/*---------------------------------------------------------------------------*/
void
uip_ds6_neighbor_periodic(void)
{
/* Periodic processing on neighbors */
uip_ds6_nbr_t *nbr = nbr_table_head(ds6_neighbors);
while(nbr != NULL) {
switch(nbr->state) {
case NBR_REACHABLE:
if(stimer_expired(&nbr->reachable)) {
PRINTF("REACHABLE: moving to STALE (");
PRINT6ADDR(&nbr->ipaddr);
PRINTF(")\n");
nbr->state = NBR_STALE;
}
break;
#if UIP_ND6_SEND_NA
case NBR_INCOMPLETE:
if(nbr->nscount >= UIP_ND6_MAX_MULTICAST_SOLICIT) {
uip_ds6_nbr_rm(nbr);
} else if(stimer_expired(&nbr->sendns) && (uip_len == 0)) {
nbr->nscount++;
PRINTF("NBR_INCOMPLETE: NS %u\n", nbr->nscount);
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
case NBR_DELAY:
if(stimer_expired(&nbr->reachable)) {
nbr->state = NBR_PROBE;
nbr->nscount = 0;
PRINTF("DELAY: moving to PROBE\n");
stimer_set(&nbr->sendns, 0);
}
break;
case NBR_PROBE:
if(nbr->nscount >= UIP_ND6_MAX_UNICAST_SOLICIT) {
uip_ds6_defrt_t *locdefrt;
PRINTF("PROBE END\n");
if((locdefrt = uip_ds6_defrt_lookup(&nbr->ipaddr)) != NULL) {
if (!locdefrt->isinfinite) {
uip_ds6_defrt_rm(locdefrt);
}
}
uip_ds6_nbr_rm(nbr);
} else if(stimer_expired(&nbr->sendns) && (uip_len == 0)) {
nbr->nscount++;
PRINTF("PROBE: NS %u\n", nbr->nscount);
uip_nd6_ns_output(NULL, &nbr->ipaddr, &nbr->ipaddr);
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
#endif /* UIP_ND6_SEND_NA */
default:
break;
}
nbr = nbr_table_next(ds6_neighbors, nbr);
}
}
void
uip_ds6_dad(uip_ds6_addr_t *addr)
{
/* send maxdadns NS for DAD */
if(addr->dadnscount < uip_ds6_if.maxdadns) {
uip_nd6_ns_output(NULL, NULL, &addr->ipaddr);
addr->dadnscount++;
timer_set(&addr->dadtimer,
uip_ds6_if.retrans_timer / 1000 * CLOCK_SECOND);
return;
}
/*
* If we arrive here it means DAD succeeded, otherwise the dad process
* would have been interrupted in ds6_dad_ns/na_input
*/
PRINTF("DAD succeeded, ipaddr:");
PRINT6ADDR(&addr->ipaddr);
PRINTF("\n");
addr->state = ADDR_PREFERRED;
return;
}
void
tcpip_ipv6_output(void)
{
uip_ds6_nbr_t *nbr = NULL;
uip_ipaddr_t *nexthop;
if(uip_len == 0) {
return;
}
if(uip_len > UIP_LINK_MTU) {
UIP_LOG("tcpip_ipv6_output: Packet to big");
uip_len = 0;
return;
}
if(uip_is_addr_unspecified(&UIP_IP_BUF->destipaddr)) {
UIP_LOG("tcpip_ipv6_output: Destination address unspecified");
uip_len = 0;
return;
}
if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
/* Next hop determination */
nbr = NULL;
if(uip_ds6_is_addr_onlink(&UIP_IP_BUF->destipaddr)) {
nexthop = &UIP_IP_BUF->destipaddr;
} else {
uip_ds6_route_t* locrt;
locrt = uip_ds6_route_lookup(&UIP_IP_BUF->destipaddr);
if(locrt == NULL) {
if((nexthop = uip_ds6_defrt_choose()) == NULL) {
#ifdef UIP_FALLBACK_INTERFACE
PRINTF("FALLBACK: removing ext hdrs & setting proto %d %d\n",
uip_ext_len, *((uint8_t *)UIP_IP_BUF + 40));
if(uip_ext_len > 0) {
extern void remove_ext_hdr(void);
uint8_t proto = *((uint8_t *)UIP_IP_BUF + 40);
remove_ext_hdr();
/* This should be copied from the ext header... */
UIP_IP_BUF->proto = proto;
}
UIP_FALLBACK_INTERFACE.output();
#else
PRINTF("tcpip_ipv6_output: Destination off-link but no route\n");
#endif /* !UIP_FALLBACK_INTERFACE */
uip_len = 0;
return;
}
} else {
nexthop = &locrt->nexthop;
}
#if TCPIP_CONF_ANNOTATE_TRANSMISSIONS
if(nexthop != NULL) {
printf("#L %u 1; red\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
}
#endif /* TCPIP_CONF_ANNOTATE_TRANSMISSIONS */
}
/* End of next hop determination */
#if UIP_CONF_IPV6_RPL
if(rpl_update_header_final(nexthop)) {
uip_len = 0;
return;
}
#endif /* UIP_CONF_IPV6_RPL */
if((nbr = uip_ds6_nbr_lookup(nexthop)) == NULL) {
#if UIP_ND6_SEND_NA
if((nbr = uip_ds6_nbr_add(nexthop, NULL, 0, NBR_INCOMPLETE)) == NULL) {
uip_len = 0;
return;
} else {
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif
/* RFC4861, 7.2.2:
* "If the source address of the packet prompting the solicitation is the
* same as one of the addresses assigned to the outgoing interface, that
* address SHOULD be placed in the IP Source Address of the outgoing
* solicitation. Otherwise, any one of the addresses assigned to the
* interface should be used."*/
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) {
uip_nd6_ns_output(&UIP_IP_BUF->srcipaddr, NULL, &nbr->ipaddr);
} else {
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
}
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
nbr->nscount = 1;
}
#endif /* UIP_ND6_SEND_NA */
} else {
#if UIP_ND6_SEND_NA
if(nbr->state == NBR_INCOMPLETE) {
PRINTF("tcpip_ipv6_output: nbr cache entry incomplete\n");
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit and set
the destination nbr to nbr. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_len = 0;
return;
}
/* Send in parallel if we are running NUD (nbc state is either STALE,
DELAY, or PROBE). See RFC 4861, section 7.7.3 on node behavior. */
if(nbr->state == NBR_STALE) {
nbr->state = NBR_DELAY;
stimer_set(&nbr->reachable, UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
PRINTF("tcpip_ipv6_output: nbr cache entry stale moving to delay\n");
}
#endif /* UIP_ND6_SEND_NA */
tcpip_output(&nbr->lladdr);
#if UIP_CONF_IPV6_QUEUE_PKT
/*
* Send the queued packets from here, may not be 100% perfect though.
