packet-xyplex.c

   1 /* packet-xyplex.c
   2  * Routines for xyplex packet dissection
   3  *
   4  * Copyright 2002 Randy McEoin <rmceoin@pe.com>
   5  *
   6  * $Id: packet-xyplex.c,v 1.2 2002/08/28 21:00:40 jmayer Exp $
   7  *
   8  * Ethereal - Network traffic analyzer
   9  * By Gerald Combs <gerald@ethereal.com>
  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  27  */
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <glib.h>
  34 #include <epan/packet.h>
  35 #include <epan/conversation.h>
  36
  37 static int proto_xyplex = -1;
  38 static int hf_xyplex_type = -1;
  39 static int hf_xyplex_pad = -1;
  40 static int hf_xyplex_server_port = -1;
  41 static int hf_xyplex_return_port = -1;
  42 static int hf_xyplex_reserved = -1;
  43 static int hf_xyplex_reply = -1;
  44
  45 static gint ett_xyplex = -1;
  46
  47 static dissector_handle_t xyplex_handle;
  48
  49 #define UDP_PORT_XYPLEX    173
  50
  51 #define XYPLEX_REG_OK           0x00
  52 #define XYPLEX_REG_QUEFULL      0x05
  53
  54 static const value_string xyplex_reg_vals[] = {
  55   { XYPLEX_REG_OK,      "OK" },
  56   { XYPLEX_REG_QUEFULL, "Queue Full" },
  57   { 0,          NULL }
  58 };
  59
  60 static void
  61 dissect_xyplex(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  62 {
  63         proto_tree      *xyplex_tree = NULL;
  64         proto_item      *ti;
  65         conversation_t  *conversation;
  66         gint            offset = 0;
  67
  68         guint8          prototype;
  69         guint8          padding;
  70         guint16         server_port;
  71         guint16         return_port;
  72         guint16         reserved;
  73         guint16         reply;
  74
  75         if (check_col(pinfo->cinfo, COL_PROTOCOL))
  76                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "XYPLEX");
  77
  78         if (tree) {
  79           ti = proto_tree_add_item(tree, proto_xyplex, tvb, offset, -1, FALSE);
  80           xyplex_tree = proto_item_add_subtree(ti, ett_xyplex);
  81         }
  82
  83         if (pinfo->destport == UDP_PORT_XYPLEX) {
  84                 /* This is a registration request from a Unix server
  85                  * to the Xyplex server.  The server_port indicates
  86                  * which Xyplex serial port is desired.  The
  87                  * return_port tells the Xyplex server what TCP port
  88                  * to open to the Unix server.
  89                  */
  90                 prototype = tvb_get_guint8(tvb, offset);
  91                 padding = tvb_get_guint8(tvb, offset+1);
  92                 server_port = tvb_get_ntohs(tvb, offset+2);
  93                 return_port = tvb_get_ntohs(tvb, offset+4);
  94                 reserved = tvb_get_ntohs(tvb, offset+6);
  95                 if (check_col(pinfo->cinfo, COL_INFO)) {
  96                   col_add_fstr(pinfo->cinfo, COL_INFO,
  97                           "Registration Request: %d Return: %d",
  98                           server_port, return_port);
  99                 }
 100                 if (tree) {
 101                   proto_tree_add_uint(xyplex_tree, hf_xyplex_type, tvb,
 102                                     offset, 1, prototype);
 103                   proto_tree_add_uint(xyplex_tree, hf_xyplex_pad, tvb,
 104                                     offset+1, 1, padding);
 105                   proto_tree_add_uint(xyplex_tree, hf_xyplex_server_port, tvb,
 106                                     offset+2, 2, server_port);
 107                   proto_tree_add_uint(xyplex_tree, hf_xyplex_return_port, tvb,
 108                                     offset+4, 2, return_port);
 109                   proto_tree_add_uint(xyplex_tree, hf_xyplex_reserved, tvb,
 110                                     offset+6, 2, reserved);
 111                 }
 112                 offset += 8;
 113
 114                 /* Look for all future TCP conversations between the
 115                  * requestiong server and the Xyplex host using the
 116                  * return_port.
