From 5be9a825e285a775406a93f6ca2c342d8c17655c Mon Sep 17 00:00:00 2001
From: Hartmut Brandt <harti@FreeBSD.org>
Date: Thu, 24 Jul 2003 08:15:20 +0000
Subject: [PATCH] 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
---
 sys/netatm/atm_cm.c     | 12 ++++++++++++
 sys/netatm/atm_device.c | 12 ++++++++++++
 sys/netatm/atm_if.c     | 13 +++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/sys/netatm/atm_cm.c b/sys/netatm/atm_cm.c
index 8ca491fbeded..f21db37214ba 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>
@@ -2899,6 +2900,17 @@ atm_cm_cpcs_upper(cmd, tok, arg1, arg2)
 			break;
 
 		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
 			 */
diff --git a/sys/netatm/atm_device.c b/sys/netatm/atm_device.c
index d3bc45bc61c5..cbfdaa6c8c7d 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>
@@ -370,6 +371,17 @@ atm_dev_lower(cmd, tok, arg1, arg2)
 			break;
 		}
 
+		/*
+		 * 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
 		 */
diff --git a/sys/netatm/atm_if.c b/sys/netatm/atm_if.c
index cc0b657f56b5..52e236282900 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>
@@ -776,6 +777,13 @@ 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
 	 */
@@ -838,6 +846,11 @@ atm_nif_detach(nip)
 		(void) (*ncp->ncm_stat)(NCM_DETACH, nip, 0);
 	}
 
+	/*
+	 * Remove from BPF interface list
+	 */
+	bpfdetach(ifp);
+
 	/*
 	 * Mark interface down
 	 */