/**
* Neighbor Advertisement Processing
*
* we might have to send a pkt that had been buffered while address
* resolution was performed (if we support buffering, see UIP_CONF_QUEUE_PKT)
*
* As per RFC 4861, on link layer that have addresses, TLLAO options MUST be
* included when responding to multicast solicitations, SHOULD be included in
* response to unicast (here we assume it is for now)
*
* NA can be received after sending NS for DAD, Address resolution or NUD. Can
* be unsolicited as well.
* It can trigger update of the state of the neighbor in the neighbor cache,
* router in the router list.
* If the NS was for DAD, it means DAD failed
*
*/
static void
na_input(void)
{
#if CETIC_6LBR_SMARTBRIDGE
uip_ds6_route_t * route;
#endif
uint8_t is_llchange;
uint8_t is_router;
uint8_t is_solicited;
uint8_t is_override;
PRINTF("Received NA from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("with target address");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NA_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
/*
* booleans. the three last one are not 0 or 1 but 0 or 0x80, 0x40, 0x20
* but it works. Be careful though, do not use tests such as is_router == 1
*/
is_llchange = 0;
is_router = ((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_ROUTER));
is_solicited =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_SOLICITED));
is_override =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_OVERRIDE));
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(UIP_ICMP_BUF->icode != 0) ||
(uip_is_addr_mcast(&UIP_ND6_NA_BUF->tgtipaddr)) ||
(is_solicited && uip_is_addr_mcast(&UIP_IP_BUF->destipaddr))) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Options processing: we handle TLLAO, and must ignore others */
nd6_opt_offset = UIP_ND6_NA_LEN;
nd6_opt_llao = NULL;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_TLLAO:
nd6_opt_llao = (uint8_t *)UIP_ND6_OPT_HDR_BUF;
break;
default:
PRINTF("ND option not supported in NA\n");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
#if CETIC_6LBR_SMARTBRIDGE
/* Address Advertisement */
if ( (nvm_data.mode & CETIC_MODE_SMART_MULTI_BR) != 0 ) {
if (uip_is_addr_mcast(&UIP_IP_BUF->destipaddr) && uip_is_mcast_group_id_all_nodes(&UIP_IP_BUF->destipaddr)) {
LOG6LBR_6ADDR(INFO, &UIP_ND6_NA_BUF->tgtipaddr, "Received purge NA for ");
#if CETIC_NODE_INFO
node_info_rm_by_addr(&UIP_ND6_NA_BUF->tgtipaddr);
#endif
route = uip_ds6_route_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
if (route != NULL ) {
uip_ds6_route_rm(route);
}
goto discard;
}
}
#endif
addr = uip_ds6_addr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
/* Message processing, including TLLAO if any */
if(addr != NULL) {
#if UIP_ND6_DEF_MAXDADNS > 0
if(addr->state == ADDR_TENTATIVE) {
uip_ds6_dad_failed(addr);
}
#endif /*UIP_ND6_DEF_MAXDADNS > 0 */
PRINTF("NA received is bad\n");
goto discard;
} else {
uip_lladdr_t *lladdr;
nbr = uip_ds6_nbr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
if(nbr == NULL) {
goto discard;
}
if(nd6_opt_llao != 0) {
is_llchange =
memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], (void *)lladdr,
UIP_LLADDR_LEN);
}
if(nbr->state == NBR_INCOMPLETE) {
if(nd6_opt_llao == NULL) {
goto discard;
}
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
if(is_solicited) {
nbr->state = NBR_REACHABLE;
nbr->nscount = 0;
/* reachable time is stored in ms */
stimer_set(&(nbr->reachable), uip_ds6_if.reachable_time / 1000);
} else {
nbr->state = NBR_STALE;
}
nbr->isrouter = is_router;
} else {
if(!is_override && is_llchange) {
if(nbr->state == NBR_REACHABLE) {
nbr->state = NBR_STALE;
}
goto discard;
} else {
if(is_override || (!is_override && nd6_opt_llao != 0 && !is_llchange)
|| nd6_opt_llao == 0) {
if(nd6_opt_llao != 0) {
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
}
if(is_solicited) {
nbr->state = NBR_REACHABLE;
/* reachable time is stored in ms */
stimer_set(&(nbr->reachable), uip_ds6_if.reachable_time / 1000);
} else {
if(nd6_opt_llao != 0 && is_llchange) {
nbr->state = NBR_STALE;
}
}
}
}
if(nbr->isrouter && !is_router) {
defrt = uip_ds6_defrt_lookup(&UIP_IP_BUF->srcipaddr);
if(defrt != NULL) {
uip_ds6_defrt_rm(defrt);
}
}
nbr->isrouter = is_router;
}
}
#if UIP_CONF_IPV6_QUEUE_PKT
/* The nbr is now reachable, check if we had buffered a pkt for it */
/*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;
return;
}*/
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);
return;
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT */
discard:
uip_clear_buf();
return;
}
/**
* Neighbor Advertisement Processing
*
* we might have to send a pkt that had been buffered while address
* resolution was performed (if we support buffering, see UIP_CONF_QUEUE_PKT)
*
* As per RFC 4861, on link layer that have addresses, TLLAO options MUST be
* included when responding to multicast solicitations, SHOULD be included in
* response to unicast (here we assume it is for now)
*
* NA can be received after sending NS for DAD, Address resolution or NUD. Can
* be unsolicited as well.
