mac80211: allow same PN for AMSDU sub-frames

Some hardware (iwlwifi an example) de-aggregate AMSDUs and copy the IV
as is to the generated MPDUs, so the same PN appears in multiple
packets without being a replay attack.  Allow driver to explicitly
indicate that a frame is allowed to have the same PN as the previous
frame.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Sara Sharon 2016-05-03 15:59:44 +03:00 committed by Johannes Berg
parent 20eb7ea93f
commit f631a77ba9
2 changed files with 17 additions and 5 deletions

View file

@ -1068,6 +1068,9 @@ ieee80211_tx_info_clear_status(struct ieee80211_tx_info *info)
* @RX_FLAG_RADIOTAP_VENDOR_DATA: This frame contains vendor-specific
* radiotap data in the skb->data (before the frame) as described by
* the &struct ieee80211_vendor_radiotap.
* @RX_FLAG_ALLOW_SAME_PN: Allow the same PN as same packet before.
* This is used for AMSDU subframes which can have the same PN as
* the first subframe.
*/
enum mac80211_rx_flags {
RX_FLAG_MMIC_ERROR = BIT(0),
@ -1101,7 +1104,8 @@ enum mac80211_rx_flags {
RX_FLAG_5MHZ = BIT(29),
RX_FLAG_AMSDU_MORE = BIT(30),
RX_FLAG_RADIOTAP_VENDOR_DATA = BIT(31),
RX_FLAG_MIC_STRIPPED = BIT_ULL(32),
RX_FLAG_MIC_STRIPPED = BIT_ULL(32),
RX_FLAG_ALLOW_SAME_PN = BIT_ULL(33),
};
#define RX_FLAG_STBC_SHIFT 26

View file

@ -519,12 +519,16 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
return RX_DROP_UNUSABLE;
if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
int res;
ccmp_hdr2pn(pn, skb->data + hdrlen);
queue = rx->security_idx;
if (memcmp(pn, key->u.ccmp.rx_pn[queue],
IEEE80211_CCMP_PN_LEN) <= 0) {
res = memcmp(pn, key->u.ccmp.rx_pn[queue],
IEEE80211_CCMP_PN_LEN);
if (res < 0 ||
(!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
key->u.ccmp.replays++;
return RX_DROP_UNUSABLE;
}
@ -745,12 +749,16 @@ ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
return RX_DROP_UNUSABLE;
if (!(status->flag & RX_FLAG_PN_VALIDATED)) {
int res;
gcmp_hdr2pn(pn, skb->data + hdrlen);
queue = rx->security_idx;
if (memcmp(pn, key->u.gcmp.rx_pn[queue],
IEEE80211_GCMP_PN_LEN) <= 0) {
res = memcmp(pn, key->u.gcmp.rx_pn[queue],
IEEE80211_GCMP_PN_LEN);
if (res < 0 ||
(!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
key->u.gcmp.replays++;
return RX_DROP_UNUSABLE;
}