def test_channel_unlock_smaller_locked_amount(
web3,
token_network,
custom_token,
secret_registry_contract,
create_settled_channel,
get_accounts,
reveal_secrets,
):
""" Test an unlock() call that claims too many tokens
When settleChannel() call computes a smaller amount of locked tokens than
the following unlock() call, the settleChannel() computation is stronger and
the participant receives less tokens. Stealing tokens from other channels
is then prevented. """
(A, B) = get_accounts(2)
settle_timeout = 8
# Mock pending transfers data
pending_transfers_tree_A = get_pending_transfers_tree(
web3, [1, 3, 5], [2, 4], settle_timeout)
reveal_secrets(A, pending_transfers_tree_A.unlockable)
unlocked_amount = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree_A.packed_transfers)
# We settle the channel with a smaller locked amount than we will need for the
# actual merkle tree of pending transfers
channel_identifier = create_settled_channel(
A,
pending_transfers_tree_A.locked_amount - 1,
pending_transfers_tree_A.merkle_root,
B,
0,
EMPTY_LOCKSROOT,
settle_timeout,
)
pre_balance_A = custom_token.functions.balanceOf(A).call()
pre_balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_contract == pending_transfers_tree_A.locked_amount - 1
# This should pass, even though the locked amount in storage is smaller.
# B will receive less tokens.
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call_and_transact()
balance_A = custom_token.functions.balanceOf(A).call()
balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_A == (pre_balance_A +
pending_transfers_tree_A.locked_amount -
unlocked_amount - 1)
assert balance_B == pre_balance_B + unlocked_amount
assert balance_contract == 0
def test_channel_unlock_bigger_locked_amount(
web3,
token_network,
custom_token,
secret_registry_contract,
create_settled_channel,
get_accounts,
reveal_secrets,
):
""" Test an unlock() call that claims too little tokens"
When an unlock() call does not contain enough Merkle tree leaves to claim
the locked amount declared in the settleChannel() call, the difference goes
to the other party.
"""
(A, B) = get_accounts(2)
settle_timeout = 8
# Mock pending transfers data
pending_transfers_tree_A = get_pending_transfers_tree(
web3, [1, 3, 5], [2, 4], settle_timeout)
reveal_secrets(A, pending_transfers_tree_A.unlockable)
unlocked_amount = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree_A.packed_transfers)
# We settle the channel with a bigger locked amount than we will need for the
# actual merkle tree of pending transfers
channel_identifier = create_settled_channel(
A,
pending_transfers_tree_A.locked_amount + 1,
pending_transfers_tree_A.merkle_root,
B,
0,
EMPTY_LOCKSROOT,
settle_timeout,
)
pre_balance_A = custom_token.functions.balanceOf(A).call()
pre_balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_contract == pending_transfers_tree_A.locked_amount + 1
# This should pass, even though the locked amount in storage is bigger. The rest of the
# tokens is sent to A, as tokens corresponding to the locks that could not be unlocked.
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call_and_transact()
balance_A = custom_token.functions.balanceOf(A).call()
balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_A == (pre_balance_A +
pending_transfers_tree_A.locked_amount -
unlocked_amount + 1)
assert balance_B == pre_balance_B + unlocked_amount
assert balance_contract == 0
def test_channel_unlock_bigger_unlocked_amount(
web3,
token_network,
custom_token,
secret_registry_contract,
create_settled_channel,
get_accounts,
reveal_secrets,
):
""" unlock() transfers not more than the locked amount for more expensive unlock() demands """
(A, B) = get_accounts(2)
settle_timeout = 8
# Mock pending transfers data
pending_transfers_tree_A = get_pending_transfers_tree(
web3, [1, 3, 5], [2, 4], settle_timeout)
reveal_secrets(A, pending_transfers_tree_A.unlockable)
unlocked_amount = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree_A.packed_transfers)
assert unlocked_amount < pending_transfers_tree_A.locked_amount
# We settle the channel with a smaller locked amount than the amount that can be unlocked
channel_identifier = create_settled_channel(
A,
unlocked_amount - 1,
pending_transfers_tree_A.merkle_root,
B,
0,
EMPTY_LOCKSROOT,
settle_timeout,
)
pre_balance_A = custom_token.functions.balanceOf(A).call()
pre_balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_contract == unlocked_amount - 1
