1 #!/usr/bin/env python3
2 # Copyright (c) 2021-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 ThreadDNSAddressSeed logic for querying DNS seeds."""
6 7 import itertools
8 9 from test_framework.netutil import UNREACHABLE_PROXY_ARG
10 from test_framework.p2p import P2PInterface
11 from test_framework.test_framework import BitcoinTestFramework
12 13 14 class P2PDNSSeeds(BitcoinTestFramework):
15 def set_test_params(self):
16 self.setup_clean_chain = True
17 self.num_nodes = 1
18 self.extra_args = [["-dnsseed=1", UNREACHABLE_PROXY_ARG]]
19 20 def run_test(self):
21 self.init_arg_tests()
22 self.existing_outbound_connections_test()
23 self.existing_block_relay_connections_test()
24 self.force_dns_test()
25 self.wait_time_tests()
26 27 def init_arg_tests(self):
28 fakeaddr = "fakenodeaddr.fakedomain.invalid."
29 30 self.log.info("Check that setting -connect disables -dnsseed by default")
31 self.nodes[0].stop_node()
32 with self.nodes[0].assert_debug_log(expected_msgs=["DNS seeding disabled"], timeout=2):
33 self.start_node(0, extra_args=[f"-connect={fakeaddr}", UNREACHABLE_PROXY_ARG])
34 35 self.log.info("Check that running -connect and -dnsseed means DNS logic runs.")
36 with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
37 self.restart_node(0, extra_args=[f"-connect={fakeaddr}", "-dnsseed=1", UNREACHABLE_PROXY_ARG])
38 39 self.log.info("Check that running -forcednsseed and -dnsseed=0 throws an error.")
40 self.nodes[0].stop_node()
41 self.nodes[0].assert_start_raises_init_error(
42 expected_msg="Error: Cannot set -forcednsseed to true when setting -dnsseed to false.",
43 extra_args=["-forcednsseed=1", "-dnsseed=0"],
44 )
45 46 self.log.info("Check that running -forcednsseed and -connect throws an error.")
47 # -connect soft sets -dnsseed to false, so throws the same error
48 self.nodes[0].stop_node()
49 self.nodes[0].assert_start_raises_init_error(
50 expected_msg="Error: Cannot set -forcednsseed to true when setting -dnsseed to false.",
51 extra_args=["-forcednsseed=1", f"-connect={fakeaddr}"],
52 )
53 54 # Restore default bitcoind settings
55 self.restart_node(0)
56 57 def existing_outbound_connections_test(self):
58 # Make sure addrman is populated to enter the conditional where we
59 # delay and potentially skip DNS seeding.
60 self.nodes[0].addpeeraddress("192.0.0.8", 8333)
61 62 self.log.info("Check that we *do not* query DNS seeds if we have 2 outbound connections")
63 64 self.restart_node(0)
65 with self.nodes[0].assert_debug_log(expected_msgs=["P2P peers available. Skipped DNS seeding."], timeout=12):
66 for i in range(2):
67 self.nodes[0].add_outbound_p2p_connection(P2PInterface(), p2p_idx=i, connection_type="outbound-full-relay")
68 69 def existing_block_relay_connections_test(self):
70 # Make sure addrman is populated to enter the conditional where we
71 # delay and potentially skip DNS seeding. No-op when run after
72 # existing_outbound_connections_test.
73 self.nodes[0].addpeeraddress("192.0.0.8", 8333)
74 75 self.log.info("Check that we *do* query DNS seeds if we only have 2 block-relay-only connections")
76 77 self.restart_node(0)
78 with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
79 # This mimics the "anchors" logic where nodes are likely to
80 # reconnect to block-relay-only connections on startup.
81 # Since we do not participate in addr relay with these connections,
82 # we still want to query the DNS seeds.
83 for i in range(2):
84 self.nodes[0].add_outbound_p2p_connection(P2PInterface(), p2p_idx=i, connection_type="block-relay-only")
85 86 def force_dns_test(self):
87 self.log.info("Check that we query DNS seeds if -forcednsseed param is set")
88 89 with self.nodes[0].assert_debug_log(expected_msgs=["Loading addresses from DNS seed"], timeout=12):
90 # -dnsseed defaults to 1 in bitcoind, but 0 in the test framework,
91 # so pass it explicitly here
92 self.restart_node(0, ["-forcednsseed", "-dnsseed=1", UNREACHABLE_PROXY_ARG])
93 94 # Restore default for subsequent tests
95 self.restart_node(0)
96 97 def wait_time_tests(self):
98 self.log.info("Check the delay before querying DNS seeds")
99 100 # Populate addrman with < 1000 addresses
101 for i in range(5):
102 a = f"192.0.0.{i}"
103 self.nodes[0].addpeeraddress(a, 8333)
104 105 # The delay should be 11 seconds
106 with self.nodes[0].assert_debug_log(expected_msgs=["Waiting 11 seconds before querying DNS seeds.\n"], timeout=2):
107 self.restart_node(0)
108 109 # Populate addrman with > 1000 addresses
110 for i in itertools.count():
111 first_octet = i % 2 + 1
112 second_octet = i % 256
113 third_octet = i % 100
114 a = f"{first_octet}.{second_octet}.{third_octet}.1"
115 self.nodes[0].addpeeraddress(a, 8333)
116 if (i > 1000 and i % 100 == 0):
117 # The addrman size is non-deterministic because new addresses
118 # are sorted into buckets, potentially displacing existing
119 # addresses. Periodically check if we have met the desired
120 # threshold.
121 if len(self.nodes[0].getnodeaddresses(0)) > 1000:
122 break
123 124 # The delay should be 5 mins
125 with self.nodes[0].assert_debug_log(expected_msgs=["Waiting 300 seconds before querying DNS seeds.\n"], timeout=2):
126 self.restart_node(0)
127 128 129 if __name__ == '__main__':
130 P2PDNSSeeds(__file__).main()
131