static void test_ipv6_addr_is_loopback_loopback(void)
{
ng_ipv6_addr_t a = NG_IPV6_ADDR_LOOPBACK;
TEST_ASSERT_EQUAL_INT(0, a.u64[0].u64); /* Don't trust the macro ;) */
TEST_ASSERT_EQUAL_INT(1, byteorder_ntohll(a.u64[1]));
TEST_ASSERT_EQUAL_INT(true, ng_ipv6_addr_is_loopback(&a));
}
static void test_ipv6_addr_is_loopback_not_loopback(void)
{
ng_ipv6_addr_t a = { {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
}
};
TEST_ASSERT_EQUAL_INT(false, ng_ipv6_addr_is_loopback(&a));
}
/* functions for receiving */
static inline bool _pkt_not_for_me(kernel_pid_t *iface, ng_ipv6_hdr_t *hdr)
{
if (ng_ipv6_addr_is_loopback(&hdr->dst)) {
return false;
}
else if (*iface == KERNEL_PID_UNDEF) {
*iface = ng_ipv6_netif_find_by_addr(NULL, &hdr->dst);
return (*iface == KERNEL_PID_UNDEF);
}
else {
return (ng_ipv6_netif_find_addr(*iface, &hdr->dst) == NULL);
}
}
static void _send(ng_pktsnip_t *pkt, bool prep_hdr)
{
kernel_pid_t iface = KERNEL_PID_UNDEF;
ng_pktsnip_t *ipv6, *payload;
ng_ipv6_addr_t *tmp;
ng_ipv6_hdr_t *hdr;
/* get IPv6 snip and (if present) generic interface header */
if (pkt->type == NG_NETTYPE_NETIF) {
/* If there is already a netif header (routing protocols and
* neighbor discovery might add them to preset sending interface) */
iface = ((ng_netif_hdr_t *)pkt->data)->if_pid;
/* seize payload as temporary variable */
ipv6 = ng_pktbuf_start_write(pkt); /* write protect for later removal
* in _send_unicast() */
if (ipv6 == NULL) {
DEBUG("ipv6: unable to get write access to netif header, dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
pkt = ipv6; /* Reset pkt from temporary variable */
ipv6 = pkt->next;
}
else {
ipv6 = pkt;
}
/* seize payload as temporary variable */
payload = ng_pktbuf_start_write(ipv6);
if (payload == NULL) {
DEBUG("ipv6: unable to get write access to IPv6 header, dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
if (ipv6 != pkt) { /* in case packet has netif header */
pkt->next = payload;/* pkt is already write-protected so we can do that */
}
ipv6 = payload; /* Reset ipv6 from temporary variable */
hdr = ipv6->data;
payload = ipv6->next;
if (ng_ipv6_addr_is_multicast(&hdr->dst)) {
_send_multicast(iface, pkt, ipv6, payload, prep_hdr);
}
else if ((ng_ipv6_addr_is_loopback(&hdr->dst)) || /* dst is loopback address */
((iface == KERNEL_PID_UNDEF) && /* or dst registered to any local interface */
((iface = ng_ipv6_netif_find_by_addr(&tmp, &hdr->dst)) != KERNEL_PID_UNDEF)) ||
((iface != KERNEL_PID_UNDEF) && /* or dst registered to given interface */
(ng_ipv6_netif_find_addr(iface, &hdr->dst) != NULL))) {
uint8_t *rcv_data;
ng_pktsnip_t *ptr = ipv6, *rcv_pkt;
if (prep_hdr) {
if (_fill_ipv6_hdr(iface, ipv6, payload) < 0) {
/* error on filling up header */
ng_pktbuf_release(pkt);
return;
}
}
rcv_pkt = ng_pktbuf_add(NULL, NULL, ng_pkt_len(ipv6), NG_NETTYPE_IPV6);
