libnet_build_ospf.c

来自「Libnet is a generic networking API that 」· C语言 代码 · 共 616 行 · 第 1/2 页

/*
 *  $Id: libnet_build_ospf.c,v 1.1.1.1 2002/09/16 12:58:06 robertol Exp $
 *
 *  libnet
 *  libnet_build_ospf.c - OSPF packet assembler
 *
 *  Copyright (c) 1998 - 2002 Mike D. Schiffman <[e-mail]>
 *  All rights reserved.
 *
 *  Copyright (c) 1999, 2000 Andrew Reiter <[e-mail]>
 *  Bindview Development
 *
 * 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 "../include/libnet.h"

libnet_ptag_t
libnet_build_ospfv2(u_short len, u_char type, u_long rtr_id, u_long area_id,
            u_short sum, u_short autype, u_char *payload, u_long payload_s, 
            libnet_t *l, libnet_ptag_t ptag)
{
    u_long n;
    u_short h;
    libnet_pblock_t *p;
    struct libnet_ospf_hdr ospf_hdr;
    
    memset(&ospf_hdr, 0, sizeof(ospf_hdr));

    if (l == NULL)
    { 
        return (-1);
    } 
 
    n = LIBNET_OSPF_H + payload_s;
    h = LIBNET_OSPF_H + payload_s + len;

    /*
     *  Find the existing protocol block if a ptag is specified, or create
     *  a new one.
     */
    p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_OSPF_H);
    if (p == NULL)
    {
        return (-1);
    }
    
    ospf_hdr.ospf_v               = 2;              /* OSPF version 2 */
    ospf_hdr.ospf_type            = type;           /* Type of pkt */
    ospf_hdr.ospf_len             = htons(h);       /* Pkt len */
    ospf_hdr.ospf_rtr_id.s_addr   = htonl(rtr_id);  /* Router ID */
    ospf_hdr.ospf_area_id.s_addr  = htonl(area_id); /* Area ID */
    ospf_hdr.ospf_cksum           = sum;
    ospf_hdr.ospf_auth_type       = htons(autype);  /* Type of auth */

    n = libnet_pblock_append(l, p, (u_char *)&ospf_hdr, LIBNET_OSPF_H);
    if (n == -1)
    {
        goto bad;
    }
 
    if (payload && payload_s)
    {
        n = libnet_pblock_append(l, p, payload, payload_s);
        if (n == -1)
        {
            goto bad;
        }
    }

    if (sum == 0)
    {
        /*
         *  If checksum is zero, by default libnet will compute a checksum
         *  for the user.  The programmer can override this by calling
         *  libnet_toggle_checksum(l, ptag, 1);
         */
        libnet_pblock_setflags(p, LIBNET_PBLOCK_DO_CHECKSUM);
    }
    return (ptag ? ptag : libnet_pblock_update(l, p, h, LIBNET_PBLOCK_OSPF_H));
bad:
    libnet_pblock_free(p);
    return (-1);
}


libnet_ptag_t
libnet_build_ospfv2_hello(u_long netmask, u_short interval, u_char opts, 
            u_char priority, u_int dead_int, u_long des_rtr, u_long bkup_rtr,
            u_long neighbor, u_char *payload, u_long payload_s, libnet_t *l,
            libnet_ptag_t ptag)
{
    u_long n;
    u_short h;
    libnet_pblock_t *p;
    struct libnet_ospf_hello_hdr hello_hdr;

    if (l == NULL)
    { 
        return (-1);
    } 

    n = LIBNET_OSPF_HELLO_H + payload_s;
    h = 0;

    /*
     *  Find the existing protocol block if a ptag is specified, or create
     *  a new one.
     */
    p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_OSPF_HELLO_H);
    if (p == NULL)
    {
        return (-1);
    }
    
    hello_hdr.hello_nmask.s_addr    = htonl(netmask);  /* Netmask */
    hello_hdr.hello_intrvl          = htons(interval);	/* # seconds since last packet sent */
    hello_hdr.hello_opts            = opts;     /* OSPF_* options */
    hello_hdr.hello_rtr_pri         = priority; /* If 0, can't be backup */
    hello_hdr.hello_dead_intvl      = htonl(dead_int); /* Time til router is deemed down */
    hello_hdr.hello_des_rtr.s_addr  = htonl(des_rtr);	/* Networks designated router */
    hello_hdr.hello_bkup_rtr.s_addr = htonl(bkup_rtr); /* Networks backup router */
    hello_hdr.hello_nbr.s_addr      = htonl(neighbor);

