hostap_info.c

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/* Host AP driver Info Frame processing (part of hostap.o module) */


/* Called only as a tasklet (software IRQ) */
static void prism2_info_commtallies16(local_info_t *local, unsigned char *buf,
                                      int left)
{
        struct hfa384x_comm_tallies *tallies;

        if (left < sizeof(struct hfa384x_comm_tallies)) {
                printk(KERN_DEBUG "%s: too short (len=%d) commtallies "
                       "info frame\n", local->dev->name, left);
                return;
        }

        tallies = (struct hfa384x_comm_tallies *) buf;
#define ADD_COMM_TALLIES(name) \
local->comm_tallies.name += le16_to_cpu(tallies->name)
        ADD_COMM_TALLIES(tx_unicast_frames);
        ADD_COMM_TALLIES(tx_multicast_frames);
        ADD_COMM_TALLIES(tx_fragments);
        ADD_COMM_TALLIES(tx_unicast_octets);
        ADD_COMM_TALLIES(tx_multicast_octets);
        ADD_COMM_TALLIES(tx_deferred_transmissions);
        ADD_COMM_TALLIES(tx_single_retry_frames);
        ADD_COMM_TALLIES(tx_multiple_retry_frames);
        ADD_COMM_TALLIES(tx_retry_limit_exceeded);
        ADD_COMM_TALLIES(tx_discards);
        ADD_COMM_TALLIES(rx_unicast_frames);
        ADD_COMM_TALLIES(rx_multicast_frames);
        ADD_COMM_TALLIES(rx_fragments);
        ADD_COMM_TALLIES(rx_unicast_octets);
        ADD_COMM_TALLIES(rx_multicast_octets);
        ADD_COMM_TALLIES(rx_fcs_errors);
        ADD_COMM_TALLIES(rx_discards_no_buffer);
        ADD_COMM_TALLIES(tx_discards_wrong_sa);
        ADD_COMM_TALLIES(rx_discards_wep_undecryptable);
        ADD_COMM_TALLIES(rx_message_in_msg_fragments);
        ADD_COMM_TALLIES(rx_message_in_bad_msg_fragments);
#undef ADD_COMM_TALLIES
}


/* Called only as a tasklet (software IRQ) */
static void prism2_info_commtallies32(local_info_t *local, unsigned char *buf,
                                      int left)
{
        struct hfa384x_comm_tallies32 *tallies;

        if (left < sizeof(struct hfa384x_comm_tallies32)) {
                printk(KERN_DEBUG "%s: too short (len=%d) commtallies32 "
                       "info frame\n", local->dev->name, left);
                return;
        }

        tallies = (struct hfa384x_comm_tallies32 *) buf;
#define ADD_COMM_TALLIES(name) \
local->comm_tallies.name += le32_to_cpu(tallies->name)
        ADD_COMM_TALLIES(tx_unicast_frames);
        ADD_COMM_TALLIES(tx_multicast_frames);
        ADD_COMM_TALLIES(tx_fragments);
        ADD_COMM_TALLIES(tx_unicast_octets);
        ADD_COMM_TALLIES(tx_multicast_octets);
        ADD_COMM_TALLIES(tx_deferred_transmissions);
        ADD_COMM_TALLIES(tx_single_retry_frames);
        ADD_COMM_TALLIES(tx_multiple_retry_frames);
        ADD_COMM_TALLIES(tx_retry_limit_exceeded);
        ADD_COMM_TALLIES(tx_discards);
        ADD_COMM_TALLIES(rx_unicast_frames);
        ADD_COMM_TALLIES(rx_multicast_frames);
        ADD_COMM_TALLIES(rx_fragments);
        ADD_COMM_TALLIES(rx_unicast_octets);
        ADD_COMM_TALLIES(rx_multicast_octets);
        ADD_COMM_TALLIES(rx_fcs_errors);
        ADD_COMM_TALLIES(rx_discards_no_buffer);
        ADD_COMM_TALLIES(tx_discards_wrong_sa);
        ADD_COMM_TALLIES(rx_discards_wep_undecryptable);
        ADD_COMM_TALLIES(rx_message_in_msg_fragments);
        ADD_COMM_TALLIES(rx_message_in_bad_msg_fragments);
#undef ADD_COMM_TALLIES
}


/* Called only as a tasklet (software IRQ) */
static void prism2_info_commtallies(local_info_t *local, unsigned char *buf,
                                    int left)
{
        if (local->tallies32)
                prism2_info_commtallies32(local, buf, left);
        else
                prism2_info_commtallies16(local, buf, left);
}


