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 logic for skipping signature validation on old blocks.
6 7 Test logic for skipping signature validation on blocks which we've assumed
8 valid (https://github.com/bitcoin/bitcoin/pull/9484)
9 10 We build a chain that includes an invalid signature for one of the transactions:
11 12 0: genesis block
13 1: block 1 with coinbase transaction output.
14 2-101: bury that block with 100 blocks so the coinbase transaction
15 output can be spent
16 102: a block containing a transaction spending the coinbase
17 transaction output. The transaction has an invalid signature.
18 103-2202: bury the bad block with just over two weeks' worth of blocks
19 (2100 blocks)
20 21 Start a few nodes:
22 23 - node0 has no -assumevalid parameter. Try to sync to block 2202. It will
24 reject block 102 and only sync as far as block 101
25 - node1 has -assumevalid set to the hash of block 102. Try to sync to
26 block 2202. node1 will sync all the way to block 2202.
27 - node2 has -assumevalid set to the hash of block 102. Try to sync to
28 block 200. node2 will reject block 102 since it's assumed valid, but it
29 isn't buried by at least two weeks' work.
30 - node3 has -assumevalid set to the hash of block 102. Feed a longer
31 competing headers-only branch so block #1 is not on the best header chain.
32 - node4 has -assumevalid set to the hash of block 102. Submit an alternative
33 block #1 that is not part of the assumevalid chain.
34 - node5 starts with no -assumevalid parameter. Reindex to hit
35 "assumevalid hash not in headers" and "below minimum chainwork".
36 """
37 38 from test_framework.blocktools import (
39 COINBASE_MATURITY,
40 create_block,
41 create_coinbase,
42 )
43 from test_framework.messages import (
44 CBlockHeader,
45 COutPoint,
46 CTransaction,
47 CTxIn,
48 CTxOut,
49 msg_block,
50 msg_headers,
51 )
52 from test_framework.p2p import P2PInterface
53 from test_framework.script import (
54 CScript,
55 OP_TRUE,
56 )
57 from test_framework.test_framework import BitcoinTestFramework
58 from test_framework.util import assert_equal
59 from test_framework.wallet_util import generate_keypair
60 61 62 class BaseNode(P2PInterface):
63 def send_header_for_blocks(self, new_blocks):
64 headers_message = msg_headers()
65 headers_message.headers = [CBlockHeader(b) for b in new_blocks]
66 self.send_without_ping(headers_message)
67 68 69 class AssumeValidTest(BitcoinTestFramework):
70 def set_test_params(self):
71 self.setup_clean_chain = True
72 self.num_nodes = 6
73 self.rpc_timeout = 120
74 75 def setup_network(self):
76 self.add_nodes(self.num_nodes)
77 # Start node0. We don't start the other nodes yet since
78 # we need to pre-mine a block with an invalid transaction
79 # signature so we can pass in the block hash as assumevalid.
