contiki/core/net/rpl/rpl-icmp6.c
2010-05-04 22:55:32 +00:00

510 lines
14 KiB
C

/**
* \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.
*
* $Id: rpl-icmp6.c,v 1.6 2010/05/04 22:55:32 nvt-se Exp $
*/
/**
* \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.h"
#include "net/rime/packetbuf.h"
#include <limits.h>
#include <string.h>
#define DEBUG DEBUG_ANNOTATE
#include "net/uip-debug.h"
#define RPL_DIO_GROUNDED 0x80
#define RPL_DIO_DEST_ADV_SUPPORTED 0x40
#define RPL_DIO_DEST_ADV_TRIGGER 0x20
#define RPL_DIO_DEST_ADV_STORED 0x10
#define RPL_DIO_DAG_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 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 */
/* Add a padding to be compliant with ICMPv6 */
buffer = UIP_ICMP_PAYLOAD;
buffer[0] = buffer[1] = buffer[2] = buffer[3] = 0;
if(addr == NULL) {
PRINTF("RPL: Sending a DIS\n");
uip_create_linklocal_allrouters_mcast(&tmpaddr);
addr = &tmpaddr;
} else {
PRINTF("RPL: Sending a unicast DIS\n");
}
uip_icmp6_send(addr, ICMP6_RPL, RPL_CODE_DIS, 4);
}
/*---------------------------------------------------------------------------*/
static void
dio_input(void)
{
unsigned char *buffer;
uint8_t buffer_length;
rpl_dio_t dio;
uint8_t subopt_type;
int i;
int len;
rpl_prefix_t prefix;
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);
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;
/* Process the DIO base option. */
i = 0;
buffer = UIP_ICMP_PAYLOAD;
dio.grounded = buffer[i] & RPL_DIO_GROUNDED;
dio.dst_adv_trigger = buffer[i] & RPL_DIO_DEST_ADV_TRIGGER;
dio.dst_adv_supported = buffer[i] & RPL_DIO_DEST_ADV_SUPPORTED;
dio.preference = buffer[i++] & RPL_DIO_DAG_PREFERENCE_MASK;
dio.sequence_number = buffer[i++];
dio.dag_rank = (buffer[i] << 8) + buffer[i + 1];
i += 2;
dio.instance_id = buffer[i++];
dio.dtsn = buffer[i++];
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 three-byte header. */
len = (buffer[i + 1] << 8) + buffer[i + 2] + 3;
}
switch(subopt_type) {
case RPL_DIO_SUBOPT_DAG_MC:
if(len < 7) {
PRINTF("RPL: Invalid DAG MC, len = %d\n", len);
return;
}
break;
case RPL_DIO_SUBOPT_DEST_PREFIX:
if(len < 9) {
PRINTF("RPL: Invalid destination prefix option, len = %d\n", len);
return;
}
prefix.preference = (buffer[3] >> 3) & 0x3;
break;
case RPL_DIO_SUBOPT_DAG_CONF:
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];
dio.dag_min_hoprankinc = buffer[i + 7];
PRINTF("RPL: DIO trickle timer: dbl=%d, min=%d red=%d maxinc=%d mininc=%d\n",
dio.dag_intdoubl, dio.dag_intmin, dio.dag_redund,
dio.dag_max_rankinc, dio.dag_min_hoprankinc);
break;
case RPL_DIO_SUBOPT_OCP:
dio.ocp = buffer[i + 3] << 8 | buffer[i + 4];
PRINTF("RPL: DAG OCP Sub-opt received OCP = %u\n", dio.ocp);
break;
}
}
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 Solicitation */
PRINTF("RPL: Sending a DIO with rank: %hu\n", dag->rank);
pos = 0;
buffer = UIP_ICMP_PAYLOAD;
buffer[0] = dag->preference;
if(dag->grounded) {
buffer[0] |= RPL_DIO_GROUNDED;
}
/* Set dst_adv_trigger and dst_adv_supported. */
buffer[0] |= RPL_DIO_DEST_ADV_SUPPORTED | RPL_DIO_DEST_ADV_TRIGGER;
buffer[1] = dag->sequence_number;
pos = 2;
buffer[pos++] = dag->rank >> 8;
buffer[pos++] = dag->rank & 0xff;
buffer[pos++] = dag->instance_id;
buffer[pos++] = dag->dtsn;
memcpy(buffer + pos, &dag->dag_id, sizeof(dag->dag_id));
pos += 16;
/* The objective function object must appear first. */
buffer[pos++] = RPL_DIO_SUBOPT_OCP;
buffer[pos++] = 0;
buffer[pos++] = 2;
buffer[pos++] = 0;
buffer[pos++] = 0;
/* alignment here ??? */
/* always add a sub-option for DAG configuration */
buffer[pos++] = RPL_DIO_SUBOPT_DAG_CONF;
buffer[pos++] = 0;
buffer[pos++] = 5;
buffer[pos++] = dag->dio_intdoubl;
buffer[pos++] = dag->dio_intmin;
buffer[pos++] = dag->dio_redundancy;
buffer[pos++] = dag->max_rankinc;
buffer[pos++] = dag->min_hoprankinc;
/* buffer[len++] = RPL_DIO_SUBOPT_PAD1; */
/* Unicast requests get unicast replies! */
if(uc_addr == NULL) {
PRINTF("RPL: Sending a multicast-DIO with rank %hu\n", dag->rank);
uip_create_linklocal_allrouters_mcast(&addr);
