static inline kernel_pid_t _next_hop_l2addr(uint8_t *l2addr, uint8_t *l2addr_len,
kernel_pid_t iface, ipv6_addr_t *dst,
gnrc_pktsnip_t *pkt)
{
kernel_pid_t found_iface;
#if defined(MODULE_GNRC_SIXLOWPAN_ND)
(void)pkt;
found_iface = gnrc_sixlowpan_nd_next_hop_l2addr(l2addr, l2addr_len, iface, dst);
if (found_iface > KERNEL_PID_UNDEF) {
return found_iface;
}
#endif
#if defined(MODULE_GNRC_NDP_NODE)
found_iface = gnrc_ndp_node_next_hop_l2addr(l2addr, l2addr_len, iface, dst, pkt);
#elif !defined(MODULE_GNRC_SIXLOWPAN_ND) && defined(MODULE_GNRC_IPV6_NC)
(void)pkt;
gnrc_ipv6_nc_t *nc = gnrc_ipv6_nc_get(iface, dst);
found_iface = gnrc_ipv6_nc_get_l2_addr(l2addr, l2addr_len, nc);
#elif !defined(MODULE_GNRC_SIXLOWPAN_ND)
found_iface = KERNEL_PID_UNDEF;
(void)l2addr;
(void)l2addr_len;
(void)iface;
(void)dst;
(void)pkt;
*l2addr_len = 0;
#endif
return found_iface;
}
static void test_ipv6_nc_get_l2_addr__NULL_entry(void)
{
gnrc_ipv6_nc_t *entry = NULL;
uint8_t l2_addr[GNRC_IPV6_NC_L2_ADDR_MAX];
uint8_t l2_addr_len = 0;
TEST_ASSERT_EQUAL_INT(KERNEL_PID_UNDEF,
gnrc_ipv6_nc_get_l2_addr(l2_addr, &l2_addr_len, entry));
}
static void test_ipv6_nc_get_l2_addr__unreachable(void)
{
ipv6_addr_t addr = DEFAULT_TEST_IPV6_ADDR;
gnrc_ipv6_nc_t *entry = NULL;
uint8_t l2_addr[GNRC_IPV6_NC_L2_ADDR_MAX];
uint8_t l2_addr_len = 0;
test_ipv6_nc_add__success(); /* adds DEFAULT_TEST_IPV6_ADDR to DEFAULT_TEST_NETIF */
TEST_ASSERT_NOT_NULL((entry = gnrc_ipv6_nc_get(KERNEL_PID_UNDEF, &addr)));
entry->flags = (GNRC_IPV6_NC_STATE_INCOMPLETE << GNRC_IPV6_NC_STATE_POS);
TEST_ASSERT_EQUAL_INT(KERNEL_PID_UNDEF,
gnrc_ipv6_nc_get_l2_addr(l2_addr, &l2_addr_len, entry));
}
kernel_pid_t gnrc_sixlowpan_nd_next_hop_l2addr(uint8_t *l2addr, uint8_t *l2addr_len,
kernel_pid_t iface, ipv6_addr_t *dst)
{
ipv6_addr_t *next_hop = NULL;
gnrc_ipv6_nc_t *nc_entry = NULL;
#ifdef MODULE_FIB
kernel_pid_t fib_iface;
ipv6_addr_t next_hop_actual; /* FIB copies address into this variable */
/* don't look-up link local addresses in FIB */
if ((next_hop == NULL) && !ipv6_addr_is_link_local(dst)) {
size_t next_hop_size = sizeof(ipv6_addr_t);
uint32_t next_hop_flags = 0;
if ((next_hop == NULL) &&
(fib_get_next_hop(&gnrc_ipv6_fib_table, &fib_iface, next_hop_actual.u8, &next_hop_size,
&next_hop_flags, (uint8_t *)dst,
sizeof(ipv6_addr_t), 0) >= 0) &&
(next_hop_size == sizeof(ipv6_addr_t))) {
next_hop = &next_hop_actual;
}
}
#endif
#ifdef MODULE_GNRC_SIXLOWPAN_ND_ROUTER
/* next hop determination: https://tools.ietf.org/html/rfc6775#section-6.5.4 */
nc_entry = gnrc_ipv6_nc_get(iface, dst);
#ifdef MODULE_FIB
