401 lines
10 KiB
Plaintext
401 lines
10 KiB
Plaintext
/*
|
|
* $Id: cast-128.c,v 1.1 2007/07/19 06:11:48 pizon Exp $
|
|
*
|
|
* CAST-128 in C
|
|
* Written by Steve Reid <sreid@sea-to-sky.net>
|
|
* 100% Public Domain - no warranty
|
|
* Released 1997.10.11
|
|
*/
|
|
|
|
/* Adapted to the pike cryptographic toolkit by Niels Möller */
|
|
|
|
/* modified in order to use the libmcrypt API by Nikos Mavroyanopoulos
|
|
* All modifications are placed under the license of libmcrypt.
|
|
*/
|
|
|
|
/* $Id: cast-128.c,v 1.1 2007/07/19 06:11:48 pizon Exp $ */
|
|
|
|
#include <libdefs.h>
|
|
|
|
#include <mcrypt_modules.h>
|
|
#include "cast-128.h"
|
|
|
|
#define _mcrypt_set_key cast_128_LTX__mcrypt_set_key
|
|
#define _mcrypt_encrypt cast_128_LTX__mcrypt_encrypt
|
|
#define _mcrypt_decrypt cast_128_LTX__mcrypt_decrypt
|
|
#define _mcrypt_get_size cast_128_LTX__mcrypt_get_size
|
|
#define _mcrypt_get_block_size cast_128_LTX__mcrypt_get_block_size
|
|
#define _is_block_algorithm cast_128_LTX__is_block_algorithm
|
|
#define _mcrypt_get_key_size cast_128_LTX__mcrypt_get_key_size
|
|
#define _mcrypt_get_supported_key_sizes cast_128_LTX__mcrypt_get_supported_key_sizes
|
|
#define _mcrypt_get_algorithms_name cast_128_LTX__mcrypt_get_algorithms_name
|
|
#define _mcrypt_self_test cast_128_LTX__mcrypt_self_test
|
|
#define _mcrypt_algorithm_version cast_128_LTX__mcrypt_algorithm_version
|
|
|
|
#define u8 byte
|
|
#define u32 word32
|
|
|
|
#include "cast-128_sboxes.h"
|
|
|
|
/* Macros to access 8-bit bytes out of a 32-bit word */
|
|
#define U8a(x) ( (u8) (x>>24) )
|
|
#define U8b(x) ( (u8) ((x>>16)&255) )
|
|
#define U8c(x) ( (u8) ((x>>8)&255) )
|
|
#define U8d(x) ( (u8) ((x)&255) )
|
|
|
|
/* Circular left shift */
|
|
#define ROL(x, n) ( ((x)<<(n)) | ((x)>>(32-(n))) )
|
|
|
|
/* CAST-128 uses three different round functions */
|
|
#define F1(l, r, i) \
|
|
t = ROL(key->xkey[i] + r, key->xkey[i+16]); \
|
|
l ^= ((cast_sbox1[U8a(t)] ^ cast_sbox2[U8b(t)]) \
|
|
- cast_sbox3[U8c(t)]) + cast_sbox4[U8d(t)];
|
|
#define F2(l, r, i) \
|
|
t = ROL(key->xkey[i] ^ r, key->xkey[i+16]); \
|
|
l ^= ((cast_sbox1[U8a(t)] - cast_sbox2[U8b(t)]) \
|
|
+ cast_sbox3[U8c(t)]) ^ cast_sbox4[U8d(t)];
|
|
#define F3(l, r, i) \
