[people/ms/linux.git] / drivers / net / wireless / intersil / hostap / hostap_ap.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Intersil Prism2 driver with Host AP (software access point) support
 * Copyright (c) 2001-2002, SSH Communications Security Corp and Jouni Malinen
 * <j@w1.fi>
 * Copyright (c) 2002-2005, Jouni Malinen <j@w1.fi>
 *
 * This file is to be included into hostap.c when S/W AP functionality is
 * compiled.
 *
 * AP:  FIX:
 * - if unicast Class 2 (assoc,reassoc,disassoc) frame received from
 *   unauthenticated STA, send deauth. frame (8802.11: 5.5)
 * - if unicast Class 3 (data with to/from DS,deauth,pspoll) frame received
 *   from authenticated, but unassoc STA, send disassoc frame (8802.11: 5.5)
 * - if unicast Class 3 received from unauthenticated STA, send deauth. frame
 *   (8802.11: 5.5)
 */

#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/random.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/moduleparam.h>
#include <linux/etherdevice.h>

#include "hostap_wlan.h"
#include "hostap.h"
#include "hostap_ap.h"

static int other_ap_policy[MAX_PARM_DEVICES] = { AP_OTHER_AP_SKIP_ALL,
                                                 DEF_INTS };
module_param_array(other_ap_policy, int, NULL, 0444);
MODULE_PARM_DESC(other_ap_policy, "Other AP beacon monitoring policy (0-3)");

static int ap_max_inactivity[MAX_PARM_DEVICES] = { AP_MAX_INACTIVITY_SEC,
                                                   DEF_INTS };
module_param_array(ap_max_inactivity, int, NULL, 0444);
MODULE_PARM_DESC(ap_max_inactivity, "AP timeout (in seconds) for station "
                 "inactivity");

static int ap_bridge_packets[MAX_PARM_DEVICES] = { 1, DEF_INTS };
module_param_array(ap_bridge_packets, int, NULL, 0444);
MODULE_PARM_DESC(ap_bridge_packets, "Bridge packets directly between "
                 "stations");

static int autom_ap_wds[MAX_PARM_DEVICES] = { 0, DEF_INTS };
module_param_array(autom_ap_wds, int, NULL, 0444);
MODULE_PARM_DESC(autom_ap_wds, "Add WDS connections to other APs "
                 "automatically");


static struct sta_info* ap_get_sta(struct ap_data *ap, u8 *sta);
static void hostap_event_expired_sta(struct net_device *dev,
                                     struct sta_info *sta);
static void handle_add_proc_queue(struct work_struct *work);

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
static void handle_wds_oper_queue(struct work_struct *work);
static void prism2_send_mgmt(struct net_device *dev,
                             u16 type_subtype, char *body,
                             int body_len, u8 *addr, u16 tx_cb_idx);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


#if !defined(PRISM2_NO_PROCFS_DEBUG) && defined(CONFIG_PROC_FS)
static int ap_debug_proc_show(struct seq_file *m, void *v)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));

        seq_printf(m, "BridgedUnicastFrames=%u\n", ap->bridged_unicast);
        seq_printf(m, "BridgedMulticastFrames=%u\n", ap->bridged_multicast);
        seq_printf(m, "max_inactivity=%u\n", ap->max_inactivity / HZ);
        seq_printf(m, "bridge_packets=%u\n", ap->bridge_packets);
        seq_printf(m, "nullfunc_ack=%u\n", ap->nullfunc_ack);
        seq_printf(m, "autom_ap_wds=%u\n", ap->autom_ap_wds);
        seq_printf(m, "auth_algs=%u\n", ap->local->auth_algs);
        seq_printf(m, "tx_drop_nonassoc=%u\n", ap->tx_drop_nonassoc);
        return 0;
}
#endif

static void ap_sta_hash_add(struct ap_data *ap, struct sta_info *sta)
{
        sta->hnext = ap->sta_hash[STA_HASH(sta->addr)];
        ap->sta_hash[STA_HASH(sta->addr)] = sta;
}

static void ap_sta_hash_del(struct ap_data *ap, struct sta_info *sta)
{
        struct sta_info *s;

        s = ap->sta_hash[STA_HASH(sta->addr)];
        if (s == NULL) return;
        if (ether_addr_equal(s->addr, sta->addr)) {
                ap->sta_hash[STA_HASH(sta->addr)] = s->hnext;
                return;
        }

        while (s->hnext != NULL && !ether_addr_equal(s->hnext->addr, sta->addr))
                s = s->hnext;
        if (s->hnext != NULL)
                s->hnext = s->hnext->hnext;
        else
                printk("AP: could not remove STA %pM from hash table\n",
                       sta->addr);
}

static void ap_free_sta(struct ap_data *ap, struct sta_info *sta)
{
        if (sta->ap && sta->local)
                hostap_event_expired_sta(sta->local->dev, sta);

        if (ap->proc != NULL) {
                char name[20];
                sprintf(name, "%pM", sta->addr);
                remove_proc_entry(name, ap->proc);
        }

        if (sta->crypt) {
                sta->crypt->ops->deinit(sta->crypt->priv);
                kfree(sta->crypt);
                sta->crypt = NULL;
        }

        skb_queue_purge(&sta->tx_buf);

        ap->num_sta--;
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        if (sta->aid > 0)
                ap->sta_aid[sta->aid - 1] = NULL;

        if (!sta->ap)
                kfree(sta->u.sta.challenge);
        del_timer_sync(&sta->timer);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        kfree(sta);
}


static void hostap_set_tim(local_info_t *local, int aid, int set)
{
        if (local->func->set_tim)
                local->func->set_tim(local->dev, aid, set);
}


static void hostap_event_new_sta(struct net_device *dev, struct sta_info *sta)
{
        union iwreq_data wrqu;
        memset(&wrqu, 0, sizeof(wrqu));
        memcpy(wrqu.addr.sa_data, sta->addr, ETH_ALEN);
        wrqu.addr.sa_family = ARPHRD_ETHER;
        wireless_send_event(dev, IWEVREGISTERED, &wrqu, NULL);
}


static void hostap_event_expired_sta(struct net_device *dev,
                                     struct sta_info *sta)
{
        union iwreq_data wrqu;
        memset(&wrqu, 0, sizeof(wrqu));
        memcpy(wrqu.addr.sa_data, sta->addr, ETH_ALEN);
        wrqu.addr.sa_family = ARPHRD_ETHER;
        wireless_send_event(dev, IWEVEXPIRED, &wrqu, NULL);
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT

static void ap_handle_timer(struct timer_list *t)
{
        struct sta_info *sta = from_timer(sta, t, timer);
        local_info_t *local;
        struct ap_data *ap;
        unsigned long next_time = 0;
        int was_assoc;

        if (sta == NULL || sta->local == NULL || sta->local->ap == NULL) {
                PDEBUG(DEBUG_AP, "ap_handle_timer() called with NULL data\n");
                return;
        }

        local = sta->local;
        ap = local->ap;
        was_assoc = sta->flags & WLAN_STA_ASSOC;

        if (atomic_read(&sta->users) != 0)
                next_time = jiffies + HZ;
        else if ((sta->flags & WLAN_STA_PERM) && !(sta->flags & WLAN_STA_AUTH))
                next_time = jiffies + ap->max_inactivity;

        if (time_before(jiffies, sta->last_rx + ap->max_inactivity)) {
                /* station activity detected; reset timeout state */
                sta->timeout_next = STA_NULLFUNC;
                next_time = sta->last_rx + ap->max_inactivity;
        } else if (sta->timeout_next == STA_DISASSOC &&
                   !(sta->flags & WLAN_STA_PENDING_POLL)) {
                /* STA ACKed data nullfunc frame poll */
                sta->timeout_next = STA_NULLFUNC;
                next_time = jiffies + ap->max_inactivity;
        }

        if (next_time) {
                sta->timer.expires = next_time;
                add_timer(&sta->timer);
                return;
        }

        if (sta->ap)
                sta->timeout_next = STA_DEAUTH;

        if (sta->timeout_next == STA_DEAUTH && !(sta->flags & WLAN_STA_PERM)) {
                spin_lock(&ap->sta_table_lock);
                ap_sta_hash_del(ap, sta);
                list_del(&sta->list);
                spin_unlock(&ap->sta_table_lock);
                sta->flags &= ~(WLAN_STA_AUTH | WLAN_STA_ASSOC);
        } else if (sta->timeout_next == STA_DISASSOC)
                sta->flags &= ~WLAN_STA_ASSOC;

        if (was_assoc && !(sta->flags & WLAN_STA_ASSOC) && !sta->ap)
                hostap_event_expired_sta(local->dev, sta);

        if (sta->timeout_next == STA_DEAUTH && sta->aid > 0 &&
            !skb_queue_empty(&sta->tx_buf)) {
                hostap_set_tim(local, sta->aid, 0);
                sta->flags &= ~WLAN_STA_TIM;
        }

        if (sta->ap) {
                if (ap->autom_ap_wds) {
                        PDEBUG(DEBUG_AP, "%s: removing automatic WDS "
                               "connection to AP %pM\n",
                               local->dev->name, sta->addr);
                        hostap_wds_link_oper(local, sta->addr, WDS_DEL);
                }
        } else if (sta->timeout_next == STA_NULLFUNC) {
                /* send data frame to poll STA and check whether this frame
                 * is ACKed */
                /* FIX: IEEE80211_STYPE_NULLFUNC would be more appropriate, but
                 * it is apparently not retried so TX Exc events are not
                 * received for it */
                sta->flags |= WLAN_STA_PENDING_POLL;
                prism2_send_mgmt(local->dev, IEEE80211_FTYPE_DATA |
                                 IEEE80211_STYPE_DATA, NULL, 0,
                                 sta->addr, ap->tx_callback_poll);
        } else {
                int deauth = sta->timeout_next == STA_DEAUTH;
                __le16 resp;
                PDEBUG(DEBUG_AP, "%s: sending %s info to STA %pM"
                       "(last=%lu, jiffies=%lu)\n",
                       local->dev->name,
                       deauth ? "deauthentication" : "disassociation",
                       sta->addr, sta->last_rx, jiffies);

                resp = cpu_to_le16(deauth ? WLAN_REASON_PREV_AUTH_NOT_VALID :
                                   WLAN_REASON_DISASSOC_DUE_TO_INACTIVITY);
                prism2_send_mgmt(local->dev, IEEE80211_FTYPE_MGMT |
                                 (deauth ? IEEE80211_STYPE_DEAUTH :
                                  IEEE80211_STYPE_DISASSOC),
                                 (char *) &resp, 2, sta->addr, 0);
        }

        if (sta->timeout_next == STA_DEAUTH) {
                if (sta->flags & WLAN_STA_PERM) {
                        PDEBUG(DEBUG_AP, "%s: STA %pM"
                               " would have been removed, "
                               "but it has 'perm' flag\n",
                               local->dev->name, sta->addr);
                } else
                        ap_free_sta(ap, sta);
                return;
        }

        if (sta->timeout_next == STA_NULLFUNC) {
                sta->timeout_next = STA_DISASSOC;
                sta->timer.expires = jiffies + AP_DISASSOC_DELAY;
        } else {
                sta->timeout_next = STA_DEAUTH;
                sta->timer.expires = jiffies + AP_DEAUTH_DELAY;
        }

        add_timer(&sta->timer);
}


void hostap_deauth_all_stas(struct net_device *dev, struct ap_data *ap,
                            int resend)
{
        u8 addr[ETH_ALEN];
        __le16 resp;
        int i;

        PDEBUG(DEBUG_AP, "%s: Deauthenticate all stations\n", dev->name);
        eth_broadcast_addr(addr);

        resp = cpu_to_le16(WLAN_REASON_PREV_AUTH_NOT_VALID);

        /* deauth message sent; try to resend it few times; the message is
         * broadcast, so it may be delayed until next DTIM; there is not much
         * else we can do at this point since the driver is going to be shut
         * down */
        for (i = 0; i < 5; i++) {
                prism2_send_mgmt(dev, IEEE80211_FTYPE_MGMT |
                                 IEEE80211_STYPE_DEAUTH,
                                 (char *) &resp, 2, addr, 0);

                if (!resend || ap->num_sta <= 0)
                        return;

                mdelay(50);
        }
}


static int ap_control_proc_show(struct seq_file *m, void *v)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        char *policy_txt;
        struct mac_entry *entry;

        if (v == SEQ_START_TOKEN) {
                switch (ap->mac_restrictions.policy) {
                case MAC_POLICY_OPEN:
                        policy_txt = "open";
                        break;
                case MAC_POLICY_ALLOW:
                        policy_txt = "allow";
                        break;
                case MAC_POLICY_DENY:
                        policy_txt = "deny";
                        break;
                default:
                        policy_txt = "unknown";
                        break;
                }
                seq_printf(m, "MAC policy: %s\n", policy_txt);
                seq_printf(m, "MAC entries: %u\n", ap->mac_restrictions.entries);
                seq_puts(m, "MAC list:\n");
                return 0;
        }

        entry = v;
        seq_printf(m, "%pM\n", entry->addr);
        return 0;
}

static void *ap_control_proc_start(struct seq_file *m, loff_t *_pos)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        spin_lock_bh(&ap->mac_restrictions.lock);
        return seq_list_start_head(&ap->mac_restrictions.mac_list, *_pos);
}

static void *ap_control_proc_next(struct seq_file *m, void *v, loff_t *_pos)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        return seq_list_next(v, &ap->mac_restrictions.mac_list, _pos);
}

static void ap_control_proc_stop(struct seq_file *m, void *v)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        spin_unlock_bh(&ap->mac_restrictions.lock);
}

static const struct seq_operations ap_control_proc_seqops = {
        .start  = ap_control_proc_start,
        .next   = ap_control_proc_next,
        .stop   = ap_control_proc_stop,
        .show   = ap_control_proc_show,
};

