Linux Cubed Series 7: Sunsite/Linux Cubed Series 7 - Sunsite Vol 1.iso/system/network/manageme/tcpdump-.7/tcpdump-/tcpdump-richard-1.7/libpcap-0.0/pcap.c

C/C++ Source or Header | 1995-06-09 | 4.4 KB | 201 lines

/*
 * Copyright (c) 1993, 1994
 *    The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    This product includes software developed by the Computer Systems
 *    Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

#ifndef lint
static char rcsid[] =
    "@(#) $Header: pcap.c,v 1.12 94/06/12 14:32:23 leres Exp $ (LBL)";
#endif

#include <sys/types.h>

#include <unistd.h>
#if __STDC__
#include <stdlib.h>
#endif

#include "pcap-int.h"

int
pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
    if (p->rf.rfile != NULL)
        return (pcap_read_offline(p, cnt, callback, user));
    else
        return (pcap_read_live(p, cnt, callback, user));
}

int
pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
    for (;;) {
        int n = pcap_dispatch(p, cnt, callback, user);
        if (n < 0)
            return (n);
        if (cnt > 0) {
            cnt -= n;
            if (cnt <= 0)
                return (0);
        }
        /* return always in case we have been reading from a file */
        if (p->rf.rfile != NULL)
            return (0);
    }
}

struct singleton {
    struct pcap_hdr *hdr;
    const u_char *pkt;
};


static void
pcap_oneshot(u_char *userData, const struct pcap_hdr *h, const u_char *pkt)
{
    struct singleton *sp = (struct singleton *)userData;
    *sp->hdr = *h;
    sp->pkt = pkt;
}

const u_char *
pcap_next(pcap_t *p, struct pcap_hdr *h)
{
    struct singleton s;

    s.hdr = h;
    if (pcap_dispatch(p, 1, pcap_oneshot, (u_char*)&s) < 0)
        return (0);
    return (s.pkt);
}

int
pcap_datalink(pcap_t *p)
{
    return (p->linktype);
}

int
pcap_snapshot(pcap_t *p)
{
    return (p->snapshot);
}

int
pcap_is_swapped(pcap_t *p)
{
    return (p->rf.swapped);
}

int
pcap_major_version(pcap_t *p)
{
    return (p->rf.version_major);
}

int
pcap_minor_version(pcap_t *p)
{
    return (p->rf.version_minor);
}

FILE *
pcap_file(pcap_t *p)
{
    return (p->rf.rfile);
}

int
pcap_fileno(pcap_t *p)
{
    return (p->fd);
}

void
pcap_perror(pcap_t *p, char *prefix)
{
    fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
}

char *
pcap_geterr(pcap_t *p)
{
    return (p->errbuf);
}

/*
 * Not all systems have strerror().
 */
char *
pcap_strerror(int errnum)
{
    extern int sys_nerr;
    extern char *sys_errlist[];
    static char ebuf[20];

    if ((unsigned int)errnum < sys_nerr)
        return (sys_errlist[errnum]);
    (void)sprintf(ebuf, "Unknown error: %d", errnum);
    return(ebuf);
}

int    pcap_setfilter(pcap_t *p, struct bpf_program *bp)
{
    if (p->rf.rfile != NULL)
        return (pcap_setfilter_offline(p, bp));
    else
        return (pcap_setfilter_live(p, bp));
}

int pcap_stats(pcap_t *p, struct pcap_stat *ps)
{
    if (p->rf.rfile != NULL)
        return (pcap_stats_offline(p, ps));
    else
        return (pcap_stats_live(p, ps));
}

void
pcap_close(pcap_t *p)
{
    /*XXX*/
    if (p->fd >= 0)
        close(p->fd);
    if (p->rf.rfile != NULL) {
        fclose(p->rf.rfile);
        if (p->rf.base != NULL)
            free(p->rf.base);
    } else if (p->buffer != NULL)
        free(p->buffer);

    free(p);
}