* This happens in a few cases, for example when instead of receiving a
* NA after sendiong a NS, you receive a NS with SLLAO: the entry moves
* to STALE, and you must both send a NA and the queued packet.
*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
tcpip_output(&nbr->lladdr);
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_len = 0;
return;
}
}
/* Multicast IP destination address. */
tcpip_output(NULL);
uip_len = 0;
uip_ext_len = 0;
}
void
tcpip_ipv6_output(void)
{
uip_ds6_nbr_t *nbr = NULL;
uip_ipaddr_t *nexthop;
if(uip_len == 0) {
return;
}
if(uip_len > UIP_LINK_MTU) {
UIP_LOG("tcpip_ipv6_output: Packet to big");
uip_clear_buf();
return;
}
if(uip_is_addr_unspecified(&UIP_IP_BUF->destipaddr)){
UIP_LOG("tcpip_ipv6_output: Destination address unspecified");
uip_clear_buf();
return;
}
if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
/* Next hop determination */
nbr = NULL;
/* We first check if the destination address is on our immediate
link. If so, we simply use the destination address as our
nexthop address. */
if(uip_ds6_is_addr_onlink(&UIP_IP_BUF->destipaddr)){
nexthop = &UIP_IP_BUF->destipaddr;
} else {
uip_ds6_route_t *route;
/* Check if we have a route to the destination address. */
route = uip_ds6_route_lookup(&UIP_IP_BUF->destipaddr);
/* No route was found - we send to the default route instead. */
if(route == NULL) {
PRINTF("tcpip_ipv6_output: no route found, using default route\n");
nexthop = uip_ds6_defrt_choose();
if(nexthop == NULL) {
#ifdef UIP_FALLBACK_INTERFACE
PRINTF("FALLBACK: removing ext hdrs & setting proto %d %d\n",
uip_ext_len, *((uint8_t *)UIP_IP_BUF + 40));
if(uip_ext_len > 0) {
extern void remove_ext_hdr(void);
uint8_t proto = *((uint8_t *)UIP_IP_BUF + 40);
remove_ext_hdr();
/* This should be copied from the ext header... */
UIP_IP_BUF->proto = proto;
}
/* Inform the other end that the destination is not reachable. If it's
* not informed routes might get lost unexpectedly until there's a need
* to send a new packet to the peer */
if(UIP_FALLBACK_INTERFACE.output() < 0) {
PRINTF("FALLBACK: output error. Reporting DST UNREACH\n");
uip_icmp6_error_output(ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_ADDR, 0);
uip_flags = 0;
tcpip_ipv6_output();
return;
}
#else
PRINTF("tcpip_ipv6_output: Destination off-link but no route\n");
#endif /* !UIP_FALLBACK_INTERFACE */
uip_clear_buf();
return;
}
} else {
/* A route was found, so we look up the nexthop neighbor for
the route. */
nexthop = uip_ds6_route_nexthop(route);
/* If the nexthop is dead, for example because the neighbor
never responded to link-layer acks, we drop its route. */
if(nexthop == NULL) {
#if UIP_CONF_IPV6_RPL
/* If we are running RPL, and if we are the root of the
network, we'll trigger a global repair berfore we remove
the route. */
rpl_dag_t *dag;
rpl_instance_t *instance;
dag = (rpl_dag_t *)route->state.dag;
if(dag != NULL) {
instance = dag->instance;
rpl_repair_root(instance->instance_id);
}
#endif /* UIP_CONF_IPV6_RPL */
uip_ds6_route_rm(route);
/* We don't have a nexthop to send the packet to, so we drop
it. */
return;
}
}
#if TCPIP_CONF_ANNOTATE_TRANSMISSIONS
if(nexthop != NULL) {
static uint8_t annotate_last;
static uint8_t annotate_has_last = 0;
if(annotate_has_last) {
printf("#L %u 0; red\n", annotate_last);
}
printf("#L %u 1; red\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
annotate_last = nexthop->u8[sizeof(uip_ipaddr_t) - 1];
annotate_has_last = 1;
}
#endif /* TCPIP_CONF_ANNOTATE_TRANSMISSIONS */
}
/* End of next hop determination */
#if UIP_CONF_IPV6_RPL
if(rpl_update_header_final(nexthop)) {
uip_clear_buf();
return;
}
#endif /* UIP_CONF_IPV6_RPL */
nbr = uip_ds6_nbr_lookup(nexthop);
if(nbr == NULL) {
#if UIP_ND6_SEND_NA
if((nbr = uip_ds6_nbr_add(nexthop, NULL, 0, NBR_INCOMPLETE)) == NULL) {
uip_clear_buf();
return;
} else {
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif
/* RFC4861, 7.2.2:
* "If the source address of the packet prompting the solicitation is the
* same as one of the addresses assigned to the outgoing interface, that
* address SHOULD be placed in the IP Source Address of the outgoing
* solicitation. Otherwise, any one of the addresses assigned to the
