/* * $Id: arp.c,v 1.5 2004/01/28 19:45:00 mike Exp $ * * libnet 1.1 * Build an ARP packet * * Copyright (c) 1998 - 2004 Mike D. Schiffman * 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. * */ #if (HAVE_CONFIG_H) #include "../include/config.h" #endif #include "./libnet_test.h" int main(int argc, char *argv[]) { int c; uint32_t i; libnet_t *l; libnet_ptag_t t; char *device = NULL; uint8_t *packet; uint32_t packet_s; char errbuf[LIBNET_ERRBUF_SIZE]; printf("libnet 1.1 packet shaping: ARP[link -- autobuilding ethernet]\n"); if (argc > 1) { device = argv[1]; } l = libnet_init( LIBNET_LINK_ADV, /* injection type */ device, /* network interface */ errbuf); /* errbuf */ if (l == NULL) { fprintf(stderr, "%s", errbuf); exit(EXIT_FAILURE); } else /* * Build the packet, remmebering that order IS important. We must * build the packet from lowest protocol type on up as it would * appear on the wire. So for our ARP packet: * * ------------------------------------------- * | Ethernet | ARP | * ------------------------------------------- * ^ ^ * |------------------ | * libnet_build_ethernet()--| | * | * libnet_build_arp()-----------| */ i = libnet_get_ipaddr4(l); t = libnet_autobuild_arp( ARPOP_REPLY, /* operation type */ enet_src, /* sender hardware addr */ (uint8_t *)&i, /* sender protocol addr */ enet_dst, /* target hardware addr */ (uint8_t *)&i, /* target protocol addr */ l); /* libnet context */ if (t == -1) { fprintf(stderr, "Can't build ARP header: %s\n", libnet_geterror(l)); goto bad; } t = libnet_autobuild_ethernet( enet_dst, /* ethernet destination */ ETHERTYPE_ARP, /* protocol type */ l); /* libnet handle */ if (t == -1) { fprintf(stderr, "Can't build ethernet header: %s\n", libnet_geterror(l)); goto bad; } if (libnet_adv_cull_packet(l, &packet, &packet_s) == -1) { fprintf(stderr, "%s", libnet_geterror(l)); } else { fprintf(stderr, "packet size: %d\n", packet_s); libnet_adv_free_packet(l, packet); } c = libnet_write(l); if (c == -1) { fprintf(stderr, "Write error: %s\n", libnet_geterror(l)); goto bad; } else { fprintf(stderr, "Wrote %d byte ARP packet from context \"%s\"; " "check the wire.\n", c, libnet_cq_getlabel(l)); } libnet_destroy(l); return (EXIT_SUCCESS); bad: libnet_destroy(l); return (EXIT_FAILURE); } /* EOF */