DFS: Handle pre-CAC expired event

As FCC DFS requirement does not explicitly mention about the validity of
the (pre-)CAC when channel is switched, it is safe to assume that the
pre-CAC result will not be valid once the CAC completed channel is
switched or radar detection is not active on the (CAC completed) channel
within a time period which is allowed (10 seconds - channel switch time)
as per FCC DFS requirement.

Use the new driver event to allow the driver to notify expiry of the CAC
result on a channel. Move the DFS state of the channel to 'usable' when
processing pre-CAC expired event.  This means any future operation on
that channel will require a new CAC to be completed. This event is
applicable only when DFS is not offloaded to the kernel driver.

Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qti.qualcomm.com>

diff --git a/src/ap/dfs.c b/src/ap/dfs.c
index 23f265d641f12d66f846546a569d2da953bd07f8..295720100e16c35ed173169b2b840a504ed045c9 100644 (file)
--- a/src/ap/dfs.c
+++ b/src/ap/dfs.c
@@ -1,7 +1,7 @@
 /*
  * DFS - Dynamic Frequency Selection
  * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
- * Copyright (c) 2013-2015, Qualcomm Atheros, Inc.
+ * Copyright (c) 2013-2017, Qualcomm Atheros, Inc.
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
@@ -806,6 +806,25 @@ int hostapd_dfs_complete_cac(struct hostapd_iface *iface, int success, int freq,
 }
 
 
+int hostapd_dfs_pre_cac_expired(struct hostapd_iface *iface, int freq,
+                               int ht_enabled, int chan_offset, int chan_width,
+                               int cf1, int cf2)
+{
+       wpa_msg(iface->bss[0]->msg_ctx, MSG_INFO, DFS_EVENT_PRE_CAC_EXPIRED
+               "freq=%d ht_enabled=%d chan_offset=%d chan_width=%d cf1=%d cf2=%d",
+               freq, ht_enabled, chan_offset, chan_width, cf1, cf2);
+
+       /* Proceed only if DFS is not offloaded to the driver */
+       if (iface->drv_flags & WPA_DRIVER_FLAGS_DFS_OFFLOAD)
+               return 0;
+
+       set_dfs_state(iface, freq, ht_enabled, chan_offset, chan_width,
+                     cf1, cf2, HOSTAPD_CHAN_DFS_USABLE);
+
+       return 0;
+}
+
+
 static int hostapd_dfs_start_channel_switch_cac(struct hostapd_iface *iface)
 {
        struct hostapd_channel_data *channel;

diff --git a/src/ap/dfs.h b/src/ap/dfs.h
index be8c0e6001c9579cd886c919417ab6e3f0effb1e..f0fa6f688037deefae385d80da8376800c818d9f 100644 (file)
--- a/src/ap/dfs.h
+++ b/src/ap/dfs.h
@@ -1,7 +1,7 @@
 /*
  * DFS - Dynamic Frequency Selection
  * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
- * Copyright (c) 2013, Qualcomm Atheros, Inc.
+ * Copyright (c) 2013-2017, Qualcomm Atheros, Inc.
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
@@ -14,6 +14,9 @@ int hostapd_handle_dfs(struct hostapd_iface *iface);
 int hostapd_dfs_complete_cac(struct hostapd_iface *iface, int success, int freq,
                             int ht_enabled, int chan_offset, int chan_width,
                             int cf1, int cf2);
+int hostapd_dfs_pre_cac_expired(struct hostapd_iface *iface, int freq,
+                               int ht_enabled, int chan_offset, int chan_width,
+                               int cf1, int cf2);
 int hostapd_dfs_radar_detected(struct hostapd_iface *iface, int freq,
                               int ht_enabled,
                               int chan_offset, int chan_width,

diff --git a/src/ap/drv_callbacks.c b/src/ap/drv_callbacks.c
index f69c65529bd81a24eda298336d352494df928348..46b2d4c8a9ea84f52444ed59a67ed65029f80359 100644 (file)
--- a/src/ap/drv_callbacks.c
+++ b/src/ap/drv_callbacks.c
@@ -1121,6 +1121,16 @@ static void hostapd_event_dfs_radar_detected(struct hostapd_data *hapd,
 }
 
 
+static void hostapd_event_dfs_pre_cac_expired(struct hostapd_data *hapd,
+                                             struct dfs_event *radar)
+{
+       wpa_printf(MSG_DEBUG, "DFS Pre-CAC expired on %d MHz", radar->freq);
+       hostapd_dfs_pre_cac_expired(hapd->iface, radar->freq, radar->ht_enabled,
+                                   radar->chan_offset, radar->chan_width,
+                                   radar->cf1, radar->cf2);
+}
+
+
 static void hostapd_event_dfs_cac_finished(struct hostapd_data *hapd,
                                           struct dfs_event *radar)
 {
@@ -1313,6 +1323,11 @@ void wpa_supplicant_event(void *ctx, enum wpa_event_type event,
                        break;
                hostapd_event_dfs_radar_detected(hapd, &data->dfs_event);
                break;
+       case EVENT_DFS_PRE_CAC_EXPIRED:
+               if (!data)
+                       break;
+               hostapd_event_dfs_pre_cac_expired(hapd, &data->dfs_event);
+               break;
        case EVENT_DFS_CAC_FINISHED:
                if (!data)
                        break;

diff --git a/src/common/wpa_ctrl.h b/src/common/wpa_ctrl.h
index 4649eab95289aeb94a7d9eaab3319cd070d49dee..247bf80cb60a0fa9e2d5e875014905663decc01d 100644 (file)
--- a/src/common/wpa_ctrl.h
+++ b/src/common/wpa_ctrl.h
@@ -275,6 +275,7 @@ extern "C" {
 #define DFS_EVENT_CAC_START "DFS-CAC-START "
 #define DFS_EVENT_CAC_COMPLETED "DFS-CAC-COMPLETED "
 #define DFS_EVENT_NOP_FINISHED "DFS-NOP-FINISHED "
+#define DFS_EVENT_PRE_CAC_EXPIRED "DFS-PRE-CAC-EXPIRED "
 
 #define AP_CSA_FINISHED "AP-CSA-FINISHED "