staging: wilc1000: refactor wilc_parse_network_info() using kernel framework api's

Refactor wilc_parse_network_info() by making use of cfg80211.h provided
API.
Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wilc1000/coreconfigurator.c

@@ -4,7 +4,7 @@
  * All rights reserved.
  */
 
-#include <linux/ieee80211.h>
+#include <net/cfg80211.h>
 
 #include "coreconfigurator.h"
 
@@ -116,11 +116,11 @@ static inline void get_address3(u8 *msa, u8 *addr)
 	memcpy(addr, msa + 16, 6);
 }
 
-static inline void get_bssid(u8 *data, u8 *bssid)
+static inline void get_bssid(__le16 fc, u8 *data, u8 *bssid)
 {
-	if (get_from_ds(data) == 1)
+	if (ieee80211_has_fromds(fc))
 		get_address2(data, bssid);
-	else if (get_to_ds(data) == 1)
+	else if (ieee80211_has_tods(fc))
 		get_address1(data, bssid);
 	else
 		get_address3(data, bssid);
@@ -202,17 +202,18 @@ s32 wilc_parse_network_info(u8 *msg_buffer,
 			    struct network_info **ret_network_info)
 {
 	struct network_info *network_info;
-	u8 *wid_val, *msa, *tim_elm, *ies;
-	u32 tsf_lo, tsf_hi;
+	struct ieee80211_mgmt *mgt;
+	u8 *wid_val, *msa, *ies;
 	u16 wid_len, rx_len, ies_len;
-	u8 msg_type, index;
+	u8 msg_type;
+	size_t offset;
+	const u8 *ch_elm, *tim_elm, *ssid_elm;
 
 	msg_type = msg_buffer[0];
-
 	if ('N' != msg_type)
 		return -EFAULT;
 
-	wid_len = MAKE_WORD16(msg_buffer[6], msg_buffer[7]);
+	wid_len = get_unaligned_le16(&msg_buffer[6]);
 	wid_val = &msg_buffer[8];
 
 	network_info = kzalloc(sizeof(*network_info), GFP_KERNEL);
@@ -222,43 +223,62 @@ s32 wilc_parse_network_info(u8 *msg_buffer,
 	network_info->rssi = wid_val[0];
 
 	msa = &wid_val[1];
-
+	mgt = (struct ieee80211_mgmt *)&wid_val[1];
 	rx_len = wid_len - 1;
-	network_info->cap_info = get_cap_info(msa);
-	network_info->tsf_lo = get_beacon_timestamp_lo(msa);
-
-	tsf_lo = get_beacon_timestamp_lo(msa);
-	tsf_hi = get_beacon_timestamp_hi(msa);
-
-	network_info->tsf_hi = tsf_lo | ((u64)tsf_hi << 32);
-
-	get_ssid(msa, network_info->ssid, &network_info->ssid_len);
-	get_bssid(msa, network_info->bssid);
 
-	network_info->ch = get_current_channel_802_11n(msa, rx_len
-						       + FCS_LEN);
-
-	index = MAC_HDR_LEN + TIME_STAMP_LEN;
-
-	network_info->beacon_period = get_beacon_period(msa + index);
+	if (ieee80211_is_probe_resp(mgt->frame_control)) {
+		network_info->cap_info = le16_to_cpu(mgt->u.probe_resp.capab_info);
+		network_info->beacon_period = le16_to_cpu(mgt->u.probe_resp.beacon_int);
+		network_info->tsf_hi = le64_to_cpu(mgt->u.probe_resp.timestamp);
+		network_info->tsf_lo = (u32)network_info->tsf_hi;
+		offset = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
+	} else if (ieee80211_is_beacon(mgt->frame_control)) {
+		network_info->cap_info = le16_to_cpu(mgt->u.beacon.capab_info);
+		network_info->beacon_period = le16_to_cpu(mgt->u.beacon.beacon_int);
+		network_info->tsf_hi = le64_to_cpu(mgt->u.beacon.timestamp);
+		network_info->tsf_lo = (u32)network_info->tsf_hi;
+		offset = offsetof(struct ieee80211_mgmt, u.beacon.variable);
+	} else {
+		/* only process probe response and beacon frame */
+		kfree(network_info);
+		return -EIO;
+	}
 
-	index += BEACON_INTERVAL_LEN + CAP_INFO_LEN;
+	get_bssid(mgt->frame_control, msa, network_info->bssid);
 
-	tim_elm = get_tim_elm(msa, rx_len + FCS_LEN, index);
-	if (tim_elm)
-		network_info->dtim_period = tim_elm[3];
-	ies = &msa[TAG_PARAM_OFFSET];
-	ies_len = rx_len - TAG_PARAM_OFFSET;
+	ies = mgt->u.beacon.variable;
+	ies_len = rx_len - offset;
+	if (ies_len <= 0) {
+		kfree(network_info);
+		return -EIO;
+	}
 
-	if (ies_len > 0) {
 	network_info->ies = kmemdup(ies, ies_len, GFP_KERNEL);
 	if (!network_info->ies) {
 		kfree(network_info);
 		return -ENOMEM;
 	}
-	}
+
 	network_info->ies_len = ies_len;
 
+	ssid_elm = cfg80211_find_ie(WLAN_EID_SSID, ies, ies_len);
+	if (ssid_elm) {
+		network_info->ssid_len = ssid_elm[1];
+		if (network_info->ssid_len <= IEEE80211_MAX_SSID_LEN)
+			memcpy(network_info->ssid, ssid_elm + 2,
+			       network_info->ssid_len);
+		else
+			network_info->ssid_len = 0;
+	}
+
+	ch_elm = cfg80211_find_ie(WLAN_EID_DS_PARAMS, ies, ies_len);
+	if (ch_elm && ch_elm[1] > 0)
+		network_info->ch = ch_elm[2];
+
+	tim_elm = cfg80211_find_ie(WLAN_EID_TIM, ies, ies_len);
+	if (tim_elm && tim_elm[1] >= 2)
+		network_info->dtim_period = tim_elm[3];
+
 	*ret_network_info = network_info;
 
 	return 0;