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

108 lines
3.8 KiB
C
Raw Normal View History

2002-02-19 11:04:34 +00:00
/* ethernet.c
1999-06-23 23:40:02 +00:00
Packet assembly code, originally contributed by Archie Cobbs. */
/*
2002-02-19 11:04:34 +00:00
* Copyright (c) 1996-2000 Internet Software Consortium.
1999-06-23 23:40:02 +00:00
* 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
2002-02-19 11:04:34 +00:00
* by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
* To learn more about the Internet Software Consortium, see
* ``http://www.isc.org/''. To learn more about Vixie Enterprises,
* see ``http://www.vix.com''. To learn more about Nominum, Inc., see
* ``http://www.nominum.com''.
1999-06-23 23:40:02 +00:00
*/
#ifndef lint
static char copyright[] =
2002-02-19 11:04:34 +00:00
"$Id: ethernet.c,v 1.6.2.1 2001/06/14 19:15:27 mellon Exp $ Copyright (c) 1996-2000 The Internet Software Consortium. All rights reserved.\n";
1999-06-23 23:40:02 +00:00
#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... */
void assemble_ethernet_header (interface, buf, bufix, to)
struct interface_info *interface;
unsigned char *buf;
2002-02-19 11:04:34 +00:00
unsigned *bufix;
1999-06-23 23:40:02 +00:00
struct hardware *to;
{
2002-02-19 11:04:34 +00:00
struct isc_ether_header eh;
1999-06-23 23:40:02 +00:00
2002-02-19 11:04:34 +00:00
if (to && to -> hlen == 7) /* XXX */
memcpy (eh.ether_dhost, &to -> hbuf [1],
sizeof eh.ether_dhost);
1999-06-23 23:40:02 +00:00
else
memset (eh.ether_dhost, 0xff, sizeof (eh.ether_dhost));
2002-02-19 11:04:34 +00:00
if (interface -> hw_address.hlen - 1 == sizeof (eh.ether_shost))
memcpy (eh.ether_shost, &interface -> hw_address.hbuf [1],
1999-06-23 23:40:02 +00:00
sizeof (eh.ether_shost));
else
memset (eh.ether_shost, 0x00, sizeof (eh.ether_shost));
eh.ether_type = htons (ETHERTYPE_IP);
memcpy (&buf [*bufix], &eh, ETHER_HEADER_SIZE);
*bufix += ETHER_HEADER_SIZE;
1999-06-23 23:40:02 +00:00
}
#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;
2002-02-19 11:04:34 +00:00
unsigned bufix;
1999-06-23 23:40:02 +00:00
struct hardware *from;
{
2002-02-19 11:04:34 +00:00
struct isc_ether_header eh;
1999-06-23 23:40:02 +00:00
memcpy (&eh, buf + bufix, ETHER_HEADER_SIZE);
1999-06-23 23:40:02 +00:00
#ifdef USERLAND_FILTER
if (ntohs (eh.ether_type) != ETHERTYPE_IP)
return -1;
#endif
2002-02-19 11:04:34 +00:00
memcpy (&from -> hbuf [1], eh.ether_shost, sizeof (eh.ether_shost));
from -> hbuf [0] = ARPHRD_ETHER;
from -> hlen = (sizeof eh.ether_shost) + 1;
1999-06-23 23:40:02 +00:00
2002-02-19 11:04:34 +00:00
return ETHER_HEADER_SIZE;
1999-06-23 23:40:02 +00:00
}
#endif /* PACKET_DECODING */