* interface should be used."*/
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)){
uip_nd6_ns_output(&UIP_IP_BUF->srcipaddr, NULL, &nbr->ipaddr);
} else {
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
}
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
nbr->nscount = 1;
/* Send the first NS try from here (multicast destination IP address). */
}
#else /* UIP_ND6_SEND_NA */
uip_len = 0;
return;
#endif /* UIP_ND6_SEND_NA */
} else {
#if UIP_ND6_SEND_NA
if(nbr->state == NBR_INCOMPLETE) {
PRINTF("tcpip_ipv6_output: nbr cache entry incomplete\n");
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit and set
the destination nbr to nbr. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_clear_buf();
return;
}
/* Send in parallel if we are running NUD (nbc state is either STALE,
DELAY, or PROBE). See RFC 4861, section 7.3.3 on node behavior. */
if(nbr->state == NBR_STALE) {
nbr->state = NBR_DELAY;
stimer_set(&nbr->reachable, UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
PRINTF("tcpip_ipv6_output: nbr cache entry stale moving to delay\n");
}
#endif /* UIP_ND6_SEND_NA */
tcpip_output(uip_ds6_nbr_get_ll(nbr));
#if UIP_CONF_IPV6_QUEUE_PKT
/*
* Send the queued packets from here, may not be 100% perfect though.
* This happens in a few cases, for example when instead of receiving a
* NA after sendiong a NS, you receive a NS with SLLAO: the entry moves
* to STALE, and you must both send a NA and the queued packet.
*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
tcpip_output(uip_ds6_nbr_get_ll(nbr));
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_clear_buf();
return;
}
}
/* Multicast IP destination address. */
tcpip_output(NULL);
uip_clear_buf();
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_periodic(void)
{
/* Periodic processing on unicast addresses */
for(locaddr = uip_ds6_if.addr_list;
locaddr < uip_ds6_if.addr_list + UIP_DS6_ADDR_NB; locaddr++) {
if(locaddr->isused) {
if((!locaddr->isinfinite) && (stimer_expired(&locaddr->vlifetime))) {
uip_ds6_addr_rm(locaddr);
#if UIP_ND6_DEF_MAXDADNS > 0
} else if((locaddr->state == ADDR_TENTATIVE)
&& (locaddr->dadnscount <= uip_ds6_if.maxdadns)
&& (timer_expired(&locaddr->dadtimer))
&& (uip_len == 0)) {
uip_ds6_dad(locaddr);
#endif /* UIP_ND6_DEF_MAXDADNS > 0 */
}
}
}
/* Periodic processing on default routers */
for(locdefrt = uip_ds6_defrt_list;
locdefrt < uip_ds6_defrt_list + UIP_DS6_DEFRT_NB; locdefrt++) {
if((locdefrt->isused) && (!locdefrt->isinfinite) &&
(stimer_expired(&(locdefrt->lifetime)))) {
uip_ds6_defrt_rm(locdefrt);
}
}
#if !UIP_CONF_ROUTER
/* Periodic processing on prefixes */
for(locprefix = uip_ds6_prefix_list;
locprefix < uip_ds6_prefix_list + UIP_DS6_PREFIX_NB;
locprefix++) {
if(locprefix->isused && !locprefix->isinfinite
&& stimer_expired(&(locprefix->vlifetime))) {
uip_ds6_prefix_rm(locprefix);
}
}
#endif /* !UIP_CONF_ROUTER */
/* Periodic processing on neighbors */
for(locnbr = uip_ds6_nbr_cache;
locnbr < uip_ds6_nbr_cache + UIP_DS6_NBR_NB;
locnbr++) {
if(locnbr->isused) {
switch(locnbr->state) {
case NBR_INCOMPLETE:
if(locnbr->nscount >= UIP_ND6_MAX_MULTICAST_SOLICIT) {
uip_ds6_nbr_rm(locnbr);
} else if(stimer_expired(&locnbr->sendns) && (uip_len == 0)) {
locnbr->nscount++;
PRINTF("NBR_INCOMPLETE: NS %u\n", locnbr->nscount);
uip_nd6_ns_output(NULL, NULL, &locnbr->ipaddr);
stimer_set(&locnbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
case NBR_REACHABLE:
if(stimer_expired(&locnbr->reachable)) {
PRINTF("REACHABLE: moving to STALE (");
PRINT6ADDR(&locnbr->ipaddr);
PRINTF(")\n");
locnbr->state = NBR_STALE;
}
break;
case NBR_DELAY:
if(stimer_expired(&locnbr->reachable)) {
locnbr->state = NBR_PROBE;
locnbr->nscount = 0;
PRINTF("DELAY: moving to PROBE\n");
stimer_set(&locnbr->sendns, 0);
}
break;
case NBR_PROBE:
if(locnbr->nscount >= UIP_ND6_MAX_UNICAST_SOLICIT) {
PRINTF("PROBE END\n");
if((locdefrt = uip_ds6_defrt_lookup(&locnbr->ipaddr)) != NULL) {
if (!locdefrt->isinfinite) {
uip_ds6_defrt_rm(locdefrt);
}
}
uip_ds6_nbr_rm(locnbr);
} else if(stimer_expired(&locnbr->sendns) && (uip_len == 0)) {
locnbr->nscount++;
PRINTF("PROBE: NS %u\n", locnbr->nscount);
uip_nd6_ns_output(NULL, &locnbr->ipaddr, &locnbr->ipaddr);
