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linux/net/wireless/mlme.c
Johannes Berg a58ce43f2f mac80211: avoid spurious deauth frames/messages
With WEXT, it happens frequently that the SME
requests an authentication but then deauthenticates
right away because some new parameters came along.
Every time this happens we print a deauth message
and send a deauth frame, but both of that is rather
confusing. Avoid it by aborting the authentication
process silently, and telling cfg80211 about that.

The patch looks larger than it really is:
__cfg80211_auth_remove() is split out from
cfg80211_send_auth_timeout(), there's no new code
except __cfg80211_auth_canceled() (a one-liner) and
the mac80211 bits (7 new lines of code).

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-19 11:09:02 -05:00

676 lines
18 KiB
C

/*
* cfg80211 MLME SAP interface
*
* Copyright (c) 2009, Jouni Malinen <j@w1.fi>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/nl80211.h>
#include <linux/wireless.h>
#include <net/cfg80211.h>
#include <net/iw_handler.h>
#include "core.h"
#include "nl80211.h"
void cfg80211_send_rx_auth(struct net_device *dev, const u8 *buf, size_t len)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)buf;
u8 *bssid = mgmt->bssid;
int i;
u16 status = le16_to_cpu(mgmt->u.auth.status_code);
bool done = false;
wdev_lock(wdev);
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->authtry_bsses[i] &&
memcmp(wdev->authtry_bsses[i]->pub.bssid, bssid,
ETH_ALEN) == 0) {
if (status == WLAN_STATUS_SUCCESS) {
wdev->auth_bsses[i] = wdev->authtry_bsses[i];
} else {
cfg80211_unhold_bss(wdev->authtry_bsses[i]);
cfg80211_put_bss(&wdev->authtry_bsses[i]->pub);
}
wdev->authtry_bsses[i] = NULL;
done = true;
break;
}
}
WARN_ON(!done);
nl80211_send_rx_auth(rdev, dev, buf, len, GFP_KERNEL);
cfg80211_sme_rx_auth(dev, buf, len);
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_rx_auth);
void cfg80211_send_rx_assoc(struct net_device *dev, const u8 *buf, size_t len)
{
u16 status_code;
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)buf;
u8 *ie = mgmt->u.assoc_resp.variable;
int i, ieoffs = offsetof(struct ieee80211_mgmt, u.assoc_resp.variable);
struct cfg80211_internal_bss *bss = NULL;
wdev_lock(wdev);
status_code = le16_to_cpu(mgmt->u.assoc_resp.status_code);
/*
* This is a bit of a hack, we don't notify userspace of
* a (re-)association reply if we tried to send a reassoc
* and got a reject -- we only try again with an assoc
* frame instead of reassoc.
*/
if (status_code != WLAN_STATUS_SUCCESS && wdev->conn &&
cfg80211_sme_failed_reassoc(wdev))
goto out;
nl80211_send_rx_assoc(rdev, dev, buf, len, GFP_KERNEL);
if (status_code == WLAN_STATUS_SUCCESS) {
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (!wdev->auth_bsses[i])
continue;
if (memcmp(wdev->auth_bsses[i]->pub.bssid, mgmt->bssid,
ETH_ALEN) == 0) {
bss = wdev->auth_bsses[i];
wdev->auth_bsses[i] = NULL;
/* additional reference to drop hold */
cfg80211_ref_bss(bss);
break;
}
}
WARN_ON(!bss);
} else if (wdev->conn) {
cfg80211_sme_failed_assoc(wdev);
/*
* do not call connect_result() now because the
* sme will schedule work that does it later.
*/
goto out;
}
if (!wdev->conn && wdev->sme_state == CFG80211_SME_IDLE) {
/*
* This is for the userspace SME, the CONNECTING
* state will be changed to CONNECTED by
* __cfg80211_connect_result() below.
