def decrypt(self, filename, keyB_private):
ciphertext = self.read_file_list(filename)
process = PointOperatorECC(self._get_A(), self._get_B(), self._get_P())
key_pri = self.read_file_list(keyB_private)
kG = Point()
kG._set_x(ciphertext.pop(0))
kG._set_y(ciphertext.pop(0))
kGPub = process.multiply(key_pri, kG)
print("(x_pub, y_pub) : ", kGPub._get_x(), kGPub._get_y())
i = 0
list_plain_point = []
while i < len(ciphertext):
point_cipher = Point()
point_cipher._set_x(ciphertext[i])
point_cipher._set_y(ciphertext[i+1])
res = process.minus(point_cipher, kGPub)
print("(x , y, x_min, y_min) : ", ciphertext[i], ciphertext[i+1], res._get_x() , res._get_y())
list_plain_point.append(res)
i+=2
# for i in range(len(list_plain_point)):
# print(list_plain_point[i]._get_x(), list_plain_point[i]._get_y())
list_plain_int = self.decoding(list_plain_point)
print(list_plain_int)
regex = re.compile('.\w+').findall(filename)
self.write_file_list("out_ecceg" + regex[-1], list_plain_int)
def add(self, p1, p2):
result = Point()
if p1._get_x() == 0 and p1._get_y() == 0:
result._set_x(p2._get_x())
result._set_x(p2._get_y())
elif p2._get_x() == 0 and p2._get_y() == 0:
result._set_x(p1._get_x())
result._set_x(p1._get_y())
elif p1._get_y() - p2._get_y() == 0:
result._set_x((0 - p1._get_x() - p2._get_x()) % self._get_P())
result._set_x((0 - p1._get_x()) % self._get_P())
elif p1._get_x() - p2._get_x() == 0:
result._set_x(sys.maxsize)
result._set_y(sys.maxsize)
else:
inv = inverse((p1._get_x() - p2._get_x()), self._get_P())
lamda = ((p1._get_y() - p2._get_y()) * inv) % self._get_P()
xr = (lamda**2 - p1._get_x() - p2._get_x()) % self._get_P()
yr = (lamda * (p1._get_x() - xr) - p1._get_y()) % self._get_P()
result._set_x(xr)
result._set_y(yr)
return result
def generate_galois_field(self):
field = []
for i in range(self._get_P()):
list_y = self.compute_ecc_equation(i)
if list_y:
for j in range(len(list_y)):
point = Point()
point._set_x(i)
point._set_y(list_y[j])
field.append(point)
return field
def encoding(self, list_message):
result = []
for i in range(len(list_message)):
for j in range(self._get_k()-1):
x = (list_message[i] * self._get_k() + (j + 1))
y = self.compute_ecc_equation(x)
# print(x ,y)
if y:
point = Point()
point._set_x(x)
point._set_y(y[0])
result.append(point)
break
return result
def encrypt(self, filename, keyB_public, keyB_private, k):
plaintext = self.read_file(filename)
list_plaintext = list(plaintext)
list_plain_int = list(map(int, plaintext))
print(list_plain_int)
key_pub = self.read_file_list(keyB_public)
point_key_pub = Point()
point_key_pub._set_x(key_pub[0])
point_key_pub._set_y(key_pub[1])
print("(x_pubB, y_pubB) : ", point_key_pub._get_x(), point_key_pub._get_y())
list_message_point = self.encoding(list_plain_int)
# print(self.decoding(list_message_point))
key_pri = self.read_file_list(keyB_private)
process = PointOperatorECC(self._get_A(), self._get_B(), self._get_P())
field = self.generate_galois_field()
# Base point in galois field[0]
base = field[0]
# for i in range(len(list_message_point)):
# print(list_message_point[i]._get_x(), list_message_point[i]._get_y())
# K value, different from k for encoding
kG = process.multiply(k, base)
priG = process.multiply(key_pri, base)
print("(x_priG, y_priG) : ", priG._get_x(), priG._get_y())
keyPub = process.multiply(key_pri, kG) #8x9
print(key_pri)
print("(x_pripub, y_pripub) : ", keyPub._get_x(), keyPub._get_y())
kGPub = process.multiply(k, priG) #9x8
print(k)
print("(x_pub, y_pub) : ", kGPub._get_x(), kGPub._get_y())
cipher = []
cipher.append(kG._get_x())
cipher.append(kG._get_y())
for i in range(len(list_message_point)):
msg_cipher = process.add(list_message_point[i], kGPub)
print("(x, y, x_add, y_add) : ", list_message_point[i]._get_x(), list_message_point[i]._get_y(), msg_cipher._get_x(), msg_cipher._get_y())
cipher.append(msg_cipher._get_x())
cipher.append(msg_cipher._get_y())
print("==============================================================")
regex = re.compile('.\w+').findall(filename)
self.write_file_list("cipher_ecceg" + regex[-1], cipher)
def double_point(self, p):
result = Point()
if p._get_y() == 0:
result._set_x(sys.maxsize)
result._set_y(sys.maxsize)
else:
inv = inverse(2 * p._get_y(), self._get_P())
lamda = ((3 *
(p._get_x())**2 + self._get_A()) * inv) % self._get_P()
lamda = int(lamda % self._get_P())
# print(lamda)
xr = (lamda**2 - (2 * p._get_x())) % self._get_P()
# print(xr)
yr = (lamda * (p._get_x() - xr) - p._get_y()) % self._get_P()
# print(yr)
result._set_x(int(xr))
result._set_y(int(yr))
return result
result._set_x((0 - p1._get_x()) % self._get_P())
elif p1._get_x() - p2._get_x() == 0:
result._set_x(sys.maxsize)
result._set_y(sys.maxsize)
else:
inv = inverse((p1._get_x() - p2._get_x()), self._get_P())
lamda = ((p1._get_y() - p2._get_y()) * inv) % self._get_P()
xr = (lamda**2 - p1._get_x() - p2._get_x()) % self._get_P()
yr = (lamda * (p1._get_x() - xr) - p1._get_y()) % self._get_P()
result._set_x(xr)
result._set_y(yr)
return result
if __name__ == '__main__':
point = Point()
point._set_x(2)
point._set_y(4)
# p1 = Point()
# p1._set_x(2)
# p1._set_y(4)
# p2 = Point()
# p2._set_x(5)
# p2._set_y(9)
op = PointOperatorECC(1, 6, 11)
result = op.double_point(point)
print(result._get_x(), result._get_y())