mac80211: implement RANN processing and forwarding
Process the RANN (Root Annoucement) Frame and try to find the HWMP
root station by sending a PREQ.
Signed-off-by: Rui Paulo <rpaulo@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Reviewed-by: Andrey Yurovsky <andrey@cozybit.com>
Tested-by: Brian Cavagnolo <brian@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 50c684d..49b1abd 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -554,6 +554,20 @@
u8 virtual_map[1];
} __attribute__ ((packed));
+/**
+ * struct ieee80211_rann_ie
+ *
+ * This structure refers to "Root Announcement information element"
+ */
+struct ieee80211_rann_ie {
+ u8 rann_flags;
+ u8 rann_hopcount;
+ u8 rann_ttl;
+ u8 rann_addr[6];
+ u32 rann_seq;
+ u32 rann_metric;
+} __attribute__ ((packed));
+
#define WLAN_SA_QUERY_TR_ID_LEN 2
struct ieee80211_mgmt {
@@ -1070,6 +1084,7 @@
WLAN_EID_PREQ = 68,
WLAN_EID_PREP = 69,
WLAN_EID_PERR = 70,
+ WLAN_EID_RANN = 49, /* compatible with FreeBSD */
/* 802.11h */
WLAN_EID_PWR_CONSTRAINT = 32,
WLAN_EID_PWR_CAPABILITY = 33,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 19b0c12..2a7d3d4 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -804,6 +804,7 @@
u8 *preq;
u8 *prep;
u8 *perr;
+ struct ieee80211_rann_ie *rann;
u8 *ch_switch_elem;
u8 *country_elem;
u8 *pwr_constr_elem;
diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index db1a330..7b9dd87 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -28,6 +28,8 @@
/* Reply and forward */
#define MP_F_RF 0x2
+static void mesh_queue_preq(struct mesh_path *, u8);
+
static inline u32 u32_field_get(u8 *preq_elem, int offset, bool ae)
{
if (ae)
@@ -81,7 +83,8 @@
enum mpath_frame_type {
MPATH_PREQ = 0,
MPATH_PREP,
- MPATH_PERR
+ MPATH_PERR,
+ MPATH_RANN
};
static int mesh_path_sel_frame_tx(enum mpath_frame_type action, u8 flags,
@@ -109,7 +112,8 @@
memcpy(mgmt->da, da, ETH_ALEN);
memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
- /* BSSID is left zeroed, wildcard value */
+ /* BSSID == SA */
+ memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
mgmt->u.action.category = MESH_PATH_SEL_CATEGORY;
mgmt->u.action.u.mesh_action.action_code = MESH_PATH_SEL_ACTION;
@@ -126,6 +130,12 @@
pos = skb_put(skb, 2 + ie_len);
*pos++ = WLAN_EID_PREP;
break;
+ case MPATH_RANN:
+ mhwmp_dbg("sending RANN from %pM\n", orig_addr);
+ ie_len = sizeof(struct ieee80211_rann_ie);
+ pos = skb_put(skb, 2 + ie_len);
+ *pos++ = WLAN_EID_RANN;
+ break;
default:
kfree_skb(skb);
return -ENOTSUPP;
@@ -143,8 +153,10 @@
pos += ETH_ALEN;
memcpy(pos, &orig_dsn, 4);
pos += 4;
- memcpy(pos, &lifetime, 4);
- pos += 4;
+ if (action != MPATH_RANN) {
+ memcpy(pos, &lifetime, 4);
+ pos += 4;
+ }
memcpy(pos, &metric, 4);
pos += 4;
if (action == MPATH_PREQ) {
@@ -152,9 +164,11 @@
*pos++ = 1;
*pos++ = dst_flags;
}
- memcpy(pos, dst, ETH_ALEN);
- pos += ETH_ALEN;
- memcpy(pos, &dst_dsn, 4);
+ if (action != MPATH_RANN) {
+ memcpy(pos, dst, ETH_ALEN);
+ pos += ETH_ALEN;
+ memcpy(pos, &dst_dsn, 4);
+ }
ieee80211_tx_skb(sdata, skb, 1);
return 0;
@@ -610,6 +624,54 @@
rcu_read_unlock();
}
+static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_mgmt *mgmt,
+ struct ieee80211_rann_ie *rann)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct mesh_path *mpath;
+ u8 *ta;
+ u8 ttl, flags, hopcount;
+ u8 *orig_addr;
+ u32 orig_dsn, metric;
+
+ ta = mgmt->sa;
+ ttl = rann->rann_ttl;
+ if (ttl <= 1) {
+ ifmsh->mshstats.dropped_frames_ttl++;
+ return;
+ }
+ ttl--;
+ flags = rann->rann_flags;
+ orig_addr = rann->rann_addr;
+ orig_dsn = rann->rann_seq;
+ hopcount = rann->rann_hopcount;
+ metric = rann->rann_metric;
+ mhwmp_dbg("received RANN from %pM\n", orig_addr);
+
+ rcu_read_lock();
+ mpath = mesh_path_lookup(orig_addr, sdata);
+ if (!mpath) {
+ mesh_path_add(orig_addr, sdata);
+ mpath = mesh_path_lookup(orig_addr, sdata);
+ if (!mpath) {
+ rcu_read_unlock();
+ sdata->u.mesh.mshstats.dropped_frames_no_route++;
+ return;
+ }
+ mesh_queue_preq(mpath,
+ PREQ_Q_F_START | PREQ_Q_F_REFRESH);
+ }
+ if (mpath->dsn < orig_dsn) {
+ mesh_path_sel_frame_tx(MPATH_RANN, flags, orig_addr,
+ cpu_to_le32(orig_dsn),
+ 0, NULL, 0, sdata->dev->broadcast,
+ hopcount, ttl, 0, cpu_to_le32(metric),
+ 0, sdata);
+ mpath->dsn = orig_dsn;
+ }
+ rcu_read_unlock();
+}
void mesh_rx_path_sel_frame(struct ieee80211_sub_if_data *sdata,
@@ -654,7 +716,8 @@
return;
hwmp_perr_frame_process(sdata, mgmt, elems.perr);
}
-
+ if (elems.rann)
+ hwmp_rann_frame_process(sdata, mgmt, elems.rann);
}
/**
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index aedbaaa..da86e15 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -685,6 +685,10 @@
elems->perr = pos;
elems->perr_len = elen;
break;
+ case WLAN_EID_RANN:
+ if (elen >= sizeof(struct ieee80211_rann_ie))
+ elems->rann = (void *)pos;
+ break;
case WLAN_EID_CHANNEL_SWITCH:
elems->ch_switch_elem = pos;
elems->ch_switch_elem_len = elen;