ibss.c

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/*
 * Some IBSS support code for cfg80211.
 *
 * Copyright 2009   Johannes Berg <[email protected]>
 */

#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/cfg80211.h>
#include "wext-compat.h"
#include "nl80211.h"


void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_bss *bss;
#ifdef CONFIG_CFG80211_WEXT
    union iwreq_data wrqu;
#endif

    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return;

    if (!wdev->ssid_len)
        return;

    bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid,
                   wdev->ssid, wdev->ssid_len,
                   WLAN_CAPABILITY_IBSS, WLAN_CAPABILITY_IBSS);

    if (WARN_ON(!bss))
        return;

    if (wdev->current_bss) {
        cfg80211_unhold_bss(wdev->current_bss);
        cfg80211_put_bss(&wdev->current_bss->pub);
    }

    cfg80211_hold_bss(bss_from_pub(bss));
    wdev->current_bss = bss_from_pub(bss);

    wdev->sme_state = CFG80211_SME_CONNECTED;
    cfg80211_upload_connect_keys(wdev);

    nl80211_send_ibss_bssid(wiphy_to_dev(wdev->wiphy), dev, bssid,
                GFP_KERNEL);
#ifdef CONFIG_CFG80211_WEXT
    memset(&wrqu, 0, sizeof(wrqu));
    memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
    wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
#endif
}

void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
    struct cfg80211_event *ev;
    unsigned long flags;

    CFG80211_DEV_WARN_ON(wdev->sme_state != CFG80211_SME_CONNECTING);

    ev = kzalloc(sizeof(*ev), gfp);
    if (!ev)
        return;

    ev->type = EVENT_IBSS_JOINED;
    memcpy(ev->cr.bssid, bssid, ETH_ALEN);

    spin_lock_irqsave(&wdev->event_lock, flags);
    list_add_tail(&ev->list, &wdev->event_list);
    spin_unlock_irqrestore(&wdev->event_lock, flags);
    queue_work(cfg80211_wq, &rdev->event_work);
}
EXPORT_SYMBOL(cfg80211_ibss_joined);

int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
             struct net_device *dev,
             struct cfg80211_ibss_params *params,
             struct cfg80211_cached_keys *connkeys)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    int err;

    ASSERT_WDEV_LOCK(wdev);

    if (wdev->ssid_len)
        return -EALREADY;

    if (!params->basic_rates) {
        /*
        * If no rates were explicitly configured,
        * use the mandatory rate set for 11b or
        * 11a for maximum compatibility.
        */
        struct ieee80211_supported_band *sband =
            rdev->wiphy.bands[params->channel->band];
        int j;
        u32 flag = params->channel->band == IEEE80211_BAND_5GHZ ?
            IEEE80211_RATE_MANDATORY_A :
            IEEE80211_RATE_MANDATORY_B;

        for (j = 0; j < sband->n_bitrates; j++) {
            if (sband->bitrates[j].flags & flag)
                params->basic_rates |= BIT(j);
        }
    }

    if (WARN_ON(wdev->connect_keys))
        kfree(wdev->connect_keys);
    wdev->connect_keys = connkeys;

    wdev->ibss_fixed = params->channel_fixed;
#ifdef CONFIG_CFG80211_WEXT
    wdev->wext.ibss.channel = params->channel;
#endif
    wdev->sme_state = CFG80211_SME_CONNECTING;

    err = cfg80211_can_use_chan(rdev, wdev, params->channel,
                    params->channel_fixed
                    ? CHAN_MODE_SHARED
                    : CHAN_MODE_EXCLUSIVE);
    if (err) {
        wdev->connect_keys = NULL;
        return err;
    }

    err = rdev->ops->join_ibss(&rdev->wiphy, dev, params);
    if (err) {
        wdev->connect_keys = NULL;
        wdev->sme_state = CFG80211_SME_IDLE;
        return err;
    }

    memcpy(wdev->ssid, params->ssid, params->ssid_len);
    wdev->ssid_len = params->ssid_len;

    return 0;
}

int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
               struct net_device *dev,
               struct cfg80211_ibss_params *params,
               struct cfg80211_cached_keys *connkeys)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    int err;

    mutex_lock(&rdev->devlist_mtx);
    wdev_lock(wdev);
    err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
    wdev_unlock(wdev);
    mutex_unlock(&rdev->devlist_mtx);

    return err;
}

static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
    int i;

    ASSERT_WDEV_LOCK(wdev);

    kfree(wdev->connect_keys);
    wdev->connect_keys = NULL;

