Return-path: Received: from mail-yw0-f46.google.com ([209.85.213.46]:49681 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752932Ab2FOCV0 (ORCPT ); Thu, 14 Jun 2012 22:21:26 -0400 Received: by yhmm54 with SMTP id m54so2100466yhm.19 for ; Thu, 14 Jun 2012 19:21:25 -0700 (PDT) From: Chun-Yeow Yeoh To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, linville@tuxdriver.com, devel@lists.open80211s.org, Chun-Yeow Yeoh Subject: [PATCH] mac80211: fix and improve mesh RANN processing Date: Fri, 15 Jun 2012 10:20:02 +0800 Message-Id: <1339726802-14441-1-git-send-email-yeohchunyeow@gmail.com> (sfid-20120615_042130_403599_2E22BADB) Sender: linux-wireless-owner@vger.kernel.org List-ID: This patch fixes the problem of dropping RANN element if the TTL is 1. If the received RANN element TTL is 1 or greater than 1, the RANN is processed. However, forwarding of received RANN element with TTL 1 or less is prohibited according to the standard. This is previously reported by Monthadar Al Jaberi. Besides, this patch also avoid the processing of unicast PREQ generation if the RANN element does not meet the acceptance criteria mentioned in Sec. 13.10.12.4.2 of IEEE Std. 802.11-2012. Reported-by: Monthadar Al Jaberi Signed-off-by: Chun-Yeow Yeoh --- net/mac80211/mesh_hwmp.c | 43 +++++++++++++++++++++++++------------------ 1 files changed, 25 insertions(+), 18 deletions(-) diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c index 616c940..d0e925d 100644 --- a/net/mac80211/mesh_hwmp.c +++ b/net/mac80211/mesh_hwmp.c @@ -772,11 +772,6 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, bool root_is_gate; ttl = rann->rann_ttl; - if (ttl <= 1) { - ifmsh->mshstats.dropped_frames_ttl++; - return; - } - ttl--; flags = rann->rann_flags; root_is_gate = !!(flags & RANN_FLAG_IS_GATE); orig_addr = rann->rann_addr; @@ -813,37 +808,49 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata, } } + if (!(SN_LT(mpath->sn, orig_sn)) && + !(mpath->sn == orig_sn && metric < mpath->rann_metric)) { + rcu_read_unlock(); + return; + } + if ((!(mpath->flags & (MESH_PATH_ACTIVE | MESH_PATH_RESOLVING)) || (time_after(jiffies, mpath->last_preq_to_root + root_path_confirmation_jiffies(sdata)) || time_before(jiffies, mpath->last_preq_to_root))) && - !(mpath->flags & MESH_PATH_FIXED)) { + !(mpath->flags & MESH_PATH_FIXED) && (ttl != 0)) { mhwmp_dbg("%s time to refresh root mpath %pM", sdata->name, orig_addr); mesh_queue_preq(mpath, PREQ_Q_F_START | PREQ_Q_F_REFRESH); mpath->last_preq_to_root = jiffies; } - if ((SN_LT(mpath->sn, orig_sn) || (mpath->sn == orig_sn && - metric < mpath->rann_metric)) && ifmsh->mshcfg.dot11MeshForwarding) { + mpath->sn = orig_sn; + mpath->rann_metric = metric + metric_txsta; + mpath->is_root = true; + /* Recording RANNs sender address to send individually + * addressed PREQs destined for root mesh STA */ + memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); + + if (root_is_gate) + mesh_path_add_gate(mpath); + + if (ttl <= 1) { + ifmsh->mshstats.dropped_frames_ttl++; + rcu_read_unlock(); + return; + } + ttl--; + + if (ifmsh->mshcfg.dot11MeshForwarding) { mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr, cpu_to_le32(orig_sn), 0, NULL, 0, broadcast_addr, hopcount, ttl, cpu_to_le32(interval), cpu_to_le32(metric + metric_txsta), 0, sdata); - mpath->sn = orig_sn; - mpath->rann_metric = metric + metric_txsta; - /* Recording RANNs sender address to send individually - * addressed PREQs destined for root mesh STA */ - memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN); } - mpath->is_root = true; - - if (root_is_gate) - mesh_path_add_gate(mpath); - rcu_read_unlock(); } -- 1.7.0.4