A lightweight 256-bit hash function for hardware and low-end devices: Lesamnta-LW

Abstract

This paper proposes a new lightweight 256-bit hash function Lesamnta-LW with claimed security levels of at least 2120 with respect to collision, preimage, and second preimage attacks. We adopt the Merkle-Damgård domain extension; the compression function is constructed from a dedicated AES-based block cipher using the LW1 mode, for which a security reduction can be proven. In terms of lightweight implementations, Lesamnta-LW offers a competitive advantage over other 256-bit hash functions. Our size-optimized hardware implementation of Lesamnta-LW requires only 8.24 Kgates on 90 nm technology. Our software implementation of Lesamnta-LW requires only 50 bytes of RAM and runs fast on short messages on 8-bit CPUs. © 2011 Springer-Verlag.