#ifndef PRISM2_NO_STATION_MODES
#ifndef PRISM2_NO_DEBUG
static const char* hfa384x_linkstatus_str(u16 linkstatus)
{
        switch (linkstatus) {
        case HFA384X_LINKSTATUS_CONNECTED:
                return "Connected";
        case HFA384X_LINKSTATUS_DISCONNECTED:
                return "Disconnected";
        case HFA384X_LINKSTATUS_AP_CHANGE:
                return "Access point change";
        case HFA384X_LINKSTATUS_AP_OUT_OF_RANGE:
                return "Access point out of range";
        case HFA384X_LINKSTATUS_AP_IN_RANGE:
                return "Access point in range";
        case HFA384X_LINKSTATUS_ASSOC_FAILED:
                return "Association failed";
        default:
                return "Unknown";
        }
}
#endif /* PRISM2_NO_DEBUG */


/* Called only as a tasklet (software IRQ) */
static void prism2_info_linkstatus(local_info_t *local, unsigned char *buf,
                                    int left)
{
        u16 val;
        int non_sta_mode;

        /* Alloc new JoinRequests to occur since LinkStatus for the previous
         * has been received */
        local->last_join_time = 0;

        if (left != 2) {
                printk(KERN_DEBUG "%s: invalid linkstatus info frame "
                       "length %d\n", local->dev->name, left);
                return;
        }

        non_sta_mode = local->iw_mode == IW_MODE_MASTER ||
                local->iw_mode == IW_MODE_REPEAT ||
                local->iw_mode == IW_MODE_MONITOR;

        val = buf[0] | (buf[1] << 8);
        if (!non_sta_mode || val != HFA384X_LINKSTATUS_DISCONNECTED) {
                PDEBUG(DEBUG_EXTRA, "%s: LinkStatus=%d (%s)\n",
                       local->dev->name, val, hfa384x_linkstatus_str(val));
        }

        if (non_sta_mode)
                return;

        /* Get current BSSID later in scheduled task */
        set_bit(PRISM2_INFO_PENDING_LINKSTATUS, &local->pending_info);
        local->prev_link_status = val;
        PRISM2_SCHEDULE_TASK(&local->info_queue);
}


static void prism2_host_roaming(local_info_t *local)
{
        struct hfa384x_join_request req;
        struct net_device *dev = local->dev;
        struct hfa384x_scan_result *selected, *entry;
        int i;
        unsigned long flags;

        if (local->last_join_time &&
            time_before(jiffies, local->last_join_time + 10 * HZ)) {
                PDEBUG(DEBUG_EXTRA, "%s: last join request has not yet been "
                       "completed - waiting for it before issuing new one\n",
                       dev->name);
                return;
        }

        /* ScanResults are sorted: first ESS results in decreasing signal
         * quality then IBSS results in similar order.
         * Trivial roaming policy: just select the first entry.
         * This could probably be improved by adding hysteresis to limit
         * number of handoffs, etc.
         *
         * Could do periodic RID_SCANREQUEST or Inquire F101 to get new
         * ScanResults */
        spin_lock_irqsave(&local->lock, flags);
        if (local->last_scan_results == NULL ||
            local->last_scan_results_count == 0) {
                spin_unlock_irqrestore(&local->lock, flags);
                PDEBUG(DEBUG_EXTRA, "%s: no scan results for host roaming\n",
                       dev->name);
                return;
        }

        selected = &local->last_scan_results[0];

        if (local->preferred_ap[0] || local->preferred_ap[1] ||
            local->preferred_ap[2] || local->preferred_ap[3] ||
            local->preferred_ap[4] || local->preferred_ap[5]) {
                /* Try to find preferred AP */
                PDEBUG(DEBUG_EXTRA, "%s: Preferred AP BSSID " MACSTR "\n",
                       dev->name, MAC2STR(local->preferred_ap));
                for (i = 0; i < local->last_scan_results_count; i++) {
                        entry = &local->last_scan_results[i];
                        if (memcmp(local->preferred_ap, entry->bssid, 6) == 0)
                        {
                                PDEBUG(DEBUG_EXTRA, "%s: using preferred AP "
                                       "selection\n", dev->name);
                                selected = entry;
                                break;
                        }
                }
        }

        memcpy(req.bssid, selected->bssid, 6);
        req.channel = selected->chid;
        spin_unlock_irqrestore(&local->lock, flags);

