Linux環(huán)境下的密文聊天系統(tǒng)的設(shè)計(jì)與實(shí)現(xiàn)設(shè)計(jì)與實(shí)現(xiàn)


LINUX環(huán)境下的密文聊天系統(tǒng)的設(shè)計(jì)與實(shí)現(xiàn)

摘  要
隨著計(jì)算機(jī)的不斷普及和互聯(lián)網(wǎng)技術(shù)在全球領(lǐng)域的高速發(fā)展。越來(lái)越多的人使用到了聊天程序。聊天程序給人們帶來(lái)通信便利的同時(shí)也存在著一些安全隱患，傳統(tǒng)的聊天程序以明文方式傳送聊天內(nèi)容，這樣就給一些用心不良的人大開(kāi)方便之門(mén)。本系統(tǒng)正是基于以上原因而設(shè)計(jì)的加密聊天程序。聊天程序采用服務(wù)器/客戶端模式。在Linux環(huán)境下采用socket套接口編程，服務(wù)器程序以創(chuàng)建線程池的方式為每一個(gè)客戶服務(wù)。聊天內(nèi)容由服務(wù)器轉(zhuǎn)發(fā)。在聊天程序中加入了對(duì)稱加密算法DES和非對(duì)稱加密算法RSA。其基本實(shí)現(xiàn)是由服務(wù)器端生成RSA的公鑰和私鑰，由客戶端生成DES對(duì)稱密鑰，服務(wù)器端傳送公鑰至客戶端加密DES密鑰之后回傳服務(wù)器，服務(wù)器再用本地的私鑰解密獲得DES密鑰。此后雙方的通信由DES密鑰加密后傳送，這樣既能高效的加密明文又能在信道上安全的傳送密鑰使得密鑰間的共享成為現(xiàn)實(shí)。

關(guān)鍵詞：對(duì)稱加密算法；非對(duì)稱加密算法；會(huì)話密鑰；聊天系統(tǒng)

 
The Design and implementation of encrypted chat system based on Linux

Abstract
Along with Computer becoming more and more popular and Internet technology developing rapidly, a lot of People began to use the IM(chat program). Chat program brings people more convenience, but at the same time, security problem existed. The traditional chat program sends the message by plain text, which open the door for the bad man. This encrypted chat system is right based on the point. The system is in C/S architecture using socket based on Linux. The server program serves each client in the way of establishing thread and is responsible to transfer message. The DES algorithm and RSA algorithm are used to encrypt in this program. The basic principle is that the server generates RSA public key and private key and client generates DES symmetrical secret key. Firstly, the server sends the public key to client, and then client sends it back after encrypting DES secret key. Secondly, the Server uses local private key to decode to obtain the DES private key. After then, the message is sent after encrypted by DES secret key. So the plain text can be encrypted effectively and sent in channel in security.

Key words: symmetry encrypting program; unsymmetrical encrypting program; conversation key; chat system
 
目  錄
論文總頁(yè)數(shù)：30頁(yè)
1 引言 1
1.1 課題背景 1
1.2 國(guó)內(nèi)外研究現(xiàn)狀 1
1.3 本課題研究的意義 1
2 所采用技術(shù)的先進(jìn)性分析 1
2.1 DES算法 1
2.2 RSA算法 2
2.3 線程池 2
3 系統(tǒng)需求分析 3
3.1 聊天程序功能分析 3
3.2 加密算法 3
4 系統(tǒng)總體設(shè)計(jì)和模塊劃分 3
4.1 系統(tǒng)總體設(shè)計(jì) 3
4.2 模塊劃分 4
4.2.1 DES算法模塊 4
4.2.2 RSA算法模塊 6
4.2.3 聊天程序模塊 7
5 系統(tǒng)實(shí)現(xiàn) 9
5.1 DES核心代碼 9
5.2 RSA核心代碼 12
5.3 WEB注冊(cè)頁(yè)面核心代碼 15
5.4 服務(wù)器端核心代碼 18
5.5 客戶端核心代碼 21
結(jié)    論 25
參考文獻(xiàn) 25
致    謝 26
聲    明 27
附    錄 28