kevin/linux
1
Fork 0
Code
8f7eb40749
linux/net/ieee80211/softmac/ieee80211softmac_auth.c
Joseph Jezak cb74c432e3 [PATCH] SoftMAC: Prevent multiple authentication attempts on the same network 
This patch addresses the "No queue exists" messages commonly seen during
authentication and associating.  These appear due to scheduling multiple
authentication attempts on the same network.  To prevent this, I added a
flag to stop multiple authentication attempts by the association layer.
I also added a check to the wx handler to see if we're connecting to a
different network than the one already in progress.  This scenario was
causing multiple requests on the same network because the network BSSID
was not being updated despite the fact that the ESSID changed.

Signed-off-by: Joseph Jezak <josejx@gentoo.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2006-07-05 13:42:58 -04:00

382 lines
11 KiB
C
Raw Blame History

/*
* This file contains the softmac's authentication logic.
*
* Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
* Joseph Jezak <josejx@gentoo.org>
* Larry Finger <Larry.Finger@lwfinger.net>
* Danny van Dyk <kugelfang@gentoo.org>
* Michael Buesch <mbuesch@freenet.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* The full GNU General Public License is included in this distribution in the
* file called COPYING.
*/
#include "ieee80211softmac_priv.h"
static void ieee80211softmac_auth_queue(void *data);
/* Queues an auth request to the desired AP */
int
ieee80211softmac_auth_req(struct ieee80211softmac_device *mac,
struct ieee80211softmac_network *net)
{
struct ieee80211softmac_auth_queue_item *auth;
unsigned long flags;
if (net->authenticating || net->authenticated)
return 0;
net->authenticating = 1;
/* Add the network if it's not already added */
ieee80211softmac_add_network(mac, net);
dprintk(KERN_NOTICE PFX "Queueing Authentication Request to "MAC_FMT"\n", MAC_ARG(net->bssid));
/* Queue the auth request */
auth = (struct ieee80211softmac_auth_queue_item *)
kmalloc(sizeof(struct ieee80211softmac_auth_queue_item), GFP_KERNEL);
if(auth == NULL)
return -ENOMEM;
auth->net = net;
auth->mac = mac;
auth->retry = IEEE80211SOFTMAC_AUTH_RETRY_LIMIT;
auth->state = IEEE80211SOFTMAC_AUTH_OPEN_REQUEST;
INIT_WORK(&auth->work, &ieee80211softmac_auth_queue, (void *)auth);
/* Lock (for list) */
spin_lock_irqsave(&mac->lock, flags);
/* add to list */
list_add_tail(&auth->list, &mac->auth_queue);
schedule_work(&auth->work);
spin_unlock_irqrestore(&mac->lock, flags);
return 0;
}
/* Sends an auth request to the desired AP and handles timeouts */
static void
ieee80211softmac_auth_queue(void *data)
{
struct ieee80211softmac_device *mac;
struct ieee80211softmac_auth_queue_item *auth;
struct ieee80211softmac_network *net;
unsigned long flags;
auth = (struct ieee80211softmac_auth_queue_item *)data;
net = auth->net;
mac = auth->mac;
if(auth->retry > 0) {
/* Switch to correct channel for this network */
mac->set_channel(mac->dev, net->channel);
/* Lock and set flags */
spin_lock_irqsave(&mac->lock, flags);
if (unlikely(!mac->running)) {
/* Prevent reschedule on workqueue flush */
spin_unlock_irqrestore(&mac->lock, flags);
return;
}
net->authenticated = 0;
/* add a timeout call so we eventually give up waiting for an auth reply */
schedule_delayed_work(&auth->work, IEEE80211SOFTMAC_AUTH_TIMEOUT);
auth->retry--;
spin_unlock_irqrestore(&mac->lock, flags);
if (ieee80211softmac_send_mgt_frame(mac, auth->net, IEEE80211_STYPE_AUTH, auth->state))
dprintk(KERN_NOTICE PFX "Sending Authentication Request to "MAC_FMT" failed (this shouldn't happen, wait for the timeout).\n", MAC_ARG(net->bssid));
else
dprintk(KERN_NOTICE PFX "Sent Authentication Request to "MAC_FMT".\n", MAC_ARG(net->bssid));