int ap_control_add_mac(struct mac_restrictions *mac_restrictions, u8 *mac)
{
        struct mac_entry *entry;

        entry = kmalloc(sizeof(struct mac_entry), GFP_KERNEL);
        if (entry == NULL)
                return -ENOMEM;

        memcpy(entry->addr, mac, ETH_ALEN);

        spin_lock_bh(&mac_restrictions->lock);
        list_add_tail(&entry->list, &mac_restrictions->mac_list);
        mac_restrictions->entries++;
        spin_unlock_bh(&mac_restrictions->lock);

        return 0;
}


int ap_control_del_mac(struct mac_restrictions *mac_restrictions, u8 *mac)
{
        struct list_head *ptr;
        struct mac_entry *entry;

        spin_lock_bh(&mac_restrictions->lock);
        for (ptr = mac_restrictions->mac_list.next;
             ptr != &mac_restrictions->mac_list; ptr = ptr->next) {
                entry = list_entry(ptr, struct mac_entry, list);

                if (ether_addr_equal(entry->addr, mac)) {
                        list_del(ptr);
                        kfree(entry);
                        mac_restrictions->entries--;
                        spin_unlock_bh(&mac_restrictions->lock);
                        return 0;
                }
        }
        spin_unlock_bh(&mac_restrictions->lock);
        return -1;
}


static int ap_control_mac_deny(struct mac_restrictions *mac_restrictions,
                               u8 *mac)
{
        struct mac_entry *entry;
        int found = 0;

        if (mac_restrictions->policy == MAC_POLICY_OPEN)
                return 0;

        spin_lock_bh(&mac_restrictions->lock);
        list_for_each_entry(entry, &mac_restrictions->mac_list, list) {
                if (ether_addr_equal(entry->addr, mac)) {
                        found = 1;
                        break;
                }
        }
        spin_unlock_bh(&mac_restrictions->lock);

        if (mac_restrictions->policy == MAC_POLICY_ALLOW)
                return !found;
        else
                return found;
}


void ap_control_flush_macs(struct mac_restrictions *mac_restrictions)
{
        struct list_head *ptr, *n;
        struct mac_entry *entry;

        if (mac_restrictions->entries == 0)
                return;

        spin_lock_bh(&mac_restrictions->lock);
        for (ptr = mac_restrictions->mac_list.next, n = ptr->next;
             ptr != &mac_restrictions->mac_list;
             ptr = n, n = ptr->next) {
                entry = list_entry(ptr, struct mac_entry, list);
                list_del(ptr);
                kfree(entry);
        }
        mac_restrictions->entries = 0;
        spin_unlock_bh(&mac_restrictions->lock);
}


int ap_control_kick_mac(struct ap_data *ap, struct net_device *dev, u8 *mac)
{
        struct sta_info *sta;
        __le16 resp;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, mac);
        if (sta) {
                ap_sta_hash_del(ap, sta);
                list_del(&sta->list);
        }
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta)
                return -EINVAL;

        resp = cpu_to_le16(WLAN_REASON_PREV_AUTH_NOT_VALID);
        prism2_send_mgmt(dev, IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_DEAUTH,
                         (char *) &resp, 2, sta->addr, 0);

        if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap)
                hostap_event_expired_sta(dev, sta);

        ap_free_sta(ap, sta);

        return 0;
}

#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


void ap_control_kickall(struct ap_data *ap)
{
        struct list_head *ptr, *n;
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        for (ptr = ap->sta_list.next, n = ptr->next; ptr != &ap->sta_list;
             ptr = n, n = ptr->next) {
                sta = list_entry(ptr, struct sta_info, list);
                ap_sta_hash_del(ap, sta);
                list_del(&sta->list);
                if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap && sta->local)
                        hostap_event_expired_sta(sta->local->dev, sta);
                ap_free_sta(ap, sta);
        }
        spin_unlock_bh(&ap->sta_table_lock);
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT

static int prism2_ap_proc_show(struct seq_file *m, void *v)
{
        struct sta_info *sta = v;
        int i;

        if (v == SEQ_START_TOKEN) {
                seq_printf(m, "# BSSID CHAN SIGNAL NOISE RATE SSID FLAGS\n");
                return 0;
        }

        if (!sta->ap)
                return 0;

        seq_printf(m, "%pM %d %d %d %d '",
                   sta->addr,
                   sta->u.ap.channel, sta->last_rx_signal,
                   sta->last_rx_silence, sta->last_rx_rate);

        for (i = 0; i < sta->u.ap.ssid_len; i++) {
                if (sta->u.ap.ssid[i] >= 32 && sta->u.ap.ssid[i] < 127)
                        seq_putc(m, sta->u.ap.ssid[i]);
                else
                        seq_printf(m, "<%02x>", sta->u.ap.ssid[i]);
        }

        seq_putc(m, '\'');
        if (sta->capability & WLAN_CAPABILITY_ESS)
                seq_puts(m, " [ESS]");
        if (sta->capability & WLAN_CAPABILITY_IBSS)
                seq_puts(m, " [IBSS]");
        if (sta->capability & WLAN_CAPABILITY_PRIVACY)
                seq_puts(m, " [WEP]");
        seq_putc(m, '\n');
        return 0;
}

static void *prism2_ap_proc_start(struct seq_file *m, loff_t *_pos)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        spin_lock_bh(&ap->sta_table_lock);
        return seq_list_start_head(&ap->sta_list, *_pos);
}

static void *prism2_ap_proc_next(struct seq_file *m, void *v, loff_t *_pos)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        return seq_list_next(v, &ap->sta_list, _pos);
}

static void prism2_ap_proc_stop(struct seq_file *m, void *v)
{
        struct ap_data *ap = PDE_DATA(file_inode(m->file));
        spin_unlock_bh(&ap->sta_table_lock);
}

static const struct seq_operations prism2_ap_proc_seqops = {
        .start  = prism2_ap_proc_start,
        .next   = prism2_ap_proc_next,
        .stop   = prism2_ap_proc_stop,
        .show   = prism2_ap_proc_show,
};
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


void hostap_check_sta_fw_version(struct ap_data *ap, int sta_fw_ver)
{
        if (!ap)
                return;

        if (sta_fw_ver == PRISM2_FW_VER(0,8,0)) {
                PDEBUG(DEBUG_AP, "Using data::nullfunc ACK workaround - "
                       "firmware upgrade recommended\n");
                ap->nullfunc_ack = 1;
        } else
                ap->nullfunc_ack = 0;

        if (sta_fw_ver == PRISM2_FW_VER(1,4,2)) {
                printk(KERN_WARNING "%s: Warning: secondary station firmware "
                       "version 1.4.2 does not seem to work in Host AP mode\n",
                       ap->local->dev->name);
        }
}


/* Called only as a tasklet (software IRQ) */
static void hostap_ap_tx_cb(struct sk_buff *skb, int ok, void *data)
{
        struct ap_data *ap = data;
        struct ieee80211_hdr *hdr;

        if (!ap->local->hostapd || !ap->local->apdev) {
                dev_kfree_skb(skb);
                return;
        }

        /* Pass the TX callback frame to the hostapd; use 802.11 header version
         * 1 to indicate failure (no ACK) and 2 success (frame ACKed) */

        hdr = (struct ieee80211_hdr *) skb->data;
        hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_VERS);
        hdr->frame_control |= cpu_to_le16(ok ? BIT(1) : BIT(0));

        skb->dev = ap->local->apdev;
        skb_pull(skb, hostap_80211_get_hdrlen(hdr->frame_control));
        skb->pkt_type = PACKET_OTHERHOST;
        skb->protocol = cpu_to_be16(ETH_P_802_2);
        memset(skb->cb, 0, sizeof(skb->cb));
        netif_rx(skb);
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
/* Called only as a tasklet (software IRQ) */
static void hostap_ap_tx_cb_auth(struct sk_buff *skb, int ok, void *data)
{
        struct ap_data *ap = data;
        struct net_device *dev = ap->local->dev;
        struct ieee80211_hdr *hdr;
        u16 auth_alg, auth_transaction, status;
        __le16 *pos;
        struct sta_info *sta = NULL;
        char *txt = NULL;

        if (ap->local->hostapd) {
                dev_kfree_skb(skb);
                return;
        }

        hdr = (struct ieee80211_hdr *) skb->data;
        if (!ieee80211_is_auth(hdr->frame_control) ||
            skb->len < IEEE80211_MGMT_HDR_LEN + 6) {
                printk(KERN_DEBUG "%s: hostap_ap_tx_cb_auth received invalid "
                       "frame\n", dev->name);
                dev_kfree_skb(skb);
                return;
        }

        pos = (__le16 *) (skb->data + IEEE80211_MGMT_HDR_LEN);
        auth_alg = le16_to_cpu(*pos++);
        auth_transaction = le16_to_cpu(*pos++);
        status = le16_to_cpu(*pos++);

        if (!ok) {
                txt = "frame was not ACKed";
                goto done;
        }

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, hdr->addr1);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&ap->sta_table_lock);

        if (!sta) {
                txt = "STA not found";
                goto done;
        }

        if (status == WLAN_STATUS_SUCCESS &&
            ((auth_alg == WLAN_AUTH_OPEN && auth_transaction == 2) ||
             (auth_alg == WLAN_AUTH_SHARED_KEY && auth_transaction == 4))) {
                txt = "STA authenticated";
                sta->flags |= WLAN_STA_AUTH;
                sta->last_auth = jiffies;
        } else if (status != WLAN_STATUS_SUCCESS)
                txt = "authentication failed";

 done:
        if (sta)
                atomic_dec(&sta->users);
        if (txt) {
                PDEBUG(DEBUG_AP, "%s: %pM auth_cb - alg=%d "
                       "trans#=%d status=%d - %s\n",
                       dev->name, hdr->addr1,
                       auth_alg, auth_transaction, status, txt);
        }
        dev_kfree_skb(skb);
}


/* Called only as a tasklet (software IRQ) */
static void hostap_ap_tx_cb_assoc(struct sk_buff *skb, int ok, void *data)
{
        struct ap_data *ap = data;
        struct net_device *dev = ap->local->dev;
        struct ieee80211_hdr *hdr;
        u16 status;
        __le16 *pos;
        struct sta_info *sta = NULL;
        char *txt = NULL;

        if (ap->local->hostapd) {
                dev_kfree_skb(skb);
                return;
        }

        hdr = (struct ieee80211_hdr *) skb->data;
        if ((!ieee80211_is_assoc_resp(hdr->frame_control) &&
             !ieee80211_is_reassoc_resp(hdr->frame_control)) ||
            skb->len < IEEE80211_MGMT_HDR_LEN + 4) {
                printk(KERN_DEBUG "%s: hostap_ap_tx_cb_assoc received invalid "
                       "frame\n", dev->name);
                dev_kfree_skb(skb);
                return;
        }

        if (!ok) {
                txt = "frame was not ACKed";
                goto done;
        }

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, hdr->addr1);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&ap->sta_table_lock);

        if (!sta) {
                txt = "STA not found";
                goto done;
        }

        pos = (__le16 *) (skb->data + IEEE80211_MGMT_HDR_LEN);
        pos++;
        status = le16_to_cpu(*pos++);
        if (status == WLAN_STATUS_SUCCESS) {
                if (!(sta->flags & WLAN_STA_ASSOC))
                        hostap_event_new_sta(dev, sta);
                txt = "STA associated";
                sta->flags |= WLAN_STA_ASSOC;
                sta->last_assoc = jiffies;
        } else
                txt = "association failed";

 done:
        if (sta)
                atomic_dec(&sta->users);
        if (txt) {
                PDEBUG(DEBUG_AP, "%s: %pM assoc_cb - %s\n",
                       dev->name, hdr->addr1, txt);
        }
        dev_kfree_skb(skb);
}

/* Called only as a tasklet (software IRQ); TX callback for poll frames used
 * in verifying whether the STA is still present. */
static void hostap_ap_tx_cb_poll(struct sk_buff *skb, int ok, void *data)
{
        struct ap_data *ap = data;
        struct ieee80211_hdr *hdr;
        struct sta_info *sta;

        if (skb->len < 24)
                goto fail;
        hdr = (struct ieee80211_hdr *) skb->data;
        if (ok) {
                spin_lock(&ap->sta_table_lock);
                sta = ap_get_sta(ap, hdr->addr1);
                if (sta)
                        sta->flags &= ~WLAN_STA_PENDING_POLL;
                spin_unlock(&ap->sta_table_lock);
        } else {
                PDEBUG(DEBUG_AP,
                       "%s: STA %pM did not ACK activity poll frame\n",
                       ap->local->dev->name, hdr->addr1);
        }

 fail:
        dev_kfree_skb(skb);
}
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


void hostap_init_data(local_info_t *local)
{
        struct ap_data *ap = local->ap;

        if (ap == NULL) {
                printk(KERN_WARNING "hostap_init_data: ap == NULL\n");
                return;
        }
        memset(ap, 0, sizeof(struct ap_data));
        ap->local = local;

        ap->ap_policy = GET_INT_PARM(other_ap_policy, local->card_idx);
        ap->bridge_packets = GET_INT_PARM(ap_bridge_packets, local->card_idx);
        ap->max_inactivity =
                GET_INT_PARM(ap_max_inactivity, local->card_idx) * HZ;
        ap->autom_ap_wds = GET_INT_PARM(autom_ap_wds, local->card_idx);

        spin_lock_init(&ap->sta_table_lock);
        INIT_LIST_HEAD(&ap->sta_list);

