Commit 761ab470 authored by Johannes Berg's avatar Johannes Berg Committed by John W. Linville

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: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 6a8579d0
...@@ -825,6 +825,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -825,6 +825,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
ieee80211_rx_result result = RX_DROP_UNUSABLE; ieee80211_rx_result result = RX_DROP_UNUSABLE;
struct ieee80211_key *stakey = NULL; struct ieee80211_key *stakey = NULL;
int mmie_keyidx = -1; int mmie_keyidx = -1;
__le16 fc;
/* /*
* Key selection 101 * Key selection 101
...@@ -866,13 +867,15 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -866,13 +867,15 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
if (rx->sta) if (rx->sta)
stakey = rcu_dereference(rx->sta->key); 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); mmie_keyidx = ieee80211_get_mmie_keyidx(rx->skb);
if (!is_multicast_ether_addr(hdr->addr1) && stakey) { if (!is_multicast_ether_addr(hdr->addr1) && stakey) {
rx->key = stakey; rx->key = stakey;
/* Skip decryption if the frame is not protected. */ /* Skip decryption if the frame is not protected. */
if (!ieee80211_has_protected(hdr->frame_control)) if (!ieee80211_has_protected(fc))
return RX_CONTINUE; return RX_CONTINUE;
} else if (mmie_keyidx >= 0) { } else if (mmie_keyidx >= 0) {
/* Broadcast/multicast robust management frame / BIP */ /* Broadcast/multicast robust management frame / BIP */
...@@ -884,7 +887,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -884,7 +887,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
return RX_DROP_MONITOR; /* unexpected BIP keyidx */ return RX_DROP_MONITOR; /* unexpected BIP keyidx */
rx->key = rcu_dereference(rx->sdata->keys[mmie_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 * The frame was not protected, so skip decryption. However, we
* need to set rx->key if there is a key that could have been * need to set rx->key if there is a key that could have been
...@@ -892,7 +895,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -892,7 +895,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
* have been expected. * have been expected.
*/ */
struct ieee80211_key *key = NULL; struct ieee80211_key *key = NULL;
if (ieee80211_is_mgmt(hdr->frame_control) && if (ieee80211_is_mgmt(fc) &&
is_multicast_ether_addr(hdr->addr1) && is_multicast_ether_addr(hdr->addr1) &&
(key = rcu_dereference(rx->sdata->default_mgmt_key))) (key = rcu_dereference(rx->sdata->default_mgmt_key)))
rx->key = key; rx->key = key;
...@@ -914,7 +917,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -914,7 +917,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
(status->flag & RX_FLAG_IV_STRIPPED)) (status->flag & RX_FLAG_IV_STRIPPED))
return RX_CONTINUE; return RX_CONTINUE;
hdrlen = ieee80211_hdrlen(hdr->frame_control); hdrlen = ieee80211_hdrlen(fc);
if (rx->skb->len < 8 + hdrlen) if (rx->skb->len < 8 + hdrlen)
return RX_DROP_UNUSABLE; /* TODO: count this? */ return RX_DROP_UNUSABLE; /* TODO: count this? */
...@@ -947,19 +950,17 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) ...@@ -947,19 +950,17 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
if (skb_linearize(rx->skb)) if (skb_linearize(rx->skb))
return RX_DROP_UNUSABLE; return RX_DROP_UNUSABLE;
/* the hdr variable is invalid now! */
hdr = (struct ieee80211_hdr *)rx->skb->data; switch (rx->key->conf.alg) {
case ALG_WEP:
/* Check for weak IVs if possible */ /* Check for weak IVs if possible */
if (rx->sta && rx->key->conf.alg == ALG_WEP && if (rx->sta && ieee80211_is_data(fc) &&
ieee80211_is_data(hdr->frame_control) &&
(!(status->flag & RX_FLAG_IV_STRIPPED) || (!(status->flag & RX_FLAG_IV_STRIPPED) ||
!(status->flag & RX_FLAG_DECRYPTED)) && !(status->flag & RX_FLAG_DECRYPTED)) &&
ieee80211_wep_is_weak_iv(rx->skb, rx->key)) ieee80211_wep_is_weak_iv(rx->skb, rx->key))
rx->sta->wep_weak_iv_count++; rx->sta->wep_weak_iv_count++;
switch (rx->key->conf.alg) {
case ALG_WEP:
result = ieee80211_crypto_wep_decrypt(rx); result = ieee80211_crypto_wep_decrypt(rx);
break; break;
case ALG_TKIP: case ALG_TKIP:
......
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