nl80211: Add means to query preferred channels

Extend the QCA vendor specific nl80211 interface to query the preferred
frequency list from driver and add a new wpa_cli command to query this
information.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

src/drivers/driver.h

@@ -1404,6 +1404,16 @@ enum wpa_driver_if_type {
 	 * WPA_IF_MESH - Mesh interface
 	 */
 	WPA_IF_MESH,
+
+	/*
+	 * WPA_IF_TDLS - TDLS offchannel interface (used for pref freq only)
+	 */
+	WPA_IF_TDLS,
+
+	/*
+	 * WPA_IF_IBSS - IBSS interface (used for pref freq only)
+	 */
+	WPA_IF_IBSS,
 };
 
 struct wpa_init_params {
@@ -3404,6 +3414,20 @@ struct wpa_driver_ops {
 	 */
 	int (*set_band)(void *priv, enum set_band band);
 
+	/**
+	 * get_pref_freq_list - Get preferred frequency list for an interface
+	 * @priv: Private driver interface data
+	 * @if_type: Interface type
+	 * @num: Number of channels
+	 * @freq_list: Preferred channel frequency list encoded in MHz values
+	 * Returns 0 on success, -1 on failure
+	 *
+	 * This command can be used to query the preferred frequency list from
+	 * the driver specific to a particular interface type.
+	 */
+	int (*get_pref_freq_list)(void *priv, enum wpa_driver_if_type if_type,
+				  unsigned int *num, unsigned int *freq_list);
+
 	/**
 	 * set_prob_oper_freq - Indicate probable P2P operating channel
 	 * @priv: Private driver interface data

src/drivers/driver_nl80211.c

@@ -5804,8 +5804,9 @@ static enum nl80211_iftype wpa_driver_nl80211_if_type(
 		return NL80211_IFTYPE_P2P_DEVICE;
 	case WPA_IF_MESH:
 		return NL80211_IFTYPE_MESH_POINT;
+	default:
+		return -1;
 	}
-	return -1;
 }
 
 
@@ -8509,6 +8510,147 @@ static int nl80211_set_band(void *priv, enum set_band band)
 }
 
