module Digest

This module provides a framework for message digest libraries.

You may want to look atOpenSSL::Digest as it supports more algorithms.

A cryptographic hash function is a procedure that takes data and returns a fixed bit string: the hash value, also known asdigest.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.

Examples

require'digest'# Compute a complete digestDigest::SHA256.digest'message'#=> "\xABS\n\x13\xE4Y..."sha256 =Digest::SHA256.newsha256.digest'message'#=> "\xABS\n\x13\xE4Y..."# Other encoding formatsDigest::SHA256.hexdigest'message'#=> "ab530a13e459..."Digest::SHA256.base64digest'message'#=> "q1MKE+RZFJgr..."# Compute digest by chunksmd5 =Digest::MD5.newmd5.update'message1'md5<<'message2'# << is an alias for updatemd5.hexdigest#=> "94af09c09bb9..."# Compute digest for a filesha256 =Digest::SHA256.file'testfile'sha256.hexdigest

Additionally digests can be encoded in “bubble babble” format as a sequence of consonants and vowels which is more recognizable and comparable than a hexadecimal digest.

require'digest/bubblebabble'Digest::SHA256.bubblebabble'message'#=> "xopoh-fedac-fenyh-..."

See the bubble babble specification atweb.mit.edu/kenta/www/one/bubblebabble/spec/jrtrjwzi/draft-huima-01.txt.

Digest algorithms

Different digest algorithms (or hash functions) are available:

MD5

See RFC 1321 TheMD5 Message-Digest Algorithm

RIPEMD-160

AsDigest::RMD160. Seehomes.esat.kuleuven.be/~bosselae/ripemd160.html.

SHA1

See FIPS 180 SecureHash Standard.

SHA2 family

See FIPS 180 SecureHash Standard which defines the following algorithms:

The latest versions of the FIPS publications can be found here:csrc.nist.gov/publications/PubsFIPS.html.

Constants

REQUIRE_MUTEX

A mutex for Digest().

VERSION

Public Class Methods

Source
static VALUErb_digest_s_bubblebabble(VALUE klass, VALUE str){    return bubblebabble_str_new(str);}

Returns a BubbleBabble encoded version of a givenstring.

Source
static VALUErb_digest_s_hexencode(VALUE klass, VALUE str){    return hexencode_str_new(str);}

Generates a hex-encoded version of a givenstring.