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LUKS: Difference between revisions

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See [[Archwiki: dm-crypt/Device encryption]].
See [[Archwiki: dm-crypt/Device encryption]].


===Encrypting a device===
===Install cryptsetup===
* Setup encryption
<pre>
<pre>
cryptsetup -v --type luks1 --cipher aes-xts-plain64 --key-size 512 --hash sha512 \
sudo apt install cryptsetup
          --iter-time 5000 --use-urandom --verify-passphrase luksFormat <device>
</pre>
</pre>


* Open encrypted drive
===Encrypting a device===
<pre>
<syntaxhighlight lang="bash">
cryptsetup open <device> <name>
# Examples
</pre>
DEVICE=/dev/sda
NAME=arr1
 
# Setup encryption
cryptsetup --type luks2 -v luksFormat "${DEVICE}"
 
# Open encrypted drive to /dev/mapper/$NAME
cryptsetup open "${DEVICE}" "${NAME}"
 
# Create a partition
mkfs.btrfs /dev/mapper/${NAME}
 
# Create a mountpoint and mount
mkdir -p /media/${NAME}
mount -t btrfs /dev/mapper/${NAME} /media/${NAME}
 
# Fill the drive to overwrite any existing raw data (optional)
dd if=/dev/zero of=/media/$NAME/file status=progress
</syntaxhighlight>


* Create a partition
===Mounting===
<pre>
<syntaxhighlight lang="bash">
mkfs.fstype /dev/mapper/<name>
# Open the encrypted drive
# E.g.
cryptsetup open "${DEVICE}" "${NAME}"
# mkfs.ext4 /dev/mapper/luksdrive1
# Mount your partition
</pre>
mount -t btrfs /dev/mapper/${NAME} "${MOUNT_LOCATION}"
</syntaxhighlight>


* Securely wipe the unused portion of the drive
===Unmounting===
** Do this to prevent cryptographic attacks and to overwrite existing data on the drive
<syntaxhighlight lang="bash">
<pre>
# Unmount your partition
dd if=/dev/zero of=<file_somewhere> status=progress
umount "${MOUNT_LOCATION}"
# Delete the file afterwards
# Close the decrypted drive
</pre>
cryptsetup close ${NAME}
</syntaxhighlight>


===Encrpytion Options===


;Notes
* You can see defaults using <code>cryptsetup --help</code>.
* You can see defaults using <code>cryptsetup --help</code>.
* <code>--type</code> [https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption#Encryption_options_with_dm-crypt options]
* <code>--type</code> [https://wiki.archlinux.org/index.php/Dm-crypt/Device_encryption#Encryption_options_with_dm-crypt options]
** <code>luks</code> defaults to <code>luks1</code> on cryptsetup < 2.1.0, <code>luks2</code> on cryptsetup >= 2.1.0
** <code>luks</code> defaults to <code>luks1</code> on cryptsetup < 2.1.0, <code>luks2</code> on cryptsetup >= 2.1.0
** <code>luks1</code> is the standard version of LUKS.
** <code>luks1</code> is the old version of LUKS.
** <code>luks2</code> is a new version released in Dec 2017. Older versions of Grub (before 2.06 or June 2020) do not support booting from LUKS2.
** <code>luks2</code> is the current version released in Dec 2017. Older versions of Grub (before 2.06 or June 2020) do not support booting from LUKS2.
** <code>plain</code> is dm-crypt plain mode. Avoid this unless you know what you're doing.
** <code>plain</code> is dm-crypt plain mode. Avoid this unless you know what you're doing.
** <code>loopaes</code> Avoid this as well.
** <code>loopaes</code> Avoid this as well.
** <code>tcrypt</code> Use this for mounting older truecrypt volumes.
** <code>tcrypt</code> Use this for mounting older truecrypt volumes.
* <code>--iter-time</code> dynamically determines the number of iterations used to hash your password. The number of iterations is determined when creating the luks key. E.g. <code>5000</code> means hash for 5 seconds worth of iterations on your particular CPU. You can see the number of iterations for each key with <code>cryptsetup luksDump &lt;device&gt;</code>.


{{ hidden | defaults |
{{ hidden | defaults |
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</pre>
</pre>
}}
}}
===Mounting===
<pre>
# Open the encrypted drive
cryptsetup open <device> <name>
# Mount your partition
mount -t <fstype> /dev/mapper/<name> <mountlocation>
</pre>
===Unmounting===
<pre>
# Unmount your partition
umount <mountlocation>
# Close the decrypted drive
cryptsetup close <name>
</pre>


==Benchmark==
==Benchmark==
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</pre>
</pre>