        PDEBUG(DEBUG_EXTRA, "%s: JoinRequest: BSSID=" MACSTR " channel=%d\n",
               dev->name, MAC2STR(req.bssid), le16_to_cpu(req.channel));
        if (local->func->set_rid(dev, HFA384X_RID_JOINREQUEST, &req,
                                 sizeof(req))) {
                printk(KERN_DEBUG "%s: JoinRequest failed\n", dev->name);
        }
        local->last_join_time = jiffies;
}


#if WIRELESS_EXT > 13
static void hostap_report_scan_complete(local_info_t *local)
{
        union iwreq_data wrqu;

        /* Inform user space about new scan results (just empty event,
         * SIOCGIWSCAN can be used to fetch data */
        wrqu.data.length = 0;
        wrqu.data.flags = 0;
        wireless_send_event(local->dev, SIOCGIWSCAN, &wrqu, NULL);

        /* Allow SIOCGIWSCAN handling to occur since we have received
         * scanning result */
        local->scan_timestamp = 0;
}
#else /* WIRELESS_EXT > 13 */
static inline void hostap_report_scan_complete(local_info_t *local)
{
}
#endif /* WIRELESS_EXT > 13 */


/* Called only as a tasklet (software IRQ) */
static void prism2_info_scanresults(local_info_t *local, unsigned char *buf,
                                    int left)
{
        u16 *pos;
        int new_count;
        unsigned long flags;
        struct hfa384x_scan_result *results, *prev;

        if (left < 4) {
                printk(KERN_DEBUG "%s: invalid scanresult info frame "
                       "length %d\n", local->dev->name, left);
                return;
        }

        pos = (u16 *) buf;
        pos++;
        pos++;
        left -= 4;

        new_count = left / sizeof(struct hfa384x_scan_result);
        results = kmalloc(new_count * sizeof(struct hfa384x_scan_result),
                          GFP_ATOMIC);
        if (results == NULL)
                return;
        memcpy(results, pos, new_count * sizeof(struct hfa384x_scan_result));

        spin_lock_irqsave(&local->lock, flags);
        local->last_scan_type = PRISM2_SCAN;
        prev = local->last_scan_results;
        local->last_scan_results = results;
        local->last_scan_results_count = new_count;
        spin_unlock_irqrestore(&local->lock, flags);
        kfree(prev);

        hostap_report_scan_complete(local);

        /* Perform rest of ScanResults handling later in scheduled task */
        set_bit(PRISM2_INFO_PENDING_SCANRESULTS, &local->pending_info);
        PRISM2_SCHEDULE_TASK(&local->info_queue);
}


/* Called only as a tasklet (software IRQ) */
static void prism2_info_hostscanresults(local_info_t *local,
                                        unsigned char *buf, int left)
{
        int i, result_size, copy_len, new_count;
        struct hfa384x_hostscan_result *results, *prev;
        unsigned long flags;
        u16 *pos;
        u8 *ptr;

        wake_up_interruptible(&local->hostscan_wq);

        if (left < 4) {
                printk(KERN_DEBUG "%s: invalid hostscanresult info frame "
                       "length %d\n", local->dev->name, left);
                return;
        }

        pos = (u16 *) buf;
        copy_len = result_size = le16_to_cpu(*pos);
        if (result_size == 0) {
                printk(KERN_DEBUG "%s: invalid result_size (0) in "
                       "hostscanresults\n", local->dev->name);
                return;
        }
        if (copy_len > sizeof(struct hfa384x_hostscan_result))
                copy_len = sizeof(struct hfa384x_hostscan_result);

        pos++;
        pos++;
        left -= 4;
        ptr = (u8 *) pos;

        new_count = left / result_size;
        results = kmalloc(new_count * sizeof(struct hfa384x_hostscan_result),
                          GFP_ATOMIC);
        if (results == NULL)
                return;
        memset(results, 0, new_count * sizeof(struct hfa384x_hostscan_result));

        for (i = 0; i < new_count; i++) {
                memcpy(&results[i], ptr, copy_len);
                ptr += result_size;
                left -= result_size;
        }

        if (left) {
                printk(KERN_DEBUG "%s: short HostScan result entry (%d/%d)\n",
                       local->dev->name, left, result_size);
        }

        spin_lock_irqsave(&local->lock, flags);
        local->last_scan_type = PRISM2_HOSTSCAN;
        prev = local->last_hostscan_results;
        local->last_hostscan_results = results;
        local->last_hostscan_results_count = new_count;
        spin_unlock_irqrestore(&local->lock, flags);
        kfree(prev);

        hostap_report_scan_complete(local);
}
#endif /* PRISM2_NO_STATION_MODES */


/* Called only as a tasklet (software IRQ) */
void hostap_info_process(local_info_t *local, struct sk_buff *skb)
{
        struct hfa384x_info_frame *info;
        unsigned char *buf;
        int left;
#ifndef PRISM2_NO_DEBUG
        int i;
#endif /* PRISM2_NO_DEBUG */

        info = (struct hfa384x_info_frame *) skb->data;
        buf = skb->data + sizeof(*info);
        left = skb->len - sizeof(*info);

        switch (info->type) {
        case HFA384X_INFO_COMMTALLIES:
                prism2_info_commtallies(local, buf, left);
                break;

