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root/net/ieee80211/ieee80211_rx.c

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DEFINITIONS

This source file includes following definitions.
  1. ieee80211_monitor_rx
  2. ieee80211_frag_cache_find
  3. ieee80211_frag_cache_get
  4. ieee80211_frag_cache_invalidate
  5. ieee80211_rx_frame_mgmt
  6. ieee80211_is_eapol_frame
  7. ieee80211_rx_frame_decrypt
  8. ieee80211_rx_frame_decrypt_msdu
  9. ieee80211_rx
  10. ieee80211_rx_any
  11. ieee80211_verify_qos_info
  12. ieee80211_read_qos_param_element
  13. ieee80211_read_qos_info_element
  14. ieee80211_qos_convert_ac_to_parameters
  15. ieee80211_parse_qos_info_param_IE
  16. get_info_element_string
  17. ieee80211_parse_info_param
  18. ieee80211_handle_assoc_resp
  19. ieee80211_network_init
  20. is_same_network
  21. update_network
  22. is_beacon
  23. ieee80211_process_probe_response
  24. ieee80211_rx_mgt

/*
 * Original code based Host AP (software wireless LAN access point) driver
 * for Intersil Prism2/2.5/3 - hostap.o module, common routines
 *
 * Copyright (c) 2001-2002, SSH Communications Security Corp and Jouni Malinen
 * <j@w1.fi>
 * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
 * Copyright (c) 2004-2005, Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation. See README and COPYING for
 * more details.
 */

#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/in6.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/tcp.h>
#include <linux/types.h>
#include <linux/wireless.h>
#include <linux/etherdevice.h>
#include <asm/uaccess.h>
#include <linux/ctype.h>

#include <net/ieee80211.h>

static void ieee80211_monitor_rx(struct ieee80211_device *ieee,
                                        struct sk_buff *skb,
                                        struct ieee80211_rx_stats *rx_stats)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        u16 fc = le16_to_cpu(hdr->frame_ctl);

        skb->dev = ieee->dev;
        skb_reset_mac_header(skb);
        skb_pull(skb, ieee80211_get_hdrlen(fc));
        skb->pkt_type = PACKET_OTHERHOST;
        skb->protocol = htons(ETH_P_80211_RAW);
        memset(skb->cb, 0, sizeof(skb->cb));
        netif_rx(skb);
}

/* Called only as a tasklet (software IRQ) */
static struct ieee80211_frag_entry *ieee80211_frag_cache_find(struct
                                                              ieee80211_device
                                                              *ieee,
                                                              unsigned int seq,
                                                              unsigned int frag,
                                                              u8 * src,
                                                              u8 * dst)
{
        struct ieee80211_frag_entry *entry;
        int i;

        for (i = 0; i < IEEE80211_FRAG_CACHE_LEN; i++) {
                entry = &ieee->frag_cache[i];
                if (entry->skb != NULL &&
                    time_after(jiffies, entry->first_frag_time + 2 * HZ)) {
                        IEEE80211_DEBUG_FRAG("expiring fragment cache entry "
                                             "seq=%u last_frag=%u\n",
                                             entry->seq, entry->last_frag);
                        dev_kfree_skb_any(entry->skb);
                        entry->skb = NULL;
                }

                if (entry->skb != NULL && entry->seq == seq &&
                    (entry->last_frag + 1 == frag || frag == -1) &&
                    !compare_ether_addr(entry->src_addr, src) &&
                    !compare_ether_addr(entry->dst_addr, dst))
                        return entry;
        }

        return NULL;
}

/* Called only as a tasklet (software IRQ) */
static struct sk_buff *ieee80211_frag_cache_get(struct ieee80211_device *ieee,
                                                struct ieee80211_hdr_4addr *hdr)
{
        struct sk_buff *skb = NULL;
        u16 sc;
        unsigned int frag, seq;
        struct ieee80211_frag_entry *entry;

        sc = le16_to_cpu(hdr->seq_ctl);
        frag = WLAN_GET_SEQ_FRAG(sc);
        seq = WLAN_GET_SEQ_SEQ(sc);

        if (frag == 0) {
                /* Reserve enough space to fit maximum frame length */
                skb = dev_alloc_skb(ieee->dev->mtu +
                                    sizeof(struct ieee80211_hdr_4addr) +
                                    8 /* LLC */  +
                                    2 /* alignment */  +
                                    8 /* WEP */  + ETH_ALEN /* WDS */ );
                if (skb == NULL)
                        return NULL;

                entry = &ieee->frag_cache[ieee->frag_next_idx];
                ieee->frag_next_idx++;
                if (ieee->frag_next_idx >= IEEE80211_FRAG_CACHE_LEN)
                        ieee->frag_next_idx = 0;

                if (entry->skb != NULL)
                        dev_kfree_skb_any(entry->skb);

                entry->first_frag_time = jiffies;
                entry->seq = seq;
                entry->last_frag = frag;
                entry->skb = skb;
                memcpy(entry->src_addr, hdr->addr2, ETH_ALEN);
                memcpy(entry->dst_addr, hdr->addr1, ETH_ALEN);
        } else {
                /* received a fragment of a frame for which the head fragment
                 * should have already been received */
                entry = ieee80211_frag_cache_find(ieee, seq, frag, hdr->addr2,
                                                  hdr->addr1);
                if (entry != NULL) {
                        entry->last_frag = frag;
                        skb = entry->skb;
                }
        }

        return skb;
}

/* Called only as a tasklet (software IRQ) */
static int ieee80211_frag_cache_invalidate(struct ieee80211_device *ieee,
                                           struct ieee80211_hdr_4addr *hdr)
{
        u16 sc;
        unsigned int seq;
        struct ieee80211_frag_entry *entry;

        sc = le16_to_cpu(hdr->seq_ctl);
        seq = WLAN_GET_SEQ_SEQ(sc);

        entry = ieee80211_frag_cache_find(ieee, seq, -1, hdr->addr2,
                                          hdr->addr1);

        if (entry == NULL) {
                IEEE80211_DEBUG_FRAG("could not invalidate fragment cache "
                                     "entry (seq=%u)\n", seq);
                return -1;
        }

        entry->skb = NULL;
        return 0;
}

#ifdef NOT_YET
/* ieee80211_rx_frame_mgtmt
 *
 * Responsible for handling management control frames
 *
 * Called by ieee80211_rx */
static int
ieee80211_rx_frame_mgmt(struct ieee80211_device *ieee, struct sk_buff *skb,
                        struct ieee80211_rx_stats *rx_stats, u16 type,
                        u16 stype)
{
        if (ieee->iw_mode == IW_MODE_MASTER) {
                printk(KERN_DEBUG "%s: Master mode not yet suppported.\n",
                       ieee->dev->name);
                return 0;
/*
  hostap_update_sta_ps(ieee, (struct hostap_ieee80211_hdr_4addr *)
  skb->data);*/
        }

        if (ieee->hostapd && type == WLAN_FC_TYPE_MGMT) {
                if (stype == WLAN_FC_STYPE_BEACON &&
                    ieee->iw_mode == IW_MODE_MASTER) {
                        struct sk_buff *skb2;
                        /* Process beacon frames also in kernel driver to
                         * update STA(AP) table statistics */
                        skb2 = skb_clone(skb, GFP_ATOMIC);
                        if (skb2)
                                hostap_rx(skb2->dev, skb2, rx_stats);
                }

                /* send management frames to the user space daemon for
                 * processing */
                ieee->apdevstats.rx_packets++;
                ieee->apdevstats.rx_bytes += skb->len;
                prism2_rx_80211(ieee->apdev, skb, rx_stats, PRISM2_RX_MGMT);
                return 0;
        }

        if (ieee->iw_mode == IW_MODE_MASTER) {
                if (type != WLAN_FC_TYPE_MGMT && type != WLAN_FC_TYPE_CTRL) {
                        printk(KERN_DEBUG "%s: unknown management frame "
                               "(type=0x%02x, stype=0x%02x) dropped\n",
                               skb->dev->name, type, stype);
                        return -1;
                }

                hostap_rx(skb->dev, skb, rx_stats);
                return 0;
        }

        printk(KERN_DEBUG "%s: hostap_rx_frame_mgmt: management frame "
               "received in non-Host AP mode\n", skb->dev->name);
        return -1;
}
#endif

/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
static unsigned char rfc1042_header[] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };

