def test_verify_tree(self):
raw_leaves = [secrets.token_bytes(16) for _ in range(16)]
m = MerkleTree(raw_leaves)
tree_nodes = m.nodes[len(m.nodes) // 2:]
tree_hash = m.hash_of_nodes()
self.assertTrue(MerkleTree.verify_tree(tree_nodes, tree_hash))
def test_verify_tree_invalid(self):
raw_leaves = [secrets.token_bytes(16) for _ in range(16)]
m = MerkleTree(raw_leaves)
# Set the last leaf to a random value obviously different then whatever was used to build the tree
# this should cause validation to fail
bad_leaves = m.leaves
bad_leaves[-1] = secrets.token_bytes(16)
self.assertFalse(MerkleTree.verify_tree(bad_leaves, m.root))
def validate_block_contender(self, block: BlockContender) -> bool:
"""
Helper method to validate a block contender. For a block contender to be valid it must:
1) Have a provable merkle tree, ie. all nodes must be hash of (left child + right child)
2) Be signed by at least 2/3 of the top 32 delegates
:param block_contender: The BlockContender to validate
:return: True if the BlockContender is valid, false otherwise
"""
def _validate_sigs(signatures, msg) -> bool:
for sig in signatures:
self.log.info("mn verifying signature: {}".format(sig))
if not sig.verify(msg, sig.sender):
self.log.error(
"!!!! Oh no why couldnt we verify sig {}???".format(
sig))
return False
return True
# Development sanity checks (these should be removed in production)
assert len(
block.nodes
) >= 1, "Masternode got block contender with no nodes! {}".format(
block)
assert len(block.signatures) >= Constants.Testnet.Majority, \
"Received a block contender with only {} signatures (which is less than a majority of {}"\
.format(len(block.signatures), Constants.Testnet.Majority)
# TODO -- ensure that this block contender's previous block is this Masternode's current block...
# Prove Merkle Tree
hash_of_nodes = MerkleTree.hash_nodes(block.nodes)
tx_hashes = block.nodes[len(block.nodes) // 2:]
if not MerkleTree.verify_tree(tx_hashes, hash_of_nodes):
self.log.error(
"\n\n\n\nCOULD NOT VERIFY MERKLE TREE FOR BLOCK CONTENDER {}\n\n\n"
.format(block))
return False
# Validate signatures
if not _validate_sigs(block.signatures, hash_of_nodes):
self.log.error(
"MN COULD NOT VALIDATE SIGNATURES FOR CONTENDER {}".format(
block))
return False
return True
def test_verify_tree(self):
raw_leaves = [secrets.token_bytes(16) for _ in range(16)]
m = MerkleTree(raw_leaves)
self.assertTrue(MerkleTree.verify_tree(m.leaves, m.root))
