epan/dissectors/packet-uts.c

   1 /* packet-uts.c
   2  * Routines for UTS WAN protocol dissection
   3  * Copyright 2007, Fulko Hew, SITA INC Canada, Inc.
   4  *
   5  * $Id$
   6  *
   7  * Copied from packet-ipars.c
   8  *
   9  * Wireshark - Network traffic analyzer
  10  * By Gerald Combs <gerald@wireshark.org>
  11  * Copyright 1998 Gerald Combs
  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 /* Use tabstops = 4 */
  29
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include <glib.h>
  35 #include <string.h>
  36 #include <epan/packet.h>
  37 #include <epan/emem.h>
  38
  39 #define SOH             (0x01)
  40 #define STX             (0x02)
  41 #define ETX             (0x03)
  42 #define EOT             (0x04)
  43 #define ENQ             (0x05)
  44 #define BEL             (0x07)
  45 #define NAK             (0x15)
  46 #define DLE             (0x10)
  47
  48 #define GRID    (0x20)
  49 #define GSID    (0x50)
  50 #define GDID    (0x70)
  51
  52 #define MAX_POLL_TYPE_MSG_SIZE  (50)
  53
  54 static int              proto_uts                       = -1;
  55 static gint             ett_uts                         = -1;
  56 static gint             ett_header_uts          = -1;
  57 static gint             ett_trailer_uts         = -1;
  58 static int              hf_rid                          = -1;
  59 static int              hf_sid                          = -1;
  60 static int              hf_did                          = -1;
  61 static int              hf_retxrequest          = -1;
  62 static int              hf_ack                          = -1;
  63 static int              hf_replyrequest         = -1;
  64 static int              hf_busy                         = -1;
  65 static int              hf_notbusy                      = -1;
  66 static int              hf_msgwaiting           = -1;
  67 static int              hf_function                     = -1;
  68 static int              hf_data                         = -1;
  69
  70 #define MATCH   (1)
  71 #define FETCH   (2)
  72
  73 #define SRC             (1)
  74 #define DST             (2)
  75
  76 static int testchar(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, int op, gchar match, gchar *storage)
  77 {
  78         gchar temp;
  79
  80         if (tvb_length_remaining(tvb, offset)) {
  81                 temp = tvb_get_guint8(tvb, offset) & 0x7f;
  82                 if (op == FETCH || (op == MATCH && temp == match)) {
  83                         if (storage != NULL) *storage = temp;
  84                         return 1;
  85                 } else {
  86                         return 0;
  87                 }
  88         } else {
  89                 if (check_col(pinfo->cinfo, COL_INFO))
  90                         col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown Message Format");
  91                 return 0;
  92         }
  93 }
  94
  95 static void
  96 set_addr(packet_info *pinfo _U_ , int field, gchar rid, gchar sid, gchar did)
  97 {
  98         if (field == SRC) {
  99                 if (check_col(pinfo->cinfo, COL_DEF_SRC)) col_append_fstr(pinfo->cinfo, COL_DEF_SRC, " %2.2X:%2.2X:%2.2X", rid, sid, did);
 100         } else {
 101                 if (check_col(pinfo->cinfo, COL_DEF_DST)) col_append_fstr(pinfo->cinfo, COL_DEF_DST, " %2.2X:%2.2X:%2.2X", rid, sid, did);
 102         }
 103 }
 104
 105 static void
 106 dissect_uts(tvbuff_t *tvb, packet_info *pinfo _U_ , proto_tree *tree)
 107 {
 108         proto_tree      *uts_tree                       = NULL;
 109         proto_tree      *uts_header_tree        = NULL;
 110         proto_tree      *uts_trailer_tree       = NULL;
 111         proto_item      *ti;
 112         int                     length;
 113         gchar           rid, sid, did;
 114         gchar           *msg_msg;
 115         int                     offset                          = 0;
 116         int                     header_length           = -1;
 117         int                     ack_start                       = 0;
 118         int                     busy_start                      = 0;
 119         int                     notbusy_start           = 0;
 120         int                     replyrequest_start      = 0;
 121         int                     function_start          = 0;
 122         int                     msgwaiting_start        = 0;
 123         int                     nak_start                       = 0;
 124         int                     etx_start                       = 0;
 125         int                     bcc_start                       = 0;
 126         int                     stx_start                       = 0;
 127         gchar           function_code;
 128         guint8          *data_ptr;
 129
 130         enum    { NOTRAFFIC, OTHER }    msg_type = OTHER;
 131
 132         msg_msg         = ep_alloc(MAX_POLL_TYPE_MSG_SIZE);
