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pigweed / third_party / github / zephyrproject-rtos / zephyr / d211a52fc0f942ec8cac5ecff37bd549fbe13904 / . / subsys / net / ip / rpl.c
blob: a2a7ffdd067ddbc7a6c97fce08eb493d874b681c [file] [log] [blame]
/** @file
* @brief RPL (Ripple, RFC 6550) handling.
*
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* 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.
*/
#if defined(CONFIG_NET_DEBUG_RPL)
#define SYS_LOG_DOMAIN "net/rpl"
#define NET_DEBUG 1
#endif
#include <kernel.h>
#include <limits.h>
#include <stdint.h>
#include <net/nbuf.h>
#include <net/net_core.h>
#include <net/net_stats.h>
#include "net_private.h"
#include "ipv6.h"
#include "icmpv6.h"
#include "nbr.h"
#include "route.h"
#include "rpl.h"
#define NET_RPL_DIO_GROUNDED 0x80
#define NET_RPL_DIO_MOP_SHIFT 3
#define NET_RPL_DIO_MOP_MASK 0x38
#define NET_RPL_DIO_PREFERENCE_MASK 0x07
/* RPL IPv6 extension header option. */
#define NET_RPL_HDR_OPT_LEN 4
#define NET_RPL_HOP_BY_HOP_LEN (NET_RPL_HDR_OPT_LEN + 2 + 2)
#define NET_RPL_HDR_OPT_DOWN 0x80
#define NET_RPL_HDR_OPT_DOWN_SHIFT 7
#define NET_RPL_HDR_OPT_RANK_ERR 0x40
#define NET_RPL_HDR_OPT_RANK_ERR_SHIFT 6
#define NET_RPL_HDR_OPT_FWD_ERR 0x20
#define NET_RPL_HDR_OPT_FWD_ERR_SHIFT 5
/* Hop By Hop extension headers option type */
#define NET_RPL_EXT_HDR_OPT_RPL 0x63
/* Special value indicating immediate removal. */
#define NET_RPL_ZERO_LIFETIME 0
/* Expire DAOs from neighbors that do not respond in this time. (seconds) */
#define NET_RPL_DAO_EXPIRATION_TIMEOUT 60
#if defined(CONFIG_NET_RPL_MOP3)
#define NET_RPL_MOP_DEFAULT NET_RPL_MOP_STORING_MULTICAST
#else
#define NET_RPL_MOP_DEFAULT NET_RPL_MOP_STORING_NO_MULTICAST
#endif
#if defined(CONFIG_NET_RPL_MOP3)
#define NET_RPL_MULTICAST 1
#else
#define NET_RPL_MULTICAST 0
#endif
#if defined(CONFIG_NET_RPL_GROUNDED)
#define NET_RPL_GROUNDED true
#else
#define NET_RPL_GROUNDED false
#endif
#define NET_RPL_PARENT_FLAG_UPDATED 0x1
#define NET_RPL_PARENT_FLAG_LINK_METRIC_VALID 0x2
static struct net_rpl_instance rpl_instances[CONFIG_NET_RPL_MAX_INSTANCES];
static struct net_rpl_instance *rpl_default_instance;
static enum net_rpl_mode rpl_mode = NET_RPL_MODE_MESH;
static net_rpl_join_callback_t rpl_join_callback;
static uint8_t rpl_dao_sequence;
#if defined(CONFIG_NET_RPL_DIS_SEND)
/* DODAG Information Solicitation timer. */
struct k_delayed_work dis_timer;
#define NET_RPL_DIS_START_DELAY 5 /* in seconds */
#endif
/* This is set to true if we are able and ready to send any DIOs */
static bool rpl_dio_send_ok;
static int dao_send(struct net_rpl_parent *parent, uint8_t lifetime,
struct net_if *iface);
static void dao_send_timer(struct k_work *work);
static void set_dao_lifetime_timer(struct net_rpl_instance *instance);
static struct net_rpl_parent *find_parent(struct net_if *iface,
struct net_rpl_dag *dag,
struct in6_addr *addr);
static void remove_parents(struct net_if *iface,
struct net_rpl_dag *dag,
uint16_t minimum_rank);
static void net_rpl_schedule_dao_now(struct net_rpl_instance *instance);
void net_rpl_set_join_callback(net_rpl_join_callback_t cb)
{
rpl_join_callback = cb;
}
enum net_rpl_mode net_rpl_get_mode(void)
{
return rpl_mode;
}
static inline void net_rpl_cancel_dao(struct net_rpl_instance *instance)
{
k_delayed_work_cancel(&instance->dao_timer);
}
void net_rpl_set_mode(enum net_rpl_mode new_mode)
{
NET_ASSERT_INFO(new_mode >= NET_RPL_MODE_MESH &&
new_mode <= NET_RPL_MODE_LEAF,
"Invalid RPL mode %d", new_mode);
rpl_mode = new_mode;
/* We need to do different things depending on what mode we are
* switching to.
*/
if (rpl_mode == NET_RPL_MODE_MESH) {
/* If we switch to mesh mode, we should send out a DAO message
* to inform our parent that we now are reachable. Before we do
* this, we must set the mode variable, since DAOs will not be
* sent if we are in feather mode.
*/
NET_DBG("Switching to mesh mode");
if (rpl_default_instance) {
net_rpl_schedule_dao_now(rpl_default_instance);
}
} else if (rpl_mode == NET_RPL_MODE_FEATHER) {
NET_DBG("Switching to feather mode");
if (rpl_default_instance) {
net_rpl_cancel_dao(rpl_default_instance);
}
}
}
static inline uint32_t net_rpl_lifetime(struct net_rpl_instance *instance,
uint8_t lifetime)
{
return (uint32_t)instance->lifetime_unit * (uint32_t)lifetime;
}
static void net_rpl_neighbor_data_remove(struct net_nbr *nbr)
{
NET_DBG("Neighbor %p removed", nbr);
}
static void net_rpl_neighbor_table_clear(struct net_nbr_table *table)
{
NET_DBG("Neighbor table %p cleared", table);
}
NET_NBR_POOL_INIT(net_rpl_neighbor_pool, CONFIG_NET_IPV6_MAX_NEIGHBORS,
sizeof(struct net_rpl_parent),
net_rpl_neighbor_data_remove, 0);
NET_NBR_TABLE_INIT(NET_NBR_LOCAL, rpl_parents, net_rpl_neighbor_pool,
net_rpl_neighbor_table_clear);
#if NET_DEBUG
#define net_rpl_info(buf, req) \
do { \
char out[NET_IPV6_ADDR_LEN]; \
\
snprintf(out, sizeof(out), \
net_sprint_ipv6_addr(&NET_IPV6_BUF(buf)->dst)); \
NET_DBG("Received %s from %s to %s", req, \
net_sprint_ipv6_addr(&NET_IPV6_BUF(buf)->src), out); \
} while (0)
#define net_rpl_dao_info(buf, src, dst, prefix) \
do { \
char out[NET_IPV6_ADDR_LEN]; \
char prf[NET_IPV6_ADDR_LEN]; \
\
snprintf(out, sizeof(out), net_sprint_ipv6_addr(dst)); \
snprintf(prf, sizeof(prf), net_sprint_ipv6_addr(prefix)); \
NET_DBG("Send DAO with prefix %s from %s to %s", \
prf, net_sprint_ipv6_addr(src), out); \
} while (0)
#define net_rpl_dao_ack_info(buf, src, dst, id, seq) \
do { \
char out[NET_IPV6_ADDR_LEN]; \
\
snprintf(out, sizeof(out), net_sprint_ipv6_addr(dst)); \
NET_DBG("Send DAO-ACK (id %d, seq %d) from %s to %s", \
id, seq, net_sprint_ipv6_addr(src), out); \
} while (0)
#else /* NET_DEBUG */
#define net_rpl_info(...)
#define net_rpl_dao_info(...)
#define net_rpl_dao_ack_info(...)
#endif /* NET_DEBUG */
static void new_dio_interval(struct net_rpl_instance *instance);
static inline struct net_nbr *get_nbr(int idx)
{
return &net_rpl_neighbor_pool[idx].nbr;
}
static inline struct net_rpl_parent *nbr_data(struct net_nbr *nbr)
{
return (struct net_rpl_parent *)nbr->data;
}
struct net_nbr *net_rpl_get_nbr(struct net_rpl_parent *data)
{
int i;
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
if (nbr->data == (uint8_t *)data) {
return nbr;
}
}
return NULL;
}
static struct net_nbr *nbr_lookup(struct net_nbr_table *table,
struct net_if *iface,
struct in6_addr *addr)
{
int i;
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
if (nbr->ref && nbr->iface == iface &&
net_ipv6_addr_cmp(&nbr_data(nbr)->dag->dag_id, addr)) {
return nbr;
}
}
return NULL;
}
static inline void nbr_free(struct net_nbr *nbr)
{
NET_DBG("nbr %p", nbr);
net_nbr_unref(nbr);
}
static struct net_nbr *nbr_add(struct net_if *iface,
struct in6_addr *addr,
struct net_linkaddr *lladdr)
{
struct net_nbr *nbr = net_nbr_get(&net_rpl_parents.table);
int ret;
if (!nbr) {
return NULL;
}
ret = net_nbr_link(nbr, iface, lladdr);
if (ret) {
NET_DBG("nbr linking failure (%d)", ret);
nbr_free(nbr);
return NULL;
}
NET_DBG("[%d] nbr %p IPv6 %s ll %s",
nbr->idx, nbr, net_sprint_ipv6_addr(addr),
net_sprint_ll_addr(lladdr->addr, lladdr->len));
return nbr;
}
struct in6_addr *net_rpl_get_parent_addr(struct net_if *iface,
struct net_rpl_parent *parent)
{
struct net_nbr *nbr;
nbr = net_rpl_get_nbr(parent);
if (!nbr) {
NET_DBG("Parent %p unknown", parent);
return NULL;
}
return net_ipv6_nbr_lookup_by_index(iface, nbr->idx);
}
#if NET_DEBUG
static void net_rpl_print_neighbors(void)
{
if (rpl_default_instance && rpl_default_instance->current_dag) {
int curr_interval = rpl_default_instance->dio_interval_current;
int curr_rank = rpl_default_instance->current_dag->rank;
uint32_t now = k_uptime_get_32();
struct net_rpl_parent *parent;
int i;
NET_DBG("rank %u DIO interval %u", curr_rank,
curr_interval);
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *ipv6_nbr, *nbr = get_nbr(i);
struct in6_addr *parent_addr;
if (!nbr->ref) {
continue;
}
parent = nbr_data(nbr);
parent_addr =
net_rpl_get_parent_addr(net_if_get_default(),
parent);
ipv6_nbr = net_ipv6_nbr_lookup(net_if_get_default(),
parent_addr);
NET_DBG("[%d] nbr %s %5u %5u => %5u %c "
"(last tx %u min ago)",
nbr->idx,
net_sprint_ll_addr(
net_nbr_get_lladdr(nbr->idx)->addr,
net_nbr_get_lladdr(nbr->idx)->len),
parent->rank,
ipv6_nbr ?
net_ipv6_nbr_data(ipv6_nbr)->link_metric : 0,
net_rpl_of_calc_rank(parent, 0),
parent == rpl_default_instance->current_dag->
preferred_parent ? '*' : ' ',
(unsigned)((now - parent->last_tx_time) /
(60 * MSEC_PER_SEC)));
}
}
}
#else
#define net_rpl_print_neighbors(...)
#endif /* NET_DEBUG */
#if NET_DEBUG
#define net_route_info(str, route, addr, len, nexthop) \
do { \
char out[NET_IPV6_ADDR_LEN]; \
\
snprintf(out, sizeof(out), \
net_sprint_ipv6_addr(addr)); \
NET_DBG("%s route to %s via %s (iface %p)", str, out, \
net_sprint_ipv6_addr(nexthop), route->iface); \
} while (0)
#else
#define net_route_info(...)
#endif /* NET_DEBUG */
struct net_route_entry *net_rpl_add_route(struct net_rpl_dag *dag,
struct net_if *iface,
struct in6_addr *addr,
int prefix_len,
struct in6_addr *nexthop)
{
struct net_rpl_route_entry *extra;
struct net_route_entry *route;
struct net_nbr *nbr;
route = net_route_add(iface, addr, prefix_len, nexthop);
if (!route) {
return NULL;
}
nbr = net_route_get_nbr(route);
extra = net_nbr_extra_data(nbr);
extra->dag = dag;
extra->lifetime = net_rpl_lifetime(dag->instance,
dag->instance->default_lifetime);
extra->route_source = NET_RPL_ROUTE_INTERNAL;
net_route_info("Added", route, addr, prefix_len, nexthop);
return route;
}
static inline void setup_icmpv6_hdr(struct net_buf *buf, uint8_t type,
uint8_t code)
{
net_nbuf_append_u8(buf, type);
net_nbuf_append_u8(buf, code);
net_nbuf_append_be16(buf, 0); /* checksum */
}
int net_rpl_dio_send(struct net_if *iface,
struct net_rpl_instance *instance,
struct in6_addr *src,
struct in6_addr *dst)
{
struct net_rpl_dag *dag = instance->current_dag;
struct in6_addr addr, *dst_addr;
struct net_buf *buf;
uint16_t value;
int ret;
buf = net_nbuf_get_reserve_tx(0);
if (!buf) {
return -ENOMEM;
}
if (!dst) {
net_rpl_create_mcast_address(&addr);
dst_addr = &addr;
} else {
dst_addr = dst;
}
buf = net_ipv6_create_raw(buf, net_if_get_ll_reserve(iface, dst),
src, dst_addr, iface, IPPROTO_ICMPV6);
net_nbuf_set_iface(buf, iface);
net_nbuf_set_ll_reserve(buf, net_if_get_ll_reserve(iface, dst));
setup_icmpv6_hdr(buf, NET_ICMPV6_RPL, NET_RPL_DODAG_INFO_OBJ);
net_nbuf_append_u8(buf, instance->instance_id);
net_nbuf_append_u8(buf, dag->version);
net_nbuf_append_be16(buf, dag->rank);
value = net_rpl_dag_is_grounded(dag) << 8;
value |= instance->mop << NET_RPL_DIO_MOP_SHIFT;
value |= net_rpl_dag_get_preference(dag) & NET_RPL_DIO_PREFERENCE_MASK;
net_nbuf_append_u8(buf, value);
net_nbuf_append_u8(buf, instance->dtsn);
if (!dst) {
net_rpl_lollipop_increment(&instance->dtsn);
}
/* Flags and reserved are set to 0 */
net_nbuf_append_be16(buf, 0);
net_nbuf_append(buf, sizeof(struct in6_addr), dag->dag_id.s6_addr);
if (instance->mc.type != NET_RPL_MC_NONE) {
net_rpl_of_update_mc(instance);
net_nbuf_append_u8(buf, NET_RPL_OPTION_DAG_METRIC_CONTAINER);
net_nbuf_append_u8(buf, 6);
net_nbuf_append_u8(buf, instance->mc.type);
net_nbuf_append_u8(buf, instance->mc.flags >> 1);
value = (instance->mc.flags & 1) << 7;
net_nbuf_append_u8(buf, value |
(instance->mc.aggregated << 4) |
instance->mc.precedence);
if (instance->mc.type == NET_RPL_MC_ETX) {
net_nbuf_append_u8(buf, 2);
net_nbuf_append_be16(buf, instance->mc.obj.etx);
} else if (instance->mc.type == NET_RPL_MC_ENERGY) {
net_nbuf_append_u8(buf, 2);
net_nbuf_append_u8(buf, instance->mc.obj.energy.flags);
net_nbuf_append_u8(buf,
instance->mc.obj.energy.estimation);
} else {
NET_DBG("Cannot send DIO, unknown DAG MC type %u",
instance->mc.type);
net_nbuf_unref(buf);
return -EINVAL;
}
}
net_nbuf_append_u8(buf, NET_RPL_OPTION_DAG_CONF);
net_nbuf_append_u8(buf, 14);
net_nbuf_append_u8(buf, 0); /* No Auth */
net_nbuf_append_u8(buf, instance->dio_interval_doublings);
net_nbuf_append_u8(buf, instance->dio_interval_min);
net_nbuf_append_u8(buf, instance->dio_redundancy);
net_nbuf_append_be16(buf, instance->max_rank_inc);
net_nbuf_append_be16(buf, instance->min_hop_rank_inc);
net_nbuf_append_be16(buf, instance->ocp);
net_nbuf_append_u8(buf, 0); /* Reserved */
net_nbuf_append_u8(buf, instance->default_lifetime);
net_nbuf_append_be16(buf, instance->lifetime_unit);
if (dag->prefix_info.length > 0) {
net_nbuf_append_u8(buf, NET_RPL_OPTION_PREFIX_INFO);
net_nbuf_append_u8(buf, 30); /* length */
net_nbuf_append_u8(buf, dag->prefix_info.length);
net_nbuf_append_u8(buf, dag->prefix_info.flags);
/* First valid lifetime and the second one is
* preferred lifetime.
