P2P: Allow multiple scan runs to find GO for p2p_connect join

If the GO is not found, we cannot send Provisioning Discovery Request
frame and cannot really connect anyway. Since the Provisioning
Discovery is a mandatory part, it is better to continue join-scan
until the GO is found instead of moving to the next step where
normal connection scan is used (PD would not be used from there).

Use a limit of 10 scan attempts for p2p_connect join to avoid getting
in infinite loop trying to join. If the GO is not found with those
scans, indicate failure (P2P-GROUP-FORMATION-FAILURE) and stop the
join attempt.

diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
index 758cc5d83eae03604866b1a91c413a0fe94bdc25..f9bf472a0bf8ed3ff204fa97db079aa3d54948e2 100644 (file)
--- a/wpa_supplicant/p2p_supplicant.c
+++ b/wpa_supplicant/p2p_supplicant.c
@@ -36,6 +36,13 @@
 #include "p2p_supplicant.h"
 
 
+/*
+ * How many times to try to scan to find the GO before giving up on join
+ * request.
+ */
+#define P2P_MAX_JOIN_SCAN_ATTEMPTS 10
+
+
 static void wpas_p2p_long_listen_timeout(void *eloop_ctx, void *timeout_ctx);
 static struct wpa_supplicant *
 wpas_p2p_get_group_iface(struct wpa_supplicant *wpa_s, int addr_allocated,
@@ -2413,6 +2420,22 @@ static int wpas_p2p_auth_go_neg(struct wpa_supplicant *wpa_s,
 }
 
 
+static void wpas_p2p_check_join_scan_limit(struct wpa_supplicant *wpa_s)
+{
+       wpa_s->p2p_join_scan_count++;
+       wpa_printf(MSG_DEBUG, "P2P: Join scan attempt %d",
+                  wpa_s->p2p_join_scan_count);
+       if (wpa_s->p2p_join_scan_count > P2P_MAX_JOIN_SCAN_ATTEMPTS) {
+               wpa_printf(MSG_DEBUG, "P2P: Failed to find GO " MACSTR
+                          " for join operationg - stop join attempt",
+                          MAC2STR(wpa_s->pending_join_iface_addr));
+               eloop_cancel_timeout(wpas_p2p_join_scan, wpa_s, NULL);
+               wpa_msg(wpa_s->parent, MSG_INFO,
+                       P2P_EVENT_GROUP_FORMATION_FAILURE);
+       }
+}
+
+
 static void wpas_p2p_scan_res_join(struct wpa_supplicant *wpa_s,
                                   struct wpa_scan_results *scan_res)
 {
@@ -2484,8 +2507,11 @@ static void wpas_p2p_scan_res_join(struct wpa_supplicant *wpa_s,
                return;
        }
 
-       wpa_printf(MSG_DEBUG, "P2P: Target BSS/GO not yet in BSS table - "
-                  "cannot send Provision Discovery Request");
+       wpa_printf(MSG_DEBUG, "P2P: Failed to find BSS/GO - try again later");
+       eloop_cancel_timeout(wpas_p2p_join_scan, wpa_s, NULL);
+       eloop_register_timeout(1, 0, wpas_p2p_join_scan, wpa_s, NULL);
+       wpas_p2p_check_join_scan_limit(wpa_s);
+       return;
 
 start:
        /* Start join operation immediately */
@@ -2546,6 +2572,7 @@ static void wpas_p2p_join_scan(void *eloop_ctx, void *timeout_ctx)
                           "try again later");
                eloop_cancel_timeout(wpas_p2p_join_scan, wpa_s, NULL);
                eloop_register_timeout(1, 0, wpas_p2p_join_scan, wpa_s, NULL);
+               wpas_p2p_check_join_scan_limit(wpa_s);
        }
 }
 
@@ -2564,6 +2591,7 @@ static int wpas_p2p_join(struct wpa_supplicant *wpa_s, const u8 *iface_addr,
        /* Make sure we are not running find during connection establishment */
        wpas_p2p_stop_find(wpa_s);
 
+       wpa_s->p2p_join_scan_count = 0;
        wpas_p2p_join_scan(wpa_s, NULL);
        return 0;
 }

diff --git a/wpa_supplicant/wpa_supplicant_i.h b/wpa_supplicant/wpa_supplicant_i.h
index 13abea631d75ad8ef88002e1c38f76c69347fb15..853968ce7574e60943ae267392138fc9218e706c 100644 (file)
--- a/wpa_supplicant/wpa_supplicant_i.h
+++ b/wpa_supplicant/wpa_supplicant_i.h
@@ -492,6 +492,7 @@ struct wpa_supplicant {
        u8 pending_join_iface_addr[ETH_ALEN];
        u8 pending_join_dev_addr[ETH_ALEN];
        int pending_join_wps_method;
+       int p2p_join_scan_count;
        unsigned int roc_waiting_drv_freq;
        int force_long_sd;