freebsd-dev/contrib/isc-dhcp/common/ethernet.c

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1999-06-23 23:40:02 +00:00
/* packet.c
Packet assembly code, originally contributed by Archie Cobbs. */
/*
* Copyright (c) 1995, 1996 The Internet Software Consortium.
* 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. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
* CONTRIBUTORS ``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 INTERNET SOFTWARE CONSORTIUM OR
* CONTRIBUTORS 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.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#ifndef lint
static char copyright[] =
"$Id: ethernet.c,v 1.1.2.1 1999/05/27 17:35:47 mellon Exp $ Copyright (c) 1996 The Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
#if defined (PACKET_ASSEMBLY) || defined (PACKET_DECODING)
#include "includes/netinet/if_ether.h"
#endif /* PACKET_ASSEMBLY || PACKET_DECODING */
#if defined (PACKET_ASSEMBLY)
/* Assemble an hardware header... */
/* XXX currently only supports ethernet; doesn't check for other types. */
void assemble_ethernet_header (interface, buf, bufix, to)
struct interface_info *interface;
unsigned char *buf;
int *bufix;
struct hardware *to;
{
struct ether_header eh;
if (to && to -> hlen == 6) /* XXX */
memcpy (eh.ether_dhost, to -> haddr, sizeof eh.ether_dhost);
else
memset (eh.ether_dhost, 0xff, sizeof (eh.ether_dhost));
if (interface -> hw_address.hlen == sizeof (eh.ether_shost))
memcpy (eh.ether_shost, interface -> hw_address.haddr,
sizeof (eh.ether_shost));
else
memset (eh.ether_shost, 0x00, sizeof (eh.ether_shost));
#ifdef BROKEN_FREEBSD_BPF /* Fixed in FreeBSD 2.2 */
eh.ether_type = ETHERTYPE_IP;
#else
eh.ether_type = htons (ETHERTYPE_IP);
#endif
memcpy (&buf [*bufix], &eh, sizeof eh);
*bufix += sizeof eh;
}
#endif /* PACKET_ASSEMBLY */
#ifdef PACKET_DECODING
/* Decode a hardware header... */
ssize_t decode_ethernet_header (interface, buf, bufix, from)
struct interface_info *interface;
unsigned char *buf;
int bufix;
struct hardware *from;
{
struct ether_header eh;
memcpy (&eh, buf + bufix, sizeof eh);
#ifdef USERLAND_FILTER
if (ntohs (eh.ether_type) != ETHERTYPE_IP)
return -1;
#endif
memcpy (from -> haddr, eh.ether_shost, sizeof (eh.ether_shost));
from -> htype = ARPHRD_ETHER;
from -> hlen = sizeof eh.ether_shost;
return sizeof eh;
}
#endif /* PACKET_DECODING */