对称密码之DES密码

#include <stdio.h> #include <stdlib.h> #include<string.h> int IP_Table[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 }; int E_Table[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}; int P_Table[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 }; int IPR_Table[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 }; int PC1_Table[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 PC2_Table[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 S_Box[8][4][16] = { // 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 }; void Xor(int *INA, int *INB, int len) { int i; for (i = 0; i<len; i++) { *(INA + i) = *(INA + i) ^ *(INB + i); } }; void IP(const int input[64], int output[64], int table[64]) { int i=0 ; for (i = 0; i<64; i++) { output[i] = input[table[i] - 1]; } }; void E(const int input[32], int output[48], int table[48]) { int i; for (i = 0; i<48; i++) { output[i] = input[table[i] - 1]; } }; void P(const int input[32], int output[32], int table[32]) { int i; for (i = 0; i<32; i++) { output[i] = input[table[i] - 1]; } }; void IPR(const int input[64], int output[64], int table[64]) { int i; for (i = 0; i<64; i++) { output[i] = input[table[i] - 1]; } }; void PC_1(const int input[64], int output[56], int table[56]) { int i; for (i = 0; i<56; i++) { output[i] = input[table[i] - 1]; } }; void PC_2(const int input[56], int output[48], int table[48]) { int i; for (i = 0; i<48; i++) { output[i] = input[table[i] - 1]; printf("%d",output[i]); } printf("\n"); }; static void S(const int input[48], int output[32], int table[8][4][16]) { int i,j = 0; int x,y = 0; int num[8]={0}; int number[8][4]={0}; for (i = 0; i<48; i = i + 6) { x=input[i]*2+input[i+5]*1; y=input[i+1]*8+input[i+2]*4+input[i+3]*2+input[i+4]*1; num[j]=table[j][x][y]; j=j+1; } for (j = 0; j<8; j++) { for (i = 0; i<4; i++) { number[j][i]=num[j]%2; num[j]=num[j]/2; if(num[j]==0) { break; } } } for (j = 0; j<8; j++) { for (i = 0; i<4; i++) { output[j*4+i]=number[j][3-i]; } } }; void F_func(int input[32], int output[32], int subkey[48]) { int len = 48; int temp[48] = { 0 }; int temp_1[32] = { 0 }; E(input, temp, E_Table); Xor(temp, subkey, len); S(temp, temp_1, S_Box); P(temp_1, output, P_Table); }; void SHL(const int input[28], int output[28], int leftCount) { int i; int len = 28; for (i = 0; i<len; i++) { output[i] = input[(i + leftCount) % len]; } }; void subKey_fun(const int input[64], int Subkey[16][48]) { int loop = 1, loop_2 = 2; int i, j; int c[28], d[28]; int pc_1[56] = {0}; int pc_2[16][56] = {0}; int shl_c[16][28] = {0}; int shl_d[16][28] = {0}; PC_1(input, pc_1, PC1_Table); for (i = 0; i<28; i++) { c[i] = pc_1[i]; d[i] = pc_1[i + 28]; } int leftCount = 0; for (i = 1; i<17; i++) { if (i == 1 || i == 2 || i == 9 || i == 16) { leftCount += loop; SHL(c, shl_c[i - 1], leftCount); SHL(d, shl_d[i - 1], leftCount); } else { leftCount += loop_2; SHL(c, shl_c[i - 1], leftCount); SHL(d, shl_d[i - 1], leftCount); } } for (i = 0; i<16; i++) { for (j = 0; j<28; j++) { pc_2[i][j] = shl_c[i][j]; pc_2[i][j + 28] = shl_d[i][j]; } } for (i = 0; i<16; i++) { PC_2(pc_2[i], Subkey[i], PC2_Table); } }; void DES_Efun(int input[64], int key_64[64], int output[64]) { int i=0,j=0,k=0; int ip[64] = {0}; int output_1[64] = {0}; int subkeys[16][48]; int l[16][32], r[16][32]; subKey_fun(key_64, subkeys); IP(input, ip, IP_Table); for (i = 0; i<32; i++) { l[0][i] = ip[i]; r[0][i] = ip[32 + i]; } for (j = 1; j<=16; j++) { for (k = 0; k<32; k++) { l[j][k] = r[j - 1][k]; } F_func(r[j - 1], r[j], subkeys[j - 1]); Xor(r[j], l[j - 1], 32); } for (i = 0; i<32; i++) { output_1[i] = l[16][i]; output_1[32 + i] = r[16][i]; } IPR(output_1, output, IPR_Table); }; void DES_Dfun(int input[64], int key_64[64], int output[64]) { int i=0,j=0,k=0; int ip[64] = {0}; int output_1[64] = {0}; int subkeys[16][48]; int l[16][32], r[16][32]; subKey_fun(key_64, subkeys); IP(input, ip, IP_Table); for (i = 0; i<32; i++) { l[0][i] = ip[i]; r[0][i] = ip[32 + i]; } for (j = 1; j<=16; j++) { for (k = 0; k<32; k++) { l[j][k] = r[j - 1][k]; } F_func(r[j - 1], r[j], subkeys[15-j]); Xor(r[j], l[j - 1], 32); } for (i = 0; i<32; i++) { output_1[i] = l[16][i]; output_1[32 + i] = r[16][i]; } IPR(output_1, output, IPR_Table); }; void encrypt() { int i=0; int exit[64] = {0}; int enter[64] = {0}; int key_64[64] = {0}; printf("请输入明文(64bit)\n"); for (i = 0; i<64; i++) { scanf("%c",&enter[i]); } while(getchar()!='\n'); printf("请输入秘钥(64bit)\n"); for (i = 0; i<64; i++) { scanf("%c",&key_64[i]); } printf("\n"); DES_Efun(enter,key_64,exit); printf("生成的密文:\n"); for (i = 0; i<64; i++) { printf("%d", exit[i]); } } void decrypt() { int i=0; int exit[64] = {0}; int enter[64] = {0}; int key_64[64] = {0}; printf("请输入密文(64bit)\n"); for (i = 0; i<64; i++) { scanf("%c",&enter[i]); enter[i]=enter[i]-48; } while(getchar()!='\n'); printf("请输入秘钥(64bit)\n"); for (i = 0; i<64; i++) { scanf("%c",&key_64[i]); key_64[i]=key_64[i]-48; } printf("\n"); DES_Dfun(enter,key_64,exit); printf("还原的明文:\n"); for (i = 0; i<64; i++) { printf("%d", exit[i]); } } int main(int argc, char *argv[]) { while(1) { int n=0; printf("**************************************\n"); printf("**** 按1进入DES密码加密 ****\n"); printf("**** 按2进入DES密码解密 ****\n"); printf("**** 按3结束菜单 ****\n"); printf("**************************************\n"); printf("请先输入1或2："); scanf("%d",&n); while(getchar()!='\n'); if(n==1) encrypt(); else if(n==2) decrypt(); else if(n==3) break; else { printf("the wrong number!!!\n"); } } fflush stdin; return 0; }