/* file.c
 *
 * $Id: file.c,v 1.66 2001/03/10 06:33:57 guy Exp $
 *
 * Wiretap Library
 * Copyright (c) 1998 by Gilbert Ramirez <gram@xiexie.org>
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

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

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif

#include <errno.h>

#ifdef HAVE_IO_H
#include <io.h>	/* open/close on win32 */
#endif

#include "wtap-int.h"
#include "file_wrappers.h"
#include "buffer.h"
#include "lanalyzer.h"
#include "ngsniffer.h"
#include "radcom.h"
#include "ascend.h"
#include "nettl.h"
#include "libpcap.h"
#include "snoop.h"
#include "iptrace.h"
#include "netmon.h"
#include "netxray.h"
#include "toshiba.h"
#include "i4btrace.h"
#include "csids.h"
#include "pppdump.h"
#include "etherpeek.h"

/* The open_file_* routines should return:
 *
 *	-1 on an I/O error;
 *
 *	1 if the file they're reading is one of the types it handles;
 *
 *	0 if the file they're reading isn't the type they're checking for.
 *
 * If the routine handles this type of file, it should set the "file_type"
 * field in the "struct wtap" to the type of the file.
 *
 * XXX - I need to drag my damn ANSI C spec in to figure out how to
 * declare a "const" array of pointers to functions; putting "const"
 * right after "static" isn't the right answer, at least according
 * to GCC, which whines if I do that.
 *
 * Put the trace files that are merely saved telnet-sessions last, since it's
 * possible that you could have captured someone a router telnet-session
 * using another tool. So, a libpcap trace of an toshiba "snoop" session
 * should be discovered as a libpcap file, not a toshiba file.
 */

static int (*open_routines[])(wtap *, int *) = {
	/* Files that have magic bytes in fixed locations. These
	 * are easy to identify.
	 */
	libpcap_open,
	lanalyzer_open,
	ngsniffer_open,
	snoop_open,
	iptrace_open,
	netmon_open,
	netxray_open,
	radcom_open,
	nettl_open,
	pppdump_open,
	etherpeek_open,

	/* Files whose magic headers are in text *somewhere* in the
	 * file (usually because the trace is just a saved copy of
	 * the telnet session). 
	 */
	ascend_open,
	toshiba_open,
	i4btrace_open,
	csids_open,
};

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

int wtap_def_seek_read(wtap *wth, int seek_off,
	union wtap_pseudo_header *pseudo_header, guint8 *pd, int len)
{
	file_seek(wth->random_fh, seek_off, SEEK_SET);

	return file_read(pd, sizeof(guint8), len, wth->random_fh);
}

/*
 * Visual C++ on Win32 systems doesn't define these.  (Old UNIX systems don't
 * define them either.)
 *
 * Visual C++ on Win32 systems doesn't define S_IFIFO, it defines _S_IFIFO.
 */
#ifndef S_ISREG
#define S_ISREG(mode)   (((mode) & S_IFMT) == S_IFREG)
#endif
#ifndef S_IFIFO
#define S_IFIFO	_S_IFIFO
#endif
#ifndef S_ISFIFO
#define S_ISFIFO(mode)  (((mode) & S_IFMT) == S_IFIFO)
#endif
#ifndef S_ISDIR
#define S_ISDIR(mode)   (((mode) & S_IFMT) == S_IFDIR)
#endif

/* Opens a file and prepares a wtap struct.
   If "do_random" is TRUE, it opens the file twice; the second open
   allows the application to do random-access I/O without moving
   the seek offset for sequential I/O, which is used by Ethereal
   so that it can do sequential I/O to a capture file that's being
   written to as new packets arrive independently of random I/O done
   to display protocol trees for packets when they're selected. */
wtap* wtap_open_offline(const char *filename, int *err, gboolean do_random)
{
	struct stat statb;
	wtap	*wth;
	int	i;

	/* First, make sure the file is valid */
	if (stat(filename, &statb) < 0) {
		*err = errno;
		return NULL;
	}
	if (! S_ISREG(statb.st_mode) && ! S_ISFIFO(statb.st_mode)) {
		if (S_ISDIR(statb.st_mode))
			*err = EISDIR;
		else
			*err = WTAP_ERR_NOT_REGULAR_FILE;
		return NULL;
	}

	errno = ENOMEM;
	wth = g_malloc(sizeof(wtap));
	if (wth == NULL) {
		*err = errno;
		return NULL;
	}

