Function mont_mul

modules/crypt/arith/xsBigIntEx.c:462–489

}

static txBigInt *mont_mul(txMachine *the, txBigInt *r, txBigInt *a, txBigInt *b, txBigInt *m, txU4 u, pool_t *pool)
{
	int i, n, sz;
	txBigInt *t1, *t2, *t3;

	sz = MAX(b->size + 1, m->size + 1) + 1;
	t1 = pool_get(the, sz, pool);
	t2 = pool_get(the, sz, pool);
	t3 = pool_get(the, sz + 1, pool);
	t3->size = 1;
	t3->data[0] = 0;
	for (i = 0, n = m->size; i < n; i++) {
		txU4 s = i < a->size ? a->data[i] : 0;
		txU4 u1 = (t3->data[0] + s * b->data[0]) * u;
		fxBigInt_umul1(the, t1, b, s);
		fxBigInt_umul1(the, t2, m, u1);
		fxBigInt_uadd(the, t1, t1, t2);
		fxBigInt_uadd(the, t3, t3, t1);
		fxBigInt_ulsr1(the, t3, t3, mxBigIntWordSize);
	}
	if (fxBigInt_ucomp(t3, m) >= 0)
		fxBigInt_sub(the, t3, t3, m);
	fxBigInt_copy(r, t3);
	pool_put(t3, sz + 1);
	pool_put(t2, sz);
	pool_put(t1, sz);
	return r;
}

static txBigInt *mont_square(txMachine *the, txBigInt *r, txBigInt *a, txBigInt *m, txU4 u, pool_t *pool)
{