refactor: Pass CNode& to ProcessMessages and SendMessages

diff --git a/src/net.cpp b/src/net.cpp
index 6b79e913..646fe9e9 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -3139,12 +3139,12 @@ void CConnman::ThreadMessageHandler()
                     continue;
 
                 // Receive messages
-                bool fMoreNodeWork = m_msgproc->ProcessMessages(pnode, flagInterruptMsgProc);
+                bool fMoreNodeWork{m_msgproc->ProcessMessages(*pnode, flagInterruptMsgProc)};
                 fMoreWork |= (fMoreNodeWork && !pnode->fPauseSend);
                 if (flagInterruptMsgProc)
                     return;
                 // Send messages
-                m_msgproc->SendMessages(pnode);
+                m_msgproc->SendMessages(*pnode);
 
                 if (flagInterruptMsgProc)
                     return;
diff --git a/src/net.h b/src/net.h
index 1e4e9124..1f7bbe4a 100644
--- a/src/net.h
+++ b/src/net.h
@@ -1043,21 +1043,21 @@ public:
     virtual bool HasAllDesirableServiceFlags(ServiceFlags services) const = 0;
 
     /**
-    * Process protocol messages received from a given node
-    *
-    * @param[in]   pnode           The node which we have received messages from.
-    * @param[in]   interrupt       Interrupt condition for processing threads
-    * @return                      True if there is more work to be done
-    */
-    virtual bool ProcessMessages(CNode* pnode, std::atomic<bool>& interrupt) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex) = 0;
+     * Process protocol messages received from a given node
+     *
+     * @param[in]   node            The node which we have received messages from.
+     * @param[in]   interrupt       Interrupt condition for processing threads
+     * @return                      True if there is more work to be done
+     */
+    virtual bool ProcessMessages(CNode& node, std::atomic<bool>& interrupt) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex) = 0;
 
     /**
-    * Send queued protocol messages to a given node.
-    *
-    * @param[in]   pnode           The node which we are sending messages to.
-    * @return                      True if there is more work to be done
-    */
-    virtual bool SendMessages(CNode* pnode) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex) = 0;
+     * Send queued protocol messages to a given node.
+     *
+     * @param[in]   node            The node which we are sending messages to.
+     * @return                      True if there is more work to be done
+     */
+    virtual bool SendMessages(CNode& node) EXCLUSIVE_LOCKS_REQUIRED(g_msgproc_mutex) = 0;
 
 
 protected:
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 34425948..3f8c2217 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -529,9 +529,9 @@ public:
     void InitializeNode(const CNode& node, ServiceFlags our_services) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_tx_download_mutex);
     void FinalizeNode(const CNode& node) override EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_headers_presync_mutex, !m_tx_download_mutex);
     bool HasAllDesirableServiceFlags(ServiceFlags services) const override;
-    bool ProcessMessages(CNode* pfrom, std::atomic<bool>& interrupt) override
+    bool ProcessMessages(CNode& node, std::atomic<bool>& interrupt) override
         EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_most_recent_block_mutex, !m_headers_presync_mutex, g_msgproc_mutex, !m_tx_download_mutex);
-    bool SendMessages(CNode* pto) override
+    bool SendMessages(CNode& node) override
         EXCLUSIVE_LOCKS_REQUIRED(!m_peer_mutex, !m_most_recent_block_mutex, g_msgproc_mutex, !m_tx_download_mutex);
 
     /** Implement PeerManager */
@@ -5181,11 +5181,12 @@ bool PeerManagerImpl::MaybeDiscourageAndDisconnect(CNode& pnode, Peer& peer)
     return true;
 }
 
-bool PeerManagerImpl::ProcessMessages(CNode* pfrom, std::atomic<bool>& interruptMsgProc)
+bool PeerManagerImpl::ProcessMessages(CNode& node, std::atomic<bool>& interruptMsgProc)
 {
     AssertLockNotHeld(m_tx_download_mutex);
     AssertLockHeld(g_msgproc_mutex);
 
+    CNode* pfrom{&node}; // alias removed in a later commit.
     PeerRef peer = GetPeerRef(pfrom->GetId());
     if (peer == nullptr) return false;
 
@@ -5683,11 +5684,12 @@ bool PeerManagerImpl::SetupAddressRelay(const CNode& node, Peer& peer)
     return true;
 }
 
