Return-path: Received: from mail.fem.tu-ilmenau.de ([141.24.220.54]:39606 "EHLO mail.fem.tu-ilmenau.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755152AbcJMFnx (ORCPT ); Thu, 13 Oct 2016 01:43:53 -0400 From: Michael Braun To: johannes@sipsolutions.net Cc: Michael Braun , linux-wireless@vger.kernel.org, projekt-wlan@fem.tu-ilmenau.de, Felix Fietkau Subject: [PATCHv4] mac80211: fix A-MSDU outer SA/DA Date: Thu, 13 Oct 2016 07:41:55 +0200 Message-Id: <1476337315-26845-1-git-send-email-michael-dev@fami-braun.de> (sfid-20161013_074406_501207_29437AE6) Sender: linux-wireless-owner@vger.kernel.org List-ID: According to IEEE 802.11-2012 section 8.3.2 table 8-19, the outer SA/DA of A-MSDU frames need to be changed depending on FromDS/ToDS values. Signed-off-by: Michael Braun -- v4: - h_80211_src/dst has been memmove'd and thus needs to be fixed v3: - write to outer 802.11 header instead of inner amsdu subframe header v2: - avoid the extra write to amsdu_hdr - avoid copy of asmdu_hdr into skb, use ptr instead --- net/mac80211/tx.c | 46 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 36 insertions(+), 10 deletions(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 5023966..5f80b94 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -3046,11 +3046,12 @@ static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata, struct ieee80211_local *local = sdata->local; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_hdr *hdr; - struct ethhdr amsdu_hdr; + struct ethhdr *amsdu_hdr; int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header); int subframe_len = skb->len - hdr_len; void *data; - u8 *qc; + u8 *qc, *h_80211_src, *h_80211_dst; + const u8 *bssid; if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) return false; @@ -3058,19 +3059,44 @@ static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata, if (info->control.flags & IEEE80211_TX_CTRL_AMSDU) return true; - if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(amsdu_hdr), + if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(*amsdu_hdr), &subframe_len)) return false; - amsdu_hdr.h_proto = cpu_to_be16(subframe_len); - memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN); - memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN); + data = skb_push(skb, sizeof(*amsdu_hdr)); + memmove(data, data + sizeof(*amsdu_hdr), hdr_len); + hdr = data; + amsdu_hdr = data + hdr_len; + /* h_80211_src/dst is addr* field within hdr */ + h_80211_src = data + fast_tx->sa_offs; + h_80211_dst = data + fast_tx->da_offs; + + amsdu_hdr->h_proto = cpu_to_be16(subframe_len); + memcpy(amsdu_hdr->h_source, h_80211_src, ETH_ALEN); + memcpy(amsdu_hdr->h_dest, h_80211_dst, ETH_ALEN); + + /* according to IEEE 802.11-2012 8.3.2 table 8-19, the outer SA/DA + * fields needs to be changed to BSSID for A-MSDU frames depending + * on FromDS/ToDS values. + */ + switch (sdata->vif.type) { + case NL80211_IFTYPE_STATION: + bssid = sdata->u.mgd.bssid; + break; + case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_AP_VLAN: + bssid = sdata->vif.addr; + break; + default: + bssid = NULL; + } - data = skb_push(skb, sizeof(amsdu_hdr)); - memmove(data, data + sizeof(amsdu_hdr), hdr_len); - memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr)); + if (bssid && ieee80211_has_fromds(hdr->frame_control)) + memcpy(h_80211_src, bssid, ETH_ALEN); + + if (bssid && ieee80211_has_tods(hdr->frame_control)) + memcpy(h_80211_dst, bssid, ETH_ALEN); - hdr = data; qc = ieee80211_get_qos_ctl(hdr); *qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT; -- 2.1.4