/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
static unsigned char bridge_tunnel_header[] =
    { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
/* No encapsulation header if EtherType < 0x600 (=length) */

/* Called by ieee80211_rx_frame_decrypt */
static int ieee80211_is_eapol_frame(struct ieee80211_device *ieee,
                                    struct sk_buff *skb)
{
        struct net_device *dev = ieee->dev;
        u16 fc, ethertype;
        struct ieee80211_hdr_3addr *hdr;
        u8 *pos;

        if (skb->len < 24)
                return 0;

        hdr = (struct ieee80211_hdr_3addr *)skb->data;
        fc = le16_to_cpu(hdr->frame_ctl);

        /* check that the frame is unicast frame to us */
        if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
            IEEE80211_FCTL_TODS &&
            !compare_ether_addr(hdr->addr1, dev->dev_addr) &&
            !compare_ether_addr(hdr->addr3, dev->dev_addr)) {
                /* ToDS frame with own addr BSSID and DA */
        } else if ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
                   IEEE80211_FCTL_FROMDS &&
                   !compare_ether_addr(hdr->addr1, dev->dev_addr)) {
                /* FromDS frame with own addr as DA */
        } else
                return 0;

        if (skb->len < 24 + 8)
                return 0;

        /* check for port access entity Ethernet type */
        pos = skb->data + 24;
        ethertype = (pos[6] << 8) | pos[7];
        if (ethertype == ETH_P_PAE)
                return 1;

        return 0;
}

/* Called only as a tasklet (software IRQ), by ieee80211_rx */
static int
ieee80211_rx_frame_decrypt(struct ieee80211_device *ieee, struct sk_buff *skb,
                           struct ieee80211_crypt_data *crypt)
{
        struct ieee80211_hdr_3addr *hdr;
        int res, hdrlen;

        if (crypt == NULL || crypt->ops->decrypt_mpdu == NULL)
                return 0;

        hdr = (struct ieee80211_hdr_3addr *)skb->data;
        hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));

        atomic_inc(&crypt->refcnt);
        res = crypt->ops->decrypt_mpdu(skb, hdrlen, crypt->priv);
        atomic_dec(&crypt->refcnt);
        if (res < 0) {
                IEEE80211_DEBUG_DROP("decryption failed (SA=" MAC_FMT
                                     ") res=%d\n",
                                     hdr->addr2[0], hdr->addr2[1],
                                     hdr->addr2[2], hdr->addr2[3],
                                     hdr->addr2[4], hdr->addr2[5],
                                     res);
                if (res == -2)
                        IEEE80211_DEBUG_DROP("Decryption failed ICV "
                                             "mismatch (key %d)\n",
                                             skb->data[hdrlen + 3] >> 6);
                ieee->ieee_stats.rx_discards_undecryptable++;
                return -1;
        }

        return res;
}

/* Called only as a tasklet (software IRQ), by ieee80211_rx */
static int
ieee80211_rx_frame_decrypt_msdu(struct ieee80211_device *ieee,
                                struct sk_buff *skb, int keyidx,
                                struct ieee80211_crypt_data *crypt)
{
        struct ieee80211_hdr_3addr *hdr;
        int res, hdrlen;

        if (crypt == NULL || crypt->ops->decrypt_msdu == NULL)
                return 0;

        hdr = (struct ieee80211_hdr_3addr *)skb->data;
        hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_ctl));

        atomic_inc(&crypt->refcnt);
        res = crypt->ops->decrypt_msdu(skb, keyidx, hdrlen, crypt->priv);
        atomic_dec(&crypt->refcnt);
        if (res < 0) {
                printk(KERN_DEBUG "%s: MSDU decryption/MIC verification failed"
                       " (SA=" MAC_FMT " keyidx=%d)\n",
                       ieee->dev->name,
                       hdr->addr2[0], hdr->addr2[1],
                       hdr->addr2[2], hdr->addr2[3],
                       hdr->addr2[4], hdr->addr2[5],
                       keyidx);
                return -1;
        }

        return 0;
}

/* All received frames are sent to this function. @skb contains the frame in
 * IEEE 802.11 format, i.e., in the format it was sent over air.
 * This function is called only as a tasklet (software IRQ). */
int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb,
                 struct ieee80211_rx_stats *rx_stats)
{
        struct net_device *dev = ieee->dev;
        struct ieee80211_hdr_4addr *hdr;
        size_t hdrlen;
        u16 fc, type, stype, sc;
        struct net_device_stats *stats;
        unsigned int frag;
        u8 *payload;
        u16 ethertype;
#ifdef NOT_YET
        struct net_device *wds = NULL;
        struct sk_buff *skb2 = NULL;
        struct net_device *wds = NULL;
        int frame_authorized = 0;
        int from_assoc_ap = 0;
        void *sta = NULL;
#endif
        u8 dst[ETH_ALEN];
        u8 src[ETH_ALEN];
        struct ieee80211_crypt_data *crypt = NULL;
        int keyidx = 0;
        int can_be_decrypted = 0;
        DECLARE_MAC_BUF(mac);

        hdr = (struct ieee80211_hdr_4addr *)skb->data;
        stats = &ieee->stats;

        if (skb->len < 10) {
                printk(KERN_INFO "%s: SKB length < 10\n", dev->name);
                goto rx_dropped;
        }

        fc = le16_to_cpu(hdr->frame_ctl);
        type = WLAN_FC_GET_TYPE(fc);
        stype = WLAN_FC_GET_STYPE(fc);
        sc = le16_to_cpu(hdr->seq_ctl);
        frag = WLAN_GET_SEQ_FRAG(sc);
        hdrlen = ieee80211_get_hdrlen(fc);

        if (skb->len < hdrlen) {
                printk(KERN_INFO "%s: invalid SKB length %d\n",
                        dev->name, skb->len);
                goto rx_dropped;
        }

        /* Put this code here so that we avoid duplicating it in all
         * Rx paths. - Jean II */
#ifdef CONFIG_WIRELESS_EXT
#ifdef IW_WIRELESS_SPY          /* defined in iw_handler.h */
        /* If spy monitoring on */
        if (ieee->spy_data.spy_number > 0) {
                struct iw_quality wstats;

                wstats.updated = 0;
                if (rx_stats->mask & IEEE80211_STATMASK_RSSI) {
                        wstats.level = rx_stats->signal;
                        wstats.updated |= IW_QUAL_LEVEL_UPDATED;
                } else
                        wstats.updated |= IW_QUAL_LEVEL_INVALID;

                if (rx_stats->mask & IEEE80211_STATMASK_NOISE) {
                        wstats.noise = rx_stats->noise;
                        wstats.updated |= IW_QUAL_NOISE_UPDATED;
                } else
                        wstats.updated |= IW_QUAL_NOISE_INVALID;

                if (rx_stats->mask & IEEE80211_STATMASK_SIGNAL) {
                        wstats.qual = rx_stats->signal;
                        wstats.updated |= IW_QUAL_QUAL_UPDATED;
                } else
                        wstats.updated |= IW_QUAL_QUAL_INVALID;

                /* Update spy records */
                wireless_spy_update(ieee->dev, hdr->addr2, &wstats);
        }
#endif                          /* IW_WIRELESS_SPY */
#endif                          /* CONFIG_WIRELESS_EXT */

#ifdef NOT_YET
        hostap_update_rx_stats(local->ap, hdr, rx_stats);
#endif

        if (ieee->iw_mode == IW_MODE_MONITOR) {
                stats->rx_packets++;
                stats->rx_bytes += skb->len;
                ieee80211_monitor_rx(ieee, skb, rx_stats);
                return 1;
        }

        can_be_decrypted = (is_multicast_ether_addr(hdr->addr1) ||
                            is_broadcast_ether_addr(hdr->addr2)) ?
            ieee->host_mc_decrypt : ieee->host_decrypt;

        if (can_be_decrypted) {
                if (skb->len >= hdrlen + 3) {
                        /* Top two-bits of byte 3 are the key index */
                        keyidx = skb->data[hdrlen + 3] >> 6;
                }

                /* ieee->crypt[] is WEP_KEY (4) in length.  Given that keyidx
                 * is only allowed 2-bits of storage, no value of keyidx can
                 * be provided via above code that would result in keyidx
                 * being out of range */
                crypt = ieee->crypt[keyidx];

#ifdef NOT_YET
                sta = NULL;

