Low-level Python CFFI Bindings for Argon2

argon2-cffi-bindings provides low-level CFFI bindings to the Argon2 password hashing algorithm including a vendored version of them.

The currently vendored Argon2 commit ID is f57e61e.

If you want to hash passwords in an application, this package is not for you. Have a look at argon2-cffi with its high-level abstractions!

These bindings have been extracted from argon2-cffi and it remains its main consumer. However, they may be used by other packages that want to use the Argon2 library without dealing with C-related complexities.

Usage

argon2-cffi-bindings is available from PyPI. The provided CFFI bindings are compiled in API mode.

Best effort is given to provide binary wheels for as many platforms as possible.

Disabling Vendored Code

A copy of Argon2 is vendored and used by default, but can be disabled if argon2-cffi-bindings is installed using:

$ env ARGON2_CFFI_USE_SYSTEM=1 \
  python -m pip install --no-binary=argon2-cffi-bindings argon2-cffi-bindings

Overriding Automatic SSE2 Detection

Usually the build process tries to guess whether or not it should use SSE2-optimized code (see _ffi_build.py for details). This can go wrong and is problematic for cross-compiling.

Therefore you can use the ARGON2_CFFI_USE_SSE2 environment variable to control the process:

• If you set it to 1, argon2-cffi-bindings will build with SSE2 support.
• If you set it to 0, argon2-cffi-bindings will build without SSE2 support.
• If you set it to anything else, it will be ignored and argon2-cffi-bindings will try to guess.

However, if our heuristics fail you, we would welcome a bug report.

Python API

Since this package is intended to be an implementation detail, it uses a private module name to prevent your users from using it by accident.

Therefore you have to import the symbols from _argon2_cffi_bindings:

from _argon2_cffi_bindings import ffi, lib

Please refer to cffi documentation on how to use the ffi and lib objects.

The list of symbols that are provided can be found in the _ffi_build.py file.

Project Information

argon2-cffi-bindings is available under the MIT license, available from PyPI, the source code and documentation can be found on GitHub.

argon2-cffi-bindings targets Python 3.6 and later, including PyPy3.

Credits & License

argon2-cffi-bindings is written and maintained by Hynek Schlawack. It is released under the MIT license.

The development is kindly supported by Variomedia AG.

The authors of Argon2 were very helpful to get the library to compile on ancient versions of Visual Studio for ancient versions of Python.

The documentation quotes frequently in verbatim from the Argon2 paper to avoid mistakes by rephrasing.

Vendored Code

The original Argon2 repo can be found at https://github.com/P-H-C/phc-winner-argon2/.

Except for the components listed below, the Argon2 code in this repository is copyright (c) 2015 Daniel Dinu, Dmitry Khovratovich (main authors), Jean-Philippe Aumasson and Samuel Neves, and under CC0 license.

The string encoding routines in src/encoding.c are copyright (c) 2015 Thomas Pornin, and under CC0 license.

The BLAKE2 code in src/blake2/ is copyright (c) Samuel Neves, 2013-2015, and under CC0 license.