*/
net_nbuf_append_be32(buf, dag->prefix_info.lifetime);
net_nbuf_append_be32(buf, dag->prefix_info.lifetime);
net_nbuf_append_be32(buf, 0); /* reserved */
net_nbuf_append(buf, sizeof(struct in6_addr),
dag->prefix_info.prefix.s6_addr);
NET_DBG("Sending prefix info in DIO for %s",
net_sprint_ipv6_addr(&dag->prefix_info.prefix));
} else {
NET_DBG("Prefix info not sent because length was %d",
dag->prefix_info.length);
}
buf = net_ipv6_finalize_raw(buf, IPPROTO_ICMPV6);
ret = net_send_data(buf);
if (ret >= 0) {
if (!dst) {
NET_DBG("Sent a multicast DIO with rank %d",
instance->current_dag->rank);
} else {
NET_DBG("Sent a unicast DIO with rank %d to %s",
instance->current_dag->rank,
net_sprint_ipv6_addr(dst));
}
NET_STATS_RPL(++net_stats.icmp.sent);
NET_STATS_RPL(++net_stats.rpl.dio.sent);
return 0;
}
net_nbuf_unref(buf);
return ret;
}
#define DIO_TIMEOUT (MSEC_PER_SEC)
static void dio_timer(struct k_work *work)
{
struct net_rpl_instance *instance = CONTAINER_OF(work,
struct net_rpl_instance,
dio_timer);
NET_DBG("DIO Timer triggered at %u", k_uptime_get_32());
if (!rpl_dio_send_ok) {
struct in6_addr *tmp;
tmp = net_if_ipv6_get_ll_addr(NET_ADDR_PREFERRED, NULL);
if (tmp) {
rpl_dio_send_ok = true;
} else {
NET_DBG("Sending DIO later because IPv6 link local "
"address is not found");
k_delayed_work_submit(&instance->dio_timer,
DIO_TIMEOUT);
return;
}
}
if (instance->dio_send) {
if (instance->dio_redundancy &&
instance->dio_counter < instance->dio_redundancy) {
struct net_if *iface;
struct in6_addr *addr =
net_if_ipv6_get_ll_addr(NET_ADDR_PREFERRED,
&iface);
net_rpl_dio_send(iface, instance, addr, NULL);
#if defined(CONFIG_NET_RPL_STATS)
instance->dio_send_pkt++;
#endif
} else {
NET_DBG("Supressing DIO transmission as %d >= %d",
instance->dio_counter,
instance->dio_redundancy);
}
instance->dio_send = false;
NET_DBG("Next DIO send after %lu ms",
instance->dio_next_delay);
k_delayed_work_submit(&instance->dio_timer,
instance->dio_next_delay);
} else {
if (instance->dio_interval_current <
instance->dio_interval_min +
instance->dio_interval_doublings) {
instance->dio_interval_current++;
NET_DBG("DIO Timer interval doubled to %d",
instance->dio_interval_current);
}
new_dio_interval(instance);
}
net_rpl_print_neighbors();
}
static void new_dio_interval(struct net_rpl_instance *instance)
{
uint32_t time;
time = 1 << instance->dio_interval_current;
NET_ASSERT(time);
instance->dio_next_delay = time;
time = time / 2 + (time / 2 * sys_rand32_get()) / UINT32_MAX;
/* Adjust the interval so that they are equally long among the nodes.
* This is needed so that Trickle algo can operate efficiently.
*/
instance->dio_next_delay -= time;
#if defined(CONFIG_NET_RPL_STATS)
instance->dio_intervals++;
instance->dio_recv_pkt += instance->dio_counter;
NET_DBG("rank %u.%u (%u) stats %d/%d/%d/%d %s",
NET_RPL_DAG_RANK(instance->current_dag->rank, instance),
((10 * (instance->current_dag->rank %
instance->min_hop_rank_inc)) /
instance->min_hop_rank_inc),
instance->current_dag->version,
instance->dio_intervals,
instance->dio_send_pkt,
instance->dio_recv_pkt,
instance->dio_interval_current,
instance->current_dag->rank == NET_RPL_ROOT_RANK(instance) ?
"ROOT" : "");
#endif /* CONFIG_NET_RPL_STATS */
instance->dio_counter = 0;
instance->dio_send = true;
NET_DBG("DIO Timer interval set to %d", time);
k_delayed_work_cancel(&instance->dio_timer);
k_delayed_work_init(&instance->dio_timer, dio_timer);
k_delayed_work_submit(&instance->dio_timer, time);
}
static void net_rpl_dio_reset_timer(struct net_rpl_instance *instance)
{
if (instance->dio_interval_current > instance->dio_interval_min) {
instance->dio_interval_current = instance->dio_interval_min;
instance->dio_counter = 0;
new_dio_interval(instance);
}
NET_STATS_RPL(net_stats.rpl.resets++);
}
static inline void send_dis_all_interfaces(struct net_if *iface,
void *user_data)
{
net_rpl_dis_send(user_data, iface);
}
int net_rpl_dis_send(struct in6_addr *dst, struct net_if *iface)
{
struct in6_addr addr, *dst_addr;
const struct in6_addr *src;
struct net_buf *buf;
uint16_t pos;
int ret;
if (!iface) {
/* Go through all interface to send the DIS */
net_if_foreach(send_dis_all_interfaces,
dst);
return 0;
}
buf = net_nbuf_get_reserve_tx(0);
if (!buf) {
return -ENOMEM;
}
if (!dst) {
net_rpl_create_mcast_address(&addr);
dst_addr = &addr;
} else {
dst_addr = dst;
}
src = net_if_ipv6_select_src_addr(iface, dst_addr);
buf = net_ipv6_create_raw(buf, net_if_get_ll_reserve(iface, dst_addr),
src, dst_addr, iface, IPPROTO_ICMPV6);
net_nbuf_set_iface(buf, iface);
net_nbuf_set_ll_reserve(buf, net_if_get_ll_reserve(iface, dst_addr));
setup_icmpv6_hdr(buf, NET_ICMPV6_RPL, NET_RPL_DODAG_SOLICIT);
/* Add flags and reserved fields */
net_nbuf_write_u8(buf, buf->frags,
sizeof(struct net_ipv6_hdr) +
sizeof(struct net_icmp_hdr),
&pos, 0);
net_nbuf_write_u8(buf, buf->frags, pos, &pos, 0);
buf = net_ipv6_finalize_raw(buf, IPPROTO_ICMPV6);
ret = net_send_data(buf);
if (ret >= 0) {
NET_DBG("Sent a %s DIS to %s", dst ? "unicast" : "multicast",
net_sprint_ipv6_addr(dst_addr));
NET_STATS_RPL(++net_stats.icmp.sent);
NET_STATS_RPL_DIS(++net_stats.rpl.dis.sent);
} else {
net_nbuf_unref(buf);
}
return ret;
}
static enum net_verdict handle_dis(struct net_buf *buf)
{
struct net_rpl_instance *instance;
net_rpl_info(buf, "DODAG Information Solicitation");
for (instance = &rpl_instances[0];
instance < &rpl_instances[0] + CONFIG_NET_RPL_MAX_INSTANCES;
instance++) {
if (!instance->is_used) {
continue;
}
if (net_is_ipv6_addr_mcast(&NET_IPV6_BUF(buf)->dst)) {
net_rpl_dio_reset_timer(instance);
} else {
net_rpl_dio_send(net_nbuf_iface(buf),
instance,
&NET_IPV6_BUF(buf)->src,
&NET_IPV6_BUF(buf)->dst);
}
}
return NET_DROP;
}
static struct net_rpl_instance *net_rpl_get_instance(uint8_t instance_id)
{
int i;
for (i = 0; i < CONFIG_NET_RPL_MAX_INSTANCES; ++i) {
if (rpl_instances[i].is_used &&
rpl_instances[i].instance_id == instance_id) {
return &rpl_instances[i];
}
}
return NULL;
}
#if defined(CONFIG_NET_RPL_PROBING)
#if !defined(NET_RPL_PROBING_INTERVAL)
#define NET_RPL_PROBING_INTERVAL (120 * MSEC_PER_SEC)
#endif
#if !defined(NET_RPL_PROBING_EXPIRATION_TIME)
#define NET_RPL_PROBING_EXPIRATION_TIME ((10 * 60) * MSEC_PER_SEC)
#endif
static void net_rpl_schedule_probing(struct net_rpl_instance *instance);
static struct net_rpl_parent *get_probing_target(struct net_rpl_dag *dag)
{
/* Returns the next probing target. The probes are sent to the current
* preferred parent if we have not updated its link for
* NET_RPL_PROBING_EXPIRATION_TIME.
* Otherwise, it picks at random between:
* (1) selecting the best parent not updated
* for NET_RPL_PROBING_EXPIRATION_TIME
* (2) selecting the least recently updated parent
*/
struct net_rpl_parent *probing_target = NULL;
uint16_t probing_target_rank = NET_RPL_INFINITE_RANK;
/* min_last_tx is the clock time NET_RPL_PROBING_EXPIRATION_TIME in
* the past
*/
uint32_t min_last_tx = k_uptime_get_32();
struct net_rpl_parent *parent;
int i;
min_last_tx = min_last_tx > 2 *
(NET_RPL_PROBING_EXPIRATION_TIME ?