                /* Use station specific key to override default keys if the
                 * receiver address is a unicast address ("individual RA"). If
                 * bcrx_sta_key parameter is set, station specific key is used
                 * even with broad/multicast targets (this is against IEEE
                 * 802.11, but makes it easier to use different keys with
                 * stations that do not support WEP key mapping). */

                if (!(hdr->addr1[0] & 0x01) || local->bcrx_sta_key)
                        (void)hostap_handle_sta_crypto(local, hdr, &crypt,
                                                       &sta);
#endif

                /* allow NULL decrypt to indicate an station specific override
                 * for default encryption */
                if (crypt && (crypt->ops == NULL ||
                              crypt->ops->decrypt_mpdu == NULL))
                        crypt = NULL;

                if (!crypt && (fc & IEEE80211_FCTL_PROTECTED)) {
                        /* This seems to be triggered by some (multicast?)
                         * frames from other than current BSS, so just drop the
                         * frames silently instead of filling system log with
                         * these reports. */
                        IEEE80211_DEBUG_DROP("Decryption failed (not set)"
                                             " (SA=" MAC_FMT ")\n",
                                             hdr->addr2[0], hdr->addr2[1],
                                             hdr->addr2[2], hdr->addr2[3],
                                             hdr->addr2[4], hdr->addr2[5]);
                        ieee->ieee_stats.rx_discards_undecryptable++;
                        goto rx_dropped;
                }
        }
#ifdef NOT_YET
        if (type != WLAN_FC_TYPE_DATA) {
                if (type == WLAN_FC_TYPE_MGMT && stype == WLAN_FC_STYPE_AUTH &&
                    fc & IEEE80211_FCTL_PROTECTED && ieee->host_decrypt &&
                    (keyidx = hostap_rx_frame_decrypt(ieee, skb, crypt)) < 0) {
                        printk(KERN_DEBUG "%s: failed to decrypt mgmt::auth "
                               "from " MAC_FMT "\n", dev->name,
                               hdr->addr2[0], hdr->addr2[1],
                               hdr->addr2[2], hdr->addr2[3],
                               hdr->addr2[4], hdr->addr2[5]);
                        /* TODO: could inform hostapd about this so that it
                         * could send auth failure report */
                        goto rx_dropped;
                }

                if (ieee80211_rx_frame_mgmt(ieee, skb, rx_stats, type, stype))
                        goto rx_dropped;
                else
                        goto rx_exit;
        }
#endif
        /* drop duplicate 802.11 retransmissions (IEEE 802.11 Chap. 9.29) */
        if (sc == ieee->prev_seq_ctl)
                goto rx_dropped;
        else
                ieee->prev_seq_ctl = sc;

        /* Data frame - extract src/dst addresses */
        if (skb->len < IEEE80211_3ADDR_LEN)
                goto rx_dropped;

        switch (fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {
        case IEEE80211_FCTL_FROMDS:
                memcpy(dst, hdr->addr1, ETH_ALEN);
                memcpy(src, hdr->addr3, ETH_ALEN);
                break;
        case IEEE80211_FCTL_TODS:
                memcpy(dst, hdr->addr3, ETH_ALEN);
                memcpy(src, hdr->addr2, ETH_ALEN);
                break;
        case IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS:
                if (skb->len < IEEE80211_4ADDR_LEN)
                        goto rx_dropped;
                memcpy(dst, hdr->addr3, ETH_ALEN);
                memcpy(src, hdr->addr4, ETH_ALEN);
                break;
        case 0:
                memcpy(dst, hdr->addr1, ETH_ALEN);
                memcpy(src, hdr->addr2, ETH_ALEN);
                break;
        }

#ifdef NOT_YET
        if (hostap_rx_frame_wds(ieee, hdr, fc, &wds))
                goto rx_dropped;
        if (wds) {
                skb->dev = dev = wds;
                stats = hostap_get_stats(dev);
        }

        if (ieee->iw_mode == IW_MODE_MASTER && !wds &&
            (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
            IEEE80211_FCTL_FROMDS && ieee->stadev
            && !compare_ether_addr(hdr->addr2, ieee->assoc_ap_addr)) {
                /* Frame from BSSID of the AP for which we are a client */
                skb->dev = dev = ieee->stadev;
                stats = hostap_get_stats(dev);
                from_assoc_ap = 1;
        }
#endif

        dev->last_rx = jiffies;

#ifdef NOT_YET
        if ((ieee->iw_mode == IW_MODE_MASTER ||
             ieee->iw_mode == IW_MODE_REPEAT) && !from_assoc_ap) {
                switch (hostap_handle_sta_rx(ieee, dev, skb, rx_stats,
                                             wds != NULL)) {
                case AP_RX_CONTINUE_NOT_AUTHORIZED:
                        frame_authorized = 0;
                        break;
                case AP_RX_CONTINUE:
                        frame_authorized = 1;
                        break;
                case AP_RX_DROP:
                        goto rx_dropped;
                case AP_RX_EXIT:
                        goto rx_exit;
                }
        }
#endif

        /* Nullfunc frames may have PS-bit set, so they must be passed to
         * hostap_handle_sta_rx() before being dropped here. */

        stype &= ~IEEE80211_STYPE_QOS_DATA;

        if (stype != IEEE80211_STYPE_DATA &&
            stype != IEEE80211_STYPE_DATA_CFACK &&
            stype != IEEE80211_STYPE_DATA_CFPOLL &&
            stype != IEEE80211_STYPE_DATA_CFACKPOLL) {
                if (stype != IEEE80211_STYPE_NULLFUNC)
                        IEEE80211_DEBUG_DROP("RX: dropped data frame "
                                             "with no data (type=0x%02x, "
                                             "subtype=0x%02x, len=%d)\n",
                                             type, stype, skb->len);
                goto rx_dropped;
        }

        /* skb: hdr + (possibly fragmented, possibly encrypted) payload */

        if ((fc & IEEE80211_FCTL_PROTECTED) && can_be_decrypted &&
            (keyidx = ieee80211_rx_frame_decrypt(ieee, skb, crypt)) < 0)
                goto rx_dropped;

        hdr = (struct ieee80211_hdr_4addr *)skb->data;

        /* skb: hdr + (possibly fragmented) plaintext payload */
        // PR: FIXME: hostap has additional conditions in the "if" below:
        // ieee->host_decrypt && (fc & IEEE80211_FCTL_PROTECTED) &&
        if ((frag != 0) || (fc & IEEE80211_FCTL_MOREFRAGS)) {
                int flen;
                struct sk_buff *frag_skb = ieee80211_frag_cache_get(ieee, hdr);
                IEEE80211_DEBUG_FRAG("Rx Fragment received (%u)\n", frag);

                if (!frag_skb) {
                        IEEE80211_DEBUG(IEEE80211_DL_RX | IEEE80211_DL_FRAG,
                                        "Rx cannot get skb from fragment "
                                        "cache (morefrag=%d seq=%u frag=%u)\n",
                                        (fc & IEEE80211_FCTL_MOREFRAGS) != 0,
                                        WLAN_GET_SEQ_SEQ(sc), frag);
                        goto rx_dropped;
                }

                flen = skb->len;
                if (frag != 0)
                        flen -= hdrlen;

                if (frag_skb->tail + flen > frag_skb->end) {
                        printk(KERN_WARNING "%s: host decrypted and "
                               "reassembled frame did not fit skb\n",
                               dev->name);
                        ieee80211_frag_cache_invalidate(ieee, hdr);
                        goto rx_dropped;
                }

                if (frag == 0) {
                        /* copy first fragment (including full headers) into
                         * beginning of the fragment cache skb */
                        skb_copy_from_linear_data(skb, skb_put(frag_skb, flen), flen);
                } else {
                        /* append frame payload to the end of the fragment
                         * cache skb */
                        skb_copy_from_linear_data_offset(skb, hdrlen,
                                      skb_put(frag_skb, flen), flen);
                }
                dev_kfree_skb_any(skb);
                skb = NULL;

                if (fc & IEEE80211_FCTL_MOREFRAGS) {
                        /* more fragments expected - leave the skb in fragment
                         * cache for now; it will be delivered to upper layers
                         * after all fragments have been received */
                        goto rx_exit;
                }

                /* this was the last fragment and the frame will be
                 * delivered, so remove skb from fragment cache */
                skb = frag_skb;
                hdr = (struct ieee80211_hdr_4addr *)skb->data;
                ieee80211_frag_cache_invalidate(ieee, hdr);
        }

