packet-sccpmg.c

   1 /* packet-sccp.c
   2  * Routines for Signalling Connection Control Part (SCCP) Management dissection
   3  * It is hopefully compliant to:
   4  *   ANSI T1.112.3-1996
   5  *   ITU-T Q.713 7/1996
   6  *
   7  * Copyright 2002, Jeff Morriss <jeff.morriss[AT]ulticom.com>
   8  *
   9  * $Id: packet-sccpmg.c,v 1.1 2002/09/20 09:22:46 sahlberg Exp $
  10  *
  11  * Ethereal - Network traffic analyzer
  12  * By Gerald Combs <gerald@ethereal.com>
  13  * Copyright 1998 Gerald Combs
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
  17  * as published by the Free Software Foundation; either version 2
  18  * of the License, or (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  * GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  28  */
  29
  30 #ifdef HAVE_CONFIG_H
  31 # include "config.h"
  32 #endif
  33
  34 #include "epan/packet.h"
  35 #include "packet-mtp3.h"
  36
  37 #define SCCPMG_SSN 1
  38
  39 #define SCCPMG_MESSAGE_TYPE_SSA 0x01
  40 #define SCCPMG_MESSAGE_TYPE_SSP 0x02
  41 #define SCCPMG_MESSAGE_TYPE_SST 0x03
  42 #define SCCPMG_MESSAGE_TYPE_SOR 0x04
  43 #define SCCPMG_MESSAGE_TYPE_SOG 0x05
  44 /* SSC is ITU only */
  45 #define SCCPMG_MESSAGE_TYPE_SSC 0x06
  46 /* Below are ANSI only */
  47 #define SCCPMG_MESSAGE_TYPE_SBR 0xfd
  48 #define SCCPMG_MESSAGE_TYPE_SNR 0xfe
  49 #define SCCPMG_MESSAGE_TYPE_SRT 0xff
  50
  51 /* Same as below but with names typed out */
  52 static const value_string sccpmg_message_type_values[] = {
  53   { SCCPMG_MESSAGE_TYPE_SSA,   "SubSystem Allowed" },
  54   { SCCPMG_MESSAGE_TYPE_SSP,   "SubSystem Prohibited" },
  55   { SCCPMG_MESSAGE_TYPE_SST,   "Subsystem Status Test" },
  56   { SCCPMG_MESSAGE_TYPE_SOR,   "Subsystem Out of service Request" },
  57   { SCCPMG_MESSAGE_TYPE_SOG,   "Subsystem Out of service Grant" },
  58   { SCCPMG_MESSAGE_TYPE_SSC,   "SubSystem Congested (ITU)" },
  59   { SCCPMG_MESSAGE_TYPE_SBR,   "Subsystem Backup Routing (ANSI)" },
  60   { SCCPMG_MESSAGE_TYPE_SNR,   "Subsystem Normal Routing (ANSI)" },
  61   { SCCPMG_MESSAGE_TYPE_SRT,   "Subsystem Routing status Test (ANSI)" },
  62   { 0,                       NULL } };
  63
  64 /* Same as above but in acronym for (for the Info column) */
  65 static const value_string sccpmg_message_type_acro_values[] = {
  66   { SCCPMG_MESSAGE_TYPE_SSA,   "SSA" },
  67   { SCCPMG_MESSAGE_TYPE_SSP,   "SSP" },
  68   { SCCPMG_MESSAGE_TYPE_SST,   "SST" },
  69   { SCCPMG_MESSAGE_TYPE_SOR,   "SOR" },
  70   { SCCPMG_MESSAGE_TYPE_SOG,   "SOG" },
  71   { SCCPMG_MESSAGE_TYPE_SSC,   "SSC" },
  72   { SCCPMG_MESSAGE_TYPE_SBR,   "SBR" },
  73   { SCCPMG_MESSAGE_TYPE_SNR,   "SNR" },
  74   { SCCPMG_MESSAGE_TYPE_SRT,   "SRT" },
  75   { 0,                       NULL } };
  76
  77
  78 #define SCCPMG_MESSAGE_TYPE_OFFSET 0
  79 #define SCCPMG_MESSAGE_TYPE_LENGTH 1
  80
  81 #define SCCPMG_AFFECTED_SSN_OFFSET SCCPMG_MESSAGE_TYPE_LENGTH
  82 #define SCCPMG_AFFECTED_SSN_LENGTH 1
  83
  84 #define SCCPMG_AFFECTED_PC_OFFSET (SCCPMG_AFFECTED_SSN_OFFSET + SCCPMG_AFFECTED_SSN_LENGTH)
  85 #define ITU_SCCPMG_AFFECTED_PC_LENGTH 2
  86 #define ANSI_SCCPMG_AFFECTED_PC_LENGTH 3
  87
  88 #define ITU_SCCPMG_SMI_OFFSET (SCCPMG_AFFECTED_PC_OFFSET + ITU_SCCPMG_AFFECTED_PC_LENGTH)
  89 #define ANSI_SCCPMG_SMI_OFFSET (SCCPMG_AFFECTED_PC_OFFSET + ANSI_SCCPMG_AFFECTED_PC_LENGTH)
  90 #define SCCPMG_SMI_LENGTH 1
  91 #define SCCPMG_SMI_MASK 0x3
  92
  93 #define ITU_SCCPMG_CONGESTION_OFFSET (ITU_SCCPMG_SMI_OFFSET + SCCPMG_SMI_LENGTH)
