密码学实验三-DES算法的实现

./实验三用DES实现对数据的加解密一、实验目的1.用DES加密方法实现对明文的加密2．用DES解密加密后的密文二、实验内容1、给定八字节明文,输入8位密钥对明文加密2、用同一个密钥对加密的密文解密的到原来的明文三、实验原理实验步骤〔包括流程图、功能模块〕[实验原理]1、DES算法把64位的明文输入块变为64位的密文输出块,它所使用的密钥也是64位,其功能是把输入的64位数据块按位重新组合,并把输出分为L0、R0两部分,每部分各长32位,其置换规则见下表：58,50,12,34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7,2.将输入的第58位换到第一位,第50位换到第2位,...,依此类推,最后一位是原来的第7位。L0、R0则是换位输出后的两部分,L0是输出的左32位,R0是右32位,例：设置换前的输入值为D1D2D3D64,则经过初始置换后的结果为：L0=D550...D8；R0=D57D49...D7。经过26次迭代运算后。得到L16、R16,将此作为输入,进行逆置换,即得到密文输出。逆置换正好是初始置的逆运算,例如,第1位经过初始置换后,处于第40位,而通过逆置换,又将第40位换回到第1位,其逆置换规则如下表所示：40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,42,10,50,18,5826,33,1,41,9,49,17,57,25,3.DES算法的解密过程是一样的,区别仅仅在於第一次迭代时用子密钥K15,第二次K14、,最后一次用K0,算法本身并没有变化。[算法流程图][功能模块]输入明文：voidDES::SetMsg<char*_msg,int_length>{if<_length>8> {return; }for<inti=0;i<_length;i++> { msg[i]=_msg[i]; }//转换成二进制 Char2Bit<msg,bmsg,8>;};输入密钥：voidDES::SetKey<char*_key,int_length>{if<_length>8> {return; }for<inti=0;i<_length;i++> { key[i]=_key[i]; }//转成二进制 Char2Bit<key,bkey,8>;};各种置换：voidDES::InitSwap<boolin[64]>{//打乱for<inti=0;i<32;i++> { lmsgi[i]=in[ip[i]-1]; rmsgi[i]=in[ip[i+32]-1]; }};////初始逆置换函数voidDES::InitReSwap<boolout[64]>{//组合成64数组booltemp[64];for<inti=0;i<32;i++> { temp[i]=rmsgi[i]; temp[32+i]=lmsgi[i]; }//按照逆ip矩阵for<inti=0;i<64;i++> {out[i]=temp[back_ip[i]-1]; }};//voidDES::SubKeyOff<bool*_subkey,int_off>{booltemp;for<inti=0;i<_off;i++> { temp=_subkey[0];for<inti=0;i<27;i++> {_subkey[i]=_subkey[i+1]; }_subkey[27]=temp; }};S盒处理：voidDES::DealSBox<boolin[48],boolout[32]>{bool_in[6],_out[4];//8个盒子for<inti=0;i<8;i++> {//提取盒子for<intj=0;j<6;j++> { _in[j]=in[i*6+j]; }//压缩 _DealSBox<_in,_out,i>;//放进out数组for<intjj=0;jj<4;jj++> {out[i*4+jj]=_out[jj]; } }};加密函数：voidDES::CrypteFunction<boolin[32],intisubkey,boolout[32]>{//e操作booltemp1[48]; EOperation<in,temp1>;booltemp2[48]; Mode2Add<temp1,<bool*>subkey[isubkey],temp2,48>;//ok//盒子压缩booltemp3[48]; DealSBox<temp2,temp3>;//置换运算p POperation<temp3,out>;};解密函数：voidDES::Decipher<>{booltemp1[32],temp2[32];//初始置换ip InitSwap<bcryptedmsg>;//16轮迭代加密for<inti=0;i<16;i++> {if<i%2==0> {//L1=R0 CopyArray<rmsgi,lmsgi1,32>;//f<R0,k0> CrypteFunction<rmsgi,15-i,temp1>;//L0+f<R0,k0> Mode2Add<lmsgi,temp1,temp2,32>;//R1=L0+f<R0,k0> CopyArray<temp2,rmsgi1,32>; }else {//L2=R1 CopyArray<rmsgi1,lmsgi,32>;//f<R1,k1> CrypteFunction<rmsgi1,15-i,temp1>;//L1+f<R1,k1> Mode2Add<lmsgi1,temp1,temp2,32>;//R2=L1+f<R1,k1> CopyArray<temp2,rmsgi,32>; } }//逆初始置换ip InitReSwap<bdecipher>;//转成字符 Bit2Char<bdecipher,decipher>;};软件使用说明〔开发环境、参数使用详细说明、实验结果+相应截图等〕[开发环境]MicrosoftVisualStudio2015MicrosoftWindows10[参数使用]char*msg;char*key;[实验结果]实验数据：六、参考资料〔书籍或网络文章〕《密码编码学与网络安全——原理与实践〔第五版〕》百度七、实验心得和总结做这次DES加解密实验前首先要充分了解其原理,在这个实验中,比较难的就是,要将明文和密钥经过初始变换和十六轮加密变换等一系列变换后才能得到置换,其中的变换步骤比较多,而且比较复杂,还要将十六进制转化为二进制,工作量比较大。