* It can trigger update of the state of the neighbor in the neighbor cache,
* router in the router list.
* If the NS was for DAD, it means DAD failed
*
*/
static void
na_input(void)
{
uint8_t is_llchange;
uint8_t is_router;
uint8_t is_solicited;
uint8_t is_override;
uip_lladdr_t lladdr_aligned;
PRINTF("Received NA from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF(" with target address ");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NA_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
/*
* booleans. the three last one are not 0 or 1 but 0 or 0x80, 0x40, 0x20
* but it works. Be careful though, do not use tests such as is_router == 1
*/
is_llchange = 0;
is_router = ((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_ROUTER));
is_solicited =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_SOLICITED));
is_override =
((UIP_ND6_NA_BUF->flagsreserved & UIP_ND6_NA_FLAG_OVERRIDE));
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(UIP_ICMP_BUF->icode != 0) ||
(uip_is_addr_mcast(&UIP_ND6_NA_BUF->tgtipaddr)) ||
(is_solicited && uip_is_addr_mcast(&UIP_IP_BUF->destipaddr))) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Options processing: we handle TLLAO, and must ignore others */
nd6_opt_offset = UIP_ND6_NA_LEN;
nd6_opt_llao = NULL;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NA received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_TLLAO:
nd6_opt_llao = (uint8_t *)UIP_ND6_OPT_HDR_BUF;
break;
default:
PRINTF("ND option not supported in NA\n");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
addr = uip_ds6_addr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
/* Message processing, including TLLAO if any */
if(addr != NULL) {
#if UIP_ND6_DEF_MAXDADNS > 0
if(addr->state == ADDR_TENTATIVE) {
uip_ds6_dad_failed(addr);
}
#endif /*UIP_ND6_DEF_MAXDADNS > 0 */
PRINTF("NA received is bad\n");
goto discard;
} else {
const uip_lladdr_t *lladdr;
nbr = uip_ds6_nbr_lookup(&UIP_ND6_NA_BUF->tgtipaddr);
if(nbr == NULL) {
goto discard;
}
lladdr = uip_ds6_nbr_get_ll(nbr);
if(lladdr == NULL) {
goto discard;
}
if(nd6_opt_llao != NULL) {
is_llchange =
memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], lladdr,
UIP_LLADDR_LEN);
}
if(nbr->state == NBR_INCOMPLETE) {
if(nd6_opt_llao == NULL || !extract_lladdr_from_llao_aligned(&lladdr_aligned)) {
goto discard;
}
if(nbr_table_update_lladdr((const linkaddr_t *)lladdr, (const linkaddr_t *)&lladdr_aligned, 1) == 0) {
/* failed to update the lladdr */
goto discard;
}
/* Note: No need to refresh the state of the nbr here.
* It has already been refreshed upon receiving the unicast IPv6 ND packet.
* See: uip_ds6_nbr_refresh_reachable_state()
*/
if(!is_solicited) {
nbr->state = NBR_STALE;
}
nbr->isrouter = is_router;
} else { /* NBR is not INCOMPLETE */
if(!is_override && is_llchange) {
if(nbr->state == NBR_REACHABLE) {
nbr->state = NBR_STALE;
}
goto discard;
} else {
/**
* If this is an cache override, or same lladdr, or no llao -
* do updates of nbr states.