*/
wdev->sme_state = CFG80211_SME_CONNECTING;
}
/* this consumes one bss reference (unless bss is NULL) */
__cfg80211_connect_result(dev, mgmt->bssid, NULL, 0, ie, len - ieoffs,
status_code,
status_code == WLAN_STATUS_SUCCESS,
bss ? &bss->pub : NULL);
/* drop hold now, and also reference acquired above */
if (bss) {
cfg80211_unhold_bss(bss);
cfg80211_put_bss(&bss->pub);
}
out:
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_rx_assoc);
void __cfg80211_send_deauth(struct net_device *dev,
const u8 *buf, size_t len)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)buf;
const u8 *bssid = mgmt->bssid;
int i;
ASSERT_WDEV_LOCK(wdev);
nl80211_send_deauth(rdev, dev, buf, len, GFP_KERNEL);
if (wdev->current_bss &&
memcmp(wdev->current_bss->pub.bssid, bssid, ETH_ALEN) == 0) {
cfg80211_unhold_bss(wdev->current_bss);
cfg80211_put_bss(&wdev->current_bss->pub);
wdev->current_bss = NULL;
} else for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->auth_bsses[i] &&
memcmp(wdev->auth_bsses[i]->pub.bssid, bssid, ETH_ALEN) == 0) {
cfg80211_unhold_bss(wdev->auth_bsses[i]);
cfg80211_put_bss(&wdev->auth_bsses[i]->pub);
wdev->auth_bsses[i] = NULL;
break;
}
if (wdev->authtry_bsses[i] &&
memcmp(wdev->authtry_bsses[i]->pub.bssid, bssid, ETH_ALEN) == 0) {
cfg80211_unhold_bss(wdev->authtry_bsses[i]);
cfg80211_put_bss(&wdev->authtry_bsses[i]->pub);
wdev->authtry_bsses[i] = NULL;
break;
}
}
if (wdev->sme_state == CFG80211_SME_CONNECTED) {
u16 reason_code;
bool from_ap;
reason_code = le16_to_cpu(mgmt->u.deauth.reason_code);
from_ap = memcmp(mgmt->sa, dev->dev_addr, ETH_ALEN) != 0;
__cfg80211_disconnected(dev, NULL, 0, reason_code, from_ap);
} else if (wdev->sme_state == CFG80211_SME_CONNECTING) {
__cfg80211_connect_result(dev, mgmt->bssid, NULL, 0, NULL, 0,
WLAN_STATUS_UNSPECIFIED_FAILURE,
false, NULL);
}
}
EXPORT_SYMBOL(__cfg80211_send_deauth);
void cfg80211_send_deauth(struct net_device *dev, const u8 *buf, size_t len)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
wdev_lock(wdev);
__cfg80211_send_deauth(dev, buf, len);
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_deauth);
void __cfg80211_send_disassoc(struct net_device *dev,
const u8 *buf, size_t len)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *)buf;
const u8 *bssid = mgmt->bssid;
int i;
u16 reason_code;
bool from_ap;
bool done = false;
ASSERT_WDEV_LOCK(wdev);
nl80211_send_disassoc(rdev, dev, buf, len, GFP_KERNEL);
if (wdev->sme_state != CFG80211_SME_CONNECTED)
return;
if (wdev->current_bss &&
memcmp(wdev->current_bss->pub.bssid, bssid, ETH_ALEN) == 0) {
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->authtry_bsses[i] || wdev->auth_bsses[i])
continue;
wdev->auth_bsses[i] = wdev->current_bss;
wdev->current_bss = NULL;
done = true;
cfg80211_sme_disassoc(dev, i);
break;
}
WARN_ON(!done);
} else
WARN_ON(1);
reason_code = le16_to_cpu(mgmt->u.disassoc.reason_code);
from_ap = memcmp(mgmt->sa, dev->dev_addr, ETH_ALEN) != 0;
__cfg80211_disconnected(dev, NULL, 0, reason_code, from_ap);
}
EXPORT_SYMBOL(__cfg80211_send_disassoc);
void cfg80211_send_disassoc(struct net_device *dev, const u8 *buf, size_t len)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
wdev_lock(wdev);
__cfg80211_send_disassoc(dev, buf, len);
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_disassoc);
static void __cfg80211_auth_remove(struct wireless_dev *wdev, const u8 *addr)
{
int i;
