/* NetworkManager -- Network link manager * * Dan Williams * * 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 #include #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); }