/* netxray.c
 *
 * $Id: netxray.c,v 1.21 2000/01/13 07:09:18 guy Exp $
 *
 * Wiretap Library
 * Copyright (c) 1998 by Gilbert Ramirez <gram@verdict.uthscsa.edu>
 * 
 * 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 <stdlib.h>
#include <errno.h>
#include <time.h>
#include <string.h>
#include "wtap.h"
#include "file_wrappers.h"
#include "netxray.h"
#include "buffer.h"

/* Capture file header, *including* magic number, is padded to 128 bytes. */
#define	CAPTUREFILE_HEADER_SIZE	128

/* Magic number in NetXRay files. */
static const char netxray_magic[] = {	/* magic header */
	'X', 'C', 'P', '\0'
};

/* NetXRay file header (minus magic number). */
struct netxray_hdr {
	char	version[8];	/* version number */
	guint32	start_time;	/* UNIX time when capture started */
	guint32	nframes;	/* number of packets */
	guint32	xxx;		/* unknown */
	guint32	start_offset;	/* offset of first packet in capture */
	guint32	end_offset;	/* offset after last packet in capture */
	guint32 xxy[3];		/* unknown */
	guint16	network;	/* datalink type */
	guint8	xxz[6];
	guint32	timelo;		/* lower 32 bits of time stamp of capture start */
	guint32	timehi;		/* upper 32 bits of time stamp of capture start */
	/*
	 * XXX - other stuff.
	 */
};

/* Version number strings. */
static const char vers_1_0[] = {
	'0', '0', '1', '.', '0', '0', '0', '\0'
};

static const char vers_1_1[] = {
	'0', '0', '1', '.', '1', '0', '0', '\0'
};

static const char vers_2_001[] = {
	'0', '0', '2', '.', '0', '0', '1', '\0'
};

/* NetXRay 1.x data record format - followed by frame data. */
struct netxrayrec_1_x_hdr {
	guint32	timelo;		/* lower 32 bits of time stamp */
	guint32	timehi;		/* upper 32 bits of time stamp */
	guint16	orig_len;	/* packet length */
	guint16	incl_len;	/* capture length */
	guint32	xxx[4];		/* unknown */
};

/* NetXRay 2.x data record format - followed by frame data. */
struct netxrayrec_2_x_hdr {
	guint32	timelo;		/* lower 32 bits of time stamp */
	guint32	timehi;		/* upper 32 bits of time stamp */
	guint16	orig_len;	/* packet length */
	guint16	incl_len;	/* capture length */
	guint32	xxx[7];		/* unknown */
};

static int netxray_read(wtap *wth, int *err);
static gboolean netxray_dump_1_1(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
	const u_char *pd, int *err);
static gboolean netxray_dump_close_1_1(wtap_dumper *wdh, int *err);

int netxray_open(wtap *wth, int *err)
{
	int bytes_read;
	char magic[sizeof netxray_magic];
	struct netxray_hdr hdr;
	double timeunit;
	int version_major;
	int file_type;
	double t;
	static const int netxray_encap[] = {
		WTAP_ENCAP_ETHERNET,
		WTAP_ENCAP_TR,
		WTAP_ENCAP_FDDI_BITSWAPPED,
		WTAP_ENCAP_UNKNOWN,	/* WAN */
		WTAP_ENCAP_UNKNOWN,	/* LocalTalk */
		WTAP_ENCAP_UNKNOWN,	/* "DIX" - should not occur */
		WTAP_ENCAP_UNKNOWN,	/* ARCNET raw */
		WTAP_ENCAP_UNKNOWN,	/* ARCNET 878.2 */
		WTAP_ENCAP_UNKNOWN,	/* ATM */
		WTAP_ENCAP_UNKNOWN,	/* Wireless WAN */
		WTAP_ENCAP_UNKNOWN	/* IrDA */
	};
	#define NUM_NETXRAY_ENCAPS (sizeof netxray_encap / sizeof netxray_encap[0])

