Fix symlink size reporting

cryptfs/cryptfs_content.go

@@ -97,12 +97,20 @@ func (be *CryptFS) SplitRange(offset uint64, length uint64) []intraBlock {
 
 // PlainSize - calculate plaintext size from ciphertext size
 func (be *CryptFS) PlainSize(size uint64) uint64 {
+
 	// Zero sized files stay zero-sized
-	if size > 0 {
+	if size == 0 {
+		return 0
+	}
+
 	overhead := be.cipherBS - be.plainBS
 	nBlocks := (size + be.cipherBS - 1) / be.cipherBS
-		size -= nBlocks * overhead
+	if nBlocks * overhead > size {
+		Warn.Printf("PlainSize: Negative size, returning 0 instead\n")
+		return 0
 	}
+	size -= nBlocks * overhead
+
 	return size
 }
 

cryptfs/log.go

@@ -26,4 +26,5 @@ func (l *logChannel) Enable() {
 
 
 var Debug = logChannel{false}
+var Notice = logChannel{true}
 var Warn = logChannel{true}

main.go

@@ -64,10 +64,10 @@ func initDir(dirArg string) {
 
 func main() {
 	// Parse command line arguments
-	var debug bool
+	var debug, init, zerokey, fusedebug bool
-	var init bool
+
-	var zerokey bool
 	flag.BoolVar(&debug, "debug", false, "Enable debug output")
+	flag.BoolVar(&fusedebug, "fusedebug", false, "Enable fuse library debug output")
 	flag.BoolVar(&init, "init", false, "Initialize encrypted directory")
 	flag.BoolVar(&zerokey, "zerokey", false, "Use all-zero dummy master key")
 	flag.Parse()
@@ -123,7 +123,7 @@ func main() {
 	if USE_CLUEFS {
 		cluefsFrontend(key, cipherdir, mountpoint)
 	} else {
-		pathfsFrontend(key, cipherdir, mountpoint, debug)
+		pathfsFrontend(key, cipherdir, mountpoint, fusedebug)
 	}
 }
 

pathfs_frontend/file.go

@@ -210,6 +210,7 @@ func (f *file) Chown(uid uint32, gid uint32) fuse.Status {
 }
 
 func (f *file) GetAttr(a *fuse.Attr) fuse.Status {
+	cryptfs.Debug.Printf("file.GetAttr()\n")
 	st := syscall.Stat_t{}
 	f.lock.Lock()
 	err := syscall.Fstat(int(f.fd.Fd()), &st)

pathfs_frontend/fs.go

@@ -34,16 +34,24 @@ func (fs *FS) GetPath(relPath string) string {
 }
 
 func (fs *FS) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
-	a, status := fs.FileSystem.GetAttr(fs.EncryptPath(name), context)
+	cryptfs.Debug.Printf("FS.GetAttr('%s')\n", name)
+	cName := fs.EncryptPath(name)
+	a, status := fs.FileSystem.GetAttr(cName, context)
 	if a == nil {
+		cryptfs.Notice.Printf("FS.GetAttr failed: %s\n", status.String())
 		return a, status
 	}
-
+	if a.IsRegular() {
 		a.Size = fs.PlainSize(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) {
+	cryptfs.Debug.Printf("OpenDir(%s)\n", dirName)
 	cipherEntries, status := fs.FileSystem.OpenDir(fs.EncryptPath(dirName), context);
 	var plain []fuse.DirEntry
 	if cipherEntries != nil {
@@ -137,7 +145,12 @@ func (fs *FS) Mkdir(path string, mode uint32, context *fuse.Context) (code fuse.
 }
 
 func (fs *FS) Unlink(name string, context *fuse.Context) (code fuse.Status) {
-	return fs.FileSystem.Unlink(fs.EncryptPath(name), context)
+	cName := fs.EncryptPath(name)
+	code = fs.FileSystem.Unlink(cName, context)
+	if code != fuse.OK {
+		cryptfs.Notice.Printf("Unlink failed on %s [%s], code=%s\n", name, cName, code.String())
+	}
+	return code
 }
 
 func (fs *FS) Rmdir(name string, context *fuse.Context) (code fuse.Status) {