linux/net/wireless/wext-sme.c
Johannes Berg f444de05d2 cfg80211/mac80211: better channel handling
Currently (all tested with hwsim) you can do stupid
things like setting up an AP on a certain channel,
then adding another virtual interface and making
that associate on another channel -- this will make
the beaconing to move channel but obviously without
the necessary IEs data update.

In order to improve this situation, first make the
configuration APIs (cfg80211 and nl80211) aware of
multi-channel operation -- we'll eventually need
that in the future anyway. There's one userland API
change and one API addition. The API change is that
now SET_WIPHY must be called with virtual interface
index rather than only wiphy index in order to take
effect for that interface -- luckily all current
users (hostapd) do that. For monitor interfaces, the
old setting is preserved, but monitors are always
slaved to other devices anyway so no guarantees.

The second userland API change is the introduction
of a per virtual interface SET_CHANNEL command, that
hostapd should use going forward to make it easier
to understand what's going on (it can automatically
detect a kernel with this command).

Other than mac80211, no existing cfg80211 drivers
are affected by this change because they only allow
a single virtual interface.

mac80211, however, now needs to be aware that the
channel settings are per interface now, and needs
to disallow (for now) real multi-channel operation,
which is another important part of this patch.

One of the immediate benefits is that you can now
start hostapd to operate on a hardware that already
has a connection on another virtual interface, as
long as you specify the same channel.

Note that two things are left unhandled (this is an
improvement -- not a complete fix):

 * different HT/no-HT modes

   currently you could start an HT AP and then
   connect to a non-HT network on the same channel
   which would configure the hardware for no HT;
   that can be fixed fairly easily

 * CSA

   An AP we're connected to on a virtual interface
   might indicate switching channels, and in that
   case we would follow it, regardless of how many
   other interfaces are operating; this requires
   more effort to fix but is pretty rare after all

