1 #!/usr/bin/env python3
2 # Copyright (c) 2014-present The Bitcoin Core developers
3 # Distributed under the MIT software license, see the accompanying
4 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 """Test mempool re-org scenarios.
6 7 Test re-org scenarios with a mempool that contains transactions
8 that spend (directly or indirectly) coinbase transactions.
9 """
10 11 import time
12 13 from test_framework.messages import (
14 CInv,
15 MSG_WTX,
16 msg_getdata,
17 )
18 from test_framework.p2p import (
19 P2PTxInvStore,
20 p2p_lock,
21 )
22 from test_framework.test_framework import BitcoinTestFramework
23 from test_framework.util import assert_equal, assert_raises_rpc_error
24 from test_framework.wallet import MiniWallet
25 from test_framework.blocktools import (
26 create_empty_fork,
27 )
28 29 # Number of blocks to create in temporary blockchain branch for reorg testing
30 # needs to be long enough to allow MTP to move arbitrarily forward
31 FORK_LENGTH = 20
32 33 class MempoolCoinbaseTest(BitcoinTestFramework):
34 def set_test_params(self):
35 self.num_nodes = 2
36 self.extra_args = [
37 [
38 '-whitelist=noban@127.0.0.1', # immediate tx relay
39 ],
40 []
41 ]
42 43 def trigger_reorg(self, fork_blocks, node):
44 """Trigger reorg of the fork blocks."""
45 for block in fork_blocks:
46 node.submitblock(block.serialize().hex())
47 assert_equal(self.nodes[0].getbestblockhash(), fork_blocks[-1].hash_hex)
48 49 def test_reorg_relay(self):
50 self.log.info("Test that transactions from disconnected blocks are available for relay immediately")
51 # Prevent time from moving forward
52 self.nodes[1].setmocktime(int(time.time()))
53 self.connect_nodes(0, 1)
54 self.generate(self.wallet, 3)
55 56 # Disconnect node0 and node1 to create different chains.
57 self.disconnect_nodes(0, 1)
58 # Connect a peer to node1, which doesn't have immediate tx relay
59 peer1 = self.nodes[1].add_p2p_connection(P2PTxInvStore())
60 61 # Create a transaction that is included in a block.
62 tx_disconnected = self.wallet.send_self_transfer(from_node=self.nodes[1])
63 self.generate(self.nodes[1], 1, sync_fun=self.no_op)
64 65 # Create a transaction and submit it to node1's mempool.
66 tx_before_reorg = self.wallet.send_self_transfer(from_node=self.nodes[1])
67 68 # Create a child of that transaction and submit it to node1's mempool.
69 tx_child = self.wallet.send_self_transfer(utxo_to_spend=tx_disconnected["new_utxo"], from_node=self.nodes[1])
70 assert_equal(self.nodes[1].getmempoolentry(tx_child["txid"])["ancestorcount"], 1)
71 assert_equal(len(peer1.get_invs()), 0)
72 73 # node0 has a longer chain in which tx_disconnected was not confirmed.
74 self.generate(self.nodes[0], 3, sync_fun=self.no_op)
75 76 # Reconnect the nodes and sync chains. node0's chain should win.
77 self.connect_nodes(0, 1)
78 self.sync_blocks()
79 80 # Child now has an ancestor from the disconnected block
81 assert_equal(self.nodes[1].getmempoolentry(tx_child["txid"])["ancestorcount"], 2)
82 assert_equal(self.nodes[1].getmempoolentry(tx_before_reorg["txid"])["ancestorcount"], 1)
83 84 # peer1 should not have received an inv for any of the transactions during this time, as no
85 # mocktime has elapsed for those transactions to be announced. Likewise, it cannot
86 # request very recent, unanounced transactions.
87 assert_equal(len(peer1.get_invs()), 0)
88 # It's too early to request these two transactions
89 requests_too_recent = msg_getdata([CInv(t=MSG_WTX, h=tx["tx"].wtxid_int) for tx in [tx_before_reorg, tx_child]])
90 peer1.send_and_ping(requests_too_recent)
91 for _ in range(len(requests_too_recent.inv)):
92 peer1.sync_with_ping()
93 with p2p_lock:
94 assert "tx" not in peer1.last_message
95 assert "notfound" in peer1.last_message
96 97 # Request the tx from the disconnected block
98 request_disconnected_tx = msg_getdata([CInv(t=MSG_WTX, h=tx_disconnected["tx"].wtxid_int)])
99 peer1.send_and_ping(request_disconnected_tx)
100 101 # The tx from the disconnected block was never announced, and it entered the mempool later
102 # than the transactions that are too recent.
