[PATCH 09/14] wpa_supplicant: Implement P2P_GO_FREQ_MOVE_SCM_ECSA policy

[Ilan Peer]

From: Andrei Otcheretianski <andrei.otcheretianski at intel.com>

Add new GO frequency move policy. The P2P_GO_FREQ_MOVE_SCM_ECSA prefers SCM
if all the clients advertise eCSA support and the candidate frequency is one
of the group common frequencies.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski at intel.com>
---
 src/ap/ieee802_11.c             |    3 +++
 src/ap/sta_info.h               |    1 +
 wpa_supplicant/config.h         |    7 ++++++-
 wpa_supplicant/p2p_supplicant.c |   29 +++++++++++++++++++++++++++++
 4 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/src/ap/ieee802_11.c b/src/ap/ieee802_11.c
index 3ddb1ee..41b56c8 100644
--- a/src/ap/ieee802_11.c
+++ b/src/ap/ieee802_11.c
@@ -868,6 +868,9 @@ static u16 check_ext_capab(struct hostapd_data *hapd, struct sta_info *sta,
 	}
 #endif /* CONFIG_INTERWORKING */
 
+	if (ext_capab_ie_len > 0)
+		sta->ecsa_supported = !!(ext_capab_ie[0] & BIT(2));
+
 	return WLAN_STATUS_SUCCESS;
 }
 
diff --git a/src/ap/sta_info.h b/src/ap/sta_info.h
index 03db98f..6a7a69a 100644
--- a/src/ap/sta_info.h
+++ b/src/ap/sta_info.h
@@ -60,6 +60,7 @@ struct sta_info {
 	unsigned int qos_map_enabled:1;
 	unsigned int remediation:1;
 	unsigned int hs20_deauth_requested:1;
+	unsigned int ecsa_supported:1;
 
 	u16 auth_alg;
 
diff --git a/wpa_supplicant/config.h b/wpa_supplicant/config.h
index ed07cca..771b2ed 100644
--- a/wpa_supplicant/config.h
+++ b/wpa_supplicant/config.h
@@ -734,12 +734,17 @@ struct wpa_config {
 	 * frequency list of the local device and the peer device.
 	 *
 	 * @P2P_GO_FREQ_MOVE_STAY: prefer to stay on the current frequency.
+	 *
+	 * @P2P_GO_FREQ_MOVE_SCM_ECSA: same as
+	 * P2P_GO_FREQ_MOVE_SCM_PEER_SUPPORTS but a transition is possible only
+	 * if all peers advertise eCSA support.
 	 */
 	enum {
 		P2P_GO_FREQ_MOVE_SCM = 0,
 		P2P_GO_FREQ_MOVE_SCM_PEER_SUPPORTS = 1,
 		P2P_GO_FREQ_MOVE_STAY = 2,
-		P2P_GO_FREQ_MOVE_MAX = P2P_GO_FREQ_MOVE_STAY,
+		P2P_GO_FREQ_MOVE_SCM_ECSA = 3,
+		P2P_GO_FREQ_MOVE_MAX = P2P_GO_FREQ_MOVE_SCM_ECSA,
 
 	} p2p_go_freq_change_policy;
 
diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
index 22ba344..ab328f4 100644
--- a/wpa_supplicant/p2p_supplicant.c
+++ b/wpa_supplicant/p2p_supplicant.c
@@ -3029,6 +3029,29 @@ static int wpas_p2p_go_is_peer_freq(struct wpa_supplicant *wpa_s, int freq)
 }
 
 
+static int wpas_sta_check_ecsa(struct hostapd_data *hapd,
+			       struct sta_info *sta, void *ctx)
+{
+	int *ecsa_support = ctx;
+
+	*ecsa_support &= sta->ecsa_supported;
+
+	return 0;
+}
+
+/*
+ * Check if all the peers support eCSA
+ */
+static int wpas_p2p_go_peers_support_ecsa(struct wpa_supplicant *wpa_s)
+{
+	int ecsa_support = 1;
+
+	ap_for_each_sta(wpa_s->ap_iface->bss[0], wpas_sta_check_ecsa,
+			&ecsa_support);
+
+	return ecsa_support;
+}
+
 static int wpas_freq_included(struct wpa_supplicant *wpa_s,
 			      const struct p2p_channels *channels,
 			      unsigned int freq)
@@ -8365,6 +8388,12 @@ static void wpas_p2p_consider_moving_one_go(struct wpa_supplicant *wpa_s,
 			    P2P_GO_FREQ_MOVE_SCM_PEER_SUPPORTS) &&
 			   wpas_p2p_go_is_peer_freq(wpa_s, freqs[i].freq)) {
 			policy_move = 1;
+		} else if ((wpa_s->conf->p2p_go_freq_change_policy ==
+			    P2P_GO_FREQ_MOVE_SCM_ECSA) &&
+			   wpa_s->csa_supported &&
+			   wpas_p2p_go_is_peer_freq(wpa_s, freqs[i].freq) &&
+			   wpas_p2p_go_peers_support_ecsa(wpa_s)) {
+			policy_move = 1;
 		}
 	}
 
-- 
1.7.10.4