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1、用C语言实现DES加密与解密 #include int 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 }; int IP_1[64] = { 40,8,48,16,56,
2、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 E[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, 16,17,18,1
3、9,20,21, 20,21,22,23,24,25, 24,25,26,27,28,29, 28,29,30,31,32,1 }; int P[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 };19,11,3,60,52,44,36, 63,55,47,39,31,23,15, 7,62,54,46,38,30,22, 14
4、,6,61,53,45,37,29, 21,13,5,28,20,12,4}, PC2[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}; Char_to_Int(in,Msg_Int,8);//正确O_to_B(Msg_Int,Msg_Bin,8);//正确cout<5、_Bin,Msg_Bin_PC1,PC1,56); Divide(Msg_Bin_PC1,C[0],D[0],56); for(i=0;i<16;i++) { if(i==0) {RLC1(C[i],C[i+1],28); RLC1(D[i],D[i+1],28); } else if(i==1) { RLC1(C[i],C[i+1],28); RLC1(D[i],D[i+1],28); } else if(i==8) { RLC1(C[i],C[i+1],28); RLC1(D[i],D[i+1],28); } else if(i==15) {
6、RLC1(C[i],C[i+1],28); RLC1(D[i],D[i+1],28); } else { RLC2(C[i],C[i+1],28); RLC2(D[i],D[i+1],28); Combine(C[i+1],D[i+1],Key_Bin,56); Convert(Key_Bin,out[i],PC2,48); } } //生成子密钥正确void S_box(int in[],int out[]) { int i; int SBox[8][64] ={ { 14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7,
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
8、}, { 10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8, 13,7,0,9,3,4,6,10