103 assert_equal(len(peer1.get_invs()), 0)
104 with p2p_lock:
105 # However, the node will answer requests for the tx from the recently-disconnected block.
106 assert_equal(peer1.last_message["tx"].tx.wtxid_hex,tx_disconnected["tx"].wtxid_hex)
107 108 self.nodes[1].setmocktime(int(time.time()) + 300)
109 peer1.sync_with_ping()
110 # the transactions are now announced
111 assert_equal(len(peer1.get_invs()), 3)
112 for _ in range(3):
113 # make sure all tx requests have been responded to
114 peer1.sync_with_ping()
115 last_tx_received = peer1.last_message["tx"]
116 117 tx_after_reorg = self.wallet.send_self_transfer(from_node=self.nodes[1])
118 request_after_reorg = msg_getdata([CInv(t=MSG_WTX, h=tx_after_reorg["tx"].wtxid_int)])
119 assert tx_after_reorg["txid"] in self.nodes[1].getrawmempool()
120 peer1.send_and_ping(request_after_reorg)
121 with p2p_lock:
122 assert_equal(peer1.last_message["tx"], last_tx_received)
123 124 def run_test(self):
125 self.wallet = MiniWallet(self.nodes[0])
126 wallet = self.wallet
127 128 # Prevent clock from moving blocks further forward in time
129 now = int(time.time())
130 self.nodes[0].setmocktime(now)
131 132 # Start with a 200 block chain
133 assert_equal(self.nodes[0].getblockcount(), 200)
134 135 self.log.info("Add 4 coinbase utxos to the miniwallet")
136 # Block 76 contains the first spendable coinbase txs.
137 first_block = 76
138 139 # Three scenarios for re-orging coinbase spends in the memory pool:
140 # 1. Direct coinbase spend : spend_1
141 # 2. Indirect (coinbase spend in chain, child in mempool) : spend_2 and spend_2_1
142 # 3. Indirect (coinbase and child both in chain) : spend_3 and spend_3_1
143 # Use re-org to make all of the above coinbase spends invalid (immature coinbase),
144 # and make sure the mempool code behaves correctly.
145 b = [self.nodes[0].getblockhash(n) for n in range(first_block, first_block+4)]
146 coinbase_txids = [self.nodes[0].getblock(h)['tx'][0] for h in b]
147 utxo_1 = wallet.get_utxo(txid=coinbase_txids[1])
148 utxo_2 = wallet.get_utxo(txid=coinbase_txids[2])
149 utxo_3 = wallet.get_utxo(txid=coinbase_txids[3])
150 self.log.info("Create three transactions spending from coinbase utxos: spend_1, spend_2, spend_3")
151 spend_1 = wallet.create_self_transfer(utxo_to_spend=utxo_1)
152 spend_2 = wallet.create_self_transfer(utxo_to_spend=utxo_2)
153 spend_3 = wallet.create_self_transfer(utxo_to_spend=utxo_3)
154 155 self.log.info("Create another transaction which is time-locked to 300 seconds in the future")
156 future = now + 300
157 utxo = wallet.get_utxo(txid=coinbase_txids[0])
158 timelock_tx = wallet.create_self_transfer(
159 utxo_to_spend=utxo,
160 locktime=future,
161 )['hex']
162 163 self.log.info("Check that the time-locked transaction is too immature to spend")
164 assert_raises_rpc_error(-26, "non-final", self.nodes[0].sendrawtransaction, timelock_tx)
165 166 self.log.info("Broadcast and mine spend_2 and spend_3")
167 spend_2_id = wallet.sendrawtransaction(from_node=self.nodes[0], tx_hex=spend_2['hex'])
168 wallet.sendrawtransaction(from_node=self.nodes[0], tx_hex=spend_3['hex'])
169 self.log.info("Generate a block")
170 self.generate(self.nodes[0], 1)
171 self.log.info("Check that time-locked transaction is still too immature to spend")
172 assert_raises_rpc_error(-26, 'non-final', self.nodes[0].sendrawtransaction, timelock_tx)