# This should pass, even though the locked amount in storage is smaller.
# B will receive the entire locked amount, corresponding to the locks that have been unlocked
# and A will receive nothing.
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call_and_transact()
balance_A = custom_token.functions.balanceOf(A).call()
balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
assert balance_A == pre_balance_A
assert balance_B == pre_balance_B + unlocked_amount - 1
assert balance_contract == 0
def test_channel_unlock_both_participants(
web3,
custom_token,
token_network,
secret_registry_contract,
create_channel,
channel_deposit,
get_accounts,
close_and_update_channel,
reveal_secrets,
):
""" A scenario where both parties get some of the pending transfers """
(A, B) = get_accounts(2)
settle_timeout = 8
values_A = ChannelValues(deposit=100, transferred=5)
values_B = ChannelValues(deposit=100, transferred=40)
# Create channel and deposit
channel_identifier = create_channel(A, B, settle_timeout)[0]
channel_deposit(channel_identifier, A, values_A.deposit, B)
channel_deposit(channel_identifier, B, values_B.deposit, A)
# Mock pending transfers data for A
pending_transfers_tree_A = get_pending_transfers_tree(
web3, [1, 3, 5], [2, 4], settle_timeout)
values_A.locksroot = pending_transfers_tree_A.merkle_root
values_A.locked_amounts = LockedAmounts(
claimable_locked=get_locked_amount(pending_transfers_tree_A.transfers))
# Reveal A's secrets before settlement window ends
reveal_secrets(A, pending_transfers_tree_A.unlockable)
# Mock pending transfers data for B
pending_transfers_tree_B = get_pending_transfers_tree(
web3, [2, 4, 6], [5, 10], settle_timeout)
values_B.locksroot = pending_transfers_tree_B.merkle_root
values_B.locked_amounts = LockedAmounts(
claimable_locked=get_locked_amount(pending_transfers_tree_B.transfers))
# Reveal B's secrets before settlement window ends
reveal_secrets(B, pending_transfers_tree_B.unlockable)
close_and_update_channel(channel_identifier, A, values_A, B, values_B)
# Settle channel
web3.testing.mine(settle_timeout)
call_settle(token_network, channel_identifier, A, values_A, B, values_B)
pre_balance_A = custom_token.functions.balanceOf(A).call()
pre_balance_B = custom_token.functions.balanceOf(B).call()
pre_balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
# A unlock's
token_network.functions.unlock(
channel_identifier, A, B,
pending_transfers_tree_B.packed_transfers).call_and_transact()
# B unlock's
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call_and_transact()
balance_A = custom_token.functions.balanceOf(A).call()
balance_B = custom_token.functions.balanceOf(B).call()
balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
# Unlocked pending transfers A -> B, that belong to B
unlockable_A = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree_A.packed_transfers)
# Expired pending transfers A -> B, that belong to A
expired_A = get_locked_amount(pending_transfers_tree_A.expired)
# Unlocked pending transfers B -> A, that belong to A
unlockable_B = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree_B.packed_transfers)
# Expired pending transfers B -> A, that belong to B
expired_B = get_locked_amount(pending_transfers_tree_B.expired)
# check that A and B both received the expected amounts
assert balance_contract == (pre_balance_contract -
values_B.locked_amounts.locked -
values_A.locked_amounts.locked)
assert balance_A == pre_balance_A + unlockable_B + expired_A
assert balance_B == pre_balance_B + unlockable_A + expired_B
def test_unlock_channel_event(
web3,
token_network,
secret_registry_contract,
create_channel,
channel_deposit,
get_accounts,
close_and_update_channel,
reveal_secrets,
event_handler,
):
""" Successful unlock() should cause an UNLOCKED event """
(A, B) = get_accounts(2)
settle_timeout = 8
values_A = ChannelValues(deposit=20, transferred=5)
values_B = ChannelValues(deposit=30, transferred=40)
# Create channel and deposit
channel_identifier = create_channel(A, B, settle_timeout)[0]
