Fix #739: fix #740: improve JoinAccept CFList processing

src/lmic/lmic.c

@@ -1621,21 +1621,9 @@ static bit_t processJoinAccept (void) {
     // initDefaultChannels(0) for EU-like, nothing otherwise
     LMICbandplan_joinAcceptChannelClear();
 
-    if (!LMICbandplan_hasJoinCFlist() && dlen > LEN_JA) {
-            // if no JoinCFList, we're supposed to continue
-            // the join per 2.2.5 of LoRaWAN regional 2.2.4
-            // https://github.com/mcci-catena/arduino-lmic/issues/19
-    } else if ( LMICbandplan_hasJoinCFlist() && dlen > LEN_JA ) {
-        dlen = OFF_CFLIST;
-        for( u1_t chidx=3; chidx<8; chidx++, dlen+=3 ) {
-            u4_t freq = LMICbandplan_convFreq(&LMIC.frame[dlen]);
-            if( freq ) {
-                LMIC_setupChannel(chidx, freq, 0, -1);
-#if LMIC_DEBUG_LEVEL > 1
-                LMIC_DEBUG_PRINTF("%"LMIC_PRId_ostime_t": Setup channel, idx=%d, freq=%"PRIu32"\n", os_getTime(), chidx, freq);
-#endif
-            }
-        }
+    // process the CFList if present
+    if (dlen == LEN_JAEXT) {
+        LMICbandplan_processJoinAcceptCFList();
     }
 
     // already incremented when JOIN REQ got sent off

src/lmic/lmic_bandplan.h

@@ -170,6 +170,10 @@
 # error "LMICbandplan_validDR() not defined by bandplan"
 #endif
 
+#if !defined(LMICbandplan_processJoinAcceptCFList)
+# error "LMICbandplan_processJoinAcceptCFList() not defined by bandplan"
+#endif
+
 //
 // Things common to lmic.c code
 //

src/lmic/lmic_eu_like.c

@@ -227,6 +227,27 @@ ostime_t LMICeulike_nextJoinState(uint8_t nDefaultChannels) {
 }
 #endif // !DISABLE_JOIN
 
+#if !defined(DISABLE_JOIN)
+void LMICeulike_processJoinAcceptCFList(void) {
+    if ( LMICbandplan_hasJoinCFlist() &&
+         LMIC.frame[OFF_CFLIST + 15] == LORAWAN_JoinAccept_CFListType_FREQUENCIES) {
+        u1_t dlen;
+        u1_t nDefault = LMIC_queryNumDefaultChannels();
+
+        dlen = OFF_CFLIST;
+        for( u1_t chidx = nDefault; chidx < nDefault + 5; chidx++, dlen+=3 ) {
+            u4_t freq = LMICbandplan_convFreq(&LMIC.frame[dlen]);
+            if( freq ) {
+                LMIC_setupChannel(chidx, freq, 0, -1);
+#if LMIC_DEBUG_LEVEL > 1
+                LMIC_DEBUG_PRINTF("%"LMIC_PRId_ostime_t": Setup channel, idx=%d, freq=%"PRIu32"\n", os_getTime(), chidx, freq);
+#endif
+            }
+        }
+    }
+}
+#endif // !DISABLE_JOIN
+
 void LMICeulike_saveAdrState(lmic_saved_adr_state_t *pStateBuffer) {
     os_copyMem(
             pStateBuffer->channelFreq,

src/lmic/lmic_eu_like.h

@@ -66,6 +66,11 @@ enum { BAND_MILLI = 0, BAND_CENTI = 1, BAND_DECI = 2, BAND_AUX = 3 };
 // there's a CFList on joins for EU-like plans
 #define LMICbandplan_hasJoinCFlist()    (1)
 
+/// \brief process CFLists from JoinAccept for EU-like regions
+void LMICeulike_processJoinAcceptCFList(void);
+/// \brief by default, EU-like plans use LMICeulike_processJoinAcceptCFList
+#define LMICbandplan_processJoinAcceptCFList    LMICeulike_processJoinAcceptCFList
+
 #define LMICbandplan_advanceBeaconChannel()     \
         do { /* nothing */ } while (0)
 

src/lmic/lmic_us_like.c

@@ -315,6 +315,32 @@ ostime_t LMICuslike_nextJoinState(void) {
 }
 #endif
 
+#if !defined(DISABLE_JOIN)
+void LMICuslike_processJoinAcceptCFList(void) {
+    if ( LMICbandplan_hasJoinCFlist() &&
+         LMIC.frame[OFF_CFLIST + 15] == LORAWAN_JoinAccept_CFListType_MASK ) {
+        u1_t dlen;
+
+        dlen = OFF_CFLIST;
+        for( u1_t chidx = 0; chidx < 8 * sizeof(LMIC.channelMap); chidx += 16, dlen += 2 ) {
+            u2_t mask = os_rlsbf2(&LMIC.frame[dlen]);
+#if LMIC_DEBUG_LEVEL > 1
+            LMIC_DEBUG_PRINTF("%"LMIC_PRId_ostime_t": Setup channel mask, group=%u, mask=%04x\n", os_getTime(), chidx, mask);
+#endif
+            for ( u1_t chnum = chidx; chnum < chidx + 16; ++chnum, mask >>= 1) {
+                if (chnum >= 72) {
+                    break;
+                } else if (mask & 1) {
+                    LMIC_enableChannel(chnum);
+                } else {
+                    LMIC_disableChannel(chnum);
+                }
+            }
+        }
+    }
+}
+#endif // !DISABLE_JOIN
+
 void LMICuslike_saveAdrState(lmic_saved_adr_state_t *pStateBuffer) {
         os_copyMem(
                 pStateBuffer->channelMap,

src/lmic/lmic_us_like.h

@@ -63,8 +63,14 @@ LMICuslike_isValidBeacon1(const uint8_t *d) {
 // provide a default LMICbandplan_joinAcceptChannelClear()
 #define LMICbandplan_joinAcceptChannelClear() do { } while (0)
 
-// no CFList on joins for US-like plans
-#define LMICbandplan_hasJoinCFlist()    (0)
+/// \brief there's a CFList on joins for US-like plans
+#define LMICbandplan_hasJoinCFlist()    (1)
+
+/// \brief process CFLists from JoinAccept for EU-like regions
+void LMICuslike_processJoinAcceptCFList(void);
+/// \brief by default, EU-like plans use LMICuslike_processJoinAcceptCFList
+#define LMICbandplan_processJoinAcceptCFList    LMICuslike_processJoinAcceptCFList
+
 
 #define LMICbandplan_advanceBeaconChannel()     \
         do { LMIC.bcnChnl = (LMIC.bcnChnl+1) & 7; } while (0)

src/lmic/lorabase.h

@@ -445,6 +445,13 @@ enum {
     LEN_JA          = 17,
     LEN_JAEXT       = 17+16
 };
+
+enum {
+    // JoinAccept CFList types
+    LORAWAN_JoinAccept_CFListType_FREQUENCIES = 0,  ///< the CFList contains 5 frequencies
+    LORAWAN_JoinAccept_CFListType_MASK = 1,         ///< the CFList contains channel-mask data
+};
+
 enum {
     // Data frame format
     OFF_DAT_HDR      = 0,