Update 802.11 wireless support:

o major overhaul of the way channels are handled: channels are now
  fully enumerated and uniquely identify the operating characteristics;
  these changes are visible to user applications which require changes
o make scanning support independent of the state machine to enable
  background scanning and roaming
o move scanning support into loadable modules based on the operating
  mode to enable different policies and reduce the memory footprint
  on systems w/ constrained resources
o add background scanning in station mode (no support for adhoc/ibss
  mode yet)
o significantly speedup sta mode scanning with a variety of techniques
o add roaming support when background scanning is supported; for now
  we use a simple algorithm to trigger a roam: we threshold the rssi
  and tx rate, if either drops too low we try to roam to a new ap
o add tx fragmentation support
o add first cut at 802.11n support: this code works with forthcoming
  drivers but is incomplete; it's included now to establish a baseline
  for other drivers to be developed and for user applications
o adjust max_linkhdr et. al. to reflect 802.11 requirements; this eliminates
  prepending mbufs for traffic generated locally
o add support for Atheros protocol extensions; mainly the fast frames
  encapsulation (note this can be used with any card that can tx+rx
  large frames correctly)
o add sta support for ap's that beacon both WPA1+2 support
o change all data types from bsd-style to posix-style
o propagate noise floor data from drivers to net80211 and on to user apps
o correct various issues in the sta mode state machine related to handling
  authentication and association failures
o enable the addition of sta mode power save support for drivers that need
  net80211 support (not in this commit)
o remove old WI compatibility ioctls (wicontrol is officially dead)
o change the data structures returned for get sta info and get scan
  results so future additions will not break user apps
o fixed tx rate is now maintained internally as an ieee rate and not an
  index into the rate set; this needs to be extended to deal with
  multi-mode operation
o add extended channel specifications to radiotap to enable 11n sniffing

Drivers:
o ath: add support for bg scanning, tx fragmentation, fast frames,
       dynamic turbo (lightly tested), 11n (sniffing only and needs
       new hal)
o awi: compile tested only
o ndis: lightly tested
o ipw: lightly tested
o iwi: add support for bg scanning (well tested but may have some
       rough edges)
o ral, ural, rum: add suppoort for bg scanning, calibrate rssi data
o wi: lightly tested

This work is based on contributions by Atheros, kmacy, sephe, thompsa,
mlaier, kevlo, and others.  Much of the scanning work was supported by
Atheros.  The 11n work was supported by Marvell.