        /* Initialize task queue structure for AP management */
        INIT_WORK(&local->ap->add_sta_proc_queue, handle_add_proc_queue);

        ap->tx_callback_idx =
                hostap_tx_callback_register(local, hostap_ap_tx_cb, ap);
        if (ap->tx_callback_idx == 0)
                printk(KERN_WARNING "%s: failed to register TX callback for "
                       "AP\n", local->dev->name);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        INIT_WORK(&local->ap->wds_oper_queue, handle_wds_oper_queue);

        ap->tx_callback_auth =
                hostap_tx_callback_register(local, hostap_ap_tx_cb_auth, ap);
        ap->tx_callback_assoc =
                hostap_tx_callback_register(local, hostap_ap_tx_cb_assoc, ap);
        ap->tx_callback_poll =
                hostap_tx_callback_register(local, hostap_ap_tx_cb_poll, ap);
        if (ap->tx_callback_auth == 0 || ap->tx_callback_assoc == 0 ||
                ap->tx_callback_poll == 0)
                printk(KERN_WARNING "%s: failed to register TX callback for "
                       "AP\n", local->dev->name);

        spin_lock_init(&ap->mac_restrictions.lock);
        INIT_LIST_HEAD(&ap->mac_restrictions.mac_list);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        ap->initialized = 1;
}


void hostap_init_ap_proc(local_info_t *local)
{
        struct ap_data *ap = local->ap;

        ap->proc = local->proc;
        if (ap->proc == NULL)
                return;

#ifndef PRISM2_NO_PROCFS_DEBUG
        proc_create_single_data("ap_debug", 0, ap->proc, ap_debug_proc_show, ap);
#endif /* PRISM2_NO_PROCFS_DEBUG */

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        proc_create_seq_data("ap_control", 0, ap->proc, &ap_control_proc_seqops,
                        ap);
        proc_create_seq_data("ap", 0, ap->proc, &prism2_ap_proc_seqops, ap);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

}


void hostap_free_data(struct ap_data *ap)
{
        struct sta_info *n, *sta;

        if (ap == NULL || !ap->initialized) {
                printk(KERN_DEBUG "hostap_free_data: ap has not yet been "
                       "initialized - skip resource freeing\n");
                return;
        }

        flush_work(&ap->add_sta_proc_queue);

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        flush_work(&ap->wds_oper_queue);
        if (ap->crypt)
                ap->crypt->deinit(ap->crypt_priv);
        ap->crypt = ap->crypt_priv = NULL;
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        list_for_each_entry_safe(sta, n, &ap->sta_list, list) {
                ap_sta_hash_del(ap, sta);
                list_del(&sta->list);
                if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap && sta->local)
                        hostap_event_expired_sta(sta->local->dev, sta);
                ap_free_sta(ap, sta);
        }

#ifndef PRISM2_NO_PROCFS_DEBUG
        if (ap->proc != NULL) {
                remove_proc_entry("ap_debug", ap->proc);
        }
#endif /* PRISM2_NO_PROCFS_DEBUG */

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        if (ap->proc != NULL) {
          remove_proc_entry("ap", ap->proc);
                remove_proc_entry("ap_control", ap->proc);
        }
        ap_control_flush_macs(&ap->mac_restrictions);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        ap->initialized = 0;
}


/* caller should have mutex for AP STA list handling */
static struct sta_info* ap_get_sta(struct ap_data *ap, u8 *sta)
{
        struct sta_info *s;

        s = ap->sta_hash[STA_HASH(sta)];
        while (s != NULL && !ether_addr_equal(s->addr, sta))
                s = s->hnext;
        return s;
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT

/* Called from timer handler and from scheduled AP queue handlers */
static void prism2_send_mgmt(struct net_device *dev,
                             u16 type_subtype, char *body,
                             int body_len, u8 *addr, u16 tx_cb_idx)
{
        struct hostap_interface *iface;
        local_info_t *local;
        struct ieee80211_hdr *hdr;
        u16 fc;
        struct sk_buff *skb;
        struct hostap_skb_tx_data *meta;
        int hdrlen;

        iface = netdev_priv(dev);
        local = iface->local;
        dev = local->dev; /* always use master radio device */
        iface = netdev_priv(dev);

        if (!(dev->flags & IFF_UP)) {
                PDEBUG(DEBUG_AP, "%s: prism2_send_mgmt - device is not UP - "
                       "cannot send frame\n", dev->name);
                return;
        }

        skb = dev_alloc_skb(sizeof(*hdr) + body_len);
        if (skb == NULL) {
                PDEBUG(DEBUG_AP, "%s: prism2_send_mgmt failed to allocate "
                       "skb\n", dev->name);
                return;
        }

        fc = type_subtype;
        hdrlen = hostap_80211_get_hdrlen(cpu_to_le16(type_subtype));
        hdr = skb_put_zero(skb, hdrlen);
        if (body)
                skb_put_data(skb, body, body_len);

        /* FIX: ctrl::ack sending used special HFA384X_TX_CTRL_802_11
         * tx_control instead of using local->tx_control */


        memcpy(hdr->addr1, addr, ETH_ALEN); /* DA / RA */
        if (ieee80211_is_data(hdr->frame_control)) {
                fc |= IEEE80211_FCTL_FROMDS;
                memcpy(hdr->addr2, dev->dev_addr, ETH_ALEN); /* BSSID */
                memcpy(hdr->addr3, dev->dev_addr, ETH_ALEN); /* SA */
        } else if (ieee80211_is_ctl(hdr->frame_control)) {
                /* control:ACK does not have addr2 or addr3 */
                eth_zero_addr(hdr->addr2);
                eth_zero_addr(hdr->addr3);
        } else {
                memcpy(hdr->addr2, dev->dev_addr, ETH_ALEN); /* SA */
                memcpy(hdr->addr3, dev->dev_addr, ETH_ALEN); /* BSSID */
        }

        hdr->frame_control = cpu_to_le16(fc);

        meta = (struct hostap_skb_tx_data *) skb->cb;
        memset(meta, 0, sizeof(*meta));
        meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
        meta->iface = iface;
        meta->tx_cb_idx = tx_cb_idx;

        skb->dev = dev;
        skb_reset_mac_header(skb);
        skb_reset_network_header(skb);
        dev_queue_xmit(skb);
}
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

#ifdef CONFIG_PROC_FS
static int prism2_sta_proc_show(struct seq_file *m, void *v)
{
        struct sta_info *sta = m->private;
        int i;

        /* FIX: possible race condition.. the STA data could have just expired,
         * but proc entry was still here so that the read could have started;
         * some locking should be done here.. */

        seq_printf(m,
                   "%s=%pM\nusers=%d\naid=%d\n"
                   "flags=0x%04x%s%s%s%s%s%s%s\n"
                   "capability=0x%02x\nlisten_interval=%d\nsupported_rates=",
                   sta->ap ? "AP" : "STA",
                   sta->addr, atomic_read(&sta->users), sta->aid,
                   sta->flags,
                   sta->flags & WLAN_STA_AUTH ? " AUTH" : "",
                   sta->flags & WLAN_STA_ASSOC ? " ASSOC" : "",
                   sta->flags & WLAN_STA_PS ? " PS" : "",
                   sta->flags & WLAN_STA_TIM ? " TIM" : "",
                   sta->flags & WLAN_STA_PERM ? " PERM" : "",
                   sta->flags & WLAN_STA_AUTHORIZED ? " AUTHORIZED" : "",
                   sta->flags & WLAN_STA_PENDING_POLL ? " POLL" : "",
                   sta->capability, sta->listen_interval);
        /* supported_rates: 500 kbit/s units with msb ignored */
        for (i = 0; i < sizeof(sta->supported_rates); i++)
                if (sta->supported_rates[i] != 0)
                        seq_printf(m, "%d%sMbps ",
                                   (sta->supported_rates[i] & 0x7f) / 2,
                                   sta->supported_rates[i] & 1 ? ".5" : "");
        seq_printf(m,
                   "\njiffies=%lu\nlast_auth=%lu\nlast_assoc=%lu\n"
                   "last_rx=%lu\nlast_tx=%lu\nrx_packets=%lu\n"
                   "tx_packets=%lu\n"
                   "rx_bytes=%lu\ntx_bytes=%lu\nbuffer_count=%d\n"
                   "last_rx: silence=%d dBm signal=%d dBm rate=%d%s Mbps\n"
                   "tx_rate=%d\ntx[1M]=%d\ntx[2M]=%d\ntx[5.5M]=%d\n"
                   "tx[11M]=%d\n"
                   "rx[1M]=%d\nrx[2M]=%d\nrx[5.5M]=%d\nrx[11M]=%d\n",
                   jiffies, sta->last_auth, sta->last_assoc, sta->last_rx,
                   sta->last_tx,
                   sta->rx_packets, sta->tx_packets, sta->rx_bytes,
                   sta->tx_bytes, skb_queue_len(&sta->tx_buf),
                   sta->last_rx_silence,
                   sta->last_rx_signal, sta->last_rx_rate / 10,
                   sta->last_rx_rate % 10 ? ".5" : "",
                   sta->tx_rate, sta->tx_count[0], sta->tx_count[1],
                   sta->tx_count[2], sta->tx_count[3],  sta->rx_count[0],
                   sta->rx_count[1], sta->rx_count[2], sta->rx_count[3]);
        if (sta->crypt && sta->crypt->ops && sta->crypt->ops->print_stats)
                sta->crypt->ops->print_stats(m, sta->crypt->priv);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        if (sta->ap) {
                if (sta->u.ap.channel >= 0)
                        seq_printf(m, "channel=%d\n", sta->u.ap.channel);
                seq_puts(m, "ssid=");
                for (i = 0; i < sta->u.ap.ssid_len; i++) {
                        if (sta->u.ap.ssid[i] >= 32 && sta->u.ap.ssid[i] < 127)
                                seq_putc(m, sta->u.ap.ssid[i]);
                        else
                                seq_printf(m, "<%02x>", sta->u.ap.ssid[i]);
                }
                seq_putc(m, '\n');
        }
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        return 0;
}
#endif

static void handle_add_proc_queue(struct work_struct *work)
{
        struct ap_data *ap = container_of(work, struct ap_data,
                                          add_sta_proc_queue);
        struct sta_info *sta;
        char name[20];
        struct add_sta_proc_data *entry, *prev;

        entry = ap->add_sta_proc_entries;
        ap->add_sta_proc_entries = NULL;

        while (entry) {
                spin_lock_bh(&ap->sta_table_lock);
                sta = ap_get_sta(ap, entry->addr);
                if (sta)
                        atomic_inc(&sta->users);
                spin_unlock_bh(&ap->sta_table_lock);

                if (sta) {
                        sprintf(name, "%pM", sta->addr);
                        sta->proc = proc_create_single_data(
                                name, 0, ap->proc,
                                prism2_sta_proc_show, sta);

                        atomic_dec(&sta->users);
                }

                prev = entry;
                entry = entry->next;
                kfree(prev);
        }
}


static struct sta_info * ap_add_sta(struct ap_data *ap, u8 *addr)
{
        struct sta_info *sta;

        sta = kzalloc(sizeof(struct sta_info), GFP_ATOMIC);
        if (sta == NULL) {
                PDEBUG(DEBUG_AP, "AP: kmalloc failed\n");
                return NULL;
        }

        /* initialize STA info data */
        sta->local = ap->local;
        skb_queue_head_init(&sta->tx_buf);
        memcpy(sta->addr, addr, ETH_ALEN);

        atomic_inc(&sta->users);
        spin_lock_bh(&ap->sta_table_lock);
        list_add(&sta->list, &ap->sta_list);
        ap->num_sta++;
        ap_sta_hash_add(ap, sta);
        spin_unlock_bh(&ap->sta_table_lock);

        if (ap->proc) {
                struct add_sta_proc_data *entry;
                /* schedule a non-interrupt context process to add a procfs
                 * entry for the STA since procfs code use GFP_KERNEL */
                entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
                if (entry) {
                        memcpy(entry->addr, sta->addr, ETH_ALEN);
                        entry->next = ap->add_sta_proc_entries;
                        ap->add_sta_proc_entries = entry;
                        schedule_work(&ap->add_sta_proc_queue);
                } else
                        printk(KERN_DEBUG "Failed to add STA proc data\n");
        }

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        timer_setup(&sta->timer, ap_handle_timer, 0);
        sta->timer.expires = jiffies + ap->max_inactivity;
        if (!ap->local->hostapd)
                add_timer(&sta->timer);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        return sta;
}


static int ap_tx_rate_ok(int rateidx, struct sta_info *sta,
                         local_info_t *local)
{
        if (rateidx > sta->tx_max_rate ||
            !(sta->tx_supp_rates & (1 << rateidx)))
                return 0;

        if (local->tx_rate_control != 0 &&
            !(local->tx_rate_control & (1 << rateidx)))
                return 0;

        return 1;
}


static void prism2_check_tx_rates(struct sta_info *sta)
{
        int i;

        sta->tx_supp_rates = 0;
        for (i = 0; i < sizeof(sta->supported_rates); i++) {
                if ((sta->supported_rates[i] & 0x7f) == 2)
                        sta->tx_supp_rates |= WLAN_RATE_1M;
                if ((sta->supported_rates[i] & 0x7f) == 4)
                        sta->tx_supp_rates |= WLAN_RATE_2M;
                if ((sta->supported_rates[i] & 0x7f) == 11)
                        sta->tx_supp_rates |= WLAN_RATE_5M5;
                if ((sta->supported_rates[i] & 0x7f) == 22)
                        sta->tx_supp_rates |= WLAN_RATE_11M;
        }
        sta->tx_max_rate = sta->tx_rate = sta->tx_rate_idx = 0;
        if (sta->tx_supp_rates & WLAN_RATE_1M) {
                sta->tx_max_rate = 0;
                if (ap_tx_rate_ok(0, sta, sta->local)) {
                        sta->tx_rate = 10;
                        sta->tx_rate_idx = 0;
                }
        }
        if (sta->tx_supp_rates & WLAN_RATE_2M) {
                sta->tx_max_rate = 1;
                if (ap_tx_rate_ok(1, sta, sta->local)) {
                        sta->tx_rate = 20;
                        sta->tx_rate_idx = 1;
                }
        }
        if (sta->tx_supp_rates & WLAN_RATE_5M5) {
                sta->tx_max_rate = 2;
                if (ap_tx_rate_ok(2, sta, sta->local)) {
                        sta->tx_rate = 55;
                        sta->tx_rate_idx = 2;
                }
        }
        if (sta->tx_supp_rates & WLAN_RATE_11M) {
                sta->tx_max_rate = 3;
                if (ap_tx_rate_ok(3, sta, sta->local)) {
                        sta->tx_rate = 110;
                        sta->tx_rate_idx = 3;
                }
        }
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT

static void ap_crypt_init(struct ap_data *ap)
{
        ap->crypt = lib80211_get_crypto_ops("WEP");

        if (ap->crypt) {
                if (ap->crypt->init) {
                        ap->crypt_priv = ap->crypt->init(0);
                        if (ap->crypt_priv == NULL)
                                ap->crypt = NULL;
                        else {
                                u8 key[WEP_KEY_LEN];
                                get_random_bytes(key, WEP_KEY_LEN);
                                ap->crypt->set_key(key, WEP_KEY_LEN, NULL,
                                                   ap->crypt_priv);
                        }
                }
        }

        if (ap->crypt == NULL) {
                printk(KERN_WARNING "AP could not initialize WEP: load module "
                       "lib80211_crypt_wep.ko\n");
        }
}


