[PATCH] supplicant: Allow disabling reassoc based on scan results.

[greearb at candelatech.com]

From: Ben Greear <greearb at candelatech.com>

This gives configurable control over whether to consider
roaming based on scan results.  I find this useful when
doing explicit roaming tests, where I do not want scan
requests to cause the roam automatically.

Signed-off-by: Ben Greear <greearb at candelatech.com>
---
 wpa_supplicant/config.c | 6 ++++++
 wpa_supplicant/config.h | 9 +++++++++
 wpa_supplicant/events.c | 6 ++++++
 3 files changed, 21 insertions(+)

diff --git a/wpa_supplicant/config.c b/wpa_supplicant/config.c
index 83703a0..298d910 100644
--- a/wpa_supplicant/config.c
+++ b/wpa_supplicant/config.c
@@ -3644,6 +3644,9 @@ struct wpa_config * wpa_config_alloc_empty(const char *ctrl_interface,
 	if (driver_param)
 		config->driver_param = os_strdup(driver_param);
 
+#ifndef CONFIG_NO_ROAMING
+	config->disable_ess_roaming = DEFAULT_DISABLE_ESS_ROAMING;
+#endif
 	config->concurrent_assoc_ok = DEFAULT_CONCURRENT_ASSOC_OK;
 	config->accept_external_scan_results = DEFAULT_ACCEPT_EXTERNAL_SCAN_RESULTS;
 
@@ -4335,6 +4338,9 @@ static const struct global_parse_data global_fields[] = {
 	{ INT(sched_scan_interval), 0 },
 	{ INT(tdls_external_control), 0},
 	{ STR(osu_dir), 0 },
+#ifndef CONFIG_NO_ROAMING
+	{ INT(disable_ess_roaming), 0 },
+#endif
 	{ INT(concurrent_assoc_ok), 0 },
 	{ INT(accept_external_scan_results), 0 },
 	{ STR(wowlan_triggers), 0 },
diff --git a/wpa_supplicant/config.h b/wpa_supplicant/config.h
index 81ed410..b04f4a5 100644
--- a/wpa_supplicant/config.h
+++ b/wpa_supplicant/config.h
@@ -33,6 +33,7 @@
 #define DEFAULT_BSS_EXPIRATION_SCAN_COUNT 2
 #define DEFAULT_MIN_SCAN_GAP 0
 #define DEFAULT_MAX_ASSOC_PER_SCAN 25
+#define DEFAULT_DISABLE_ESS_ROAMING 0
 #define DEFAULT_CONCURRENT_ASSOC_OK 0
 #define DEFAULT_ACCEPT_EXTERNAL_SCAN_RESULTS 0
 #define DEFAULT_MAX_NUM_STA 128
@@ -857,6 +858,14 @@ struct wpa_config {
 	 */
 	unsigned int changed_parameters;
 
+#ifndef CONFIG_NO_ROAMING
+	/* If CONFIG_NO_ROAMING is not enabled, then scan results will
+	 * be used to automatically roam.  Allow disabling this automated
+	 * roaming without having to re-build the binary.
+	 */
+	int disable_ess_roaming;
+#endif
+
 	/* By default, scans are no longer shared once one of the stations starts
 	 * to associate.  This makes bringing up lots of vifs take a long time.
 	 * This override below lets us propagate scans even if a station is
diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index 1adf57d..2d2c29e 100644
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -1391,6 +1391,12 @@ static int wpa_supplicant_need_to_roam(struct wpa_supplicant *wpa_s,
 		return 1; /* current BSS not seen in the last scan */
 
 #ifndef CONFIG_NO_ROAMING
+	if (wpa_s->conf->disable_ess_roaming) {
+		wpa_dbg(wpa_s, MSG_DEBUG,
+			"NOT considering within-ESS reassociation, disable_ess_roaming is true");
+		return 0;
+	}
+
 	wpa_dbg(wpa_s, MSG_DEBUG, "Considering within-ESS reassociation");
 	wpa_dbg(wpa_s, MSG_DEBUG, "Current BSS: " MACSTR
 		" level=%d snr=%d est_throughput=%u",
-- 
1.9.3