    /*
     * Delete all the keys ... pairwise keys can't really
     * exist any more anyway, but default keys might.
     */
    if (rdev->ops->del_key)
        for (i = 0; i < 6; i++)
            rdev->ops->del_key(wdev->wiphy, dev, i, false, NULL);

    if (wdev->current_bss) {
        cfg80211_unhold_bss(wdev->current_bss);
        cfg80211_put_bss(&wdev->current_bss->pub);
    }

    wdev->current_bss = NULL;
    wdev->sme_state = CFG80211_SME_IDLE;
    wdev->ssid_len = 0;
#ifdef CONFIG_CFG80211_WEXT
    if (!nowext)
        wdev->wext.ibss.ssid_len = 0;
#endif
}

void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;

    wdev_lock(wdev);
    __cfg80211_clear_ibss(dev, nowext);
    wdev_unlock(wdev);
}

int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
              struct net_device *dev, bool nowext)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    int err;

    ASSERT_WDEV_LOCK(wdev);

    if (!wdev->ssid_len)
        return -ENOLINK;

    err = rdev->ops->leave_ibss(&rdev->wiphy, dev);

    if (err)
        return err;

    __cfg80211_clear_ibss(dev, nowext);

    return 0;
}

int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
            struct net_device *dev, bool nowext)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    int err;

    wdev_lock(wdev);
    err = __cfg80211_leave_ibss(rdev, dev, nowext);
    wdev_unlock(wdev);

    return err;
}

#ifdef CONFIG_CFG80211_WEXT
int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
                struct wireless_dev *wdev)
{
    struct cfg80211_cached_keys *ck = NULL;
    enum ieee80211_band band;
    int i, err;

    ASSERT_WDEV_LOCK(wdev);

    if (!wdev->wext.ibss.beacon_interval)
        wdev->wext.ibss.beacon_interval = 100;

    /* try to find an IBSS channel if none requested ... */
    if (!wdev->wext.ibss.channel) {
        for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
            struct ieee80211_supported_band *sband;
            struct ieee80211_channel *chan;

            sband = rdev->wiphy.bands[band];
            if (!sband)
                continue;

            for (i = 0; i < sband->n_channels; i++) {
                chan = &sband->channels[i];
                if (chan->flags & IEEE80211_CHAN_NO_IBSS)
                    continue;
                if (chan->flags & IEEE80211_CHAN_DISABLED)
                    continue;
                wdev->wext.ibss.channel = chan;
                break;
            }

            if (wdev->wext.ibss.channel)
                break;
        }

        if (!wdev->wext.ibss.channel)
            return -EINVAL;
    }

    /* don't join -- SSID is not there */
    if (!wdev->wext.ibss.ssid_len)
        return 0;

    if (!netif_running(wdev->netdev))
        return 0;

    if (wdev->wext.keys) {
        wdev->wext.keys->def = wdev->wext.default_key;
        wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
    }

    wdev->wext.ibss.privacy = wdev->wext.default_key != -1;

    if (wdev->wext.keys) {
        ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
        if (!ck)
            return -ENOMEM;
        for (i = 0; i < 6; i++)
            ck->params[i].key = ck->data[i];
    }
    err = __cfg80211_join_ibss(rdev, wdev->netdev,
                   &wdev->wext.ibss, ck);
    if (err)
        kfree(ck);

    return err;
}

int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
                   struct iw_request_info *info,
                   struct iw_freq *wextfreq, char *extra)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
    struct ieee80211_channel *chan = NULL;
    int err, freq;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    if (!rdev->ops->join_ibss)
        return -EOPNOTSUPP;

    freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
    if (freq < 0)
        return freq;

    if (freq) {
        chan = ieee80211_get_channel(wdev->wiphy, freq);
        if (!chan)
            return -EINVAL;
        if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
            chan->flags & IEEE80211_CHAN_DISABLED)
            return -EINVAL;
    }

    if (wdev->wext.ibss.channel == chan)
        return 0;

    wdev_lock(wdev);
    err = 0;
    if (wdev->ssid_len)
        err = __cfg80211_leave_ibss(rdev, dev, true);
    wdev_unlock(wdev);

    if (err)
        return err;

    if (chan) {
        wdev->wext.ibss.channel = chan;
        wdev->wext.ibss.channel_fixed = true;
    } else {
        /* cfg80211_ibss_wext_join will pick one if needed */
        wdev->wext.ibss.channel_fixed = false;
    }

