/* packet-lanforge.c
 * Routines for "LANforge traffic generator IP protocol" dissection
 * Copyright 2008
 * Ben Greear <greearb@candelatech.com>
 *
 * Based on pktgen dissectory by:
 * Francesco Fondelli <francesco dot fondelli, gmail dot com>
 *
 * $Id: packet-lanforge.c 29446 2009-08-16 12:36:22Z krj $
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * 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.
 */

/* LANforge generates network traffic for load & performance testing.
 * See http://www.candelatech.com for more info.
 */

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

#if 0
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#endif

#include <glib.h>

#include <epan/packet.h>

/* magic num used for heuristic */
static const guint8 lanforge_magic[] = { 0x1a, 0x2b, 0x3c, 0x4d };

/* Initialize the protocol and registered fields */
static int proto_lanforge = -1;

/* lanforge header */
static int hf_lanforge_crc = -1;
static int hf_lanforge_magic = -1;
static int hf_lanforge_src_session = -1;
static int hf_lanforge_dst_session = -1;
static int hf_lanforge_pld_len = -1;
static int hf_lanforge_pld_pattern = -1;
static int hf_lanforge_seq = -1;
static int hf_lanforge_tx_time_s = -1;
static int hf_lanforge_tx_time_ns = -1;
static int hf_lanforge_timestamp = -1;

/* Initialize the subtree pointer */
static gint ett_lanforge = -1;

/* data dissector handle */
static dissector_handle_t data_handle;

/* entry point */
static gboolean dissect_lanforge(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
    proto_item *ti = NULL;
    proto_item *tmp = NULL;
    proto_tree *lanforge_tree = NULL;
    guint32 offset = 0;
    nstime_t tstamp;
    guint32 tss;

    /* check for min size */
    if(tvb_length(tvb) < 28) { 	/* Not a LANforge packet. */
	return FALSE;
    }
    
    /* check for magic number */
    if(tvb_memeql(tvb, 4, lanforge_magic, 4) == -1) { /* Not a LANforge packet. */
       return FALSE;
    }
        
    /* Make entries in Protocol column and Info column on summary display */
    
    col_set_str(pinfo->cinfo, COL_PROTOCOL, "LANforge");
    
    if(check_col(pinfo->cinfo, COL_INFO)) {
	col_add_fstr(pinfo->cinfo, COL_INFO, "Seq: %u", tvb_get_ntohl(tvb, 16));
    }
    
    if(tree) {
	
	/* create display subtree for the protocol */
	
	ti = proto_tree_add_item(tree, proto_lanforge, tvb, 0, -1, FALSE);
	
	lanforge_tree = proto_item_add_subtree(ti, ett_lanforge);
	
	/* add items to the subtree */
	
	proto_tree_add_item(lanforge_tree, hf_lanforge_crc, tvb, offset, 4, FALSE);
	offset+=4;

        proto_tree_add_item(lanforge_tree, hf_lanforge_magic, tvb, offset, 4, FALSE);
	offset+=4;

	proto_tree_add_item(lanforge_tree, hf_lanforge_src_session, tvb, offset, 2, FALSE);
	offset+=2;
        
	proto_tree_add_item(lanforge_tree, hf_lanforge_dst_session, tvb, offset, 2, FALSE);
	offset+=2;

        proto_tree_add_item(lanforge_tree, hf_lanforge_pld_len, tvb, offset, 2, FALSE);
        offset+=2;

        proto_tree_add_item(lanforge_tree, hf_lanforge_pld_pattern, tvb, offset, 2, FALSE);
        offset+=2;

        proto_tree_add_item(lanforge_tree, hf_lanforge_seq, tvb, offset, 4, FALSE);
	offset+=4;

        tss = tvb_get_ntohl(tvb, offset);
	tstamp.secs = tss;
	tmp = proto_tree_add_item(lanforge_tree, hf_lanforge_tx_time_s, tvb, offset, 4, FALSE);
	PROTO_ITEM_SET_GENERATED(tmp);
	offset+=4;

        tss = tvb_get_ntohl(tvb, offset);
	tstamp.nsecs = tss;
	tmp = proto_tree_add_item(lanforge_tree, hf_lanforge_tx_time_ns, tvb, offset, 4, FALSE);
	PROTO_ITEM_SET_GENERATED(tmp);
	offset+=4;

	proto_tree_add_time(lanforge_tree, hf_lanforge_timestamp, tvb, offset - 8, 8, &tstamp);
	
