Merge pull request #2458 from patricklodder/1.14.4-disconnect-bad-nod…

…e-test

Test that peers building on invalid blocks get disconnected

qa/rpc-tests/p2p-acceptblock.py

@@ -7,7 +7,7 @@
 from test_framework.test_framework import BitcoinTestFramework
 from test_framework.util import *
 import time
-from test_framework.blocktools import create_block, create_coinbase
+from test_framework.blocktools import create_block, create_coinbase, create_transaction
 
 '''
 AcceptBlockTest -- test processing of unrequested blocks.
@@ -54,18 +54,27 @@
 
 7. Send Node0 the missing block again.
    Node0 should process and the tip should advance.
+
+8. Create a fork which is invalid at a height longer than the current chain
+   (ie to which the node will try to reorg) but which has headers built on top
+   of the invalid block. Check that we get disconnected if we send more headers
+   on the chain the node now knows to be invalid.
+
+9. Test Node1 is able to sync when connected to node0 (which should have sufficient
+   work on its chain).
 '''
 
 # TestNode: bare-bones "peer".  Used mostly as a conduit for a test to sending
 # p2p messages to a node, generating the messages in the main testing logic.
 class TestNode(NodeConnCB):
-    def __init__(self):
+    def __init__(self, timeout_factor=1):
         NodeConnCB.__init__(self)
         self.connection = None
         self.ping_counter = 1
         self.last_pong = msg_pong()
 
     def add_connection(self, conn):
+        self.has_been_disconnected = False
         self.connection = conn
 
     # Track the last getdata message we receive (used in the test)
@@ -104,6 +113,17 @@ def sync_with_ping(self, timeout=30):
         self.ping_counter += 1
         return received_pong
 
+    # wait for the socket to be in a closed state
+    def wait_for_disconnect(self, timeout=60):
+        if self.connection == None:
+            return True
+        sleep_time = 0.05
+        is_closed = self.connection.state == "closed"
+        while not is_closed and timeout > 0:
+            time.sleep(sleep_time)
+            timeout -= sleep_time
+            is_closed = self.connection.state == "closed"
+        return is_closed
 
 class AcceptBlockTest(BitcoinTestFramework):
     def add_options(self, parser):
@@ -271,8 +291,82 @@ def run_test(self):
 
         test_node.sync_with_ping()
         assert_equal(self.nodes[0].getblockcount(), 1442)
+        self.nodes[0].getblock(all_blocks[1438].hash)
+        assert_equal(self.nodes[0].getbestblockhash(), all_blocks[1438].hash)
+        assert_raises_jsonrpc(-1, "Block not found on disk", self.nodes[0].getblock, all_blocks[1439].hash)
         print("Successfully reorged to longer chain from non-whitelisted peer")
 
+        # 8. Create a chain which is invalid at a height longer than the
+        # current chain, but which has more blocks on top of that
+        block_1441f = create_block(all_blocks[1436].sha256, create_coinbase(1441), all_blocks[1436].nTime+1)
+        block_1441f.solve()
+        block_1442f = create_block(block_1441f.sha256, create_coinbase(1440), block_1441f.nTime+1)
+        block_1442f.solve()
+        block_1443 = create_block(block_1442f.sha256, create_coinbase(1441), block_1442f.nTime+1)
+        # block_1443 spends a coinbase below maturity!
+        block_1443.vtx.append(create_transaction(block_1442f.vtx[0], 0, b"42", 1))
+        block_1443.hashMerkleRoot = block_1443.calc_merkle_root()
+        block_1443.solve()
+        block_1444 = create_block(block_1443.sha256, create_coinbase(1444), block_1443.nTime+1)
+        block_1444.solve()
+
+        # Now send all the headers on the chain and enough blocks to trigger reorg
+        headers_message = msg_headers()
+        headers_message.headers.append(CBlockHeader(block_1441f))
+        headers_message.headers.append(CBlockHeader(block_1442f))
+        headers_message.headers.append(CBlockHeader(block_1443))
+        headers_message.headers.append(CBlockHeader(block_1444))
+        test_node.send_message(headers_message)
+
+        test_node.sync_with_ping()
+        tip_entry_found = False
+        for x in self.nodes[0].getchaintips():
+            if x['hash'] == block_1444.hash:
+                assert_equal(x['status'], "headers-only")
+                tip_entry_found = True
+        assert(tip_entry_found)
+        assert_raises_jsonrpc(-1, "Block not found on disk", self.nodes[0].getblock, block_1444.hash)
+
+        test_node.send_message(msg_block(block_1441f))
+        test_node.send_message(msg_block(block_1442f))
+
+        test_node.sync_with_ping()
+        self.nodes[0].getblock(block_1441f.hash)
+        self.nodes[0].getblock(block_1442f.hash)
+
+        test_node.send_message(msg_block(block_1443))
+
+        # At this point we've sent an obviously-bogus block,
+        # and we must get disconnected
+        assert_equal(test_node.wait_for_disconnect(), True)
+        print("Successfully got disconnected after sending an invalid block")
+
+        # recreate our malicious node
+        test_node = TestNode()   # connects to node (not whitelisted)
+        connections[0] = NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_node)
+        test_node.add_connection(connections[0])
+        test_node.wait_for_verack()
+
+        # We should have failed reorg and switched back to 1442 (but have block 1443)
+        assert_equal(self.nodes[0].getblockcount(), 1442)
+        assert_equal(self.nodes[0].getbestblockhash(), all_blocks[1438].hash)
+        assert_equal(self.nodes[0].getblock(block_1443.hash)["confirmations"], -1)
+
+        # Now send a new header on the invalid chain, indicating we're forked
+        # off, and expect to get disconnected
+        block_1445 = create_block(block_1444.sha256, create_coinbase(1445), block_1444.nTime+1)
+        block_1445.solve()
+        headers_message = msg_headers()
+        headers_message.headers.append(CBlockHeader(block_1445))
+        test_node.send_message(headers_message)
+        assert_equal(test_node.wait_for_disconnect(), True)
+        print("Successfully got disconnected after building on an invalid block")
+
+        # 9. Connect node1 to node0 and ensure it is able to sync
+        connect_nodes(self.nodes[0], 1)
+        sync_blocks([self.nodes[0], self.nodes[1]])
+        print("Successfully synced nodes 1 and 0")
+
         [ c.disconnect_node() for c in connections ]
 
 if __name__ == '__main__':

qa/rpc-tests/test_framework/mininode.py

@@ -1684,6 +1684,10 @@ def handle_read(self):
             if len(t) > 0:
                 self.recvbuf += t
                 self.got_data()
+            else:
+                self.show_debug_msg("MiniNode: Closing connection to %s:%d after peer disconnect..."
+                                    % (self.dstaddr, self.dstport))
+                self.handle_close()
         except:
             pass