void rbuf_add(gnrc_netif_hdr_t *netif_hdr, gnrc_pktsnip_t *pkt,
size_t frag_size, size_t offset)
{
rbuf_t *entry;
/* cppcheck-suppress variableScope
* (reason: cppcheck is clearly wrong here) */
unsigned int data_offset = 0;
size_t original_size = frag_size;
sixlowpan_frag_t *frag = pkt->data;
rbuf_int_t *ptr;
uint8_t *data = ((uint8_t *)pkt->data) + sizeof(sixlowpan_frag_t);
_rbuf_gc();
entry = _rbuf_get(gnrc_netif_hdr_get_src_addr(netif_hdr), netif_hdr->src_l2addr_len,
gnrc_netif_hdr_get_dst_addr(netif_hdr), netif_hdr->dst_l2addr_len,
byteorder_ntohs(frag->disp_size) & 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] == SIXLOWPAN_UNCOMP) {
data++; /* skip 6LoWPAN dispatch */
frag_size--;
}
#ifdef MODULE_GNRC_SIXLOWPAN_IPHC
else if (sixlowpan_iphc_is(data)) {
size_t iphc_len, nh_len = 0;
iphc_len = gnrc_sixlowpan_iphc_decode(&entry->pkt, pkt, entry->pkt->size,
sizeof(sixlowpan_frag_t), &nh_len);
if (iphc_len == 0) {
DEBUG("6lo rfrag: could not decode IPHC dispatch\n");
gnrc_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 */
/* but add IPv6 header + next header lengths */
frag_size += sizeof(ipv6_hdr_t) + nh_len;
/* start copying after IPv6 header and next headers */
data_offset += sizeof(ipv6_hdr_t) + nh_len;
}
#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");
gnrc_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
/* If the fragment overlaps another fragment and differs in either the size
* or the offset of the overlapped fragment, discards the datagram
* https://tools.ietf.org/html/rfc4944#section-5.3 */
while (ptr != NULL) {
if (_rbuf_int_overlap_partially(ptr, offset, offset + frag_size - 1)) {
DEBUG("6lo rfrag: overlapping intervals, discarding datagram\n");
gnrc_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
/* "A fresh reassembly may be commenced with the most recently
* received link fragment"
* https://tools.ietf.org/html/rfc4944#section-5.3 */
rbuf_add(netif_hdr, pkt, original_size, offset);
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) {
gnrc_pktsnip_t *netif = gnrc_netif_hdr_build(entry->src, entry->src_len,
entry->dst, entry->dst_len);
if (netif == NULL) {
DEBUG("6lo rbuf: error allocating netif header\n");
gnrc_pktbuf_release(entry->pkt);
_rbuf_rem(entry);
return;
}
/* copy the transmit information of the latest fragment into the newly
* created header to have some link_layer information. The link_layer
* info of the previous fragments is discarded.
*/
gnrc_netif_hdr_t *new_netif_hdr = netif->data;
new_netif_hdr->if_pid = netif_hdr->if_pid;
new_netif_hdr->flags = netif_hdr->flags;
new_netif_hdr->lqi = netif_hdr->lqi;
new_netif_hdr->rssi = netif_hdr->rssi;
LL_APPEND(entry->pkt, netif);
if (!gnrc_netapi_dispatch_receive(GNRC_NETTYPE_IPV6, GNRC_NETREG_DEMUX_CTX_ALL,
entry->pkt)) {
DEBUG("6lo rbuf: No receivers for this packet found\n");
gnrc_pktbuf_release(entry->pkt);
}
_rbuf_rem(entry);
}
}
static void _receive(ng_pktsnip_t *pkt)
{
ng_pktsnip_t *payload;
uint8_t *dispatch;
/* seize payload as a temporary variable */
payload = ng_pktbuf_start_write(pkt); /* need to duplicate since pkt->next
* might get replaced */
if (payload == NULL) {
DEBUG("6lo: can not get write access on received packet\n");
#if defined(DEVELHELP) && ENABLE_DEBUG
ng_pktbuf_stats();
#endif
ng_pktbuf_release(pkt);
return;
}
pkt = payload; /* reset pkt from temporary variable */
LL_SEARCH_SCALAR(pkt, payload, type, NG_NETTYPE_SIXLOWPAN);
if ((payload == NULL) || (payload->size < 1)) {
DEBUG("6lo: Received packet has no 6LoWPAN payload\n");
ng_pktbuf_release(pkt);
