def to_point(point_f):
""" Create a new Point instance (value-copy) from the given PointF. """
assert (isinstance(point_f, PointF))
return Point.copy(point_f)
def main():
"""
Driver code
"""
# Parser Routine
parser = argparse.ArgumentParser(description=
"""
Elliptic Curves in Jacobian Coordinates
"""
)
# pylint: disable=line-too-long,invalid-name
parser.add_argument("-a", action="store", type=int, help="This is the value a in y^2 = x^3 + ax + b mod m", required=False)
parser.add_argument("-b", action="store", type=int, help="This is the value b in y^2 = x^3 + ax + b mod m", required=False)
parser.add_argument("-m", action="store", type=int, help="This is the value m in y^2 = x^3 + ax + b mod m", required=False)
parser.add_argument("-i", action="store", type=str, help="Input curve, space delimitted a,b,m in a file. File name", required=False)
parser.add_argument("-px", action="store", type=int, help="This is the point value x for the generator", required=False)
parser.add_argument("-py", action="store", type=int, help="This is the point value y for the generator", required=False)
parser.add_argument("-pz", action="store", type=int, help="This is the point value z for the generator", required=False)
parser.add_argument("-o", action="store", type=str, help="This is the path of the output file; stdout is default", required=False)
parser.add_argument("--bv", action="store_true", help="This is verbose brute force", required=False)
parser.add_argument("--brute", action="store_true", help="If the curve does not have order p where p is prime, the shortcut\
is rendered useless, and exhaustive search can be done", required=False)
parser.add_argument("--affine", action="store_true", help="For point generation, this converts all the points to affine(very slow)")
args = parser.parse_args()
x = args.px
y = args.py
z = args.pz
bv = args.bv
brute = args.brute or bv
affine = args.affine
inputfile = args.i
o = args.o if args.o else "/dev/tty"
with open(o, "w") as f:
a = None
b = None
m = None
# Parse Arguments
if inputfile:
try:
with open(inputfile, "r") as inputty:
try:
(a,b,m) = [int(i) for i in inputty.readline().split()]
except _:
f.write("Curve was unparseable\n")
exit(1)
except _:
f.write("File {} is unreadable\n".format(inputfile))
exit(1)
else:
a = args.a
b = args.b
m = args.m
if not(a and b and m):
f.write("No curve selected\n")
exit(1)
curve = Curve(a,b,m)
# Point Routine
# Go through order of point
if x is not None:
# we have a point
z = z if z else 1
point = Point(x,y,z,curve) if y else curve.point_from_x(x)
if isinstance(point, list):
if len(point) == 0:
f.write("This curve {} does not have a point at x = {}\n".format(curve, x))
exit(1)
else:
point = point[0]
if point not in curve:
f.write("This point {} is not on the curve {}\n".format(point, curve))
exit(1)
for (i, kpoint) in enumerate(point.order_multiplication_generator()):
if affine:
kpoint.convert_to_affine()
s = "{}p = {}\n".format(i, kpoint)
f.write(s)
# Curve Routine
else:
count_of_max_points = 0
for (i, point) in enumerate(curve.all_points()):
f.write("{}\n".format(point))
count_of_points = len(curve.points)
f.write("{}\nThe curve\n{}\nhas {} affine points:\n".format("-"*80, curve, count_of_points))
if not brute:
f.write("The points with order {}(assuming {} is prime, this is the maximum order of the group) are: \n{}\n".format(count_of_points, count_of_points, "-"*80))
# Lots of redundancy here
for point in curve.all_points():
if not point.infinity:
opposite_point = point * (count_of_points - 1)
if not opposite_point.infinity:
opposite_point.convert_to_affine()
if opposite_point.x == point.x:
if (opposite_point + point).infinity:
count_of_max_points += 1
f.write("{}\n".format(point, count_of_points))
f.write("{}\nThere are {} points with order {}\n".format("-"*80, count_of_max_points, count_of_points))
else:
# Brute force
max_order = 0
max_points = []
for point in curve.all_points():
if point.infinity:
continue
if bv:
f.write("The order for the point {} on curve {}\n{}\n".format(point, curve, "-"*80))
exponentiation = point.copy()
i = 0
if bv:
f.write("{}p = {}\n".format(i, Point.infinity()))
while not exponentiation.infinity:
i += 1
if bv:
f.write("{}p = {}\n".format(i, exponentiation))
exponentiation += point
if bv:
f.write("{}p = {}\n".format(i+1, exponentiation))
if i > max_order:
max_points = [point]
max_order = i
elif i == max_order:
max_points.append(point)
f.write("The points with max order {} are\n{}\n".format(max_order, "-"*80))
total_count = 0
for point in max_points:
f.write("{}\n".format(point))
total_count += 1
f.write("In total there are {} points with max order {}\n".format(total_count, count_of_points))