stimer_set(&locnbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
default:
break;
}
}
}
#if UIP_CONF_ROUTER & UIP_ND6_SEND_RA
/* Periodic RA sending */
if(stimer_expired(&uip_ds6_timer_ra) && (uip_len == 0)) {
uip_ds6_send_ra_periodic();
}
#endif /* UIP_CONF_ROUTER & UIP_ND6_SEND_RA */
etimer_reset(&uip_ds6_timer_periodic);
return;
}
/** Periodic processing on neighbors */
void
uip_ds6_neighbor_periodic(void)
{
uip_ds6_nbr_t *nbr = nbr_table_head(ds6_neighbors);
while(nbr != NULL) {
switch(nbr->state) {
case NBR_REACHABLE:
if(stimer_expired(&nbr->reachable)) {
#if UIP_CONF_IPV6_RPL
/* when a neighbor leave its REACHABLE state and is a default router,
instead of going to STALE state it enters DELAY state in order to
force a NUD on it. Otherwise, if there is no upward traffic, the
node never knows if the default router is still reachable. This
mimics the 6LoWPAN-ND behavior.
*/
if(uip_ds6_defrt_lookup(&nbr->ipaddr) != NULL) {
PRINTF("REACHABLE: defrt moving to DELAY (");
PRINT6ADDR(&nbr->ipaddr);
PRINTF(")\n");
nbr->state = NBR_DELAY;
stimer_set(&nbr->reachable, UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
} else {
PRINTF("REACHABLE: moving to STALE (");
PRINT6ADDR(&nbr->ipaddr);
PRINTF(")\n");
nbr->state = NBR_STALE;
}
#else /* UIP_CONF_IPV6_RPL */
PRINTF("REACHABLE: moving to STALE (");
PRINT6ADDR(&nbr->ipaddr);
PRINTF(")\n");
nbr->state = NBR_STALE;
#endif /* UIP_CONF_IPV6_RPL */
}
break;
case NBR_INCOMPLETE:
if(nbr->nscount >= UIP_ND6_MAX_MULTICAST_SOLICIT) {
uip_ds6_nbr_rm(nbr);
} else if(stimer_expired(&nbr->sendns) && (uip_len == 0)) {
nbr->nscount++;
PRINTF("NBR_INCOMPLETE: NS %u\n", nbr->nscount);
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
case NBR_DELAY:
if(stimer_expired(&nbr->reachable)) {
nbr->state = NBR_PROBE;
nbr->nscount = 0;
PRINTF("DELAY: moving to PROBE\n");
stimer_set(&nbr->sendns, 0);
}
break;
case NBR_PROBE:
if(nbr->nscount >= UIP_ND6_MAX_UNICAST_SOLICIT) {
uip_ds6_defrt_t *locdefrt;
PRINTF("PROBE END\n");
if((locdefrt = uip_ds6_defrt_lookup(&nbr->ipaddr)) != NULL) {
if (!locdefrt->isinfinite) {
uip_ds6_defrt_rm(locdefrt);
}
}
uip_ds6_nbr_rm(nbr);
} else if(stimer_expired(&nbr->sendns) && (uip_len == 0)) {
nbr->nscount++;
PRINTF("PROBE: NS %u\n", nbr->nscount);
uip_nd6_ns_output(NULL, &nbr->ipaddr, &nbr->ipaddr);
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
}
break;
default:
break;
}
nbr = nbr_table_next(ds6_neighbors, nbr);
}
}
void
tcpip_ipv6_output(void)
{
uip_ds6_nbr_t *nbr = NULL;
uip_ipaddr_t *nexthop;
uip_ds6_route_t *route = NULL;
if(uip_len == 0) {
return;
}
PRINTF("IPv6 packet send from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("\n");
if(uip_len > UIP_LINK_MTU) {
UIP_LOG("tcpip_ipv6_output: Packet to big");
uip_clear_buf();
return;
}
if(uip_is_addr_unspecified(&UIP_IP_BUF->destipaddr)){
UIP_LOG("tcpip_ipv6_output: Destination address unspecified");
uip_clear_buf();
return;
}
if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
/* Next hop determination */
nbr = NULL;
/* We first check if the destination address is on our immediate
link. If so, we simply use the destination address as our
nexthop address. */
if(uip_ds6_is_addr_onlink(&UIP_IP_BUF->destipaddr)){
nexthop = &UIP_IP_BUF->destipaddr;
} else {
/* Check if we have a route to the destination address. */
route = uip_ds6_route_lookup(&UIP_IP_BUF->destipaddr);
/* No route was found - we send to the default route instead. */
if(route == NULL) {
#if CETIC_6LBR_SMARTBRIDGE
if (uip_ipaddr_prefixcmp(&wsn_net_prefix, &UIP_IP_BUF->destipaddr, 64)) {
/* In smart-bridge mode, there is no route towards hosts on the Ethernet side
Therefore we have to check the destination and assume the host is on-link */
nexthop = &UIP_IP_BUF->destipaddr;
} else
#endif
#if CETIC_6LBR_ROUTER && UIP_CONF_IPV6_RPL
if (is_dodag_root() && uip_ipaddr_prefixcmp(&wsn_net_prefix, &UIP_IP_BUF->destipaddr, 64)) {
//In router mode, we drop packets towards unknown mote
PRINTF("Dropping wsn packet with no route\n");
uip_len = 0;
return;
} else
#endif
#if CETIC_6LBR_IP64
if(ip64_addr_is_ip64(&UIP_IP_BUF->destipaddr)) {
#if UIP_CONF_IPV6_RPL
rpl_remove_header();
#endif
IP64_CONF_UIP_FALLBACK_INTERFACE.output();
uip_len = 0;
uip_ext_len = 0;
return;
}
