Wi-SUN bootstrap support RPL poison from Connected state to Discovery

From Connected State to discovery will now do Soft RPL down by new state.
State is started by trigger RPL poison and wait event from RPL before trigger
discovery state.

Author: Juha Heiuskanen

source/6LoWPAN/ws/ws_bootstrap.c

@@ -1086,6 +1086,32 @@ static int8_t ws_bootstrap_up(protocol_interface_info_entry_t *cur)
     return ret_val;
 }
 
+void ws_bootstrap_disconnect(protocol_interface_info_entry_t *cur, ws_bootsrap_event_type_e event_type)
+{
+    if (cur->nwk_bootstrap_state == ER_RPL_NETWORK_LEAVING) {
+        //Already moved to leaving state.
+        return;
+    }
+
+    if (cur->rpl_domain && cur->nwk_bootstrap_state == ER_BOOTSRAP_DONE) {
+        //Stop Asych Timer
+        ws_bootstrap_asynch_trickle_stop(cur);
+        tr_debug("Start Network soft leaving");
+        if (event_type == WS_FAST_DISCONNECT) {
+            rpl_control_instant_poison(cur, cur->rpl_domain);
+            cur->bootsrap_state_machine_cnt = 80; //Give 8 seconds time to send Poison
+        } else {
+            rpl_control_poison(cur->rpl_domain, 1);
+            cur->bootsrap_state_machine_cnt = 6000; //Give 10 minutes time for poison if RPL is not report
+        }
+
+    } else {
+        ws_bootstrap_event_discovery_start(cur);
+    }
+    cur->nwk_bootstrap_state = ER_RPL_NETWORK_LEAVING;
+}
+
+
 static void ws_bootstrap_asynch_trickle_stop(protocol_interface_info_entry_t *cur)
 {
     cur->ws_info->trickle_pas_running = false;
@@ -1638,7 +1664,7 @@ static void ws_bootstrap_pan_config_analyse(struct protocol_interface_info_entry
                 tr_debug("NEW Brodcast Schedule %u...BR rebooted", ws_bs_ie.broadcast_schedule_identifier);
                 cur->ws_info->ws_bsi_block.block_time = cur->ws_info->cfg->timing.pan_timeout;
                 cur->ws_info->ws_bsi_block.old_bsi = cur->ws_info->hopping_schdule.fhss_bsi;
-                ws_bootstrap_event_discovery_start(cur);
+                ws_bootstrap_event_disconnect(cur, WS_NORMAL_DISCONNECT);
             }
             return;
         }
@@ -2553,6 +2579,15 @@ static void ws_bootstrap_rpl_callback(rpl_event_t event, void *handle)
     if (!cur->rpl_domain || cur->interface_mode != INTERFACE_UP) {
         return;
     }
+
+    if (event == RPL_EVENT_POISON_FINISHED) {
+        //If we are waiting poison we will trig Discovery after couple seconds
+        if (cur->nwk_bootstrap_state == ER_RPL_NETWORK_LEAVING) {
+            cur->bootsrap_state_machine_cnt = 80; //Give 8 seconds time to send Poison
+        }
+        return;
+    }
+
     // if waiting for RPL and
     if (event == RPL_EVENT_DAO_DONE) {
         // Trigger statemachine check
@@ -3132,6 +3167,12 @@ void ws_bootstrap_event_routing_ready(protocol_interface_info_entry_t *cur)
 {
     ws_bootsrap_event_trig(WS_ROUTING_READY, cur->bootStrapId, ARM_LIB_LOW_PRIORITY_EVENT, NULL);
 }
+
+void ws_bootstrap_event_disconnect(protocol_interface_info_entry_t *cur, ws_bootsrap_event_type_e event_type)
+{
+    ws_bootsrap_event_trig(event_type, cur->bootStrapId, ARM_LIB_LOW_PRIORITY_EVENT, NULL);
+}
+
 void ws_bootstrap_configuration_trickle_reset(protocol_interface_info_entry_t *cur)
 {
     trickle_inconsistent_heard(&cur->ws_info->trickle_pan_config, &cur->ws_info->trickle_params_pan_discovery);
@@ -3315,6 +3356,7 @@ static int8_t ws_bootstrap_backbone_ip_addr_get(protocol_interface_info_entry_t
     return -1;
 }
 
