asn1/rtse/packet-rtse-template.c

   1 /* packet-rtse_asn1.c
   2  * Routines for RTSE packet dissection
   3  * Graeme Lunt 2005
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  24  */
  25
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include <glib.h>
  31 #include <epan/packet.h>
  32 #include <epan/conversation.h>
  33 #include <epan/prefs.h>
  34 #include <epan/reassemble.h>
  35 #include <epan/asn1.h>
  36 #include <epan/expert.h>
  37
  38 #include "packet-ber.h"
  39 #include "packet-pres.h"
  40 #include "packet-acse.h"
  41 #include "packet-ros.h"
  42 #include "packet-rtse.h"
  43
  44 #define PNAME  "X.228 OSI Reliable Transfer Service"
  45 #define PSNAME "RTSE"
  46 #define PFNAME "rtse"
  47
  48 /* Initialize the protocol and registered fields */
  49 static int proto_rtse = -1;
  50
  51 static struct SESSION_DATA_STRUCTURE* session = NULL;
  52
  53 static gboolean open_request=FALSE;
  54 static guint32 app_proto=0;
  55
  56 static proto_tree *top_tree=NULL;
  57
  58 /* Preferences */
  59 static gboolean rtse_reassemble = TRUE;
  60
  61 #include "packet-rtse-hf.c"
  62
  63 /* Initialize the subtree pointers */
  64 static gint ett_rtse = -1;
  65 #include "packet-rtse-ett.c"
  66
  67
  68 static dissector_table_t rtse_oid_dissector_table=NULL;
  69 static GHashTable *oid_table=NULL;
  70 static gint ett_rtse_unknown = -1;
  71
  72 static GHashTable *rtse_segment_table = NULL;
  73 static GHashTable *rtse_reassembled_table = NULL;
  74
  75 static int hf_rtse_segment_data = -1;
  76 static int hf_rtse_fragments = -1;
  77 static int hf_rtse_fragment = -1;
  78 static int hf_rtse_fragment_overlap = -1;
  79 static int hf_rtse_fragment_overlap_conflicts = -1;
  80 static int hf_rtse_fragment_multiple_tails = -1;
  81 static int hf_rtse_fragment_too_long_fragment = -1;
  82 static int hf_rtse_fragment_error = -1;
  83 static int hf_rtse_fragment_count = -1;
  84 static int hf_rtse_reassembled_in = -1;
  85 static int hf_rtse_reassembled_length = -1;
  86
  87 static gint ett_rtse_fragment = -1;
  88 static gint ett_rtse_fragments = -1;
  89
  90 static const fragment_items rtse_frag_items = {
  91         /* Fragment subtrees */
  92         &ett_rtse_fragment,
  93         &ett_rtse_fragments,
  94         /* Fragment fields */
  95         &hf_rtse_fragments,
  96         &hf_rtse_fragment,
  97         &hf_rtse_fragment_overlap,
  98         &hf_rtse_fragment_overlap_conflicts,
  99         &hf_rtse_fragment_multiple_tails,
 100         &hf_rtse_fragment_too_long_fragment,
 101         &hf_rtse_fragment_error,
 102         &hf_rtse_fragment_count,
 103         /* Reassembled in field */
 104         &hf_rtse_reassembled_in,
 105         /* Reassembled length field */
 106         &hf_rtse_reassembled_length,
 107         /* Tag */
 108         "RTSE fragments"
 109 };
 110
 111 void
 112 register_rtse_oid_dissector_handle(const char *oid, dissector_handle_t dissector, int proto, const char *name, gboolean uses_ros)
 113 {
 114 /* XXX: Note that this fcn is called from proto_reg_handoff in *other* dissectors ... */
 115
 116   static  dissector_handle_t rtse_handle = NULL;
 117   static  dissector_handle_t ros_handle = NULL;
 118
 119   if (rtse_handle == NULL)
 120     rtse_handle = find_dissector("rtse");
 121   if (ros_handle == NULL)
 122     ros_handle = find_dissector("ros");
 123
 124   /* save the name - but not used */
 125   g_hash_table_insert(oid_table, (gpointer)oid, (gpointer)name);
 126
 127   /* register RTSE with the BER (ACSE) */
 128   register_ber_oid_dissector_handle(oid, rtse_handle, proto, name);
 129
 130   if(uses_ros) {
 131     /* make sure we call ROS ... */
 132     dissector_add_string("rtse.oid", oid, ros_handle);
 133
 134     /* and then tell ROS how to dissect the AS*/
 135     register_ros_oid_dissector_handle(oid, dissector, proto, name, TRUE);
 136
 137   } else {
 138     /* otherwise we just remember how to dissect the AS */
 139     dissector_add_string("rtse.oid", oid, dissector);
 140   }
 141 }
 142
 143 static int
