hostapd/wpa_supplicant/blacklist.c
Jouni Malinen 7e6646c794 SME: Fix re-try after auth/assoc timeout/failure
There were various issues in how the SME (i.e., nl80211-based driver
interface) handled various authentication and association timeouts and
failures. Authentication failure was not handled at all (wpa_supplicant
just stopped trying to connect completely), authentication timeout
resulted in blacklisting not working in the expected way (i.e., the same
BSS could be selected continuously), and association cases had similar
problems.

Use a common function to handle all these cases and fix the blacklist
operation. Use smaller delay before trying to scan again during the
initial cycle through the available APs to speed up connection. Add
a special case for another-BSS-in-the-same-ESS being present to
speed up recovery from networks with multiple APs doing load balancing
in various odd ways that are deployed out there.
2010-11-25 22:00:04 +02:00

133 lines
3.3 KiB
C

/*
* wpa_supplicant - Temporary BSSID blacklist
* Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#include "wpa_supplicant_i.h"
#include "blacklist.h"
/**
* wpa_blacklist_get - Get the blacklist entry for a BSSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* Returns: Matching blacklist entry for the BSSID or %NULL if not found
*/
struct wpa_blacklist * wpa_blacklist_get(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_blacklist *e;
e = wpa_s->blacklist;
while (e) {
if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0)
return e;
e = e->next;
}
return NULL;
}
/**
* wpa_blacklist_add - Add an BSSID to the blacklist
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID to be added to the blacklist
* Returns: Current blacklist count on success, -1 on failure
*
* This function adds the specified BSSID to the blacklist or increases the
* blacklist count if the BSSID was already listed. It should be called when
* an association attempt fails either due to the selected BSS rejecting
* association or due to timeout.
*
* This blacklist is used to force %wpa_supplicant to go through all available
* BSSes before retrying to associate with an BSS that rejected or timed out
* association. It does not prevent the listed BSS from being used; it only
* changes the order in which they are tried.
*/
int wpa_blacklist_add(struct wpa_supplicant *wpa_s, const u8 *bssid)
{
struct wpa_blacklist *e;
e = wpa_blacklist_get(wpa_s, bssid);
if (e) {
e->count++;
wpa_printf(MSG_DEBUG, "BSSID " MACSTR " blacklist count "
"incremented to %d",
MAC2STR(bssid), e->count);
return e->count;
}
e = os_zalloc(sizeof(*e));
if (e == NULL)
return -1;
os_memcpy(e->bssid, bssid, ETH_ALEN);
e->count = 1;
e->next = wpa_s->blacklist;
wpa_s->blacklist = e;
wpa_printf(MSG_DEBUG, "Added BSSID " MACSTR " into blacklist",
MAC2STR(bssid));
return e->count;
}
/**
* wpa_blacklist_del - Remove an BSSID from the blacklist
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID to be removed from the blacklist
* Returns: 0 on success, -1 on failure
*/
int wpa_blacklist_del(struct wpa_supplicant *wpa_s, const u8 *bssid)
{
struct wpa_blacklist *e, *prev = NULL;
e = wpa_s->blacklist;
while (e) {
if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0) {
if (prev == NULL) {
wpa_s->blacklist = e->next;
} else {
prev->next = e->next;
}
wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from "
"blacklist", MAC2STR(bssid));
os_free(e);
return 0;
}
prev = e;
e = e->next;
}
return -1;
}
/**
* wpa_blacklist_clear - Clear the blacklist of all entries
* @wpa_s: Pointer to wpa_supplicant data
*/
void wpa_blacklist_clear(struct wpa_supplicant *wpa_s)
{
struct wpa_blacklist *e, *prev;
e = wpa_s->blacklist;
wpa_s->blacklist = NULL;
while (e) {
prev = e;
e = e->next;
wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from "
"blacklist (clear)", MAC2STR(prev->bssid));
os_free(prev);
}
}