RIPEMD (RIPE Message Digest) is a family of

cryptographic hash function A cryptographic hash function (CHF) is a hash algorithm (a map of an arbitrary binary string to a binary string with fixed size of n bits) that has special properties desirable for cryptography: * the probability of a particular n-bit output re ...

s developed in 1992 (the original RIPEMD) and 1996 (other variants). There are five functions in the family: RIPEMD, RIPEMD-128, RIPEMD-160, RIPEMD-256, and RIPEMD-320, of which RIPEMD-160 is the most common. The original RIPEMD, as well as RIPEMD-128, is not considered secure because 128-bit result is too small and also (for the original RIPEMD) because of design weaknesses. The 256- and 320-bit versions of RIPEMD provide the same level of security as RIPEMD-128 and RIPEMD-160, respectively; they are designed for applications where the security level is sufficient but longer hash result is necessary. While RIPEMD functions are less popular than

SHA-1 In cryptography, SHA-1 (Secure Hash Algorithm 1) is a cryptographically broken but still widely used hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecima ...

and

SHA-2 SHA-2 (Secure Hash Algorithm 2) is a set of cryptographic hash functions designed by the United States National Security Agency (NSA) and first published in 2001. They are built using the Merkle–Damgård construction, from a one-way compression ...

, they are used, among others, in

Bitcoin Bitcoin ( abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer bitcoin network. Bitcoin transactions are verified by network nodes through cryptography and recorded in a public distr ...

and other

cryptocurrencies A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank A bank is a financial i ...

based on Bitcoin.

History

The original RIPEMD function was designed in the framework of the EU project RIPE (

RACE Race, RACE or "The Race" may refer to: * Race (biology), an informal taxonomic classification within a species, generally within a sub-species * Race (human categorization), classification of humans into groups based on physical traits, and/or s ...

Integrity Primitives Evaluation) in 1992. Its design was based on the

MD4 The MD4 Message-Digest Algorithm is a cryptographic hash function developed by Ronald Rivest in 1990. The digest length is 128 bits. The algorithm has influenced later designs, such as the MD5, SHA-1 and RIPEMD algorithms. The initialism "MD" s ...

hash function. In 1996, in response to security weaknesses found in the original RIPEMD,

Hans Dobbertin Hans Dobbertin (April 17, 1952 – February 2, 2006) was a German cryptographer who is best known for his work on cryptanalysis of the MD4, MD5, and original RIPEMD hash functions, and for his part in the design of the new version of the RIPEMD ...

, Antoon Bosselaers and

Bart Preneel Bart Preneel (born 15 October 1963 in Leuven, Belgium) is a Flemish cryptographer and cryptanalyst. He is a professor at Katholieke Universiteit Leuven, in the COSIC group. He was the president of the International Association for Cryptologic R ...

at the

COSIC The Computer Security and Industrial Cryptography research group, commonly called COSIC, is a research group at the Department of Electrical Engineering of KU Leuven, which is headed by Bart Preneel. Research Research and expertise in digital s ...

research group at the

Katholieke Universiteit Leuven KU Leuven (or Katholieke Universiteit Leuven) is a Catholic research university in the city of Leuven, Belgium. It conducts teaching, research, and services in computer science, engineering, natural sciences, theology, humanities, medicine, l ...

Leuven, Belgium Leuven (, ) or Louvain (, , ; german: link=no, Löwen ) is the capital and largest city of the province of Flemish Brabant in the Flemish Region of Belgium. It is located about east of Brussels. The municipality itself comprises the historic c ...

published four strengthened variants: RIPEMD-128, RIPEMD-160, RIPEMD-256, and RIPEMD-320. In August 2004, a collision was reported for the original RIPEMD. This does not apply to RIPEMD-160.

RIPEMD-160 hashes

The 160-bit RIPEMD-160 hashes (also termed RIPE ''message digests'') are typically represented as 40-digit

hexadecimal In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of 16. Unlike the decimal system representing numbers using 10 symbols, hexa ...

numbers. The following demonstrates a 43-byte

ASCII ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because of ...

input and the corresponding RIPEMD-160 hash: RIPEMD-160("The quick brown fox jumps over the lazy og") = 37f332f68db77bd9d7edd4969571ad671cf9dd3b RIPEMD-160 behaves with the desired

avalanche effect In cryptography, the avalanche effect is the desirable property of cryptographic algorithms, typically block ciphers and cryptographic hash functions, wherein if an input is changed slightly (for example, flipping a single bit), the output changes ...

of cryptographic hash functions (small changes, e.g. changing to , result in a completely different hash): RIPEMD-160("The quick brown fox jumps over the lazy og") = 132072df690933835eb8b6ad0b77e7b6f14acad7 The hash of a zero-length string is: RIPEMD-160("") = 9c1185a5c5e9fc54612808977ee8f548b2258d31

Implementations

Below is a list of cryptography libraries that support RIPEMD (specifically RIPEMD-160): * Botan *

Bouncy Castle Bounce or The Bounce may refer to: * Deflection (physics), the event where an object collides with and bounces against a plane surface Books * Mr. Bounce, a character from the Mr. Men series of children's books Broadcasting, film and TV * ''B ...

Cryptlib cryptlib is an open-source cross-platform software security toolkit library. It is distributed under the Sleepycat License, a free software license compatible with the GNU General Public License. Alternatively, cryptlib is available under a pr ...

Crypto++ Crypto++ (also known as CryptoPP, libcrypto++, and libcryptopp) is a free and open-source C++ class library of cryptographic algorithms and schemes written by Wei Dai. Crypto++ has been widely used in academia, student projects, open-source, and no ...

Libgcrypt Libgcrypt is a cryptography library developed as a separated module of GnuPG. It can also be used independently of GnuPG, but depends on its error-reporting library Libgpg-error. It provides functions for all fundamental cryptographic building blo ...

mbed TLS Mbed TLS (previously PolarSSL) is an implementation of the TLS and SSL protocols and the respective cryptographic algorithms and support code required. It is distributed under the Apache License version 2.0. Stated on the website is that Mbed ...

Nettle {{redirect, Nettle Nettle refers to plants with stinging hairs, particularly those of the genus ''Urtica''. It can also refer to plants which resemble ''Urtica'' species in appearance but do not have stinging hairs. Plants called "nettle" include ...

OpenSSL OpenSSL is a software library for applications that provide secure communications over computer networks against eavesdropping or need to identify the party at the other end. It is widely used by Internet servers, including the majority of HTT ...

wolfSSL wolfSSL is a small, portable, embedded SSL/TLS library targeted for use by embedded systems developers. It is an open source implementation of TLS (SSL 3.0, TLS 1.0, 1.1, 1.2, 1.3, and DTLS 1.0, 1.2, and 1.3) written in the C programming lan ...

References

External links

The hash function RIPEMD-160

RIPEMD-160 Ecrypt page

RIPEMD-128bit Algorithm
{{Cryptography navbox , hash Cryptographic hash functions

History

RIPEMD-160 hashes

Implementations

See also

References

External links