source: rtems-libbsd/freebsd/contrib/libpcap/savefile.c @ 3d1e767

#include <machine/rtems-bsd-user-space.h>

/*
 * Copyright (c) 1993, 1994, 1995, 1996, 1997
 *      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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University 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 WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * savefile.c - supports offline use of tcpdump
 *      Extraction/creation by Jeffrey Mogul, DECWRL
 *      Modified by Steve McCanne, LBL.
 *
 * Used to save the received packet headers, after filtering, to
 * a file, and then read them later.
 * The first record in the file contains saved values for the machine
 * dependent values so we can print the dump file on any architecture.
 */

#ifndef lint
static const char rcsid[] _U_ =
    "@(#) $Header: /tcpdump/master/libpcap/savefile.c,v 1.183 2008-12-23 20:13:29 guy Exp $ (LBL)";
#endif

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef WIN32
#include <pcap-stdinc.h>
#else /* WIN32 */
#if HAVE_INTTYPES_H
#include <inttypes.h>
#elif HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_SYS_BITYPES_H
#include <sys/bitypes.h>
#endif
#include <sys/types.h>
#endif /* WIN32 */

#include <errno.h>
#include <memory.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "pcap-int.h"
#include "pcap/usb.h"

#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif

#include "sf-pcap.h"
#include "sf-pcap-ng.h"

/*
 * Setting O_BINARY on DOS/Windows is a bit tricky
 */
#if defined(WIN32)
  #define SET_BINMODE(f)  _setmode(_fileno(f), _O_BINARY)
#elif defined(MSDOS)
  #if defined(__HIGHC__)
  #define SET_BINMODE(f)  setmode(f, O_BINARY)
  #else
  #define SET_BINMODE(f)  setmode(fileno(f), O_BINARY)
  #endif
#endif

static int
sf_getnonblock(pcap_t *p, char *errbuf)
{
        /*
         * This is a savefile, not a live capture file, so never say
         * it's in non-blocking mode.
         */
        return (0);
}

static int
sf_setnonblock(pcap_t *p, int nonblock, char *errbuf)
{
        /*
         * This is a savefile, not a live capture file, so reject
         * requests to put it in non-blocking mode.  (If it's a
         * pipe, it could be put in non-blocking mode, but that
         * would significantly complicate the code to read packets,
         * as it would have to handle reading partial packets and
         * keeping the state of the read.)
         */
        snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
            "Savefiles cannot be put into non-blocking mode");
        return (-1);
}

static int
sf_stats(pcap_t *p, struct pcap_stat *ps)
{
        snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
            "Statistics aren't available from savefiles");
        return (-1);
}

#ifdef WIN32
static int
sf_setbuff(pcap_t *p, int dim)
{
        snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
            "The kernel buffer size cannot be set while reading from a file");
        return (-1);
}

static int
sf_setmode(pcap_t *p, int mode)
{
        snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
            "impossible to set mode while reading from a file");
        return (-1);
}

static int
sf_setmintocopy(pcap_t *p, int size)
{
        snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
            "The mintocopy parameter cannot be set while reading from a file");
        return (-1);
}
#endif

static int
sf_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
{
        strlcpy(p->errbuf, "Sending packets isn't supported on savefiles",
            PCAP_ERRBUF_SIZE);
        return (-1);
}

/*
 * Set direction flag: Which packets do we accept on a forwarding
 * single device? IN, OUT or both?
 */
static int
sf_setdirection(pcap_t *p, pcap_direction_t d)
{
        snprintf(p->errbuf, sizeof(p->errbuf),
            "Setting direction is not supported on savefiles");
        return (-1);
}

static void
sf_cleanup(pcap_t *p)
{
        if (p->sf.rfile != stdin)
                (void)fclose(p->sf.rfile);
        if (p->buffer != NULL)
                free(p->buffer);
        pcap_freecode(&p->fcode);
}

pcap_t *
pcap_open_offline(const char *fname, char *errbuf)
{
        FILE *fp;
        pcap_t *p;

        if (fname[0] == '-' && fname[1] == '\0')
        {
                fp = stdin;
#if defined(WIN32) || defined(MSDOS)
                /*
                 * We're reading from the standard input, so put it in binary
                 * mode, as savefiles are binary files.
                 */
                SET_BINMODE(fp);
#endif
        }
        else {
#if !defined(WIN32) && !defined(MSDOS)
                fp = fopen(fname, "r");
#else
                fp = fopen(fname, "rb");
#endif
                if (fp == NULL) {
                        snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname,
                            pcap_strerror(errno));
                        return (NULL);
                }
        }
        p = pcap_fopen_offline(fp, errbuf);
        if (p == NULL) {
                if (fp != stdin)
                        fclose(fp);
        }
        return (p);
}