        /* skb: hdr + (possible reassembled) full MSDU payload; possibly still
         * encrypted/authenticated */
        if ((fc & IEEE80211_FCTL_PROTECTED) && can_be_decrypted &&
            ieee80211_rx_frame_decrypt_msdu(ieee, skb, keyidx, crypt))
                goto rx_dropped;

        hdr = (struct ieee80211_hdr_4addr *)skb->data;
        if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !ieee->open_wep) {
                if (            /*ieee->ieee802_1x && */
                           ieee80211_is_eapol_frame(ieee, skb)) {
                        /* pass unencrypted EAPOL frames even if encryption is
                         * configured */
                } else {
                        IEEE80211_DEBUG_DROP("encryption configured, but RX "
                                             "frame not encrypted (SA="
                                             MAC_FMT ")\n",
                                             hdr->addr2[0], hdr->addr2[1],
                                             hdr->addr2[2], hdr->addr2[3],
                                             hdr->addr2[4], hdr->addr2[5]);
                        goto rx_dropped;
                }
        }

        if (crypt && !(fc & IEEE80211_FCTL_PROTECTED) && !ieee->open_wep &&
            !ieee80211_is_eapol_frame(ieee, skb)) {
                IEEE80211_DEBUG_DROP("dropped unencrypted RX data "
                                     "frame from " MAC_FMT
                                     " (drop_unencrypted=1)\n",
                                     hdr->addr2[0], hdr->addr2[1],
                                     hdr->addr2[2], hdr->addr2[3],
                                     hdr->addr2[4], hdr->addr2[5]);
                goto rx_dropped;
        }

        /* If the frame was decrypted in hardware, we may need to strip off
         * any security data (IV, ICV, etc) that was left behind */
        if (!can_be_decrypted && (fc & IEEE80211_FCTL_PROTECTED) &&
            ieee->host_strip_iv_icv) {
                int trimlen = 0;

                /* Top two-bits of byte 3 are the key index */
                if (skb->len >= hdrlen + 3)
                        keyidx = skb->data[hdrlen + 3] >> 6;

                /* To strip off any security data which appears before the
                 * payload, we simply increase hdrlen (as the header gets
                 * chopped off immediately below). For the security data which
                 * appears after the payload, we use skb_trim. */

                switch (ieee->sec.encode_alg[keyidx]) {
                case SEC_ALG_WEP:
                        /* 4 byte IV */
                        hdrlen += 4;
                        /* 4 byte ICV */
                        trimlen = 4;
                        break;
                case SEC_ALG_TKIP:
                        /* 4 byte IV, 4 byte ExtIV */
                        hdrlen += 8;
                        /* 8 byte MIC, 4 byte ICV */
                        trimlen = 12;
                        break;
                case SEC_ALG_CCMP:
                        /* 8 byte CCMP header */
                        hdrlen += 8;
                        /* 8 byte MIC */
                        trimlen = 8;
                        break;
                }

                if (skb->len < trimlen)
                        goto rx_dropped;

                __skb_trim(skb, skb->len - trimlen);

                if (skb->len < hdrlen)
                        goto rx_dropped;
        }

        /* skb: hdr + (possible reassembled) full plaintext payload */

        payload = skb->data + hdrlen;
        ethertype = (payload[6] << 8) | payload[7];

#ifdef NOT_YET
        /* If IEEE 802.1X is used, check whether the port is authorized to send
         * the received frame. */
        if (ieee->ieee802_1x && ieee->iw_mode == IW_MODE_MASTER) {
                if (ethertype == ETH_P_PAE) {
                        printk(KERN_DEBUG "%s: RX: IEEE 802.1X frame\n",
                               dev->name);
                        if (ieee->hostapd && ieee->apdev) {
                                /* Send IEEE 802.1X frames to the user
                                 * space daemon for processing */
                                prism2_rx_80211(ieee->apdev, skb, rx_stats,
                                                PRISM2_RX_MGMT);
                                ieee->apdevstats.rx_packets++;
                                ieee->apdevstats.rx_bytes += skb->len;
                                goto rx_exit;
                        }
                } else if (!frame_authorized) {
                        printk(KERN_DEBUG "%s: dropped frame from "
                               "unauthorized port (IEEE 802.1X): "
                               "ethertype=0x%04x\n", dev->name, ethertype);
                        goto rx_dropped;
                }
        }
#endif

        /* convert hdr + possible LLC headers into Ethernet header */
        if (skb->len - hdrlen >= 8 &&
            ((memcmp(payload, rfc1042_header, SNAP_SIZE) == 0 &&
              ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
             memcmp(payload, bridge_tunnel_header, SNAP_SIZE) == 0)) {
                /* remove RFC1042 or Bridge-Tunnel encapsulation and
                 * replace EtherType */
                skb_pull(skb, hdrlen + SNAP_SIZE);
                memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
                memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
        } else {
                __be16 len;
                /* Leave Ethernet header part of hdr and full payload */
                skb_pull(skb, hdrlen);
                len = htons(skb->len);
                memcpy(skb_push(skb, 2), &len, 2);
                memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
                memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
        }

#ifdef NOT_YET
        if (wds && ((fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==
                    IEEE80211_FCTL_TODS) && skb->len >= ETH_HLEN + ETH_ALEN) {
                /* Non-standard frame: get addr4 from its bogus location after
                 * the payload */
                skb_copy_to_linear_data_offset(skb, ETH_ALEN,
                                               skb->data + skb->len - ETH_ALEN,
                                               ETH_ALEN);
                skb_trim(skb, skb->len - ETH_ALEN);
        }
#endif

        stats->rx_packets++;
        stats->rx_bytes += skb->len;

#ifdef NOT_YET
        if (ieee->iw_mode == IW_MODE_MASTER && !wds && ieee->ap->bridge_packets) {
                if (dst[0] & 0x01) {
                        /* copy multicast frame both to the higher layers and
                         * to the wireless media */
                        ieee->ap->bridged_multicast++;
                        skb2 = skb_clone(skb, GFP_ATOMIC);
                        if (skb2 == NULL)
                                printk(KERN_DEBUG "%s: skb_clone failed for "
                                       "multicast frame\n", dev->name);
                } else if (hostap_is_sta_assoc(ieee->ap, dst)) {
                        /* send frame directly to the associated STA using
                         * wireless media and not passing to higher layers */
                        ieee->ap->bridged_unicast++;
                        skb2 = skb;
                        skb = NULL;
                }
        }

        if (skb2 != NULL) {
                /* send to wireless media */
                skb2->dev = dev;
                skb2->protocol = htons(ETH_P_802_3);
                skb_reset_mac_header(skb2);
                skb_reset_network_header(skb2);
                /* skb2->network_header += ETH_HLEN; */
                dev_queue_xmit(skb2);
        }
#endif

        if (skb) {
                skb->protocol = eth_type_trans(skb, dev);
                memset(skb->cb, 0, sizeof(skb->cb));
                skb->ip_summed = CHECKSUM_NONE; /* 802.11 crc not sufficient */
                if (netif_rx(skb) == NET_RX_DROP) {
                        /* netif_rx always succeeds, but it might drop
                         * the packet.  If it drops the packet, we log that
                         * in our stats. */
                        IEEE80211_DEBUG_DROP
                            ("RX: netif_rx dropped the packet\n");
                        stats->rx_dropped++;
                }
        }

      rx_exit:
#ifdef NOT_YET
        if (sta)
                hostap_handle_sta_release(sta);
#endif
        return 1;

      rx_dropped:
        stats->rx_dropped++;

        /* Returning 0 indicates to caller that we have not handled the SKB--
         * so it is still allocated and can be used again by underlying
         * hardware as a DMA target */
        return 0;
}

