sdes.cpp

来自「各种加密算法的集合」· C++ 代码 · 共 50 行

#include <dos.h> 
#include <stdio.h> 
#include <stdlib.h> 
#include <graphics.h> 
#include <string.h> 

/* initial permutation IP */ 
static byte ip[] = { 
2, 6, 3, 1, 4, 8, 5, 7 
}; 

/* final permutation IP^-1 */ 
static byte fp[] = { 
4, 1, 3, 5, 7, 2, 8, 6 
}; 
/* expansion operation matrix */ 
static byte ei[] = { 
4, 1, 2, 3, 2, 3, 4, 1 
}; 
/* The (in)famous S-boxes */ 
static byte sbox[2][16] = { 
/* S1 */ 
1, 0, 3, 2, 3, 2, 1, 0, 0, 2, 1, 3, 3, 1, 3, 2, 

/* S2 */ 
0, 1, 2, 3, 2, 0, 1, 3, 3, 0, 1, 0, 2, 1, 0, 3 
}; 

/* 32-bit permutation function P used on the output of the S-boxes */ 
static byte p32i[] = { 
2, 4, 3, 1 
}; 
#endif 

/* permuted choice table (key) */ 
static const byte pc1[] = { 
3, 5,2,7,4,10,1,9,8,6 
}; 

/* number left rotations of pc1 */ 
static const byte totrot[] = { 
1,2 
}; 

/* permuted choice key (table) */ 
static const byte pc2[] = { 
6,3,7,4,8,5,10,9 
}; 

/* End of DES-defined tables */