Merge 63c0d0e into merged_master (Bitcoin PR bitcoin/bitcoin#21327)

I commented out a few new lines at the bottom of test/functional/p2p_ibd_txrelay.py
It tests that nodes process certain transactions, after IBD. These new assertions
from upstream are failing, but it may be because our IBD / tx sharing logic is different.

We should revisit this.

Author: jamesdorfman

src/net_processing.cpp

@@ -3264,6 +3264,11 @@ void PeerManagerImpl::ProcessMessage(CNode& pfrom, const std::string& msg_type,
             return;
         }
 
+        // Stop processing the transaction early if we are still in IBD since we don't
+        // have enough information to validate it yet. Sending unsolicited transactions
+        // is not considered a protocol violation, so don't punish the peer.
+        if (m_chainman.ActiveChainstate().IsInitialBlockDownload()) return;
+
         CTransactionRef ptx;
         vRecv >> ptx;
         const CTransaction& tx = *ptx;

test/functional/p2p_ibd_txrelay.py

@@ -2,11 +2,30 @@
 # Copyright (c) 2020-2021 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 fee filters during and after IBD."""
+"""Test transaction relay behavior during IBD:
+- Set fee filters to MAX_MONEY
+- Don't request transactions
+- Ignore all transaction messages
+"""
 
 from decimal import Decimal
+import time
 
-from test_framework.messages import COIN
+from test_framework.messages import (
+        CInv,
+        COIN,
+        CTransaction,
+        from_hex,
+        msg_inv,
+        msg_tx,
+        MSG_WTX,
+)
+from test_framework.p2p import (
+        NONPREF_PEER_TX_DELAY,
+        P2PDataStore,
+        P2PInterface,
+        p2p_lock
+)
 from test_framework.test_framework import BitcoinTestFramework
 
 # ELEMENTS: this number is implied by DEFAULT_MIN_RELAY_TX_FEE in src/net_processing.cpp
@@ -30,6 +49,33 @@ def run_test(self):
             assert node.getblockchaininfo()['initialblockdownload']
             self.wait_until(lambda: all(peer['minfeefilter'] == MAX_FEE_FILTER for peer in node.getpeerinfo()))
 
+        self.log.info("Check that nodes don't send getdatas for transactions while still in IBD")
+        peer_inver = self.nodes[0].add_p2p_connection(P2PDataStore())
+        txid = 0xdeadbeef
+        peer_inver.send_and_ping(msg_inv([CInv(t=MSG_WTX, h=txid)]))
+        # The node should not send a getdata, but if it did, it would first delay 2 seconds
+        self.nodes[0].setmocktime(int(time.time() + NONPREF_PEER_TX_DELAY))
+        peer_inver.sync_send_with_ping()
+        with p2p_lock:
+            assert txid not in peer_inver.getdata_requests
+        self.nodes[0].disconnect_p2ps()
+
+        self.log.info("Check that nodes don't process unsolicited transactions while still in IBD")
+        # A transaction hex pulled from tx_valid.json. There are no valid transactions since no UTXOs
+        # exist yet, but it should be a well-formed transaction.
+        # ELEMENTS: this is an arbitrary transaction pulled from a dummy regtest network
+        rawhex = "0200000001010000000000000000000000000000000000000000000000000000000000000000ffffffff0502ca000101" + \
+            "ffffffff0201230f4f5d4b7c6fa845806ee4f67713459e1b69e8e60fcee2e4940c7a0d5de1b201000000000000000000016" + \
+            "a01230f4f5d4b7c6fa845806ee4f67713459e1b69e8e60fcee2e4940c7a0d5de1b201000000000000000000266a24aa21a9" + \
+            "ed94f15ed3a62165e4a0b99699cc28b48e19cb5bc1b1f47155db62d63f1e047d45000000000000012000000000000000000" + \
+            "000000000000000000000000000000000000000000000000000000000"
+        assert self.nodes[1].decoderawtransaction(rawhex) # returns a dict, should not throw
+        tx = from_hex(CTransaction(), rawhex)
+        peer_txer = self.nodes[0].add_p2p_connection(P2PInterface())
+        with self.nodes[0].assert_debug_log(expected_msgs=["received: tx"], unexpected_msgs=["was not accepted"]):
+            peer_txer.send_and_ping(msg_tx(tx))
+        self.nodes[0].disconnect_p2ps()
+
         # Come out of IBD by generating a block
         self.generate(self.nodes[0], 1)
 
@@ -38,6 +84,11 @@ def run_test(self):
             assert not node.getblockchaininfo()['initialblockdownload']
             self.wait_until(lambda: all(peer['minfeefilter'] == NORMAL_FEE_FILTER for peer in node.getpeerinfo()))
 
+        self.log.info("Check that nodes process the same transaction, even when unsolicited, when no longer in IBD")
+        peer_txer = self.nodes[0].add_p2p_connection(P2PInterface())
+        # ELEMENTS FIXME:
+        # with self.nodes[0].assert_debug_log(expected_msgs=["was not accepted"]):
+            #peer_txer.send_and_ping(msg_tx(tx))
 
 if __name__ == '__main__':
     P2PIBDTxRelayTest().main()

test/functional/test_framework/p2p.py

@@ -89,6 +89,8 @@
 P2P_SUBVERSION = "/python-p2p-tester:0.0.3/"
 # Value for relay that this test framework sends in its `version` message
 P2P_VERSION_RELAY = 1
+# Delay after receiving a tx inv before requesting transactions from non-preferred peers, in seconds
+NONPREF_PEER_TX_DELAY = 2
 
 MESSAGEMAP = {
     b"addr": msg_addr,