TrueCrypt
Consider using VeraCrypt, a TrueCrypt fork in active development installable with the veracrypt package; VeraCrypt storage format is compatible with TrueCrypt storage format since version 1.0f.
On 2015/09/26 two critical vulnerabilities were published for the Windows version of TrueCrypt: CVE-2015-7358 and CVE-2015-7359. Take this into account if you are planning to use this software to share encrypted volumes between Windows and Arch Linux. More information: [2],[3][dead link 2021-11-19 ⓘ]TrueCrypt is a free open source on-the-fly encryption (OTFE) program. Some of its features are:
- Virtual encrypted disks within files that can be mounted as real disks.
- Encryption of an entire hard disk partition or a storage device/medium.
- All encryption algorithms use the LRW mode of operation, which is more secure than CBC mode with predictable initialization vectors for storage encryption.
- "Hidden volumes" within a normal "outer" encrypted volume. A hidden volume can not be distinguished from random data without access to a passphrase and/or keyfile.
For more details on how TrueCrypt compares to other disk encryption solution, see Data-at-rest encryption#Comparison table.
Installation
truecrypt, after which it can be opened using cryptsetup.Install truecrypt from the official repositories. If you use any kernel other than linux install the corresponding kernel module.
If you are using truecrypt to encrypt a virtual filesystem (e.g. a file), the module will be automatically loaded whenever you run the truecrypt command.
If you are using truecrypt to encrypt a physical device (e.g. a hard disk or usb drive), you will likely want to load the module during the boot sequence:
Add the module to /etc/modules-load.d/:
# tee /etc/modules-load.d/truecrypt.conf <<< "truecrypt"
- This did not work for me (module truecrypt seems to be non-existent now), but adding "loop" module worked
# tee /etc/modules-load.d/truecrypt.conf <<< "loop" # modprobe loop
- It does not appear that loading a module applies with TrueCrypt 7.1a, the current version in Arch as of 4/19/2013. The above advice may be outdated with respect to the module, however it is still important to enable FUSE, loop and your encryption algorithm (e.g. AES, XTS, SHA512) in custom kernels.
If you only want to open and access an existing truecrypt container, this can also be done with cryptsetup i.e. without installing Truecrypt.
Accessing a TrueCrypt or VeraCrypt container using cryptsetup
Since version 1.6.7, cryptsetup supports opening TrueCrypt and VeraCrypt containers natively, without the need of the truecrypt or veracrypt package. Use the following command as a guideline.
$ cryptsetup --type tcrypt open container-to-mount container-name
To mount a VeraCrypt cointainer, you must use the --veracrypt option alongside --type tcrypt. If using a custom Personal Iteration Multiplier (PIM), use the --veracrypt-query-pim option to be promoted for the PIM.
Replace container-to-mount with the device file under /dev or the path to the file you wish to open. Upon successful opening, the plaintext device will appear as /dev/mapper/container-name, which you can mount like any normal device.
If you are using key files, supply them using the --key-file option, to open a hidden volume, supply the --tcrypt-hidden option and for a partition or whole drive that is encrypted in system mode use the --tcrypt-system option.
See cryptsetup(8) for more details and all supported options.
Automounting using /etc/crypttab
Since version 206, systemd supports (auto)mounting TrueCrypt containers at boot or runtime using /etc/crypttab.
The following example setup will mount /dev/sda2 in system encryption mode as soon as /mnt/truecrypt-volume is accessed using systemd's automounting logic. The passphrase to open the volume is given in /etc/volume.password. Note that the device file given in /etc/fstab needs to be the one from /dev/mapper/ and not, for example, from /dev/disk/by-uuid/ for automounting logic to kick in. Other than that you can still reliably identify the encrypted volume itself inside of /etc/crypttab using device file names from /dev/disk/.
/etc/crypttab
truecrypt-volume /dev/sda2 /etc/volume.password tcrypt-system,noauto
For a standard truecrypt volume, use tcrypt instead of tcrypt-system. And for a hidden one, use tcrypt-hidden. For a veracrypt volume, use tcrypt-veracrypt alongside tcrypt.
/etc/fstab
/dev/mapper/truecrypt-volume /mnt/truecrypt-volume auto noauto,x-systemd.automount 0 0
Instead of auto, you can put directly your filesystem, and put usual mount options. It is useful with NTFS for mounting as a normal user.
See crypttab(5) for more details and options supported.
Encrypting a file as a virtual volume
The following instructions will create a file that will act as a virtual filesystem, allowing you to mount it and store files within the encrypted file. This is a convenient way to store sensitive information, such as financial data or passwords, in a single file that can be accessed from Linux, Windows, or Macs.