 133         msg_msg[0]      = 0;
 134
 135         if (check_col(pinfo->cinfo, COL_PROTOCOL))                      /* set the protocol column on summary display */
 136                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "UTS");
 137
 138         if (testchar(tvb, pinfo, 0, MATCH, EOT, NULL)   &&
 139                 testchar(tvb, pinfo, 1, MATCH, EOT, NULL)       &&
 140                 testchar(tvb, pinfo, 2, MATCH, ETX, NULL)) {
 141                 msg_type = NOTRAFFIC;
 142                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "No Traffic");
 143         } else {
 144                 if (testchar(tvb, pinfo, 0, MATCH, SOH, NULL)   &&
 145                         testchar(tvb, pinfo, 1, FETCH, 0, (gchar *)&rid)        &&
 146                         testchar(tvb, pinfo, 2, FETCH, 0, (gchar *)&sid)        &&
 147                         testchar(tvb, pinfo, 3, FETCH, 0, (gchar *)&did)) {
 148                                 offset = 4;
 149                                 if (testchar(tvb, pinfo, offset, MATCH, ETX, NULL)) {
 150                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "General Poll");
 151                                         set_addr(pinfo, DST, rid, sid, did);
 152                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)       &&
 153                                                         testchar(tvb, pinfo, offset+1, MATCH, '1', NULL)        &&
 154                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)) {
 155                                                                 ack_start = offset;
 156                                                                 if (sid == GSID && did == GDID) {
 157                                                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "General Poll + ACK");
 158                                                                         set_addr(pinfo, DST, rid, sid, did);
 159                                                                 } else if (sid != GSID && did == GDID) {
 160                                                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Specific Poll + ACK");
 161                                                                         set_addr(pinfo, DST, rid, sid, did);
 162                                                                 } else if (sid != GSID && did != GDID) {
 163                                                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "No Traffic + ACK");
 164                                                                         set_addr(pinfo, SRC, rid, sid, did);
 165                                                                 } else {
 166                                                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Unknown Message Format");
 167                                                                         if ((pinfo->pseudo_header->sita.flags & SITA_FRAME_DIR) == SITA_FRAME_DIR_TXED) {
 168                                                                                 set_addr(pinfo, DST, rid, sid, did);    /* if the ACN sent it, the address is of the destination... the terminal */
 169                                                                         } else {
 170                                                                                 set_addr(pinfo, SRC, rid, sid, did);    /* if the ACN received it, the address if of the source... the terminal */
 171                                                                         }
 172                                                                 }
 173                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 174                                                         testchar(tvb, pinfo, offset+1, MATCH, NAK, NULL)        &&
 175                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)        &&
 176                                                         sid != GSID && did == GDID) {
 177                                                                 nak_start = offset;
 178                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Retransmit Request");
 179                                                                 set_addr(pinfo, DST, rid, sid, did);
 180                                 } else if (testchar(tvb, pinfo, offset, MATCH, BEL, NULL)               &&
 181                                                         testchar(tvb, pinfo, offset+1, MATCH, STX, NULL)        &&
 182                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)) {
 183                                                                 header_length = offset+2;
 184                                                                 msgwaiting_start = offset;
 185                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Message Waiting");
