fixed clearing of state flag and avoid starting retransmission timer

core/net/ipv6/uip-ds6-route.h

@@ -106,6 +106,9 @@ void uip_ds6_notification_rm(struct uip_ds6_notification *n);
 #define RPL_ROUTE_SET_NOPATH_RECEIVED(route) do {                       \
     (route)->state.state_flags |= RPL_ROUTE_ENTRY_NOPATH_RECEIVED;      \
   } while(0)
+#define RPL_ROUTE_CLEAR_NOPATH_RECEIVED(route) do {                       \
+    (route)->state.state_flags &= ~RPL_ROUTE_ENTRY_NOPATH_RECEIVED;      \
+  } while(0)
 
 #define RPL_ROUTE_IS_DAO_PENDING(route)                                 \
   ((route->state.state_flags & RPL_ROUTE_ENTRY_DAO_PENDING) != 0)

core/net/ipv6/uip-nd6.c

@@ -201,6 +201,8 @@ ns_input(void)
 #endif /*UIP_CONF_IPV6_CHECKS */
         nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
         if(nbr == NULL) {
+          uip_lladdr_t lladdr_aligned;
+          extract_lladdr_aligned(&lladdr_aligned);
           uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
 			  0, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
         } else {
@@ -638,12 +640,11 @@ rs_input(void)
       } else {
         /* If LL address changed, set neighbor state to stale */
         if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
-            uip_ds6_nbr_get_ll(nbr), UIP_LLADDR_LEN) != 0) {
+                  uip_ds6_nbr_get_ll(nbr), UIP_LLADDR_LEN) != 0) {
           uip_ds6_nbr_t nbr_data = *nbr;
           uip_ds6_nbr_rm(nbr);
           nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
-          nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, 0, NBR_STALE,
+                                0, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
-                                NBR_TABLE_REASON_IPV6_ND, NULL);
           nbr->reachable = nbr_data.reachable;
           nbr->sendns = nbr_data.sendns;
           nbr->nscount = nbr_data.nscount;
@@ -872,8 +873,8 @@ ra_input(void)
       if(nbr == NULL) {
         uip_lladdr_t lladdr_aligned;
         extract_lladdr_aligned(&lladdr_aligned);
-        nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned, 1,
+        nbr = uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr_aligned,
-                              NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
+                              1, NBR_STALE, NBR_TABLE_REASON_IPV6_ND, NULL);
       } else {
         uip_lladdr_t *lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
         if(nbr->state == NBR_INCOMPLETE) {

core/net/rpl/rpl-icmp6.c

@@ -53,6 +53,7 @@
 #include "net/rpl/rpl-private.h"
 #include "net/packetbuf.h"
 #include "net/ipv6/multicast/uip-mcast6.h"
+#include "random.h"
 
 #include <limits.h>
 #include <string.h>
@@ -811,11 +812,12 @@ dao_input(void)
         uip_icmp6_send(rpl_get_parent_ipaddr(dag->preferred_parent),
                        ICMP6_RPL, RPL_CODE_DAO, buffer_length);
       }
-      if(flags & RPL_DAO_K_FLAG) {
+    } 
-        /* indicate that we accepted the no-path DAO */
+    /* independent if we remove or not - ACK the request */
-        dao_ack_output(instance, &dao_sender_addr, sequence,
+    if(flags & RPL_DAO_K_FLAG) {
-               RPL_DAO_ACK_UNCONDITIONAL_ACCEPT);
+      /* indicate that we accepted the no-path DAO */
-      }
+      dao_ack_output(instance, &dao_sender_addr, sequence,
+                     RPL_DAO_ACK_UNCONDITIONAL_ACCEPT);
     }
     goto discard;
   }
@@ -851,8 +853,9 @@ dao_input(void)
     goto discard;
   }
 
-  /* State is all zeroes, set lifetime but no need for other initialization. */
+  /* set lifetime and clear NOPATH bit */
   rep->state.lifetime = RPL_LIFETIME(instance, lifetime);
+  RPL_ROUTE_CLEAR_NOPATH_RECEIVED(rep);
 
 #if RPL_CONF_MULTICAST
 fwd_dao:
@@ -978,15 +981,13 @@ dao_output(rpl_parent_t *parent, uint8_t lifetime)
 
   /* Sending a DAO with own prefix as target */
   dao_output_target(parent, &prefix, lifetime);
-  /* keep track of my own sending of DAO for handling ack and loss of ack */
-  instance->my_dao_seqno = dao_sequence;
-
 #if RPL_WITH_DAO_ACK
-  instance->my_dao_transmissions = 1;
+  /* keep track of my own sending of DAO for handling ack and loss of ack */
-  ctimer_set(&instance->dao_retransmit_timer, RPL_DAO_RETRANSMISSION_TIMEOUT,
+  if(lifetime != RPL_ZERO_LIFETIME) {
-	     handle_dao_retransmission, parent);
+    instance->my_dao_seqno = dao_sequence;
-  if(lifetime == RPL_ZERO_LIFETIME) {
+    instance->my_dao_transmissions = 1;
-    rpl_set_downward_link(0);
+    ctimer_set(&instance->dao_retransmit_timer, RPL_DAO_RETRANSMISSION_TIMEOUT,
+	       handle_dao_retransmission, parent);
   }
 #else
   /* We know that we have tried to register so now we are assuming

core/net/rpl/rpl.c

@@ -238,6 +238,8 @@ rpl_add_route(rpl_dag_t *dag, uip_ipaddr_t *prefix, int prefix_len,
 
   rep->state.dag = dag;
   rep->state.lifetime = RPL_LIFETIME(dag->instance, dag->instance->default_lifetime);
+  /* always clear state flags for the no-path received when adding/refreshing */
+  RPL_ROUTE_CLEAR_NOPATH_RECEIVED(rep);
 
   PRINTF("RPL: Added a route to ");
   PRINT6ADDR(prefix);