Implementation of the upcoming Wireless Mesh standard, 802.11s, on the

net80211 wireless stack. This work is based on the March 2009 D3.0 draft
standard. This standard is expected to become final next year.
This includes two main net80211 modules, ieee80211_mesh.c
which deals with peer link management, link metric calculation,
routing table control and mesh configuration and ieee80211_hwmp.c
which deals with the actually routing process on the mesh network.
HWMP is the mandatory routing protocol on by the mesh standard, but
others, such as RA-OLSR, can be implemented.

Authentication and encryption are not implemented.

There are several scripts under tools/tools/net80211/scripts that can be
used to test different mesh network topologies and they also teach you
how to setup a mesh vap (for the impatient: ifconfig wlan0 create
wlandev ... wlanmode mesh).

A new build option is available: IEEE80211_SUPPORT_MESH and it's enabled
by default on GENERIC kernels for i386, amd64, sparc64 and pc98.

Drivers that support mesh networks right now are: ath, ral and mwl.

More information at: http://wiki.freebsd.org/WifiMesh

Please note that this work is experimental. Also, please note that
bridging a mesh vap with another network interface is not yet supported.

Many thanks to the FreeBSD Foundation for sponsoring this project and to
Sam Leffler for his support.
Also, I would like to thank Gateworks Corporation for sending me a
Cambria board which was used during the development of this project.

Reviewed by:	sam
Approved by:	re (kensmith)
Obtained from:	projects/mesh11s

1 files changed, 159 insertions, 25 deletions

diff --git a/sys/net80211/ieee80211_scan_sta.c b/sys/net80211/ieee80211_scan_sta.c
index 367ecce..a76dd3c 100644
--- a/sys/net80211/ieee80211_scan_sta.c
+++ b/sys/net80211/ieee80211_scan_sta.c
@@ -48,6 +48,9 @@ __FBSDID("$FreeBSD$");
 #ifdef IEEE80211_SUPPORT_TDMA
 #include <net80211/ieee80211_tdma.h>
 #endif
+#ifdef IEEE80211_SUPPORT_MESH
+#include <net80211/ieee80211_mesh.h>
+#endif
 
 #include <net/bpf.h>
 
@@ -112,21 +115,23 @@ static void sta_flush_table(struct sta_table *);
  * contents explains why.  The following flags are or'd to to this
  * mask and can be used to figure out why the entry was rejected.
  */
-#define	MATCH_CHANNEL		0x0001	/* channel mismatch */
-#define	MATCH_CAPINFO		0x0002	/* capabilities mismatch, e.g. no ess */
-#define	MATCH_PRIVACY		0x0004	/* privacy mismatch */
-#define	MATCH_RATE		0x0008	/* rate set mismatch */
-#define	MATCH_SSID		0x0010	/* ssid mismatch */
-#define	MATCH_BSSID		0x0020	/* bssid mismatch */
-#define	MATCH_FAILS		0x0040	/* too many failed auth attempts */
-#define	MATCH_NOTSEEN		0x0080	/* not seen in recent scans */
-#define	MATCH_RSSI		0x0100	/* rssi deemed too low to use */
-#define	MATCH_CC		0x0200	/* country code mismatch */
-#define	MATCH_TDMA_NOIE		0x0400	/* no TDMA ie */
-#define	MATCH_TDMA_NOTMASTER	0x0800	/* not TDMA master */
-#define	MATCH_TDMA_NOSLOT	0x1000	/* all TDMA slots occupied */
-#define	MATCH_TDMA_LOCAL	0x2000	/* local address */
-#define	MATCH_TDMA_VERSION	0x4000	/* protocol version mismatch */
+#define	MATCH_CHANNEL		0x00001	/* channel mismatch */
+#define	MATCH_CAPINFO		0x00002	/* capabilities mismatch, e.g. no ess */
+#define	MATCH_PRIVACY		0x00004	/* privacy mismatch */
+#define	MATCH_RATE		0x00008	/* rate set mismatch */
+#define	MATCH_SSID		0x00010	/* ssid mismatch */
+#define	MATCH_BSSID		0x00020	/* bssid mismatch */
+#define	MATCH_FAILS		0x00040	/* too many failed auth attempts */
+#define	MATCH_NOTSEEN		0x00080	/* not seen in recent scans */
+#define	MATCH_RSSI		0x00100	/* rssi deemed too low to use */
+#define	MATCH_CC		0x00200	/* country code mismatch */
+#define	MATCH_TDMA_NOIE		0x00400	/* no TDMA ie */
+#define	MATCH_TDMA_NOTMASTER	0x00800	/* not TDMA master */
+#define	MATCH_TDMA_NOSLOT	0x01000	/* all TDMA slots occupied */
+#define	MATCH_TDMA_LOCAL	0x02000	/* local address */
+#define	MATCH_TDMA_VERSION	0x04000	/* protocol version mismatch */
+#define	MATCH_MESH_NOID		0x10000	/* no MESHID ie */
+#define	MATCH_MESHID		0x20000	/* meshid mismatch */
 static int match_bss(struct ieee80211vap *,
 	const struct ieee80211_scan_state *, struct sta_entry *, int);
 static void adhoc_age(struct ieee80211_scan_state *);
@@ -139,6 +144,10 @@ isocmp(const uint8_t cc1[], const uint8_t cc2[])
 
