p2p_headers_sync_with_minchainwork.py
1 #!/usr/bin/env python3 2 # Copyright (c) 2019-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 that we reject low difficulty headers to prevent our block tree from filling up with useless bloat""" 6 7 from test_framework.test_framework import BitcoinTestFramework 8 9 from test_framework.p2p import ( 10 P2PInterface, 11 ) 12 13 from test_framework.messages import ( 14 msg_headers, 15 ) 16 17 from test_framework.blocktools import ( 18 NORMAL_GBT_REQUEST_PARAMS, 19 create_block, 20 ) 21 22 from test_framework.util import assert_equal 23 24 import time 25 26 NODE1_BLOCKS_REQUIRED = 15 27 NODE2_BLOCKS_REQUIRED = 2047 28 29 30 class RejectLowDifficultyHeadersTest(BitcoinTestFramework): 31 def set_test_params(self): 32 self.rpc_timeout *= 4 # To avoid timeout when generating BLOCKS_TO_MINE 33 self.setup_clean_chain = True 34 self.num_nodes = 4 35 # Node0 has no required chainwork; node1 requires 15 blocks on top of the genesis block; node2 requires 2047 36 self.extra_args = [["-minimumchainwork=0x0", "-checkblockindex=0"], ["-minimumchainwork=0x1f", "-checkblockindex=0"], ["-minimumchainwork=0x1000", "-checkblockindex=0"], ["-minimumchainwork=0x1000", "-checkblockindex=0", "-whitelist=noban@127.0.0.1"]] 37 38 def setup_network(self): 39 self.setup_nodes() 40 self.reconnect_all() 41 self.sync_all() 42 43 def disconnect_all(self): 44 self.disconnect_nodes(0, 1) 45 self.disconnect_nodes(0, 2) 46 self.disconnect_nodes(0, 3) 47 48 def reconnect_all(self): 49 self.connect_nodes(0, 1) 50 self.connect_nodes(0, 2) 51 self.connect_nodes(0, 3) 52 53 def mocktime_all(self, time): 54 for n in self.nodes: 55 n.setmocktime(time) 56 57 def test_chains_sync_when_long_enough(self): 58 self.log.info("Generate blocks on the node with no required chainwork, and verify nodes 1 and 2 have no new headers in their headers tree") 59 with ( 60 self.nodes[1].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=14)"], timeout=2), 61 self.nodes[2].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=14)"], timeout=2), 62 self.nodes[3].assert_debug_log(expected_msgs=["Synchronizing blockheaders, height: 14"], timeout=2), 63 ): 64 self.generate(self.nodes[0], NODE1_BLOCKS_REQUIRED-1, sync_fun=self.no_op) 65 66 # Node3 should always allow headers due to noban permissions 67 self.log.info("Check that node3 will sync headers (due to noban permissions)") 68 69 def check_node3_chaintips(num_tips, tip_hash, height): 70 node3_chaintips = self.nodes[3].getchaintips() 71 assert_equal(len(node3_chaintips), num_tips) 72 assert { 73 'height': height, 74 'hash': tip_hash, 75 'branchlen': height, 76 'status': 'headers-only', 77 } in node3_chaintips 78 79 check_node3_chaintips(2, self.nodes[0].getbestblockhash(), NODE1_BLOCKS_REQUIRED-1) 80 81 for node in self.nodes[1:3]: 82 chaintips = node.getchaintips() 83 assert_equal(len(chaintips), 1) 84 assert { 85 'height': 0, 86 'hash': '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206', 87 'branchlen': 0, 88 'status': 'active', 89 } in chaintips 90 91 self.log.info("Generate more blocks to satisfy node1's minchainwork requirement, and verify node2 still has no new headers in headers tree") 92 with ( 93 self.nodes[2].assert_debug_log(expected_msgs=["[net] Ignoring low-work chain (height=15)"], timeout=2), 94 self.nodes[3].assert_debug_log(expected_msgs=["Synchronizing