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-05-07 14:55:50 -04:00

403 lines
9.1 KiB
C

/*
* cfg80211 wext compat for managed mode.
*
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
* Copyright (C) 2009 Intel Corporation. All rights reserved.
*/
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <net/cfg80211.h>
#include "wext-compat.h"
#include "nl80211.h"
int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,
struct wireless_dev *wdev)
{
struct cfg80211_cached_keys *ck = NULL;
const u8 *prev_bssid = NULL;
int err, i;
ASSERT_RDEV_LOCK(rdev);
ASSERT_WDEV_LOCK(wdev);
if (!netif_running(wdev->netdev))
return 0;
wdev->wext.connect.ie = wdev->wext.ie;
wdev->wext.connect.ie_len = wdev->wext.ie_len;
if (wdev->wext.keys) {
wdev->wext.keys->def = wdev->wext.default_key;
wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
if (wdev->wext.default_key != -1)
wdev->wext.connect.privacy = true;
}
if (!wdev->wext.connect.ssid_len)
return 0;
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];
}
if (wdev->wext.prev_bssid_valid)
prev_bssid = wdev->wext.prev_bssid;
err = __cfg80211_connect(rdev, wdev->netdev,
&wdev->wext.connect, ck, prev_bssid);
if (err)
kfree(ck);
return err;
}
int cfg80211_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
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_DISABLED)
return -EINVAL;
}
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
wdev_lock(wdev);
if (wdev->sme_state != CFG80211_SME_IDLE) {
bool event = true;
if (wdev->wext.connect.channel == chan) {
err = 0;
goto out;
}
/* if SSID set, we'll try right again, avoid event */
if (wdev->wext.connect.ssid_len)
event = false;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, event);
if (err)
goto out;
}
wdev->wext.connect.channel = chan;
/* SSID is not set, we just want to switch channel */
if (chan && !wdev->wext.connect.ssid_len) {
err = cfg80211_set_freq(rdev, wdev, freq, NL80211_CHAN_NO_HT);
goto out;
}
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
wdev_lock(wdev);
if (wdev->current_bss)
chan = wdev->current_bss->pub.channel;
else if (wdev->wext.connect.channel)
chan = wdev->wext.connect.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_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
if (!data->flags)
len = 0;
/* iwconfig uses nul termination in SSID.. */
if (len > 0 && ssid[len - 1] == '\0')
len--;
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
wdev_lock(wdev);
err = 0;
if (wdev->sme_state != CFG80211_SME_IDLE) {
bool event = true;
if (wdev->wext.connect.ssid && len &&
len == wdev->wext.connect.ssid_len &&
memcmp(wdev->wext.connect.ssid, ssid, len) == 0)
goto out;
/* if SSID set now, we'll try to connect, avoid event */
if (len)
event = false;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, event);
if (err)
goto out;
}
wdev->wext.prev_bssid_valid = false;
wdev->wext.connect.ssid = wdev->wext.ssid;
memcpy(wdev->wext.ssid, ssid, len);
wdev->wext.connect.ssid_len = len;
wdev->wext.connect.crypto.control_port = false;
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
data->flags = 0;
wdev_lock(wdev);
if (wdev->current_bss) {
const u8 *ie = ieee80211_bss_get_ie(&wdev->current_bss->pub,
WLAN_EID_SSID);
if (ie) {
data->flags = 1;
data->length = ie[1];
memcpy(ssid, ie + 2, data->length);
}
} else if (wdev->wext.connect.ssid && wdev->wext.connect.ssid_len) {
data->flags = 1;
data->length = wdev->wext.connect.ssid_len;
memcpy(ssid, wdev->wext.connect.ssid, data->length);
}
wdev_unlock(wdev);
return 0;
}
int cfg80211_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
return -EINVAL;
if (ap_addr->sa_family != ARPHRD_ETHER)
return -EINVAL;
/* automatic mode */
if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
bssid = NULL;
cfg80211_lock_rdev(rdev);
mutex_lock(&rdev->devlist_mtx);
wdev_lock(wdev);
if (wdev->sme_state != CFG80211_SME_IDLE) {
err = 0;
/* both automatic */
if (!bssid && !wdev->wext.connect.bssid)
goto out;
/* fixed already - and no change */
if (wdev->wext.connect.bssid && bssid &&
compare_ether_addr(bssid, wdev->wext.connect.bssid) == 0)
goto out;
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, false);
if (err)
goto out;
}
if (bssid) {
memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
wdev->wext.connect.bssid = wdev->wext.bssid;
} else
wdev->wext.connect.bssid = NULL;
err = cfg80211_mgd_wext_connect(rdev, wdev);
out:
wdev_unlock(wdev);
mutex_unlock(&rdev->devlist_mtx);
cfg80211_unlock_rdev(rdev);
return err;
}
int cfg80211_mgd_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 station! */
if (WARN_ON(wdev->iftype != NL80211_IFTYPE_STATION))
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
memset(ap_addr->sa_data, 0, ETH_ALEN);
wdev_unlock(wdev);
return 0;
}
int cfg80211_wext_siwgenie(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
u8 *ie = extra;
int ie_len = data->length, err;
if (wdev->iftype != NL80211_IFTYPE_STATION)
return -EOPNOTSUPP;
if (!ie_len)
ie = NULL;
wdev_lock(wdev);
/* no change */
err = 0;
if (wdev->wext.ie_len == ie_len &&
memcmp(wdev->wext.ie, ie, ie_len) == 0)
goto out;
if (ie_len) {
ie = kmemdup(extra, ie_len, GFP_KERNEL);
if (!ie) {
err = -ENOMEM;
goto out;
}
} else
ie = NULL;
kfree(wdev->wext.ie);
wdev->wext.ie = ie;
wdev->wext.ie_len = ie_len;
if (wdev->sme_state != CFG80211_SME_IDLE) {
err = __cfg80211_disconnect(rdev, dev,
WLAN_REASON_DEAUTH_LEAVING, false);
if (err)
goto out;
}
/* userspace better not think we'll reconnect */
err = 0;
out:
wdev_unlock(wdev);
return err;
}
EXPORT_SYMBOL_GPL(cfg80211_wext_siwgenie);
int cfg80211_wext_siwmlme(struct net_device *dev,
struct iw_request_info *info,
struct iw_point *data, char *extra)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct iw_mlme *mlme = (struct iw_mlme *)extra;
struct cfg80211_registered_device *rdev;
int err;
if (!wdev)
return -EOPNOTSUPP;
rdev = wiphy_to_dev(wdev->wiphy);
if (wdev->iftype != NL80211_IFTYPE_STATION)
return -EINVAL;
if (mlme->addr.sa_family != ARPHRD_ETHER)
return -EINVAL;
wdev_lock(wdev);
switch (mlme->cmd) {
case IW_MLME_DEAUTH:
case IW_MLME_DISASSOC:
err = __cfg80211_disconnect(rdev, dev, mlme->reason_code,
true);
break;
default:
err = -EOPNOTSUPP;
break;
}
wdev_unlock(wdev);
return err;
}
EXPORT_SYMBOL_GPL(cfg80211_wext_siwmlme);