nes-proj/os/net/routing/rpl-lite/rpl-dag.c
2018-04-13 18:07:39 +02:00

746 lines
25 KiB
C

/*
* Copyright (c) 2010, 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.
*
*/
/**
* \addtogroup rpl-lite
* @{
*
* \file
* Logic for Directed Acyclic Graphs in RPL.
*
* \author Joakim Eriksson <joakime@sics.se>, Nicolas Tsiftes <nvt@sics.se>,
* Simon Duquennoy <simon.duquennoy@inria.fr>
* Contributors: George Oikonomou <oikonomou@users.sourceforge.net> (multicast)
*/
#include "net/routing/rpl-lite/rpl.h"
#include "net/ipv6/uip-sr.h"
#include "net/nbr-table.h"
#include "net/link-stats.h"
/* Log configuration */
#include "sys/log.h"
#define LOG_MODULE "RPL"
#define LOG_LEVEL LOG_LEVEL_RPL
/*---------------------------------------------------------------------------*/
extern rpl_of_t rpl_of0, rpl_mrhof;
static rpl_of_t * const objective_functions[] = RPL_SUPPORTED_OFS;
static int init_dag_from_dio(rpl_dio_t *dio);
/*---------------------------------------------------------------------------*/
/* Allocate instance table. */
rpl_instance_t curr_instance;
/*---------------------------------------------------------------------------*/
const char *
rpl_dag_state_to_str(enum rpl_dag_state state)
{
switch(state) {
case DAG_INITIALIZED:
return "initialized";
case DAG_JOINED:
return "joined";
case DAG_REACHABLE:
return "reachable";
case DAG_POISONING:
return "poisoning";
default:
return "unknown";
}
}
/*---------------------------------------------------------------------------*/
int
rpl_dag_get_root_ipaddr(uip_ipaddr_t *ipaddr)
{
if(curr_instance.used && ipaddr != NULL) {
uip_ipaddr_copy(ipaddr, &curr_instance.dag.dag_id);
return 1;
}
return 0;
}
/*---------------------------------------------------------------------------*/
void
rpl_dag_leave(void)
{
LOG_INFO("leaving DAG ");
LOG_INFO_6ADDR(&curr_instance.dag.dag_id);
LOG_INFO_(", instance %u\n", curr_instance.instance_id);
/* Issue a no-path DAO */
if(!rpl_dag_root_is_root()) {
RPL_LOLLIPOP_INCREMENT(curr_instance.dag.dao_curr_seqno);
rpl_icmp6_dao_output(0);
}
/* Forget past link statistics */
link_stats_reset();
/* Remove all neighbors and lnks */
rpl_neighbor_remove_all();
uip_sr_free_all();
/* Stop all timers */
rpl_timers_stop_dag_timers();
/* Remove autoconfigured address */
if((curr_instance.dag.prefix_info.flags & UIP_ND6_RA_FLAG_AUTONOMOUS)) {
rpl_reset_prefix(&curr_instance.dag.prefix_info);
}
/* Mark instance as unused */
curr_instance.used = 0;
}
/*---------------------------------------------------------------------------*/
void
rpl_dag_poison_and_leave(void)
{
curr_instance.dag.state = DAG_POISONING;
rpl_timers_schedule_state_update();
}
/*---------------------------------------------------------------------------*/
void
rpl_dag_periodic(unsigned seconds)
{
if(curr_instance.used) {
if(curr_instance.dag.lifetime != RPL_LIFETIME(RPL_INFINITE_LIFETIME)) {
curr_instance.dag.lifetime =
curr_instance.dag.lifetime > seconds ? curr_instance.dag.lifetime - seconds : 0;
if(curr_instance.dag.lifetime == 0) {
LOG_WARN("DAG expired, poison and leave\n");
curr_instance.dag.state = DAG_POISONING;
rpl_timers_schedule_state_update();
} else if(curr_instance.dag.lifetime < 300 && curr_instance.dag.preferred_parent != NULL) {
/* Five minutes before expiring, start sending unicast DIS to get an update */
LOG_WARN("DAG expiring in %u seconds, send DIS to preferred parent\n", (unsigned)curr_instance.dag.lifetime);
rpl_icmp6_dis_output(rpl_neighbor_get_ipaddr(curr_instance.dag.preferred_parent));
}
}
}
}
