Add preliminary support for IEEE 802.1Q VLAN tagging. It doesn't actually

work reliably yet (I've had panics), but it does seem to occasionally
be able to transmit and receive syntactically-correct packets.
Also fixes one of if_ethersubr.c's legion style bugs, and removes
the hostcache code from standard kernels---the code that depends on it
is not going to happen any time soon, I'm afraid.

1 files changed, 363 insertions, 0 deletions

diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c
new file mode 100644
index 0000000..eb28226
--- /dev/null
+++ b/sys/net/if_vlan.c
@@ -0,0 +1,363 @@
+/*
+ * Copyright 1998 Massachusetts Institute of Technology
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose and without fee is hereby
+ * granted, provided that both the above copyright notice and this
+ * permission notice appear in all copies, that both the above
+ * copyright notice and this permission notice appear in all
+ * supporting documentation, and that the name of M.I.T. not be used
+ * in advertising or publicity pertaining to distribution of the
+ * software without specific, written prior permission.  M.I.T. makes
+ * no representations about the suitability of this software for any
+ * purpose.  It is provided "as is" without express or implied
+ * warranty.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
+ * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
+ * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$Id$
+ */
+
+/*
+ * if_vlan.c - pseudo-device driver for IEEE 802.1Q virtual LANs.
+ * Might be extended some day to also handle IEEE 802.1p priority
+ * tagging.  This is sort of sneaky in the implementation, since
+ * we need to pretend to be enough of an Ethernet implementation
+ * to make arp work.  The way we do this is by telling everyone
+ * that we are an Ethernet, and then catch the packets that
+ * ether_output() left on our output queue queue when it calls
+ * if_start(), rewrite them for use by the real outgoing interface,
+ * and ask it to send them.
+ */
+
+#include "vlan.h"
+#if NVLAN > 0
+#include "opt_inet.h"
+#include "bpfilter.h"
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
+#include <sys/sysctl.h>
+#include <sys/systm.h>
+
+#if NBPFILTER > 0
+#include <net/bpf.h>
+#endif
+#include <net/ethernet.h>
+#include <net/if.h>
+#include <net/if_arp.h>
+#include <net/if_dl.h>
+#include <net/if_types.h>
+#include <net/if_vlan_var.h>
+
+#ifdef INET
+#include <netinet/in.h>
+#include <netinet/if_ether.h>
+#endif
+
+SYSCTL_NODE(_net_link, IFT_8021_VLAN, vlan, CTLFLAG_RW, 0, "IEEE 802.1Q VLAN");
+SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0, "for consistency");
+
+u_int	vlan_proto = ETHERTYPE_VLAN;
+SYSCTL_INT(_net_link_vlan_link, VLANCTL_PROTO, proto, CTLFLAG_RW, &vlan_proto,
+	   0, "Ethernet protocol used for VLAN encapsulation");
+
+static	struct ifvlan ifv_softc[NVLAN];
+
+static	void vlan_start(struct ifnet *ifp);
+static	void vlan_ifinit(void *foo);
+static	int vlan_ioctl(struct ifnet *ifp, int cmd, caddr_t addr);
+
+static void
+vlaninit(void *dummy)
+{
+	int i;
+
+	for (i = 0; i < NVLAN; i++) {
+		struct ifnet *ifp = &ifv_softc[i].ifv_if;
+
+		ifp->if_softc = &ifv_softc[i];
+		ifp->if_name = "vlan";
+		ifp->if_unit = i;
+		/* NB: flags are not set here */
+		ifp->if_linkmib = &ifv_softc[i].ifv_mib;
+		ifp->if_linkmiblen = sizeof ifv_softc[i].ifv_mib;
+		/* NB: mtu is not set here */
+
+		ifp->if_init = vlan_ifinit;
+		ifp->if_start = vlan_start;
+		ifp->if_ioctl = vlan_ioctl;
+		ifp->if_output = ether_output;
+		if_attach(ifp);
+		ether_ifattach(ifp);
+#if NBPFILTER > 0
+		bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
+#endif
+		/* Now undo some of the damage... */
+		ifp->if_data.ifi_type = IFT_8021_VLAN;
+		ifp->if_data.ifi_hdrlen = EVL_ENCAPLEN;
+		ifp->if_resolvemulti = 0;
+	}
+}
+PSEUDO_SET(vlaninit, if_vlan);
+
+static void
+vlan_ifinit(void *foo)
+{
+	;
+}
+
+static void
+vlan_start(struct ifnet *ifp)
+{
+	struct ifvlan *ifv;
+	struct ifnet *p;
+	struct ether_vlan_header *evl;
+	struct mbuf *m;
+
+	ifv = ifp->if_softc;
+	p = ifv->ifv_p;
+
+	ifp->if_flags |= IFF_OACTIVE;
+	for (;;) {
+		IF_DEQUEUE(&ifp->if_snd, m);
+		if (m == 0)
+			break;
+#if NBPFILTER > 0
+		if (ifp->if_bpf)
+			bpf_mtap(m, ifp);
+#endif /* NBPFILTER > 0 */
+
+		M_PREPEND(m, EVL_ENCAPLEN, M_DONTWAIT);
+		if (m == 0)
+			continue;
+		/* M_PREPEND takes care of m_len, m_pkthdr.len for us */
+
+		/*
+		 * Transform the Ethernet header into an Ethernet header
+		 * with 802.1Q encapsulation.