80 self.start_node(0)
81 82 def run_test(self):
83 # Build the blockchain
84 self.tip = int(self.nodes[0].getbestblockhash(), 16)
85 self.block_time = self.nodes[0].getblock(self.nodes[0].getbestblockhash())['time'] + 1
86 87 self.blocks = []
88 89 # Get a pubkey for the coinbase TXO
90 _, coinbase_pubkey = generate_keypair()
91 92 # Create the first block with a coinbase output to our key
93 height = 1
94 block = create_block(self.tip, create_coinbase(height, coinbase_pubkey), ntime=self.block_time)
95 self.blocks.append(block)
96 self.block_time += 1
97 block.solve()
98 # Save the coinbase for later
99 self.block1 = block
100 self.tip = block.hash_int
101 height += 1
102 103 # Bury the block 100 deep so the coinbase output is spendable
104 for _ in range(100):
105 block = create_block(self.tip, height=height, ntime=self.block_time)
106 block.solve()
107 self.blocks.append(block)
108 self.tip = block.hash_int
109 self.block_time += 1
110 height += 1
111 112 # Create a transaction spending the coinbase output with an invalid (null) signature
113 tx = CTransaction()
114 tx.vin.append(CTxIn(COutPoint(self.block1.vtx[0].txid_int, 0), scriptSig=b""))
115 tx.vout.append(CTxOut(49 * 100000000, CScript([OP_TRUE])))
116 117 block102 = create_block(self.tip, height=height, ntime=self.block_time, txlist=[tx])
118 self.block_time += 1
119 block102.solve()
120 self.blocks.append(block102)
121 self.tip = block102.hash_int
122 self.block_time += 1
123 height += 1
124 125 # Bury the assumed valid block 2100 deep
126 for _ in range(2100):
127 block = create_block(self.tip, height=height, ntime=self.block_time)
128 block.solve()
129 self.blocks.append(block)
130 self.tip = block.hash_int
131 self.block_time += 1
132 height += 1
133 block_1_hash = self.blocks[0].hash_hex
134 135 self.start_node(1, extra_args=[f"-assumevalid={block102.hash_hex}"])
136 self.start_node(2, extra_args=[f"-assumevalid={block102.hash_hex}"])
137 self.start_node(3, extra_args=[f"-assumevalid={block102.hash_hex}"])
138 self.start_node(4, extra_args=[f"-assumevalid={block102.hash_hex}"])
139 self.start_node(5)
140 141 # nodes[0]
142 self.log.info("Send blocks to node0. Block 102 will be rejected.")
143 p2p0 = self.nodes[0].add_p2p_connection(BaseNode())
144 p2p0.send_header_for_blocks(self.blocks[0:2000])
145 p2p0.send_header_for_blocks(self.blocks[2000:])
146 with self.nodes[0].assert_debug_log(expected_msgs=[
147 f"Enabling script verification at block #1 ({block_1_hash}): assumevalid=0 (always verify).",
148 ]):
149 p2p0.send_and_ping(msg_block(self.blocks[0]))
150 with self.nodes[0].assert_debug_log(expected_msgs=[
151 "Block validation error: block-script-verify-flag-failed",
152 ]):
153 for i in range(1, 103):
154 p2p0.send_without_ping(msg_block(self.blocks[i]))
155 p2p0.wait_for_disconnect()
156 assert_equal(self.nodes[0].getblockcount(), COINBASE_MATURITY + 1)
157 assert_equal(next(filter(lambda x: x["hash"] == self.blocks[-1].hash_hex, self.nodes[0].getchaintips()))["status"], "invalid")
158 159 # nodes[1]
160 self.log.info("Send all blocks to node1. All blocks will be accepted.")
161 p2p1 = self.nodes[1].add_p2p_connection(BaseNode())
162 p2p1.send_header_for_blocks(self.blocks[0:2000])
163 p2p1.send_header_for_blocks(self.blocks[2000:])
164 with self.nodes[1].assert_debug_log(expected_msgs=[
165 f"Disabling script verification at block #1 ({self.blocks[0].hash_hex}).",
166 ]):
167 p2p1.send_and_ping(msg_block(self.blocks[0]))
168 with self.nodes[1].assert_debug_log(expected_msgs=[
169 f"Enabling script verification at block #103 ({self.blocks[102].hash_hex}): block height above assumevalid height.",
170 ]):
171 for i in range(1, 2202):
172 p2p1.send_without_ping(msg_block(self.blocks[i]))
173 # Syncing 2200 blocks can take a while on slow systems. Give it plenty of time to sync.
174 p2p1.sync_with_ping(timeout=960)
175 assert_equal(self.nodes[1].getblockcount(), 2202)
176 177 # nodes[2]
178 self.log.info("Send blocks to node2. Block 102 will be rejected.")
