epan/dissectors/packet-time.c

   1 /* packet-time.c
   2  * Routines for Time Protocol (RFC 868) packet dissection
   3  *
   4  * Richard Sharpe <rsharpe@ns.aus.com>
   5  *
   6  * $Id$
   7  *
   8  * Wireshark - Network traffic analyzer
   9  * By Gerald Combs <gerald@wireshark.org>
  10  * Copyright 1998 Gerald Combs
  11  *
  12  * Copied from packet-tftp.c
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  27  */
  28
  29 #include "config.h"
  30
  31 #include <epan/packet.h>
  32 #include <epan/prefs.h>
  33
  34
  35 static const enum_val_t time_display_types[] = {
  36     { "UTC", "UTC", ABSOLUTE_TIME_UTC },
  37     { "Local", "Local", ABSOLUTE_TIME_LOCAL},
  38     { NULL, NULL, 0 }
  39 };
  40
  41 static int proto_time = -1;
  42 static int hf_time_time = -1;
  43
  44 static gint ett_time = -1;
  45 static absolute_time_display_e time_display_type = ABSOLUTE_TIME_LOCAL;
  46
  47 /* This dissector works for TCP and UDP time packets */
  48 #define TIME_PORT 37
  49
  50 static void
  51 dissect_time(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  52 {
  53   proto_tree    *time_tree;
  54   proto_item    *ti;
  55
  56   col_set_str(pinfo->cinfo, COL_PROTOCOL, "TIME");
  57
  58   col_add_fstr(pinfo->cinfo, COL_INFO, "TIME %s",
  59                  pinfo->srcport == pinfo->match_uint ? "Response":"Request");
  60
  61   if (tree) {
  62
  63     ti = proto_tree_add_item(tree, proto_time, tvb, 0, -1, ENC_NA);
  64     time_tree = proto_item_add_subtree(ti, ett_time);
  65
  66     proto_tree_add_text(time_tree, tvb, 0, 0,
  67                         pinfo->srcport==TIME_PORT ? "Type: Response":"Type: Request");
  68     if (pinfo->srcport == TIME_PORT) {
  69       /* seconds since 1900-01-01 00:00:00 GMT, *not* 1970 */
  70       guint32 delta_seconds = tvb_get_ntohl(tvb, 0);
  71       proto_tree_add_uint_format(time_tree, hf_time_time, tvb, 0, 4,
  72                                  delta_seconds, "%s",
  73                                  abs_time_secs_to_str(delta_seconds-2208988800U, time_display_type, TRUE));
  74     }
  75   }
  76 }
  77
  78 void
  79 proto_register_time(void)
  80 {
  81
  82   static hf_register_info hf[] = {
  83     { &hf_time_time,
  84       { "Time", "time.time",
  85         FT_UINT32, BASE_DEC, NULL, 0x0,
  86         "Seconds since 00:00 (midnight) 1 January 1900 GMT", HFILL }}
  87   };
  88   static gint *ett[] = {
  89     &ett_time,
  90   };
  91
  92   module_t *time_pref ;
  93
  94   proto_time = proto_register_protocol("Time Protocol", "TIME", "time");
  95   proto_register_field_array(proto_time, hf, array_length(hf));
  96   proto_register_subtree_array(ett, array_length(ett));
  97
  98   time_pref = prefs_register_protocol(proto_time, NULL);
  99   prefs_register_enum_preference(time_pref,
 100                                        "display_time_type",
 101                                        "Time Display",
 102                                        "Time display type",
 103                                        (gint *)&time_display_type,
 104                                        time_display_types,
 105                                        FALSE);
 106
 107 }
 108
 109 void
 110 proto_reg_handoff_time(void)
 111 {
 112   dissector_handle_t time_handle;
 113
 114   time_handle = create_dissector_handle(dissect_time, proto_time);
 115   dissector_add_uint("udp.port", TIME_PORT, time_handle);
 116   dissector_add_uint("tcp.port", TIME_PORT, time_handle);
 117 }