epan/dissectors/packet-msn-messenger.c

   1 /* packet-msn-messenger.c
   2  * Routines for MSN Messenger Service packet dissection
   3  * Copyright 2003, Chris Waters <chris@waters.co.nz>
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * Copied from packet-pop.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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  26  */
  27
  28 #include "config.h"
  29
  30 #include <glib.h>
  31 #include <epan/packet.h>
  32 #include <epan/strutil.h>
  33
  34 /*
  35  * The now-expired Internet-Draft for the MSN Messenger 1.0 protocol
  36  * can, as of the time of the writing of this comment, be found at:
  37  *
  38  *      http://praya.sourceforge.net/draft-movva-msn-messenger-protocol-00.txt
  39  *
  40  *      http://mono.es.gnome.org/imsharp/tutoriales/msn/appendixa.html
  41  *
  42  *      http://www.hypothetic.org/docs/msn/ietf_draft.php
  43  *
  44  *      http://babble.wundsam.net/docs/protocol-msn-im.txt
  45  *
  46  * Note that it's Yet Another FTP-Like Command/Response Protocol,
  47  * so it arguably should be dissected as such, although you do have
  48  * to worry about the MSG command, as only the first line of it
  49  * should be parsed as a command, the rest should be parsed as the
  50  * message body.  We therefore leave "hf_msnms_command", "tokenlen",
  51  * and "next_token", even though they're unused, as reminders that
  52  * this should be done.
  53  */
  54
  55 static int proto_msnms = -1;
  56 /* static int hf_msnms_command = -1; */
  57
  58 static gint ett_msnms = -1;
  59
  60 #define TCP_PORT_MSNMS                  1863
  61
  62 static void
  63 dissect_msnms(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  64 {
  65         proto_tree      *msnms_tree;
  66         proto_item      *ti;
  67         gint            offset = 0;
  68         const guchar    *line;
  69         gint            next_offset;
  70         int             linelen;
  71         /* int          tokenlen; */
  72         /* const guchar *next_token; */
  73
  74         col_set_str(pinfo->cinfo, COL_PROTOCOL, "MSNMS");
  75
  76         /*
  77          * Find the end of the first line.
  78          *
  79          * Note that "tvb_find_line_end()" will return a value that is
  80          * not longer than what's in the buffer, so the "tvb_get_ptr()"
  81          * call won't throw an exception.
  82          */
  83         linelen = tvb_find_line_end(tvb, offset, -1, &next_offset, FALSE);
  84         line = tvb_get_ptr(tvb, offset, linelen);
  85
  86
  87         /*
  88          * Put the first line from the buffer into the summary.
  89          */
  90         col_add_str(pinfo->cinfo, COL_INFO,
  91                             format_text(line, linelen));
  92
  93         if (tree) {
  94                 ti = proto_tree_add_item(tree, proto_msnms, tvb, offset, -1,
  95                     ENC_NA);
  96                 msnms_tree = proto_item_add_subtree(ti, ett_msnms);
  97
  98                 /*
  99                  * Show the rest of the packet as text,
 100                  * a line at a time.
 101                  */
 102                 while (tvb_offset_exists(tvb, offset)) {
 103                         /*
 104                          * Find the end of the line.
 105                          */
 106                         tvb_find_line_end(tvb, offset, -1,
 107                             &next_offset, FALSE);
 108
 109                         /*
 110                          * Put this line.
 111                          */
 112                         proto_tree_add_text(msnms_tree, tvb, offset,
 113                             next_offset - offset, "%s",
 114                             tvb_format_text(tvb, offset, next_offset - offset));
 115                         offset = next_offset;
 116                 }
 117         }
 118 }
 119
 120 void
 121 proto_register_msnms(void)
 122 {
 123   static gint *ett[] = {
 124     &ett_msnms,
 125   };
 126
 127   proto_msnms = proto_register_protocol("MSN Messenger Service", "MSNMS", "msnms");
 128   proto_register_subtree_array(ett, array_length(ett));
 129 }
 130
 131 void
 132 proto_reg_handoff_msnms(void)
 133 {
 134   dissector_handle_t msnms_handle;
 135
 136   msnms_handle = create_dissector_handle(dissect_msnms, proto_msnms);
 137   dissector_add_uint("tcp.port", TCP_PORT_MSNMS, msnms_handle);
 138   /*
 139    * For MSN Messenger Protocol over HTTP
 140    */
 141   dissector_add_string("media_type", "application/x-msn-messenger", msnms_handle);
 142 }