/*---------------------------------------------------------------------------*/
int
rpl_is_addr_in_our_dag(const uip_ipaddr_t *addr)
{
return curr_instance.used
&& uip_ipaddr_prefixcmp(&curr_instance.dag.dag_id, addr, curr_instance.dag.prefix_info.length);
}
/*---------------------------------------------------------------------------*/
rpl_instance_t *
rpl_get_default_instance(void)
{
return curr_instance.used ? &curr_instance : NULL;
}
/*---------------------------------------------------------------------------*/
rpl_dag_t *
rpl_get_any_dag(void)
{
return curr_instance.used ? &curr_instance.dag : NULL;
}
/*---------------------------------------------------------------------------*/
static rpl_of_t *
find_objective_function(rpl_ocp_t ocp)
{
unsigned int i;
for(i = 0; i < sizeof(objective_functions) / sizeof(objective_functions[0]); i++) {
if(objective_functions[i]->ocp == ocp) {
return objective_functions[i];
}
}
return NULL;
}
/*---------------------------------------------------------------------------*/
void
rpl_refresh_routes(const char *str)
{
if(rpl_dag_root_is_root()) {
/* Increment DTSN */
RPL_LOLLIPOP_INCREMENT(curr_instance.dtsn_out);
LOG_WARN("incremented DTSN (%s), current %u\n",
str, curr_instance.dtsn_out);
if(LOG_INFO_ENABLED) {
rpl_neighbor_print_list("Refresh routes (before)");
}
}
}
/*---------------------------------------------------------------------------*/
void
rpl_global_repair(const char *str)
{
if(rpl_dag_root_is_root()) {
RPL_LOLLIPOP_INCREMENT(curr_instance.dag.version); /* New DAG version */
curr_instance.dtsn_out = RPL_LOLLIPOP_INIT; /* Re-initialize DTSN */
LOG_WARN("initiating global repair (%s), version %u, rank %u\n",
str, curr_instance.dag.version, curr_instance.dag.rank);
if(LOG_INFO_ENABLED) {
rpl_neighbor_print_list("Global repair (before)");
}
/* Now do a local repair to disseminate the new version */
rpl_local_repair("Global repair");
}
}
/*---------------------------------------------------------------------------*/
static void
global_repair_non_root(rpl_dio_t *dio)
{
if(!rpl_dag_root_is_root()) {
LOG_WARN("participating in global repair, version %u, rank %u\n",
dio->version, curr_instance.dag.rank);
if(LOG_INFO_ENABLED) {
rpl_neighbor_print_list("Global repair (before)");
}
/* Re-initialize configuration from DIO */
rpl_timers_stop_dag_timers();
init_dag_from_dio(dio);
rpl_local_repair("Global repair");
}
}
/*---------------------------------------------------------------------------*/
void
rpl_local_repair(const char *str)
{
if(curr_instance.used) { /* Check needed because this is a public function */
LOG_WARN("local repair (%s)\n", str);
if(!rpl_dag_root_is_root()) {
curr_instance.dag.state = DAG_INITIALIZED; /* Reset DAG state */
}
curr_instance.of->reset(); /* Reset OF */
rpl_neighbor_remove_all(); /* Remove all neighbors */
rpl_timers_dio_reset("Local repair"); /* Reset Trickle timer */
rpl_timers_schedule_state_update();
}
}
/*---------------------------------------------------------------------------*/
int
rpl_dag_ready_to_advertise(void)
{
if(curr_instance.mop == RPL_MOP_NO_DOWNWARD_ROUTES) {
return curr_instance.used && curr_instance.dag.state >= DAG_INITIALIZED;
} else {
return curr_instance.used && curr_instance.dag.state >= DAG_REACHABLE;
}
}
/*---------------------------------------------------------------------------*/
/* Updates rank and parent */
void
rpl_dag_update_state(void)
{
rpl_rank_t old_rank;
if(!curr_instance.used) {
return;
}
old_rank = curr_instance.dag.rank;
