From f631a77ba920f7153a1094d09cd8f2ebbffd0328 Mon Sep 17 00:00:00 2001 From: Sara Sharon Date: Tue, 3 May 2016 15:59:44 +0300 Subject: [PATCH] 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 Signed-off-by: Luca Coelho Signed-off-by: Johannes Berg --- include/net/mac80211.h | 6 +++++- net/mac80211/wpa.c | 16 ++++++++++++---- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 07ef9378df2b..ce2f6e3be3cf 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -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 diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index 7e4f2652bca7..b48c1e13e281 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -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; } -- 2.11.0