    n = libnet_pblock_append(l, p, (u_char *)&hello_hdr, LIBNET_OSPF_HELLO_H);
    if (n == -1)
    {
        goto bad;
    }
 
    if (payload && payload_s)
    {
        n = libnet_pblock_append(l, p, payload, payload_s);
        if (n == -1)
        {
            goto bad;
        }
    }
 
    return (ptag ? ptag : libnet_pblock_update(l, p, h, LIBNET_PBLOCK_OSPF_HELLO_H));
bad:
    libnet_pblock_free(p);
    return (-1);
}


libnet_ptag_t
libnet_build_ospfv2_dbd(u_short dgram_len, u_char opts, u_char type,
            u_int seqnum, u_char *payload, u_long payload_s, libnet_t *l,
            libnet_ptag_t ptag)
{
    u_long n;
    u_short h;
    libnet_pblock_t *p;
    struct libnet_dbd_hdr dbd_hdr;

    if (l == NULL)
    { 
        return (-1);
    } 

    n = LIBNET_OSPF_DBD_H + payload_s;
    h = 0;

    /*
     *  Find the existing protocol block if a ptag is specified, or create
     *  a new one.
     */
    p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_OSPF_DBD_H);
    if (p == NULL)
    {
        return (-1);
    }
    
    dbd_hdr.dbd_mtu_len	= htons(dgram_len); /* Max length of IP packet IF can use */
    dbd_hdr.dbd_opts    = opts;	            /* OSPF_* options */
    dbd_hdr.dbd_type    = type;	            /* Type of exchange occuring */
    dbd_hdr.dbd_seq     = htonl(seqnum);    /* DBD sequence number */

    n = libnet_pblock_append(l, p, (u_char *)&dbd_hdr, LIBNET_OSPF_DBD_H);
    if (n == -1)
    {
        goto bad;
    }
 
    if (payload && payload_s)
    {
        n = libnet_pblock_append(l, p, payload, payload_s);
        if (n == -1)
        {
            goto bad; 
        }
    }

    return (ptag ? ptag : libnet_pblock_update(l, p, h, LIBNET_PBLOCK_OSPF_DBD_H));
bad:
    libnet_pblock_free(p);
    return (-1);
}


libnet_ptag_t
libnet_build_ospfv2_lsr(u_int type, u_int lsid, u_long advrtr, u_char 
*payload,
            u_long payload_s, libnet_t *l, libnet_ptag_t ptag)
{
    u_long n;
    u_short h;
    libnet_pblock_t *p;
    struct libnet_lsr_hdr lsr_hdr;

    if (l == NULL)
    { 
        return (-1);
    } 

    n = LIBNET_OSPF_LSR_H + payload_s;
    h = 0;

    /*
     *  Find the existing protocol block if a ptag is specified, or create
     *  a new one.
     */
    p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_OSPF_LSR_H);
    if (p == NULL)
    {
        return (-1);
    }

    lsr_hdr.lsr_type         = htonl(type);     /* Type of LS being requested */
    lsr_hdr.lsr_lsid	     = htonl(lsid);     /* Link State ID */
    lsr_hdr.lsr_adrtr.s_addr = htonl(advrtr);   /* Advertising router */

    n = libnet_pblock_append(l, p, (u_char *)&lsr_hdr, LIBNET_OSPF_LSR_H);
    if (n == -1)
    {
        goto bad;
    }
 
    if (payload && payload_s)
    {
        n = libnet_pblock_append(l, p, payload, payload_s);
        if (n == -1)
        {
            goto bad;
        }
    }

    return (ptag ? ptag : libnet_pblock_update(l, p, h, LIBNET_PBLOCK_OSPF_LSR_H));
bad:
    libnet_pblock_free(p);
    return (-1);
}


libnet_ptag_t
libnet_build_ospfv2_lsu(u_int num, u_char *payload, u_long payload_s,
            libnet_t *l, libnet_ptag_t ptag)
{
    u_long n;
    u_short h;
    libnet_pblock_t *p;
    struct libnet_lsu_hdr lh_hdr;

    if (l == NULL)
    { 
        return (-1);
    } 

    n = LIBNET_OSPF_LSU_H + payload_s;
    h = 0;

    /*
     *  Find the existing protocol block if a ptag is specified, or create
     *  a new one.
     */
    p = libnet_pblock_probe(l, ptag, n, LIBNET_PBLOCK_OSPF_LSU_H);
    if (p == NULL)
    {
        return (-1);
    }

    lh_hdr.lsu_num = htonl(num);   /* Number of LSAs that will be bcasted */

    n = libnet_pblock_append(l, p, (u_char *)&lh_hdr, LIBNET_OSPF_LSU_H);