수다닷컴

암호화 과정을 c언어로 소스파일 만들고 싶은데요 s-des 입니다.
s-des 과정을 짠 소스 인데요 에러가 안풀려서....

질문 내용 :

#include stdio.h
#include stdlib.h
#include string.h
#include time.h
#define key_size 10
#define block_size 8
#define word2byte(w,b)

b[1] = w 8;
b[0] = w;
typedef unsigned char byte;
typedef unsigned short word;
void
sdes_random_key_generation(byte* pbkey)
{
const word wmod = (1 9);
word wkey = 0;
/* 1. initialize random seed */
srand(time(0));
/* 2. generate a random value */
wkey = rand() % wmod;
/* 3. move a word to two-byte array */
word2byte(wkey, pbkey);
#ifdef __debug
printf([1]%02x%02x\n, pbkey[1], pbkey[0]);
#endif
return;
}
void
sdes_p10(byte* pbkey)
{
byte pbpermkey[2] = {0};
byte temp = {0};
#ifdef __debug
printf([2]%02x%02x\n, pbkey[1], pbkey[0]);
#endif
temp = pbkey[0] & 0x80;
pbpermkey[1] = pbpermkey[1] | (temp 6); // 3
temp = pbkey[0] & 0x20;
pbpermkey[1] = pbpermkey[1] | (temp 5); // 5
temp = pbkey[1] & 0x01;
pbpermkey[0] = pbpermkey[0] | (temp 7); // 2
temp = pbkey[0] & 0x08;
pbpermkey[0] = pbpermkey[0] | (temp 3); // 7
temp = pbkey[0] & 0x40;
pbpermkey[0] = pbpermkey[0] | (temp 1); // 4
temp = pbkey[0] & 0x01;
pbpermkey[0] = pbpermkey[0] | (temp 4); // 10
temp = pbkey[1] & 0x02;
pbpermkey[0] = pbpermkey[0] | (temp 2); // 1
temp = pbkey[0] & 0x02;
pbpermkey[0] = pbpermkey[0] | (temp 1); // 9
temp = pbkey[0] & 0x04;
pbpermkey[0] = pbpermkey[0] | (temp 1); // 8
temp = pbkey[0] & 0x10;
pbpermkey[0] = pbpermkey[0] | (temp 4); // 6
pbkey[1] = pbpermkey[1];
pbkey[0] = pbpermkey[0];
#ifdef __debug
printf([3]%02x%02x\n, pbkey[1], pbkey[0]);
#endif
return;
}
void
sdes_ls1(byte* pbdata)
{
return;
}

void
sdes_p8(const byte lk, const byte rk, byte* k1)
{
return;
}
/*************************************************************************
* be careful at pbkey is 2-byte, but pbk1 and pbk2 are 1 byte
*************************************************************************
*/
void
sdes_key_generation(byte* pbkey, byte* pbk1, byte* pbk2)
{
/* 1. generate a random key for encryption and decryption */
sdes_random_key_generation(pbkey);
/* 2. p10 */
sdes_p10(pbkey);
/* 3. ls1 */
byte lk = 0, rk = 0;
lk = (pbkey[1] 3) | (pbkey[0] 5);
rk = pbkey[0] & 0x1f;
sdes_ls1(&lk);
sdes_ls1(&rk);
/* 4. p8 */
*pbk1 = 0;
sdes_p8(lk, rk, pbk1);
/* 5. ls2 */
sdes_ls1(&lk);
sdes_ls1(&rk);
/* 6. p8 */
*pbk2 = 0;
sdes_p8(lk, rk, pbk2);
return;
}
void
sdes_encryption(const byte bk1, const byte bk2, const byte bplaintext, byte* pbciphertext)
{
byte l = 0, //(bplaintext 4),
r = 0; //(bplaintext & 0x0f);
/* 1. ip
* 1 2 3 4 5 6 7 8
* 2 6 3 1 4 8 5 7
*/
byte temp = 0;
temp = temp | ((bplaintext & 0x40) 1);
temp = temp | ((bplaintext & 0x04) 4);
temp = temp | ((bplaintext & 0x20) 0);
temp = temp | ((bplaintext & 0x80) 3);
temp = temp | ((bplaintext & 0x10) 1);
temp = temp | ((bplaintext & 0x01) 2);
temp = temp | ((bplaintext & 0x08) 2);
temp = temp | ((bplaintext & 0x02) 1);
l = temp 4;
r = temp & 0x0f;
#ifdef __debug
printf(l=%02x, r=%02x\n, l, r);
#endif
/* 2. e/p */
byte bep = 0;
/* 3. s0 and s1 */
/* 4. p4 */
/* 5. sw */
/* 6. e/p */
/* 7. s0 and s1 */
/* 8. p4 */
/* 9. ip?-1} */
return;
}
void
sdes_decryption(const byte bk1, const byte bk2, const byte pbciphertext, byte* pbplaintext)
{
return;
}
int main(void){
const byte* pbplaintext = information security experiment third;
byte bkey[2] = {0};
byte bk1 = 0, bk2 = 0;
byte* pbmessage = 0;
byte* pbciphertext = 0;
int i = 0;t i = 0;
int nplaintextsize = strlen(pbplaintext);
byte test = 0xb5;
/* key generation */
sdes_key_generation(bkey, &bk1, &bk2);
/* encryption */
pbciphertext = (byte *)malloc(nplaintextsize);
if (0 == pbciphertext)
return -1;
memset(pbciphertext, 0, nplaintextsize);
for (i = 0; i nplaintextsize; i++) {
sdes_encryption(bk1, bk2, pbplaintext[i], &pbciphertext[i]);
}
/* decryption */
pbmessage = (byte *)malloc(nplaintextsize);
if (0 == pbmessage)
return -1;
memset(pbmessage, 0, nplaintextsize);
for (i = 0; i nplaintextsize; i++) {
sdes_decryption(bk1, bk2, pbciphertext[i], &pbmessage[i]);
}
/* compare two results */
if (0 != memcmp(pbplaintext, pbmessage, nplaintextsize)) {
printf(decryption failure\n);
return -1;
}
printf(decryption ok!\n);
return 1;
}

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