1#include <stdint.h> 2#include <stdlib.h> 3#include <unistd.h> 4 5struct expanded_key { 6 uint32_t l[16], r[16]; 7}; 8 9void __des_setkey(const unsigned char *key, struct expanded_key *ekey); 10void __do_des(uint32_t l_in, uint32_t r_in, 11 uint32_t *l_out, uint32_t *r_out, 12 uint32_t count, uint32_t saltbits, const struct expanded_key *ekey); 13 14 15static struct expanded_key __encrypt_key; 16 17void setkey(const char *key) 18{ 19 unsigned char bkey[8]; 20 int i, j; 21 22 for (i = 0; i < 8; i++) { 23 bkey[i] = 0; 24 for (j = 7; j >= 0; j--, key++) 25 bkey[i] |= (uint32_t)(*key & 1) << j; 26 } 27 28 __des_setkey(bkey, &__encrypt_key); 29} 30 31void encrypt(char *block, int edflag) 32{ 33 struct expanded_key decrypt_key, *key; 34 uint32_t b[2]; 35 int i, j; 36 char *p; 37 38 p = block; 39 for (i = 0; i < 2; i++) { 40 b[i] = 0; 41 for (j = 31; j >= 0; j--, p++) 42 b[i] |= (uint32_t)(*p & 1) << j; 43 } 44 45 key = &__encrypt_key; 46 if (edflag) { 47 key = &decrypt_key; 48 for (i = 0; i < 16; i++) { 49 decrypt_key.l[i] = __encrypt_key.l[15-i]; 50 decrypt_key.r[i] = __encrypt_key.r[15-i]; 51 } 52 } 53 54 __do_des(b[0], b[1], b, b + 1, 1, 0, key); 55 56 p = block; 57 for (i = 0; i < 2; i++) 58 for (j = 31; j >= 0; j--) 59 *p++ = b[i]>>j & 1; 60} 61