/* $OpenXM: OpenXM/src/ox_ntl/crypt/cast5/cast5.c,v 1.1 2004/07/15 14:51:42 iwane Exp $ */
/*
* rfc 2144
* The CAST-128 Encryption Algorithm
*/
#include <unistd.h>
#include "cast5.h"
#include "cast5tbl.h"
#if HAVE_CONFIG_H
#include "config.h"
#endif /* HAVE_CONFIG_H */
#define leftrot32(x, n) ((((uint32_t)x) << n) | ((uint32_t)x) >> (32 - n))
#ifdef WORDS_BIGENDIAN
#define ARY(x, i) (((unsigned char *)(x))[i])
#else
#define ARY(x, i) (((unsigned char *)(x))[(int)("\x03\x02\x01\x00\x07\x06\x05\x04\x0b\x0a\x09\x08\x0f\x0e\x0d\x0c"[i])])
#endif
/*
#define ARY(x, i) (((unsigned char *)(x))[((((i) / 4) * 4) + (3 - (i) % 4))])
* compute: 7.473
* 15.100
* 11.805
*
#define ARY(x, i) (((unsigned char *)(x))[(int)("\x03\x02\x01\x00\x07\x06\x05\x04\x0b\x0a\x09\x08\x0f\x0e\x0d\x0c"[i])])
* char array: 7.044
* 14.124
* 11.366
*
static const int _ar[] = {3, 2, 1, 0, 7, 6, 5, 4, 11, 10, 9, 8, 15, 14, 13, 12};
#define ARY(x, i) (((unsigned char *)(x))[_ar[i]])
* int array: 8.679
* 17.233
* 12.705
*/
/*
* length of key is 16 byte = 128 bit.
*/
void
cast128_keyset(const unsigned char *key, int len, cast128_key *ckey)
{
#define X(i) (ARY(&x, i))
#define Z(i) (ARY(&z, i))
uint32_t x[4], z[4];
int i;
uint32_t K[32], *k;
if (len > 16)
len = 16;
for (i = 0; i < len; i++) {
X(i) = key[i];
}
for (; i < (int)sizeof(x); i++) {
X(i) = 0;
}
k = K;
for (i = 0; i < 2; i++) {
#define s5 __cast128_tbl_s5
#define s6 __cast128_tbl_s6
#define s7 __cast128_tbl_s7
#define s8 __cast128_tbl_s8
z[0] = x[0] ^ s5[X(0xD)] ^ s6[X(0xF)] ^ s7[X(0xC)] ^ s8[X(0xE)] ^ s7[X(0x8)];
z[1] = x[2] ^ s5[Z(0x0)] ^ s6[Z(0x2)] ^ s7[Z(0x1)] ^ s8[Z(0x3)] ^ s8[X(0xA)];
z[2] = x[3] ^ s5[Z(0x7)] ^ s6[Z(0x6)] ^ s7[Z(0x5)] ^ s8[Z(0x4)] ^ s5[X(0x9)];
z[3] = x[1] ^ s5[Z(0xA)] ^ s6[Z(0x9)] ^ s7[Z(0xB)] ^ s8[Z(0x8)] ^ s6[X(0xB)];
k[ 0] = s5[Z(0x8)] ^ s6[Z(0x9)] ^ s7[Z(0x7)] ^ s8[Z(0x6)] ^ s5[Z(0x2)];
k[ 1] = s5[Z(0xA)] ^ s6[Z(0xB)] ^ s7[Z(0x5)] ^ s8[Z(0x4)] ^ s6[Z(0x6)];
k[ 2] = s5[Z(0xC)] ^ s6[Z(0xD)] ^ s7[Z(0x3)] ^ s8[Z(0x2)] ^ s7[Z(0x9)];
k[ 3] = s5[Z(0xE)] ^ s6[Z(0xF)] ^ s7[Z(0x1)] ^ s8[Z(0x0)] ^ s8[Z(0xC)];
x[0] = z[2] ^ s5[Z(0x5)] ^ s6[Z(0x7)] ^ s7[Z(0x4)] ^ s8[Z(0x6)] ^ s7[Z(0x0)];
x[1] = z[0] ^ s5[X(0x0)] ^ s6[X(0x2)] ^ s7[X(0x1)] ^ s8[X(0x3)] ^ s8[Z(0x2)];
x[2] = z[1] ^ s5[X(0x7)] ^ s6[X(0x6)] ^ s7[X(0x5)] ^ s8[X(0x4)] ^ s5[Z(0x1)];
x[3] = z[3] ^ s5[X(0xA)] ^ s6[X(0x9)] ^ s7[X(0xB)] ^ s8[X(0x8)] ^ s6[Z(0x3)];
k[ 4] = s5[X(0x3)] ^ s6[X(0x2)] ^ s7[X(0xC)] ^ s8[X(0xD)] ^ s5[X(0x8)];
k[ 5] = s5[X(0x1)] ^ s6[X(0x0)] ^ s7[X(0xE)] ^ s8[X(0xF)] ^ s6[X(0xD)];
k[ 6] = s5[X(0x7)] ^ s6[X(0x6)] ^ s7[X(0x8)] ^ s8[X(0x9)] ^ s7[X(0x3)];
k[ 7] = s5[X(0x5)] ^ s6[X(0x4)] ^ s7[X(0xA)] ^ s8[X(0xB)] ^ s8[X(0x7)];
z[0] = x[0] ^ s5[X(0xD)] ^ s6[X(0xF)] ^ s7[X(0xC)] ^ s8[X(0xE)] ^ s7[X(0x8)];
z[1] = x[2] ^ s5[Z(0x0)] ^ s6[Z(0x2)] ^ s7[Z(0x1)] ^ s8[Z(0x3)] ^ s8[X(0xA)];