bool done = false;
ASSERT_WDEV_LOCK(wdev);
for (i = 0; addr && i < MAX_AUTH_BSSES; i++) {
if (wdev->authtry_bsses[i] &&
memcmp(wdev->authtry_bsses[i]->pub.bssid,
addr, ETH_ALEN) == 0) {
cfg80211_unhold_bss(wdev->authtry_bsses[i]);
cfg80211_put_bss(&wdev->authtry_bsses[i]->pub);
wdev->authtry_bsses[i] = NULL;
done = true;
break;
}
}
WARN_ON(!done);
}
void __cfg80211_auth_canceled(struct net_device *dev, const u8 *addr)
{
__cfg80211_auth_remove(dev->ieee80211_ptr, addr);
}
EXPORT_SYMBOL(__cfg80211_auth_canceled);
void cfg80211_send_auth_timeout(struct net_device *dev, const u8 *addr)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
wdev_lock(wdev);
nl80211_send_auth_timeout(rdev, dev, addr, GFP_KERNEL);
if (wdev->sme_state == CFG80211_SME_CONNECTING)
__cfg80211_connect_result(dev, addr, NULL, 0, NULL, 0,
WLAN_STATUS_UNSPECIFIED_FAILURE,
false, NULL);
__cfg80211_auth_remove(wdev, addr);
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_auth_timeout);
void cfg80211_send_assoc_timeout(struct net_device *dev, const u8 *addr)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct wiphy *wiphy = wdev->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
int i;
bool done = false;
wdev_lock(wdev);
nl80211_send_assoc_timeout(rdev, dev, addr, GFP_KERNEL);
if (wdev->sme_state == CFG80211_SME_CONNECTING)
__cfg80211_connect_result(dev, addr, NULL, 0, NULL, 0,
WLAN_STATUS_UNSPECIFIED_FAILURE,
false, NULL);
for (i = 0; addr && i < MAX_AUTH_BSSES; i++) {
if (wdev->auth_bsses[i] &&
memcmp(wdev->auth_bsses[i]->pub.bssid,
addr, ETH_ALEN) == 0) {
cfg80211_unhold_bss(wdev->auth_bsses[i]);
cfg80211_put_bss(&wdev->auth_bsses[i]->pub);
wdev->auth_bsses[i] = NULL;
done = true;
break;
}
}
WARN_ON(!done);
wdev_unlock(wdev);
}
EXPORT_SYMBOL(cfg80211_send_assoc_timeout);
void cfg80211_michael_mic_failure(struct net_device *dev, const u8 *addr,
enum nl80211_key_type key_type, int key_id,
const u8 *tsc, gfp_t gfp)
{
struct wiphy *wiphy = dev->ieee80211_ptr->wiphy;
struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
#ifdef CONFIG_CFG80211_WEXT
union iwreq_data wrqu;
char *buf = kmalloc(128, gfp);
if (buf) {
sprintf(buf, "MLME-MICHAELMICFAILURE.indication("
"keyid=%d %scast addr=%pM)", key_id,
key_type == NL80211_KEYTYPE_GROUP ? "broad" : "uni",
addr);
memset(&wrqu, 0, sizeof(wrqu));
wrqu.data.length = strlen(buf);
wireless_send_event(dev, IWEVCUSTOM, &wrqu, buf);
kfree(buf);
}
#endif
nl80211_michael_mic_failure(rdev, dev, addr, key_type, key_id, tsc, gfp);
}
EXPORT_SYMBOL(cfg80211_michael_mic_failure);
/* some MLME handling for userspace SME */
int __cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
struct net_device *dev,
struct ieee80211_channel *chan,
enum nl80211_auth_type auth_type,
const u8 *bssid,
const u8 *ssid, int ssid_len,
const u8 *ie, int ie_len,
const u8 *key, int key_len, int key_idx)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_auth_request req;
struct cfg80211_internal_bss *bss;
int i, err, slot = -1, nfree = 0;
ASSERT_WDEV_LOCK(wdev);
if (auth_type == NL80211_AUTHTYPE_SHARED_KEY)
if (!key || !key_len || key_idx < 0 || key_idx > 4)
return -EINVAL;
if (wdev->current_bss &&
memcmp(bssid, wdev->current_bss->pub.bssid, ETH_ALEN) == 0)
return -EALREADY;
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->authtry_bsses[i] &&
memcmp(bssid, wdev->authtry_bsses[i]->pub.bssid,
ETH_ALEN) == 0)
return -EALREADY;