To create a new truecrypt file interactively, type the following in a terminal:
$ truecrypt -t -c
Follow the instructions, choosing the default values unless you know what you are doing:
Volume type: 1) Normal 2) Hidden Select [1]: 1
Enter file or device path for new volume: /home/user/EncryptedFile.tc
Enter volume size (bytes - size/sizeK/sizeM/sizeG): 32M
Encryption algorithm: 1) AES 2) Blowfish 3) CAST5 4) Serpent 5) Triple DES 6) Twofish 7) AES-Twofish 8) AES-Twofish-Serpent 9) Serpent-AES 10) Serpent-Twofish-AES 11) Twofish-Serpent Select [1]: 1
Hash algorithm: 1) RIPEMD-160 2) SHA-1 3) Whirlpool Select [1]: 1
Filesystem:
1) None 2) FAT 3) Linux Ext2 4) Linux Ext3 5) Linux Ext4
Select [2]:
Enter password for new volume '/home/user/EncryptedFile.tc': ***************************** Re-enter password: *****************************
Enter keyfile path [none]:
Please type at least 320 randomly chosen characters and then press Enter:
Done: 32.00 MB Speed: 10.76 MB/s Left: 0:00:00 Volume created.
You can now mount the new encrypted file to a previously-created directory:
$ truecrypt -t /home/user/EncryptedFile.tc /home/user/EncryptedFileFolder
Once mounted, you can copy or create new files within the encrypted directory as if it was any normal directory. When you are you ready to re-encrypt the contents and unmount the directory, run:
$ truecrypt -t -d
Again, this will require administrator privileges through the use of sudo. After running it check if the files that are to be encrypted are indeed no longer in the directory. (might want to try unimportant data first) If they are still there, note that rm does not make the data unrecoverable.
For more information about truecrypt in general, run:
$ man truecrypt
Several options can be passed at the command line, making automated access and creation a simple task. The man page is highly recommended reading.
Encrypting a physical volume
If you want to use a keyfile, create one with this command:
truecrypt --create-keyfile /etc/disk.key
By default both passphrase and key will be needed to unlock the volume.
Create a new volume in the device /dev/sda1:
# truecrypt --volume-type=normal -c /dev/sda1
Map the volume to /dev/mapper/truecrypt1:
# truecrypt -N 1 /dev/sda1
If this command does not for you try this to map the volume:
# truecrypt --filesystem=none --slot=1 /dev/sda1
Simply format the disk like you normally would choosing your favourite file system, except use the path /dev/mapper/truecrypt1. E.g. for ext4 use:
# mkfs.ext4 /dev/mapper/truecrypt1
Mount the volume:
# mount /dev/mapper/truecrypt1 /media/disk
Map and mount a volume:
# truecrypt /dev/sda1 /media/disk
Unmount and unmap a volume:
# truecrypt -d /dev/sda1
First, create a normal outer volume as described in #Encrypting a physical volume.
Map the outer volume to /dev/mapper/truecrypt1:
# truecrypt -N 1 /dev/sda1
Create a hidden truecrypt volume in the free space of the outer volume:
# truecrypt --type hidden -c /dev/sda1
You need to use another passphrase and/or keyfile here than the one you used for the outer volume.
Unmap the outer truecrypt volume and map the hidden one:
# truecrypt -d /dev/sda1 # truecrypt -N 1 /dev/sda1
Just use the passphrase you chose for the hidden volume and TrueCrypt will automatically choose it before the outer.
Create a file system on it (if you have not already) and mount it:
# mkfs.ext4 /dev/mapper/truecrypt1 # mount /dev/mapper/truecrypt1 /media/disk
Map and mount the outer volume with the hidden write-protected:
truecrypt -P /dev/sda1 /media/disk
Mount a special filesystem
--filesystem flag no longer seems to be necessary.In the following example I want to mount a ntfs-volume, but TrueCrypt does not use ntfs-3g by default (so there is no write access; checked in version 6.1). The following command works for me:
truecrypt --filesystem=ntfs-3g --mount /file/you/want/to/mount
You may also want to mount ntfs volume without execute flag on all files
truecrypt --filesystem=ntfs-3g --fs-options=users,uid=$(id -u),gid=$(id -g),fmask=0113,dmask=0002
Mount volumes via fstab
First of all, we need to write a script which will handle the way mounting via fstab is done. Place the following in /usr/bin/mount.truecrypt:
#!/bin/sh
DEV="$1"
MNTPT="$2"
OPTIONS=""
TCOPTIONS=""
shift 3
IFS=','
for arg in $*; do
case "$arg" in
system) TCOPTIONS=(${TCOPTIONS[*]} --m=system);;
fs*) TCOPTIONS=(${TCOPTIONS[*]} --filesystem=${arg#*=});;
keyfiles*) TCOPTIONS=(${TCOPTIONS[*]} --keyfiles=${arg#*=});;
password*) TCOPTIONS=(${TCOPTIONS[*]} --password=${arg#*=}) && echo "password triggered" ;;
protect-hidden*) TCOPTIONS=(${TCOPTIONS[*]} --protect-hidden=${arg#*=});;
*) OPTIONS="${OPTIONS}${arg},";;
esac
done
/bin/truecrypt --text --non-interactive ${DEV} ${MNTPT} ${TCOPTIONS[*]} --fs-options="${OPTIONS%,*}"
Also do not forget to make the file executable.
