DES源代码C语言实现(简洁易懂)

#include/* 初始置换表IP */int IP_Table64 = 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, 56,48,40,32,24,16,8,0, 58,50,42,34,26,18,10,2, 60,52,44,36,28,20,12,4, 62,54,46,38,30,22,14,6;/* 逆初始置换表IP */int IP_1_Table64 = 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, 32,0,40,8,48,16,56,24;/* 扩充置换表E */int E_Table48 = 31, 0, 1, 2, 3, 4, 3, 4, 5, 6, 7, 8, 7, 8,9,10,11,12, 11,12,13,14,15,16, 15,16,17,18,19,20, 19,20,21,22,23,24, 23,24,25,26,27,28, 27,28,29,30,31,0;/* 置换函数P */int P_Table32 = 15,6,19,20,28,11,27,16, 0,14,22,25,4,17,30,9, 1,7,23,13,31,26,2,8, 18,12,29,5,21,10,3,24;/* S盒 */int S8416 =/* S1 */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,/* S2 */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,/* S3 */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,/* S4 */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,/* S5 */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,/* S6 */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,/* S7 */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,/* S8 */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;/* 置换选择1 */int PC_156 = 56,48,40,32,24,16,8, 0,57,49,41,33,25,17, 9,1,58,50,42,34,26, 18,10,2,59,51,43,35, 62,54,46,38,30,22,14, 6,61,53,45,37,29,21, 13,5,60,52,44,36,28, 20,12,4,27,19,11,3;/* 置换选择2 */int PC_248 = 13,16,10,23,0,4, 2,27,14,5,20,9,22,18,11,3,25,7,15,6,26,19,12,1, 40,51,30,36,46,54,29,39,50,44,32,47,43,48,38,55,33,52,45,41,49,35,28,31;/把8X6的数组变成一个一维数组void change1(int E86,int r48)int i,j;for(i=0;i8;i+)for(j=0;j6;j+)ri*6+j = Eij;/把一维数组变成8X6的矩阵void change2(int r48,int E86)int i,j;for(i=0;i8;i+)for(j=0;j6;j+)Eij= ri*6+j;/输入16进制明文void input(int M88) int i,j,k;char c16;int s16,d64,a164; printf(请输入16位16进制数：);for(i=0;i16;i+)scanf(%c,&ci); for(i=0;i=48&ci=A&ci=a&ci=z) si=ci-87; else puts(errorn); return; /把16进制数组c转化为二进制数： k=0; while(k=0;j-) akj=sk%2; sk/=2; k+; /把a164转化成a88类型数组for(k=0;k16;k+) for(j=0;j4;j+) dk*4+j = akj; for(i=0;i8;i+) for(j=0;j8;j+) Mij = di*8+j; /*/打印密文二进制数组for(i=0;i8;i+) for(j=0;j8;j+) printf(%2d,Mij); printf(n);*/*初始置换*/void Startedexchange(int MW88,int temp88)int i,j,a64,b64;for(i=0;i8;i+) for(j=0;j8;j+) ai*8+j = MWij;for(i=0;i64;i+)bi = aIP_Tablei;for(i=0;i8;i+)for(j=0;j8;j+)tempij = bi*8+j;/*for(i=0;i8;i+) for(j=0;j8;j+) printf(%2d,tempij); printf(n);*/*生成秘钥*/void bornkey(int MY88,int n,int key 48) int i,j,m;int tem,tem2;int k64,k156;int a87;int c28,d28;int list16=1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1;for(i=0;i8;i+)for(j=0;j8;j+)ki*8+j = MYij;for(i=0;i8;i+)for(j=0;j7;j+)aij = kPC_1i*7+j;/*for(i=0;i8;i+)for(j=0;j7;j+)printf(%d,aij);printf(n);*/c0,d0for(i=0;i4;i+)for(j=0;j7;j+) ci*7+j = aij;for(i=4;i8;i+)for(j=0;j7;j+) di*7+j-28 = aij;/确定左移位数m = 0;for(i=0;in;i+)m+=listi;/循环左移处理while(m) tem=c0; for(i=0;i27;i+) ci = ci+1; c27 = tem; tem2 = d0; for(i=0;i27;i+) di = di+1; d27 = tem2; m-;/*for(i=0;i28;i+)printf(%d,di);printf(n);*/合并for(i=0;i28;i+)k1i = ci;for(i=0;i28;i+)k128+i = di;/置换选择2for(i=0;i48;i+)keyi = k1PC_2i;/第一次异或void firstXOR(int key48,int R48,int k248)int i;for(i=0;i48;i+) if(Ri!=keyi) k2i = 1; else k2i = 0;/S盒压缩变换void Schange(int k248,int k332)int i,h,l,a,temp,k,m,j; int b86;int num4; change2(k2,b); m=0;/printf(n); for(i=0;i=0)numk=0;k-;for(j=0;j4;j+)k3m = numj;m+; /置换运算Pvoid Pchange(int k332,int p32) int i; for(i=0;i32;i+) pi = k3P_Tablei; /拓展变换void extension(int a32,int b48)int i;for(i=0;i48;i+) bi = aE_Tablei; void feistel(int R32, int key48,int p32)int b48,k248,k332;extension(R,b);firstXOR(key,b,k2);/key后半部分出现问题Schange(k2,k3);Pchange(k3,p);/第二次异或void SecondXOR(int L32,int p32,int R132)int i;for(i=0;i32;i+)if(Li!=pi)R1i = 1;elseR1i = 0;/*把明文分成两部分32+32*/void divideLR(int temp88,int L32,int R32)int i,j;for(i=0;i4;i+)for(j=0;j8;j+)Li*8+j = tempij; for(i=0;i4;i+)for(j=0;j8;j+)Ri*8+j = tempi+4j;void exchange(int R32,int L32) int i; for(i=0;i32;i+) Li = Ri; /逆初始置换void restartexchange(int L32,int R32,int secret64) int a64; int i; for(i=0;i32;i+) ai = Li; for(i=0;i32;i+) a32+i = Ri; for(i=0;i64;i+) secreti = aIP_1_Tablei; / 将二进制 数转化为16进制void BtoOX (int a64, char b 16)int i,j,k,n,r;n=0;for(i=0;i16;i+)k=8;r=0;for(j=1;j5;j+)r+=an*k;k=k/2;n+;if(r10)bi=r+48;elsebi=r+55;void main()int i,j,a;int MW88;/密文int MY88;/秘钥int temp88;/过渡数组int L32;/左边加密部分int R32;/右边加密部分int R132;int key48;/生成的秘钥int p32;int secret64;/密文二进制表示char miwen16;printf(请输入明文：);input(MW);getchar();Startedexchange(MW,temp);divideLR(temp,L,R);printf(请输入秘钥：);input(MY);/打印密文二进制数组a =