3 Packet assembly code, originally contributed by Archie Cobbs. */
6 * Copyright (c) 1996-2002 Internet Software Consortium.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of The Internet Software Consortium nor the names
19 * of its contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
23 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
24 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
27 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
29 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
30 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
31 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
32 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
33 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * This software has been written for the Internet Software Consortium
37 * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
38 * To learn more about the Internet Software Consortium, see
39 * ``http://www.isc.org/''. To learn more about Vixie Enterprises,
40 * see ``http://www.vix.com''. To learn more about Nominum, Inc., see
41 * ``http://www.nominum.com''.
45 static char copyright[] =
46 "$Id: ethernet.c,v 1.6.2.2 2002/11/17 02:26:57 dhankins Exp $ Copyright (c) 1996-2002 The Internet Software Consortium. All rights reserved.\n";
51 #if defined (PACKET_ASSEMBLY) || defined (PACKET_DECODING)
52 #include "includes/netinet/if_ether.h"
53 #endif /* PACKET_ASSEMBLY || PACKET_DECODING */
55 #if defined (PACKET_ASSEMBLY)
56 /* Assemble an hardware header... */
58 void assemble_ethernet_header (interface, buf, bufix, to)
59 struct interface_info *interface;
64 struct isc_ether_header eh;
66 if (to && to -> hlen == 7) /* XXX */
67 memcpy (eh.ether_dhost, &to -> hbuf [1],
68 sizeof eh.ether_dhost);
70 memset (eh.ether_dhost, 0xff, sizeof (eh.ether_dhost));
71 if (interface -> hw_address.hlen - 1 == sizeof (eh.ether_shost))
72 memcpy (eh.ether_shost, &interface -> hw_address.hbuf [1],
73 sizeof (eh.ether_shost));
75 memset (eh.ether_shost, 0x00, sizeof (eh.ether_shost));
77 eh.ether_type = htons (ETHERTYPE_IP);
79 memcpy (&buf [*bufix], &eh, ETHER_HEADER_SIZE);
80 *bufix += ETHER_HEADER_SIZE;
82 #endif /* PACKET_ASSEMBLY */
84 #ifdef PACKET_DECODING
85 /* Decode a hardware header... */
87 ssize_t decode_ethernet_header (interface, buf, bufix, from)
88 struct interface_info *interface;
91 struct hardware *from;
93 struct isc_ether_header eh;
95 memcpy (&eh, buf + bufix, ETHER_HEADER_SIZE);
97 #ifdef USERLAND_FILTER
98 if (ntohs (eh.ether_type) != ETHERTYPE_IP)
101 memcpy (&from -> hbuf [1], eh.ether_shost, sizeof (eh.ether_shost));
102 from -> hbuf [0] = ARPHRD_ETHER;
103 from -> hlen = (sizeof eh.ether_shost) + 1;
105 return ETHER_HEADER_SIZE;
107 #endif /* PACKET_DECODING */