Fixes for Wi-SUN bbr behaviour

Learn prefix lifetimes and set them to addressess if changed in BBR
Fixed DHCP server initialize
Deleted dhcp server if address is removed
set address timeouts for BBR when address is removed

Author: Mika Tervonen

source/6LoWPAN/ws/ws_bbr_api.c

@@ -95,7 +95,6 @@ static void ws_bbr_rpl_root_start(uint8_t *dodag_id)
 
     rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, dodag_id, 64, t_flags, 0xffffffff, 0xffffffff, false);
     rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, dodag_id, 64, 0x18, 0xffffffff, false);
-    rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, NULL, 0, 0, 0xffffffff, false);
 }
 
 static void ws_bbr_rpl_root_stop(void)
@@ -242,9 +241,16 @@ static void ws_bbr_rpl_status_check(protocol_interface_info_entry_t *cur)
 
             rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, static_dodag_id, 64, PIO_A, 7200, 7200, false);
             rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, static_dodag_id, 64, 0x18, 7200, false);
-            rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, global_dodag_id, 64, 0, 7200, 0, true);
-            rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, global_dodag_id, 64, 0, 7200, true);
-            ipv6_route_add_with_info(global_dodag_id, 64, backbone_interface_id, NULL, ROUTE_THREAD_BBR, NULL, 0, 7200, 0);
+
+            // Old backbone information is deleted after 120 seconds
+            rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, NULL, 0, 0, 120, true);
+            rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, global_dodag_id, 64, 0, 120, 0, true);
+            rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, global_dodag_id, 64, 0, 120, true);
+            ipv6_route_add_with_info(global_dodag_id, 64, backbone_interface_id, NULL, ROUTE_THREAD_BBR, NULL, 0, 120, 0);
+            DHCPv6_server_service_delete(cur->id, global_dodag_id, false);
+
+            // Set old addresses to deferred and timeout
+            ws_dhcp_client_address_delete(cur, global_dodag_id);
         }
         // TODO add global prefix
         if (memcmp(global_id, ADDR_UNSPECIFIED,16) != 0) {
@@ -264,6 +270,7 @@ static void ws_bbr_rpl_status_check(protocol_interface_info_entry_t *cur)
             tr_info("RPL GUA activate %s", trace_ipv6(global_id));
             ws_dhcp_client_address_request(cur, global_id, ll);
 
+            rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, NULL, 0, 0, 7200, false);
             rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, static_dodag_id, 64, PIO_A, 7200, 0, false);
             rpl_control_update_dodag_route(protocol_6lowpan_rpl_root_dodag, static_dodag_id, 64, 0x18, 7200, false);
             rpl_control_update_dodag_prefix(protocol_6lowpan_rpl_root_dodag, global_id, 64, 0, 7200, 7200, false);

source/6LoWPAN/ws/ws_bootstrap.c

@@ -1581,6 +1581,11 @@ void ws_dhcp_client_address_request(protocol_interface_info_entry_t *cur, uint8_
     }
 }
 
+void ws_dhcp_client_address_delete(protocol_interface_info_entry_t *cur, uint8_t *prefix)
+{
+    dhcp_client_global_address_delete(cur->id, NULL, prefix);
+}
+
 static void ws_rpl_prefix_callback(prefix_entry_t *prefix, void *handle, uint8_t *parent_link_local)
 {
     protocol_interface_info_entry_t *cur = (protocol_interface_info_entry_t*) handle;
@@ -1593,8 +1598,22 @@ static void ws_rpl_prefix_callback(prefix_entry_t *prefix, void *handle, uint8_t
             ipv6_interface_slaac_handler(cur, prefix->prefix, prefix->prefix_len, prefix->lifetime, prefix->preftime);
         }
     } else if (prefix->prefix_len) {
-        ws_dhcp_client_address_request(cur, prefix->prefix, parent_link_local);
-    }
+        if (prefix->preftime == 0) {
+            // Delete all pending transactions from DHCP
+            // TODO this also deletes the address even when lifetime would allow it to be present
+            dhcp_client_global_address_delete(cur->id,NULL,prefix->prefix);
+        } else {
+            // Create new address using DHCP
+            ws_dhcp_client_address_request(cur, prefix->prefix, parent_link_local);
+        }
+        // If we have addresses generated we update the lifetimes always
+        ns_list_foreach(if_address_entry_t, entry, &cur->ip_addresses) {
+            if (entry->prefix_len == prefix->prefix_len && bitsequal(entry->address, prefix->prefix, prefix->prefix_len)) {
+                entry->preferred_lifetime = prefix->preftime;
+                entry->valid_lifetime = prefix->lifetime;
+            }
+        }
+     }
 }
 
