static inline void _set_reach_time(gnrc_ipv6_netif_t *if_entry, uint32_t mean)
{
uint32_t reach_time = genrand_uint32_range(GNRC_NDP_MIN_RAND, GNRC_NDP_MAX_RAND);
if_entry->reach_time_base = mean;
/* to avoid floating point number computation and have higher value entropy, the
* boundaries for the random value are multiplied by 10 and we need to account for that */
reach_time = (reach_time * if_entry->reach_time_base) / 10;
if_entry->reach_time = reach_time;
}
void ng_ndp_netif_add(ng_ipv6_netif_t *iface)
{
uint32_t reach_time = genrand_uint32_range(NG_NDP_MIN_RAND, NG_NDP_MAX_RAND);
/* set default values */
mutex_lock(&iface->mutex);
iface->reach_time_base = NG_NDP_REACH_TIME;
reach_time = (reach_time * iface->reach_time_base) / 10;
iface->reach_time = timex_set(0, reach_time);
timex_normalize(&iface->reach_time);
iface->retrans_timer = timex_set(0, NG_NDP_RETRANS_TIMER);
timex_normalize(&iface->retrans_timer);
mutex_unlock(&iface->mutex);
}
static void _send_rtr_adv(gnrc_ipv6_netif_t *iface, ipv6_addr_t *dst)
{
bool fin;
uint32_t interval;
mutex_lock(&iface->mutex);
fin = (iface->adv_ltime == 0);
assert((iface->min_adv_int != 0) && (iface->max_adv_int != 0));
interval = genrand_uint32_range(iface->min_adv_int, iface->max_adv_int);
if (!fin && !((iface->flags | GNRC_IPV6_NETIF_FLAGS_ROUTER) &&
(iface->flags | GNRC_IPV6_NETIF_FLAGS_RTR_ADV))) {
DEBUG("ndp rtr: interface %" PRIkernel_pid " is not an advertising interface\n",
iface->pid);
return;
}
if (iface->rtr_adv_count > 1) { /* regard for off-by-one error */
iface->rtr_adv_count--;
if (!fin && (interval > GNRC_NDP_MAX_INIT_RTR_ADV_INT)) {
interval = GNRC_NDP_MAX_INIT_RTR_ADV_INT;
}
}
if (!fin || (iface->rtr_adv_count > 1)) { /* regard for off-by-one-error */
/* reset timer for next router advertisement */
xtimer_remove(&iface->rtr_adv_timer);
iface->rtr_adv_msg.type = GNRC_NDP_MSG_RTR_ADV_RETRANS;
iface->rtr_adv_msg.content.ptr = (char *) iface;
xtimer_set_msg(&iface->rtr_adv_timer, interval * SEC_IN_USEC, &iface->rtr_adv_msg,
gnrc_ipv6_pid);
}
mutex_unlock(&iface->mutex);
for (int i = 0; i < GNRC_IPV6_NETIF_ADDR_NUMOF; i++) {
ipv6_addr_t *src = &iface->addrs[i].addr;
if (!ipv6_addr_is_unspecified(src) && ipv6_addr_is_link_local(src) &&
!gnrc_ipv6_netif_addr_is_non_unicast(src)) {
/* send one for every link local address (ideally there is only one) */
gnrc_ndp_internal_send_rtr_adv(iface->pid, src, dst, fin);
}
}
}
static int _implicit_bind(socket_t *s, void *addr)
{
ipv6_addr_t unspec;
ipv6_addr_t *best_match;
int res;
/* TODO: ensure that this port hasn't been used yet */
s->src_port = (uint16_t)genrand_uint32_range(1LU << 10U, 1LU << 16U);
/* find the best matching source address */
if ((best_match = conn_find_best_source(addr)) == NULL) {
ipv6_addr_set_unspecified(&unspec);
best_match = &unspec;
}
switch (s->type) {
#ifdef MODULE_CONN_TCP
case SOCK_STREAM:
res = conn_tcp_create(&s->conn.udp, best_match, sizeof(unspec),
s->domain, s->src_port);
break;
#endif
#ifdef MODULE_CONN_UDP
case SOCK_DGRAM:
res = conn_udp_create(&s->conn.udp, best_match, sizeof(unspec),
s->domain, s->src_port);
break;
#endif
default:
res = -1;
break;
}
if (res < 0) {
errno = -res;
}
else {
s->bound = true;
}
return res;
}
void gnrc_ndp_internal_send_nbr_adv(kernel_pid_t iface, ipv6_addr_t *tgt, ipv6_addr_t *dst,