 144 call_rtse_oid_callback(const char *oid, tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree)
 145 {
 146         tvbuff_t *next_tvb;
 147
 148         next_tvb = tvb_new_subset(tvb, offset, tvb_length_remaining(tvb, offset), tvb_reported_length_remaining(tvb, offset));
 149         if(!dissector_try_string(rtse_oid_dissector_table, oid, next_tvb, pinfo, tree)){
 150                 proto_item *item=proto_tree_add_text(tree, next_tvb, 0, tvb_length_remaining(tvb, offset), "RTSE: Dissector for OID:%s not implemented. Contact Wireshark developers if you want this supported", oid);
 151                 proto_tree *next_tree=proto_item_add_subtree(item, ett_rtse_unknown);
 152
 153                 expert_add_info_format (pinfo, item, PI_UNDECODED, PI_WARN,
 154                                         "RTSE: Dissector for OID %s not implemented", oid);
 155                 dissect_unknown_ber(pinfo, next_tvb, offset, next_tree);
 156         }
 157
 158         /*XXX until we change the #.REGISTER signature for _PDU()s
 159          * into new_dissector_t   we have to do this kludge with
 160          * manually step past the content in the ANY type.
 161          */
 162         offset+=tvb_length_remaining(tvb, offset);
 163
 164         return offset;
 165 }
 166
 167 static int
 168 call_rtse_external_type_callback(gboolean implicit_tag _U_, tvbuff_t *tvb, int offset, asn1_ctx_t *actx, proto_tree *tree, int hf_index _U_)
 169 {
 170         const char      *oid = NULL;
 171
 172         if (actx->external.indirect_ref_present) {
 173                 oid = (const char *)find_oid_by_pres_ctx_id(actx->pinfo, actx->external.indirect_reference);
 174         } else if (actx->external.direct_ref_present) {
 175                 oid = actx->external.direct_reference;
 176         }
 177
 178         if (oid)
 179                 offset = call_rtse_oid_callback(oid, tvb, offset, actx->pinfo, top_tree ? top_tree : tree);
 180
 181         return offset;
 182 }
 183
 184 #include "packet-rtse-fn.c"
 185
 186 /*
 187 * Dissect RTSE PDUs inside a PPDU.
 188 */
 189 static void
 190 dissect_rtse(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree)
 191 {
 192         int offset = 0;
 193         int old_offset;
 194         proto_item *item=NULL;
 195         proto_tree *tree=NULL;
 196         proto_tree *next_tree=NULL;
 197         tvbuff_t *next_tvb = NULL;
 198         tvbuff_t *data_tvb = NULL;
 199         fragment_data *frag_msg = NULL;
 200         guint32 fragment_length;
 201         guint32 rtse_id = 0;
 202         gboolean data_handled = FALSE;
 203         conversation_t *conversation = NULL;
 204         asn1_ctx_t asn1_ctx;
 205         asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo);
 206
 207         /* save parent_tree so subdissectors can create new top nodes */
 208         top_tree=parent_tree;
 209
 210         /* do we have application context from the acse dissector?  */
 211         if( !pinfo->private_data ){
 212                 if(parent_tree){
 213                         proto_tree_add_text(parent_tree, tvb, offset, -1,
 214                                 "Internal error:can't get application context from ACSE dissector.");
 215                 }
 216                 return  ;
 217         } else {
 218                 session  = ( (struct SESSION_DATA_STRUCTURE*)(pinfo->private_data) );
 219
 220         }
 221
 222         col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTSE");
 223         col_clear(pinfo->cinfo, COL_INFO);
 224
 225         if (rtse_reassemble &&
 226             ((session->spdu_type == SES_DATA_TRANSFER) ||
 227              (session->spdu_type == SES_MAJOR_SYNC_POINT))) {
 228                 /* Use conversation index as fragment id */
 229                 conversation  = find_conversation (pinfo->fd->num,
 230                                                    &pinfo->src, &pinfo->dst, pinfo->ptype,
 231                                                    pinfo->srcport, pinfo->destport, 0);
 232                 if (conversation != NULL) {
 233                         rtse_id = conversation->index;
