Split scan processing for RSN preauthentication into parts

This avoids passing the raw scan results into the RSN code and by
doing so, removes the only dependency on src/drivers from the
src/rsn_supp code (or from any src subdirectory for that matter).

src/rsn_supp/preauth.c

@@ -1,6 +1,6 @@
 /*
  * WPA Supplicant - RSN pre-authentication
- * Copyright (c) 2003-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2003-2009, 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
@@ -16,7 +16,6 @@
 
 #include "common.h"
 #include "wpa.h"
-#include "drivers/driver.h"
 #include "eloop.h"
 #include "l2_packet/l2_packet.h"
 #include "eapol_supp/eapol_supp_sm.h"
@@ -423,23 +422,18 @@ void pmksa_candidate_add(struct wpa_sm *sm, const u8 *bssid,
 /* TODO: schedule periodic scans if current AP supports preauth */
 
 /**
- * rsn_preauth_scan_results - Process scan results to find PMKSA candidates
+ * rsn_preauth_scan_results - Start processing scan results for canditates
  * @sm: Pointer to WPA state machine data from wpa_sm_init()
- * @results: Scan results
+ * Returns: 0 if ready to process results or -1 to skip processing
  *
- * This functions goes through the scan results and adds all suitable APs
+ * This functions is used to notify RSN code about start of new scan results
- * (Authenticators) into PMKSA candidate list.
+ * processing. The actual scan results will be provided by calling
+ * rsn_preauth_scan_result() for each BSS if this function returned 0.
  */
-void rsn_preauth_scan_results(struct wpa_sm *sm,
+int rsn_preauth_scan_results(struct wpa_sm *sm)
-			      struct wpa_scan_results *results)
 {
-	struct wpa_scan_res *r;
-	struct wpa_ie_data ie;
-	int i;
-	struct rsn_pmksa_cache_entry *pmksa;
-
 	if (sm->ssid_len == 0)
-		return;
+		return -1;
 
 	/*
 	 * TODO: is it ok to free all candidates? What about the entries
@@ -447,37 +441,41 @@ void rsn_preauth_scan_results(struct wpa_sm *sm,
 	 */
 	pmksa_candidate_free(sm);
 
-	for (i = results->num - 1; i >= 0; i--) {
+	return 0;
-		const u8 *ssid, *rsn;
-
-		r = results->res[i];
-
-		ssid = wpa_scan_get_ie(r, WLAN_EID_SSID);
-		if (ssid == NULL || ssid[1] != sm->ssid_len ||
-		    os_memcmp(ssid + 2, sm->ssid, ssid[1]) != 0)
-			continue;
-
-		if (os_memcmp(r->bssid, sm->bssid, ETH_ALEN) == 0)
-			continue;
-
-		rsn = wpa_scan_get_ie(r, WLAN_EID_RSN);
-		if (rsn == NULL || wpa_parse_wpa_ie(rsn, 2 + rsn[1], &ie))
-			continue;
-
-		pmksa = pmksa_cache_get(sm->pmksa, r->bssid, NULL);
-		if (pmksa &&
-		    (!pmksa->opportunistic ||
-		     !(ie.capabilities & WPA_CAPABILITY_PREAUTH)))
-			continue;
-
-		/*
-		 * Give less priority to candidates found from normal
-		 * scan results.
-		 */
-		pmksa_candidate_add(sm, r->bssid,
-				    PMKID_CANDIDATE_PRIO_SCAN,
-				    ie.capabilities & WPA_CAPABILITY_PREAUTH);
 }
+
+
+/**
+ * rsn_preauth_scan_result - Processing scan result for PMKSA canditates
+ * @sm: Pointer to WPA state machine data from wpa_sm_init()
+ *
+ * Add all suitable APs (Authenticators) from scan results into PMKSA
+ * candidate list.
+ */
+void rsn_preauth_scan_result(struct wpa_sm *sm, const u8 *bssid,
+			     const u8 *ssid, const u8 *rsn)
+{
+	struct wpa_ie_data ie;
+	struct rsn_pmksa_cache_entry *pmksa;
+
+	if (ssid[1] != sm->ssid_len ||
+	    os_memcmp(ssid + 2, sm->ssid, sm->ssid_len) != 0)
+		return; /* Not for the current SSID */
+
+	if (os_memcmp(bssid, sm->bssid, ETH_ALEN) == 0)
+		return; /* Ignore current AP */
+
+	if (wpa_parse_wpa_ie(rsn, 2 + rsn[1], &ie))
+		return;
+
+	pmksa = pmksa_cache_get(sm->pmksa, bssid, NULL);
+	if (pmksa && (!pmksa->opportunistic ||
+		      !(ie.capabilities & WPA_CAPABILITY_PREAUTH)))
+		return;
+
+	/* Give less priority to candidates found from normal scan results. */
+	pmksa_candidate_add(sm, bssid, PMKID_CANDIDATE_PRIO_SCAN,
+			    ie.capabilities & WPA_CAPABILITY_PREAUTH);
 }
 