/* Generate challenge data for shared key authentication. IEEE 802.11 specifies
 * that WEP algorithm is used for generating challenge. This should be unique,
 * but otherwise there is not really need for randomness etc. Initialize WEP
 * with pseudo random key and then use increasing IV to get unique challenge
 * streams.
 *
 * Called only as a scheduled task for pending AP frames.
 */
static char * ap_auth_make_challenge(struct ap_data *ap)
{
        char *tmpbuf;
        struct sk_buff *skb;

        if (ap->crypt == NULL) {
                ap_crypt_init(ap);
                if (ap->crypt == NULL)
                        return NULL;
        }

        tmpbuf = kmalloc(WLAN_AUTH_CHALLENGE_LEN, GFP_ATOMIC);
        if (tmpbuf == NULL) {
                PDEBUG(DEBUG_AP, "AP: kmalloc failed for challenge\n");
                return NULL;
        }

        skb = dev_alloc_skb(WLAN_AUTH_CHALLENGE_LEN +
                            ap->crypt->extra_mpdu_prefix_len +
                            ap->crypt->extra_mpdu_postfix_len);
        if (skb == NULL) {
                kfree(tmpbuf);
                return NULL;
        }

        skb_reserve(skb, ap->crypt->extra_mpdu_prefix_len);
        skb_put_zero(skb, WLAN_AUTH_CHALLENGE_LEN);
        if (ap->crypt->encrypt_mpdu(skb, 0, ap->crypt_priv)) {
                dev_kfree_skb(skb);
                kfree(tmpbuf);
                return NULL;
        }

        skb_copy_from_linear_data_offset(skb, ap->crypt->extra_mpdu_prefix_len,
                                         tmpbuf, WLAN_AUTH_CHALLENGE_LEN);
        dev_kfree_skb(skb);

        return tmpbuf;
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_authen(local_info_t *local, struct sk_buff *skb,
                          struct hostap_80211_rx_status *rx_stats)
{
        struct net_device *dev = local->dev;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        size_t hdrlen;
        struct ap_data *ap = local->ap;
        char body[8 + WLAN_AUTH_CHALLENGE_LEN], *challenge = NULL;
        int len, olen;
        u16 auth_alg, auth_transaction, status_code;
        __le16 *pos;
        u16 resp = WLAN_STATUS_SUCCESS;
        struct sta_info *sta = NULL;
        struct lib80211_crypt_data *crypt;
        char *txt = "";

        len = skb->len - IEEE80211_MGMT_HDR_LEN;

        hdrlen = hostap_80211_get_hdrlen(hdr->frame_control);

        if (len < 6) {
                PDEBUG(DEBUG_AP, "%s: handle_authen - too short payload "
                       "(len=%d) from %pM\n", dev->name, len, hdr->addr2);
                return;
        }

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&local->ap->sta_table_lock);

        if (sta && sta->crypt)
                crypt = sta->crypt;
        else {
                int idx = 0;
                if (skb->len >= hdrlen + 3)
                        idx = skb->data[hdrlen + 3] >> 6;
                crypt = local->crypt_info.crypt[idx];
        }

        pos = (__le16 *) (skb->data + IEEE80211_MGMT_HDR_LEN);
        auth_alg = __le16_to_cpu(*pos);
        pos++;
        auth_transaction = __le16_to_cpu(*pos);
        pos++;
        status_code = __le16_to_cpu(*pos);
        pos++;

        if (ether_addr_equal(dev->dev_addr, hdr->addr2) ||
            ap_control_mac_deny(&ap->mac_restrictions, hdr->addr2)) {
                txt = "authentication denied";
                resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                goto fail;
        }

        if (((local->auth_algs & PRISM2_AUTH_OPEN) &&
             auth_alg == WLAN_AUTH_OPEN) ||
            ((local->auth_algs & PRISM2_AUTH_SHARED_KEY) &&
             crypt && auth_alg == WLAN_AUTH_SHARED_KEY)) {
        } else {
                txt = "unsupported algorithm";
                resp = WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG;
                goto fail;
        }

        if (len >= 8) {
                u8 *u = (u8 *) pos;
                if (*u == WLAN_EID_CHALLENGE) {
                        if (*(u + 1) != WLAN_AUTH_CHALLENGE_LEN) {
                                txt = "invalid challenge len";
                                resp = WLAN_STATUS_CHALLENGE_FAIL;
                                goto fail;
                        }
                        if (len - 8 < WLAN_AUTH_CHALLENGE_LEN) {
                                txt = "challenge underflow";
                                resp = WLAN_STATUS_CHALLENGE_FAIL;
                                goto fail;
                        }
                        challenge = (char *) (u + 2);
                }
        }

        if (sta && sta->ap) {
                if (time_after(jiffies, sta->u.ap.last_beacon +
                               (10 * sta->listen_interval * HZ) / 1024)) {
                        PDEBUG(DEBUG_AP, "%s: no beacons received for a while,"
                               " assuming AP %pM is now STA\n",
                               dev->name, sta->addr);
                        sta->ap = 0;
                        sta->flags = 0;
                        sta->u.sta.challenge = NULL;
                } else {
                        txt = "AP trying to authenticate?";
                        resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                        goto fail;
                }
        }

        if ((auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1) ||
            (auth_alg == WLAN_AUTH_SHARED_KEY &&
             (auth_transaction == 1 ||
              (auth_transaction == 3 && sta != NULL &&
               sta->u.sta.challenge != NULL)))) {
        } else {
                txt = "unknown authentication transaction number";
                resp = WLAN_STATUS_UNKNOWN_AUTH_TRANSACTION;
                goto fail;
        }

        if (sta == NULL) {
                txt = "new STA";

                if (local->ap->num_sta >= MAX_STA_COUNT) {
                        /* FIX: might try to remove some old STAs first? */
                        txt = "no more room for new STAs";
                        resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                        goto fail;
                }

                sta = ap_add_sta(local->ap, hdr->addr2);
                if (sta == NULL) {
                        txt = "ap_add_sta failed";
                        resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                        goto fail;
                }
        }

        switch (auth_alg) {
        case WLAN_AUTH_OPEN:
                txt = "authOK";
                /* IEEE 802.11 standard is not completely clear about
                 * whether STA is considered authenticated after
                 * authentication OK frame has been send or after it
                 * has been ACKed. In order to reduce interoperability
                 * issues, mark the STA authenticated before ACK. */
                sta->flags |= WLAN_STA_AUTH;
                break;

        case WLAN_AUTH_SHARED_KEY:
                if (auth_transaction == 1) {
                        if (sta->u.sta.challenge == NULL) {
                                sta->u.sta.challenge =
                                        ap_auth_make_challenge(local->ap);
                                if (sta->u.sta.challenge == NULL) {
                                        resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                                        goto fail;
                                }
                        }
                } else {
                        if (sta->u.sta.challenge == NULL ||
                            challenge == NULL ||
                            memcmp(sta->u.sta.challenge, challenge,
                                   WLAN_AUTH_CHALLENGE_LEN) != 0 ||
                            !ieee80211_has_protected(hdr->frame_control)) {
                                txt = "challenge response incorrect";
                                resp = WLAN_STATUS_CHALLENGE_FAIL;
                                goto fail;
                        }

                        txt = "challenge OK - authOK";
                        /* IEEE 802.11 standard is not completely clear about
                         * whether STA is considered authenticated after
                         * authentication OK frame has been send or after it
                         * has been ACKed. In order to reduce interoperability
                         * issues, mark the STA authenticated before ACK. */
                        sta->flags |= WLAN_STA_AUTH;
                        kfree(sta->u.sta.challenge);
                        sta->u.sta.challenge = NULL;
                }
                break;
        }

 fail:
        pos = (__le16 *) body;
        *pos = cpu_to_le16(auth_alg);
        pos++;
        *pos = cpu_to_le16(auth_transaction + 1);
        pos++;
        *pos = cpu_to_le16(resp); /* status_code */
        pos++;
        olen = 6;

        if (resp == WLAN_STATUS_SUCCESS && sta != NULL &&
            sta->u.sta.challenge != NULL &&
            auth_alg == WLAN_AUTH_SHARED_KEY && auth_transaction == 1) {
                u8 *tmp = (u8 *) pos;
                *tmp++ = WLAN_EID_CHALLENGE;
                *tmp++ = WLAN_AUTH_CHALLENGE_LEN;
                pos++;
                memcpy(pos, sta->u.sta.challenge, WLAN_AUTH_CHALLENGE_LEN);
                olen += 2 + WLAN_AUTH_CHALLENGE_LEN;
        }

        prism2_send_mgmt(dev, IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_AUTH,
                         body, olen, hdr->addr2, ap->tx_callback_auth);

        if (sta) {
                sta->last_rx = jiffies;
                atomic_dec(&sta->users);
        }

        if (resp) {
                PDEBUG(DEBUG_AP, "%s: %pM auth (alg=%d "
                       "trans#=%d stat=%d len=%d fc=%04x) ==> %d (%s)\n",
                       dev->name, hdr->addr2,
                       auth_alg, auth_transaction, status_code, len,
                       le16_to_cpu(hdr->frame_control), resp, txt);
        }
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_assoc(local_info_t *local, struct sk_buff *skb,
                         struct hostap_80211_rx_status *rx_stats, int reassoc)
{
        struct net_device *dev = local->dev;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        char body[12], *p, *lpos;
        int len, left;
        __le16 *pos;
        u16 resp = WLAN_STATUS_SUCCESS;
        struct sta_info *sta = NULL;
        int send_deauth = 0;
        char __always_unused *txt = "";
        u8 prev_ap[ETH_ALEN];

        left = len = skb->len - IEEE80211_MGMT_HDR_LEN;

        if (len < (reassoc ? 10 : 4)) {
                PDEBUG(DEBUG_AP, "%s: handle_assoc - too short payload "
                       "(len=%d, reassoc=%d) from %pM\n",
                       dev->name, len, reassoc, hdr->addr2);
                return;
        }

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta == NULL || (sta->flags & WLAN_STA_AUTH) == 0) {
                spin_unlock_bh(&local->ap->sta_table_lock);
                txt = "trying to associate before authentication";
                send_deauth = 1;
                resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                sta = NULL; /* do not decrement sta->users */
                goto fail;
        }
        atomic_inc(&sta->users);
        spin_unlock_bh(&local->ap->sta_table_lock);

        pos = (__le16 *) (skb->data + IEEE80211_MGMT_HDR_LEN);
        sta->capability = __le16_to_cpu(*pos);
        pos++; left -= 2;
        sta->listen_interval = __le16_to_cpu(*pos);
        pos++; left -= 2;

        if (reassoc) {
                memcpy(prev_ap, pos, ETH_ALEN);
                pos++; pos++; pos++; left -= 6;
        } else
                eth_zero_addr(prev_ap);

        if (left >= 2) {
                unsigned int ileft;
                unsigned char *u = (unsigned char *) pos;

                if (*u == WLAN_EID_SSID) {
                        u++; left--;
                        ileft = *u;
                        u++; left--;

                        if (ileft > left || ileft > MAX_SSID_LEN) {
                                txt = "SSID overflow";
                                resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                                goto fail;
                        }

                        if (ileft != strlen(local->essid) ||
                            memcmp(local->essid, u, ileft) != 0) {
                                txt = "not our SSID";
                                resp = WLAN_STATUS_ASSOC_DENIED_UNSPEC;
                                goto fail;
                        }

                        u += ileft;
                        left -= ileft;
                }

                if (left >= 2 && *u == WLAN_EID_SUPP_RATES) {
                        u++; left--;
                        ileft = *u;
                        u++; left--;

                        if (ileft > left || ileft == 0 ||
                            ileft > WLAN_SUPP_RATES_MAX) {
                                txt = "SUPP_RATES len error";
                                resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                                goto fail;
                        }

                        memset(sta->supported_rates, 0,
                               sizeof(sta->supported_rates));
                        memcpy(sta->supported_rates, u, ileft);
                        prism2_check_tx_rates(sta);

                        u += ileft;
                        left -= ileft;
                }

                if (left > 0) {
                        PDEBUG(DEBUG_AP, "%s: assoc from %pM"
                               " with extra data (%d bytes) [",
                               dev->name, hdr->addr2, left);
                        while (left > 0) {
                                PDEBUG2(DEBUG_AP, "<%02x>", *u);
                                u++; left--;
                        }
                        PDEBUG2(DEBUG_AP, "]\n");
                }
        } else {
                txt = "frame underflow";
                resp = WLAN_STATUS_UNSPECIFIED_FAILURE;
                goto fail;
        }

