def shuffle(x, config=None, value_type=sgf2n, reverse=False):
""" Simulate secure shuffling with Waksman network for 2 players.
Returns the network switching config so it may be re-used later. """
n = len(x)
if n & (n - 1) != 0:
raise CompilerError('shuffle requires n a power of 2')
if config is None:
config = permutation.configure_waksman(permutation.random_perm(n))
for i, c in enumerate(config):
config[i] = [value_type(b) for b in c]
permutation.waksman(x, config, reverse=reverse)
permutation.waksman(x, config, reverse=reverse)
return config
def shuffle(x, config=None, value_type=sgf2n, reverse=False):
""" Simulate secure shuffling with Waksman network for 2 players.
Returns the network switching config so it may be re-used later. """
n = len(x)
if n & (n-1) != 0:
raise CompilerError('shuffle requires n a power of 2')
if config is None:
config = permutation.configure_waksman(permutation.random_perm(n))
for i,c in enumerate(config):
config[i] = [value_type(b) for b in c]
permutation.waksman(x, config, reverse=reverse)
permutation.waksman(x, config, reverse=reverse)
return config
def config_shuffle_given_perm(perm, value_type=sint):
""" Compute config for oblivious shuffling.
Take mod 2 for active sec. """
n = len(perm)
if n & (n - 1) != 0:
# pad permutation to power of 2
m = 2 ** int(math.ceil(math.log(n, 2)))
perm += list(range(n, m))
config_bits = configure_waksman(perm)
# 2-D array
config = Array(len(config_bits) * len(perm), value_type.reg_type)
for i, c in enumerate(config_bits):
for j, b in enumerate(c):
config[i * len(perm) + j] = b
return config
def default_config_shuffle(values, use_iter=True):
"""Configures waksman network for default shuffle algorithm."""
if use_iter:
return config_shuffle_for_length(len(values))
else:
return configure_waksman(random_perm(len(values)))
