packet-ntp.c

   1 /* packet-ntp.c
   2  * Routines for NTP packet dissection
   3  * Copyright 1999, Nathan Neulinger <nneul@umr.edu>
   4  *
   5  * $Id: packet-ntp.c,v 1.1 1999/10/14 05:10:30 guy Exp $
   6  *
   7  * Ethereal - Network traffic analyzer
   8  * By Gerald Combs <gerald@unicom.net>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * Copied from packet-tftp.c
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  26  */
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <stdio.h>
  33
  34 #ifdef HAVE_SYS_TYPES_H
  35 # include <sys/types.h>
  36 #endif
  37
  38 #ifdef HAVE_NETINET_IN_H
  39 # include <netinet/in.h>
  40 #endif
  41
  42 #include <string.h>
  43 #include <glib.h>
  44 #include "packet.h"
  45 #include "packet-ntp.h"
  46
  47 static int proto_ntp = -1;
  48 static int hf_ntp_flags = -1;
  49 static int hf_ntp_stratum = -1;
  50 static int hf_ntp_ppoll = -1;
  51 static int hf_ntp_precision = -1;
  52 static int hf_ntp_rootdelay = -1;
  53 static int hf_ntp_rootdispersion = -1;
  54 static int hf_ntp_refid = -1;
  55 static int hf_ntp_reftime = -1;
  56 static int hf_ntp_org = -1;
  57 static int hf_ntp_rec = -1;
  58 static int hf_ntp_xmt = -1;
  59 static int hf_ntp_keyid = -1;
  60 static int hf_ntp_mac = -1;
  61
  62 void
  63 dissect_ntp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree)
  64 {
  65         proto_tree      *ntp_tree, *ti;
  66         struct ntp_packet *pkt;
  67
  68         /* get at least a full packet structure */
  69         if ( !BYTES_ARE_IN_FRAME(offset, 48) ) /* 48 without keyid or mac */
  70                 return;
  71
  72         pkt = (struct ntp_packet *) &pd[offset];
  73
  74         if (check_col(fd, COL_PROTOCOL))
  75                 col_add_str(fd, COL_PROTOCOL, "NTP");
  76
  77         if (check_col(fd, COL_INFO))
  78                 col_add_str(fd, COL_INFO, "NTP");
  79
  80         if (tree) {
  81                 ti = proto_tree_add_item(tree, proto_ntp, offset, END_OF_FRAME, NULL);
  82                 ntp_tree = proto_item_add_subtree(ti, ETT_NTP);
  83
  84                 proto_tree_add_item(ntp_tree, hf_ntp_flags, offset, 1, pkt->flags);
  85                 proto_tree_add_item(ntp_tree, hf_ntp_stratum, offset+1, 1, pkt->stratum);
  86                 proto_tree_add_item(ntp_tree, hf_ntp_ppoll, offset+2, 1, pkt->ppoll);
  87                 proto_tree_add_item(ntp_tree, hf_ntp_precision, offset+3, 1, pkt->precision);
  88                 proto_tree_add_item(ntp_tree, hf_ntp_rootdelay, offset+4, 4, pkt->rootdelay);
  89                 proto_tree_add_item(ntp_tree, hf_ntp_rootdispersion, offset+8, 4, pkt->rootdispersion);
  90                 proto_tree_add_item(ntp_tree, hf_ntp_refid, offset+12, 4, pkt->refid);
  91                 proto_tree_add_item(ntp_tree, hf_ntp_reftime, offset+16, 8, pkt->reftime);
  92                 proto_tree_add_item(ntp_tree, hf_ntp_org, offset+24, 8, pkt->org);
  93                 proto_tree_add_item(ntp_tree, hf_ntp_rec, offset+32, 8, pkt->rec);
  94                 proto_tree_add_item(ntp_tree, hf_ntp_xmt, offset+40, 8, pkt->xmt);
  95
  96                 if ( BYTES_ARE_IN_FRAME(offset, 50) )
  97                         proto_tree_add_item(ntp_tree, hf_ntp_keyid, offset+48, 4, pkt->keyid);
  98                 if ( BYTES_ARE_IN_FRAME(offset, 53) )
  99                         proto_tree_add_item(ntp_tree, hf_ntp_mac, offset+52, END_OF_FRAME, pkt->mac);
 100         }
 101 }
 102
 103 void
 104 proto_register_ntp(void)
 105 {
 106         static hf_register_info hf[] = {
 107                         { &hf_ntp_flags, {
 108                                 "Flags", "ntp.flags", FT_BYTES, BASE_HEX,
 109                                 NULL, 0, "Flags (Leap/Version/Mode)" }},
 110                         { &hf_ntp_stratum, {
 111                                 "Peer Clock Stratum", "ntp.stratum", FT_BYTES, BASE_HEX,
 112                                 NULL, 0, "Peer Clock Stratum" }},
 113                         { &hf_ntp_ppoll, {
 114                                 "Peer Polling Interval", "ntp.ppoll", FT_BYTES, BASE_HEX,
 115                                 NULL, 0, "Peer Polling Interval" }},
 116                         { &hf_ntp_precision, {
 117                                 "Peer Clock Precision", "ntp.precision", FT_BYTES, BASE_HEX,
 118                                 NULL, 0, "Peer Clock Precision" }},
 119                         { &hf_ntp_rootdelay, {
 120                                 "Distance to Primary", "ntp.rootdelay", FT_BYTES, BASE_HEX,
 121                                 NULL, 0, "Distance to Primary" }},
 122                         { &hf_ntp_rootdispersion, {
 123                                 "Clock Dispersion", "ntp.rootdispersion", FT_BYTES, BASE_HEX,
 124                                 NULL, 0, "Clock Dispersion" }},
 125                         { &hf_ntp_refid, {
 126                                 "Reference Clock ID", "ntp.refid", FT_BYTES, BASE_HEX,
 127                                 NULL, 0, "Reference Clock ID" }},
 128                         { &hf_ntp_reftime, {
 129                                 "Reference Clock Update Time", "ntp.reftime", FT_BYTES, BASE_HEX,
 130                                 NULL, 0, "Reference Clock Update Time" }},
 131                         { &hf_ntp_org, {
 132                                 "Originate Time Stamp", "ntp.org", FT_BYTES, BASE_HEX,
 133                                 NULL, 0, "Originate Time Stamp" }},
 134                         { &hf_ntp_rec, {
 135                                 "Receive Time Stamp", "ntp.rec", FT_BYTES, BASE_HEX,
 136                                 NULL, 0, "Receive Time Stamp" }},
 137                         { &hf_ntp_xmt, {
 138                                 "Transmit Time Stamp", "ntp.xmt", FT_BYTES, BASE_HEX,
 139                                 NULL, 0, "Transmit Time Stamp" }},
 140                         { &hf_ntp_keyid, {
 141                                 "Key ID", "ntp.keyid", FT_BYTES, BASE_HEX,
 142                                 NULL, 0, "Key ID" }},
 143                         { &hf_ntp_mac, {
 144                                 "Message Authentication Code", "ntp.mac", FT_BYTES, BASE_HEX,
 145                                 NULL, 0, "Message Authentication Code" }},
 146         };
 147
 148         proto_ntp = proto_register_protocol("Network Time Protocol", "ntp");
 149         proto_register_field_array(proto_ntp, hf, array_length(hf));
 150 }