diff -up wpa_supplicant-0.6.8/src/drivers/driver.h.ap-stability wpa_supplicant-0.6.8/src/drivers/driver.h
--- wpa_supplicant-0.6.8/src/drivers/driver.h.ap-stability 2009-02-15 13:00:00.000000000 -0500
+++ wpa_supplicant-0.6.8/src/drivers/driver.h 2009-05-12 16:01:32.000000000 -0400
@@ -1017,6 +1017,21 @@ struct wpa_driver_ops {
* failure
*/
struct wpa_interface_info * (*get_interfaces)(void *global_priv);
+
+ /**
+ * get_signal_quality - Request signal quality of the current association
+ * @priv: private driver interface data
+ * @qual: signal "quality", perhaps including TX errors, missed beacons,
+ * etc. If not provided, set to 0.
+ * @max_qual: maximum possible signal quality. If not provided set to 0.
+ *
+ * This handler may be called at any time to retrieve the signal quality
+ * of the current association. If there is no association, the handler
+ * must return -1. If the signal level isn't known or is not provided,
+ * the handler must return -1.
+ * Returns: 0 on success, -1 on failure
+ */
+ int (*get_signal_quality)(void *priv, int *qual, int *max_qual);
};
/* Function to check whether a driver is for wired connections */
diff -up wpa_supplicant-0.6.8/src/drivers/driver_wext.c.ap-stability wpa_supplicant-0.6.8/src/drivers/driver_wext.c
--- wpa_supplicant-0.6.8/src/drivers/driver_wext.c.ap-stability 2009-05-12 16:01:32.000000000 -0400
+++ wpa_supplicant-0.6.8/src/drivers/driver_wext.c 2009-05-12 16:01:32.000000000 -0400
@@ -1615,6 +1615,10 @@ static int wpa_driver_wext_get_range(voi
if (range->enc_capa & IW_ENC_CAPA_4WAY_HANDSHAKE)
drv->capa.flags |= WPA_DRIVER_FLAGS_4WAY_HANDSHAKE;
+ drv->max_qual.qual = range->max_qual.qual;
+ drv->max_qual.level = range->max_qual.level;
+ drv->max_qual.updated = range->max_qual.updated;
+
wpa_printf(MSG_DEBUG, " capabilities: key_mgmt 0x%x enc 0x%x "
"flags 0x%x",
drv->capa.key_mgmt, drv->capa.enc, drv->capa.flags);
@@ -2244,6 +2248,51 @@ done:
}
+/**
+ * wpa_driver_wext_get_signal_quality - Get wireless signal quality, SIOCSIWSTATS
+ * @priv: Pointer to private wext data from wpa_driver_wext_init()
+ * @qual: signal quality
+ * @max_qual: maximum signal quality
+ * Returns: 0 on success, -1 on failure
+ */
+int wpa_driver_wext_get_signal_quality(void *priv, int *qual, int *max_qual)
+{
+ struct wpa_driver_wext_data *drv = priv;
+ struct iwreq iwr;
+ struct iw_statistics stats;
+ s8 level = 0;
+
+ os_memset(&iwr, 0, sizeof(iwr));
+ os_strlcpy(iwr.ifr_name, drv->ifname, IFNAMSIZ);
+
+ memset (&stats, 0, sizeof (stats));
+ iwr.u.data.pointer = &stats;
+ iwr.u.data.length = sizeof (stats);
+ iwr.u.data.flags = 1; /* Clear updated flag */
+
+ if (ioctl(drv->ioctl_sock, SIOCGIWSTATS, &iwr)) {
+ wpa_printf(MSG_DEBUG, "%s: IWSTATS returned error: %d",
+ __FUNCTION__, errno);
+ return -1;
+ }
+
+ if ( !(drv->max_qual.updated & IW_QUAL_LEVEL_INVALID)
+ && !(stats.qual.updated & IW_QUAL_LEVEL_INVALID)) {
+ level = stats.qual.level;
+ }
+
+ if ( !(drv->max_qual.updated & IW_QUAL_QUAL_INVALID)
+ && !(stats.qual.updated & IW_QUAL_QUAL_INVALID)) {
+ *qual = stats.qual.qual;
+ *max_qual = drv->max_qual.qual;
+ }
+
+ wpa_printf(MSG_DEBUG, "%s: level %d (%d), qual %d (%d)", __FUNCTION__,
+ level, drv->max_qual.level, *qual, drv->max_qual.qual);
+ return 0;
+}
+
+
static int wpa_driver_wext_pmksa(struct wpa_driver_wext_data *drv,
u32 cmd, const u8 *bssid, const u8 *pmkid)
{
@@ -2357,6 +2406,7 @@ const struct wpa_driver_ops wpa_driver_w
.deauthenticate = wpa_driver_wext_deauthenticate,
.disassociate = wpa_driver_wext_disassociate,
.set_mode = wpa_driver_wext_set_mode,