*/
if(is_override || !is_llchange || nd6_opt_llao == NULL) {
if(nd6_opt_llao != NULL && is_llchange) {
if(!extract_lladdr_from_llao_aligned(&lladdr_aligned) ||
nbr_table_update_lladdr((const linkaddr_t *) lladdr, (const linkaddr_t *) &lladdr_aligned, 1) == 0) {
/* failed to update the lladdr */
goto discard;
}
}
/* Note: No need to refresh the state of the nbr here.
* It has already been refreshed upon receiving the unicast IPv6 ND packet.
* See: uip_ds6_nbr_refresh_reachable_state()
*/
}
}
if(nbr->isrouter && !is_router) {
defrt = uip_ds6_defrt_lookup(&UIP_IP_BUF->srcipaddr);
if(defrt != NULL) {
uip_ds6_defrt_rm(defrt);
}
}
nbr->isrouter = is_router;
}
}
#if UIP_CONF_IPV6_QUEUE_PKT
/* The nbr is now reachable, check if we had buffered a pkt for it */
/*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;
return;
}*/
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);
return;
}
#endif /*UIP_CONF_IPV6_QUEUE_PKT */
discard:
uip_clear_buf();
return;
}
static void
ns_input(void)
{
uint8_t flags;
#if CETIC_6LBR_SMARTBRIDGE
uip_ds6_route_t * route;
#endif
uip_ipaddr_t tgtipaddr;
PRINTF("Received NS from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF(" with target address");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NS_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(uip_is_addr_mcast(&UIP_ND6_NS_BUF->tgtipaddr)) ||
(UIP_ICMP_BUF->icode != 0)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
/* Options processing */
nd6_opt_llao = NULL;
nd6_opt_offset = UIP_ND6_NS_LEN;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_SLLAO:
nd6_opt_llao = &uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset];
#if UIP_CONF_IPV6_CHECKS
/* There must be NO option in a DAD NS */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
} else {
#endif /*UIP_CONF_IPV6_CHECKS */
nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
if(nbr == NULL) {
/* Copy link address to a uip_lladdr_t first
* to ensure the second argument to uip_ds6_nbr_add is word-aligned */
uip_lladdr_t lladdr;
memcpy(&lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], UIP_LLADDR_LEN);
uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr, &lladdr, 0, NBR_STALE);
} else {
uip_lladdr_t *lladdr = (uip_lladdr_t *)uip_ds6_nbr_get_ll(nbr);
if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
lladdr, UIP_LLADDR_LEN) != 0) {
memcpy(lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET], UIP_LLADDR_LEN);
nbr->state = NBR_STALE;
} else {
if(nbr->state == NBR_INCOMPLETE) {
nbr->state = NBR_STALE;
}
}
}
#if UIP_CONF_IPV6_CHECKS
}
#endif /*UIP_CONF_IPV6_CHECKS */
break;
default:
PRINTF("ND option not supported in NS");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
memcpy(&tgtipaddr, &UIP_ND6_NS_BUF->tgtipaddr, sizeof(tgtipaddr));
addr = uip_ds6_addr_lookup(&tgtipaddr);
#if CETIC_6LBR_SMARTBRIDGE
//ND Proxy implementation
if ( addr == NULL ) {
if ( (route = uip_ds6_route_lookup(&tgtipaddr)) != NULL ) {
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
uip_create_linklocal_allnodes_mcast(&tgtipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &tgtipaddr);
flags = UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
}
}
}
#endif
if(addr != NULL) {
#if UIP_ND6_DEF_MAXDADNS > 0
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
#if UIP_CONF_IPV6_CHECKS
if(!uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
if(addr->state != ADDR_TENTATIVE) {
uip_create_linklocal_allnodes_mcast(&UIP_IP_BUF->destipaddr);
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
flags = UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
/** \todo if I sent a NS before him, I win */
uip_ds6_dad_failed(addr);
goto discard;
}
#else /* UIP_ND6_DEF_MAXDADNS > 0 */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
goto discard;
#endif /* UIP_ND6_DEF_MAXDADNS > 0 */
}
#if UIP_CONF_IPV6_CHECKS
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) {
/**
* \NOTE do we do something here? we both are using the same address.
* If we are doing dad, we could cancel it, though we should receive a
* NA in response of DAD NS we sent, hence DAD will fail anyway. If we
* were not doing DAD, it means there is a duplicate in the network!