/* Win32 needs the O_BINARY flag for open() */
#ifndef O_BINARY
#define O_BINARY	0
#endif

	/* Open the file */
	errno = WTAP_ERR_CANT_OPEN;
	wth->fd = open(filename, O_RDONLY|O_BINARY);
	if (wth->fd < 0) {
		*err = errno;
		g_free(wth);
		return NULL;
	}
	if (!(wth->fh = filed_open(wth->fd, "rb"))) {
		*err = errno;
		g_free(wth);
		return NULL;
	}

	if (do_random) {
		if (!(wth->random_fh = file_open(filename, "rb"))) {
			*err = errno;
			file_close(wth->fh);
			g_free(wth);
			return NULL;
		}
	} else
		wth->random_fh = NULL;

	/* initialization */
	wth->file_encap = WTAP_ENCAP_UNKNOWN;
	wth->data_offset = 0;
	wth->subtype_sequential_close = NULL;
	wth->subtype_close = NULL;

	/* Try all file types */
	for (i = 0; i < N_FILE_TYPES; i++) {
		/* Seek back to the beginning of the file; the open routine
		   for the previous file type may have left the file
		   position somewhere other than the beginning, and the
		   open routine for this file type will probably want
		   to start reading at the beginning.

		   Initialize the data offset while we're at it. */
		file_seek(wth->fh, 0, SEEK_SET);
		wth->data_offset = 0;
		switch ((*open_routines[i])(wth, err)) {

		case -1:
			/* I/O error - give up */
			if (wth->random_fh != NULL)
				file_close(wth->random_fh);
			file_close(wth->fh);
			g_free(wth);
			return NULL;

		case 0:
			/* No I/O error, but not that type of file */
			break;

		case 1:
			/* We found the file type */
			goto success;
		}
	}

	/* Well, it's not one of the types of file we know about. */
	if (wth->random_fh != NULL)
		file_close(wth->random_fh);
	file_close(wth->fh);
	g_free(wth);
	*err = WTAP_ERR_FILE_UNKNOWN_FORMAT;
	return NULL;

success:
	wth->frame_buffer = g_malloc(sizeof(struct Buffer));
	buffer_init(wth->frame_buffer, 1500);
	return wth;
}

/* Table of the file types we know about. */
const static struct file_type_info {
	const char *name;
	const char *short_name;
	int	(*can_write_encap)(int, int);
	int	(*dump_open)(wtap_dumper *, int *);
} dump_open_table[WTAP_NUM_FILE_TYPES] = {
	/* WTAP_FILE_UNKNOWN */
	{ NULL, NULL,
	  NULL, NULL },

	/* WTAP_FILE_WTAP */
	{ "Wiretap (Ethereal)", NULL,
	  NULL, NULL },

	/* WTAP_FILE_PCAP */
	{ "libpcap (tcpdump, Ethereal, etc.)", "libpcap",
	  libpcap_dump_can_write_encap, libpcap_dump_open },

	/* WTAP_FILE_PCAP_SS990417 */
	{ "Red Hat Linux 6.1 libpcap (tcpdump)", "rh6_1libpcap",
	  libpcap_dump_can_write_encap, libpcap_dump_open },

	/* WTAP_FILE_PCAP_SS990915 */
	{ "SuSE Linux 6.3 libpcap (tcpdump)", "suse6_3libpcap",
	  libpcap_dump_can_write_encap, libpcap_dump_open },

	/* WTAP_FILE_PCAP_SS991029 */
	{ "modified libpcap (tcpdump)", "modlibpcap",
	  libpcap_dump_can_write_encap, libpcap_dump_open },

	/* WTAP_FILE_PCAP_NOKIA */
	{ "Nokia libpcap (tcpdump)", "nokialibpcap",
	  libpcap_dump_can_write_encap, libpcap_dump_open },

	/* WTAP_FILE_LANALYZER */
	{ "Novell LANalyzer", NULL,
	  NULL, NULL },

	/* WTAP_FILE_NGSNIFFER_UNCOMPRESSED */
	{ "Network Associates Sniffer (DOS-based)", "ngsniffer",
	  ngsniffer_dump_can_write_encap, ngsniffer_dump_open },

	/* WTAP_FILE_NGSNIFFER_COMPRESSED */
	{ "Network Associates Sniffer (DOS-based), compressed", "ngsniffer_comp",
	  NULL, NULL },

