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The main purpose of block ciphers is to ensure data confidentiality, integrity and robustness against security attacks. Nevertheless, several ciphers also try to be efficient in encryption and decryption phases, have a small energy consumption and/or small memory footprint. These ciphers are usually optimized for certain software or hardware platforms. In this work, we analyze lightweight and classic block ciphers. Further, we implement an application which employs 20 current software-oriented block ciphers and benchmark them on a smartphone. The experimental results and the performance evaluation of ciphers are presented. Moreover, we compare the performance of two forms of implementation by native JAVA cryptography APIs and by an external cryptography provider. In addition, we measure the current consumption of the selected block ciphers on a smartphone. [ABSTRACT FROM AUTHOR]

In this work, we present a practical passive attack on SASI, an ultra-lightweight mutual authentication protocol for RFID. This attack can be used to reveal with overwhelming probability the secret ID of the prover by eavesdropping about 217 authentications. The result dismantles SASI and, more generally, provides a new approach that threatens ultra-lightweight authentication protocols. [ABSTRACT FROM AUTHOR]

PRESENT is a hardware-oriented block cipher suitable for resource constrained environment. In this paper we analyze PRESENT by the multidimensional linear cryptanalysis method. We claim that our attack can recover the 80-bit secret key of PRESENT up to 25 rounds out of 31 rounds with around 262.4 data complexity. Furthermore, we showed that the 26-round version of PRESENT can be attacked faster than key exhaustive search with the 264 data complexity by an advanced key search technique. Our results are superior to all the previous attacks. We demonstrate our result by performing the linear attacks on reduced variants of PRESENT. Our results exemplify that the performance of the multidimensional linear attack is superior compared to the classical linear attack. [ABSTRACT FROM AUTHOR]

The former Soviet encryption algorithm GOST 28147-89 has been standardized by the Russian standardization agency in 1989 and extensive security analysis has been done since. So far no weaknesses have been found and GOST is currently under discussion for ISO standardization. Contrary to the cryptographic properties, there has not been much interest in the implementation properties of GOST, though its Feistel structure and the operations of its round function are well-suited for hardware implementations. Our post-synthesis figures for an ASIC implementation of GOST with a key-length of 256 bits require only 800 GE, which makes this implementation well suitable for low-cost passive RFID-tags. As a further optimization, using one carefully selected S-box instead of 8 different ones -which is still fully compliant with the standard specifications!- the area requirement can be reduced to 651 GE. [ABSTRACT FROM AUTHOR]

A new 128-bit block cipher, TWIS is proposed. It uses key size of 128-bits. The design targets to software environment for resource constrained applications. It is inspired from existing block cipher, CLEFIA. Although the proposed design uses less resources as compared to CLEFIA, it compares favorably with CLEFIA in terms of security provided. [ABSTRACT FROM AUTHOR]

The limited computational resources available in RFID tags implied an intensive search for lightweight authentication protocols in the last years. The most promising suggestions were those of the HB-familiy (HB  + , HB #, TrustedHB, ...) initially introduced by Juels and Weis, which are provably secure (via reduction to the Learning Parity with Noise (LPN) problem) against passive and some kinds of active attacks. Their main drawbacks are large amounts of communicated bits and the fact that all known HB-type protocols have been proven to be insecure with respect to certain types of active attacks. As a possible alternative, authentication protocols based on choosing random elements from L secret linear n-dimensional subspaces of GF(2)n + k (so called CKK-protocols) were introduced by Cichoń, Klonowski, and Kutyłowski. These protocols are special cases of (linear) (n,k,L)-protocols which we investigate in this paper. We present several active and passive attacks against (n,k,L)-protocols and propose (n,k,L) + + -protocols which we can prove to be secure against certain types of active attacks. We obtain some evidence that the security of (n,k,L)-protocols can be reduced to the hardness of the learning unions of linear subspaces (LULS) problem. We then present a learning algorithm for LULS based on solving overdefined systems of degree L in Ln variables. Under the hardness assumption that LULS-problems cannot be solved significantly faster, linear (n,k,L)-protocols (with properly chosen n,k,L) could be interesting for practical applications. [ABSTRACT FROM AUTHOR]

The use of concatenated Schnorr signatures [Sch91] for the hierarchical delegation of public keys is a well-known technique. In this paper we carry out a thorough analysis of the identity-based signature scheme that this technique yields. The resulting scheme is of interest since it is intuitive, simple and does not require pairings. We prove that the scheme is secure against existential forgery on adaptive chosen message and adaptive identity attacks using a variant of the Forking Lemma [PS00]. The security is proven in the Random Oracle Model under the discrete logarithm assumption. Next, we provide an estimation of its performance, including a comparison with the state of the art on identity-based signatures. We draw the conclusion that the Schnorr-like identity-based signature scheme is arguably the most efficient such scheme known to date. [ABSTRACT FROM AUTHOR]

At Pervasive 2008, Cichon, Klonowski, Kutylowski proposed a family of shared-key authentication protocols ( ]> ). Small computational and communication cost, together with possibility of efficient hardware implementation makes ]> attractive for low-cost devices such as RFID tags. In this paper we present a couple of attacks on ]> protocols, both passive and active. [ABSTRACT FROM AUTHOR]