MASH-1 is a hash function

Hash function

A hash function is any algorithm or subroutine that maps large data sets to smaller data sets, called keys. For example, a single integer can serve as an index to an array...

 based on modular arithmetic

Modular arithmetic

In mathematics, modular arithmetic is a system of arithmetic for integers, where numbers "wrap around" after they reach a certain value—the modulus....

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History

Despite many proposals, few hash functions based on modular arithmetic have withstood attack, and most that have tend to be relatively inefficient. MASH-1 evolved from a long line of related proposals successively broken and repaired.

Description

MASH-1 involves use of an RSA-like modulus M, whose bitlength affects the security. M should be difficult to factor

Factorization

In mathematics, factorization or factoring is the decomposition of an object into a product of other objects, or factors, which when multiplied together give the original...

, and for M of unknown factorization, the security is based in part on the difficulty of extracting modular roots. M also determines the block size for processing messages.

MASH-2

There is a new version of the algorithm called MASH-2 with a different exponent. The original is replaced by .