protocol: introduce QSENDRECSIGS net message.

src/net.h

@@ -685,6 +685,8 @@ class CNode
     std::atomic_bool fPauseRecv;
     std::atomic_bool fPauseSend;
 
+    // If true, we will announce/send him plain recovered sigs (usually true for full nodes)
+    std::atomic<bool> m_wants_recsigs{false};
     // True when the first message after the verack is received
     std::atomic<bool> fFirstMessageReceived{false};
     // True only if the first message received after verack is a mnauth

src/net_processing.cpp

@@ -1412,6 +1412,13 @@ bool static ProcessMessage(CNode* pfrom, std::string strCommand, CDataStream& vR
             pfrom->fDisconnect = true;
     }
 
+    else if (strCommand == NetMsgType::QSENDRECSIGS) {
+        bool b;
+        vRecv >> b;
+        pfrom->m_wants_recsigs = b;
+        return true;
+    }
+
     else if (strCommand == NetMsgType::INV) {
         std::vector<CInv> vInv;
         vRecv >> vInv;

src/protocol.cpp

@@ -54,6 +54,7 @@ const char* FINALBUDGETVOTE = "fbvote";
 const char* SYNCSTATUSCOUNT = "ssc";
 const char* GETMNLIST = "dseg";
 const char* QFCOMMITMENT = "qfcommit";
+const char* QSENDRECSIGS="qsendrecsigs";
 const char* MNAUTH="mnauth";
 }; // namespace NetMsgType
 
@@ -105,6 +106,7 @@ const static std::string allNetMessageTypes[] = {
     NetMsgType::SYNCSTATUSCOUNT,
     NetMsgType::MNBROADCAST2,
     NetMsgType::QFCOMMITMENT,
+    NetMsgType::QSENDRECSIGS,
     NetMsgType::MNAUTH
 };
 const static std::vector<std::string> allNetMessageTypesVec(allNetMessageTypes, allNetMessageTypes + ARRAYLEN(allNetMessageTypes));

src/protocol.h

@@ -278,6 +278,10 @@ extern const char* SYNCSTATUSCOUNT;
  * The qfcommit message is used to propagate LLMQ final commitments
  */
 extern const char* QFCOMMITMENT;
+/**
+ * The qsendrecsigs message is used to propagate LLMQ intra-quorum partial recovered signatures
+ */
+extern const char* QSENDRECSIGS;
 /**
  * The mnauth message is used authenticate MN connections
  */