def validate_transaction(self, tx):
if not tx.is_valid():
return False
available_value = 0
spending_value = 0
previous_outputs = []
for tx_in in tx.inputs:
id = tx_in.prevout.hex
tx_out = self.get_utxo(id)
if not tx_out:
return False
previous_outputs.append(tx_out)
available_value += tx_out.value
for tx_out in tx.outputs:
spending_value += tx_out.value
if spending_value > available_value:
return False
for tx_in, tx_out in zip(tx.inputs, previous_outputs):
script = tx_in.unlocking_script + tx_out.locking_script
# script.sighashes = [sighash_all(tx)] # insert tx_out hashes
result = script.execute(memory={0x100: sighash_all(tx)})
if not result:
return False
return True
def test_flow_16():
"""
This MUST NOT fail
"""
blockchain = Blockchain()
coinbase_0 = Tx([TxIn(OutPoint("00" * 32, 0), Script())],
[TxOut(10**10, Script())])
coinbase_0.outputs[0].locking_script = lock_p2pkh(
pubkey_hash_from_prvkey(1))
origin_transactions = [coinbase_0]
origin_header = BlockHeader("00" * 32,
generate_merkle_root(origin_transactions), 0)
origin = Block(origin_header, origin_transactions)
assert blockchain.add_blocks([origin])
coinbase_1 = Tx(
[TxIn(OutPoint("00" * 32, 0), Script())],
[TxOut(5 * 10**9, Script()),
TxOut(5 * 10**9, Script())],
)
tx = Tx(
[TxIn(OutPoint(coinbase_0.txid, 0), Script())],
[TxOut(10**10 - 100, Script()),
TxOut(50, Script())],
)
tx.inputs[0].unlocking_script = unlock_p2pkh(sighash_all(tx), 1)
block_1_transactions = [coinbase_1, tx]
block_1_header = BlockHeader(origin.header.pow,
generate_merkle_root(block_1_transactions), 0)
block_1 = Block(block_1_header, block_1_transactions)
assert blockchain.add_blocks([block_1])
reset_blockchain()