 /* number of references from net80211 layer */
 static	int nrefs = 0;
+/*
+ * Module glue.
+ */
+IEEE80211_SCANNER_MODULE(sta, 1);
 
 /*
  * Attach prior to any scanning work.
@@ -281,6 +290,10 @@ found:
 	memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp));
 	ise->se_intval = sp->bintval;
 	ise->se_capinfo = sp->capinfo;
+#ifdef IEEE80211_SUPPORT_MESH
+	if (sp->meshid != NULL && sp->meshid[1] != 0)
+		memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]);
+#endif
 	/*
 	 * Beware of overriding se_chan for frames seen
 	 * off-channel; this can cause us to attempt an
@@ -895,6 +908,12 @@ back:
 #undef RV
 }
 
+static __inline int
+match_id(const uint8_t *ie, const uint8_t *val, int len)
+{
+	return (ie[1] == len && memcmp(ie+2, val, len) == 0);
+}
+
 static int
 match_ssid(const uint8_t *ie,
 	int nssid, const struct ieee80211_scan_ssid ssids[])
@@ -902,8 +921,7 @@ match_ssid(const uint8_t *ie,
 	int i;
 
 	for (i = 0; i < nssid; i++) {
-		if (ie[1] == ssids[i].len &&
-		     memcmp(ie+2, ssids[i].ssid, ie[1]) == 0)
+		if (match_id(ie, ssids[i].ssid, ssids[i].len))
 			return 1;
 	}
 	return 0;
@@ -986,7 +1004,22 @@ match_bss(struct ieee80211vap *vap,
 #endif
 		}
 #endif /* IEEE80211_SUPPORT_TDMA */
+#ifdef IEEE80211_SUPPORT_MESH
+	} else if (vap->iv_opmode == IEEE80211_M_MBSS) {
+		const struct ieee80211_mesh_state *ms = vap->iv_mesh;
+		/*
+		 * Mesh nodes have IBSS & ESS bits in capinfo turned off
+		 * and two special ie's that must be present.
+		 */
+		if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS))
+			fail |= MATCH_CAPINFO;
+		else if (se->se_meshid == NULL)
+			fail |= MATCH_MESH_NOID;
+		else if (ms->ms_idlen != 0 &&
+		    match_id(se->se_meshid, ms->ms_id, ms->ms_idlen))
+			fail |= MATCH_MESHID;
 	} else {
+#endif
 		if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0)
 			fail |= MATCH_CAPINFO;
 		/*
@@ -1070,6 +1103,7 @@ match_bss(struct ieee80211vap *vap,
 		    fail & MATCH_TDMA_NOSLOT ? 'f' :
 		    fail & MATCH_TDMA_LOCAL ? 'l' :
 #endif
+		    fail & MATCH_MESH_NOID ? 'm' :
 		    fail ? '-' : '+', ether_sprintf(se->se_macaddr));
 		printf(" %s%c", ether_sprintf(se->se_bssid),
 		    fail & MATCH_BSSID ? '!' : ' ');
@@ -1087,7 +1121,7 @@ match_bss(struct ieee80211vap *vap,
 		    "wep" : "no",
 		    fail & MATCH_PRIVACY ? '!' : ' ');
 		ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]);
-		printf("%s\n", fail & MATCH_SSID ? "!" : "");
+		printf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : "");
 	}
 #endif
 	return fail;
@@ -1415,6 +1449,7 @@ static const struct ieee80211_scanner sta_default = {
 	.scan_assoc_fail	= sta_assoc_fail,
 	.scan_assoc_success	= sta_assoc_success,
 };
+IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default);
 
 /*
  * Adhoc mode-specific support.
@@ -1514,7 +1549,8 @@ adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
 	struct ieee80211_channel *chan;
 