else
#endif
{
PRINTF("tcpip_ipv6_output: no route found, using default route\n");
nexthop = uip_ds6_defrt_choose();
}
if(nexthop == NULL) {
#ifdef UIP_FALLBACK_INTERFACE
PRINTF("FALLBACK: removing ext hdrs & setting proto %d %d\n",
uip_ext_len, *((uint8_t *)UIP_IP_BUF + 40));
if(uip_ext_len > 0) {
extern void remove_ext_hdr(void);
uint8_t proto = *((uint8_t *)UIP_IP_BUF + 40);
remove_ext_hdr();
/* This should be copied from the ext header... */
UIP_IP_BUF->proto = proto;
}
UIP_FALLBACK_INTERFACE.output();
#else
PRINTF("tcpip_ipv6_output: Destination off-link but no route\n");
#endif /* !UIP_FALLBACK_INTERFACE */
uip_clear_buf();
return;
}
} else {
/* A route was found, so we look up the nexthop neighbor for
the route. */
nexthop = uip_ds6_route_nexthop(route);
/* If the nexthop is dead, for example because the neighbor
never responded to link-layer acks, we drop its route. */
if(nexthop == NULL) {
#if UIP_CONF_IPV6_RPL
/* If we are running RPL, and if we are the root of the
network, we'll trigger a DIO before we remove
the route. */
rpl_dag_t *dag;
dag = (rpl_dag_t *)route->state.dag;
if(dag != NULL) {
rpl_reset_dio_timer(dag->instance);
}
#endif /* UIP_CONF_IPV6_RPL */
uip_ds6_route_rm(route);
/* We don't have a nexthop to send the packet to, so we drop
it. */
return;
}
}
#if TCPIP_CONF_ANNOTATE_TRANSMISSIONS
if(nexthop != NULL) {
static uint8_t annotate_last;
static uint8_t annotate_has_last = 0;
if(annotate_has_last) {
printf("#L %u 0; red\n", annotate_last);
}
printf("#L %u 1; red\n", nexthop->u8[sizeof(uip_ipaddr_t) - 1]);
annotate_last = nexthop->u8[sizeof(uip_ipaddr_t) - 1];
annotate_has_last = 1;
}
#endif /* TCPIP_CONF_ANNOTATE_TRANSMISSIONS */
}
/* End of next hop determination */
#if UIP_CONF_IPV6_RPL
if(rpl_update_header_final(nexthop)) {
uip_clear_buf();
return;
}
#endif /* UIP_CONF_IPV6_RPL */
nbr = uip_ds6_nbr_lookup(nexthop);
if(nbr == NULL) {
#if UIP_ND6_SEND_NA
#if CETIC_6LBR && UIP_CONF_IPV6_RPL
/* Don't perform NUD if it has been disabled for WSN */
if((nvm_data.global_flags & CETIC_GLOBAL_DISABLE_WSN_NUD) != 0 &&
uip_ipaddr_prefixcmp(&wsn_net_prefix, &UIP_IP_BUF->destipaddr, 64) &&
route != NULL) {
uip_clear_buf();
return;
}
#endif
if((nbr = uip_ds6_nbr_add(nexthop, NULL, 0, NBR_INCOMPLETE)) == NULL) {
uip_clear_buf();
return;
} else {
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif
/* RFC4861, 7.2.2:
* "If the source address of the packet prompting the solicitation is the
* same as one of the addresses assigned to the outgoing interface, that
* address SHOULD be placed in the IP Source Address of the outgoing
* solicitation. Otherwise, any one of the addresses assigned to the
* interface should be used."*/
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)){
uip_nd6_ns_output(&UIP_IP_BUF->srcipaddr, NULL, &nbr->ipaddr);
} else {
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
}
stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
nbr->nscount = 1;
/* Send the first NS try from here (multicast destination IP address). */
}
#else /* UIP_ND6_SEND_NA */
uip_len = 0;
return;
#endif /* UIP_ND6_SEND_NA */
} else {
#if UIP_ND6_SEND_NA
if(nbr->state == NBR_INCOMPLETE) {
PRINTF("tcpip_ipv6_output: nbr cache entry incomplete\n");
#if UIP_CONF_IPV6_QUEUE_PKT
/* Copy outgoing pkt in the queuing buffer for later transmit and set
the destination nbr to nbr. */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_clear_buf();
return;
}
/* Send in parallel if we are running NUD (nbc state is either STALE,
DELAY, or PROBE). See RFC 4861, section 7.3.3 on node behavior. */
#if CETIC_6LBR && UIP_CONF_IPV6_RPL
/* Don't update nbr state if we don't want to perform NUD for WSN */
if((nvm_data.global_flags & CETIC_GLOBAL_DISABLE_WSN_NUD) == 0 ||
!uip_ipaddr_prefixcmp(&wsn_net_prefix, &UIP_IP_BUF->destipaddr, 64) ||
route == NULL)
#endif
if(nbr->state == NBR_STALE) {
nbr->state = NBR_DELAY;
stimer_set(&nbr->reachable, UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
PRINTF("tcpip_ipv6_output: nbr cache entry stale moving to delay\n");
}
#endif /* UIP_ND6_SEND_NA */
tcpip_output(uip_ds6_nbr_get_ll(nbr));
#if UIP_CONF_IPV6_QUEUE_PKT
/*
* Send the queued packets from here, may not be 100% perfect though.
