/**
* \addtogroup uip6
* @{
*/
/*
* Copyright (c) 2010, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* ICMP6 I/O for RPL control messages.
*
* \author Joakim Eriksson <joakime@sics.se>, Nicolas Tsiftes <nvt@sics.se>
* Contributors: Niclas Finne <nfi@sics.se>, Joel Hoglund <joel@sics.se>,
* Mathieu Pouillot <m.pouillot@watteco.com>
*/
#include "net/tcpip.h"
#include "net/uip.h"
#include "net/uip-ds6.h"
#include "net/uip-nd6.h"
#include "net/uip-icmp6.h"
#include "net/rpl/rpl-private.h"
#include "net/packetbuf.h"
#include <limits.h>
#include <string.h>
#define DEBUG DEBUG_NONE
#include "net/uip-debug.h"
/*---------------------------------------------------------------------------*/
#define RPL_DIO_GROUNDED 0x80
#define RPL_DIO_MOP_SHIFT 3
#define RPL_DIO_MOP_MASK 0x3c
#define RPL_DIO_PREFERENCE_MASK 0x07
#define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])
#define UIP_ICMP_BUF ((struct uip_icmp_hdr *)&uip_buf[uip_l2_l3_hdr_len])
#define UIP_ICMP_PAYLOAD ((unsigned char *)&uip_buf[uip_l2_l3_icmp_hdr_len])
/*---------------------------------------------------------------------------*/
static void dis_input(void);
static void dio_input(void);
static void dao_input(void);
static void dao_ack_input(void);
static uint8_t dao_sequence;
/*---------------------------------------------------------------------------*/
static int
get_global_addr(uip_ipaddr_t *addr)
{
int i;
int state;
for(i = 0; i < UIP_DS6_ADDR_NB; i++) {
state = uip_ds6_if.addr_list[i].state;
if(uip_ds6_if.addr_list[i].isused &&
(state == ADDR_TENTATIVE || state == ADDR_PREFERRED)) {
if(!uip_is_addr_link_local(&uip_ds6_if.addr_list[i].ipaddr)) {
memcpy(addr, &uip_ds6_if.addr_list[i].ipaddr, sizeof(uip_ipaddr_t));
return 1;
}
}
}
return 0;
}
/*---------------------------------------------------------------------------*/
static uint32_t
get32(uint8_t *buffer, int pos)
{
return (uint32_t)buffer[pos] << 24 | (uint32_t)buffer[pos + 1] << 16 |
(uint32_t)buffer[pos + 2] << 8 | buffer[pos + 3];
}
/*---------------------------------------------------------------------------*/
static void
set32(uint8_t *buffer, int pos, uint32_t value)
{
buffer[pos++] = value >> 24;
buffer[pos++] = (value >> 16) & 0xff;
buffer[pos++] = (value >> 8) & 0xff;
buffer[pos++] = value & 0xff;
}
/*---------------------------------------------------------------------------*/
static void
dis_input(void)
{
rpl_dag_t *dag;
/* DAG Information Solicitation */
PRINTF("RPL: Received a DIS from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("\n");
dag = rpl_get_dag(RPL_ANY_INSTANCE);
if(dag != NULL) {
if(uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
PRINTF("RPL: Multicast DIS => reset DIO timer\n");
rpl_reset_dio_timer(dag, 0);
} else {
PRINTF("RPL: Unicast DIS, reply to sender\n");
dio_output(dag, &UIP_IP_BUF->srcipaddr);
}
}
}
/*---------------------------------------------------------------------------*/
void
dis_output(uip_ipaddr_t *addr)
{
unsigned char *buffer;
uip_ipaddr_t tmpaddr;
/* DAG Information Solicitation - 2 bytes reserved */
/* 0 1 2 */
/* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 */
/* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
