mac80211: adding 802.11n IEs handling

This patch presents the ability to parse and compose HT IEs, and to put
the IE relevant data inside the mac80211's internal HT structures

Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: Ron Rindjunsky

net/mac80211/ieee80211_i.h

@@ -89,6 +89,8 @@ struct ieee80211_sta_bss {
 	size_t rsn_ie_len;
 	u8 *wmm_ie;
 	size_t wmm_ie_len;
+	u8 *ht_ie;
+	size_t ht_ie_len;
 #define IEEE80211_MAX_SUPP_RATES 32
 	u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
 	size_t supp_rates_len;
@@ -759,7 +761,11 @@ int ieee80211_sta_deauthenticate(struct net_device *dev, u16 reason);
 int ieee80211_sta_disassociate(struct net_device *dev, u16 reason);
 void ieee80211_erp_info_change_notify(struct net_device *dev, u8 changes);
 void ieee80211_reset_erp_info(struct net_device *dev);
-
+int ieee80211_ht_cap_ie_to_ht_info(struct ieee80211_ht_cap *ht_cap_ie,
+				   struct ieee80211_ht_info *ht_info);
+int ieee80211_ht_addt_info_ie_to_ht_bss_info(
+			struct ieee80211_ht_addt_info *ht_add_info_ie,
+			struct ieee80211_ht_bss_info *bss_info);
 /* ieee80211_iface.c */
 int ieee80211_if_add(struct net_device *dev, const char *name,
 		     struct net_device **new_dev, int type);

net/mac80211/ieee80211_sta.c

@@ -90,7 +90,8 @@ struct ieee802_11_elems {
 	u8 *ext_supp_rates;
 	u8 *wmm_info;
 	u8 *wmm_param;
-
+	u8 *ht_cap_elem;
+	u8 *ht_info_elem;
 	/* length of them, respectively */
 	u8 ssid_len;
 	u8 supp_rates_len;
@@ -106,6 +107,8 @@ struct ieee802_11_elems {
 	u8 ext_supp_rates_len;
 	u8 wmm_info_len;
 	u8 wmm_param_len;
+	u8 ht_cap_elem_len;
+	u8 ht_info_elem_len;
 };
 
 static void ieee802_11_parse_elems(u8 *start, size_t len,
@@ -190,6 +193,14 @@ static void ieee802_11_parse_elems(u8 *start, size_t len,
 			elems->ext_supp_rates = pos;
 			elems->ext_supp_rates_len = elen;
 			break;
+		case WLAN_EID_HT_CAPABILITY:
+			elems->ht_cap_elem = pos;
+			elems->ht_cap_elem_len = elen;
+			break;
+		case WLAN_EID_HT_EXTRA_INFO:
+			elems->ht_info_elem = pos;
+			elems->ht_info_elem_len = elen;
+			break;
 		default:
 			break;
 		}
@@ -332,6 +343,51 @@ static void ieee80211_handle_erp_ie(struct net_device *dev, u8 erp_value)
 		ieee80211_erp_info_change_notify(dev, changes);
 }
 
+int ieee80211_ht_cap_ie_to_ht_info(struct ieee80211_ht_cap *ht_cap_ie,
+				   struct ieee80211_ht_info *ht_info)
+{
+
+	if (ht_info == NULL)
+		return -EINVAL;
+
+	memset(ht_info, 0, sizeof(*ht_info));
+
+	if (ht_cap_ie) {
+		u8 ampdu_info = ht_cap_ie->ampdu_params_info;
+
+		ht_info->ht_supported = 1;
+		ht_info->cap = le16_to_cpu(ht_cap_ie->cap_info);
+		ht_info->ampdu_factor =
+			ampdu_info & IEEE80211_HT_CAP_AMPDU_FACTOR;
+		ht_info->ampdu_density =
+			(ampdu_info & IEEE80211_HT_CAP_AMPDU_DENSITY) >> 2;
+		memcpy(ht_info->supp_mcs_set, ht_cap_ie->supp_mcs_set, 16);
+	} else
+		ht_info->ht_supported = 0;
+
+	return 0;
+}
+
+int ieee80211_ht_addt_info_ie_to_ht_bss_info(
+			struct ieee80211_ht_addt_info *ht_add_info_ie,
+			struct ieee80211_ht_bss_info *bss_info)
+{
+	if (bss_info == NULL)
+		return -EINVAL;
+
+	memset(bss_info, 0, sizeof(*bss_info));
+
+	if (ht_add_info_ie) {
+		u16 op_mode;
+		op_mode = le16_to_cpu(ht_add_info_ie->operation_mode);
+
+		bss_info->primary_channel = ht_add_info_ie->control_chan;
+		bss_info->bss_cap = ht_add_info_ie->ht_param;
+		bss_info->bss_op_mode = (u8)(op_mode & 0xff);
+	}
+
+	return 0;
+}
 
 static void ieee80211_sta_send_associnfo(struct net_device *dev,
 					 struct ieee80211_if_sta *ifsta)
@@ -630,6 +686,19 @@ static void ieee80211_send_assoc(struct net_device *dev,
 		*pos++ = 1; /* WME ver */
 		*pos++ = 0;
 	}
+	/* wmm support is a must to HT */
+	if (wmm && mode->ht_info.ht_supported) {
+		__le16 tmp = cpu_to_le16(mode->ht_info.cap);
+		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap)+2);
+		*pos++ = WLAN_EID_HT_CAPABILITY;
+		*pos++ = sizeof(struct ieee80211_ht_cap);
+		memset(pos, 0, sizeof(struct ieee80211_ht_cap));
+		memcpy(pos, &tmp, sizeof(u16));
+		pos += sizeof(u16);
+		*pos++ = (mode->ht_info.ampdu_factor |
+				(mode->ht_info.ampdu_density << 2));
+		memcpy(pos, mode->ht_info.supp_mcs_set, 16);
+	}
 
 	kfree(ifsta->assocreq_ies);
 	ifsta->assocreq_ies_len = (skb->data + skb->len) - ies;
@@ -1380,6 +1449,7 @@ static void ieee80211_rx_bss_free(struct ieee80211_sta_bss *bss)
 	kfree(bss->wpa_ie);
 	kfree(bss->rsn_ie);
 	kfree(bss->wmm_ie);
+	kfree(bss->ht_ie);
 	kfree(bss);
 }
 
@@ -1637,7 +1707,22 @@ static void ieee80211_rx_bss_info(struct net_device *dev,
 		bss->wmm_ie = NULL;
 		bss->wmm_ie_len = 0;
 	}
-
+	if (elems.ht_cap_elem &&
+	    (!bss->ht_ie || bss->ht_ie_len != elems.ht_cap_elem_len ||
+	     memcmp(bss->ht_ie, elems.ht_cap_elem, elems.ht_cap_elem_len))) {
+		kfree(bss->ht_ie);
+		bss->ht_ie = kmalloc(elems.ht_cap_elem_len + 2, GFP_ATOMIC);
+		if (bss->ht_ie) {
+			memcpy(bss->ht_ie, elems.ht_cap_elem - 2,
+			       elems.ht_cap_elem_len + 2);
+			bss->ht_ie_len = elems.ht_cap_elem_len + 2;
+		} else
+			bss->ht_ie_len = 0;
+	} else if (!elems.ht_cap_elem && bss->ht_ie) {
+		kfree(bss->ht_ie);
+		bss->ht_ie = NULL;
+		bss->ht_ie_len = 0;
+	}
 
 	bss->hw_mode = rx_status->phymode;
 	bss->freq = rx_status->freq;