nl80211: New command for adding extra IE(s) into management frames

A new nl80211 command, NL80211_CMD_SET_MGMT_EXTRA_IE, can be used to
add arbitrary IE data into the end of management frames. The interface
allows extra IEs to be configured for each management frame subtype, but
only some of them (ProbeReq, ProbeResp, Auth, (Re)AssocReq, Deauth,
Disassoc) are currently accepted in mac80211 implementation.

This makes it easier to implement IEEE 802.11 extensions like WPS and
FT that add IE(s) into some management frames. In addition, this can
be useful for testing and experimentation purposes.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 46 insertions, 6 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index f0d42498c25..43da6227b37 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -131,6 +131,12 @@ u64 ieee80211_sta_get_rates(struct ieee80211_local *local,
 
 /* frame sending functions */
 
+static void add_extra_ies(struct sk_buff *skb, u8 *ies, size_t ies_len)
+{
+	if (ies)
+		memcpy(skb_put(skb, ies_len), ies, ies_len);
+}
+
 /* also used by scanning code */
 void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
 			      u8 *ssid, size_t ssid_len)
@@ -142,7 +148,8 @@ void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
 	u8 *pos, *supp_rates, *esupp_rates = NULL;
 	int i;
 
-	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 200);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) + 200 +
+			    sdata->u.sta.ie_probereq_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
 		       "request\n", sdata->dev->name);
@@ -189,6 +196,9 @@ void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
 		*pos = rate->bitrate / 5;
 	}
 
+	add_extra_ies(skb, sdata->u.sta.ie_probereq,
+		      sdata->u.sta.ie_probereq_len);
+
 	ieee80211_tx_skb(sdata, skb, 0);
 }
 
@@ -202,7 +212,8 @@ static void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_mgmt *mgmt;
 
 	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
-			    sizeof(*mgmt) + 6 + extra_len);
+			    sizeof(*mgmt) + 6 + extra_len +
+			    sdata->u.sta.ie_auth_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for auth "
 		       "frame\n", sdata->dev->name);
@@ -225,6 +236,7 @@ static void ieee80211_send_auth(struct ieee80211_sub_if_data *sdata,
 	mgmt->u.auth.status_code = cpu_to_le16(0);
 	if (extra)
 		memcpy(skb_put(skb, extra_len), extra, extra_len);
+	add_extra_ies(skb, sdata->u.sta.ie_auth, sdata->u.sta.ie_auth_len);
 
 	ieee80211_tx_skb(sdata, skb, encrypt);
 }
@@ -235,17 +247,26 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_local *local = sdata->local;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	u8 *pos, *ies, *ht_ie;
+	u8 *pos, *ies, *ht_ie, *e_ies;
 	int i, len, count, rates_len, supp_rates_len;
 	u16 capab;
 	struct ieee80211_bss *bss;
 	int wmm = 0;
 	struct ieee80211_supported_band *sband;
 	u64 rates = 0;
+	size_t e_ies_len;
+
+	if (ifsta->flags & IEEE80211_STA_PREV_BSSID_SET) {
+		e_ies = sdata->u.sta.ie_reassocreq;
+		e_ies_len = sdata->u.sta.ie_reassocreq_len;
+	} else {
+		e_ies = sdata->u.sta.ie_assocreq;
+		e_ies_len = sdata->u.sta.ie_assocreq_len;
+	}
 
 	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
 			    sizeof(*mgmt) + 200 + ifsta->extra_ie_len +
-			    ifsta->ssid_len);
+			    ifsta->ssid_len + e_ies_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for assoc "
 		       "frame\n", sdata->dev->name);
@@ -436,6 +457,8 @@ static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata,
 		memcpy(pos, &sband->ht_cap.mcs, sizeof(sband->ht_cap.mcs));
 	}
 
+	add_extra_ies(skb, e_ies, e_ies_len);
+
 	kfree(ifsta->assocreq_ies);
 	ifsta->assocreq_ies_len = (skb->data + skb->len) - ies;
 	ifsta->assocreq_ies = kmalloc(ifsta->assocreq_ies_len, GFP_KERNEL);
@@ -453,8 +476,19 @@ static void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
+	u8 *ies;
+	size_t ies_len;
 
-	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt));
+	if (stype == IEEE80211_STYPE_DEAUTH) {
+		ies = sdata->u.sta.ie_deauth;
+		ies_len = sdata->u.sta.ie_deauth_len;
+	} else {
+		ies = sdata->u.sta.ie_disassoc;
+		ies_len = sdata->u.sta.ie_disassoc_len;
+	}
+
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*mgmt) +
+			    ies_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for "
 		       "deauth/disassoc frame\n", sdata->dev->name);
@@ -472,6 +506,8 @@ static void ieee80211_send_deauth_disassoc(struct ieee80211_sub_if_data *sdata,
 	/* u.deauth.reason_code == u.disassoc.reason_code */
 	mgmt->u.deauth.reason_code = cpu_to_le16(reason);
 
+	add_extra_ies(skb, ies, ies_len);
+
 	ieee80211_tx_skb(sdata, skb, ifsta->flags & IEEE80211_STA_MFP_ENABLED);
 }
 
@@ -1473,7 +1509,8 @@ static int ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_supported_band *sband;
 	union iwreq_data wrqu;
 
-	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400 +
+			    sdata->u.sta.ie_proberesp_len);
 	if (!skb) {
 		printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
 		       "response\n", sdata->dev->name);
@@ -1556,6 +1593,9 @@ static int ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		memcpy(pos, &bss->supp_rates[8], rates);
 	}
 
+	add_extra_ies(skb, sdata->u.sta.ie_proberesp,
+		      sdata->u.sta.ie_proberesp_len);
+
 	ifsta->probe_resp = skb;
 
 	ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);