/* | Flags | Reserved | Option(s)... */
/* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
buffer = UIP_ICMP_PAYLOAD;
buffer[0] = buffer[1] = 0;
if(addr == NULL) {
PRINTF("RPL: Sending a DIS\n");
uip_create_linklocal_rplnodes_mcast(&tmpaddr);
addr = &tmpaddr;
} else {
PRINTF("RPL: Sending a unicast DIS\n");
}
uip_icmp6_send(addr, ICMP6_RPL, RPL_CODE_DIS, 2);
}
/*---------------------------------------------------------------------------*/
static void
dio_input(void)
{
unsigned char *buffer;
uint8_t buffer_length;
rpl_dio_t dio;
uint8_t subopt_type;
int i;
int len;
uip_ipaddr_t from;
uip_ds6_nbr_t *nbr;
dio.dag_intdoubl = DEFAULT_DIO_INTERVAL_DOUBLINGS;
dio.dag_intmin = DEFAULT_DIO_INTERVAL_MIN;
dio.dag_redund = DEFAULT_DIO_REDUNDANCY;
uip_ipaddr_copy(&from, &UIP_IP_BUF->srcipaddr);
/* DAG Information Object */
PRINTF("RPL: Received a DIO from ");
PRINT6ADDR(&from);
PRINTF("\n");
if((nbr = uip_ds6_nbr_lookup(&from)) == NULL) {
if((nbr = uip_ds6_nbr_add(&from, (uip_lladdr_t *)
packetbuf_addr(PACKETBUF_ADDR_SENDER),
0, NBR_REACHABLE)) != NULL) {
/* set reachable timer */
stimer_set(&nbr->reachable, UIP_ND6_REACHABLE_TIME / 1000);
PRINTF("RPL: Neighbor added to neighbor cache ");
PRINT6ADDR(&from);
PRINTF(", ");
PRINTLLADDR((uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER));
PRINTF("\n");
}
} else {
PRINTF("RPL: Neighbor already in neighbor cache\n");
}
buffer_length = uip_len - uip_l2_l3_icmp_hdr_len;
#if RPL_CONF_ADJUST_LLH_LEN
buffer_length+=UIP_LLH_LEN; //Add jackdaw, minimal-net ethernet header
#endif
/* Process the DIO base option. */
i = 0;
buffer = UIP_ICMP_PAYLOAD;
dio.instance_id = buffer[i++];
dio.version = buffer[i++];
dio.rank = (buffer[i] << 8) | buffer[i + 1];
i += 2;
PRINTF("RPL: Incoming DIO rank %u\n", (unsigned)dio.rank);
dio.grounded = buffer[i] & RPL_DIO_GROUNDED;
dio.mop = (buffer[i]& RPL_DIO_MOP_MASK) >> RPL_DIO_MOP_SHIFT;
dio.preference = buffer[i++] & RPL_DIO_PREFERENCE_MASK;
dio.dtsn = buffer[i++];
/* two reserved bytes */
i += 2;
memcpy(&dio.dag_id, buffer + i, sizeof(dio.dag_id));
i += sizeof(dio.dag_id);
/* Check if there are any DIO suboptions. */
for(; i < buffer_length; i += len) {
subopt_type = buffer[i];
if(subopt_type == RPL_DIO_SUBOPT_PAD1) {
len = 1;
} else {
/* Suboption with a two-byte header + payload */
len = 2 + buffer[i + 1];
}
if(len + i > buffer_length) {
PRINTF("RPL: Invalid DIO packet\n");
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
PRINTF("RPL: DIO suboption %u, length: %u\n", subopt_type, len - 2);
switch(subopt_type) {
case RPL_DIO_SUBOPT_DAG_METRIC_CONTAINER:
if(len < 6) {
PRINTF("RPL: Invalid DAG MC, len = %d\n", len);
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
dio.mc.type = buffer[i + 2];
dio.mc.flags = buffer[i + 3] << 1;
dio.mc.flags |= buffer[i + 4] >> 7;
dio.mc.aggr = (buffer[i + 4] >> 4) & 0x3;
dio.mc.prec = buffer[i + 4] & 0xf;
dio.mc.length = buffer[i + 5];
if(dio.mc.type == RPL_DAG_MC_ETX) {
dio.mc.obj.etx = buffer[i + 6] << 8;
dio.mc.obj.etx |= buffer[i + 7];
PRINTF("RPL: DAG MC: type %u, flags %u, aggr %u, prec %u, length %u, ETX %u\n",
(unsigned)dio.mc.type,
(unsigned)dio.mc.flags,
(unsigned)dio.mc.aggr,
(unsigned)dio.mc.prec,
