void intel_AES_dec192_CBC(UCHAR *cipherText,UCHAR *plainText,UCHAR *key,size_t numBlocks,UCHAR *iv)
{
DEFINE_ROUND_KEYS
sAesData aesData;
aesData.in_block = cipherText;
aesData.out_block = plainText;
aesData.expanded_key = expandedKey;
aesData.num_blocks = numBlocks;
aesData.iv = iv;
iDecExpandKey192(key,expandedKey);
iDec192_CBC(&aesData);
}
void tDecAES::dec(u8* ctbuf, u8* ptbuf, u32 numblocks, u8* iv)
{
// Fast ASM impl:
if (m_useASM)
{
sAesData data;
data.in_block = ctbuf;
data.out_block = ptbuf;
data.expanded_key = m_expandedKey;
data.iv = iv;
data.num_blocks = numblocks;
if (m_opmode == kOpModeCBC && iv)
{
switch (m_keylen)
{
case k128bit: iDec128_CBC(&data); break;
case k192bit: iDec192_CBC(&data); break;
case k256bit: iDec256_CBC(&data); break;
default: throw eInvalidArgument("The keylen parameter is not valid!");
}
}
else
{
switch (m_keylen)
{
case k128bit: iDec128(&data); break;
case k192bit: iDec192(&data); break;
case k256bit: iDec256(&data); break;
default: throw eInvalidArgument("The keylen parameter is not valid!");
}
}
}
// Fallback impl:
else
{
u32* rk = m_rk;
int Nr = m_Nr;
if (m_opmode == kOpModeCBC && iv)
{
u8 ct[AES_BLOCK_SIZE];
for (u32 i = 0; numblocks > 0; i+=AES_BLOCK_SIZE, --numblocks)
{
for (u32 j = 0; j < AES_BLOCK_SIZE; j++)
ct[j] = ctbuf[i+j];
rijndaelDecrypt(rk, Nr, ct, ptbuf+i);
for (u32 j = 0; j < AES_BLOCK_SIZE; j++)
{
ptbuf[i+j] ^= iv[j];
iv[j] = ct[j];
}
}
}
else
{
for (u32 i = 0; numblocks > 0; i+=AES_BLOCK_SIZE, --numblocks)
{
rijndaelDecrypt(rk, Nr, ctbuf+i, ptbuf+i);
}
}
}
}