return;
}
printkl(KERN_WARNING PFX "Authentication timed out with "MAC_FMT"\n", MAC_ARG(net->bssid));
/* Remove this item from the queue */
spin_lock_irqsave(&mac->lock, flags);
net->authenticating = 0;
ieee80211softmac_call_events_locked(mac, IEEE80211SOFTMAC_EVENT_AUTH_TIMEOUT, net);
cancel_delayed_work(&auth->work); /* just to make sure... */
list_del(&auth->list);
spin_unlock_irqrestore(&mac->lock, flags);
/* Free it */
kfree(auth);
}
/* Handle the auth response from the AP
* This should be registered with ieee80211 as handle_auth
*/
int
ieee80211softmac_auth_resp(struct net_device *dev, struct ieee80211_auth *auth)
{
struct list_head *list_ptr;
struct ieee80211softmac_device *mac = ieee80211_priv(dev);
struct ieee80211softmac_auth_queue_item *aq = NULL;
struct ieee80211softmac_network *net = NULL;
unsigned long flags;
u8 * data;
if (unlikely(!mac->running))
return -ENODEV;
/* Find correct auth queue item */
spin_lock_irqsave(&mac->lock, flags);
list_for_each(list_ptr, &mac->auth_queue) {
aq = list_entry(list_ptr, struct ieee80211softmac_auth_queue_item, list);
net = aq->net;
if (!memcmp(net->bssid, auth->header.addr2, ETH_ALEN))
break;
else
aq = NULL;
}
spin_unlock_irqrestore(&mac->lock, flags);
/* Make sure that we've got an auth queue item for this request */
if(aq == NULL)
{
printkl(KERN_DEBUG PFX "Authentication response received from "MAC_FMT" but no queue item exists.\n", MAC_ARG(auth->header.addr2));
/* Error #? */
return -1;
}
/* Check for out of order authentication */
if(!net->authenticating)
{
printkl(KERN_DEBUG PFX "Authentication response received from "MAC_FMT" but did not request authentication.\n",MAC_ARG(auth->header.addr2));
return -1;
}
/* Parse the auth packet */
switch(auth->algorithm) {
case WLAN_AUTH_OPEN:
/* Check the status code of the response */
switch(auth->status) {
case WLAN_STATUS_SUCCESS:
/* Update the status to Authenticated */
spin_lock_irqsave(&mac->lock, flags);
net->authenticating = 0;
net->authenticated = 1;
spin_unlock_irqrestore(&mac->lock, flags);
/* Send event */
printkl(KERN_NOTICE PFX "Open Authentication completed with "MAC_FMT"\n", MAC_ARG(net->bssid));
ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_AUTHENTICATED, net);
break;
default:
/* Lock and reset flags */
spin_lock_irqsave(&mac->lock, flags);
net->authenticated = 0;
net->authenticating = 0;
spin_unlock_irqrestore(&mac->lock, flags);
printkl(KERN_NOTICE PFX "Open Authentication with "MAC_FMT" failed, error code: %i\n",
MAC_ARG(net->bssid), le16_to_cpup(&auth->status));
/* Count the error? */
break;
}
goto free_aq;
break;
case WLAN_AUTH_SHARED_KEY:
/* Figure out where we are in the process */
switch(auth->transaction) {
case IEEE80211SOFTMAC_AUTH_SHARED_CHALLENGE:
/* Check to make sure we have a challenge IE */
data = (u8 *)auth->info_element;
if(*data++ != MFIE_TYPE_CHALLENGE){
printkl(KERN_NOTICE PFX "Shared Key Authentication failed due to a missing challenge.\n");
break;
}
/* Save the challenge */
spin_lock_irqsave(&mac->lock, flags);
net->challenge_len = *data++;
if(net->challenge_len > WLAN_AUTH_CHALLENGE_LEN)
net->challenge_len = WLAN_AUTH_CHALLENGE_LEN;
if(net->challenge != NULL)
kfree(net->challenge);
net->challenge = kmalloc(net->challenge_len, GFP_ATOMIC);
memcpy(net->challenge, data, net->challenge_len);
aq->state = IEEE80211SOFTMAC_AUTH_SHARED_RESPONSE;
spin_unlock_irqrestore(&mac->lock, flags);
/* Send our response */
ieee80211softmac_send_mgt_frame(mac, aq->net, IEEE80211_STYPE_AUTH, aq->state);
return 0;
case IEEE80211SOFTMAC_AUTH_SHARED_PASS:
kfree(net->challenge);
net->challenge = NULL;
net->challenge_len = 0;
/* Check the status code of the response */
switch(auth->status) {
case WLAN_STATUS_SUCCESS:
/* Update the status to Authenticated */
