diff options
Diffstat (limited to 'net/mac80211/rx.c')
| -rw-r--r-- | net/mac80211/rx.c | 79 |
1 files changed, 67 insertions, 12 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index ec3a04a..6bd2412 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -983,7 +983,8 @@ static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da)) return -1; - if (!ieee80211_is_robust_mgmt_frame(skb)) + if (!ieee80211_is_robust_mgmt_frame(skb) && + !ieee80211_is_beacon(hdr->frame_control)) return -1; /* not a robust management frame */ mmie = (struct ieee80211_mmie *) @@ -1868,6 +1869,41 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx) return RX_CONTINUE; } /* ieee80211_rx_h_sta_process */ +static struct ieee80211_key * +ieee80211_rx_get_bigtk(struct ieee80211_rx_data *rx, int idx) +{ + struct ieee80211_key *key = NULL; + struct ieee80211_sub_if_data *sdata = rx->sdata; + int idx2; + + /* Make sure key gets set if either BIGTK key index is set so that + * ieee80211_drop_unencrypted_mgmt() can properly drop both unprotected + * Beacon frames and Beacon frames that claim to use another BIGTK key + * index (i.e., a key that we do not have). + */ + + if (idx < 0) { + idx = NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS; + idx2 = idx + 1; + } else { + if (idx == NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) + idx2 = idx + 1; + else + idx2 = idx - 1; + } + + if (rx->sta) + key = rcu_dereference(rx->sta->gtk[idx]); + if (!key) + key = rcu_dereference(sdata->keys[idx]); + if (!key && rx->sta) + key = rcu_dereference(rx->sta->gtk[idx2]); + if (!key) + key = rcu_dereference(sdata->keys[idx2]); + + return key; +} + static ieee80211_rx_result debug_noinline ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) { @@ -1885,17 +1921,18 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) /* * Key selection 101 * - * There are four types of keys: + * There are five types of keys: * - GTK (group keys) * - IGTK (group keys for management frames) + * - BIGTK (group keys for Beacon frames) * - PTK (pairwise keys) * - STK (station-to-station pairwise keys) * * When selecting a key, we have to distinguish between multicast * (including broadcast) and unicast frames, the latter can only - * use PTKs and STKs while the former always use GTKs and IGTKs. - * Unless, of course, actual WEP keys ("pre-RSNA") are used, then - * unicast frames can also use key indices like GTKs. Hence, if we + * use PTKs and STKs while the former always use GTKs, IGTKs, and + * BIGTKs. Unless, of course, actual WEP keys ("pre-RSNA") are used, + * then unicast frames can also use key indices like GTKs. Hence, if we * don't have a PTK/STK we check the key index for a WEP key. * * Note that in a regular BSS, multicast frames are sent by the @@ -1939,6 +1976,20 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) /* Skip decryption if the frame is not protected. */ if (!ieee80211_has_protected(fc)) return RX_CONTINUE; + } else if (mmie_keyidx >= 0 && ieee80211_is_beacon(fc)) { + /* Broadcast/multicast robust management frame / BIP */ + if ((status->flag & RX_FLAG_DECRYPTED) && + (status->flag & RX_FLAG_IV_STRIPPED)) + return RX_CONTINUE; + + if (mmie_keyidx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS || + mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS + + NUM_DEFAULT_BEACON_KEYS) + return RX_DROP_MONITOR; /* unexpected BIP keyidx */ + + rx->key = ieee80211_rx_get_bigtk(rx, mmie_keyidx); + if (!rx->key) + return RX_CONTINUE; /* Beacon protection not in use */ } else if (mmie_keyidx >= 0) { /* Broadcast/multicast robust management frame / BIP */ if ((status->flag & RX_FLAG_DECRYPTED) && @@ -1968,11 +2019,12 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) struct ieee80211_sub_if_data *sdata = rx->sdata; int i; - if (ieee80211_is_mgmt(fc) && - is_multicast_ether_addr(hdr->addr1) && - (key = rcu_dereference(rx->sdata->default_mgmt_key))) - rx->key = key; - else { + if (ieee80211_is_beacon(fc)) { + key = ieee80211_rx_get_bigtk(rx, -1); + } else if (ieee80211_is_mgmt(fc) && + is_multicast_ether_addr(hdr->addr1)) { + key = rcu_dereference(rx->sdata->default_mgmt_key); + } else { if (rx->sta) { for (i = 0; i < NUM_DEFAULT_KEYS; i++) { key = rcu_dereference(rx->sta->gtk[i]); @@ -1987,9 +2039,9 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) break; } } - if (key) - rx->key = key; } + if (key) + rx->key = key; return RX_CONTINUE; } else { /* @@ -2358,6 +2410,9 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx) rx->skb->len); return -EACCES; } + if (unlikely(ieee80211_is_beacon(fc) && rx->key && + ieee80211_get_mmie_keyidx(rx->skb) < 0)) + return -EACCES; /* * When using MFP, Action frames are not allowed prior to * having configured keys. |