        /* get a unique AID */
        if (sta->aid > 0)
                txt = "OK, old AID";
        else {
                spin_lock_bh(&local->ap->sta_table_lock);
                for (sta->aid = 1; sta->aid <= MAX_AID_TABLE_SIZE; sta->aid++)
                        if (local->ap->sta_aid[sta->aid - 1] == NULL)
                                break;
                if (sta->aid > MAX_AID_TABLE_SIZE) {
                        sta->aid = 0;
                        spin_unlock_bh(&local->ap->sta_table_lock);
                        resp = WLAN_STATUS_AP_UNABLE_TO_HANDLE_NEW_STA;
                        txt = "no room for more AIDs";
                } else {
                        local->ap->sta_aid[sta->aid - 1] = sta;
                        spin_unlock_bh(&local->ap->sta_table_lock);
                        txt = "OK, new AID";
                }
        }

 fail:
        pos = (__le16 *) body;

        if (send_deauth) {
                *pos = cpu_to_le16(WLAN_REASON_STA_REQ_ASSOC_WITHOUT_AUTH);
                pos++;
        } else {
                /* FIX: CF-Pollable and CF-PollReq should be set to match the
                 * values in beacons/probe responses */
                /* FIX: how about privacy and WEP? */
                /* capability */
                *pos = cpu_to_le16(WLAN_CAPABILITY_ESS);
                pos++;

                /* status_code */
                *pos = cpu_to_le16(resp);
                pos++;

                *pos = cpu_to_le16((sta && sta->aid > 0 ? sta->aid : 0) |
                                     BIT(14) | BIT(15)); /* AID */
                pos++;

                /* Supported rates (Information element) */
                p = (char *) pos;
                *p++ = WLAN_EID_SUPP_RATES;
                lpos = p;
                *p++ = 0; /* len */
                if (local->tx_rate_control & WLAN_RATE_1M) {
                        *p++ = local->basic_rates & WLAN_RATE_1M ? 0x82 : 0x02;
                        (*lpos)++;
                }
                if (local->tx_rate_control & WLAN_RATE_2M) {
                        *p++ = local->basic_rates & WLAN_RATE_2M ? 0x84 : 0x04;
                        (*lpos)++;
                }
                if (local->tx_rate_control & WLAN_RATE_5M5) {
                        *p++ = local->basic_rates & WLAN_RATE_5M5 ?
                                0x8b : 0x0b;
                        (*lpos)++;
                }
                if (local->tx_rate_control & WLAN_RATE_11M) {
                        *p++ = local->basic_rates & WLAN_RATE_11M ?
                                0x96 : 0x16;
                        (*lpos)++;
                }
                pos = (__le16 *) p;
        }

        prism2_send_mgmt(dev, IEEE80211_FTYPE_MGMT |
                         (send_deauth ? IEEE80211_STYPE_DEAUTH :
                          (reassoc ? IEEE80211_STYPE_REASSOC_RESP :
                           IEEE80211_STYPE_ASSOC_RESP)),
                         body, (u8 *) pos - (u8 *) body,
                         hdr->addr2,
                         send_deauth ? 0 : local->ap->tx_callback_assoc);

        if (sta) {
                if (resp == WLAN_STATUS_SUCCESS) {
                        sta->last_rx = jiffies;
                        /* STA will be marked associated from TX callback, if
                         * AssocResp is ACKed */
                }
                atomic_dec(&sta->users);
        }

#if 0
        PDEBUG(DEBUG_AP, "%s: %pM %sassoc (len=%d "
               "prev_ap=%pM) => %d(%d) (%s)\n",
               dev->name,
               hdr->addr2,
               reassoc ? "re" : "", len,
               prev_ap,
               resp, send_deauth, txt);
#endif
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_deauth(local_info_t *local, struct sk_buff *skb,
                          struct hostap_80211_rx_status *rx_stats)
{
        struct net_device *dev = local->dev;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        char *body = (char *) (skb->data + IEEE80211_MGMT_HDR_LEN);
        int len;
        u16 reason_code;
        __le16 *pos;
        struct sta_info *sta = NULL;

        len = skb->len - IEEE80211_MGMT_HDR_LEN;

        if (len < 2) {
                printk("handle_deauth - too short payload (len=%d)\n", len);
                return;
        }

        pos = (__le16 *) body;
        reason_code = le16_to_cpu(*pos);

        PDEBUG(DEBUG_AP, "%s: deauthentication: %pM len=%d, "
               "reason_code=%d\n", dev->name, hdr->addr2,
               len, reason_code);

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta != NULL) {
                if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap)
                        hostap_event_expired_sta(local->dev, sta);
                sta->flags &= ~(WLAN_STA_AUTH | WLAN_STA_ASSOC);
        }
        spin_unlock_bh(&local->ap->sta_table_lock);
        if (sta == NULL) {
                printk("%s: deauthentication from %pM, "
               "reason_code=%d, but STA not authenticated\n", dev->name,
                       hdr->addr2, reason_code);
        }
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_disassoc(local_info_t *local, struct sk_buff *skb,
                            struct hostap_80211_rx_status *rx_stats)
{
        struct net_device *dev = local->dev;
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        char *body = skb->data + IEEE80211_MGMT_HDR_LEN;
        int len;
        u16 reason_code;
        __le16 *pos;
        struct sta_info *sta = NULL;

        len = skb->len - IEEE80211_MGMT_HDR_LEN;

        if (len < 2) {
                printk("handle_disassoc - too short payload (len=%d)\n", len);
                return;
        }

        pos = (__le16 *) body;
        reason_code = le16_to_cpu(*pos);

        PDEBUG(DEBUG_AP, "%s: disassociation: %pM len=%d, "
               "reason_code=%d\n", dev->name, hdr->addr2,
               len, reason_code);

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta != NULL) {
                if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap)
                        hostap_event_expired_sta(local->dev, sta);
                sta->flags &= ~WLAN_STA_ASSOC;
        }
        spin_unlock_bh(&local->ap->sta_table_lock);
        if (sta == NULL) {
                printk("%s: disassociation from %pM, "
                       "reason_code=%d, but STA not authenticated\n",
                       dev->name, hdr->addr2, reason_code);
        }
}


/* Called only as a scheduled task for pending AP frames. */
static void ap_handle_data_nullfunc(local_info_t *local,
                                    struct ieee80211_hdr *hdr)
{
        struct net_device *dev = local->dev;

        /* some STA f/w's seem to require control::ACK frame for
         * data::nullfunc, but at least Prism2 station f/w version 0.8.0 does
         * not send this..
         * send control::ACK for the data::nullfunc */

        printk(KERN_DEBUG "Sending control::ACK for data::nullfunc\n");
        prism2_send_mgmt(dev, IEEE80211_FTYPE_CTL | IEEE80211_STYPE_ACK,
                         NULL, 0, hdr->addr2, 0);
}


/* Called only as a scheduled task for pending AP frames. */
static void ap_handle_dropped_data(local_info_t *local,
                                   struct ieee80211_hdr *hdr)
{
        struct net_device *dev = local->dev;
        struct sta_info *sta;
        __le16 reason;

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&local->ap->sta_table_lock);

        if (sta != NULL && (sta->flags & WLAN_STA_ASSOC)) {
                PDEBUG(DEBUG_AP, "ap_handle_dropped_data: STA is now okay?\n");
                atomic_dec(&sta->users);
                return;
        }

        reason = cpu_to_le16(WLAN_REASON_CLASS3_FRAME_FROM_NONASSOC_STA);
        prism2_send_mgmt(dev, IEEE80211_FTYPE_MGMT |
                         ((sta == NULL || !(sta->flags & WLAN_STA_ASSOC)) ?
                          IEEE80211_STYPE_DEAUTH : IEEE80211_STYPE_DISASSOC),
                         (char *) &reason, sizeof(reason), hdr->addr2, 0);

        if (sta)
                atomic_dec(&sta->users);
}

#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


/* Called only as a scheduled task for pending AP frames. */
static void pspoll_send_buffered(local_info_t *local, struct sta_info *sta,
                                 struct sk_buff *skb)
{
        struct hostap_skb_tx_data *meta;

        if (!(sta->flags & WLAN_STA_PS)) {
                /* Station has moved to non-PS mode, so send all buffered
                 * frames using normal device queue. */
                dev_queue_xmit(skb);
                return;
        }

        /* add a flag for hostap_handle_sta_tx() to know that this skb should
         * be passed through even though STA is using PS */
        meta = (struct hostap_skb_tx_data *) skb->cb;
        meta->flags |= HOSTAP_TX_FLAGS_BUFFERED_FRAME;
        if (!skb_queue_empty(&sta->tx_buf)) {
                /* indicate to STA that more frames follow */
                meta->flags |= HOSTAP_TX_FLAGS_ADD_MOREDATA;
        }
        dev_queue_xmit(skb);
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_pspoll(local_info_t *local,
                          struct ieee80211_hdr *hdr,
                          struct hostap_80211_rx_status *rx_stats)
{
        struct net_device *dev = local->dev;
        struct sta_info *sta;
        u16 aid;
        struct sk_buff *skb;

        PDEBUG(DEBUG_PS2, "handle_pspoll: BSSID=%pM, TA=%pM PWRMGT=%d\n",
               hdr->addr1, hdr->addr2, !!ieee80211_has_pm(hdr->frame_control));

        if (!ether_addr_equal(hdr->addr1, dev->dev_addr)) {
                PDEBUG(DEBUG_AP,
                       "handle_pspoll - addr1(BSSID)=%pM not own MAC\n",
                       hdr->addr1);
                return;
        }

        aid = le16_to_cpu(hdr->duration_id);
        if ((aid & (BIT(15) | BIT(14))) != (BIT(15) | BIT(14))) {
                PDEBUG(DEBUG_PS, "   PSPOLL and AID[15:14] not set\n");
                return;
        }
        aid &= ~(BIT(15) | BIT(14));
        if (aid == 0 || aid > MAX_AID_TABLE_SIZE) {
                PDEBUG(DEBUG_PS, "   invalid aid=%d\n", aid);
                return;
        }
        PDEBUG(DEBUG_PS2, "   aid=%d\n", aid);

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&local->ap->sta_table_lock);

        if (sta == NULL) {
                PDEBUG(DEBUG_PS, "   STA not found\n");
                return;
        }
        if (sta->aid != aid) {
                PDEBUG(DEBUG_PS, "   received aid=%i does not match with "
                       "assoc.aid=%d\n", aid, sta->aid);
                return;
        }

        /* FIX: todo:
         * - add timeout for buffering (clear aid in TIM vector if buffer timed
         *   out (expiry time must be longer than ListenInterval for
         *   the corresponding STA; "8802-11: 11.2.1.9 AP aging function"
         * - what to do, if buffered, pspolled, and sent frame is not ACKed by
         *   sta; store buffer for later use and leave TIM aid bit set? use
         *   TX event to check whether frame was ACKed?
         */

        while ((skb = skb_dequeue(&sta->tx_buf)) != NULL) {
                /* send buffered frame .. */
                PDEBUG(DEBUG_PS2, "Sending buffered frame to STA after PS POLL"
                       " (buffer_count=%d)\n", skb_queue_len(&sta->tx_buf));

                pspoll_send_buffered(local, sta, skb);

                if (sta->flags & WLAN_STA_PS) {
                        /* send only one buffered packet per PS Poll */
                        /* FIX: should ignore further PS Polls until the
                         * buffered packet that was just sent is acknowledged
                         * (Tx or TxExc event) */
                        break;
                }
        }

        if (skb_queue_empty(&sta->tx_buf)) {
                /* try to clear aid from TIM */
                if (!(sta->flags & WLAN_STA_TIM))
                        PDEBUG(DEBUG_PS2,  "Re-unsetting TIM for aid %d\n",
                               aid);
                hostap_set_tim(local, aid, 0);
                sta->flags &= ~WLAN_STA_TIM;
        }

        atomic_dec(&sta->users);
}


#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT

static void handle_wds_oper_queue(struct work_struct *work)
{
        struct ap_data *ap = container_of(work, struct ap_data,
                                          wds_oper_queue);
        local_info_t *local = ap->local;
        struct wds_oper_data *entry, *prev;

        spin_lock_bh(&local->lock);
        entry = local->ap->wds_oper_entries;
        local->ap->wds_oper_entries = NULL;
        spin_unlock_bh(&local->lock);

        while (entry) {
                PDEBUG(DEBUG_AP, "%s: %s automatic WDS connection "
                       "to AP %pM\n",
                       local->dev->name,
                       entry->type == WDS_ADD ? "adding" : "removing",
                       entry->addr);
                if (entry->type == WDS_ADD)
                        prism2_wds_add(local, entry->addr, 0);
                else if (entry->type == WDS_DEL)
                        prism2_wds_del(local, entry->addr, 0, 1);

                prev = entry;
                entry = entry->next;
                kfree(prev);
        }
}


/* Called only as a scheduled task for pending AP frames. */
static void handle_beacon(local_info_t *local, struct sk_buff *skb,
                          struct hostap_80211_rx_status *rx_stats)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
        char *body = skb->data + IEEE80211_MGMT_HDR_LEN;
        int len, left;
        u16 beacon_int, capability;
        __le16 *pos;
        char *ssid = NULL;
        unsigned char *supp_rates = NULL;
        int ssid_len = 0, supp_rates_len = 0;
        struct sta_info *sta = NULL;
        int new_sta = 0, channel = -1;

        len = skb->len - IEEE80211_MGMT_HDR_LEN;

        if (len < 8 + 2 + 2) {
                printk(KERN_DEBUG "handle_beacon - too short payload "
                       "(len=%d)\n", len);
                return;
        }

        pos = (__le16 *) body;
        left = len;

        /* Timestamp (8 octets) */
        pos += 4; left -= 8;
        /* Beacon interval (2 octets) */
        beacon_int = le16_to_cpu(*pos);
        pos++; left -= 2;
        /* Capability information (2 octets) */
        capability = le16_to_cpu(*pos);
        pos++; left -= 2;

        if (local->ap->ap_policy != AP_OTHER_AP_EVEN_IBSS &&
            capability & WLAN_CAPABILITY_IBSS)
                return;

        if (left >= 2) {
                unsigned int ileft;
                unsigned char *u = (unsigned char *) pos;

                if (*u == WLAN_EID_SSID) {
                        u++; left--;
                        ileft = *u;
                        u++; left--;