  94 #define ITU_SCCPMG_CONGESTION_LENGTH 1
  95 #define ITU_SCCPMG_CONGESTION_MASK 0x0f
  96
  97 #define SCCPMG_SSN_LENGTH    1
  98
  99 /* Initialize the protocol and registered fields */
 100 static int proto_sccpmg = -1;
 101 static int hf_sccpmg_message_type = -1;
 102 static int hf_sccpmg_affected_ssn = -1;
 103 static int hf_sccpmg_affected_pc = -1;
 104 static int hf_sccpmg_affected_pc_member = -1;
 105 static int hf_sccpmg_affected_pc_cluster = -1;
 106 static int hf_sccpmg_affected_pc_network = -1;
 107 static int hf_sccpmg_smi = -1;
 108 static int hf_sccpmg_congestion_level = -1;
 109
 110 /* Initialize the subtree pointers */
 111 static gint ett_sccpmg = -1;
 112 static gint ett_sccpmg_affected_pc = -1;
 113
 114 static void
 115 dissect_sccpmg_unknown_message(tvbuff_t *message_tvb, proto_tree *sccpmg_tree)
 116 {
 117         guint32 message_length;
 118
 119         message_length = tvb_length(message_tvb);
 120
 121         proto_tree_add_text(sccpmg_tree, message_tvb, 0, message_length,
 122                             "Unknown message (%u byte%s)", message_length,
 123                             plurality(message_length, "", "s"));
 124 }
 125
 126 static void
 127 dissect_sccpmg_affected_ssn(tvbuff_t *tvb, proto_tree *sccpmg_tree)
 128 {
 129         proto_tree_add_item(sccpmg_tree, hf_sccpmg_affected_ssn, tvb,
 130                             SCCPMG_AFFECTED_SSN_OFFSET, SCCPMG_SSN_LENGTH,
 131                             FALSE);
 132 }
 133
 134 static void
 135 dissect_sccpmg_affected_pc(tvbuff_t *tvb, proto_tree *sccpmg_tree)
 136 {
 137         proto_item *pc_item = 0;
 138         proto_tree *pc_tree = 0;
 139         guint32 dpc;
 140         guint8 offset = SCCPMG_AFFECTED_PC_OFFSET;
 141
 142         if (mtp3_standard == ITU_STANDARD) {
 143                 proto_tree_add_item(sccpmg_tree, hf_sccpmg_affected_pc, tvb,
 144                                     offset, ITU_PC_LENGTH, TRUE);
 145         } else if (mtp3_standard == ANSI_STANDARD) {
 146                 /* create the DPC tree; modified from that in packet-sccp.c */
 147                 dpc = tvb_get_ntoh24(tvb, offset);
 148                 pc_item = proto_tree_add_text(sccpmg_tree, tvb, offset,
 149                                               ANSI_PC_LENGTH, "PC (%d-%d-%d)",
 150                                               (dpc & ANSI_NETWORK_MASK),
 151                                               ((dpc & ANSI_CLUSTER_MASK) >> 8),
 152                                               ((dpc & ANSI_MEMBER_MASK) >> 16));
 153
 154                 pc_tree = proto_item_add_subtree(pc_item,
 155                                                  ett_sccpmg_affected_pc);
 156
 157                 proto_tree_add_uint(pc_tree, hf_sccpmg_affected_pc_member, tvb,
 158                                     offset, ANSI_NCM_LENGTH, dpc);
 159                 offset += ANSI_NCM_LENGTH;
 160                 proto_tree_add_uint(pc_tree, hf_sccpmg_affected_pc_cluster, tvb,
 161                                     offset, ANSI_NCM_LENGTH, dpc);
 162                 offset += ANSI_NCM_LENGTH;
 163                 proto_tree_add_uint(pc_tree, hf_sccpmg_affected_pc_network,
 164                                     tvb, offset, ANSI_NCM_LENGTH, dpc);
 165         }
 166 }
 167
 168 static void
 169 dissect_sccpmg_smi(tvbuff_t *tvb, proto_tree *sccpmg_tree)
 170 {
 171         guint8 offset = 0;
 172
 173         if (mtp3_standard == ITU_STANDARD)
 174                 offset = ITU_SCCPMG_SMI_OFFSET;