min_last_tx - NET_RPL_PROBING_EXPIRATION_TIME : 1);
if (!dag || !dag->instance || !dag->preferred_parent) {
return NULL;
}
/* Our preferred parent needs probing */
if (dag->preferred_parent->last_tx_time < min_last_tx) {
probing_target = dag->preferred_parent;
}
/* With 50% probability: probe best parent not updated
* for NET_RPL_PROBING_EXPIRATION_TIME
*/
if (!probing_target && (sys_rand32_get() % 2) == 0) {
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
parent = nbr_data(nbr);
if (parent->dag == dag &&
parent->last_tx_time < min_last_tx) {
/* parent is in our dag and needs probing */
uint16_t parent_rank =
net_rpl_of_calc_rank(parent, 0);
if (!probing_target ||
parent_rank < probing_target_rank) {
probing_target = parent;
probing_target_rank = parent_rank;
}
}
}
}
/* The default probing target is the least recently updated parent */
if (!probing_target) {
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
parent = nbr_data(nbr);
if (parent->dag == dag) {
if (!probing_target ||
parent->last_tx_time <
probing_target->last_tx_time) {
probing_target = parent;
}
}
}
}
return probing_target;
}
static void rpl_probing_timer(struct k_work *work)
{
struct net_rpl_instance *instance =
CONTAINER_OF(work, struct net_rpl_instance, probing_timer);
struct net_rpl_parent *probing_target =
get_probing_target(instance->current_dag);
NET_DBG("Probing target %p dag %p", probing_target,
instance->current_dag);
if (probing_target) {
struct net_nbr *nbr = net_rpl_get_nbr(probing_target);
struct net_linkaddr_storage *lladdr;
struct in6_addr *src;
struct in6_addr *dst;
int ret;
dst = net_ipv6_nbr_lookup_by_index(instance->iface, nbr->idx);
lladdr = net_nbr_get_lladdr(nbr->idx);
NET_DBG("Probing %s [%s]", net_sprint_ipv6_addr(dst),
net_sprint_ll_addr(lladdr->addr, lladdr->len));
src = (struct in6_addr *)
net_if_ipv6_select_src_addr(instance->iface, dst);
/* Send probe (currently DIO) */
ret = net_rpl_dio_send(instance->iface, instance, src, dst);
if (ret) {
NET_DBG("DIO probe failed (%d)", ret);
}
}
/* Schedule next probing */
net_rpl_schedule_probing(instance);
net_rpl_print_neighbors();
}
static void net_rpl_schedule_probing(struct net_rpl_instance *instance)
{
int expiration;
expiration = ((NET_RPL_PROBING_INTERVAL / 2) +
sys_rand32_get() % NET_RPL_PROBING_INTERVAL) *
MSEC_PER_SEC;
NET_DBG("Send probe in %lu ms, instance %p (%d)",
expiration, instance, instance->instance_id);
k_delayed_work_init(&instance->probing_timer, rpl_probing_timer);
k_delayed_work_submit(&instance->probing_timer, expiration);
}
#endif /* CONFIG_NET_RPL_PROBING */
static struct net_rpl_instance *net_rpl_alloc_instance(uint8_t instance_id)
{
int i;
for (i = 0; i < CONFIG_NET_RPL_MAX_INSTANCES; ++i) {
if (rpl_instances[i].is_used) {
continue;
}
memset(&rpl_instances[i], 0, sizeof(struct net_rpl_instance));
rpl_instances[i].instance_id = instance_id;
rpl_instances[i].default_route = NULL;
rpl_instances[i].is_used = true;
#if defined(CONFIG_NET_RPL_PROBING)
net_rpl_schedule_probing(&rpl_instances[i]);
#endif
return &rpl_instances[i];
}
return NULL;
}
static struct net_rpl_dag *alloc_dag(uint8_t instance_id,
struct in6_addr *dag_id)
{
struct net_rpl_instance *instance;
struct net_rpl_dag *dag;
int i;
instance = net_rpl_get_instance(instance_id);
if (!instance) {
instance = net_rpl_alloc_instance(instance_id);
if (!instance) {
NET_DBG("Cannot allocate instance id %d", instance_id);
NET_STATS_RPL(net_stats.rpl.mem_overflows++);
return NULL;
}
}
for (i = 0; i < CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE; ++i) {
dag = &instance->dags[i];
if (net_rpl_dag_is_used(dag)) {
continue;
}
memset(dag, 0, sizeof(*dag));
net_rpl_dag_set_used(dag);
dag->rank = NET_RPL_INFINITE_RANK;
dag->min_rank = NET_RPL_INFINITE_RANK;
dag->instance = instance;
return dag;
}
return NULL;
}
static struct net_rpl_dag *get_dag(uint8_t instance_id,
struct in6_addr *dag_id)
{
struct net_rpl_instance *instance;
struct net_rpl_dag *dag;
int i;
instance = net_rpl_get_instance(instance_id);
if (!instance) {
NET_DBG("Cannot get instance id %d", instance_id);
return NULL;
}
for (i = 0; i < CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE; ++i) {
dag = &instance->dags[i];
if (net_rpl_dag_is_used(dag) &&
net_ipv6_addr_cmp(&dag->dag_id, dag_id)) {
return dag;
}
}
return NULL;
}
static void route_rm_cb(struct net_route_entry *entry, void *user_data)
{
struct net_rpl_dag *dag = user_data;
struct net_rpl_route_entry *extra;
extra = net_nbr_extra_data(net_route_get_nbr(entry));
if (extra->dag == dag) {
net_route_del(entry);
}
}
#if NET_RPL_MULTICAST
static void route_mcast_rm_cb(struct net_route_entry_mcast *route,
void *user_data)
{
struct net_rpl_dag *dag = user_data;
struct net_rpl_route_entry *extra;
extra = net_nbr_extra_data(net_route_get_nbr(entry));
if (extra->dag == dag) {
net_route_mcast_del(route)
}
}
#endif
static void net_rpl_remove_routes(struct net_rpl_dag *dag)
{
net_route_foreach(route_rm_cb, dag);
#if NET_RPL_MULTICAST
net_route_mcast_foreach(route_mcast_rm_cb, dag);
#endif
}
static inline void set_ip_from_prefix(struct net_linkaddr *lladdr,
struct net_rpl_prefix *prefix,
struct in6_addr *addr)
{
memset(addr, 0, sizeof(struct in6_addr));
net_ipv6_addr_create_iid(addr, lladdr);
memcpy(addr->s6_addr, &prefix->prefix, (prefix->length + 7) / 8);
}
static void check_prefix(struct net_if *iface,
struct net_rpl_prefix *last_prefix,
struct net_rpl_prefix *new_prefix)
{
struct in6_addr addr;
if (last_prefix && new_prefix &&
last_prefix->length == new_prefix->length &&
net_is_ipv6_prefix(last_prefix->prefix.s6_addr,
new_prefix->prefix.s6_addr,
new_prefix->length) &&
last_prefix->flags == new_prefix->flags) {
/* Nothing has changed. */
NET_DBG("Same prefix %s/%d flags 0x%x",
net_sprint_ipv6_addr(&new_prefix->prefix),
new_prefix->length, new_prefix->flags);
return;
}
if (last_prefix) {
set_ip_from_prefix(&iface->link_addr, last_prefix, &addr);
if (net_if_ipv6_addr_rm(iface, &addr)) {
NET_DBG("Removed global IP address %s",
net_sprint_ipv6_addr(&addr));
}
}
if (new_prefix) {
set_ip_from_prefix(&iface->link_addr, new_prefix, &addr);
if (net_if_ipv6_addr_add(iface, &addr, NET_ADDR_AUTOCONF, 0)) {
NET_DBG("Added global IP address %s",
net_sprint_ipv6_addr(&addr));
}
}
}
static void net_rpl_free_dag(struct net_if *iface, struct net_rpl_dag *dag)
{
if (net_rpl_dag_is_joined(dag)) {
NET_DBG("Leaving the DAG %s",
net_sprint_ipv6_addr(&dag->dag_id));
net_rpl_dag_unjoin(dag);
/* Remove routes installed by DAOs. */
net_rpl_remove_routes(dag);
/* Remove autoconfigured address */
if ((dag->prefix_info.flags & NET_ICMPV6_RA_FLAG_AUTONOMOUS)) {
check_prefix(iface, &dag->prefix_info, NULL);
}
remove_parents(iface, dag, 0);
}
net_rpl_dag_set_not_used(dag);
}
static void net_rpl_set_preferred_parent(struct net_if *iface,
struct net_rpl_dag *dag,
struct net_rpl_parent *parent)
{
if (dag && dag->preferred_parent != parent) {
struct in6_addr *addr = net_rpl_get_parent_addr(iface, parent);
NET_DBG("Preferred parent %s",
parent ? net_sprint_ipv6_addr(addr) : "not set");
addr = net_rpl_get_parent_addr(iface, dag->preferred_parent);
NET_DBG("It used to be %s",
dag->preferred_parent ?
net_sprint_ipv6_addr(addr) : "not set");
dag->preferred_parent = parent;
}
}
static void net_rpl_reset_dio_timer(struct net_rpl_instance *instance)
{
NET_DBG("instance %p current %d min %d", instance,
instance->dio_interval_current,
instance->dio_interval_min);
/* Do not reset if we are already on the minimum interval,
* unless forced to do so.
*/
if (instance->dio_interval_current > instance->dio_interval_min) {
instance->dio_counter = 0;
instance->dio_interval_current = instance->dio_interval_min;
new_dio_interval(instance);
}
NET_STATS_RPL(net_stats.rpl.resets++);
}
static
struct net_rpl_dag *net_rpl_set_root_with_version(struct net_if *iface,
uint8_t instance_id,
struct in6_addr *dag_id,
uint8_t version)
{
struct net_rpl_dag *dag;
struct net_rpl_instance *instance;
int i;
instance = net_rpl_get_instance(instance_id);
if (instance) {
for (i = 0; i < CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE; i++) {
dag = &instance->dags[i];
if (net_rpl_dag_is_used(dag)) {
if (net_ipv6_addr_cmp(&dag->dag_id, dag_id)) {
version = dag->version;
net_rpl_lollipop_increment(&version);
}
if (dag == dag->instance->current_dag) {
NET_DBG("Dropping a joined DAG when "
"setting this node as root");
dag->instance->current_dag = NULL;
} else {
NET_DBG("Dropping a DAG when "
"setting this node as root");
}
net_rpl_free_dag(iface, dag);
}
}
}
dag = alloc_dag(instance_id, dag_id);
if (!dag) {
NET_DBG("Failed to allocate a DAG");
return NULL;
}
instance = dag->instance;
net_rpl_dag_join(dag);
net_rpl_dag_set_preference(dag, CONFIG_NET_RPL_PREFERENCE);
net_rpl_dag_set_grounded_status(dag, NET_RPL_GROUNDED);
dag->version = version;
instance->mop = NET_RPL_MOP_DEFAULT;
instance->ocp = net_rpl_of_get();
net_rpl_set_preferred_parent(iface, dag, NULL);
net_ipaddr_copy(&dag->dag_id, dag_id);
instance->dio_interval_doublings =
CONFIG_NET_RPL_DIO_INTERVAL_DOUBLINGS;
instance->dio_interval_min = CONFIG_NET_RPL_DIO_INTERVAL_MIN;
/* The current interval must differ from the minimum interval in
* order to trigger a DIO timer reset.
*/
instance->dio_interval_current = CONFIG_NET_RPL_DIO_INTERVAL_MIN +
CONFIG_NET_RPL_DIO_INTERVAL_DOUBLINGS;
instance->dio_redundancy = CONFIG_NET_RPL_DIO_REDUNDANCY;
instance->max_rank_inc = NET_RPL_MAX_RANK_INC;
instance->min_hop_rank_inc = CONFIG_NET_RPL_MIN_HOP_RANK_INC;
instance->default_lifetime = CONFIG_NET_RPL_DEFAULT_LIFETIME;
instance->lifetime_unit = CONFIG_NET_RPL_DEFAULT_LIFETIME_UNIT;
dag->rank = NET_RPL_ROOT_RANK(instance);
if (instance->current_dag != dag && instance->current_dag) {
/* Remove routes installed by DAOs. */
net_rpl_remove_routes(instance->current_dag);
net_rpl_dag_unjoin(instance->current_dag);
}
instance->current_dag = dag;
instance->dtsn = net_rpl_lollipop_init();
net_rpl_of_update_mc(instance);
rpl_default_instance = instance;
NET_DBG("Node set to be a DAG root with DAG ID %s",
net_sprint_ipv6_addr(&dag->dag_id));
net_rpl_reset_dio_timer(instance);
return dag;
}
struct net_rpl_dag *net_rpl_get_any_dag(void)
{
int i;
for (i = 0; i < CONFIG_NET_RPL_MAX_INSTANCES; ++i) {
if (rpl_instances[i].is_used &&
net_rpl_dag_is_joined(rpl_instances[i].current_dag)) {
return rpl_instances[i].current_dag;
}
}
return NULL;
}
struct net_rpl_dag *net_rpl_set_root(struct net_if *iface,
uint8_t instance_id,
struct in6_addr *dag_id)
{
return net_rpl_set_root_with_version(iface, instance_id, dag_id,
net_rpl_lollipop_init());
}
static int lollipop_greater_than(int a, int b)
{
/* Check if we are comparing an initial value with an old value */
if (a > NET_RPL_LOLLIPOP_CIRCULAR_REGION &&
b <= NET_RPL_LOLLIPOP_CIRCULAR_REGION) {
return (NET_RPL_LOLLIPOP_MAX_VALUE + 1 + b - a) >
NET_RPL_LOLLIPOP_SEQUENCE_WINDOWS;
}
/* Otherwise check if a > b and comparable => ok, or
* if they have wrapped and are still comparable
*/
return (a > b && (a - b) < NET_RPL_LOLLIPOP_SEQUENCE_WINDOWS) ||
(a < b && (b - a) > (NET_RPL_LOLLIPOP_CIRCULAR_REGION + 1 -
NET_RPL_LOLLIPOP_SEQUENCE_WINDOWS));
}
bool net_rpl_set_prefix(struct net_if *iface,
struct net_rpl_dag *dag,
struct in6_addr *prefix,
uint8_t prefix_len)
{
uint8_t last_len = dag->prefix_info.length;
struct net_rpl_prefix last_prefix;
if (prefix_len > 128) {
return false;
}
if (dag->prefix_info.length) {
memcpy(&last_prefix, &dag->prefix_info,
sizeof(struct net_rpl_prefix));
}
memset(&dag->prefix_info.prefix, 0,
sizeof(dag->prefix_info.prefix));
memcpy(&dag->prefix_info.prefix, prefix, (prefix_len + 7) / 8);
dag->prefix_info.length = prefix_len;
dag->prefix_info.flags = NET_ICMPV6_RA_FLAG_AUTONOMOUS;
/* Autoconfigure an address if this node does not already have
* an address with this prefix. Otherwise, update the prefix.
*/
NET_DBG("Prefix is %s, will announce this in DIOs",
last_len ? "non-NULL" : "NULL");
if (last_len == 0) {
check_prefix(iface, NULL, &dag->prefix_info);
} else {
check_prefix(iface, &last_prefix, &dag->prefix_info);
}
return true;
}
static void net_rpl_nullify_parent(struct net_if *iface,
struct net_rpl_parent *parent)
{
struct net_rpl_dag *dag = parent->dag;
#if NET_DEBUG
struct in6_addr *addr = net_rpl_get_parent_addr(iface, parent);
#endif
/* This function can be called when the preferred parent is NULL,
* so we need to handle this condition properly.
*/
if (parent == dag->preferred_parent || !dag->preferred_parent) {
dag->rank = NET_RPL_INFINITE_RANK;
if (net_rpl_dag_is_joined(dag)) {
if (dag->instance->default_route) {
NET_DBG("Removing default route %s",
net_sprint_ipv6_addr(addr));
net_if_router_rm(dag->instance->default_route);
dag->instance->default_route = NULL;
}
/* Send no-path DAO only to preferred parent, if any */
if (parent == dag->preferred_parent) {
dao_send(parent, NET_RPL_ZERO_LIFETIME, NULL);
net_rpl_set_preferred_parent(iface, dag, NULL);
}
}
}
NET_DBG("Nullifying parent %s", net_sprint_ipv6_addr(addr));
}
static void net_rpl_remove_parent(struct net_if *iface,
struct net_rpl_parent *parent,
struct net_nbr *nbr)
{
if (!nbr) {
nbr = net_rpl_get_nbr(parent);
}
NET_ASSERT(iface);
if (nbr) {
#if NET_DEBUG
struct in6_addr *addr;
struct net_linkaddr_storage *lladdr;
addr = net_rpl_get_parent_addr(iface, parent);
lladdr = net_nbr_get_lladdr(nbr->idx);
NET_DBG("Removing parent %s [%s]",
net_sprint_ipv6_addr(addr),
net_sprint_ll_addr(lladdr->addr, lladdr->len));
#endif
net_rpl_nullify_parent(iface, parent);
nbr_free(nbr);
}
}
/* Remove DAG parents with a rank that is at least the same as minimum_rank.
*/
static void remove_parents(struct net_if *iface,
struct net_rpl_dag *dag,
uint16_t minimum_rank)
{
int i;
NET_DBG("Removing parents minimum rank %u", minimum_rank);
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
struct net_rpl_parent *parent;
parent = nbr_data(nbr);
if (dag == parent->dag && parent->rank >= minimum_rank) {
net_rpl_remove_parent(iface, parent, nbr);
}
}
}
static struct net_rpl_parent *net_rpl_add_parent(struct net_if *iface,
struct net_rpl_dag *dag,
struct net_rpl_dio *dio,
struct in6_addr *addr)
{
struct net_nbr *nbr;
/* Is the parent known in neighbor cache? Drop this request if not.
* Typically, the parent is added upon receiving a DIO.