|
|
t = ROL(key->xkey[i] - r, key->xkey[i+16]); \
|
|
l ^= ((cast_sbox1[U8a(t)] + cast_sbox2[U8b(t)]) \
|
|
^ cast_sbox3[U8c(t)]) - cast_sbox4[U8d(t)];
|
|
|
|
|
|
/***** Encryption Function *****/
|
|
|
|
WIN32DLL_DEFINE void _mcrypt_encrypt(CAST_KEY * key, u8 * block)
|
|
{
|
|
u32 t, l, r;
|
|
|
|
/* Get inblock into l,r */
|
|
l = ((u32) block[0] << 24) | ((u32) block[1] << 16)
|
|
| ((u32) block[2] << 8) | (u32) block[3];
|
|
r = ((u32) block[4] << 24) | ((u32) block[5] << 16)
|
|
| ((u32) block[6] << 8) | (u32) block[7];
|
|
/* Do the work */
|
|
F1(l, r, 0);
|
|
F2(r, l, 1);
|
|
F3(l, r, 2);
|
|
F1(r, l, 3);
|
|
F2(l, r, 4);
|
|
F3(r, l, 5);
|
|
F1(l, r, 6);
|
|
F2(r, l, 7);
|
|
F3(l, r, 8);
|
|
F1(r, l, 9);
|
|
F2(l, r, 10);
|
|
F3(r, l, 11);
|
|
/* Only do full 16 rounds if key length > 80 bits */
|
|
if (key->rounds > 12) {
|
|
F1(l, r, 12);
|
|
F2(r, l, 13);
|
|
F3(l, r, 14);
|
|
F1(r, l, 15);
|
|
}
|
|
/* Put l,r into outblock */
|
|
block[0] = U8a(r);
|
|
block[1] = U8b(r);
|
|
block[2] = U8c(r);
|
|
block[3] = U8d(r);
|
|
block[4] = U8a(l);
|
|
block[5] = U8b(l);
|
|
block[6] = U8c(l);
|
|
block[7] = U8d(l);
|
|
/* Wipe clean */
|
|
t = l = r = 0;
|
|
}
|
|
|
|
|
|
/***** Decryption Function *****/
|
|
|
|
WIN32DLL_DEFINE void _mcrypt_decrypt(CAST_KEY * key, u8 * block)
|
|
{
|
|
u32 t, l, r;
|
|
|
|
/* Get inblock into l,r */
|
|
r = ((u32) block[0] << 24) | ((u32) block[1] << 16)
|
|
| ((u32) block[2] << 8) | (u32) block[3];
|
|
l = ((u32) block[4] << 24) | ((u32) block[5] << 16)
|
|
| ((u32) block[6] << 8) | (u32) block[7];
|
|
/* Do the work */
|
|
/* Only do full 16 rounds if key length > 80 bits */
|
|
if (key->rounds > 12) {
|
|
F1(r, l, 15);
|
|
F3(l, r, 14);
|
|
F2(r, l, 13);
|
|
F1(l, r, 12);
|
|
}
|
|
F3(r, l, 11);
|
|
F2(l, r, 10);
|
|
F1(r, l, 9);
|
|
F3(l, r, 8);
|
|
F2(r, l, 7);
|
|
F1(l, r, 6);
|
|
F3(r, l, 5);
|
|
F2(l, r, 4);
|
|
F1(r, l, 3);
|
|
F3(l, r, 2);
|
|
F2(r, l, 1);
|
|
F1(l, r, 0);
|
|
/* Put l,r into outblock */
|
|
block[0] = U8a(l);
|
|
block[1] = U8b(l);
|
|
block[2] = U8c(l);
|
|
block[3] = U8d(l);
|
|
block[4] = U8a(r);
|
|
block[5] = U8b(r);
|
|
block[6] = U8c(r);
|
|
block[7] = U8d(r);
|
|
/* Wipe clean */
|
|
t = l = r = 0;
