Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
branch: master
Fetching contributors…

Cannot retrieve contributors at this time

565 lines (506 sloc) 16.925 kb
/*
* 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.
*
* $FreeBSD: src/sys/net/if_vlan.c,v 1.4.2.3 1999/12/25 03:28:51 jkh Exp $
*/
/*
* 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.
*
*
* XXX It's incorrect to assume that we must always kludge up
* headers on the physical device's behalf: some devices support
* VLAN tag insersion and extraction in firmware. For these cases,
* one can change the behavior of the vlan interface by setting
* the LINK0 flag on it (that is setting the vlan interface's LINK0
* flag, _not_ the parent's LINK0 flag; we try to leave the parent
* alone). If the interface as the LINK0 flag set, then it will
* not modify the ethernet header on output because the parent
* can do that for itself. On input, the parent can call vlan_input_tag()
* directly in order to supply us with an incoming mbuf and the vlan
* tag value that goes with it.
*/
#include "vlan.h"
#if NVLAN > 0
#include "opt_inet.h"
#include "opt_inet6.h"
#include "bpfilter.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/queue.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, u_long cmd, caddr_t addr);
static int vlan_setmulti(struct ifnet *ifp);
static int vlan_unconfig(struct ifnet *ifp);
static int vlan_config(struct ifvlan *ifv, struct ifnet *p);
/*
* Program our multicast filter. What we're actually doing is
* programming the multicast filter of the parent. This has the
* side effect of causing the parent interface to receive multicast
* traffic that it doesn't really want, which ends up being discarded
* later by the upper protocol layers. Unfortunately, there's no way
* to avoid this: there really is only one physical interface.
*/
static int vlan_setmulti(struct ifnet *ifp)
{
struct ifnet *ifp_p;
struct ifmultiaddr *ifma, *rifma = NULL;
struct ifvlan *sc;
struct vlan_mc_entry *mc = NULL;
struct sockaddr_dl sdl;
int error;
/* Find the parent. */
sc = ifp->if_softc;
ifp_p = sc->ifv_p;
sdl.sdl_len = ETHER_ADDR_LEN;
sdl.sdl_family = AF_LINK;
/* First, remove any existing filter entries. */
while(sc->vlan_mc_listhead.slh_first != NULL) {
mc = sc->vlan_mc_listhead.slh_first;
bcopy((char *)&mc->mc_addr, LLADDR(&sdl), ETHER_ADDR_LEN);
error = if_delmulti(ifp_p, (struct sockaddr *)&sdl);
if (error)
return(error);
SLIST_REMOVE_HEAD(&sc->vlan_mc_listhead, mc_entries);
free(mc, M_DEVBUF);
}
/* Now program new ones. */
for (ifma = ifp->if_multiaddrs.lh_first;
ifma != NULL;ifma = ifma->ifma_link.le_next) {
if (ifma->ifma_addr->sa_family != AF_LINK)
continue;
mc = malloc(sizeof(struct vlan_mc_entry), M_DEVBUF, M_NOWAIT);
bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
(char *)&mc->mc_addr, ETHER_ADDR_LEN);
SLIST_INSERT_HEAD(&sc->vlan_mc_listhead, mc, mc_entries);
error = if_addmulti(ifp_p, (struct sockaddr *)&sdl, &rifma);
if (error)
return(error);
}
return(0);
}
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;
ifp->if_snd.ifq_maxlen = ifqmaxlen;
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)
{
return;
}
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(ifp, m);
#endif /* NBPFILTER > 0 */
/*
* If the LINK0 flag is set, it means the underlying interface
* can do VLAN tag insertion itself and doesn't require us to
* create a special header for it. In this case, we just pass
* the packet along. However, we need some way to tell the
* interface where the packet came from so that it knows how
* to find the VLAN tag to use, so we set the rcvif in the
* mbuf header to our ifnet.
*
* Note: we also set the M_PROTO1 flag in the mbuf to let
* the parent driver know that the rcvif pointer is really
* valid. We need to do this because sometimes mbufs will
* be allocated by other parts of the system that contain
* garbage in the rcvif pointer. Using the M_PROTO1 flag
* lets the driver perform a proper sanity check and avoid
* following potentially bogus rcvif pointers off into
* never-never land.
