Method decryptFileName

backend/crypt/cipher.go:544–585

decryptFileName decrypts a file path

(in string)

// decryptFileName decrypts a file path
func (c *Cipher) decryptFileName(in string) (string, error) {
	segments := strings.Split(in, "/")
	for i := range segments {
		var err error
		// Skip directory name decryption if the user chose to
		// leave them intact
		if !c.dirNameEncrypt && i != (len(segments)-1) {
			continue
		}

		// Strip version string so that only the non-versioned part
		// of the file name gets decrypted/deobfuscated
		hasVersion := false
		var t time.Time
		if i == (len(segments)-1) && version.Match(segments[i]) {
			var s string
			t, s = version.Remove(segments[i])
			// version.Remove can fail, in which case it returns segments[i]
			if s != segments[i] {
				segments[i] = s
				hasVersion = true
			}
		}

		if c.mode == NameEncryptionStandard {
			segments[i], err = c.decryptSegment(segments[i])
		} else {
			segments[i], err = c.deobfuscateSegment(segments[i])
		}

		if err != nil {
			return "", err
		}

		// Add back a version to the decrypted/deobfuscated
		// file name, if we stripped it off earlier
		if hasVersion {
			segments[i] = version.Add(segments[i], t)
		}
	}
	return strings.Join(segments, "/"), nil
}

// DecryptFileName decrypts a file path
func (c *Cipher) DecryptFileName(in string) (string, error) {