* This happens in a few cases, for example when instead of receiving a
* NA after sendiong a NS, you receive a NS with SLLAO: the entry moves
* to STALE, and you must both send a NA and the queued packet.
*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
tcpip_output(uip_ds6_nbr_get_ll(nbr));
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_clear_buf();
return;
}
}
/* Multicast IP destination address. */
tcpip_output(NULL);
uip_clear_buf();
}
/*---------------------------------------------------------------------------*/
void
uip_ds6_periodic(void)
{
/* This flag signals whether we allow or not to send a packet in the current
* invocation. */
u8_t allow_output = 1;
/* minimum lifetime */
min_lifetime = 0xFFFFFFFF;
/* router with minimum lifetime */
min_defrt = NULL;
/* Periodic processing on registrations */
for(locreg = uip_ds6_reg_list;
locreg < uip_ds6_reg_list + UIP_DS6_REG_LIST_SIZE; locreg++) {
if (locreg->isused) {
if (stimer_expired(&locreg->reg_lifetime)) {
uip_ds6_reg_rm(locreg);
} else if (allow_output) {
/* If no output is allowed, it is pointless to enter here in this invocation */
if (uip_ds6_if.registration_in_progress) {
/* There is a registration in progress */
if ((locreg == uip_ds6_if.registration_in_progress) &&
(timer_expired(&locreg->registration_timer))) {
/* We already sent a NS message for this address but there has been no response */
if(locreg->reg_count >= UIP_ND6_MAX_UNICAST_SOLICIT) {
/* NUD failed. Signal the need for next-hop determination by deleting the
* NCE (RFC 4861) */
uip_ds6_reg_rm(locreg);
/* And then, delete neighbor and corresponding router (as hosts only keep
* NCEs for routers in 6lowpan-nd) */
locnbr = uip_ds6_nbr_lookup(&locreg->defrt->ipaddr);
uip_ds6_nbr_rm(locnbr);
uip_ds6_defrt_rm(locreg->defrt);
/* Since we are deleting a default router, we must delete also all
* registrations with that router.
* Be careful here, uip_ds6_reg_cleanup_defrt() modifies the value of locreg!*/
uip_ds6_reg_cleanup_defrt(locreg->defrt);
/* We will also need to start sending RS, as specified in I-D.ietf-6lowpan-nd
* for NUD failure case */
uip_ds6_send_rs(NULL);
uip_ds6_if.registration_in_progress = NULL;
} else {
locreg->reg_count++;
timer_restart(&locreg->registration_timer);
uip_nd6_ns_output(&locreg->addr->ipaddr, &locreg->defrt->ipaddr,
&locreg->defrt->ipaddr, 1, UIP_ND6_REGISTRATION_LIFETIME);
}
allow_output = 0; /* Prevent this invocation from sending anything else */
}
} else {
/* There are no registrations in progress, let's see this entry needs (re)registration
* or deletion */
if ((locreg->state == REG_GARBAGE_COLLECTIBLE) ||
(locreg->state == REG_TO_BE_UNREGISTERED) ||
((locreg->state == REG_REGISTERED) &&
(stimer_remaining(&locreg->reg_lifetime) < stimer_elapsed(&locreg->reg_lifetime)))) {
/* Issue (re)registration */
uip_ds6_if.registration_in_progress = locreg;
locreg->reg_count++;
timer_set(&locreg->registration_timer, (uip_ds6_if.retrans_timer / 1000) * (CLOCK_SECOND /* FIXME @@@jwg!!!!*/+250));
if (locreg->state == REG_TO_BE_UNREGISTERED) {
uip_nd6_ns_output(&locreg->addr->ipaddr, &locreg->defrt->ipaddr,
&locreg->defrt->ipaddr, 1, 0);
} else {
uip_nd6_ns_output(&locreg->addr->ipaddr, &locreg->defrt->ipaddr,
&locreg->defrt->ipaddr, 1, UIP_ND6_REGISTRATION_LIFETIME);
}
allow_output = 0; /* Prevent this invocation from sending anything else */
}
}
}
}
}
/* Periodic processing on unicast addresses */
for(locaddr = uip_ds6_if.addr_list;
locaddr < uip_ds6_if.addr_list + UIP_DS6_ADDR_NB; locaddr++) {
if(locaddr->isused) {
if((!locaddr->isinfinite) && (stimer_expired(&locaddr->vlifetime))) {
uip_ds6_addr_rm(locaddr);
} else if (allow_output) {
if (stimer_remaining(&locaddr->vlifetime) < min_lifetime) {
min_lifetime = stimer_remaining(&locaddr->vlifetime);
min_defrt = locaddr->defrt;
}
}
}
}
/* Periodic processing on default routers */
if (uip_ds6_defrt_choose() == NULL) {
if (allow_output) {
/* If default router list is empty, start sending RS */
uip_ds6_send_rs(NULL);