*/
if (ifp->if_flags & IFF_LINK0) {
m->m_pkthdr.rcvif = ifp;
m->m_flags |= M_PROTO1;
} else {
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);
#ifdef DEBUG
printf("vlan_start: %*D\n", sizeof *evl,
(char *)evl, ":");
#endif
}
/*
* 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 */
ifp->if_oerrors++;
m_freem(m);
continue;
}
IF_ENQUEUE(&p->if_snd, m);
if ((p->if_flags & IFF_OACTIVE) == 0) {
p->if_start(p);
ifp->if_opackets++;
}
}
ifp->if_flags &= ~IFF_OACTIVE;
}
int
vlan_input_tag(struct ether_header *eh, struct mbuf *m, u_int16_t t)
{
int i;
struct ifvlan *ifv;
for (i = 0; i < NVLAN; i++) {
ifv = &ifv_softc[i];
if (ifv->ifv_tag == t)
break;
}
if (i >= NVLAN || (ifv->ifv_if.if_flags & IFF_UP) == 0) {
m_free(m);
return -1; /* So the parent can take note */
}
/*
* Having found a valid vlan interface corresponding to
* the given source interface and vlan tag, run the
* the real packet through ethert_input().
*/
m->m_pkthdr.rcvif = &ifv->ifv_if;
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);
}
ifv->ifv_if.if_ipackets++;
ether_input(&ifv->ifv_if, eh, m);
return 0;
}
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;
/*
* Preserve the state of the LINK0 flag for ourselves.
*/
ifv->ifv_if.if_flags = (p->if_flags & ~(IFF_LINK0));
/*
* Set up our ``Ethernet address'' to reflect the underlying
* physical interface's.
*/
ifa1 = ifnet_addrs[ifv->ifv_if.if_index];
ifa2 = ifnet_addrs[p->if_index];
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_unconfig(struct ifnet *ifp)
{
struct ifaddr *ifa;
struct sockaddr_dl *sdl;
struct vlan_mc_entry *mc;
struct ifvlan *ifv;
struct ifnet *p;
int error;
ifv = ifp->if_softc;
p = ifv->ifv_p;
/*
* Since the interface is being unconfigured, we need to
* empty the list of multicast groups that we may have joined
* while we were alive and remove them from the parent's list
* as well.
*/
while(ifv->vlan_mc_listhead.slh_first != NULL) {
struct sockaddr_dl sdl;
sdl.sdl_len = ETHER_ADDR_LEN;
sdl.sdl_family = AF_LINK;
mc = ifv->vlan_mc_listhead.slh_first;
bcopy((char *)&mc->mc_addr, LLADDR(&sdl), ETHER_ADDR_LEN);
error = if_delmulti(p, (struct sockaddr *)&sdl);
error = if_delmulti(ifp, (struct sockaddr *)&sdl);
if (error)
return(error);
SLIST_REMOVE_HEAD(&ifv->vlan_mc_listhead, mc_entries);
free(mc, M_DEVBUF);
}
/* Disconnect from parent. */
ifv->ifv_p = NULL;
ifv->ifv_if.if_mtu = ETHERMTU;
/* Clear our MAC address. */
ifa = ifnet_addrs[ifv->ifv_if.if_index];
sdl = (struct sockaddr_dl *)ifa->ifa_addr;
sdl->sdl_type = IFT_ETHER;
sdl->sdl_alen = ETHER_ADDR_LEN;
bzero(LLADDR(sdl), ETHER_ADDR_LEN);
bzero(ifv->ifv_ac.ac_enaddr, ETHER_ADDR_LEN);
return 0;
}
static int
vlan_ioctl(struct ifnet *ifp, u_long 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.
* This is bogus. The underlying interface might support
* jumbo frames.
*/
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') {
vlan_unconfig(ifp);
ifv->ifv_p = 0;
if_down(ifp);
ifp->if_flags &= ~(IFF_UP|IFF_RUNNING);
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;
ifp->if_flags |= IFF_RUNNING;
break;
case SIOCGETVLAN:
bzero(&vlr, sizeof vlr);
if (ifv->ifv_p) {
snprintf(vlr.vlr_parent, sizeof(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;
case SIOCADDMULTI:
case SIOCDELMULTI:
error = vlan_setmulti(ifp);
break;
default:
error = EINVAL;
}
return error;
}
#endif /* NVLAN > 0 */
Jump to Line
Something went wrong with that request. Please try again.