[test] Test that -blocksonly nodes do not request high bandwidth mode.

Co-authored-by: Amiti Uttarwar <amiti@uttarwar.org>

test/functional/p2p_compactblocks_blocksonly.py

@@ -0,0 +1,84 @@
+#!/usr/bin/env python3
+# Copyright (c) 2021-2021 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 that a node in blocksonly mode does not request compact blocks."""
+
+from test_framework.messages import (
+    MSG_BLOCK,
+    MSG_CMPCT_BLOCK,
+    MSG_WITNESS_FLAG,
+    CBlock,
+    CBlockHeader,
+    CInv,
+    from_hex,
+    msg_block,
+    msg_headers,
+    msg_sendcmpct,
+)
+from test_framework.p2p import P2PInterface
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import assert_equal
+
+
+class P2PCompactBlocksBlocksOnly(BitcoinTestFramework):
+    def set_test_params(self):
+        self.extra_args = [["-blocksonly"], [], []]
+        self.num_nodes = 3
+
+    def setup_network(self):
+        self.setup_nodes()
+        # Start network with everyone disconnected
+        self.sync_all()
+
+    def build_block_on_tip(self):
+        blockhash = self.nodes[2].generate(1)[0]
+        block_hex = self.nodes[2].getblock(blockhash=blockhash, verbosity=0)
+        block = from_hex(CBlock(), block_hex)
+        block.rehash()
+        return block
+
+    def run_test(self):
+        # Nodes will only request hb compact blocks mode when they're out of IBD
+        for node in self.nodes:
+            assert not node.getblockchaininfo()['initialblockdownload']
+
+        p2p_conn_blocksonly = self.nodes[0].add_p2p_connection(P2PInterface())
+        p2p_conn_high_bw = self.nodes[1].add_p2p_connection(P2PInterface())
+        for conn in [p2p_conn_blocksonly, p2p_conn_high_bw]:
+            assert_equal(conn.message_count['sendcmpct'], 2)
+            conn.send_and_ping(msg_sendcmpct(announce=False, version=2))
+
+        # Nodes:
+        #   0 -> blocksonly
+        #   1 -> high bandwidth
+        #   2 -> miner
+        #
+        # Topology:
+        #   p2p_conn_blocksonly ---> node0
+        #   p2p_conn_high_bw    ---> node1
+        #   node2 (no connections)
+        #
+        # node2 produces blocks that are passed to the rest of the nodes
+        # through the respective p2p connections.
+
+        self.log.info("Test that -blocksonly nodes do not select peers for BIP152 high bandwidth mode")
+
+        block0 = self.build_block_on_tip()
+
+        # A -blocksonly node should not request BIP152 high bandwidth mode upon
+        # receiving a new valid block at the tip.
+        p2p_conn_blocksonly.send_and_ping(msg_block(block0))
+        assert_equal(int(self.nodes[0].getbestblockhash(), 16), block0.sha256)
+        assert_equal(p2p_conn_blocksonly.message_count['sendcmpct'], 2)
+        assert_equal(p2p_conn_blocksonly.last_message['sendcmpct'].announce, False)
+
+        # A normal node participating in transaction relay should request BIP152
+        # high bandwidth mode upon receiving a new valid block at the tip.
+        p2p_conn_high_bw.send_and_ping(msg_block(block0))
+        assert_equal(int(self.nodes[1].getbestblockhash(), 16), block0.sha256)
+        p2p_conn_high_bw.wait_until(lambda: p2p_conn_high_bw.message_count['sendcmpct'] == 3)
+        assert_equal(p2p_conn_high_bw.last_message['sendcmpct'].announce, True)
+
+if __name__ == '__main__':
+    P2PCompactBlocksBlocksOnly().main()

test/functional/test_runner.py

@@ -98,6 +98,7 @@ BASE_SCRIPTS = [
     'rpc_fundrawtransaction.py --legacy-wallet',
     'rpc_fundrawtransaction.py --descriptors',
     'p2p_compactblocks.py',
+    'p2p_compactblocks_blocksonly.py',
     'feature_segwit.py --legacy-wallet',
     # vv Tests less than 2m vv
     'wallet_basic.py --legacy-wallet',