def test_add_point__neg(self):
""" Negative test for ecgf2m_add_point(x1, y1, x2, y2, f, a=0b0) """
# Not meant to be called with other values than int or long
self.failUnlessRaises(ValueError, ar.ecgf2m_add_point, 0.0, 0b1111,0b111,0b111,0b10011)
self.failUnlessRaises(ValueError, ar.ecgf2m_add_point, 0b1000, "asdf" ,0b111,0b111,0b10011)
result = ar.ecgf2m_add_point(-0b111,0b111,0b1000,0b1111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(0b111,0b111,-0b1000,0b1111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(0b111,-0b111,0b1000,0b1111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(0b111,0b111,0b1000,-0b1111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(-0b111,-0b111,-0b1000,-0b1111,-0b10011)
self.assertEqual(result, (0b1100, 0b110))
def test_add_point__pos(self):
""" Positive test for ecgf2m_add_point(x1, y1, x2, y2, f, a=0b0)
Sage test calculations::
sage: F.<x> = GF(2)[]
sage: KK.<y> = GF(2**4, name='y', modulus=x^4 + x + 1 )
sage: E = EllipticCurve(KK, [1,0,0,0,1])
sage: p1 = E.point((y^3, y^3 + y^2 + y + 1, 1))
sage: p2 = E.point((y^2 + y + 1, y^2 + y + 1, 1))
sage: p1+p2
(y^3 + y^2 : y^2 + y : 1)
sage: p1*2
(y^2 + y : y^2 + y : 1)
sage: p1+p1
(y^2 + y : y^2 + y : 1)
sage: p1+p1 == p1*2
True
sage: p2*2
(1 : 1 : 1)
sage: p2+p2
(1 : 1 : 1)
#-----------------------
# Test point at infinity
#-----------------------
sage: p2 = E.point((y^3, y^2 + y + 1, 1))
sage: p1+p2
(0 : 1 : 0)
sage: p3 = p1+p2
sage: p3.xy()
---------------------------------------------------------------------------
ZeroDivisionError
"""
result = ar.ecgf2m_add_point(0b1000,0b1111,0b111,0b111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(0b111,0b111,0b1000,0b1111,0b10011)
self.assertEqual(result, (0b1100, 0b110))
result = ar.ecgf2m_add_point(0b1000,0b1111,0b1000,0b111,0b10011)
self.assertEqual(result, (0b0, 0b0)) #point at infinity
def affine_point_mul(self, k, x, y):
Q = (0,0) # point at infinity
first = True
for i in range(0,k.bit_length()):
Q = ar.ecgf2m_dbl_point(Q[0],Q[1],self._fx,self._a)
if (ar._bittest(k,(k.bit_length()-1) - i) == 0b1):
if (first):
Q = (x,y)
first = False
else:
Q = ar.ecgf2m_add_point(Q[0],Q[1],x,y,self._fx,self._a)
#print "DBG:\ni=%d\nQ[0]=%s\nQ[1]=%s\n" % (i,hex(Q[0]),hex(Q[1]))
return Q
def affine_point_mul(self, k, x, y):
Q = (0, 0) # point at infinity
first = True
for i in range(0, k.bit_length()):
Q = ar.ecgf2m_dbl_point(Q[0], Q[1], self._fx, self._a)
if (ar._bittest(k, (k.bit_length() - 1) - i) == 0b1):
if (first):
Q = (x, y)
first = False
else:
Q = ar.ecgf2m_add_point(Q[0], Q[1], x, y, self._fx,
self._a)
#print "DBG:\ni=%d\nQ[0]=%s\nQ[1]=%s\n" % (i,hex(Q[0]),hex(Q[1]))
return Q
