Metadata-Version: 1.1
Name: xxtea
Version: 1.0.2
Summary: xxtea
Home-page: https://github.com/ifduyue/xxtea
Author: Yue Du
Author-email: ifduyue@gmail.com
License: BSD
Description: xxtea |travis-badge| |pypi-badge|
        ==================================
        
        .. |travis-badge| image:: https://travis-ci.org/ifduyue/xxtea.png
            :target: https://travis-ci.org/ifduyue/xxtea
        
        .. |pypi-badge| image:: https://badge.fury.io/py/xxtea.svg
            :target: http://badge.fury.io/py/xxtea
        
        .. _XXTEA: http://en.wikipedia.org/wiki/XXTEA
        .. _longs2bytes: https://github.com/ifduyue/xxtea/blob/master/xxtea.c#L130
        .. _bytes2longs: https://github.com/ifduyue/xxtea/blob/master/xxtea.c#L102
        .. _PKCS#7: http://en.wikipedia.org/wiki/Padding_%28cryptography%29#PKCS7
        
        XXTEA_ implemented as a Python extension module, licensed under 2-clause BSD.
        
        The XXTEA_ algorithm takes a 128-bit key and operates on an array of 32-bit
        integers (at least 2 integers), but it doesn't define the conversions between
        bytes and array. Due to this reason, many XXTEA implementations out there are
        not compatible with each other.
        
        In this implementation,  the conversions between bytes and array are
        taken care of by longs2bytes_ and bytes2longs_. `PKCS#7`_ padding is also used
        to make sure that the input bytes are padded to multiple of 4-byte (the size
        of a 32-bit integer) and at least 8-byte long (the size of two 32-bit integer,
        which is required by the XXTEA_ algorithm). As a result of these measures,
        you can encrypt not only texts, but also any binary bytes of any length.
        
        
        Installation
        -------------
        
        ::
        
            $ pip install xxtea -U
        
        
        Usage
        -----------
        
        This module provides four functions: ``encrypt()``, ``decrypt()``,
        ``encrypt_hex()``, and ``decrypt_hex()``.
        
        Python 2:
        
        .. code-block:: python
        
            >>> import os
            >>> import xxtea
            >>> 
            >>> key = os.urandom(16)  # Key must be a 16-byte string.
            >>> s = "xxtea is good"
            >>> 
            >>> enc = xxtea.encrypt(s, key)
            >>> dec = xxtea.decrypt(enc, key)
            >>> s == dec
            True
            >>> 
            >>> hexenc = xxtea.encrypt_hex(s, key)
            >>> hexenc
            'd1d8e82461dd5828397c32ad265ee225'
            >>> s == xxtea.decrypt_hex(hexenc, key)
            True
            >>> 
            >>> enc.encode('hex') == hexenc
            True
        
        Python 3:
        
        .. code-block:: Python
        
            >>> import os
            >>> import xxtea
            >>> import binascii
            >>> 
            >>> key = os.urandom(16)  # Key must be a 16-byte string.
            >>> s = b"xxtea is good"
            >>> 
            >>> enc = xxtea.encrypt(s, key)
            >>> dec = xxtea.decrypt(enc, key)
            >>> s == dec
            True
            >>> 
            >>> hexenc = xxtea.encrypt_hex(s, key)
            >>> hexenc
            b'7ad85672d770fb5cf636c49d57e732ae'
            >>> s == xxtea.decrypt_hex(hexenc, key)
            True
            >>> 
            >>> binascii.hexlify(enc) == hexenc
        
        ``encrypt_hex()`` and ``decrypt_hex()`` operate on ciphertext in a hexadecimal
        representation. They are exactly equivalent to:
        
        Python 2:
        
        .. code-block:: python
        
            >>> hexenc = xxtea.encrypt(s, key).encode('hex')
            >>> s == xxtea.decrypt(hexenc.decode('hex'), key)
            True
        
        Python 3:
        
        .. code-block:: python
        
            >>> hexenc = binascii.hexlify(xxtea.encrypt(s, key))
            >>> s == xxtea.decrypt(binascii.unhexlify(hexenc), key)
            True
        
        Catching Exceptions
        ---------------------
        
        It is possible to throw a ``ValueError`` or a ``TypeError`` during calling
        ``decrypt()`` and ``decrypt_hex()``. Better to catch them, or your program
        would exit.
        
        .. code-block:: python
        
            >>> from __future__ import print_function
            >>> import xxtea
            >>> 
            >>> def try_catch(func, *args, **kwargs):
            ...     try:
            ...         func(*args, **kwargs)
            ...     except Exception as e:
            ...         print(e.__class__.__name__, ':', e)
            ...         
            ...     
            ... 
            >>> try_catch(xxtea.decrypt, '', key='')
            ValueError : Need a 16-byte key.
            >>> try_catch(xxtea.decrypt, '', key=' '*16)
            ValueError : Invalid data, data length is not a multiple of 4, or less than 8.
            >>> try_catch(xxtea.decrypt, ' '*8, key=' '*16)
            ValueError : Invalid data, illegal PKCS#7 padding. Could be using a wrong key.
            >>> try_catch(xxtea.decrypt_hex, ' '*8, key=' '*16)
            TypeError : Non-hexadecimal digit found
            >>> try_catch(xxtea.decrypt_hex, 'abc', key=' '*16)
            TypeError : Odd-length string
            >>> try_catch(xxtea.decrypt_hex, 'abcd', key=' '*16)
            ValueError : Invalid data, data length is not a multiple of 4, or less than 8.
        
Keywords: xxtea
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: BSD License
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.6
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.2
Classifier: Programming Language :: Python :: 3.3
Classifier: Programming Language :: Python :: 3.4
Classifier: Programming Language :: Python :: 3.5
