When an HT IBSS is configured, we add HT Information and HT Capabilities
IE to beacons & probe responses. This is done according to channel_type
transmitted by iw/cfg80211.
v2: Added helpers to build HT Capability & HT Information IE
Signed-off-by: Benoit Papillault <benoit.papillault@xxxxxxx>
---
net/mac80211/ibss.c | 64 +++++++++++++++++++++++++---
net/mac80211/ieee80211_i.h | 10 ++++
net/mac80211/util.c | 98 ++++++++++++++++++++++++++++++++++---------
3 files changed, 144 insertions(+), 28 deletions(-)
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index b72ee64..2371d69 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -64,6 +64,7 @@ static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const int beacon_int,
struct ieee80211_channel *chan,
+ enum nl80211_channel_type channel_type,
const u32 basic_rates,
const u16 capability, u64 tsf)
{
@@ -103,7 +104,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
local->oper_channel = chan;
- local->oper_channel_type = NL80211_CHAN_NO_HT;
+ local->oper_channel_type = channel_type;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
sband = local->hw.wiphy->bands[chan->band];
@@ -118,7 +119,10 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
*pos++ = basic | (u8) (rate / 5);
}
- /* Build IBSS probe response */
+ /*
+ * Build IBSS probe response template (this template is also used
+ * when sending beacon, see ieee80211_beacon_get_tim())
+ */
mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
@@ -165,6 +169,14 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
memcpy(pos, &supp_rates[8], rates);
}
+ if (channel_type != NL80211_CHAN_NO_HT &&
+ sband->ht_cap.ht_supported) {
+ pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
+ ieee80211_add_ht_cap(&pos, sband);
+ pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_info));
+ ieee80211_add_ht_info(&pos, sband, chan, channel_type);
+ }
+
if (ifibss->ie_len)
memcpy(skb_put(skb, ifibss->ie_len),
ifibss->ie, ifibss->ie_len);
@@ -202,6 +214,9 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
u32 basic_rates;
int i, j;
u16 beacon_int = cbss->beacon_interval;
+ const u8 * ht_info_ie;
+ const struct ieee80211_ht_info *ht_info;
+ enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT;
if (beacon_int < 10)
beacon_int = 10;
@@ -223,9 +238,28 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
}
}
+ /* parse HT Information IE, if present */
+ ht_info_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_INFORMATION);
+ if (ht_info_ie) {
+ ht_info = (const struct ieee80211_ht_info *)(ht_info_ie + 2);
+ switch (ht_info->ht_param
+ & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
+ case IEEE80211_HT_PARAM_CHA_SEC_NONE:
+ channel_type = NL80211_CHAN_HT20;
+ break;
+ case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
+ channel_type = NL80211_CHAN_HT40PLUS;
+ break;
+ case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
+ channel_type = NL80211_CHAN_HT40MINUS;
+ break;
+ }
+ }
+
__ieee80211_sta_join_ibss(sdata, cbss->bssid,
beacon_int,
cbss->channel,
+ channel_type,
basic_rates,
cbss->capability,
cbss->tsf);
@@ -529,7 +563,8 @@ static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
sdata->drop_unencrypted = 0;
__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
- ifibss->channel, 3, /* first two are basic */
+ ifibss->channel, ifibss->channel_type,
+ 3, /* first two are basic */
capability, 0);
}
@@ -906,6 +941,7 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
sdata->vif.bss_conf.beacon_int = params->beacon_interval;
sdata->u.ibss.channel = params->channel;
+ sdata->u.ibss.channel_type = params->channel_type;
sdata->u.ibss.fixed_channel = params->channel_fixed;
/* fix ourselves to that channel now already */
@@ -921,11 +957,25 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
sdata->u.ibss.ie_len = params->ie_len;
}
+ /*
+ * Allocate IBSS probe response template (see
+ * __ieee80211_sta_join_ibss for the needed size). According to IEEE
+ * 802.11-2007 10.4.4.2, there is only 20 possibles values. We
+ * support up IEEE80211_MAX_SUPP_RATES (currently 32) : so 8 for
+ * Supported Rates and IEEE80211_MAX_SUPP_RATES-8 for Extended
+ * Supported Rates
+ */
+
skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
- 36 /* bitrates */ +
- 34 /* SSID */ +
- 3 /* DS params */ +
- 4 /* IBSS params */ +
+ sizeof(struct ieee80211_hdr_3addr) +
+ 12 /* struct ieee80211_mgmt.u.beacon */ +
+ 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
+ 2 + 8 /* max Supported Rates */ +
+ 3 /* max DS params */ +
+ 4 /* IBSS params */ +
+ 2 + (IEEE80211_MAX_SUPP_RATES-8) /* max Ext Rates */ +
