SizeT AesCbc_Decode(CAesCbc *p, Byte *data, SizeT size)
{
if (size == 0)
return 0;
if (size < AES_BLOCK_SIZE)
return AES_BLOCK_SIZE;
size -= AES_BLOCK_SIZE;
SizeT i;
UInt32 in[4], out[4];
for (i = 0; i <= size; i += AES_BLOCK_SIZE, data += AES_BLOCK_SIZE)
{
in[0] = GetUi32(data);
in[1] = GetUi32(data + 4);
in[2] = GetUi32(data + 8);
in[3] = GetUi32(data + 12);
AesDecode32(out, in, p->aes.rkey, p->aes.numRounds2);
SetUi32(data, p->prev[0] ^ out[0]);
SetUi32(data + 4, p->prev[1] ^ out[1]);
SetUi32(data + 8, p->prev[2] ^ out[2]);
SetUi32(data + 12, p->prev[3] ^ out[3]);
p->prev[0] = in[0];
p->prev[1] = in[1];
p->prev[2] = in[2];
p->prev[3] = in[3];
}
return i;
}
UInt32 MY_FAST_CALL AesCbcDecode(CAesCbc *cbc, Byte *data, UInt32 size)
{
UInt32 i;
UInt32 in[4], out[4];
if (size == 0)
return 0;
if (size < AES_BLOCK_SIZE)
return AES_BLOCK_SIZE;
size -= AES_BLOCK_SIZE;
for (i = 0; i <= size; i += AES_BLOCK_SIZE, data += AES_BLOCK_SIZE)
{
in[0] = GetUi32(data);
in[1] = GetUi32(data + 4);
in[2] = GetUi32(data + 8);
in[3] = GetUi32(data + 12);
AesDecode32(in, out, cbc->aes.rkey, cbc->aes.numRounds2);
SetUi32(data, cbc->prev[0] ^ out[0]);
SetUi32(data + 4, cbc->prev[1] ^ out[1]);
SetUi32(data + 8, cbc->prev[2] ^ out[2]);
SetUi32(data + 12, cbc->prev[3] ^ out[3]);
cbc->prev[0] = in[0];
cbc->prev[1] = in[1];
cbc->prev[2] = in[2];
cbc->prev[3] = in[3];
}
return i;
}
void Aes_Decode32(const CAes *p, UInt32 *dest, const UInt32 *src)
{
AesDecode32(dest, src, p->rkey, p->numRounds2);
}