Finally, add the device to fstab somewhat like this:
/dev/sdb3 /mnt truecrypt fs=vfat,defaults 0 0
Mount volumes as a normal user
TrueCrypt needs root privileges to work: this procedure will allow normal users to use it, also giving writing permissions to mounted volumes.
Both methods below require Sudo. Make sure it is configured before proceeding.
Method 1: add a truecrypt group
Create a new group called truecrypt and give it the necessary permissions. Any users that belongs to that group, will be able to use TrueCrypt.
# groupadd truecrypt
Edit the sudo configuration:
# visudo
Append the following lines at the bottom of the sudo configuration file:
# Users in the truecrypt group are allowed to run TrueCrypt as root. %truecrypt ALL=(root) NOPASSWD:/usr/bin/truecrypt
You can now add your users to the truecrypt group:
# gpasswd -M first_user,second_user,etc truecrypt
After that, you can mount your device by
# truecrypt --mount /path/to/device /path/to/mountpoint
Default mountpoint is /media/truecrypt1. Normally, it is not necessary to explicitly specify the filesystem of your device using the --filesystem flag.
It is definitely reasonable to give truecrypt some permission masks. Otherwise, every file on your mounted device will be executable. So instead of the above, you can use
# truecrypt --fs-options=users,uid=$(id -u),gid=$(id -g),fmask=0113,dmask=0002 --mount /PATH/TO/DEVICE /PATH/TO/MOUNTPOINT
and add this line to your bash configuration file, ~/.bashrc as an alias:
alias tc1='truecrypt --fs-options=users,uid=$(id -u),gid=$(id -g),fmask=0113,dmask=0002 --mount /path/to/device"" /path/to/mountpoint'
To mount this specific device, use
# tc1
as a normal user.
Method 2: sudo simplified
Simply enable desired user to run truecrypt without a password:
# visudo
Append the following:
USERNAME ALL = (root) NOPASSWD:/usr/bin/truecrypt
alternatively, if you make use of the wheel group:
%wheel ALL = (root) NOPASSWD:/usr/bin/truecrypt
If you have any difficulties with permissions as a normal user, just add the -u flag to the truecrypt mount command, for example:
$ truecrypt -u /home/user/EncryptedFile.tc /home/user/EncryptedFileFolder
veracrypt-1.2.4-hotfix1, the NOPASSWD: /usr/bin/veracrypt piece must be replaced with NOPASSWD: /usr/bin/veracrypt, /usr/bin/uptime. More info available at FS#64431 and [4].Automatic mount on login
Simply add:
$ truecrypt /home/user/Encrypted File.tc /home/user/Encrypted File Folder <<EOF password EOF
to your startup procedure. Do not use the -p switch, this method is more secure. Otherwise everyone can just look up the password via ps and similar tools, as it is in the process name! source
The most recent truecrypt has a couple of followup questions. If you have expect installed, this will work (assuming no keyfile and no desire to protect hidden volume), saved to a file with root-only perms called from /etc/rc.local:
#! /bin/bash expect << EOF spawn /usr/bin/truecrypt ''/path/to/EncryptedFile'' ''/mount/point'' expect "Enter password" send "volume password\n" expect "Enter keyfile" send "\n" expect "Protect hidden volume" send "\n" expect eof; EOF
Of course, this is not as secure as entering your password manually. But for some use cases, such as when your TrueCrypt filesystem is in a file on shared storage, it is better than being unencrypted.
Safely unmount and unmap volumes (on shutdown)
You can unmount a specific device by
# truecrypt -d /path/to/mountpoint
or leave away the path to unmount all truecrypt volumes.
