/* functions for sending */
static void _send_unicast(kernel_pid_t iface, uint8_t *dst_l2addr,
uint16_t dst_l2addr_len, ng_pktsnip_t *pkt)
{
ng_pktsnip_t *netif;
if (pkt->type == NG_NETTYPE_NETIF) {
/* great: someone already added a netif_hdr_t we assume it's wrong
* to keep it simple
* XXX: alternative would be to check if ng_netif_hdr_t::dst_l2addr_len
* is long enough and only then to throw away the header. This causes
* to much overhead IMHO */
DEBUG("ipv6: removed old interface header\n");
pkt = ng_pktbuf_remove_snip(pkt, pkt);
}
DEBUG("ipv6: add to interface header to packet\n");
netif = ng_netif_hdr_build(NULL, 0, dst_l2addr, dst_l2addr_len);
if (netif == NULL) {
DEBUG("ipv6: error on interface header allocation, dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
/* add netif to front of the pkt list */
LL_PREPEND(pkt, netif);
DEBUG("ipv6: send unicast over interface %" PRIkernel_pid "\n", iface);
/* and send to interface */
_send_to_iface(iface, pkt);
}
static ng_pktsnip_t *_build_frag_pkt(ng_pktsnip_t *pkt, size_t payload_len,
size_t size)
{
ng_netif_hdr_t *hdr = pkt->data, *new_hdr;
ng_pktsnip_t *netif, *frag;
netif = ng_netif_hdr_build(ng_netif_hdr_get_src_addr(hdr), hdr->src_l2addr_len,
ng_netif_hdr_get_dst_addr(hdr), hdr->dst_l2addr_len);
if (netif == NULL) {
DEBUG("6lo frag: error allocating new link-layer header\n");
return NULL;
}
new_hdr = netif->data;
new_hdr->if_pid = hdr->if_pid;
new_hdr->flags = hdr->flags;
new_hdr->rssi = hdr->rssi;
new_hdr->lqi = hdr->lqi;
frag = ng_pktbuf_add(NULL, NULL, _min(size, payload_len),
NG_NETTYPE_SIXLOWPAN);
if (frag == NULL) {
DEBUG("6lo frag: error allocating first fragment\n");
ng_pktbuf_release(netif);
return NULL;
}
LL_PREPEND(frag, netif);
return frag;
}
void ng_icmpv6_echo_req_handle(kernel_pid_t iface, ng_ipv6_hdr_t *ipv6_hdr,
ng_icmpv6_echo_t *echo, uint16_t len)
{
uint8_t *payload = ((uint8_t *)echo) + sizeof(ng_icmpv6_echo_t);
ng_pktsnip_t *hdr, *pkt;
ng_netreg_entry_t *sendto = NULL;
if ((echo == NULL) || (len < sizeof(ng_icmpv6_echo_t))) {
DEBUG("icmpv6_echo: echo was NULL or len (%" PRIu16
") was < sizeof(ng_icmpv6_echo_t)\n", len);
return;
}
pkt = ng_icmpv6_echo_build(NG_ICMPV6_ECHO_REP, byteorder_ntohs(echo->id),
byteorder_ntohs(echo->seq), payload,
len - sizeof(ng_icmpv6_echo_t));
if (pkt == NULL) {
DEBUG("icmpv6_echo: no space left in packet buffer\n");
return;
}
if (ipv6_addr_is_multicast(&ipv6_hdr->dst)) {
hdr = ng_ipv6_hdr_build(pkt, NULL, 0, (uint8_t *)&ipv6_hdr->src,
sizeof(ipv6_addr_t));
}
else {
hdr = ng_ipv6_hdr_build(pkt, (uint8_t *)&ipv6_hdr->dst,
sizeof(ipv6_addr_t), (uint8_t *)&ipv6_hdr->src,
sizeof(ipv6_addr_t));
}
if (hdr == NULL) {
DEBUG("icmpv6_echo: no space left in packet buffer\n");
ng_pktbuf_release(pkt);
return;
}
pkt = hdr;
hdr = ng_netif_hdr_build(NULL, 0, NULL, 0);
((ng_netif_hdr_t *)hdr->data)->if_pid = iface;
LL_PREPEND(pkt, hdr);
sendto = ng_netreg_lookup(NG_NETTYPE_IPV6, NG_NETREG_DEMUX_CTX_ALL);
if (sendto == NULL) {
DEBUG("icmpv6_echo: no receivers for IPv6 packets\n");
ng_pktbuf_release(pkt);
return;
}
/* ICMPv6 is not interested anymore so `- 1` */
ng_pktbuf_hold(pkt, ng_netreg_num(NG_NETTYPE_IPV6, NG_NETREG_DEMUX_CTX_ALL) - 1);