1 files changed, 328 insertions, 0 deletions

diff --git a/sys/net80211/ieee80211_power.c b/sys/net80211/ieee80211_power.c
new file mode 100644
index 0000000..2064807
--- /dev/null
+++ b/sys/net80211/ieee80211_power.c
@@ -0,0 +1,328 @@
+/*-
+ * Copyright (c) 2002-2007 Sam Leffler, Errno Consulting
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * IEEE 802.11 power save support.
+ */
+#include <sys/param.h>
+#include <sys/systm.h> 
+#include <sys/kernel.h>
+ 
+#include <sys/socket.h>
+
+#include <net/if.h>
+#include <net/if_media.h>
+#include <net/ethernet.h>
+
+#include <net80211/ieee80211_var.h>
+
+#include <net/bpf.h>
+
+static void ieee80211_set_tim(struct ieee80211_node *ni, int set);
+
+void
+ieee80211_power_attach(struct ieee80211com *ic)
+{
+	if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
+	    ic->ic_opmode == IEEE80211_M_IBSS) {
+		/* NB: driver should override */
+		ic->ic_set_tim = ieee80211_set_tim;
+	}
+}
+
+void
+ieee80211_power_lateattach(struct ieee80211com *ic)
+{
+	/*
+	 * Allocate these only if needed.  Beware that we
+	 * know adhoc mode doesn't support ATIM yet...
+	 */
+	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
+		ic->ic_tim_len = howmany(ic->ic_max_aid,8) * sizeof(uint8_t);
+		MALLOC(ic->ic_tim_bitmap, uint8_t *, ic->ic_tim_len,
+			M_DEVBUF, M_NOWAIT | M_ZERO);
+		if (ic->ic_tim_bitmap == NULL) {
+			printf("%s: no memory for TIM bitmap!\n", __func__);
+			/* XXX good enough to keep from crashing? */
+			ic->ic_tim_len = 0;
+		}
+	}
+}
+
+void
+ieee80211_power_detach(struct ieee80211com *ic)
+{
+	if (ic->ic_tim_bitmap != NULL) {
+		FREE(ic->ic_tim_bitmap, M_DEVBUF);
+		ic->ic_tim_bitmap = NULL;
+	}
+}
+
+/*
+ * Clear any frames queued on a node's power save queue.
+ * The number of frames that were present is returned.
+ */
+int
+ieee80211_node_saveq_drain(struct ieee80211_node *ni)
+{
+	int qlen;
+
+	IEEE80211_NODE_SAVEQ_LOCK(ni);
+	qlen = IEEE80211_NODE_SAVEQ_QLEN(ni);
+	_IF_DRAIN(&ni->ni_savedq);
+	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+
+	return qlen;
+}
+
+/*
+ * Age frames on the power save queue. The aging interval is
+ * 4 times the listen interval specified by the station.  This
+ * number is factored into the age calculations when the frame
+ * is placed on the queue.  We store ages as time differences
+ * so we can check and/or adjust only the head of the list.
+ * If a frame's age exceeds the threshold then discard it.
+ * The number of frames discarded is returned so the caller
+ * can check if it needs to adjust the tim.
+ */
+int
+ieee80211_node_saveq_age(struct ieee80211_node *ni)
+{
+	int discard = 0;
+
+	if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
+		struct mbuf *m;
+
+		IEEE80211_NODE_SAVEQ_LOCK(ni);
+		while (IF_POLL(&ni->ni_savedq, m) != NULL &&
+		     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
+IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
+			_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
+			m_freem(m);
+			discard++;
+		}
+		if (m != NULL)
+			M_AGE_SUB(m, IEEE80211_INACT_WAIT);
+		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+
+		IEEE80211_NOTE(ni->ni_ic, IEEE80211_MSG_POWER, ni,
+		    "discard %u frames for age", discard);
+		IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard);
+	}
+	return discard;
+}
+
+/*
+ * Indicate whether there are frames queued for a station in power-save mode.
+ */
+static void
+ieee80211_set_tim(struct ieee80211_node *ni, int set)
+{
+	struct ieee80211com *ic = ni->ni_ic;
+	uint16_t aid;
+
+	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
+		ic->ic_opmode == IEEE80211_M_IBSS,
+		("operating mode %u", ic->ic_opmode));
+
+	aid = IEEE80211_AID(ni->ni_associd);
+	KASSERT(aid < ic->ic_max_aid,
+		("bogus aid %u, max %u", aid, ic->ic_max_aid));
+
+	IEEE80211_BEACON_LOCK(ic);
+	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
+		if (set) {
+			setbit(ic->ic_tim_bitmap, aid);
+			ic->ic_ps_pending++;
+		} else {
+			clrbit(ic->ic_tim_bitmap, aid);
+			ic->ic_ps_pending--;
+		}
+		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
+	}
+	IEEE80211_BEACON_UNLOCK(ic);
+}
+
+/*
+ * Save an outbound packet for a node in power-save sleep state.
+ * The new packet is placed on the node's saved queue, and the TIM
+ * is changed, if necessary.
+ */
+void
+ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m)
+{
+	struct ieee80211com *ic = ni->ni_ic;
+	int qlen, age;
+
+	IEEE80211_NODE_SAVEQ_LOCK(ni);
+	if (_IF_QFULL(&ni->ni_savedq)) {