/* Any scheduled state update is no longer needed */
rpl_timers_unschedule_state_update();
if(curr_instance.dag.state == DAG_POISONING) {
rpl_neighbor_set_preferred_parent(NULL);
curr_instance.dag.rank = RPL_INFINITE_RANK;
if(old_rank != RPL_INFINITE_RANK) {
/* Advertise that we are leaving, and leave after a delay */
LOG_WARN("poisoning and leaving after a delay\n");
rpl_timers_dio_reset("Poison routes");
rpl_timers_schedule_leaving();
}
} else if(!rpl_dag_root_is_root()) {
rpl_nbr_t *old_parent = curr_instance.dag.preferred_parent;
rpl_nbr_t *nbr;
/* Select and set preferred parent */
rpl_neighbor_set_preferred_parent(rpl_neighbor_select_best());
/* Update rank */
curr_instance.dag.rank = rpl_neighbor_rank_via_nbr(curr_instance.dag.preferred_parent);
/* Update better_parent_since flag for each neighbor */
nbr = nbr_table_head(rpl_neighbors);
while(nbr != NULL) {
if(rpl_neighbor_rank_via_nbr(nbr) < curr_instance.dag.rank) {
/* This neighbor would be a better parent than our current.
Set 'better_parent_since' if not already set. */
if(nbr->better_parent_since == 0) {
nbr->better_parent_since = clock_time(); /* Initialize */
}
} else {
nbr->better_parent_since = 0; /* Not a better parent */
}
nbr = nbr_table_next(rpl_neighbors, nbr);
}
if(old_parent == NULL || curr_instance.dag.rank < curr_instance.dag.lowest_rank) {
/* This is a slight departure from RFC6550: if we had no preferred parent before,
* reset lowest_rank. This helps recovering from temporary bad link conditions. */
curr_instance.dag.lowest_rank = curr_instance.dag.rank;
}
/* Reset DIO timer in case of significant rank update */
if(curr_instance.dag.last_advertised_rank != RPL_INFINITE_RANK
&& curr_instance.dag.rank != RPL_INFINITE_RANK
&& ABS((int32_t)curr_instance.dag.rank - curr_instance.dag.last_advertised_rank) > RPL_SIGNIFICANT_CHANGE_THRESHOLD) {
LOG_WARN("significant rank update %u->%u\n",
curr_instance.dag.last_advertised_rank, curr_instance.dag.rank);
/* Update already here to avoid multiple resets in a row */
curr_instance.dag.last_advertised_rank = curr_instance.dag.rank;
rpl_timers_dio_reset("Significant rank update");
}
/* Parent switch */
if(curr_instance.dag.preferred_parent != old_parent) {
/* We just got a parent (was NULL), reset trickle timer to advertise this */
if(old_parent == NULL) {
curr_instance.dag.state = DAG_JOINED;
rpl_timers_dio_reset("Got parent");
LOG_WARN("found parent: ");
LOG_WARN_6ADDR(rpl_neighbor_get_ipaddr(curr_instance.dag.preferred_parent));
LOG_WARN_(", staying in DAG\n");
rpl_timers_unschedule_leaving();
}
/* Schedule a DAO */
if(curr_instance.dag.preferred_parent != NULL) {
rpl_timers_schedule_dao();
} else {
/* We have no more parent, schedule DIS to get a chance to hear updated state */
curr_instance.dag.state = DAG_INITIALIZED;
LOG_WARN("no parent, scheduling periodic DIS, will leave if no parent is found\n");
rpl_timers_dio_reset("Poison routes");
rpl_timers_schedule_periodic_dis();
rpl_timers_schedule_leaving();
}
if(LOG_INFO_ENABLED) {
rpl_neighbor_print_list("Parent switch");
}
}
}
/* Finally, update metric container */
curr_instance.of->update_metric_container();
}
/*---------------------------------------------------------------------------*/
static rpl_nbr_t *
update_nbr_from_dio(uip_ipaddr_t *from, rpl_dio_t *dio)
{
rpl_nbr_t *nbr = NULL;
const uip_lladdr_t *lladdr;
nbr = rpl_neighbor_get_from_ipaddr(from);
/* Neighbor not in RPL neighbor table, add it */
if(nbr == NULL) {
/* Is the neighbor known by ds6? Drop this request if not.
