def decode(self, S, D, N):
self.Y = self.m
if int.from_bytes(self.Y, 'big') >= self.P:
for i in range(0, self.m.__len__()):
self.W[i] = lab1.fastModuloExponentiation(S[i], D, N)
else:
self.W = lab1.fastModuloExponentiation(S, D, N)
def encode(self):
if int.from_bytes(self.m, 'big') >= self.P:
for i in range(0, self.m.__len__()):
self.S[i] = lab1.fastModuloExponentiation(
self.Y[i], self.C, self.N)
else:
self.S = lab1.fastModuloExponentiation(self.m, self.C, self.N)
def el_gamal(p, g, m):
if not isPrime(p): sys.exit('ERROR. [P] must be prime number or p <= 255.')
Ca = random.randint(1, p - 1)
Cb = random.randint(1, p - 1) # Алгоритм евлкида
Cd = random.randint(1, p - 1)
Da = lab1.fastModuloExponentiation(g, Ca, p)
Db = lab1.fastModuloExponentiation(g, Cb, p)
Dc = lab1.fastModuloExponentiation(g, Cd, p)
# Зачем нужны Ca, Cd, Da, Dc пока что не разобрался, но в методичке они есть
if int.from_bytes(m, 'big') >= p:
k = [0] * m.__len__()
r = [0] * m.__len__()
mx = [0] * m.__len__()
e = [0] * m.__len__()
for i in range(0, m.__len__()):
k[i] = random.randint(1, p - 2)
r[i] = lab1.fastModuloExponentiation(g, k[i], p)
e[i] = m[i] * lab1.fastModuloExponentiation(Db, k[i], p) % p
mx[i] = e[i] * lab1.fastModuloExponentiation(r[i], p - 1 - Cb,
p) % p
out = bytearray(mx)
with open("elGamal_out.mp3", 'wb') as f:
f.write(out)
for i in range(0, m.__len__()):
if mx[i] == m[i]:
print(mx[i], ' == ', m[i])
continue
else:
print(mx[i], ' != ', m[i])
print("Error!")
return False
print("Successful!")
return True
else:
k = random.randint(1, p - 2)
r = lab1.fastModuloExponentiation(g, k, p)
e = m * lab1.fastModuloExponentiation(Db, k, p) % p
mx = e * lab1.fastModuloExponentiation(r, p - 1 - Cb, p) % p
if m == mx:
print(m, ' == ', mx)
print("Successful!")
return True
print(m, ' != ', mx)
print("Error!")
return False
def encode(self):
self.r = lab1.fastModuloExponentiation(self.g, self.k, self.p)
print('r = ', self.r)
if int.from_bytes(self.h, 'big') >= self.p:
for i in range(0, self.h.__len__()):
# print(2)
self.u[i] = (self.h[i] - self.x * self.r) % (self.p - 1)
self.k_tmp[i] = lab1.mulinv(self.k, self.p - 1)
self.s[i] = self.k_tmp[i] * self.u[i] % (self.p - 1)
else:
self.u = (self.h - self.x * self.r) % (self.p - 1)
self.k_tmp = lab1.mulinv(self.k, self.p - 1)
self.s = self.k_tmp * self.u % (self.p - 1)
def shamir_secret(m, p):
if not (isPrime(p) and (p > 255)):
sys.exit('ERROR. [P] must be prime number or p <= 255.')
Ca = lab1.generate_g(p)
Cb = lab1.generate_g(p)
Da = lab1.genEuclideanAlgo(Ca, p - 1)[1]
Db = lab1.genEuclideanAlgo(Cb, p - 1)[1]
if int.from_bytes(m, 'big') >= p:
x1 = [0] * m.__len__()
x2 = [0] * m.__len__()
x3 = [0] * m.__len__()
x4 = [0] * m.__len__()
for i in range(0, m.__len__()):
x1[i] = lab1.fastModuloExponentiation(m[i], Ca, p)
x2[i] = lab1.fastModuloExponentiation(x1[i], Cb, p)
x3[i] = lab1.fastModuloExponentiation(x2[i], Da, p)
x4[i] = lab1.fastModuloExponentiation(x3[i], Db, p)
# Проверка на равность полученного сообщения и изначального
out = bytearray(x4)
with open("Shamir_out.gif", 'wb') as f:
f.write(out)
for i in range(0, m.__len__()):
if x4[i] == m[i]:
print(x4[i], ' == ', m[i])
continue
else:
print(x4[i], ' != ', m[i])
print("Error!")
return False
print("Successful!")
return True
else:
x1 = lab1.fastModuloExponentiation(int.from_bytes(m, 'big'), Ca, p)
x2 = lab1.fastModuloExponentiation(x1, Cb, p)
x3 = lab1.fastModuloExponentiation(x2, Da, p)
x4 = lab1.fastModuloExponentiation(x3, Db, p)
# Проверка на равность полученного сообщения и изначального
if not x4 == int.from_bytes(m, 'big'):
print(x4, ' != ', m)
print("Error!")
return False
print(x4, ' == ', m)
print("Successful!")
return True
def __init__(self, p, g, m):
self.p = p
self.g = g
self.h = m
self.x = lab1.generate_g(p - 2)
self.y = lab1.fastModuloExponentiation(self.g, self.x, self.p)
self.k = lab1.generate_g(p - 2)
print(lab1.genEuclideanAlgo(self.k, p - 1))
self.r = 0
if int.from_bytes(self.h, 'big') >= self.p:
self.u = [0] * m.__len__()
self.s = [0] * m.__len__()
self.k_tmp = [0] * m.__len__()
else:
self.r = 0
self.u = 0
self.s = 0
self.k_tmp = 0
def decode(self, r, s):
left = 0
right = 0
if int.from_bytes(self.h, 'big') >= self.p:
left = [0] * self.h.__len__()
right = [0] * self.h.__len__()
# print('r = ', r)
# print('s = ', s)
# print('p = ', self.p)
for i in range(0, self.h.__len__()):
left[i] = lab1.fastModuloExponentiation(self.y, r, self.p) * \
lab1.fastModuloExponentiation(r, s[i], self.p)
right[i] = lab1.fastModuloExponentiation(
self.g, self.h[i], self.p)
else:
left = lab1.fastModuloExponentiation(
self.y, r, self.p) * lab1.fastModuloExponentiation(
r, s, self.p)
right = lab1.fastModuloExponentiation(self.g, self.h, self.p)
return left, right
def decrypt(self, e):
mx = [0] * e.__len__()
for i in range(0, e.__len__()):
mx[i] = lab1.fastModuloExponentiation(e[i], self.C, self.N)
return mx
def encrypt(self, D, N):
e = [0] * self.m.__len__()
for i in range(0, self.m.__len__()):
e[i] = lab1.fastModuloExponentiation(self.m[i], D, N)
return e