|
|
}
|
|
|
|
|
|
/***** Key Schedual *****/
|
|
|
|
WIN32DLL_DEFINE
|
|
int _mcrypt_set_key(CAST_KEY * key, u8 * rawkey, unsigned keybytes)
|
|
{
|
|
u32 t[4], z[4], x[4];
|
|
unsigned i;
|
|
|
|
/* Set number of rounds to 12 or 16, depending on key length */
|
|
key->rounds = (keybytes <= CAST_SMALL_KEY)
|
|
? CAST_SMALL_ROUNDS : CAST_FULL_ROUNDS;
|
|
|
|
|
|
/* Copy key to workspace x */
|
|
for (i = 0; i < 4; i++) {
|
|
x[i] = 0;
|
|
if ((i * 4 + 0) < keybytes)
|
|
x[i] = (u32) rawkey[i * 4 + 0] << 24;
|
|
if ((i * 4 + 1) < keybytes)
|
|
x[i] |= (u32) rawkey[i * 4 + 1] << 16;
|
|
if ((i * 4 + 2) < keybytes)
|
|
x[i] |= (u32) rawkey[i * 4 + 2] << 8;
|
|
if ((i * 4 + 3) < keybytes)
|
|
x[i] |= (u32) rawkey[i * 4 + 3];
|
|
}
|
|
/* Generate 32 subkeys, four at a time */
|
|
for (i = 0; i < 32; i += 4) {
|
|
switch (i & 4) {
|
|
case 0:
|
|
t[0] = z[0] = x[0] ^ cast_sbox5[U8b(x[3])]
|
|
^ cast_sbox6[U8d(x[3])] ^ cast_sbox7[U8a(x[3])]
|
|
^ cast_sbox8[U8c(x[3])] ^
|
|
cast_sbox7[U8a(x[2])];
|
|
t[1] = z[1] = x[2] ^ cast_sbox5[U8a(z[0])]
|
|
^ cast_sbox6[U8c(z[0])] ^ cast_sbox7[U8b(z[0])]
|
|
^ cast_sbox8[U8d(z[0])] ^
|
|
cast_sbox8[U8c(x[2])];
|
|
t[2] = z[2] = x[3] ^ cast_sbox5[U8d(z[1])]
|
|
^ cast_sbox6[U8c(z[1])] ^ cast_sbox7[U8b(z[1])]
|
|
^ cast_sbox8[U8a(z[1])] ^
|
|
cast_sbox5[U8b(x[2])];
|
|
t[3] = z[3] =
|
|
x[1] ^ cast_sbox5[U8c(z[2])] ^
|
|
cast_sbox6[U8b(z[2])] ^ cast_sbox7[U8d(z[2])]
|
|
^ cast_sbox8[U8a(z[2])] ^
|
|
cast_sbox6[U8d(x[2])];
|
|
break;
|
|
case 4:
|
|
t[0] = x[0] = z[2] ^ cast_sbox5[U8b(z[1])]
|
|
^ cast_sbox6[U8d(z[1])] ^ cast_sbox7[U8a(z[1])]
|
|
^ cast_sbox8[U8c(z[1])] ^
|
|
cast_sbox7[U8a(z[0])];
|
|
t[1] = x[1] = z[0] ^ cast_sbox5[U8a(x[0])]
|
|
^ cast_sbox6[U8c(x[0])] ^ cast_sbox7[U8b(x[0])]
|
|
^ cast_sbox8[U8d(x[0])] ^
|
|
cast_sbox8[U8c(z[0])];
|
|
t[2] = x[2] = z[1] ^ cast_sbox5[U8d(x[1])]
|
|
^ cast_sbox6[U8c(x[1])] ^ cast_sbox7[U8b(x[1])]
|
|
^ cast_sbox8[U8a(x[1])] ^
|
|
cast_sbox5[U8b(z[0])];
|
|
t[3] = x[3] = z[3] ^ cast_sbox5[U8c(x[2])]
|
|
^ cast_sbox6[U8b(x[2])] ^ cast_sbox7[U8d(x[2])]
|
|
^ cast_sbox8[U8a(x[2])] ^
|
|
cast_sbox6[U8d(z[0])];
|
|
break;
|
|
}
|
|
switch (i & 12) {
|
|
case 0:
|
|
case 12:
|
|
key->xkey[i + 0] =
|
|