while (sendto != NULL) {
ng_netapi_send(sendto->pid, pkt);
sendto = ng_netreg_getnext(sendto);
}
}
static void _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: 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: 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: 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: 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: 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 = { _rand(0, NG_NDP_MAX_AC_TGT_DELAY), 0 };
ng_ipv6_nc_t *nc_entry = ng_ipv6_nc_get(iface, tgt);
DEBUG("ndp: 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);
}
}
static void _send_nbr_sol(kernel_pid_t iface, ng_ipv6_addr_t *tgt,
ng_ipv6_addr_t *dst)
{
ng_pktsnip_t *hdr, *pkt = NULL;
ng_ipv6_addr_t *src = NULL;
size_t src_len = 0;
DEBUG("ndp: send neighbor solicitation (iface: %" PRIkernel_pid ", tgt: %s, ",
iface, ng_ipv6_addr_to_str(addr_str, tgt, sizeof(addr_str)));
DEBUG("dst: %s)\n", ng_ipv6_addr_to_str(addr_str, dst, sizeof(addr_str)));
/* check if there is a fitting source address to target */
if ((src = ng_ipv6_netif_find_best_src_addr(iface, tgt)) != NULL) {
uint8_t l2src[8];
uint16_t l2src_len;
src_len = sizeof(ng_ipv6_addr_t);
l2src_len = _get_l2src(l2src, sizeof(l2src), iface);
if (l2src_len > 0) {
/* add source address link-layer address option */
pkt = ng_ndp_opt_sl2a_build(l2src, l2src_len, NULL);
if (pkt == NULL) {
DEBUG("ndp: error allocating Source Link-layer address option.\n");
ng_pktbuf_release(pkt);
return;
}
}
}
hdr = ng_ndp_nbr_sol_build(tgt, pkt);
if (hdr == NULL) {
DEBUG("ndp: error allocating Neighbor solicitation.\n");
ng_pktbuf_release(pkt);
return;
}
pkt = hdr;
hdr = ng_ipv6_hdr_build(pkt, (uint8_t *)src, src_len, (uint8_t *)dst,
sizeof(ng_ipv6_addr_t));
if (hdr == NULL) {
DEBUG("ndp: 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: error allocating netif header.\n");
return;
}
((ng_netif_hdr_t *)hdr->data)->if_pid = iface;
LL_PREPEND(pkt, hdr);
ng_netapi_send(ng_ipv6_pid, pkt);
}
static void _send_multicast(kernel_pid_t iface, ng_pktsnip_t *pkt,
ng_pktsnip_t *ipv6, ng_pktsnip_t *payload,
bool prep_hdr)
{
ng_pktsnip_t *netif;
kernel_pid_t ifs[NG_NETIF_NUMOF];
size_t ifnum = 0;
if (iface == KERNEL_PID_UNDEF) {
/* get list of interfaces */
ifnum = ng_netif_get(ifs);
/* throw away packet if no one is interested */
if (ifnum == 0) {
DEBUG("ipv6: no interfaces registered, dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
}
#if NG_NETIF_NUMOF > 1
/* netif header not present: send over all interfaces */
if (iface == KERNEL_PID_UNDEF) {
/* send packet to link layer */
ng_pktbuf_hold(pkt, ifnum - 1);
for (size_t i = 0; i < ifnum; i++) {
if (prep_hdr) {
/* need to get second write access (duplication) to fill IPv6
* header interface-local */
ipv6 = ng_pktbuf_start_write(ipv6);
if (ipv6 == NULL) {
DEBUG("ipv6: unable to get write access to IPv6 header, "
"for interface %" PRIkernel_pid "\n", ifs[i]);
ng_pktbuf_release(pkt);
return;
}
if (_fill_ipv6_hdr(ifs[i], ipv6, payload) < 0) {
/* error on filling up header */
ng_pktbuf_release(pkt);
return;
}
}
/* allocate interface header */
netif = ng_netif_hdr_build(NULL, 0, NULL, 0);
if (netif == NULL) {