	/* WTAP_FILE_SNOOP */
	{ "Sun snoop", "snoop",
	  snoop_dump_can_write_encap, snoop_dump_open },

	/* WTAP_FILE_IPTRACE_1_0 */
	{ "AIX iptrace 1.0", NULL,
	  NULL, NULL },

	/* WTAP_FILE_IPTRACE_2_0 */
	{ "AIX iptrace 2.0", NULL,
	  NULL, NULL },

	/* WTAP_FILE_NETMON_1_x */
	{ "Microsoft Network Monitor 1.x", "netmon1",
	  netmon_dump_can_write_encap, netmon_dump_open },

	/* WTAP_FILE_NETMON_2_x */
	{ "Microsoft Network Monitor 2.x", "netmon2",
	  netmon_dump_can_write_encap, netmon_dump_open },

	/* WTAP_FILE_NETXRAY_1_0 */
	{ "Cinco Networks NetXRay", NULL,
	  NULL, NULL },

	/* WTAP_FILE_NETXRAY_1_1 */
	{ "Network Associates Sniffer (Windows-based) 1.1", "ngwsniffer_1_1",
	  netxray_dump_can_write_encap, netxray_dump_open_1_1 },

	/* WTAP_FILE_NETXRAY_2_00x */
	{ "Network Associates Sniffer (Windows-based) 2.00x", NULL,
	  NULL, NULL },

	/* WTAP_FILE_RADCOM */
	{ "RADCOM WAN/LAN analyzer", NULL,
	  NULL, NULL },

	/* WTAP_FILE_ASCEND */
	{ "Lucent/Ascend access server trace", NULL,
	  NULL, NULL },

	/* WTAP_FILE_NETTL */
	{ "HP-UX nettl trace", NULL,
	  NULL, NULL },

	/* WTAP_FILE_TOSHIBA */
	{ "Toshiba Compact ISDN Router snoop trace", NULL,
	  NULL, NULL },

	/* WTAP_FILE_I4BTRACE */
	{ "I4B ISDN trace", NULL,
	  NULL, NULL },

        /* WTAP_FILE_CSIDS */
        { "CSIDS IPLog", NULL,
          NULL, NULL },

        /* WTAP_FILE_PPPDUMP */
        { "pppd log (pppdump format)", NULL,
          NULL, NULL },

	/* WTAP_FILE_ETHERPEEK_MAC_V56 */
	{ "Etherpeek trace (Macintosh V5 & V6)", NULL,
	  NULL, NULL },

	/* WTAP_FILE_ETHERPEEK_MAC_V7 */
	{ "Etherpeek trace (Macintosh V7)", NULL,
	  NULL, NULL },
};

/* Name that should be somewhat descriptive. */
const char *wtap_file_type_string(int filetype)
{
	if (filetype < 0 || filetype >= WTAP_NUM_FILE_TYPES) {
		g_error("Unknown capture file type %d", filetype);
		return NULL;
	} else
		return dump_open_table[filetype].name;
}

/* Name to use in, say, a command-line flag specifying the type. */
const char *wtap_file_type_short_string(int filetype)
{
	if (filetype < 0 || filetype >= WTAP_NUM_FILE_TYPES)
		return NULL;
	else
		return dump_open_table[filetype].short_name;
}

/* Translate a short name to a capture file type. */
int wtap_short_string_to_file_type(const char *short_name)
{
	int filetype;

	for (filetype = 0; filetype < WTAP_NUM_FILE_TYPES; filetype++) {
		if (dump_open_table[filetype].short_name != NULL &&
		    strcmp(short_name, dump_open_table[filetype].short_name) == 0)
			return filetype;
	}
	return -1;	/* no such file type, or we can't write it */
}

gboolean wtap_dump_can_open(int filetype)
{
	if (filetype < 0 || filetype >= WTAP_NUM_FILE_TYPES
	    || dump_open_table[filetype].dump_open == NULL)
		return FALSE;

	return TRUE;
}

gboolean wtap_dump_can_write_encap(int filetype, int encap)
{
	if (filetype < 0 || filetype >= WTAP_NUM_FILE_TYPES
	    || dump_open_table[filetype].can_write_encap == NULL)
		return FALSE;

	if ((*dump_open_table[filetype].can_write_encap)(filetype, encap) != 0)
		return FALSE;

	return TRUE;
}

static wtap_dumper* wtap_dump_open_common(FILE *fh, int filetype,
    int encap, int snaplen, int *err);

wtap_dumper* wtap_dump_open(const char *filename, int filetype, int encap,
				int snaplen, int *err)
{
	FILE *fh;

