linux/net/wireless/ibss.c
Johannes Berg 5fe231e873 cfg80211: vastly simplify locking
Virtually all code paths in cfg80211 already (need to) hold
the RTNL. As such, there's little point in having another
four mutexes for various parts of the code, they just cause
lock ordering issues (and much of the time, the RTNL and a
few of the others need thus be held.)

Simplify all this by getting rid of the extra four mutexes
and just use the RTNL throughout. Only a few code changes
were needed to do this and we can get rid of a work struct
for bonus points.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-05-25 00:02:15 +02:00

543 lines
12 KiB
C

/*
* Some IBSS support code for cfg80211.
*
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
*/
#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"
#include "rdev-ops.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->wiphy, &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;
trace_cfg80211_ibss_joined(dev, bssid);
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->chandef.chan->band];
int j;
u32 flag = params->chandef.chan->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.chandef = params->chandef;
#endif
wdev->sme_state = CFG80211_SME_CONNECTING;
err = cfg80211_can_use_chan(rdev, wdev, params->chandef.chan,
params->channel_fixed
? CHAN_MODE_SHARED
: CHAN_MODE_EXCLUSIVE);
if (err) {
wdev->connect_keys = NULL;
return err;
}
err = rdev_join_ibss(rdev, 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;
ASSERT_RTNL();
wdev_lock(wdev);
err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
wdev_unlock(wdev);
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_del_key(rdev, dev, i, false, NULL);
if (wdev->current_bss) {
cfg80211_unhold_bss(wdev->current_bss);
cfg80211_put_bss(wdev->wiphy, &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_leave_ibss(rdev, 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.chandef.chan) {
wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
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.chandef.chan = chan;
break;
}
if (wdev->wext.ibss.chandef.chan)
break;
}
if (!wdev->wext.ibss.chandef.chan)
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.chandef.chan == 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.chandef.chan = chan;
wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
wdev->wext.ibss.channel_fixed = true;
} else {
/* cfg80211_ibss_wext_join will pick one if needed */
wdev->wext.ibss.channel_fixed = false;
}
wdev_lock(wdev);
err = cfg80211_ibss_wext_join(rdev, wdev);
wdev_unlock(wdev);
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.chandef.chan)
chan = wdev->wext.ibss.chandef.chan;
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;
wdev_lock(wdev);
err = cfg80211_ibss_wext_join(rdev, wdev);
wdev_unlock(wdev);
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;
wdev_lock(wdev);
err = cfg80211_ibss_wext_join(rdev, wdev);
wdev_unlock(wdev);
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