Add max_num_sta config option for wpa_supplicant AP mode

This can be used to limit the number of stations allowed to be
connected to the AP.

wpa_supplicant/ap.c

@@ -178,6 +178,8 @@ static int wpa_supplicant_conf_ap(struct wpa_supplicant *wpa_s,
 	os_memcpy(bss->os_version, wpa_s->conf->os_version, 4);
 #endif /* CONFIG_WPS */
 
+	bss->max_num_sta = wpa_s->conf->max_num_sta;
+
 	return 0;
 }
 

wpa_supplicant/config.c

@@ -2146,6 +2146,7 @@ struct wpa_config * wpa_config_alloc_empty(const char *ctrl_interface,
 	config->p2p_go_intent = DEFAULT_P2P_GO_INTENT;
 	config->p2p_intra_bss = DEFAULT_P2P_INTRA_BSS;
 	config->bss_max_count = DEFAULT_BSS_MAX_COUNT;
+	config->max_num_sta = DEFAULT_MAX_NUM_STA;
 
 	if (ctrl_interface)
 		config->ctrl_interface = os_strdup(ctrl_interface);
@@ -2405,7 +2406,8 @@ static const struct global_parse_data global_fields[] = {
 #endif /* CONFIG_P2P */
 	{ FUNC(country), CFG_CHANGED_COUNTRY },
 	{ INT(bss_max_count), 0 },
-	{ INT_RANGE(filter_ssids, 0, 1), 0 }
+	{ INT_RANGE(filter_ssids, 0, 1), 0 },
+	{ INT(max_num_sta), 0 }
 };
 
 #undef FUNC

wpa_supplicant/config.h

@@ -25,6 +25,7 @@
 #define DEFAULT_P2P_GO_INTENT 7
 #define DEFAULT_P2P_INTRA_BSS 1
 #define DEFAULT_BSS_MAX_COUNT 200
+#define DEFAULT_MAX_NUM_STA 128
 
 #include "config_ssid.h"
 
@@ -378,6 +379,11 @@ struct wpa_config {
 	 */
 	int filter_ssids;
 
+	/**
+	 * max_num_sta - Maximum number of STAs in an AP/P2P GO
+	 */
+	unsigned int max_num_sta;
+
 	/**
 	 * changed_parameters - Bitmap of changed parameters since last update
 	 */

wpa_supplicant/config_file.c

@@ -685,6 +685,8 @@ static void wpa_config_write_global(FILE *f, struct wpa_config *config)
 		fprintf(f, "bss_max_count=%u\n", config->bss_max_count);
 	if (config->filter_ssids)
 		fprintf(f, "filter_ssids=%d\n", config->filter_ssids);
+	if (config->max_num_sta != DEFAULT_MAX_NUM_STA)
+		fprintf(f, "max_num_sta=%u\n", config->max_num_sta);
 }
 
 #endif /* CONFIG_NO_CONFIG_WRITE */

wpa_supplicant/config_winreg.c

@@ -265,6 +265,8 @@ static int wpa_config_read_global(struct wpa_config *config, HKEY hk)
 				  (int *) &config->bss_max_count);
 	wpa_config_read_reg_dword(hk, TEXT("filter_ssids"),
 				  &config->filter_ssids);
+	wpa_config_read_reg_dword(hk, TEXT("max_num_sta"),
+				  (int *) &config->max_num_sta);
 
 	return errors ? -1 : 0;
 }
@@ -601,6 +603,8 @@ static int wpa_config_write_global(struct wpa_config *config, HKEY hk)
 				   DEFAULT_BSS_MAX_COUNT);
 	wpa_config_write_reg_dword(hk, TEXT("filter_ssids"),
 				   config->filter_ssids, 0);
+	wpa_config_write_reg_dword(hk, TEXT("max_num_sta"),
+				   config->max_num_sta, DEFAULT_MAX_NUM_STA);
 
 	return 0;
 }