附:程序源代码#include"stdafx.h"#include<iostream>#include<string.h>usingnamespacestd;classDES{private://明文charmsg[8];boolbmsg[64];//密钥charkey[8];boolbkey[64];//16个子密钥boolsubkey[16][48];//l0r0中间变量boolrmsgi[32],lmsgi[32];//第i个boolrmsgi1[32],lmsgi1[32];//第i+1个//密文boolbcryptedmsg[64];charcryptedmsg[8];//解密的结果boolbdecipher[64];chardecipher[8];private://静态常量//不允许在类内初始化//初始值换ipconststaticintip[64];//子密钥//置换选择1conststaticintc0[28];conststaticintd0[28];//循环左移表conststaticintkeyoff[16];//置换选择2conststaticintdi[48];//加密函数//e运算conststaticinte_operate[48];//sboxconststaticintsbox[8][64];//置换运算pconststaticintp_operate[32];//逆初始置换ipconststaticintback_ip[64];//位掩码conststaticcharbitmask[8];public://设置明文和密钥//_length要小于或等于8voidSetMsg<char*_msg,int_length>;voidSetKey<char*_msg,int_length>;//生产子密钥voidProduceSubKey<>;//总的的加密流程voidCrypte<>;//解密voidDecipher<>;//输出密文voidOutPutCryptedMsg<>;//二进制转成字符voidBit2Char<bool*_barray,char*_carray>;//length=64//输出解密后的明文voidOutPutDecipher<>;private://字符转成二进制,并保存到64位bool数组中voidChar2Bit<char*_carray,bool*_barray,intlength>;////二进制转成字符//voidBit2Char<bool*_barray,char*_carray>;//length=64//初始置换voidInitSwap<boolin[64]>;//初始逆置换voidInitReSwap<boolout[64]>;//循环左移voidSubKeyOff<bool*_subkey,int_off>;//e运算操作函数voidEOperation<boola[32],boolb[48]>;//模2相加//相同为0不同为1voidMode2Add<boola[],boolb[],boolc[],intlength>;//sboxvoidDealSBox<boolin[48],boolout[32]>;void_DealSBox<boolin[6],boolout[4],intbox>;//poprarationvoidPOperation<booltemp[32],boolresult[32]>;//加密函数voidCrypteFunction<boolin[32],intisubkey,boolout[32]>;//数组之间赋值voidCopyArray<boolarray1[],boolarray2[],intsize>;};usingnamespacestd;//静态常量constintDES::ip[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};constintDES::c0[28]={ 57,49,41,33,25,17,9, 1,58,50,42,34,26,18, 10,2,59,51,43,35,27, 19,11,3,60,52,44,36};constintDES::d0[28]={ 63,55,47,39,31,23,15, 7,62,54,46,38,30,22, 14,6,61,53,45,37,29, 21,13,5,28,20,12,4};constintDES::keyoff[16]={ 1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};constintDES::di[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};constintDES::e_operate[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, 28,29,30,31,32,1};constintDES::sbox[8][64]={ { 14,4,13,1,1,15,11,8,3,10,6,12,5,9,0,7, 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 }, { 13,2,8,4,6,15,11,1,10,9,13,14,5,0,12,7, 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 }};constintDES::p_operate[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};constintDES::back_ip[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, 34,2,42,10,50,18,58,26, 33,1,41,9,49,17,57,25};constcharDES::bitmask[8]={128,64,32,16,8,4,2,1};//实现函数////设置明文//voidDES::SetMsg<char*_msg,int_length>{if<_length>8> {return; }for<inti=0;i<_length;i++> { msg[i]=_msg[i]; }//转换成二进制 Char2Bit<msg,bmsg,8>;};////设置密钥//voidDES::SetKey<char*_key,int_length>{if<_length>8> {return; }for<inti=0;i<_length;i++> { key[i]=_key[i]; }//转成二进制 Char2Bit<key,bkey,8>;};////字符转成二进制voidDES::Char2Bit<char*_carray,bool*_barray,intlength>{//intindex=0;for<inti=0;i<length;i++> {for<intj=0;j<8;j++> {_barray[i*8+7-j]=<_carray[i]>>j>&1; } }};////二进制转成字符//voidDES::Bit2Char<bool*_barray,char*_carray>{chartemp;for<inti=0;i<8;i++> {//数学方法转成字符 