1 #!/usr/bin/env python3
2 # Copyright (c) 2017-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 setting nMinimumChainWork on command line.
6 7 Nodes don't consider themselves out of "initial block download" until
8 their active chain has more work than nMinimumChainWork.
9 10 Nodes don't download blocks from a peer unless the peer's best known block
11 has more work than nMinimumChainWork.
12 13 While in initial block download, nodes won't relay blocks to their peers, so
14 test that this parameter functions as intended by verifying that block relay
15 only succeeds past a given node once its nMinimumChainWork has been exceeded.
16 """
17 18 import time
19 20 from test_framework.p2p import P2PInterface, msg_getheaders
21 from test_framework.test_framework import BitcoinTestFramework
22 from test_framework.util import (
23 assert_equal,
24 ensure_for,
25 assert_not_equal,
26 )
27 28 # 2 hashes required per regtest block (with no difficulty adjustment)
29 REGTEST_WORK_PER_BLOCK = 2
30 31 class MinimumChainWorkTest(BitcoinTestFramework):
32 def set_test_params(self):
33 self.setup_clean_chain = True
34 self.num_nodes = 3
35 36 self.extra_args = [[], ["-minimumchainwork=0x65"], ["-minimumchainwork=0x65"]]
37 self.node_min_work = [0, 101, 101]
38 39 def setup_network(self):
40 # This test relies on the chain setup being:
41 # node0 <- node1 <- node2
42 # Before leaving IBD, nodes prefer to download blocks from outbound
43 # peers, so ensure that we're mining on an outbound peer and testing
44 # block relay to inbound peers.
45 self.setup_nodes()
46 for i in range(self.num_nodes-1):
47 self.connect_nodes(i+1, i)
48 49 # Set clock of node2 2 days ahead, to keep it in IBD during this test.
50 self.nodes[2].setmocktime(int(time.time()) + 48*60*60)
51 52 def run_test(self):
53 # Start building a chain on node0. node2 shouldn't be able to sync until node1's
54 # minchainwork is exceeded
55 starting_chain_work = REGTEST_WORK_PER_BLOCK # Genesis block's work
56 self.log.info(f"Testing relay across node 1 (minChainWork = {self.node_min_work[1]})")
57 58 starting_blockcount = self.nodes[2].getblockcount()
59 60 num_blocks_to_generate = int((self.node_min_work[1] - starting_chain_work) / REGTEST_WORK_PER_BLOCK)
61 self.log.info(f"Generating {num_blocks_to_generate} blocks on node0")
62 hashes = self.generate(self.nodes[0], num_blocks_to_generate, sync_fun=self.no_op)
63 64 self.log.info(f"Node0 current chain work: {self.nodes[0].getblockheader(hashes[-1])['chainwork']}")
65 self.log.info("Verifying node 2 has no more blocks than before")
66 self.log.info(f"Blockcounts: {[n.getblockcount() for n in self.nodes]}")
67 # Node2 shouldn't have any new headers yet, because node1 should not
68 # have relayed anything.
69 # We wait 3 seconds, rather than sync_blocks(node0, node1) because
70 # it's reasonable either way for node1 to get the blocks, or not get
71 # them (since they're below node1's minchainwork).
72 ensure_for(duration=3, f=lambda: len(self.nodes[2].getchaintips()) == 1)
73 assert_equal(self.nodes[2].getchaintips()[0]['height'], 0)
74 75 assert_not_equal(self.nodes[1].getbestblockhash(), self.nodes[0].getbestblockhash())
76 assert_equal(self.nodes[2].getblockcount(), starting_blockcount)
77 78 self.log.info("Check that getheaders requests to node2 are ignored")
79 peer = self.nodes[2].add_p2p_connection(P2PInterface())
80 msg = msg_getheaders()
81 msg.locator.vHave = [int(self.nodes[2].getbestblockhash(), 16)]
82 msg.hashstop = 0
83 peer.send_and_ping(msg)
84 ensure_for(duration=5, f=lambda: "headers" not in peer.last_message or len(peer.last_message["headers"].headers) == 0)
85 86 self.log.info("Generating one more block")
87 self.generate(self.nodes[0], 1)
88 89 self.log.info("Verifying nodes are all synced")
90 91 # Because nodes in regtest are all manual connections (eg using
92 # addnode), node1 should not have disconnected node0. If not for that,
93 # we'd expect node1 to have disconnected node0 for serving an
94 # insufficient work chain, in which case we'd need to reconnect them to
95 # continue the test.
96 97 self.sync_all()
98 self.log.info(f"Blockcounts: {[n.getblockcount() for n in self.nodes]}")
99 100 self.log.info("Test that getheaders requests to node2 are not ignored")
101 peer.send_and_ping(msg)
102 assert "headers" in peer.last_message
103 104 # Verify that node2 is in fact still in IBD (otherwise this test may
105 # not be exercising the logic we want!)
106 assert_equal(self.nodes[2].getblockchaininfo()['initialblockdownload'], True)
107 108 self.log.info("Test -minimumchainwork with a non-hex value")
109 self.stop_node(0)
110 self.nodes[0].assert_start_raises_init_error(
111 ["-minimumchainwork=test"],
112 expected_msg='Error: Invalid minimum work specified (test), must be up to 64 hex digits',
113 )
114 115 116 if __name__ == '__main__':
117 MinimumChainWorkTest(__file__).main()
118