 117                  */
 118                 conversation = find_conversation(&pinfo->src, &pinfo->dst,
 119                                   PT_TCP, return_port, 0, NO_PORT_B);
 120                 if (conversation == NULL) {
 121                     conversation = conversation_new(&pinfo->src, &pinfo->dst,
 122                                     PT_TCP, return_port, 0, NO_PORT2);
 123                     conversation_set_dissector(conversation, xyplex_handle);
 124                 }
 125                 return;
 126         }
 127
 128         if (pinfo->srcport == UDP_PORT_XYPLEX) {
 129                 prototype = tvb_get_guint8(tvb, offset);
 130                 padding = tvb_get_guint8(tvb, offset+1);
 131                 reply = tvb_get_ntohs(tvb, offset+2);
 132                 if (check_col(pinfo->cinfo, COL_INFO)) {
 133                   col_add_fstr(pinfo->cinfo, COL_INFO, "Registration Reply: %s",
 134                         val_to_str(reply, xyplex_reg_vals, "Unknown (0x%02x)"));
 135                 }
 136                 if (tree) {
 137                   proto_tree_add_uint(xyplex_tree, hf_xyplex_type, tvb,
 138                                     offset, 1, prototype);
 139                   proto_tree_add_uint(xyplex_tree, hf_xyplex_pad, tvb,
 140                                     offset+1, 1, padding);
 141                   proto_tree_add_uint(xyplex_tree, hf_xyplex_reply, tvb,
 142                                     offset+2, 2, reply);
 143                 }
 144                 offset += 4;
 145                 return;
 146         }
 147
 148         /*
 149          * This must be the TCP data stream.  This will just be
 150          * the raw data being transfered from the remote server
 151          * and the Xyplex serial port.
 152          */
 153         if (check_col(pinfo->cinfo, COL_INFO)) {
 154           col_add_fstr(pinfo->cinfo, COL_INFO, "%d > %d Data",
 155                   pinfo->srcport, pinfo->destport);
 156         }
 157         if (tree) {
 158           proto_tree_add_text(xyplex_tree, tvb, offset, -1,
 159                 "Data (%d bytes)", tvb_reported_length_remaining(tvb, offset));
 160         }
 161 }
 162
 163
 164 void
 165 proto_register_xyplex(void)
 166 {
 167   static hf_register_info hf[] = {
 168     { &hf_xyplex_type,
 169       { "Type",       "xyplex.type",
 170         FT_UINT8, BASE_DEC, NULL, 0x0,
 171         "Protocol type", HFILL }},
 172
 173     { &hf_xyplex_pad,
 174       { "Pad",        "xyplex.pad",
 175         FT_UINT8, BASE_DEC, NULL, 0x0,
 176         "Padding", HFILL }},
 177
 178     { &hf_xyplex_server_port,
 179       { "Server Port",        "xyplex.server_port",
 180         FT_UINT16, BASE_DEC, NULL, 0x0,
 181         "Server port", HFILL }},
 182
 183     { &hf_xyplex_return_port,
 184       { "Return Port",   "xyplex.return_port",
 185         FT_UINT16, BASE_DEC, NULL, 0x0,
 186         "Return port", HFILL }},
 187
 188     { &hf_xyplex_reserved,
 189       { "Reserved field",  "xyplex.reserved",
 190         FT_UINT16, BASE_DEC, NULL, 0x0,
 191         "Reserved field", HFILL }},
 192
 193     { &hf_xyplex_reply,
 194       { "Registration Reply",  "xyplex.reply",
 195         FT_UINT16, BASE_DEC, VALS(xyplex_reg_vals), 0x0,
 196         "Registration reply", HFILL }},
 197
 198   };
 199   static gint *ett[] = {
 200     &ett_xyplex,
 201   };
 202
 203   proto_xyplex = proto_register_protocol("Xyplex", "XYPLEX", "xyplex");
 204   proto_register_field_array(proto_xyplex, hf, array_length(hf));
 205   proto_register_subtree_array(ett, array_length(ett));
 206
 207   xyplex_handle = create_dissector_handle(dissect_xyplex, proto_xyplex);
 208 }
 209
 210 void
 211 proto_reg_handoff_xyplex(void)
 212 {
 213   dissector_add("udp.port", UDP_PORT_XYPLEX, xyplex_handle);
 214 }
 215