Move checksum check from net_processing to net

This removes the m_valid_checksum member from CNetMessage.  Instead,
GetMessage() returns an Optional.

Additionally, GetMessage() has been given an out parameter to be used to
hold error information.  For now it is specifically a uint32_t used to
hold the raw size of the corrupt message.

The checksum check is now done in GetMessage.

1 files changed, 13 insertions, 10 deletions

diff --git a/src/test/fuzz/p2p_transport_deserializer.cpp b/src/test/fuzz/p2p_transport_deserializer.cpp
index 732136330b..3e9cd3af38 100644
--- a/src/test/fuzz/p2p_transport_deserializer.cpp
+++ b/src/test/fuzz/p2p_transport_deserializer.cpp
@@ -32,16 +32,19 @@ void test_one_input(const std::vector<uint8_t>& buffer)
         n_bytes -= handled;
         if (deserializer.Complete()) {
             const std::chrono::microseconds m_time{std::numeric_limits<int64_t>::max()};
-            const CNetMessage msg = deserializer.GetMessage(Params().MessageStart(), m_time);
-            assert(msg.m_command.size() <= CMessageHeader::COMMAND_SIZE);
-            assert(msg.m_raw_message_size <= buffer.size());
-            assert(msg.m_raw_message_size == CMessageHeader::HEADER_SIZE + msg.m_message_size);
-            assert(msg.m_time == m_time);
-            if (msg.m_valid_header) {
-                assert(msg.m_valid_netmagic);
-            }
-            if (!msg.m_valid_netmagic) {
-                assert(!msg.m_valid_header);
+            uint32_t out_err_raw_size{0};
+            Optional<CNetMessage> result{deserializer.GetMessage(Params().MessageStart(), m_time, out_err_raw_size)};
+            if (result) {
+                assert(result->m_command.size() <= CMessageHeader::COMMAND_SIZE);
+                assert(result->m_raw_message_size <= buffer.size());
+                assert(result->m_raw_message_size == CMessageHeader::HEADER_SIZE + result->m_message_size);
+                assert(result->m_time == m_time);
+                if (result->m_valid_header) {
+                    assert(result->m_valid_netmagic);
+                }
+                if (!result->m_valid_netmagic) {
+                    assert(!result->m_valid_header);
+                }
             }
         }
     }