bool supply_tl2a, gnrc_pktsnip_t *ext_opts)
{
gnrc_pktsnip_t *hdr, *pkt = ext_opts;
uint8_t adv_flags = 0;
DEBUG("ndp internal: send neighbor advertisement (iface: %" PRIkernel_pid ", tgt: %s, ",
iface, ipv6_addr_to_str(addr_str, tgt, sizeof(addr_str)));
DEBUG("dst: %s, supply_tl2a: %d)\n",
ipv6_addr_to_str(addr_str, dst, sizeof(addr_str)), supply_tl2a);
if ((gnrc_ipv6_netif_get(iface)->flags & GNRC_IPV6_NETIF_FLAGS_ROUTER) &&
(gnrc_ipv6_netif_get(iface)->flags & GNRC_IPV6_NETIF_FLAGS_RTR_ADV)) {
adv_flags |= NDP_NBR_ADV_FLAGS_R;
}
if (ipv6_addr_is_unspecified(dst)) {
ipv6_addr_set_all_nodes_multicast(dst, IPV6_ADDR_MCAST_SCP_LINK_LOCAL);
}
else {
adv_flags |= NDP_NBR_ADV_FLAGS_S;
}
if (supply_tl2a) {
uint8_t l2src[8];
size_t l2src_len;
/* we previously checked if we are the target, so we can take our L2src */
l2src_len = _get_l2src(iface, l2src, sizeof(l2src));
if (l2src_len > 0) {
/* add target address link-layer address option */
pkt = gnrc_ndp_opt_tl2a_build(l2src, l2src_len, pkt);
if (pkt == NULL) {
DEBUG("ndp internal: error allocating Target Link-layer address option.\n");
gnrc_pktbuf_release(ext_opts);
return;
}
}
}
/* TODO: also check if the node provides proxy servies for tgt */
if ((pkt != NULL) && !gnrc_ipv6_netif_addr_is_non_unicast(tgt)) {
/* TL2A is not supplied and tgt is not anycast */
adv_flags |= NDP_NBR_ADV_FLAGS_O;
}
hdr = gnrc_ndp_nbr_adv_build(adv_flags, tgt, pkt);
if (hdr == NULL) {
DEBUG("ndp internal: error allocating Neighbor advertisement.\n");
gnrc_pktbuf_release(pkt);
return;
}
pkt = hdr;
hdr = _build_headers(iface, pkt, dst, NULL);
if (hdr == NULL) {
DEBUG("ndp internal: error adding lower-layer headers.\n");
gnrc_pktbuf_release(pkt);
return;
}
if (gnrc_ipv6_netif_addr_is_non_unicast(tgt)) {
/* avoid collision for anycast addresses
* (see https://tools.ietf.org/html/rfc4861#section-7.2.7) */
uint32_t delay = genrand_uint32_range(0, GNRC_NDP_MAX_AC_TGT_DELAY * SEC_IN_USEC);
gnrc_ipv6_nc_t *nc_entry = gnrc_ipv6_nc_get(iface, dst);
DEBUG("ndp internal: delay neighbor advertisement for %" PRIu32 " sec.",
(delay / SEC_IN_USEC));
/* nc_entry must be set so no need to check it */
assert(nc_entry);
_send_delayed(&nc_entry->nbr_adv_timer, &nc_entry->nbr_adv_msg, delay, hdr);
}
else if (gnrc_netapi_send(gnrc_ipv6_pid, hdr) < 1) {
DEBUG("ndp internal: unable to send neighbor advertisement\n");
gnrc_pktbuf_release(hdr);
}
}
static inline uint32_t _binary_exp_backoff(uint32_t base_sec, unsigned int exp)
{
return genrand_uint32_range(0, (1 << exp)) * base_sec;
}
void gnrc_ndp_rtr_sol_handle(kernel_pid_t iface, gnrc_pktsnip_t *pkt,
ipv6_hdr_t *ipv6, ndp_rtr_sol_t *rtr_sol,
size_t icmpv6_size)
{
gnrc_ipv6_netif_t *if_entry = gnrc_ipv6_netif_get(iface);
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_ROUTER) {
int sicmpv6_size = (int)icmpv6_size, l2src_len = 0;
uint8_t l2src[GNRC_IPV6_NC_L2_ADDR_MAX];
uint16_t opt_offset = 0;
uint8_t *buf = (uint8_t *)(rtr_sol + 1);
/* check validity */
if ((ipv6->hl != 255) || (rtr_sol->code != 0) ||
(icmpv6_size < sizeof(ndp_rtr_sol_t))) {
DEBUG("ndp: router solicitation was invalid\n");
return;
}
sicmpv6_size -= sizeof(ndp_rtr_sol_t);
while (sicmpv6_size > 0) {
ndp_opt_t *opt = (ndp_opt_t *)(buf + opt_offset);
switch (opt->type) {
