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); } }
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); }