def test_raises_value_error_on_message_not_less_than_p(self):
m = 3
k = 3
n = 3
p = 3
with self.assertRaises(ValueError):
shamir.encode(message=m, k=k, n=n, p=p)
def test_raises_value_error_on_n_greater_or_equal_p(self):
m = 6
k = 4
p = 7
with self.assertRaises(ValueError):
shamir.encode(message=m, k=k, n=p, p=p)
with self.assertRaises(ValueError):
shamir.encode(message=m, k=k, n=p + 1, p=p)
def test_decoded_equals_original_message(self):
message = 10
k = 10
n = 11
p = 13
shares = shamir.encode(message=message, k=k, n=n, p=p)
decoded = shamir.decode(shares=shares, k=k, p=p)
self.assertEqual(message, decoded)
def test_encoding_large_strings(self):
k = 3
n = 5
p = 2 ** 521 - 1 # 13th Mersenne prime
string = 'This is a pretty long secret message. Big field order is needed.'
integer = shamir.str_to_int(string)
shares = shamir.encode(integer, k=k, n=n, p=p)
recovered_integer = shamir.decode(shares, k=k, p=p)
recovered_string = shamir.int_to_str(recovered_integer)
self.assertEqual(string, recovered_string)
def test_decoded_str_equals_original(self):
k = 3
n = 5
p = 2 ** 61 - 1 # 9th Mersenne prime
string = 'message'
integer = shamir.str_to_int(string)
shares = shamir.encode(integer, k=k, n=n, p=p)
recovered_integer = shamir.decode(shares, k=k, p=p)
recovered_string = shamir.int_to_str(recovered_integer)
self.assertEqual(string, recovered_string)
def test_different_permutations_of_shares_give_the_same_result(self):
message = 10
k = 3
n = 4
p = 13
shares = shamir.encode(message=message, k=k, n=n, p=p)
for permutation in permutations(shares):
decoded = shamir.decode(shares=permutation, k=k, p=p)
self.assertEqual(message, decoded)
def calc_shares(self):
try:
secret = self.edit_secret.text()
n = int(self.edit_n.text())
k = int(self.edit_k.text())
if k > n:
error_message = QErrorMessage(self)
error_message.showMessage('minimalna liczba fragmentów nie może być większa niż '
'całkowita liczba fragmentów')
return
int_secret = shamir.str_to_int(secret)
if int_secret >= self.field_order:
error_message = QErrorMessage(self)
error_message.showMessage('podany sekret jest zbyt długi')
return
shares = shamir.encode(int_secret, k=k, n=n, p=self.field_order)
except ValueError:
print('wrong values')
return
shares_string = self.shares_to_string(shares)
self.edit_shares.setText(shares_string)
def test_raises_value_error_on_k_greater_than_n(self):
m = 2
n = 5
p = 7
with self.assertRaises(ValueError):
shamir.encode(message=m, k=n + 1, n=n, p=p)