* Typically, the neighbor is added upon receiving a DIO. */
lladdr = uip_ds6_nbr_lladdr_from_ipaddr(from);
if(lladdr == NULL) {
return NULL;
}
/* Add neighbor to RPL table */
nbr = nbr_table_add_lladdr(rpl_neighbors, (linkaddr_t *)lladdr,
NBR_TABLE_REASON_RPL_DIO, dio);
if(nbr == NULL) {
LOG_ERR("failed to add neighbor\n");
return NULL;
}
}
/* Update neighbor info from DIO */
nbr->rank = dio->rank;
nbr->dtsn = dio->dtsn;
#if RPL_WITH_MC
memcpy(&nbr->mc, &dio->mc, sizeof(nbr->mc));
#endif /* RPL_WITH_MC */
return nbr;
}
/*---------------------------------------------------------------------------*/
static void
process_dio_from_current_dag(uip_ipaddr_t *from, rpl_dio_t *dio)
{
rpl_nbr_t *nbr;
uint8_t last_dtsn;
/* Does the rank make sense at all? */
if(dio->rank < ROOT_RANK) {
return;
}
/* If the DIO sender is on an older version of the DAG, do not process it
* further. The sender will eventually hear the global repair and catch up. */
if(rpl_lollipop_greater_than(curr_instance.dag.version, dio->version)) {
if(dio->rank == ROOT_RANK) {
/* Before returning, if the DIO was from the root, an old DAG versions
* likely incidates a root reboot. Reset our DIO timer to make sure the
* root hears our version ASAP, and in turn triggers a global repair. */
rpl_timers_dio_reset("Heard old version from root");
}
return;
}
/* The DIO is valid, proceed further */
/* Update DIO counter for redundancy mngt */
if(dio->rank != RPL_INFINITE_RANK) {
curr_instance.dag.dio_counter++;
}
/* The DIO has a newer version: global repair.
* Must come first, as it might remove all neighbors, and we then need
* to re-add this source of the DIO to the neighbor table */
if(rpl_lollipop_greater_than(dio->version, curr_instance.dag.version)) {
if(curr_instance.dag.rank == ROOT_RANK) {
/* The root should not hear newer versions unless it just rebooted */
LOG_ERR("inconsistent DIO version (current: %u, received: %u), initiate global repair\n",
curr_instance.dag.version, dio->version);
/* Update version and trigger global repair */
curr_instance.dag.version = dio->version;
rpl_global_repair("Inconsistent DIO version");
} else {
LOG_WARN("new DIO version (current: %u, received: %u), apply global repair\n",
curr_instance.dag.version, dio->version);
global_repair_non_root(dio);
}
}
/* Update IPv6 neighbor cache */
if(!rpl_icmp6_update_nbr_table(from, NBR_TABLE_REASON_RPL_DIO, dio)) {
LOG_ERR("IPv6 cache full, dropping DIO\n");
return;
}
/* Add neighbor to RPL neighbor table */
nbr = rpl_neighbor_get_from_ipaddr(from);
last_dtsn = nbr != NULL ? nbr->dtsn : RPL_LOLLIPOP_INIT;
if(!update_nbr_from_dio(from, dio)) {
LOG_ERR("neighbor table full, dropping DIO\n");
return;
}
/* Init lifetime if not set yet. Refresh it at every DIO from preferred parent. */
if(curr_instance.dag.lifetime == 0 ||
(nbr != NULL && nbr == curr_instance.dag.preferred_parent)) {
LOG_INFO("refreshing lifetime\n");
curr_instance.dag.lifetime = RPL_LIFETIME(RPL_DAG_LIFETIME);
}
/* If the source is our preferred parent and it increased DTSN, we increment