173 174 self.log.info("Create spend_2_1 and spend_3_1")
175 spend_2_1 = wallet.create_self_transfer(utxo_to_spend=spend_2["new_utxo"], version=1)
176 spend_3_1 = wallet.create_self_transfer(utxo_to_spend=spend_3["new_utxo"])
177 178 self.log.info("Broadcast and mine spend_3_1")
179 spend_3_1_id = self.nodes[0].sendrawtransaction(spend_3_1['hex'])
180 self.log.info("Generate a block")
181 182 # Prep for fork, only go FORK_LENGTH seconds into the MTP future max
183 fork_blocks = create_empty_fork(self.nodes[0], fork_length=FORK_LENGTH)
184 185 # Jump node and MTP 300 seconds and generate a slightly weaker chain than reorg one
186 self.nodes[0].setmocktime(future)
187 self.generate(self.nodes[0], FORK_LENGTH - 1)
188 block_time = self.nodes[0].getblock(self.nodes[0].getbestblockhash())['time']
189 assert(block_time >= now + 300)
190 191 # generate() implicitly syncs blocks, so that peer 1 gets the block before timelock_tx
192 # Otherwise, peer 1 would put the timelock_tx in m_lazy_recent_rejects
193 self.log.info("The time-locked transaction can now be spent")
194 timelock_tx_id = self.nodes[0].sendrawtransaction(timelock_tx)
195 196 self.log.info("Add spend_1 and spend_2_1 to the mempool")
197 spend_1_id = self.nodes[0].sendrawtransaction(spend_1['hex'])
198 spend_2_1_id = self.nodes[0].sendrawtransaction(spend_2_1['hex'])
199 200 assert_equal(set(self.nodes[0].getrawmempool()), {spend_1_id, spend_2_1_id, timelock_tx_id})
201 self.sync_all()
202 203 self.trigger_reorg(fork_blocks, self.nodes[0])
204 self.sync_blocks()
205 206 # We went backwards in time to boot timelock_tx_id
207 fork_block_time = self.nodes[0].getblock(self.nodes[0].getbestblockhash())['time']
208 assert fork_block_time < block_time
209 210 self.log.info("The time-locked transaction is now too immature and has been removed from the mempool")
211 self.log.info("spend_3_1 has been re-orged out of the chain and is back in the mempool")
212 assert_equal(set(self.nodes[0].getrawmempool()), {spend_1_id, spend_2_1_id, spend_3_1_id})
213 214 self.log.info("Reorg out enough blocks to get spend_2 back in the mempool, along with its child")
215 216 while (spend_2_id not in self.nodes[0].getrawmempool()):
217 b = self.nodes[0].getbestblockhash()
218 for node in self.nodes:
219 node.invalidateblock(b)
220 221 assert(spend_2_id in self.nodes[0].getrawmempool())
222 assert(spend_2_1_id in self.nodes[0].getrawmempool())
223 224 # Chain 10 more transactions off of spend_2_1
225 self.log.info("Give spend_2 some more descendants by creating a chain of 10 transactions spending from it")
226 parent_utxo = spend_2_1["new_utxo"]
227 for i in range(10):
228 tx = wallet.create_self_transfer(utxo_to_spend=parent_utxo, version=1)
229 self.nodes[0].sendrawtransaction(tx['hex'])
230 parent_utxo = tx["new_utxo"]
231 232 self.log.info("Use invalidateblock to re-org back and make all those coinbase spends immature/invalid")
233 b = self.nodes[0].getblockhash(first_block + 100)
234 235 # Use invalidateblock to go backwards in MTP time.
236 # invalidateblock actually moves MTP backwards, making timelock_tx_id valid again.
237 for node in self.nodes:
238 node.invalidateblock(b)
239 240 self.log.info("Check that the mempool is empty")
241 assert_equal(set(self.nodes[0].getrawmempool()), set())
242 self.sync_all()
243 244 self.test_reorg_relay()
245 246 247 if __name__ == '__main__':
248 MempoolCoinbaseTest(__file__).main()
249