HardenedBSD/sys/netgraph/ng_ip_input.c

/*
 * ng_ip_input.c
 */

/*-
 * SPDX-License-Identifier: BSD-3-Clause AND BSD-2-Clause
 *
 * Copyright 2001 The Aerospace Corporation.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions, and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions, and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  The name of The Aerospace Corporation may not be used to endorse or
 *     promote products derived from this software.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * 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:		Brooks Davis <brooks@FreeBSD.org>
 * Derived from:	ng_hole.c
 */

/*
 * This node simply takes IP packets and calls ip_input on them
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/proc.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <net/netisr.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_ip_input.h>

/* Netgraph methods */
static ng_constructor_t	ngipi_cons;
static ng_rcvdata_t	ngipi_rcvdata;
static ng_disconnect_t	ngipi_disconnect;

static struct ng_type typestruct = {
	.version =	NG_ABI_VERSION,
	.name =		NG_IP_INPUT_NODE_TYPE,
	.constructor =	ngipi_cons,
	.rcvdata =	ngipi_rcvdata,
	.disconnect =	ngipi_disconnect,
};
NETGRAPH_INIT(ip_input, &typestruct);

/* 
 * Be obliging. but no work to do.
 */
static int
ngipi_cons(node_p node)
{
	return(0);
}

/*
 * Receive data
 */
static int
ngipi_rcvdata(hook_p hook, item_p item)
{
	struct mbuf *m;

	NGI_GET_M(item, m);
	NG_FREE_ITEM(item);
	if (curthread->td_ng_outbound)
		netisr_queue(NETISR_IP, m);
	else {
		struct epoch_tracker et;

		NET_EPOCH_ENTER(et);
		netisr_dispatch(NETISR_IP, m);
		NET_EPOCH_EXIT(et);
	}
	return 0;
}

/*
 * Hook disconnection
 */
static int
ngipi_disconnect(hook_p hook)
{
	if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
		ng_rmnode_self(NG_HOOK_NODE(hook));
	return (0);
}