blockheaders, height: 15"], timeout=2), 95 ): 96 self.generate(self.nodes[0], NODE1_BLOCKS_REQUIRED - self.nodes[0].getblockcount(), sync_fun=self.no_op) 97 self.sync_blocks(self.nodes[0:2]) # node3 will sync headers (noban permissions) but not blocks (due to minchainwork) 98 99 assert { 100 'height': 0, 101 'hash': '0f9188f13cb7b2c71f2a335e3a4fc328bf5beb436012afca590b1a11466e2206', 102 'branchlen': 0, 103 'status': 'active', 104 } in self.nodes[2].getchaintips() 105 106 assert_equal(len(self.nodes[2].getchaintips()), 1) 107 108 self.log.info("Check that node3 accepted these headers as well") 109 check_node3_chaintips(2, self.nodes[0].getbestblockhash(), NODE1_BLOCKS_REQUIRED) 110 111 self.log.info("Generate long chain for node0/node1/node3") 112 self.generate(self.nodes[0], NODE2_BLOCKS_REQUIRED-self.nodes[0].getblockcount(), sync_fun=self.no_op) 113 114 self.log.info("Verify that node2 and node3 will sync the chain when it gets long enough") 115 self.sync_blocks() 116 117 def test_peerinfo_includes_headers_presync_height(self): 118 self.log.info("Test that getpeerinfo() includes headers presync height") 119 120 # Disconnect network, so that we can find our own peer connection more 121 # easily 122 self.disconnect_all() 123 124 p2p = self.nodes[0].add_p2p_connection(P2PInterface()) 125 node = self.nodes[0] 126 127 # Ensure we have a long chain already 128 current_height = self.nodes[0].getblockcount() 129 if (current_height < 3000): 130 self.generate(node, 3000-current_height, sync_fun=self.no_op) 131 132 # Send a group of 2000 headers, forking from genesis. 133 new_blocks = [] 134 hashPrevBlock = int(node.getblockhash(0), 16) 135 for i in range(2000): 136 block = create_block(hashprev = hashPrevBlock, tmpl=node.getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)) 137 block.solve() 138 new_blocks.append(block) 139 hashPrevBlock = block.hash_int 140 141 headers_message = msg_headers(headers=new_blocks) 142 p2p.send_and_ping(headers_message) 143 144 # getpeerinfo should show a sync in progress 145 assert_equal(node.getpeerinfo()[0]['presynced_headers'], 2000) 146 147 def test_large_reorgs_can_succeed(self): 148 self.log.info("Test that a 2000+ block reorg, starting from a point that is more than 2000 blocks before a locator entry, can succeed") 149 150 self.sync_all() # Ensure all nodes are synced. 151 self.disconnect_all() 152 153 # locator(block at height T) will have heights: 154 # [T, T-1, ..., T-10, T-12, T-16, T-24, T-40, T-72, T-136, T-264, 155 # T-520, T-1032, T-2056, T-4104, ...] 156 # So mine a number of blocks > 4104 to ensure that the first window of 157 # received headers during a sync are fully between locator entries. 158 BLOCKS_TO_MINE = 4110 159 160 self.generate(self.nodes[0], BLOCKS_TO_MINE, sync_fun=self.no_op) 161 self.generate(self.nodes[1], BLOCKS_TO_MINE+2, sync_fun=self.no_op) 162 163 self.reconnect_all() 164 165 self.mocktime_all(int(time.time())) # Temporarily hold time to avoid internal timeouts 166 self.sync_blocks(timeout=300) # Ensure tips eventually agree 167 self.mocktime_all(0) 168 169 170 def run_test(self): 171 self.test_chains_sync_when_long_enough() 172 173 self.test_large_reorgs_can_succeed() 174 175 self.test_peerinfo_includes_headers_presync_height() 176 177 178 179 if __name__ == '__main__': 180 RejectLowDifficultyHeadersTest(__file__).main()