#if 0
	if(tvb_length_remaining(tvb, offset)) /* random data */
	    proto_tree_add_text(lanforge_tree, tvb, offset, -1, "Data (%u bytes)",
				tvb_length_remaining(tvb, offset));
#else
	if(tvb_length_remaining(tvb, offset)) /* random data */
	    call_dissector(data_handle, tvb_new_subset_remaining(tvb, offset), pinfo,
		lanforge_tree);
#endif
    }

    return TRUE;
}


/* Register the protocol with Wireshark */
void proto_register_lanforge(void)
{                 
    /* Setup list of header fields */
    
    static hf_register_info hf[] = {
	
	{ &hf_lanforge_crc,
	  { 
	      "CRC", "LANforge.CRC", 
	      FT_UINT32, BASE_HEX, NULL, 0x0, 
	      "The LANforge CRC number", HFILL
	  }
	},

        { &hf_lanforge_magic,
	  { 
	      "Magic number", "LANforge.magic", 
	      FT_UINT32, BASE_HEX, NULL, 0x0, 
	      "The LANforge magic number", HFILL
	  }
	},

	{ &hf_lanforge_src_session,
	  { 
	      "Source session ID", "LANforge.source-session-id", 
	      FT_UINT16, BASE_DEC, NULL, 0x0, 
	      "The LANforge source session ID", HFILL
	  }
	},
        
	{ &hf_lanforge_dst_session,
	  { 
	      "Dest session ID", "LANforge.dest-session-id", 
	      FT_UINT16, BASE_DEC, NULL, 0x0, 
	      "The LANforge dest session ID", HFILL
	  }
	},
        
	{ &hf_lanforge_pld_len,
	  { 
	      "Payload Length", "LANforge.pld-length", 
	      FT_UINT16, BASE_DEC, NULL, 0x0, 
	      "The LANforge payload length", HFILL
	  }
	},

        { &hf_lanforge_pld_pattern,
	  { 
	      "Payload Pattern", "LANforge.pld-pattern", 
	      FT_UINT16, BASE_DEC, NULL, 0x0, 
	      "The LANforge payload pattern", HFILL
	  }
	},

	{ &hf_lanforge_seq,
	  { 
	      "Sequence Number", "LANforge.seqno", 
	      FT_UINT32, BASE_DEC, NULL, 0x0, 
	      "The LANforge Sequence Number", HFILL
	  }
	},

	{ &hf_lanforge_tx_time_s,
	  { 
	      "Timestamp Secs", "LANforge.ts-secs", 
	      FT_UINT32, BASE_DEC, NULL, 0x0, 
	      "Timestamp secs", HFILL
	  }
	},
        
	{ &hf_lanforge_tx_time_ns,
	  { 
	      "Timestamp nsecs", "LANforge.ts-nsecs", 
	      FT_UINT32, BASE_DEC, NULL, 0x0, 
	      NULL, HFILL
	  }
	},

	{ &hf_lanforge_timestamp,
	  { 
	      "Timestamp", "LANforge.timestamp", 
	      FT_ABSOLUTE_TIME, BASE_NONE, NULL, 0x0,
	      NULL, HFILL
	  }
	}
    };
	
    /* Setup protocol subtree array */
	
    static gint *ett[] = {
	&ett_lanforge
    };
	
    /* Register the protocol name and description */
	
    proto_lanforge = proto_register_protocol("LANforge Traffic Generator", "LANforge", "lanforge");
	
    /* Required function calls to register the header fields and subtrees used */
	
    proto_register_field_array(proto_lanforge, hf, array_length(hf));
    proto_register_subtree_array(ett, array_length(ett));
}


void proto_reg_handoff_lanforge(void)
{
    /* Register as a heuristic UDP dissector */
    heur_dissector_add("udp", dissect_lanforge, proto_lanforge);
    heur_dissector_add("tcp", dissect_lanforge, proto_lanforge); 

    /* Find data dissector handle */
    data_handle = find_dissector("data");
}