*/
nbr = net_ipv6_nbr_lookup(iface, addr);
if (nbr) {
struct net_linkaddr_storage *lladdr_storage;
struct net_ipv6_nbr_data *data;
struct net_rpl_parent *parent;
struct net_linkaddr lladdr;
struct net_nbr *rpl_nbr;
lladdr_storage = net_nbr_get_lladdr(nbr->idx);
lladdr.addr = lladdr_storage->addr;
lladdr.len = lladdr_storage->len;
rpl_nbr = net_nbr_lookup(&net_rpl_parents.table,
iface,
&lladdr);
if (!rpl_nbr) {
NET_DBG("Add parent %s [%s]",
net_sprint_ipv6_addr(addr),
net_sprint_ll_addr(lladdr.addr, lladdr.len));
rpl_nbr = nbr_add(iface, addr, &lladdr);
if (!rpl_nbr) {
NET_DBG("Cannot add RPL neighbor");
return NULL;
}
}
parent = nbr_data(rpl_nbr);
NET_DBG("[%d] nbr %p parent %p", rpl_nbr->idx, rpl_nbr,
parent);
parent->dag = dag;
parent->rank = dio->rank;
parent->dtsn = dio->dtsn;
/* Check whether we have a neighbor that has not gotten
* a link metric yet.
*/
data = net_ipv6_nbr_data(nbr);
if (data->link_metric == 0) {
data->link_metric = CONFIG_NET_RPL_INIT_LINK_METRIC *
NET_RPL_MC_ETX_DIVISOR;
}
#if !defined(CONFIG_NET_RPL_DAG_MC_NONE)
memcpy(&parent->mc, &dio->mc, sizeof(parent->mc));
#endif
return parent;
}
return NULL;
}
static void dao_timer(struct net_rpl_instance *instance)
{
/* Send the DAO to the preferred parent. */
if (instance->current_dag->preferred_parent) {
NET_DBG("Sending DAO iface %p", instance->iface);
dao_send(instance->current_dag->preferred_parent,
instance->default_lifetime,
instance->iface);
#if NET_RPL_MULTICAST
/* Send DAOs for multicast prefixes only if the instance is
* in MOP 3.
*/
if (instance->mop == NET_RPL_MOP_STORING_MULTICAST) {
send_mcast_dao(instance);
}
#endif
} else {
NET_DBG("No suitable DAO parent found.");
}
}
static void dao_lifetime_timer(struct k_work *work)
{
struct net_rpl_instance *instance =
CONTAINER_OF(work, struct net_rpl_instance,
dao_lifetime_timer);
dao_timer(instance);
instance->dao_lifetime_timer_active = false;
set_dao_lifetime_timer(instance);
}
static void set_dao_lifetime_timer(struct net_rpl_instance *instance)
{
if (net_rpl_get_mode() == NET_RPL_MODE_FEATHER) {
return;
}
/* Set up another DAO within half the expiration time,
* if such a time has been configured.
*/
if (instance && instance->lifetime_unit != 0xffff &&
instance->default_lifetime != 0xff) {
uint32_t expiration_time;
expiration_time = (uint32_t)instance->default_lifetime *
(uint32_t)instance->lifetime_unit *
MSEC_PER_SEC / 2;
instance->dao_lifetime_timer_active = true;
NET_DBG("Scheduling DAO lifetime timer %d ms in the future",
expiration_time);
k_delayed_work_init(&instance->dao_lifetime_timer,
dao_lifetime_timer);
k_delayed_work_submit(&instance->dao_lifetime_timer,
expiration_time);
}
}
static void dao_send_timer(struct k_work *work)
{
struct net_rpl_instance *instance =
CONTAINER_OF(work, struct net_rpl_instance, dao_timer);
instance->dao_timer_active = false;
if (!rpl_dio_send_ok &&
!net_if_ipv6_get_ll(instance->iface, NET_ADDR_PREFERRED)) {
NET_DBG("Postpone DAO transmission, trying again later.");
instance->dao_timer_active = true;
k_delayed_work_submit(&instance->dao_timer, MSEC_PER_SEC);
return;
}
dao_timer(instance);
}
static void schedule_dao(struct net_rpl_instance *instance, int latency)
{
int expiration;
if (net_rpl_get_mode() == NET_RPL_MODE_FEATHER) {
return;
}
if (instance->dao_timer_active) {
NET_DBG("DAO timer already scheduled");
return;
}
if (latency != 0) {
latency = latency * MSEC_PER_SEC;
expiration = latency / 2 + (sys_rand32_get() % latency);
} else {
expiration = 0;
}
NET_DBG("Scheduling DAO timer %u ms in the future",
(unsigned int)expiration);
instance->dao_timer_active = true;
k_delayed_work_init(&instance->dao_timer, dao_send_timer);
k_delayed_work_submit(&instance->dao_timer, expiration);
if (!instance->dao_lifetime_timer_active) {
set_dao_lifetime_timer(instance);
}
}
static inline void net_rpl_schedule_dao(struct net_rpl_instance *instance)
{
schedule_dao(instance, CONFIG_NET_RPL_DAO_TIMER);
}
static inline void net_rpl_schedule_dao_now(struct net_rpl_instance *instance)
{
schedule_dao(instance, 0);
}
static int net_rpl_set_default_route(struct net_if *iface,
struct net_rpl_instance *instance,
struct in6_addr *from)
{
if (instance->default_route) {
NET_DBG("Removing default route through %s",
net_sprint_ipv6_addr(&instance->default_route->address.
in6_addr));
net_if_router_rm(instance->default_route);
instance->default_route = NULL;
}
if (from) {
NET_DBG("Adding default route through %s",
net_sprint_ipv6_addr(from));
instance->default_route =
net_if_ipv6_router_add(iface, from,
net_rpl_lifetime(instance,
instance->default_lifetime));
if (!instance->default_route) {
return -EINVAL;
}
} else {
if (instance->default_route) {
NET_DBG("Removing default route through %s",
net_sprint_ipv6_addr(&instance->
default_route->address.
in6_addr));
net_if_router_rm(instance->default_route);
instance->default_route = NULL;
} else {
NET_DBG("Not removing default route because it is "
"missing");
}
}
return 0;
}
static inline
struct net_rpl_dag *get_best_dag(struct net_rpl_instance *instance,
struct net_rpl_parent *parent)
{
struct net_rpl_dag *dag, *end, *best_dag = NULL;
for (dag = &instance->dags[0],
end = dag + CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE;
dag < end; ++dag) {
if (dag->is_used && dag->preferred_parent &&
dag->preferred_parent->rank != NET_RPL_INFINITE_RANK) {
if (!best_dag) {
best_dag = dag;
} else {
best_dag = net_rpl_of_best_dag(best_dag,
dag);
}
}
}
return best_dag;
}
static struct net_rpl_parent *best_parent(struct net_if *iface,
struct net_rpl_dag *dag)
{
struct net_rpl_parent *best = NULL;
int i;
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
struct net_rpl_parent *parent;
parent = nbr_data(nbr);
if (parent->dag != dag ||
parent->rank == NET_RPL_INFINITE_RANK) {
/* ignore this neighbor */
} else if (!best) {
best = parent;
} else {
best = net_rpl_of_best_parent(iface, best, parent);
}
}
return best;
}
static struct net_rpl_parent *net_rpl_select_parent(struct net_if *iface,
struct net_rpl_dag *dag)
{
struct net_rpl_parent *best = best_parent(iface, dag);
if (best) {
net_rpl_set_preferred_parent(iface, dag, best);
}
return best;
}
static int acceptable_rank(struct net_rpl_dag *dag, uint16_t rank)
{
return rank != NET_RPL_INFINITE_RANK &&
(dag->instance->max_rank_inc == 0 ||
NET_RPL_DAG_RANK(rank, dag->instance) <=
NET_RPL_DAG_RANK(dag->min_rank + dag->instance->max_rank_inc,
dag->instance));
}
static
struct net_rpl_dag *net_rpl_select_dag(struct net_if *iface,
struct net_rpl_instance *instance,
struct net_rpl_parent *parent)
{
struct net_rpl_parent *last_parent;
struct net_rpl_dag *best_dag;
uint16_t old_rank;
old_rank = instance->current_dag->rank;
last_parent = instance->current_dag->preferred_parent;
best_dag = instance->current_dag;
if (best_dag->rank != NET_RPL_ROOT_RANK(instance)) {
if (net_rpl_select_parent(iface, parent->dag)) {
if (parent->dag != best_dag) {
best_dag = net_rpl_of_best_dag(best_dag,
parent->dag);
}
} else if (parent->dag == best_dag) {
best_dag = get_best_dag(instance, parent);
}
}
if (!best_dag) {
/* No parent found: the calling function handle this problem. */
return NULL;
}
if (instance->current_dag != best_dag) {
/* Remove routes installed by DAOs. */
net_rpl_remove_routes(instance->current_dag);
NET_DBG("New preferred DAG %s",
net_sprint_ipv6_addr(&best_dag->dag_id));
if (best_dag->prefix_info.flags &
NET_ICMPV6_RA_FLAG_AUTONOMOUS) {
check_prefix(iface,
&instance->current_dag->prefix_info,
&best_dag->prefix_info);
} else if (instance->current_dag->prefix_info.flags &
NET_ICMPV6_RA_FLAG_AUTONOMOUS) {
check_prefix(iface,
&instance->current_dag->prefix_info,
NULL);
}
net_rpl_dag_join(best_dag);
net_rpl_dag_unjoin(instance->current_dag);
instance->current_dag = best_dag;
}
net_rpl_of_update_mc(instance);
/* Update the DAG rank. */
best_dag->rank = net_rpl_of_calc_rank(best_dag->preferred_parent, 0);
if (!last_parent || best_dag->rank < best_dag->min_rank) {
best_dag->min_rank = best_dag->rank;
} else if (!acceptable_rank(best_dag, best_dag->rank)) {
NET_DBG("New rank unacceptable!");
net_rpl_set_preferred_parent(iface, instance->current_dag,
NULL);
if (instance->mop != NET_RPL_MOP_NO_DOWNWARD_ROUTES &&
last_parent) {
/* Send a No-Path DAO to the removed preferred parent.
*/
dao_send(last_parent, NET_RPL_ZERO_LIFETIME, iface);
}
return NULL;
}
if (best_dag->preferred_parent != last_parent) {
net_rpl_set_default_route(iface, instance,
net_rpl_get_parent_addr(iface,
best_dag->preferred_parent));
NET_DBG("Changed preferred parent, rank changed from %u to %u",
old_rank, best_dag->rank);
NET_STATS_RPL(net_stats.rpl.parent_switch++);
if (instance->mop != NET_RPL_MOP_NO_DOWNWARD_ROUTES) {
if (last_parent) {
/* Send a No-Path DAO to the removed preferred
* parent.
*/
dao_send(last_parent,
NET_RPL_ZERO_LIFETIME,
iface);
}
/* The DAO parent set changed, so schedule a DAO
* transmission.
*/
net_rpl_lollipop_increment(&instance->dtsn);
net_rpl_schedule_dao(instance);
}
net_rpl_reset_dio_timer(instance);
net_rpl_print_neighbors();
} else if (best_dag->rank != old_rank) {
NET_DBG("Preferred parent update, rank changed from %u to %u",
old_rank, best_dag->rank);
}
return best_dag;
}
static void nullify_parents(struct net_if *iface,
struct net_rpl_dag *dag,
uint16_t minimum_rank)
{
int i;
NET_DBG("Nullifying parents (minimum rank %u)", minimum_rank);
for (i = 0; i < CONFIG_NET_IPV6_MAX_NEIGHBORS; i++) {
struct net_nbr *nbr = get_nbr(i);
struct net_rpl_parent *parent;
parent = nbr_data(nbr);
if (dag == parent->dag &&
parent->rank >= minimum_rank) {
net_rpl_nullify_parent(iface, parent);
}
}
}
static void net_rpl_local_repair(struct net_if *iface,
struct net_rpl_instance *instance)
{
int i;
if (!instance) {
return;
}
NET_DBG("Starting a local instance repair");
for (i = 0; i < CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE; i++) {
if (instance->dags[i].is_used) {
instance->dags[i].rank = NET_RPL_INFINITE_RANK;
nullify_parents(iface, &instance->dags[i], 0);
}
}
net_rpl_reset_dio_timer(instance);
NET_STATS_RPL(net_stats.rpl.local_repairs++);
}
/* Return true if parent is kept, false if it is dropped */
static bool net_rpl_process_parent_event(struct net_if *iface,
struct net_rpl_instance *instance,
struct net_rpl_parent *parent)
{
bool ret = true;
#if NET_DEBUG
uint16_t old_rank = instance->current_dag->rank;
#endif
if (!acceptable_rank(parent->dag, parent->rank)) {
/* The candidate parent is no longer valid: the rank increase
* resulting from the choice of it as a parent would be too
* high.
*/
NET_DBG("Unacceptable rank %u", parent->rank);
net_rpl_nullify_parent(iface, parent);
if (parent != instance->current_dag->preferred_parent) {
return false;
}
ret = false;
}
if (!net_rpl_select_dag(iface, instance, parent)) {
/* No suitable parent; trigger a local repair. */
NET_DBG("No parents found in any DAG");
net_rpl_local_repair(iface, instance);
return false;
}
#if NET_DEBUG
if (NET_RPL_DAG_RANK(old_rank, instance) !=
NET_RPL_DAG_RANK(instance->current_dag->rank, instance)) {
NET_DBG("Moving in the instance from rank %u to %u",
NET_RPL_DAG_RANK(old_rank, instance),
NET_RPL_DAG_RANK(instance->current_dag->rank,
instance));
if (instance->current_dag->rank != NET_RPL_INFINITE_RANK) {
NET_DBG("The preferred parent is %s (rank %u)",
net_sprint_ipv6_addr(
net_rpl_get_parent_addr(iface,
instance->current_dag->
preferred_parent)),
NET_RPL_DAG_RANK(instance->current_dag->
preferred_parent->rank,
instance));
} else {
NET_DBG("We don't have any parent");
}
}
#endif
return ret;
}
static bool net_rpl_repair_root(uint8_t instance_id)
{
struct net_rpl_instance *instance;
instance = net_rpl_get_instance(instance_id);
if (!instance ||
instance->current_dag->rank != NET_RPL_ROOT_RANK(instance)) {
NET_DBG("RPL repair root triggered but not root");
return false;
}
NET_STATS_RPL(net_stats.rpl.root_repairs++);
net_rpl_lollipop_increment(&instance->current_dag->version);
net_rpl_lollipop_increment(&instance->dtsn);
NET_DBG("RPL repair root initiating global repair with version %d",
instance->current_dag->version);
net_rpl_reset_dio_timer(instance);
return true;
}
void net_rpl_global_repair(struct net_route_entry *route)
{
/* Trigger a global repair. */
struct net_rpl_route_entry *extra;
struct net_rpl_instance *instance;
struct net_rpl_dag *dag;
struct net_nbr *nbr;
nbr = net_route_get_nbr(route);
if (!nbr) {
NET_DBG("No neighbor for route %p", route);
return;
}
extra = net_nbr_extra_data(nbr);
dag = extra->dag;
if (dag) {
instance = dag->instance;
net_rpl_repair_root(instance->instance_id);
}
}
static void global_repair(struct net_if *iface,
struct in6_addr *from,
struct net_rpl_dag *dag,
struct net_rpl_dio *dio)
{
struct net_rpl_parent *parent;
remove_parents(iface, dag, 0);
dag->version = dio->version;
/* Copy parts of the configuration so that it propagates
* in the network.
