This module provides a framework for message digest libraries.
You may want to look at OpenSSL::Digest as it supports support more algorithms.
A cryptographic hash function is a procedure that takes data and return a fixed bit string : the hash value, also known as digest. Hash functions are also called one-way functions, it is easy to compute a digest from a message, but it is infeasible to generate a message from a digest.
Example
require 'digest'
# Compute a complete digest
sha256 = Digest::SHA256.new
digest = sha256.digest message
# Compute digest by chunks
sha256 = Digest::SHA256.new
sha256.update message1
sha256 << message2 # << is an alias for update
digest = sha256.digest
Digest algorithms
Different digest algorithms (or hash functions) are available :
- HMAC
-
See FIPS PUB 198 The Keyed-Hash Message Authentication Code (HMAC)
- RIPEMD-160
-
(as Digest::RMD160) see homes.esat.kuleuven.be/~bosselae/ripemd160.html
- SHA1
-
See FIPS 180 Secure Hash Standard
- SHA2 family
-
See FIPS 180 Secure Hash Standard which defines the following algorithms:
-
SHA512
-
SHA384
-
SHA256
-
The latest versions of the FIPS publications can be found here: csrc.nist.gov/publications/PubsFIPS.html
Additionally Digest::BubbleBabble encodes a digest as a sequence of consonants and vowels which is more recognizable and comparable than a hexadecimal digest. See en.wikipedia.org/wiki/Bubblebabble
- MODULE Digest::Instance
- CLASS Digest::Base
- CLASS Digest::Class
- CLASS Digest::HMAC
- CLASS Digest::MD5
- CLASS Digest::RMD160
- CLASS Digest::SHA1
- CLASS Digest::SHA2