DEBUG("ipv6: error on interface header allocation, "
"dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
LL_PREPEND(pkt, netif);
_send_multicast_over_iface(ifs[i], pkt, netif);
}
}
else {
/* iface != KERNEL_PID_UNDEF implies that netif header is present */
if (prep_hdr) {
if (_fill_ipv6_hdr(iface, ipv6, payload) < 0) {
/* error on filling up header */
ng_pktbuf_release(pkt);
return;
}
}
netif = pkt;
_send_multicast_over_iface(iface, pkt, netif);
}
#else /* NG_NETIF_NUMOF */
(void)ifnum; /* not used in this build branch */
if (iface == KERNEL_PID_UNDEF) {
iface = ifs[0];
/* allocate interface header */
netif = ng_netif_hdr_build(NULL, 0, NULL, 0);
if (netif == NULL) {
DEBUG("ipv6: error on interface header allocation, "
"dropping packet\n");
ng_pktbuf_release(pkt);
return;
}
LL_PREPEND(pkt, netif);
}
else {
netif = pkt;
}
if (prep_hdr) {
if (_fill_ipv6_hdr(iface, ipv6, payload) < 0) {
/* error on filling up header */
ng_pktbuf_release(pkt);
return;
}
}
_send_multicast_over_iface(iface, pkt, netif);
#endif /* NG_NETIF_NUMOF */
}
void rbuf_add(ng_netif_hdr_t *netif_hdr, ng_pktsnip_t *pkt,
size_t frag_size, size_t offset)
{
rbuf_t *entry;
/* cppcheck is clearly wrong here */
/* cppcheck-suppress variableScope */
unsigned int data_offset = 0;
ng_sixlowpan_frag_t *frag = pkt->data;
rbuf_int_t *ptr;
uint8_t *data = ((uint8_t *)pkt->data) + sizeof(ng_sixlowpan_frag_t);
_rbuf_gc();
entry = _rbuf_get(ng_netif_hdr_get_src_addr(netif_hdr), netif_hdr->src_l2addr_len,
ng_netif_hdr_get_dst_addr(netif_hdr), netif_hdr->dst_l2addr_len,
byteorder_ntohs(frag->disp_size) & NG_SIXLOWPAN_FRAG_SIZE_MASK,
byteorder_ntohs(frag->tag));
if (entry == NULL) {
DEBUG("6lo rbuf: reassembly buffer full.\n");
return;
}
ptr = entry->ints;
/* dispatches in the first fragment are ignored */
if (offset == 0) {
if (data[0] == NG_SIXLOWPAN_UNCOMPRESSED) {
data++; /* skip 6LoWPAN dispatch */
frag_size--;
}
#ifdef MODULE_NG_SIXLOWPAN_IPHC
else if (ng_sixlowpan_iphc_is(data)) {
size_t iphc_len;
iphc_len = ng_sixlowpan_iphc_decode(entry->pkt, pkt,
sizeof(ng_sixlowpan_frag_t));
if (iphc_len == 0) {
DEBUG("6lo rfrag: could not decode IPHC dispatch\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
data += iphc_len; /* take remaining data as data */
frag_size -= iphc_len; /* and reduce frag size by IPHC dispatch length */
frag_size += sizeof(ipv6_hdr_t); /* but add IPv6 header length */
data_offset += sizeof(ipv6_hdr_t); /* start copying after IPv6 header */
}
#endif
}
else {
data++; /* FRAGN header is one byte longer (offset) */
}
if ((offset + frag_size) > entry->pkt->size) {
DEBUG("6lo rfrag: fragment too big for resulting datagram, discarding datagram\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
while (ptr != NULL) {
if (_rbuf_int_in(ptr, offset, offset + frag_size - 1)) {
DEBUG("6lo rfrag: overlapping or same intervals, discarding datagram\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
ptr = ptr->next;
}
if (_rbuf_update_ints(entry, offset, frag_size)) {
DEBUG("6lo rbuf: add fragment data\n");
entry->cur_size += (uint16_t)frag_size;
memcpy(((uint8_t *)entry->pkt->data) + offset + data_offset, data,
frag_size - data_offset);
}
