Merge #17785: p2p: Unify Send and Receive protocol versions

ddefb5c0b759950942ac03f28c43b548af7b4033 p2p: Use the greatest common version in peer logic (Hennadii Stepanov)
e084d45562b94827b3a7873895882fcaae9f4d48 p2p: Remove SetCommonVersion() from VERACK handler (Hennadii Stepanov)
8d2026796a6f7add0c2cda9806e759817d1eae6f refactor: Rename local variable nSendVersion (Hennadii Stepanov)
e9a6d8b13b0558b17cdafbd32fd2663b4138ff11 p2p: Unify Send and Receive protocol versions (Hennadii Stepanov)

Pull request description:

  On master (6fef85bfa3cd7f76e83b8b57f9e4acd63eb664ec) `CNode` has two members to keep protocol version:
  - `nRecvVersion` for received messages
  - `nSendVersion` for messages to send

  After exchanging with `VERSION` and `VERACK` messages via protocol version `INIT_PROTO_VERSION`, both nodes set `nRecvVersion` _and_ `nSendVersion` to _the same_ value which is the greatest common protocol version.

  This PR:
  - replaces two `CNode` members, `nRecvVersion` `nSendVersion`, with `m_greatest_common_version`
  - removes duplicated getter and setter

  There is no change in behavior on the P2P network.

ACKs for top commit:
  jnewbery:
    ACK ddefb5c0b759950942ac03f28c43b548af7b4033
  naumenkogs:
    ACK ddefb5c0b759950942ac03f28c43b548af7b4033
  fjahr:
    Code review ACK ddefb5c0b759950942ac03f28c43b548af7b4033
  amitiuttarwar:
    code review but untested ACK ddefb5c0b7
  benthecarman:
    utACK `ddefb5c`

Tree-SHA512: 5305538dbaa5426b923b0afd20bdef4f248d310855d1d78427210c00716c67b7cb691515c421716b6157913e453076e293b10ff5fd2cd26a8e5375d42da7809d

3 files changed, 12 insertions, 17 deletions

diff --git a/src/test/fuzz/net.cpp b/src/test/fuzz/net.cpp
index cd0c93b8d0..a85c353243 100644
--- a/src/test/fuzz/net.cpp
+++ b/src/test/fuzz/net.cpp
@@ -48,7 +48,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
                fuzzed_data_provider.ConsumeRandomLengthString(32),
                fuzzed_data_provider.PickValueInArray({ConnectionType::INBOUND, ConnectionType::OUTBOUND_FULL_RELAY, ConnectionType::MANUAL, ConnectionType::FEELER, ConnectionType::BLOCK_RELAY, ConnectionType::ADDR_FETCH})};
     while (fuzzed_data_provider.ConsumeBool()) {
-        switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 12)) {
+        switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 11)) {
         case 0: {
             node.CloseSocketDisconnect();
             break;
@@ -58,7 +58,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             break;
         }
         case 2: {
-            node.SetSendVersion(fuzzed_data_provider.ConsumeIntegral<int>());
+            node.SetCommonVersion(fuzzed_data_provider.ConsumeIntegral<int>());
             break;
         }
         case 3: {
@@ -71,21 +71,17 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             break;
         }
         case 4: {
-            node.SetRecvVersion(fuzzed_data_provider.ConsumeIntegral<int>());
-            break;
-        }
-        case 5: {
             const CNode* add_ref_node = node.AddRef();
             assert(add_ref_node == &node);
             break;
         }
-        case 6: {
+        case 5: {
             if (node.GetRefCount() > 0) {
                 node.Release();
             }
             break;
         }
-        case 7: {
+        case 6: {
             if (node.m_addr_known == nullptr) {
                 break;
             }
@@ -96,7 +92,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             node.AddAddressKnown(*addr_opt);
             break;
         }
-        case 8: {
+        case 7: {
             if (node.m_addr_known == nullptr) {
                 break;
             }
@@ -108,7 +104,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             node.PushAddress(*addr_opt, fast_random_context);
             break;
         }
-        case 9: {
+        case 8: {
             const std::optional<CInv> inv_opt = ConsumeDeserializable<CInv>(fuzzed_data_provider);
             if (!inv_opt) {
                 break;
@@ -116,11 +112,11 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             node.AddKnownTx(inv_opt->hash);
             break;
         }
-        case 10: {
+        case 9: {
             node.PushTxInventory(ConsumeUInt256(fuzzed_data_provider));
             break;
         }
-        case 11: {
+        case 10: {
             const std::optional<CService> service_opt = ConsumeDeserializable<CService>(fuzzed_data_provider);
             if (!service_opt) {
                 break;
@@ -128,7 +124,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
             node.SetAddrLocal(*service_opt);
             break;
         }
-        case 12: {
+        case 11: {
             const std::vector<uint8_t> b = ConsumeRandomLengthByteVector(fuzzed_data_provider);
             bool complete;
             node.ReceiveMsgBytes((const char*)b.data(), b.size(), complete);
@@ -143,10 +139,9 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     (void)node.GetLocalNonce();
     (void)node.GetLocalServices();
     (void)node.GetMyStartingHeight();
-    (void)node.GetRecvVersion();
     const int ref_count = node.GetRefCount();
     assert(ref_count >= 0);
-    (void)node.GetSendVersion();
+    (void)node.GetCommonVersion();
     (void)node.RelayAddrsWithConn();
 
     const NetPermissionFlags net_permission_flags = fuzzed_data_provider.ConsumeBool() ?
diff --git a/src/test/fuzz/process_message.cpp b/src/test/fuzz/process_message.cpp
index 3d6947ca92..3ef03137ec 100644
--- a/src/test/fuzz/process_message.cpp
+++ b/src/test/fuzz/process_message.cpp
@@ -71,7 +71,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
     CNode& p2p_node = *MakeUnique<CNode>(0, ServiceFlags(NODE_NETWORK | NODE_WITNESS | NODE_BLOOM), 0, INVALID_SOCKET, CAddress{CService{in_addr{0x0100007f}, 7777}, NODE_NETWORK}, 0, 0, CAddress{}, std::string{}, ConnectionType::OUTBOUND_FULL_RELAY).release();
     p2p_node.fSuccessfullyConnected = true;
     p2p_node.nVersion = PROTOCOL_VERSION;
-    p2p_node.SetSendVersion(PROTOCOL_VERSION);
+    p2p_node.SetCommonVersion(PROTOCOL_VERSION);
     connman.AddTestNode(p2p_node);
     g_setup->m_node.peerman->InitializeNode(&p2p_node);
     try {
diff --git a/src/test/fuzz/process_messages.cpp b/src/test/fuzz/process_messages.cpp
index c9433d325a..f722eeac3a 100644
--- a/src/test/fuzz/process_messages.cpp
+++ b/src/test/fuzz/process_messages.cpp
@@ -51,7 +51,7 @@ void test_one_input(const std::vector<uint8_t>& buffer)
         p2p_node.fSuccessfullyConnected = true;
         p2p_node.fPauseSend = false;
         p2p_node.nVersion = PROTOCOL_VERSION;
-        p2p_node.SetSendVersion(PROTOCOL_VERSION);
+        p2p_node.SetCommonVersion(PROTOCOL_VERSION);
         g_setup->m_node.peerman->InitializeNode(&p2p_node);
 
         connman.AddTestNode(p2p_node);