用C++实现DES对数据加密和解密

摘要

随着计算机和通信技术的飞速发展，密码学已经渗透到了政治、经济、文化乃至个人隐私等领域，使用加密技术来保护信息的安全变得越来越重要。这篇的重点在于通过对加密算法的学习来对它们进行比较，并将它们运用到实践中。
分为9章，主要有开发工具的介绍、DES的流程和加密方法原理，最后是MFC的界面。第1章简单介绍了MFC的功能和作用；第2章较为详细地介绍了DES加密和解密算法。第3章介绍DES的缺陷和不足。第4章介绍DES的工作模式包括DES的变形。第5章是DES的主要函数。第6章就是DES的代码。第7章就是对DES的代码正式测试，包括密码的C实现及加密解密器界面的C++实现和几种功能的执行、测试和使用。最后列出了1些参考的文献。
这篇主要是体现加密的原理和方法，对于现在计算机硬件高速发展的现在，DES的64位密钥（实际只有56位）实在太少很容易被破解，不适于现在的社会，作为典型的加密方法DES还是值得我们去学习的，这就是我写这篇的主要目的。

关键词:数据加密标准；DES；密钥；数据加密；数据解密；S盒

Abstract

Fly technically along with the calculator and correspondences to develop soon, the password learn to have already seeped through politics, economy, culture is go to personal privacy etc. realm, the usage encrypt the technique to protect the safety of information to become more and more important. The point of this sis lie in pass to come to carry on the comparison to them towards encrypting the calculate way of study, and make use of them to fulfillment. （科教论文网 Lw.nsEAc.com编辑整理）
    The thesis is divided into nine, mainly having the process of introduction, DES of develop the tool and encrypting the method principle, the end is a MFC interface. Chapter 1 introduced the MFC the function and the function in brief; A process that compares to introduced the DES to encrypt the calculate way in detail and decrypt. A the blemish and the shortage that introduces the DES.A work mode that introduces the DES includes the DES to transform. Chapter 5 is DES main function. Chapter 6 is DES codes. Chapter 7 is the code formality test to the DES, including the C of the password realization and encrypting the C of decrypt the machine interface++ realization and a few performances of password function, test and usages. Listed some cultural heritages of reference finally.
This sis is mainly the principle and methods that the body encrypts now, now of high-speed development for the calculator hardware of now, DES 64 bit keys (actual only 56) are really too little very easily was break solution, unwell in now of society, the conduct and actions typical model still encrypt the method DES worthy of we study of, this be I write this sis of main purpose

Keyword:the standard of the data encrypts;DES;key; the data encrypt;the data decrypt;s box