{{ hidden | Example Output |
{{ hidden | Example Output (i7-12700K) |
<pre>
<pre>
# Tests are approximate using memory only (no storage IO).
# Tests are approximate using memory only (no storage IO).
PBKDF2-sha1      1213629 iterations per second for 256-bit key
PBKDF2-sha1      3057072 iterations per second for 256-bit key
PBKDF2-sha256    1524093 iterations per second for 256-bit key
PBKDF2-sha256    6452775 iterations per second for 256-bit key
PBKDF2-sha512    1082121 iterations per second for 256-bit key
PBKDF2-sha512    2432890 iterations per second for 256-bit key
PBKDF2-ripemd160 648069 iterations per second for 256-bit key
PBKDF2-ripemd160 1289761 iterations per second for 256-bit key
PBKDF2-whirlpool 421453 iterations per second for 256-bit key
PBKDF2-whirlpool 1148495 iterations per second for 256-bit key
argon2i       4 iterations, 875179 memory, 4 parallel threads (CPUs) for 256-bit key (requested 2000 ms time)
argon2i     13 iterations, 1048576 memory, 4 parallel threads (CPUs) for 256-bit key (requested 2000 ms time)
argon2id     4 iterations, 889195 memory, 4 parallel threads (CPUs) for 256-bit key (requested 2000 ms time)
argon2id     13 iterations, 1048576 memory, 4 parallel threads (CPUs) for 256-bit key (requested 2000 ms time)
#    Algorithm |      Key |      Encryption |      Decryption
#    Algorithm |      Key |      Encryption |      Decryption
         aes-cbc        128b       542.7 MiB/s      2192.7 MiB/s
         aes-cbc        128b     1976.6 MiB/s      7781.1 MiB/s
     serpent-cbc        128b       67.3 MiB/s      459.9 MiB/s
     serpent-cbc        128b       136.8 MiB/s      993.0 MiB/s
     twofish-cbc        128b      140.6 MiB/s      285.8 MiB/s
     twofish-cbc        128b      291.3 MiB/s      646.8 MiB/s
         aes-cbc        256b       405.3 MiB/s      1701.8 MiB/s
         aes-cbc        256b     1507.6 MiB/s      6406.3 MiB/s
     serpent-cbc        256b       71.6 MiB/s      459.5 MiB/s
     serpent-cbc        256b       138.2 MiB/s      984.0 MiB/s
     twofish-cbc        256b      146.6 MiB/s      287.1 MiB/s
     twofish-cbc        256b      295.3 MiB/s      647.1 MiB/s
         aes-xts        256b      1421.6 MiB/s      1449.2 MiB/s
         aes-xts        256b      6021.9 MiB/s      5909.9 MiB/s
     serpent-xts        256b      455.9 MiB/s      444.0 MiB/s
     serpent-xts        256b      855.7 MiB/s      887.4 MiB/s
     twofish-xts        256b      284.2 MiB/s      286.3 MiB/s
     twofish-xts        256b      597.8 MiB/s      608.0 MiB/s
         aes-xts        512b      1187.2 MiB/s      1177.9 MiB/s
         aes-xts        512b      5521.2 MiB/s      5505.7 MiB/s
     serpent-xts        512b      454.7 MiB/s      446.1 MiB/s
     serpent-xts        512b      870.2 MiB/s      897.9 MiB/s
     twofish-xts        512b      284.9 MiB/s      286.5 MiB/s
     twofish-xts        512b      602.9 MiB/s      607.1 MiB/s
</pre>
</pre>
}}
}}


==Adiantum==
==Adiantum==
If you're running a device which does not support AES instructions (e.g. Raspberry Pi), you may be interested in Adiantum<ref name="adiantum">Google Blog: Introducing Adiantum: Encryption for the Next Billion Users [https://security.googleblog.com/2019/02/introducing-adiantum-encryption-for.html https://security.googleblog.com/2019/02/introducing-adiantum-encryption-for.html]</ref>.   
If you're running a device which does not support hardware accelerated AES instructions (e.g. Raspberry Pi), you may be interested in Adiantum<ref name="adiantum">Google Blog: Introducing Adiantum: Encryption for the Next Billion Users [https://security.googleblog.com/2019/02/introducing-adiantum-encryption-for.html https://security.googleblog.com/2019/02/introducing-adiantum-encryption-for.html]</ref>.   
Adiantum
Adiantum is an encryption mode by Google which uses ChaCha12 for block encryption.
It is included in Linux kernel v5.0.


;Creation
;Creation
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;Benchmark<ref>[https://www.reddit.com/r/crypto/comments/b3we04/aesadiantum_new_mode_in_linux_kernel_5/ https://www.reddit.com/r/crypto/comments/b3we04/aesadiantum_new_mode_in_linux_kernel_5/]</ref>
;Benchmark<ref>[https://www.reddit.com/r/crypto/comments/b3we04/aesadiantum_new_mode_in_linux_kernel_5/ https://www.reddit.com/r/crypto/comments/b3we04/aesadiantum_new_mode_in_linux_kernel_5/]</ref>
<pre>
<pre>
cryptsetup benchmark -c xchacha12,aes-adiantum -s 512
cryptsetup benchmark -c xchacha12,aes-adiantum
</pre>
</pre>


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}
}


mount_luks ext4 /dev/disk/by-id/<drive> lukscrypt1 /media/lukscrypt1
mount_luks btrfs /dev/disk/by-id/<drive> lukscrypt1 /media/lukscrypt1
</syntaxhighlight>
</syntaxhighlight>
}}
}}
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==Resources==
==Resources==
* [https://www.cyberciti.biz/hardware/howto-linux-hard-disk-encryption-with-luks-cryptsetup-command/ nixCraft How To Linux Hard Disk Encryption With LUKS]
* [https://www.cyberciti.biz/hardware/howto-linux-hard-disk-encryption-with-luks-cryptsetup-command/ nixCraft How To Linux Hard Disk Encryption With LUKS]
==References==
Retrieved from "https://wiki.davidl.me/view/LUKS"