[RFC] nl80211: allow Android P2P functionality

[Sreenath]

Hello Johannes,

Does this patch has to be applied on top of the patches submitted by 
David Spinadel or hostap default git checkout code?

Also whether wpa_supplicant has to be started on dummy 'p2p0' interface 
along with WLAN primary interface. Because with out that, control socket 
won't be created on 'p2p0' and which in turn is needed by Android 
framework for P2P operations.

Regards,
Sreenath

On 04/23/2013 06:17 PM, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg at intel.com>
>
> To support Android the kernel may have a "p2p0" netdev for a
> P2P-Device even though this isn't very useful, but Android
> requires a netdev. To support this in the supplicant, if the
> interface mode is P2P_DEVICE, re-set it to the same instead
> of STATION mode.
>
> Note that this is only possible with a kernel that creates a
> netdev for the P2P-Device wdev.
>
> Change-Id: Ia558cf847e0753b9c77056deee3acc618a63755f
> Signed-hostap: Johannes Berg <johannes.berg at intel.com>
> ---
>   src/drivers/driver_nl80211.c | 50 +++++++++++++++++++++++++++++++++++++++-----
>   1 file changed, 45 insertions(+), 5 deletions(-)
>
> diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
> index 3b0dba4..7b14219 100644
> --- a/src/drivers/driver_nl80211.c
> +++ b/src/drivers/driver_nl80211.c
> @@ -537,6 +537,7 @@ static void * nl80211_cmd(struct wpa_driver_nl80211_data *drv,
>   
>   struct wiphy_idx_data {
>   	int wiphy_idx;
> +	enum nl80211_iftype nlmode;
>   };
>   
>   
> @@ -552,6 +553,9 @@ static int netdev_info_handler(struct nl_msg *msg, void *arg)
>   	if (tb[NL80211_ATTR_WIPHY])
>   		info->wiphy_idx = nla_get_u32(tb[NL80211_ATTR_WIPHY]);
>   
> +	if (tb[NL80211_ATTR_IFTYPE])
> +		info->nlmode = nla_get_u32(tb[NL80211_ATTR_IFTYPE]);
> +
>   	return NL_SKIP;
>   }
>   
> @@ -580,6 +584,30 @@ nla_put_failure:
>   }
>   
>   
> +static enum nl80211_iftype nl80211_get_ifmode(struct i802_bss *bss)
> +{
> +	struct nl_msg *msg;
> +	struct wiphy_idx_data data = {
> +		.wiphy_idx = -1,
> +	};
> +
> +	msg = nlmsg_alloc();
> +	if (!msg)
> +		return -1;
> +
> +	nl80211_cmd(bss->drv, msg, 0, NL80211_CMD_GET_INTERFACE);
> +
> +	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, bss->ifindex);
> +
> +	if (send_and_recv_msgs(bss->drv, msg, netdev_info_handler, &data) == 0)
> +		return data.nlmode;
> +	msg = NULL;
> +nla_put_failure:
> +	nlmsg_free(msg);
> +	return NL80211_IFTYPE_UNSPECIFIED;
> +}
> +
> +
>   static int nl80211_register_beacons(struct wpa_driver_nl80211_data *drv,
>   				    struct nl80211_wiphy_data *w)
>   {
> @@ -3623,11 +3651,23 @@ wpa_driver_nl80211_finish_drv_init(struct wpa_driver_nl80211_data *drv)
>   	 * dynamically added interface (e.g., P2P) that was already configured
>   	 * with proper iftype.
>   	 */
> -	if (drv->ifindex != drv->global->if_add_ifindex &&
> -	    wpa_driver_nl80211_set_mode(bss, NL80211_IFTYPE_STATION) < 0) {
> -		wpa_printf(MSG_ERROR, "nl80211: Could not configure driver to "
> -			   "use managed mode");
> -		return -1;
> +	if (drv->ifindex != drv->global->if_add_ifindex) {
> +		enum nl80211_iftype nlmode;
> +
> +		nlmode = nl80211_get_ifmode(bss);
> +		if (nlmode != NL80211_IFTYPE_P2P_DEVICE)
> +			nlmode = NL80211_IFTYPE_STATION;
> +
> +		if (wpa_driver_nl80211_set_mode(bss, nlmode) < 0) {
> +			wpa_printf(MSG_ERROR, "nl80211: Could not configure "
> +				   "driver to use %s mode",
> +				   nlmode == NL80211_IFTYPE_STATION ?
> +					"managed" : "P2P-Device");
> +			return -1;
> +		}
> +
> +		/* always use managed mode internally, even for P2P-Device */
> +		drv->nlmode = NL80211_IFTYPE_STATION;
>   	}
>   
>   	if (linux_set_iface_flags(drv->global->ioctl_sock, bss->ifname, 1)) {