[src/trunk]: src/sys/net Add code to auto-deencapsulate 0 tagged VLANs.

[matt <matt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fcd119cefd52
branches:  trunk
changeset: 765371:fcd119cefd52
user:      matt <matt%NetBSD.org@localhost>
date:      Tue May 24 17:16:43 2011 +0000

description:
Add code to auto-deencapsulate 0 tagged VLANs.

diffstat:

 sys/net/if_ethersubr.c |  31 ++++++++++++++++++++++++-------
 1 files changed, 24 insertions(+), 7 deletions(-)

diffs (98 lines):

diff -r 171519c8253e -r fcd119cefd52 sys/net/if_ethersubr.c
--- a/sys/net/if_ethersubr.c    Tue May 24 16:42:53 2011 +0000
+++ b/sys/net/if_ethersubr.c    Tue May 24 17:16:43 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_ethersubr.c,v 1.186 2011/04/25 22:14:45 yamt Exp $  */
+/*     $NetBSD: if_ethersubr.c,v 1.187 2011/05/24 17:16:43 matt Exp $  */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -61,7 +61,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.186 2011/04/25 22:14:45 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.187 2011/05/24 17:16:43 matt Exp $");
 
 #include "opt_inet.h"
 #include "opt_atalk.h"
@@ -115,9 +115,7 @@
 #include <net/bpf.h>
 
 #include <net/if_ether.h>
-#if NVLAN > 0
 #include <net/if_vlanvar.h>
-#endif
 
 #if NPPPOE > 0
 #include <net/if_pppoe.h>
@@ -637,6 +635,7 @@
        struct ifqueue *inq;
        uint16_t etype;
        struct ether_header *eh;
+       size_t ehlen;
 #if defined (ISO) || defined (LLC) || defined(NETATALK)
        struct llc *l;
 #endif
@@ -651,6 +650,7 @@
 #endif
        eh = mtod(m, struct ether_header *);
        etype = ntohs(eh->ether_type);
+       ehlen = sizeof(*eh);
 
        /*
         * Determine if the packet is within its size limits.
@@ -748,6 +748,7 @@
 
                eh = mtod(m, struct ether_header *);
                etype = ntohs(eh->ether_type);
+               ehlen = sizeof(*eh);
        }
 #endif
 
@@ -783,8 +784,23 @@
         * (and possibly FCS) intact.
         */
        switch (etype) {
+       case ETHERTYPE_VLAN: {
+               struct ether_vlan_header *evl = (void *)eh;
+               /*
+                * If there is a tag of 0, then the VLAN header was probably
+                * just being used to store the priority.  Extract the ether
+                * type, and if IP or IPV6, let them deal with it. 
+                */
+               if (m->m_len <= sizeof(*evl)
+                   && EVL_VLANOFTAG(evl->evl_tag) == 0) {
+                       etype = ntohs(evl->evl_proto);
+                       ehlen = sizeof(*evl);
+                       if ((m->m_flags & M_PROMISC) == 0
+                           && (etype == ETHERTYPE_IP
+                               || etype == ETHERTYPE_IPV6))
+                               break;
+               }
 #if NVLAN > 0
-       case ETHERTYPE_VLAN:
                /*
                 * vlan_input() will either recursively call ether_input()
                 * or drop the packet.
@@ -792,9 +808,10 @@
                if (((struct ethercom *)ifp)->ec_nvlans != 0)
                        vlan_input(ifp, m);
                else
+#endif /* NVLAN > 0 */
                        m_freem(m);
                return;
-#endif /* NVLAN > 0 */
+       }
 #if NPPPOE > 0
        case ETHERTYPE_PPPOEDISC:
        case ETHERTYPE_PPPOE:
@@ -872,7 +889,7 @@
 
        if (etype > ETHERMTU + sizeof (struct ether_header)) {
                /* Strip off the Ethernet header. */
-               m_adj(m, sizeof(struct ether_header));
+               m_adj(m, ehlen);
 
                switch (etype) {
 #ifdef INET