send raw 802.11 frames with bpf(4) using the IEEE802_11 or

IEEE802_11_RADIO data link types.

ok canacar@ damien@

4 files changed, 134 insertions, 4 deletions

diff --git a/sys/net/bpf.c b/sys/net/bpf.c
index 8588e507fa8..980066a9490 100644
--- a/sys/net/bpf.c
+++ b/sys/net/bpf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bpf.c,v 1.57 2005/04/20 17:03:22 reyk Exp $	*/
+/*	$OpenBSD: bpf.c,v 1.58 2005/04/20 19:52:42 reyk Exp $	*/
 /*	$NetBSD: bpf.c,v 1.33 1997/02/21 23:59:35 thorpej Exp $	*/
 
 /*
@@ -107,6 +107,7 @@ bpf_movein(struct uio *uio, u_int linktype, struct mbuf **mp,
     struct sockaddr *sockp, struct bpf_insn *filter)
 {
 	struct mbuf *m;
+	struct m_tag *mtag;
 	int error;
 	u_int hlen;
 	u_int len;
@@ -150,6 +151,12 @@ bpf_movein(struct uio *uio, u_int linktype, struct mbuf **mp,
 		hlen = 24;
 		break;
 
+	case DLT_IEEE802_11:
+	case DLT_IEEE802_11_RADIO:
+		sockp->sa_family = AF_UNSPEC;
+		hlen = 0;
+		break;
+
 	case DLT_RAW:
 	case DLT_NULL:
 		sockp->sa_family = AF_UNSPEC;
@@ -211,6 +218,15 @@ bpf_movein(struct uio *uio, u_int linktype, struct mbuf **mp,
 		m->m_data += hlen; /* XXX */
 	}
 
+	/*
+	 * Prepend the data link type as a mbuf tag
+	 */
+	mtag = m_tag_get(PACKET_TAG_DLT, sizeof(u_int), M_NOWAIT);
+	if (mtag == NULL)
+		return (ENOMEM);
+	*(u_int *)(mtag + 1) = linktype;
+	m_tag_prepend(m, mtag);
+
 	return (0);
  bad:
 	m_freem(m);
diff --git a/sys/net80211/ieee80211.c b/sys/net80211/ieee80211.c
index 20af2f2d2ea..ab2c5a3b9bd 100644
--- a/sys/net80211/ieee80211.c
+++ b/sys/net80211/ieee80211.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211.c,v 1.4 2005/02/17 18:28:05 reyk Exp $	*/
+/*	$OpenBSD: ieee80211.c,v 1.5 2005/04/20 19:52:43 reyk Exp $	*/
 /*	$NetBSD: ieee80211.c,v 1.19 2004/06/06 05:45:29 dyoung Exp $	*/
 
 /*-
@@ -155,6 +155,9 @@ ieee80211_ifattach(struct ifnet *ifp)
 #else
 	ether_ifattach(ifp, ic->ic_myaddr);
 #endif
+
+	ifp->if_output = ieee80211_output;
+
 #if NBPFILTER > 0
 	BPF_ATTACH(ifp, DLT_IEEE802_11,
 	    sizeof(struct ieee80211_frame_addr4), &ic->ic_rawbpf);
diff --git a/sys/net80211/ieee80211_output.c b/sys/net80211/ieee80211_output.c
index 8818c0db755..c104fe472b0 100644
--- a/sys/net80211/ieee80211_output.c
+++ b/sys/net80211/ieee80211_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_output.c,v 1.8 2005/03/11 23:20:26 jsg Exp $	*/
+/*	$OpenBSD: ieee80211_output.c,v 1.9 2005/04/20 19:52:43 reyk Exp $	*/
 /*	$NetBSD: ieee80211_output.c,v 1.13 2004/05/31 11:02:55 dyoung Exp $	*/
 
 /*-
@@ -92,6 +92,67 @@ __KERNEL_RCSID(0, "$NetBSD: ieee80211_output.c,v 1.13 2004/05/31 11:02:55 dyoung
 #include <net80211/ieee80211_compat.h>
 
