1 files changed, 55 insertions, 26 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 6513bc2d2707..ce62b163b82c 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -45,38 +45,37 @@ const unsigned char bridge_tunnel_header[] __aligned(2) =
 u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
                         enum ieee80211_if_types type)
 {
-        u16 fc;
+        __le16 fc = hdr->frame_control;
 
          /* drop ACK/CTS frames and incorrect hdr len (ctrl) */
         if (len < 16)
                 return NULL;
 
-        fc = le16_to_cpu(hdr->frame_control);
-
-        switch (fc & IEEE80211_FCTL_FTYPE) {
-        case IEEE80211_FTYPE_DATA:
+        if (ieee80211_is_data(fc)) {
                 if (len < 24) /* drop incorrect hdr len (data) */
                         return NULL;
-                switch (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
-                case IEEE80211_FCTL_TODS:
-                        return hdr->addr1;
-                case (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
+
+                if (ieee80211_has_a4(fc))
                         return NULL;
-                case IEEE80211_FCTL_FROMDS:
+                if (ieee80211_has_tods(fc))
+                        return hdr->addr1;
+                if (ieee80211_has_fromds(fc))
                         return hdr->addr2;
-                case 0:
-                        return hdr->addr3;
-                }
-                break;
-        case IEEE80211_FTYPE_MGMT:
+
+                return hdr->addr3;
+        }
+
+        if (ieee80211_is_mgmt(fc)) {
                 if (len < 24) /* drop incorrect hdr len (mgmt) */
                         return NULL;
                 return hdr->addr3;
-        case IEEE80211_FTYPE_CTL:
-                if ((fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_PSPOLL)
+        }
+
+        if (ieee80211_is_ctl(fc)) {
+                if(ieee80211_is_pspoll(fc))
                         return hdr->addr1;
-                else if ((fc & IEEE80211_FCTL_STYPE) ==
-                                                IEEE80211_STYPE_BACK_REQ) {
+
+                if (ieee80211_is_back_req(fc)) {
                         switch (type) {
                         case IEEE80211_IF_TYPE_STA:
                                 return hdr->addr2;
@@ -84,11 +83,9 @@ u8 *ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len,
                         case IEEE80211_IF_TYPE_VLAN:
                                 return hdr->addr1;
                         default:
-                                return NULL;
+                                break; /* fall through to the return */
                         }
                 }
-                else
-                        return NULL;
         }
 
         return NULL;
@@ -133,14 +130,46 @@ int ieee80211_get_hdrlen(u16 fc)
 }
 EXPORT_SYMBOL(ieee80211_get_hdrlen);
 
-int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
+unsigned int ieee80211_hdrlen(__le16 fc)
+{
+        unsigned int hdrlen = 24;
+
+        if (ieee80211_is_data(fc)) {
+                if (ieee80211_has_a4(fc))
+                        hdrlen = 30;
+                if (ieee80211_is_data_qos(fc))
+                        hdrlen += IEEE80211_QOS_CTL_LEN;
+                goto out;
+        }
+
+        if (ieee80211_is_ctl(fc)) {
+                /*
+                 * ACK and CTS are 10 bytes, all others 16. To see how
+                 * to get this condition consider
+                 *   subtype mask:   0b0000000011110000 (0x00F0)
+                 *   ACK subtype:    0b0000000011010000 (0x00D0)
+                 *   CTS subtype:    0b0000000011000000 (0x00C0)
+                 *   bits that matter:         ^^^      (0x00E0)
+                 *   value of those: 0b0000000011000000 (0x00C0)
+                 */
+                if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
+                        hdrlen = 10;
+                else
+                        hdrlen = 16;
+        }
+out:
+        return hdrlen;
+}
+EXPORT_SYMBOL(ieee80211_hdrlen);
+
+unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 {
-        const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *) skb->data;
-        int hdrlen;
+        const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *)skb->data;
+        unsigned int hdrlen;
 
         if (unlikely(skb->len < 10))
                 return 0;
-        hdrlen = ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control));
+        hdrlen = ieee80211_hdrlen(hdr->frame_control);
         if (unlikely(hdrlen > skb->len))
                 return 0;
         return hdrlen;