crystal-argon2
crystal-argon2
This Crystal shard provides C bindings, and a simplified interface, to the Argon2 algorithm. Argon2 is the official winner of the Password Hashing Competition, a several year project to identify a successor to bcrypt/PBKDF/scrypt methods of securely storing passwords. This is an independent project and not official from the PHC team.
This project is mostly a clone of this awesome ruby project technion/ruby-argon2
Installation
- Add the dependency to your
shard.yml
:
dependencies:
crystal-argon2:
github: sushichain/crystal-argon2
- Run
shards install
Design
This project has several key tenants to its design:
- The reference Argon2 implementation is to be used "unaltered". To ensure compliance with this goal, and encourage regular updates from upstream, the upstream library is implemented as a git submodule, and is intended to stay that way.
- Security and maintainability take top priority. This can have an impact on platform support. A PR that contains platform specific code paths is unlikely to be accepted.
- Tested versions are Crystal 0.27.0 on MacOS and Linux. No assertions are made on other platforms.
- Errors from the C interface are raised as Exceptions. There are a lot of exception classes, but they tend to relate to things like very broken input, and code bugs. Calls to this library should generally not require a rescue.
- Test suite should aim for 100% code coverage.
- Default work values should not be considered constants. They may change.
- Not exposing the threads parameter is a design choice. I believe there is significant risk, and minimal gain in using a value other than '1'. Four threads on a four core box completely ties up the entire server to process one user logon. If you want more security, increase m_cost.
Usage
require "crystal-argon2"
To generate a hash using specific time and memory cost:
hasher = Argon2::Password.new(t_cost: 2, m_cost: 16)
hasher.create("password")
=> "$argon2i$v=19$m=65536,t=2,p=1$jL7lLEAjDN+pY2cG1N8D2g$iwj1ueduCvm6B9YVjBSnAHu+6mKzqGmDW745ALR38Uo"
To utilise default costs:
hasher = Argon2::Password.new
hasher.create("password")
If you follow this pattern, it is important to create a new Argon2::Password
every time you generate a hash, in order to ensure a unique salt. See issue 23 for more information.
Alternatively, use this shotcut:
Argon2::Password.create("password")
=> "$argon2i$v=19$m=65536,t=2,p=1$61qkSyYNbUgf3kZH3GtHRw$4CQff9AZ0lWd7uF24RKMzqEiGpzhte1Hp8SO7X8bAew"
You can then use this function to verify a password against a given hash. Will return either true or false.
Argon2::Password.verify_password("password", secure_password)
Development
- build the C library
cd ext && make
- run specs:
crystal spec
Using crystal_lib
To generate the initial crystal bindings using this library:
- git clone https://github.com/crystal-lang/crystal_lib.git
- download the argon2 code from here https://github.com/P-H-C/phc-winner-argon2/releases
- use
make
to build the argon2 code - create a crystal bindings file for argon2 that will be run from crystal_lib (see below)
- export LLVM_CONFIG=/usr/local/opt/llvm/bin/llvm-config (use the correct path for your LLVM install)
- crystal run src/main.cr -- path/to/argon2_bindings.cr
argon2_bindings.cr example
# export LLVM_CONFIG=/usr/local/opt/llvm/bin/llvm-config
@[Include("../phc-winner-argon2/include/argon2.h")]
@[Link("argon2")]
lib LibArgon2
fun argon2i_hash_raw
fun argon2i_hash_encoded
fun argon2d_hash_raw
fun argon2d_hash_encoded
fun argon2id_hash_raw
fun argon2id_hash_encoded
fun argon2i_verify
fun argon2d_verify
fun argon2id_verify
end
Contributing
- Fork it (https://github.com/sushichain/crystal-argon2/fork)
- Create your feature branch (
git checkout -b my-new-feature
) - Commit your changes (
git commit -am 'Add some feature'
) - Push to the branch (
git push origin my-new-feature
) - Create a new Pull Request
Contributors
- Kingsley Hendrickse - creator and maintainer