def test_robust_bad_configuration_prime_none():
num_players = 40
reconstruction_threshold = 30
players = get_ids(num_players)
with pytest.raises(ValueError):
rss.share_authenticated_secret(players, reconstruction_threshold, 5000, secret)
def test_robust_bad_configuration_threshold():
num_players = 2
reconstruction_threshold = 5
players = get_ids(num_players)
max_secret_length = len(secret)
with pytest.raises(ValueError):
rss.share_authenticated_secret(players, reconstruction_threshold, max_secret_length, secret)
def test_robust_bad_configuration_prime_small_secret():
num_players = 5
reconstruction_threshold = 2
players = get_ids(num_players)
bad_secret = '\xFF\xFF'
max_secret_length = len(bad_secret) - 1
with pytest.raises(ValueError):
rss.share_authenticated_secret(players, reconstruction_threshold, max_secret_length, bad_secret)
def share_and_recover(num_players, reconstruction_threshold, secret, end):
max_secret_length = len(secret)
players = test_authenticated_rss.get_ids(num_players)
robust_shares = rss.share_authenticated_secret(players, reconstruction_threshold, max_secret_length, secret)
shares = {player: share for (player, share) in robust_shares.items()[:end]}
return rss.reconstruct_unauthenticated_secret(num_players, max_secret_length, shares)
def test_min_shares_some_bad():
num_players = 9
reconstruction_threshold = 5
num_bad = 2
max_secret_length = len(secret)
players = test_authenticated_rss.get_ids(num_players)
robust_shares = rss.share_authenticated_secret(players, reconstruction_threshold, max_secret_length, secret)
result = corrupt_and_recover(robust_shares, num_players, num_players, num_bad)
assert result is None or result != secret
def get_shares_subset(players, reconstruction_threshold, secret, end):
'''
Args:
players, a list of random, unique ids
reconstruction_threshold, the threshold used for sharing
secret, the value to be secret shared
end, marks the number of shares to return
Returns:
a dictionary of length end that maps ids to json_string shares
'''
max_secret_length = len(secret)
shares_map = rss.share_authenticated_secret(players, reconstruction_threshold, max_secret_length, secret)
return {player: shares_map[player] for player in shares_map.keys()[:end]}
def share(secret, player_ids, threshold):
"""
Construct shares of the given secret such that shares below the threshold
yield no information, but shares above the threshold recreate the secret.
Args:
secret: a binary string or other byte representation of the secret to be shared.
player_ids: a list of unique strings, one for each resulting share
threshold: the number of shares required to reconstruct the secret.
Returns:
A map from player_id to a share to give to that player, suitable to be passed into reconstruct
Raises:
LibraryException: an exception was thrown by the supporting sharing library
"""
try:
return rss.share_authenticated_secret(player_ids, threshold, len(secret), secret)
except ValueError:
logging.exception("Exception encountered during secret share creation")
raise exceptions.LibraryException
