net: allow unconnected headerannouncements only once

Sjors · Sjors · commit fad8c5be6e05 · 2024-03-07T14:49:39.000+01:00
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
@@ -130,7 +130,7 @@ static constexpr double BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 0.5;
 /** Maximum number of headers to announce when relaying blocks with headers message.*/
 static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8;
 /** Maximum number of unconnecting headers announcements before DoS score */
-static const int MAX_NUM_UNCONNECTING_HEADERS_MSGS = 10;
+static const int MAX_NUM_UNCONNECTING_HEADERS_MSGS = 2;
 /** Minimum blocks required to signal NODE_NETWORK_LIMITED */
 static const unsigned int NODE_NETWORK_LIMITED_MIN_BLOCKS = 288;
 /** Window, in blocks, for connecting to NODE_NETWORK_LIMITED peers */
@@ -2544,8 +2544,7 @@ arith_uint256 PeerManagerImpl::GetAntiDoSWorkThreshold()
  *
  * We'll send a getheaders message in response to try to connect the chain.
  *
- * The peer can send up to MAX_NUM_UNCONNECTING_HEADERS_MSGS in a row that
- * don't connect before given DoS points.
+ * Allow this only once.
  *
  * Once a headers message is received that is valid and does connect,
  * m_num_unconnecting_headers_msgs gets reset back to 0.
diff --git a/test/functional/p2p_sendheaders.py b/test/functional/p2p_sendheaders.py
@@ -546,7 +546,7 @@ def test_nonnull_locators(self, test_node, inv_node):
         blocks = []
         # Now we test that if we repeatedly don't send connecting headers, we
         # don't go into an infinite loop trying to get them to connect.
-        MAX_NUM_UNCONNECTING_HEADERS_MSGS = 10
+        MAX_NUM_UNCONNECTING_HEADERS_MSGS = 2
         for _ in range(MAX_NUM_UNCONNECTING_HEADERS_MSGS + 1):
             blocks.append(create_block(tip, create_coinbase(height), block_time))
             blocks[-1].solve()
@@ -568,7 +568,7 @@ def test_nonnull_locators(self, test_node, inv_node):
         blocks = blocks[2:]
 
         # Now try to see how many unconnecting headers we can send
-        # before we get disconnected.  Should be 5*MAX_NUM_UNCONNECTING_HEADERS_MSGS
+        # before we get disconnected.  Should be MAX_NUM_UNCONNECTING_HEADERS_MSGS
         for i in range(MAX_NUM_UNCONNECTING_HEADERS_MSGS - 1):
             # Send a header that doesn't connect, check that we get a getheaders.
             with p2p_lock:

Original file line number	Diff line number	Diff line change
`@@ -130,7 +130,7 @@ static constexpr double BLOCK_DOWNLOAD_TIMEOUT_PER_PEER = 0.5;`
`130`	`130`	`/** Maximum number of headers to announce when relaying blocks with headers message.*/`
`131`	`131`	`static const unsigned int MAX_BLOCKS_TO_ANNOUNCE = 8;`
`132`	`132`	`/** Maximum number of unconnecting headers announcements before DoS score */`
`133`		`-static const int MAX_NUM_UNCONNECTING_HEADERS_MSGS = 10;`
	`133`	`+static const int MAX_NUM_UNCONNECTING_HEADERS_MSGS = 2;`
`134`	`134`	`/** Minimum blocks required to signal NODE_NETWORK_LIMITED */`
`135`	`135`	`static const unsigned int NODE_NETWORK_LIMITED_MIN_BLOCKS = 288;`
`136`	`136`	`/** Window, in blocks, for connecting to NODE_NETWORK_LIMITED peers */`
`@@ -2544,8 +2544,7 @@ arith_uint256 PeerManagerImpl::GetAntiDoSWorkThreshold()`
`2544`	`2544`	`*`
`2545`	`2545`	`* We'll send a getheaders message in response to try to connect the chain.`
`2546`	`2546`	`*`
`2547`		`- * The peer can send up to MAX_NUM_UNCONNECTING_HEADERS_MSGS in a row that`
`2548`		`- * don't connect before given DoS points.`
	`2547`	`+ * Allow this only once.`
`2549`	`2548`	`*`
`2550`	`2549`	`* Once a headers message is received that is valid and does connect,`
`2551`	`2550`	`* m_num_unconnecting_headers_msgs gets reset back to 0.`