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.

Add this line to your application's Gemfile:

gem'digest'

And then execute:

$ bundle 

Or install it yourself as:

$ gem install digest 

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 at http://web.mit.edu/kenta/www/one/bubblebabble/spec/jrtrjwzi/draft-huima-01.txt.

Different digest algorithms (or hash functions) are available:

MD5:: See RFC 1321 The MD5 Message-Digest Algorithm RIPEMD-160:: As Digest::RMD160. See http://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: http://csrc.nist.gov/publications/PubsFIPS.html.

If you want to use digest algorithms in your C extension, you can use the digest.h header file provided by digest gem. You should add the following code to your extconf.rb:

spec=Gem::Specification.find_by_name("digest")source_dir=File.join(spec.full_gem_path,"ext","digest") $INCFLAGS += " -I#{source_dir}"

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/ruby/digest.

The gem is available as open source under the terms of the 2-Clause BSD License.