channel_deposit(channel_identifier, A, values_A.deposit, B)
channel_deposit(channel_identifier, B, values_B.deposit, A)
# Mock pending transfers data
pending_transfers_tree = get_pending_transfers_tree(
web3, [1, 3, 5], [2, 4], settle_timeout + 100)
values_B.locksroot = pending_transfers_tree.merkle_root
values_B.locked_amounts = LockedAmounts(
claimable_locked=get_locked_amount(pending_transfers_tree.transfers))
# Reveal secrets before settlement window ends
reveal_secrets(A, pending_transfers_tree.unlockable)
close_and_update_channel(channel_identifier, A, values_A, B, values_B)
# Settlement window must be over before settling the channel
web3.testing.mine(settle_timeout)
call_settle(token_network, channel_identifier, A, values_A, B, values_B)
ev_handler = event_handler(token_network)
# Unlock the tokens
txn_hash = token_network.functions.unlock(
channel_identifier, A, B,
pending_transfers_tree.packed_transfers).call_and_transact()
unlocked_amount = get_unlocked_amount(
secret_registry_contract, pending_transfers_tree.packed_transfers)
# Add event
ev_handler.add(
txn_hash,
ChannelEvent.UNLOCKED,
check_channel_unlocked(
channel_identifier,
A,
B,
values_B.locksroot,
unlocked_amount,
values_B.locked_amounts.locked - unlocked_amount,
),
)
# Check that event was properly emitted
ev_handler.check()
def f(participants, channel_values, expected_final_balance_A0,
expected_final_balance_B0):
(A, B) = participants
(vals_A, vals_B, balance_proof_type) = channel_values
assert were_balance_proofs_valid(vals_A, vals_B)
# Start channel lifecycle
channel_identifier = create_channel_and_deposit(
A, B, vals_A.deposit, vals_B.deposit)
withdraw_channel(channel_identifier, A, vals_A.withdrawn, B)
withdraw_channel(channel_identifier, B, vals_B.withdrawn, A)
# For the purpose of this test, it is not important when the secrets are revealed,
# as long as the secrets connected to pending transfers that should be finalized,
# are revealed before their expiration.
# Mock pending transfers data for A -> B
pending_transfers_tree_A = get_pending_transfers_tree(
web3,
unlockable_amount=vals_A.locked_amounts.claimable_locked,
expired_amount=vals_A.locked_amounts.unclaimable_locked,
)
vals_A.locksroot = pending_transfers_tree_A.merkle_root
# Reveal A's secrets.
reveal_secrets(A, pending_transfers_tree_A.unlockable)
# Mock pending transfers data for B -> A
pending_transfers_tree_B = get_pending_transfers_tree(
web3,
unlockable_amount=vals_B.locked_amounts.claimable_locked,
expired_amount=vals_B.locked_amounts.unclaimable_locked,
)
vals_B.locksroot = pending_transfers_tree_B.merkle_root
# Reveal B's secrets
reveal_secrets(B, pending_transfers_tree_B.unlockable)
close_and_update_channel(channel_identifier, A, vals_A, B, vals_B)
web3.testing.mine(TEST_SETTLE_TIMEOUT_MIN)
pre_balance_A = custom_token.functions.balanceOf(A).call()
pre_balance_B = custom_token.functions.balanceOf(B).call()
pre_balance_contract = custom_token.functions.balanceOf(
token_network.address).call()
call_settle(token_network, channel_identifier, A, vals_A, B, vals_B)
# We do the balance & state tests here for each channel and also compare with
# the expected settlement amounts
settle_state_tests(
channel_identifier,
A,
vals_A,
B,
vals_B,
pre_balance_A,
pre_balance_B,
pre_balance_contract,
)
# We compute again the settlement amounts here to compare with the other channel
# settlement test values, which should be equal
# Calculate how much A and B should receive
settlement_equivalent = get_settlement_amounts(vals_A, vals_B)
# Calculate how much A and B receive according to onchain computation
settlement_onchain_equivalent = get_onchain_settlement_amounts(
vals_A, vals_B)
assert (settlement_equivalent.participant1_balance ==
settlement_onchain_equivalent.participant1_balance)
assert (settlement_equivalent.participant2_balance ==
settlement_onchain_equivalent.participant2_balance)
assert (settlement_equivalent.participant1_locked ==
settlement_onchain_equivalent.participant1_locked)
assert (settlement_equivalent.participant2_locked ==
