packet-frame.c

   1 /* packet-frame.c
   2  *
   3  * Top-most dissector. Decides dissector based on Wiretap Encapsulation Type.
   4  *
   5  * $Id: packet-frame.c,v 1.14 2001/12/08 21:03:41 guy Exp $
   6  *
   7  * Ethereal - Network traffic analyzer
   8  * By Gerald Combs <gerald@ethereal.com>
   9  * Copyright 2000 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 "packet.h"
  32 #include "timestamp.h"
  33 #include "tvbuff.h"
  34 #include "packet-frame.h"
  35 #include "prefs.h"
  36
  37 static int proto_frame = -1;
  38 static int hf_frame_arrival_time = -1;
  39 static int hf_frame_time_delta = -1;
  40 static int hf_frame_time_relative = -1;
  41 static int hf_frame_number = -1;
  42 static int hf_frame_packet_len = -1;
  43 static int hf_frame_capture_len = -1;
  44 static int hf_frame_p2p_dir = -1;
  45 static int hf_frame_file_off = -1;
  46 static int proto_short = -1;
  47 int proto_malformed = -1;
  48
  49 static gint ett_frame = -1;
  50
  51 static dissector_handle_t data_handle;
  52
  53 /* Preferences */
  54 static gboolean show_file_off = FALSE;
  55
  56 static const value_string p2p_dirs[] = {
  57         { P2P_DIR_SENT, "Sent" },
  58         { P2P_DIR_RECV, "Received" },
  59         { 0, NULL }
  60 };
  61
  62 static dissector_table_t wtap_encap_dissector_table;
  63
  64 void
  65 dissect_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  66 {
  67         proto_tree      *fh_tree;
  68         proto_item      *ti;
  69         nstime_t        ts;
  70         int             cap_len, pkt_len;
  71
  72         pinfo->current_proto = "Frame";
  73
  74         if (pinfo->fd->lnk_t == WTAP_ENCAP_LAPD ||
  75                         pinfo->fd->lnk_t == WTAP_ENCAP_PPP_WITH_PHDR) {
  76
  77                 pinfo->p2p_dir = pinfo->pseudo_header->p2p.sent ? P2P_DIR_SENT : P2P_DIR_RECV;
  78         }
  79
  80         /* Put in frame header information. */
  81         if (tree) {
  82
  83           cap_len = tvb_length(tvb);
  84           pkt_len = tvb_reported_length(tvb);
  85
  86           ti = proto_tree_add_protocol_format(tree, proto_frame, tvb, 0, tvb_length(tvb),
  87             "Frame %u (%u on wire, %u captured)", pinfo->fd->num, pkt_len, cap_len);
  88
  89           fh_tree = proto_item_add_subtree(ti, ett_frame);
  90
  91           ts.secs = pinfo->fd->abs_secs;
  92           ts.nsecs = pinfo->fd->abs_usecs*1000;
  93
  94           proto_tree_add_time(fh_tree, hf_frame_arrival_time, tvb,
  95                 0, 0, &ts);
  96
  97           ts.secs = pinfo->fd->del_secs;
  98           ts.nsecs = pinfo->fd->del_usecs*1000;
  99
 100           proto_tree_add_time(fh_tree, hf_frame_time_delta, tvb,
 101                 0, 0, &ts);
 102
 103           ts.secs = pinfo->fd->rel_secs;
 104           ts.nsecs = pinfo->fd->rel_usecs*1000;
 105
 106           proto_tree_add_time(fh_tree, hf_frame_time_relative, tvb,
 107                 0, 0, &ts);
 108
 109           proto_tree_add_uint(fh_tree, hf_frame_number, tvb,
 110                 0, 0, pinfo->fd->num);
 111
 112           proto_tree_add_uint_format(fh_tree, hf_frame_packet_len, tvb,
 113                 0, 0, pkt_len, "Packet Length: %d byte%s", pkt_len,
 114                 plurality(pkt_len, "", "s"));
 115
 116           proto_tree_add_uint_format(fh_tree, hf_frame_capture_len, tvb,
 117                 0, 0, cap_len, "Capture Length: %d byte%s", cap_len,
 118                 plurality(cap_len, "", "s"));
 119
 120           /* Check for existences of P2P pseudo header */
 121           if (pinfo->p2p_dir != P2P_DIR_UNKNOWN) {
 122                   proto_tree_add_uint(fh_tree, hf_frame_p2p_dir, tvb,
 123                                   0, 0, pinfo->p2p_dir);
 124           }
 125
 126           if (show_file_off) {
 127                   proto_tree_add_int_format(fh_tree, hf_frame_file_off, tvb,
 128                                   0, 0, pinfo->fd->file_off,
 129                                   "File Offset: %ld (0x%lx)",
 130                                   pinfo->fd->file_off, pinfo->fd->file_off);
 131           }
 132         }
 133
 134
 135         TRY {
 136                 if (!dissector_try_port(wtap_encap_dissector_table, pinfo->fd->lnk_t,
 137                                         tvb, pinfo, tree)) {
 138
 139                         if (check_col(pinfo->fd, COL_PROTOCOL))
 140                                 col_set_str(pinfo->fd, COL_PROTOCOL, "UNKNOWN");