-bool PeerManagerImpl::SendMessages(CNode* pto)
+bool PeerManagerImpl::SendMessages(CNode& node)
 {
     AssertLockNotHeld(m_tx_download_mutex);
     AssertLockHeld(g_msgproc_mutex);
 
+    CNode* pto{&node}; // alias removed in a later commit
     PeerRef peer = GetPeerRef(pto->GetId());
     if (!peer) return false;
     const Consensus::Params& consensusParams = m_chainparams.GetConsensus();
diff --git a/src/test/denialofservice_tests.cpp b/src/test/denialofservice_tests.cpp
index 0dc03230..776a1878 100644
--- a/src/test/denialofservice_tests.cpp
+++ b/src/test/denialofservice_tests.cpp
@@ -81,7 +81,7 @@ BOOST_AUTO_TEST_CASE(outbound_slow_chain_eviction)
     }
 
     // Test starts here
-    BOOST_CHECK(peerman.SendMessages(&dummyNode1)); // should result in getheaders
+    BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in getheaders
 
     {
         LOCK(dummyNode1.cs_vSend);
@@ -93,7 +93,7 @@ BOOST_AUTO_TEST_CASE(outbound_slow_chain_eviction)
     int64_t nStartTime = GetTime();
     // Wait 21 minutes
     SetMockTime(nStartTime+21*60);
-    BOOST_CHECK(peerman.SendMessages(&dummyNode1)); // should result in getheaders
+    BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in getheaders
     {
         LOCK(dummyNode1.cs_vSend);
         const auto& [to_send, _more, _msg_type] = dummyNode1.m_transport->GetBytesToSend(false);
@@ -101,7 +101,7 @@ BOOST_AUTO_TEST_CASE(outbound_slow_chain_eviction)
     }
     // Wait 3 more minutes
     SetMockTime(nStartTime+24*60);
-    BOOST_CHECK(peerman.SendMessages(&dummyNode1)); // should result in disconnect
+    BOOST_CHECK(peerman.SendMessages(dummyNode1)); // should result in disconnect
     BOOST_CHECK(dummyNode1.fDisconnect == true);
 
     peerman.FinalizeNode(dummyNode1);
@@ -336,7 +336,7 @@ BOOST_AUTO_TEST_CASE(peer_discouragement)
     nodes[0]->fSuccessfullyConnected = true;
     connman->AddTestNode(*nodes[0]);
     peerLogic->UnitTestMisbehaving(nodes[0]->GetId()); // Should be discouraged
-    BOOST_CHECK(peerLogic->SendMessages(nodes[0]));
+    BOOST_CHECK(peerLogic->SendMessages(*nodes[0]));
 
     BOOST_CHECK(banman->IsDiscouraged(addr[0]));
     BOOST_CHECK(nodes[0]->fDisconnect);
@@ -356,7 +356,7 @@ BOOST_AUTO_TEST_CASE(peer_discouragement)
     peerLogic->InitializeNode(*nodes[1], NODE_NETWORK);
     nodes[1]->fSuccessfullyConnected = true;
     connman->AddTestNode(*nodes[1]);
-    BOOST_CHECK(peerLogic->SendMessages(nodes[1]));
+    BOOST_CHECK(peerLogic->SendMessages(*nodes[1]));
     // [0] is still discouraged/disconnected.
     BOOST_CHECK(banman->IsDiscouraged(addr[0]));
     BOOST_CHECK(nodes[0]->fDisconnect);
@@ -364,7 +364,7 @@ BOOST_AUTO_TEST_CASE(peer_discouragement)
     BOOST_CHECK(!banman->IsDiscouraged(addr[1]));
     BOOST_CHECK(!nodes[1]->fDisconnect);
     peerLogic->UnitTestMisbehaving(nodes[1]->GetId());
-    BOOST_CHECK(peerLogic->SendMessages(nodes[1]));
+    BOOST_CHECK(peerLogic->SendMessages(*nodes[1]));
     // Expect both [0] and [1] to be discouraged/disconnected now.
     BOOST_CHECK(banman->IsDiscouraged(addr[0]));
     BOOST_CHECK(nodes[0]->fDisconnect);
@@ -388,7 +388,7 @@ BOOST_AUTO_TEST_CASE(peer_discouragement)
     nodes[2]->fSuccessfullyConnected = true;
     connman->AddTestNode(*nodes[2]);
     peerLogic->UnitTestMisbehaving(nodes[2]->GetId());
-    BOOST_CHECK(peerLogic->SendMessages(nodes[2]));
+    BOOST_CHECK(peerLogic->SendMessages(*nodes[2]));
     BOOST_CHECK(banman->IsDiscouraged(addr[0]));
     BOOST_CHECK(banman->IsDiscouraged(addr[1]));
     BOOST_CHECK(banman->IsDiscouraged(addr[2]));
@@ -431,7 +431,7 @@ BOOST_AUTO_TEST_CASE(DoS_bantime)
     dummyNode.fSuccessfullyConnected = true;
 