*/
dag->instance->dio_interval_doublings = dio->dag_interval_doublings;
dag->instance->dio_interval_min = dio->dag_interval_min;
dag->instance->dio_redundancy = dio->dag_redundancy;
dag->instance->default_lifetime = dio->default_lifetime;
dag->instance->lifetime_unit = dio->lifetime_unit;
net_rpl_of_reset(dag);
dag->min_rank = NET_RPL_INFINITE_RANK;
net_rpl_lollipop_increment(&dag->instance->dtsn);
parent = net_rpl_add_parent(iface, dag, dio, from);
if (!parent) {
NET_DBG("Failed to add a parent during the global repair");
dag->rank = NET_RPL_INFINITE_RANK;
} else {
dag->rank = net_rpl_of_calc_rank(parent, 0);
dag->min_rank = dag->rank;
NET_DBG("Starting global repair");
net_rpl_process_parent_event(iface, dag->instance, parent);
}
NET_DBG("Participating in a global repair version %d rank %d",
dag->version, dag->rank);
NET_STATS_RPL(net_stats.rpl.global_repairs++);
}
#define net_rpl_print_parent_info(parent, instance) \
do { \
struct net_nbr *nbr; \
struct net_ipv6_nbr_data *data = NULL; \
\
nbr = net_rpl_get_nbr(parent); \
if (nbr->idx != NET_NBR_LLADDR_UNKNOWN) { \
data = net_ipv6_get_nbr_by_index(nbr->idx); \
} \
\
NET_DBG("Preferred DAG %s rank %d min_rank %d " \
"parent rank %d parent etx %d link metric %d " \
"instance etx %d", \
net_sprint_ipv6_addr(&(instance)->current_dag-> \
dag_id), \
(instance)->current_dag->rank, \
(instance)->current_dag->min_rank, \
(parent)->rank, -1, \
data ? data->link_metric : 0, \
(instance)->mc.obj.etx); \
} while (0)
#if NET_RPL_MULTICAST
static void send_mcast_dao(struct net_route_entry_mcast *route,
void *user_data)
{
struct net_rpl_instance *instance = user_data;
/* Don't send if it's also our own address, done that already */
if (!net_route_mcast_lookup(&route->group)) {
net_rpl_dao_send(instance->current_dag->preferred_parent,
&route->group,
CONFIG_NET_RPL_MCAST_LIFETIME);
}
}
static inline void send_mcast_dao(struct net_rpl_instance *instance)
{
uip_mcast6_route_t *mcast_route;
uint8_t i;
/* Send a DAO for own multicast addresses */
for (i = 0; i < NET_IF_MAX_IPV6_MADDR; i++) {
struct in6_addr *addr;
addr = &instance->iface->ipv6.mcast[i].address.in6_addr;
if (instance->iface->ipv6.mcast[i].is_used &&
net_is_ipv6_addr_mcast_global(addr)) {
net_rpl_dao_send(instance->iface,
instance->current_dag->preferred_parent,
addr,
CONFIG_NET_RPL_MCAST_LIFETIME);
}
}
/* Iterate over multicast routes and send DAOs */
net_route_mcast_foreach(send_mcast_dao, addr, instance);
}
#endif
static void net_rpl_join_instance(struct net_if *iface,
struct in6_addr *from,
struct net_rpl_dio *dio)
{
struct net_rpl_instance *instance;
struct net_rpl_parent *parent;
struct net_rpl_dag *dag;
dag = alloc_dag(dio->instance_id, &dio->dag_id);
if (!dag) {
NET_DBG("Failed to allocate a DAG object!");
return;
}
instance = dag->instance;
parent = net_rpl_add_parent(iface, dag, dio, from);
if (!parent) {
instance->is_used = false;
NET_DBG("Cannot add %s as a parent",
net_sprint_ipv6_addr(from));
return;
}
NET_DBG("Add %s as a parent", net_sprint_ipv6_addr(from));
parent->dtsn = dio->dtsn;
/* Determine the objective function by using the objective code point
* of the DIO.
*/
if (!net_rpl_of_find(dio->ocp)) {
NET_DBG("DIO for DAG instance %d does not specify "
"a supported OF", dio->instance_id);
instance->is_used = false;
net_rpl_remove_parent(iface, parent, NULL);
return;
}
/* Autoconfigure an address if this node does not already have
* an address with this prefix.
*/
if (dio->prefix_info.flags & NET_ICMPV6_RA_FLAG_AUTONOMOUS) {
check_prefix(iface, NULL, &dio->prefix_info);
}
net_rpl_dag_join(dag);
net_rpl_dag_set_preference(dag, dio->preference);
net_rpl_dag_set_grounded_status(dag, dio->grounded);
dag->version = dio->version;
instance->ocp = dio->ocp;
instance->mop = dio->mop;
instance->current_dag = dag;
instance->dtsn = net_rpl_lollipop_init();
instance->max_rank_inc = dio->max_rank_inc;
instance->min_hop_rank_inc = dio->min_hop_rank_inc;
instance->dio_interval_doublings = dio->dag_interval_doublings;
instance->dio_interval_min = dio->dag_interval_min;
instance->dio_interval_current =
instance->dio_interval_min + instance->dio_interval_doublings;
instance->dio_redundancy = dio->dag_redundancy;
instance->default_lifetime = dio->default_lifetime;
instance->lifetime_unit = dio->lifetime_unit;
instance->iface = iface;
net_ipaddr_copy(&dag->dag_id, &dio->dag_id);
memcpy(&dag->prefix_info, &dio->prefix_info,
sizeof(struct net_rpl_prefix));
net_rpl_set_preferred_parent(iface, dag, parent);
net_rpl_of_update_mc(instance);
dag->rank = net_rpl_of_calc_rank(parent, 0);
/* So far this is the lowest rank we are aware of. */
dag->min_rank = dag->rank;
if (!rpl_default_instance) {
rpl_default_instance = instance;
}
NET_DBG("Joined DAG with instance ID %d rank %d DAG ID %s",
dio->instance_id, dag->min_rank,
net_sprint_ipv6_addr(&dag->dag_id));
net_rpl_reset_dio_timer(instance);
net_rpl_set_default_route(iface, instance, from);
if (instance->mop != NET_RPL_MOP_NO_DOWNWARD_ROUTES) {
net_rpl_schedule_dao(instance);
} else {
NET_DBG("DIO does not meet the prerequisites for "
"sending a DAO");
}
}
static
struct net_rpl_parent *find_parent_any_dag_any_instance(struct net_if *iface,
struct in6_addr *addr)
{
struct net_nbr *nbr, *rpl_nbr;
nbr = net_ipv6_nbr_lookup(iface, addr);
if (!nbr) {
return NULL;
}
rpl_nbr = nbr_lookup(&net_rpl_parents.table, iface, addr);
if (!rpl_nbr) {
return NULL;
}
return nbr_data(rpl_nbr);
}
static struct net_rpl_parent *find_parent(struct net_if *iface,
struct net_rpl_dag *dag,
struct in6_addr *addr)
{
struct net_rpl_parent *parent;
parent = find_parent_any_dag_any_instance(iface, addr);
if (parent && parent->dag == dag) {
return parent;
}
return NULL;
}
static struct net_rpl_dag *find_parent_dag(struct net_if *iface,
struct net_rpl_instance *instance,
struct in6_addr *addr)
{
struct net_rpl_parent *parent;
parent = find_parent_any_dag_any_instance(iface, addr);
if (parent) {
return parent->dag;
}
return NULL;
}
static
struct net_rpl_parent *find_parent_any_dag(struct net_if *iface,
struct net_rpl_instance *instance,
struct in6_addr *addr)
{
struct net_rpl_parent *parent;
parent = find_parent_any_dag_any_instance(iface, addr);
if (parent && parent->dag && parent->dag->instance == instance) {
return parent;
}
return NULL;
}
static void net_rpl_move_parent(struct net_if *iface,
struct net_rpl_dag *dag_src,
struct net_rpl_dag *dag_dst,
struct net_rpl_parent *parent)
{
struct in6_addr *addr = net_rpl_get_parent_addr(iface, parent);
if (parent == dag_src->preferred_parent) {
net_rpl_set_preferred_parent(iface, dag_src, NULL);
dag_src->rank = NET_RPL_INFINITE_RANK;
if (net_rpl_dag_is_joined(dag_src) &&
dag_src->instance->default_route) {
NET_DBG("Removing default route %s",
net_sprint_ipv6_addr(addr));
net_if_router_rm(dag_src->instance->default_route);
dag_src->instance->default_route = NULL;
}
} else if (net_rpl_dag_is_joined(dag_src)) {
/* Remove routes that have this parent as the next hop and
* which has correct DAG pointer.
*/
net_route_del_by_nexthop_data(iface, addr, dag_src);
}
NET_DBG("Moving parent %s", net_sprint_ipv6_addr(addr));
parent->dag = dag_dst;
}
static void net_rpl_link_neighbor_callback(struct net_if *iface,
struct net_linkaddr *lladdr,
int status)
{
struct net_rpl_instance *instance;
struct in6_addr addr;
net_ipv6_addr_create_iid(&addr, lladdr);
for (instance = &rpl_instances[0];
instance < &rpl_instances[0] + CONFIG_NET_RPL_MAX_INSTANCES;
instance++) {
struct net_rpl_parent *parent;
if (!instance->is_used) {
continue;
}
parent = find_parent_any_dag(iface, instance, &addr);
if (parent) {
/* Trigger DAG rank recalculation. */
NET_DBG("Neighbor link callback triggering update");
parent->flags |= NET_RPL_PARENT_FLAG_UPDATED;
/* FIXME - Last parameter value (number of
* transmissions) needs adjusting if possible.
*/
net_rpl_of_neighbor_link_cb(iface, parent, status, 1);
parent->last_tx_time = k_uptime_get_32();
}
}
}
#if CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE > 1
static void net_rpl_add_dag(struct net_if *iface,
struct in6_addr *from,
struct net_rpl_dio *dio)
{
struct net_rpl_instance *instance;
struct net_rpl_dag *dag, *previous_dag;
struct net_rpl_parent *parent;
dag = alloc_dag(dio->instance_id, &dio->dag_id);
if (!dag) {
NET_DBG("Failed to allocate a DAG object!");
return;
}
instance = dag->instance;
previous_dag = find_parent_dag(iface, instance, from);
if (!previous_dag) {
parent = net_rpl_add_parent(iface, dag, dio, from);
if (!parent) {
NET_DBG("Adding %s as a parent failed.",
net_sprint_ipv6_addr(from));
net_rpl_dag_set_not_used(dag);
return;
}
NET_DBG("Adding %s as a parent.",
net_sprint_ipv6_addr(from));
} else {
parent = find_parent(iface, previous_dag, from);
if (parent) {
net_rpl_move_parent(iface, previous_dag, dag, parent);
}
}
if (net_rpl_of_find(dio->ocp) ||
instance->mop != dio->mop ||
instance->max_rank_inc != dio->max_rank_inc ||
instance->min_hop_rank_inc != dio->min_hop_rank_inc ||
instance->dio_interval_doublings != dio->dag_interval_doublings ||
instance->dio_interval_min != dio->dag_interval_min ||
instance->dio_redundancy != dio->dag_redundancy ||
instance->default_lifetime != dio->default_lifetime ||
instance->lifetime_unit != dio->lifetime_unit) {
NET_DBG("DIO for DAG instance %u incompatible with "
"previous DIO", dio->instance_id);
net_rpl_remove_parent(iface, parent, NULL);
net_rpl_dag_set_not_used(dag);
return;
}
net_rpl_dag_set_used(dag);
net_rpl_dag_set_grounded_status(dag, dio->grounded);
net_rpl_dag_set_preference(dag, dio->preference);
dag->version = dio->version;
net_ipaddr_copy(&dag->dag_id, &dio->dag_id);
memcpy(&dag->prefix_info, &dio->prefix_info,
sizeof(struct net_rpl_prefix));
net_rpl_set_preferred_parent(iface, dag, parent);
dag->rank = net_rpl_of_calc_rank(parent, 0);
/* So far this is the lowest rank we are aware of. */
dag->min_rank = dag->rank;
NET_DBG("Joined DAG with instance ID %d rank %d DAG ID %s",
dio->instance_id, dag->min_rank,
net_sprint_ipv6_addr(&dag->dag_id));
net_rpl_process_parent_event(iface, instance, parent);
parent->dtsn = dio->dtsn;
}
#endif /* CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE > 1 */
static int should_send_dao(struct net_rpl_instance *instance,
struct net_rpl_dio *dio,
struct net_rpl_parent *parent)
{
/* If MOP is set to no downward routes no DAO should be sent. */
if (instance->mop == NET_RPL_MOP_NO_DOWNWARD_ROUTES) {
return 0;
}
/* Check if the new DTSN is more recent */
return parent == instance->current_dag->preferred_parent &&
(lollipop_greater_than(dio->dtsn, parent->dtsn));
}
static void net_rpl_process_dio(struct net_if *iface,
struct in6_addr *from,
struct net_rpl_dio *dio)
{
struct net_rpl_dag *dag, *previous_dag;
struct net_rpl_instance *instance;
struct net_rpl_parent *parent;
#if defined(CONFIG_NET_RPL_MOP3)
/* If the root is advertising MOP 2 but we support MOP 3 we can still
* join. In that scenario, we suppress DAOs for multicast targets.