if (entry->cur_size == entry->pkt->size) {
kernel_pid_t iface = netif_hdr->if_pid;
ng_pktsnip_t *netif = ng_netif_hdr_build(entry->src, entry->src_len,
entry->dst, entry->dst_len);
if (netif == NULL) {
DEBUG("6lo rbuf: error allocating netif header\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
netif_hdr = netif->data;
netif_hdr->if_pid = iface;
LL_APPEND(entry->pkt, netif);
if (!ng_netapi_dispatch_receive(NG_NETTYPE_IPV6, NG_NETREG_DEMUX_CTX_ALL,
entry->pkt)) {
DEBUG("6lo rbuf: No receivers for this packet found\n");
ng_pktbuf_release(entry->pkt);
}
_rbuf_rem(entry);
}
}
void rbuf_add(ng_netif_hdr_t *netif_hdr, ng_sixlowpan_frag_t *frag,
size_t frag_size, size_t offset)
{
rbuf_t *entry;
rbuf_int_t *ptr;
uint8_t *data = ((uint8_t *)frag) + sizeof(ng_sixlowpan_frag_t);
uint16_t dg_frag_size = frag_size; /* may differ on first fragment */
_rbuf_gc();
entry = _rbuf_get(ng_netif_hdr_get_src_addr(netif_hdr), netif_hdr->src_l2addr_len,
ng_netif_hdr_get_dst_addr(netif_hdr), netif_hdr->dst_l2addr_len,
byteorder_ntohs(frag->disp_size) & NG_SIXLOWPAN_FRAG_SIZE_MASK,
byteorder_ntohs(frag->tag));
if (entry == NULL) {
DEBUG("6lo rbuf: reassembly buffer full.\n");
return;
}
ptr = entry->ints;
/* dispatches in the first fragment are ignored */
if (offset != 0) {
switch (((uint8_t *)(entry->pkt->data))[0]) {
case NG_SIXLOWPAN_UNCOMPRESSED:
offset++;
break;
default:
break;
}
data++; /* also don't take offset field */
}
else {
switch (data[0]) {
case NG_SIXLOWPAN_UNCOMPRESSED:
dg_frag_size--;
break;
default:
break;
}
}
if ((offset + frag_size) > entry->pkt->size) {
DEBUG("6lo rfrag: fragment too big for resulting datagram, discarding datagram\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
while (ptr != NULL) {
if (_rbuf_int_in(ptr, offset, offset + dg_frag_size - 1)) {
DEBUG("6lo rfrag: overlapping or same intervals, discarding datagram\n");
ng_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
ptr = ptr->next;
}
if (_rbuf_update_ints(entry, offset, dg_frag_size)) {
if (dg_frag_size < frag_size) {
/* some dispatches do not count to datagram size and we need
* more space because of that */
if (ng_pktbuf_realloc_data(entry->pkt, entry->pkt->size +
(frag_size - dg_frag_size)) < 0) {
DEBUG("6lo rbuf: could not reallocate packet data.\n");
return;
}
/* move already inserted fragments (frag_size - dg_frag_size) to the right */
if (entry->cur_size > 0) {
for (int i = entry->pkt->size - (frag_size - dg_frag_size); i > 0; i--) {
uint8_t *d = ((uint8_t *)(entry->pkt->data)) + i;
*d = *(d - 1);
}
}
}
DEBUG("6lo rbuf: add fragment data\n");
entry->cur_size += (uint16_t)dg_frag_size;
memcpy(((uint8_t *)entry->pkt->data) + offset, data, frag_size);
}
if (entry->cur_size == entry->datagram_size) {
kernel_pid_t iface = netif_hdr->if_pid;
ng_pktsnip_t *netif = ng_netif_hdr_build(entry->src, entry->src_len,
entry->dst, entry->dst_len);
if (netif == NULL) {
DEBUG("6lo rbuf: error allocating netif header\n");
ng_pktbuf_release(entry->pkt);
return;
}
netif_hdr = netif->data;
netif_hdr->if_pid = iface;
LL_APPEND(entry->pkt, netif);
DEBUG("6lo rbuf: datagram complete, send to self\n");
ng_netapi_receive(thread_getpid(), entry->pkt);
_rbuf_rem(entry);
}
}