return;
}
dispatch = payload->data;
if (dispatch[0] == SIXLOWPAN_UNCOMP) {
ng_pktsnip_t *sixlowpan;
DEBUG("6lo: received uncompressed IPv6 packet\n");
payload = ng_pktbuf_start_write(payload);
if (payload == NULL) {
DEBUG("6lo: can not get write access on received packet\n");
#if defined(DEVELHELP) && ENABLE_DEBUG
ng_pktbuf_stats();
#endif
ng_pktbuf_release(pkt);
return;
}
/* packet is uncompressed: just mark and remove the dispatch */
sixlowpan = ng_pktbuf_mark(payload, sizeof(uint8_t), NG_NETTYPE_SIXLOWPAN);
if (sixlowpan == NULL) {
DEBUG("6lo: can not mark 6LoWPAN dispatch\n");
ng_pktbuf_release(pkt);
return;
}
pkt = ng_pktbuf_remove_snip(pkt, sixlowpan);
}
#ifdef MODULE_NG_SIXLOWPAN_FRAG
else if (sixlowpan_frag_is((sixlowpan_frag_t *)dispatch)) {
DEBUG("6lo: received 6LoWPAN fragment\n");
ng_sixlowpan_frag_handle_pkt(pkt);
return;
}
#endif
#ifdef MODULE_NG_SIXLOWPAN_IPHC
else if (sixlowpan_iphc_is(dispatch)) {
size_t dispatch_size;
ng_pktsnip_t *sixlowpan;
ng_pktsnip_t *ipv6 = ng_pktbuf_add(NULL, NULL, sizeof(ipv6_hdr_t),
NG_NETTYPE_IPV6);
if ((ipv6 == NULL) ||
(dispatch_size = ng_sixlowpan_iphc_decode(ipv6, pkt, 0)) == 0) {
DEBUG("6lo: error on IPHC decoding\n");
if (ipv6 != NULL) {
ng_pktbuf_release(ipv6);
}
ng_pktbuf_release(pkt);
return;
}
sixlowpan = ng_pktbuf_mark(pkt, dispatch_size, NG_NETTYPE_SIXLOWPAN);
if (sixlowpan == NULL) {
DEBUG("6lo: error on marking IPHC dispatch\n");
ng_pktbuf_release(ipv6);
ng_pktbuf_release(pkt);
return;
}
/* Remove IPHC dispatch */
ng_pktbuf_remove_snip(pkt, sixlowpan);
/* Insert IPv6 header instead */
ipv6->next = pkt->next;
pkt->next = ipv6;
}
#endif
else {
DEBUG("6lo: dispatch %02" PRIx8 " ... is not supported\n",
dispatch[0]);
ng_pktbuf_release(pkt);
return;
}
payload->type = NG_NETTYPE_IPV6;
if (!ng_netapi_dispatch_receive(NG_NETTYPE_IPV6, NG_NETREG_DEMUX_CTX_ALL, pkt)) {
DEBUG("6lo: No receivers for this packet found\n");
ng_pktbuf_release(pkt);
}
}
static void _receive(gnrc_pktsnip_t *pkt)
{
gnrc_pktsnip_t *payload;
uint8_t *dispatch;
/* seize payload as a temporary variable */
payload = gnrc_pktbuf_start_write(pkt); /* need to duplicate since pkt->next
* might get replaced */
if (payload == NULL) {
DEBUG("6lo: can not get write access on received packet\n");
#if defined(DEVELHELP) && ENABLE_DEBUG
gnrc_pktbuf_stats();
#endif
gnrc_pktbuf_release(pkt);
return;
}
pkt = payload; /* reset pkt from temporary variable */
payload = gnrc_pktsnip_search_type(pkt, GNRC_NETTYPE_SIXLOWPAN);
if ((payload == NULL) || (payload->size < 1)) {
DEBUG("6lo: Received packet has no 6LoWPAN payload\n");
gnrc_pktbuf_release(pkt);
return;
}
dispatch = payload->data;
if (dispatch[0] == SIXLOWPAN_UNCOMP) {
gnrc_pktsnip_t *sixlowpan;
DEBUG("6lo: received uncompressed IPv6 packet\n");
payload = gnrc_pktbuf_start_write(payload);
if (payload == NULL) {
DEBUG("6lo: can not get write access on received packet\n");
#if defined(DEVELHELP) && ENABLE_DEBUG
gnrc_pktbuf_stats();
#endif
gnrc_pktbuf_release(pkt);
return;
}
/* packet is uncompressed: just mark and remove the dispatch */
sixlowpan = gnrc_pktbuf_mark(payload, sizeof(uint8_t), GNRC_NETTYPE_SIXLOWPAN);
if (sixlowpan == NULL) {
DEBUG("6lo: can not mark 6LoWPAN dispatch\n");
gnrc_pktbuf_release(pkt);
return;
}
pkt = gnrc_pktbuf_remove_snip(pkt, sixlowpan);
payload->type = GNRC_NETTYPE_IPV6;
}
#ifdef MODULE_GNRC_SIXLOWPAN_FRAG
else if (sixlowpan_frag_is((sixlowpan_frag_t *)dispatch)) {
DEBUG("6lo: received 6LoWPAN fragment\n");
gnrc_sixlowpan_frag_handle_pkt(pkt);
return;
}
#endif
