Add support for 802.1ad-style QinQ nested VLANs.

QinQ-compliant svlan (service VLAN) interfaces are implemented as
a new cloner type, use Ethernet type 0x88a8, and have a dedicated
VLAN tag hash to avoid ID conflicts.  vlan(4) interfaces can be
stacked on top of svlan(4).

Originally from reyk@, input from claudio@ and deraadt@
ok claudio@

1 files changed, 35 insertions, 5 deletions

diff --git a/share/man/man4/vlan.4 b/share/man/man4/vlan.4
index 77034b7f731..8ac6b882a1e 100644
--- a/share/man/man4/vlan.4
+++ b/share/man/man4/vlan.4
@@ -1,4 +1,4 @@
-.\" $OpenBSD: vlan.4,v 1.31 2008/06/26 05:42:07 ray Exp $
+.\" $OpenBSD: vlan.4,v 1.32 2010/06/03 16:15:00 naddy Exp $
 .\"
 .\" Copyright (c) 2000 The NetBSD Foundation, Inc.
 .\" All rights reserved.
@@ -27,12 +27,13 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: June 26 2008 $
+.Dd $Mdocdate: June 3 2010 $
 .Dt VLAN 4
 .Os
 .Sh NAME
-.Nm vlan
-.Nd "IEEE 802.1Q encapsulation/decapsulation pseudo-device"
+.Nm vlan ,
+.Nm svlan
+.Nd "IEEE 802.1Q/1AD encapsulation/decapsulation pseudo-devices"
 .Sh SYNOPSIS
 .Cd "pseudo-device vlan"
 .Sh DESCRIPTION
@@ -40,6 +41,10 @@ The
 .Nm
 Ethernet interface allows construction of virtual LANs when used in
 conjunction with IEEE 802.1Q-compliant Ethernet devices.
+The
+.Ic svlan
+Ethernet interface allows contruction of IEEE 802.1AD-compliant
+provider bridges.
 .Pp
 A
 .Nm
@@ -83,6 +88,24 @@ option for more information.
 Following the vlan header is the actual ether type for the frame and length
 information.
 .Pp
+An
+.Ic svlan
+interface is normally used for QinQ in 802.1AD-compliant provider bridges to
+stack other
+.Nm
+interfaces on top of it.
+It can be created using the
+.Ic ifconfig svlan Ns Ar N Ic create
+command or by setting up a
+.Xr hostname.if 5
+configuration file for
+.Xr netstart 8 .
+The configuration is identical to the
+.Nm
+interface, the only differences are that it uses a different Ethernet
+type (0x88a8) and an independent VLAN ID space on the parent
+interface.
+.Pp
 .Nm
 interfaces support the following unique
 .Xr ioctl 2 Ns s :
@@ -104,7 +127,10 @@ interfaces use the following interface capabilities:
 The parent interface can handle full sized frames, plus the size
 of the vlan tag.
 .It IFCAP_VLAN_HWTAGGING
-The parent interface will participate in the tagging of frames.
+The parent interface will participate in the tagging of frames
+(This is not supported by
+.Ic svlan
+interfaces).
 .El
 .Sh DIAGNOSTICS
 .Bl -diag
@@ -151,6 +177,10 @@ and
 .%T IEEE 802.1Q standard
 .%O http://standards.ieee.org/getieee802/802.1.html
 .Re
+.Rs
+.%T IEEE 802.1AD standard
+.%O Provider Bridges, QinQ
+.Re
 .Sh AUTHORS
 Originally wollman@freebsd.org.
 .Sh BUGS