Exemple #1
0
static gnrc_pktsnip_t *_recv(gnrc_netif_t *netif)
{
    netdev_t *dev = netif->dev;
    netdev_ieee802154_rx_info_t rx_info;
    gnrc_pktsnip_t *pkt = NULL;
    int bytes_expected = dev->driver->recv(dev, NULL, 0, NULL);

    if (bytes_expected >= (int)IEEE802154_MIN_FRAME_LEN) {
        int nread;

        pkt = gnrc_pktbuf_add(NULL, NULL, bytes_expected, GNRC_NETTYPE_UNDEF);
        if (pkt == NULL) {
            DEBUG("_recv_ieee802154: cannot allocate pktsnip.\n");
            /* Discard packet on netdev device */
            dev->driver->recv(dev, NULL, bytes_expected, NULL);
            return NULL;
        }
        nread = dev->driver->recv(dev, pkt->data, bytes_expected, &rx_info);
        if (nread <= 0) {
            gnrc_pktbuf_release(pkt);
            return NULL;
        }
#ifdef MODULE_NETSTATS_L2
        netif->stats.rx_count++;
        netif->stats.rx_bytes += nread;
#endif

        if (netif->flags & GNRC_NETIF_FLAGS_RAWMODE) {
            /* Raw mode, skip packet processing, but provide rx_info via
             * GNRC_NETTYPE_NETIF */
            gnrc_pktsnip_t *netif_snip = gnrc_netif_hdr_build(NULL, 0, NULL, 0);
            if (netif_snip == NULL) {
                DEBUG("_recv_ieee802154: no space left in packet buffer\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }
            gnrc_netif_hdr_t *hdr = netif_snip->data;
            hdr->lqi = rx_info.lqi;
            hdr->rssi = rx_info.rssi;
            hdr->if_pid = netif->pid;
            LL_APPEND(pkt, netif_snip);
        }
        else {
            /* Normal mode, try to parse the frame according to IEEE 802.15.4 */
            gnrc_pktsnip_t *ieee802154_hdr, *netif_hdr;
            gnrc_netif_hdr_t *hdr;
#if ENABLE_DEBUG
            char src_str[GNRC_NETIF_HDR_L2ADDR_PRINT_LEN];
#endif
            size_t mhr_len = ieee802154_get_frame_hdr_len(pkt->data);

            /* nread was checked for <= 0 before so we can safely cast it to
             * unsigned */
            if ((mhr_len == 0) || ((size_t)nread < mhr_len)) {
                DEBUG("_recv_ieee802154: illegally formatted frame received\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }
            nread -= mhr_len;
            /* mark IEEE 802.15.4 header */
            ieee802154_hdr = gnrc_pktbuf_mark(pkt, mhr_len, GNRC_NETTYPE_UNDEF);
            if (ieee802154_hdr == NULL) {
                DEBUG("_recv_ieee802154: no space left in packet buffer\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }
            netif_hdr = _make_netif_hdr(ieee802154_hdr->data);
            if (netif_hdr == NULL) {
                DEBUG("_recv_ieee802154: no space left in packet buffer\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }

            hdr = netif_hdr->data;

#ifdef MODULE_L2FILTER
            if (!l2filter_pass(dev->filter, gnrc_netif_hdr_get_src_addr(hdr),
                               hdr->src_l2addr_len)) {
                gnrc_pktbuf_release(pkt);
                gnrc_pktbuf_release(netif_hdr);
                DEBUG("_recv_ieee802154: packet dropped by l2filter\n");
                return NULL;
            }
#endif
#ifdef MODULE_GNRC_NETIF_DEDUP
            if (_already_received(netif, hdr, ieee802154_hdr->data)) {
                gnrc_pktbuf_release(pkt);
                gnrc_pktbuf_release(netif_hdr);
                DEBUG("_recv_ieee802154: packet dropped by deduplication\n");
                return NULL;
            }
            memcpy(netif->last_pkt.src, gnrc_netif_hdr_get_src_addr(hdr),
                   hdr->src_l2addr_len);
            netif->last_pkt.src_len = hdr->src_l2addr_len;
            netif->last_pkt.seq = ieee802154_get_seq(ieee802154_hdr->data);
#endif /* MODULE_GNRC_NETIF_DEDUP */

            hdr->lqi = rx_info.lqi;
            hdr->rssi = rx_info.rssi;
            hdr->if_pid = thread_getpid();
            dev->driver->get(dev, NETOPT_PROTO, &pkt->type, sizeof(pkt->type));
#if ENABLE_DEBUG
            DEBUG("_recv_ieee802154: received packet from %s of length %u\n",
                  gnrc_netif_addr_to_str(gnrc_netif_hdr_get_src_addr(hdr),
                                         hdr->src_l2addr_len,
                                         src_str),
                  nread);
#if defined(MODULE_OD)
            od_hex_dump(pkt->data, nread, OD_WIDTH_DEFAULT);
#endif
#endif
            gnrc_pktbuf_remove_snip(pkt, ieee802154_hdr);
            LL_APPEND(pkt, netif_hdr);
        }