 186                                                                 set_addr(pinfo, DST, rid, sid, did);
 187                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 188                                                         testchar(tvb, pinfo, offset+1, MATCH, '1', NULL)        &&
 189                                                         testchar(tvb, pinfo, offset+2, MATCH, STX, NULL)) {
 190                                                                 ack_start = offset;
 191                                                                 header_length = offset+3;
 192                                                                 stx_start = offset+2;
 193                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Text + ACK");
 194                                                                 set_addr(pinfo, SRC, rid, sid, did);
 195                                 } else if (testchar(tvb, pinfo, offset, MATCH, STX, NULL)) {
 196                                         header_length = offset+1;
 197                                         stx_start = offset;
 198                                         g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Text");
 199                                         if ((pinfo->pseudo_header->sita.flags & SITA_FRAME_DIR) == SITA_FRAME_DIR_TXED) {
 200                                                 set_addr(pinfo, DST, rid, sid, did);            /* if the ACN sent it, the address is of the destination... the terminal */
 201                                         } else {
 202                                                 set_addr(pinfo, SRC, rid, sid, did);            /* if the ACN received it, the address if of the source... the terminal */
 203                                         }
 204                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 205                                                         testchar(tvb, pinfo, offset+1, MATCH, ENQ, NULL)        &&
 206                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)) {
 207                                                                 replyrequest_start = offset;
 208                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Reply Request");
 209                                                                 set_addr(pinfo, SRC, rid, sid, did);
 210                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 211                                                         testchar(tvb, pinfo, offset+1, MATCH, '?', NULL)        &&
 212                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)) {
 213                                                                 busy_start = offset;
 214                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Busy");
 215                                                                 set_addr(pinfo, SRC, rid, sid, did);
 216                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 217                                                         testchar(tvb, pinfo, offset+1, MATCH, ';', NULL)        &&
 218                                                         testchar(tvb, pinfo, offset+2, MATCH, ETX, NULL)) {
 219                                                                 notbusy_start = offset;
 220                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Not Busy");
 221                                                                 set_addr(pinfo, SRC, rid, sid, did);
 222                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)               &&
 223                                                         testchar(tvb, pinfo, offset+1, MATCH, '1', NULL)        &&
 224                                                         testchar(tvb, pinfo, offset+2, MATCH, DLE, NULL)        &&
 225                                                         testchar(tvb, pinfo, offset+3, MATCH, ';', NULL)        &&
 226                                                         testchar(tvb, pinfo, offset+4, MATCH, ETX, NULL)) {
 227                                                                 notbusy_start = offset+2;
 228                                                                 ack_start = offset;
 229                                                                 g_snprintf(msg_msg, MAX_POLL_TYPE_MSG_SIZE, "Not Busy + ACK");
 230                                                                 set_addr(pinfo, SRC, rid, sid, did);
 231                                 } else if (testchar(tvb, pinfo, offset, MATCH, DLE, NULL)                               &&
 232                                                         testchar(tvb, pinfo, offset+1, MATCH, '1', NULL)                        &&
 233                                                         testchar(tvb, pinfo, offset+2, FETCH, 0, &function_code)        &&
