1 files changed, 163 insertions, 0 deletions
diff --git a/test/functional/p2p-versionbits-warning.py b/test/functional/p2p-versionbits-warning.py
new file mode 100755
index 0000000000..dc714e9a4a
--- /dev/null
+++ b/test/functional/p2p-versionbits-warning.py
@@ -0,0 +1,163 @@
+#!/usr/bin/env python3
+# Copyright (c) 2016 The Bitcoin Core developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+"""Test version bits warning system.
+
+Generate chains with block versions that appear to be signalling unknown
+soft-forks, and test that warning alerts are generated.
+"""
+
+from test_framework.mininode import *
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
+import re
+import time
+from test_framework.blocktools import create_block, create_coinbase
+
+VB_PERIOD = 144 # versionbits period length for regtest
+VB_THRESHOLD = 108 # versionbits activation threshold for regtest
+VB_TOP_BITS = 0x20000000
+VB_UNKNOWN_BIT = 27 # Choose a bit unassigned to any deployment
+
+WARN_UNKNOWN_RULES_MINED = "Unknown block versions being mined! It's possible unknown rules are in effect"
+WARN_UNKNOWN_RULES_ACTIVE = "unknown new rules activated (versionbit {})".format(VB_UNKNOWN_BIT)
+VB_PATTERN = re.compile("^Warning.*versionbit")
+
+# 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):
+        NodeConnCB.__init__(self)
+        self.connection = None
+        self.ping_counter = 1
+        self.last_pong = msg_pong()
+
+    def add_connection(self, conn):
+        self.connection = conn
+
+    def on_inv(self, conn, message):
+        pass
+
+    # Wrapper for the NodeConn's send_message function
+    def send_message(self, message):
+        self.connection.send_message(message)
+
+    def on_pong(self, conn, message):
+        self.last_pong = message
+
+    # Sync up with the node after delivery of a block
+    def sync_with_ping(self, timeout=30):
+        self.connection.send_message(msg_ping(nonce=self.ping_counter))
+        received_pong = False
+        sleep_time = 0.05
+        while not received_pong and timeout > 0:
+            time.sleep(sleep_time)
+            timeout -= sleep_time
+            with mininode_lock:
+                if self.last_pong.nonce == self.ping_counter:
+                    received_pong = True
+        self.ping_counter += 1
+        return received_pong
+
+
+class VersionBitsWarningTest(BitcoinTestFramework):
+    def __init__(self):
+        super().__init__()
+        self.setup_clean_chain = True
+        self.num_nodes = 1
+
+    def setup_network(self):
+        self.alert_filename = os.path.join(self.options.tmpdir, "alert.txt")
+        # Open and close to create zero-length file
+        with open(self.alert_filename, 'w', encoding='utf8') as _:
+            pass
+        self.extra_args = [["-alertnotify=echo %s >> \"" + self.alert_filename + "\""]]
+        self.nodes = start_nodes(self.num_nodes, self.options.tmpdir, self.extra_args)
+
+    # Send numblocks blocks via peer with nVersionToUse set.
+    def send_blocks_with_version(self, peer, numblocks, nVersionToUse):
+        tip = self.nodes[0].getbestblockhash()
+        height = self.nodes[0].getblockcount()
+        block_time = self.nodes[0].getblockheader(tip)["time"]+1
+        tip = int(tip, 16)
+
+        for _ in range(numblocks):
+            block = create_block(tip, create_coinbase(height+1), block_time)
+            block.nVersion = nVersionToUse
+            block.solve()
+            peer.send_message(msg_block(block))
+            block_time += 1
+            height += 1
+            tip = block.sha256
+        peer.sync_with_ping()
+
+    def test_versionbits_in_alert_file(self):
+        with open(self.alert_filename, 'r', encoding='utf8') as f:
+            alert_text = f.read()
+        assert(VB_PATTERN.match(alert_text))
+
+    def run_test(self):
+        # Setup the p2p connection and start up the network thread.
+        test_node = TestNode()
+
+        connections = []
+        connections.append(NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_node))
+        test_node.add_connection(connections[0])
+
+        NetworkThread().start() # Start up network handling in another thread
+
+        # Test logic begins here
+        test_node.wait_for_verack()
+
+        # 1. Have the node mine one period worth of blocks
+        self.nodes[0].generate(VB_PERIOD)
+
+        # 2. Now build one period of blocks on the tip, with < VB_THRESHOLD
+        # blocks signaling some unknown bit.
+        nVersion = VB_TOP_BITS | (1<<VB_UNKNOWN_BIT)
+        self.send_blocks_with_version(test_node, VB_THRESHOLD-1, nVersion)
+
+        # Fill rest of period with regular version blocks
+        self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD + 1)
+        # Check that we're not getting any versionbit-related errors in
+        # get*info()
+        assert(not VB_PATTERN.match(self.nodes[0].getinfo()["errors"]))
+        assert(not VB_PATTERN.match(self.nodes[0].getmininginfo()["errors"]))
+        assert(not VB_PATTERN.match(self.nodes[0].getnetworkinfo()["warnings"]))
+
+        # 3. Now build one period of blocks with >= VB_THRESHOLD blocks signaling
+        # some unknown bit
+        self.send_blocks_with_version(test_node, VB_THRESHOLD, nVersion)
+        self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD)
+        # Might not get a versionbits-related alert yet, as we should
+        # have gotten a different alert due to more than 51/100 blocks
+        # being of unexpected version.
+        # Check that get*info() shows some kind of error.
+        assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getinfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getmininginfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getnetworkinfo()["warnings"])
+
+        # Mine a period worth of expected blocks so the generic block-version warning
+        # is cleared, and restart the node. This should move the versionbit state
+        # to ACTIVE.
+        self.nodes[0].generate(VB_PERIOD)
+        stop_nodes(self.nodes)
+        # Empty out the alert file
+        with open(self.alert_filename, 'w', encoding='utf8') as _:
+            pass
+        self.nodes = start_nodes(self.num_nodes, self.options.tmpdir, self.extra_args)
+
+        # Connecting one block should be enough to generate an error.
+        self.nodes[0].generate(1)
+        assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getinfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getmininginfo()["errors"])
+        assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getnetworkinfo()["warnings"])
+        stop_nodes(self.nodes)
+        self.test_versionbits_in_alert_file()
+
+        # Test framework expects the node to still be running...
+        self.nodes = start_nodes(self.num_nodes, self.options.tmpdir, self.extra_args)
+
+if __name__ == '__main__':
+    VersionBitsWarningTest().main()