                        if (ileft > left || ileft > MAX_SSID_LEN) {
                                PDEBUG(DEBUG_AP, "SSID: overflow\n");
                                return;
                        }

                        if (local->ap->ap_policy == AP_OTHER_AP_SAME_SSID &&
                            (ileft != strlen(local->essid) ||
                             memcmp(local->essid, u, ileft) != 0)) {
                                /* not our SSID */
                                return;
                        }

                        ssid = u;
                        ssid_len = ileft;

                        u += ileft;
                        left -= ileft;
                }

                if (*u == WLAN_EID_SUPP_RATES) {
                        u++; left--;
                        ileft = *u;
                        u++; left--;

                        if (ileft > left || ileft == 0 || ileft > 8) {
                                PDEBUG(DEBUG_AP, " - SUPP_RATES len error\n");
                                return;
                        }

                        supp_rates = u;
                        supp_rates_len = ileft;

                        u += ileft;
                        left -= ileft;
                }

                if (*u == WLAN_EID_DS_PARAMS) {
                        u++; left--;
                        ileft = *u;
                        u++; left--;

                        if (ileft > left || ileft != 1) {
                                PDEBUG(DEBUG_AP, " - DS_PARAMS len error\n");
                                return;
                        }

                        channel = *u;

                        u += ileft;
                        left -= ileft;
                }
        }

        spin_lock_bh(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta != NULL)
                atomic_inc(&sta->users);
        spin_unlock_bh(&local->ap->sta_table_lock);

        if (sta == NULL) {
                /* add new AP */
                new_sta = 1;
                sta = ap_add_sta(local->ap, hdr->addr2);
                if (sta == NULL) {
                        printk(KERN_INFO "prism2: kmalloc failed for AP "
                               "data structure\n");
                        return;
                }
                hostap_event_new_sta(local->dev, sta);

                /* mark APs authentication and associated for pseudo ad-hoc
                 * style communication */
                sta->flags = WLAN_STA_AUTH | WLAN_STA_ASSOC;

                if (local->ap->autom_ap_wds) {
                        hostap_wds_link_oper(local, sta->addr, WDS_ADD);
                }
        }

        sta->ap = 1;
        if (ssid) {
                sta->u.ap.ssid_len = ssid_len;
                memcpy(sta->u.ap.ssid, ssid, ssid_len);
                sta->u.ap.ssid[ssid_len] = '\0';
        } else {
                sta->u.ap.ssid_len = 0;
                sta->u.ap.ssid[0] = '\0';
        }
        sta->u.ap.channel = channel;
        sta->rx_packets++;
        sta->rx_bytes += len;
        sta->u.ap.last_beacon = sta->last_rx = jiffies;
        sta->capability = capability;
        sta->listen_interval = beacon_int;

        atomic_dec(&sta->users);

        if (new_sta) {
                memset(sta->supported_rates, 0, sizeof(sta->supported_rates));
                memcpy(sta->supported_rates, supp_rates, supp_rates_len);
                prism2_check_tx_rates(sta);
        }
}

#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */


/* Called only as a tasklet. */
static void handle_ap_item(local_info_t *local, struct sk_buff *skb,
                           struct hostap_80211_rx_status *rx_stats)
{
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        struct net_device *dev = local->dev;
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */
        u16 fc, type, stype;
        struct ieee80211_hdr *hdr;

        /* FIX: should give skb->len to handler functions and check that the
         * buffer is long enough */
        hdr = (struct ieee80211_hdr *) skb->data;
        fc = le16_to_cpu(hdr->frame_control);
        type = fc & IEEE80211_FCTL_FTYPE;
        stype = fc & IEEE80211_FCTL_STYPE;

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        if (!local->hostapd && type == IEEE80211_FTYPE_DATA) {
                PDEBUG(DEBUG_AP, "handle_ap_item - data frame\n");

                if (!(fc & IEEE80211_FCTL_TODS) ||
                    (fc & IEEE80211_FCTL_FROMDS)) {
                        if (stype == IEEE80211_STYPE_NULLFUNC) {
                                /* no ToDS nullfunc seems to be used to check
                                 * AP association; so send reject message to
                                 * speed up re-association */
                                ap_handle_dropped_data(local, hdr);
                                goto done;
                        }
                        PDEBUG(DEBUG_AP, "   not ToDS frame (fc=0x%04x)\n",
                               fc);
                        goto done;
                }

                if (!ether_addr_equal(hdr->addr1, dev->dev_addr)) {
                        PDEBUG(DEBUG_AP, "handle_ap_item - addr1(BSSID)=%pM"
                               " not own MAC\n", hdr->addr1);
                        goto done;
                }

                if (local->ap->nullfunc_ack &&
                    stype == IEEE80211_STYPE_NULLFUNC)
                        ap_handle_data_nullfunc(local, hdr);
                else
                        ap_handle_dropped_data(local, hdr);
                goto done;
        }

        if (type == IEEE80211_FTYPE_MGMT && stype == IEEE80211_STYPE_BEACON) {
                handle_beacon(local, skb, rx_stats);
                goto done;
        }
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

        if (type == IEEE80211_FTYPE_CTL && stype == IEEE80211_STYPE_PSPOLL) {
                handle_pspoll(local, hdr, rx_stats);
                goto done;
        }

        if (local->hostapd) {
                PDEBUG(DEBUG_AP, "Unknown frame in AP queue: type=0x%02x "
                       "subtype=0x%02x\n", type, stype);
                goto done;
        }

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
        if (type != IEEE80211_FTYPE_MGMT) {
                PDEBUG(DEBUG_AP, "handle_ap_item - not a management frame?\n");
                goto done;
        }

        if (!ether_addr_equal(hdr->addr1, dev->dev_addr)) {
                PDEBUG(DEBUG_AP, "handle_ap_item - addr1(DA)=%pM"
                       " not own MAC\n", hdr->addr1);
                goto done;
        }

        if (!ether_addr_equal(hdr->addr3, dev->dev_addr)) {
                PDEBUG(DEBUG_AP, "handle_ap_item - addr3(BSSID)=%pM"
                       " not own MAC\n", hdr->addr3);
                goto done;
        }

        switch (stype) {
        case IEEE80211_STYPE_ASSOC_REQ:
                handle_assoc(local, skb, rx_stats, 0);
                break;
        case IEEE80211_STYPE_ASSOC_RESP:
                PDEBUG(DEBUG_AP, "==> ASSOC RESP (ignored)\n");
                break;
        case IEEE80211_STYPE_REASSOC_REQ:
                handle_assoc(local, skb, rx_stats, 1);
                break;
        case IEEE80211_STYPE_REASSOC_RESP:
                PDEBUG(DEBUG_AP, "==> REASSOC RESP (ignored)\n");
                break;
        case IEEE80211_STYPE_ATIM:
                PDEBUG(DEBUG_AP, "==> ATIM (ignored)\n");
                break;
        case IEEE80211_STYPE_DISASSOC:
                handle_disassoc(local, skb, rx_stats);
                break;
        case IEEE80211_STYPE_AUTH:
                handle_authen(local, skb, rx_stats);
                break;
        case IEEE80211_STYPE_DEAUTH:
                handle_deauth(local, skb, rx_stats);
                break;
        default:
                PDEBUG(DEBUG_AP, "Unknown mgmt frame subtype 0x%02x\n",
                       stype >> 4);
                break;
        }
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

 done:
        dev_kfree_skb(skb);
}


/* Called only as a tasklet (software IRQ) */
void hostap_rx(struct net_device *dev, struct sk_buff *skb,
               struct hostap_80211_rx_status *rx_stats)
{
        struct hostap_interface *iface;
        local_info_t *local;
        struct ieee80211_hdr *hdr;

        iface = netdev_priv(dev);
        local = iface->local;

        if (skb->len < 16)
                goto drop;

        dev->stats.rx_packets++;

        hdr = (struct ieee80211_hdr *) skb->data;

        if (local->ap->ap_policy == AP_OTHER_AP_SKIP_ALL &&
            ieee80211_is_beacon(hdr->frame_control))
                goto drop;

        skb->protocol = cpu_to_be16(ETH_P_HOSTAP);
        handle_ap_item(local, skb, rx_stats);
        return;

 drop:
        dev_kfree_skb(skb);
}


/* Called only as a tasklet (software IRQ) */
static void schedule_packet_send(local_info_t *local, struct sta_info *sta)
{
        struct sk_buff *skb;
        struct ieee80211_hdr *hdr;
        struct hostap_80211_rx_status rx_stats;

        if (skb_queue_empty(&sta->tx_buf))
                return;

        skb = dev_alloc_skb(16);
        if (skb == NULL) {
                printk(KERN_DEBUG "%s: schedule_packet_send: skb alloc "
                       "failed\n", local->dev->name);
                return;
        }

        hdr = skb_put(skb, 16);

        /* Generate a fake pspoll frame to start packet delivery */
        hdr->frame_control = cpu_to_le16(
                IEEE80211_FTYPE_CTL | IEEE80211_STYPE_PSPOLL);
        memcpy(hdr->addr1, local->dev->dev_addr, ETH_ALEN);
        memcpy(hdr->addr2, sta->addr, ETH_ALEN);
        hdr->duration_id = cpu_to_le16(sta->aid | BIT(15) | BIT(14));

        PDEBUG(DEBUG_PS2,
               "%s: Scheduling buffered packet delivery for STA %pM\n",
               local->dev->name, sta->addr);

        skb->dev = local->dev;

        memset(&rx_stats, 0, sizeof(rx_stats));
        hostap_rx(local->dev, skb, &rx_stats);
}


int prism2_ap_get_sta_qual(local_info_t *local, struct sockaddr addr[],
                           struct iw_quality qual[], int buf_size,
                           int aplist)
{
        struct ap_data *ap = local->ap;
        struct list_head *ptr;
        int count = 0;

        spin_lock_bh(&ap->sta_table_lock);

        for (ptr = ap->sta_list.next; ptr != NULL && ptr != &ap->sta_list;
             ptr = ptr->next) {
                struct sta_info *sta = (struct sta_info *) ptr;

                if (aplist && !sta->ap)
                        continue;
                addr[count].sa_family = ARPHRD_ETHER;
                memcpy(addr[count].sa_data, sta->addr, ETH_ALEN);
                if (sta->last_rx_silence == 0)
                        qual[count].qual = sta->last_rx_signal < 27 ?
                                0 : (sta->last_rx_signal - 27) * 92 / 127;
                else
                        qual[count].qual = sta->last_rx_signal -
                                sta->last_rx_silence - 35;
                qual[count].level = HFA384X_LEVEL_TO_dBm(sta->last_rx_signal);
                qual[count].noise = HFA384X_LEVEL_TO_dBm(sta->last_rx_silence);
                qual[count].updated = sta->last_rx_updated;

                sta->last_rx_updated = IW_QUAL_DBM;

                count++;
                if (count >= buf_size)
                        break;
        }
        spin_unlock_bh(&ap->sta_table_lock);

        return count;
}


/* Translate our list of Access Points & Stations to a card independent
 * format that the Wireless Tools will understand - Jean II */
int prism2_ap_translate_scan(struct net_device *dev,
                             struct iw_request_info *info, char *buffer)
{
        struct hostap_interface *iface;
        local_info_t *local;
        struct ap_data *ap;
        struct list_head *ptr;
        struct iw_event iwe;
        char *current_ev = buffer;
        char *end_buf = buffer + IW_SCAN_MAX_DATA;
#if !defined(PRISM2_NO_KERNEL_IEEE80211_MGMT)
        char buf[64];
#endif

        iface = netdev_priv(dev);
        local = iface->local;
        ap = local->ap;

        spin_lock_bh(&ap->sta_table_lock);

        for (ptr = ap->sta_list.next; ptr != NULL && ptr != &ap->sta_list;
             ptr = ptr->next) {
                struct sta_info *sta = (struct sta_info *) ptr;

                /* First entry *MUST* be the AP MAC address */
                memset(&iwe, 0, sizeof(iwe));
                iwe.cmd = SIOCGIWAP;
                iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
                memcpy(iwe.u.ap_addr.sa_data, sta->addr, ETH_ALEN);
                iwe.len = IW_EV_ADDR_LEN;
                current_ev = iwe_stream_add_event(info, current_ev, end_buf,
                                                  &iwe, IW_EV_ADDR_LEN);

                /* Use the mode to indicate if it's a station or
                 * an Access Point */
                memset(&iwe, 0, sizeof(iwe));
                iwe.cmd = SIOCGIWMODE;
                if (sta->ap)
                        iwe.u.mode = IW_MODE_MASTER;
                else
                        iwe.u.mode = IW_MODE_INFRA;
                iwe.len = IW_EV_UINT_LEN;
                current_ev = iwe_stream_add_event(info, current_ev, end_buf,
                                                  &iwe, IW_EV_UINT_LEN);

                /* Some quality */
                memset(&iwe, 0, sizeof(iwe));
                iwe.cmd = IWEVQUAL;
                if (sta->last_rx_silence == 0)
                        iwe.u.qual.qual = sta->last_rx_signal < 27 ?
                                0 : (sta->last_rx_signal - 27) * 92 / 127;
                else
                        iwe.u.qual.qual = sta->last_rx_signal -
                                sta->last_rx_silence - 35;
                iwe.u.qual.level = HFA384X_LEVEL_TO_dBm(sta->last_rx_signal);
                iwe.u.qual.noise = HFA384X_LEVEL_TO_dBm(sta->last_rx_silence);
                iwe.u.qual.updated = sta->last_rx_updated;
                iwe.len = IW_EV_QUAL_LEN;
                current_ev = iwe_stream_add_event(info, current_ev, end_buf,
                                                  &iwe, IW_EV_QUAL_LEN);

