libgocryptfs/internal/fusefrontend_reverse/rpath.go
Jakob Unterwurzacher a6a7b424f8 reverse: resolve long names in Open and GetAttr
The last patch added functionality for generating gocryptfs.longname.*
files, this patch adds support for mapping them back to the full
filenames.

Note that resolving a long name needs a full readdir. A cache
will be implemented later on to improve performance.
2016-09-25 16:43:17 +02:00

68 lines
1.8 KiB
Go

package fusefrontend_reverse
import (
"encoding/base64"
"path/filepath"
"strings"
"syscall"
"github.com/rfjakob/gocryptfs/internal/nametransform"
)
// saneDir is like filepath.Dir but returns "" instead of "."
func saneDir(path string) string {
d := filepath.Dir(path)
if d == "." {
return ""
}
return d
}
func (rfs *reverseFS) abs(relPath string, err error) (string, error) {
if err != nil {
return "", err
}
return filepath.Join(rfs.args.Cipherdir, relPath), nil
}
func (rfs *reverseFS) decryptPath(relPath string) (string, error) {
if rfs.args.PlaintextNames || relPath == "" {
return relPath, nil
}
var err error
var transformedParts []string
parts := strings.Split(relPath, "/")
for i, part := range parts {
// Start at the top and recurse
currentDir := filepath.Join(parts[:i]...)
nameType := nametransform.NameType(part)
dirIV := deriveDirIV(currentDir)
var transformedPart string
if nameType == nametransform.LongNameNone {
transformedPart, err = rfs.nameTransform.DecryptName(part, dirIV)
if err != nil {
// We get lots of decrypt requests for names like ".Trash" that
// are invalid base64. Convert them to ENOENT so the correct
// error gets returned to the user.
if _, ok := err.(base64.CorruptInputError); ok {
return "", syscall.ENOENT
}
return "", err
}
} else if nameType == nametransform.LongNameContent {
transformedPart, err = rfs.findLongnameParent(currentDir, dirIV, part)
if err != nil {
return "", err
}
} else {
panic("longname bug, .name files should have been handled earlier")
}
transformedParts = append(transformedParts, transformedPart)
}
return filepath.Join(transformedParts...), nil
}
func (rfs *reverseFS) isFiltered(relPath string) bool {
return false
}