def random_minicipher(n):
res = []
for k in xrange(2**n):
p = range(2**n)
shuffle(p)
res.append(tuple(p))
return tuple(res)
def random_involution(n):
print 'WARNING: too low number of fixed points! not a uniform distribution'
pairs = range(2**n)
shuffle(pairs)
s = [0] * 2**n
while pairs:
if len(pairs) == 1 or randint(1, len(pairs)) == 1:
a = b = pairs.pop()
else:
a, b = pairs.pop(), pairs.pop()
s[a] = b
s[b] = a
return s
def generate_FN(funcpool, nr):
shuffle(funcpool)
fs = funcpool[:nr]
s = SBox2.gen.feistel_network_xor(funcs=fs)
return fs, s
def generate_FN_two_last(funcpool, nr):
shuffle(funcpool)
fs = funcpool[:nr]
s = SBox2.gen.feistel_network_xor(funcs=fs)
spre = SBox2.gen.feistel_network_xor(funcs=fs[:-1])
return fs, s, spre
def random_permutation(n, h**o=False):
res = range(1 if h**o else 0, 2**n)
shuffle(res)
return ([0] if h**o else []) + res