 
+struct nl80211_pcl {
+	unsigned int num;
+	unsigned int *freq_list;
+};
+
+static int preferred_freq_info_handler(struct nl_msg *msg, void *arg)
+{
+	struct nlattr *tb[NL80211_ATTR_MAX + 1];
+	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+	struct nl80211_pcl *param = arg;
+	struct nlattr *nl_vend, *attr;
+	enum qca_iface_type iface_type;
+	struct nlattr *tb_vendor[QCA_WLAN_VENDOR_ATTR_MAX + 1];
+	unsigned int num, max_num;
+	u32 *freqs;
+
+	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
+		  genlmsg_attrlen(gnlh, 0), NULL);
+
+	nl_vend = tb[NL80211_ATTR_VENDOR_DATA];
+	if (!nl_vend)
+		return NL_SKIP;
+
+	nla_parse(tb_vendor, QCA_WLAN_VENDOR_ATTR_MAX,
+		  nla_data(nl_vend), nla_len(nl_vend), NULL);
+
+	attr = tb_vendor[
+		QCA_WLAN_VENDOR_ATTR_GET_PREFERRED_FREQ_LIST_IFACE_TYPE];
+	if (!attr) {
+		wpa_printf(MSG_ERROR, "nl80211: iface_type couldn't be found");
+		param->num = 0;
+		return NL_SKIP;
+	}
+
+	iface_type = (enum qca_iface_type) nla_get_u32(attr);
+	wpa_printf(MSG_DEBUG, "nl80211: Driver returned iface_type=%d",
+		   iface_type);
+
+	attr = tb_vendor[QCA_WLAN_VENDOR_ATTR_GET_PREFERRED_FREQ_LIST];
+	if (!attr) {
+		wpa_printf(MSG_ERROR,
+			   "nl80211: preferred_freq_list couldn't be found");
+		param->num = 0;
+		return NL_SKIP;
+	}
+
+	/*
+	 * param->num has the maximum number of entries for which there
+	 * is room in the freq_list provided by the caller.
+	 */
+	freqs = nla_data(attr);
+	max_num = nla_len(attr) / sizeof(u32);
+	if (max_num > param->num)
+		max_num = param->num;
+	for (num = 0; num < max_num; num++)
+		param->freq_list[num] = freqs[num];
+	param->num = num;
+
+	return NL_SKIP;
+}
+
+
+static int nl80211_get_pref_freq_list(void *priv,
+				      enum wpa_driver_if_type if_type,
+				      unsigned int *num,
+				      unsigned int *freq_list)
+{
+	struct i802_bss *bss = priv;
+	struct wpa_driver_nl80211_data *drv = bss->drv;
+	struct nl_msg *msg;
+	int ret;
+	unsigned int i;
+	struct nlattr *params;
+	struct nl80211_pcl param;
+	enum qca_iface_type iface_type;
+
+	if (!drv->get_pref_freq_list)
+		return -1;
+
+	switch (if_type) {
+	case WPA_IF_STATION:
+		iface_type = QCA_IFACE_TYPE_STA;
+		break;
+	case WPA_IF_AP_BSS:
+		iface_type = QCA_IFACE_TYPE_AP;
+		break;
+	case WPA_IF_P2P_GO:
+		iface_type = QCA_IFACE_TYPE_P2P_GO;
+		break;
+	case WPA_IF_P2P_CLIENT:
+		iface_type = QCA_IFACE_TYPE_P2P_CLIENT;
+		break;
+	case WPA_IF_IBSS:
+		iface_type = QCA_IFACE_TYPE_IBSS;
+		break;
+	case WPA_IF_TDLS:
+		iface_type = QCA_IFACE_TYPE_TDLS;
+		break;
+	default:
+		return -1;
+	}
+
+	param.num = *num;
+	param.freq_list = freq_list;
+
+	if (!(msg = nl80211_drv_msg(drv, 0, NL80211_CMD_VENDOR)) ||
+	    nla_put_u32(msg, NL80211_ATTR_IFINDEX, drv->ifindex) ||
+	    nla_put_u32(msg, NL80211_ATTR_VENDOR_ID, OUI_QCA) ||
+	    nla_put_u32(msg, NL80211_ATTR_VENDOR_SUBCMD,
+			QCA_NL80211_VENDOR_SUBCMD_GET_PREFERRED_FREQ_LIST) ||
+	    !(params = nla_nest_start(msg, NL80211_ATTR_VENDOR_DATA)) ||
+	    nla_put_u32(msg,
+			QCA_WLAN_VENDOR_ATTR_GET_PREFERRED_FREQ_LIST_IFACE_TYPE,
+			iface_type)) {
+		wpa_printf(MSG_ERROR,
+			   "%s: err in adding vendor_cmd and vendor_data",
+			   __func__);
+		nlmsg_free(msg);
+		return -1;
+	}
+	nla_nest_end(msg, params);
+
+	os_memset(freq_list, 0, *num * sizeof(freq_list[0]));
+	ret = send_and_recv_msgs(drv, msg, preferred_freq_info_handler, &param);
+	if (ret) {
+		wpa_printf(MSG_ERROR,
+			   "%s: err in send_and_recv_msgs", __func__);
+		return ret;
+	}
+
+	*num = param.num;
+
+	for (i = 0; i < *num; i++) {
+		wpa_printf(MSG_DEBUG, "nl80211: preferred_channel_list[%d]=%d",
+			   i, freq_list[i]);
+	}
+
+	return 0;
+}
+
+
 static int nl80211_set_prob_oper_freq(void *priv, unsigned int freq)
 {
 	struct i802_bss *bss = priv;
@@ -8663,5 +8805,6 @@ const struct wpa_driver_ops wpa_driver_nl80211_ops = {
 	.del_tx_ts = nl80211_del_ts,
 	.do_acs = wpa_driver_do_acs,
 	.set_band = nl80211_set_band,
+	.get_pref_freq_list = nl80211_get_pref_freq_list,
 	.set_prob_oper_freq = nl80211_set_prob_oper_freq,
 };

src/drivers/driver_nl80211.h

@@ -146,6 +146,7 @@ struct wpa_driver_nl80211_data {
 	unsigned int set_rekey_offload:1;
 	unsigned int p2p_go_ctwindow_supported:1;
 	unsigned int setband_vendor_cmd_avail:1;
+	unsigned int get_pref_freq_list:1;
 	unsigned int set_prob_oper_freq:1;
 
 	u64 remain_on_chan_cookie;

src/drivers/driver_nl80211_capa.c

@@ -589,6 +589,9 @@ static int wiphy_info_handler(struct nl_msg *msg, void *arg)
 				case QCA_NL80211_VENDOR_SUBCMD_GET_FEATURES:
 					drv->get_features_vendor_cmd_avail = 1;
 					break;
+				case QCA_NL80211_VENDOR_SUBCMD_GET_PREFERRED_FREQ_LIST:
+					drv->get_pref_freq_list = 1;
+					break;
 				case QCA_NL80211_VENDOR_SUBCMD_SET_PROBABLE_OPER_CHANNEL:
 					drv->set_prob_oper_freq = 1;
 					break;

wpa_supplicant/ctrl_iface.c

@@ -6654,6 +6654,53 @@ static int wpa_supplicant_signal_poll(struct wpa_supplicant *wpa_s, char *buf,
 }
 
