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Related-key Impossible Differential Cryptanalysis of Full-round HIGHT
Saeed Rostami
1
, Sadegh Bamohabbat Chafjiri
2
and Seyed Amir Hossein Tabatabaei
3
1
R&D Department, Tehran, Iran
2
Information Systems and Security Lab, Sharif University of Technology, Tehran, Iran
3
Chair for Data Communications Systems, University of Siegen, Siegen, Germany
sae.rostami@gmail.com, bamohabbat@ieee.org, amir.tabatabaei@uni-siegen.de
Keywords:
HIGHT, Lightweight Block Cipher, Related-key, Impossible Differential, Cryptanalysis.
Abstract:
The HIGHT algorithm is a 64-bit block cipher with 128-bit key length, at CHES’06 as a lightweight crypto-
graphic algorithm. In this paper, a new related-key impossible differential attack on the full-round algorithm
is introduced. Our cryptanalysis requires time complexity of 2
127.276
HIGHT evaluations which is slightly
faster than exhaustive search attack. This is the first related-key impossible differential cryptanalysis on the
full-round HIGHT block cipher.
1 INTRODUCTION
Nowadays using cryptographic primitives engaging
lightweight technology is in the point of interest for
the sake of efficiency. The most important applica-
tions lie in smart cards, sensors and, RFIDs where the
processing and memory resources are limited. By us-
ing lightweight technology, it is tried to remove the
problems which are arising from conditions imposed
on the available resources by using low-cost complex-
ity operations. On the other hand, when computa-
tional efficiency is increased security issues should be
taken into account. So, considering a concrete secu-
rity analysis is important in the design process of a
lightweight cryptographic primitive to avoid endan-
gering the desired security level.
The Block cipher HIGHT (high security and light
weight) with 64-block length and 128-key length has
been proposed by Hong et al. for low-cost, low-
power, and, ultra-light implementation (Hong and
et al., 2006). It is an iterative 32-round block cipher
in the shape of generalized Feistel network which is
used as a standard block cipher in South Korea. Sev-
eral attacks on the HIGHT have shown some potential
weaknesses of the reduced-round algorithm. The se-
curity strength of the algorithm against linear attack
(Matsui, 1994) and differential cryptanalysis (Biham
and Shamir, 1991) has been considered by its design-
ers (Hong and et al., 2006). In (Ozen et al., 2009)
the saturation attack (Lucks, 2002) on 16-round al-
gorithm using 12-round characteristic was presented
which has been improved in (Zhang et al., 2009) to
target 22-round HIGHT. Impossible differential and
related-key impossible differential attacks (Biham
et al., 2005; Biham et al., 1999) on the HIGHT are
covering more rounds (Hong and et al., 2006; Lu,
2007; Ozen et al., 2009). Till now with the best
knowledge of the authors, the only attacks which tar-
get the full-round HIGHT are related-key rectangle
attack (Hong et al., 2011) and biclique cryptanalysis
(Hong et al., 2012). Although their time complexity
(Hong et al., 2011) is almost the the same as com-
plexity of our attack, our attack is the first related-
key impossible differential attack on the full round
HIGHT so far. In this paper, we propose a related-
key impossible differential cryptanalysis on the full-
round HIGHT with the complexity less than exhaus-
tive search attack. A comparison between the re-
sult of our proposed attack and previously introduced
related-key impossible differential attacks is provided
in Table 1.
We mount our attack on the full-round algorithm
by using a 24-round impossible differential character-
istic. The main advantage of our approach in compar-
ison with attacks proposed in (Lu, 2007) and (Ozen
et al., 2009) is to use different differential characteris-
tics which enables us to attack on the algorithm with
one more round. The rest of this paper is organized
as follows. In Section 2, the block cipher HIGHT is
described. Extracting a new 24-round impossible dif-
ferential characteristic will be given in Section 3. In
Section 4, the full-round attack scenario and the com-
plexity discussion will be given which concludes the
paper.
537
Rostami S., Bamohabbat Chafjiri S. and Amir Hossein Tabatabaei S..
Related-key Impossible Differential Cryptanalysis of Full-round HIGHT.
DOI: 10.5220/0004528805370542
In Proceedings of the 10th International Conference on Security and Cryptography (SECRYPT-2013), pages 537-542
ISBN: 978-989-8565-73-0
Copyright
c
2013 SCITEPRESS (Science and Technology Publications, Lda.)