 

src/rsn_supp/preauth.h

@@ -1,6 +1,6 @@
 /*
  * wpa_supplicant - WPA2/RSN pre-authentication functions
- * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2003-2009, 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
@@ -23,8 +23,9 @@ void pmksa_candidate_free(struct wpa_sm *sm);
 int rsn_preauth_init(struct wpa_sm *sm, const u8 *dst,
 		     struct eap_peer_config *eap_conf);
 void rsn_preauth_deinit(struct wpa_sm *sm);
-void rsn_preauth_scan_results(struct wpa_sm *sm,
+int rsn_preauth_scan_results(struct wpa_sm *sm);
-			      struct wpa_scan_results *results);
+void rsn_preauth_scan_result(struct wpa_sm *sm, const u8 *bssid,
+			     const u8 *ssid, const u8 *rsn);
 void pmksa_candidate_add(struct wpa_sm *sm, const u8 *bssid,
 			 int prio, int preauth);
 void rsn_preauth_candidate_process(struct wpa_sm *sm);
@@ -51,8 +52,14 @@ static inline int rsn_preauth_init(struct wpa_sm *sm, const u8 *dst,
 static inline void rsn_preauth_deinit(struct wpa_sm *sm)
 {
 }
-static inline void rsn_preauth_scan_results(struct wpa_sm *sm,
+
-					    struct wpa_scan_results *results)
+static inline int rsn_preauth_scan_results(struct wpa_sm *sm)
+{
+	return -1;
+}
+
+void rsn_preauth_scan_result(struct wpa_sm *sm, const u8 *bssid,
+			     const u8 *ssid, const u8 *rsn)
 {
 }
 

wpa_supplicant/events.c

@@ -1,6 +1,6 @@
 /*
  * WPA Supplicant - Driver event processing
- * Copyright (c) 2003-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2003-2009, 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
@@ -711,7 +711,6 @@ static void wpa_supplicant_connect(struct wpa_supplicant *wpa_s,
 		wpa_printf(MSG_DEBUG, "Already associated with the selected "
 			   "AP");
 	}
-	rsn_preauth_scan_results(wpa_s->wpa, wpa_s->scan_res);
 }
 
 
@@ -735,6 +734,34 @@ wpa_supplicant_pick_new_network(struct wpa_supplicant *wpa_s)
 }
 
 
+static void wpa_supplicant_rsn_preauth_scan_results(
+	struct wpa_supplicant *wpa_s)
+{
+	int i;
+
+	if (rsn_preauth_scan_results(wpa_s->wpa) < 0)
+		return;
+
+	for (i = wpa_s->scan_res->num - 1; i >= 0; i--) {
+		const u8 *ssid, *rsn;
+		struct wpa_scan_res *r;
+
+		r = wpa_s->scan_res->res[i];
+
+		ssid = wpa_scan_get_ie(r, WLAN_EID_SSID);
+		if (ssid == NULL)
+			continue;
+
+		rsn = wpa_scan_get_ie(r, WLAN_EID_RSN);
+		if (rsn == NULL)
+			continue;
+
+		rsn_preauth_scan_result(wpa_s->wpa, r->bssid, ssid, rsn);
+	}
+
+}
+
+
 static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s)
 {
 	struct wpa_scan_res *selected;
@@ -778,6 +805,8 @@ static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s)
 	if (bgscan_notify_scan(wpa_s) == 1)
 		return;
 
+	wpa_supplicant_rsn_preauth_scan_results(wpa_s);
+
 	selected = wpa_supplicant_pick_network(wpa_s, &ssid);
 	if (selected) {
 		wpa_supplicant_connect(wpa_s, selected, ssid);