mac80211: move WEP weak IV check
I suspect the compiler will do this optimisation
anyway, but it seems cleaner to move this into
the WEP switch case.
Also make rx_h_decrypt use a local variable for
the frame_control so that we don't need to reload
the hdr variable for this after linearizing.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 6e2a7bc..0ade267 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -825,6 +825,7 @@
ieee80211_rx_result result = RX_DROP_UNUSABLE;
struct ieee80211_key *stakey = NULL;
int mmie_keyidx = -1;
+ __le16 fc;
/*
* Key selection 101
@@ -866,13 +867,15 @@
if (rx->sta)
stakey = rcu_dereference(rx->sta->key);
- if (!ieee80211_has_protected(hdr->frame_control))
+ fc = hdr->frame_control;
+
+ if (!ieee80211_has_protected(fc))
mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
rx->key = stakey;
/* Skip decryption if the frame is not protected. */
- if (!ieee80211_has_protected(hdr->frame_control))
+ if (!ieee80211_has_protected(fc))
return RX_CONTINUE;
} else if (mmie_keyidx >= 0) {
/* Broadcast/multicast robust management frame / BIP */
@@ -884,7 +887,7 @@
mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
return RX_DROP_MONITOR; /* unexpected BIP keyidx */
rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]);
- } else if (!ieee80211_has_protected(hdr->frame_control)) {
+ } else if (!ieee80211_has_protected(fc)) {
/*
* The frame was not protected, so skip decryption. However, we
* need to set rx->key if there is a key that could have been
@@ -892,7 +895,7 @@
* have been expected.
*/
struct ieee80211_key *key = NULL;
- if (ieee80211_is_mgmt(hdr->frame_control) &&
+ if (ieee80211_is_mgmt(fc) &&
is_multicast_ether_addr(hdr->addr1) &&
(key = rcu_dereference(rx->sdata->default_mgmt_key)))
rx->key = key;
@@ -914,7 +917,7 @@
(status->flag & RX_FLAG_IV_STRIPPED))
return RX_CONTINUE;
- hdrlen = ieee80211_hdrlen(hdr->frame_control);
+ hdrlen = ieee80211_hdrlen(fc);
if (rx->skb->len < 8 + hdrlen)
return RX_DROP_UNUSABLE; /* TODO: count this? */
@@ -947,19 +950,17 @@
if (skb_linearize(rx->skb))
return RX_DROP_UNUSABLE;
-
- hdr = (struct ieee80211_hdr *)rx->skb->data;
-
- /* Check for weak IVs if possible */
- if (rx->sta && rx->key->conf.alg == ALG_WEP &&
- ieee80211_is_data(hdr->frame_control) &&
- (!(status->flag & RX_FLAG_IV_STRIPPED) ||
- !(status->flag & RX_FLAG_DECRYPTED)) &&
- ieee80211_wep_is_weak_iv(rx->skb, rx->key))
- rx->sta->wep_weak_iv_count++;
+ /* the hdr variable is invalid now! */
switch (rx->key->conf.alg) {
case ALG_WEP:
+ /* Check for weak IVs if possible */
+ if (rx->sta && ieee80211_is_data(fc) &&
+ (!(status->flag & RX_FLAG_IV_STRIPPED) ||
+ !(status->flag & RX_FLAG_DECRYPTED)) &&
+ ieee80211_wep_is_weak_iv(rx->skb, rx->key))
+ rx->sta->wep_weak_iv_count++;
+
result = ieee80211_crypto_wep_decrypt(rx);
break;
case ALG_TKIP: