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/* NetworkManager -- Network link manager
*
* Dan Williams <dcbw@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* (C) Copyright 2004 Red Hat, Inc.
*/
#include <stdio.h>
#include <iwlib.h>
#include "NetworkManager.h"
#include "NetworkManagerDevice.h"
#include "NetworkManagerWireless.h"
#include "NetworkManagerPolicy.h"
#include "NetworkManagerUtils.h"
extern gboolean debug;
/*
* nm_wireless_is_most_prefered_ap
*
* For a given AP, filter it through the allowed list and return TRUE if its
* both allowed _and_ has a better priority than highest_priority.
*
*/
static gboolean nm_wireless_is_most_prefered_ap (NMAccessPoint *ap, int *highest_priority)
{
NMData *data = nm_get_global_data ();
GSList *element;
gboolean is_most_preferred = FALSE;
g_return_val_if_fail (ap != NULL, FALSE);
/* Attempt to acquire mutex for device list iteration.
* If the acquire fails, just ignore the scan completely.
*/
if (nm_try_acquire_mutex (data->allowed_ap_list_mutex, __FUNCTION__))
{
element = data->allowed_ap_list;
while (element)
{
NMAccessPoint *allowed_ap = (NMAccessPoint *)(element->data);
/* If the essid of the scanned ap matches one in our allowed list, and this AP is
* a higher priority than one we may possibly have already found.
*/
if ( allowed_ap
&& (nm_null_safe_strcmp (nm_ap_get_essid (allowed_ap), nm_ap_get_essid (ap)) == 0)
&& (nm_ap_get_priority (allowed_ap) < *highest_priority))
{
is_most_preferred = TRUE;
break;
}
element = g_slist_next (element);
}
nm_unlock_mutex (data->allowed_ap_list_mutex, __FUNCTION__);
}
else
NM_DEBUG_PRINT( "nm_wireless_is_most_prefered_ap() could not acquire allowed access point mutex.\n" );
return (is_most_preferred);
}
/*
* nm_wireless_do_scan
*
* Runs the actual scan fore access points.
*
*/
void nm_wireless_do_scan (NMData *data, NMDevice *dev)
{
int iwlib_socket;
g_return_if_fail (data != NULL);
g_return_if_fail (dev != NULL);
if (nm_device_get_iface_type (dev) != NM_IFACE_TYPE_WIRELESS_ETHERNET)
return;
if (nm_device_get_supports_wireless_scan (dev) == FALSE)
return;
/* Device must be up before we can scan */
if (!nm_device_is_up (dev))
nm_device_bring_up (dev);
iwlib_socket = iw_sockets_open ();
if (iwlib_socket >= 0)
{
wireless_scan_head scan_results = { NULL, 0 };
wireless_scan *tmp_ap;
int err;
NMAccessPoint *highest_priority_ap = NULL;
int highest_priority = NM_AP_PRIORITY_WORST;
/* Clear out the device's ap list */
nm_device_ap_list_clear (dev);
err = iw_scan (iwlib_socket, nm_device_get_iface (dev), WIRELESS_EXT, &scan_results);
/* Iterate over scan results and pick a "most" preferred access point. */
tmp_ap = scan_results.result;
while (tmp_ap)
{
/* Blank essids usually indicate an AP that is not broadcasting its essid,
* but since its not broadcasting the essid, we cannot use that ap yet.
*/
if (tmp_ap->b.has_essid && tmp_ap->b.essid_on && (strlen (tmp_ap->b.essid) > 0))
{
NMAccessPoint *nm_ap = nm_ap_new ();
/* Copy over info from scan to local structure */
nm_ap_set_essid (nm_ap, tmp_ap->b.essid);
if (tmp_ap->has_ap_addr)
{
char buf[20];
memset (&buf[0], 0, 20);
iw_ether_ntop((const struct ether_addr *) (tmp_ap->ap_addr.sa_data), &buf[0]);
nm_ap_set_address (nm_ap, buf);
}
nm_ap_set_quality (nm_ap, tmp_ap->stats.qual.qual);
if (tmp_ap->b.has_freq)
nm_ap_set_freq (nm_ap, tmp_ap->b.freq);
/* Add the AP to the device's AP list, no matter if its allowed or not */
nm_device_ap_list_add (dev, nm_ap);
if (nm_wireless_is_most_prefered_ap (nm_ap, &highest_priority))
{
if (highest_priority_ap)
nm_ap_unref (highest_priority_ap);
highest_priority_ap = nm_ap_new_from_ap (nm_ap);
}
nm_ap_unref (nm_ap);
}
tmp_ap = tmp_ap->next;
}
nm_dispose_scan_results (scan_results.result);
/* If we have the "most" preferred access point, and its different than the current
* access point, switch to it during the next cycle.
*/
if ( highest_priority_ap
&& (!data->desired_ap || (nm_null_safe_strcmp (nm_device_get_essid (dev), nm_ap_get_essid (highest_priority_ap)) != 0)))
{
if (data->desired_ap)
nm_ap_unref (data->desired_ap);
data->desired_ap = nm_ap_new_from_ap (highest_priority_ap);
data->state_modified = TRUE;
nm_ap_unref (highest_priority_ap);
}
close (iwlib_socket);
}
else
NM_DEBUG_PRINT ("nm_wireless_do_scan() could not get a control socket for the wireless card.\n" );
}
/*
* nm_wireless_scan_monitor
*
* Called every 10s to get a list of access points.
*
*/
gboolean nm_wireless_scan_monitor (gpointer user_data)
{
NMData *data = (NMData *)user_data;
GSList *element;
NMDevice *dev;
g_return_val_if_fail (data != NULL, TRUE);
if (!data->active_device)
return (TRUE);
/* Grab a current list of allowed access points */
nm_policy_update_allowed_access_points (data);
/* Attempt to acquire mutex for device list iteration.
* If the acquire fails, just ignore the scan completely.
*/
if (nm_try_acquire_mutex (data->dev_list_mutex, __FUNCTION__))
{
if (data->active_device && (nm_device_get_iface_type (data->active_device) == NM_IFACE_TYPE_WIRELESS_ETHERNET))
nm_wireless_do_scan (data, data->active_device);
nm_unlock_mutex (data->dev_list_mutex, __FUNCTION__);
}
else
NM_DEBUG_PRINT( "nm_wireless_scan_monitor() could not acquire device list mutex.\n" );
return (TRUE);
}
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