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Diffstat (limited to 'internal/nametransform/names_diriv.go')
-rw-r--r--internal/nametransform/names_diriv.go143
1 files changed, 0 insertions, 143 deletions
diff --git a/internal/nametransform/names_diriv.go b/internal/nametransform/names_diriv.go
deleted file mode 100644
index b9473aa..0000000
--- a/internal/nametransform/names_diriv.go
+++ /dev/null
@@ -1,143 +0,0 @@
-package nametransform
-
-import (
- "errors"
- "io/ioutil"
- "os"
- "path/filepath"
- "strings"
- "syscall"
-
- "github.com/rfjakob/gocryptfs/internal/cryptocore"
- "github.com/rfjakob/gocryptfs/internal/tlog"
-)
-
-const (
- // identical to AES block size
- dirIVLen = 16
- // dirIV is stored in this file. Exported because we have to ignore this
- // name in directory listing.
- DirIVFilename = "gocryptfs.diriv"
-)
-
-// ReadDirIV - read the "gocryptfs.diriv" file from "dir" (absolute ciphertext path)
-// This function is exported because it allows for an efficient readdir implementation.
-func ReadDirIV(dir string) (iv []byte, err error) {
- dirfd, err := os.Open(dir)
- if err != nil {
- return nil, err
- }
- defer dirfd.Close()
-
- return ReadDirIVAt(dirfd)
-}
-
-// ReadDirIVAt reads "gocryptfs.diriv" from the directory that is opened as "dirfd".
-// Using the dirfd makes it immune to concurrent renames of the directory.
-func ReadDirIVAt(dirfd *os.File) (iv []byte, err error) {
- fdRaw, err := syscall.Openat(int(dirfd.Fd()), DirIVFilename, syscall.O_RDONLY, 0)
- if err != nil {
- tlog.Warn.Printf("ReadDirIVAt: opening %q in dir %q failed: %v",
- DirIVFilename, dirfd.Name(), err)
- return nil, err
- }
- fd := os.NewFile(uintptr(fdRaw), DirIVFilename)
- defer fd.Close()
-
- iv = make([]byte, dirIVLen+1)
- n, err := fd.Read(iv)
- if err != nil {
- tlog.Warn.Printf("ReadDirIVAt: Read failed: %v", err)
- return nil, err
- }
- iv = iv[0:n]
- if len(iv) != dirIVLen {
- tlog.Warn.Printf("ReadDirIVAt: wanted %d bytes, got %d", dirIVLen, len(iv))
- return nil, errors.New("invalid iv length")
- }
- return iv, nil
-}
-
-// WriteDirIV - create diriv file inside "dir" (absolute ciphertext path)
-// This function is exported because it is used from pathfs_frontend, main,
-// and also the automated tests.
-func WriteDirIV(dir string) error {
- iv := cryptocore.RandBytes(dirIVLen)
- file := filepath.Join(dir, DirIVFilename)
- err := ioutil.WriteFile(file, iv, 0400)
- if err != nil {
- tlog.Warn.Printf("WriteDirIV: %v", err)
- }
- return err
-}
-
-// EncryptPathDirIV - encrypt relative plaintext path using EME with DirIV.
-// Components that are longer than 255 bytes are hashed if be.longnames == true.
-func (be *NameTransform) EncryptPathDirIV(plainPath string, rootDir string) (cipherPath string, err error) {
- // Empty string means root directory
- if plainPath == "" {
- return plainPath, nil
- }
- // Reject names longer than 255 bytes already here. This relieves everybody
- // who uses hashed long names from checking for that later.
- baseName := filepath.Base(plainPath)
- if len(baseName) > syscall.NAME_MAX {
- return "", syscall.ENAMETOOLONG
- }
- // Check if the DirIV is cached
- parentDir := filepath.Dir(plainPath)
- found, iv, cParentDir := be.DirIVCache.lookup(parentDir)
- if found {
- cBaseName := be.EncryptName(baseName, iv)
- if be.longNames && len(cBaseName) > syscall.NAME_MAX {
- cBaseName = HashLongName(cBaseName)
- }
- cipherPath = cParentDir + "/" + cBaseName
- return cipherPath, nil
- }
- // Not cached - walk the directory tree
- var wd = rootDir
- var encryptedNames []string
- plainNames := strings.Split(plainPath, "/")
- for _, plainName := range plainNames {
- iv, err = ReadDirIV(wd)
- if err != nil {
- return "", err
- }
- encryptedName := be.EncryptName(plainName, iv)
- if be.longNames && len(encryptedName) > syscall.NAME_MAX {
- encryptedName = HashLongName(encryptedName)
- }
- encryptedNames = append(encryptedNames, encryptedName)
- wd = filepath.Join(wd, encryptedName)
- }
- cipherPath = strings.Join(encryptedNames, "/")
- // Cache the final DirIV
- cParentDir = filepath.Dir(cipherPath)
- be.DirIVCache.store(parentDir, iv, cParentDir)
- return cipherPath, nil
-}
-
-// DecryptPathDirIV - decrypt path using EME with DirIV
-//
-// TODO This has only a single user, Readlink(), and only for compatability with
-// gocryptfs v0.5. Drop?
-func (be *NameTransform) DecryptPathDirIV(encryptedPath string, rootDir string) (string, error) {
- var wd = rootDir
- var plainNames []string
- encryptedNames := strings.Split(encryptedPath, "/")
- tlog.Debug.Printf("DecryptPathDirIV: decrypting %v\n", encryptedNames)
- for _, encryptedName := range encryptedNames {
- iv, err := ReadDirIV(wd)
- if err != nil {
- return "", err
- }
- plainName, err := be.DecryptName(encryptedName, iv)
- if err != nil {
- return "", err
- }
- plainNames = append(plainNames, plainName)
- wd = filepath.Join(wd, encryptedName)
- }
- return filepath.Join(plainNames...), nil
-}