mac80211: create Probe Request template

Certain type of hardware, for example wl1251 and wl1271, need a template
for the Probe Request. Create a function ieee80211_probereq_get() which
creates the template and drivers send it to hardware.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 055b45b146d9..0661e696a1dd 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2278,6 +2278,56 @@ struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_nullfunc_get);
 
+struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
+                                       struct ieee80211_vif *vif,
+                                       const u8 *ssid, size_t ssid_len,
+                                       const u8 *ie, size_t ie_len)
+{
+        struct ieee80211_sub_if_data *sdata;
+        struct ieee80211_local *local;
+        struct ieee80211_hdr_3addr *hdr;
+        struct sk_buff *skb;
+        size_t ie_ssid_len;
+        u8 *pos;
+
+        sdata = vif_to_sdata(vif);
+        local = sdata->local;
+        ie_ssid_len = 2 + ssid_len;
+
+        skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
+                            ie_ssid_len + ie_len);
+        if (!skb) {
+                printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
+                       "request template\n", sdata->name);
+                return NULL;
+        }
+
+        skb_reserve(skb, local->hw.extra_tx_headroom);
+
+        hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
+        memset(hdr, 0, sizeof(*hdr));
+        hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+                                         IEEE80211_STYPE_PROBE_REQ);
+        memset(hdr->addr1, 0xff, ETH_ALEN);
+        memcpy(hdr->addr2, vif->addr, ETH_ALEN);
+        memset(hdr->addr3, 0xff, ETH_ALEN);
+
+        pos = skb_put(skb, ie_ssid_len);
+        *pos++ = WLAN_EID_SSID;
+        *pos++ = ssid_len;
+        if (ssid)
+                memcpy(pos, ssid, ssid_len);
+        pos += ssid_len;
+
+        if (ie) {
+                pos = skb_put(skb, ie_len);
+                memcpy(pos, ie, ie_len);
+        }
+
+        return skb;
+}
+EXPORT_SYMBOL(ieee80211_probereq_get);
+
 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                        const void *frame, size_t frame_len,
                        const struct ieee80211_tx_info *frame_txctl,