     peerLogic->UnitTestMisbehaving(dummyNode.GetId());
-    BOOST_CHECK(peerLogic->SendMessages(&dummyNode));
+    BOOST_CHECK(peerLogic->SendMessages(dummyNode));
     BOOST_CHECK(banman->IsDiscouraged(addr));
 
     peerLogic->FinalizeNode(dummyNode);
diff --git a/src/test/fuzz/p2p_handshake.cpp b/src/test/fuzz/p2p_handshake.cpp
index aec7387e..bf9b7445 100644
--- a/src/test/fuzz/p2p_handshake.cpp
+++ b/src/test/fuzz/p2p_handshake.cpp
@@ -100,7 +100,7 @@ FUZZ_TARGET(p2p_handshake, .init = ::initialize)
                 more_work = connman.ProcessMessagesOnce(connection);
             } catch (const std::ios_base::failure&) {
             }
-            peerman->SendMessages(&connection);
+            peerman->SendMessages(connection);
         }
     }
 
diff --git a/src/test/fuzz/p2p_headers_presync.cpp b/src/test/fuzz/p2p_headers_presync.cpp
index d5871374..4aa56686 100644
--- a/src/test/fuzz/p2p_headers_presync.cpp
+++ b/src/test/fuzz/p2p_headers_presync.cpp
@@ -97,7 +97,7 @@ void HeadersSyncSetup::SendMessage(FuzzedDataProvider& fuzzed_data_provider, CSe
         connman.ProcessMessagesOnce(connection);
     } catch (const std::ios_base::failure&) {
     }
-    m_node.peerman->SendMessages(&connection);
+    m_node.peerman->SendMessages(connection);
 }
 
 CBlockHeader ConsumeHeader(FuzzedDataProvider& fuzzed_data_provider, const uint256& prev_hash, uint32_t prev_nbits)
diff --git a/src/test/fuzz/process_message.cpp b/src/test/fuzz/process_message.cpp
index ef8cb686..c03dfbd6 100644
--- a/src/test/fuzz/process_message.cpp
+++ b/src/test/fuzz/process_message.cpp
@@ -121,7 +121,7 @@ FUZZ_TARGET(process_message, .init = initialize_process_message)
             more_work = connman.ProcessMessagesOnce(p2p_node);
         } catch (const std::ios_base::failure&) {
         }
-        node.peerman->SendMessages(&p2p_node);
+        node.peerman->SendMessages(p2p_node);
     }
     node.validation_signals->SyncWithValidationInterfaceQueue();
     node.connman->StopNodes();
diff --git a/src/test/fuzz/process_messages.cpp b/src/test/fuzz/process_messages.cpp
index f36f528b..8997dbac 100644
--- a/src/test/fuzz/process_messages.cpp
+++ b/src/test/fuzz/process_messages.cpp
@@ -120,7 +120,7 @@ FUZZ_TARGET(process_messages, .init = initialize_process_messages)
                 more_work = connman.ProcessMessagesOnce(random_node);
             } catch (const std::ios_base::failure&) {
             }
-            node.peerman->SendMessages(&random_node);
+            node.peerman->SendMessages(random_node);
         }
     }
     node.validation_signals->SyncWithValidationInterfaceQueue();
diff --git a/src/test/fuzz/util/net.h b/src/test/fuzz/util/net.h
index 90c018a4..d19c4cbf 100644
--- a/src/test/fuzz/util/net.h
+++ b/src/test/fuzz/util/net.h
@@ -150,9 +150,9 @@ public:
 
     virtual bool HasAllDesirableServiceFlags(ServiceFlags) const override { return m_fdp.ConsumeBool(); }
 