/* Filter out unrelated packets, call ieee80211_rx[_mgt]
 * This function takes over the skb, it should not be used again after calling
 * this function. */
void ieee80211_rx_any(struct ieee80211_device *ieee,
                     struct sk_buff *skb, struct ieee80211_rx_stats *stats)
{
        struct ieee80211_hdr_4addr *hdr;
        int is_packet_for_us;
        u16 fc;

        if (ieee->iw_mode == IW_MODE_MONITOR) {
                if (!ieee80211_rx(ieee, skb, stats))
                        dev_kfree_skb_irq(skb);
                return;
        }

        if (skb->len < sizeof(struct ieee80211_hdr))
                goto drop_free;

        hdr = (struct ieee80211_hdr_4addr *)skb->data;
        fc = le16_to_cpu(hdr->frame_ctl);

        if ((fc & IEEE80211_FCTL_VERS) != 0)
                goto drop_free;

        switch (fc & IEEE80211_FCTL_FTYPE) {
        case IEEE80211_FTYPE_MGMT:
                if (skb->len < sizeof(struct ieee80211_hdr_3addr))
                        goto drop_free;
                ieee80211_rx_mgt(ieee, hdr, stats);
                dev_kfree_skb_irq(skb);
                return;
        case IEEE80211_FTYPE_DATA:
                break;
        case IEEE80211_FTYPE_CTL:
                return;
        default:
                return;
        }

        is_packet_for_us = 0;
        switch (ieee->iw_mode) {
        case IW_MODE_ADHOC:
                /* our BSS and not from/to DS */
                if (memcmp(hdr->addr3, ieee->bssid, ETH_ALEN) == 0)
                if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == 0) {
                        /* promisc: get all */
                        if (ieee->dev->flags & IFF_PROMISC)
                                is_packet_for_us = 1;
                        /* to us */
                        else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
                                is_packet_for_us = 1;
                        /* mcast */
                        else if (is_multicast_ether_addr(hdr->addr1))
                                is_packet_for_us = 1;
                }
                break;
        case IW_MODE_INFRA:
                /* our BSS (== from our AP) and from DS */
                if (memcmp(hdr->addr2, ieee->bssid, ETH_ALEN) == 0)
                if ((fc & (IEEE80211_FCTL_TODS+IEEE80211_FCTL_FROMDS)) == IEEE80211_FCTL_FROMDS) {
                        /* promisc: get all */
                        if (ieee->dev->flags & IFF_PROMISC)
                                is_packet_for_us = 1;
                        /* to us */
                        else if (memcmp(hdr->addr1, ieee->dev->dev_addr, ETH_ALEN) == 0)
                                is_packet_for_us = 1;
                        /* mcast */
                        else if (is_multicast_ether_addr(hdr->addr1)) {
                                /* not our own packet bcasted from AP */
                                if (memcmp(hdr->addr3, ieee->dev->dev_addr, ETH_ALEN))
                                        is_packet_for_us = 1;
                        }
                }
                break;
        default:
                /* ? */
                break;
        }

        if (is_packet_for_us)
                if (!ieee80211_rx(ieee, skb, stats))
                        dev_kfree_skb_irq(skb);
        return;

drop_free:
        dev_kfree_skb_irq(skb);
        ieee->stats.rx_dropped++;
        return;
}

#define MGMT_FRAME_FIXED_PART_LENGTH            0x24

static u8 qos_oui[QOS_OUI_LEN] = { 0x00, 0x50, 0xF2 };

/*
* Make ther structure we read from the beacon packet has
* the right values
*/
static int ieee80211_verify_qos_info(struct ieee80211_qos_information_element
                                     *info_element, int sub_type)
{

        if (info_element->qui_subtype != sub_type)
                return -1;
        if (memcmp(info_element->qui, qos_oui, QOS_OUI_LEN))
                return -1;
        if (info_element->qui_type != QOS_OUI_TYPE)
                return -1;
        if (info_element->version != QOS_VERSION_1)
                return -1;

        return 0;
}

/*
 * Parse a QoS parameter element
 */
static int ieee80211_read_qos_param_element(struct ieee80211_qos_parameter_info
                                            *element_param, struct ieee80211_info_element
                                            *info_element)
{
        int ret = 0;
        u16 size = sizeof(struct ieee80211_qos_parameter_info) - 2;

        if ((info_element == NULL) || (element_param == NULL))
                return -1;

        if (info_element->id == QOS_ELEMENT_ID && info_element->len == size) {
                memcpy(element_param->info_element.qui, info_element->data,
                       info_element->len);
                element_param->info_element.elementID = info_element->id;
                element_param->info_element.length = info_element->len;
        } else
                ret = -1;
        if (ret == 0)
                ret = ieee80211_verify_qos_info(&element_param->info_element,
                                                QOS_OUI_PARAM_SUB_TYPE);
        return ret;
}

/*
 * Parse a QoS information element
 */
static int ieee80211_read_qos_info_element(struct
                                           ieee80211_qos_information_element
                                           *element_info, struct ieee80211_info_element
                                           *info_element)
{
        int ret = 0;
        u16 size = sizeof(struct ieee80211_qos_information_element) - 2;

        if (element_info == NULL)
                return -1;
        if (info_element == NULL)
                return -1;

        if ((info_element->id == QOS_ELEMENT_ID) && (info_element->len == size)) {
                memcpy(element_info->qui, info_element->data,
                       info_element->len);
                element_info->elementID = info_element->id;
                element_info->length = info_element->len;
        } else
                ret = -1;

        if (ret == 0)
                ret = ieee80211_verify_qos_info(element_info,
                                                QOS_OUI_INFO_SUB_TYPE);
        return ret;
}

/*
 * Write QoS parameters from the ac parameters.
 */
static int ieee80211_qos_convert_ac_to_parameters(struct
                                                  ieee80211_qos_parameter_info
                                                  *param_elm, struct
                                                  ieee80211_qos_parameters
                                                  *qos_param)
{
        int rc = 0;
        int i;
        struct ieee80211_qos_ac_parameter *ac_params;
        u32 txop;
        u8 cw_min;
        u8 cw_max;

        for (i = 0; i < QOS_QUEUE_NUM; i++) {
                ac_params = &(param_elm->ac_params_record[i]);

                qos_param->aifs[i] = (ac_params->aci_aifsn) & 0x0F;
                qos_param->aifs[i] -= (qos_param->aifs[i] < 2) ? 0 : 2;

                cw_min = ac_params->ecw_min_max & 0x0F;
                qos_param->cw_min[i] = cpu_to_le16((1 << cw_min) - 1);

                cw_max = (ac_params->ecw_min_max & 0xF0) >> 4;
                qos_param->cw_max[i] = cpu_to_le16((1 << cw_max) - 1);

                qos_param->flag[i] =
                    (ac_params->aci_aifsn & 0x10) ? 0x01 : 0x00;

                txop = le16_to_cpu(ac_params->tx_op_limit) * 32;
                qos_param->tx_op_limit[i] = cpu_to_le16(txop);
        }
        return rc;
}

/*
 * we have a generic data element which it may contain QoS information or
 * parameters element. check the information element length to decide
 * which type to read
 */
static int ieee80211_parse_qos_info_param_IE(struct ieee80211_info_element
                                             *info_element,
                                             struct ieee80211_network *network)
{
        int rc = 0;
        struct ieee80211_qos_parameters *qos_param = NULL;
        struct ieee80211_qos_information_element qos_info_element;

        rc = ieee80211_read_qos_info_element(&qos_info_element, info_element);

        if (rc == 0) {
                network->qos_data.param_count = qos_info_element.ac_info & 0x0F;
                network->flags |= NETWORK_HAS_QOS_INFORMATION;
        } else {
                struct ieee80211_qos_parameter_info param_element;

                rc = ieee80211_read_qos_param_element(&param_element,
                                                      info_element);
                if (rc == 0) {
                        qos_param = &(network->qos_data.parameters);
                        ieee80211_qos_convert_ac_to_parameters(&param_element,
                                                               qos_param);
                        network->flags |= NETWORK_HAS_QOS_PARAMETERS;
                        network->qos_data.param_count =
                            param_element.info_element.ac_info & 0x0F;
                }
        }

        if (rc == 0) {
                IEEE80211_DEBUG_QOS("QoS is supported\n");
                network->qos_data.supported = 1;
        }
        return rc;
}

