分组密码DES加密C++实现

#include"DES.h" void IpDisPlay(int M[]) { int IPTable[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 };//初始ip置换表 for (int i = 0;i < 64;i++) { int temp = M[i]; M[i] = M[IPTable[i] - 1]; M[IPTable[i] - 1] = temp; } } void IpRDisPlay(int M[]) { int IPTable[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 };//逆初始ip置换表 for (int i = 0;i < 64;i++) { int temp = M[i]; M[i] = M[IPTable[i] - 1]; M[IPTable[i] - 1] = temp; } } void E(int R[],int E[]) { int ETable[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 };//E盒 for (int i = 0;i < 48;i++) { E[i] = R[ETable[i] - 1]; } } void BinaryChange(int a[],int n)//十进制转为4位二进制 { int j = 3; while (n) { a[j] = n % 2; n = n / 2; j--; } } //S盒变换 void S(int R[],int Res[]) { int S[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} } }; int Snum[8]; int i = 0,k = 0; for (int j = 0;j < 8;j++) { int x = 2 * R[i] + R[i + 5]; int y = 8 * R[i + 1] + 4 * R[i + 2] + 2 * R[i + 3] + R[i + 4]; i = i + 6; Snum[j] = S[j][x][y]; int a[4] = {0,0,0,0}; BinaryChange(a,Snum[j]); for (int l = 0;l < 4;l++) { Res[k] = a[l]; k++; } } } void PDisplay(int M[]) { int IPTable[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};//p盒置换表 for (int i = 0;i <32;i++) { int temp = M[i]; M[i] = M[IPTable[i] - 1]; M[IPTable[i] - 1] = temp; } } //循环左移 void MoveLeft(int D[], int n) { int Res[sizeof(D) / sizeof(D[0])]; for (int i = 0;i < sizeof(D) / sizeof(D[0]);i++) { if (i + n >= sizeof(D) / sizeof(D[0])) { Res[i] = D[i + n - sizeof(D) / sizeof(D[0])]; } else { Res[i] = D[i + n]; } } memcpy(D, Res, sizeof(Res)); } //密钥生成 void SecretKey(int Key[], int Keys[][48]) { int Dp1[56] = { 57,49,41,33,25,17,9,1,58,50,42,34,26,18,10,2,59,51,43,35,27,19,11,3,60,52,44,36,63,55,47,39,31,23,15,7,62,54,46,38,30,22,14,6,61,53,45,37,29,21,13,5,28,20,12,4 }; int Dp2[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 }; int circle[16] = { 1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1 }; //选择置换1 int Keyy[56],Keyy2[56]; for (int i = 0;i <56;i++) { Keyy[i] = Key[Dp1[i]-1]; } int* C = new int[28]; int* D = new int[28]; for (int i = 0;i < 56;i++) { if (i < 28) { C[i] = Keyy[i]; } else { D[i - 28] = Keyy[i]; } } //16圈循环得到16组密钥keys for (int i = 0; i < 16;i++) { MoveLeft(C, circle[i]); MoveLeft(D, circle[i]); for (int j = 0;j < 56;j++) { if (j < 28) { Keyy2[j] = C[j]; } else { Keyy2[j] = D[j - 28]; } } for (int j = 0;j < 48;j++) { Keys[i][j] = Keyy2[Dp2[j]-1]; } } delete[] C; delete[] D; } //des加密 void Des(int M[], int Key[]) { IpDisPlay(M); int L[32]; int R[32]; int keys[16][48]; int Res[32]; int temp[32]; int temp2[32]; for (int i = 0;i < 64;i++) { if (i < 32) { L[i] = M[i]; } else { R[i - 32] = M[i]; } } //生成密钥 SecretKey(Key, keys); //16圈 for (int i = 0;i < 16;i++) { //E盒 E(R, Res); for (int j = 0;j < 48;j++) { Res[j] = Res[j] ^ keys[i][j]; } S(Res, temp); PDisplay(temp); for (int j = 0;j < 32;j++) { temp2[j] = R[j]; } //R1 = L0^f(R0,k1); for (int j = 0;j < 48;j++) { R[j] = L[j] ^ temp[j]; } //L1 = R0 for (int j = 0;j < 32;j++) { L[j] = temp2[j]; } } for (int i = 0;i < 64;i++) { if (i < 32) { M[i] = R[i]; } else { M[i] = L[i-32]; } } IpRDisPlay(M); }