This gem is a C-extension for using BLAKE2s in Ruby.

BLAKE2 comes in two basic flavors:

BLAKE2b (or just BLAKE2) is optimized for 64-bit platforms and produces digests of any size between 1 and 64 bytes.

BLAKE2s is optimized for 8- to 32-bit platforms and produces digests of any size between 1 and 32 bytes.

Both BLAKE2b and BLAKE2s are believed to be highly secure and perform well on any platform, software, or hardware. BLAKE2 does not require a special "HMAC" (Hashed Message Authentication Code) construction for keyed message authentication as it has a built-in keying mechanism.

https://tools.ietf.org/html/rfc7693#page-3

This implementation supports the BLAKE2s variant with 32 Bytes of output.

The C code for this gem is taken from the official reference C implementation as of commit 02bf34f3d49c205812c34dfce9123a7c74509605.

For a detailed explanation about BLAKE2s, here's the offical website.

gem install blake2

require 'blake2'

# The UTF-8 String (Required) that you want to digest.
input   = 'abc'

# The main application of keyed BLAKE2 is as a message authentication code (MAC)
# By default `Blake2::Key.none` is used.
key = Blake2::Key.none
# key = Blake2::Key.from_string("foo bar baz")
# key = Blake2::Key.from_hex('DEADBEAF')
# key = Blake2::Key.from_bytes([222, 173, 190, 175])

# The output length in Bytes of the Hash, Max and Default is 32.
out_len = 32

# HEX OUTPUT
############

Blake2.hex(input)
=> "508c5e8c327c14e2e1a72ba34eeb452f37458b209ed63a294d999b4c86675982"

Blake2.hex(input, key)
=> "508c5e8c327c14e2e1a72ba34eeb452f37458b209ed63a294d999b4c86675982"

Blake2.hex(input, key, out_len)
=> "508c5e8c327c14e2e1a72ba34eeb452f37458b209ed63a294d999b4c86675982"

# BYTES OUTPUT
##############

Blake2.bytes(input)
=> [80, 140, 94, ...]

Blake2.bytes(input, key)
=> [80, 140, 94, ...]

Blake2.bytes(input, key, out_len)
=> [80, 140, 94, ...]

After checking out the repo, run bin/setup to install dependencies. Then, run rake full to build and test, or rake test to only 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.

1. Fork it ( https://github.com/franckverrot/blake2/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request

Franck Verrot, Copyright 2014. See LICENSE.txt.