+ .get_signal_quality = wpa_driver_wext_get_signal_quality,
.associate = wpa_driver_wext_associate,
.set_auth_alg = wpa_driver_wext_set_auth_alg,
.init = wpa_driver_wext_init,
diff -up wpa_supplicant-0.6.8/src/drivers/driver_wext.h.ap-stability wpa_supplicant-0.6.8/src/drivers/driver_wext.h
--- wpa_supplicant-0.6.8/src/drivers/driver_wext.h.ap-stability 2009-02-15 13:00:00.000000000 -0500
+++ wpa_supplicant-0.6.8/src/drivers/driver_wext.h 2009-05-12 16:01:32.000000000 -0400
@@ -16,6 +16,7 @@
#define DRIVER_WEXT_H
#include <net/if.h>
+#include "wireless_copy.h"
struct wpa_driver_wext_data {
void *ctx;
@@ -43,6 +44,8 @@ struct wpa_driver_wext_data {
char mlmedev[IFNAMSIZ + 1];
int scan_complete_events;
+
+ struct iw_quality max_qual;
};
int wpa_driver_wext_get_ifflags(struct wpa_driver_wext_data *drv, int *flags);
diff -up wpa_supplicant-0.6.8/wpa_supplicant/events.c.ap-stability wpa_supplicant-0.6.8/wpa_supplicant/events.c
--- wpa_supplicant-0.6.8/wpa_supplicant/events.c.ap-stability 2009-05-12 16:01:32.000000000 -0400
+++ wpa_supplicant-0.6.8/wpa_supplicant/events.c 2009-05-12 16:19:06.000000000 -0400
@@ -371,9 +371,53 @@ static int wpa_supplicant_ssid_bss_match
}
+struct cur_ap {
+ u8 bssid[ETH_ALEN];
+ int qual;
+ int max_qual;
+};
+
+#define CUR_AP_THRESHOLD 50
+
+/* Return 1 if 'bss' should be used instead of the current association */
+static int
+bss_better_quality(struct wpa_scan_res *bss, struct cur_ap *cur)
+{
+ int cur_pqual, bss_pqual;
+
+ /* If the max quality is invalid, quality is pretty meaningless */
+ if (!cur->max_qual) {
+ wpa_printf(MSG_DEBUG, " no max quality");
+ return 1;
+ }
+
+ cur_pqual = (int) (((float) cur->qual / (float) cur->max_qual) * 100);
+ bss_pqual = (int) (((float) bss->qual / (float) cur->max_qual) * 100);
+
+ /* If 'bss' is the current associated BSS and it's still got OK quality,
+ * stick with it.
+ */
+ if (!os_memcmp(cur->bssid, bss->bssid, ETH_ALEN) && (cur_pqual >= CUR_AP_THRESHOLD)) {
+ wpa_printf(MSG_DEBUG, " matched associated BSSID");
+ return 1;
+ }
+
+ wpa_printf(MSG_DEBUG, " cur AP qual: %d candidate qual: %d", cur_pqual, bss_pqual);
+
+ /* Otherwise if the current association is worse than 50% quality and
+ * 'bss' is at least 15% better, then use 'bss'.
+ */
+ if ((cur_pqual < CUR_AP_THRESHOLD) && (bss_pqual >= cur_pqual + 15))
+ return 1;
+
+ return 0;
+}
+
+
static struct wpa_scan_res *
wpa_supplicant_select_bss_wpa(struct wpa_supplicant *wpa_s,
struct wpa_ssid *group,
+ struct cur_ap *cur,
struct wpa_ssid **selected_ssid)
{
struct wpa_ssid *ssid;
@@ -448,6 +492,12 @@ wpa_supplicant_select_bss_wpa(struct wpa
if (!wpa_supplicant_ssid_bss_match(wpa_s, ssid, bss))
continue;
+ if (cur && !bss_better_quality(bss, cur)) {
+ wpa_printf(MSG_DEBUG, " skip - "
+ "signal strength not high enough");
+ continue;
+ }
+
wpa_printf(MSG_DEBUG, " selected WPA AP "
MACSTR " ssid='%s'",
MAC2STR(bss->bssid),
@@ -464,6 +514,7 @@ wpa_supplicant_select_bss_wpa(struct wpa
static struct wpa_scan_res *
wpa_supplicant_select_bss_non_wpa(struct wpa_supplicant *wpa_s,
struct wpa_ssid *group,
+ struct cur_ap *cur,
struct wpa_ssid **selected_ssid)
{
struct wpa_ssid *ssid;
@@ -569,6 +620,12 @@ wpa_supplicant_select_bss_non_wpa(struct
continue;
}
+ if (cur && !bss_better_quality(bss, cur)) {
+ wpa_printf(MSG_DEBUG, " skip - "
+ "signal strength not high enough");
+ continue;
+ }
+
wpa_printf(MSG_DEBUG, " selected non-WPA AP "
MACSTR " ssid='%s'",
MAC2STR(bss->bssid),
@@ -584,21 +641,45 @@ wpa_supplicant_select_bss_non_wpa(struct
static struct wpa_scan_res *
wpa_supplicant_select_bss(struct wpa_supplicant *wpa_s, struct wpa_ssid *group,