(unsigned)dio.mc.length,
(unsigned)dio.mc.obj.etx);
} else if(dio.mc.type == RPL_DAG_MC_ENERGY) {
dio.mc.obj.energy.flags = buffer[i + 6];
dio.mc.obj.energy.energy_est = buffer[i + 7];
} else {
PRINTF("RPL: Unhandled DAG MC type: %u\n", (unsigned)dio.mc.type);
return;
}
break;
case RPL_DIO_SUBOPT_ROUTE_INFO:
if(len < 9) {
PRINTF("RPL: Invalid destination prefix option, len = %d\n", len);
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
/* flags is both preference and flags for now */
dio.destination_prefix.length = buffer[i + 2];
dio.destination_prefix.flags = buffer[i + 3];
dio.destination_prefix.lifetime = get32(buffer, i + 4);
if(((dio.destination_prefix.length + 7)/ 8) + 8 <= len &&
dio.destination_prefix.length <= 128) {
PRINTF("RPL: Copying destination prefix\n");
memcpy(&dio.destination_prefix.prefix, &buffer[i + 8],
(dio.destination_prefix.length + 7) / 8);
} else {
PRINTF("RPL: Invalid route infoprefix option, len = %d\n", len);
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
break;
case RPL_DIO_SUBOPT_DAG_CONF:
if(len != 16) {
PRINTF("RPL: Invalid DAG configuration option, len = %d\n", len);
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
/* Path control field not yet implemented - at i + 2 */
dio.dag_intdoubl = buffer[i + 3];
dio.dag_intmin = buffer[i + 4];
dio.dag_redund = buffer[i + 5];
dio.dag_max_rankinc = (buffer[i + 6] << 8) | buffer[i + 7];
dio.dag_min_hoprankinc = (buffer[i + 8] << 8) | buffer[i + 9];
dio.ocp = (buffer[i + 10] << 8) | buffer[i + 11];
/* buffer + 12 is reserved */
dio.default_lifetime = buffer[i + 13];
dio.lifetime_unit = (buffer[i + 14] << 8) | buffer[i + 15];
PRINTF("RPL: DIO Conf:dbl=%d, min=%d red=%d maxinc=%d mininc=%d ocp=%d d_l=%u l_u=%u\n",
dio.dag_intdoubl, dio.dag_intmin, dio.dag_redund,
dio.dag_max_rankinc, dio.dag_min_hoprankinc, dio.ocp,
dio.default_lifetime, dio.lifetime_unit);
break;
case RPL_DIO_SUBOPT_PREFIX_INFO:
if(len != 32) {
PRINTF("RPL: DAG Prefix info not ok, len != 32\n");
RPL_STAT(rpl_stats.malformed_msgs++);
return;
}
dio.prefix_info.length = buffer[i + 2];
dio.prefix_info.flags = buffer[i + 3];
/* valid lifetime is ingnored for now - at i + 4 */
/* preferred lifetime stored in lifetime */
dio.prefix_info.lifetime = get32(buffer, i + 8);
/* 32-bit reserved at i + 12 */
PRINTF("RPL: Copying prefix information\n");
memcpy(&dio.prefix_info.prefix, &buffer[i + 16], 16);
break;
default:
PRINTF("RPL: Unsupported suboption type in DIO: %u\n",
(unsigned)subopt_type);
}
}
rpl_process_dio(&from, &dio);
}
/*---------------------------------------------------------------------------*/
void
dio_output(rpl_dag_t *dag, uip_ipaddr_t *uc_addr)
{
unsigned char *buffer;
int pos;
uip_ipaddr_t addr;
/* DAG Information Object */
pos = 0;
buffer = UIP_ICMP_PAYLOAD;
buffer[pos++] = dag->instance_id;
buffer[pos++] = dag->version;
buffer[pos++] = dag->rank >> 8;
buffer[pos++] = dag->rank & 0xff;
buffer[pos] = 0;
if(dag->grounded) {
buffer[pos] |= RPL_DIO_GROUNDED;
}
buffer[pos] = dag->mop << RPL_DIO_MOP_SHIFT;
pos++;
buffer[pos++] = ++dag->dtsn_out;
/* reserved 2 bytes */
buffer[pos++] = 0; /* flags */
buffer[pos++] = 0; /* reserved */
