Module: Digest (Ruby 2.2.2)
Description: Module : Digest - Ruby 2.2.2

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Support for the Ruby 2.2 series has ended. See here for reference.

### Home Classes Methods

### In Files

- digest/bubblebabble/bubblebabble.c
- digest/digest.c
- digest/lib/digest.rb
- digest/md5/md5init.c
- digest/rmd160/rmd160init.c
- digest/sha1/sha1init.c
- digest/sha2/lib/sha2.rb

### Namespace

- MODULE Digest::Instance
- CLASS Digest::Base
- CLASS Digest::Class
- CLASS Digest::MD5
- CLASS Digest::RMD160
- CLASS Digest::SHA1
- CLASS Digest::SHA2

### Methods

- ::bubblebabble
- ::hexencode

### Class/Module Index

Quicksearch

- Digest
- Digest::Base
- Digest::Class
- Digest::Instance
- Digest::MD5
- Digest::RMD160
- Digest::SHA1
- Digest::SHA2
- Object

No matching classes.

# Digest

This module provides a framework for message digest libraries.

You may want to look at OpenSSL::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 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.

## Examples¶ ↑

    require 'digest'

    # Compute a complete digest
    Digest::SHA256.digest 'message'       #=> "\xABS\n\x13\xE4Y..."

    sha256 = Digest::SHA256.new
    sha256.digest 'message'               #=> "\xABS\n\x13\xE4Y..."

    # Other encoding formats
    Digest::SHA256.hexdigest 'message'    #=> "ab530a13e459..."
    Digest::SHA256.base64digest 'message' #=> "q1MKE+RZFJgr..."

    # Compute digest by chunks
    md5 = Digest::MD5.new
    md5.update 'message1'
    md5 << 'message2'                     # << is an alias for update

    md5.hexdigest                         #=> "94af09c09bb9..."

    # Compute digest for a file
    sha256 = 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 at web.mit.edu/kenta/www/one/bubblebabble/spec/jrtrjwzi/draft-huima-01.txt.

## 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.

### Constants

REQUIRE_MUTEX

  A mutex for Digest().

### Public Class Methods

bubblebabble(string) → bubblebabble_string click to toggle source

Returns a BubbleBabble encoded version of a given string.

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

hexencode(string) → hexencoded_string click to toggle source

Generates a hex-encoded version of a given string.

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