	/* Read in the string that should be at the start of a NetXRay
	 * file */
	file_seek(wth->fh, 0, SEEK_SET);
	wth->data_offset = 0;
	errno = WTAP_ERR_CANT_READ;
	bytes_read = file_read(magic, 1, sizeof magic, wth->fh);
	if (bytes_read != sizeof magic) {
		*err = file_error(wth->fh);
		if (*err != 0)
			return -1;
		return 0;
	}
	wth->data_offset += sizeof magic;

	if (memcmp(magic, netxray_magic, sizeof netxray_magic) != 0) {
		return 0;
	}

	/* Read the rest of the header. */
	errno = WTAP_ERR_CANT_READ;
	bytes_read = file_read(&hdr, 1, sizeof hdr, wth->fh);
	if (bytes_read != sizeof hdr) {
		*err = file_error(wth->fh);
		if (*err != 0)
			return -1;
		return 0;
	}
	wth->data_offset += sizeof hdr;

	/* It appears that version 1.1 files (as produced by Windows
	 * Sniffer Pro 2.0.01) have the time stamp in microseconds,
	 * rather than the milliseconds version 1.0 files appear to have.
	 *
	 * It also appears that version 2.001 files (as produced by
	 * Windows(?) Sniffer Pro 2.50.05) have per-packet headers with
	 * some extra fields. */
	if (memcmp(hdr.version, vers_1_0, sizeof vers_1_0) == 0) {
		timeunit = 1000.0;
		version_major = 1;
		file_type = WTAP_FILE_NETXRAY_1_0;
	} else if (memcmp(hdr.version, vers_1_1, sizeof vers_1_1) == 0) {
		timeunit = 1000000.0;
		version_major = 1;
		file_type = WTAP_FILE_NETXRAY_1_1;
	} else if (memcmp(hdr.version, vers_2_001, sizeof vers_2_001) == 0) {
		timeunit = 1000000.0;
		version_major = 2;
		file_type = WTAP_FILE_NETXRAY_2_001;
	} else {
		g_message("netxray: version \"%.8s\" unsupported", hdr.version);
		*err = WTAP_ERR_UNSUPPORTED;
		return -1;
	}

	hdr.network = pletohs(&hdr.network);
	if (hdr.network >= NUM_NETXRAY_ENCAPS
	    || netxray_encap[hdr.network] == WTAP_ENCAP_UNKNOWN) {
		g_message("netxray: network type %u unknown or unsupported",
		    hdr.network);
		*err = WTAP_ERR_UNSUPPORTED;
		return -1;
	}

	/* This is a netxray file */
	wth->file_type = file_type;
	wth->capture.netxray = g_malloc(sizeof(netxray_t));
	wth->subtype_read = netxray_read;
	wth->file_encap = netxray_encap[hdr.network];
	wth->snapshot_length = 16384;	/* XXX - not available in header */
	wth->capture.netxray->start_time = pletohl(&hdr.start_time);
	wth->capture.netxray->timeunit = timeunit;
	t = (double)pletohl(&hdr.timelo)
	    + (double)pletohl(&hdr.timehi)*4294967296.0;
	t = t/timeunit;
	wth->capture.netxray->start_timestamp = t;
	wth->capture.netxray->version_major = version_major;
	/*wth->frame_number = 0;*/
	/*wth->file_byte_offset = 0x10b;*/

	/* Remember the offset after the last packet in the capture (which
	 * isn't necessarily the last packet in the file), as it appears
	 * there's sometimes crud after it. */
	wth->capture.netxray->wrapped = 0;
	wth->capture.netxray->end_offset = pletohl(&hdr.end_offset);

	/* Seek to the beginning of the data records. */
	file_seek(wth->fh, pletohl(&hdr.start_offset), SEEK_SET);
	wth->data_offset = pletohl(&hdr.start_offset);

	return 1;
}

/* Read the next packet */
static int netxray_read(wtap *wth, int *err)
{
	guint32	packet_size;
	int	bytes_read;
	union {
		struct netxrayrec_1_x_hdr hdr_1_x;
		struct netxrayrec_2_x_hdr hdr_2_x;
	}	hdr;
	int	hdr_size = 0;
	int	data_offset;
	double	t;

reread:
	/* Have we reached the end of the packet data? */
	if (wth->data_offset == wth->capture.netxray->end_offset) {
		/* Yes. */
		return 0;
	}
	/* Read record header. */
	switch (wth->capture.netxray->version_major) {

	case 1:
		hdr_size = sizeof (struct netxrayrec_1_x_hdr);
		break;

	case 2:
		hdr_size = sizeof (struct netxrayrec_2_x_hdr);
		break;
	}
	errno = WTAP_ERR_CANT_READ;
	bytes_read = file_read(&hdr, 1, hdr_size, wth->fh);
	if (bytes_read != hdr_size) {
		*err = file_error(wth->fh);
		if (*err != 0)
			return -1;
		if (bytes_read != 0) {
			*err = WTAP_ERR_SHORT_READ;
			return -1;
		}