z[2] = x[3] ^ s5[Z(0x7)] ^ s6[Z(0x6)] ^ s7[Z(0x5)] ^ s8[Z(0x4)] ^ s5[X(0x9)];
z[3] = x[1] ^ s5[Z(0xA)] ^ s6[Z(0x9)] ^ s7[Z(0xB)] ^ s8[Z(0x8)] ^ s6[X(0xB)];
k[ 8] = s5[Z(0x3)] ^ s6[Z(0x2)] ^ s7[Z(0xC)] ^ s8[Z(0xD)] ^ s5[Z(0x9)];
k[ 9] = s5[Z(0x1)] ^ s6[Z(0x0)] ^ s7[Z(0xE)] ^ s8[Z(0xF)] ^ s6[Z(0xC)];
k[10] = s5[Z(0x7)] ^ s6[Z(0x6)] ^ s7[Z(0x8)] ^ s8[Z(0x9)] ^ s7[Z(0x2)];
k[11] = s5[Z(0x5)] ^ s6[Z(0x4)] ^ s7[Z(0xA)] ^ s8[Z(0xB)] ^ s8[Z(0x6)];
x[0] = z[2] ^ s5[Z(0x5)] ^ s6[Z(0x7)] ^ s7[Z(0x4)] ^ s8[Z(0x6)] ^ s7[Z(0x0)];
x[1] = z[0] ^ s5[X(0x0)] ^ s6[X(0x2)] ^ s7[X(0x1)] ^ s8[X(0x3)] ^ s8[Z(0x2)];
x[2] = z[1] ^ s5[X(0x7)] ^ s6[X(0x6)] ^ s7[X(0x5)] ^ s8[X(0x4)] ^ s5[Z(0x1)];
x[3] = z[3] ^ s5[X(0xA)] ^ s6[X(0x9)] ^ s7[X(0xB)] ^ s8[X(0x8)] ^ s6[Z(0x3)];
k[12] = s5[X(0x8)] ^ s6[X(0x9)] ^ s7[X(0x7)] ^ s8[X(0x6)] ^ s5[X(0x3)];
k[13] = s5[X(0xA)] ^ s6[X(0xB)] ^ s7[X(0x5)] ^ s8[X(0x4)] ^ s6[X(0x7)];
k[14] = s5[X(0xC)] ^ s6[X(0xD)] ^ s7[X(0x3)] ^ s8[X(0x2)] ^ s7[X(0x8)];
k[15] = s5[X(0xE)] ^ s6[X(0xF)] ^ s7[X(0x1)] ^ s8[X(0x0)] ^ s8[X(0xD)];
#undef s5
#undef s6
#undef s7
#undef s8
k += 16;
}
for (i = 0; i < 16; i++) {
ckey->km[i] = K[i];
ckey->kr[i] = K[i + 16] & 0x1f;
}
ckey->len = len;
if (len <= 10) /* < 80 bit */
ckey->loop = 12;
else
ckey->loop = 16;
#undef X
#undef Z
}
#define I(i) (ARY(&j, i))
#define _CAST_TYPE(FUNC, OP1, OP2, OP3) \
static inline uint32_t \
FUNC(uint32_t d, uint32_t km, uint32_t kr) \
{ \
uint32_t j = leftrot32(km OP3 d, kr); \
return (((__cast128_tbl_s1[I(0)] OP1 __cast128_tbl_s2[I(1)]) OP2 __cast128_tbl_s3[I(2)]) OP3 __cast128_tbl_s4[I(3)]); \
}
_CAST_TYPE(_type1, ^, -, +)
_CAST_TYPE(_type2, -, +, ^)
_CAST_TYPE(_type3, +, ^, -)
#undef I
void
cast128_enc_i(cast128_key *key,
uint32_t ml, uint32_t mr,
uint32_t *el, uint32_t *er)
{
int i;
uint32_t l;
uint32_t (*f[3])(uint32_t, uint32_t, uint32_t) = {_type1, _type2, _type3};
for (i = 0; i < key->loop; i++) {
l = mr;
mr = ml ^ f[i % 3](mr, key->km[i], key->kr[i]);
ml = l;
}
*er = ml;
*el = mr;
}
void
cast128_enc_c(cast128_key *key,
const unsigned char *msg, unsigned char *enc)
{
uint32_t m[2], e[2];
int i;
for (i = 0; i < 8; i++) {
ARY(m, i) = msg[i];
}
cast128_enc_i(key, m[0], m[1], &e[0], &e[1]);
for (i = 0; i < 8; i++) {
enc[i] = ARY(e, i);
}
}
void
cast128_dec_i(cast128_key *key,
uint32_t ml, uint32_t mr,
uint32_t *el, uint32_t *er)
{
int i;
uint32_t l;
uint32_t (*f[3])(uint32_t, uint32_t, uint32_t) = {_type1, _type2, _type3};
for (i = key->loop - 1; i >= 0; i--) {
l = mr;
mr = ml ^ f[i % 3](mr, key->km[i], key->kr[i]);
ml = l;
}
*er = ml;
*el = mr;
}
void
cast128_dec_c(cast128_key *key,
const unsigned char *msg, unsigned char *enc)
{
uint32_t m[2], e[2];
int i;
for (i = 0; i < 8; i++) {
ARY(m, i) = msg[i];
}
cast128_dec_i(key, m[0], m[1], &e[0], &e[1]);
for (i = 0; i < 8; i++) {
enc[i] = ARY(e, i);
}
}