cast_sbox5[U8a(t[2])] ^ cast_sbox6[U8b(t[2])]
|
|
^ cast_sbox7[U8d(t[1])] ^
|
|
cast_sbox8[U8c(t[1])];
|
|
key->xkey[i + 1] =
|
|
cast_sbox5[U8c(t[2])] ^ cast_sbox6[U8d(t[2])]
|
|
^ cast_sbox7[U8b(t[1])] ^
|
|
cast_sbox8[U8a(t[1])];
|
|
key->xkey[i + 2] =
|
|
cast_sbox5[U8a(t[3])] ^ cast_sbox6[U8b(t[3])]
|
|
^ cast_sbox7[U8d(t[0])] ^
|
|
cast_sbox8[U8c(t[0])];
|
|
key->xkey[i + 3] =
|
|
cast_sbox5[U8c(t[3])] ^ cast_sbox6[U8d(t[3])]
|
|
^ cast_sbox7[U8b(t[0])] ^
|
|
cast_sbox8[U8a(t[0])];
|
|
break;
|
|
case 4:
|
|
case 8:
|
|
key->xkey[i + 0] =
|
|
cast_sbox5[U8d(t[0])] ^ cast_sbox6[U8c(t[0])]
|
|
^ cast_sbox7[U8a(t[3])] ^
|
|
cast_sbox8[U8b(t[3])];
|
|
key->xkey[i + 1] =
|
|
cast_sbox5[U8b(t[0])] ^ cast_sbox6[U8a(t[0])]
|
|
^ cast_sbox7[U8c(t[3])] ^
|
|
cast_sbox8[U8d(t[3])];
|
|
key->xkey[i + 2] =
|
|
cast_sbox5[U8d(t[1])] ^ cast_sbox6[U8c(t[1])]
|
|
^ cast_sbox7[U8a(t[2])] ^
|
|
cast_sbox8[U8b(t[2])];
|
|
key->xkey[i + 3] =
|
|
cast_sbox5[U8b(t[1])] ^ cast_sbox6[U8a(t[1])]
|
|
^ cast_sbox7[U8c(t[2])] ^
|
|
cast_sbox8[U8d(t[2])];
|
|
break;
|
|
}
|
|
switch (i & 12) {
|
|
case 0:
|
|
key->xkey[i + 0] ^= cast_sbox5[U8c(z[0])];
|
|
key->xkey[i + 1] ^= cast_sbox6[U8c(z[1])];
|
|
key->xkey[i + 2] ^= cast_sbox7[U8b(z[2])];
|
|
key->xkey[i + 3] ^= cast_sbox8[U8a(z[3])];
|
|
break;
|
|
case 4:
|
|
key->xkey[i + 0] ^= cast_sbox5[U8a(x[2])];
|
|
key->xkey[i + 1] ^= cast_sbox6[U8b(x[3])];
|
|
key->xkey[i + 2] ^= cast_sbox7[U8d(x[0])];
|
|
key->xkey[i + 3] ^= cast_sbox8[U8d(x[1])];
|
|
break;
|
|
case 8:
|
|
key->xkey[i + 0] ^= cast_sbox5[U8b(z[2])];
|
|
key->xkey[i + 1] ^= cast_sbox6[U8a(z[3])];
|
|
key->xkey[i + 2] ^= cast_sbox7[U8c(z[0])];
|
|
key->xkey[i + 3] ^= cast_sbox8[U8c(z[1])];
|
|
break;
|
|
case 12:
|
|
key->xkey[i + 0] ^= cast_sbox5[U8d(x[0])];
|
|
key->xkey[i + 1] ^= cast_sbox6[U8d(x[1])];
|
|
key->xkey[i + 2] ^= cast_sbox7[U8a(x[2])];
|
|
key->xkey[i + 3] ^= cast_sbox8[U8b(x[3])];
|
|
break;
|
|
}
|
|
if (i >= 16) {
|
|
key->xkey[i + 0] &= 31;
|
|
key->xkey[i + 1] &= 31;
|
|
key->xkey[i + 2] &= 31;
|
|
key->xkey[i + 3] &= 31;
|
|
}
|
|
}
|
|
/* Wipe clean */
|
|
for (i = 0; i < 4; i++) {
|
|
t[i] = x[i] = z[i] = 0;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Made in Canada */