 /*
+ * IEEE 802.11 output routine. Normally this will directly call the
+ * Ethernet output routine because 802.11 encapsulation is called
+ * later by the driver. This function could be used to send raw frames
+ * if the mbuf has been tagged with a 802.11 data link type.
+ */
+int
+ieee80211_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+    struct rtentry *rt)
+{
+	u_int dlt = 0;
+	int s, error = 0;
+	struct m_tag *mtag;
+	
+	/* Interface has to be up and running */
+	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
+	    (IFF_UP | IFF_RUNNING)) {
+		error = ENETDOWN;
+		goto bad;
+	}
+
+	/* Try to get the DLT from a mbuf tag */
+	if ((mtag = m_tag_find(m, PACKET_TAG_DLT, NULL)) != NULL) {
+		dlt = *(u_int *)(mtag + 1);
+
+		/* Fallback to ethernet for non-802.11 linktypes */
+		if (!(dlt == DLT_IEEE802_11 || dlt == DLT_IEEE802_11_RADIO))
+			goto fallback;
+
+		/*
+		 * Queue message on interface without adding any
+		 * further headers, and start output if interface not
+		 * yet active.
+		 */
+		s = splimp();
+		IFQ_ENQUEUE(&ifp->if_snd, m, NULL, error);
+		if (error) {
+			/* mbuf is already freed */
+			splx(s);
+			if_printf(ifp, "failed to queue raw tx frame\n");
+			return (error);
+		}
+		ifp->if_obytes += m->m_pkthdr.len;
+		if (m->m_flags & M_MCAST)
+			ifp->if_omcasts++;
+		if ((ifp->if_flags & IFF_OACTIVE) == 0)
+			(*ifp->if_start)(ifp);
+		splx(s);
+
+		return (error);
+	}
+
+ fallback:
+	return (ether_output(ifp, m, dst, rt));
+
+ bad:
+	if (m)
+		m_freem(m);
+	return (error);
+}
+
+/*
  * Send a management frame to the specified node.  The node pointer
  * must have a reference as the pointer will be passed to the driver
  * and potentially held for a long time.  If the frame is successfully
@@ -185,7 +246,55 @@ ieee80211_encap(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node **pni)
 	struct ieee80211_frame *wh;
 	struct ieee80211_node *ni = NULL;
 	struct llc *llc;
+	struct m_tag *mtag;
+	u_int8_t *addr;
+	u_int dlt;
+
+	/* Handle raw frames if mbuf is tagged as 802.11 */
+	if ((mtag = m_tag_find(m, PACKET_TAG_DLT, NULL)) != NULL) {
+		dlt = *(u_int *)(mtag + 1);
+		
+		if (!(dlt == DLT_IEEE802_11 || dlt == DLT_IEEE802_11_RADIO))
+			goto fallback;
+		
+		wh = mtod(m, struct ieee80211_frame *);
+
+		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min))
+			goto bad;
+
+		if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
+		    IEEE80211_FC0_VERSION_0)
+			goto bad;
+
+		switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
+		case IEEE80211_FC1_DIR_NODS:
+		case IEEE80211_FC1_DIR_FROMDS:
+			addr = wh->i_addr1;
+			break;
+		case IEEE80211_FC1_DIR_DSTODS:
+		case IEEE80211_FC1_DIR_TODS:
+			addr = wh->i_addr3;
+			break;
+		default:
+			goto bad;
+		}
+
+		ni = ieee80211_find_txnode(ic, addr);
+		if (ni == NULL)
+			ni = ieee80211_ref_node(ic->ic_bss);
+		if (ni == NULL) {
+			if_printf(ifp, "no node for dst %s, "
+			    "discard raw tx frame\n", ether_sprintf(addr));
+			ic->ic_stats.is_tx_nonode++;
+			goto bad;
+		}
+		ni->ni_inact = 0;
+
+		*pni = ni;
+		return (m);
+	}
 
+ fallback:
 	if (m->m_len < sizeof(struct ether_header)) {
 		m = m_pullup(m, sizeof(struct ether_header));
 		if (m == NULL) {
diff --git a/sys/net80211/ieee80211_proto.h b/sys/net80211/ieee80211_proto.h
index 0a59806594e..670d8019f38 100644
--- a/sys/net80211/ieee80211_proto.h
+++ b/sys/net80211/ieee80211_proto.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ieee80211_proto.h,v 1.6 2005/03/03 14:36:41 damien Exp $	*/
+/*	$OpenBSD: ieee80211_proto.h,v 1.7 2005/04/20 19:52:43 reyk Exp $	*/
 /*	$NetBSD: ieee80211_proto.h,v 1.3 2003/10/13 04:23:56 dyoung Exp $	*/
 
 /*-
@@ -61,6 +61,8 @@ extern	void ieee80211_proto_detach(struct ifnet *);
 struct ieee80211_node;
 extern	void ieee80211_input(struct ifnet *, struct mbuf *,
 		struct ieee80211_node *, int, u_int32_t);
+extern	int ieee80211_output(struct ifnet *, struct mbuf *, struct sockaddr *,
+		struct rtentry *);
 extern	void ieee80211_recv_mgmt(struct ieee80211com *, struct mbuf *,
 		struct ieee80211_node *, int, int, u_int32_t);
 extern	int ieee80211_send_mgmt(struct ieee80211com *, struct ieee80211_node *,