 	}
-	cryptfs.Debug.Printf("Open: %s", cPath)
+	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.CryptFS), fuse.OK
+	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) {
@@ -162,7 +178,7 @@ func (fs *FS) Create(path string, flags uint32, mode uint32, context *fuse.Conte
 	if err != nil {
 		return nil, fuse.ToStatus(err)
 	}
-	return NewFile(f, writeOnly, fs.CryptFS), fuse.OK
+	return NewFile(f, writeOnly, fs.contentEnc), fuse.OK
 }
 
 func (fs *FS) Chmod(path string, mode uint32, context *fuse.Context) (code fuse.Status) {
@@ -203,7 +219,7 @@ var truncateWarned bool
 func (fs *FS) Truncate(path string, offset uint64, context *fuse.Context) (code fuse.Status) {
 	// Only warn once
 	if !truncateWarned {
-		cryptfs.Warn.Printf("truncate(2) is not supported, returning ENOSYS - use ftruncate(2)")
+		toggledlog.Warn.Printf("truncate(2) is not supported, returning ENOSYS - use ftruncate(2)")
 		truncateWarned = true
 	}
 	return fuse.ENOSYS
@@ -233,7 +249,7 @@ func (fs *FS) Readlink(path string, context *fuse.Context) (out string, status f
 	if !fs.args.DirIV {
 		target, err := fs.decryptPath(cTarget)
 		if err != nil {
-			cryptfs.Warn.Printf("Readlink: CBC decryption failed: %v", err)
+			toggledlog.Warn.Printf("Readlink: CBC decryption failed: %v", err)
 			return "", fuse.EIO
 		}
 		return target, fuse.OK
@@ -241,12 +257,12 @@ func (fs *FS) Readlink(path string, context *fuse.Context) (out string, status f
 	// Since gocryptfs v0.5 symlinks are encrypted like file contents (GCM)
 	cBinTarget, err := base64.URLEncoding.DecodeString(cTarget)
 	if err != nil {
-		cryptfs.Warn.Printf("Readlink: %v", err)
+		toggledlog.Warn.Printf("Readlink: %v", err)
 		return "", fuse.EIO
 	}
-	target, err := fs.CryptFS.DecryptBlock([]byte(cBinTarget), 0, nil)
+	target, err := fs.contentEnc.DecryptBlock([]byte(cBinTarget), 0, nil)
 	if err != nil {
-		cryptfs.Warn.Printf("Readlink: %v", err)
+		toggledlog.Warn.Printf("Readlink: %v", err)
 		return "", fuse.EIO
 	}
 	return string(target), fuse.OK
@@ -264,7 +280,7 @@ func (fs *FS) Unlink(path string, context *fuse.Context) (code fuse.Status) {
 }
 
 func (fs *FS) Symlink(target string, linkName string, context *fuse.Context) (code fuse.Status) {
-	cryptfs.Debug.Printf("Symlink(\"%s\", \"%s\")", target, linkName)
+	toggledlog.Debug.Printf("Symlink(\"%s\", \"%s\")", target, linkName)
 	if fs.isFiltered(linkName) {
 		return fuse.EPERM
 	}
@@ -276,18 +292,18 @@ func (fs *FS) Symlink(target string, linkName string, context *fuse.Context) (co
 	if !fs.args.DirIV {
 		cTarget, err := fs.encryptPath(target)
 		if err != nil {
-			cryptfs.Warn.Printf("Symlink: BUG: we should not get an error here: %v", err)
+			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.CryptFS.EncryptBlock([]byte(target), 0, nil)
+	cBinTarget := fs.contentEnc.EncryptBlock([]byte(target), 0, nil)
 	cTarget := base64.URLEncoding.EncodeToString(cBinTarget)
 
 	err = os.Symlink(cTarget, cPath)
-	cryptfs.Debug.Printf("Symlink: os.Symlink(%s, %s) = %v", cTarget, cPath, err)
+	toggledlog.Debug.Printf("Symlink: os.Symlink(%s, %s) = %v", cTarget, cPath, err)
 	return fuse.ToStatus(err)
 }
 
@@ -305,7 +321,7 @@ func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (cod
 	}
 	// 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.CryptFS.DirIVCache.Clear()
+	fs.nameTransform.DirIVCache.Clear()
 
 	err = os.Rename(cOldPath, cNewPath)
 