if (wdev->auth_bsses[i] &&
memcmp(bssid, wdev->auth_bsses[i]->pub.bssid,
ETH_ALEN) == 0)
return -EALREADY;
}
memset(&req, 0, sizeof(req));
req.ie = ie;
req.ie_len = ie_len;
req.auth_type = auth_type;
req.bss = cfg80211_get_bss(&rdev->wiphy, chan, bssid, ssid, ssid_len,
WLAN_CAPABILITY_ESS, WLAN_CAPABILITY_ESS);
req.key = key;
req.key_len = key_len;
req.key_idx = key_idx;
if (!req.bss)
return -ENOENT;
bss = bss_from_pub(req.bss);
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (!wdev->auth_bsses[i] && !wdev->authtry_bsses[i]) {
slot = i;
nfree++;
}
}
/* we need one free slot for disassoc and one for this auth */
if (nfree < 2) {
err = -ENOSPC;
goto out;
}
wdev->authtry_bsses[slot] = bss;
cfg80211_hold_bss(bss);
err = rdev->ops->auth(&rdev->wiphy, dev, &req);
if (err) {
wdev->authtry_bsses[slot] = NULL;
cfg80211_unhold_bss(bss);
}
out:
if (err)
cfg80211_put_bss(req.bss);
return err;
}
int cfg80211_mlme_auth(struct cfg80211_registered_device *rdev,
struct net_device *dev, struct ieee80211_channel *chan,
enum nl80211_auth_type auth_type, const u8 *bssid,
const u8 *ssid, int ssid_len,
const u8 *ie, int ie_len,
const u8 *key, int key_len, int key_idx)
{
int err;
wdev_lock(dev->ieee80211_ptr);
err = __cfg80211_mlme_auth(rdev, dev, chan, auth_type, bssid,
ssid, ssid_len, ie, ie_len,
key, key_len, key_idx);
wdev_unlock(dev->ieee80211_ptr);
return err;
}
int __cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
struct net_device *dev,
struct ieee80211_channel *chan,
const u8 *bssid, const u8 *prev_bssid,
const u8 *ssid, int ssid_len,
const u8 *ie, int ie_len, bool use_mfp,
struct cfg80211_crypto_settings *crypt)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_assoc_request req;
struct cfg80211_internal_bss *bss;
int i, err, slot = -1;
bool was_connected = false;
ASSERT_WDEV_LOCK(wdev);
memset(&req, 0, sizeof(req));
if (wdev->current_bss && prev_bssid &&
memcmp(wdev->current_bss->pub.bssid, prev_bssid, ETH_ALEN) == 0) {
/*
* Trying to reassociate: Allow this to proceed and let the old
* association to be dropped when the new one is completed.
*/
if (wdev->sme_state == CFG80211_SME_CONNECTED) {
was_connected = true;
wdev->sme_state = CFG80211_SME_CONNECTING;
}
} else if (wdev->current_bss)
return -EALREADY;
req.ie = ie;
req.ie_len = ie_len;
memcpy(&req.crypto, crypt, sizeof(req.crypto));
req.use_mfp = use_mfp;
req.prev_bssid = prev_bssid;
req.bss = cfg80211_get_bss(&rdev->wiphy, chan, bssid, ssid, ssid_len,
WLAN_CAPABILITY_ESS, WLAN_CAPABILITY_ESS);
if (!req.bss) {
if (was_connected)
wdev->sme_state = CFG80211_SME_CONNECTED;
return -ENOENT;
}
bss = bss_from_pub(req.bss);
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (bss == wdev->auth_bsses[i]) {
slot = i;
break;
}
}
if (slot < 0) {
err = -ENOTCONN;
goto out;
}
err = rdev->ops->assoc(&rdev->wiphy, dev, &req);
out:
if (err && was_connected)
wdev->sme_state = CFG80211_SME_CONNECTED;
/* still a reference in wdev->auth_bsses[slot] */
cfg80211_put_bss(req.bss);
return err;
}
int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
struct net_device *dev,
struct ieee80211_channel *chan,
const u8 *bssid, const u8 *prev_bssid,
const u8 *ssid, int ssid_len,
const u8 *ie, int ie_len, bool use_mfp,
struct cfg80211_crypto_settings *crypt)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
wdev_lock(wdev);
err = __cfg80211_mlme_assoc(rdev, dev, chan, bssid, prev_bssid,
