The HAIFA construction (''hash iterative framework'') is a cryptographic structure used in the design of

hash functions A hash function is any function that can be used to map data of arbitrary size to fixed-size values. The values returned by a hash function are called ''hash values'', ''hash codes'', ''digests'', or simply ''hashes''. The values are usually ...

. It is one of the modern alternatives to the

Merkle–Damgård construction In cryptography, the Merkle–Damgård construction or Merkle–Damgård hash function is a method of building collision-resistant cryptographic hash functions from collision-resistant one-way compression functions. Goldwasser, S. and Bellare, M ...

, avoiding its weaknesses like

length extension attack In cryptography and computer security, a length extension attack is a type of attack where an attacker can use Hash(''message1'') and the length of ''message1'' to calculate Hash(''message1'' ‖ ''message2'') for an attacker-controlled ''message2 ...

s. The construction was designed by

Eli Biham Eli Biham ( he, אלי ביהם) is an Israeli cryptographer and cryptanalyst, currently a professor at the Technion - Israel Institute of Technology Computer Science department. Starting from October 2008 and till 2013, Biham was the dean of t ...

and

Orr Dunkelman __INDEX__ Orr Dunkelman ( he, אור דונקלמן) is an Israeli cryptographer and cryptanalyst, currently a professor at the University of Haifa Computer Science department. Dunkelman is a co-director of the Center for Cyber Law & Privacy at ...

in 2007. Three of the 14 second round candidates in the

NIST hash function competition The NIST hash function competition was an open competition held by the US National Institute of Standards and Technology (NIST) to develop a new hash function called SHA-3 to complement the older SHA-1 and SHA-2. The competition was formally an ...

were based on HAIFA constructions (

BLAKE Blake is a surname which originated from Old English. Its derivation is uncertain; it could come from "blac", a nickname for someone who had dark hair or skin, or from "blaac", a nickname for someone with pale hair or skin. Another theory, presuma ...

, SHAvite-3, ECHO). Other hash functions based on it are LAKE, Sarmal, SWIFFTX and HNF-256. The construction of

Skein Skein may refer to: * A flock of geese or ducks in flight * A wound ball of yarn with a centre pull strand; see Hank * A metal piece fitted over the end of a wagon axle, to which the wheel is mounted * Skein (unit), a unit of length used by wea ...

( Unique Block Iteration) is similar to HAIFA.Jean-Philippe Aumasson, Willi Meier, Raphael Phan, Luca Henzen: ''The Hash Function BLAKE'', p. 35 Another alternative construction is the

sponge construction In cryptography, a sponge function or sponge construction is any of a class of algorithms with finite state (computer science), internal state that take an input bit stream of any length and produce an output bit stream of any desired length. Spon ...

References

Cryptographic hash functions Theory of cryptography {{Crypto-stub