1、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
2、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
3、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,ElemTypebit8)/Bit转为ByteBitToByte(ElemTypebit8,ElemType&ch)/初始置换InitialEX(ElemTypeInorder64,ElemTypeDisorder64)/终结置换AntiEx(ElemTypeDisorder64)/扩展置换ExpandEX(ElemTypeRightMsg32,ElemTypeExpandMsg48)/16轮迭代加密MoveLeft(ElemTypeC2
4、8,ElemTypeD28,ElemTypeL032,ElemTypeR032)3/16轮迭代解密mMoveLeft(ElemTypeC28,ElemTypeD28,ElemTypeL032,ElemTypeR032)/生成48位子密钥GetCD48(ElemTypeC28,ElemTypeD28,ElemTypeSecret48)/48位明文与子密钥进行异或运算XOR(ElemTypeExpandMsg48,ElemTypeSecret48,ElemTypeResult48)/S盒四位输出getSOut(ElemTypeResult48,ElemTypeSout32)/直接置换DirExch
5、ange(ElemTypeSout32,ElemTypeDirOut32)/Li与Ri进行抑或运算XORLR(ElemTypeDirOut32,ElemTypeLeft32,ElemTypeResult32)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#include#include#includeusingnamespacestd;/置换矩阵intIP_EX64=58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,3
6、0,22,14,6,64,56,48,40,32,24,16,8,57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7;intIP_ANTEX64=40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,41,10,50,18,58,26,3
7、3,1,41,9,49,17,57,25;/扩展矩阵intEXTEND48=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intS8416=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
8、,2,4,9,1,7,5,11,3,14,10,0,6,13,15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10,3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5,0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15,13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9,10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,1,1
9、0,13,0,6,9,8,7,4,15,14,3,11,5,2,12,7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15,13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9,10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4,3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14,2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9,14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6,4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14
10、,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
11、,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;intDIREX32=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i
12、ntMOVELEFT16=1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1;/压缩换位表2intCutEX48=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;ElemTypesubsec1648;/Byte转bitintByteToBit(ElemTypech,ElemTypebit8)for(intindex=7;i
13、ndex=0;index-)bitindex=(chindex)&1;/cout(int)bitindex;return0;/bit转ByteintBitToByte(ElemTypebit8,ElemType&ch)ElemTypetempch=0;ElemTypetempbit8;for(inti=0;i=0;index-)tempch=tempch|(tempbitindex(index);ch=tempch;/cout(char)tempchendl;return0;/按64位分一组voidGet64Bit(ElemTypech8,ElemTypebit64)ElemTypetemp8
14、;intcount=0;for(inti=0;i8;i+)ByteToBit(chi,temp);for(intj=0;j8;j+)bitcount*8+j=temp7-j;count+;/初始置换voidInitialEX(ElemTypeInorder64,ElemTypeDisorder64)for(inti=0;i64;i+)Disorderi=InorderIP_EXi-1;/逆置换voidAntiEx(ElemTypeDisorder64)ElemTypetemp64;for(inti=0;i64;i+)tempi=Disorderi;for(inti=0;i64;i+)Disor
15、deri=tempIP_ANTEXi-1;/扩展置换voidExpandEX(ElemTypeRightMsg32,ElemTypeExpandMsg48)for(inti=0;i48;i+)ExpandMsgi=RightMsgEXTENDi-1;/16轮加密迭代voidMoveLeft(ElemTypeC28,ElemTypeD28,ElemTypeL032,ElemTypeR032)ElemTypeSecret48;/子密钥ElemTypeResult48;/每轮异或结果ElemTypeSout32;/每轮S盒输出ElemTypeDirOut32;/直接置换输出ElemTypeRResu
16、lt32;ElemTypeLResult32;ElemTypeExpandMsg48;ElemTypetemp32;for(inti=0;i32;i+)LResulti=L0i;RResulti=R0i;for(inti=0;i16;i+)if(MOVELEFTi=1)for(intj=0;j27;j+)Ci=Ci+1;C27=0;elsefor(intj=0;j26;j+)Ci=Ci+2;C26=0;C27=0;ExpandEX(RResult,ExpandMsg);GetCD48(C,D,Secret);for(intj=0;j48;j+)subsec15-ij=Secretj;/获取界面
17、的子密钥XOR(ExpandMsg,Secret,Result);/S盒置换getSOut(Result,Sout);/直接置换DirExchange(Sout,DirOut);/与L进行异或XORLR(DirOut,LResult,temp);for(inti=0;i32;i+)LResulti=RResulti;for(inti=0;i32;i+)RResulti=tempi;for(inti=0;i32;i+)L0i=LResulti;R0i=RResulti;/*coutzuoendl;for(inti=0;i32;i+)cout(int)LResulti;if(i+1)%8=0)co
18、utendl;cout右边endl;for(inti=0;i32;i+)cout(int)RResulti;if(i+1)%8=0)coutendl;*/LResultj=RResultj;for(intj=0;j32;j+)RResultj=tempj;for(inti=0;i32;i+)L0i=LResulti;R0i=RResulti;/*cout左边endl;for(inti=0;i32;i+)cout(int)LResulti;if(i+1)%8=0)coutendl;cout右边endl;for(inti=0;i32;i+)cout(int)RResulti;if(i+1)%8=0
19、)coutendl;*/生成48位子密钥voidGetCD48(ElemTypeC28,ElemTypeD28,ElemTypeSecret48)ElemTypetemp56;for(inti=0;i28;i+)tempi=Ci;for(inti=28;i56;i+)tempi=Ci;for(inti=0;i48;i+)Secreti=tempCutEXi;/48位明文与子密钥进行异或/*ExpandMsg4848位明文，Secret4848位密钥，Result48异或结果*/voidXOR(ElemTypeExpandMsg48,ElemTypeSecret48,ElemTypeResult
20、48)for(inti=0;i48;i+)Resulti=ExpandMsgiSecreti;/S盒四位输出voidgetSOut(ElemTypeResult48,ElemTypeSout32)introw;intcol;ElemTypetemp6;for(inti=0;i8;i+)for(intj=0;j6;j+)tempj=Resulti*6+j;row=temp0*2+temp5;col=temp1*8+temp2*4+temp3*2+temp4*1;intk=Sirowcol%2;Souti*4+3=k;Souti*4+2=k%2;Souti*4+1=(k%2)%2;Souti*4=
21、(k%2)%2)%2;/直接置换voidDirExchange(ElemTypeSout32,ElemTypeDirOut32)for(inti=0;i32;i+)DirOuti=SoutDIREXi-1;/左右异或得到RivoidXORLR(ElemTypeDirOut32,ElemTypeLeft32,ElemTypeResult32)for(inti=0;i32;i+)Resulti=DirOutiLefti;void_tmain(intargc,_TCHAR*argv)ElemTypebit64;ElemTypech8;ElemTypeDisorder64;ElemTyperight32;ElemTypeleft32;ElemTypeexpand48;ElemTypeSECRET56=1,1,0,1,0,0,1,1,1,0,1,0,1,1,0,0,0,0,1,0,1,1,0,0,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,1,1,1,0,0,0,1,0,0,1,1,1,0,1;/获取C0与D0ElemTypeC28;ElemTyp
