Merge WPA and non-WPA network selection routines

This removes quite a bit of duplicated code and allows network block
priority configuration to be used to prefer unprotected networks and
also allows use on open network with good signal strength even if
scan results show a protected network with marginal signal strength
that does not allow it to be used.

wpa_supplicant/events.c

@@ -411,240 +411,119 @@ static int freq_allowed(int *freqs, int freq)
 }
 
 
-static struct wpa_bss *
-wpa_supplicant_select_bss_wpa(struct wpa_supplicant *wpa_s,
-			      struct wpa_scan_results *scan_res,
-			      struct wpa_ssid *group,
-			      struct wpa_ssid **selected_ssid)
+static struct wpa_ssid * wpa_scan_res_match(struct wpa_supplicant *wpa_s,
+					    int i, struct wpa_scan_res *bss,
+					    struct wpa_ssid *group)
 {
-	struct wpa_ssid *ssid;
-	struct wpa_scan_res *bss;
-	size_t i;
+	const u8 *ssid_;
+	u8 wpa_ie_len, rsn_ie_len, ssid_len;
+	int wpa;
 	struct wpa_blacklist *e;
 	const u8 *ie;
+	struct wpa_ssid *ssid;
 
-	wpa_printf(MSG_DEBUG, "Try to find WPA-enabled AP");
-	for (i = 0; i < scan_res->num; i++) {
-		const u8 *ssid_;
-		u8 wpa_ie_len, rsn_ie_len, ssid_len;
-		bss = scan_res->res[i];
+	ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
+	ssid_ = ie ? ie + 2 : (u8 *) "";
+	ssid_len = ie ? ie[1] : 0;
 
-		ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
-		ssid_ = ie ? ie + 2 : (u8 *) "";
-		ssid_len = ie ? ie[1] : 0;
+	ie = wpa_scan_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE);
+	wpa_ie_len = ie ? ie[1] : 0;
 
-		ie = wpa_scan_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE);
-		wpa_ie_len = ie ? ie[1] : 0;
+	ie = wpa_scan_get_ie(bss, WLAN_EID_RSN);
+	rsn_ie_len = ie ? ie[1] : 0;
 
-		ie = wpa_scan_get_ie(bss, WLAN_EID_RSN);
-		rsn_ie_len = ie ? ie[1] : 0;
+	wpa_printf(MSG_DEBUG, "%d: " MACSTR " ssid='%s' "
+		   "wpa_ie_len=%u rsn_ie_len=%u caps=0x%x level=%d%s",
+		   i, MAC2STR(bss->bssid), wpa_ssid_txt(ssid_, ssid_len),
+		   wpa_ie_len, rsn_ie_len, bss->caps, bss->level,
+		   wpa_scan_get_vendor_ie(bss, WPS_IE_VENDOR_TYPE) ?
+		   " wps" : "");
 
-		wpa_printf(MSG_DEBUG, "%d: " MACSTR " ssid='%s' "
-			   "wpa_ie_len=%u rsn_ie_len=%u caps=0x%x level=%d%s",
-			   (int) i, MAC2STR(bss->bssid),
-			   wpa_ssid_txt(ssid_, ssid_len),
-			   wpa_ie_len, rsn_ie_len, bss->caps, bss->level,
-			   wpa_scan_get_vendor_ie(bss, WPS_IE_VENDOR_TYPE) ?
-			   " wps" : "");
-
-		e = wpa_blacklist_get(wpa_s, bss->bssid);
-		if (e && e->count > 1) {
-			wpa_printf(MSG_DEBUG, "   skip - blacklisted");
-			continue;
-		}
+	e = wpa_blacklist_get(wpa_s, bss->bssid);
+	if (e && e->count > 1) {
+		wpa_printf(MSG_DEBUG, "   skip - blacklisted");
+		return 0;
+	}
 
-		if (ssid_len == 0) {
-			wpa_printf(MSG_DEBUG, "   skip - SSID not known");
-			continue;
-		}
+	if (ssid_len == 0) {
+		wpa_printf(MSG_DEBUG, "   skip - SSID not known");
+		return 0;
+	}
 
-		if (wpa_ie_len == 0 && rsn_ie_len == 0) {
-			wpa_printf(MSG_DEBUG, "   skip - no WPA/RSN IE");
-			continue;
-		}
+	wpa = wpa_ie_len > 0 || rsn_ie_len > 0;
 
-		for (ssid = group; ssid; ssid = ssid->pnext) {
-			int check_ssid = 1;
+	for (ssid = group; ssid; ssid = ssid->pnext) {
+		int check_ssid = wpa ? 1 : (ssid->ssid_len != 0);
 
-			if (ssid->disabled) {
-				wpa_printf(MSG_DEBUG, "   skip - disabled");
-				continue;
-			}
+		if (ssid->disabled) {
+			wpa_printf(MSG_DEBUG, "   skip - disabled");
+			return 0;
+		}
 
