Check for hop_limit and also update next hop when hop_start == hop_limit on ACK

Also check for broadcast in `getNextHop()`

src/main.cpp

@@ -653,7 +653,7 @@ void setup()
     // but we need to do this after main cpu init (esp32setup), because we need the random seed set
     nodeDB = new NodeDB;
 
-    // If we're taking on the repeater role, use flood router and turn off 3V3_S rail because peripherals are not needed
+    // If we're taking on the repeater role, use NextHopRouter and turn off 3V3_S rail because peripherals are not needed
     if (config.device.role == meshtastic_Config_DeviceConfig_Role_REPEATER) {
         router = new NextHopRouter();
 #ifdef PIN_3V3_EN

src/mesh/NextHopRouter.cpp

@@ -54,14 +54,13 @@ void NextHopRouter::sniffReceived(const meshtastic_MeshPacket *p, const meshtast
     if (isAckorReply) {
         // Update next-hop for the original transmitter of this successful transmission to the relay node, but ONLY if "from" is
         // not 0 (means implicit ACK) and original packet was also relayed by this node, or we sent it directly to the destination
-        if (p->from != 0 && p->relay_node) {
+        if (p->from != 0) {
             meshtastic_NodeInfoLite *origTx = nodeDB->getMeshNode(p->from);
             if (origTx) {
                 // Either relayer of ACK was also a relayer of the packet, or we were the relayer and the ACK came directly from
                 // the destination
                 if (wasRelayer(p->relay_node, p->decoded.request_id, p->to) ||
-                    (wasRelayer(ourRelayID, p->decoded.request_id, p->to) &&
-                     p->relay_node == nodeDB->getLastByteOfNodeNum(p->from))) {
+                    (wasRelayer(ourRelayID, p->decoded.request_id, p->to) && p->hop_start != 0 && p->hop_start == p->hop_limit)) {
                     if (origTx->next_hop != p->relay_node) { // Not already set
                         LOG_INFO("Update next hop of 0x%x to 0x%x based on ACK/reply", p->from, p->relay_node);
                         origTx->next_hop = p->relay_node;
@@ -76,18 +75,18 @@ void NextHopRouter::sniffReceived(const meshtastic_MeshPacket *p, const meshtast
         }
     }
 
-    if (isRebroadcaster()) {
-        if (!isToUs(p) && !isFromUs(p)) {
-            if (p->next_hop == NO_NEXT_HOP_PREFERENCE || p->next_hop == ourRelayID) {
+    if (!isToUs(p) && !isFromUs(p) && p->hop_limit > 0) {
+        if (p->next_hop == NO_NEXT_HOP_PREFERENCE || p->next_hop == ourRelayID) {
+            if (isRebroadcaster()) {
                 meshtastic_MeshPacket *tosend = packetPool.allocCopy(*p); // keep a copy because we will be sending it
                 LOG_INFO("Relaying received message coming from %x", p->relay_node);
 
                 tosend->hop_limit--; // bump down the hop count
                 NextHopRouter::send(tosend);
-            } // else don't relay
+            } else {
+                LOG_DEBUG("Not rebroadcasting: Role = CLIENT_MUTE or Rebroadcast Mode = NONE");
+            }
         }
-    } else {
-        LOG_DEBUG("Not rebroadcasting: Role = CLIENT_MUTE or Rebroadcast Mode = NONE");
     }
     // handle the packet as normal
     Router::sniffReceived(p, c);
@@ -99,6 +98,10 @@ void NextHopRouter::sniffReceived(const meshtastic_MeshPacket *p, const meshtast
  */
 uint8_t NextHopRouter::getNextHop(NodeNum to, uint8_t relay_node)
 {
+    // When we're a repeater router->sniffReceived will call NextHopRouter directly without checking for broadcast
+    if (isBroadcast(to))
+        return NO_NEXT_HOP_PREFERENCE;
+
     meshtastic_NodeInfoLite *node = nodeDB->getMeshNode(to);
     if (node && node->next_hop) {
         // We are careful not to return the relay node as the next hop

