Pure Python RSA implementation

Python-RSA is a pure-Python RSA implementation. It supports encryption and decryption, signing and verifying signatures, and key generation according to PKCS#1 version 1.5. It can be used as a Python library as well as on the commandline. The code was mostly written by Sybren A. Stüvel.

Documentation can be found at the Python-RSA homepage. For all changes, check the changelog.

Download and install using:

pip install rsa

or download it from the Python Package Index.

The source code is maintained at GitHub and is licensed under the Apache License, version 2.0

Security

Because of how Python internally stores numbers, it is very hard (if not impossible) to make a pure-Python program secure against timing attacks. This library is no exception, so use it with care. See https://securitypitfalls.wordpress.com/2018/08/03/constant-time-compare-in-python/ for more info.

Major changes in 4.1

Version 4.0 was the last version to support Python 2 and 3.4. Version 4.1 is compatible with Python 3.5+ only.

Major changes in 4.0

Version 3.4 was the last version in the 3.x range. Version 4.0 drops the following modules, as they are insecure:

• rsa._version133
• rsa._version200
• rsa.bigfile
• rsa.varblock

Those modules were marked as deprecated in version 3.4.

Furthermore, in 4.0 the I/O functions is streamlined to always work with bytes on all supported versions of Python.

Version 4.0 drops support for Python 2.6 and 3.3.