Add BPF support to HARP network interfaces. This allows one to see

the traffic on LLC multiplexed connections (like CLIP).

PR:		kern/51831
Submitted by:	Vincent Jardin <vjardin@wanadoo.fr>
MFC after:	2 weeks

3 files changed, 37 insertions, 0 deletions

diff --git a/sys/netatm/atm_cm.c b/sys/netatm/atm_cm.c
index 8ca491f..f21db37 100644
--- a/sys/netatm/atm_cm.c
+++ b/sys/netatm/atm_cm.c
@@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/socketvar.h>
 #include <sys/syslog.h>
 #include <net/if.h>
+#include <net/bpf.h>
 #include <netatm/port.h>
 #include <netatm/queue.h>
 #include <netatm/atm.h>
@@ -2900,6 +2901,17 @@ atm_cm_cpcs_upper(cmd, tok, arg1, arg2)
 
 		case ATM_ENC_LLC:
 			/*
+			 * Send the packet to the interface's bpf if this
+			 * vc has one.
+			 */
+			if (cvp->cvc_vcc != NULL &&
+			    cvp->cvc_vcc->vc_nif != NULL) {
+				struct ifnet *ifp =
+				    (struct ifnet *)cvp->cvc_vcc->vc_nif;
+
+				BPF_MTAP(ifp, m);
+			}
+			/*
 			 * Find connection with matching LLC header
 			 */
 			if (KB_LEN(m) < T_ATM_LLC_MAX_LEN) {
diff --git a/sys/netatm/atm_device.c b/sys/netatm/atm_device.c
index d3bc45b..cbfdaa6 100644
--- a/sys/netatm/atm_device.c
+++ b/sys/netatm/atm_device.c
@@ -42,6 +42,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/socketvar.h>
 #include <sys/syslog.h>
 #include <net/if.h>
+#include <net/bpf.h>
 #include <netatm/port.h>
 #include <netatm/queue.h>
 #include <netatm/atm.h>
@@ -371,6 +372,17 @@ atm_dev_lower(cmd, tok, arg1, arg2)
 		}
 
 		/*
+		 * Send the packet to the interface's bpf if this vc has one.
+		 */
+		if (cvcp->cvc_conn->co_mpx == ATM_ENC_LLC &&
+		    cvcp->cvc_vcc && cvcp->cvc_vcc->vc_nif) {
+			struct ifnet *ifp =
+			    (struct ifnet *)cvcp->cvc_vcc->vc_nif;
+
+			BPF_MTAP(ifp, (KBuffer *)arg1);
+		}
+
+		/*
 		 * Hand the data off to the device
 		 */
 		(*cup->cu_output)(cup, cvp, (KBuffer *)arg1);
diff --git a/sys/netatm/atm_if.c b/sys/netatm/atm_if.c
index cc0b657..52e2362 100644
--- a/sys/netatm/atm_if.c
+++ b/sys/netatm/atm_if.c
@@ -44,6 +44,7 @@ __FBSDID("$FreeBSD$");
 #include <net/if_types.h>
 #include <net/if_dl.h>
 #include <net/route.h>
+#include <net/bpf.h>
 #include <netinet/in.h>
 #include <netinet/in_var.h>
 #include <netatm/port.h>
@@ -777,6 +778,13 @@ atm_nif_attach(nip)
 	if_attach(ifp);
 
 	/*
+	 * Add to BPF interface list
+	 * DLT_ATM_RFC_1483 cannot be used because both NULL and LLC/SNAP could
+	 * be provisioned
+	 */
+	bpfattach(ifp, DLT_ATM_CLIP, T_ATM_LLC_MAX_LEN);
+
+	/*
 	 * Add to physical interface list
 	 */
 	LINK2TAIL(nip, struct atm_nif, pip->pif_nif, nif_pnext);
@@ -839,6 +847,11 @@ atm_nif_detach(nip)
 	}
 
 	/*
+	 * Remove from BPF interface list
+	 */
+	bpfdetach(ifp);
+
+	/*
 	 * Mark interface down
 	 */
 	if_down(ifp);