/* packet-dcerpc-ndr.c
 * Routines for DCERPC NDR dissection
 * Copyright 2001, Todd Sabin <tas@webspan.net>
 *
 * $Id: packet-dcerpc-ndr.c 13198 2005-01-29 20:39:14Z guy $
 *
 * Ethereal - Network traffic analyzer
 * By Gerald Combs <gerald@ethereal.com>
 * Copyright 1998 Gerald Combs
 *
 * 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 <string.h>
#include <ctype.h>

#include <glib.h>
#include <epan/packet.h>
#include "packet-dcerpc.h"


/*
 * The NDR routines are for use by dcerpc subdissetors.  They're
 * primarily for making sure things are aligned properly according
 * to the rules of NDR.
 */

int
dissect_ndr_uint8 (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                   proto_tree *tree, guint8 *drep,
                   int hfindex, guint8 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    /* no alignment needed */
    return dissect_dcerpc_uint8 (tvb, offset, pinfo,
                                 tree, drep, hfindex, pdata);
}

int
dissect_ndr_uint16 (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, guint16 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }


    if (offset % 2) {
        offset++;
    }
    return dissect_dcerpc_uint16 (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

int
dissect_ndr_uint32 (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, guint32 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }


    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    return dissect_dcerpc_uint32 (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

/* Double uint32
   This function dissects the 64bit datatype that is common for
   ms interfaces and which is 32bit aligned.
   It is really just 2 uint32's
*/
int
dissect_ndr_duint32 (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, guint64 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    return dissect_dcerpc_uint64 (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

/* uint64 : hyper
   a 64 bit integer  aligned to proper 8 byte boundaries
*/
int
dissect_ndr_uint64 (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, guint64 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    if (offset % 8) {
        offset += 8 - (offset % 8);
    }
    return dissect_dcerpc_uint64 (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

int
dissect_ndr_float(tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep, 
                    int hfindex, gfloat *pdata)
{
    dcerpc_info *di;


    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    return dissect_dcerpc_float(tvb, offset, pinfo, 
                                  tree, drep, hfindex, pdata);
}


int
dissect_ndr_double(tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep, 
                    int hfindex, gdouble *pdata)
{
    dcerpc_info *di;


    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    if (offset % 8) {
        offset += 8 - (offset % 8);
    }
    return dissect_dcerpc_double(tvb, offset, pinfo, 
                                  tree, drep, hfindex, pdata);
}

/* handles unix 32 bit time_t */
int
dissect_ndr_time_t (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, guint32 *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }


    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    return dissect_dcerpc_time_t (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

int
dissect_ndr_uuid_t (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                    proto_tree *tree, guint8 *drep,
                    int hfindex, e_uuid_t *pdata)
{
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    /* uuid's are aligned to 4 bytes, due to initial uint32 in struct */
    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    return dissect_dcerpc_uuid_t (tvb, offset, pinfo,
                                  tree, drep, hfindex, pdata);
}

/*
 * XXX - at least according to the DCE RPC 1.1 "nbase.idl", an
 * "ndr_context_handle" is an unsigned32 "context_handle_attributes"
 * and a uuid_t "context_handle_uuid".  The attributes do not appear to
 * be used, and always appear to be set to 0, in the DCE RPC 1.1 code.
 *
 * Should we display an "ndr_context_handle" with a tree holding the
 * attributes and the uuid_t?
 */
int
dissect_ndr_ctx_hnd (tvbuff_t *tvb, gint offset, packet_info *pinfo,
                     proto_tree *tree, guint8 *drep,
                     int hfindex, e_ctx_hnd *pdata)
{
    static e_ctx_hnd ctx_hnd;
    dcerpc_info *di;

    di=pinfo->private_data;
    if(di->conformant_run){
      /* just a run to handle conformant arrays, no scalars to dissect */
      return offset;
    }

    if (offset % 4) {
        offset += 4 - (offset % 4);
    }
    ctx_hnd.attributes = dcerpc_tvb_get_ntohl (tvb, offset, drep);
    dcerpc_tvb_get_uuid (tvb, offset+4, drep, &ctx_hnd.uuid);
    if (tree) {
        /* Bytes is bytes - don't worry about the data representation */
        proto_tree_add_item (tree, hfindex, tvb, offset, 20, FALSE);
    }
    if (pdata) {
        *pdata = ctx_hnd;
    }
    return offset + 20;
}
