#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/param.h>
#include "DESSupport.h"
#ifndef USE_CRYPT
#include <openssl/des.h>
#endif
static u_char Get7Bits(const unsigned char *input, int startBit)
{
register unsigned int word;
word = (unsigned)input[startBit / 8] << 8;
word |= (unsigned)input[startBit / 8 + 1];
word >>= 15 - (startBit % 8 + 7);
return word & 0xFE;
}
static void MakeKey(const unsigned char *key, unsigned char *des_key)
{
des_key[0] = Get7Bits(key, 0);
des_key[1] = Get7Bits(key, 7);
des_key[2] = Get7Bits(key, 14);
des_key[3] = Get7Bits(key, 21);
des_key[4] = Get7Bits(key, 28);
des_key[5] = Get7Bits(key, 35);
des_key[6] = Get7Bits(key, 42);
des_key[7] = Get7Bits(key, 49);
#ifndef USE_CRYPT
des_set_odd_parity((des_cblock *)des_key);
#endif
}
#ifdef USE_CRYPT
static void Expand(unsigned char *in, unsigned char *out)
{
int j, c;
int i;
for(i = 0; i < 64; in++){
c = *in;
for(j = 7; j >= 0; j--)
*out++ = (c >> j) & 01;
i += 8;
}
}
static void Collapse(unsigned char *in, unsigned char *out)
{
int j;
int i;
unsigned int c;
for (i = 0; i < 64; i += 8, out++) {
c = 0;
for (j = 7; j >= 0; j--, in++)
c |= *in << j;
*out = c & 0xff;
}
}
void
DesEncrypt(const unsigned char *clear, const unsigned char *key,
unsigned char *cipher)
{
u_char des_key[8];
u_char crypt_key[66];
u_char des_input[66];
MakeKey(key, des_key);
Expand(des_key, crypt_key);
setkey(crypt_key);
Expand(clear, des_input);
encrypt(des_input, 0);
Collapse(des_input, cipher);
}
#else
void
DesEncrypt(const unsigned char * clear, const unsigned char * key,
unsigned char * cipher)
{
des_cblock des_key;
des_key_schedule key_schedule;
MakeKey(key, des_key);
des_set_key(&des_key, key_schedule);
des_ecb_encrypt((des_cblock *)clear, (des_cblock *)cipher, key_schedule, 1);
}
#endif