        DEBUG("_recv_ieee802154: reallocating.\n");
        gnrc_pktbuf_realloc_data(pkt, nread);
    } else if (bytes_expected > 0) {
        DEBUG("_recv_ieee802154: received frame is too short\n");
        dev->driver->recv(dev, NULL, bytes_expected, NULL);
    }

    return pkt;
}
Exemple #2
0
static gnrc_pktsnip_t *_recv(gnrc_netif_t *netif)
{
    netdev_t *dev = netif->dev;
    netdev_ieee802154_rx_info_t rx_info;
    netdev_ieee802154_t *state = (netdev_ieee802154_t *)netif->dev;
    gnrc_pktsnip_t *pkt = NULL;
    int bytes_expected = dev->driver->recv(dev, NULL, 0, NULL);

    if (bytes_expected > 0) {
        int nread;

        pkt = gnrc_pktbuf_add(NULL, NULL, bytes_expected, GNRC_NETTYPE_UNDEF);
        if (pkt == NULL) {
            DEBUG("_recv_ieee802154: cannot allocate pktsnip.\n");
            return NULL;
        }
        nread = dev->driver->recv(dev, pkt->data, bytes_expected, &rx_info);
        if (nread <= 0) {
            gnrc_pktbuf_release(pkt);
            return NULL;
        }
        if (!(state->flags & NETDEV_IEEE802154_RAW)) {
            gnrc_pktsnip_t *ieee802154_hdr, *netif_hdr;
            gnrc_netif_hdr_t *hdr;
#if ENABLE_DEBUG
            char src_str[GNRC_NETIF_HDR_L2ADDR_PRINT_LEN];
#endif
            size_t mhr_len = ieee802154_get_frame_hdr_len(pkt->data);

            if (mhr_len == 0) {
                DEBUG("_recv_ieee802154: illegally formatted frame received\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }
            nread -= mhr_len;
            /* mark IEEE 802.15.4 header */
            ieee802154_hdr = gnrc_pktbuf_mark(pkt, mhr_len, GNRC_NETTYPE_UNDEF);
            if (ieee802154_hdr == NULL) {
                DEBUG("_recv_ieee802154: no space left in packet buffer\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }
            netif_hdr = _make_netif_hdr(ieee802154_hdr->data);
            if (netif_hdr == NULL) {
                DEBUG("_recv_ieee802154: no space left in packet buffer\n");
                gnrc_pktbuf_release(pkt);
                return NULL;
            }

            hdr = netif_hdr->data;

#ifdef MODULE_L2FILTER
            if (!l2filter_pass(dev->filter, gnrc_netif_hdr_get_src_addr(hdr),
                               hdr->src_l2addr_len)) {
                gnrc_pktbuf_release(pkt);
                gnrc_pktbuf_release(netif_hdr);
                DEBUG("_recv_ieee802154: packet dropped by l2filter\n");
                return NULL;
            }
#endif

            hdr->lqi = rx_info.lqi;
            hdr->rssi = rx_info.rssi;
            hdr->if_pid = thread_getpid();
            pkt->type = state->proto;
#if ENABLE_DEBUG
            DEBUG("_recv_ieee802154: received packet from %s of length %u\n",
                  gnrc_netif_addr_to_str(src_str, sizeof(src_str),
                                         gnrc_netif_hdr_get_src_addr(hdr),
                                         hdr->src_l2addr_len),
                  nread);
#if defined(MODULE_OD)
            od_hex_dump(pkt->data, nread, OD_WIDTH_DEFAULT);
#endif
#endif
            gnrc_pktbuf_remove_snip(pkt, ieee802154_hdr);
            LL_APPEND(pkt, netif_hdr);
        }

        DEBUG("_recv_ieee802154: reallocating.\n");
        gnrc_pktbuf_realloc_data(pkt, nread);
    }

    return pkt;
}