memcpy(buffer + pos, &dag->dag_id, sizeof(dag->dag_id));
pos += 16;
if(dag->mc.type != RPL_DAG_MC_NONE) {
dag->of->update_metric_container(dag);
buffer[pos++] = RPL_DIO_SUBOPT_DAG_METRIC_CONTAINER;
buffer[pos++] = 6;
buffer[pos++] = dag->mc.type;
buffer[pos++] = dag->mc.flags >> 1;
buffer[pos] = (dag->mc.flags & 1) << 7;
buffer[pos++] |= (dag->mc.aggr << 4) | dag->mc.prec;
if(dag->mc.type == RPL_DAG_MC_ETX) {
buffer[pos++] = 2;
buffer[pos++] = dag->mc.obj.etx >> 8;
buffer[pos++] = dag->mc.obj.etx & 0xff;
} else if(dag->mc.type == RPL_DAG_MC_ENERGY) {
buffer[pos++] = 2;
buffer[pos++] = dag->mc.obj.energy.flags;
buffer[pos++] = dag->mc.obj.energy.energy_est;
} else {
PRINTF("RPL: Unable to send DIO because of unhandled DAG MC type %u\n",
(unsigned)dag->mc.type);
return;
}
}
/* Always add a sub-option for DAG configuration. */
buffer[pos++] = RPL_DIO_SUBOPT_DAG_CONF;
buffer[pos++] = 14;
buffer[pos++] = 0; /* No Auth, PCS = 0 */
buffer[pos++] = dag->dio_intdoubl;
buffer[pos++] = dag->dio_intmin;
buffer[pos++] = dag->dio_redundancy;
buffer[pos++] = dag->max_rankinc >> 8;
buffer[pos++] = dag->max_rankinc & 0xff;
buffer[pos++] = dag->min_hoprankinc >> 8;
buffer[pos++] = dag->min_hoprankinc & 0xff;
/* OCP is in the DAG_CONF option */
buffer[pos++] = dag->of->ocp >> 8;
buffer[pos++] = dag->of->ocp & 0xff;
buffer[pos++] = 0; /* reserved */
buffer[pos++] = dag->default_lifetime;
buffer[pos++] = dag->lifetime_unit >> 8;
buffer[pos++] = dag->lifetime_unit & 0xff;
/* Check if we have a prefix to send also. */
if(dag->prefix_info.length > 0) {
buffer[pos++] = RPL_DIO_SUBOPT_PREFIX_INFO;
buffer[pos++] = 30; /* always 30 bytes + 2 long */
buffer[pos++] = dag->prefix_info.length;
buffer[pos++] = dag->prefix_info.flags;
set32(buffer, pos, dag->prefix_info.lifetime);
pos += 4;
set32(buffer, pos, dag->prefix_info.lifetime);
pos += 4;
memset(&buffer[pos], 0, 4);
pos += 4;
memcpy(&buffer[pos], &dag->prefix_info.prefix, 16);
pos += 16;
PRINTF("RPL: Sending prefix info in DIO for ");
PRINT6ADDR(&dag->prefix_info.prefix);
PRINTF("\n");
} else {
PRINTF("RPL: No prefix to announce (len %d)\n",
dag->prefix_info.length);
}
/* Unicast requests get unicast replies! */
if(uc_addr == NULL) {
PRINTF("RPL: Sending a multicast-DIO with rank %u\n",
(unsigned)dag->rank);
uip_create_linklocal_rplnodes_mcast(&addr);
uip_icmp6_send(&addr, ICMP6_RPL, RPL_CODE_DIO, pos);
} else {
PRINTF("RPL: Sending unicast-DIO with rank %u to ",
(unsigned)dag->rank);
PRINT6ADDR(uc_addr);
PRINTF("\n");
uip_icmp6_send(uc_addr, ICMP6_RPL, RPL_CODE_DIO, pos);
}
}
/*---------------------------------------------------------------------------*/
static void
dao_input(void)
{
uip_ipaddr_t dao_sender_addr;
rpl_dag_t *dag;
unsigned char *buffer;
uint16_t sequence;
uint8_t instance_id;
rpl_lifetime_t lifetime;
uint8_t prefixlen;
uint8_t flags;
uint8_t subopt_type;
uint8_t pathcontrol;
uint8_t pathsequence;
uip_ipaddr_t prefix;
uip_ds6_route_t *rep;
uint8_t buffer_length;
int pos;
int len;
int i;
int learned_from;
rpl_parent_t *p;
prefixlen = 0;
uip_ipaddr_copy(&dao_sender_addr, &UIP_IP_BUF->srcipaddr);
/* Destination Advertisement Object */
PRINTF("RPL: Received a DAO from ");
PRINT6ADDR(&dao_sender_addr);