 #ifdef CONFIG_WPS
+		if (wpa && ssid->ssid_len == 0 &&
+		    wpas_wps_ssid_wildcard_ok(wpa_s, ssid, bss))
+			check_ssid = 0;
+
+		if (!wpa && (ssid->key_mgmt & WPA_KEY_MGMT_WPS)) {
+			/* Only allow wildcard SSID match if an AP
+			 * advertises active WPS operation that matches
+			 * with our mode. */
+			check_ssid = 1;
 			if (ssid->ssid_len == 0 &&
 			    wpas_wps_ssid_wildcard_ok(wpa_s, ssid, bss))
 				check_ssid = 0;
+		}
 #endif /* CONFIG_WPS */
 
-			if (check_ssid &&
-			    (ssid_len != ssid->ssid_len ||
-			     os_memcmp(ssid_, ssid->ssid, ssid_len) != 0)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "SSID mismatch");
-				continue;
-			}
-
-			if (ssid->bssid_set &&
-			    os_memcmp(bss->bssid, ssid->bssid, ETH_ALEN) != 0)
-			{
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "BSSID mismatch");
-				continue;
-			}
-
-			if (!wpa_supplicant_ssid_bss_match(wpa_s, ssid, bss))
-				continue;
-
-			if (!freq_allowed(ssid->freq_list, bss->freq)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "frequency not allowed");
-				continue;
-			}
-
-			wpa_printf(MSG_DEBUG, "   selected WPA AP "
-				   MACSTR " ssid='%s'",
-				   MAC2STR(bss->bssid),
-				   wpa_ssid_txt(ssid_, ssid_len));
-			*selected_ssid = ssid;
-			return wpa_bss_get(wpa_s, bss->bssid, ssid_, ssid_len);
+		if (check_ssid &&
+		    (ssid_len != ssid->ssid_len ||
+		     os_memcmp(ssid_, ssid->ssid, ssid_len) != 0)) {
+			wpa_printf(MSG_DEBUG, "   skip - SSID mismatch");
+			return 0;
 		}
-	}
-
-	return NULL;
-}
 
+		if (ssid->bssid_set &&
+		    os_memcmp(bss->bssid, ssid->bssid, ETH_ALEN) != 0) {
+			wpa_printf(MSG_DEBUG, "   skip - BSSID mismatch");
+			return 0;
+		}
 
-static struct wpa_bss *
-wpa_supplicant_select_bss_non_wpa(struct wpa_supplicant *wpa_s,
-				  struct wpa_scan_results *scan_res,
-				  struct wpa_ssid *group,
-				  struct wpa_ssid **selected_ssid)
-{
-	struct wpa_ssid *ssid;
-	struct wpa_scan_res *bss;
-	size_t i;
-	struct wpa_blacklist *e;
-	const u8 *ie;
-
-	wpa_printf(MSG_DEBUG, "Try to find non-WPA AP");
-	for (i = 0; i < scan_res->num; i++) {
-		const u8 *ssid_;
-		u8 wpa_ie_len, rsn_ie_len, ssid_len;
-		bss = scan_res->res[i];
-
-		ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
-		ssid_ = ie ? ie + 2 : (u8 *) "";
-		ssid_len = ie ? ie[1] : 0;
-
-		ie = wpa_scan_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE);
-		wpa_ie_len = ie ? ie[1] : 0;
-
-		ie = wpa_scan_get_ie(bss, WLAN_EID_RSN);
-		rsn_ie_len = ie ? ie[1] : 0;
-
-		wpa_printf(MSG_DEBUG, "%d: " MACSTR " ssid='%s' "
-			   "wpa_ie_len=%u rsn_ie_len=%u caps=0x%x",
-			   (int) i, MAC2STR(bss->bssid),
-			   wpa_ssid_txt(ssid_, ssid_len),
-			   wpa_ie_len, rsn_ie_len, bss->caps);
+		if (wpa && !wpa_supplicant_ssid_bss_match(wpa_s, ssid, bss))
+			return 0;
 
-		e = wpa_blacklist_get(wpa_s, bss->bssid);
-		if (e && e->count > 1) {
-			wpa_printf(MSG_DEBUG, "   skip - blacklisted");
-			continue;
+		if (!wpa &&
+		    !(ssid->key_mgmt & WPA_KEY_MGMT_NONE) &&
+		    !(ssid->key_mgmt & WPA_KEY_MGMT_WPS) &&
+		    !(ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA)) {
+			wpa_printf(MSG_DEBUG, "   skip - non-WPA network not "
+				   "allowed");
+			return 0;
 		}
 
-		if (ssid_len == 0) {
-			wpa_printf(MSG_DEBUG, "   skip - SSID not known");
-			continue;
+		if (!wpa && !wpa_supplicant_match_privacy(bss, ssid)) {
+			wpa_printf(MSG_DEBUG, "   skip - privacy mismatch");
+			return 0;
 		}
 