@@ -313,7 +329,7 @@ func (fs *FS) Rename(oldPath string, newPath string, context *fuse.Context) (cod
 		// 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.
-		cryptfs.Debug.Printf("Rename: Handling ENOTEMPTY")
+		toggledlog.Debug.Printf("Rename: Handling ENOTEMPTY")
 		if fs.Rmdir(newPath, context) == fuse.OK {
 			err = os.Rename(cOldPath, cNewPath)
 		}
diff --git a/pathfs_frontend/fs_dir.go b/pathfs_frontend/fs_dir.go
index b1edd73..d378d28 100644
--- a/pathfs_frontend/fs_dir.go
+++ b/pathfs_frontend/fs_dir.go
@@ -9,7 +9,10 @@ import (
 	"syscall"
 
 	"github.com/hanwen/go-fuse/fuse"
-	"github.com/rfjakob/gocryptfs/cryptfs"
+
+	"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) {
@@ -29,7 +32,7 @@ func (fs *FS) Mkdir(relPath string, mode uint32, context *fuse.Context) (code fu
 	mode = mode | 0300
 
 	// The new directory may take the place of an older one that is still in the cache
-	fs.CryptFS.DirIVCache.Clear()
+	fs.nameTransform.DirIVCache.Clear()
 	// Create directory
 	fs.dirIVLock.Lock()
 	defer fs.dirIVLock.Unlock()
@@ -38,13 +41,13 @@ func (fs *FS) Mkdir(relPath string, mode uint32, context *fuse.Context) (code fu
 		return fuse.ToStatus(err)
 	}
 	// Create gocryptfs.diriv inside
-	err = cryptfs.WriteDirIV(encPath)
+	err = nametransform.WriteDirIV(encPath)
 	if err != nil {
 		// This should not happen
-		cryptfs.Warn.Printf("Mkdir: WriteDirIV failed: %v", err)
+		toggledlog.Warn.Printf("Mkdir: WriteDirIV failed: %v", err)
 		err2 := syscall.Rmdir(encPath)
 		if err2 != nil {
-			cryptfs.Warn.Printf("Mkdir: Rmdir rollback failed: %v", err2)
+			toggledlog.Warn.Printf("Mkdir: Rmdir rollback failed: %v", err2)
 		}
 		return fuse.ToStatus(err)
 	}
@@ -53,7 +56,7 @@ func (fs *FS) Mkdir(relPath string, mode uint32, context *fuse.Context) (code fu
 	if origMode != mode {
 		err = os.Chmod(encPath, os.FileMode(origMode))
 		if err != nil {
-			cryptfs.Warn.Printf("Mkdir: Chmod failed: %v", err)
+			toggledlog.Warn.Printf("Mkdir: Chmod failed: %v", err)
 		}
 	}
 