#ifdef MODULE_GNRC_SIXLOWPAN_IPHC
else if (sixlowpan_iphc_is(dispatch)) {
size_t dispatch_size, nh_len;
gnrc_pktsnip_t *sixlowpan;
gnrc_pktsnip_t *dec_hdr = gnrc_pktbuf_add(NULL, NULL, sizeof(ipv6_hdr_t),
GNRC_NETTYPE_IPV6);
if ((dec_hdr == NULL) ||
(dispatch_size = gnrc_sixlowpan_iphc_decode(&dec_hdr, pkt, 0, 0,
&nh_len)) == 0) {
DEBUG("6lo: error on IPHC decoding\n");
if (dec_hdr != NULL) {
gnrc_pktbuf_release(dec_hdr);
}
gnrc_pktbuf_release(pkt);
return;
}
sixlowpan = gnrc_pktbuf_mark(pkt, dispatch_size, GNRC_NETTYPE_SIXLOWPAN);
if (sixlowpan == NULL) {
DEBUG("6lo: error on marking IPHC dispatch\n");
gnrc_pktbuf_release(dec_hdr);
gnrc_pktbuf_release(pkt);
return;
}
/* Remove IPHC dispatches */
/* Insert decoded header instead */
pkt = gnrc_pktbuf_replace_snip(pkt, sixlowpan, dec_hdr);
payload->type = GNRC_NETTYPE_UNDEF;
}
#endif
else {
DEBUG("6lo: dispatch %02" PRIx8 " ... is not supported\n",
dispatch[0]);
gnrc_pktbuf_release(pkt);
return;
}
if (!gnrc_netapi_dispatch_receive(GNRC_NETTYPE_IPV6, GNRC_NETREG_DEMUX_CTX_ALL, pkt)) {
DEBUG("6lo: No receivers for this packet found\n");
gnrc_pktbuf_release(pkt);
}
}
void rbuf_add(gnrc_netif_hdr_t *netif_hdr, gnrc_pktsnip_t *pkt,
size_t offset, unsigned page)
{
rbuf_t *entry;
sixlowpan_frag_t *frag = pkt->data;
rbuf_int_t *ptr;
uint8_t *data = ((uint8_t *)pkt->data) + sizeof(sixlowpan_frag_t);
size_t frag_size;
rbuf_gc();
entry = _rbuf_get(gnrc_netif_hdr_get_src_addr(netif_hdr), netif_hdr->src_l2addr_len,
gnrc_netif_hdr_get_dst_addr(netif_hdr), netif_hdr->dst_l2addr_len,
byteorder_ntohs(frag->disp_size) & SIXLOWPAN_FRAG_SIZE_MASK,
byteorder_ntohs(frag->tag), page);
if (entry == NULL) {
DEBUG("6lo rbuf: reassembly buffer full.\n");
return;
}
ptr = entry->ints;
/* dispatches in the first fragment are ignored */
if (offset == 0) {
frag_size = pkt->size - sizeof(sixlowpan_frag_t);
if (data[0] == SIXLOWPAN_UNCOMP) {
frag_size--;
}
}
else {
frag_size = pkt->size - sizeof(sixlowpan_frag_n_t);
data++; /* FRAGN header is one byte longer (offset) */
}
if ((offset + frag_size) > entry->super.pkt->size) {
DEBUG("6lo rfrag: fragment too big for resulting datagram, discarding datagram\n");
gnrc_pktbuf_release(entry->super.pkt);
rbuf_rm(entry);
return;
}
/* If the fragment overlaps another fragment and differs in either the size
* or the offset of the overlapped fragment, discards the datagram
* https://tools.ietf.org/html/rfc4944#section-5.3 */
while (ptr != NULL) {
if (_rbuf_int_overlap_partially(ptr, offset, offset + frag_size - 1)) {
DEBUG("6lo rfrag: overlapping intervals, discarding datagram\n");
gnrc_pktbuf_release(entry->super.pkt);
rbuf_rm(entry);
/* "A fresh reassembly may be commenced with the most recently
* received link fragment"
* https://tools.ietf.org/html/rfc4944#section-5.3 */
rbuf_add(netif_hdr, pkt, offset, page);
return;
}
ptr = ptr->next;
}
if (_rbuf_update_ints(entry, offset, frag_size)) {
DEBUG("6lo rbuf: add fragment data\n");
entry->super.current_size += (uint16_t)frag_size;
if (offset == 0) {
#ifdef MODULE_GNRC_SIXLOWPAN_IPHC
if (sixlowpan_iphc_is(data)) {
gnrc_pktsnip_t *frag_hdr = gnrc_pktbuf_mark(pkt,
sizeof(sixlowpan_frag_t), GNRC_NETTYPE_SIXLOWPAN);
if (frag_hdr == NULL) {
gnrc_pktbuf_release(entry->super.pkt);
rbuf_rm(entry);
return;
}
gnrc_sixlowpan_iphc_recv(pkt, &entry->super, 0);
return;
}
else
#endif
if (data[0] == SIXLOWPAN_UNCOMP) {
data++;
}
}
memcpy(((uint8_t *)entry->super.pkt->data) + offset, data,
frag_size);
}
gnrc_sixlowpan_frag_rbuf_dispatch_when_complete(&entry->super, netif_hdr);
gnrc_pktbuf_release(pkt);
}
