def test_block_parsing_and_serialization(self):
tx_in = TxIn(
prev_tx=b'\x00' * 32,
prev_index=0xffffffff,
script_sig=Script([b'muhhh coinz']),
)
sk = create_sk(100)
sec = sk.verifying_key.to_sec(compressed=False)
tx_out = TxOut(
amount=50 * 100_000_000,
script_pubkey=p2pk_script(sec),
)
coinbase = Tx(
version=1,
tx_ins=[tx_in],
tx_outs=[tx_out],
locktime=0,
)
block = mine(
Block(version=1,
prev_block=genesis.hash(),
merkle_root=merkle_root([coinbase.hash()]),
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[coinbase]))
assert Block.parse(BytesIO(block.serialize())).hash() == block.hash()
def insufficient_proof(bitcoin_node):
block = Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([b'xyz']), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[prepare_coinbase(bob_sec)])
assert not block.check_pow()
valid = False
hints = make_hints([
f'Proof-of-Work not satisfied',
])
return block, valid, hints
def spend_nonexistant_output(bitcoin_node):
coinbase = prepare_coinbase(bob_sec)
tx_in = TxIn(
prev_tx=urandom(32),
prev_index=0,
script_sig=p2pk_script(bob_sec),
)
tx_out = TxOut(
amount=50 * 100_000_000,
script_pubkey=p2pk_script(bob_sec),
)
bad_spend = Tx(
version=1,
tx_ins=[tx_in],
tx_outs=[tx_out],
locktime=0,
)
block = mine(
Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([coinbase.hash(),
bad_spend.hash()]), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[coinbase, bad_spend],
))
valid = False
hints = make_hints([
'this transaction spends an output that does not exist',
])
# FIXME: check that utxo_set was updated
return block, valid, hints
def bad_coinbase(bitcoin_node):
# this scenario sucks b/c we test multiple things and it's unclear whether the latter
# checks are even happening
tx_in = TxIn(
prev_tx=b'\x00' * 32,
prev_index=0xffffffff,
script_sig=p2pk_script(urandom(10)),
)
tx_out = TxOut(
amount=100 * 100_000_000,
script_pubkey=p2pk_script(bob_sec),
)
coinbase = Tx(
version=1,
tx_ins=[tx_in],
tx_outs=[tx_out],
locktime=0,
)
block = mine(
Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([coinbase.hash()]), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[coinbase]))
valid = False
hints = make_hints([
"Bad coinbase",
])
return block, valid, hints
def wrong_bits(bitcoin_node):
block = mine(
Block(version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([b'xyz']),
timestamp=int(time.time()),
bits=target_to_bits(16**63),
nonce=b'\x00\x00\x00\x00',
txns=[prepare_coinbase(bob_sec)]))
valid = False
hints = make_hints([
f'Block.bits should be {repr(starting_bits)}',
])
return block, valid, hints
def missing_coinbase(bitcoin_node):
block = mine(
Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([b'xyz']), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[]))
valid = False
hints = make_hints([
"Look block.txns",
"Coinbase is missing",
])
return block, valid, hints
def good_coinbase(bitcoin_node):
coinbase = prepare_coinbase(bob_sec)
block = mine(
Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([coinbase.hash()]), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[coinbase]))
valid = True
hints = make_hints([
'We need to update the utxo set',
])
# FIXME: check that utxo_set was updated
return block, valid, hints
def first_valid_spend(bitcoin_node):
coinbase = prepare_coinbase(bob_sec)
assert len(list(bitcoin_node.utxo_set.keys())) == 1
outpoint = list(bitcoin_node.utxo_set.keys())[0] # FIXME
utxo = bitcoin_node.utxo_set[outpoint]
tx_in = TxIn(
prev_tx=bytes.fromhex(outpoint[0]),
prev_index=outpoint[1],
)
tx_out = TxOut(
amount=utxo.amount - 10,
script_pubkey=p2pk_script(bob_sec),
)
bad_spend = Tx(
version=1,
tx_ins=[tx_in],
tx_outs=[tx_out],
locktime=0,
)
### HACKS!!! ###
for i in range(len(bad_spend.tx_ins)):
bad_spend.sign_input(i, bob_sk, utxo.script_pubkey)
### /HACKS!!! ###
block = mine(
Block(
version=1,
prev_block=bitcoin_node.headers[-1].hash(),
merkle_root=merkle_root([coinbase.hash(),
bad_spend.hash()]), # FIXME
timestamp=int(time.time()),
bits=starting_bits,
nonce=b'\x00\x00\x00\x00',
txns=[coinbase, bad_spend],
))
valid = True
hints = make_hints([
'did utxo set update?',
])
# FIXME: check that utxo_set was updated
return block, valid, hints
def parse(cls, stream):
block = Block.parse(stream)
return cls(block)
def parse(cls, stream):
return Block.parse(stream)
from io import BytesIO
from solutions.network import PeerConnection, GetHeadersMessage, HeadersMessage, GetDataMessage, BlockMessage
from solutions.block import RAW_GENESIS_BLOCK, BlockHeader, Block
from lib import target_to_bits
GENESIS_HEADER = BlockHeader.parse(BytesIO(RAW_GENESIS_BLOCK))
GENESIS_BLOCK = Block.parse(BytesIO(RAW_GENESIS_BLOCK))
starting_bits = target_to_bits(16**62)
class BitcoinNode:
def __init__(self):
self.headers = [GENESIS_HEADER]
self.blocks = [GENESIS_BLOCK]
self.utxo_set = {}
self.peer = None
def connect(self, host, port):
self.peer = PeerConnection(host, port)
self.peer.handshake()
def receive_header(self, header):
# TODO: verify hash matches
# TODO: check proof-of-work
# append block headers received to headers array
previous = self.headers[-1]
if header.prev_block != previous.hash():
raise RuntimeError('discontinuous block at {}'.format(
len(self.headers)))