/*
* ng_ether_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>
* $Whistle: ng_echo.c,v 1.13 1999/11/01 09:24:51 julian Exp $
*/
/*
* Netgraph "ether_echo" node
*
* This node simply bounces data and messages back to whence they came.
* However it swaps the source and destination ether fields.
* No testing is done!
*/
#include <sys/param.h>
#include <sys/systm.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_ether_echo.h>
#include <net/ethernet.h>
/* Netgraph methods */
static ng_constructor_t ngee_cons;
static ng_rcvmsg_t ngee_rcvmsg;
static ng_rcvdata_t ngee_rcvdata;
static ng_disconnect_t ngee_disconnect;
/* Netgraph type */
static struct ng_type typestruct = {
.version = NG_ABI_VERSION,
.name = NG_ETHER_ECHO_NODE_TYPE,
.constructor = ngee_cons,
.rcvmsg = ngee_rcvmsg,
.rcvdata = ngee_rcvdata,
.disconnect = ngee_disconnect,
};
NETGRAPH_INIT(ether_echo, &typestruct);
static int
ngee_cons(node_p node)
{
return (0);
}
/*
* Receive control message. We just bounce it back as a reply.
*/
static int
ngee_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
struct ng_mesg *msg;
int error = 0;
NGI_GET_MSG(item, msg);
msg->header.flags |= NGF_RESP;
NG_RESPOND_MSG(error, node, item, msg);
return (error);
}
/*
* Receive data
*/
static int
ngee_rcvdata(hook_p hook, item_p item)
{
int error;
struct mbuf *m;
struct ether_header *eh;
struct ether_addr tmpaddr;
/* Make sure we have an entire header */
NGI_GET_M(item, m);
if (m->m_len < sizeof(*eh) ) {
m = m_pullup(m, sizeof(*eh));
if (m == NULL) {
NG_FREE_ITEM(item);
return(EINVAL);
}
}
eh = mtod(m, struct ether_header *);
/* swap the source and destination fields */
bcopy(eh->ether_dhost, &tmpaddr, ETHER_ADDR_LEN);
bcopy(eh->ether_shost, eh->ether_dhost, ETHER_ADDR_LEN);
bcopy(&tmpaddr, eh->ether_shost, ETHER_ADDR_LEN);
NG_FWD_NEW_DATA(error, item, hook, m);
return (error);
}
/*
* Removal of the last link destroys the nodeo
*/
static int
ngee_disconnect(hook_p hook)
{
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
ng_rmnode_self(NG_HOOK_NODE(hook));
}
return (0);
}
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