/**
Initialize the AES (Rijndael) block cipher
@param key The symmetric key you wish to pass
@param keylen The key length in bytes
@param num_rounds The number of rounds desired (0 for default)
@param skey The key in as scheduled by this function.
@return CRYPT_OK if successful
*/
int SETUP(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
{
int i, j;
ulong32 temp, *rk;
#ifndef ENCRYPT_ONLY
ulong32 *rrk;
#endif
LTC_ARGCHK(key != NULL);
LTC_ARGCHK(skey != NULL);
if (keylen != 16 && keylen != 24 && keylen != 32) {
return CRYPT_INVALID_KEYSIZE;
}
if (num_rounds != 0 && num_rounds != (10 + ((keylen/8)-2)*2)) {
return CRYPT_INVALID_ROUNDS;
}
skey->rijndael.Nr = 10 + ((keylen/8)-2)*2;
/* setup the forward key */
i = 0;
rk = skey->rijndael.eK;
LOAD32H(rk[0], key );
LOAD32H(rk[1], key + 4);
LOAD32H(rk[2], key + 8);
LOAD32H(rk[3], key + 12);
if (keylen == 16) {
j = 44;
for (;;) {
temp = rk[3];
rk[4] = rk[0] ^ setup_mix(temp) ^ rcon[i];
rk[5] = rk[1] ^ rk[4];
rk[6] = rk[2] ^ rk[5];
rk[7] = rk[3] ^ rk[6];
if (++i == 10) {
break;
}
rk += 4;
}
} else if (keylen == 24) {
j = 52;
LOAD32H(rk[4], key + 16);
LOAD32H(rk[5], key + 20);
for (;;) {
#ifdef _MSC_VER
temp = skey->rijndael.eK[rk - skey->rijndael.eK + 5];
#else
temp = rk[5];
#endif
rk[ 6] = rk[ 0] ^ setup_mix(temp) ^ rcon[i];
rk[ 7] = rk[ 1] ^ rk[ 6];
rk[ 8] = rk[ 2] ^ rk[ 7];
rk[ 9] = rk[ 3] ^ rk[ 8];
if (++i == 8) {
break;
}
rk[10] = rk[ 4] ^ rk[ 9];
rk[11] = rk[ 5] ^ rk[10];
rk += 6;
}
} else if (keylen == 32) {
j = 60;
LOAD32H(rk[4], key + 16);
LOAD32H(rk[5], key + 20);
LOAD32H(rk[6], key + 24);
LOAD32H(rk[7], key + 28);
for (;;) {
#ifdef _MSC_VER
temp = skey->rijndael.eK[rk - skey->rijndael.eK + 7];
#else
temp = rk[7];
#endif
rk[ 8] = rk[ 0] ^ setup_mix(temp) ^ rcon[i];
rk[ 9] = rk[ 1] ^ rk[ 8];
rk[10] = rk[ 2] ^ rk[ 9];
rk[11] = rk[ 3] ^ rk[10];
if (++i == 7) {
break;
}
temp = rk[11];
rk[12] = rk[ 4] ^ setup_mix(RORc(temp, 8));
rk[13] = rk[ 5] ^ rk[12];
rk[14] = rk[ 6] ^ rk[13];
rk[15] = rk[ 7] ^ rk[14];
rk += 8;
}
} else {
/* this can't happen */
return CRYPT_ERROR;
}
#ifndef ENCRYPT_ONLY
/* setup the inverse key now */
rk = skey->rijndael.dK;
rrk = skey->rijndael.eK + j - 4;
/* apply the inverse MixColumn transform to all round keys but the first and the last: */
/* copy first */
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk = *rrk;
rk -= 3; rrk -= 3;
for (i = 1; i < skey->rijndael.Nr; i++) {
rrk -= 4;
rk += 4;
#ifdef LTC_SMALL_CODE
temp = rrk[0];
rk[0] = setup_mix2(temp);
temp = rrk[1];
rk[1] = setup_mix2(temp);
temp = rrk[2];
rk[2] = setup_mix2(temp);
temp = rrk[3];
rk[3] = setup_mix2(temp);
#else
temp = rrk[0];
rk[0] =
Tks0[byte(temp, 3)] ^
Tks1[byte(temp, 2)] ^
Tks2[byte(temp, 1)] ^
Tks3[byte(temp, 0)];
temp = rrk[1];
rk[1] =
Tks0[byte(temp, 3)] ^
Tks1[byte(temp, 2)] ^
Tks2[byte(temp, 1)] ^
Tks3[byte(temp, 0)];
temp = rrk[2];
rk[2] =
Tks0[byte(temp, 3)] ^
Tks1[byte(temp, 2)] ^
Tks2[byte(temp, 1)] ^
Tks3[byte(temp, 0)];
temp = rrk[3];
rk[3] =
Tks0[byte(temp, 3)] ^
Tks1[byte(temp, 2)] ^
Tks2[byte(temp, 1)] ^
Tks3[byte(temp, 0)];
#endif
}
/* copy last */
rrk -= 4;
rk += 4;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk = *rrk;
#endif /* ENCRYPT_ONLY */
return CRYPT_OK;
}
/*!
Initialize the AES (Rijndael) block cipher
@param key The symmetric key you wish to pass
@param keylen The key length in bytes
@param num_rounds The number of rounds desired (0 for default)
@param skey The key in as scheduled by this function.
