XTEA is a 64-round block cipher with a 64-bit block size and a 128-bit user key, which was designed as a short C program that would run safely on most computers. In this paper, we present a related-key rectangle attack on a series of inner 36 rounds of XTEA without making a weak key assumption, and a related-key rectangle attack on the first 36 rounds of XTEA under certain weak key assumptions. These are better than any previously published cryptanalytic results on XTEA in terms of the numbers of attacked rounds.

Related-key rectangle attack on 36 rounds of the XTEA block cipher

A method and system for detecting fraudulent data update of databases connected to a plurality of distributed computers in which a monitor computer connected via a network to the distributed computers detects fraudulent data update. The monitor computer collects initial data of the databases of the distributed computers via the network to generate parities for data at same storage fields and store them in a monitor database. Each time the databases connected to the distributed computers are updated, a parity update unit of the monitor computer generates new parities from data before and after the update and old parities and replaces the old parities stored in the monitor database by the new parities. At an auditing time, the monitor computer collects latest data of the distributed databases and generates parities which are compared with the corresponding parities already stored in the monitor database to detect an inconsistency of both parities.

Method and system for detecting fraudulent data update

In this paper, we propose a multilevel database encryption system with subkeys. This new system is called the record-oriented cryptosystem which encrypts each record with different field-subkeys according to a security class of the data element. Each field is decrypted individually by the field-subkeys of which security class is higher than or equal to that of the encrypted field-subkeys. This system is based on the Chinese Remainder Theorem. Our scheme can protect the finest level of granularity such as relation level, attribute level, tuple level, or data element level in the relational database model.

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Multilevel secure database encryption with subkeys

We propose an efficient public key encryption scheme which is key-dependent message secure against chosen ciphertext attacks (KDM-CCA) with respect to affine functions based on the decisional composite residuosity assumption. Technically, we achieve KDM-CCA security by enhancing a chosen ciphertext secure scheme based on the high entropy hash proof system with three tools: a key-dependent message encoding, an entropy filter and an authenticated encryption secure against related-key attacks.

KDM-CCA security from RKA secure authenticated encryption

The invention features a public key cryptography method based on the discrete logarithm which computes a value Gkmodp. Two solutions are proposed to reduce the number of multiplications, one consisting in generating 'hollow' k exponents with few bits of value 1, but of sufficient length to maintain the total security of the system, and the other consisting in parallel g power computations in while combining the exponents with each other so as not to repeat the same power computations twice for a given exponent, The invention is useful for generating digital signatures, for authentication, for encryption.

Public key cryptography method

https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2114&context=infopapers

Refereed paper: Database authentication revisited

Threshold cryptosystems.- Authentication codes with perfect protection.- Practical proven secure authentication with arbitration.- Authentication codes under impersonation attack.- Cumulative arrays and geometric secret sharing schemes.- Nonperfect secret sharing schemes.- A construction of practical secret sharing schemes using linear block codes.- HAVAL - A one-way hashing algorithm with variable length of output (extended abstract).- On the power of memory in the design of collision resistant hash functions.- A practical digital multisignature scheme based on discrete logarithms (extended abstract).- Group-oriented undeniable signature schemes without the assistance of a mutually trusted party.- Highly nonlinear 0-1 balanced boolean functions satisfying strict avalanche criterion (extended abstract).- Linear nonequivalence versus nonlinearity.- Constructing large cryptographically strong S-boxes.- Nonasymptotic estimates of information protection efficiency for the wire-tap channel concept.- Cryptanalysis of LOKI 91.- Cryptanalysis of summation generator.- Secure addition sequence and its applications on the server-aided secret computation protocols.- Subliminal channels for signature transfer and their application to signature distribution schemes.- A practical secret voting scheme for large scale elections.- Privacy for multi-party protocols.- New protocols for electronic money.- Modelling and analyzing cryptographic protocols using Petri nets.- On verifiable implicit asking protocols for RSA computation.- Modified Maurer-Yacobi's scheme and its applications.- The vulnerability of geometric sequences based on fields of odd characteristic.- A fast cryptographic checksum algorithm based on stream ciphers.- An approach to the initial state reconstruction of a clock-controlled shift register based on a novel distance measure.- Construction of m-ary de Bruijn sequences (extended abstract).- Information technology security standards - An Australian perspective.- Non-interactive generation of shared pseudorandom sequences.- A generalized description of DES-based and Benes-based permutationgenerators.- Prime generation with the Demytko-Miller-Trbovich algorithm.- Constructions of feebly-one-way families of permutations.- On bit correlations among preimages of "Many to one" One-way functions.- The fast cascade exponentiation algorithm and its applications on cryptography.- The design of a conference key distribution system.- Remarks on "The design of a Conference Key Distribution System".- Public-key cryptosystem based on the discrete logarithm problem.- Elliptic curves over F p suitable for cryptosystems.- The probability Distribution of the Diffie-Hellman Key.- A modular exponentiation unit based on systolic arrays.- A comparison of key distribution patterns constructed from circle geometries.- A block cipher method using combinations of different methods under the control of the user key.- An attack on two hash functions by Zheng-Matsumoto-Imai.- Primality testing with Lucas functions.

Advances in Cryptology - AUSCRYPT '92: Workshop on the Theory and Application of Cryptographic Techniques, Gold Coast, Queensland, Australia, December 13-15, 1992 Proceedings

Yuliang Zheng

Papers

Refereed paper: Database authentication revisited

Advances in Cryptology - AUSCRYPT '92: Workshop on the Theory and Application of Cryptographic Techniques, Gold Coast, Queensland, Australia, December 13-15, 1992 Proceedings

Kuperee: An Approach to Authentication using Public Keys