#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
                if (sta->ap) {
                        memset(&iwe, 0, sizeof(iwe));
                        iwe.cmd = SIOCGIWESSID;
                        iwe.u.data.length = sta->u.ap.ssid_len;
                        iwe.u.data.flags = 1;
                        current_ev = iwe_stream_add_point(info, current_ev,
                                                          end_buf, &iwe,
                                                          sta->u.ap.ssid);

                        memset(&iwe, 0, sizeof(iwe));
                        iwe.cmd = SIOCGIWENCODE;
                        if (sta->capability & WLAN_CAPABILITY_PRIVACY)
                                iwe.u.data.flags =
                                        IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
                        else
                                iwe.u.data.flags = IW_ENCODE_DISABLED;
                        current_ev = iwe_stream_add_point(info, current_ev,
                                                          end_buf, &iwe,
                                                          sta->u.ap.ssid);

                        if (sta->u.ap.channel > 0 &&
                            sta->u.ap.channel <= FREQ_COUNT) {
                                memset(&iwe, 0, sizeof(iwe));
                                iwe.cmd = SIOCGIWFREQ;
                                iwe.u.freq.m = freq_list[sta->u.ap.channel - 1]
                                        * 100000;
                                iwe.u.freq.e = 1;
                                current_ev = iwe_stream_add_event(
                                        info, current_ev, end_buf, &iwe,
                                        IW_EV_FREQ_LEN);
                        }

                        memset(&iwe, 0, sizeof(iwe));
                        iwe.cmd = IWEVCUSTOM;
                        sprintf(buf, "beacon_interval=%d",
                                sta->listen_interval);
                        iwe.u.data.length = strlen(buf);
                        current_ev = iwe_stream_add_point(info, current_ev,
                                                          end_buf, &iwe, buf);
                }
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */

                sta->last_rx_updated = IW_QUAL_DBM;

                /* To be continued, we should make good use of IWEVCUSTOM */
        }

        spin_unlock_bh(&ap->sta_table_lock);

        return current_ev - buffer;
}


static int prism2_hostapd_add_sta(struct ap_data *ap,
                                  struct prism2_hostapd_param *param)
{
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, param->sta_addr);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&ap->sta_table_lock);

        if (sta == NULL) {
                sta = ap_add_sta(ap, param->sta_addr);
                if (sta == NULL)
                        return -1;
        }

        if (!(sta->flags & WLAN_STA_ASSOC) && !sta->ap && sta->local)
                hostap_event_new_sta(sta->local->dev, sta);

        sta->flags |= WLAN_STA_AUTH | WLAN_STA_ASSOC;
        sta->last_rx = jiffies;
        sta->aid = param->u.add_sta.aid;
        sta->capability = param->u.add_sta.capability;
        sta->tx_supp_rates = param->u.add_sta.tx_supp_rates;
        if (sta->tx_supp_rates & WLAN_RATE_1M)
                sta->supported_rates[0] = 2;
        if (sta->tx_supp_rates & WLAN_RATE_2M)
                sta->supported_rates[1] = 4;
        if (sta->tx_supp_rates & WLAN_RATE_5M5)
                sta->supported_rates[2] = 11;
        if (sta->tx_supp_rates & WLAN_RATE_11M)
                sta->supported_rates[3] = 22;
        prism2_check_tx_rates(sta);
        atomic_dec(&sta->users);
        return 0;
}


static int prism2_hostapd_remove_sta(struct ap_data *ap,
                                     struct prism2_hostapd_param *param)
{
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, param->sta_addr);
        if (sta) {
                ap_sta_hash_del(ap, sta);
                list_del(&sta->list);
        }
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta)
                return -ENOENT;

        if ((sta->flags & WLAN_STA_ASSOC) && !sta->ap && sta->local)
                hostap_event_expired_sta(sta->local->dev, sta);
        ap_free_sta(ap, sta);

        return 0;
}


static int prism2_hostapd_get_info_sta(struct ap_data *ap,
                                       struct prism2_hostapd_param *param)
{
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, param->sta_addr);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta)
                return -ENOENT;

        param->u.get_info_sta.inactive_sec = (jiffies - sta->last_rx) / HZ;

        atomic_dec(&sta->users);

        return 1;
}


static int prism2_hostapd_set_flags_sta(struct ap_data *ap,
                                        struct prism2_hostapd_param *param)
{
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, param->sta_addr);
        if (sta) {
                sta->flags |= param->u.set_flags_sta.flags_or;
                sta->flags &= param->u.set_flags_sta.flags_and;
        }
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta)
                return -ENOENT;

        return 0;
}


static int prism2_hostapd_sta_clear_stats(struct ap_data *ap,
                                          struct prism2_hostapd_param *param)
{
        struct sta_info *sta;
        int rate;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, param->sta_addr);
        if (sta) {
                sta->rx_packets = sta->tx_packets = 0;
                sta->rx_bytes = sta->tx_bytes = 0;
                for (rate = 0; rate < WLAN_RATE_COUNT; rate++) {
                        sta->tx_count[rate] = 0;
                        sta->rx_count[rate] = 0;
                }
        }
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta)
                return -ENOENT;

        return 0;
}


int prism2_hostapd(struct ap_data *ap, struct prism2_hostapd_param *param)
{
        switch (param->cmd) {
        case PRISM2_HOSTAPD_FLUSH:
                ap_control_kickall(ap);
                return 0;
        case PRISM2_HOSTAPD_ADD_STA:
                return prism2_hostapd_add_sta(ap, param);
        case PRISM2_HOSTAPD_REMOVE_STA:
                return prism2_hostapd_remove_sta(ap, param);
        case PRISM2_HOSTAPD_GET_INFO_STA:
                return prism2_hostapd_get_info_sta(ap, param);
        case PRISM2_HOSTAPD_SET_FLAGS_STA:
                return prism2_hostapd_set_flags_sta(ap, param);
        case PRISM2_HOSTAPD_STA_CLEAR_STATS:
                return prism2_hostapd_sta_clear_stats(ap, param);
        default:
                printk(KERN_WARNING "prism2_hostapd: unknown cmd=%d\n",
                       param->cmd);
                return -EOPNOTSUPP;
        }
}


/* Update station info for host-based TX rate control and return current
 * TX rate */
static int ap_update_sta_tx_rate(struct sta_info *sta, struct net_device *dev)
{
        int ret = sta->tx_rate;
        struct hostap_interface *iface;
        local_info_t *local;

        iface = netdev_priv(dev);
        local = iface->local;

        sta->tx_count[sta->tx_rate_idx]++;
        sta->tx_since_last_failure++;
        sta->tx_consecutive_exc = 0;
        if (sta->tx_since_last_failure >= WLAN_RATE_UPDATE_COUNT &&
            sta->tx_rate_idx < sta->tx_max_rate) {
                /* use next higher rate */
                int old_rate, new_rate;
                old_rate = new_rate = sta->tx_rate_idx;
                while (new_rate < sta->tx_max_rate) {
                        new_rate++;
                        if (ap_tx_rate_ok(new_rate, sta, local)) {
                                sta->tx_rate_idx = new_rate;
                                break;
                        }
                }
                if (old_rate != sta->tx_rate_idx) {
                        switch (sta->tx_rate_idx) {
                        case 0: sta->tx_rate = 10; break;
                        case 1: sta->tx_rate = 20; break;
                        case 2: sta->tx_rate = 55; break;
                        case 3: sta->tx_rate = 110; break;
                        default: sta->tx_rate = 0; break;
                        }
                        PDEBUG(DEBUG_AP, "%s: STA %pM TX rate raised to %d\n",
                               dev->name, sta->addr, sta->tx_rate);
                }
                sta->tx_since_last_failure = 0;
        }

        return ret;
}


/* Called only from software IRQ. Called for each TX frame prior possible
 * encryption and transmit. */
ap_tx_ret hostap_handle_sta_tx(local_info_t *local, struct hostap_tx_data *tx)
{
        struct sta_info *sta = NULL;
        struct sk_buff *skb = tx->skb;
        int set_tim, ret;
        struct ieee80211_hdr *hdr;
        struct hostap_skb_tx_data *meta;

        meta = (struct hostap_skb_tx_data *) skb->cb;
        ret = AP_TX_CONTINUE;
        if (local->ap == NULL || skb->len < 10 ||
            meta->iface->type == HOSTAP_INTERFACE_STA)
                goto out;

        hdr = (struct ieee80211_hdr *) skb->data;

        if (hdr->addr1[0] & 0x01) {
                /* broadcast/multicast frame - no AP related processing */
                if (local->ap->num_sta <= 0)
                        ret = AP_TX_DROP;
                goto out;
        }

        /* unicast packet - check whether destination STA is associated */
        spin_lock(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr1);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&local->ap->sta_table_lock);

        if (local->iw_mode == IW_MODE_MASTER && sta == NULL &&
            !(meta->flags & HOSTAP_TX_FLAGS_WDS) &&
            meta->iface->type != HOSTAP_INTERFACE_MASTER &&
            meta->iface->type != HOSTAP_INTERFACE_AP) {
#if 0
                /* This can happen, e.g., when wlan0 is added to a bridge and
                 * bridging code does not know which port is the correct target
                 * for a unicast frame. In this case, the packet is send to all
                 * ports of the bridge. Since this is a valid scenario, do not
                 * print out any errors here. */
                if (net_ratelimit()) {
                        printk(KERN_DEBUG "AP: drop packet to non-associated "
                               "STA %pM\n", hdr->addr1);
                }
#endif
                local->ap->tx_drop_nonassoc++;
                ret = AP_TX_DROP;
                goto out;
        }

        if (sta == NULL)
                goto out;

        if (!(sta->flags & WLAN_STA_AUTHORIZED))
                ret = AP_TX_CONTINUE_NOT_AUTHORIZED;

        /* Set tx_rate if using host-based TX rate control */
        if (!local->fw_tx_rate_control)
                local->ap->last_tx_rate = meta->rate =
                        ap_update_sta_tx_rate(sta, local->dev);

        if (local->iw_mode != IW_MODE_MASTER)
                goto out;

        if (!(sta->flags & WLAN_STA_PS))
                goto out;

        if (meta->flags & HOSTAP_TX_FLAGS_ADD_MOREDATA) {
                /* indicate to STA that more frames follow */
                hdr->frame_control |=
                        cpu_to_le16(IEEE80211_FCTL_MOREDATA);
        }

        if (meta->flags & HOSTAP_TX_FLAGS_BUFFERED_FRAME) {
                /* packet was already buffered and now send due to
                 * PS poll, so do not rebuffer it */
                goto out;
        }

        if (skb_queue_len(&sta->tx_buf) >= STA_MAX_TX_BUFFER) {
                PDEBUG(DEBUG_PS, "%s: No more space in STA (%pM)'s"
                       "PS mode buffer\n",
                       local->dev->name, sta->addr);
                /* Make sure that TIM is set for the station (it might not be
                 * after AP wlan hw reset). */
                /* FIX: should fix hw reset to restore bits based on STA
                 * buffer state.. */
                hostap_set_tim(local, sta->aid, 1);
                sta->flags |= WLAN_STA_TIM;
                ret = AP_TX_DROP;
                goto out;
        }

        /* STA in PS mode, buffer frame for later delivery */
        set_tim = skb_queue_empty(&sta->tx_buf);
        skb_queue_tail(&sta->tx_buf, skb);
        /* FIX: could save RX time to skb and expire buffered frames after
         * some time if STA does not poll for them */

        if (set_tim) {
                if (sta->flags & WLAN_STA_TIM)
                        PDEBUG(DEBUG_PS2, "Re-setting TIM for aid %d\n",
                               sta->aid);
                hostap_set_tim(local, sta->aid, 1);
                sta->flags |= WLAN_STA_TIM;
        }

        ret = AP_TX_BUFFERED;

 out:
        if (sta != NULL) {
                if (ret == AP_TX_CONTINUE ||
                    ret == AP_TX_CONTINUE_NOT_AUTHORIZED) {
                        sta->tx_packets++;
                        sta->tx_bytes += skb->len;
                        sta->last_tx = jiffies;
                }

                if ((ret == AP_TX_CONTINUE ||
                     ret == AP_TX_CONTINUE_NOT_AUTHORIZED) &&
                    sta->crypt && tx->host_encrypt) {
                        tx->crypt = sta->crypt;
                        tx->sta_ptr = sta; /* hostap_handle_sta_release() will
                                            * be called to release sta info
                                            * later */
                } else
                        atomic_dec(&sta->users);
        }

        return ret;
}


void hostap_handle_sta_release(void *ptr)
{
        struct sta_info *sta = ptr;
        atomic_dec(&sta->users);
}