uip_icmp6_send(&addr, ICMP6_RPL, RPL_CODE_DIO, pos);
} else {
PRINTF("RPL: Sending unicast-DIO with rank %hu to ", dag->rank);
PRINT6ADDR(uc_addr);
PRINTF("\n");
uip_icmp6_send(uc_addr, ICMP6_RPL, RPL_CODE_DIO, pos);
}
}
/*---------------------------------------------------------------------------*/
static void
dao_input(void)
{
rpl_dag_t *dag;
unsigned char *buffer;
uint16_t sequence;
uint8_t instance_id;
uint32_t lifetime;
uint8_t rank;
uint8_t prefixlen;
uint32_t route_tag;
uip_ipaddr_t prefix;
uip_ds6_route_t *rep;
rpl_neighbor_t *n;
int pos;
/* Destination Advertisement Object */
PRINTF("RPL: Received a DAO from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("\n");
buffer = UIP_ICMP_PAYLOAD;
pos = 0;
sequence = (buffer[pos] << 8) | buffer[pos + 1];
pos += 2;
rank = (buffer[pos] << 8) | buffer[pos + 1];
pos += 2;
/* pos = 4 */
instance_id = buffer[pos++];
route_tag = buffer[pos++];
prefixlen = buffer[pos++];
/* ignore RRCount for now: rrcount = buffer[pos++]; */
pos++;
/* pos = 8 */
lifetime = get32(buffer, pos);
pos += 4;
dag = rpl_get_dag(instance_id);
if(dag == NULL) {
PRINTF("RPL: Ignoring a DAO for a different DAG instance (%u)\n",
instance_id);
return;
}
PRINTF("RPL: Incoming DAO rank is %hu, my rank is %hu\n", rank, dag->rank);
if(rank < dag->rank) {
return;
}
PRINTF("RPL: DAO rank: %u, lifetime: %lu, prefix length: %u\n", rank,
(unsigned long)lifetime, prefixlen);
memset(&prefix, 0, sizeof(prefix));
memcpy(&prefix, buffer + pos, prefixlen / CHAR_BIT);
rep = rpl_add_route(dag, &prefix, prefixlen,
&UIP_IP_BUF->srcipaddr);
if(rep == NULL) {
PRINTF("RPL: Could not add a route while receiving a DAO\n");
return;
}
if(lifetime == ZERO_LIFETIME) {
/* No-DAO received; invoke the route purging routine. */
rpl_purge_routes();
return;
}
rep->state.lifetime = lifetime;
if(uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
rep->state.learned_from = RPL_ROUTE_FROM_MULTICAST_DAO;
} else {
rep->state.learned_from = RPL_ROUTE_FROM_UNICAST_DAO;
if((n = rpl_find_best_parent(dag)) != NULL) {
PRINTF("RPL: Forwarding DAO to parent ");
PRINT6ADDR(&n->addr);
PRINTF("\n");
uip_icmp6_send(&n->addr, ICMP6_RPL, RPL_CODE_DAO,
14 + (prefixlen / CHAR_BIT));
}
}
}
/*---------------------------------------------------------------------------*/
void
dao_output(rpl_neighbor_t *n, uint32_t lifetime)
{
rpl_dag_t *dag;
unsigned char *buffer;
static uint16_t sequence;
uint8_t prefixlen;
uip_ipaddr_t addr;
uip_ipaddr_t prefix;
int pos;
/* Destination Advertisement Object */
if(n == NULL) {
dag = rpl_get_dag(RPL_ANY_INSTANCE);
if(dag == NULL) {
PRINTF("RPL: Did not join a DAG before receiving DAO\n");
return;
}
} else {
dag = n->dag;
}
buffer = UIP_ICMP_PAYLOAD;
++sequence;
pos = 0;
buffer[pos++] = sequence >> 8;
buffer[pos++] = sequence & 0xff;
PRINTF("RPL: Sending DAO with prefix ");
PRINT6ADDR(&prefix);
PRINTF(" to ");
if(n != NULL) {
PRINT6ADDR(&n->addr);
} else {
PRINTF("multicast address");
}
PRINTF("\n");
prefixlen = sizeof(dag->dag_id) * CHAR_BIT;
buffer[pos++] = dag->rank >> 8;
buffer[pos++] = dag->rank & 0xff;
/* pos = 4 */
buffer[pos++] = dag->instance_id;
/* Route tag. Unspecified in draft-ietf-roll-rpl-06. */
buffer[pos++] = 0;
buffer[pos++] = prefixlen;
/* Reverse route count. Not used because reverse routing is unscalable
beyond a few hops. */
buffer[pos++] = 0;
/* pos = 8 */
/* DAO Lifetime. */
set32(buffer, pos, lifetime);
pos += 4;
/* pos = 12 or 14 */
if(get_global_addr(&prefix) == 0) {
PRINTF("RPL: No global address set for this node - suppressing DAO\n");
return;
}
memcpy(buffer + pos, &prefix, prefixlen / CHAR_BIT);
pos += (prefixlen / CHAR_BIT);
if(n == NULL) {
uip_create_linklocal_allnodes_mcast(&addr);
} else {
uip_ipaddr_copy(&addr, &n->addr);
}
uip_icmp6_send(&addr, ICMP6_RPL, RPL_CODE_DAO, pos);
}
/*---------------------------------------------------------------------------*/
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;
default:
PRINTF("RPL: received an unknown ICMP6 code (%u)\n", UIP_ICMP_BUF->icode);
break;
}
uip_len = 0;
}