settlement_onchain_equivalent.participant2_locked)
assert (get_unlocked_amount(secret_registry_contract,
pending_transfers_tree_B.packed_transfers)
== vals_B.locked_amounts.claimable_locked)
# A unlocks B's pending transfers
info_B = token_network.functions.getChannelParticipantInfo(
channel_identifier, B, A).call()
assert (settlement_equivalent.participant2_locked == info_B[
ParticipantInfoIndex.LOCKED_AMOUNT])
if info_B[ParticipantInfoIndex.LOCKED_AMOUNT] == 0:
with pytest.raises(TransactionFailed):
token_network.functions.unlock(
channel_identifier, A, B,
pending_transfers_tree_B.packed_transfers).call()
else:
token_network.functions.unlock(
channel_identifier, A, B,
pending_transfers_tree_B.packed_transfers).call_and_transact()
# The locked amount should have been removed from contract storage
info_B = token_network.functions.getChannelParticipantInfo(
channel_identifier, B, A).call()
assert info_B[ParticipantInfoIndex.LOCKED_AMOUNT] == 0
assert info_B[ParticipantInfoIndex.LOCKSROOT] == EMPTY_LOCKSROOT
# B unlocks A's pending transfers
info_A = token_network.functions.getChannelParticipantInfo(
channel_identifier, A, B).call()
assert (settlement_equivalent.participant1_locked == info_A[
ParticipantInfoIndex.LOCKED_AMOUNT])
if info_A[ParticipantInfoIndex.LOCKED_AMOUNT] == 0:
with pytest.raises(TransactionFailed):
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call()
else:
token_network.functions.unlock(
channel_identifier, B, A,
pending_transfers_tree_A.packed_transfers).call_and_transact()
# The locked amount should have been removed from contract storage
info_A = token_network.functions.getChannelParticipantInfo(
channel_identifier, A, B).call()
assert info_A[ParticipantInfoIndex.LOCKED_AMOUNT] == 0
assert info_A[ParticipantInfoIndex.LOCKSROOT] == EMPTY_LOCKSROOT
# Do the post settlement and unlock tests for valid balance proofs
balance_A = custom_token.functions.balanceOf(A).call()
balance_B = custom_token.functions.balanceOf(B).call()
# We MUST ensure balance correctness for valid last balance proofs
if balance_proof_type == "valid":
# Calculate how much A and B should receive after the channel is settled and
# unlock is called by both.
(
expected_final_balance_A,
expected_final_balance_B,
) = get_expected_after_settlement_unlock_amounts(vals_A, vals_B)
expected_balance_A = pre_balance_A + expected_final_balance_A
expected_balance_B = pre_balance_B + expected_final_balance_B
assert balance_A == expected_balance_A
assert balance_B <= expected_balance_B
# For balance proofs where one of them is old, we need to compare with the expected
# final balances for the valid last balance proofs
expected_balance_A = pre_balance_A + expected_final_balance_A0
expected_balance_B = pre_balance_B + expected_final_balance_B0
# Tests for when B has submitted an old balance proof for A
# A must not receive less tokens than expected with a valid last balance proof
# B must not receive more tokens than expected with a valid last balance proof
if balance_proof_type == "old_last":
assert balance_A >= expected_balance_A
assert balance_B <= expected_balance_B
# Tests for when A has submitted an old balance proof for B
# A must not receive more tokens than expected with a valid last balance proof
# B must not receive less tokens than expected with a valid last balance proof
if balance_proof_type == "last_old":
assert balance_A <= expected_balance_A
assert balance_B >= expected_balance_B
# Regardless of the tokens received by the two participants, we must make sure tokens
# are not stolen from the other channels. And we must make sure tokens are not locked in
# the contract after the entire channel cycle is finalized.
final_contract_balance = custom_token.functions.balanceOf(
token_network.address).call()
assert final_contract_balance == pre_balance_contract - get_total_available_deposit(
vals_A, vals_B)
assert custom_token.functions.balanceOf(
token_network.address).call() == (
pre_balance_contract -
(expected_final_balance_A0 + expected_final_balance_B0))