* our DTSN in turn and schedule a DAO (see RFC6550 section 9.6.) */
if(curr_instance.mop != RPL_MOP_NO_DOWNWARD_ROUTES) {
if(nbr != NULL && nbr == curr_instance.dag.preferred_parent && rpl_lollipop_greater_than(dio->dtsn, last_dtsn)) {
RPL_LOLLIPOP_INCREMENT(curr_instance.dtsn_out);
LOG_WARN("DTSN increment %u->%u, schedule new DAO with DTSN %u\n",
last_dtsn, dio->dtsn, curr_instance.dtsn_out);
rpl_timers_schedule_dao();
}
}
}
/*---------------------------------------------------------------------------*/
static int
init_dag(uint8_t instance_id, uip_ipaddr_t *dag_id, rpl_ocp_t ocp,
uip_ipaddr_t *prefix, unsigned prefix_len, uint8_t prefix_flags)
{
rpl_of_t *of;
memset(&curr_instance, 0, sizeof(curr_instance));
/* OF */
of = find_objective_function(ocp);
if(of == NULL) {
LOG_ERR("ignoring DIO with an unsupported OF: %u\n", ocp);
return 0;
}
/* Prefix */
if(!rpl_set_prefix_from_addr(prefix, prefix_len, prefix_flags)) {
LOG_ERR("failed to set prefix\n");
return 0;
}
/* Instnace */
curr_instance.instance_id = instance_id;
curr_instance.of = of;
curr_instance.dtsn_out = RPL_LOLLIPOP_INIT;
curr_instance.used = 1;
/* DAG */
curr_instance.dag.rank = RPL_INFINITE_RANK;
curr_instance.dag.last_advertised_rank = RPL_INFINITE_RANK;
curr_instance.dag.lowest_rank = RPL_INFINITE_RANK;
curr_instance.dag.dao_last_seqno = RPL_LOLLIPOP_INIT;
curr_instance.dag.dao_last_acked_seqno = RPL_LOLLIPOP_INIT;
curr_instance.dag.dao_curr_seqno = RPL_LOLLIPOP_INIT;
memcpy(&curr_instance.dag.dag_id, dag_id, sizeof(curr_instance.dag.dag_id));
return 1;
}
/*---------------------------------------------------------------------------*/
static int
init_dag_from_dio(rpl_dio_t *dio)
{
if(!init_dag(dio->instance_id, &dio->dag_id, dio->ocp,
&dio->prefix_info.prefix, dio->prefix_info.length, dio->prefix_info.flags)) {
return 0;
}
/* Instnace */
curr_instance.mop = dio->mop;
curr_instance.mc.type = dio->mc.type;
curr_instance.mc.flags = dio->mc.flags;
curr_instance.mc.aggr = dio->mc.aggr;
curr_instance.mc.prec = dio->mc.prec;
curr_instance.max_rankinc = dio->dag_max_rankinc;
curr_instance.min_hoprankinc = dio->dag_min_hoprankinc;
curr_instance.dio_intdoubl = dio->dag_intdoubl;
curr_instance.dio_intmin = dio->dag_intmin;
curr_instance.dio_redundancy = dio->dag_redund;
curr_instance.default_lifetime = dio->default_lifetime;
curr_instance.lifetime_unit = dio->lifetime_unit;
/* DAG */
curr_instance.dag.state = DAG_INITIALIZED;
curr_instance.dag.preference = dio->preference;
curr_instance.dag.grounded = dio->grounded;
curr_instance.dag.version = dio->version;
curr_instance.dag.dio_intcurrent = dio->dag_intmin;
return 1;
}
/*---------------------------------------------------------------------------*/
static int
process_dio_init_dag(uip_ipaddr_t *from, rpl_dio_t *dio)
{
/* Check MOP */
if(dio->mop != RPL_MOP_NO_DOWNWARD_ROUTES && dio->mop != RPL_MOP_NON_STORING) {
LOG_WARN("ignoring DIO with an unsupported MOP: %d\n", dio->mop);
return 0;
}
/* Initialize instance and DAG data structures */
