net: Fix sent reject messages for blocks and transactions

Ever since we #5913 have been sending invalid reject messages
for transactions and blocks.

src/main.cpp

@@ -4824,7 +4824,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
                 pfrom->id,
                 FormatStateMessage(state));
             if (state.GetRejectCode() < REJECT_INTERNAL) // Never send AcceptToMemoryPool's internal codes over P2P
-                pfrom->PushMessage("reject", strCommand, state.GetRejectCode(),
+                pfrom->PushMessage("reject", strCommand, (unsigned char)state.GetRejectCode(),
                                    state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), inv.hash);
             if (nDoS > 0)
                 Misbehaving(pfrom->GetId(), nDoS);
@@ -4954,7 +4954,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv,
         int nDoS;
         if (state.IsInvalid(nDoS)) {
             assert (state.GetRejectCode() < REJECT_INTERNAL); // Blocks are never rejected with internal reject codes
-            pfrom->PushMessage("reject", strCommand, state.GetRejectCode(),
+            pfrom->PushMessage("reject", strCommand, (unsigned char)state.GetRejectCode(),
                                state.GetRejectReason().substr(0, MAX_REJECT_MESSAGE_LENGTH), inv.hash);
             if (nDoS > 0) {
                 LOCK(cs_main);