ssid, ssid_len, ie, ie_len, use_mfp, crypt);
wdev_unlock(wdev);
return err;
}
int __cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
struct net_device *dev, const u8 *bssid,
const u8 *ie, int ie_len, u16 reason)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_deauth_request req;
int i;
ASSERT_WDEV_LOCK(wdev);
memset(&req, 0, sizeof(req));
req.reason_code = reason;
req.ie = ie;
req.ie_len = ie_len;
if (wdev->current_bss &&
memcmp(wdev->current_bss->pub.bssid, bssid, ETH_ALEN) == 0) {
req.bss = &wdev->current_bss->pub;
} else for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->auth_bsses[i] &&
memcmp(bssid, wdev->auth_bsses[i]->pub.bssid, ETH_ALEN) == 0) {
req.bss = &wdev->auth_bsses[i]->pub;
break;
}
if (wdev->authtry_bsses[i] &&
memcmp(bssid, wdev->authtry_bsses[i]->pub.bssid, ETH_ALEN) == 0) {
req.bss = &wdev->authtry_bsses[i]->pub;
break;
}
}
if (!req.bss)
return -ENOTCONN;
return rdev->ops->deauth(&rdev->wiphy, dev, &req, wdev);
}
int cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
struct net_device *dev, const u8 *bssid,
const u8 *ie, int ie_len, u16 reason)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
wdev_lock(wdev);
err = __cfg80211_mlme_deauth(rdev, dev, bssid, ie, ie_len, reason);
wdev_unlock(wdev);
return err;
}
static int __cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
struct net_device *dev, const u8 *bssid,
const u8 *ie, int ie_len, u16 reason)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_disassoc_request req;
ASSERT_WDEV_LOCK(wdev);
if (wdev->sme_state != CFG80211_SME_CONNECTED)
return -ENOTCONN;
if (WARN_ON(!wdev->current_bss))
return -ENOTCONN;
memset(&req, 0, sizeof(req));
req.reason_code = reason;
req.ie = ie;
req.ie_len = ie_len;
if (memcmp(wdev->current_bss->pub.bssid, bssid, ETH_ALEN) == 0)
req.bss = &wdev->current_bss->pub;
else
return -ENOTCONN;
return rdev->ops->disassoc(&rdev->wiphy, dev, &req, wdev);
}
int cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
struct net_device *dev, const u8 *bssid,
const u8 *ie, int ie_len, u16 reason)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
int err;
wdev_lock(wdev);
err = __cfg80211_mlme_disassoc(rdev, dev, bssid, ie, ie_len, reason);
wdev_unlock(wdev);
return err;
}
void cfg80211_mlme_down(struct cfg80211_registered_device *rdev,
struct net_device *dev)
{
struct wireless_dev *wdev = dev->ieee80211_ptr;
struct cfg80211_deauth_request req;
int i;
ASSERT_WDEV_LOCK(wdev);
if (!rdev->ops->deauth)
return;
memset(&req, 0, sizeof(req));
req.reason_code = WLAN_REASON_DEAUTH_LEAVING;
req.ie = NULL;
req.ie_len = 0;
if (wdev->current_bss) {
req.bss = &wdev->current_bss->pub;
rdev->ops->deauth(&rdev->wiphy, dev, &req, wdev);
if (wdev->current_bss) {
cfg80211_unhold_bss(wdev->current_bss);
cfg80211_put_bss(&wdev->current_bss->pub);
wdev->current_bss = NULL;
}
}
for (i = 0; i < MAX_AUTH_BSSES; i++) {
if (wdev->auth_bsses[i]) {
req.bss = &wdev->auth_bsses[i]->pub;
rdev->ops->deauth(&rdev->wiphy, dev, &req, wdev);
if (wdev->auth_bsses[i]) {
cfg80211_unhold_bss(wdev->auth_bsses[i]);
cfg80211_put_bss(&wdev->auth_bsses[i]->pub);
wdev->auth_bsses[i] = NULL;
}
}
if (wdev->authtry_bsses[i]) {
req.bss = &wdev->authtry_bsses[i]->pub;
rdev->ops->deauth(&rdev->wiphy, dev, &req, wdev);
if (wdev->authtry_bsses[i]) {
cfg80211_unhold_bss(wdev->authtry_bsses[i]);
cfg80211_put_bss(&wdev->authtry_bsses[i]->pub);
wdev->authtry_bsses[i] = NULL;
}
}
}
}