Multicast registration time fix (#1631)

Fix for multicast registration timeouts.

Author: Tero Heinonen

source/6LoWPAN/Thread/thread_constants.h

@@ -164,7 +164,7 @@
 
 #define THREAD_ENTERPRISE_NUMBER 44970
 
-#define THREAD_ADDR_REG_TIMEOUT_BASE 300
+#define THREAD_ADDR_REG_RETRY_INTERVAL 300
 #define THREAD_PROACTIVE_AN_INTERVAL 3600
 
 // Router defines

source/6LoWPAN/Thread/thread_extension.c

@@ -271,6 +271,9 @@ int thread_extension_primary_bbr_get(struct protocol_interface_info_entry *cur,
                       }
                       if (mlr_timer_ptr) {
                           *mlr_timer_ptr = common_read_32_bit(&found_tlv[7]);
+                          if (*mlr_timer_ptr < THREAD_DEFAULT_MIN_MLR_TIMEOUT) {
+                              *mlr_timer_ptr = THREAD_DEFAULT_MIN_MLR_TIMEOUT;
+                          }
                       }
                       return 0;
                   }
@@ -496,14 +499,16 @@ void thread_extension_mcast_subscrition_change(protocol_interface_info_entry_t *
     if (addr_ipv6_multicast_scope(group->group) < IPV6_SCOPE_ADMIN_LOCAL) {
         return;
     }
-    // Default timer added.
-    group->mld_timer = added ? THREAD_ADDR_REG_TIMEOUT_BASE + randLIB_get_random_in_range(1, 30) : 0;
 
-    if (0 !=thread_extension_primary_bbr_get(interface, br_ml_addr, NULL, &mlr_timer, NULL )) {
+    if (0 != thread_extension_primary_bbr_get(interface, br_ml_addr, NULL, &mlr_timer, NULL )) {
+        // No BBR, try again later if adding address.
+        group->mld_timer = added ? THREAD_ADDR_REG_RETRY_INTERVAL + randLIB_get_random_in_range(1, 30) : 0;
         return;
     }
-    // follow the Primary BBR set timeout + Small jitter added
-    group->mld_timer = added ? mlr_timer: 0;
+
+    // follow the Primary BBR set timeout.
+    group->mld_timer = added ? (mlr_timer - randLIB_get_random_in_range(30, 40)) : 0;
+
     // MLR is sent only for primary BBR for now, but this might change
     thread_extension_mlr_req_send(interface, br_ml_addr, group->group);
 

source/6LoWPAN/Thread/thread_extension_bbr.c

@@ -98,11 +98,10 @@ typedef struct {
 static NS_LIST_DEFINE(pbbr_instance_list, thread_pbbr_t, link);
 static NS_LIST_DEFINE(duplicate_dua_tr_list, duplicate_dua_tr_t, link);
 
-
-#define THREAD_BBR_MLR_REGISTRATION_TIMEOUT       120
+#define THREAD_BBR_MLR_REGISTRATION_TIMEOUT       600   //<* Default MLR timeout in seconds
 #define THREAD_BBR_DUA_REGISTRATION_TIMEOUT       3600
-#define THREAD_BBR_DUA_REGISTRATION_DELAY         5000 // 5 seconds in ms
-#define THREAD_BBR_BACKBONE_PORT                 5683  //<* Backbone border router
+#define THREAD_BBR_DUA_REGISTRATION_DELAY         5000  // 5 seconds in ms
+#define THREAD_BBR_BACKBONE_PORT                  5683  //<* Backbone border router
 
 /*
 0 – Successful registration
@@ -608,8 +607,9 @@ static int thread_extension_bbr_mlr_cb(int8_t service_id, uint8_t source_address
         bbr_status = THREAD_BBR_STATUS_NOT_PRIMARY_BBR;
         goto send_response;
     }
+
+    //check if commissioner
     if (2 <= thread_meshcop_tlv_data_get_uint16(request_ptr->payload_ptr, request_ptr->payload_len, MESHCOP_TLV_COMMISSIONER_SESSION_ID, &session_id)) {
-        //check if commissioner
         // Session id present must be valid
         tr_info("message from commissioner");
         if (cur->thread_info->registered_commissioner.session_id != session_id) {
@@ -630,8 +630,10 @@ static int thread_extension_bbr_mlr_cb(int8_t service_id, uint8_t source_address
         response_code = COAP_MSG_CODE_RESPONSE_BAD_REQUEST;
         goto send_response;
     }
+
     int16_t remaining = addr_len;
     uint8_t *addr_ptr = addr_data_ptr;
+
     while (remaining > 0) {
         //Go through all addresses
         if (timeout_value == 0) {

source/6LoWPAN/Thread/thread_extension_constants.h

@@ -38,6 +38,11 @@ typedef struct discovery_additional_info {
     bool ccm_supported:1;
 }discovery_additional_info_t;
 
+/**
+ * Minimum specified MLR timeout in seconds
+ */
+#define THREAD_DEFAULT_MIN_MLR_TIMEOUT 300
+
 /**
  * Default Autonomous enrollment port.
   */