if (rcv_pkt == NULL) {
DEBUG("ipv6: error on generating loopback packet\n");
ng_pktbuf_release(pkt);
return;
}
rcv_data = rcv_pkt->data;
/* "reverse" packet (by making it one snip as if received from NIC) */
while (ptr != NULL) {
memcpy(rcv_data, ptr->data, ptr->size);
rcv_data += ptr->size;
ptr = ptr->next;
}
ng_pktbuf_release(pkt);
DEBUG("ipv6: packet is addressed to myself => loopback\n");
ng_netapi_receive(ng_ipv6_pid, rcv_pkt);
}
else {
uint8_t l2addr_len = NG_IPV6_NC_L2_ADDR_MAX;
uint8_t l2addr[l2addr_len];
iface = _next_hop_l2addr(l2addr, &l2addr_len, iface, &hdr->dst, pkt);
if (iface == KERNEL_PID_UNDEF) {
DEBUG("ipv6: error determining next hop's link layer address\n");
ng_pktbuf_release(pkt);
return;
}
if (prep_hdr) {
if (_fill_ipv6_hdr(iface, ipv6, payload) < 0) {
/* error on filling up header */
ng_pktbuf_release(pkt);
return;
}
}
_send_unicast(iface, l2addr, l2addr_len, pkt);
}
}
static int _fill_ipv6_hdr(kernel_pid_t iface, ng_pktsnip_t *ipv6,
ng_pktsnip_t *payload)
{
int res;
ng_ipv6_hdr_t *hdr = ipv6->data;
hdr->len = byteorder_htons(ng_pkt_len(payload));
DEBUG("ipv6: set payload length to %zu (network byteorder %04" PRIx16 ")\n",
ng_pkt_len(payload), hdr->len.u16);
/* check if e.g. extension header was not already marked */
if (hdr->nh == PROTNUM_RESERVED) {
hdr->nh = ng_nettype_to_protnum(payload->type);
/* if still reserved: mark no next header */
if (hdr->nh == PROTNUM_RESERVED) {
hdr->nh = PROTNUM_IPV6_NONXT;
}
}
DEBUG("ipv6: set next header to %" PRIu8 "\n", hdr->nh);
if (hdr->hl == 0) {
if (iface == KERNEL_PID_UNDEF) {
hdr->hl = NG_IPV6_NETIF_DEFAULT_HL;
}
else {
hdr->hl = ng_ipv6_netif_get(iface)->cur_hl;
}
}
if (ng_ipv6_addr_is_unspecified(&hdr->src)) {
if (ng_ipv6_addr_is_loopback(&hdr->dst)) {
ng_ipv6_addr_set_loopback(&hdr->src);
}
else {
ng_ipv6_addr_t *src = ng_ipv6_netif_find_best_src_addr(iface, &hdr->dst);
if (src != NULL) {
DEBUG("ipv6: set packet source to %s\n",
ng_ipv6_addr_to_str(addr_str, src, sizeof(addr_str)));
memcpy(&hdr->src, src, sizeof(ng_ipv6_addr_t));
}
/* Otherwise leave unspecified */
}
}
DEBUG("ipv6: calculate checksum for upper header.\n");
#if NG_NETIF_NUMOF > 1
if (payload->users > 1) {
ng_pktsnip_t *ptr = ipv6;
/* We deal with multiple interfaces here (multicast) => possible
* different source addresses => duplication of payload needed */
while (ptr != payload->next) {
ng_pktsnip_t *old = ptr->next;
/* duplicate everything including payload */
ptr->next = ng_pktbuf_start_write(ptr->next);
if (ptr->next == NULL) {
DEBUG("ipv6: unable to get write access to payload, drop it\n");
return -ENOBUFS;
}
ptr = old;
}
}
#endif /* NG_NETIF_NUMOF */
if ((res = ng_netreg_calc_csum(payload, ipv6)) < 0) {
if (res != -ENOENT) { /* if there is no checksum we are okay */
DEBUG("ipv6: checksum calculation failed.\n");
return res;
}
}
return 0;
}