*/
if (dio->mop < NET_RPL_MOP_STORING_NO_MULTICAST)
#else
if (dio->mop != NET_RPL_MOP_DEFAULT)
#endif
{
NET_DBG("Ignoring a DIO with an unsupported MOP %d", dio->mop);
return;
}
dag = get_dag(dio->instance_id, &dio->dag_id);
instance = net_rpl_get_instance(dio->instance_id);
if (dag && instance) {
if (lollipop_greater_than(dio->version, dag->version)) {
if (dag->rank == NET_RPL_ROOT_RANK(instance)) {
uint8_t version;
NET_DBG("Root received inconsistent DIO "
"version number %d rank %d",
dio->version, dag->rank);
version = dio->version;
net_rpl_lollipop_increment(&version);
dag->version = version;
net_rpl_reset_dio_timer(instance);
} else {
NET_DBG("Global repair");
if (dio->prefix_info.length != 0 &&
dio->prefix_info.flags &
NET_ICMPV6_RA_FLAG_AUTONOMOUS) {
NET_DBG("Prefix announced in DIO");
net_rpl_set_prefix(iface, dag,
&dio->prefix_info.prefix,
dio->prefix_info.length);
}
global_repair(iface, from, dag, dio);
}
return;
}
if (lollipop_greater_than(dag->version, dio->version)) {
/* The DIO sender is on an older version of the DAG. */
NET_DBG("old version received => inconsistency "
"detected");
if (net_rpl_dag_is_joined(dag)) {
net_rpl_reset_dio_timer(instance);
return;
}
}
}
if (!instance) {
/* Join the RPL DAG if there is no join callback or the join
* callback tells us to join.
*/
if (!rpl_join_callback || rpl_join_callback(dio)) {
NET_DBG("New instance detected: joining...");
net_rpl_join_instance(iface, from, dio);
} else {
NET_DBG("New instance detected: not joining, "
"rejected by join callback");
}
return;
}
if (instance->current_dag->rank == NET_RPL_ROOT_RANK(instance) &&
instance->current_dag != dag) {
NET_DBG("Root ignored DIO for different DAG");
return;
}
if (!dag) {
#if CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE > 1
NET_DBG("Adding new DAG to known instance.");
net_rpl_add_dag(iface, from, dio);
#else
NET_DBG("Only one instance supported.");
#endif /* CONFIG_NET_RPL_MAX_DAG_PER_INSTANCE > 1 */
return;
}
if (dio->rank < NET_RPL_ROOT_RANK(instance)) {
NET_DBG("Ignoring DIO with too low rank %d", dio->rank);
return;
} else if (dio->rank == NET_RPL_INFINITE_RANK &&
net_rpl_dag_is_joined(dag)) {
net_rpl_reset_dio_timer(instance);
}
/* Prefix Information Option treated to add new prefix */
if (dio->prefix_info.length != 0) {
if (dio->prefix_info.flags & NET_ICMPV6_RA_FLAG_AUTONOMOUS) {
NET_DBG("Prefix announced in DIO");
net_rpl_set_prefix(iface, dag, &dio->prefix_info.prefix,
dio->prefix_info.length);
}
}
if (dag->rank == NET_RPL_ROOT_RANK(instance)) {
if (dio->rank != NET_RPL_INFINITE_RANK) {
instance->dio_counter++;
}
return;
}
/*
* At this point, we know that this DIO pertains to a DAG that
* we are already part of. We consider the sender of the DIO to be
* a candidate parent, and let net_rpl_process_parent_event decide
* whether to keep it in the set.
*/
parent = find_parent(iface, dag, from);
if (!parent) {
previous_dag = find_parent_dag(iface, instance, from);
if (!previous_dag) {
/* Add the DIO sender as a candidate parent. */
parent = net_rpl_add_parent(iface, dag, dio, from);
if (!parent) {
NET_DBG("Failed to add a new parent %s",
net_sprint_ipv6_addr(from));
return;
}
NET_DBG("New candidate parent %s with rank %d",
net_sprint_ipv6_addr(from), parent->rank);
} else {
parent = find_parent(iface, previous_dag, from);
if (parent) {
net_rpl_move_parent(iface, previous_dag,
dag, parent);
}
}
} else {
if (parent->rank == dio->rank) {
NET_DBG("Received consistent DIO");
if (net_rpl_dag_is_joined(dag)) {
instance->dio_counter++;
}
} else {
parent->rank = dio->rank;
}
}
/* Parent info has been updated, trigger rank recalculation */
parent->flags |= NET_RPL_PARENT_FLAG_UPDATED;
net_rpl_print_parent_info(parent, instance);
/* We have allocated a candidate parent; process the DIO further. */
#if !defined(CONFIG_NET_RPL_DAG_MC_NONE)
memcpy(&parent->mc, &dio->mc, sizeof(parent->mc));
#endif
if (!net_rpl_process_parent_event(iface, instance, parent)) {
NET_DBG("The candidate parent is rejected.");
return;
}
/* We don't use route control, so we can have only one official
* parent.
*/
if (net_rpl_dag_is_joined(dag) && parent == dag->preferred_parent) {
if (should_send_dao(instance, dio, parent)) {
net_rpl_lollipop_increment(&instance->dtsn);
net_rpl_schedule_dao(instance);
}
/* We received a new DIO from our preferred parent.
* Add default route to set a fresh value for the lifetime
* counter.
*/
net_if_ipv6_router_add(iface, from,
net_rpl_lifetime(instance,
instance->default_lifetime));
}
parent->dtsn = dio->dtsn;
}
static enum net_verdict handle_dio(struct net_buf *buf)
{
struct net_rpl_dio dio = { 0 };
struct net_buf *frag;
struct net_nbr *nbr;
uint16_t offset, pos;
uint8_t subopt_type;
uint8_t flags, len, tmp;
net_rpl_info(buf, "DODAG Information Object");
/* Default values can be overwritten by DIO config option.
*/
dio.dag_interval_doublings = CONFIG_NET_RPL_DIO_INTERVAL_DOUBLINGS;
dio.dag_interval_min = CONFIG_NET_RPL_DIO_INTERVAL_MIN;
dio.dag_redundancy = CONFIG_NET_RPL_DIO_REDUNDANCY;
dio.min_hop_rank_inc = CONFIG_NET_RPL_MIN_HOP_RANK_INC;
dio.max_rank_inc = NET_RPL_MAX_RANK_INC;
dio.ocp = net_rpl_of_get();
dio.default_lifetime = CONFIG_NET_RPL_DEFAULT_LIFETIME;
dio.lifetime_unit = CONFIG_NET_RPL_DEFAULT_LIFETIME_UNIT;
nbr = net_ipv6_nbr_lookup(net_nbuf_iface(buf),
&NET_IPV6_BUF(buf)->src);
if (!nbr) {
NET_ASSERT_INFO(net_nbuf_ll_src(buf)->len,
"Link layer address not set");
nbr = net_ipv6_nbr_add(net_nbuf_iface(buf),
&NET_IPV6_BUF(buf)->src,
net_nbuf_ll_src(buf),
0,
NET_NBR_REACHABLE);
if (!nbr) {
NET_DBG("Cannot add neighbor by DIO");
goto out;
}
net_ipv6_nbr_set_reachable_timer(net_nbuf_iface(buf), nbr);
}
/* offset tells now where the ICMPv6 header is starting */
offset = net_nbuf_icmp_data(buf) - net_nbuf_ip_data(buf);
offset += sizeof(struct net_icmp_hdr);
/* First the DIO option. */
frag = net_nbuf_read_u8(buf->frags, offset, &pos, &dio.instance_id);
frag = net_nbuf_read_u8(frag, pos, &pos, &dio.version);
frag = net_nbuf_read_be16(frag, pos, &pos, &dio.rank);
NET_DBG("Incoming DIO len %d id %d ver %d rank %d",
net_buf_frags_len(buf) - offset,
dio.instance_id, dio.version, dio.rank);
frag = net_nbuf_read_u8(frag, pos, &pos, &flags);
dio.grounded = flags & NET_RPL_DIO_GROUNDED;
dio.mop = (flags & NET_RPL_DIO_MOP_MASK) >> NET_RPL_DIO_MOP_SHIFT;
dio.preference = flags & NET_RPL_DIO_PREFERENCE_MASK;
frag = net_nbuf_read_u8(frag, pos, &pos, &dio.dtsn);
/* two reserved bytes */
frag = net_nbuf_skip(frag, pos, &pos, 2);
frag = net_nbuf_read(frag, pos, &pos, sizeof(dio.dag_id),
dio.dag_id.s6_addr);
NET_DBG("Incoming DIO dag_id %s pref %d",
net_sprint_ipv6_addr(&dio.dag_id), dio.preference);
/* Handle any DIO suboptions */
while (frag) {
frag = net_nbuf_read_u8(frag, pos, &pos, &subopt_type);
if (pos == 0) {
/* We are at the end of the message */
frag = NULL;
break;
}
if (subopt_type == NET_RPL_OPTION_PAD1) {
len = 1;
} else {
/* Suboption with a two-byte header + payload */
frag = net_nbuf_read_u8(frag, pos, &pos, &tmp);
len = 2 + tmp;
}
if (!frag && pos) {
NET_DBG("Invalid DIO packet");
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
NET_DBG("DIO option %u length %d", subopt_type, len - 2);
switch (subopt_type) {
case NET_RPL_OPTION_DAG_METRIC_CONTAINER:
if (len < 6) {
NET_DBG("Invalid DAG MC len %d", len);
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
frag = net_nbuf_read_u8(frag, pos, &pos, &dio.mc.type);
frag = net_nbuf_read_u8(frag, pos, &pos, &tmp);
dio.mc.flags = tmp << 1;
frag = net_nbuf_read_u8(frag, pos, &pos, &tmp);
dio.mc.flags |= tmp >> 7;
dio.mc.aggregated = (tmp >> 4) & 0x3;
dio.mc.precedence = tmp & 0xf;
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.mc.length);
if (dio.mc.type == NET_RPL_MC_ETX) {
frag = net_nbuf_read_be16(frag, pos, &pos,
&dio.mc.obj.etx);
NET_DBG("DAG MC type %d flags %d aggr %d "
"prec %d length %d ETX %d",
dio.mc.type, dio.mc.flags,
dio.mc.aggregated,
dio.mc.precedence, dio.mc.length,
dio.mc.obj.etx);
} else if (dio.mc.type == NET_RPL_MC_ENERGY) {
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.mc.obj.energy.flags);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.mc.obj.energy.estimation);
} else {
NET_DBG("Unhandled DAG MC type %d",
dio.mc.type);
goto out;
}
break;
case NET_RPL_OPTION_ROUTE_INFO:
if (len < 9) {
NET_DBG("Invalid destination prefix "
"option len %d", len);
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.destination_prefix.length);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.destination_prefix.flags);
frag = net_nbuf_read_be32(frag, pos, &pos,
&dio.destination_prefix.lifetime);
if (((dio.destination_prefix.length + 7) / 8) + 8 <=
len && dio.destination_prefix.length <= 128) {
frag = net_nbuf_read(frag, pos, &pos,
(dio.destination_prefix.length + 7) / 8,
dio.destination_prefix.prefix.s6_addr);
NET_DBG("Copying destination prefix %s/%d",
net_sprint_ipv6_addr(
&dio.destination_prefix.prefix),
dio.destination_prefix.length);
} else {
NET_DBG("Invalid route info option len %d",
len);
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
break;
case NET_RPL_OPTION_DAG_CONF:
if (len != 16) {
NET_DBG("Invalid DAG configuration option "
"len %d", len);
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
/* Path control field not yet implemented (1 byte) */
frag = net_nbuf_skip(frag, pos, &pos, 1);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.dag_interval_doublings);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.dag_interval_min);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.dag_redundancy);
frag = net_nbuf_read_be16(frag, pos, &pos,
&dio.max_rank_inc);
frag = net_nbuf_read_be16(frag, pos, &pos,
&dio.min_hop_rank_inc);
frag = net_nbuf_read_be16(frag, pos, &pos,
&dio.ocp);
/* one reserved byte */
frag = net_nbuf_skip(frag, pos, &pos, 1);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.default_lifetime);
frag = net_nbuf_read_be16(frag, pos, &pos,
&dio.lifetime_unit);
NET_DBG("DAG conf dbl %d min %d red %d maxinc %d "
"mininc %d ocp %d d_l %d l_u %d",
dio.dag_interval_doublings,
dio.dag_interval_min,
dio.dag_redundancy, dio.max_rank_inc,
dio.min_hop_rank_inc, dio.ocp,
dio.default_lifetime, dio.lifetime_unit);
break;
case NET_RPL_OPTION_PREFIX_INFO:
if (len != 32) {
NET_DBG("Invalid DAG prefix info len %d != 32",
len);
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.prefix_info.length);
frag = net_nbuf_read_u8(frag, pos, &pos,
&dio.prefix_info.flags);
/* skip valid lifetime atm */
frag = net_nbuf_skip(frag, pos, &pos, 4);
/* preferred lifetime stored in lifetime */
frag = net_nbuf_read_be32(frag, pos, &pos,
&dio.prefix_info.lifetime);
/* 32-bit reserved */
frag = net_nbuf_skip(frag, pos, &pos, 4);
frag = net_nbuf_read(frag, pos, &pos,
sizeof(struct in6_addr),
dio.prefix_info.prefix.s6_addr);
NET_DBG("Prefix %s/%d",
net_sprint_ipv6_addr(&dio.prefix_info.prefix),
dio.prefix_info.length);
break;
default:
NET_DBG("Unsupported suboption type in DIO %d",
subopt_type);
}
}
NET_ASSERT_INFO(!pos && !frag, "DIO reading failure");
net_rpl_process_dio(net_nbuf_iface(buf), &NET_IPV6_BUF(buf)->src,
&dio);
out:
return NET_DROP;
}
int net_rpl_dao_send(struct net_if *iface,
struct net_rpl_parent *parent,
struct in6_addr *prefix,
uint8_t lifetime)
{
uint16_t value = 0;
struct net_rpl_instance *instance;
const struct in6_addr *src;
struct net_rpl_dag *dag;
struct in6_addr *dst;
struct net_buf *buf;
uint8_t prefix_bytes;
uint8_t prefixlen;
int ret;
/* No DAOs in feather mode. */
if (net_rpl_get_mode() == NET_RPL_MODE_FEATHER) {
return -EINVAL;
}
if (!parent || !parent->dag) {
NET_DBG("DAO error parent %p dag %p",
parent, parent ? parent->dag : NULL);
return -EINVAL;
}
dag = parent->dag;
instance = dag->instance;
if (!instance) {
NET_DBG("RPL DAO error no instance");
return -EINVAL;
}
dst = net_rpl_get_parent_addr(iface, parent);
if (!dst) {
NET_DBG("No destination address for parent %p", parent);
return -EINVAL;
}
src = net_if_ipv6_select_src_addr(iface, dst);
if (net_ipv6_addr_cmp(src, net_ipv6_unspecified_address())) {
NET_DBG("Invalid src addr %s found",
net_sprint_ipv6_addr(src));
return -EINVAL;
}
buf = net_nbuf_get_reserve_tx(0);
if (!buf) {
return -ENOMEM;
}
buf = net_ipv6_create_raw(buf, net_if_get_ll_reserve(iface, src),
