def create_tumbler_checker(inputs, reference_inputs, parameters, outputs, returns, dependencies):
try:
# retrieve ID list
spent_list = loads(outputs[1])
# retrieve vvk & sig
packed_vvk = spent_list['vvk']
sig = pet_unpack(parameters[0])
# check format
if len(inputs) != 1 or len(reference_inputs) != 0 or len(outputs) != 2 or len(returns) != 0:
return False
# check types
if loads(inputs[0])['type'] != 'TToken' or loads(outputs[0])['type'] != 'TToken': return False
if spent_list['type'] != 'TList': return False
# verify that the spent list is empty
if spent_list['list']: return False
# verify signature
bp_params = bp_setup()
hasher = sha256()
hasher.update(outputs[1].encode('utf8'))
m = Bn.from_binary(hasher.digest())
vvk = (unpackG2(bp_params,packed_vvk[0]), unpackG2(bp_params,packed_vvk[1]), unpackG2(bp_params,packed_vvk[2]))
if not verify(bp_params, vvk, m, sig): return False
# otherwise
return True
except (KeyError, Exception):
return False
def verify_checker(inputs, reference_inputs, parameters, outputs, returns,
dependencies):
try:
# retrieve data
instance = loads(reference_inputs[0])
# check format
if len(inputs) != 0 or len(reference_inputs) != 1 or len(
outputs) != 0 or len(returns) != 1:
return False
# verify signature
params = setup(instance['q'])
packed_sig = parameters[0]
sig = (unpackG1(params,
packed_sig[0]), unpackG1(params, packed_sig[1]))
clear_m = loads(parameters[1])
kappa = unpackG2(params, parameters[2])
proof_v = pet_unpack(parameters[3])
packed_vvk = instance['verifier']
vvk = (unpackG2(params,
packed_vvk[0]), unpackG2(params, packed_vvk[1]),
[unpackG2(params, y) for y in packed_vvk[2]])
if not mix_verify(params, vvk, kappa, sig, proof_v, clear_m):
return False
# otherwise
return True
except (KeyError, Exception):
return False
def create_checker(inputs, reference_inputs, parameters, outputs, returns,
dependencies):
try:
# retrieve instance
instance = loads(outputs[1])
# retrieve parameters
packed_sig = parameters[0]
# check format
if len(inputs) != 1 or len(reference_inputs) != 0 or len(
outputs) != 2 or len(returns) != 0:
return False
# check types
if inputs[0] != outputs[0]: return False
if instance['type'] != 'CoCoInstance': return False
# check fields
q = instance['q']
t = instance['t']
n = instance['n']
instance['callback']
packed_vvk = instance['verifier']
if q < 1 or n < 1 or t > n: return False
# verify signature
params = setup(q)
sig = (unpackG1(params,
packed_sig[0]), unpackG1(params, packed_sig[1]))
vvk = (unpackG2(params,
packed_vvk[0]), unpackG2(params, packed_vvk[1]),
[unpackG2(params, y) for y in packed_vvk[2]])
hasher = sha256()
hasher.update(outputs[1].encode('utf8'))
m = Bn.from_binary(hasher.digest())
if not mix_verify(params, vvk, None, sig, None, [m]): return False
# otherwise
return True
except (KeyError, Exception):
return False
def verify(inputs, reference_inputs, parameters, clear_m, hidden_m):
#start_time = time.time()
# load instance
instance = loads(reference_inputs[0])
# build proof
params = setup(instance['q'])
packed_vvk = instance['verifier']
vvk = (unpackG2(params, packed_vvk[0]), unpackG2(params, packed_vvk[1]),
[unpackG2(params, y) for y in packed_vvk[2]])
(kappa, proof_v) = show_mix_sign(params, vvk, hidden_m)
tnm = (dumps(clear_m), pack(kappa), pet_pack(proof_v))
#end_time = time.time(); print((end_time-start_time)*1000)
# returns
return {
'returns': (dumps(True), ),
'extra_parameters': (dumps(clear_m), pack(kappa), pet_pack(proof_v))
}
def redeem_checker(inputs, reference_inputs, parameters, outputs, returns, dependencies):
try:
# retrieve ID list
old_list = loads(inputs[0])
new_list = loads(outputs[0])
# retrieve parameters
bp_params = bp_setup()
ID = loads(parameters[0])
merchant_addr = loads(parameters[1])
packed_sig = parameters[2]
sig = (unpackG1(bp_params, packed_sig[0]), unpackG1(bp_params, packed_sig[1]))
# check format
if len(inputs) != 1 or len(reference_inputs) != 0 or len(outputs) != 1 or len(returns) != 0:
return False
# check types
if new_list['type'] != 'TList': return False
# check format & consistency with old object
packed_vvk = new_list['vvk']
if new_list['vvk'] != new_list['vvk']: return False
# check spent list
if (ID in old_list['list']) or (new_list['list'] != old_list['list'] + [ID]):
return False
# verify signature and nu's correctness
vvk = (unpackG2(bp_params,packed_vvk[0]), unpackG2(bp_params,packed_vvk[1]), unpackG2(bp_params,packed_vvk[2]))
hasher = sha256()
hasher.update(parameters[0].encode('utf8'))
hasher.update(parameters[1].encode('utf8'))
m = Bn.from_binary(hasher.digest())
if not verify(bp_params, vvk, m, sig): return False
# otherwise
return True
except (KeyError, Exception):
return False
def sign_checker(inputs, reference_inputs, parameters, outputs, returns,
dependencies):
try:
# retrieve petition
old_petition = loads(inputs[0])
new_petition = loads(outputs[0])
# retrieve ID list
old_list = loads(inputs[1])
new_list = loads(outputs[1])
# retrieve parameters
bp_params = bp_setup()
new_values = loads(parameters[0])
packed_sig = parameters[1]
sig = (unpackG1(bp_params,
packed_sig[0]), unpackG1(bp_params, packed_sig[1]))
kappa = unpackG2(bp_params, parameters[2])
nu = unpackG1(bp_params, parameters[3])
proof_v = pet_unpack(parameters[4])
# check format
if len(inputs) != 2 or len(reference_inputs) != 0 or len(
outputs) != 2 or len(returns) != 0:
return False
# check types
if new_petition['type'] != 'PObject' or new_list['type'] != 'PList':
return False
# check format & consistency with old object
UUID = pet_unpack(new_petition['UUID'])
options = new_petition['options']
packed_vvk = new_petition['verifier']
scores = new_petition['scores']
if old_petition['UUID'] != new_petition['UUID']: return False
if len(old_petition['owner']) != len(new_petition['owner']):
return False
if len(old_petition['options']) != len(new_petition['options']):
return False
if old_petition['verifier'] != new_petition['verifier']: return False
# check new values
if sum(new_values) != 1: return False
for i in range(len(scores)):
if scores[i] != old_petition['scores'][i] + new_values[i]:
return False
if new_values[i] != 0 and new_values[i] != 1: return False
# check spent list
packed_nu = parameters[3]
if (packed_nu in old_list['list']) or (new_list['list'] !=
old_list['list'] + [packed_nu]):
return False
# verify signature and nu's correctness
vvk = (unpackG2(bp_params,
packed_vvk[0]), unpackG2(bp_params, packed_vvk[1]),
unpackG2(bp_params, packed_vvk[2]))
if not coconut_petition_verify(bp_params, vvk, kappa, sig, proof_v,
UUID, nu):
return False
# otherwise
return True
except (KeyError, Exception):
return False