/** * \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 1.7 2010/05/18 16:43:56 nvt-se Exp $ */ /** * \file * ICMP6 I/O for RPL control messages. * * \author Joakim Eriksson , Nicolas Tsiftes * Contributors: Niclas Finne , Joel Hoglund , * Mathieu Pouillot */ #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 #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: %u\n", (unsigned)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 %u\n", (unsigned)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 %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) { 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 %u, my rank is %u\n", (unsigned)rank, (unsigned)dag->rank); if(rank < dag->rank) { return; } PRINTF("RPL: DAO rank: %u, lifetime: %lu, prefix length: %u\n", (unsigned)rank, (unsigned long)lifetime, (unsigned)prefixlen); memset(&prefix, 0, sizeof(prefix)); memcpy(&prefix, buffer + pos, prefixlen / CHAR_BIT); if(lifetime == ZERO_LIFETIME) { /* No-DAO received; invoke the route purging routine. */ rep = uip_ds6_route_lookup(&prefix); 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; } 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; } 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; 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; prefixlen = sizeof(prefix) * CHAR_BIT; 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); } 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); } /*---------------------------------------------------------------------------*/ 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; }