#ifdef CONFIG_IEEE80211_DEBUG
#define MFIE_STRING(x) case MFIE_TYPE_ ##x: return #x

static const char *get_info_element_string(u16 id)
{
        switch (id) {
                MFIE_STRING(SSID);
                MFIE_STRING(RATES);
                MFIE_STRING(FH_SET);
                MFIE_STRING(DS_SET);
                MFIE_STRING(CF_SET);
                MFIE_STRING(TIM);
                MFIE_STRING(IBSS_SET);
                MFIE_STRING(COUNTRY);
                MFIE_STRING(HOP_PARAMS);
                MFIE_STRING(HOP_TABLE);
                MFIE_STRING(REQUEST);
                MFIE_STRING(CHALLENGE);
                MFIE_STRING(POWER_CONSTRAINT);
                MFIE_STRING(POWER_CAPABILITY);
                MFIE_STRING(TPC_REQUEST);
                MFIE_STRING(TPC_REPORT);
                MFIE_STRING(SUPP_CHANNELS);
                MFIE_STRING(CSA);
                MFIE_STRING(MEASURE_REQUEST);
                MFIE_STRING(MEASURE_REPORT);
                MFIE_STRING(QUIET);
                MFIE_STRING(IBSS_DFS);
                MFIE_STRING(ERP_INFO);
                MFIE_STRING(RSN);
                MFIE_STRING(RATES_EX);
                MFIE_STRING(GENERIC);
                MFIE_STRING(QOS_PARAMETER);
        default:
                return "UNKNOWN";
        }
}
#endif

static int ieee80211_parse_info_param(struct ieee80211_info_element
                                      *info_element, u16 length,
                                      struct ieee80211_network *network)
{
        u8 i;
#ifdef CONFIG_IEEE80211_DEBUG
        char rates_str[64];
        char *p;
#endif

        while (length >= sizeof(*info_element)) {
                if (sizeof(*info_element) + info_element->len > length) {
                        IEEE80211_DEBUG_MGMT("Info elem: parse failed: "
                                             "info_element->len + 2 > left : "
                                             "info_element->len+2=%zd left=%d, id=%d.\n",
                                             info_element->len +
                                             sizeof(*info_element),
                                             length, info_element->id);
                        /* We stop processing but don't return an error here
                         * because some misbehaviour APs break this rule. ie.
                         * Orinoco AP1000. */
                        break;
                }

                switch (info_element->id) {
                case MFIE_TYPE_SSID:
                        if (ieee80211_is_empty_essid(info_element->data,
                                                     info_element->len)) {
                                network->flags |= NETWORK_EMPTY_ESSID;
                                break;
                        }

                        network->ssid_len = min(info_element->len,
                                                (u8) IW_ESSID_MAX_SIZE);
                        memcpy(network->ssid, info_element->data,
                               network->ssid_len);
                        if (network->ssid_len < IW_ESSID_MAX_SIZE)
                                memset(network->ssid + network->ssid_len, 0,
                                       IW_ESSID_MAX_SIZE - network->ssid_len);

                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_SSID: '%s' len=%d.\n",
                                             network->ssid, network->ssid_len);
                        break;

                case MFIE_TYPE_RATES:
#ifdef CONFIG_IEEE80211_DEBUG
                        p = rates_str;
#endif
                        network->rates_len = min(info_element->len,
                                                 MAX_RATES_LENGTH);
                        for (i = 0; i < network->rates_len; i++) {
                                network->rates[i] = info_element->data[i];
#ifdef CONFIG_IEEE80211_DEBUG
                                p += snprintf(p, sizeof(rates_str) -
                                              (p - rates_str), "%02X ",
                                              network->rates[i]);
#endif
                                if (ieee80211_is_ofdm_rate
                                    (info_element->data[i])) {
                                        network->flags |= NETWORK_HAS_OFDM;
                                        if (info_element->data[i] &
                                            IEEE80211_BASIC_RATE_MASK)
                                                network->flags &=
                                                    ~NETWORK_HAS_CCK;
                                }
                        }

                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_RATES: '%s' (%d)\n",
                                             rates_str, network->rates_len);
                        break;

                case MFIE_TYPE_RATES_EX:
#ifdef CONFIG_IEEE80211_DEBUG
                        p = rates_str;
#endif
                        network->rates_ex_len = min(info_element->len,
                                                    MAX_RATES_EX_LENGTH);
                        for (i = 0; i < network->rates_ex_len; i++) {
                                network->rates_ex[i] = info_element->data[i];
#ifdef CONFIG_IEEE80211_DEBUG
                                p += snprintf(p, sizeof(rates_str) -
                                              (p - rates_str), "%02X ",
                                              network->rates[i]);
#endif
                                if (ieee80211_is_ofdm_rate
                                    (info_element->data[i])) {
                                        network->flags |= NETWORK_HAS_OFDM;
                                        if (info_element->data[i] &
                                            IEEE80211_BASIC_RATE_MASK)
                                                network->flags &=
                                                    ~NETWORK_HAS_CCK;
                                }
                        }

                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_RATES_EX: '%s' (%d)\n",
                                             rates_str, network->rates_ex_len);
                        break;

                case MFIE_TYPE_DS_SET:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_DS_SET: %d\n",
                                             info_element->data[0]);
                        network->channel = info_element->data[0];
                        break;

                case MFIE_TYPE_FH_SET:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_FH_SET: ignored\n");
                        break;

                case MFIE_TYPE_CF_SET:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_CF_SET: ignored\n");
                        break;

                case MFIE_TYPE_TIM:
                        network->tim.tim_count = info_element->data[0];
                        network->tim.tim_period = info_element->data[1];
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_TIM: partially ignored\n");
                        break;

                case MFIE_TYPE_ERP_INFO:
                        network->erp_value = info_element->data[0];
                        network->flags |= NETWORK_HAS_ERP_VALUE;
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_ERP_SET: %d\n",
                                             network->erp_value);
                        break;

                case MFIE_TYPE_IBSS_SET:
                        network->atim_window = info_element->data[0];
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_IBSS_SET: %d\n",
                                             network->atim_window);
                        break;

                case MFIE_TYPE_CHALLENGE:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_CHALLENGE: ignored\n");
                        break;

                case MFIE_TYPE_GENERIC:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_GENERIC: %d bytes\n",
                                             info_element->len);
                        if (!ieee80211_parse_qos_info_param_IE(info_element,
                                                               network))
                                break;

                        if (info_element->len >= 4 &&
                            info_element->data[0] == 0x00 &&
                            info_element->data[1] == 0x50 &&
                            info_element->data[2] == 0xf2 &&
                            info_element->data[3] == 0x01) {
                                network->wpa_ie_len = min(info_element->len + 2,
                                                          MAX_WPA_IE_LEN);
                                memcpy(network->wpa_ie, info_element,
                                       network->wpa_ie_len);
                        }
                        break;

                case MFIE_TYPE_RSN:
                        IEEE80211_DEBUG_MGMT("MFIE_TYPE_RSN: %d bytes\n",
                                             info_element->len);
                        network->rsn_ie_len = min(info_element->len + 2,
                                                  MAX_WPA_IE_LEN);
                        memcpy(network->rsn_ie, info_element,
                               network->rsn_ie_len);
                        break;

                case MFIE_TYPE_QOS_PARAMETER:
                        printk(KERN_ERR
                               "QoS Error need to parse QOS_PARAMETER IE\n");
                        break;
                        /* 802.11h */
                case MFIE_TYPE_POWER_CONSTRAINT:
                        network->power_constraint = info_element->data[0];
                        network->flags |= NETWORK_HAS_POWER_CONSTRAINT;
                        break;

                case MFIE_TYPE_CSA:
                        network->power_constraint = info_element->data[0];
                        network->flags |= NETWORK_HAS_CSA;
                        break;

                case MFIE_TYPE_QUIET:
                        network->quiet.count = info_element->data[0];
                        network->quiet.period = info_element->data[1];
                        network->quiet.duration = info_element->data[2];
                        network->quiet.offset = info_element->data[3];
                        network->flags |= NETWORK_HAS_QUIET;
                        break;

                case MFIE_TYPE_IBSS_DFS:
                        if (network->ibss_dfs)
                                break;
                        network->ibss_dfs = kmemdup(info_element->data,
                                                    info_element->len,
                                                    GFP_ATOMIC);
                        if (!network->ibss_dfs)
                                return 1;
                        network->flags |= NETWORK_HAS_IBSS_DFS;
                        break;

                case MFIE_TYPE_TPC_REPORT:
                        network->tpc_report.transmit_power =
                            info_element->data[0];
                        network->tpc_report.link_margin = info_element->data[1];
                        network->flags |= NETWORK_HAS_TPC_REPORT;
                        break;

                default:
                        IEEE80211_DEBUG_MGMT
                            ("Unsupported info element: %s (%d)\n",
                             get_info_element_string(info_element->id),
                             info_element->id);
                        break;
                }

                length -= sizeof(*info_element) + info_element->len;
                info_element =
                    (struct ieee80211_info_element *)&info_element->
                    data[info_element->len];
        }

        return 0;
}

static int ieee80211_handle_assoc_resp(struct ieee80211_device *ieee, struct ieee80211_assoc_response
                                       *frame, struct ieee80211_rx_stats *stats)
{
        struct ieee80211_network network_resp = {
                .ibss_dfs = NULL,
        };
        struct ieee80211_network *network = &network_resp;
        struct net_device *dev = ieee->dev;

        network->flags = 0;
        network->qos_data.active = 0;
        network->qos_data.supported = 0;
        network->qos_data.param_count = 0;
        network->qos_data.old_param_count = 0;