allow_output = 0; /* Prevent this invocation from sending anything else */
}
} else {
for(locdefrt = uip_ds6_defrt_list;
locdefrt < uip_ds6_defrt_list + UIP_DS6_DEFRT_NB; locdefrt++) {
if((locdefrt->isused) && (!locdefrt->isinfinite)) {
if (stimer_expired(&(locdefrt->lifetime))) {
uip_ds6_defrt_rm(locdefrt);
/* If default router list is empty, we will start sending RS in
* the next invocation of ds6_periodic() */
} else {
if (allow_output) {
if (stimer_remaining(&locdefrt->lifetime) < min_lifetime) {
min_lifetime = stimer_remaining(&locdefrt->lifetime);
min_defrt = locdefrt;
}
}
}
}
}
}
#if !UIP_CONF_ROUTER
/* Periodic processing on prefixes */
for (locprefix = uip_ds6_prefix_list;
locprefix < uip_ds6_prefix_list + UIP_DS6_PREFIX_NB; locprefix++) {
if((locprefix->isused) && (!locprefix->isinfinite)) {
if (stimer_expired(&locprefix->vlifetime)) {
uip_ds6_prefix_rm(locprefix);
} else if (allow_output) {
if (stimer_remaining(&locprefix->vlifetime) < min_lifetime) {
min_lifetime = stimer_remaining(&locprefix->vlifetime);
min_defrt = locprefix->defrt;
}
}
}
}
#endif /* !UIP_CONF_ROUTER */
#if CONF_6LOWPAN_ND_6CO
/* Periodic processing on contexts */
for(loccontext = uip_ds6_addr_context_table;
loccontext < uip_ds6_addr_context_table + SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; loccontext++) {
if(loccontext->state != NOT_IN_USE) {
if (stimer_expired(&loccontext->vlifetime)) {
if (loccontext->state != EXPIRED) {
loccontext->state = IN_USE_UNCOMPRESS_ONLY;
stimer_set(&loccontext->vlifetime, 2 * loccontext->defrt_lifetime);
} else {
uip_ds6_context_rm(loccontext);
}
} else if (allow_output) {
if (stimer_remaining(&loccontext->vlifetime) < min_lifetime) {
min_lifetime = stimer_remaining(&loccontext->vlifetime);
min_defrt = loccontext->defrt;
}
}
}
}
#endif /* CONF_6LOWPAN_ND_6CO */
/* Start sending RS well before the minimum of the lifetimes (def. router,
* context, or prefix) expires */
if ((allow_output) && (min_lifetime < UIP_DS6_LIFETIME_THRESHOLD)) {
/* Start sending RSs to the router with minimum lifetime (if possible) */
uip_ds6_send_rs(min_defrt);
allow_output = 0;
}
/* Periodic processing on neighbors */
for(locnbr = uip_ds6_nbr_cache; locnbr < uip_ds6_nbr_cache + UIP_DS6_NBR_NB;
locnbr++) {
if(locnbr->isused) {
switch (locnbr->state) {
#if UIP_CONF_ROUTER
/* There can not be INCOMPLETE NCEs in a host in 6lowpan-nd */
case NBR_INCOMPLETE:
if (allow_output) {
if(locnbr->nscount >= UIP_ND6_MAX_MULTICAST_SOLICIT) {
uip_ds6_nbr_rm(locnbr);
} else if(stimer_expired(&(locnbr->sendns))) {
locnbr->nscount++;
PRINTF("NBR_INCOMPLETE: NS %u\n", locnbr->nscount);
uip_nd6_ns_output(NULL, NULL, &locnbr->ipaddr);
stimer_set(&(locnbr->sendns), uip_ds6_if.retrans_timer / 1000);
allow_output = 0;
}
}
break;
#endif /* UIP_CONF_ROUTER */
case NBR_REACHABLE:
if(stimer_expired(&(locnbr->reachable))) {
PRINTF("REACHABLE: moving to STALE (");
PRINT6ADDR(&locnbr->ipaddr);
PRINTF(")\n");
locnbr->state = NBR_STALE;
NEIGHBOR_STATE_CHANGED(locnbr);
}
break;
case NBR_DELAY:
if (allow_output) {
if(stimer_expired(&(locnbr->reachable))) {
locnbr->state = NBR_PROBE;
locnbr->nscount = 1;
NEIGHBOR_STATE_CHANGED(locnbr);
PRINTF("DELAY: moving to PROBE + NS %u\n", locnbr->nscount);
uip_nd6_ns_output(NULL, &locnbr->ipaddr, &locnbr->ipaddr, 0, 0);
stimer_set(&(locnbr->sendns), uip_ds6_if.retrans_timer / 1000);
allow_output = 0;
}
}
break;
case NBR_PROBE:
if (allow_output) {
if(locnbr->nscount >= UIP_ND6_MAX_UNICAST_SOLICIT) {
PRINTF("PROBE END \n");
if((locdefrt = uip_ds6_defrt_lookup(&locnbr->ipaddr)) != NULL) {
uip_ds6_defrt_rm(locdefrt);
}
uip_ds6_nbr_rm(locnbr);
} else if(stimer_expired(&(locnbr->sendns))) {
locnbr->nscount++;
PRINTF("PROBE: NS %u\n", locnbr->nscount);
uip_nd6_ns_output(NULL, &locnbr->ipaddr, &locnbr->ipaddr, 0, 0);
stimer_set(&(locnbr->sendns), uip_ds6_if.retrans_timer / 1000);
allow_output = 0;
}
}
break;
default:
break;
}
}
}
#if UIP_CONF_ROUTER & UIP_ND6_SEND_RA
/* Periodic RA sending */
