The Keccak (SHA3) digest for Ruby
This Ruby extension exposes the Keccak (SHA3) digest
C bindings in the non-final version used by Ethereum. It is based on the reference
C implementation, version 3.2. The exposed interface is almost identical to that of the
digest standard library. See #16.
⚠️ Note: version
~> 1.3 exposes
Digest::Keccak) whereas version
~> 1.2 maintains the old
Digest::SHA3) for backward compatibility. Only use
~> 1.2 if you want to lazy-patch your library. It works, but it's not recommended. Use
~> 1.3 and simply rename SHA3 to Keccak.
The gem is called
bundle add keccak gem install keccak
gem 'keccak', '~> 1.3'
Note: as of version
digest-sha3 (historic name, see below) requires Ruby 2.2. The new
~> v1.2 now also supports Ruby 3.0. The last version that worked on older Ruby (1.x) versions was
~> v1.0. It can be found at the no longer maintained
digest-sha3 repository from 2015.
This gem extends the
digest/* module by a
require 'digest/keccak' # Generate 512-bit digest. Digest::Keccak.digest("foo") # => "\025\227\204*..." Digest::Keccak.hexdigest("foo") # => "1597842a..." # Generate 224-bit digest. Digest::Keccak.digest("foo", 224) # => "\332\251M\247..." Digest::Keccak.hexdigest("foo", 224) # => "daa94da7..." # Use this interface to feed data in chunks. 512-bit by default. digest = Digest::Keccak.new digest.update("f") digest.update("o") digest.update("o") digest.digest # => "\025\227\204*..." digest.hexdigest # => "1597842a..." # You can pass a hash length to the constructor. digest = Digest::Keccak.new(224)
Keccak supports five hash lengths: 224-bit, 256-bit, 384-bit, 512-bit and variable length. Variable length is not supported by this Ruby extension. Unless the user specifies otherwise, this Ruby extension assumes 512-bit.
Running the test suite
Run the test suite as follows:
bundle install make test
A part of the test suite is automatically generated from Keccak's reference test suite.
Warning: Keccak vs. SHA3
Note: This gem still uses the
Digest::SHA3 namespace in version
~> 1.2 for reasons of backward compatibility and long-term maintainability. See history section below.
⚠️ This gem does not implement the final FIPS202 standard, today known as SHA3 but rather an early version, commonly referred to as Keccak. The reason why this is kept around, is that Ethereum uses this earler version of Keccak. See also: Ethereum: Difference between keccak256 and sha3.
If you are looking for the final SHA3 gem, please use the following: https://rubygems.org/gems/sha3
This gem was initially developed and published as
This gem was later patched multiple times:
https://github.com/teamhedge/digest-sha3-ruby (KECCAK, as
https://github.com/sydneyitguy/digest-sha3-ruby (KECCAK, as
- https://github.com/steakknife/digest-sha3-ruby (actual SHA3, do not use for Ethereum)
https://github.com/kotovalexarian/digest-keccak/ (KECCAK, as