 
+static int wpas_ctrl_iface_get_pref_freq_list(
+	struct wpa_supplicant *wpa_s, char *cmd, char *buf, size_t buflen)
+{
+	unsigned int freq_list[100], num = 100, i;
+	int ret;
+	enum wpa_driver_if_type iface_type;
+	char *pos, *end;
+
+	pos = buf;
+	end = buf + buflen;
+
+	/* buf: "<interface_type>" */
+	if (os_strcmp(cmd, "STATION") == 0)
+		iface_type = WPA_IF_STATION;
+	else if (os_strcmp(cmd, "AP") == 0)
+		iface_type = WPA_IF_AP_BSS;
+	else if (os_strcmp(cmd, "P2P_GO") == 0)
+		iface_type = WPA_IF_P2P_GO;
+	else if (os_strcmp(cmd, "P2P_CLIENT") == 0)
+		iface_type = WPA_IF_P2P_CLIENT;
+	else if (os_strcmp(cmd, "IBSS") == 0)
+		iface_type = WPA_IF_IBSS;
+	else if (os_strcmp(cmd, "TDLS") == 0)
+		iface_type = WPA_IF_TDLS;
+	else
+		return -1;
+
+	wpa_printf(MSG_DEBUG,
+		   "CTRL_IFACE: GET_PREF_FREQ_LIST iface_type=%d (%s)",
+		   iface_type, buf);
+
+	ret = wpa_drv_get_pref_freq_list(wpa_s, iface_type, &num, freq_list);
+	if (ret)
+		return -1;
+
+	for (i = 0; i < num; i++) {
+		ret = os_snprintf(pos, end - pos, "%s%u",
+				  i > 0 ? "," : "", freq_list[i]);
+		if (os_snprintf_error(end - pos, ret))
+			return -1;
+		pos += ret;
+	}
+
+	return pos - buf;
+}
+
+
 static int wpa_supplicant_pktcnt_poll(struct wpa_supplicant *wpa_s, char *buf,
 				      size_t buflen)
 {
@@ -8750,6 +8797,9 @@ char * wpa_supplicant_ctrl_iface_process(struct wpa_supplicant *wpa_s,
 	} else if (os_strncmp(buf, "MAC_RAND_SCAN ", 14) == 0) {
 		if (wpas_ctrl_iface_mac_rand_scan(wpa_s, buf + 14))
 			reply_len = -1;
+	} else if (os_strncmp(buf, "GET_PREF_FREQ_LIST ", 19) == 0) {
+		reply_len = wpas_ctrl_iface_get_pref_freq_list(
+			wpa_s, buf + 19, reply, reply_size);
 	} else {
 		os_memcpy(reply, "UNKNOWN COMMAND\n", 16);
 		reply_len = 16;

wpa_supplicant/driver_i.h

@@ -893,6 +893,17 @@ static inline int wpa_drv_setband(struct wpa_supplicant *wpa_s,
 	return wpa_s->driver->set_band(wpa_s->drv_priv, band);
 }
 
+static inline int wpa_drv_get_pref_freq_list(struct wpa_supplicant *wpa_s,
+					     enum wpa_driver_if_type if_type,
+					     unsigned int *num,
+					     unsigned int *freq_list)
+{
+	if (!wpa_s->driver->get_pref_freq_list)
+		return 0;
+	return wpa_s->driver->get_pref_freq_list(wpa_s->drv_priv, if_type,
+						 num, freq_list);
+}
+
 static inline int wpa_drv_set_prob_oper_freq(struct wpa_supplicant *wpa_s,
 					     unsigned int freq)
 {

wpa_supplicant/wpa_cli.c

@@ -2801,6 +2801,13 @@ static int wpa_cli_cmd_mac_rand_scan(struct wpa_ctrl *ctrl, int argc,
 }
 
 
+static int wpa_cli_cmd_get_pref_freq_list(struct wpa_ctrl *ctrl, int argc,
+					  char *argv[])
+{
+	return wpa_cli_cmd(ctrl, "GET_PREF_FREQ_LIST", 1, argc, argv);
+}
+
+
 enum wpa_cli_cmd_flags {
 	cli_cmd_flag_none		= 0x00,
 	cli_cmd_flag_sensitive		= 0x01
@@ -3355,6 +3362,9 @@ static const struct wpa_cli_cmd wpa_cli_commands[] = {
 	  "<scan|sched|pno|all> enable=<0/1> [addr=mac-address "
 	  "mask=mac-address-mask] = scan MAC randomization"
 	},
+	{ "get_pref_freq_list", wpa_cli_cmd_get_pref_freq_list, NULL,
+	  cli_cmd_flag_none,
+	  "<interface type> = retrieve preferred freq list for the specified interface type" },
 	{ NULL, NULL, NULL, cli_cmd_flag_none, NULL }
 };