tcpreplay/utils.c

/* $Id: utils.c 767 2004-10-06 12:48:49Z aturner $ */

/*
 * Copyright (c) 2001-2004 Aaron Turner, Matt Bing.
 * 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.
 * 3. Neither the names of the copyright owners nor the names of its
 *    contributors may be used to endorse or promote products derived from *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``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 AUTHORS OR COPYRIGHT HOLDERS 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 <sys/types.h>
#include <regex.h>
#include "config.h"
#include "tcpreplay.h"
#include "utils.h"
#include "err.h"

extern int maxpacket;
extern struct options options;

int
read_hexstring(char *l2string, char *hex, int hexlen)
{
    int numbytes = 0;
    unsigned int value;
    char *l2byte;
    u_char databyte;
    char *token = NULL;

    if (hexlen <= 0)
        errx(1, "Hex buffer must be > 0");

    memset(hex, '\0', hexlen);

    /* data is hex, comma seperated, byte by byte */

    /* get the first byte */
    l2byte = strtok_r(l2string, ",", &token);
    sscanf(l2byte, "%x", &value);
    if (value > 0xff)
        errx(1, "Invalid hex byte passed to -2: %s", l2byte);
    databyte = (u_char) value;
    memcpy(&hex[numbytes], &databyte, 1);

    /* get remaining bytes */
    while ((l2byte = strtok_r(NULL, ",", &token)) != NULL) {
        numbytes++;
        if (numbytes + 1 > hexlen) {
            warnx("Hex buffer too small for data- skipping data");
            return (++numbytes);
        }
        sscanf(l2byte, "%x", &value);
        if (value > 0xff)
            errx(1, "Invalid hex byte passed to -2: %s", l2byte);
        databyte = (u_char) value;
        memcpy(&hex[numbytes], &databyte, 1);
    }

    numbytes++;

    dbg(1, "Read %d bytes of layer 2 data", numbytes);
    return (numbytes);
}

/* whorishly appropriated from fragroute-1.2 */

int
argv_create(char *p, int argc, char *argv[])
{
    int i;

    for (i = 0; i < argc - 1; i++) {
        while (*p != '\0' && isspace((int)*p))
            *p++ = '\0';

        if (*p == '\0')
            break;
        argv[i] = p;

        while (*p != '\0' && !isspace((int)*p))
            p++;
    }
    p[0] = '\0';
    argv[i] = NULL;

    return (i);
}

/*
 * converts a string representation of a MAC address, based on 
 * non-portable ether_aton() 
 */
void
mac2hex(const char *mac, char *dst, int len)
{
    int i;
    long l;
    char *pp;

    if (len < 6)
        return;

    while (isspace(*mac))
        mac++;

    /* expect 6 hex octets separated by ':' or space/NUL if last octet */
    for (i = 0; i < 6; i++) {
        l = strtol(mac, &pp, 16);
        if (pp == mac || l > 0xFF || l < 0)
            return;
        if (!(*pp == ':' || (i == 5 && (isspace(*pp) || *pp == '\0'))))
            return;
        dst[i] = (u_char) l;
        mac = pp + 1;
    }
}




/*
 * returns a pointer to the layer 4 header which is just beyond the IP header
 */
void *
get_layer4(ip_hdr_t * ip_hdr)
{
    void *ptr;
    ptr = (u_int32_t *) ip_hdr + ip_hdr->ip_hl;
    return ((void *)ptr);
}