		/* We're at EOF.  Wrap? */
		if (!wth->capture.netxray->wrapped) {
			/* Yes.  Remember that we did. */
			wth->capture.netxray->wrapped = 1;
			file_seek(wth->fh, CAPTUREFILE_HEADER_SIZE, SEEK_SET);
			wth->data_offset = CAPTUREFILE_HEADER_SIZE;
			goto reread;
		}

		/* We've already wrapped - don't wrap again. */
		return 0;
	}
	wth->data_offset += hdr_size;

	packet_size = pletohs(&hdr.hdr_1_x.incl_len);
	buffer_assure_space(wth->frame_buffer, packet_size);
	data_offset = wth->data_offset;
	errno = WTAP_ERR_CANT_READ;
	bytes_read = file_read(buffer_start_ptr(wth->frame_buffer), 1,
			packet_size, wth->fh);

	if (bytes_read != packet_size) {
		*err = file_error(wth->fh);
		if (*err == 0)
			*err = WTAP_ERR_SHORT_READ;
		return -1;
	}
	wth->data_offset += packet_size;

	t = (double)pletohl(&hdr.hdr_1_x.timelo)
	    + (double)pletohl(&hdr.hdr_1_x.timehi)*4294967296.0;
	t /= wth->capture.netxray->timeunit;
	t -= wth->capture.netxray->start_timestamp;
	wth->phdr.ts.tv_sec = wth->capture.netxray->start_time + (long)t;
	wth->phdr.ts.tv_usec = (unsigned long)((t-(double)(unsigned long)(t))
		*1.0e6);
	wth->phdr.caplen = packet_size;
	wth->phdr.len = pletohs(&hdr.hdr_1_x.orig_len);
	wth->phdr.pkt_encap = wth->file_encap;

	return data_offset;
}

static const int wtap_encap[] = {
    -1,		/* WTAP_ENCAP_UNKNOWN -> unsupported */
    0,		/* WTAP_ENCAP_ETHERNET -> NDIS Ethernet */
    1,		/* WTAP_ENCAP_TR -> NDIS Token Ring */
    -1,		/* WTAP_ENCAP_SLIP -> unsupported */
    -1,		/* WTAP_ENCAP_PPP -> unsupported */
    2,		/* WTAP_ENCAP_FDDI -> NDIS FDDI */
    2,		/* WTAP_ENCAP_FDDI_BITSWAPPED -> NDIS FDDI */
    -1,		/* WTAP_ENCAP_RAW_IP -> unsupported */
    -1,		/* WTAP_ENCAP_ARCNET -> unsupported */
    -1,		/* WTAP_ENCAP_ATM_RFC1483 -> unsupported */
    -1,		/* WTAP_ENCAP_LINUX_ATM_CLIP -> unsupported */
    -1,		/* WTAP_ENCAP_LAPB -> unsupported */
    -1,		/* WTAP_ENCAP_ATM_SNIFFER -> unsupported */
    -1		/* WTAP_ENCAP_NULL -> unsupported */
};
#define NUM_WTAP_ENCAPS (sizeof wtap_encap / sizeof wtap_encap[0])

/* Returns 0 if we could write the specified encapsulation type,
   an error indication otherwise. */
int netxray_dump_can_write_encap(int filetype, int encap)
{
    /* Per-packet encapsulations aren't supported. */
    if (encap == WTAP_ENCAP_PER_PACKET)
	return WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED;

    if (encap < 0 || encap >= NUM_WTAP_ENCAPS || wtap_encap[encap] == -1)
	return WTAP_ERR_UNSUPPORTED_ENCAP;

    return 0;
}

/* Returns TRUE on success, FALSE on failure; sets "*err" to an error code on
   failure */
gboolean netxray_dump_open_1_1(wtap_dumper *wdh, int *err)
{
    /* This is a netxray file */
    wdh->subtype_write = netxray_dump_1_1;
    wdh->subtype_close = netxray_dump_close_1_1;