PRINTF("\n");
buffer = UIP_ICMP_PAYLOAD;
buffer_length = uip_len - uip_l2_l3_icmp_hdr_len;
#if RPL_CONF_ADJUST_LLH_LEN
buffer_length += UIP_LLH_LEN; /* Add jackdaw, minimal-net ethernet header */
#endif
pos = 0;
instance_id = buffer[pos++];
dag = rpl_get_dag(instance_id);
if(dag == NULL) {
PRINTF("RPL: Ignoring a DAO for a different RPL instance (%u)\n",
instance_id);
return;
}
lifetime = dag->default_lifetime;
flags = buffer[pos++];
/* reserved */
pos++;
sequence = buffer[pos++];
/* Is the DAGID present? */
if(flags & RPL_DAO_D_FLAG) {
/* Currently the DAG ID is ignored since we only use global
RPL Instance IDs. */
pos += 16;
}
/* Check if there are any DIO sub-options. */
i = pos;
for(; i < buffer_length; i += len) {
subopt_type = buffer[i];
if(subopt_type == RPL_DIO_SUBOPT_PAD1) {
len = 1;
} else {
/* Sub-option with a two-byte header and payload */
len = 2 + buffer[i + 1];
}
switch(subopt_type) {
case RPL_DIO_SUBOPT_TARGET:
/* handle the target option */
prefixlen = buffer[i + 3];
memset(&prefix, 0, sizeof(prefix));
memcpy(&prefix, buffer + i + 4, (prefixlen + 7) / CHAR_BIT);
break;
case RPL_DIO_SUBOPT_TRANSIT:
/* The path sequence and control are ignored. */
pathcontrol = buffer[i + 3];
pathsequence = buffer[i + 4];
lifetime = buffer[i + 5];
/* The parent address is also ignored. */
break;
}
}
PRINTF("RPL: DAO lifetime: %u, prefix length: %u prefix: ",
(unsigned)lifetime, (unsigned)prefixlen);
PRINT6ADDR(&prefix);
PRINTF("\n");
rep = uip_ds6_route_lookup(&prefix);
if(lifetime == ZERO_LIFETIME) {
/* No-Path DAO received; invoke the route purging routine. */
if(rep != NULL && rep->state.saved_lifetime == 0) {
PRINTF("RPL: Setting expiration timer for prefix ");
PRINT6ADDR(&prefix);
PRINTF("\n");
rep->state.saved_lifetime = rep->state.lifetime;
rep->state.lifetime = DAO_EXPIRATION_TIMEOUT;
}
return;
}
learned_from = uip_is_addr_mcast(&dao_sender_addr) ?
RPL_ROUTE_FROM_MULTICAST_DAO : RPL_ROUTE_FROM_UNICAST_DAO;
if(learned_from == RPL_ROUTE_FROM_UNICAST_DAO) {
/* Check whether this is a DAO forwarding loop. */
p = rpl_find_parent(dag, &dao_sender_addr);
if(p != NULL && DAG_RANK(p->rank, dag) < DAG_RANK(dag->rank, dag)) {
PRINTF("RPL: Loop detected when receiving a unicast DAO from a node with a lower rank! (%u < %u)\n",
DAG_RANK(p->rank, dag), DAG_RANK(dag->rank, dag));
p->rank = INFINITE_RANK;
p->updated = 1;
return;
}
}
if(rep == NULL) {
rep = rpl_add_route(dag, &prefix, prefixlen, &dao_sender_addr);
if(rep == NULL) {
RPL_STAT(rpl_stats.mem_overflows++);
PRINTF("RPL: Could not add a route after receiving a DAO\n");
return;
}
}
rep->state.lifetime = RPL_LIFETIME(dag, lifetime);
rep->state.learned_from = learned_from;
if(learned_from == RPL_ROUTE_FROM_UNICAST_DAO) {
if(dag->preferred_parent) {
PRINTF("RPL: Forwarding DAO to parent ");
PRINT6ADDR(&dag->preferred_parent->addr);
PRINTF("\n");
uip_icmp6_send(&dag->preferred_parent->addr,
ICMP6_RPL, RPL_CODE_DAO, buffer_length);
} else if(flags & RPL_DAO_K_FLAG) {
dao_ack_output(dag, &dao_sender_addr, sequence);
}
}
}
/*---------------------------------------------------------------------------*/
void
dao_output(rpl_parent_t *n, rpl_lifetime_t lifetime)
{