	/* In case "fopen()" fails but doesn't set "errno", set "errno"
	   to a generic "the open failed" error. */
	errno = WTAP_ERR_CANT_OPEN;
	fh = fopen(filename, "wb");
	if (fh == NULL) {
		*err = errno;
		return NULL;	/* can't create file */
	}
	return wtap_dump_open_common(fh, filetype, encap, snaplen, err);
}

wtap_dumper* wtap_dump_fdopen(int fd, int filetype, int encap, int snaplen,
				int *err)
{
	FILE *fh;

	/* In case "fopen()" fails but doesn't set "errno", set "errno"
	   to a generic "the open failed" error. */
	errno = WTAP_ERR_CANT_OPEN;
	fh = fdopen(fd, "wb");
	if (fh == NULL) {
		*err = errno;
		return NULL;	/* can't create standard I/O stream */
	}
	return wtap_dump_open_common(fh, filetype, encap, snaplen, err);
}

static wtap_dumper* wtap_dump_open_common(FILE *fh, int filetype, int encap,
					int snaplen, int *err)
{
	wtap_dumper *wdh;

	if (filetype < 0 || filetype >= WTAP_NUM_FILE_TYPES
	    || dump_open_table[filetype].dump_open == NULL) {
		/* Invalid type, or type we don't know how to write. */
		*err = WTAP_ERR_UNSUPPORTED_FILE_TYPE;
		/* NOTE: this means the FD handed to "wtap_dump_fdopen()"
		   will be closed if we can't write that file type. */
		fclose(fh);
		return NULL;
	}

	/* OK, we know how to write that type; can we write the specified
	   encapsulation type? */
	*err = (*dump_open_table[filetype].can_write_encap)(filetype, encap);
	if (*err != 0) {
		/* NOTE: this means the FD handed to "wtap_dump_fdopen()"
		   will be closed if we can't write that encapsulation type. */
		fclose(fh);
		return NULL;
	}

	/* OK, we can write the specified encapsulation type.  Allocate
	   a data structure for the output stream. */
	wdh = g_malloc(sizeof (wtap_dumper));
	if (wdh == NULL) {
		*err = errno;
		/* NOTE: this means the FD handed to "wtap_dump_fdopen()"
		   will be closed if the malloc fails. */
		fclose(fh);
		return NULL;
	}
	wdh->fh = fh;
	wdh->file_type = filetype;
	wdh->snaplen = snaplen;
	wdh->encap = encap;
	wdh->dump.opaque = NULL;
	wdh->subtype_write = NULL;
	wdh->subtype_close = NULL;

	/* Now try to open the file for writing. */
	if (!(*dump_open_table[filetype].dump_open)(wdh, err)) {
		/* The attempt failed. */
		g_free(wdh);
		/* NOTE: this means the FD handed to "wtap_dump_fdopen()"
		   will be closed if the open fails. */
		fclose(fh);
		return NULL;
	}

	return wdh;	/* success! */
}

FILE* wtap_dump_file(wtap_dumper *wdh)
{
	return wdh->fh;
}

gboolean wtap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
    const union wtap_pseudo_header *pseudo_header, const u_char *pd, int *err)
{
	return (wdh->subtype_write)(wdh, phdr, pseudo_header, pd, err);
}

gboolean wtap_dump_close(wtap_dumper *wdh, int *err)
{
	gboolean ret = TRUE;

	if (wdh->subtype_close != NULL) {
		/* There's a close routine for this dump stream. */
		if (!(wdh->subtype_close)(wdh, err))
			ret = FALSE;
	}
	errno = WTAP_ERR_CANT_CLOSE;
	if (fclose(wdh->fh) == EOF) {
		if (ret) {
			/* The per-format close function succeeded,
			   but the fclose didn't.  Save the reason
			   why, if our caller asked for it. */
			if (err != NULL)
				*err = errno;
		}
		ret = FALSE;
	}
	if (wdh->dump.opaque != NULL)
		g_free(wdh->dump.opaque);
	g_free(wdh);
	return ret;
}