From 616fff15c39b0b2029d82f9e2fc33d8ad837bcc1 Mon Sep 17 00:00:00 2001
From: StevenCellist <steven@boonstoppel.nu>
Date: Sat, 18 May 2024 13:10:37 +0200
Subject: [PATCH] [LoRaWAN] Fix rejoining during active session

---
 keywords.txt                      |  1 -
 src/protocols/LoRaWAN/LoRaWAN.cpp | 21 ++++++++++++++++-----
 src/protocols/LoRaWAN/LoRaWAN.h   | 12 ++++++------
 3 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/keywords.txt b/keywords.txt
index 9f5c89b3..13755586 100644
--- a/keywords.txt
+++ b/keywords.txt
@@ -313,7 +313,6 @@ checkDataRate	KEYWORD2
 setModem	KEYWORD2
 
 # LoRaWAN
-wipe	KEYWORD2
 getBufferNonces	KEYWORD2
 setBufferNonces	KEYWORD2
 getBufferSession	KEYWORD2
diff --git a/src/protocols/LoRaWAN/LoRaWAN.cpp b/src/protocols/LoRaWAN/LoRaWAN.cpp
index 0aa3aba1..e2d75130 100644
--- a/src/protocols/LoRaWAN/LoRaWAN.cpp
+++ b/src/protocols/LoRaWAN/LoRaWAN.cpp
@@ -44,13 +44,19 @@ void LoRaWANNode::setCSMA(uint8_t backoffMax, uint8_t difsSlots, bool enableCSMA
     this->enableCSMA = enableCSMA;
 }
 
-void LoRaWANNode::wipe() {
+void LoRaWANNode::clearNonces() {
+  // clear & set all the device credentials
   memset(this->bufferNonces, 0, RADIOLIB_LW_NONCES_BUF_SIZE);
+  this->keyCheckSum = 0;
+  this->devNonce = 0;
+  this->joinNonce = 0;
+  this->isActive = false;
+}
+
+void LoRaWANNode::clearSession() {
   memset(this->bufferSession, 0, RADIOLIB_LW_SESSION_BUF_SIZE);
   memset(&(this->commandsUp), 0, sizeof(LoRaWANMacCommandQueue_t));
   memset(&(this->commandsDown), 0, sizeof(LoRaWANMacCommandQueue_t));
-  this->devNonce = 0;
-  this->joinNonce = 0;
 }
 
 uint8_t* LoRaWANNode::getBufferNonces() {
@@ -445,6 +451,7 @@ void LoRaWANNode::beginOTAA(uint64_t joinEUI, uint64_t devEUI, uint8_t* nwkKey,
   this->keyCheckSum ^= LoRaWANNode::checkSum16(nwkKey, 16);
   this->keyCheckSum ^= LoRaWANNode::checkSum16(appKey, 16);
 
+  this->clearNonces();
   this->lwMode = RADIOLIB_LW_MODE_OTAA;
   this->lwClass = RADIOLIB_LW_CLASS_A;
 }
@@ -465,7 +472,8 @@ int16_t LoRaWANNode::activateOTAA(bool force, uint8_t joinDr, LoRaWANJoinEvent_t
 
   int16_t state = RADIOLIB_ERR_UNKNOWN;
   
-  // either no valid session was found or user forced a new session, so set active-bit to false
+  // either no valid session was found or user forced a new session, so clear all activity
+  this->clearSession();
   this->bufferNonces[RADIOLIB_LW_NONCES_ACTIVE] = (uint8_t)false;
   this->isActive = false;
 
@@ -764,6 +772,8 @@ void LoRaWANNode::beginABP(uint32_t addr, uint8_t* fNwkSIntKey, uint8_t* sNwkSIn
   if(fNwkSIntKey) { this->keyCheckSum ^= LoRaWANNode::checkSum16(fNwkSIntKey, 16); }
   if(sNwkSIntKey) { this->keyCheckSum ^= LoRaWANNode::checkSum16(sNwkSIntKey, 16); }
 
+  // clear & set all the device credentials
+  this->clearNonces();
   this->lwMode = RADIOLIB_LW_MODE_ABP;
   this->lwClass = RADIOLIB_LW_CLASS_A;
 }
@@ -782,7 +792,8 @@ int16_t LoRaWANNode::activateABP(bool force, uint8_t initialDr) {
     }
   }
 
-  // either no valid session was found or user forced a new session, so set active-bit to false
+  // either no valid session was found or user forced a new session, so clear all activity
+  this->clearSession();
   this->bufferNonces[RADIOLIB_LW_NONCES_ACTIVE] = (uint8_t)false;
   this->isActive = false;
 
diff --git a/src/protocols/LoRaWAN/LoRaWAN.h b/src/protocols/LoRaWAN/LoRaWAN.h
index 025a58ec..18f42367 100644
--- a/src/protocols/LoRaWAN/LoRaWAN.h
+++ b/src/protocols/LoRaWAN/LoRaWAN.h
@@ -527,12 +527,6 @@ class LoRaWANNode {
     */
     LoRaWANNode(PhysicalLayer* phy, const LoRaWANBand_t* band, uint8_t subBand = 0);
 
-    /*!
-      \brief Wipe internal persistent parameters.
-      This will reset all counters and saved variables, so the device will have to rejoin the network.
-    */
-    void wipe();
-
     /*!
       \brief Returns the pointer to the internal buffer that holds the LW base parameters
       \returns Pointer to uint8_t array of size RADIOLIB_LW_NONCES_BUF_SIZE
@@ -981,6 +975,12 @@ class LoRaWANNode {
     // save the selected sub-band in case this must be restored in ADR control
     uint8_t subBand = 0;
 
+    // this will reset the device credentials, so the device starts completely new
+    void clearNonces();
+
+    // this will reset all counters and saved variables, so the device will have to rejoin the network.
+    void clearSession();
+
     // wait for, open and listen during Rx1 and Rx2 windows; only performs listening
     int16_t downlinkCommon();