+ 2 + sizeof(struct ieee80211_ht_cap) +
+ 2 + sizeof(struct ieee80211_ht_info) +
params->ie_len);
if (!skb)
return -ENOMEM;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index c8077a3..b3a5d3c 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -404,6 +404,7 @@ struct ieee80211_if_ibss {
u8 ssid_len, ie_len;
u8 *ie;
struct ieee80211_channel *channel;
+ enum nl80211_channel_type channel_type;
unsigned long ibss_join_req;
/* probe response/beacon for IBSS */
@@ -1193,6 +1194,15 @@ void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
u16 transaction, u16 auth_alg,
u8 *extra, size_t extra_len, const u8 *bssid,
const u8 *key, u8 key_len, u8 key_idx);
+
+int ieee80211_add_ht_cap(u8 **ppos,
+ struct ieee80211_supported_band *sband);
+
+int ieee80211_add_ht_info(u8 **ppos,
+ struct ieee80211_supported_band *sband,
+ struct ieee80211_channel *channel,
+ enum nl80211_channel_type channel_type);
+
int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
const u8 *ie, size_t ie_len,
enum ieee80211_band band);
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 2b75b4f..cc08411 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -898,6 +898,82 @@ void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
ieee80211_tx_skb(sdata, skb);
}
+int ieee80211_add_ht_cap(u8 **ppos,
+ struct ieee80211_supported_band *sband)
+{
+ u16 cap = sband->ht_cap.cap;
+ struct ieee80211_ht_cap ht_cap;
+ u8 *pos = *ppos;
+
+ if (ieee80211_disable_40mhz_24ghz &&
+ sband->band == IEEE80211_BAND_2GHZ) {
+ cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
+ cap &= ~IEEE80211_HT_CAP_SGI_40;
+ }
+
+ ht_cap.cap_info = cpu_to_le16(cap);
+ ht_cap.ampdu_params_info = sband->ht_cap.ampdu_factor |
+ (sband->ht_cap.ampdu_density <<
+ IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
+ ht_cap.mcs = sband->ht_cap.mcs;
+ ht_cap.extended_ht_cap_info = cpu_to_le16(0);
+ ht_cap.tx_BF_cap_info = cpu_to_le32(0);
+ ht_cap.antenna_selection_info = 0;
+
+ /* HT Capabilities element */
+ *pos++ = WLAN_EID_HT_CAPABILITY;
+ *pos++ = sizeof(struct ieee80211_ht_cap);
+ memcpy(pos, &ht_cap, sizeof(struct ieee80211_ht_cap));
+ pos += sizeof(struct ieee80211_ht_cap);
+
+ *ppos = pos;
+
+ return 1;
+}
+
+int ieee80211_add_ht_info(u8 **ppos,
+ struct ieee80211_supported_band *sband,
+ struct ieee80211_channel *channel,
+ enum nl80211_channel_type channel_type)
+{
+ struct ieee80211_ht_info ht_info;
+ u8 *pos = *ppos;
+
+ ht_info.control_chan =
+ ieee80211_frequency_to_channel(channel->center_freq);
+ ht_info.ht_param = 0;
+ switch (channel_type) {
+ case NL80211_CHAN_NO_HT: /* to make compiler happy */
+ case NL80211_CHAN_HT20:
+ ht_info.ht_param |= IEEE80211_HT_PARAM_CHA_SEC_NONE;
+ break;
+ case NL80211_CHAN_HT40MINUS:
+ ht_info.ht_param |= IEEE80211_HT_PARAM_CHA_SEC_BELOW;
+ break;
+ case NL80211_CHAN_HT40PLUS:
+ ht_info.ht_param |= IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
+ break;
+ }
+ if (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40)
+ ht_info.ht_param |= IEEE80211_HT_PARAM_CHAN_WIDTH_ANY;
+ ht_info.operation_mode = cpu_to_le16(0);
+ ht_info.stbc_param = cpu_to_le16(0);
+ /* It seems that Basic MCS set and Supported MCS set are identical
+ * for the first 10 bytes */
+ memset(&ht_info.basic_set, 0, 16);
+ memcpy(&ht_info.basic_set, &sband->ht_cap.mcs, 10);
+
+ /* HT Information element */
+ *pos++ = WLAN_EID_HT_INFORMATION;
+ *pos++ = sizeof(struct ieee80211_ht_info);
+ memcpy(pos, &ht_info, sizeof(struct ieee80211_ht_info));
+ pos += sizeof(struct ieee80211_ht_info);
+
+ *ppos = pos;
+
+ return 1;
+}
+
int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
const u8 *ie, size_t ie_len,
enum ieee80211_band band)
@@ -966,27 +1042,7 @@ int ieee80211_build_preq_ies(struct ieee80211_local *local, u8 *buffer,
}
if (sband->ht_cap.ht_supported) {
- u16 cap = sband->ht_cap.cap;
- __le16 tmp;
-
- if (ieee80211_disable_40mhz_24ghz &&
- sband->band == IEEE80211_BAND_2GHZ) {
- cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
- cap &= ~IEEE80211_HT_CAP_SGI_40;
- }
-
- *pos++ = WLAN_EID_HT_CAPABILITY;
- *pos++ = sizeof(struct ieee80211_ht_cap);
- memset(pos, 0, sizeof(struct ieee80211_ht_cap));
- tmp = cpu_to_le16(cap);
- memcpy(pos, &tmp, sizeof(u16));
- pos += sizeof(u16);
- *pos++ = sband->ht_cap.ampdu_factor |
- (sband->ht_cap.ampdu_density <<
- IEEE80211_HT_AMPDU_PARM_DENSITY_SHIFT);
- memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
- pos += sizeof(sband->ht_cap.mcs);
- pos += 2 + 4 + 1; /* ext info, BF cap, antsel */
+ ieee80211_add_ht_cap(&pos, sband);
}
/*
--
1.5.6.5
--
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