def share_string_to_point(share_string, charset):
""" Convert a share string to a point (a tuple of integers).
"""
# share should be in the format "01-d051080de7..."
if '-' in charset:
raise ValueError(
'The character "-" cannot be in the supplied charset.')
if not isinstance(share_string, str) and share_string.count('-') == 1:
raise ValueError('Share format is invalid.')
x_string, y_string = share_string.split('-')
if (set(x_string) - set(charset)) or (set(y_string) - set(charset)):
raise ValueError("Share has characters that aren't in the charset.")
if (isinstance(x_string, bytes)):
temp = str(x_string)
x_string = ""
for i in range(2, len(temp) - 1):
x_string += temp[i]
if (isinstance(y_string, bytes)):
temp = str(y_string)
y_string = ""
for i in range(2, len(temp) - 1):
y_string += temp[i]
x = charset_to_int(x_string, charset)
y = charset_to_int(y_string, charset)
return (x, y)
def share_string_to_point(share_string, charset):
""" Convert a share string to a point (a tuple of integers).
"""
# share should be in the format "01-d051080de7..."
if '-' in charset:
raise ValueError(
'The character "-" cannot be in the supplied charset.')
if not isinstance(share_string, str) and share_string.count('-') == 1:
raise ValueError('Share format is invalid.')
x_string, y_string = share_string.split('-')
if (set(x_string) - set(charset)) or (set(y_string) - set(charset)):
raise ValueError("Share has characters that aren't in the charset.")
x_val = charset_to_int(x_string, charset)
y_val = charset_to_int(y_string, charset)
return (x_val, y_val)
def share_string_to_point(share_string, charset):
""" Convert a share string to a point (a tuple of integers).
"""
# share should be in the format "01-d051080de7..."
if '-' in charset:
raise ValueError(
'The character "-" cannot be in the supplied charset.')
if not isinstance(share_string, str) and share_string.count('-') == 1:
raise ValueError('Share format is invalid.')
x_string, y_string = share_string.split('-')
if (set(x_string) - set(charset)) or (set(y_string) - set(charset)):
raise ValueError("Share has characters that aren't in the charset.")
x = charset_to_int(x_string, charset)
y = charset_to_int(y_string, charset)
return (x, y)
def split_secret(cls, secret_string, share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
shares = []
for point in points:
shares.append(point_to_share_string(point, cls.share_charset))
return shares
def split_secret(cls, secret_string, share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
shares = []
for point in points:
shares.append(point_to_share_string(point, cls.share_charset))
return shares
def _generate_and_record_params_for_secret(self, secret_string,
share_threshold, max_shares):
secret_int = charset_to_int(secret_string, self.secret_charset)
prime = get_large_enough_prime([secret_int, max_shares])
coefficients = random_polynomial(share_threshold - 1, secret_int,
prime)
self._record_params_for_secret(secret_string, secret_int, prime,
coefficients)
def split_secret_get_shares_and_modulus(cls, secret_string,
share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
prime = get_large_enough_prime([secret_int, num_shares])
points = secret_int_to_points(secret_int, share_threshold, num_shares,
prime)
shares = []
for point in points:
shares.append(point_to_share_string(point, cls.share_charset))
return (shares, prime)
def split_secret(cls, secret_string, share_threshold, num_shares):
if (isinstance(secret_string, bytes)):
temp = str(secret_string)
secret_string = ""
for i in range(2, len(temp) - 1):
secret_string += temp[i]
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
shares = []
for point in points:
shares.append(point_to_share_string(point, cls.share_charset))
return shares
def split_secret(cls, secret_string, share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
shares = []
for point in points:
shares.append(point_to_share_string(point, cls.share_charset))
recovered = cls.recover_secret(shares)
if secret_string != recovered:
raise ValueError(
'Shares did not recover secret. Check that secret does not begin with "{}"'
.format(cls.secret_charset[0]))
return shares
def test_deadbeef_to_int(self):
s = "deadbeef"
value = charset_to_int(s, base16_chars)
reference_value = int(s, 16)
self.assertEqual(value, reference_value)
def split_secret(cls, secret_string, share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
point_to_share_fn = rpartial(point_to_share_string, cls.share_charset)
return lmap(point_to_share_fn, points)
def split_secret(cls, secret_string, share_threshold, num_shares):
secret_int = charset_to_int(secret_string, cls.secret_charset)
points = secret_int_to_points(secret_int, share_threshold, num_shares)
return cls.points_to_shares(points)