src, dst, iface, IPPROTO_ICMPV6);
net_nbuf_set_iface(buf, iface);
net_nbuf_set_ll_reserve(buf, net_if_get_ll_reserve(iface, dst));
setup_icmpv6_hdr(buf, NET_ICMPV6_RPL, NET_RPL_DEST_ADV_OBJ);
net_rpl_lollipop_increment(&rpl_dao_sequence);
net_nbuf_append_u8(buf, instance->instance_id);
#if defined(CONFIG_NET_RPL_DAO_SPECIFY_DAG)
value |= NET_RPL_DAO_D_FLAG;
#endif
#if defined(CONFIG_NET_RPL_DAO_ACK)
value |= NET_RPL_DAO_K_FLAG;
#endif
net_nbuf_append_u8(buf, value);
net_nbuf_append_u8(buf, 0); /* reserved */
net_nbuf_append_u8(buf, rpl_dao_sequence);
#if defined(CONFIG_NET_RPL_DAO_SPECIFY_DAG)
net_nbuf_append(buf, sizeof(dag->dag_id), dag->dag_id.s6_addr);
#endif
prefixlen = sizeof(*prefix) * CHAR_BIT;
prefix_bytes = (prefixlen + 7) / CHAR_BIT;
net_nbuf_append_u8(buf, NET_RPL_OPTION_TARGET);
net_nbuf_append_u8(buf, 2 + prefix_bytes);
net_nbuf_append_u8(buf, 0); /* reserved */
net_nbuf_append_u8(buf, prefixlen);
net_nbuf_append(buf, prefix_bytes, prefix->s6_addr);
net_nbuf_append_u8(buf, NET_RPL_OPTION_TRANSIT);
net_nbuf_append_u8(buf, 4); /* length */
net_nbuf_append_u8(buf, 0); /* flags */
net_nbuf_append_u8(buf, 0); /* path control */
net_nbuf_append_u8(buf, 0); /* path seq */
net_nbuf_append_u8(buf, lifetime);
buf = net_ipv6_finalize_raw(buf, IPPROTO_ICMPV6);
ret = net_send_data(buf);
if (ret >= 0) {
net_rpl_dao_info(buf, src, dst, prefix);
NET_STATS_RPL(++net_stats.icmp.sent);
NET_STATS_RPL(++net_stats.rpl.dao.sent);
} else {
net_nbuf_unref(buf);
}
return ret;
}
static int dao_send(struct net_rpl_parent *parent,
uint8_t lifetime,
struct net_if *iface)
{
struct in6_addr *prefix;
prefix = net_if_ipv6_get_global_addr(&iface);
if (!prefix) {
NET_DBG("Will not send DAO as no global address was found.");
return -EDESTADDRREQ;
}
NET_ASSERT_INFO(iface, "Interface not set");
return net_rpl_dao_send(iface, parent, prefix, lifetime);
}
static inline int dao_forward(struct net_if *iface,
struct net_buf *orig,
struct in6_addr *dst)
{
struct net_buf *buf;
int ret;
buf = net_nbuf_get_reserve_tx(0);
if (!buf) {
return -ENOMEM;
}
/* Steal the fragment chain */
buf->frags = orig->frags;
orig->frags = NULL;
net_ipaddr_copy(&NET_IPV6_BUF(buf)->dst, dst);
net_nbuf_set_iface(buf, iface);
net_nbuf_set_ll_reserve(buf, net_if_get_ll_reserve(iface, dst));
ret = net_send_data(buf);
if (ret >= 0) {
NET_STATS_RPL(++net_stats.icmp.sent);
NET_STATS_RPL(++net_stats.rpl.dao.forwarded);
} else {
net_nbuf_unref(buf);
}
return ret;
}
static int dao_ack_send(struct net_buf *orig,
struct net_rpl_instance *instance,
struct in6_addr *dst,
uint8_t sequence)
{
struct in6_addr *src = &NET_IPV6_BUF(orig)->dst;
struct net_if *iface = net_nbuf_iface(orig);
struct net_buf *buf;
int ret;
NET_DBG("Sending a DAO ACK with sequence number %d to %s",
sequence, net_sprint_ipv6_addr(dst));
buf = net_nbuf_get_reserve_tx(0);
if (!buf) {
return -ENOMEM;
}
buf = net_ipv6_create_raw(buf, net_if_get_ll_reserve(iface, src),
src, dst, iface, IPPROTO_ICMPV6);
net_nbuf_set_iface(buf, iface);
net_nbuf_set_ll_reserve(buf, net_if_get_ll_reserve(iface, dst));
setup_icmpv6_hdr(buf, NET_ICMPV6_RPL, NET_RPL_DEST_ADV_OBJ_ACK);
net_nbuf_append_u8(buf, instance->instance_id);
net_nbuf_append_u8(buf, 0); /* reserved */
net_nbuf_append_u8(buf, sequence);
net_nbuf_append_u8(buf, 0); /* status */
buf = net_ipv6_finalize_raw(buf, IPPROTO_ICMPV6);
ret = net_send_data(buf);
if (ret >= 0) {
net_rpl_dao_ack_info(buf, src, dst, instance->instance_id,
sequence);
NET_STATS_RPL(++net_stats.icmp.sent);
NET_STATS_RPL(++net_stats.rpl.dao_ack.sent);
} else {
net_nbuf_unref(buf);
}
return 0;
}
static void forwarding_dao(struct net_rpl_instance *instance,
struct net_rpl_dag *dag,
struct in6_addr *dao_sender,
struct net_buf *buf,
uint8_t sequence,
uint8_t flags,
char *str)
{
struct in6_addr *paddr;
paddr = net_rpl_get_parent_addr(instance->iface,
dag->preferred_parent);
if (paddr) {
NET_DBG("%s %s", str, net_sprint_ipv6_addr(paddr));
dao_forward(dag->instance->iface, buf, paddr);
if (flags & NET_RPL_DAO_K_FLAG) {
dao_ack_send(buf, instance, dao_sender, sequence);
}
}
}
static enum net_verdict handle_dao(struct net_buf *buf)
{
struct in6_addr *dao_sender = &NET_IPV6_BUF(buf)->src;
struct net_rpl_route_entry *extra = NULL;
struct net_rpl_parent *parent = NULL;
enum net_rpl_route_source learned_from;
struct net_rpl_instance *instance;
struct net_route_entry *route;
struct net_rpl_dag *dag;
struct net_buf *frag;
struct in6_addr addr;
struct net_nbr *nbr;
uint16_t offset;
uint16_t pos;
uint8_t sequence;
uint8_t instance_id;
uint8_t lifetime;
uint8_t target_len;
uint8_t flags;
uint8_t subopt_type;
int len;
net_rpl_info(buf, "Destination Advertisement Object");
/* offset tells now where the ICMPv6 header is starting */
offset = net_nbuf_icmp_data(buf) - net_nbuf_ip_data(buf);
offset += sizeof(struct net_icmp_hdr);
frag = net_nbuf_read_u8(buf->frags, offset, &pos, &instance_id);
instance = net_rpl_get_instance(instance_id);
if (!instance) {
NET_DBG("Ignoring DAO for an unknown instance %d",
instance_id);
return NET_DROP;
}
lifetime = instance->default_lifetime;
frag = net_nbuf_read_u8(frag, pos, &pos, &flags);
frag = net_nbuf_skip(frag, pos, &pos, 1); /* reserved */
frag = net_nbuf_read_u8(frag, pos, &pos, &sequence);
dag = instance->current_dag;
/* Is the DAG ID present? */
if (flags & NET_RPL_DAO_D_FLAG) {
frag = net_nbuf_read(frag, pos, &pos, sizeof(addr),
addr.s6_addr);
if (memcmp(&dag->dag_id, &addr, sizeof(dag->dag_id))) {
NET_DBG("Ignoring DAO for a DAG %s different from ours",
net_sprint_ipv6_addr(&dag->dag_id));
return NET_DROP;
}
}
learned_from = net_is_ipv6_addr_mcast(dao_sender) ?
NET_RPL_ROUTE_MULTICAST_DAO :
NET_RPL_ROUTE_UNICAST_DAO;
NET_DBG("DAO from %s", learned_from == NET_RPL_ROUTE_UNICAST_DAO ?
"unicast" : "multicast");
if (learned_from == NET_RPL_ROUTE_UNICAST_DAO) {
/* Check whether this is a DAO forwarding loop. */
parent = find_parent(instance->iface, dag, dao_sender);
/* Check if this is a new DAO registration with an "illegal"
* rank if we already route to this node it is likely.
*/
if (parent &&
NET_RPL_DAG_RANK(parent->rank, instance) <
NET_RPL_DAG_RANK(dag->rank, instance)) {
NET_DBG("Loop detected when receiving a unicast DAO "
"from a node with a lower rank! (%d < %d)",
NET_RPL_DAG_RANK(parent->rank, instance),
NET_RPL_DAG_RANK(dag->rank, instance));
parent->rank = NET_RPL_INFINITE_RANK;
parent->flags |= NET_RPL_PARENT_FLAG_UPDATED;
return NET_DROP;
}
/* If we get the DAO from our parent, we also have a loop. */
if (parent && parent == dag->preferred_parent) {
NET_DBG("Loop detected when receiving a unicast DAO "
"from our parent");
parent->rank = NET_RPL_INFINITE_RANK;
parent->flags |= NET_RPL_PARENT_FLAG_UPDATED;
return NET_DROP;
}
}
target_len = 0;
/* Handle any DAO suboptions */
while (frag) {
frag = net_nbuf_read_u8(frag, pos, &pos, &subopt_type);
if (pos == 0) {
/* We are at the end of the message */
frag = NULL;
break;
}
if (subopt_type == NET_RPL_OPTION_PAD1) {
len = 1;
} else {
uint8_t tmp;
/* Suboption with a two-byte header + payload */
frag = net_nbuf_read_u8(frag, pos, &pos, &tmp);
len = 2 + tmp;
}
if (!frag && pos) {
NET_DBG("Invalid DAO packet");
NET_STATS_RPL(net_stats.rpl.malformed_msgs++);
goto out;
}
NET_DBG("DAO option %u length %d", subopt_type, len - 2);
switch (subopt_type) {
case NET_RPL_OPTION_TARGET:
frag = net_nbuf_skip(frag, pos, &pos, 1); /* reserved */
frag = net_nbuf_read_u8(frag, pos, &pos, &target_len);
frag = net_nbuf_read(frag, pos, &pos,
(target_len + 7) / 8,
addr.s6_addr);
break;
case NET_RPL_OPTION_TRANSIT:
/* The path sequence and control are ignored. */
frag = net_nbuf_skip(frag, pos, &pos, 2);
frag = net_nbuf_read_u8(frag, pos, &pos, &lifetime);
break;
}
}
NET_DBG("DAO lifetime %d addr %s/%d", lifetime,
net_sprint_ipv6_addr(&addr), target_len);
#if NET_RPL_MULTICAST
if (net_is_ipv6_addr_mcast_global(&addr)) {
struct net_route_entry_mcast *mcast_group;
mcast_group = net_route_mcast_add(net_nbuf_iface(buf), &addr);
if (mcast_group) {
mcast_group->data = (void *)dag;
mcast_group->lifetime = net_rpl_lifetime(instance,
lifetime);
}
goto fwd_dao;
}
#endif
route = net_route_lookup(net_nbuf_iface(buf), &addr);
if (lifetime == NET_RPL_ZERO_LIFETIME) {
struct in6_addr *nexthop;
NET_DBG("No-Path DAO received");
nbr = net_route_get_nbr(route);
extra = net_nbr_extra_data(nbr);
nexthop = net_route_get_nexthop(route);
/* No-Path DAO received; invoke the route purging routine. */
if (route && !extra->no_path_received &&
route->prefix_len == target_len && nexthop &&
net_ipv6_addr_cmp(nexthop, dao_sender)) {
NET_DBG("Setting expiration timer for target %s",
net_sprint_ipv6_addr(&addr));
extra->no_path_received = true;
extra->lifetime = NET_RPL_DAO_EXPIRATION_TIMEOUT;
/* We forward the incoming no-path DAO to our parent,
* if we have one.
*/
if (dag->preferred_parent) {
forwarding_dao(instance, dag, dao_sender,
buf, sequence, flags,
#if NET_DEBUG
"Forwarding no-path DAO to "
"parent"
#else
""
#endif
);
}
}
return NET_DROP;
}
NET_DBG("Adding DAO route");
nbr = net_ipv6_nbr_lookup(net_nbuf_iface(buf), dao_sender);
if (!nbr) {
nbr = net_ipv6_nbr_add(net_nbuf_iface(buf), dao_sender,
net_nbuf_ll_src(buf), false,
NET_NBR_REACHABLE);
if (nbr) {
/* Set reachable timer */
net_ipv6_nbr_set_reachable_timer(net_nbuf_iface(buf),
nbr);
NET_DBG("Neighbor %s [%s] added to neighbor cache",
net_sprint_ipv6_addr(dao_sender),
net_sprint_ll_addr(net_nbuf_ll_src(buf)->addr,
net_nbuf_ll_src(buf)->len));
} else {
NET_DBG("Out of memory, dropping DAO from %s [%s]",
net_sprint_ipv6_addr(dao_sender),
net_sprint_ll_addr(net_nbuf_ll_src(buf)->addr,
net_nbuf_ll_src(buf)->len));
return NET_DROP;
}
} else {
NET_DBG("Neighbor %s [%s] already in neighbor cache",
net_sprint_ipv6_addr(dao_sender),
net_sprint_ll_addr(net_nbuf_ll_src(buf)->addr,
net_nbuf_ll_src(buf)->len));
}
route = net_rpl_add_route(dag, net_nbuf_iface(buf),
&addr, target_len, dao_sender);
if (!route) {
NET_STATS_RPL(net_stats.rpl.mem_overflows++);
NET_DBG("Could not add a route after receiving a DAO");
return NET_DROP;
}
if (extra) {
extra->lifetime = net_rpl_lifetime(instance, lifetime);
extra->route_source = learned_from;
extra->no_path_received = false;
}
#if NET_RPL_MULTICAST
fwd_dao:
#endif
if (learned_from == NET_RPL_ROUTE_UNICAST_DAO) {
if (dag->preferred_parent) {
forwarding_dao(instance, dag,
dao_sender, buf,
sequence, flags,
#if NET_DEBUG
"Forwarding DAO to parent"
#else
""
#endif
);
}
}
out:
return NET_DROP;
}
static enum net_verdict handle_dao_ack(struct net_buf *buf)
{
net_rpl_info(buf, "Destination Advertisement Object Ack");
NET_STATS_RPL(++net_stats.rpl.dao_ack.recv);
return NET_DROP;
}
static struct net_icmpv6_handler dodag_info_solicitation_handler = {
.type = NET_ICMPV6_RPL,
.code = NET_RPL_DODAG_SOLICIT,
.handler = handle_dis,
};
static struct net_icmpv6_handler dodag_information_object_handler = {
.type = NET_ICMPV6_RPL,
.code = NET_RPL_DODAG_INFO_OBJ,
.handler = handle_dio,
};
static struct net_icmpv6_handler destination_advertisement_object_handler = {
.type = NET_ICMPV6_RPL,
.code = NET_RPL_DEST_ADV_OBJ,
.handler = handle_dao,
};
static struct net_icmpv6_handler dao_ack_handler = {
.type = NET_ICMPV6_RPL,
.code = NET_RPL_DEST_ADV_OBJ_ACK,
.handler = handle_dao_ack,
};
int net_rpl_update_header(struct net_buf *buf, struct in6_addr *addr)
{
uint16_t pos = 0;
struct net_rpl_parent *parent;
struct net_buf *frag;
uint8_t next;
uint8_t len;
frag = buf->frags;
if (NET_IPV6_BUF(buf)->nexthdr == NET_IPV6_NEXTHDR_HBHO) {
/* The HBHO will start right after IPv6 header */
frag = net_nbuf_skip(frag, pos, &pos,
sizeof(struct net_ipv6_hdr));
if (!frag && pos) {
/* Not enough data in the message */
return -EMSGSIZE;
}
frag = net_nbuf_read(frag, pos, &pos, 1, &next);
frag = net_nbuf_read(frag, pos, &pos, 1, &len);
if (!frag && pos) {
return -EMSGSIZE;
}
if (len != NET_RPL_HOP_BY_HOP_LEN - 8) {
NET_DBG("Non RPL Hop-by-hop options support not "
"implemented");
return 0;
}
if (next == NET_RPL_EXT_HDR_OPT_RPL) {
uint16_t sender_rank, offset;
frag = net_nbuf_skip(frag, pos, &pos, 1); /* opt type */
frag = net_nbuf_skip(frag, pos, &pos, 1); /* opt len */
offset = pos; /* Where the flags is located in the
* packet, that info is need few lines
* below.