+		_IF_DROP(&ni->ni_savedq);
+		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
+			"[%s] pwr save q overflow, drops %d (size %d)\n",
+			ether_sprintf(ni->ni_macaddr), 
+			ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE);
+#ifdef IEEE80211_DEBUG
+		if (ieee80211_msg_dumppkts(ic))
+			ieee80211_dump_pkt(ic, mtod(m, caddr_t), m->m_len, -1, -1);
+#endif
+		m_freem(m);
+		return;
+	}
+	/*
+	 * Tag the frame with it's expiry time and insert
+	 * it in the queue.  The aging interval is 4 times
+	 * the listen interval specified by the station. 
+	 * Frames that sit around too long are reclaimed
+	 * using this information.
+	 */
+	/* TU -> secs.  XXX handle overflow? */
+	age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000;
+	_IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age);
+	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+
+	IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
+		"[%s] save frame with age %d, %u now queued\n",
+		ether_sprintf(ni->ni_macaddr), age, qlen);
+
+	if (qlen == 1 && ic->ic_set_tim != NULL)
+		ic->ic_set_tim(ni, 1);
+}
+
+/*
+ * Handle station power-save state change.
+ */
+void
+ieee80211_node_pwrsave(struct ieee80211_node *ni, int enable)
+{
+	struct ieee80211com *ic = ni->ni_ic;
+	struct mbuf *m, *mhead, *mtail;
+	int mcount;
+
+	if (enable) {
+		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0)
+			ic->ic_ps_sta++;
+		ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
+		IEEE80211_NOTE(ic, IEEE80211_MSG_POWER, ni,
+		    "power save mode on, %u sta's in ps mode", ic->ic_ps_sta);
+		return;
+	}
+
+	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT)
+		ic->ic_ps_sta--;
+	ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
+	IEEE80211_NOTE(ic, IEEE80211_MSG_POWER, ni,
+	    "power save mode off, %u sta's in ps mode", ic->ic_ps_sta);
+	/* XXX if no stations in ps mode, flush mc frames */
+
+	/*
+	 * Flush queued unicast frames.
+	 */
+	if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0) {
+		if (ic->ic_set_tim != NULL)
+			ic->ic_set_tim(ni, 0);		/* just in case */
+		return;
+	}
+	IEEE80211_NOTE(ic, IEEE80211_MSG_POWER, ni,
+	    "flush ps queue, %u packets queue", IEEE80211_NODE_SAVEQ_QLEN(ni));
+	/*
+	 * Unload the frames from the ps q but don't send them
+	 * to the driver yet.  We do this in two stages to minimize
+	 * locking but also because there's no easy way to preserve
+	 * ordering given the existing ifnet access mechanisms.
+	 * XXX could be optimized
+	 */
+	IEEE80211_NODE_SAVEQ_LOCK(ni);
+	mcount = IEEE80211_NODE_SAVEQ_QLEN(ni);
+	mhead = mtail = NULL;
+	for (;;) {
+		_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
+		if (m == NULL)
+			break;
+		if (mhead == NULL) {
+			mhead = m;
+			m->m_nextpkt = NULL;
+		} else
+			mtail->m_nextpkt = m;
+		mtail = m;
+	}
+	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+	if (mhead != NULL) {
+		/* XXX need different driver interface */
+		/* XXX bypasses q max */
+		IF_PREPEND_LIST(&ic->ic_ifp->if_snd, mhead, mtail, mcount);
+	}
+	if (ic->ic_set_tim != NULL)
+		ic->ic_set_tim(ni, 0);
+}
+
+/*
+ * Handle power-save state change in station mode.
+ */
+void
+ieee80211_sta_pwrsave(struct ieee80211com *ic, int enable)
+{
+	struct ieee80211_node *ni = ic->ic_bss;
+	int qlen;
+
+	if (!((enable != 0) ^ ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) != 0)))
+		return;
+
+	IEEE80211_NOTE(ic, IEEE80211_MSG_POWER, ni,
+	    "sta power save mode %s", enable ? "on" : "off");
+	if (!enable) {
+		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
+		ieee80211_send_nulldata(ieee80211_ref_node(ni));
+		/*
+		 * Flush any queued frames; we can do this immediately
+		 * because we know they'll be queued behind the null
+		 * data frame we send the ap.
+		 * XXX can we use a data frame to take us out of ps?
+		 */
+		qlen = IEEE80211_NODE_SAVEQ_QLEN(ni);
+		if (qlen != 0) {
+			IEEE80211_NOTE(ic, IEEE80211_MSG_POWER, ni,
+			    "flush ps queue, %u packets queued", qlen);
+			for (;;) {
+				struct mbuf *m;
+
+				IEEE80211_NODE_SAVEQ_LOCK(ni);
+				_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
+				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
+				if (m == NULL)
+					break;
+				/* XXX need different driver interface */
+				/* XXX bypasses q max */
+				IF_ENQUEUE(&ic->ic_ifp->if_snd, m);
+			}
+		}
+	} else {
+		ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
+		ieee80211_send_nulldata(ieee80211_ref_node(ni));
+	}
+}