case NDP_OPT_SL2A:
if ((l2src_len = gnrc_ndp_internal_sl2a_opt_handle(pkt, ipv6, rtr_sol->type, opt,
l2src)) < 0) {
/* -ENOTSUP can not happen */
/* invalid source link-layer address option */
return;
}
break;
default:
/* silently discard all other options */
break;
}
opt_offset += (opt->len * 8);
sicmpv6_size -= (opt->len * 8);
#if ENABLE_DEBUG
if (sicmpv6_size < 0) {
DEBUG("ndp: Option parsing out of sync.\n");
}
#endif
}
_stale_nc(iface, &ipv6->src, l2src, l2src_len);
/* send delayed */
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_RTR_ADV) {
uint32_t delay;
uint32_t ms = GNRC_NDP_MAX_RTR_ADV_DELAY;
#ifdef MODULE_GNRC_SIXLOWPAN_ND_ROUTER
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_SIXLOWPAN) {
ms = GNRC_SIXLOWPAN_ND_MAX_RTR_ADV_DELAY;
}
#endif
delay = genrand_uint32_range(0, ms);
xtimer_remove(&if_entry->rtr_adv_timer);
#ifdef MODULE_GNRC_SIXLOWPAN_ND_ROUTER
/* in case of a 6LBR we have to check if the interface is actually
* the 6lo interface */
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_SIXLOWPAN) {
gnrc_ipv6_nc_t *nc_entry = gnrc_ipv6_nc_get(iface, &ipv6->src);
if (nc_entry != NULL) {
if_entry->rtr_adv_msg.type = GNRC_NDP_MSG_RTR_ADV_SIXLOWPAN_DELAY;
if_entry->rtr_adv_msg.content.ptr = (char *) nc_entry;
xtimer_set_msg(&if_entry->rtr_adv_timer, delay, &if_entry->rtr_adv_msg,
gnrc_ipv6_pid);
}
}
#elif defined(MODULE_GNRC_NDP_ROUTER) || defined(MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER)
if (ipv6_addr_is_unspecified(&ipv6->src)) {
/* either multicast, if source unspecified */
if_entry->rtr_adv_msg.type = GNRC_NDP_MSG_RTR_ADV_RETRANS;
if_entry->rtr_adv_msg.content.ptr = (char *) if_entry;
xtimer_set_msg(&if_entry->rtr_adv_timer, delay, &if_entry->rtr_adv_msg,
gnrc_ipv6_pid);
}
else {
/* or unicast, if source is known */
/* XXX: can't just use GNRC_NETAPI_MSG_TYPE_SND, since the next retransmission
* must also be set. */
gnrc_ipv6_nc_t *nc_entry = gnrc_ipv6_nc_get(iface, &ipv6->src);
xtimer_set_msg(&nc_entry->rtr_adv_timer, delay, &nc_entry->rtr_adv_msg,
gnrc_ipv6_pid);
}
#endif
}
}
/* otherwise ignore silently */
}
void gnrc_ndp_rtr_sol_handle(kernel_pid_t iface, gnrc_pktsnip_t *pkt,
ipv6_hdr_t *ipv6, ndp_rtr_sol_t *rtr_sol,
size_t icmpv6_size)
{
gnrc_ipv6_netif_t *if_entry = gnrc_ipv6_netif_get(iface);
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_ROUTER) {
int sicmpv6_size = (int)icmpv6_size, l2src_len = 0;
uint8_t l2src[GNRC_IPV6_NC_L2_ADDR_MAX];
uint16_t opt_offset = 0;
uint8_t *buf = (uint8_t *)(rtr_sol + 1);
/* check validity */
if ((ipv6->hl != 255) || (rtr_sol->code != 0) ||
(icmpv6_size < sizeof(ndp_rtr_sol_t))) {
DEBUG("ndp: router solicitation was invalid\n");
return;
}
sicmpv6_size -= sizeof(ndp_rtr_sol_t);
while (sicmpv6_size > 0) {
ndp_opt_t *opt = (ndp_opt_t *)(buf + opt_offset);
switch (opt->type) {
case NDP_OPT_SL2A:
if ((l2src_len = gnrc_ndp_internal_sl2a_opt_handle(pkt, ipv6, rtr_sol->type, opt,
l2src)) < 0) {
/* -ENOTSUP can not happen */
/* invalid source link-layer address option */
return;
}
break;
default:
/* silently discard all other options */
break;
}
opt_offset += (opt->len * 8);
sicmpv6_size -= (opt->len * 8);
}
_stale_nc(iface, &ipv6->src, l2src, l2src_len);
/* send delayed */
if (if_entry->flags & GNRC_IPV6_NETIF_FLAGS_RTR_ADV) {