+		 */
+		bcopy(mtod(m, char *) + EVL_ENCAPLEN, mtod(m, char *),
+		      sizeof(struct ether_header));
+		evl = mtod(m, struct ether_vlan_header *);
+		evl->evl_proto = evl->evl_encap_proto;
+		evl->evl_encap_proto = htons(vlan_proto);
+		evl->evl_tag = htons(ifv->ifv_tag);
+		printf("vlan_start: %*D\n", sizeof *evl, (char *)evl, ":");
+
+		/*
+		 * Send it, precisely as ether_output() would have.
+		 * We are already running at splimp.
+		 */
+		if (IF_QFULL(&p->if_snd)) {
+			IF_DROP(&p->if_snd);
+				/* XXX stats */
+		}
+		IF_ENQUEUE(&p->if_snd, m);
+		if ((p->if_flags & IFF_OACTIVE) == 0)
+			p->if_start(p);
+	}
+	ifp->if_flags &= ~IFF_OACTIVE;
+}
+
+int
+vlan_input(struct ether_header *eh, struct mbuf *m)
+{
+	int i;
+	struct ifvlan *ifv;
+
+	for (i = 0; i < NVLAN; i++) {
+		ifv = &ifv_softc[i];
+		if (m->m_pkthdr.rcvif == ifv->ifv_p
+		    && (EVL_VLANOFTAG(ntohs(*mtod(m, u_int16_t *)))
+			== ifv->ifv_tag))
+			break;
+	}
+
+	if (i >= NVLAN || (ifv->ifv_if.if_flags & IFF_UP) == 0) {
+		m_freem(m);
+		return -1;	/* so ether_input can take note */
+	}
+
+	/*
+	 * Having found a valid vlan interface corresponding to
+	 * the given source interface and vlan tag, remove the
+	 * encapsulation, and run the real packet through
+	 * ether_input() a second time (it had better be
+	 * reentrant!).
+	 */
+	m->m_pkthdr.rcvif = &ifv->ifv_if;
+	eh->ether_type = mtod(m, u_int16_t *)[1];
+	m->m_data += EVL_ENCAPLEN;
+	m->m_len -= EVL_ENCAPLEN;
+	m->m_pkthdr.len -= EVL_ENCAPLEN;
+
+#if NBPFILTER > 0
+	if (ifv->ifv_if.if_bpf) {
+		/*
+		 * Do the usual BPF fakery.  Note that we don't support
+		 * promiscuous mode here, since it would require the
+		 * drivers to know about VLANs and we're not ready for
+		 * that yet.
+		 */
+		struct mbuf m0;
+		m0.m_next = m;
+		m0.m_len = sizeof(struct ether_header);
+		m0.m_data = (char *)eh;
+		bpf_mtap(&ifv->ifv_if, &m0);
+	}
+#endif
+	ether_input(&ifv->ifv_if, eh, m);
+	return 0;
+}
+
+static int
+vlan_config(struct ifvlan *ifv, struct ifnet *p)
+{
+	struct ifaddr *ifa1, *ifa2;
+	struct sockaddr_dl *sdl1, *sdl2;
+
+	if (p->if_data.ifi_type != IFT_ETHER)
+		return EPROTONOSUPPORT;
+	if (ifv->ifv_p)
+		return EBUSY;
+	ifv->ifv_p = p;
+	if (p->if_data.ifi_hdrlen == sizeof(struct ether_vlan_header))
+		ifv->ifv_if.if_mtu = p->if_mtu;
+	else
+		ifv->ifv_if.if_mtu = p->if_data.ifi_mtu - EVL_ENCAPLEN;
+
+	/*
+	 * NB: we don't support multicast at this point.