src/mesh/PacketHistory.cpp

@@ -54,8 +54,8 @@ bool PacketHistory::wasSeenRecently(const meshtastic_MeshPacket *p, bool withUpd
         // to handle it now
         uint8_t ourRelayID = nodeDB->getLastByteOfNodeNum(nodeDB->getNodeNum());
         if (found->sender != nodeDB->getNodeNum() && found->next_hop != NO_NEXT_HOP_PREFERENCE &&
-            p->next_hop == NO_NEXT_HOP_PREFERENCE && found->next_hop != ourRelayID && p->relay_node != 0 &&
-            wasRelayer(p->relay_node, found) && !wasRelayer(ourRelayID, found) && !wasRelayer(found->next_hop, found)) {
+            p->next_hop == NO_NEXT_HOP_PREFERENCE && found->next_hop != ourRelayID && wasRelayer(p->relay_node, found) &&
+            !wasRelayer(ourRelayID, found) && !wasRelayer(found->next_hop, found)) {
             LOG_INFO("Fallback to flooding, consider unseen relay_node=0x%x", p->relay_node);
             seenRecently = false;
         }
@@ -109,6 +109,9 @@ void PacketHistory::clearExpiredRecentPackets()
  * @return true if node was indeed a relayer, false if not */
 bool PacketHistory::wasRelayer(const uint8_t relayer, const uint32_t id, const NodeNum sender)
 {
+    if (relayer == 0)
+        return false;
+
     PacketRecord r = {.sender = sender, .id = id, .rxTimeMsec = 0, .next_hop = 0};
     auto found = recentPackets.find(r);
 

src/mesh/RadioInterface.cpp

@@ -315,10 +315,6 @@ void printPacket(const char *prefix, const meshtastic_MeshPacket *p)
         out += " encrypted";
     }
 
-    if (p->next_hop != 0)
-        out += DEBUG_PORT.mt_sprintf(" nextHop=0x%x", p->next_hop);
-    if (p->relay_node != 0)
-        out += DEBUG_PORT.mt_sprintf(" relay=0x%x", p->relay_node);
     if (p->rx_time != 0)
         out += DEBUG_PORT.mt_sprintf(" rxtime=%u", p->rx_time);
     if (p->rx_snr != 0.0)
@@ -329,6 +325,10 @@ void printPacket(const char *prefix, const meshtastic_MeshPacket *p)
         out += DEBUG_PORT.mt_sprintf(" via MQTT");
     if (p->hop_start != 0)
         out += DEBUG_PORT.mt_sprintf(" hopStart=%d", p->hop_start);
+    if (p->next_hop != 0)
+        out += DEBUG_PORT.mt_sprintf(" nextHop=0x%x", p->next_hop);
+    if (p->relay_node != 0)
+        out += DEBUG_PORT.mt_sprintf(" relay=0x%x", p->relay_node);
     if (p->priority != 0)
         out += DEBUG_PORT.mt_sprintf(" priority=%d", p->priority);
 

src/modules/Modules.cpp

@@ -245,4 +245,4 @@ void setupModules()
     // NOTE! This module must be added LAST because it likes to check for replies from other modules and avoid sending extra
     // acks
     routingModule = new RoutingModule();
-}
+}

src/modules/NeighborInfoModule.cpp

@@ -208,4 +208,4 @@ meshtastic_Neighbor *NeighborInfoModule::getOrCreateNeighbor(NodeNum originalSen
         neighbors.push_back(new_nbr);
     }
     return &neighbors.back();
-}
+}

src/modules/NeighborInfoModule.h

@@ -67,4 +67,4 @@ class NeighborInfoModule : public ProtobufModule<meshtastic_NeighborInfo>, priva
     void printNeighborInfo(const char *header, const meshtastic_NeighborInfo *np);
     void printNodeDBNeighbors();
 };
-extern NeighborInfoModule *neighborInfoModule;
+extern NeighborInfoModule *neighborInfoModule;