#ifndef PRISM2_NO_STATION_MODES
        case HFA384X_INFO_LINKSTATUS:
                prism2_info_linkstatus(local, buf, left);
                break;

        case HFA384X_INFO_SCANRESULTS:
                prism2_info_scanresults(local, buf, left);
                break;

        case HFA384X_INFO_HOSTSCANRESULTS:
                prism2_info_hostscanresults(local, buf, left);
                break;
#endif /* PRISM2_NO_STATION_MODES */

#ifndef PRISM2_NO_DEBUG
        default:
                PDEBUG(DEBUG_EXTRA, "%s: INFO - len=%d type=0x%04x\n",
                       local->dev->name, info->len, info->type);
                PDEBUG(DEBUG_EXTRA, "Unknown info frame:");
                for (i = 0; i < (left < 100 ? left : 100); i++)
                        PDEBUG2(DEBUG_EXTRA, " %02x", buf[i]);
                PDEBUG2(DEBUG_EXTRA, "\n");
                break;
#endif /* PRISM2_NO_DEBUG */
        }
}


#ifndef PRISM2_NO_STATION_MODES
static void handle_info_queue_linkstatus(local_info_t *local)
{
        int val = local->prev_link_status;
        int connected;

        connected =
                val == HFA384X_LINKSTATUS_CONNECTED ||
                val == HFA384X_LINKSTATUS_AP_CHANGE ||
                val == HFA384X_LINKSTATUS_AP_IN_RANGE;

        if (local->func->get_rid(local->dev, HFA384X_RID_CURRENTBSSID,
                                 local->bssid, ETH_ALEN, 1) < 0) {
                printk(KERN_DEBUG "%s: could not read CURRENTBSSID after "
                       "LinkStatus event\n", local->dev->name);
        } else {
                PDEBUG(DEBUG_EXTRA, "%s: LinkStatus: BSSID=" MACSTR "\n",
                       local->dev->name,
                       MAC2STR((unsigned char *) local->bssid));
                if (local->wds_type & HOSTAP_WDS_AP_CLIENT)
                        hostap_add_sta(local->ap, local->bssid);
        }

#if WIRELESS_EXT > 13
        {
                union iwreq_data wrqu;

                /* Get BSSID if we have a valid AP address */
                if (connected)
                        memcpy(wrqu.ap_addr.sa_data, local->bssid, ETH_ALEN);
                else
                        memset(wrqu.ap_addr.sa_data, 0, ETH_ALEN);
                wrqu.ap_addr.sa_family = ARPHRD_ETHER;
                wireless_send_event(local->dev, SIOCGIWAP, &wrqu, NULL);
        }
#endif /* WIRELESS_EXT > 13 */
}


static void handle_info_queue_scanresults(local_info_t *local)
{
        if (local->host_roaming == 1 && local->iw_mode == IW_MODE_INFRA)
                prism2_host_roaming(local);
}


/* Called only as scheduled task after receiving info frames (used to avoid
 * pending too much time in HW IRQ handler). */
static void handle_info_queue(void *data)
{
        local_info_t *local = (local_info_t *) data;

        if (test_and_clear_bit(PRISM2_INFO_PENDING_LINKSTATUS,
                               &local->pending_info))
                handle_info_queue_linkstatus(local);

        if (test_and_clear_bit(PRISM2_INFO_PENDING_SCANRESULTS,
                               &local->pending_info))
                handle_info_queue_scanresults(local);

#ifndef NEW_MODULE_CODE
        MOD_DEC_USE_COUNT;
#endif
}
#endif /* PRISM2_NO_STATION_MODES */


void hostap_info_init(local_info_t *local)
{
        skb_queue_head_init(&local->info_list);
#ifndef PRISM2_NO_STATION_MODES
        INIT_WORK(&local->info_queue, handle_info_queue, local);
#endif /* PRISM2_NO_STATION_MODES */
}


EXPORT_SYMBOL(hostap_info_init);
EXPORT_SYMBOL(hostap_info_process);

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