Abstract
This work deals with the security and efficiency of type-I and type-II generalized Feistel networks (GFNs) with 4 lines. We propose to instantiate the GFNs with double SP-functions (substitutionpermutation layer followed by another substitution-permutation layer) instead of single SP-functions (one substitution-permutation layer). We provide tight lower bounds on the number of differentially and linearly active functions and S-boxes in such ciphers. Based on these bounds, we show that the instantiation with double SP-functions using MDS diffusion has a proportion of differentially and linearly active S-boxes by up to 33% and 50% higher than that with single SP-functions for type-I and type-11 GENs, respectively. This opens up the possibility of designing more efficient block ciphers based on GFN structure. Note that type-1 and type-II GFNs are the only non-contracting OFNs with 4 lines under a reasonable definition of a GFN.
| Original language | English |
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| Title of host publication | Information Security and Privacy. Proceedings |
| Publisher | Springer |
| Publication date | 2011 |
| Pages | 106-119 |
| ISBN (Print) | 978-3-642-22496-6 |
| ISBN (Electronic) | 978-3-642-22497-3 |
| Publication status | Published - 2011 |
| Externally published | Yes |
| Event | 16th Australasian Conference on Information Security and Privacy - Melbourne, Australia Duration: 11 Jul 2011 → 13 Jul 2011 Conference number: 16 |
Conference
| Conference | 16th Australasian Conference on Information Security and Privacy |
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| Number | 16 |
| Country/Territory | Australia |
| City | Melbourne |
| Period | 11/07/2011 → 13/07/2011 |
| Series | Lecture Notes in Computer Science |
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| Volume | 6812 |
| ISSN | 0302-9743 |