if(stimer_expired(&uip_ds6_timer_ra)) {
uip_ds6_send_ra_periodic();
}
#endif /* UIP_CONF_ROUTER & UIP_ND6_SEND_RA */
etimer_reset(&uip_ds6_timer_periodic);
return;
}
void
tcpip_ipv6_output(void)
{
static uip_ds6_nbr_t *nbr = NULL;
static uip_ipaddr_t* nexthop;
if(uip_len == 0) {
return;
}
if(uip_len > UIP_LINK_MTU) {
UIP_LOG("tcpip_ipv6_output: Packet to big");
uip_len = 0;
return;
}
if(uip_is_addr_unspecified(&UIP_IP_BUF->destipaddr)) {
UIP_LOG("tcpip_ipv6_output: Destination address unspecified");
uip_len = 0;
return;
}
if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
/* Next hop determination */
nbr = NULL;
if(uip_ds6_is_addr_onlink(&UIP_IP_BUF->destipaddr)) {
nexthop = &UIP_IP_BUF->destipaddr;
} else {
uip_ds6_route_t* locrt;
locrt = uip_ds6_route_lookup(&UIP_IP_BUF->destipaddr);
if(locrt == NULL) {
if((nexthop = uip_ds6_defrt_choose()) == NULL) {
#ifdef UIP_FALLBACK_INTERFACE
UIP_FALLBACK_INTERFACE.output();
#else
PRINTF("tcpip_ipv6_output: Destination off-link but no route\n");
#endif
uip_len = 0;
return;
}
} else {
nexthop = &locrt->nexthop;
}
}
/* end of next hop determination */
if((nbr = uip_ds6_nbr_lookup(nexthop)) == NULL) {
// printf("add1 %d\n", nexthop->u8[15]);
if((nbr = uip_ds6_nbr_add(nexthop, NULL, 0, NBR_INCOMPLETE)) == NULL) {
// printf("add n\n");
uip_len = 0;
return;
} else {
#if UIP_CONF_IPV6_QUEUE_PKT
/* copy outgoing pkt in the queuing buffer for later transmmit */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
#endif
/* RFC4861, 7.2.2:
* "If the source address of the packet prompting the solicitation is the
* same as one of the addresses assigned to the outgoing interface, that
* address SHOULD be placed in the IP Source Address of the outgoing
* solicitation. Otherwise, any one of the addresses assigned to the
* interface should be used."*/
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) {
uip_nd6_ns_output(&UIP_IP_BUF->srcipaddr, NULL, &nbr->ipaddr);
} else {
uip_nd6_ns_output(NULL, NULL, &nbr->ipaddr);
}
stimer_set(&(nbr->sendns), uip_ds6_if.retrans_timer / 1000);
nbr->nscount = 1;
}
} else {
if(nbr->state == NBR_INCOMPLETE) {
PRINTF("tcpip_ipv6_output: nbr cache entry incomplete\n");
#if UIP_CONF_IPV6_QUEUE_PKT
/* copy outgoing pkt in the queuing buffer for later transmmit and set
the destination nbr to nbr */
if(uip_packetqueue_alloc(&nbr->packethandle, UIP_DS6_NBR_PACKET_LIFETIME) != NULL) {
memcpy(uip_packetqueue_buf(&nbr->packethandle), UIP_IP_BUF, uip_len);
uip_packetqueue_set_buflen(&nbr->packethandle, uip_len);
}
/* memcpy(nbr->queue_buf, UIP_IP_BUF, uip_len);
nbr->queue_buf_len = uip_len;*/
uip_len = 0;
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
return;
}
/* if running NUD (nbc->state == STALE, DELAY, or PROBE ) keep
sending in parallel see rfc 4861 Node behavior in section 7.7.3*/
if(nbr->state == NBR_STALE) {
nbr->state = NBR_DELAY;
stimer_set(&(nbr->reachable),
UIP_ND6_DELAY_FIRST_PROBE_TIME);
nbr->nscount = 0;
PRINTF("tcpip_ipv6_output: nbr cache entry stale moving to delay\n");
}
stimer_set(&(nbr->sendns),
uip_ds6_if.retrans_timer / 1000);
tcpip_output(&(nbr->lladdr));
#if UIP_CONF_IPV6_QUEUE_PKT
/* Send the queued packets from here, may not be 100% perfect though.
* This happens in a few cases, for example when instead of receiving a
* NA after sendiong a NS, you receive a NS with SLLAO: the entry moves
*to STALE, and you must both send a NA and the queued packet
*/
/* if(nbr->queue_buf_len != 0) {
uip_len = nbr->queue_buf_len;
memcpy(UIP_IP_BUF, nbr->queue_buf, uip_len);
nbr->queue_buf_len = 0;
tcpip_output(&(nbr->lladdr));
}*/
if(uip_packetqueue_buflen(&nbr->packethandle) != 0) {
uip_len = uip_packetqueue_buflen(&nbr->packethandle);
memcpy(UIP_IP_BUF, uip_packetqueue_buf(&nbr->packethandle), uip_len);
uip_packetqueue_free(&nbr->packethandle);
tcpip_output(&(nbr->lladdr));
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT*/
uip_len = 0;
return;
}
}
/*multicast IP destination address */
tcpip_output(NULL);
uip_len = 0;
uip_ext_len = 0;
}