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/* packet.c
Packet assembly code, originally contributed by Archie Cobbs. */
/*
* Copyright (c) 1996-1999 Internet Software Consortium.
* Use is subject to license terms which appear in the file named
* ISC-LICENSE that should have accompanied this file when you
* received it. If a file named ISC-LICENSE did not accompany this
* file, or you are not sure the one you have is correct, you may
* obtain an applicable copy of the license at:
*
* http://www.isc.org/isc-license-1.0.html.
*
* This file is part of the ISC DHCP distribution. The documentation
* associated with this file is listed in the file DOCUMENTATION,
* included in the top-level directory of this release.
*
* Support and other services are available for ISC products - see
* http://www.isc.org for more information.
*/
#ifndef lint
static char copyright[] =
"$Id: ethernet.c,v 1.2 1999/10/07 06:35:42 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;
unsigned *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;
unsigned 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 */
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