/*

 *  $Id: tcp1.c,v 1.6 2004/03/01 20:26:12 mike Exp $

 *

 *  libnet 1.1

 *  Build a TCP packet

 *

 *  Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com>

 *  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"

#ifdef __WIN32__

#include "../include/win32/getopt.h"

#endif

int

main(int argc, char *argv[])

{

    int c;

    char *cp;

    libnet_t *l;

    libnet_ptag_t t;

    char *payload;

    u_short payload_s;

    u_long src_ip, dst_ip;

    u_short src_prt, dst_prt;

    char errbuf[LIBNET_ERRBUF_SIZE];

    printf("libnet 1.1 packet shaping: TCP + options[link]\n");

    /*

     *  Initialize the library.  Root priviledges are required.

     */

    l = libnet_init(

            LIBNET_LINK,                            /* injection type */

            NULL,                                   /* network interface */

            errbuf);                                /* error buffer */

    if (l == NULL)

    {

        fprintf(stderr, "libnet_init() failed: %s", errbuf);

        exit(EXIT_FAILURE); 

    }

    src_ip  = 0;

    dst_ip  = 0;

    src_prt = 0;

    dst_prt = 0;

    payload = NULL;

    payload_s = 0;

    while ((c = getopt(argc, argv, "d:s:p:")) != EOF)

    {

        switch (c)

        {

            /*

             *  We expect the input to be of the form `ip.ip.ip.ip.port`.  We

             *  point cp to the last dot of the IP address/port string and

             *  then seperate them with a NULL byte.  The optarg now points to

             *  just the IP address, and cp points to the port.

             */

            case 'd':

                if (!(cp = strrchr(optarg, '.')))

                {

                    usage(argv[0]);

                }

                *cp++ = 0;

                dst_prt = (u_short)atoi(cp);

                if ((dst_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)

                {

                    fprintf(stderr, "Bad destination IP address: %s\n", optarg);

                    exit(EXIT_FAILURE);

                }

                break;

            case 's':

                if (!(cp = strrchr(optarg, '.')))

                {

                    usage(argv[0]);

                }

                *cp++ = 0;

                src_prt = (u_short)atoi(cp);

                if ((src_ip = libnet_name2addr4(l, optarg, LIBNET_RESOLVE)) == -1)

                {

                    fprintf(stderr, "Bad source IP address: %s\n", optarg);

                    exit(EXIT_FAILURE);

                }

                break;

            case 'p':

                payload = optarg;

                payload_s = strlen(payload);

                break;

            default:

                exit(EXIT_FAILURE);

        }

    }

    if (!src_ip || !src_prt || !dst_ip || !dst_prt)

    {

        usage(argv[0]);

        exit(EXIT_FAILURE);

    }

    t = libnet_build_tcp_options(

        (uint8_t*)"\003\003\012\001\002\004\001\011\010\012\077\077\077\077\000\000\000\000\000\000",

        20,

        l,

        0);

    if (t == -1)

    {

        fprintf(stderr, "Can't build TCP options: %s\n", libnet_geterror(l));

        goto bad;

    }

    t = libnet_build_tcp(

        src_prt,                                    /* source port */

        dst_prt,                                    /* destination port */

        0x01010101,                                 /* sequence number */

        0x02020202,                                 /* acknowledgement num */

        TH_SYN,                                     /* control flags */

        32767,                                      /* window size */

        0,                                          /* checksum */

        10,                                          /* urgent pointer */

        LIBNET_TCP_H + 20 + payload_s,              /* TCP packet size */

	(uint8_t*)payload,                         /* payload */

        payload_s,                                  /* payload size */

        l,                                          /* libnet handle */

        0);                                         /* libnet id */

    if (t == -1)

    {

        fprintf(stderr, "Can't build TCP header: %s\n", libnet_geterror(l));

        goto bad;

    }

    t = libnet_build_ipv4(

        LIBNET_IPV4_H + LIBNET_TCP_H + 20 + payload_s,/* length */

      	0,                                          /* TOS */

        242,                                        /* IP ID */

        0,                                          /* IP Frag */

        64,                                         /* TTL */

        IPPROTO_TCP,                                /* protocol */

        0,                                          /* checksum */

        src_ip,                                     /* source IP */

        dst_ip,                                     /* destination IP */

        NULL,                                       /* payload */

        0,                                          /* payload size */

        l,                                          /* libnet handle */

        0);                                         /* libnet id */

    if (t == -1)

    {

        fprintf(stderr, "Can't build IP header: %s\n", libnet_geterror(l));

        goto bad;

    }

    t = libnet_build_ethernet(

        enet_dst,                                   /* ethernet destination */

        enet_src,                                   /* ethernet source */

        ETHERTYPE_IP,                               /* protocol type */

        NULL,                                       /* payload */

        0,                                          /* payload size */

        l,                                          /* libnet handle */

        0);                                         /* libnet id */

    if (t == -1)

    {

        fprintf(stderr, "Can't build ethernet header: %s\n", libnet_geterror(l));

        goto bad;

    }

    /*

     *  Write it to the wire.

     */

    c = libnet_write(l);

    if (c == -1)

    {

        fprintf(stderr, "Write error: %s\n", libnet_geterror(l));

        goto bad;

   }

   else

   {

       fprintf(stderr, "Wrote %d byte TCP packet; check the wire.\n", c);

   }

    libnet_destroy(l);

    return (EXIT_SUCCESS);

bad:

    libnet_destroy(l);

    return (EXIT_FAILURE);

}

void

usage(char *name)

{

    fprintf(stderr,

        "usage: %s -s source_ip.source_port -d destination_ip.destination_port"

        " [-p payload]\n",

        name);

}

#if defined(__WIN32__)

#include <../include/win32/getopt.h>

#include <winsock2.h>

#include <ws2tcpip.h>

#endif  /* __WIN32__ */

/* EOF */