IMPORTANT: If you store the backup volume in any location that an adversary can
repeatedly access (for example, on a device kept in a bank’s safe deposit box), you should
repeat all of the above steps (including the step 2) each time you want to back up the
volume (see below).
If you follow the above steps, you will help prevent adversaries from finding out:
•
Which sectors of the volumes are changing (because you always follow step 2). This is
particularly important, for example, if you store the backup volume on a device kept in a
bank’s safe deposit box (or in any other location that an adversary can repeatedly access)
and the volume contains a hidden volume (for more information, see the subsection
Security Requirements and Precautions Pertaining to Hidden Volumes
in the chapter
Plausible Deniability
).
•
That one of the volumes is a backup of the other.
General Notes
If you store the backup volume in any location where an adversary can make a copy of the volume,
consider encrypting the volume with a cascade of ciphers (for example, with AES-Twofish-
Serpent). Otherwise, if the volume is encrypted only with a single encryption algorithm and the
algorithm is later broken (for example, due to advances in cryptanalysis), the attacker might be
able to decrypt his copies of the volume. The probability that three distinct encryption algorithms
will be broken is significantly lower than the probability that only one of them will be broken.
99
Miscellaneous
Using TrueCrypt Without Administrator Privileges
In Windows, a user who does not have administrator privileges
can
use TrueCrypt, but only after a
system administrator installs TrueCrypt on the system. The reason for that is that TrueCrypt needs
a device driver to provide transparent on-the-fly encryption/decryption, and users without
administrator privileges cannot install/start device drivers in Windows.
After a system administrator installs TrueCrypt on the system, users without administrator
privileges will be able to run TrueCrypt, mount/dismount any type of TrueCrypt volume, load/save
data from/to it, and create file-hosted TrueCrypt volumes on the system. However, users without
administrator privileges cannot encrypt/format partitions, cannot create NTFS volumes, cannot
install/uninstall TrueCrypt, cannot change passwords/keyfiles for TrueCrypt partitions/devices,
cannot backup/restore headers of TrueCrypt partitions/devices, and they cannot run TrueCrypt in
‘portable’ mode.
Warning: No matter what kind of software you use, as regards personal privacy in most
cases, it is
not
safe to work with sensitive data under systems where you do not have
administrator privileges, as the administrator can easily capture and copy your sensitive data,
including passwords and keys.
|