Detect border router connection lost

reset stack and go to discovery when lost connection to Border router

Author: Mika Tervonen

source/6LoWPAN/ws/ws_bootstrap.c

@@ -43,6 +43,7 @@
 #include "RPL/rpl_data.h"
 #include "Common_Protocols/icmpv6.h"
 #include "Common_Protocols/icmpv6_radv.h"
+#include "Common_Protocols/ipv6_constants.h"
 #include "6LoWPAN/ws/ws_common_defines.h"
 #include "Service_Libs/Trickle/trickle.h"
 #include "6LoWPAN/ws/ws_common_defines.h"
@@ -854,14 +855,34 @@ static void ws_bootstrap_network_configuration_learn(protocol_interface_info_ent
     return;
 }
 
+static void ws_bootstrap_ip_stack_addr_clear(protocol_interface_info_entry_t *cur)
+{
+    tr_debug("ip stack address clear");
+    ns_list_foreach_safe(if_address_entry_t, addr, &cur->ip_addresses) {
+        if (addr->source != ADDR_SOURCE_STATIC &&
+                addr_ipv6_scope(addr->address,cur) > IPV6_SCOPE_LINK_LOCAL) {
+            // Remove all exept User set address
+            addr_delete_entry(cur, addr);
+        }
+    }
+}
+
+static void ws_bootstrap_ip_stack_reset(protocol_interface_info_entry_t *cur)
+{
+    tr_debug("ip stack reset");
+    // Delete all temporary cached information
+    ipv6_neighbour_cache_flush(&cur->ipv6_neighbour_cache);
+    lowpan_context_list_free(&cur->lowpan_contexts);
+}
+
 static void ws_bootstrap_ip_stack_activate(protocol_interface_info_entry_t *cur)
 {
     tr_debug("ip stack init");
     clear_power_state(ICMP_ACTIVE);
     cur->lowpan_info |= INTERFACE_NWK_BOOTSRAP_ACTIVE;
-    ipv6_neighbour_cache_flush(&cur->ipv6_neighbour_cache);
-
+    ws_bootstrap_ip_stack_reset(cur);
 }
+
 static void ws_bootstrap_rpl_callback(rpl_event_t event, void *handle)
 {
 
@@ -874,12 +895,13 @@ static void ws_bootstrap_rpl_callback(rpl_event_t event, void *handle)
         // Trigger statemachine check
         cur->bootsrap_state_machine_cnt = 1;
     } else if(event == RPL_EVENT_LOCAL_REPAIR_NO_MORE_DIS) {
-        // RPL gave up so we need to re-trigger network scan.
-        // TODO is this correct?
-        // TODO no! ws_bootstrap_event_configuration_start(cur); causes failure to
-        // We could send solicit for configuration and then select new parent when those arrive
-        /* This is done after address deletion, so RPL can act on them */
-        ws_bootstrap_event_configuration_start(cur);
+        /*
+         * RPL goes to passive mode, but does not require any extra changed
+         *
+         * We could remove our current addresses learned from RPL
+         * We could send solicit for configuration and then select new parent when those arrive
+         *
+         */
 
     }
     cur->ws_info->rpl_state = event;
@@ -900,6 +922,7 @@ static void ws_bootstrap_rpl_activate(protocol_interface_info_entry_t *cur)
 
     cur->ws_info->rpl_state = 0xff; // Set invalid state and learn from event
     if (cur->bootsrap_mode == ARM_NWK_BOOTSRAP_MODE_6LoWPAN_ROUTER) {
+        // TODO RPL should have function to reset DIS trickle and it should be called here
         rpl_control_transmit_dis(cur->rpl_domain, cur, 0, 0, NULL, 0, ADDR_LINK_LOCAL_ALL_RPL_NODES);
     }
 }
@@ -940,6 +963,14 @@ static void ws_bootstrap_start_discovery(protocol_interface_info_entry_t *cur)
     // Clear learned neighbours
     ws_bootstrap_neighbor_list_clean(cur);
 
+    // Clear RPL information
+    rpl_control_remove_domain_from_interface(cur);
+
+    // Clear ip stack from old information
+    ws_bootstrap_ip_stack_reset(cur);
+    // New network scan started old addresses not assumed valid anymore
+    ws_bootstrap_ip_stack_addr_clear(cur);
+
     // Reset advertisement solicit trickle to start discovering network
     trickle_start(&cur->ws_info->trickle_pan_advertisement_solicit, &trickle_params_pan_configuration);
     trickle_inconsistent_heard(&cur->ws_info->trickle_pan_advertisement_solicit, &trickle_params_pan_configuration);
@@ -952,20 +983,18 @@ static void ws_bootstrap_start_configuration_learn(protocol_interface_info_entry
     ws_bootstrap_state_change(cur, ER_SCAN);
 
     cur->ws_info->configuration_learned = false;
-    cur->ws_info->pan_version_timeout_timer = 0;
-    rpl_control_remove_domain_from_interface(cur);
-    ipv6_neighbour_cache_flush(&cur->ipv6_neighbour_cache);
     // Clear parent info
     memset(cur->ws_info->parent_info.addr,0,8);
 
+    // Clear all temporary information
+    ws_bootstrap_ip_stack_reset(cur);
+
     // Clear learned neighbours
     ws_bootstrap_neighbor_list_clean(cur);
 
     // Reset advertisement solicit trickle to start discovering network
     trickle_start(&cur->ws_info->trickle_pan_config_solicit, &trickle_params_pan_configuration);
     trickle_inconsistent_heard(&cur->ws_info->trickle_pan_config_solicit, &trickle_params_pan_configuration);
-
-
 }
 
 /*