temp=0;for<intj=0;j<8;j++> {if<_barray[i*8+j]==1> { temp|=bitmask[j]; } }//cout<<temp;_carray[i]=temp; }};////初始置换函数//okvoidDES::InitSwap<boolin[64]>{//打乱for<inti=0;i<32;i++> { lmsgi[i]=in[ip[i]-1]; rmsgi[i]=in[ip[i+32]-1]; }};////初始逆置换函数//okvoidDES::InitReSwap<boolout[64]>{//组合成64数组booltemp[64];for<inti=0;i<32;i++> { temp[i]=rmsgi[i]; temp[32+i]=lmsgi[i]; }//按照逆ip矩阵for<inti=0;i<64;i++> {out[i]=temp[back_ip[i]-1]; }};////循环左移//okvoidDES::SubKeyOff<bool*_subkey,int_off>{//有没有更好的办法???booltemp;for<inti=0;i<_off;i++> { temp=_subkey[0];for<inti=0;i<27;i++> {_subkey[i]=_subkey[i+1]; }_subkey[27]=temp; }};////生产子密钥//okvoidDES::ProduceSubKey<>{//置换选择1boolctemp[28],dtemp[28];for<inti=0;i<28;i++> { ctemp[i]=bkey[c0[i]-1]; dtemp[i]=bkey[d0[i]-1]; }boolkeytemp[56];for<inti=0;i<16;i++> {//循环左移 SubKeyOff<ctemp,keyoff[i]>; SubKeyOff<dtemp,keyoff[i]>;//合并成一个56数组for<intj=0;j<28;j++> { keytemp[j]=ctemp[j]; keytemp[28+j]=dtemp[j]; }//置换选择2for<intj=0;j<48;j++> { subkey[i][j]=keytemp[di[j]-1]; } }};////e运算//okvoidDES::EOperation<boola[32],boolb[48]>{for<inti=0;i<48;i++> {b[i]=a[e_operate[i]-1]; }};////模2想加//okvoidDES::Mode2Add<boola[],boolb[],boolc[],intlength>{for<inti=0;i<length;i++> {if<a[i]==b[i]> {c[i]=0; }else {c[i]=1; } }};////sbox处理//okvoidDES::DealSBox<boolin[48],boolout[32]>{bool_in[6],_out[4];//8个盒子for<inti=0;i<8;i++> {//提取盒子for<intj=0;j<6;j++> { _in[j]=in[i*6+j]; }//压缩 _DealSBox<_in,_out,i>;//放进out数组for<intjj=0;jj<4;jj++> {out[i*4+jj]=_out[jj]; } }};////_dealsbox//okvoidDES::_DealSBox<boolin[6],boolout[4],intbox>{intraw,col; raw=in[0]*2+in[5];//转换成十进制行 col=in[1]*2*2*2+in[2]*2*2+in[3]*2+in[4];//列intresult=sbox[box][raw*16+col];//转成二进制for<inti=3;i>=0;i--> {out[i]=<result>><3-i>>&1; }};////p操作//okvoidDES::POperation<booltemp[32],boolresult[32]>{for<inti=0;i<32;i++> {result[i]=temp[p_operate[i]-1]; }};////加密函数//isubkey表明用那个子密钥加密okvoidDES::CrypteFunction<boolin[32],intisubkey,boolout[32]>{//e操作booltemp1[48]; EOperation<in,temp1>;booltemp2[48]; Mode2Add<temp1,<bool*>subkey[isubkey],temp2,48>;//ok//盒子压缩booltemp3[48]; DealSBox<temp2,temp3>;//置换运算p POperation<temp3,out>;};////des加密流程voidDES::Crypte<>{//直接用bmsg明文//直接用cryptedmsg存放密文booltemp1[32],temp2[32];//初始置换ip InitSwap<bmsg>;//16轮迭代for<inti=0;i<16;i++> {if<i%2==0> {//L1=R0 CopyArray<rmsgi,lmsgi1,32>;//f<R0,k0> CrypteFunction<rmsgi,i,temp1>;//L0+f<R0,k0> Mode2Add<lmsgi,temp1,temp2,32>;//R1=L0+f<R0,k0> CopyArray<temp2,rmsgi1,32>; }else {//L2=R1 CopyArray<rmsgi1,lmsgi,32>;//f<R1,k1> CrypteFunction<rmsgi1,i,temp1>;//L1+f<R1,k1> Mode2Add<lmsgi1,temp1,temp2,32>;//R2=L1+f<R1,k1> CopyArray<temp2,rmsgi,32>; } }//逆初始置换ip InitReSwap<bcryptedmsg>;//转成字符 Bit2Char<bcryptedmsg,cryptedmsg>;};////数组赋值voidDES::CopyArray<boolcontent[],boolempty[],intsize>{for<inti=0;i<size;i++> {empty[i]=content[i]; }};////解密v