 static void ws_bootstrap_rpl_activate(protocol_interface_info_entry_t *cur)

source/6LoWPAN/ws/ws_bootstrap.h

@@ -64,6 +64,8 @@ void ws_nud_active_timer(protocol_interface_info_entry_t *cur, uint16_t ticks);
 
 void ws_dhcp_client_address_request(protocol_interface_info_entry_t *cur, uint8_t *prefix, uint8_t *parent_link_local);
 
+void ws_dhcp_client_address_delete(protocol_interface_info_entry_t *cur, uint8_t *prefix);
+
 #else
 
 #define ws_bootstrap_init(interface_id, bootstrap_mode) (-1)

source/DHCPv6_Server/DHCPv6_Server_service.c

@@ -236,28 +236,21 @@ int DHCPv6_server_service_init(int8_t interface, uint8_t guaPrefix[static 16], u
     //allocate Socket Service
     socketInstance  = dhcp_service_init(interface, DHCP_INSTANCE_SERVER, DHCPV6_server_service_request_handler);
     cur = protocol_stack_interface_info_get_by_id(interface);
-    if (cur) {
-        if (dhcpv6_server_service_tasklet_generated() < 0) {
-            retVal = -2;
-        } else if (!DHCP_server_service_timer_start()) {
-            retVal = -2;
-        } else {
-            //allocate server
-            dhcpv6_gua_server_entry_s *serverInfo = libdhcpv6_gua_server_allocate(guaPrefix, interface, cur->mac, DHCPV6_DUID_HARDWARE_EUI64_TYPE);
-            if (serverInfo) {
-                //if_address_entry_t *def_address = NULL;
-                uint8_t temp[16];
-                uint8_t *ptr = temp;
-                //define address & Route advert's
-                memcpy(ptr, guaPrefix, 8);
-                ptr += 8;
-                memcpy(ptr, cur->iid_slaac, 8);
-
-                serverInfo->socketInstance_id = socketInstance;
-                socketInstance = 0;
-                //Generate Address for current interface
-                retVal = 0;
-            }
+    if (!cur) {
+        return -1;
+    }
+
+    if (dhcpv6_server_service_tasklet_generated() < 0) {
+        retVal = -2;
+    } else if (!DHCP_server_service_timer_start()) {
+        retVal = -2;
+    } else {
+        //allocate server
+        dhcpv6_gua_server_entry_s *serverInfo = libdhcpv6_gua_server_allocate(guaPrefix, interface, cur->mac, DHCPV6_DUID_HARDWARE_EUI64_TYPE);
+        if (serverInfo) {
+            serverInfo->socketInstance_id = socketInstance;
+            socketInstance = 0;
+            retVal = 0;
         }
     }
     if (socketInstance > 0) {

source/libDHCPv6/libDHCPv6_server.c

@@ -142,8 +142,8 @@ dhcpv6_gua_server_entry_s *libdhcpv6_server_data_get_by_prefix_and_socketinstanc
 
 dhcpv6_gua_server_entry_s *libdhcpv6_gua_server_allocate(uint8_t *prefix, int8_t interfaceId, uint8_t *serverDUID, uint16_t serverDUIDType)
 {
-    dhcpv6_gua_server_entry_s *entry = NULL;
-    if (libdhcpv6_server_data_get_by_prefix_and_interfaceid(interfaceId, prefix) == NULL) {
+    dhcpv6_gua_server_entry_s *entry = libdhcpv6_server_data_get_by_prefix_and_interfaceid(interfaceId, prefix);
+    if (entry == NULL) {
         entry = libdhcpv6_server_entry_allocate();
         if (entry) {
             memcpy(entry->guaPrefix, prefix, 8);