#ifdef WIN32
pcap_t* pcap_hopen_offline(intptr_t osfd, char *errbuf)
{
        int fd;
        FILE *file;

        fd = _open_osfhandle(osfd, _O_RDONLY);
        if ( fd < 0 ) 
        {
                snprintf(errbuf, PCAP_ERRBUF_SIZE, pcap_strerror(errno));
                return NULL;
        }

        file = _fdopen(fd, "rb");
        if ( file == NULL ) 
        {
                snprintf(errbuf, PCAP_ERRBUF_SIZE, pcap_strerror(errno));
                return NULL;
        }

        return pcap_fopen_offline(file, errbuf);
}
#endif

static int (*check_headers[])(pcap_t *, bpf_u_int32, FILE *, char *) = {
        pcap_check_header,
        pcap_ng_check_header
};

#define N_FILE_TYPES    (sizeof check_headers / sizeof check_headers[0])

#ifdef WIN32
static
#endif
pcap_t *
pcap_fopen_offline(FILE *fp, char *errbuf)
{
        register pcap_t *p;
        bpf_u_int32 magic;
        size_t amt_read;
        u_int i;

        p = pcap_create_common("(savefile)", errbuf);
        if (p == NULL)
                return (NULL);

        /*
         * Read the first 4 bytes of the file; the network analyzer dump
         * file formats we support (pcap and pcap-ng), and several other
         * formats we might support in the future (such as snoop, DOS and
         * Windows Sniffer, and Microsoft Network Monitor) all have magic
         * numbers that are unique in their first 4 bytes.
         */
        amt_read = fread((char *)&magic, 1, sizeof(magic), fp);
        if (amt_read != sizeof(magic)) {
                if (ferror(fp)) {
                        snprintf(errbuf, PCAP_ERRBUF_SIZE,
                            "error reading dump file: %s",
                            pcap_strerror(errno));
                } else {
                        snprintf(errbuf, PCAP_ERRBUF_SIZE,
                            "truncated dump file; tried to read %lu file header bytes, only got %lu",
                            (unsigned long)sizeof(magic),
                            (unsigned long)amt_read);
                }
                goto bad;
        }

        /*
         * Try all file types.
         */
        for (i = 0; i < N_FILE_TYPES; i++) {
                switch ((*check_headers[i])(p, magic, fp, errbuf)) {

                case -1:
                        /*
                         * Error trying to read the header.
                         */
                        goto bad;

                case 1:
                        /*
                         * Yup, that's it.
                         */
                        goto found;
                }
        }

        /*
         * Well, who knows what this mess is....
         */
        snprintf(errbuf, PCAP_ERRBUF_SIZE, "unknown file format");
        goto bad;

found:
        p->sf.rfile = fp;

#ifdef PCAP_FDDIPAD
        /* Padding only needed for live capture fcode */
        p->fddipad = 0;
#endif

#if !defined(WIN32) && !defined(MSDOS)
        /*
         * You can do "select()" and "poll()" on plain files on most
         * platforms, and should be able to do so on pipes.
         *
         * You can't do "select()" on anything other than sockets in
         * Windows, so, on Win32 systems, we don't have "selectable_fd".
         */
        p->selectable_fd = fileno(fp);
#endif

        p->read_op = pcap_offline_read;
        p->inject_op = sf_inject;
        p->setfilter_op = install_bpf_program;
        p->setdirection_op = sf_setdirection;
        p->set_datalink_op = NULL;      /* we don't support munging link-layer headers */
        p->getnonblock_op = sf_getnonblock;
        p->setnonblock_op = sf_setnonblock;
        p->stats_op = sf_stats;
#ifdef WIN32
        p->setbuff_op = sf_setbuff;
        p->setmode_op = sf_setmode;
        p->setmintocopy_op = sf_setmintocopy;
#endif
        p->cleanup_op = sf_cleanup;
        p->activated = 1;

        return (p);
 bad:
        free(p);
        return (NULL);
}

/*
 * Read packets from a capture file, and call the callback for each
 * packet.
 * If cnt > 0, return after 'cnt' packets, otherwise continue until eof.
 */
int
pcap_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
        struct bpf_insn *fcode;
        int status = 0;
        int n = 0;
        u_char *data;

        while (status == 0) {
                struct pcap_pkthdr h;

                /*
                 * Has "pcap_breakloop()" been called?
                 * If so, return immediately - if we haven't read any
                 * packets, clear the flag and return -2 to indicate
                 * that we were told to break out of the loop, otherwise
                 * leave the flag set, so that the *next* call will break
                 * out of the loop without having read any packets, and
                 * return the number of packets we've processed so far.
                 */
                if (p->break_loop) {
                        if (n == 0) {
                                p->break_loop = 0;
                                return (-2);
                        } else
                                return (n);
                }

                status = p->sf.next_packet_op(p, &h, &data);
                if (status) {
                        if (status == 1)
                                return (0);
                        return (status);
                }

                if ((fcode = p->fcode.bf_insns) == NULL ||
                    bpf_filter(fcode, data, h.len, h.caplen)) {
                        (*callback)(user, &h, data);
                        if (++n >= cnt && cnt > 0)
                                break;
                }
        }
        /*XXX this breaks semantics tcpslice expects */
        return (n);
}