def test_mult_gf2(self):
# Prove mult by zero
x = _mult_gf2(0, 0)
self.assertEqual(x, 0)
# Prove mult by unity
x = _mult_gf2(34, 1)
self.assertEqual(x, 34)
z = 3 # (x+1)
y = _mult_gf2(z, z)
self.assertEqual(y, 5) # (x+1)^2 = x^2 + 1
y = _mult_gf2(y, z)
self.assertEqual(y, 15) # (x+1)^3 = x^3 + x^2 + x + 1
y = _mult_gf2(y, z)
self.assertEqual(y, 17) # (x+1)^4 = x^4 + 1
# Prove linearity works
comps = [1, 4, 128, 2**34]
sum_comps = 1 + 4 + 128 + 2**34
y = 908
z = _mult_gf2(sum_comps, y)
w = 0
for x in comps:
w ^= _mult_gf2(x, y)
self.assertEqual(w, z)
def test_mult_gf2(self):
# Prove mult by zero
x = _mult_gf2(0,0)
self.assertEqual(x, 0)
# Prove mult by unity
x = _mult_gf2(34, 1)
self.assertEqual(x, 34)
z = 3 # (x+1)
y = _mult_gf2(z, z)
self.assertEqual(y, 5) # (x+1)^2 = x^2 + 1
y = _mult_gf2(y, z)
self.assertEqual(y, 15) # (x+1)^3 = x^3 + x^2 + x + 1
y = _mult_gf2(y, z)
self.assertEqual(y, 17) # (x+1)^4 = x^4 + 1
# Prove linearity works
comps = [1, 4, 128, 2L**34]
sum_comps = 1+4+128+2L**34
y = 908
z = _mult_gf2(sum_comps, y)
w = 0
for x in comps:
w ^= _mult_gf2(x, y)
self.assertEqual(w, z)
def test_div_gf2(self):
from Crypto.Util.number import size as deg
x, y = _div_gf2(567, 7)
self.failUnless(deg(y) < deg(7))
w = _mult_gf2(x, 7) ^ y
self.assertEqual(567, w)
x, y = _div_gf2(7, 567)
self.assertEqual(x, 0)
self.assertEqual(y, 7)
def test_div_gf2(self):
from Crypto.Util.number import size as deg
x, y = _div_gf2(567, 7)
self.failUnless(deg(y) < deg(7))
w = _mult_gf2(x, 7) ^ y
self.assertEqual(567, w)
x, y = _div_gf2(7, 567)
self.assertEqual(x, 0)
self.assertEqual(y, 7)