iwlwifi: mvm: check PN for CCMP/GCMP in the driver
As we're working on multi-queue RX, we want to parallelise checking
the PN in order to avoid having to serialise the RX processing.
It may seem that doing parallel PN checking is insecure, but it turns
out to be OK because queue assignment is done based on the data in the
frame (IP/TCP) and thus cannot be manipulated by an attacker, since
the data is encrypted and must first have been decrypted successfully.
There are some corner cases, in particular when the peer starts using
fragmentation which redirects the packet to the default queue. However
this redirection is remembered (for the STA, per TID) and thus cannot
be exploited by an attacker either.
Leave checking on the default queue (queue 0) to mac80211, since we
get fragmented packets there and those are subject to stricter checks
during reassembly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index 40b5c53..d70a171 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -2568,6 +2568,9 @@
struct ieee80211_key_conf *key)
{
struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
+ struct iwl_mvm_sta *mvmsta;
+ struct iwl_mvm_key_pn *ptk_pn;
+ int keyidx = key->keyidx;
int ret;
u8 key_offset;
@@ -2635,6 +2638,36 @@
break;
}
+ if (!test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status) &&
+ sta && iwl_mvm_has_new_rx_api(mvm) &&
+ key->flags & IEEE80211_KEY_FLAG_PAIRWISE &&
+ (key->cipher == WLAN_CIPHER_SUITE_CCMP ||
+ key->cipher == WLAN_CIPHER_SUITE_GCMP)) {
+ struct ieee80211_key_seq seq;
+ int tid, q;
+
+ mvmsta = iwl_mvm_sta_from_mac80211(sta);
+ WARN_ON(rcu_access_pointer(mvmsta->ptk_pn[keyidx]));
+ ptk_pn = kzalloc(sizeof(*ptk_pn) +
+ mvm->trans->num_rx_queues *
+ sizeof(ptk_pn->q[0]),
+ GFP_KERNEL);
+ if (!ptk_pn) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ for (tid = 0; tid < IWL_MAX_TID_COUNT; tid++) {
+ ieee80211_get_key_rx_seq(key, tid, &seq);
+ for (q = 0; q < mvm->trans->num_rx_queues; q++)
+ memcpy(ptk_pn->q[q].pn[tid],
+ seq.ccmp.pn,
+ IEEE80211_CCMP_PN_LEN);
+ }
+
+ rcu_assign_pointer(mvmsta->ptk_pn[keyidx], ptk_pn);
+ }
+
/* in HW restart reuse the index, otherwise request a new one */
if (test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status))
key_offset = key->hw_key_idx;
@@ -2660,6 +2693,19 @@
break;
}
+ if (sta && iwl_mvm_has_new_rx_api(mvm) &&
+ key->flags & IEEE80211_KEY_FLAG_PAIRWISE &&
+ (key->cipher == WLAN_CIPHER_SUITE_CCMP ||
+ key->cipher == WLAN_CIPHER_SUITE_GCMP)) {
+ mvmsta = iwl_mvm_sta_from_mac80211(sta);
+ ptk_pn = rcu_dereference_protected(
+ mvmsta->ptk_pn[keyidx],
+ lockdep_is_held(&mvm->mutex));
+ RCU_INIT_POINTER(mvmsta->ptk_pn[keyidx], NULL);
+ if (ptk_pn)
+ kfree_rcu(ptk_pn, rcu_head);
+ }
+
IWL_DEBUG_MAC80211(mvm, "disable hwcrypto key\n");
ret = iwl_mvm_remove_sta_key(mvm, vif, sta, key);
break;