spin_lock_irqsave(&mac->lock, flags);
net->authenticating = 0;
net->authenticated = 1;
spin_unlock_irqrestore(&mac->lock, flags);
printkl(KERN_NOTICE PFX "Shared Key Authentication completed with "MAC_FMT"\n",
MAC_ARG(net->bssid));
ieee80211softmac_call_events(mac, IEEE80211SOFTMAC_EVENT_AUTHENTICATED, net);
break;
default:
printkl(KERN_NOTICE PFX "Shared Key Authentication with "MAC_FMT" failed, error code: %i\n",
MAC_ARG(net->bssid), le16_to_cpup(&auth->status));
/* Lock and reset flags */
spin_lock_irqsave(&mac->lock, flags);
net->authenticating = 0;
net->authenticated = 0;
spin_unlock_irqrestore(&mac->lock, flags);
/* Count the error? */
break;
}
goto free_aq;
break;
default:
printkl(KERN_WARNING PFX "Unhandled Authentication Step: %i\n", auth->transaction);
break;
}
goto free_aq;
break;
default:
/* ERROR */
goto free_aq;
break;
}
return 0;
free_aq:
/* Cancel the timeout */
spin_lock_irqsave(&mac->lock, flags);
cancel_delayed_work(&aq->work);
/* Remove this item from the queue */
list_del(&aq->list);
spin_unlock_irqrestore(&mac->lock, flags);
/* Free it */
kfree(aq);
return 0;
}
/*
* Handle deauthorization
*/
static void
ieee80211softmac_deauth_from_net(struct ieee80211softmac_device *mac,
struct ieee80211softmac_network *net)
{
struct ieee80211softmac_auth_queue_item *aq = NULL;
struct list_head *list_ptr;
unsigned long flags;
/* deauthentication implies disassociation */
ieee80211softmac_disassoc(mac);
/* Lock and reset status flags */
spin_lock_irqsave(&mac->lock, flags);
net->authenticating = 0;
net->authenticated = 0;
/* Find correct auth queue item, if it exists */
list_for_each(list_ptr, &mac->auth_queue) {
aq = list_entry(list_ptr, struct ieee80211softmac_auth_queue_item, list);
if (!memcmp(net->bssid, aq->net->bssid, ETH_ALEN))
break;
else
aq = NULL;
}
/* Cancel pending work */
if(aq != NULL)
/* Not entirely safe? What about running work? */
cancel_delayed_work(&aq->work);
/* Free our network ref */
ieee80211softmac_del_network_locked(mac, net);
if(net->challenge != NULL)
kfree(net->challenge);
kfree(net);
/* can't transmit data right now... */
netif_carrier_off(mac->dev);
spin_unlock_irqrestore(&mac->lock, flags);
}
/*
* Sends a deauth request to the desired AP
*/
int
ieee80211softmac_deauth_req(struct ieee80211softmac_device *mac,
struct ieee80211softmac_network *net, int reason)
{
int ret;
/* Make sure the network is authenticated */
if (!net->authenticated)
{
printkl(KERN_DEBUG PFX "Can't send deauthentication packet, network is not authenticated.\n");
/* Error okay? */
return -EPERM;
}
/* Send the de-auth packet */
if((ret = ieee80211softmac_send_mgt_frame(mac, net, IEEE80211_STYPE_DEAUTH, reason)))
return ret;
ieee80211softmac_deauth_from_net(mac, net);
return 0;
}
/*
* This should be registered with ieee80211 as handle_deauth
*/
int
ieee80211softmac_deauth_resp(struct net_device *dev, struct ieee80211_deauth *deauth)
{
struct ieee80211softmac_network *net = NULL;
struct ieee80211softmac_device *mac = ieee80211_priv(dev);
if (unlikely(!mac->running))
return -ENODEV;
if (!deauth) {
dprintk("deauth without deauth packet. eek!\n");
return 0;
}
net = ieee80211softmac_get_network_by_bssid(mac, deauth->header.addr2);
if (net == NULL) {
printkl(KERN_DEBUG PFX "Received deauthentication packet from "MAC_FMT", but that network is unknown.\n",
MAC_ARG(deauth->header.addr2));
return 0;
}
/* Make sure the network is authenticated */
if(!net->authenticated)
{
printkl(KERN_DEBUG PFX "Can't perform deauthentication, network is not authenticated.\n");
/* Error okay? */
return -EPERM;
}
ieee80211softmac_deauth_from_net(mac, net);
/* let's try to re-associate */
schedule_work(&mac->associnfo.work);
return 0;
}
View Git Blame Copy Permalink