contiki/core/net/rpl/rpl.c
George Oikonomou 68f59113d6 Fix a route lifetime bug
There is a bug in the current route purge routine which would
result in a route's lifetime getting decremented more than once
during the same pass. This commit fixes it

The bug is documented here:
http://thread.gmane.org/gmane.os.contiki.devel/16209
2012-12-20 00:17:33 +00:00

265 lines
7.8 KiB
C

/**
* \addtogroup uip6
* @{
*/
/*
* Copyright (c) 2009, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*/
/**
* \file
* ContikiRPL, an implementation of RPL: IPv6 Routing Protocol
* for Low-Power and Lossy Networks (IETF RFC 6550)
*
* \author Joakim Eriksson <joakime@sics.se>, Nicolas Tsiftes <nvt@sics.se>
*/
#include "net/uip.h"
#include "net/tcpip.h"
#include "net/uip-ds6.h"
#include "net/rpl/rpl-private.h"
#include "net/neighbor-info.h"
#define DEBUG DEBUG_NONE
#include "net/uip-debug.h"
#include <limits.h>
#include <string.h>
#if RPL_CONF_STATS
rpl_stats_t rpl_stats;
#endif
/*---------------------------------------------------------------------------*/
void
rpl_purge_routes(void)
{
uip_ds6_route_t *r;
/* First pass, decrement lifetime */
r = uip_ds6_route_list_head();
while(r != NULL) {
if(r->state.lifetime >= 1) {
/*
* If a route is at lifetime == 1, set it to 0, scheduling it for
* immediate removal below. This achieves the same as the original code,
* which would delete lifetime <= 1
*/
r->state.lifetime--;
}
r = list_item_next(r);
}
/* Second pass, remove dead routes */
r = uip_ds6_route_list_head();
while(r != NULL) {
if(r->state.lifetime < 1) {
/* Routes with lifetime == 1 have only just been decremented from 2 to 1,
* thus we want to keep them. Hence < and not <= */
uip_ds6_route_rm(r);
r = uip_ds6_route_list_head();
} else {
r = list_item_next(r);
}
}
}
/*---------------------------------------------------------------------------*/
void
rpl_remove_routes(rpl_dag_t *dag)
{
uip_ds6_route_t *r;
r = uip_ds6_route_list_head();
while(r != NULL) {
if(r->state.dag == dag) {
uip_ds6_route_rm(r);
r = uip_ds6_route_list_head();
} else {
r = list_item_next(r);
}
}
}
/*---------------------------------------------------------------------------*/
void
rpl_remove_routes_by_nexthop(uip_ipaddr_t *nexthop, rpl_dag_t *dag)
{
uip_ds6_route_t *r;
r = uip_ds6_route_list_head();
while(r != NULL) {
if(uip_ipaddr_cmp(&r->nexthop, nexthop) &&
r->state.dag == dag) {
uip_ds6_route_rm(r);
r = uip_ds6_route_list_head();
} else {
r = list_item_next(r);
}
}
ANNOTATE("#L %u 0\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
#if 0
uip_ds6_route_t *locroute;
for(locroute = uip_ds6_routing_table;
locroute < uip_ds6_routing_table + UIP_DS6_ROUTE_NB;
locroute++) {
if(locroute->isused
&& uip_ipaddr_cmp(&locroute->nexthop, nexthop)
&& locroute->state.dag == dag) {
locroute->isused = 0;
}
}
ANNOTATE("#L %u 0\n",nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
#endif /* 0 */
}
/*---------------------------------------------------------------------------*/
uip_ds6_route_t *
rpl_add_route(rpl_dag_t *dag, uip_ipaddr_t *prefix, int prefix_len,