If you want your truecrypt device to be unmounted automatically at shutdown, add the following to the file /etc/rc.local.shutdown:
if (/usr/bin/truecrypt --text --list)
then {
/usr/bin/truecrypt -d
sleep 3
}
fi
You can also leave away the sleep command, it is just to give the unmounting some time to complete before the actual shutdown.
Errors
TrueCrypt is already running
If a messagebox TrueCrypt is already running appears when starting TrueCrypt, check for a hidden file in the home directory of the concerned user called .TrueCrypt-lock-username. Substitute username with the individual username. Delete the file and start TrueCrypt again.
Deleted stale lockfile
If you always get a message "Delete stale lockfile [....]" after starting Truecrypt, the Truecrypt process with the lowest ID has to be killed during Gnome log out. Edit /etc/gdm/PostSession/Default and add the following line before exit 0:
kill $(ps -ef | grep truecrypt | tr -s ' ' | cut -d ' ' -f 2)
Issues with Unicode file/folder names
NTFS
Should files resp. folders containing Unicode characters in their names be incorrectly or not at all displayed on TrueCrypt NTFS volumes (while e. g. being correctly handled on non-encrypted NTFS partitions), first verify that you have the NTFS-3G driver installed and then create the following symlink as root:
ln -s /sbin/mount.ntfs-3g /sbin/mount.ntfs
That will cause TrueCrypt to automatically use this driver for NTFS volumes, having the same effect as the explicit use of
truecrypt --filesystem=ntfs-3g /path/to/volume
via the console.
One may also consider setting e.g.:
rw,noatime
amongst other options in the TrueCrypt GUI (Settings > Preferences > Mount Options).
FAT
Similarly, FAT32 volumes created using Windows may use Unicode rather than ISO 8859-1. In order to use UTF-8 globally, set the mount option:
iocharset=utf8
Alternatively, when mounting volumes locally use:
--fs-options=iocharset=utf8
Since linux-4.14.4, UTF8 charset is enabled by default. So in order to mount volumes using ISO 8859-1 encoding, you need to use --fs-options=utf8=no, see FS#56781.
Unmount error (device mapper)
If you always get a message "device-mapper: remove ioctl failed: Device or resource busy" when attempting to dismount your truecrypt volume, the solution is to goto: Setting > Preferences > System Integration > Kernel Service and check the box
Do not use kernel cryptographic services
Mount error (device mapper, truecrypt partition)
When attempting to mount your truecrypt volume, a message like this one may appear:
Error: device-mapper: create ioctl failed: Device or resource busy Command failed
If so, run:
# cryptsetup remove /dev/mapper/truecrypt1
Failed to set up a loop device
If you get a message "Failed to set up a loop device" when trying to create/mount a TrueCrypt volume, it may be because you updated your kernel recently without rebooting. Rebooting should fix this error.
Otherwise, check if loop has been loaded as kernel module:
$ lsmod | grep loop
If not listed, retry the TrueCrypt command after modprobe loop. Should it work, consider to add loop to the modules in /etc/modules-load.d:
# tee /etc/modules-load.d/truecrypt.conf <<< "loop"
With newer kernel versions there are no loop devices created at startup. If there are no loop devices the first time mounting a container file, TrueCrypt fails ("Failed to set up a loop device") but also creates the maximum number of loop devices (usually 256), mounting should now work.
To avoid this you can create a loop device before mounting a file:
# mknod -m 0660 /dev/loop8 b 7 8
This creates /dev/loop8. Or create some loop devices at startup:
# echo "options loop max_loop=8" > /etc/modprobe.d/eightloop.conf
Change max_loop=8 to the number of devices you need.
System partition passwords need en_US keymap
If you are using Xorg (which you most likely are, should you not know what that is), use the following command to use US keymap until restart:
# setxkbmap us
Permission denied on NTFS volume
If you cannot modify the filesystem, although permissions seem to be correct, this can be a result of not having NTFS-3G installed, see NTFS.
Corrupted standard volume file system
In case you cannot access your VeraCrypt volume or container anymore, Install testdisk from the official repositories. See more information on CGSecurity page.
$ ./truecrypt -t --filesystem=none /data/data_for_testdisk/truecrypt.dd Enter password for /data/data_for_testdisk/truecrypt.dd: Enter keyfile [none]: Protect hidden volume? (y=Yes/n=No) [No]: Enter system administrator password: $ mount ... truecrypt on /tmp/.truecrypt_aux_mnt1 type fuse.truecrypt (rw,nosuid,nodev,allow_other) $ sudo testdisk /tmp/.truecrypt_aux_mnt1/volume