+	 */
+	ifv->ifv_if.if_flags = (p->if_flags & ~IFF_MULTICAST); /* XXX */
+
+	/*
+	 * Set up our ``Ethernet address'' to reflect the underlying
+	 * physical interface's.
+	 */
+	ifa1 = ifnet_addrs[ifv->ifv_if.if_index - 1];
+	ifa2 = ifnet_addrs[p->if_index - 1];
+	sdl1 = (struct sockaddr_dl *)ifa1->ifa_addr;
+	sdl2 = (struct sockaddr_dl *)ifa2->ifa_addr;
+	sdl1->sdl_type = IFT_ETHER;
+	sdl1->sdl_alen = ETHER_ADDR_LEN;
+	bcopy(LLADDR(sdl2), LLADDR(sdl1), ETHER_ADDR_LEN);
+	bcopy(LLADDR(sdl2), ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN);
+	return 0;
+}
+
+static int
+vlan_ioctl(struct ifnet *ifp, int cmd, caddr_t data)
+{
+	struct ifaddr *ifa;
+	struct ifnet *p;
+	struct ifreq *ifr;
+	struct ifvlan *ifv;
+	struct vlanreq vlr;
+	int error = 0;
+
+	ifr = (struct ifreq *)data;
+	ifa = (struct ifaddr *)data;
+	ifv = ifp->if_softc;
+
+	switch (cmd) {
+	case SIOCSIFADDR:
+		ifp->if_flags |= IFF_UP;
+
+		switch (ifa->ifa_addr->sa_family) {
+#ifdef INET
+		case AF_INET:
+			arp_ifinit(&ifv->ifv_ac, ifa);
+			break;
+#endif
+		default:
+			break;
+		}
+		break;
+
+	case SIOCGIFADDR:
+		{
+			struct sockaddr *sa;
+
+			sa = (struct sockaddr *) &ifr->ifr_data;
+			bcopy(((struct arpcom *)ifp->if_softc)->ac_enaddr,
+			      (caddr_t) sa->sa_data, ETHER_ADDR_LEN);
+		}
+		break;
+
+	case SIOCSIFMTU:
+		/*
+		 * Set the interface MTU.
+		 */
+		if (ifr->ifr_mtu > ETHERMTU) {
+			error = EINVAL;
+		} else {
+			ifp->if_mtu = ifr->ifr_mtu;
+		}
+		break;
+
+	case SIOCSETVLAN:
+		error = copyin(ifr->ifr_data, &vlr, sizeof vlr);
+		if (error)
+			break;
+		if (vlr.vlr_parent[0] == '\0') {
+			ifv->ifv_p = 0;
+			if_down(ifp);
+			break;
+		}
+		p = ifunit(vlr.vlr_parent);
+		if (p == 0) {
+			error = ENOENT;
+			break;
+		}
+		error = vlan_config(ifv, p);
+		if (error)
+			break;
+		ifv->ifv_tag = vlr.vlr_tag;
+		break;
+		
+	case SIOCGETVLAN:
+		bzero(&vlr, sizeof vlr);
+		if (ifv->ifv_p) {
+			sprintf(vlr.vlr_parent, "%s%d", ifv->ifv_p->if_name,
+				ifv->ifv_p->if_unit);
+			vlr.vlr_tag = ifv->ifv_tag;
+		}
+		error = copyout(&vlr, ifr->ifr_data, sizeof vlr);
+		break;
+		
+	case SIOCSIFFLAGS:
+		/*
+		 * We don't support all-multicast or promiscuous modes
+		 * right now because it would require help from the
+		 * underlying drivers, which hasn't been implemented.
+		 */
+		if (ifr->ifr_flags & (IFF_PROMISC|IFF_ALLMULTI)) {
+			ifp->if_flags &= ~(IFF_PROMISC|IFF_ALLMULTI);
+			error = EINVAL;
+		}
+		break;
+
+		/* NB: this will reject multicast state changes */
+	default:
+		error = EINVAL;
+	}
+	return error;
+}
+
+#endif /* NVLAN > 0 */