if(!init_dag_from_dio(dio)) {
LOG_WARN("failed to initialize DAG\n");
return 0;
}
/* Init OF and timers */
curr_instance.of->reset();
rpl_timers_dio_reset("Join");
#if RPL_WITH_PROBING
rpl_schedule_probing();
#endif /* RPL_WITH_PROBING */
/* Leave the network after RPL_DELAY_BEFORE_LEAVING in case we do not
find a parent */
LOG_INFO("initialized DAG with instance ID %u, DAG ID ",
curr_instance.instance_id);
LOG_INFO_6ADDR(&curr_instance.dag.dag_id);
LOG_INFO_(", prexix ");
LOG_INFO_6ADDR(&dio->prefix_info.prefix);
LOG_INFO_("/%u, rank %u\n", dio->prefix_info.length, curr_instance.dag.rank);
LOG_ANNOTATE("#A init=%u\n", curr_instance.dag.dag_id.u8[sizeof(curr_instance.dag.dag_id) - 1]);
LOG_WARN("just joined, no parent yet, setting timer for leaving\n");
rpl_timers_schedule_leaving();
return 1;
}
/*---------------------------------------------------------------------------*/
void
rpl_process_dio(uip_ipaddr_t *from, rpl_dio_t *dio)
{
if(!curr_instance.used && !rpl_dag_root_is_root()) {
/* Attempt to init our DAG from this DIO */
if(!process_dio_init_dag(from, dio)) {
LOG_WARN("failed to init DAG\n");
return;
}
}
if(curr_instance.used
&& curr_instance.instance_id == dio->instance_id
&& uip_ipaddr_cmp(&curr_instance.dag.dag_id, &dio->dag_id)) {
process_dio_from_current_dag(from, dio);
rpl_dag_update_state();
}
}
/*---------------------------------------------------------------------------*/
void
rpl_process_dis(uip_ipaddr_t *from, int is_multicast)
{
if(is_multicast) {
rpl_timers_dio_reset("Multicast DIS");
} else {
/* Add neighbor to cache and reply to the unicast DIS with a unicast DIO*/
if(rpl_icmp6_update_nbr_table(from, NBR_TABLE_REASON_RPL_DIS, NULL) != NULL) {
LOG_INFO("unicast DIS, reply to sender\n");
rpl_icmp6_dio_output(from);
}
}
}
/*---------------------------------------------------------------------------*/
void
rpl_process_dao(uip_ipaddr_t *from, rpl_dao_t *dao)
{
if(dao->lifetime == 0) {
uip_sr_expire_parent(NULL, from, &dao->parent_addr);
} else {
if(!uip_sr_update_node(NULL, from, &dao->parent_addr, RPL_LIFETIME(dao->lifetime))) {
LOG_ERR("failed to add link on incoming DAO\n");
return;
}
}
#if RPL_WITH_DAO_ACK
if(dao->flags & RPL_DAO_K_FLAG) {
rpl_timers_schedule_dao_ack(from, dao->sequence);
}
#endif /* RPL_WITH_DAO_ACK */
}
/*---------------------------------------------------------------------------*/
#if RPL_WITH_DAO_ACK
void
rpl_process_dao_ack(uint8_t sequence, uint8_t status)
{
/* Update dao_last_acked_seqno */
if(rpl_lollipop_greater_than(sequence, curr_instance.dag.dao_last_acked_seqno)) {
curr_instance.dag.dao_last_acked_seqno = sequence;
}
/* Is this an ACK for our last DAO? */
if(sequence == curr_instance.dag.dao_last_seqno) {
int status_ok = status < RPL_DAO_ACK_UNABLE_TO_ACCEPT;
if(curr_instance.dag.state == DAG_JOINED && status_ok) {
curr_instance.dag.state = DAG_REACHABLE;
rpl_timers_dio_reset("Reachable");
}
if(!status_ok) {
/* We got a NACK, start poisoning and leave */
LOG_WARN("DAO-NACK received with seqno %u, status %u, poison and leave\n",
