[PATCH 3/3] P2P: Optimize scan frequencies list when re-joining a persistent group

[Jouni Malinen]

On Mon, Mar 16, 2015 at 01:20:03AM -0400, Ilan Peer wrote:
> When starting a P2P client to re-join a persistent group
> (P2P_GROUP_ADD persistent=<id>), it is possible that the P2P GO was
> already found in previous scans. Try to get the P2P GO operating
> frequency from the scan results list so wpa_supplicant will initially
> scan only the P2P GO known operating frequency.

> diff --git a/wpa_supplicant/p2p_supplicant.c b/wpa_supplicant/p2p_supplicant.c
> @@ -5504,18 +5504,26 @@ int wpas_p2p_group_add_persistent(struct wpa_supplicant *wpa_s,
> -	} else {
> -		freq = neg_freq;
> -		if (freq < 0 ||
> -		    (freq > 0 && !freq_included(channels, freq)))
> -			freq = 0;
> -	}
> +	} else if (ssid->mode == WPAS_MODE_INFRA) {
> +		freq = wpas_p2p_select_go_freq(wpa_s, neg_freq);

That looks suspicious.. wpas_p2p_select_go_freq() is used only on the GO
device, so this cannot really be correct.

> +		if (freq <= 0 ||
> +		    (freq > 0 && !freq_included(channels, freq))) {
> +			struct os_reltime now;
> +			struct wpa_bss *bss =
> +				wpa_bss_get_p2p_dev_addr(wpa_s, ssid->bssid);
> +
> +			os_get_reltime(&now);
> +			if (bss &&
> +			    !os_reltime_expired(&now, &bss->last_update, 5))
> +				freq = bss->freq;
> +			else
> +				freq = 0;
> +		}

And the freq > 0 && !freq_included(channels, freq) case should clear
freq to 0 to match the current behavior.

-- 
Jouni Malinen                                            PGP id EFC895FA