FreeBSD/Linux Kernel Cross Reference
sys/modules/netgraph/tee/ng_tee.4

     .\" Copyright (c) 1996-1999 Whistle Communications, Inc.
     .\" All rights reserved.
     .\" 
     .\" Subject to the following obligations and disclaimer of warranty, use and
     .\" redistribution of this software, in source or object code forms, with or
     .\" without modifications are expressly permitted by Whistle Communications;
     .\" provided, however, that:
     .\" 1. Any and all reproductions of the source or object code must include the
     .\"    copyright notice above and the following disclaimer of warranties; and
    .\" 2. No rights are granted, in any manner or form, to use Whistle
    .\"    Communications, Inc. trademarks, including the mark "WHISTLE
    .\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
    .\"    such appears in the above copyright notice or in the software.
    .\" 
    .\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
    .\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
    .\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
    .\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
    .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
    .\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
    .\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
    .\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
    .\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
    .\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
    .\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
    .\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
    .\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
    .\" OF SUCH DAMAGE.
    .\" 
    .\" Author: Archie Cobbs <archie@freebsd.org>
    .\"
    .\" $FreeBSD$
    .\" $Whistle: ng_tee.8,v 1.4 1999/01/25 23:46:27 archie Exp $
    .\"
    .Dd January 19, 1999
    .Dt NG_TEE 4
    .Os FreeBSD
    .Sh NAME
    .Nm ng_tee
    .Nd netgraph ``tee'' node type
    .Sh SYNOPSIS
    .Fd #include <netgraph/ng_tee.h>
    .Sh DESCRIPTION
    The
    .Nm tee
    node type has a purpose similar to the
    .Xr tee 1
    command.
    .Nm Tee
    nodes are useful for debugging or
    .Dq snooping
    on a connection
    between two netgraph nodes.
    .Nm Tee
    nodes have four hooks,
    .Dv right ,
    .Dv left ,
    .Dv right2left ,
    and
    .Dv left2right .
    All data received on
    .Dv right
    is sent unmodified to
    .Em both
    hooks
    .Dv left
    and
    .Dv right2left .
    Similarly, all data received on
    .Dv left
    is sent unmodified to both
    .Dv right
    and
    .Dv left2right .
    .Pp
    Packets may also be received on
    .Dv right2left
    and
    .Dv left2right ;
    if so, they are forwarded unchanged out hooks
    .Dv left
    and
    .Dv right ,
    respectively.
    .Sh HOOKS
    This node type supports the following hooks:
    .Pp
    .Bl -tag -width foobarbarfoo
    .It Dv right
    The connection to the node on the right.
    .It Dv left
    The connection to the node on the left.
    .It Dv right2left
    Tap for right to left traffic.
    .It Dv left2right
    Tap for left to right traffic.
   .El
   .Sh CONTROL MESSAGES
   This node type supports the generic control messages, plus the following.
   .Bl -tag -width foo
   .It Dv NGM_TEE_GET_STATS
   Get statistics, returned as a
   .Dv "struct ng_tee_stats" .
   .It Dv NGM_TEE_CLR_STATS
   Clear statistics.
   .El
   .Sh SHUTDOWN
   This node shuts down upon receipt of a
   .Dv NGM_SHUTDOWN
   control message, or when all hooks have been disconnected.
   .Sh SEE ALSO
   .Xr tee 1 ,
   .Xr netgraph 4 ,
   .Xr ngctl 8
   .Sh HISTORY
   The
   .Nm
   node type was implemented in
   .Fx 4.0 .
   .Sh AUTHORS
   .An Julian Elischer Aq julian@freebsd.org

Cache object: 49c2cfc143d7e9d0badec7189502aa0b