        //network->atim_window = le16_to_cpu(frame->aid) & (0x3FFF);
        network->atim_window = le16_to_cpu(frame->aid);
        network->listen_interval = le16_to_cpu(frame->status);
        memcpy(network->bssid, frame->header.addr3, ETH_ALEN);
        network->capability = le16_to_cpu(frame->capability);
        network->last_scanned = jiffies;
        network->rates_len = network->rates_ex_len = 0;
        network->last_associate = 0;
        network->ssid_len = 0;
        network->erp_value =
            (network->capability & WLAN_CAPABILITY_IBSS) ? 0x3 : 0x0;

        if (stats->freq == IEEE80211_52GHZ_BAND) {
                /* for A band (No DS info) */
                network->channel = stats->received_channel;
        } else
                network->flags |= NETWORK_HAS_CCK;

        network->wpa_ie_len = 0;
        network->rsn_ie_len = 0;

        if (ieee80211_parse_info_param
            (frame->info_element, stats->len - sizeof(*frame), network))
                return 1;

        network->mode = 0;
        if (stats->freq == IEEE80211_52GHZ_BAND)
                network->mode = IEEE_A;
        else {
                if (network->flags & NETWORK_HAS_OFDM)
                        network->mode |= IEEE_G;
                if (network->flags & NETWORK_HAS_CCK)
                        network->mode |= IEEE_B;
        }

        if (ieee80211_is_empty_essid(network->ssid, network->ssid_len))
                network->flags |= NETWORK_EMPTY_ESSID;

        memcpy(&network->stats, stats, sizeof(network->stats));

        if (ieee->handle_assoc_response != NULL)
                ieee->handle_assoc_response(dev, frame, network);

        return 0;
}

/***************************************************/

static int ieee80211_network_init(struct ieee80211_device *ieee, struct ieee80211_probe_response
                                         *beacon,
                                         struct ieee80211_network *network,
                                         struct ieee80211_rx_stats *stats)
{
        DECLARE_MAC_BUF(mac);

        network->qos_data.active = 0;
        network->qos_data.supported = 0;
        network->qos_data.param_count = 0;
        network->qos_data.old_param_count = 0;

        /* Pull out fixed field data */
        memcpy(network->bssid, beacon->header.addr3, ETH_ALEN);
        network->capability = le16_to_cpu(beacon->capability);
        network->last_scanned = jiffies;
        network->time_stamp[0] = le32_to_cpu(beacon->time_stamp[0]);
        network->time_stamp[1] = le32_to_cpu(beacon->time_stamp[1]);
        network->beacon_interval = le16_to_cpu(beacon->beacon_interval);
        /* Where to pull this? beacon->listen_interval; */
        network->listen_interval = 0x0A;
        network->rates_len = network->rates_ex_len = 0;
        network->last_associate = 0;
        network->ssid_len = 0;
        network->flags = 0;
        network->atim_window = 0;
        network->erp_value = (network->capability & WLAN_CAPABILITY_IBSS) ?
            0x3 : 0x0;

        if (stats->freq == IEEE80211_52GHZ_BAND) {
                /* for A band (No DS info) */
                network->channel = stats->received_channel;
        } else
                network->flags |= NETWORK_HAS_CCK;

        network->wpa_ie_len = 0;
        network->rsn_ie_len = 0;

        if (ieee80211_parse_info_param
            (beacon->info_element, stats->len - sizeof(*beacon), network))
                return 1;

        network->mode = 0;
        if (stats->freq == IEEE80211_52GHZ_BAND)
                network->mode = IEEE_A;
        else {
                if (network->flags & NETWORK_HAS_OFDM)
                        network->mode |= IEEE_G;
                if (network->flags & NETWORK_HAS_CCK)
                        network->mode |= IEEE_B;
        }

        if (network->mode == 0) {
                IEEE80211_DEBUG_SCAN("Filtered out '%s (%s)' "
                                     "network.\n",
                                     escape_essid(network->ssid,
                                                  network->ssid_len),
                                     print_mac(mac, network->bssid));
                return 1;
        }

        if (ieee80211_is_empty_essid(network->ssid, network->ssid_len))
                network->flags |= NETWORK_EMPTY_ESSID;

        memcpy(&network->stats, stats, sizeof(network->stats));

        return 0;
}

static inline int is_same_network(struct ieee80211_network *src,
                                  struct ieee80211_network *dst)
{
        /* A network is only a duplicate if the channel, BSSID, and ESSID
         * all match.  We treat all <hidden> with the same BSSID and channel
         * as one network */
        return ((src->ssid_len == dst->ssid_len) &&
                (src->channel == dst->channel) &&
                !compare_ether_addr(src->bssid, dst->bssid) &&
                !memcmp(src->ssid, dst->ssid, src->ssid_len));
}

static void update_network(struct ieee80211_network *dst,
                                  struct ieee80211_network *src)
{
        int qos_active;
        u8 old_param;
        DECLARE_MAC_BUF(mac);

        ieee80211_network_reset(dst);
        dst->ibss_dfs = src->ibss_dfs;

        /* We only update the statistics if they were created by receiving
         * the network information on the actual channel the network is on.
         *
         * This keeps beacons received on neighbor channels from bringing
         * down the signal level of an AP. */
        if (dst->channel == src->stats.received_channel)
                memcpy(&dst->stats, &src->stats,
                       sizeof(struct ieee80211_rx_stats));
        else
                IEEE80211_DEBUG_SCAN("Network %s info received "
                        "off channel (%d vs. %d)\n", print_mac(mac, src->bssid),
                        dst->channel, src->stats.received_channel);

        dst->capability = src->capability;
        memcpy(dst->rates, src->rates, src->rates_len);
        dst->rates_len = src->rates_len;
        memcpy(dst->rates_ex, src->rates_ex, src->rates_ex_len);
        dst->rates_ex_len = src->rates_ex_len;

        dst->mode = src->mode;
        dst->flags = src->flags;
        dst->time_stamp[0] = src->time_stamp[0];
        dst->time_stamp[1] = src->time_stamp[1];

        dst->beacon_interval = src->beacon_interval;
        dst->listen_interval = src->listen_interval;
        dst->atim_window = src->atim_window;
        dst->erp_value = src->erp_value;
        dst->tim = src->tim;

        memcpy(dst->wpa_ie, src->wpa_ie, src->wpa_ie_len);
        dst->wpa_ie_len = src->wpa_ie_len;
        memcpy(dst->rsn_ie, src->rsn_ie, src->rsn_ie_len);
        dst->rsn_ie_len = src->rsn_ie_len;

        dst->last_scanned = jiffies;
        qos_active = src->qos_data.active;
        old_param = dst->qos_data.old_param_count;
        if (dst->flags & NETWORK_HAS_QOS_MASK)
                memcpy(&dst->qos_data, &src->qos_data,
                       sizeof(struct ieee80211_qos_data));
        else {
                dst->qos_data.supported = src->qos_data.supported;
                dst->qos_data.param_count = src->qos_data.param_count;
        }

        if (dst->qos_data.supported == 1) {
                if (dst->ssid_len)
                        IEEE80211_DEBUG_QOS
                            ("QoS the network %s is QoS supported\n",
                             dst->ssid);
                else
                        IEEE80211_DEBUG_QOS
                            ("QoS the network is QoS supported\n");
        }
        dst->qos_data.active = qos_active;
        dst->qos_data.old_param_count = old_param;