 	KASSERT(vap->iv_opmode == IEEE80211_M_IBSS ||
-		vap->iv_opmode == IEEE80211_M_AHDEMO,
+		vap->iv_opmode == IEEE80211_M_AHDEMO ||
+		vap->iv_opmode == IEEE80211_M_MBSS,
 		("wrong opmode %u", vap->iv_opmode));
 
 	if (st->st_newscan) {
@@ -1630,6 +1666,8 @@ static const struct ieee80211_scanner adhoc_default = {
 	.scan_assoc_fail	= sta_assoc_fail,
 	.scan_assoc_success	= sta_assoc_success,
 };
+IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default);
+IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default);
 
 static void
 ap_force_promisc(struct ieee80211com *ic)
@@ -1781,12 +1819,108 @@ static const struct ieee80211_scanner ap_default = {
 	.scan_assoc_success	= sta_assoc_success,
 	.scan_assoc_fail	= sta_assoc_fail,
 };
+IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default);
 
+#ifdef IEEE80211_SUPPORT_MESH
 /*
- * Module glue.
+ * Pick an mbss network to join or find a channel
+ * to use to start an mbss network.
  */
-IEEE80211_SCANNER_MODULE(sta, 1);
-IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default);
-IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default);
-IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default);
-IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default);
+static int
+mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
+{
+	struct sta_table *st = ss->ss_priv;
+	struct ieee80211_mesh_state *ms = vap->iv_mesh;
+	struct sta_entry *selbs;
+	struct ieee80211_channel *chan;
+
+	KASSERT(vap->iv_opmode == IEEE80211_M_MBSS,
+		("wrong opmode %u", vap->iv_opmode));
+
+	if (st->st_newscan) {
+		sta_update_notseen(st);
+		st->st_newscan = 0;
+	}
+	if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
+		/*
+		 * Manual/background scan, don't select+join the
+		 * bss, just return.  The scanning framework will
+		 * handle notification that this has completed.
+		 */
+		ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
+		return 1;
+	}
+	/*
+	 * Automatic sequencing; look for a candidate and
+	 * if found join the network.
+	 */
+	/* NB: unlocked read should be ok */
+	if (TAILQ_FIRST(&st->st_entry) == NULL) {
+		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
+			"%s: no scan candidate\n", __func__);
+		if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
+			return 0;
+notfound:
+		if (ms->ms_idlen != 0) {
+			/*
+			 * No existing mbss network to join and we have
+			 * a meshid; start one up.  If no channel was
+			 * specified, try to select a channel.
+			 */
+			if (vap->iv_des_chan == IEEE80211_CHAN_ANYC ||
+			    IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
+				struct ieee80211com *ic = vap->iv_ic;
+
+				chan = adhoc_pick_channel(ss, 0);
+				if (chan != NULL)
+					chan = ieee80211_ht_adjust_channel(ic,
+					    chan, vap->iv_flags_ht);
+			} else
+				chan = vap->iv_des_chan;
+			if (chan != NULL) {
+				ieee80211_create_ibss(vap, chan);
+				return 1;
+			}
+		}
+		/*
+		 * If nothing suitable was found decrement
+		 * the failure counts so entries will be
+		 * reconsidered the next time around.  We
+		 * really want to do this only for sta's
+		 * where we've previously had some success.
+		 */
+		sta_dec_fails(st);
+		st->st_newscan = 1;
+		return 0;			/* restart scan */
+	}
+	selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
+	if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
+		return (selbs != NULL);
+	if (selbs == NULL)
+		goto notfound;
+	chan = selbs->base.se_chan;
+	if (selbs->se_flags & STA_DEMOTE11B)
+		chan = demote11b(vap, chan);
+	if (!ieee80211_sta_join(vap, chan, &selbs->base))
+		goto notfound;
+	return 1;				/* terminate scan */
+}
+
+static const struct ieee80211_scanner mesh_default = {
+	.scan_name		= "default",
+	.scan_attach		= sta_attach,
+	.scan_detach		= sta_detach,
+	.scan_start		= adhoc_start,
+	.scan_restart		= sta_restart,
+	.scan_cancel		= sta_cancel,
+	.scan_end		= mesh_pick_bss,
+	.scan_flush		= sta_flush,
+	.scan_pickchan		= adhoc_pick_channel,
+	.scan_add		= sta_add,
+	.scan_age		= adhoc_age,
+	.scan_iterate		= sta_iterate,
+	.scan_assoc_fail	= sta_assoc_fail,
+	.scan_assoc_success	= sta_assoc_success,
+};
+IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default);
+#endif /* IEEE80211_SUPPORT_MESH */