timex_t delay = timex_set(0, genrand_uint32_range(0, GNRC_NDP_MAX_RTR_ADV_DELAY));
vtimer_remove(&if_entry->rtr_adv_timer);
if (ipv6_addr_is_unspecified(&ipv6->src)) {
/* either multicast, if source unspecified */
vtimer_set_msg(&if_entry->rtr_adv_timer, delay, gnrc_ipv6_pid,
GNRC_NDP_MSG_RTR_ADV_RETRANS, if_entry);
}
else {
/* or unicast, if source is known */
/* XXX: can't just use GNRC_NETAPI_MSG_TYPE_SND, since the next retransmission
* must also be set. */
gnrc_ipv6_nc_t *nc_entry = gnrc_ipv6_nc_get(iface, &ipv6->src);
vtimer_set_msg(&if_entry->rtr_adv_timer, delay, gnrc_ipv6_pid,
GNRC_NDP_MSG_RTR_ADV_DELAY, nc_entry);
}
}
}
/* otherwise ignore silently */
}
void ng_ndp_internal_send_nbr_adv(kernel_pid_t iface, ng_ipv6_addr_t *tgt,
ng_ipv6_addr_t *dst, bool supply_tl2a)
{
ng_pktsnip_t *hdr, *pkt = NULL;
uint8_t adv_flags = 0;
DEBUG("ndp internal: send neighbor advertisement (iface: %" PRIkernel_pid ", tgt: %s, ",
iface, ng_ipv6_addr_to_str(addr_str, tgt, sizeof(addr_str)));
DEBUG("dst: %s, supply_tl2a: %d)\n",
ng_ipv6_addr_to_str(addr_str, dst, sizeof(addr_str)), supply_tl2a);
if (ng_ipv6_netif_get(iface)->flags & NG_IPV6_NETIF_FLAGS_ROUTER) {
adv_flags |= NG_NDP_NBR_ADV_FLAGS_R;
}
if (ng_ipv6_addr_is_unspecified(dst)) {
ng_ipv6_addr_set_all_nodes_multicast(dst,
NG_IPV6_ADDR_MCAST_SCP_LINK_LOCAL);
}
else {
adv_flags |= NG_NDP_NBR_ADV_FLAGS_S;
}
if (supply_tl2a) {
uint8_t l2src[8];
uint16_t l2src_len;
/* we previously checked if we are the target, so we can take our L2src */
l2src_len = _get_l2src(l2src, sizeof(l2src), iface);
if (l2src_len > 0) {
/* add target address link-layer address option */
pkt = ng_ndp_opt_tl2a_build(l2src, l2src_len, NULL);
if (pkt == NULL) {
DEBUG("ndp internal: error allocating Target Link-layer address option.\n");
ng_pktbuf_release(pkt);
return;
}
}
}
/* TODO: also check if the node provides proxy servies for tgt */
if ((pkt != NULL) && !ng_ipv6_netif_addr_is_non_unicast(tgt)) {
/* TL2A is not supplied and tgt is not anycast */
adv_flags |= NG_NDP_NBR_ADV_FLAGS_O;
}
hdr = ng_ndp_nbr_adv_build(adv_flags, tgt, pkt);
if (hdr == NULL) {
DEBUG("ndp internal: error allocating Neighbor advertisement.\n");
ng_pktbuf_release(pkt);
return;
}
pkt = hdr;
hdr = ng_ipv6_hdr_build(pkt, NULL, 0, (uint8_t *)dst,
sizeof(ng_ipv6_addr_t));
if (hdr == NULL) {
DEBUG("ndp internal: error allocating IPv6 header.\n");
ng_pktbuf_release(pkt);
return;
}
((ng_ipv6_hdr_t *)hdr->data)->hl = 255;
pkt = hdr;
/* add netif header for send interface specification */
hdr = ng_netif_hdr_build(NULL, 0, NULL, 0);
if (hdr == NULL) {
DEBUG("ndp internal: error allocating netif header.\n");
return;
}
((ng_netif_hdr_t *)hdr->data)->if_pid = iface;
LL_PREPEND(pkt, hdr);
if (ng_ipv6_netif_addr_is_non_unicast(tgt)) {
/* avoid collision for anycast addresses
* (see https://tools.ietf.org/html/rfc4861#section-7.2.7) */
timex_t delay = { 0, genrand_uint32_range(0, NG_NDP_MAX_AC_TGT_DELAY * SEC_IN_USEC) };
timex_normalize(&delay);
ng_ipv6_nc_t *nc_entry = ng_ipv6_nc_get(iface, tgt);
DEBUG("ndp internal: delay neighbor advertisement for %" PRIu32 " sec.",
delay.seconds);
/* nc_entry must be set so no need to check it */
_send_delayed(&nc_entry->nbr_adv_timer, delay, pkt);
}
else {
ng_netapi_send(ng_ipv6_pid, pkt);
}
}
