From b305acf7e500f0855c51e039a6aba4627d327984 Mon Sep 17 00:00:00 2001
From: Mike Robbins <mrobbins@alum.mit.edu>
Date: Fri, 5 Sep 2025 15:10:37 -0700
Subject: [PATCH] Add FloodingRouter::roleAllowsCancelingDupe and condition for
 CLIENT_BASE

---
 src/mesh/FloodingRouter.cpp | 25 ++++++++++++++++++++++---
 src/mesh/FloodingRouter.h   |  3 +++
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/mesh/FloodingRouter.cpp b/src/mesh/FloodingRouter.cpp
index dbd458b61..ce9b91029 100644
--- a/src/mesh/FloodingRouter.cpp
+++ b/src/mesh/FloodingRouter.cpp
@@ -43,11 +43,30 @@ bool FloodingRouter::shouldFilterReceived(const meshtastic_MeshPacket *p)
     return Router::shouldFilterReceived(p);
 }
 
+bool FloodingRouter::roleAllowsCancelingDupe(const meshtastic_MeshPacket *p)
+{
+    if (config.device.role == meshtastic_Config_DeviceConfig_Role_ROUTER ||
+        config.device.role == meshtastic_Config_DeviceConfig_Role_REPEATER ||
+        config.device.role == meshtastic_Config_DeviceConfig_Role_ROUTER_LATE) {
+        // ROUTER, REPEATER, ROUTER_LATE should never cancel relaying a packet (i.e. we should always rebroadcast),
+        // even if we've heard another station rebroadcast it already.
+        return false;
+    }
+
+    if (config.device.role == meshtastic_Config_DeviceConfig_Role_CLIENT_BASE) {
+        // CLIENT_BASE: if the packet is from or to a favorited node,
+        // we should act like a ROUTER and should never cancel a rebroadcast (i.e. we should always rebroadcast),
+        // even if we've heard another station rebroadcast it already.
+        return !nodeDB->isFromOrToFavoritedNode(*p);
+    }
+
+    // All other roles (such as CLIENT) should cancel a rebroadcast if they hear another station's rebroadcast.
+    return true;
+}
+
 void FloodingRouter::perhapsCancelDupe(const meshtastic_MeshPacket *p)
 {
-    if (config.device.role != meshtastic_Config_DeviceConfig_Role_ROUTER &&
-        config.device.role != meshtastic_Config_DeviceConfig_Role_REPEATER &&
-        config.device.role != meshtastic_Config_DeviceConfig_Role_ROUTER_LATE &&
+    if (roleAllowsCancelingDupe(p) &&
         p->transport_mechanism == meshtastic_MeshPacket_TransportMechanism_TRANSPORT_LORA) {
         // cancel rebroadcast of this message *if* there was already one, unless we're a router/repeater!
         // But only LoRa packets should be able to trigger this.
diff --git a/src/mesh/FloodingRouter.h b/src/mesh/FloodingRouter.h
index 36c6ad8aa..68ba2a6e1 100644
--- a/src/mesh/FloodingRouter.h
+++ b/src/mesh/FloodingRouter.h
@@ -59,6 +59,9 @@ class FloodingRouter : public Router
      */
     virtual void sniffReceived(const meshtastic_MeshPacket *p, const meshtastic_Routing *c) override;
 
+    // Return false for roles like ROUTER or REPEATER which should always rebroadcast even when we've heard another rebroadcast of the same packet
+    bool roleAllowsCancelingDupe(const meshtastic_MeshPacket *p);
+
     /* Call when receiving a duplicate packet to check whether we should cancel a packet in the Tx queue */
     void perhapsCancelDupe(const meshtastic_MeshPacket *p);