 234                                                         testchar(tvb, pinfo, offset+3, MATCH, ETX, NULL)) {
 235                                                                 ack_start = offset;
 236                                                                 function_start = offset + 2;
 237                                                                 if (check_col(pinfo->cinfo, COL_INFO))
 238                                                                         col_add_fstr(pinfo->cinfo, COL_INFO, "Function Message '%c' + ACK", function_code);
 239                                                                 set_addr(pinfo, SRC, rid, sid, did);
 240                                 } else if (testchar(tvb, pinfo, offset, FETCH, 0, &function_code)               &&
 241                                                         testchar(tvb, pinfo, offset+1, MATCH, ETX, NULL)) {
 242                                                                 function_start = offset;
 243                                                                 if (check_col(pinfo->cinfo, COL_INFO))
 244                                                                         col_add_fstr(pinfo->cinfo, COL_INFO, "Function Message '%c'", function_code);
 245                                                                 set_addr(pinfo, SRC, rid, sid, did);
 246                                 }
 247                         }
 248         }
 249         if ((check_col(pinfo->cinfo, COL_INFO)) && strlen(msg_msg))
 250                 col_add_str(pinfo->cinfo, COL_INFO, msg_msg);
 251
 252         while (tvb_length_remaining(tvb, offset)) {                                     /* now look for the ETX */
 253                 if ((tvb_get_guint8(tvb, offset) & 0x7f) == ETX) {
 254                         if (header_length == -1) header_length = offset;        /* the header ends at an STX, or if not found, the ETX */
 255                         etx_start = offset;
 256                         offset++;
 257                         break;
 258                 }
 259                 offset++;
 260         }
 261         if (tvb_length_remaining(tvb, offset))                                          /* if there is anything left, it could be the BCC and pads */
 262                 bcc_start = offset;
 263
 264         if (tree) {
 265                 ti = proto_tree_add_protocol_format(tree, proto_uts, tvb, 0, -1, "UTS");
 266                 uts_tree = proto_item_add_subtree(ti, ett_uts);
 267
 268                 if (msg_type == NOTRAFFIC) {
 269                         proto_tree_add_protocol_format(uts_tree, proto_uts, tvb, 0, 2, "No Traffic");
 270                         proto_tree_add_protocol_format(uts_tree, proto_uts, tvb, 2, -1, "ETX + padding");
 271                 } else {
 272                         ti = proto_tree_add_text(uts_tree, tvb, 0, header_length, "Header");
 273                         uts_header_tree = proto_item_add_subtree(ti, ett_header_uts);
 274
 275                         proto_tree_add_protocol_format(uts_header_tree, proto_uts, tvb, 0, 1, "SOH");
 276
 277                         if (rid == GRID)                proto_tree_add_uint_format(uts_header_tree, hf_rid, tvb, 1, 1, rid, "RID (%02X) (General)",     rid     );
 278                         else                                    proto_tree_add_uint_format(uts_header_tree, hf_rid, tvb, 1, 1, rid, "RID (%02X)",                       rid     );
 279                         if (sid == GSID)                proto_tree_add_uint_format(uts_header_tree, hf_sid, tvb, 2, 1, sid, "SID (%02X) (General)",     sid     );
 280                         else                                    proto_tree_add_uint_format(uts_header_tree, hf_sid, tvb, 2, 1, sid, "SID (%02X)",                       sid     );
 281                         if (sid == GDID)                proto_tree_add_uint_format(uts_header_tree, hf_did, tvb, 3, 1, did, "DID (%02X) (General)",     did     );
 282                         else                                    proto_tree_add_uint_format(uts_header_tree, hf_did, tvb, 3, 1, did, "DID (%02X)",                       did     );
 283
 284                         if (nak_start)                  proto_tree_add_boolean_format(uts_header_tree, hf_retxrequest,  tvb, nak_start,                         2, 1, "Re-transmit Request");
 285                         if (ack_start)                  proto_tree_add_boolean_format(uts_header_tree, hf_ack,                  tvb, ack_start,                         2, 1, "Ack");
 286                         if (replyrequest_start) proto_tree_add_boolean_format(uts_header_tree, hf_replyrequest, tvb, replyrequest_start,        2, 1, "Reply Request");
 287                         if (busy_start)                 proto_tree_add_boolean_format(uts_header_tree, hf_busy,                 tvb, busy_start,                        2, 1, "Busy");
