doc/reference.rst

Reference
=========

This is the class and function reference. For more usage information
see the :ref:`usage` page.

Functions
---------

.. autofunction:: rsa.encrypt

.. autofunction:: rsa.decrypt

.. autofunction:: rsa.sign

.. autofunction:: rsa.verify

.. autofunction:: rsa.newkeys(keysize)


Classes
-------

.. note::

    Storing public and private keys via the `pickle` module is possible.
    However, it is insecure to load a key from an untrusted source.
    The pickle module is not secure against erroneous or maliciously
    constructed data. Never unpickle data received from an untrusted
    or unauthenticated source.

.. autoclass:: rsa.PublicKey
    :members:
    :inherited-members:

.. autoclass:: rsa.PrivateKey
    :members:
    :inherited-members:

Exceptions
----------

.. autoclass:: rsa.pkcs1.CryptoError(Exception)

.. autoclass:: rsa.pkcs1.DecryptionError(CryptoError)

.. autoclass:: rsa.pkcs1.VerificationError(CryptoError)


.. index:: VARBLOCK (file format)

The VARBLOCK file format
++++++++++++++++++++++++

.. warning::

    The VARBLOCK format is NOT recommended for general use, has been deprecated since
    Python-RSA 3.4, and was removed in version 4.0. It's vulnerable to a
    number of attacks. See :ref:`bigfiles` for more information.

The VARBLOCK file format allows us to encrypt files that are larger
than the RSA key. The format is as follows; || denotes byte string
concatenation::

 VARBLOCK := VERSION || BLOCK || BLOCK || ...

 VERSION := 1

 BLOCK := LENGTH || DATA

 LENGTH := varint-encoded length of the following data, in bytes

 DATA := the data to store in the block

The varint-format was taken from Google's Protobuf_, and allows us to
efficiently encode an arbitrarily long integer.

.. _Protobuf:
    https://code.google.com/apis/protocolbuffers/docs/encoding.html#varints


Module: rsa.core
----------------

At the core of the RSA encryption method lie these functions. They
both operate on (arbitrarily long) integers only. They probably aren't
of much use to you, but I wanted to document them anyway as they are
the core of the entire library.

.. autofunction:: rsa.core.encrypt_int

.. autofunction:: rsa.core.decrypt_int