def test_get_merkle_root_many(tree_up_to=20):
for number_of_leaves in range(1, tree_up_to): # skipping the empty tree
leaves = [
keccak(str(value).encode()) for value in range(number_of_leaves)
]
merkle_tree = compute_merkle_tree(leaves)
root = get_merkle_root(merkle_tree)
for value in leaves:
proof = compute_merkle_proof(merkle_tree, value)
assert validate_merkle_proof(proof, root, value)
reversed_tree = compute_merkle_tree(reversed(leaves))
assert root == get_merkle_root(reversed_tree)
def test_get_merkle_root_three():
hash_0 = b'a' * 32
hash_1 = b'b' * 32
hash_2 = b'c' * 32
leaves = [hash_0, hash_1, hash_2]
merkle_tree = compute_merkle_tree(leaves)
root = get_merkle_root(merkle_tree)
hash_01 = (b'me\xef\x9c\xa9=5\x16\xa4\xd3\x8a\xb7\xd9\x89\xc2\xb5\x00'
b'\xe2\xfc\x89\xcc\xdc\xf8x\xf9\xc4m\xaa\xf6\xad\r[')
assert keccak(hash_0 + hash_1) == hash_01
calculated_root = keccak(hash_2 + hash_01)
assert root == calculated_root
proof0 = compute_merkle_proof(merkle_tree, hash_0)
proof1 = compute_merkle_proof(merkle_tree, hash_1)
proof2 = compute_merkle_proof(merkle_tree, hash_2)
assert proof0 == [hash_1, hash_2]
assert root == calculated_root
assert validate_merkle_proof(proof0, root, hash_0)
assert proof1 == [hash_0, hash_2]
assert root == calculated_root
assert validate_merkle_proof(proof1, root, hash_1)
# with an odd number of values, the last value wont appear by itself in the
# proof since it isn't hashed with another value
assert proof2 == [keccak(hash_0 + hash_1)]
assert root == calculated_root
assert validate_merkle_proof(proof2, root, hash_2)
def test_get_merkle_root_one():
hash_0 = b'a' * 32
leaves = [hash_0]
merkle_tree = compute_merkle_tree(leaves)
root = get_merkle_root(merkle_tree)
assert root == hash_0
proof = compute_merkle_proof(merkle_tree, hash_0)
assert proof == []
assert root == hash_0
assert validate_merkle_proof(proof, root, hash_0) is True
def test_get_merkle_root_two():
hash_0 = b'a' * 32
hash_1 = b'b' * 32
leaves = [hash_0, hash_1]
merkle_tree = compute_merkle_tree(leaves)
root = get_merkle_root(merkle_tree)
assert root == keccak(hash_0 + hash_1)
proof0 = compute_merkle_proof(merkle_tree, hash_0)
proof1 = compute_merkle_proof(merkle_tree, hash_1)
assert proof0 == [hash_1]
assert root == keccak(hash_0 + hash_1)
assert validate_merkle_proof(proof0, root, hash_0)
assert proof1 == [hash_0]
assert root == keccak(hash_0 + hash_1)
assert validate_merkle_proof(proof1, root, hash_1)
def update_balance(self, balance_proof: BalanceProof, locks: List[Lock]):
""" Update the channel balance with the new balance proof.
This needs to check that the balance proof is valid.
Called by the public interface. """
participant1, participant2 = self.channel_id_to_addresses(
balance_proof.channel_id)
if is_same_address(participant1, balance_proof.sender):
receiver = participant2
elif is_same_address(participant2, balance_proof.sender):
receiver = participant1
else:
raise ValueError(
'Balance proof signature does not match any of the participants.'
)
view1: ChannelView = self.G[balance_proof.sender][receiver]['view']
view2: ChannelView = self.G[receiver][balance_proof.sender]['view']
if view1.transferred_amount >= balance_proof.transferred_amount:
# FIXME: use nonce instead for this check?
raise ValueError('Balance proof is outdated.')
reconstructed_merkle_tree = compute_merkle_tree(lock.compute_hash()
for lock in locks)
reconstructed_merkle_root = get_merkle_root(reconstructed_merkle_tree)
if not reconstructed_merkle_root == balance_proof.locksroot:
raise ValueError(
'Supplied locks do not match the provided locksroot')
view1.update_capacity(
transferred_amount=balance_proof.transferred_amount,
locked_amount=sum(lock.amount_locked for lock in locks))
view2.update_capacity(received_amount=balance_proof.transferred_amount)
def test_compute_merkle_tree_single_entry():
hash_0 = keccak(b'x')
merkle_tree = compute_merkle_tree([hash_0])
assert merkle_tree.layers[-1][0] == hash_0
assert get_merkle_root(merkle_tree) == hash_0
def test_compute_merkle_tree_no_entry():
merkle_tree = compute_merkle_tree([])
assert is_empty_merkle_root(merkle_tree.layers[-1][0])
assert is_empty_merkle_root(get_merkle_root(merkle_tree))