*/
frag = net_nbuf_skip(frag, pos, &pos, 1); /* flags */
frag = net_nbuf_skip(frag, pos, &pos, 1); /* instance */
frag = net_nbuf_read(frag, pos, &pos, 2,
(uint8_t *)&sender_rank);
if (!frag && pos) {
return -EMSGSIZE;
}
if (sender_rank == 0) {
NET_DBG("Updating RPL option");
if (!rpl_default_instance ||
!rpl_default_instance->is_used ||
!net_rpl_dag_is_joined(
rpl_default_instance->current_dag)) {
NET_DBG("Unable to add hop-by-hop "
"extension header: incorrect "
"default instance");
return -EINVAL;
}
parent = find_parent(net_nbuf_iface(buf),
rpl_default_instance->
current_dag,
addr);
if (!parent ||
parent != parent->dag->preferred_parent) {
net_nbuf_write_u8(buf, buf->frags,
offset, &pos,
NET_RPL_HDR_OPT_DOWN);
}
offset++;
net_nbuf_write_u8(buf, buf->frags, offset, &pos,
rpl_default_instance->instance_id);
net_nbuf_write_be16(buf, buf->frags, pos, &pos,
htons(rpl_default_instance->
current_dag->rank));
}
}
}
return 0;
}
bool net_rpl_verify_header(struct net_buf *buf,
uint16_t offset, uint16_t *pos)
{
struct net_rpl_instance *instance;
struct net_buf *frag;
uint16_t sender_rank;
uint8_t instance_id, flags;
bool down, sender_closer;
frag = net_nbuf_read_u8(buf, offset, pos, &flags);
frag = net_nbuf_read_u8(frag, *pos, pos, &instance_id);
frag = net_nbuf_read_be16(frag, *pos, pos, &sender_rank);
if (!frag && *pos == 0xffff) {
return false;
}
instance = net_rpl_get_instance(instance_id);
if (!instance) {
NET_DBG("Unknown instance %u", instance_id);
return false;
}
if (flags & NET_RPL_HDR_OPT_FWD_ERR) {
struct net_route_entry *route;
/* We should try to repair it by removing the neighbor that
* caused the packet to be forwareded in the first place.
* We drop any routes that go through the neighbor that sent
* the packet to us.
*/
NET_DBG("Forward error!");
route = net_route_lookup(net_nbuf_iface(buf),
&NET_IPV6_BUF(buf)->dst);
if (route) {
net_route_del(route);
}
NET_STATS_RPL(net_stats.rpl.forward_errors++);
/* Trigger DAO retransmission */
net_rpl_reset_dio_timer(instance);
/* drop the packet as it is not routable */
return false;
}
if (!net_rpl_dag_is_joined(instance->current_dag)) {
NET_DBG("No DAG in the instance");
return false;
}
if (flags & NET_RPL_HDR_OPT_DOWN) {
down = true;
} else {
down = false;
}
sender_rank = ntohs(sender_rank);
sender_closer = sender_rank < instance->current_dag->rank;
NET_DBG("Packet going %s, sender closer %d (%d < %d)",
down ? "down" : "up", sender_closer, sender_rank,
instance->current_dag->rank);
if ((down && !sender_closer) || (!down && sender_closer)) {
NET_DBG("Loop detected - sender rank %d my-rank %d "
"sender_closer %d",
sender_rank, instance->current_dag->rank,
sender_closer);
if (flags & NET_RPL_HDR_OPT_RANK_ERR) {
NET_STATS_RPL(net_stats.rpl.loop_errors++);
NET_DBG("Rank error signalled in RPL option!");
/* Packet must be dropped and dio trickle timer reset,
* see RFC 6550 - 11.2.2.2
*/
net_rpl_reset_dio_timer(instance);
return false;
}
NET_DBG("Single error tolerated.");
NET_STATS_RPL(net_stats.rpl.loop_warnings++);
net_nbuf_write_u8(buf, buf->frags, offset, pos,
flags | NET_RPL_HDR_OPT_RANK_ERR);
return true;
}
NET_DBG("Rank OK");
return true;
}
static inline int add_rpl_opt(struct net_buf *buf, uint16_t offset)
{
int ext_len = net_nbuf_ext_len(buf);
bool ret;
/* next header */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++,
NET_IPV6_BUF(buf)->nexthdr);
if (!ret) {
return -EINVAL;
}
/* Option len */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++,
NET_RPL_HOP_BY_HOP_LEN - 8);
if (!ret) {
return -EINVAL;
}
/* Sub-option type */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++,
NET_IPV6_EXT_HDR_OPT_RPL);
if (!ret) {
return -EINVAL;
}
/* Sub-option length */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++,
NET_RPL_HDR_OPT_LEN);
if (!ret) {
return -EINVAL;
}
/* RPL option flags */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++, 0);
if (!ret) {
return -EINVAL;
}
/* RPL Instance id */
ret = net_nbuf_insert_u8(buf, buf->frags, offset++, 0);
if (!ret) {
return -EINVAL;
}
/* RPL sender rank */
ret = net_nbuf_insert_be16(buf, buf->frags, offset++, 0);
if (!ret) {
return -EINVAL;
}
NET_IPV6_BUF(buf)->nexthdr = NET_IPV6_NEXTHDR_HBHO;
net_nbuf_set_ext_len(buf, ext_len + NET_RPL_HOP_BY_HOP_LEN);
return 0;
}
static int net_rpl_update_header_empty(struct net_buf *buf)
{
uint16_t offset = sizeof(struct net_ipv6_hdr);
uint8_t next = NET_IPV6_BUF(buf)->nexthdr;
struct net_buf *frag = buf->frags;
struct net_rpl_instance *instance;
struct net_rpl_parent *parent;
struct net_route_entry *route;
uint8_t next_hdr, len, length;
uint8_t opt_type = 0, opt_len;
uint8_t instance_id, flags;
uint16_t pos;
NET_DBG("Verifying the presence of the RPL header option");
frag = net_nbuf_read_u8(frag, offset, &offset, &next_hdr);
frag = net_nbuf_read_u8(frag, offset, &offset, &len);
if (!frag) {
return 0;
}
length = 0;
if (next != NET_IPV6_NEXTHDR_HBHO) {
NET_DBG("No hop-by-hop option found, creating it");
/* We already read 2 bytes so go back accordingly. */
if (add_rpl_opt(buf, offset - 2) < 0) {
NET_DBG("Cannot add RPL options");
return -EINVAL;
}
return 0;
}
if (len != NET_RPL_HOP_BY_HOP_LEN - 8) {
NET_DBG("Hop-by-hop ext header is wrong size "
"(%d vs %d)", length,
NET_RPL_HOP_BY_HOP_LEN - 8);
return 0;
}
length += 2;
/* Each extension option has type and length */
frag = net_nbuf_read_u8(frag, offset, &offset, &opt_type);
frag = net_nbuf_read_u8(frag, offset, &offset, &opt_len);
if (opt_type != NET_IPV6_EXT_HDR_OPT_RPL) {
/* FIXME: go through all the options instead */
NET_DBG("Non RPL Hop-by-hop option check not "
"implemented");
return 0;
}
if (opt_len != NET_RPL_HDR_OPT_LEN) {
NET_DBG("RPL Hop-by-hop option has wrong length");
return 0;
}
frag = net_nbuf_read_u8(buf, offset, &offset, &flags);
frag = net_nbuf_read_u8(frag, offset, &offset, &instance_id);
instance = net_rpl_get_instance(instance_id);
if (!instance || !instance->is_used ||
!instance->current_dag->is_joined) {
NET_DBG("Incorrect instance so hop-by-hop ext header "
"not added");
return 0;
}
if (opt_type != NET_IPV6_EXT_HDR_OPT_RPL) {
NET_DBG("Multi Hop-by-hop options not implemented");
return 0;
}
NET_DBG("Updating RPL option");
/* The offset should point to "rank" right now */
net_nbuf_write_be16(buf, frag, offset, &pos,
instance->current_dag->rank);
offset -= 2; /* move back to flags */
route = net_route_lookup(net_nbuf_iface(buf), &NET_IPV6_BUF(buf)->dst);
/*
* Check the direction of the down flag, as per
* Section 11.2.2.3, which states that if a packet is going
* down it should in general not go back up again. If this
* happens, a NET_RPL_HDR_OPT_FWD_ERR should be flagged.
*/
if (flags & NET_RPL_HDR_OPT_DOWN) {
struct net_nbr *nbr;
if (!route) {
net_nbuf_write_u8(buf, frag, offset, &pos,
flags |= NET_RPL_HDR_OPT_FWD_ERR);
NET_DBG("RPL forwarding error");
/*
* We should send back the packet to the
* originating parent, but it is not feasible
* yet, so we send a No-Path DAO instead.
*/
NET_DBG("RPL generate No-Path DAO");
nbr = net_nbr_lookup(&net_rpl_parents.table,
net_nbuf_iface(buf),
net_nbuf_ll_src(buf));
parent = nbr_data(nbr);
if (parent) {
net_rpl_dao_send(net_nbuf_iface(buf),
parent,
&NET_IPV6_BUF(buf)->dst,
NET_RPL_ZERO_LIFETIME);
}
/* Drop packet */
return -EINVAL;
}
return 0;
}
/*
* Set the down extension flag correctly as described
* in Section 11.2 of RFC6550. If the packet progresses
* along a DAO route, the down flag should be set.
*/
if (!route) {
/* No route was found, so this packet will go
* towards the RPL root. If so, we should not
* set the down flag.
*/
net_nbuf_write_u8(buf, frag, offset, &pos,
flags &= ~NET_RPL_HDR_OPT_DOWN);
NET_DBG("RPL option going up");
} else {
/* A DAO route was found so we set the down
* flag.
*/
net_nbuf_write_u8(buf, frag, offset, &pos,
flags |= NET_RPL_HDR_OPT_DOWN);
NET_DBG("RPL option going down");
}
return 0;
}
int net_rpl_insert_header(struct net_buf *buf)
{
#if defined(CONFIG_NET_RPL_INSERT_HBH_OPTION)
if (rpl_default_instance &&
!net_is_ipv6_addr_mcast(&NET_IPV6_BUF(buf)->dst)) {
return net_rpl_update_header_empty(buf);
}
#endif
return 0;
}
static inline void create_linklocal_rplnodes_mcast(struct in6_addr *addr)
{
net_ipv6_addr_create(addr, 0xff02, 0, 0, 0, 0, 0, 0, 0x001a);
}
#if defined(CONFIG_NET_RPL_DIS_SEND)
static void dis_timeout(struct k_work *work)
{
uint32_t dis_interval;
NET_DBG("DIS Timer triggered at %u", k_uptime_get_32());
net_rpl_dis_send(NULL, NULL);
dis_interval = CONFIG_NET_RPL_DIS_INTERVAL * MSEC_PER_SEC;
k_delayed_work_submit(&dis_timer, dis_interval);
}
#endif
static inline void net_rpl_init_timers(void)
{
#if defined(CONFIG_NET_RPL_DIS_SEND)
/* Randomize the first DIS sending*/
uint32_t dis_interval;
dis_interval = (CONFIG_NET_RPL_DIS_INTERVAL / 2 +
((uint32_t)CONFIG_NET_RPL_DIS_INTERVAL *
(uint32_t)sys_rand32_get()) / UINT_MAX -
NET_RPL_DIS_START_DELAY) * MSEC_PER_SEC;
k_delayed_work_init(&dis_timer, dis_timeout);
k_delayed_work_submit(&dis_timer, dis_interval);
#endif
}
void net_rpl_init(void)
{
/* Note that link_cb needs to be static as it is added
* to linked list of callbacks.
*/
static struct net_if_link_cb link_cb;
struct in6_addr addr;
NET_DBG("Allocated %d routing entries (%d bytes)",
CONFIG_NET_IPV6_MAX_NEIGHBORS,
sizeof(net_rpl_neighbor_pool));
#if defined(CONFIG_NET_RPL_STATS)
memset(&net_stats.rpl, 0, sizeof(net_stats.rpl));
#endif
rpl_dao_sequence = net_rpl_lollipop_init();
net_rpl_init_timers();
create_linklocal_rplnodes_mcast(&addr);
if (!net_if_ipv6_maddr_add(net_if_get_default(), &addr)) {
NET_ERR("Cannot create RPL multicast address");
/* Ignore error at this point */
}
net_rpl_of_reset(NULL);
net_if_register_link_cb(&link_cb, net_rpl_link_neighbor_callback);
net_icmpv6_register_handler(&dodag_info_solicitation_handler);
net_icmpv6_register_handler(&dodag_information_object_handler);
net_icmpv6_register_handler(&destination_advertisement_object_handler);
net_icmpv6_register_handler(&dao_ack_handler);
}