-		for (ssid = group; ssid; ssid = ssid->pnext) {
-			int check_ssid = ssid->ssid_len != 0;
-
-			if (ssid->disabled) {
-				wpa_printf(MSG_DEBUG, "   skip - disabled");
-				continue;
-			}
-
-#ifdef CONFIG_WPS
-			if (ssid->key_mgmt & WPA_KEY_MGMT_WPS) {
-				/* Only allow wildcard SSID match if an AP
-				 * advertises active WPS operation that matches
-				 * with our mode. */
-				check_ssid = 1;
-				if (ssid->ssid_len == 0 &&
-				    wpas_wps_ssid_wildcard_ok(wpa_s, ssid,
-							      bss))
-					check_ssid = 0;
-			}
-#endif /* CONFIG_WPS */
-
-			if (check_ssid &&
-			    (ssid_len != ssid->ssid_len ||
-			     os_memcmp(ssid_, ssid->ssid, ssid_len) != 0)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "SSID mismatch");
-				continue;
-			}
-
-			if (ssid->bssid_set &&
-			    os_memcmp(bss->bssid, ssid->bssid, ETH_ALEN) != 0)
-			{
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "BSSID mismatch");
-				continue;
-			}
-
-			if (!(ssid->key_mgmt & WPA_KEY_MGMT_NONE) &&
-			    !(ssid->key_mgmt & WPA_KEY_MGMT_WPS) &&
-			    !(ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA))
-			{
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "non-WPA network not allowed");
-				continue;
-			}
-
-			if ((ssid->key_mgmt &
-			     (WPA_KEY_MGMT_IEEE8021X | WPA_KEY_MGMT_PSK |
-			      WPA_KEY_MGMT_FT_IEEE8021X | WPA_KEY_MGMT_FT_PSK |
-			      WPA_KEY_MGMT_IEEE8021X_SHA256 |
-			      WPA_KEY_MGMT_PSK_SHA256)) &&
-			    (wpa_ie_len != 0 || rsn_ie_len != 0)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "WPA network");
-				continue;
-			}
-
-			if (!wpa_supplicant_match_privacy(bss, ssid)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "privacy mismatch");
-				continue;
-			}
-
-			if (bss->caps & IEEE80211_CAP_IBSS) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "IBSS (adhoc) network");
-				continue;
-			}
-
-			if (!freq_allowed(ssid->freq_list, bss->freq)) {
-				wpa_printf(MSG_DEBUG, "   skip - "
-					   "frequency not allowed");
-				continue;
-			}
+		if (!wpa && (bss->caps & IEEE80211_CAP_IBSS)) {
+			wpa_printf(MSG_DEBUG, "   skip - IBSS (adhoc) "
+				   "network");
+			return 0;
+		}
 
-			wpa_printf(MSG_DEBUG, "   selected non-WPA AP "
-				   MACSTR " ssid='%s'",
-				   MAC2STR(bss->bssid),
-				   wpa_ssid_txt(ssid_, ssid_len));
-			*selected_ssid = ssid;
-			return wpa_bss_get(wpa_s, bss->bssid, ssid_, ssid_len);
+		if (!freq_allowed(ssid->freq_list, bss->freq)) {
+			wpa_printf(MSG_DEBUG, "   skip - frequency not "
+				   "allowed");
+			return 0;
 		}
+
+		/* Matching configuration found */
+		return ssid;
 	}
 
-	return NULL;
+	/* No matching configuration found */
+	return 0;
 }
 
 
@@ -654,21 +533,30 @@ wpa_supplicant_select_bss(struct wpa_supplicant *wpa_s,
 			  struct wpa_ssid *group,
 			  struct wpa_ssid **selected_ssid)
 {
-	struct wpa_bss *selected;
+	size_t i;
 
 	wpa_printf(MSG_DEBUG, "Selecting BSS from priority group %d",
 		   group->priority);
 
-	/* First, try to find WPA-enabled AP */
-	selected = wpa_supplicant_select_bss_wpa(wpa_s, scan_res, group,
-						 selected_ssid);
-	if (selected)
-		return selected;
+	for (i = 0; i < scan_res->num; i++) {
+		struct wpa_scan_res *bss = scan_res->res[i];
+		const u8 *ie, *ssid;
+		u8 ssid_len;
+
+		*selected_ssid = wpa_scan_res_match(wpa_s, i, bss, group);
+		if (!*selected_ssid)
+			continue;
+
+		ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
+		ssid = ie ? ie + 2 : (u8 *) "";
+		ssid_len = ie ? ie[1] : 0;
+
+		wpa_printf(MSG_DEBUG, "   selected BSS " MACSTR " ssid='%s'",
+			   MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
+		return wpa_bss_get(wpa_s, bss->bssid, ssid, ssid_len);
+	}
 
-	/* 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, scan_res, group,
-						 selected_ssid);
+	return NULL;
 }