+
 static void ws_bootstrap_event_handler(arm_event_s *event)
 {
     ws_bootsrap_event_type_e event_type;
@@ -3331,7 +3373,6 @@ static void ws_bootstrap_event_handler(arm_event_s *event)
             break;
         case WS_DISCOVERY_START:
             tr_info("Discovery start");
-
             protocol_mac_reset(cur);
             ws_llc_reset(cur);
             lowpan_adaptation_interface_reset(cur->id);
@@ -3467,6 +3508,12 @@ static void ws_bootstrap_event_handler(arm_event_s *event)
             ws_bootstrap_advertise_start(cur);
             ws_bootstrap_state_change(cur, ER_BOOTSRAP_DONE);
             break;
+        case WS_FAST_DISCONNECT:
+            ws_bootstrap_disconnect(cur, WS_FAST_DISCONNECT);
+            break;
+        case WS_NORMAL_DISCONNECT:
+            ws_bootstrap_disconnect(cur, WS_NORMAL_DISCONNECT);
+            break;
 
         default:
             tr_err("Invalid event received");
@@ -3658,6 +3705,10 @@ void ws_bootstrap_state_machine(protocol_interface_info_entry_t *cur)
             // Bootstrap_done event to application
             nwk_bootsrap_state_update(ARM_NWK_BOOTSTRAP_READY, cur);
             break;
+        case ER_RPL_NETWORK_LEAVING:
+            tr_debug("WS SM:RPL Leaving ready trigger discovery");
+            ws_bootstrap_event_discovery_start(cur);
+            break;
         default:
             tr_warn("WS SM:Invalid state %d", cur->nwk_bootstrap_state);
     }
@@ -3743,9 +3794,10 @@ void ws_bootstrap_seconds_timer(protocol_interface_info_entry_t *cur, uint32_t s
             }
         } else {
             // Border router has timed out
+            //Clear Timeout timer
             cur->ws_info->pan_timeout_timer = 0;
             tr_warn("Border router has timed out");
-            ws_bootstrap_event_discovery_start(cur);
+            ws_bootstrap_event_disconnect(cur, WS_FAST_DISCONNECT);
         }
     }
     if (cur->ws_info->aro_registration_timer) {

source/6LoWPAN/ws/ws_bootstrap.h

@@ -24,7 +24,9 @@ typedef enum {
     WS_DISCOVERY_START,      /**< discovery start*/
     WS_CONFIGURATION_START,  /**< configuration learn start*/
     WS_OPERATION_START,      /**< active operation start*/
-    WS_ROUTING_READY        /**< RPL routing connected to BR*/
+    WS_ROUTING_READY,        /**< RPL routing connected to BR*/
+    WS_FAST_DISCONNECT,      /**< Do fast timeout after Border router timeout*/
+    WS_NORMAL_DISCONNECT     /**< Border have been rebooted so Slow poison Process*/
 } ws_bootsrap_event_type_e;
 
 #ifdef HAVE_WS
@@ -60,6 +62,8 @@ void ws_bootstrap_event_operation_start(protocol_interface_info_entry_t *cur);
 
 void ws_bootstrap_event_routing_ready(protocol_interface_info_entry_t *cur);
 
+void ws_bootstrap_event_disconnect(protocol_interface_info_entry_t *cur, ws_bootsrap_event_type_e event_type);
+
 void ws_bootstrap_configuration_trickle_reset(protocol_interface_info_entry_t *cur);
 
 void ws_bootstrap_seconds_timer(protocol_interface_info_entry_t *cur, uint32_t seconds);

source/NWK_INTERFACE/Include/protocol.h

@@ -124,6 +124,7 @@ typedef enum icmp_state {
     ER_BOOTSTRAP_NEW_FRAGMENT_START,
     ER_WAIT_RESTART,
     ER_RPL_LOCAL_REPAIR,
+    ER_RPL_NETWORK_LEAVING,
 } icmp_state_t;
 
 typedef enum {