 288                         if (notbusy_start)              proto_tree_add_boolean_format(uts_header_tree, hf_notbusy,              tvb, notbusy_start,                     2, 1, "Not Busy");
 289                         if (msgwaiting_start)   proto_tree_add_boolean_format(uts_header_tree, hf_msgwaiting,   tvb, msgwaiting_start,          1, 1, "Message Waiting");
 290                         if (function_start)
 291                                 proto_tree_add_uint_format(uts_header_tree, hf_function, tvb, function_start, 1, function_code, "Function '%c'", function_code  );
 292
 293                         if (stx_start) {
 294                                 proto_tree_add_protocol_format(uts_header_tree, proto_uts, tvb, stx_start,                      1, "Start of Text"                      );
 295                                 length = tvb_length_remaining(tvb, stx_start+1);                                        /* find out how much message remains */
 296                                 if (etx_start) length = (etx_start - stx_start - 1);                            /* and the data part is the rest... whatever preceeds the ETX if it exists */
 297                                 data_ptr = tvb_get_ephemeral_string(tvb, stx_start+1, length);  /* copy the string for dissecting */
 298                                 proto_tree_add_string_format(uts_tree, hf_data, tvb, stx_start + 1, length, data_ptr, "Text (%d byte%s)", length, plurality(length, "", "s"));
 299                         }
 300                         if (etx_start) {
 301                                 ti = proto_tree_add_text(uts_tree, tvb, etx_start, -1, "Trailer");
 302                                 uts_trailer_tree = proto_item_add_subtree(ti, ett_trailer_uts);
 303
 304                                 if (etx_start)  proto_tree_add_protocol_format(uts_trailer_tree, proto_uts, tvb, etx_start,     1, "ETX"                                );
 305                                 if (bcc_start)  proto_tree_add_protocol_format(uts_trailer_tree, proto_uts, tvb, bcc_start,     -1, "CCC + padding"             );
 306                         }
 307                 }
 308         }
 309 }
 310
 311 void
 312 proto_register_uts(void)
 313 {
 314    static hf_register_info hf[] = {
 315         { &hf_rid,                      { "RID",                        "uts.rid",                      FT_UINT8,       BASE_HEX,       NULL, 0, "Remote Identifier address",   HFILL }},
 316         { &hf_sid,                      { "SID",                        "uts.sid",                      FT_UINT8,       BASE_HEX,       NULL, 0, "Site Identifier address",             HFILL }},
 317         { &hf_did,                      { "DID",                        "uts.did",                      FT_UINT8,       BASE_HEX,       NULL, 0, "Device Identifier address",   HFILL }},
 318                 { &hf_retxrequest,      { "ReTxRequst",         "uts.retxrequst",       FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Re-transmit Request", HFILL }},
 319                 { &hf_ack,                      { "Ack",                        "uts.ack",                      FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Ack",                                 HFILL }},
 320                 { &hf_replyrequest,     { "ReplyRequst",        "uts.replyrequest",     FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Reply Request",               HFILL }},
 321                 { &hf_busy,                     { "Busy",                       "uts.busy",                     FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Busy",                                HFILL }},
 322                 { &hf_notbusy,          { "NotBusy",            "uts.notbusy",          FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Not Busy",                    HFILL }},
 323                 { &hf_msgwaiting,       { "MsgWaiting",         "uts.msgwaiting",       FT_BOOLEAN,     BASE_NONE,      NULL, 0, "TRUE if Message Waiting",             HFILL }},
 324         { &hf_function,         { "Function",           "uts.function",         FT_UINT8,       BASE_HEX,       NULL, 0, "Function Code value",                 HFILL }},
 325                 { &hf_data,                     { "Data",                       "uts.data",                     FT_STRING,      BASE_NONE,      NULL, 0, "User Data Message",                   HFILL }},
 326     };
 327
 328         static gint *ett[] = {
 329                 &ett_uts,
 330                 &ett_header_uts,
 331                 &ett_trailer_uts,
 332         };
 333
 334         proto_uts = proto_register_protocol("Unisys Transmittal System", "UTS", "uts");         /* name, short name, abbrev */
 335         proto_register_field_array(proto_uts, hf, array_length(hf));
 336         proto_register_subtree_array(ett, array_length(ett));
 337         register_dissector("uts", dissect_uts, proto_uts);
 338 }