 234                 }
 235                 session->rtse_reassemble = TRUE;
 236         }
 237         if (rtse_reassemble && session->spdu_type == SES_MAJOR_SYNC_POINT) {
 238                 frag_msg = fragment_end_seq_next (pinfo, rtse_id, rtse_segment_table,
 239                                                   rtse_reassembled_table);
 240                 next_tvb = process_reassembled_data (tvb, offset, pinfo, "Reassembled RTSE",
 241                                                      frag_msg, &rtse_frag_items, NULL, parent_tree);
 242         }
 243         if(parent_tree){
 244                 item = proto_tree_add_item(parent_tree, proto_rtse, next_tvb ? next_tvb : tvb, 0, -1, ENC_NA);
 245                 tree = proto_item_add_subtree(item, ett_rtse);
 246         }
 247         if (rtse_reassemble && session->spdu_type == SES_DATA_TRANSFER) {
 248                 /* strip off the OCTET STRING encoding - including any CONSTRUCTED OCTET STRING */
 249                 dissect_ber_octet_string(FALSE, &asn1_ctx, tree, tvb, offset, hf_rtse_segment_data, &data_tvb);
 250
 251                 if (data_tvb) {
 252                         fragment_length = tvb_length_remaining (data_tvb, 0);
 253                         proto_item_append_text(asn1_ctx.created_item, " (%u byte%s)", fragment_length,
 254                                       plurality(fragment_length, "", "s"));
 255                         frag_msg = fragment_add_seq_next (data_tvb, 0, pinfo,
 256                                                           rtse_id, rtse_segment_table,
 257                                                           rtse_reassembled_table, fragment_length, TRUE);
 258                         if (frag_msg && pinfo->fd->num != frag_msg->reassembled_in) {
 259                                 /* Add a "Reassembled in" link if not reassembled in this frame */
 260                                 proto_tree_add_uint (tree, *(rtse_frag_items.hf_reassembled_in),
 261                                                      data_tvb, 0, 0, frag_msg->reassembled_in);
 262                         }
 263                         pinfo->fragmented = TRUE;
 264                         data_handled = TRUE;
 265                 } else {
 266                         fragment_length = tvb_length_remaining (tvb, offset);
 267                 }
 268
 269                 if (check_col(pinfo->cinfo, COL_INFO))
 270                         col_append_fstr(pinfo->cinfo, COL_INFO, "[RTSE fragment, %u byte%s]",
 271                                         fragment_length, plurality(fragment_length, "", "s"));
 272         } else if (rtse_reassemble && session->spdu_type == SES_MAJOR_SYNC_POINT) {
 273                 if (next_tvb) {
 274                         /* ROS won't do this for us */
 275                         session->ros_op = (ROS_OP_INVOKE | ROS_OP_ARGUMENT);
 276                         offset=dissect_ber_external_type(FALSE, tree, next_tvb, 0, &asn1_ctx, -1, call_rtse_external_type_callback);
 277                 } else {
 278                         offset = tvb_length (tvb);
 279                 }
 280                 pinfo->fragmented = FALSE;
 281                 data_handled = TRUE;
 282         }
 283
 284         if (!data_handled) {
 285                 while (tvb_reported_length_remaining(tvb, offset) > 0){
 286                         old_offset=offset;
 287                         offset=dissect_rtse_RTSE_apdus(TRUE, tvb, offset, &asn1_ctx, tree, -1);
 288                         if(offset == old_offset){
 289                                 item = proto_tree_add_text(tree, tvb, offset, -1, "Unknown RTSE PDU");
 290
 291                                 if(item){
 292                                         expert_add_info_format (pinfo, item, PI_UNDECODED, PI_WARN, "Unknown RTSE PDU");
 293                                         next_tree=proto_item_add_subtree(item, ett_rtse_unknown);
 294                                         dissect_unknown_ber(pinfo, tvb, offset, next_tree);
 295                                 }
 296