|
|
|
|
|
|
WIN32DLL_DEFINE int _mcrypt_get_size()
|
|
{
|
|
return sizeof(CAST_KEY);
|
|
}
|
|
WIN32DLL_DEFINE int _mcrypt_get_block_size()
|
|
{
|
|
return 8;
|
|
}
|
|
WIN32DLL_DEFINE int _is_block_algorithm()
|
|
{
|
|
return 1;
|
|
}
|
|
WIN32DLL_DEFINE int _mcrypt_get_key_size()
|
|
{
|
|
return 16;
|
|
}
|
|
|
|
static const int key_sizes[] = { 16 };
|
|
WIN32DLL_DEFINE const int *_mcrypt_get_supported_key_sizes(int *len)
|
|
{
|
|
*len = sizeof(key_sizes)/sizeof(int);
|
|
return key_sizes;
|
|
|
|
}
|
|
|
|
WIN32DLL_DEFINE const char *_mcrypt_get_algorithms_name()
|
|
{
|
|
return "CAST-128";
|
|
}
|
|
|
|
#define CIPHER "434e25460c8c9525"
|
|
|
|
WIN32DLL_DEFINE int _mcrypt_self_test()
|
|
{
|
|
char *keyword;
|
|
unsigned char plaintext[16];
|
|
unsigned char ciphertext[16];
|
|
int blocksize = _mcrypt_get_block_size(), j;
|
|
void *key;
|
|
unsigned char cipher_tmp[200];
|
|
|
|
keyword = calloc(1, _mcrypt_get_key_size());
|
|
if (keyword == NULL)
|
|
return -1;
|
|
|
|
for (j = 0; j < _mcrypt_get_key_size(); j++) {
|
|
keyword[j] = ((j * 2 + 10) % 256);
|
|
}
|
|
|
|
for (j = 0; j < blocksize; j++) {
|
|
plaintext[j] = j % 256;
|
|
}
|
|
key = malloc(_mcrypt_get_size());
|
|
if (key == NULL)
|
|
return -1;
|
|
|
|
memcpy(ciphertext, plaintext, blocksize);
|
|
|
|
_mcrypt_set_key(key, (void *) keyword, _mcrypt_get_key_size());
|
|
free(keyword);
|
|
_mcrypt_encrypt(key, (void *) ciphertext);
|
|
|
|
for (j = 0; j < blocksize; j++) {
|
|
sprintf(&((char *) cipher_tmp)[2 * j], "%.2x",
|
|
ciphertext[j]);
|
|
}
|
|
|
|
if (strcmp((char *) cipher_tmp, CIPHER) != 0) {
|
|
printf("failed compatibility\n");
|
|
printf("Expected: %s\nGot: %s\n", CIPHER,
|
|
(char *) cipher_tmp);
|
|
free(key);
|
|
return -1;
|
|
}
|
|
_mcrypt_decrypt(key, (void *) ciphertext);
|
|
free(key);
|
|
|
|
if (strcmp(ciphertext, plaintext) != 0) {
|
|
printf("failed internally\n");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
WIN32DLL_DEFINE word32 _mcrypt_algorithm_version()
|
|
{
|
|
return 20010801;
|
|
}
|
|
|
|
#ifdef WIN32
|
|
# ifdef USE_LTDL
|
|
WIN32DLL_DEFINE int main (void)
|
|
{
|
|
/* empty main function to avoid linker error (see cygwin FAQ) */
|
|
}
|
|
# endif
|
|
#endif
|