 175         else
 176                 offset = ANSI_SCCPMG_SMI_OFFSET;
 177
 178         proto_tree_add_item(sccpmg_tree, hf_sccpmg_smi, tvb, offset,
 179                             SCCPMG_SMI_LENGTH, FALSE);
 180 }
 181
 182 static void
 183 dissect_sccpmg_congestion_level(tvbuff_t *tvb, proto_tree *sccpmg_tree)
 184 {
 185         proto_tree_add_item(sccpmg_tree, hf_sccpmg_congestion_level, tvb,
 186                             ITU_SCCPMG_CONGESTION_OFFSET,
 187                             ITU_SCCPMG_CONGESTION_LENGTH, FALSE);
 188 }
 189
 190 static void
 191 dissect_sccpmg_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *sccpmg_tree)
 192 {
 193         guint8 message_type;
 194         guint8 offset = 0;
 195
 196         /* Extract the message type;  all other processing is based on this */
 197         message_type   = tvb_get_guint8(tvb, SCCPMG_MESSAGE_TYPE_OFFSET);
 198         offset = SCCPMG_MESSAGE_TYPE_LENGTH;
 199
 200         if (check_col(pinfo->cinfo, COL_INFO)) {
 201                 col_append_fstr(pinfo->cinfo, COL_INFO, "(%s) ",
 202                                 val_to_str(message_type,
 203                                            sccpmg_message_type_acro_values,
 204                                            "Unknown"));
 205         }
 206
 207         if (sccpmg_tree) {
 208                 /* add the message type to the protocol tree */
 209                 proto_tree_add_uint(sccpmg_tree, hf_sccpmg_message_type, tvb,
 210                                     SCCPMG_MESSAGE_TYPE_OFFSET,
 211                                     SCCPMG_MESSAGE_TYPE_LENGTH, message_type);
 212         }
 213
 214         switch(message_type) {
 215         case SCCPMG_MESSAGE_TYPE_SBR:
 216         case SCCPMG_MESSAGE_TYPE_SNR:
 217         case SCCPMG_MESSAGE_TYPE_SRT:
 218                 if (mtp3_standard == ITU_STANDARD)
 219                 {
 220                         dissect_sccpmg_unknown_message(tvb, sccpmg_tree);
 221                         break;
 222                 }
 223                 /* else fallthrough */
 224         case SCCPMG_MESSAGE_TYPE_SSA:
 225         case SCCPMG_MESSAGE_TYPE_SSP:
 226         case SCCPMG_MESSAGE_TYPE_SST:
 227         case SCCPMG_MESSAGE_TYPE_SOR:
 228         case SCCPMG_MESSAGE_TYPE_SOG:
 229                 dissect_sccpmg_affected_ssn(tvb, sccpmg_tree);
 230                 dissect_sccpmg_affected_pc(tvb, sccpmg_tree);
 231                 dissect_sccpmg_smi(tvb, sccpmg_tree);
 232
 233                 break;
 234         case SCCPMG_MESSAGE_TYPE_SSC:
 235                 if (mtp3_standard == ITU_STANDARD)
 236                 {
 237                         dissect_sccpmg_affected_ssn(tvb, sccpmg_tree);
 238                         dissect_sccpmg_affected_pc(tvb, sccpmg_tree);
 239                         dissect_sccpmg_smi(tvb, sccpmg_tree);
 240                         dissect_sccpmg_congestion_level(tvb, sccpmg_tree);
 241                 }
 242                 /* else fallthrough */
 243
 244         default:
 245                 dissect_sccpmg_unknown_message(tvb, sccpmg_tree);
 246         }
 247 }
 248
 249 static void
 250 dissect_sccpmg(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 251 {
 252         proto_item *sccpmg_item;
 253         proto_tree *sccpmg_tree = NULL;
 254
 255         /* Make entry in the Protocol column on summary display */
 256         if (check_col(pinfo->cinfo, COL_PROTOCOL))
 257                 col_set_str(pinfo->cinfo, COL_PROTOCOL, "SCCPMG");