@@ -74,17 +77,17 @@ func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
 	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
-		cryptfs.Debug.Printf("Rmdir: handling EACCESS")
+		toggledlog.Debug.Printf("Rmdir: handling EACCESS")
 		fi, err2 := os.Stat(encPath)
 		if err2 != nil {
-			cryptfs.Debug.Printf("Rmdir: Stat: %v", err2)
+			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 {
-			cryptfs.Debug.Printf("Rmdir: Chmod failed: %v", err2)
+			toggledlog.Debug.Printf("Rmdir: Chmod failed: %v", err2)
 			return fuse.ToStatus(err)
 		}
 		defer func() {
@@ -92,7 +95,7 @@ func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
 				// Undo the chmod if removing the directory failed
 				err3 := os.Chmod(encPath, origMode)
 				if err3 != nil {
-					cryptfs.Warn.Printf("Rmdir: Chmod rollback failed: %v", err2)
+					toggledlog.Warn.Printf("Rmdir: Chmod rollback failed: %v", err2)
 				}
 			}
 		}()
@@ -100,35 +103,36 @@ func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
 		fd, err = os.Open(encPath)
 	}
 	if err != nil {
-		cryptfs.Debug.Printf("Rmdir: Open: %v", err)
+		toggledlog.Debug.Printf("Rmdir: Open: %v", err)
 		return fuse.ToStatus(err)
 	}
 	list, err := fd.Readdirnames(10)
 	fd.Close()
 	if err != nil {
-		cryptfs.Debug.Printf("Rmdir: Readdirnames: %v", err)
+		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 {
-		cryptfs.Warn.Printf("Rmdir: gocryptfs.diriv missing, allowing deletion")
+		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, cryptfs.DIRIV_FILENAME)
+	dirivPath := filepath.Join(encPath, nametransform.DirIVFilename)
 	parentDir := filepath.Dir(encPath)
-	tmpName := fmt.Sprintf("gocryptfs.diriv.rmdir.%d", cryptfs.RandUint64())
+	tmpName := fmt.Sprintf("gocryptfs.diriv.rmdir.%d", cryptocore.RandUint64())
 	tmpDirivPath := filepath.Join(parentDir, tmpName)
-	cryptfs.Debug.Printf("Rmdir: Renaming %s to %s", cryptfs.DIRIV_FILENAME, tmpDirivPath)
+	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 {
-		cryptfs.Warn.Printf("Rmdir: Renaming %s to %s failed: %v", cryptfs.DIRIV_FILENAME, tmpDirivPath, err)
+		toggledlog.Warn.Printf("Rmdir: Renaming %s to %s failed: %v",
+			nametransform.DirIVFilename, tmpDirivPath, err)
 		return fuse.ToStatus(err)
 	}
 	// Actual Rmdir
@@ -138,16 +142,16 @@ func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {
 		// meantime, undo the rename
 		err2 := os.Rename(tmpDirivPath, dirivPath)
 		if err2 != nil {
-			cryptfs.Warn.Printf("Rmdir: Rename rollback failed: %v", err2)
+			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 {
-		cryptfs.Warn.Printf("Rmdir: Could not clean up %s: %v", tmpName, err)
+		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.CryptFS.DirIVCache.Clear()
+	fs.nameTransform.DirIVCache.Clear()
 	return fuse.OK
 }
diff --git a/pathfs_frontend/names.go b/pathfs_frontend/names.go
index bd7a249..160fa0a 100644
--- a/pathfs_frontend/names.go
+++ b/pathfs_frontend/names.go
@@ -3,7 +3,8 @@ package pathfs_frontend
 // This file forwards file encryption operations to cryptfs
 
 import (
-	"github.com/rfjakob/gocryptfs/cryptfs"
+	"github.com/rfjakob/gocryptfs/internal/configfile"
+	mylog "github.com/rfjakob/gocryptfs/internal/toggledlog"
 )
 
 // isFiltered - check if plaintext "path" should be forbidden
@@ -14,9 +15,9 @@ func (fs *FS) isFiltered(path string) bool {
 		return false
 	}
 	// gocryptfs.conf in the root directory is forbidden
-	if path == cryptfs.ConfDefaultName {
-		cryptfs.Info.Printf("The name /%s is reserved when -plaintextnames is used\n",
-			cryptfs.ConfDefaultName)
+	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
@@ -30,11 +31,11 @@ func (fs *FS) encryptPath(plainPath string) (string, error) {
 		return plainPath, nil
 	}
 	if !fs.args.DirIV {
-		return fs.CryptFS.EncryptPathNoIV(plainPath), nil
+		return fs.nameTransform.EncryptPathNoIV(plainPath), nil
 	}
 	fs.dirIVLock.RLock()
 	defer fs.dirIVLock.RUnlock()
-	return fs.CryptFS.EncryptPathDirIV(plainPath, fs.args.Cipherdir, fs.args.EMENames)
+	return fs.nameTransform.EncryptPathDirIV(plainPath, fs.args.Cipherdir)
 }
 
 // decryptPath - decrypt relative ciphertext path
@@ -43,9 +44,9 @@ func (fs *FS) decryptPath(cipherPath string) (string, error) {
 		return cipherPath, nil
 	}
 	if !fs.args.DirIV {
-		return fs.CryptFS.DecryptPathNoIV(cipherPath)
+		return fs.nameTransform.DecryptPathNoIV(cipherPath)
 	}
 	fs.dirIVLock.RLock()
 	defer fs.dirIVLock.RUnlock()
-	return fs.CryptFS.DecryptPathDirIV(cipherPath, fs.args.Cipherdir, fs.args.EMENames)
+	return fs.nameTransform.DecryptPathDirIV(cipherPath, fs.args.Cipherdir, fs.args.EMENames)
 }