P2P: Provide better failure reason for group formation errors

I was playing with the DBUS P2P interface of wpa_supplicant, and it's
hard to know what's going on when you get a group formation failure with
empty messages, to the point I usually need to resort to debugging
wpa_supplicant itself.

Provide meaningful failure reasons for these errors.

Signed-off-by: Emilio Cobos Álvarez <emilio@crisal.io>

diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
index e084a886fcaed27d3a0043448945ea35517ca687..b589707e69809a91738bc9b8d7cac77ac183875b 100644 (file)
--- a/wpa_supplicant/p2p_supplicant.c
+++ b/wpa_supplicant/p2p_supplicant.c
@@ -153,7 +153,8 @@ static void wpas_p2p_group_deinit(struct wpa_supplicant *wpa_s);
 static int wpas_p2p_add_group_interface(struct wpa_supplicant *wpa_s,
                                        enum wpa_driver_if_type type);
 static void wpas_p2p_group_formation_failed(struct wpa_supplicant *wpa_s,
-                                           int already_deleted);
+                                           int already_deleted,
+                                           const char *reason);
 static void wpas_p2p_optimize_listen_channel(struct wpa_supplicant *wpa_s,
                                             struct wpa_used_freq_data *freqs,
                                             unsigned int num);
@@ -1013,7 +1014,7 @@ static int wpas_p2p_group_delete(struct wpa_supplicant *wpa_s,
                wpa_printf(MSG_DEBUG, "P2P: Cancelled P2P group formation "
                           "timeout");
                wpa_s->p2p_in_provisioning = 0;
-               wpas_p2p_group_formation_failed(wpa_s, 1);
+               wpas_p2p_group_formation_failed(wpa_s, 1, reason);
        }
 
        wpa_s->p2p_in_invitation = 0;
@@ -1546,7 +1547,8 @@ static int wpas_p2p_store_go_identity(struct wpa_supplicant *wpa_s,
 
 
 static void wpas_group_formation_completed(struct wpa_supplicant *wpa_s,
-                                          int success, int already_deleted)
+                                          int already_deleted,
+                                          const char *failure_reason)
 {
        struct wpa_ssid *ssid;
        int client;
@@ -1563,7 +1565,7 @@ static void wpas_group_formation_completed(struct wpa_supplicant *wpa_s,
        if (wpa_s->p2p_go_group_formation_completed) {
                wpa_s->global->p2p_group_formation = NULL;
                wpa_s->p2p_in_provisioning = 0;
-       } else if (wpa_s->p2p_in_provisioning && !success) {
+       } else if (wpa_s->p2p_in_provisioning && failure_reason) {
                wpa_msg(wpa_s, MSG_DEBUG,
                        "P2P: Stop provisioning state due to failure");
                wpa_s->p2p_in_provisioning = 0;
@@ -1572,10 +1574,10 @@ static void wpas_group_formation_completed(struct wpa_supplicant *wpa_s,
        wpa_s->p2p_retry_limit = 0;
        wpa_s->group_formation_reported = 1;
 
-       if (!success) {
+       if (failure_reason) {
                wpa_msg_global(wpa_s->p2pdev, MSG_INFO,
                               P2P_EVENT_GROUP_FORMATION_FAILURE);
-               wpas_notify_p2p_group_formation_failure(wpa_s, "");
+               wpas_notify_p2p_group_formation_failure(wpa_s, failure_reason);
                if (already_deleted)
                        return;
                wpas_p2p_group_delete(wpa_s,
@@ -2333,7 +2335,7 @@ static void p2p_go_configured(void *ctx, void *data)
        }
 
        if (params->p2p2) {
-               wpas_group_formation_completed(wpa_s, 1, 0);
+               wpas_group_formation_completed(wpa_s, 0, NULL);
                wpa_printf(MSG_DEBUG,
                           "P2P2: Group formation completed - first connection in progress");
                goto out;
@@ -2814,18 +2816,25 @@ static void wpas_p2p_group_formation_timeout(void *eloop_ctx,
 #endif /* CONFIG_PASN */
 
