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authorJakob Unterwurzacher2020-08-01 20:47:59 +0200
committerJakob Unterwurzacher2020-08-01 21:14:10 +0200
commit13dc7657ba0aac4da3f4b80ba231a919fdfae0f5 (patch)
treed13781bacb4a02327f519d399e946f83fd13e5c7 /internal/fusefrontend_reverse/reverse_longnames.go
parentdd3d8c100bc9e84c44b2efb55e536b2fc0ded37e (diff)
v2api/reverse: move old fusefrontend_reverse out of the way
fusefrontend_reverse -> fusefrontend_reverse_v1api
Diffstat (limited to 'internal/fusefrontend_reverse/reverse_longnames.go')
-rw-r--r--internal/fusefrontend_reverse/reverse_longnames.go126
1 files changed, 0 insertions, 126 deletions
diff --git a/internal/fusefrontend_reverse/reverse_longnames.go b/internal/fusefrontend_reverse/reverse_longnames.go
deleted file mode 100644
index f1576d2..0000000
--- a/internal/fusefrontend_reverse/reverse_longnames.go
+++ /dev/null
@@ -1,126 +0,0 @@
-package fusefrontend_reverse
-
-import (
- "log"
- "path/filepath"
- "sync"
- "syscall"
- "time"
-
- "golang.org/x/sys/unix"
-
- "github.com/hanwen/go-fuse/v2/fuse"
- "github.com/hanwen/go-fuse/v2/fuse/nodefs"
-
- "github.com/rfjakob/gocryptfs/internal/nametransform"
- "github.com/rfjakob/gocryptfs/internal/pathiv"
- "github.com/rfjakob/gocryptfs/internal/syscallcompat"
- "github.com/rfjakob/gocryptfs/internal/tlog"
-)
-
-const (
- // File names are padded to 16-byte multiples, encrypted and
- // base64-encoded. We can encode at most 176 bytes to stay below the 255
- // bytes limit:
- // * base64(176 bytes) = 235 bytes
- // * base64(192 bytes) = 256 bytes (over 255!)
- // But the PKCS#7 padding is at least one byte. This means we can only use
- // 175 bytes for the file name.
- shortNameMax = 175
-)
-
-// longnameParentCache maps dir+"/"+longname to plaintextname.
-// Yes, the combination of relative plaintext dir path and encrypted
-// longname is strange, but works fine as a map index.
-var longnameParentCache map[string]string
-var longnameCacheLock sync.Mutex
-
-// Very simple cache cleaner: Nuke it every hour
-func longnameCacheCleaner() {
- for {
- time.Sleep(time.Hour)
- longnameCacheLock.Lock()
- longnameParentCache = map[string]string{}
- longnameCacheLock.Unlock()
- }
-}
-
-func initLongnameCache() {
- if longnameParentCache != nil {
- return
- }
- longnameParentCache = map[string]string{}
- go longnameCacheCleaner()
-}
-
-// findLongnameParent converts "longname" = "gocryptfs.longname.XYZ" to the
-// plaintext name. "dir" = relative plaintext path to the directory the
-// longname file is in, "dirIV" = directory IV of the directory.
-func (rfs *ReverseFS) findLongnameParent(dir string, dirIV []byte, longname string) (plaintextName string, err error) {
- longnameCacheLock.Lock()
- hit := longnameParentCache[dir+"/"+longname]
- longnameCacheLock.Unlock()
- if hit != "" {
- return hit, nil
- }
- dirfd, err := syscallcompat.OpenDirNofollow(rfs.args.Cipherdir, filepath.Dir(dir))
- if err != nil {
- tlog.Warn.Printf("findLongnameParent: OpenDirNofollow failed: %v\n", err)
- return "", err
- }
- fd, err := syscallcompat.Openat(dirfd, filepath.Base(dir), syscall.O_RDONLY|syscall.O_DIRECTORY|syscall.O_NOFOLLOW, 0)
- syscall.Close(dirfd)
- if err != nil {
- tlog.Warn.Printf("findLongnameParent: Openat failed: %v\n", err)
- return "", err
- }
- dirEntries, err := syscallcompat.Getdents(fd)
- syscall.Close(fd)
- if err != nil {
- tlog.Warn.Printf("findLongnameParent: Getdents failed: %v\n", err)
- return "", err
- }
- longnameCacheLock.Lock()
- defer longnameCacheLock.Unlock()
- for _, entry := range dirEntries {
- plaintextName := entry.Name
- if len(plaintextName) <= shortNameMax {
- continue
- }
- cName := rfs.nameTransform.EncryptName(plaintextName, dirIV)
- if len(cName) <= unix.NAME_MAX {
- // Entry should have been skipped by the "continue" above
- log.Panic("logic error or wrong shortNameMax constant?")
- }
- hName := rfs.nameTransform.HashLongName(cName)
- longnameParentCache[dir+"/"+hName] = plaintextName
- if longname == hName {
- hit = plaintextName
- }
- }
- if hit == "" {
- return "", syscall.ENOENT
- }
- return hit, nil
-}
-
-func (rfs *ReverseFS) newNameFile(relPath string) (nodefs.File, fuse.Status) {
- dotName := filepath.Base(relPath) // gocryptfs.longname.XYZ.name
- longname := nametransform.RemoveLongNameSuffix(dotName) // gocryptfs.longname.XYZ
- // cipher directory
- cDir := nametransform.Dir(relPath)
- // plain directory
- pDir, err := rfs.decryptPath(cDir)
- if err != nil {
- return nil, fuse.ToStatus(err)
- }
- dirIV := pathiv.Derive(cDir, pathiv.PurposeDirIV)
- // plain name
- pName, err := rfs.findLongnameParent(pDir, dirIV, longname)
- if err != nil {
- return nil, fuse.ToStatus(err)
- }
- content := []byte(rfs.nameTransform.EncryptName(pName, dirIV))
- parentFile := filepath.Join(pDir, pName)
- return rfs.newVirtualFile(content, rfs.args.Cipherdir, parentFile, inoTagNameFile)
-}