@return CRYPT_OK if successful
*/
static int ccaes_ltc_init(const unsigned char *key, int keylen, int num_rounds,
ccecb_ctx *skey)
{
int i, j;
uint32_t temp, *rk;
#ifndef ENCRYPT_ONLY
uint32_t *rrk;
#endif
ltc_rijndael_keysched *rijndael;
rijndael = (ltc_rijndael_keysched *)skey;
if (keylen != 16 && keylen != 24 && keylen != 32) {
return -1; //CRYPT_INVALID_KEYSIZE;
}
if (num_rounds != 0 && num_rounds != (10 + ((keylen/8)-2)*2)) {
return -1; //CRYPT_INVALID_ROUNDS;
}
rijndael->Nr = 10 + ((keylen/8)-2)*2;
/* setup the forward key */
i = 0;
rk = rijndael->eK;
CC_LOAD32_BE(rk[0], key );
CC_LOAD32_BE(rk[1], key + 4);
CC_LOAD32_BE(rk[2], key + 8);
CC_LOAD32_BE(rk[3], key + 12);
if (keylen == 16) {
j = 44;
for (;;) {
temp = rk[3];
rk[4] = rk[0] ^ setup_mix(temp) ^ rcon[i];
rk[5] = rk[1] ^ rk[4];
rk[6] = rk[2] ^ rk[5];
rk[7] = rk[3] ^ rk[6];
if (++i == 10) {
break;
}
rk += 4;
}
} else if (keylen == 24) {
j = 52;
CC_LOAD32_BE(rk[4], key + 16);
CC_LOAD32_BE(rk[5], key + 20);
for (;;) {
#ifdef _MSC_VER
temp = rijndael->eK[rk - rijndael->eK + 5];
#else
temp = rk[5];
#endif
rk[ 6] = rk[ 0] ^ setup_mix(temp) ^ rcon[i];
rk[ 7] = rk[ 1] ^ rk[ 6];
rk[ 8] = rk[ 2] ^ rk[ 7];
rk[ 9] = rk[ 3] ^ rk[ 8];
if (++i == 8) {
break;
}
rk[10] = rk[ 4] ^ rk[ 9];
rk[11] = rk[ 5] ^ rk[10];
rk += 6;
}
} else if (keylen == 32) {
j = 60;
CC_LOAD32_BE(rk[4], key + 16);
CC_LOAD32_BE(rk[5], key + 20);
CC_LOAD32_BE(rk[6], key + 24);
CC_LOAD32_BE(rk[7], key + 28);
for (;;) {
#ifdef _MSC_VER
temp = rijndael->eK[rk - rijndael->eK + 7];
#else
temp = rk[7];
#endif
rk[ 8] = rk[ 0] ^ setup_mix(temp) ^ rcon[i];
rk[ 9] = rk[ 1] ^ rk[ 8];
rk[10] = rk[ 2] ^ rk[ 9];
rk[11] = rk[ 3] ^ rk[10];
if (++i == 7) {
break;
}
temp = rk[11];
rk[12] = rk[ 4] ^ setup_mix(CC_RORc(temp, 8));
rk[13] = rk[ 5] ^ rk[12];
rk[14] = rk[ 6] ^ rk[13];
rk[15] = rk[ 7] ^ rk[14];
rk += 8;
}
} else {
/* this can't happen */
return -1; //CRYPT_ERROR;
}
#ifndef ENCRYPT_ONLY
/* setup the inverse key now */
rk = rijndael->dK;
rrk = rijndael->eK + j - 4;
/* apply the inverse MixColumn transform to all round keys but the first and the last: */
/* copy first */
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk = *rrk;
rk -= 3; rrk -= 3;
for (i = 1; i < rijndael->Nr; i++) {
rrk -= 4;
rk += 4;
#ifdef LTC_SMALL_CODE
temp = rrk[0];
rk[0] = setup_mix2(temp);
temp = rrk[1];
rk[1] = setup_mix2(temp);
temp = rrk[2];
rk[2] = setup_mix2(temp);
temp = rrk[3];
rk[3] = setup_mix2(temp);
#else
temp = rrk[0];
rk[0] =
Tks0[cc_byte(temp, 3)] ^
Tks1[cc_byte(temp, 2)] ^
Tks2[cc_byte(temp, 1)] ^
Tks3[cc_byte(temp, 0)];
temp = rrk[1];
rk[1] =
Tks0[cc_byte(temp, 3)] ^
Tks1[cc_byte(temp, 2)] ^
Tks2[cc_byte(temp, 1)] ^
Tks3[cc_byte(temp, 0)];
temp = rrk[2];
rk[2] =
Tks0[cc_byte(temp, 3)] ^
Tks1[cc_byte(temp, 2)] ^
Tks2[cc_byte(temp, 1)] ^
Tks3[cc_byte(temp, 0)];
temp = rrk[3];
rk[3] =
Tks0[cc_byte(temp, 3)] ^
Tks1[cc_byte(temp, 2)] ^
Tks2[cc_byte(temp, 1)] ^
Tks3[cc_byte(temp, 0)];
#endif
}
/* copy last */
rrk -= 4;
rk += 4;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk++ = *rrk++;
*rk = *rrk;
#endif /* ENCRYPT_ONLY */
return 0; //CRYPT_OK;
}