*/
PRINTF("NS received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Address resolution case */
if(uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
}
/* NUD CASE */
if(uip_ds6_addr_lookup(&UIP_IP_BUF->destipaddr) == addr) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
#if UIP_CONF_IPV6_CHECKS
PRINTF("NS received is bad\n");
goto discard;
#endif /* UIP_CONF_IPV6_CHECKS */
}
} else {
goto discard;
}
create_na:
/* If the node is a router it should set R flag in NAs */
#if UIP_CONF_ROUTER
flags = flags | UIP_ND6_NA_FLAG_ROUTER;
#endif
uip_ext_len = 0;
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
UIP_ICMP_BUF->type = ICMP6_NA;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_NA_BUF->flagsreserved = flags;
memcpy(&UIP_ND6_NA_BUF->tgtipaddr, &tgtipaddr, sizeof(uip_ipaddr_t));
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_NA_LEN],
UIP_ND6_OPT_TLLAO);
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
uip_len =
UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending NA to ");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF(" from ");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF(" with target address ");
PRINT6ADDR(&UIP_ND6_NA_BUF->tgtipaddr);
PRINTF("\n");
return;
discard:
uip_clear_buf();
return;
}
#endif /* UIP_ND6_SEND_NA */
/*------------------------------------------------------------------*/
void
uip_nd6_ns_output(uip_ipaddr_t * src, uip_ipaddr_t * dest, uip_ipaddr_t * tgt)
{
uip_ext_len = 0;
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
if(dest == NULL) {
uip_create_solicited_node(tgt, &UIP_IP_BUF->destipaddr);
} else {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, dest);
}
UIP_ICMP_BUF->type = ICMP6_NS;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_NS_BUF->reserved = 0;
uip_ipaddr_copy((uip_ipaddr_t *) &UIP_ND6_NS_BUF->tgtipaddr, tgt);
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
/*
* check if we add a SLLAO option: for DAD, MUST NOT, for NUD, MAY
* (here yes), for Address resolution , MUST
*/
if(!(uip_ds6_is_my_addr(tgt))) {
if(src != NULL) {
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, src);
} else {
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
}
if (uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("Dropping NS due to no suitable source address\n");
uip_clear_buf();
return;
}
UIP_IP_BUF->len[1] =
UIP_ICMPH_LEN + UIP_ND6_NS_LEN + UIP_ND6_OPT_LLAO_LEN;
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_NS_LEN],
UIP_ND6_OPT_SLLAO);
uip_len =
UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NS_LEN + UIP_ND6_OPT_LLAO_LEN;
} else {
uip_create_unspecified(&UIP_IP_BUF->srcipaddr);
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_NS_LEN;
uip_len = UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NS_LEN;
}
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending NS to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("with target address");
PRINT6ADDR(tgt);
PRINTF("\n");
return;
}
void
uip_nd6_ns_input(void)
{
u8_t flags;
PRINTF("Received NS from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("with target address");
PRINT6ADDR((uip_ipaddr_t *) (&UIP_ND6_NS_BUF->tgtipaddr));
PRINTF("\n");
UIP_STAT(++uip_stat.nd6.recv);
#if UIP_CONF_IPV6_CHECKS
if((UIP_IP_BUF->ttl != UIP_ND6_HOP_LIMIT) ||
(uip_is_addr_mcast(&UIP_ND6_NS_BUF->tgtipaddr)) ||
(UIP_ICMP_BUF->icode != 0)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
/* Options processing */
nd6_opt_llao = NULL;
nd6_opt_offset = UIP_ND6_NS_LEN;
while(uip_l3_icmp_hdr_len + nd6_opt_offset < uip_len) {
#if UIP_CONF_IPV6_CHECKS
if(UIP_ND6_OPT_HDR_BUF->len == 0) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