-    virtual bool ProcessMessages(CNode*, std::atomic<bool>&) override { return m_fdp.ConsumeBool(); }
+    virtual bool ProcessMessages(CNode&, std::atomic<bool>&) override { return m_fdp.ConsumeBool(); }
 
-    virtual bool SendMessages(CNode*) override { return m_fdp.ConsumeBool(); }
+    virtual bool SendMessages(CNode&) override { return m_fdp.ConsumeBool(); }
 
 private:
     FuzzedDataProvider& m_fdp;
diff --git a/src/test/net_tests.cpp b/src/test/net_tests.cpp
index ff2083de..72a06a68 100644
--- a/src/test/net_tests.cpp
+++ b/src/test/net_tests.cpp
@@ -847,7 +847,7 @@ BOOST_AUTO_TEST_CASE(initial_advertise_from_version_message)
 
     m_node.peerman->InitializeNode(peer, NODE_NETWORK);
 
-    m_node.peerman->SendMessages(&peer);
+    m_node.peerman->SendMessages(peer);
     connman.FlushSendBuffer(peer); // Drop sent version message
 
     auto msg_version_receive =
@@ -857,7 +857,7 @@ BOOST_AUTO_TEST_CASE(initial_advertise_from_version_message)
     bool more_work{connman.ProcessMessagesOnce(peer)};
     Assert(!more_work);
 
-    m_node.peerman->SendMessages(&peer);
+    m_node.peerman->SendMessages(peer);
     connman.FlushSendBuffer(peer); // Drop sent verack message
 
     Assert(connman.ReceiveMsgFrom(peer, NetMsg::Make(NetMsgType::VERACK)));
@@ -890,7 +890,7 @@ BOOST_AUTO_TEST_CASE(initial_advertise_from_version_message)
         }
     };
 
-    m_node.peerman->SendMessages(&peer);
+    m_node.peerman->SendMessages(peer);
 
     BOOST_CHECK(sent);
 
diff --git a/src/test/util/net.cpp b/src/test/util/net.cpp
index 0f59e0d6..0979e2ae 100644
--- a/src/test/util/net.cpp
+++ b/src/test/util/net.cpp
@@ -31,7 +31,7 @@ void ConnmanTestMsg::Handshake(CNode& node,
     auto& connman{*this};
 
     peerman.InitializeNode(node, local_services);
-    peerman.SendMessages(&node);
+    peerman.SendMessages(node);
     FlushSendBuffer(node); // Drop the version message added by SendMessages.
 
     CSerializedNetMsg msg_version{
@@ -52,7 +52,7 @@ void ConnmanTestMsg::Handshake(CNode& node,
     (void)connman.ReceiveMsgFrom(node, std::move(msg_version));
     node.fPauseSend = false;
     connman.ProcessMessagesOnce(node);
-    peerman.SendMessages(&node);
+    peerman.SendMessages(node);
     FlushSendBuffer(node); // Drop the verack message added by SendMessages.
     if (node.fDisconnect) return;
     assert(node.nVersion == version);
@@ -66,7 +66,7 @@ void ConnmanTestMsg::Handshake(CNode& node,
         (void)connman.ReceiveMsgFrom(node, std::move(msg_verack));
         node.fPauseSend = false;
         connman.ProcessMessagesOnce(node);
-        peerman.SendMessages(&node);
+        peerman.SendMessages(node);
         assert(node.fSuccessfullyConnected == true);
     }
 }
diff --git a/src/test/util/net.h b/src/test/util/net.h
index ee02d404..732aefb3 100644
--- a/src/test/util/net.h
+++ b/src/test/util/net.h
@@ -101,7 +101,7 @@ struct ConnmanTestMsg : public CConnman {
 
     bool ProcessMessagesOnce(CNode& node) EXCLUSIVE_LOCKS_REQUIRED(NetEventsInterface::g_msgproc_mutex)
     {
-        return m_msgproc->ProcessMessages(&node, flagInterruptMsgProc);
+        return m_msgproc->ProcessMessages(node, flagInterruptMsgProc);
     }
 
     void NodeReceiveMsgBytes(CNode& node, std::span<const uint8_t> msg_bytes, bool& complete) const;