freebsd-skq/sys/netgraph/ng_echo.c
Julian Elischer 589f6ed8ce Divorce the kernel binary ABI version number from the message
format version number. (userland programs should not need to be
recompiled when the netgraph kernel internal ABI is changed.

Also fix modules that don;t handle the fact that a caller may not supply
a return message pointer. (benign at the moment because the calling code
checks, but that will change)
2000-12-18 20:03:32 +00:00

119 lines
3.4 KiB
C

/*
* ng_echo.c
*
* 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: Julian Elisher <julian@freebsd.org>
*
* $FreeBSD$
* $Whistle: ng_echo.c,v 1.13 1999/11/01 09:24:51 julian Exp $
*/
/*
* Netgraph "echo" node
*
* This node simply bounces data and messages back to whence they came.
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_echo.h>
/* Netgraph methods */
static ng_rcvmsg_t nge_rcvmsg;
static ng_rcvdata_t nge_rcvdata;
static ng_disconnect_t nge_disconnect;
/* Netgraph type */
static struct ng_type typestruct = {
NG_ABI_VERSION,
NG_ECHO_NODE_TYPE,
NULL,
NULL,
nge_rcvmsg,
NULL,
NULL,
NULL,
NULL,
nge_rcvdata,
nge_disconnect,
NULL
};
NETGRAPH_INIT(echo, &typestruct);
/*
* Receive control message. We just bounce it back as a reply.
*/
static int
nge_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
struct ng_mesg **rptr, hook_p lasthook)
{
if (rptr) {
msg->header.flags |= NGF_RESP;
*rptr = msg;
} else {
FREE(msg, M_NETGRAPH);
}
return (0);
}
/*
* Receive data
*/
static int
nge_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
{
int error = 0;
NG_SEND_DATA(error, hook, m, meta);
return (error);
}
/*
* Removal of the last link destroys the nodeo
*/
static int
nge_disconnect(hook_p hook)
{
if (hook->node->numhooks == 0)
ng_rmnode(hook->node);
return (0);
}