Detection of duplicate address entries updated (#1686)

Author: deepakvenugopal

source/6LoWPAN/Thread/thread_extension_bbr.c

@@ -91,6 +91,7 @@ typedef struct {
     uint8_t ml_eid[8];
     uint8_t target_eid[16];
     uint16_t ttl;
+    uint8_t dua_dad_repeat;
     ns_list_link_t link;
 } duplicate_dua_tr_t;
 
@@ -101,6 +102,8 @@ static NS_LIST_DEFINE(duplicate_dua_tr_list, duplicate_dua_tr_t, link);
 #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_DAD_QUERY_TIMEOUT          1     // wait period for Duplicate Address Detection
+#define THREAD_BBR_DUA_DAD_REPEATS                2     // multicast repeated as part of DUA
 
 /*
 0 – Successful registration
@@ -164,7 +167,8 @@ static duplicate_dua_tr_t *thread_border_router_dup_tr_create(int8_t interface_i
     memcpy(this->target_eid, target_eid_ptr,16);
     memcpy(this->source_address, source_addr_ptr, 16);
     memcpy(this->ml_eid, ml_eid_ptr,8);
-    this->ttl = 2;
+    this->dua_dad_repeat = THREAD_BBR_DUA_DAD_REPEATS;
+    this->ttl = THREAD_BBR_DUA_DAD_QUERY_TIMEOUT;
     return this;
 }
 
@@ -1062,6 +1066,31 @@ bool thread_extension_bbr_nd_query_process(protocol_interface_info_entry_t *cur,
 
 }
 
+static void thread_extension_bbr_dad_process(protocol_interface_info_entry_t *cur, thread_pbbr_t *this, uint32_t seconds)
+{
+    ns_list_foreach_safe(duplicate_dua_tr_t, cur_dup_tr, &duplicate_dua_tr_list) {
+        if (cur_dup_tr->interface_id != cur->id) {
+            continue;
+        }
+        if (cur_dup_tr->ttl > seconds) {
+            cur_dup_tr->ttl -= seconds;
+        } else {
+            cur_dup_tr->dua_dad_repeat--;
+            // repeat dad for one more time
+            if (cur_dup_tr->dua_dad_repeat > 0) {
+                cur_dup_tr->ttl = THREAD_BBR_DUA_DAD_QUERY_TIMEOUT;
+                thread_border_router_bb_qry_send(this,cur_dup_tr->target_eid,NULL);
+                return;
+            } else {
+                // dad completed
+                // send PRO_BB.ntf and delete dad entry
+                thread_border_router_bb_ans_send(this, this->pbbr_multicast_address, cur_dup_tr->target_eid, cur_dup_tr->ml_eid, 0, thread_joiner_application_network_name_get(cur->id), NULL);
+                thread_border_router_dup_tr_delete(cur_dup_tr);
+            }
+        }
+    }
+}
+
 void thread_extension_bbr_route_update(protocol_interface_info_entry_t *cur)
 {
     // if we have DUA prefix in settings
@@ -1095,6 +1124,7 @@ void thread_extension_bbr_route_update(protocol_interface_info_entry_t *cur)
     }
 }
 
+
 void thread_extension_bbr_seconds_timer(int8_t interface_id, uint32_t seconds)
 {
     thread_pbbr_t *this = thread_bbr_find_by_interface(interface_id);
@@ -1146,15 +1176,8 @@ void thread_extension_bbr_seconds_timer(int8_t interface_id, uint32_t seconds)
     // Check secondary state if we need to drop
 
     // Check pending dua registrations
-    ns_list_foreach_safe(duplicate_dua_tr_t, cur_dup_tr, &duplicate_dua_tr_list) {
-        if (cur_dup_tr->interface_id == interface_id && cur_dup_tr->ttl > seconds) {
-            cur_dup_tr->ttl -= seconds;
-            // TODO Repeat the ANS 2 times.
-        } else {
-            // Timeout Remmove the duplicate detection timer
-            thread_border_router_dup_tr_delete(cur_dup_tr);
-        }
-    }
+    thread_extension_bbr_dad_process(cur, this, seconds);
+
     if (this->dua_timer_ticks) {
         if (this->dua_timer_ticks > seconds) {
             this->dua_timer_ticks -= seconds;

source/6LoWPAN/Thread/thread_joiner_application.c

@@ -917,6 +917,15 @@ link_configuration_s *thread_joiner_application_get_config(int8_t interface_id)
     return this->configuration_ptr;
 }
 
+uint8_t *thread_joiner_application_network_name_get(int8_t interface_id)
+{
+    thread_joiner_t *this = thread_joiner_find(interface_id);
+    if (!this) {
+        return NULL;
+    }
+    return this->configuration_ptr->name;
+}
+
 static int thread_joiner_application_nvm_link_config_read(thread_joiner_t *this) {
 
     // read config from NVM, in case of failure current settings are unchanged.

source/6LoWPAN/Thread/thread_joiner_application.h

@@ -69,6 +69,7 @@ struct link_configuration *thread_joiner_application_get_config(int8_t interface
 uint64_t thread_joiner_application_active_timestamp_get(int8_t interface_id);
 uint8_t thread_joiner_application_security_policy_get(int8_t interface_id);
 void thread_joiner_application_active_timestamp_set(int8_t interface_id, uint64_t timestamp);
+uint8_t *thread_joiner_application_network_name_get(int8_t interface_id);
 uint8_t *thread_joiner_application_active_config_tlv_list_get(uint8_t interface_id, uint16_t *length);
 
 uint8_t *thread_joiner_application_active_config_params_get(uint8_t interface_id, uint16_t *length);