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LFCS · Question #357

Which of the following are valid dmcrypt modes? (Choose THREE correct answers)

The correct answer is A. XTS B. ESSIV E. LRW. XTS and LRW are valid block cipher modes for dm-crypt, while ESSIV is a valid method for generating initialization vectors in conjunction with cipher modes like CBC.

Submitted by rachelw· Apr 18, 2026Storage Management

Question

Which of the following are valid dmcrypt modes? (Choose THREE correct answers)

Options

  • AXTS
  • BESSIV
  • CGMR
  • DKWG
  • ELRW

How the community answered

(39 responses)
  • A
    90% (35)
  • C
    5% (2)
  • D
    5% (2)

Why each option

XTS and LRW are valid block cipher modes for dm-crypt, while ESSIV is a valid method for generating initialization vectors in conjunction with cipher modes like CBC.

AXTSCorrect

XTS (Xor-Encrypt-Xor with Tweakable Block Cipher) is a widely adopted and robust block cipher mode specifically designed for disk encryption, providing good security and performance.

BESSIVCorrect

ESSIV (Encrypted Salt-Sector Initialization Vector) is a method used with block cipher modes like CBC in dm-crypt to generate unique and unguessable Initialization Vectors for each sector, enhancing security against certain types of attacks.

CGMR

GMR is not a recognized or valid dm-crypt mode.

DKWG

KWG is not a recognized or valid dm-crypt mode.

ELRWCorrect

LRW (Limited-Range Woven) is an older, but still valid, tweakable block cipher mode designed for disk encryption, offering resistance to certain attacks that standard CBC mode might be vulnerable to.

Concept tested: dm-crypt cipher and IV modes

Source: https://gitlab.com/cryptsetup/cryptsetup/-/wikis/DMCrypt

Topics

#dmcrypt#Disk Encryption#Encryption Modes#Storage Security

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