static uint8_t _find_by_prefix_unsafe(ipv6_addr_t **res, gnrc_ipv6_netif_t *iface,
const ipv6_addr_t *addr, uint8_t *only)
{
uint8_t best_match = 0;
for (int i = 0; i < GNRC_IPV6_NETIF_ADDR_NUMOF; i++) {
uint8_t match;
if ((only != NULL) && !(bf_isset(only, i))) {
continue;
}
if (((only != NULL) &&
gnrc_ipv6_netif_addr_is_non_unicast(&(iface->addrs[i].addr))) ||
ipv6_addr_is_unspecified(&(iface->addrs[i].addr))) {
continue;
}
match = ipv6_addr_match_prefix(&(iface->addrs[i].addr), addr);
if ((only == NULL) && !ipv6_addr_is_multicast(addr) &&
(match < iface->addrs[i].prefix_len)) {
/* match but not of same subnet */
continue;
}
if (match > best_match) {
if (res != NULL) {
*res = &(iface->addrs[i].addr);
}
best_match = match;
}
}
#if ENABLE_DEBUG
if (*res != NULL) {
DEBUG("ipv6 netif: Found %s on interface %" PRIkernel_pid " matching ",
ipv6_addr_to_str(addr_str, *res, sizeof(addr_str)),
iface->pid);
DEBUG("%s by %" PRIu8 " bits (used as source address = %s)\n",
ipv6_addr_to_str(addr_str, addr, sizeof(addr_str)),
best_match,
(only != NULL) ? "true" : "false");
}
else {
DEBUG("ipv6 netif: Did not found any address on interface %" PRIkernel_pid
" matching %s (used as source address = %s)\n",
iface->pid,
ipv6_addr_to_str(addr_str, addr, sizeof(addr_str)),
(only != NULL) ? "true" : "false");
}
#endif
return best_match;
}
static bool _pio_from_iface_addr(gnrc_pktsnip_t **res, gnrc_ipv6_netif_addr_t *addr,
gnrc_pktsnip_t *next)
{
if (((addr->prefix_len - 1U) > 127U) && /* 0 < prefix_len < 128 */
!ipv6_addr_is_unspecified(&addr->addr) &&
!ipv6_addr_is_link_local(&addr->addr) &&
!gnrc_ipv6_netif_addr_is_non_unicast(&addr->addr)) {
DEBUG(" - PIO for %s/%" PRIu8 "\n", ipv6_addr_to_str(addr_str, &addr->addr,
sizeof(addr_str)),
addr->prefix_len);
*res = gnrc_ndp_opt_pi_build(addr->prefix_len, (addr->flags &
(GNRC_IPV6_NETIF_ADDR_FLAGS_NDP_AUTO |
GNRC_IPV6_NETIF_ADDR_FLAGS_NDP_ON_LINK)),
addr->valid, addr->preferred, &addr->addr, next);
return true;
}
return false;
}
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);
}
}
}
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);
}
}