rpl_dag_t *dag;
unsigned char *buffer;
uint8_t prefixlen;
uip_ipaddr_t addr;
uip_ipaddr_t prefix;
int pos;
/* Destination Advertisement Object */
if(get_global_addr(&prefix) == 0) {
PRINTF("RPL: No global address set for this node - suppressing DAO\n");
return;
}
if(n == NULL) {
dag = rpl_get_dag(RPL_ANY_INSTANCE);
if(dag == NULL) {
PRINTF("RPL: Did not join a DAG before sending DAO\n");
return;
}
} else {
dag = n->dag;
}
buffer = UIP_ICMP_PAYLOAD;
++dao_sequence;
pos = 0;
buffer[pos++] = dag->instance_id;
#if RPL_CONF_DAO_ACK
buffer[pos++] = RPL_DAO_K_FLAG; /* DAO ACK request, no DODAGID */
#else
buffer[pos++] = 0; /* No DAO ACK request, no DODAGID */
#endif
buffer[pos++] = 0; /* reserved */
buffer[pos++] = dao_sequence & 0xff;
/* create target subopt */
prefixlen = sizeof(prefix) * CHAR_BIT;
buffer[pos++] = RPL_DIO_SUBOPT_TARGET;
buffer[pos++] = 2 + ((prefixlen + 7) / CHAR_BIT);
buffer[pos++] = 0; /* reserved */
buffer[pos++] = prefixlen;
memcpy(buffer + pos, &prefix, (prefixlen + 7) / CHAR_BIT);
pos += ((prefixlen + 7) / CHAR_BIT);
/* Create a transit information sub-option. */
buffer[pos++] = RPL_DIO_SUBOPT_TRANSIT;
buffer[pos++] = 4;
buffer[pos++] = 0; /* flags - ignored */
buffer[pos++] = 0; /* path control - ignored */
buffer[pos++] = 0; /* path seq - ignored */
buffer[pos++] = lifetime;
if(n == NULL) {
uip_create_linklocal_rplnodes_mcast(&addr);
} else {
uip_ipaddr_copy(&addr, &n->addr);
}
PRINTF("RPL: Sending DAO with prefix ");
PRINT6ADDR(&prefix);
PRINTF(" to ");
if(n != NULL) {
PRINT6ADDR(&n->addr);
} else {
PRINTF("multicast address");
}
PRINTF("\n");
uip_icmp6_send(&addr, ICMP6_RPL, RPL_CODE_DAO, pos);
}
/*---------------------------------------------------------------------------*/
static void
dao_ack_input(void)
{
unsigned char *buffer;
uint8_t buffer_length;
uint8_t instance_id;
uint8_t sequence;
uint8_t status;
buffer = UIP_ICMP_PAYLOAD;
buffer_length = uip_len - uip_l2_l3_icmp_hdr_len;
#if RPL_CONF_ADJUST_LLH_LEN
buffer_length+=UIP_LLH_LEN; //Add jackdaw, minimal-net ethernet header
#endif
instance_id = buffer[0];
sequence = buffer[2];
status = buffer[3];
PRINTF("RPL: Received a DAO ACK with sequence number %d and status %d from ",
sequence, status);
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("\n");
}
/*---------------------------------------------------------------------------*/
void
dao_ack_output(rpl_dag_t *dag, uip_ipaddr_t *dest, uint8_t sequence)
{
unsigned char *buffer;
PRINTF("RPL: Sending a DAO ACK with sequence number %d to ", sequence);
PRINT6ADDR(dest);
PRINTF("\n");
buffer = UIP_ICMP_PAYLOAD;
buffer[0] = dag->instance_id;
buffer[1] = 0;
buffer[2] = sequence;
buffer[3] = 0;
uip_icmp6_send(dest, ICMP6_RPL, RPL_CODE_DAO_ACK, 4);
}
/*---------------------------------------------------------------------------*/
void
uip_rpl_input(void)
{
PRINTF("Received an RPL control message\n");
switch(UIP_ICMP_BUF->icode) {
case RPL_CODE_DIO:
dio_input();
break;
case RPL_CODE_DIS:
dis_input();
break;
case RPL_CODE_DAO:
dao_input();
break;
case RPL_CODE_DAO_ACK:
dao_ack_input();
break;
default:
PRINTF("RPL: received an unknown ICMP6 code (%u)\n", UIP_ICMP_BUF->icode);
break;
}
uip_len = 0;
}