if ((next_hop != NULL) && (nc_entry == NULL)) {
nc_entry = gnrc_ipv6_nc_get(fib_iface, dst);
}
#endif
/* if NCE found */
if (nc_entry != NULL) {
gnrc_ipv6_netif_t *ipv6_if = gnrc_ipv6_netif_get(nc_entry->iface);
/* and interface is not 6LoWPAN */
if (!((ipv6_if == NULL) ||
(ipv6_if->flags & GNRC_IPV6_NETIF_FLAGS_SIXLOWPAN)) ||
/* or entry is registered */
(gnrc_ipv6_nc_get_type(nc_entry) == GNRC_IPV6_NC_TYPE_REGISTERED)) {
next_hop = dst;
}
}
#endif
/* next hop determination according to: https://tools.ietf.org/html/rfc6775#section-5.6 */
if ((next_hop == NULL) && ipv6_addr_is_link_local(dst)) { /* prefix is "on-link" */
/* multicast is not handled here anyway so we don't need to check that */
next_hop = dst;
}
else if (next_hop == NULL) { /* prefix is off-link */
next_hop = gnrc_ndp_internal_default_router();
}
/* no routers found */
if (next_hop == NULL) {
return KERNEL_PID_UNDEF;
}
/* address resolution of next_hop: https://tools.ietf.org/html/rfc6775#section-5.7 */
if ((nc_entry == NULL) || (next_hop != dst)) {
/* get if not gotten from previous check */
nc_entry = gnrc_ipv6_nc_get(iface, next_hop);
}
/* If a (non-tentative) NCE for this destination exist, we can use even for
* link-local addresses. This should be only the case for 6LBRs. */
if ((ipv6_addr_is_link_local(next_hop)) &&
((nc_entry == NULL) ||
(gnrc_ipv6_nc_get_type(nc_entry) == GNRC_IPV6_NC_TYPE_TENTATIVE))) {
/* in case of a border router there is no sensible way for address resolution
* if the interface is not given */
#ifdef MODULE_GNRC_SIXLOWPAN_ND_BORDER_ROUTER
/* if no interface is specified it is impossible to resolve the
* link-layer address for a link-local address on a 6LBR */
if (iface == KERNEL_PID_UNDEF) {
return KERNEL_PID_UNDEF;
}
#endif
kernel_pid_t ifs[GNRC_NETIF_NUMOF];
size_t ifnum = gnrc_netif_get(ifs);
/* we don't need address resolution, the EUI-64 is in next_hop's IID */
*l2addr_len = sizeof(eui64_t);
memcpy(l2addr, &next_hop->u8[8], sizeof(eui64_t));
_revert_iid(l2addr);
if (iface == KERNEL_PID_UNDEF) {
for (unsigned i = 0; i < ifnum; i++) {
gnrc_ipv6_netif_t *ipv6_if = gnrc_ipv6_netif_get(ifs[i]);
if ((ipv6_if != NULL) && (ipv6_if->flags & GNRC_IPV6_NETIF_FLAGS_SIXLOWPAN)) {
/* always take the first 6LoWPAN interface we can find */
return ifs[i];
}
}
}
return iface;
}
if ((gnrc_ipv6_nc_get_type(nc_entry) == GNRC_IPV6_NC_TYPE_TENTATIVE)) {
return KERNEL_PID_UNDEF;
}
else {
if (gnrc_ipv6_nc_get_state(nc_entry) == GNRC_IPV6_NC_STATE_STALE) {
gnrc_ndp_internal_set_state(nc_entry, GNRC_IPV6_NC_STATE_DELAY);
}
}
return gnrc_ipv6_nc_get_l2_addr(l2addr, l2addr_len, nc_entry);
}