/* Called only as a tasklet (software IRQ) */
void hostap_handle_sta_tx_exc(local_info_t *local, struct sk_buff *skb)
{
        struct sta_info *sta;
        struct ieee80211_hdr *hdr;
        struct hostap_skb_tx_data *meta;

        hdr = (struct ieee80211_hdr *) skb->data;
        meta = (struct hostap_skb_tx_data *) skb->cb;

        spin_lock(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr1);
        if (!sta) {
                spin_unlock(&local->ap->sta_table_lock);
                PDEBUG(DEBUG_AP, "%s: Could not find STA %pM"
                       " for this TX error (@%lu)\n",
                       local->dev->name, hdr->addr1, jiffies);
                return;
        }

        sta->tx_since_last_failure = 0;
        sta->tx_consecutive_exc++;

        if (sta->tx_consecutive_exc >= WLAN_RATE_DECREASE_THRESHOLD &&
            sta->tx_rate_idx > 0 && meta->rate <= sta->tx_rate) {
                /* use next lower rate */
                int old, rate;
                old = rate = sta->tx_rate_idx;
                while (rate > 0) {
                        rate--;
                        if (ap_tx_rate_ok(rate, sta, local)) {
                                sta->tx_rate_idx = rate;
                                break;
                        }
                }
                if (old != sta->tx_rate_idx) {
                        switch (sta->tx_rate_idx) {
                        case 0: sta->tx_rate = 10; break;
                        case 1: sta->tx_rate = 20; break;
                        case 2: sta->tx_rate = 55; break;
                        case 3: sta->tx_rate = 110; break;
                        default: sta->tx_rate = 0; break;
                        }
                        PDEBUG(DEBUG_AP,
                               "%s: STA %pM TX rate lowered to %d\n",
                               local->dev->name, sta->addr, sta->tx_rate);
                }
                sta->tx_consecutive_exc = 0;
        }
        spin_unlock(&local->ap->sta_table_lock);
}


static void hostap_update_sta_ps2(local_info_t *local, struct sta_info *sta,
                                  int pwrmgt, int type, int stype)
{
        if (pwrmgt && !(sta->flags & WLAN_STA_PS)) {
                sta->flags |= WLAN_STA_PS;
                PDEBUG(DEBUG_PS2, "STA %pM changed to use PS "
                       "mode (type=0x%02X, stype=0x%02X)\n",
                       sta->addr, type >> 2, stype >> 4);
        } else if (!pwrmgt && (sta->flags & WLAN_STA_PS)) {
                sta->flags &= ~WLAN_STA_PS;
                PDEBUG(DEBUG_PS2, "STA %pM changed to not use "
                       "PS mode (type=0x%02X, stype=0x%02X)\n",
                       sta->addr, type >> 2, stype >> 4);
                if (type != IEEE80211_FTYPE_CTL ||
                    stype != IEEE80211_STYPE_PSPOLL)
                        schedule_packet_send(local, sta);
        }
}


/* Called only as a tasklet (software IRQ). Called for each RX frame to update
 * STA power saving state. pwrmgt is a flag from 802.11 frame_control field. */
int hostap_update_sta_ps(local_info_t *local, struct ieee80211_hdr *hdr)
{
        struct sta_info *sta;
        u16 fc;

        spin_lock(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&local->ap->sta_table_lock);

        if (!sta)
                return -1;

        fc = le16_to_cpu(hdr->frame_control);
        hostap_update_sta_ps2(local, sta, fc & IEEE80211_FCTL_PM,
                              fc & IEEE80211_FCTL_FTYPE,
                              fc & IEEE80211_FCTL_STYPE);

        atomic_dec(&sta->users);
        return 0;
}


/* Called only as a tasklet (software IRQ). Called for each RX frame after
 * getting RX header and payload from hardware. */
ap_rx_ret hostap_handle_sta_rx(local_info_t *local, struct net_device *dev,
                               struct sk_buff *skb,
                               struct hostap_80211_rx_status *rx_stats,
                               int wds)
{
        int ret;
        struct sta_info *sta;
        u16 fc, type, stype;
        struct ieee80211_hdr *hdr;

        if (local->ap == NULL)
                return AP_RX_CONTINUE;

        hdr = (struct ieee80211_hdr *) skb->data;

        fc = le16_to_cpu(hdr->frame_control);
        type = fc & IEEE80211_FCTL_FTYPE;
        stype = fc & IEEE80211_FCTL_STYPE;

        spin_lock(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&local->ap->sta_table_lock);

        if (sta && !(sta->flags & WLAN_STA_AUTHORIZED))
                ret = AP_RX_CONTINUE_NOT_AUTHORIZED;
        else
                ret = AP_RX_CONTINUE;


        if (fc & IEEE80211_FCTL_TODS) {
                if (!wds && (sta == NULL || !(sta->flags & WLAN_STA_ASSOC))) {
                        if (local->hostapd) {
                                prism2_rx_80211(local->apdev, skb, rx_stats,
                                                PRISM2_RX_NON_ASSOC);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
                        } else {
                                printk(KERN_DEBUG "%s: dropped received packet"
                                       " from non-associated STA %pM"
                                       " (type=0x%02x, subtype=0x%02x)\n",
                                       dev->name, hdr->addr2,
                                       type >> 2, stype >> 4);
                                hostap_rx(dev, skb, rx_stats);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */
                        }
                        ret = AP_RX_EXIT;
                        goto out;
                }
        } else if (fc & IEEE80211_FCTL_FROMDS) {
                if (!wds) {
                        /* FromDS frame - not for us; probably
                         * broadcast/multicast in another BSS - drop */
                        if (ether_addr_equal(hdr->addr1, dev->dev_addr)) {
                                printk(KERN_DEBUG "Odd.. FromDS packet "
                                       "received with own BSSID\n");
                                hostap_dump_rx_80211(dev->name, skb, rx_stats);
                        }
                        ret = AP_RX_DROP;
                        goto out;
                }
        } else if (stype == IEEE80211_STYPE_NULLFUNC && sta == NULL &&
                   ether_addr_equal(hdr->addr1, dev->dev_addr)) {

                if (local->hostapd) {
                        prism2_rx_80211(local->apdev, skb, rx_stats,
                                        PRISM2_RX_NON_ASSOC);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
                } else {
                        /* At least Lucent f/w seems to send data::nullfunc
                         * frames with no ToDS flag when the current AP returns
                         * after being unavailable for some time. Speed up
                         * re-association by informing the station about it not
                         * being associated. */
                        printk(KERN_DEBUG "%s: rejected received nullfunc frame"
                               " without ToDS from not associated STA %pM\n",
                               dev->name, hdr->addr2);
                        hostap_rx(dev, skb, rx_stats);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */
                }
                ret = AP_RX_EXIT;
                goto out;
        } else if (stype == IEEE80211_STYPE_NULLFUNC) {
                /* At least Lucent cards seem to send periodic nullfunc
                 * frames with ToDS. Let these through to update SQ
                 * stats and PS state. Nullfunc frames do not contain
                 * any data and they will be dropped below. */
        } else {
                /* If BSSID (Addr3) is foreign, this frame is a normal
                 * broadcast frame from an IBSS network. Drop it silently.
                 * If BSSID is own, report the dropping of this frame. */
                if (ether_addr_equal(hdr->addr3, dev->dev_addr)) {
                        printk(KERN_DEBUG "%s: dropped received packet from %pM"
                               " with no ToDS flag "
                               "(type=0x%02x, subtype=0x%02x)\n", dev->name,
                               hdr->addr2, type >> 2, stype >> 4);
                        hostap_dump_rx_80211(dev->name, skb, rx_stats);
                }
                ret = AP_RX_DROP;
                goto out;
        }

        if (sta) {
                hostap_update_sta_ps2(local, sta, fc & IEEE80211_FCTL_PM,
                                      type, stype);

                sta->rx_packets++;
                sta->rx_bytes += skb->len;
                sta->last_rx = jiffies;
        }

        if (local->ap->nullfunc_ack && stype == IEEE80211_STYPE_NULLFUNC &&
            fc & IEEE80211_FCTL_TODS) {
                if (local->hostapd) {
                        prism2_rx_80211(local->apdev, skb, rx_stats,
                                        PRISM2_RX_NULLFUNC_ACK);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
                } else {
                        /* some STA f/w's seem to require control::ACK frame
                         * for data::nullfunc, but Prism2 f/w 0.8.0 (at least
                         * from Compaq) does not send this.. Try to generate
                         * ACK for these frames from the host driver to make
                         * power saving work with, e.g., Lucent WaveLAN f/w */
                        hostap_rx(dev, skb, rx_stats);
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */
                }
                ret = AP_RX_EXIT;
                goto out;
        }

 out:
        if (sta)
                atomic_dec(&sta->users);

        return ret;
}


/* Called only as a tasklet (software IRQ) */
int hostap_handle_sta_crypto(local_info_t *local,
                             struct ieee80211_hdr *hdr,
                             struct lib80211_crypt_data **crypt,
                             void **sta_ptr)
{
        struct sta_info *sta;

        spin_lock(&local->ap->sta_table_lock);
        sta = ap_get_sta(local->ap, hdr->addr2);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock(&local->ap->sta_table_lock);

        if (!sta)
                return -1;

        if (sta->crypt) {
                *crypt = sta->crypt;
                *sta_ptr = sta;
                /* hostap_handle_sta_release() will be called to release STA
                 * info */
        } else
                atomic_dec(&sta->users);

        return 0;
}


/* Called only as a tasklet (software IRQ) */
int hostap_is_sta_assoc(struct ap_data *ap, u8 *sta_addr)
{
        struct sta_info *sta;
        int ret = 0;

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, sta_addr);
        if (sta != NULL && (sta->flags & WLAN_STA_ASSOC) && !sta->ap)
                ret = 1;
        spin_unlock(&ap->sta_table_lock);

        return ret;
}


/* Called only as a tasklet (software IRQ) */
int hostap_is_sta_authorized(struct ap_data *ap, u8 *sta_addr)
{
        struct sta_info *sta;
        int ret = 0;

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, sta_addr);
        if (sta != NULL && (sta->flags & WLAN_STA_ASSOC) && !sta->ap &&
            ((sta->flags & WLAN_STA_AUTHORIZED) ||
             ap->local->ieee_802_1x == 0))
                ret = 1;
        spin_unlock(&ap->sta_table_lock);

        return ret;
}


/* Called only as a tasklet (software IRQ) */
int hostap_add_sta(struct ap_data *ap, u8 *sta_addr)
{
        struct sta_info *sta;
        int ret = 1;

        if (!ap)
                return -1;

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, sta_addr);
        if (sta)
                ret = 0;
        spin_unlock(&ap->sta_table_lock);

        if (ret == 1) {
                sta = ap_add_sta(ap, sta_addr);
                if (!sta)
                        return -1;
                sta->flags = WLAN_STA_AUTH | WLAN_STA_ASSOC;
                sta->ap = 1;
                memset(sta->supported_rates, 0, sizeof(sta->supported_rates));
                /* No way of knowing which rates are supported since we did not
                 * get supported rates element from beacon/assoc req. Assume
                 * that remote end supports all 802.11b rates. */
                sta->supported_rates[0] = 0x82;
                sta->supported_rates[1] = 0x84;
                sta->supported_rates[2] = 0x0b;
                sta->supported_rates[3] = 0x16;
                sta->tx_supp_rates = WLAN_RATE_1M | WLAN_RATE_2M |
                        WLAN_RATE_5M5 | WLAN_RATE_11M;
                sta->tx_rate = 110;
                sta->tx_max_rate = sta->tx_rate_idx = 3;
        }

        return ret;
}


/* Called only as a tasklet (software IRQ) */
int hostap_update_rx_stats(struct ap_data *ap,
                           struct ieee80211_hdr *hdr,
                           struct hostap_80211_rx_status *rx_stats)
{
        struct sta_info *sta;

        if (!ap)
                return -1;

        spin_lock(&ap->sta_table_lock);
        sta = ap_get_sta(ap, hdr->addr2);
        if (sta) {
                sta->last_rx_silence = rx_stats->noise;
                sta->last_rx_signal = rx_stats->signal;
                sta->last_rx_rate = rx_stats->rate;
                sta->last_rx_updated = IW_QUAL_ALL_UPDATED | IW_QUAL_DBM;
                if (rx_stats->rate == 10)
                        sta->rx_count[0]++;
                else if (rx_stats->rate == 20)
                        sta->rx_count[1]++;
                else if (rx_stats->rate == 55)
                        sta->rx_count[2]++;
                else if (rx_stats->rate == 110)
                        sta->rx_count[3]++;
        }
        spin_unlock(&ap->sta_table_lock);

        return sta ? 0 : -1;
}


void hostap_update_rates(local_info_t *local)
{
        struct sta_info *sta;
        struct ap_data *ap = local->ap;

        if (!ap)
                return;

        spin_lock_bh(&ap->sta_table_lock);
        list_for_each_entry(sta, &ap->sta_list, list) {
                prism2_check_tx_rates(sta);
        }
        spin_unlock_bh(&ap->sta_table_lock);
}


void * ap_crypt_get_ptrs(struct ap_data *ap, u8 *addr, int permanent,
                         struct lib80211_crypt_data ***crypt)
{
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        sta = ap_get_sta(ap, addr);
        if (sta)
                atomic_inc(&sta->users);
        spin_unlock_bh(&ap->sta_table_lock);

        if (!sta && permanent)
                sta = ap_add_sta(ap, addr);

        if (!sta)
                return NULL;

        if (permanent)
                sta->flags |= WLAN_STA_PERM;

        *crypt = &sta->crypt;

        return sta;
}


void hostap_add_wds_links(local_info_t *local)
{
        struct ap_data *ap = local->ap;
        struct sta_info *sta;

        spin_lock_bh(&ap->sta_table_lock);
        list_for_each_entry(sta, &ap->sta_list, list) {
                if (sta->ap)
                        hostap_wds_link_oper(local, sta->addr, WDS_ADD);
        }
        spin_unlock_bh(&ap->sta_table_lock);

        schedule_work(&local->ap->wds_oper_queue);
}


void hostap_wds_link_oper(local_info_t *local, u8 *addr, wds_oper_type type)
{
        struct wds_oper_data *entry;

        entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
        if (!entry)
                return;
        memcpy(entry->addr, addr, ETH_ALEN);
        entry->type = type;
        spin_lock_bh(&local->lock);
        entry->next = local->ap->wds_oper_entries;
        local->ap->wds_oper_entries = entry;
        spin_unlock_bh(&local->lock);

        schedule_work(&local->ap->wds_oper_queue);
}


EXPORT_SYMBOL(hostap_init_data);
EXPORT_SYMBOL(hostap_init_ap_proc);
EXPORT_SYMBOL(hostap_free_data);
EXPORT_SYMBOL(hostap_check_sta_fw_version);
EXPORT_SYMBOL(hostap_handle_sta_tx_exc);
#ifndef PRISM2_NO_KERNEL_IEEE80211_MGMT
#endif /* PRISM2_NO_KERNEL_IEEE80211_MGMT */