From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pa0-f68.google.com ([209.85.220.68]:34754 "EHLO mail-pa0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752048AbcF2PIm (ORCPT ); Wed, 29 Jun 2016 11:08:42 -0400 Received: by mail-pa0-f68.google.com with SMTP id us13so4629496pab.1 for ; Wed, 29 Jun 2016 08:08:07 -0700 (PDT) Subject: Re: [PATCH v3] mac80211: Encrypt "Group addressed privacy" action frames To: j@w1.fi, johannes@sipsolutions.net References: <20160621170120.GA24882@w1.fi> <1466592920-2716-1-git-send-email-masashi.honma@gmail.com> Cc: linux-wireless@vger.kernel.org From: Masashi Honma Message-ID: <5773E453.9060206@gmail.com> (sfid-20160629_170847_432004_2572A5CD) Date: Thu, 30 Jun 2016 00:08:03 +0900 MIME-Version: 1.0 In-Reply-To: <1466592920-2716-1-git-send-email-masashi.honma@gmail.com> Content-Type: text/plain; charset=iso-2022-jp Sender: linux-wireless-owner@vger.kernel.org List-ID: On 2016年06月22日 19:55, Masashi Honma wrote: > Previously, the action frames to group address was not encrypted. But > [1] "Table 8-38 Category values" indicates "Mesh" and "Multihop" category > action frames should be encrypted (Group addressed privacy == yes). And the > encyption key should be MGTK ([1] 10.13 Group addressed robust management frame > procedures). So this patch modifies the code to make it suitable for spec. > > [1] IEEE Std 802.11-2012 > > Signed-off-by: Masashi Honma > --- > include/linux/ieee80211.h | 32 ++++++++++++++++++++++++++++++++ > net/mac80211/rx.c | 7 ++++++- > net/mac80211/tx.c | 6 +++++- > 3 files changed, 43 insertions(+), 2 deletions(-) > > diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h > index b118744..7c0771a 100644 > --- a/include/linux/ieee80211.h > +++ b/include/linux/ieee80211.h > @@ -19,6 +19,7 @@ > > #include > #include > +#include > #include > #include > > @@ -2487,6 +2488,37 @@ static inline bool ieee80211_is_public_action(struct ieee80211_hdr *hdr, > } > > /** > + * _ieee80211_is_group_privacy_action - check if frame is a group addressed > + * privacy action frame > + * @hdr: the frame > + */ > +static inline bool _ieee80211_is_group_privacy_action(struct ieee80211_hdr *hdr) > +{ > + struct ieee80211_mgmt *mgmt; > + > + if (!ieee80211_is_action(hdr->frame_control) || > + !is_multicast_ether_addr(hdr->addr1)) > + return false; > + > + mgmt = (struct ieee80211_mgmt *)hdr; > + > + return mgmt->u.action.category == WLAN_CATEGORY_MESH_ACTION || > + mgmt->u.action.category == WLAN_CATEGORY_MULTIHOP_ACTION; > +} > + > +/** > + * ieee80211_is_group_privacy_action - check if frame is a group addressed > + * privacy action frame > + * @skb: the skb containing the frame, length will be checked > + */ > +static inline bool ieee80211_is_group_privacy_action(struct sk_buff *skb) > +{ > + if (skb->len < IEEE80211_MIN_ACTION_SIZE) > + return false; > + return _ieee80211_is_group_privacy_action((void *)skb->data); > +} > + > +/** > * ieee80211_tu_to_usec - convert time units (TU) to microseconds > * @tu: the TUs > */ > diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c > index 5e65e83..2300c0f 100644 > --- a/net/mac80211/rx.c > +++ b/net/mac80211/rx.c > @@ -1624,8 +1624,13 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) > if (mmie_keyidx < NUM_DEFAULT_KEYS || > mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS) > return RX_DROP_MONITOR; /* unexpected BIP keyidx */ > - if (rx->sta) > + if (rx->sta) { > + if (ieee80211_is_group_privacy_action(skb) && > + test_sta_flag(rx->sta, WLAN_STA_MFP)) > + return RX_DROP_MONITOR; > + > rx->key = rcu_dereference(rx->sta->gtk[mmie_keyidx]); > + } > if (!rx->key) > rx->key = rcu_dereference(rx->sdata->keys[mmie_keyidx]); > } else if (!ieee80211_has_protected(fc)) { > diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c > index 2030443..e194df6 100644 > --- a/net/mac80211/tx.c > +++ b/net/mac80211/tx.c > @@ -590,6 +590,9 @@ ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) > else if (tx->sta && > (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx]))) > tx->key = key; > + else if (ieee80211_is_group_privacy_action(tx->skb) && > + (key = rcu_dereference(tx->sdata->default_multicast_key))) > + tx->key = key; > else if (ieee80211_is_mgmt(hdr->frame_control) && > is_multicast_ether_addr(hdr->addr1) && > ieee80211_is_robust_mgmt_frame(tx->skb) && > @@ -622,7 +625,8 @@ ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) > case WLAN_CIPHER_SUITE_GCMP_256: > if (!ieee80211_is_data_present(hdr->frame_control) && > !ieee80211_use_mfp(hdr->frame_control, tx->sta, > - tx->skb)) > + tx->skb) && > + !ieee80211_is_group_privacy_action(tx->skb)) > tx->key = NULL; > else > skip_hw = (tx->key->conf.flags & Is there any comment about this ?