    mutex_lock(&rdev->devlist_mtx);
    wdev_lock(wdev);
    err = cfg80211_ibss_wext_join(rdev, wdev);
    wdev_unlock(wdev);
    mutex_unlock(&rdev->devlist_mtx);

    return err;
}

int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
                   struct iw_request_info *info,
                   struct iw_freq *freq, char *extra)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct ieee80211_channel *chan = NULL;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    wdev_lock(wdev);
    if (wdev->current_bss)
        chan = wdev->current_bss->pub.channel;
    else if (wdev->wext.ibss.channel)
        chan = wdev->wext.ibss.channel;
    wdev_unlock(wdev);

    if (chan) {
        freq->m = chan->center_freq;
        freq->e = 6;
        return 0;
    }

    /* no channel if not joining */
    return -EINVAL;
}

int cfg80211_ibss_wext_siwessid(struct net_device *dev,
                struct iw_request_info *info,
                struct iw_point *data, char *ssid)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
    size_t len = data->length;
    int err;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    if (!rdev->ops->join_ibss)
        return -EOPNOTSUPP;

    wdev_lock(wdev);
    err = 0;
    if (wdev->ssid_len)
        err = __cfg80211_leave_ibss(rdev, dev, true);
    wdev_unlock(wdev);

    if (err)
        return err;

    /* iwconfig uses nul termination in SSID.. */
    if (len > 0 && ssid[len - 1] == '\0')
        len--;

    wdev->wext.ibss.ssid = wdev->ssid;
    memcpy(wdev->wext.ibss.ssid, ssid, len);
    wdev->wext.ibss.ssid_len = len;

    mutex_lock(&rdev->devlist_mtx);
    wdev_lock(wdev);
    err = cfg80211_ibss_wext_join(rdev, wdev);
    wdev_unlock(wdev);
    mutex_unlock(&rdev->devlist_mtx);

    return err;
}

int cfg80211_ibss_wext_giwessid(struct net_device *dev,
                struct iw_request_info *info,
                struct iw_point *data, char *ssid)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    data->flags = 0;

    wdev_lock(wdev);
    if (wdev->ssid_len) {
        data->flags = 1;
        data->length = wdev->ssid_len;
        memcpy(ssid, wdev->ssid, data->length);
    } else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
        data->flags = 1;
        data->length = wdev->wext.ibss.ssid_len;
        memcpy(ssid, wdev->wext.ibss.ssid, data->length);
    }
    wdev_unlock(wdev);

    return 0;
}

int cfg80211_ibss_wext_siwap(struct net_device *dev,
                 struct iw_request_info *info,
                 struct sockaddr *ap_addr, char *extra)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;
    struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
    u8 *bssid = ap_addr->sa_data;
    int err;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    if (!rdev->ops->join_ibss)
        return -EOPNOTSUPP;

    if (ap_addr->sa_family != ARPHRD_ETHER)
        return -EINVAL;

    /* automatic mode */
    if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
        bssid = NULL;

    /* both automatic */
    if (!bssid && !wdev->wext.ibss.bssid)
        return 0;

    /* fixed already - and no change */
    if (wdev->wext.ibss.bssid && bssid &&
        ether_addr_equal(bssid, wdev->wext.ibss.bssid))
        return 0;

    wdev_lock(wdev);
    err = 0;
    if (wdev->ssid_len)
        err = __cfg80211_leave_ibss(rdev, dev, true);
    wdev_unlock(wdev);

    if (err)
        return err;

    if (bssid) {
        memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
        wdev->wext.ibss.bssid = wdev->wext.bssid;
    } else
        wdev->wext.ibss.bssid = NULL;

    mutex_lock(&rdev->devlist_mtx);
    wdev_lock(wdev);
    err = cfg80211_ibss_wext_join(rdev, wdev);
    wdev_unlock(wdev);
    mutex_unlock(&rdev->devlist_mtx);

    return err;
}

int cfg80211_ibss_wext_giwap(struct net_device *dev,
                 struct iw_request_info *info,
                 struct sockaddr *ap_addr, char *extra)
{
    struct wireless_dev *wdev = dev->ieee80211_ptr;

    /* call only for ibss! */
    if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
        return -EINVAL;

    ap_addr->sa_family = ARPHRD_ETHER;

    wdev_lock(wdev);
    if (wdev->current_bss)
        memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
    else if (wdev->wext.ibss.bssid)
        memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
    else
        memset(ap_addr->sa_data, 0, ETH_ALEN);

    wdev_unlock(wdev);

    return 0;
}
#endif