From 19f10c785b2cc483c5c71169abb7e99b39c181aa Mon Sep 17 00:00:00 2001
From: Rui Paulo <rpaulo@FreeBSD.org>
Date: Sun, 21 Mar 2010 16:10:11 +0000
Subject: [PATCH] Implement bpf_track and iflladdr event handlers and activate
 the net80211 code to use them. This makes raw packet capturing work.

---
 sys/net/bpf.c                                  | 5 +++++
 sys/net/if.c                                   | 4 +++-
 sys/net/if_var.h                               | 4 ++++
 sys/netproto/802_11/wlan/ieee80211_dragonfly.c | 6 +-----
 sys/sys/eventhandler.h                         | 6 ++++++
 5 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/sys/net/bpf.c b/sys/net/bpf.c
index 1a69b1e037..b7b2f1dd7d 100644
--- a/sys/net/bpf.c
+++ b/sys/net/bpf.c
@@ -265,6 +265,8 @@ bpf_attachd(struct bpf_d *d, struct bpf_if *bp)
 	d->bd_bif = bp;
 	SLIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next);
 	*bp->bif_driverp = bp;
+
+	EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1);
 }
 
 /*
@@ -290,6 +292,9 @@ bpf_detachd(struct bpf_d *d)
 		*bp->bif_driverp = NULL;
 	}
 	d->bd_bif = NULL;
+
+	EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0);
+
 	/*
 	 * Check if this descriptor had requested promiscuous mode.
 	 * If so, turn it off.
diff --git a/sys/net/if.c b/sys/net/if.c
index 4186d2f158..47c9dc42d1 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1551,8 +1551,10 @@ ifioctl(struct socket *so, u_long cmd, caddr_t data, struct ucred *cred)
 		error = priv_check_cred(cred, PRIV_ROOT, 0);
 		if (error)
 			return (error);
-		return if_setlladdr(ifp,
+		error = if_setlladdr(ifp,
 		    ifr->ifr_addr.sa_data, ifr->ifr_addr.sa_len);
+		EVENTHANDLER_INVOKE(iflladdr_event, ifp);
+		return (error);
 
 	default:
 		oif_flags = ifp->if_flags;
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 0d2f1996ba..40a78cb6aa 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -354,6 +354,10 @@ typedef void if_init_f_t (void *);
 
 #ifdef _KERNEL
 
+/* interface link layer address change event */
+typedef void (*iflladdr_event_handler_t)(void *, struct ifnet *);
+EVENTHANDLER_DECLARE(iflladdr_event, iflladdr_event_handler_t);
+
 #ifdef INVARIANTS
 #define ASSERT_IFNET_SERIALIZED_ALL(ifp) \
 	(ifp)->if_serialize_assert((ifp), IFNET_SERIALIZE_ALL, TRUE)
diff --git a/sys/netproto/802_11/wlan/ieee80211_dragonfly.c b/sys/netproto/802_11/wlan/ieee80211_dragonfly.c
index 93cbb7f2c4..8288d07509 100644
--- a/sys/netproto/802_11/wlan/ieee80211_dragonfly.c
+++ b/sys/netproto/802_11/wlan/ieee80211_dragonfly.c
@@ -838,9 +838,7 @@ bpf_track(void *arg, struct ifnet *ifp, int dlt, int attach)
 {
 	/* NB: identify vap's by if_start */
 	if (dlt == DLT_IEEE802_11_RADIO && ifp->if_start == ieee80211_start) {
-#ifdef notyet
 		struct ieee80211vap *vap = ifp->if_softc;
-#endif
 		/*
 		 * Track bpf radiotap listener state.  We mark the vap
 		 * to indicate if any listener is present and the com
@@ -848,17 +846,15 @@ bpf_track(void *arg, struct ifnet *ifp, int dlt, int attach)
 		 * vap.  This flag is used by drivers to prepare radiotap
 		 * state only when needed.
 		 */
-#ifdef notyet
 		if (attach) {
 			ieee80211_syncflag_ext(vap, IEEE80211_FEXT_BPF);
 			if (vap->iv_opmode == IEEE80211_M_MONITOR)
 				atomic_add_int(&vap->iv_ic->ic_montaps, 1);
-		} else if (!bpf_peers_present(vap->iv_rawbpf)) {
+		} else if (!vap->iv_rawbpf) {
 			ieee80211_syncflag_ext(vap, -IEEE80211_FEXT_BPF);
 			if (vap->iv_opmode == IEEE80211_M_MONITOR)
 				atomic_subtract_int(&vap->iv_ic->ic_montaps, 1);
 		}
-#endif
 	}
 }
 
diff --git a/sys/sys/eventhandler.h b/sys/sys/eventhandler.h
index 5df59b8055..c334310f74 100644
--- a/sys/sys/eventhandler.h
+++ b/sys/sys/eventhandler.h
@@ -158,6 +158,12 @@ extern struct eventhandler_list	*eventhandler_find_list(char *name);
 #define	EVENTHANDLER_PRI_ANY	10000
 #define	EVENTHANDLER_PRI_LAST	20000
 
+/* BPF attach/detach events */
+struct ifnet;
+typedef void (*bpf_track_fn)(void *, struct ifnet *, int /* dlt */,
+    int /* 1 =>'s attach */);
+EVENTHANDLER_DECLARE(bpf_track, bpf_track_fn);
+
 struct image_params;
 struct proc;
 
-- 
2.41.0