switch (UIP_ND6_OPT_HDR_BUF->type) {
case UIP_ND6_OPT_SLLAO:
nd6_opt_llao = &uip_buf[uip_l2_l3_icmp_hdr_len + nd6_opt_offset];
#if UIP_CONF_IPV6_CHECKS
/* There must be NO option in a DAD NS */
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
} else {
#endif /*UIP_CONF_IPV6_CHECKS */
nbr = uip_ds6_nbr_lookup(&UIP_IP_BUF->srcipaddr);
if(nbr == NULL) {
uip_ds6_nbr_add(&UIP_IP_BUF->srcipaddr,
(uip_lladdr_t *)&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
0, NBR_STALE);
} else {
if(memcmp(&nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
&nbr->lladdr, UIP_LLADDR_LEN) != 0) {
memcpy(&nbr->lladdr, &nd6_opt_llao[UIP_ND6_OPT_DATA_OFFSET],
UIP_LLADDR_LEN);
nbr->state = NBR_STALE;
} else {
if(nbr->state == NBR_INCOMPLETE) {
nbr->state = NBR_STALE;
}
}
}
#if UIP_CONF_IPV6_CHECKS
}
#endif /*UIP_CONF_IPV6_CHECKS */
break;
default:
PRINTF("ND option not supported in NS");
break;
}
nd6_opt_offset += (UIP_ND6_OPT_HDR_BUF->len << 3);
}
addr = uip_ds6_addr_lookup(&UIP_ND6_NS_BUF->tgtipaddr);
if(addr != NULL) {
if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) {
/* DAD CASE */
#if UIP_CONF_IPV6_CHECKS
if(!uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
PRINTF("NS received is bad\n");
goto discard;
}
#endif /* UIP_CONF_IPV6_CHECKS */
if(addr->state != ADDR_TENTATIVE) {
uip_create_linklocal_allnodes_mcast(&UIP_IP_BUF->destipaddr);
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
flags = UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
/** \todo if I sent a NS before him, I win */
uip_ds6_dad_failed(addr);
goto discard;
}
}
#if UIP_CONF_IPV6_CHECKS
if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) {
/**
* \NOTE do we do something here? we both are using the same address.
* If we are doing dad, we could cancel it, though we should receive a
* NA in response of DAD NS we sent, hence DAD will fail anyway. If we
* were not doing DAD, it means there is a duplicate in the network!
*/
PRINTF("NS received is bad\n");
goto discard;
}
#endif /*UIP_CONF_IPV6_CHECKS */
/* Address resolution case */
if(uip_is_addr_solicited_node(&UIP_IP_BUF->destipaddr)) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &UIP_ND6_NS_BUF->tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
}
/* NUD CASE */
if(uip_ds6_addr_lookup(&UIP_IP_BUF->destipaddr) == addr) {
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
uip_ipaddr_copy(&UIP_IP_BUF->srcipaddr, &UIP_ND6_NS_BUF->tgtipaddr);
flags = UIP_ND6_NA_FLAG_SOLICITED | UIP_ND6_NA_FLAG_OVERRIDE;
goto create_na;
} else {
#if UIP_CONF_IPV6_CHECKS
PRINTF("NS received is bad\n");
goto discard;
#endif /* UIP_CONF_IPV6_CHECKS */
}
} else {
goto discard;
}
create_na:
uip_ext_len = 0;
UIP_IP_BUF->vtc = 0x60;
UIP_IP_BUF->tcflow = 0;
UIP_IP_BUF->flow = 0;
UIP_IP_BUF->len[0] = 0; /* length will not be more than 255 */
UIP_IP_BUF->len[1] = UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_IP_BUF->proto = UIP_PROTO_ICMP6;
UIP_IP_BUF->ttl = UIP_ND6_HOP_LIMIT;
UIP_ICMP_BUF->type = ICMP6_NA;
UIP_ICMP_BUF->icode = 0;
UIP_ND6_NA_BUF->flagsreserved = flags;
memcpy(&UIP_ND6_NA_BUF->tgtipaddr, &addr->ipaddr, sizeof(uip_ipaddr_t));
create_llao(&uip_buf[uip_l2_l3_icmp_hdr_len + UIP_ND6_NA_LEN],
UIP_ND6_OPT_TLLAO);
UIP_ICMP_BUF->icmpchksum = 0;
UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
uip_len =
UIP_IPH_LEN + UIP_ICMPH_LEN + UIP_ND6_NA_LEN + UIP_ND6_OPT_LLAO_LEN;
UIP_STAT(++uip_stat.nd6.sent);
PRINTF("Sending NA to");
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
PRINTF("from");
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
PRINTF("with target address");
PRINT6ADDR(&UIP_ND6_NA_BUF->tgtipaddr);
PRINTF("\n");
return;
discard:
uip_len = 0;
return;
}
