Related Directory Categories
- Ciphers (32)
- Mercy (25)
- Sisters of Mercy, The (19)
- WWF No Mercy (13)
- Divine Mercy (12)
- Tender Mercies (6)
- Reviews and Previews (6)
- MercyMe (4)
- Sisters of Mercy (4)
- Detroit Mercy (4)
Sources
Help build the largest human-edited directory on the web.
Submit a site - Become an editor
Wikipedia. Licensed under the GNU Free Documentation License.
Are you an expert in this subject? Join the discussion and share your knowledge at Wikipedia.org.
Mercy (cipher)
From Wikipedia, the free encyclopedia
| Mercy | |
| General | |
|---|---|
| Designer(s): | Paul Crowley |
| First published: | April 2000[1] |
| Derived from: | WAKE |
| Cipher detail | |
| Key size(s): | 128 bits |
| Block size(s): | 4096 bits |
| Structure: | Feistel network |
| Rounds: | 6 |
| Best public cryptanalysis | |
| Scott Fluhrer's differential attack breaks the cipher.[2] | |
In cryptography, Mercy is a tweakable block cipher designed by Paul Crowley for disk encryption.
The block size is 4096 bits—unusually large for a block cipher, but a standard disk sector size. Mercy uses a 128-bit secret key, along with a 128-bit non-secret tweak for each block. In disk encryption, the sector number would be used as a tweak. Mercy uses a 6-round Feistel network structure with partial key whitening. The round function uses a key-dependent state machine which borrows some structure from the stream cipher WAKE, with key-dependent S-boxes based on the Nyberg S-boxes also used in AES.
Scott Fluhrer has discovered a differential attack that works against the full 6 rounds of Mercy. This attack can even be extended to a seven-round variant.[2]
- ^ Paul Crowley, Mercy: A fast large block cipher for disk sector encryption. In Bruce Schneier, editor, Fast Software Encryption: 7th International Workshop, volume 1978 of Lecture Notes in Computer Science, pages 49-63, New York, USA, April 2000. Springer-Verlag.
- ^ a b Scott Fluhrer (April 2, 2006). "Cryptanalysis of the Mercy Block Cipher" (PostScript). Fast Software Encryption Workshop 2001, Royal Park Hotel Nikko, Yokohama, Japan: Cisco Systems, Inc.. Retrieved on 2006-12-15.
 |
This cryptography-related article is a stub. You can help Wikipedia by expanding it. |