179 p2p2 = self.nodes[2].add_p2p_connection(BaseNode())
180 p2p2.send_header_for_blocks(self.blocks[0:200])
181 with self.nodes[2].assert_debug_log(expected_msgs=[
182 f"Enabling script verification at block #1 ({block_1_hash}): block too recent relative to best header.",
183 ]):
184 p2p2.send_and_ping(msg_block(self.blocks[0]))
185 with self.nodes[2].assert_debug_log(expected_msgs=[
186 "Block validation error: block-script-verify-flag-failed",
187 ]):
188 for i in range(1, 103):
189 p2p2.send_without_ping(msg_block(self.blocks[i]))
190 p2p2.wait_for_disconnect()
191 assert_equal(self.nodes[2].getblockcount(), COINBASE_MATURITY + 1)
192 assert_equal(next(filter(lambda x: x["hash"] == self.blocks[199].hash_hex, self.nodes[2].getchaintips()))["status"], "invalid")
193 194 # nodes[3]
195 self.log.info("Send two header chains, and a block not in the best header chain to node3.")
196 best_hash = self.nodes[3].getbestblockhash()
197 tip_block = self.nodes[3].getblock(best_hash)
198 second_chain_tip, second_chain_time, second_chain_height = int(best_hash, 16), tip_block["time"] + 1, tip_block["height"] + 1
199 second_chain = []
200 for _ in range(150):
201 block = create_block(second_chain_tip, height=second_chain_height, ntime=second_chain_time)
202 block.solve()
203 second_chain.append(block)
204 second_chain_tip, second_chain_time, second_chain_height = block.hash_int, second_chain_time + 1, second_chain_height + 1
205 p2p3 = self.nodes[3].add_p2p_connection(BaseNode())
206 p2p3.send_header_for_blocks(second_chain)
207 p2p3.send_header_for_blocks(self.blocks[0:103])
208 with self.nodes[3].assert_debug_log(expected_msgs=[
209 f"Enabling script verification at block #1 ({block_1_hash}): block not in best header chain.",
210 ]):
211 p2p3.send_and_ping(msg_block(self.blocks[0]))
212 assert_equal(self.nodes[3].getblockcount(), 1)
213 214 # nodes[4]
215 self.log.info("Send a block not in the assumevalid header chain to node4.")
216 genesis_hash = self.nodes[4].getbestblockhash()
217 genesis_time = self.nodes[4].getblock(genesis_hash)['time']
218 alt1 = create_block(int(genesis_hash, 16), height=1, ntime=genesis_time + 2)
219 alt1.solve()
220 p2p4 = self.nodes[4].add_p2p_connection(BaseNode())
221 p2p4.send_header_for_blocks(self.blocks[0:103])
222 with self.nodes[4].assert_debug_log(expected_msgs=[
223 f"Enabling script verification at block #1 ({alt1.hash_hex}): block not in assumevalid chain.",
224 ]):
225 p2p4.send_and_ping(msg_block(alt1))
226 assert_equal(self.nodes[4].getblockcount(), 1)
227 228 # nodes[5]
229 self.log.info("Reindex to hit specific assumevalid gates (no races with header downloads/chainwork during startup).")
230 p2p5 = self.nodes[5].add_p2p_connection(BaseNode())
231 p2p5.send_header_for_blocks(self.blocks[0:200])
232 p2p5.send_without_ping(msg_block(self.blocks[0]))
233 self.wait_until(lambda: self.nodes[5].getblockcount() == 1)
234 with self.nodes[5].assert_debug_log(expected_msgs=[
235 f"Enabling script verification at block #1 ({block_1_hash}): assumevalid hash not in headers.",
236 ]):
237 self.restart_node(5, extra_args=["-reindex-chainstate", "-assumevalid=1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef"])
238 assert_equal(self.nodes[5].getblockcount(), 1)
239 with self.nodes[5].assert_debug_log(expected_msgs=[
240 f"Enabling script verification at block #1 ({block_1_hash}): best header chainwork below minimumchainwork.",
241 ]):
242 self.restart_node(5, extra_args=["-reindex-chainstate", f"-assumevalid={block102.hash_hex}", "-minimumchainwork=0xffff"])
243 assert_equal(self.nodes[5].getblockcount(), 1)
244 245 246 if __name__ == '__main__':
247 AssumeValidTest(__file__).main()
248