 297                                 break;
 298                         }
 299                 }
 300         }
 301
 302         top_tree = NULL;
 303 }
 304
 305 static void rtse_reassemble_init (void)
 306 {
 307         fragment_table_init (&rtse_segment_table);
 308         reassembled_table_init (&rtse_reassembled_table);
 309 }
 310
 311 /*--- proto_register_rtse -------------------------------------------*/
 312 void proto_register_rtse(void) {
 313
 314   /* List of fields */
 315   static hf_register_info hf[] =
 316   {
 317     /* Fragment entries */
 318     { &hf_rtse_segment_data,
 319       { "RTSE segment data", "rtse.segment", FT_NONE, BASE_NONE,
 320         NULL, 0x00, NULL, HFILL } },
 321     { &hf_rtse_fragments,
 322       { "RTSE fragments", "rtse.fragments", FT_NONE, BASE_NONE,
 323         NULL, 0x00, NULL, HFILL } },
 324     { &hf_rtse_fragment,
 325       { "RTSE fragment", "rtse.fragment", FT_FRAMENUM, BASE_NONE,
 326         NULL, 0x00, NULL, HFILL } },
 327     { &hf_rtse_fragment_overlap,
 328       { "RTSE fragment overlap", "rtse.fragment.overlap", FT_BOOLEAN,
 329         BASE_NONE, NULL, 0x0, NULL, HFILL } },
 330     { &hf_rtse_fragment_overlap_conflicts,
 331       { "RTSE fragment overlapping with conflicting data",
 332         "rtse.fragment.overlap.conflicts", FT_BOOLEAN, BASE_NONE,
 333         NULL, 0x0, NULL, HFILL } },
 334     { &hf_rtse_fragment_multiple_tails,
 335       { "RTSE has multiple tail fragments",
 336         "rtse.fragment.multiple_tails", FT_BOOLEAN, BASE_NONE,
 337         NULL, 0x0, NULL, HFILL } },
 338     { &hf_rtse_fragment_too_long_fragment,
 339       { "RTSE fragment too long", "rtse.fragment.too_long_fragment",
 340         FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } },
 341     { &hf_rtse_fragment_error,
 342       { "RTSE defragmentation error", "rtse.fragment.error", FT_FRAMENUM,
 343         BASE_NONE, NULL, 0x00, NULL, HFILL } },
 344     { &hf_rtse_fragment_count,
 345       { "RTSE fragment count", "rtse.fragment.count", FT_UINT32, BASE_DEC,
 346         NULL, 0x00, NULL, HFILL } },
 347     { &hf_rtse_reassembled_in,
 348       { "Reassembled RTSE in frame", "rtse.reassembled.in", FT_FRAMENUM, BASE_NONE,
 349         NULL, 0x00, "This RTSE packet is reassembled in this frame", HFILL } },
 350     { &hf_rtse_reassembled_length,
 351       { "Reassembled RTSE length", "rtse.reassembled.length", FT_UINT32, BASE_DEC,
 352         NULL, 0x00, "The total length of the reassembled payload", HFILL } },
 353
 354 #include "packet-rtse-hfarr.c"
 355   };
 356
 357   /* List of subtrees */
 358   static gint *ett[] = {
 359     &ett_rtse,
 360     &ett_rtse_unknown,
 361     &ett_rtse_fragment,
 362     &ett_rtse_fragments,
 363 #include "packet-rtse-ettarr.c"
 364   };
 365
 366   module_t *rtse_module;
 367
 368   /* Register protocol */
 369   proto_rtse = proto_register_protocol(PNAME, PSNAME, PFNAME);
 370   register_dissector("rtse", dissect_rtse, proto_rtse);
 371   /* Register fields and subtrees */
 372   proto_register_field_array(proto_rtse, hf, array_length(hf));
 373   proto_register_subtree_array(ett, array_length(ett));
 374   register_init_routine (&rtse_reassemble_init);
 375   rtse_module = prefs_register_protocol_subtree("OSI", proto_rtse, NULL);
 376
 377   prefs_register_bool_preference(rtse_module, "reassemble",
 378                                  "Reassemble segmented RTSE datagrams",
 379                                  "Whether segmented RTSE datagrams should be reassembled."
 380                                  " To use this option, you must also enable"
 381                                  " \"Allow subdissectors to reassemble TCP streams\""
 382                                  " in the TCP protocol settings.", &rtse_reassemble);
 383
 384   rtse_oid_dissector_table = register_dissector_table("rtse.oid", "RTSE OID Dissectors", FT_STRING, BASE_NONE);
 385   oid_table=g_hash_table_new(g_str_hash, g_str_equal);
 386
 387
 388 }
 389
 390
 391 /*--- proto_reg_handoff_rtse --- */
 392 void proto_reg_handoff_rtse(void) {
 393
 394
 395 }