Added storing of all MAC frame counters to NVM

PAE controller now stores all frame counters (for 4 keys) to NVM. Counters
are stored with GTKs so that frame counters can be accosicated with the
specific key.

Storing is triggered:
1) Keys are checked on 60 seconds interval. Storing to NVM is triggered
if keys (GTKs) are changed or frame counter storing is needed (defined by
hysteresis).
2) When new key is inserted (e.g. due to 4WH or GKH). There is 5 seconds
delay to give time for BR to insert several keys before NVM write is
triggered
3) When new send key index is taken into use. On most cases (1) or (2) should
be triggered before this check, in which case no NVM updates are needed on
this step
4) On ifdown

Reading is triggered:
1) On ifup

Added storing/reading MAC frame counters to MAC helper.

Re-wrote the key update code (ws_pae_controller_nw_key_check_and_insert) and
changed the checks to use actual GTKs instead of GTK hash.

Author: Mika Leppänen

source/6LoWPAN/MAC/mac_helper.c

@@ -834,20 +834,41 @@ int8_t mac_helper_link_frame_counter_read(int8_t interface_id, uint32_t *seq_ptr
 {
     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
 
+    if (!cur || !cur->mac_api || !seq_ptr) {
+        return -1;
+    }
+
+    return mac_helper_key_link_frame_counter_read(interface_id, seq_ptr, cur->mac_parameters->mac_default_key_attribute_id);
+}
+
+int8_t mac_helper_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr)
+{
+    protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
+
+    if (!cur || !cur->mac_api) {
+        return -1;
+    }
+
+    return mac_helper_key_link_frame_counter_set(interface_id, seq_ptr, cur->mac_parameters->mac_default_key_attribute_id);
+}
+
+int8_t mac_helper_key_link_frame_counter_read(int8_t interface_id, uint32_t *seq_ptr, uint8_t descriptor)
+{
+    protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
+
     if (!cur || !cur->mac_api || !seq_ptr) {
         return -1;
     }
     mlme_get_t get_req;
     get_req.attr = macFrameCounter;
-    get_req.attr_index = cur->mac_parameters->mac_default_key_attribute_id;
+    get_req.attr_index = descriptor;
     cur->mac_api->mlme_req(cur->mac_api, MLME_GET, &get_req);
     *seq_ptr = cur->mac_parameters->security_frame_counter;
 
     return 0;
 }
 
-
-int8_t mac_helper_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr)
+int8_t mac_helper_key_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr, uint8_t descriptor)
 {
     protocol_interface_info_entry_t *cur = protocol_stack_interface_info_get_by_id(interface_id);
 
@@ -856,7 +877,7 @@ int8_t mac_helper_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr)
     }
     mlme_set_t set_req;
     set_req.attr = macFrameCounter;
-    set_req.attr_index = cur->mac_parameters->mac_default_key_attribute_id;
+    set_req.attr_index = descriptor;
     set_req.value_pointer = &seq_ptr;
     set_req.value_size = 4;
     cur->mac_api->mlme_req(cur->mac_api, MLME_SET, &set_req);

source/6LoWPAN/MAC/mac_helper.h

@@ -115,6 +115,10 @@ int8_t mac_helper_link_frame_counter_read(int8_t interface_id, uint32_t *seq_ptr
 
 int8_t mac_helper_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr);
 
+int8_t mac_helper_key_link_frame_counter_read(int8_t interface_id, uint32_t *seq_ptr, uint8_t descriptor);
+
+int8_t mac_helper_key_link_frame_counter_set(int8_t interface_id, uint32_t seq_ptr, uint8_t descriptor);
+
 void mac_helper_devicetable_remove(struct mac_api_s *mac_api, uint8_t attribute_index, uint8_t *mac64);
 
 void mac_helper_device_description_write(struct protocol_interface_info_entry *cur, mlme_device_descriptor_t *device_desc, uint8_t *mac64, uint16_t mac16, uint32_t frame_counter, bool exempt);

source/6LoWPAN/ws/ws_bootstrap.c

@@ -90,8 +90,8 @@ static void ws_bootstrap_mac_security_enable(protocol_interface_info_entry_t *cu
 static void ws_bootstrap_nw_key_set(protocol_interface_info_entry_t *cur, uint8_t operation, uint8_t index, uint8_t *key);
 static void ws_bootstrap_nw_key_clear(protocol_interface_info_entry_t *cur, uint8_t slot);
 static void ws_bootstrap_nw_key_index_set(protocol_interface_info_entry_t *cur, uint8_t index);
-static void ws_bootstrap_nw_frame_counter_set(protocol_interface_info_entry_t *cur, uint32_t counter);
-static void ws_bootstrap_nw_frame_counter_read(protocol_interface_info_entry_t *cur, uint32_t *counter);
+static void ws_bootstrap_nw_frame_counter_set(protocol_interface_info_entry_t *cur, uint32_t counter, uint8_t slot);
+static void ws_bootstrap_nw_frame_counter_read(protocol_interface_info_entry_t *cur, uint32_t *counter, uint8_t slot);
 static void ws_bootstrap_authentication_completed(protocol_interface_info_entry_t *cur, auth_result_e result, uint8_t *target_eui_64);
 static void ws_bootstrap_pan_version_increment(protocol_interface_info_entry_t *cur);
 static ws_nud_table_entry_t *ws_nud_entry_discover(protocol_interface_info_entry_t *cur, void *neighbor);
@@ -2311,16 +2311,16 @@ static void ws_bootstrap_nw_key_index_set(protocol_interface_info_entry_t *cur,
     mac_helper_security_auto_request_key_index_set(cur, index, index + 1);
 }
 
-static void ws_bootstrap_nw_frame_counter_set(protocol_interface_info_entry_t *cur, uint32_t counter)
+static void ws_bootstrap_nw_frame_counter_set(protocol_interface_info_entry_t *cur, uint32_t counter, uint8_t slot)
 {
     // Set frame counter
-    mac_helper_link_frame_counter_set(cur->id, counter);
+    mac_helper_key_link_frame_counter_set(cur->id, counter, slot);
 }
 
-static void ws_bootstrap_nw_frame_counter_read(protocol_interface_info_entry_t *cur, uint32_t *counter)
+static void ws_bootstrap_nw_frame_counter_read(protocol_interface_info_entry_t *cur, uint32_t *counter, uint8_t slot)
 {
     // Read frame counter
-    mac_helper_link_frame_counter_read(cur->id, counter);
+    mac_helper_key_link_frame_counter_read(cur->id, counter, slot);
 }
 
 static void ws_bootstrap_authentication_completed(protocol_interface_info_entry_t *cur, auth_result_e result, uint8_t *target_eui_64)

source/6LoWPAN/ws/ws_config.h

@@ -135,6 +135,7 @@ extern uint8_t DEVICE_MIN_SENS;
  * MAC frame counter NVM storing configuration
  */
 #define FRAME_COUNTER_STORE_INTERVAL     60   // Time interval (on seconds) between frame counter store operations
+#define FRAME_COUNTER_STORE_TRIGGER      5    // Delay (on seconds) before storing, when storing of frame counters is triggered
 #define FRAME_COUNTER_INCREMENT          1000 // How much frame counter is incremented on start up
 #define FRAME_COUNTER_STORE_THRESHOLD    800  // How much frame counter must increment before it is stored