githubmirror/libnet

src/libnet_init.c
280 строк6 KB
Joachim Wiberg
libnet_destroy(): verify l->device is a pointer before calling free
28 дек 2022, 16:11
28 дек 2022, 16:11ce65276
/*
 *  $Id: libnet_init.c,v 1.17 2004/03/16 18:40:59 mike Exp $
 *
 *  libnet
 *  libnet_init.c - Initilization routines.
 *
 *  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.
 *
 */

#include "common.h"

libnet_t *
libnet_init(int injection_type, const char *device, char *err_buf)
{
    libnet_t *l = NULL;

#if defined(__WIN32__)
    WSADATA wsaData;

    if ((WSAStartup(0x0202, &wsaData)) != 0)
    {
        snprintf(err_buf, LIBNET_ERRBUF_SIZE, 
                "%s(): unable to initialize winsock 2", __func__);
        goto bad;
    }
#endif

    l = (libnet_t *)malloc(sizeof (libnet_t));
    if (l == NULL)
    {
        snprintf(err_buf, LIBNET_ERRBUF_SIZE, "%s(): malloc(): %s", __func__,
                strerror(errno));
        goto bad;
    }
	
    memset(l, 0, sizeof (*l));

    l->injection_type   = injection_type;
    l->ptag_state       = LIBNET_PTAG_INITIALIZER;
    l->device           = (device ? strdup(device) : NULL);
    l->fd               = -1;

    strncpy(l->label, LIBNET_LABEL_DEFAULT, LIBNET_LABEL_SIZE);
    l->label[LIBNET_LABEL_SIZE - 1] = '\0';

    switch (l->injection_type)
    {
        case LIBNET_NONE:
            break;
        case LIBNET_LINK:
        case LIBNET_LINK_ADV:
            if (libnet_select_device(l) == -1)
            {
                snprintf(err_buf, LIBNET_ERRBUF_SIZE, "%s", l->err_buf);
		goto bad;
            }
            if (libnet_open_link(l) == -1)
            {
                snprintf(err_buf, LIBNET_ERRBUF_SIZE, "%s", l->err_buf);
                goto bad;
            }
            break;
        case LIBNET_RAW4:
        case LIBNET_RAW4_ADV:
            if (libnet_open_raw4(l) == -1)
            {
                snprintf(err_buf, LIBNET_ERRBUF_SIZE, "%s", l->err_buf);
                goto bad;
            }
            break;
        case LIBNET_RAW6:
        case LIBNET_RAW6_ADV:
            if (libnet_open_raw6(l) == -1)
            {
                snprintf(err_buf, LIBNET_ERRBUF_SIZE, "%s", l->err_buf);
                goto bad;
            }
            break;
        default:
            snprintf(err_buf, LIBNET_ERRBUF_SIZE,
                    "%s(): unsupported injection type", __func__);
            goto bad;
            break;
    }

    return (l);

bad:
    if (l)
    {
        libnet_destroy(l);
    }
    return (NULL);
}

void
libnet_destroy(libnet_t *l)
{
    if (l)
    {
        if (l->fd != -1)
            close(l->fd);
        if (l->device)
            free(l->device);
        libnet_clear_packet(l);
        free(l);
    }
}

void
libnet_clear_packet(libnet_t *l)
{
    libnet_pblock_t *p;

    if (!l)
    {
        return;
    }

    while ((p = l->protocol_blocks))
    {
        libnet_pblock_delete(l, p);
    }

    /* All pblocks are deleted, so start the tag count over from 1. */
    l->ptag_state = 0;
}

void
libnet_stats(libnet_t *l, struct libnet_stats *ls)
{
    if (l == NULL)
    { 
        return;
    }

    ls->packets_sent  = l->stats.packets_sent;
    ls->packet_errors = l->stats.packet_errors;
    ls->bytes_written = l->stats.bytes_written;
}

int
libnet_getfd(libnet_t *l)
{
    if (l == NULL)
    { 
        return (-1);
    } 

    return (int)(l->fd);
}

#ifdef SO_SNDBUF
int
libnet_setfd_max_sndbuf(libnet_t *l, int max_bytes)
{
    if (l == NULL)
        return (-1);

    /* Try to set the buffer size to max_bytes */
    if (setsockopt(l->fd, SOL_SOCKET, SO_SNDBUF, &max_bytes, sizeof(max_bytes)) < 0)
    {
        snprintf(l->err_buf, LIBNET_ERRBUF_SIZE,
                    "%s(): set SO_SNDBUF failed: %s",
                    __func__, strerror(errno));
        return (-1);
    }

    return (0);
}
#endif /* SO_SNDBUF */

const char *
libnet_getdevice(libnet_t *l)
{
    if (l == NULL)
    { 
        return (NULL);
    }

    return (l->device);
}

uint8_t *
libnet_getpbuf(libnet_t *l, libnet_ptag_t ptag)
{
    libnet_pblock_t *p;

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

    p = libnet_pblock_find(l, ptag);
    if (p == NULL)
    {
        /* err msg set in libnet_pblock_find() */
        return (NULL);
    }
    else
    {
        return (p->buf);
    }
}

uint32_t
libnet_getpbuf_size(libnet_t *l, libnet_ptag_t ptag)
{
    libnet_pblock_t *p;

    if (l == NULL)
    { 
        return (0);
    } 

    p = libnet_pblock_find(l, ptag);
    if (p == NULL)
    {
        /* err msg set in libnet_pblock_find() */
        return (0);
    }
    else
    {
        return (p->b_len);
    }
}

uint32_t
libnet_getpacket_size(libnet_t *l)
{
    /* Why doesn't this return l->total_size? */
    libnet_pblock_t *p;
    uint32_t n;

    if (l == NULL)
    { 
        return (0);
    } 

    n = 0;
    p = l->protocol_blocks;
    if (p)
    {
        for (; p; p = p->next)
        {
            n += p->b_len;
        }
    }
    return (n);
}

/**
 * Local Variables:
 *  indent-tabs-mode: nil
 *  c-file-style: "stroustrup"
 * End:
 */