DES-加密解密算法的C++实现--实验报告

1实验一1、实验题目利用C/C++编程实现DES加密算法或MD5加密算法。我选择的是用C++语言实现DES的加密算法。2、实验目的通过编码实现DES算法或MD5算法，深入掌握算法的加密原理，理解其实际应用价值，同时要求用C/C++语言实现该算法，让我们从底层开始熟悉该算法的实现过程3、实验环境操作系统：WIN7旗舰版开发工具：VisualStudio2010旗舰版开发语言：C++4、实验原理DES加密流程2如上图所示为DES的加密流程，其中主要包含初始置换，压缩换位1，压缩换位2，扩展置换，S盒置换，异或运算、终结置换等过程。初始置换是按照初始置换表将64位明文重新排列次序扩展置换是将原32为数据扩展为48位数据，它主要由三个目的：1、产生与子密钥相同的长度2、提供更长的结果，使其在加密过程中可以被压缩3、产生雪崩效应，使得输入的一位将影响两个替换S盒置换是DES算法中最核心的内容，在DES中，只有S盒置换是非线性的，它比DES中其他任何一步都提供更好的安全性终结置换与初始置换相对应，它们都不影响DES的安全性，主要目的是为了更容易将明文与密文数据一字节大小放入DES的f算法中DES解密流程与加密流程基本相同，只不过在进行16轮迭代元算时，将子密钥生成的K的次序倒过来进行迭代运算5、实验过程记录在对DES算法有了清晰的认识后，编码过程中我将其分为几个关键部分分别进行编码，最后将整个过程按顺序执行，即可完成DES的加密，代码的主要几个函数如下：//Byte转为BitByteToBit(ElemTypech,ElemTypebit[8])//Bit转为ByteBitToByte(ElemTypebit[8],ElemType&ch)//初始置换InitialEX(ElemTypeInorder[64],ElemTypeDisorder[64])//终结置换AntiEx(ElemTypeDisorder[64])//扩展置换ExpandEX(ElemTypeRightMsg[32],ElemTypeExpandMsg[48])//16轮迭代加密MoveLeft(ElemTypeC[28],ElemTypeD[28],ElemTypeL0[32],ElemTypeR0[32])3//16轮迭代解密mMoveLeft(ElemTypeC[28],ElemTypeD[28],ElemTypeL0[32],ElemTypeR0[32])//生成48位子密钥GetCD48(ElemTypeC[28],ElemTypeD[28],ElemTypeSecret[48])//48位明文与子密钥进行异或运算XOR(ElemTypeExpandMsg[48],ElemTypeSecret[48],ElemTypeResult[48])//S盒四位输出getSOut(ElemTypeResult[48],ElemTypeSout[32])//直接置换DirExchange(ElemTypeSout[32],ElemTypeDirOut[32])//Li与Ri进行抑或运算XORLR(ElemTypeDirOut[32],ElemTypeLeft[32],ElemTypeResult[32])函数执行次序和调用关系关系如下：6.源代码//DES.cpp:定义控制台应用程序的入口点。//#includestdafx.h#includefunction.h#includeiostream#includebitset#includestringusingnamespacestd;//置换矩阵intIP_EX[64]={58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7};intIP_ANTEX[64]={40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,41,10,50,18,58,26,33,1,41,9,49,17,57,25};//扩展矩阵intEXTEND[48]={32,1,2,3,4,5,4,5,6,7,8,9,8,9,10,11,12,13,12,13,14,15,16,17,16,17,18,19,20,21,20,21,22,23,24,25,24,25,26,27,28,29,28,29,30,31,1,2};//S盒intS[8][4][16]={{{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7},{0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8},{4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0},{15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13}},{{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10},{3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5},{0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15},{13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9}},{{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8},{13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1},{13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7},{1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12}},{{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15},{13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9},{10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4},{3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14}},{{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9},{14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6},{4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14},{11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3}},{{12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11},{10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8},{9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6},{4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13}},{{4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1},{13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6},{1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2},{6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12}},{{13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7},{1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2},{7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8},{2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}}};intDIREX[32]={16,7,20,21,29,12,28,17,1,15,23,26,5,18,31,10,2,8,24,14,32,27,3,9,19,13,30,6,22,11,4,25};//左移移位表intMOVELEFT[16]={1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};//压缩换位表2intCutEX[48]={14,17,11,24,1,5,3,28,15,6,21,10,23,19,12,4,26,8,16,7,27,20,13,2,41,52,31,37,47,55,30,40,51,45,33,48,44,49,39,56,34,53,46,42,50,36,29,32};typedefcharElemType;ElemTypesubsec[16][48];//Byte转bitintByteToBit(ElemTypech,ElemTypebit[8]){for(intindex=7;index=0;index--){bit[index]=(chindex)&1;//cout(int)bit[index];}return0;}//bit转ByteintBitToByte(ElemTypebit[8],ElemType&ch){ElemTypetempch=0;ElemTypetempbit[8];for(inti=0;i8;i++){tempbit[i]=bit[i];}tempbit[7]=0;for(intindex=7;index=0;index--){tempch=tempch|(tempbit[index](index));}ch=tempch;//cout(char)tempchendl;return0;}//按64位分一组voidGet64Bit(ElemTypech[8],ElemTypebit[64]){ElemTypetemp[8];intcount=0;for(inti=0;i8;i++){ByteToBit(ch[i],temp);for(intj=0;j8;j++){bit[count*8+j]=temp[7-j];}count++;}}//初始置换voidInitialEX(ElemTypeInorder[64],ElemTypeDisorder[64]){for(inti=0;i64;i++){Disorder[i]=Inorder[IP_EX[i]-1];}}//逆置换voidAntiEx(ElemTypeDisorder[64]){ElemTypetemp[64];for(inti=0;i64;i++){temp[i]=Disorder[i];}for(inti=0;i64;i++){Disorder[i]=temp[IP_ANTEX[i]-1];}}//扩展置换voidExpandEX(ElemTypeRightMsg[32],ElemTypeExpandMsg[48]){for(inti=0;i48;i++){ExpandMsg[i]=RightMsg[EXTEND[i]-1];}}//16轮加密迭代voidMoveLeft(ElemTypeC[28],ElemTypeD[28],ElemTypeL0[32],ElemTypeR0[32]){ElemTypeSecret[48];//子密钥ElemTypeResult[48];//每轮异或结果ElemTypeSout[32];//每轮S盒输出ElemTypeDirOut[32];//直接置换输出ElemTypeRResult[32];ElemTypeLResult[32];ElemTypeExpandMsg[48];ElemTypetemp[32];for(inti=0;i32;i++){LResult[i