link-local multicast group registration (ARMmbed#1880)

Added possibility for rx-off-when idle devices to register link-local multicast groups to parent.

Author: deepakvenugopal

source/6LoWPAN/Thread/thread_common.c

@@ -1746,6 +1746,7 @@ bool thread_addresses_needs_to_be_registered(protocol_interface_info_entry_t *cu
 {
     lowpan_context_t *ctx;
     uint8_t thread_realm_local_mcast_addr[16];
+    uint8_t thread_ll_unicast_prefix_based_mcast_addr[16];
     if (thread_info(cur)->thread_device_mode != THREAD_DEVICE_MODE_SLEEPY_END_DEVICE &&
             thread_info(cur)->thread_device_mode != THREAD_DEVICE_MODE_END_DEVICE) {
         // No address registration for others than MED or SED
@@ -1768,18 +1769,22 @@ bool thread_addresses_needs_to_be_registered(protocol_interface_info_entry_t *cu
     }
 
     // check for multicast groups
-    thread_bootstrap_all_nodes_address_generate(thread_realm_local_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, 3);
+    thread_bootstrap_all_nodes_address_generate(thread_realm_local_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, IPV6_SCOPE_REALM_LOCAL);
+    thread_bootstrap_all_nodes_address_generate(thread_ll_unicast_prefix_based_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, IPV6_SCOPE_LINK_LOCAL);
     ns_list_foreach(if_group_entry_t, entry, &cur->ip_groups)
     {
-        if (addr_ipv6_multicast_scope(entry->group) < IPV6_SCOPE_REALM_LOCAL) {
-            /* Skip Link Local multicast address */
+        if (!memcmp((entry->group), ADDR_MULTICAST_SOLICITED, 13)) {
+            /* Skip solicited node multicast address */
             continue;
         }
-
         if (addr_ipv6_equal(entry->group, thread_realm_local_mcast_addr)) {
             /* Skip well-known realm-local all Thread nodes multicast address */
             continue;
         }
+        if (addr_ipv6_equal(entry->group, thread_ll_unicast_prefix_based_mcast_addr)) {
+            /* Skip well-known link-local all Thread nodes multicast address */
+            continue;
+        }
         if (addr_ipv6_equal(entry->group, ADDR_ALL_MPL_FORWARDERS)) {
             /* Skip All MPL Forwarders address */
             continue;
@@ -1835,6 +1840,7 @@ uint8_t *thread_ml_address_tlv_write(uint8_t *ptr, protocol_interface_info_entry
 uint8_t *thread_address_registration_tlv_write(uint8_t *ptr, protocol_interface_info_entry_t *cur)
 {
     uint8_t thread_realm_local_mcast_addr[16];
+    uint8_t thread_ll_unicast_prefix_based_mcast_addr[16];
     lowpan_context_t *ctx;
     uint8_t *address_len_ptr;
 
@@ -1850,7 +1856,6 @@ uint8_t *thread_address_registration_tlv_write(uint8_t *ptr, protocol_interface_
 
     // Register all global addressess
     ns_list_foreach(if_address_entry_t, e, &cur->ip_addresses) {
-
         if (*address_len_ptr > 148 ) {
             // Maximum length of address registrations
             continue;
@@ -1874,23 +1879,27 @@ uint8_t *thread_address_registration_tlv_write(uint8_t *ptr, protocol_interface_
     }
 
     /* Registers multicast addresses to the parent */
-    thread_bootstrap_all_nodes_address_generate(thread_realm_local_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, 3);
-
+    thread_bootstrap_all_nodes_address_generate(thread_realm_local_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, IPV6_SCOPE_REALM_LOCAL);
+    thread_bootstrap_all_nodes_address_generate(thread_ll_unicast_prefix_based_mcast_addr, cur->thread_info->threadPrivatePrefixInfo.ulaPrefix, IPV6_SCOPE_LINK_LOCAL);
     ns_list_foreach(if_group_entry_t, entry, &cur->ip_groups)
     {
         if (*address_len_ptr > 148) {
             // Maximum length of address registrations
             continue;
         }
-        if (addr_ipv6_multicast_scope(entry->group) < IPV6_SCOPE_REALM_LOCAL) {
-            /* Skip Link Local multicast address */
+
+        if (!memcmp((entry->group), ADDR_MULTICAST_SOLICITED, 13)) {
+            /* Skip solicited node multicast address */
             continue;
         }
-
         if (addr_ipv6_equal(entry->group, thread_realm_local_mcast_addr)) {
             /* Skip well-known realm-local all Thread nodes multicast address */
             continue;
         }
+        if (addr_ipv6_equal(entry->group, thread_ll_unicast_prefix_based_mcast_addr)) {
+            /* Skip well-known link-local all Thread nodes multicast address */
+            continue;
+        }
         if (addr_ipv6_equal(entry->group, ADDR_ALL_MPL_FORWARDERS)) {
             /* Skip All MPL Forwarders address */
             continue;
@@ -2058,7 +2067,7 @@ void thread_mcast_group_change(struct protocol_interface_info_entry *interface,
 
     if (thread_bootstrap_should_register_address(interface)) {
         /* Trigger Child Update Request only if MTD child's multicast address change */
-        if (addr_ipv6_multicast_scope(group->group) > IPV6_SCOPE_LINK_LOCAL) {
+        if (addr_ipv6_multicast_scope(group->group) >= IPV6_SCOPE_LINK_LOCAL) {
             interface->thread_info->childUpdateReqTimer = 1;
         }
     } else {

source/6LoWPAN/Thread/thread_router_bootstrap.c

@@ -1415,8 +1415,8 @@ static void thread_address_registration_tlv_parse(uint8_t *ptr, uint16_t data_le
             tr_debug("Register %s", trace_ipv6(ptr));
 
             if (addr_is_ipv6_multicast(ptr)) {
-                // Register multicast address (higher scope than link-local)
-                if (addr_ipv6_multicast_scope(ptr) > IPV6_SCOPE_LINK_LOCAL) {
+                // Register multicast address (link-local & higher)
+                if (addr_ipv6_multicast_scope(ptr) >= IPV6_SCOPE_LINK_LOCAL) {
                     addr_add_group(cur, ptr);
                     if (thread_child_mcast_entry_get(cur, ptr, mac64)) {
                         tr_debug("Added sleepy multicast registration entry.");