- struct wpa_ssid **selected_ssid)
+ struct cur_ap *cur, struct wpa_ssid **selected_ssid)
{
struct wpa_scan_res *selected;
wpa_printf(MSG_DEBUG, "Selecting BSS from priority group %d",
group->priority);
+ if (cur) {
+ int found = 0, i;
+ struct wpa_scan_res *bss;
+
+ wpa_printf(MSG_DEBUG, "Try to find current BSSID "
+ "%02x:%02x:%02x:%02x:%02x:%02x",
+ cur->bssid[0], cur->bssid[1], cur->bssid[2],
+ cur->bssid[3], cur->bssid[4], cur->bssid[5]);
+ for (i = 0; i < wpa_s->scan_res->num; i++) {
+ bss = wpa_s->scan_res->res[i];
+ if (os_memcmp(bss->bssid, cur->bssid, ETH_ALEN) != 0) {
+ wpa_printf(MSG_DEBUG, " skip - "
+ "BSSID mismatch");
+ continue;
+ }
+ wpa_printf(MSG_DEBUG, " found");
+ found = 1;
+ break;
+ }
+
+ if (!found)
+ cur = NULL;
+ }
+
/* First, try to find WPA-enabled AP */
- selected = wpa_supplicant_select_bss_wpa(wpa_s, group, selected_ssid);
+ selected = wpa_supplicant_select_bss_wpa(wpa_s, group, cur, selected_ssid);
if (selected)
return selected;
/* If no WPA-enabled AP found, try to find non-WPA AP, if configuration
* allows this. */
- return wpa_supplicant_select_bss_non_wpa(wpa_s, group, selected_ssid);
+ return wpa_supplicant_select_bss_non_wpa(wpa_s, group, cur, selected_ssid);
}
@@ -607,6 +687,8 @@ static void wpa_supplicant_event_scan_re
int prio, timeout;
struct wpa_scan_res *selected = NULL;
struct wpa_ssid *ssid = NULL;
+ int qual = 0, max_qual = 0, qual_valid = 0, bssid_valid = 0, i;
+ struct cur_ap cur;
if (wpa_supplicant_get_scan_results(wpa_s) < 0) {
if (wpa_s->conf->ap_scan == 2)
@@ -635,10 +717,44 @@ static void wpa_supplicant_event_scan_re
wpa_s->disconnected)
return;
+ /* Get current driver BSSID and signal strength */
+ os_memset(&cur, 0, sizeof(cur));
+
+ for (i = 0; i < 4; i++) {
+ static u8 bad1[ETH_ALEN] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
+ static u8 bad2[ETH_ALEN] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
+ static u8 bad3[ETH_ALEN] = {0x44, 0x44, 0x44, 0x44, 0x44, 0x44};
+
+ if (wpa_drv_get_bssid(wpa_s, (u8 *) &cur.bssid) == 0) {
+ if (memcmp(cur.bssid, bad1, ETH_ALEN) &&
+ memcmp(cur.bssid, bad2, ETH_ALEN) &&
+ memcmp(cur.bssid, bad3, ETH_ALEN)) {
+ bssid_valid = 1;
+ break;
+ }
+ }
+ }
+
+ if (bssid_valid) {
+ for (i = 0; i < 4; i++) {
+ qual_valid = !wpa_drv_get_signal_quality(wpa_s, &qual, &max_qual);
+ if (qual_valid && qual) {
+ cur.qual = qual;
+ cur.max_qual = max_qual;
+ break;
+ }
+ }
+ }
+
+ wpa_printf(MSG_DEBUG, "%s: qual %d (%d) qv=%d bv=%d",
+ __FUNCTION__, qual, max_qual, qual_valid, bssid_valid);
+
while (selected == NULL) {
for (prio = 0; prio < wpa_s->conf->num_prio; prio++) {
selected = wpa_supplicant_select_bss(
- wpa_s, wpa_s->conf->pssid[prio], &ssid);
+ wpa_s, wpa_s->conf->pssid[prio],
+ (bssid_valid && qual_valid) ? &cur : NULL,
+ &ssid);
if (selected)
break;
}
diff -up wpa_supplicant-0.6.8/wpa_supplicant/wpa_supplicant_i.h.ap-stability wpa_supplicant-0.6.8/wpa_supplicant/wpa_supplicant_i.h
--- wpa_supplicant-0.6.8/wpa_supplicant/wpa_supplicant_i.h.ap-stability 2009-05-12 16:01:32.000000000 -0400
+++ wpa_supplicant-0.6.8/wpa_supplicant/wpa_supplicant_i.h 2009-05-12 16:01:33.000000000 -0400
@@ -485,6 +485,15 @@ static inline int wpa_drv_set_mode(struc
return 0;
}
+static inline int wpa_drv_get_signal_quality(struct wpa_supplicant *wpa_s,
+ int *qual, int *max_qual)
+{
+ if (wpa_s->driver->get_signal_quality) {
+ return wpa_s->driver->get_signal_quality(wpa_s->drv_priv, qual, max_qual);
+ }
+ return -1;
+}
+
static inline int wpa_drv_associate(struct wpa_supplicant *wpa_s,
struct wpa_driver_associate_params *params)
{