[PATCH] mac80211: fix TKIP IV update
authorJohannes Berg <johannes@sipsolutions.net>
Wed, 26 Sep 2007 13:19:45 +0000 (15:19 +0200)
committerDavid S. Miller <davem@sunset.davemloft.net>
Wed, 10 Oct 2007 23:53:16 +0000 (16:53 -0700)
The TKIP IV should be updated only after MMIC verification,
this patch changes it to be at that spot.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
net/mac80211/ieee80211_i.h
net/mac80211/tkip.c
net/mac80211/tkip.h
net/mac80211/wpa.c

index 636de70cd85dd5724de6a99c1999ec04c3b45f4d..32d19bbf522c5e7f9040219b98d0b1168bc1816f 100644 (file)
@@ -153,6 +153,8 @@ struct ieee80211_txrx_data {
                        int sent_ps_buffered;
                        int queue;
                        int load;
+                       u32 tkip_iv32;
+                       u16 tkip_iv16;
                } rx;
        } u;
 };
index 5b11f14abfba5451c6a0d198e816c3958148dce5..3abe194e4d55328ae61aba0bdcd1515a299212fd 100644 (file)
@@ -238,7 +238,8 @@ void ieee80211_tkip_encrypt_data(struct crypto_blkcipher *tfm,
 int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm,
                                struct ieee80211_key *key,
                                u8 *payload, size_t payload_len, u8 *ta,
-                               int only_iv, int queue)
+                               int only_iv, int queue,
+                               u32 *out_iv32, u16 *out_iv16)
 {
        u32 iv32;
        u32 iv16;
@@ -332,11 +333,14 @@ int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm,
        res = ieee80211_wep_decrypt_data(tfm, rc4key, 16, pos, payload_len - 12);
  done:
        if (res == TKIP_DECRYPT_OK) {
-               /* FIX: these should be updated only after Michael MIC has been
-                * verified */
-               /* Record previously received IV */
-               key->u.tkip.iv32_rx[queue] = iv32;
-               key->u.tkip.iv16_rx[queue] = iv16;
+               /*
+                * Record previously received IV, will be copied into the
+                * key information after MIC verification. It is possible
+                * that we don't catch replays of fragments but that's ok
+                * because the Michael MIC verication will then fail.
+                */
+               *out_iv32 = iv32;
+               *out_iv16 = iv16;
        }
 
        return res;
index a0d181a180495f786156790bbec9dc4470ce7430..73d8ef2a93b0f9ed5821d3a0686b44e65f6e0c63 100644 (file)
@@ -31,6 +31,7 @@ enum {
 int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm,
                                struct ieee80211_key *key,
                                u8 *payload, size_t payload_len, u8 *ta,
-                               int only_iv, int queue);
+                               int only_iv, int queue,
+                               u32 *out_iv32, u16 *out_iv16);
 
 #endif /* TKIP_H */
index a07fd7484cdfa9bc5c90127fcd8884af6b3a1fa1..6695efba57ec12c52329c203da57d97d45f7946b 100644 (file)
@@ -175,6 +175,10 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx)
        /* remove Michael MIC from payload */
        skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
 
+       /* update IV in key information to be able to detect replays */
+       rx->key->u.tkip.iv32_rx[rx->u.rx.queue] = rx->u.rx.tkip_iv32;
+       rx->key->u.tkip.iv16_rx[rx->u.rx.queue] = rx->u.rx.tkip_iv16;
+
        return TXRX_CONTINUE;
 }
 
@@ -315,7 +319,9 @@ ieee80211_crypto_tkip_decrypt(struct ieee80211_txrx_data *rx)
        res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,
                                          key, skb->data + hdrlen,
                                          skb->len - hdrlen, rx->sta->addr,
-                                         hwaccel, rx->u.rx.queue);
+                                         hwaccel, rx->u.rx.queue,
+                                         &rx->u.rx.tkip_iv32,
+                                         &rx->u.rx.tkip_iv16);
        if (res != TKIP_DECRYPT_OK || wpa_test) {
                printk(KERN_DEBUG "%s: TKIP decrypt failed for RX frame from "
                       "%s (res=%d)\n",