    /* We can't fill in all the fields in the file header, as we
       haven't yet written any packets.  As we'll have to rewrite
       the header when we've written out all the packets, we just
       skip over the header for now. */
    fseek(wdh->fh, CAPTUREFILE_HEADER_SIZE, SEEK_SET);

    wdh->private.netxray = g_malloc(sizeof(netxray_dump_t));
    wdh->private.netxray->first_frame = TRUE;
    wdh->private.netxray->start.tv_sec = 0;
    wdh->private.netxray->start.tv_usec = 0;
    wdh->private.netxray->nframes = 0;

    return TRUE;
}

/* Write a record for a packet to a dump file.
   Returns TRUE on success, FALSE on failure. */
static gboolean netxray_dump_1_1(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
    const u_char *pd, int *err)
{
    netxray_dump_t *priv = wdh->private.netxray;
    guint32 timestamp;
    struct netxrayrec_1_x_hdr rec_hdr;
    int nwritten;

    /* NetXRay/Windows Sniffer files have a capture start date/time
       in the header, in a UNIX-style format, with one-second resolution,
       and a start time stamp with microsecond resolution that's just
       an arbitrary time stamp relative to some unknown time (boot
       time?), and have times relative to the start time stamp in
       the packet headers; pick the seconds value of the time stamp
       of the first packet as the UNIX-style start date/time, and make
       the high-resolution start time stamp 0, with the time stamp of
       packets being the delta between the stamp of the packet and
       the stamp of the first packet with the microseconds part 0. */
    if (priv->first_frame) {
	priv->first_frame = FALSE;
	priv->start = phdr->ts;
    }

    /* build the header for each packet */
    memset(&rec_hdr, '\0', sizeof(rec_hdr));
    timestamp = (phdr->ts.tv_sec - priv->start.tv_sec)*1000000 +
        phdr->ts.tv_usec;
    rec_hdr.timelo = htolel(timestamp);
    rec_hdr.timehi = htolel(0);
    rec_hdr.orig_len = htoles(phdr->len);
    rec_hdr.incl_len = htoles(phdr->caplen);
	
    nwritten = fwrite(&rec_hdr, 1, sizeof(rec_hdr), wdh->fh);
    if (nwritten != sizeof(rec_hdr)) {
	if (nwritten < 0)
	    *err = errno;
	else
	    *err = WTAP_ERR_SHORT_WRITE;
	return FALSE;
    }

    /* write the packet data */	
    nwritten = fwrite(pd, 1, phdr->caplen, wdh->fh);
    if (nwritten != phdr->caplen) {
	if (nwritten < 0)
	    *err = errno;
	else
	    *err = WTAP_ERR_SHORT_WRITE;
	return FALSE;
    }
	
    priv->nframes++;

    return TRUE;
}

/* Finish writing to a dump file.
   Returns TRUE on success, FALSE on failure. */
static gboolean netxray_dump_close_1_1(wtap_dumper *wdh, int *err)
{
    char hdr_buf[CAPTUREFILE_HEADER_SIZE - sizeof(netxray_magic)];
    netxray_dump_t *priv = wdh->private.netxray;
    guint32 filelen;
    struct netxray_hdr file_hdr;
    int nwritten;

    filelen = ftell(wdh->fh);

    /* Go back to beginning */
    fseek(wdh->fh, 0, SEEK_SET);

    /* Rewrite the file header. */
    nwritten = fwrite(netxray_magic, 1, sizeof netxray_magic, wdh->fh);
    if (nwritten != sizeof netxray_magic) {
	if (nwritten < 0)
	    *err = errno;
	else
	    *err = WTAP_ERR_SHORT_WRITE;
	return FALSE;
    }

    /* "sniffer" version ? */
    memset(&file_hdr, '\0', sizeof file_hdr);
    memcpy(file_hdr.version, vers_1_1, sizeof vers_1_1);
    file_hdr.start_time = htolel(priv->start.tv_sec);
    file_hdr.nframes = htolel(priv->nframes);
    file_hdr.start_offset = htolel(CAPTUREFILE_HEADER_SIZE);
    file_hdr.end_offset = htolel(filelen);
    file_hdr.network = htoles(wtap_encap[wdh->encap]);
    file_hdr.timelo = htolel(0);
    file_hdr.timehi = htolel(0);

    memset(hdr_buf, '\0', sizeof hdr_buf);
    memcpy(hdr_buf, &file_hdr, sizeof(file_hdr));
    nwritten = fwrite(hdr_buf, 1, sizeof hdr_buf, wdh->fh);
    if (nwritten != sizeof hdr_buf) {
	if (nwritten < 0)
	    *err = errno;
	else
	    *err = WTAP_ERR_SHORT_WRITE;
	return FALSE;
    }
	
    return TRUE;
}