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Diffstat (limited to 'pathfs_frontend/fs.go')
-rw-r--r--pathfs_frontend/fs.go381
1 files changed, 0 insertions, 381 deletions
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
-}