def test_vladimir_uses_his_own_signing_key(alice, mining_ursulas):
"""
Similar to the attack above, but this time Vladimir makes his own interface signature
using his own signing key, which he claims is Ursula's.
"""
his_target = list(mining_ursulas)[4]
vladimir_ether_address = '0xE57bFE9F44b819898F47BF37E5AF72a0783e1141'
fraduluent_keys = CryptoPower(power_ups=Ursula._default_crypto_powerups)
vladimir = Ursula(crypto_power=fraduluent_keys,
rest_host=his_target.rest_interface.host,
rest_port=his_target.rest_interface.port,
checksum_address=vladimir_ether_address,
is_me=False)
message = vladimir._signable_interface_info_message()
signature = vladimir._crypto_power.power_ups(SigningPower).sign(message)
vladimir._interface_signature_object = signature
vladimir.substantiate_stamp()
# With this slightly more sophisticated attack, his metadata does appear valid.
vladimir.validate_metadata()
# However, the actual handshake proves him wrong.
with pytest.raises(vladimir.InvalidNode):
vladimir.verify_node(alice.network_middleware)
def test_vladimir_cannot_verify_interface_with_ursulas_signing_key(
mining_ursulas):
his_target = list(mining_ursulas)[4]
# Vladimir has his own ether address; he hopes to publish it along with Ursula's details
# so that Alice (or whomever) pays him instead of Ursula, even though Ursula is providing the service.
vladimir_ether_address = '0xE57bFE9F44b819898F47BF37E5AF72a0783e1141'
# Vladimir imitates Ursula - copying her public keys and interface info, but inserting his ether address.
vladimir = Ursula(crypto_power=his_target._crypto_power,
rest_host=his_target.rest_interface.host,
rest_port=his_target.rest_interface.port,
checksum_address=vladimir_ether_address,
interface_signature=his_target._interface_signature,
is_me=False)
# Vladimir can substantiate the stamp using his own ether address...
vladimir.substantiate_stamp()
vladimir.stamp_is_valid()
# ...however, the signature for the interface info isn't valid.
with pytest.raises(vladimir.InvalidNode):
vladimir.interface_is_valid()
# Consequently, the metadata isn't valid.
with pytest.raises(vladimir.InvalidNode):
vladimir.validate_metadata()