 141                         if (check_col(pinfo->fd, COL_INFO))
 142                                 col_add_fstr(pinfo->fd, COL_INFO, "WTAP_ENCAP = %u", pinfo->fd->lnk_t);
 143                         call_dissector(data_handle,tvb, pinfo, tree);
 144                 }
 145         }
 146         CATCH(BoundsError) {
 147                 if (check_col(pinfo->fd, COL_INFO))
 148                         col_append_str(pinfo->fd, COL_INFO, "[Short Frame]");
 149                 proto_tree_add_protocol_format(tree, proto_short, tvb, 0, 0,
 150                                 "[Short Frame: %s]", pinfo->current_proto );
 151         }
 152         CATCH(ReportedBoundsError) {
 153                 if (check_col(pinfo->fd, COL_INFO))
 154                         col_append_str(pinfo->fd, COL_INFO, "[Malformed Frame]");
 155                 proto_tree_add_protocol_format(tree, proto_malformed, tvb, 0, 0,
 156                                 "[Malformed Frame: %s]", pinfo->current_proto );
 157         }
 158         ENDTRY;
 159 }
 160
 161 void
 162 proto_register_frame(void)
 163 {
 164         static hf_register_info hf[] = {
 165                 { &hf_frame_arrival_time,
 166                 { "Arrival Time",               "frame.time", FT_ABSOLUTE_TIME, BASE_NONE, NULL, 0x0,
 167                         "", HFILL }},
 168
 169                 { &hf_frame_time_delta,
 170                 { "Time delta from previous packet",    "frame.time_delta", FT_RELATIVE_TIME, BASE_NONE, NULL,
 171                         0x0,
 172                         "", HFILL }},
 173
 174                 { &hf_frame_time_relative,
 175                 { "Time relative to first packet",      "frame.time_relative", FT_RELATIVE_TIME, BASE_NONE, NULL,
 176                         0x0,
 177                         "", HFILL }},
 178
 179                 { &hf_frame_number,
 180                 { "Frame Number",               "frame.number", FT_UINT32, BASE_DEC, NULL, 0x0,
 181                         "", HFILL }},
 182
 183                 { &hf_frame_packet_len,
 184                 { "Total Frame Length",         "frame.pkt_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 185                         "", HFILL }},
 186
 187                 { &hf_frame_capture_len,
 188                 { "Capture Frame Length",       "frame.cap_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 189                         "", HFILL }},
 190
 191                 { &hf_frame_p2p_dir,
 192                 { "Point-to-Point Direction",   "frame.p2p_dir", FT_UINT8, BASE_DEC, VALS(p2p_dirs), 0x0,
 193                         "", HFILL }},
 194
 195                 { &hf_frame_file_off,
 196                 { "File Offset",        "frame.file_off", FT_INT32, BASE_DEC, NULL, 0x0,
 197                         "", HFILL }},
 198
 199         };
 200         static gint *ett[] = {
 201                 &ett_frame,
 202         };
 203         module_t *frame_module;
 204
 205         wtap_encap_dissector_table = register_dissector_table("wtap_encap",
 206             "Wiretap encapsulation type", FT_UINT32, BASE_DEC);
 207
 208         proto_frame = proto_register_protocol("Frame", "Frame", "frame");
 209         proto_register_field_array(proto_frame, hf, array_length(hf));
 210         proto_register_subtree_array(ett, array_length(ett));
 211         register_dissector("frame",dissect_frame,proto_frame);
 212
 213         /* You can't disable dissection of "Frame", as that would be
 214            tantamount to not doing any dissection whatsoever. */
 215         proto_set_cant_disable(proto_frame);
 216
 217         proto_short = proto_register_protocol("Short Frame", "Short frame", "short");
 218         proto_malformed = proto_register_protocol("Malformed Frame",
 219             "Malformed frame", "malformed");
 220
 221         /* "Short Frame" and "Malformed Frame" aren't really protocols,
 222            they're error indications; disabling them makes no sense. */
 223         proto_set_cant_disable(proto_short);
 224         proto_set_cant_disable(proto_malformed);
 225
 226         /* Our preferences */
 227         frame_module = prefs_register_protocol(proto_frame, NULL);
 228         prefs_register_bool_preference(frame_module, "show_file_off",
 229             "Show File Offset", "Show File Offset", &show_file_off);
 230 }
 231
 232 void
 233 proto_reg_handoff_frame(void)
 234 {
 235         data_handle = find_dissector("data");
 236 }