/* ethernet.c Packet assembly code, originally contributed by Archie Cobbs. */ /* * Copyright (c) 1996-2000 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 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''. */ #ifndef lint static char copyright[] = "$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"; #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; unsigned *bufix; struct hardware *to; { struct isc_ether_header eh; if (to && to -> hlen == 7) /* XXX */ memcpy (eh.ether_dhost, &to -> hbuf [1], sizeof eh.ether_dhost); else memset (eh.ether_dhost, 0xff, sizeof (eh.ether_dhost)); if (interface -> hw_address.hlen - 1 == sizeof (eh.ether_shost)) memcpy (eh.ether_shost, &interface -> hw_address.hbuf [1], 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; } #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 isc_ether_header eh; memcpy (&eh, buf + bufix, ETHER_HEADER_SIZE); #ifdef USERLAND_FILTER if (ntohs (eh.ether_type) != ETHERTYPE_IP) return -1; #endif memcpy (&from -> hbuf [1], eh.ether_shost, sizeof (eh.ether_shost)); from -> hbuf [0] = ARPHRD_ETHER; from -> hlen = (sizeof eh.ether_shost) + 1; return ETHER_HEADER_SIZE; } #endif /* PACKET_DECODING */