 258
 259         /* In the interest of speed, if "tree" is NULL, don't do any work not
 260            necessary to generate protocol tree items. */
 261         if (tree) {
 262                 /* create the sccpmg protocol tree */
 263                 sccpmg_item = proto_tree_add_item(tree, proto_sccpmg, tvb, 0,
 264                                                   -1, FALSE);
 265                 sccpmg_tree = proto_item_add_subtree(sccpmg_item, ett_sccpmg);
 266         }
 267
 268         /* dissect the message */
 269         dissect_sccpmg_message(tvb, pinfo, sccpmg_tree);
 270 }
 271
 272 /* Register the protocol with Ethereal */
 273 void
 274 proto_register_sccpmg(void)
 275 {
 276         /* Setup list of header fields */
 277         static hf_register_info hf[] = {
 278           { &hf_sccpmg_message_type,
 279             { "Message Type", "sccpmg.message_type",
 280             FT_UINT8, BASE_HEX, VALS(sccpmg_message_type_values), 0x0,
 281             "", HFILL}},
 282           { &hf_sccpmg_affected_ssn,
 283             { "Affected SubSystem Number", "sccpmg.ssn",
 284             FT_UINT8, BASE_DEC, NULL, 0x0,
 285             "", HFILL}},
 286           { &hf_sccpmg_affected_pc,
 287             { "Affected Point Code", "sccpmg.pc",
 288             FT_UINT16, BASE_DEC, NULL, ITU_PC_MASK,
 289             "", HFILL}},
 290           { &hf_sccpmg_affected_pc_network,
 291             { "Affected PC Network",
 292             "sccpmg.network",
 293             FT_UINT24, BASE_DEC, NULL, ANSI_NETWORK_MASK,
 294             "", HFILL}},
 295           { &hf_sccpmg_affected_pc_cluster,
 296             { "Affected PC Cluster",
 297             "sccpmg.cluster",
 298             FT_UINT24, BASE_DEC, NULL, ANSI_CLUSTER_MASK,
 299             "", HFILL}},
 300           { &hf_sccpmg_affected_pc_member,
 301             { "Affected PC Member",
 302             "sccpmg.member",
 303             FT_UINT24, BASE_DEC, NULL, ANSI_MEMBER_MASK,
 304             "", HFILL}},
 305           { &hf_sccpmg_smi,
 306             { "Subsystem Multiplicity Indicator",
 307             "sccpmg.smi",
 308             FT_UINT8, BASE_DEC, NULL, SCCPMG_SMI_MASK,
 309             "", HFILL}},
 310           { &hf_sccpmg_congestion_level,
 311             { "SCCP Congestionl Level (ITU)",
 312             "sccpmg.congestion",
 313             FT_UINT8, BASE_DEC, NULL, ITU_SCCPMG_CONGESTION_MASK,
 314             "", HFILL}}
 315         };
 316
 317         /* Setup protocol subtree array */
 318         static gint *ett[] = {
 319                 &ett_sccpmg,
 320                 &ett_sccpmg_affected_pc
 321         };
 322
 323         /* Register the protocol name and description */
 324         proto_sccpmg = proto_register_protocol("Signalling Connection Control Part Management",
 325                                                "SCCPMG", "sccpmg");
 326
 327         /* Required function calls to register the header fields and subtrees
 328            used */
 329         proto_register_field_array(proto_sccpmg, hf, array_length(hf));
 330         proto_register_subtree_array(ett, array_length(ett));
 331 }
 332
 333 void
 334 proto_reg_handoff_sccpmg(void)
 335 {
 336         dissector_handle_t sccpmg_handle;
 337
 338         sccpmg_handle = create_dissector_handle(dissect_sccpmg, proto_sccpmg);
 339
 340         /* Register for SCCP SSN=1 messages */
 341         dissector_add("sccp.ssn", SCCPMG_SSN, sccpmg_handle);
 342 }
 343