def test_dlrep_non_interactive_1(group):
g, h = make_generators(2, group)
expr = Secret(value=3) * g + Secret(value=4) * h
p = DLRep(expr.eval(), expr)
tr = p.prove()
prover = p.get_prover()
assert p.verify(tr)
def commit(self, messages, zkp=True):
"""
Construct the product of messages and optionaly a Pedersen commitment and its proof.
Args:
messages: Messages (attributes) to commit to
zkp (bool): Whether to construct a Pedersen commitment and proof the knowledge of the
messages for this commitment.
Returns:
:py:class:`UserCommitmentMessage`: user's packed commitment.
"""
lhs = self.pk.generators[0].group.wsum(
messages, self.pk.generators[2 : len(messages) + 2]
)
com_nizk_proof = None
if zkp:
self.s1 = self.pk.generators[0].group.order().random()
lhs = self.s1 * self.pk.generators[1] + lhs
# TODO: Extract into a separate ExtendedProofStmt.
secret_vars = [Secret() for _ in range(len(messages) + 1)]
secrets = [self.s1] + messages
rhs = wsum_secrets(secret_vars, self.pk.generators[1 : len(messages) + 2])
com_stmt = DLRep(lhs, rhs)
com_nizk_proof = com_stmt.prove(
{s: v for s, v in zip(secret_vars, secrets)}
)
return UserCommitmentMessage(com_message=lhs, com_nizk_proof=com_nizk_proof)
def test_dlrep_non_interactive_with_message(group):
g, h = make_generators(2, group)
expr = Secret(value=3) * g + Secret(value=4) * h
p = DLRep(expr.eval(), expr)
tr = p.prove(message="mymessage")
assert DLRep(expr.eval(), expr).verify(tr, message="mymessage")
def test_dlrep_bad_hash(group):
g, h = make_generators(2, group=group)
x, y = Secret(), Secret()
secret_dict = {x: 2, y: 3}
p1 = DLRep(2 * g + 3 * h, x * g + y * h)
p2 = DLRep(2 * g + 3 * h, y * h + x * g)
tr = p1.prove(secret_dict)
assert p1.verify(tr)
with pytest.raises(StatementMismatch):
p2.verify(tr)
def test_dlrep_wrong_response_non_interactive(group):
g, h = make_generators(2, group=group)
x, y = Secret(value=3), Secret(value=4)
expr = x * g + y * h
p = DLRep(expr.eval(), expr)
tr = p.prove(message="mymessage")
# Turn one of the responses random
tr.responses[1] = group.order().random()
assert not p.verify(tr, message="mymessage")
def test_dlrep_non_interactive_2(group):
(g, ) = make_generators(1, group)
x = Secret()
p = DLRep(4 * g, x * g)
tr = p.prove({x: 4})
assert p.verify(tr)