 The Feistel function of the Cryptomeria cipher. | |
| General | |
|---|---|
| Designers | 4C Entity |
| First published | 2003 |
| Derived from | DES |
| Related to | CSS |
| Cipher detail | |
| Key sizes | 56 bits |
| Block sizes | 64 bits |
| Structure | Feistel network |
| Rounds | 10 |
| Best public cryptanalysis | |
| A boomerang attack breaks all 10 rounds in 248 time with known S-box, or 253.5 with an unknown S-box, using 244 adaptively chosen plaintexts/ciphertexts. [1] | |
The Cryptomeria cipher, also called C2, is a proprietary block cipher defined and licensed by the 4C Entity. It is the successor to CSS algorithm (used for DVD-Video) and was designed for the CPRM/CPPM digital rights management scheme which are used by DRM-restricted Secure Digital cards and DVD-Audio discs.
- ^ Borghoff, Julia; Knudsen, Lars R.; Leander, Gregor; Matusiewicz, Krystian (2009). "Cryptanalysis of C2". Advances in Cryptology - CRYPTO 2009. Lecture Notes in Computer Science. Vol. 5677. Berlin, Heidelberg: Springer Berlin Heidelberg. pp. 250–266. doi:10.1007/978-3-642-03356-8_15. ISBN 978-3-642-03355-1. ISSN 0302-9743.