        /* dst->last_associate is not overwritten */
}

static inline int is_beacon(__le16 fc)
{
        return (WLAN_FC_GET_STYPE(le16_to_cpu(fc)) == IEEE80211_STYPE_BEACON);
}

static void ieee80211_process_probe_response(struct ieee80211_device
                                                    *ieee, struct
                                                    ieee80211_probe_response
                                                    *beacon, struct ieee80211_rx_stats
                                                    *stats)
{
        struct net_device *dev = ieee->dev;
        struct ieee80211_network network = {
                .ibss_dfs = NULL,
        };
        struct ieee80211_network *target;
        struct ieee80211_network *oldest = NULL;
#ifdef CONFIG_IEEE80211_DEBUG
        struct ieee80211_info_element *info_element = beacon->info_element;
#endif
        unsigned long flags;
        DECLARE_MAC_BUF(mac);

        IEEE80211_DEBUG_SCAN("'%s' (%s"
                     "): %c%c%c%c %c%c%c%c-%c%c%c%c %c%c%c%c\n",
                     escape_essid(info_element->data, info_element->len),
                     print_mac(mac, beacon->header.addr3),
                     (beacon->capability & cpu_to_le16(1 << 0xf)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0xe)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0xd)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0xc)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0xb)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0xa)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x9)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x8)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x7)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x6)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x5)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x4)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x3)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x2)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x1)) ? '1' : '0',
                     (beacon->capability & cpu_to_le16(1 << 0x0)) ? '1' : '0');

        if (ieee80211_network_init(ieee, beacon, &network, stats)) {
                IEEE80211_DEBUG_SCAN("Dropped '%s' (%s) via %s.\n",
                                     escape_essid(info_element->data,
                                                  info_element->len),
                                     print_mac(mac, beacon->header.addr3),
                                     is_beacon(beacon->header.frame_ctl) ?
                                     "BEACON" : "PROBE RESPONSE");
                return;
        }

        /* The network parsed correctly -- so now we scan our known networks
         * to see if we can find it in our list.
         *
         * NOTE:  This search is definitely not optimized.  Once its doing
         *        the "right thing" we'll optimize it for efficiency if
         *        necessary */

        /* Search for this entry in the list and update it if it is
         * already there. */

        spin_lock_irqsave(&ieee->lock, flags);

        list_for_each_entry(target, &ieee->network_list, list) {
                if (is_same_network(target, &network))
                        break;

                if ((oldest == NULL) ||
                    (target->last_scanned < oldest->last_scanned))
                        oldest = target;
        }

        /* If we didn't find a match, then get a new network slot to initialize
         * with this beacon's information */
        if (&target->list == &ieee->network_list) {
                if (list_empty(&ieee->network_free_list)) {
                        /* If there are no more slots, expire the oldest */
                        list_del(&oldest->list);
                        target = oldest;
                        IEEE80211_DEBUG_SCAN("Expired '%s' (%s) from "
                                             "network list.\n",
                                             escape_essid(target->ssid,
                                                          target->ssid_len),
                                             print_mac(mac, target->bssid));
                        ieee80211_network_reset(target);
                } else {
                        /* Otherwise just pull from the free list */
                        target = list_entry(ieee->network_free_list.next,
                                            struct ieee80211_network, list);
                        list_del(ieee->network_free_list.next);
                }

#ifdef CONFIG_IEEE80211_DEBUG
                IEEE80211_DEBUG_SCAN("Adding '%s' (%s) via %s.\n",
                                     escape_essid(network.ssid,
                                                  network.ssid_len),
                                     print_mac(mac, network.bssid),
                                     is_beacon(beacon->header.frame_ctl) ?
                                     "BEACON" : "PROBE RESPONSE");
#endif
                memcpy(target, &network, sizeof(*target));
                network.ibss_dfs = NULL;
                list_add_tail(&target->list, &ieee->network_list);
        } else {
                IEEE80211_DEBUG_SCAN("Updating '%s' (%s) via %s.\n",
                                     escape_essid(target->ssid,
                                                  target->ssid_len),
                                     print_mac(mac, target->bssid),
                                     is_beacon(beacon->header.frame_ctl) ?
                                     "BEACON" : "PROBE RESPONSE");
                update_network(target, &network);
                network.ibss_dfs = NULL;
        }

        spin_unlock_irqrestore(&ieee->lock, flags);

        if (is_beacon(beacon->header.frame_ctl)) {
                if (ieee->handle_beacon != NULL)
                        ieee->handle_beacon(dev, beacon, target);
        } else {
                if (ieee->handle_probe_response != NULL)
                        ieee->handle_probe_response(dev, beacon, target);
        }
}

void ieee80211_rx_mgt(struct ieee80211_device *ieee,
                      struct ieee80211_hdr_4addr *header,
                      struct ieee80211_rx_stats *stats)
{
        switch (WLAN_FC_GET_STYPE(le16_to_cpu(header->frame_ctl))) {
        case IEEE80211_STYPE_ASSOC_RESP:
                IEEE80211_DEBUG_MGMT("received ASSOCIATION RESPONSE (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                ieee80211_handle_assoc_resp(ieee,
                                            (struct ieee80211_assoc_response *)
                                            header, stats);
                break;

        case IEEE80211_STYPE_REASSOC_RESP:
                IEEE80211_DEBUG_MGMT("received REASSOCIATION RESPONSE (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                break;

        case IEEE80211_STYPE_PROBE_REQ:
                IEEE80211_DEBUG_MGMT("received auth (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));

                if (ieee->handle_probe_request != NULL)
                        ieee->handle_probe_request(ieee->dev,
                                                   (struct
                                                    ieee80211_probe_request *)
                                                   header, stats);
                break;

        case IEEE80211_STYPE_PROBE_RESP:
                IEEE80211_DEBUG_MGMT("received PROBE RESPONSE (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                IEEE80211_DEBUG_SCAN("Probe response\n");
                ieee80211_process_probe_response(ieee,
                                                 (struct
                                                  ieee80211_probe_response *)
                                                 header, stats);
                break;

        case IEEE80211_STYPE_BEACON:
                IEEE80211_DEBUG_MGMT("received BEACON (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                IEEE80211_DEBUG_SCAN("Beacon\n");
                ieee80211_process_probe_response(ieee,
                                                 (struct
                                                  ieee80211_probe_response *)
                                                 header, stats);
                break;
        case IEEE80211_STYPE_AUTH:

                IEEE80211_DEBUG_MGMT("received auth (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));

                if (ieee->handle_auth != NULL)
                        ieee->handle_auth(ieee->dev,
                                          (struct ieee80211_auth *)header);
                break;

        case IEEE80211_STYPE_DISASSOC:
                if (ieee->handle_disassoc != NULL)
                        ieee->handle_disassoc(ieee->dev,
                                              (struct ieee80211_disassoc *)
                                              header);
                break;

        case IEEE80211_STYPE_ACTION:
                IEEE80211_DEBUG_MGMT("ACTION\n");
                if (ieee->handle_action)
                        ieee->handle_action(ieee->dev,
                                            (struct ieee80211_action *)
                                            header, stats);
                break;

        case IEEE80211_STYPE_REASSOC_REQ:
                IEEE80211_DEBUG_MGMT("received reassoc (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));

                IEEE80211_DEBUG_MGMT("%s: IEEE80211_REASSOC_REQ received\n",
                                     ieee->dev->name);
                if (ieee->handle_reassoc_request != NULL)
                        ieee->handle_reassoc_request(ieee->dev,
                                                    (struct ieee80211_reassoc_request *)
                                                     header);
                break;

        case IEEE80211_STYPE_ASSOC_REQ:
                IEEE80211_DEBUG_MGMT("received assoc (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));

                IEEE80211_DEBUG_MGMT("%s: IEEE80211_ASSOC_REQ received\n",
                                     ieee->dev->name);
                if (ieee->handle_assoc_request != NULL)
                        ieee->handle_assoc_request(ieee->dev);
                break;

        case IEEE80211_STYPE_DEAUTH:
                IEEE80211_DEBUG_MGMT("DEAUTH\n");
                if (ieee->handle_deauth != NULL)
                        ieee->handle_deauth(ieee->dev,
                                            (struct ieee80211_deauth *)
                                            header);
                break;
        default:
                IEEE80211_DEBUG_MGMT("received UNKNOWN (%d)\n",
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                IEEE80211_DEBUG_MGMT("%s: Unknown management packet: %d\n",
                                     ieee->dev->name,
                                     WLAN_FC_GET_STYPE(le16_to_cpu
                                                       (header->frame_ctl)));
                break;
        }
}

EXPORT_SYMBOL_GPL(ieee80211_rx_any);
EXPORT_SYMBOL(ieee80211_rx_mgt);
EXPORT_SYMBOL(ieee80211_rx);

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