uip_ipaddr_t *next_hop)
{
uip_ds6_route_t *rep;
rep = uip_ds6_route_lookup(prefix);
if(rep == NULL) {
if((rep = uip_ds6_route_add(prefix, prefix_len, next_hop, 0)) == NULL) {
PRINTF("RPL: No space for more route entries\n");
return NULL;
}
} else {
PRINTF("RPL: Updated the next hop for prefix ");
PRINT6ADDR(prefix);
PRINTF(" to ");
PRINT6ADDR(next_hop);
PRINTF("\n");
uip_ipaddr_copy(&rep->nexthop, next_hop);
}
rep->state.dag = dag;
rep->state.lifetime = RPL_LIFETIME(dag->instance, dag->instance->default_lifetime);
rep->state.learned_from = RPL_ROUTE_FROM_INTERNAL;
PRINTF("RPL: Added a route to ");
PRINT6ADDR(prefix);
PRINTF("/%d via ", prefix_len);
PRINT6ADDR(next_hop);
PRINTF("\n");
return rep;
}
/*---------------------------------------------------------------------------*/
static void
rpl_link_neighbor_callback(const rimeaddr_t *addr, int known, int etx)
{
uip_ipaddr_t ipaddr;
rpl_parent_t *parent;
rpl_instance_t *instance;
rpl_instance_t *end;
uip_ip6addr(&ipaddr, 0xfe80, 0, 0, 0, 0, 0, 0, 0);
uip_ds6_set_addr_iid(&ipaddr, (uip_lladdr_t *)addr);
PRINTF("RPL: Neighbor ");
PRINT6ADDR(&ipaddr);
PRINTF(" is %sknown. ETX = %u\n", known ? "" : "no longer ", NEIGHBOR_INFO_FIX2ETX(etx));
for(instance = &instance_table[0], end = instance + RPL_MAX_INSTANCES; instance < end; ++instance) {
if(instance->used == 1 ) {
parent = rpl_find_parent_any_dag(instance, &ipaddr);
if(parent != NULL) {
/* Trigger DAG rank recalculation. */
parent->updated = 1;
parent->link_metric = etx;
if(instance->of->parent_state_callback != NULL) {
instance->of->parent_state_callback(parent, known, etx);
}
if(!known) {
PRINTF("RPL: Removing parent ");
PRINT6ADDR(&parent->addr);
PRINTF(" in instance %u because of bad connectivity (ETX %d)\n", instance->instance_id, etx);
parent->rank = INFINITE_RANK;
}
}
}
}
if(!known) {
PRINTF("RPL: Deleting routes installed by DAOs received from ");
PRINT6ADDR(&ipaddr);
PRINTF("\n");
uip_ds6_route_rm_by_nexthop(&ipaddr);
}
}
/*---------------------------------------------------------------------------*/
void
rpl_ipv6_neighbor_callback(uip_ds6_nbr_t *nbr)
{
rpl_parent_t *p;
rpl_instance_t *instance;
rpl_instance_t *end;
if(!nbr->isused) {
PRINTF("RPL: Removing neighbor ");
PRINT6ADDR(&nbr->ipaddr);
PRINTF("\n");
for(instance = &instance_table[0], end = instance + RPL_MAX_INSTANCES; instance < end; ++instance) {
if(instance->used == 1 ) {
p = rpl_find_parent_any_dag(instance, &nbr->ipaddr);
if(p != NULL) {
p->rank = INFINITE_RANK;
/* Trigger DAG rank recalculation. */
p->updated = 1;
}
}
}
}
}
/*---------------------------------------------------------------------------*/
void
rpl_init(void)
{
uip_ipaddr_t rplmaddr;
PRINTF("RPL started\n");
default_instance = NULL;
rpl_reset_periodic_timer();
neighbor_info_subscribe(rpl_link_neighbor_callback);
/* add rpl multicast address */
uip_create_linklocal_rplnodes_mcast(&rplmaddr);
uip_ds6_maddr_add(&rplmaddr);
#if RPL_CONF_STATS
memset(&rpl_stats, 0, sizeof(rpl_stats));
#endif
}
/*---------------------------------------------------------------------------*/