void speck32_encrypt(const void *keys, int enc, void *data)
{
uint16_t i, x0, x1;
uint16_t *ks=(uint16_t*)keys;
uint16_t *x=(uint16_t*)data;
// copy input to local space
x0 = x[0]; x1 = x[1];
for (i=0; i<22; i++)
{
if (enc == SPECK_DECRYPT)
{
x1 = ROTR16(x1 ^ x0, 2);
x0 ^= ks[22-1-i];
x0 -= x1;
x0 = ROTL16(x0, 7);
} else {
x0 = (ROTR16(x0, 7) + x1) ^ ks[i];
x1 = ROTL16(x1, 2) ^ x0;
}
}
// save result
x[0] = x0; x[1] = x1;
}
void speck32_encryptx(const void *key, void *data)
{
uint16_t i, t, k0, k1, k2, k3, x0, x1;
uint16_t *k=(uint16_t*)key;
uint16_t *x=(uint16_t*)data;
// copy 128-bit key to local space
k0 = k[0]; k1 = k[1];
k2 = k[2]; k3 = k[3];
// copy input to local space
x0 = x[0]; x1 = x[1];
for (i=0; i<22; i++)
{
// encrypt block
x0 = (ROTR16(x0, 7) + x1) ^ k0;
x1 = ROTL16(x1, 2) ^ x0;
// create next subkey
k1 = (ROTR16(k1, 7) + k0) ^ i;
k0 = ROTL16(k0, 2) ^ k1;
XCHG(k3, k2);
XCHG(k3, k1);
}
// save result
x[0] = x0; x[1] = x1;
}
void speck32_setkey(const void *in, void *out)
{
uint16_t i, t, k0, k1, k2, k3;
uint16_t *k=(uint16_t*)in;
uint16_t *ks=(uint16_t*)out;
// copy 64-bit key to local space
k0 = k[0]; k1 = k[1];
k2 = k[2]; k3 = k[3];
// expand 64-bit key into round keys
for (i=0; i<22; i++)
{
ks[i] = k0;
k1 = (ROTR16(k1, 7) + k0) ^ i;
k0 = ROTL16(k0, 2) ^ k1;
// rotate left 32-bits
XCHG(k3, k2);
XCHG(k3, k1);
}
}
void InvShiftRows(WORD in[Nb])
{
ROTL8(in[1]);
ROTL16(in[2]);
ROTL24(in[3]);
}
