3 files changed, 23 insertions, 0 deletions

diff --git a/sys/net/if.c b/sys/net/if.c
index c08d494b9b63..edc73036f862 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -994,6 +994,11 @@ ifioctl(so, cmd, data, td)
 		ifr->ifr_flags = ifp->if_flags;
 		break;
 
+	case SIOCGIFCAP:
+		ifr->ifr_reqcap = ifp->if_capabilities;
+		ifr->ifr_curcap = ifp->if_capenable;
+		break;
+
 	case SIOCGIFMETRIC:
 		ifr->ifr_metric = ifp->if_metric;
 		break;
@@ -1031,6 +1036,15 @@ ifioctl(so, cmd, data, td)
 		getmicrotime(&ifp->if_lastchange);
 		break;
 
+	case SIOCSIFCAP:
+		error = suser_td(td);
+		if (error)
+			return (error);
+		if (ifr->ifr_reqcap & ~ifp->if_capabilities)
+			return (EINVAL);
+		(void) (*ifp->if_ioctl)(ifp, cmd, data);
+		break;
+
 	case SIOCSIFMETRIC:
 		error = suser_td(td);
 		if (error)
diff --git a/sys/net/if.h b/sys/net/if.h
index 70428bfca28a..b0cc9053a934 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -136,6 +136,10 @@ struct if_data {
 	(IFF_BROADCAST|IFF_POINTOPOINT|IFF_RUNNING|IFF_OACTIVE|\
 	    IFF_SIMPLEX|IFF_MULTICAST|IFF_ALLMULTI|IFF_SMART)
 
+/* Capabilities that interfaces can advertise. */
+#define IFCAP_HWCSUM		0x0001  /* can do hardware checksums */
+#define IFCAP_NETCONS		0x0002  /* can be a network console */
+
 #define	IFQ_MAXLEN	50
 #define	IFNET_SLOWHZ	1		/* granularity is 1 second */
 
@@ -198,6 +202,7 @@ struct	ifreq {
 		int	ifru_phys;
 		int	ifru_media;
 		caddr_t	ifru_data;
+		int	ifru_cap[2];
 	} ifr_ifru;
 #define	ifr_addr	ifr_ifru.ifru_addr	/* address */
 #define	ifr_dstaddr	ifr_ifru.ifru_dstaddr	/* other end of p-to-p link */
@@ -209,6 +214,8 @@ struct	ifreq {
 #define ifr_phys	ifr_ifru.ifru_phys	/* physical wire */
 #define ifr_media	ifr_ifru.ifru_media	/* physical media */
 #define	ifr_data	ifr_ifru.ifru_data	/* for use by interface */
+#define	ifr_reqcap	ifr_ifru.ifru_cap[0]	/* requested capabilities */
+#define	ifr_curcap	ifr_ifru.ifru_cap[1]	/* current capabilities */
 };
 
 #define	_SIZEOF_ADDR_IFREQ(ifr) \
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 597eb644f8de..0d6979126c05 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -117,6 +117,8 @@ struct ifnet {
 	short	if_unit;		/* sub-unit for lower level driver */
 	short	if_timer;		/* time 'til if_watchdog called */
 	short	if_flags;		/* up/down, broadcast, etc. */
+	int	if_capabilities;	/* interface capabilities */
+	int	if_capenable;		/* enabled features */
 	int	if_mpsafe;		/* XXX TEMPORARY */
 	int	if_ipending;		/* interrupts pending */
 	void	*if_linkmib;		/* link-type-specific MIB data */