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On-Line Authenticated Encryption (OAE) combines privacy with data integrity and is on-line computable. Most block cipher-based schemes for Authenticated Encryption can be run on-line and are provably secure against nonce-respecting adversaries. But they fail badly for more general adversaries. This is not a theoretical observation only – in practice, the(More)
We provide the first proof of security for Tandem-DM, one of the oldest and most well-known constructions for turning a block cipher with n-bit block length and 2n-bit key length into a 2n-bit cryptographic hash function. We prove, that when Tandem-DM is instantiated with AES-256, block length 128 bits and key length 256 bits, any adversary that asks less(More)
The GOST block cipher was developed in the 1970s and is a standard currently used in the Russian government. In this paper we present a new attack on the GOST block cipher that uses only 2 7.5 chosen plaintexts and ciphertexts and runs in time 2 7.5. Due to the very low complexity we state that our attack is memoryless and runs in nearly zero time. In this(More)
We provide the first proof of security for Abreast-DM, one of the oldest and most well-known constructions for turning a block cipher with n-bit block length and 2n-bit key length into a 2n-bit cryptographic hash function. In particular, we prove that when Abreast-DM is instantiated with AES-256, i.e. a block cipher with 128-bit block length and 256-bit key(More)
In this note we give an overview on the current state of the SHA-3 candidates. First, we classify all publicly known candidates and, second, we outline and summarize the performance data as given in the candidates documentation for 64-bit and 32-bit implementations. We define performance classes and classify the hash algorithms. Note, that this article will(More)
ARIA [4] is a block cipher proposed at ICISC'03. Its design is very similar to the advanced encryption standard (AES). The authors propose that on 32-bit processors, the encryption speed is at least 70% of that of the AES. They claim to offer a higher security level than AES. In this paper we present two attacks of reduced round ARIA which shows some(More)
At Crypto 2005, Coron et al. introduced a formalism to study the presence or absence of structural flaws in iterated hash functions: If one cannot differentiate a hash function using ideal primitives from a random oracle, it is considered structurally sound, while the ability to differentiate it from a random oracle indicates a structural weakness. This(More)