        wpa_printf(MSG_DEBUG, "P2P: Group Formation timed out");
-       wpas_p2p_group_formation_failed(wpa_s, 0);
+       wpas_p2p_group_formation_failed(wpa_s, 0, "Group formation timed out");
 }
 
 
 static void wpas_p2p_group_formation_failed(struct wpa_supplicant *wpa_s,
-                                           int already_deleted)
+                                           int already_deleted,
+                                           const char *reason)
 {
+        /* reason == NULL would indicate success in
+         * wpas_group_formation_completed(), so make sure that is not the case
+         * here. */
+       if (!reason)
+               reason = "";
+
        eloop_cancel_timeout(wpas_p2p_group_formation_timeout,
                             wpa_s->p2pdev, NULL);
        if (wpa_s->global->p2p)
                p2p_group_formation_failed(wpa_s->global->p2p);
-       wpas_group_formation_completed(wpa_s, 0, already_deleted);
+       wpas_group_formation_completed(wpa_s, already_deleted, reason);
 }
 
 
@@ -2983,7 +2992,8 @@ static void wpas_go_neg_completed(void *ctx, struct p2p_go_neg_results *res)
                        wpas_p2p_remove_pending_group_interface(wpa_s);
                        eloop_cancel_timeout(wpas_p2p_long_listen_timeout,
                                             wpa_s, NULL);
-                       wpas_p2p_group_formation_failed(wpa_s, 1);
+                       wpas_p2p_group_formation_failed(wpa_s, 1,
+                                                       "Could not initialize group interface");
                        return;
                }
                os_memset(wpa_s->pending_interface_addr, 0, ETH_ALEN);
@@ -8321,7 +8331,7 @@ void wpas_p2p_wps_success(struct wpa_supplicant *wpa_s, const u8 *peer_addr,
        }
        if (wpa_s->global->p2p)
                p2p_wps_success_cb(wpa_s->global->p2p, peer_addr);
-       wpas_group_formation_completed(wpa_s, 1, 0);
+       wpas_group_formation_completed(wpa_s, 0, NULL);
 }
 
 
@@ -9445,7 +9455,7 @@ static int wpas_p2p_notif_pbc_overlap(struct wpa_supplicant *wpa_s)
                   "session overlap");
        if (wpa_s != wpa_s->p2pdev)
                wpa_msg_ctrl(wpa_s->p2pdev, MSG_INFO, WPS_EVENT_OVERLAP);
-       wpas_p2p_group_formation_failed(wpa_s, 0);
+       wpas_p2p_group_formation_failed(wpa_s, 0, "WPS PBC session overlap");
        return 1;
 }
 
@@ -9554,7 +9564,8 @@ int wpas_p2p_cancel(struct wpa_supplicant *wpa_s)
                        eloop_cancel_timeout(wpas_p2p_group_formation_timeout,
                                             wpa_s->p2pdev, NULL);
                        if (wpa_s->p2p_in_provisioning) {
-                               wpas_group_formation_completed(wpa_s, 0, 0);
+                               wpas_group_formation_completed(wpa_s, 0,
+                                                              "Canceled");
                                break;
                        }
                        wpas_p2p_group_delete(wpa_s,
@@ -9564,7 +9575,7 @@ int wpas_p2p_cancel(struct wpa_supplicant *wpa_s)
                        wpa_printf(MSG_DEBUG, "P2P: Interface %s in invitation found - cancelling",
                                   wpa_s->ifname);
                        found = 1;
-                       wpas_p2p_group_formation_failed(wpa_s, 0);
+                       wpas_p2p_group_formation_failed(wpa_s, 0, "Canceled");
                        break;
                }
        }
@@ -9813,7 +9824,7 @@ void wpas_p2p_notify_ap_sta_authorized(struct wpa_supplicant *wpa_s,
                         */
                        if (wpa_s->global->p2p)
                                p2p_wps_success_cb(wpa_s->global->p2p, addr);
-                       wpas_group_formation_completed(wpa_s, 1, 0);
+                       wpas_group_formation_completed(wpa_s, 0, NULL);
                }
        }
        if (!wpa_s->p2p_go_group_formation_completed) {