sequence, status);
curr_instance.dag.state = DAG_POISONING;
}
}
}
#endif /* RPL_WITH_DAO_ACK */
/*---------------------------------------------------------------------------*/
int
rpl_process_hbh(rpl_nbr_t *sender, uint16_t sender_rank, int loop_detected, int rank_error_signaled)
{
int drop = 0;
if(loop_detected) {
if(rank_error_signaled) {
#if RPL_LOOP_ERROR_DROP
/* Drop packet and reset trickle timer, as per RFC6550 - 11.2.2.2 */
rpl_timers_dio_reset("HBH error");
LOG_WARN("rank error and loop detected, dropping\n");
drop = 1;
#endif /* RPL_LOOP_ERROR_DROP */
}
/* Attempt to repair the loop by sending a unicast DIO back to the sender
* so that it gets a fresh update of our rank. */
rpl_timers_schedule_unicast_dio(sender);
}
if(rank_error_signaled) {
/* A rank error was signalled, attempt to repair it by updating
* the sender's rank from ext header */
if(sender != NULL) {
sender->rank = sender_rank;
/* Select DAG and preferred parent. In case of a parent switch,
the new parent will be used to forward the current packet. */
rpl_dag_update_state();
}
}
return !drop;
}
/*---------------------------------------------------------------------------*/
void
rpl_dag_init_root(uint8_t instance_id, uip_ipaddr_t *dag_id,
uip_ipaddr_t *prefix, unsigned prefix_len, uint8_t prefix_flags)
{
uint8_t version = RPL_LOLLIPOP_INIT;
/* If we're in an instance, first leave it */
if(curr_instance.used) {
/* We were already root. Increment version */
if(uip_ipaddr_cmp(&curr_instance.dag.dag_id, dag_id)) {
version = curr_instance.dag.version;
RPL_LOLLIPOP_INCREMENT(version);
}
rpl_dag_leave();
}
/* Init DAG and instance */
init_dag(instance_id, dag_id, RPL_OF_OCP, prefix, prefix_len, prefix_flags);
/* Instance */
curr_instance.mop = RPL_MOP_DEFAULT;
curr_instance.max_rankinc = RPL_MAX_RANKINC;
curr_instance.min_hoprankinc = RPL_MIN_HOPRANKINC;
curr_instance.dio_intdoubl = RPL_DIO_INTERVAL_DOUBLINGS;
curr_instance.dio_intmin = RPL_DIO_INTERVAL_MIN;
curr_instance.dio_redundancy = RPL_DIO_REDUNDANCY;
curr_instance.default_lifetime = RPL_DEFAULT_LIFETIME;
curr_instance.lifetime_unit = RPL_DEFAULT_LIFETIME_UNIT;
/* DAG */
curr_instance.dag.preference = RPL_PREFERENCE;
curr_instance.dag.grounded = RPL_GROUNDED;
curr_instance.dag.version = version;
curr_instance.dag.rank = ROOT_RANK;
curr_instance.dag.lifetime = RPL_LIFETIME(RPL_INFINITE_LIFETIME);
curr_instance.dag.dio_intcurrent = RPL_DIO_INTERVAL_MIN;
curr_instance.dag.state = DAG_REACHABLE;
rpl_timers_dio_reset("Init root");
LOG_INFO("created DAG with instance ID %u, DAG ID ",
curr_instance.instance_id);
LOG_INFO_6ADDR(&curr_instance.dag.dag_id);
LOG_INFO_(", rank %u\n", curr_instance.dag.rank);
LOG_ANNOTATE("#A root=%u\n", curr_instance.dag.dag_id.u8[sizeof(curr_instance.dag.dag_id) - 1]);
}
/*---------------------------------------------------------------------------*/
void
rpl_dag_init(void)
{
memset(&curr_instance, 0, sizeof(curr_instance));
}
/*---------------------------------------------------------------------------*/
/** @} */