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 1.12 2001/12/06 22:52:18 guy Exp $
   6  *
   7  * Ethereal - Network traffic analyzer
   8  * By Gerald Combs <gerald@zing.org>
   9  * Copyright 2000 Gerald Combs
  10  *
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  25  */
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <glib.h>
  32 #include "packet.h"
  33 #include "timestamp.h"
  34 #include "tvbuff.h"
  35 #include "packet-frame.h"
  36 #include "prefs.h"
  37
  38 static int proto_frame = -1;
  39 static int hf_frame_arrival_time = -1;
  40 static int hf_frame_time_delta = -1;
  41 static int hf_frame_time_relative = -1;
  42 static int hf_frame_number = -1;
  43 static int hf_frame_packet_len = -1;
  44 static int hf_frame_capture_len = -1;
  45 static int hf_frame_p2p_dir = -1;
  46 static int hf_frame_file_off = -1;
  47 static int proto_short = -1;
  48 int proto_malformed = -1;
  49
  50 static gint ett_frame = -1;
  51
  52 static dissector_handle_t data_handle;
  53
  54 /* Preferences */
  55 static gboolean show_file_off = FALSE;
  56
  57 static const value_string p2p_dirs[] = {
  58         { P2P_DIR_SENT, "Sent" },
  59         { P2P_DIR_RECV, "Received" },
  60         { 0, NULL }
  61 };
  62
  63 static dissector_table_t wtap_encap_dissector_table;
  64
  65 void
  66 dissect_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  67 {
  68         proto_tree      *fh_tree;
  69         proto_item      *ti;
  70         nstime_t        ts;
  71         int             cap_len, pkt_len;
  72
  73         pinfo->current_proto = "Frame";
  74
  75         if (pinfo->fd->lnk_t == WTAP_ENCAP_LAPD ||
  76                         pinfo->fd->lnk_t == WTAP_ENCAP_PPP_WITH_PHDR) {
  77
  78                 pinfo->p2p_dir = pinfo->pseudo_header->p2p.sent ? P2P_DIR_SENT : P2P_DIR_RECV;
  79         }
  80
  81         /* Put in frame header information. */
  82         if (tree) {
  83
  84           cap_len = tvb_length(tvb);
  85           pkt_len = tvb_reported_length(tvb);
  86
  87           ti = proto_tree_add_protocol_format(tree, proto_frame, tvb, 0, tvb_length(tvb),
  88             "Frame %u (%u on wire, %u captured)", pinfo->fd->num, pkt_len, cap_len);
  89
  90           fh_tree = proto_item_add_subtree(ti, ett_frame);
  91
  92           ts.secs = pinfo->fd->abs_secs;
  93           ts.nsecs = pinfo->fd->abs_usecs*1000;
  94
  95           proto_tree_add_time(fh_tree, hf_frame_arrival_time, tvb,
  96                 0, 0, &ts);
  97
  98           ts.secs = pinfo->fd->del_secs;
  99           ts.nsecs = pinfo->fd->del_usecs*1000;
 100
 101           proto_tree_add_time(fh_tree, hf_frame_time_delta, tvb,
 102                 0, 0, &ts);
 103
 104           ts.secs = pinfo->fd->rel_secs;
 105           ts.nsecs = pinfo->fd->rel_usecs*1000;
 106
 107           proto_tree_add_time(fh_tree, hf_frame_time_relative, tvb,
 108                 0, 0, &ts);
 109
 110           proto_tree_add_uint(fh_tree, hf_frame_number, tvb,
 111                 0, 0, pinfo->fd->num);
 112
 113           proto_tree_add_uint_format(fh_tree, hf_frame_packet_len, tvb,
 114                 0, 0, pkt_len, "Packet Length: %d byte%s", pkt_len,
 115                 plurality(pkt_len, "", "s"));
 116
 117           proto_tree_add_uint_format(fh_tree, hf_frame_capture_len, tvb,
 118                 0, 0, cap_len, "Capture Length: %d byte%s", cap_len,
 119                 plurality(cap_len, "", "s"));
 120
 121           /* Check for existences of P2P pseudo header */
 122           if (pinfo->p2p_dir != P2P_DIR_UNKNOWN) {
 123                   proto_tree_add_uint(fh_tree, hf_frame_p2p_dir, tvb,
 124                                   0, 0, pinfo->p2p_dir);
 125           }
 126
 127       if (show_file_off) {
 128         proto_tree_add_int_format(fh_tree, hf_frame_file_off, tvb,
 129             0, 0, pinfo->fd->file_off, "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
 207         proto_frame = proto_register_protocol("Frame", "Frame", "frame");
 208         proto_register_field_array(proto_frame, hf, array_length(hf));
 209         proto_register_subtree_array(ett, array_length(ett));
 210         register_dissector("frame",dissect_frame,proto_frame);
 211
 212         /* You can't disable dissection of "Frame", as that would be
 213            tantamount to not doing any dissection whatsoever. */
 214         proto_set_cant_disable(proto_frame);
 215
 216         proto_short = proto_register_protocol("Short Frame", "Short frame", "short");
 217         proto_malformed = proto_register_protocol("Malformed Frame",
 218             "Malformed frame", "malformed");
 219
 220         /* "Short Frame" and "Malformed Frame" aren't really protocols,
 221            they're error indications; disabling them makes no sense. */
 222         proto_set_cant_disable(proto_short);
 223         proto_set_cant_disable(proto_malformed);
 224
 225     /* Our preferences */
 226     frame_module = prefs_register_protocol(proto_frame, NULL);
 227     prefs_register_bool_preference(frame_module, "show_file_off",
 228         "Show File Offset", "Show File Offset", &show_file_off);
 229 }
 230
 231 void
 232 proto_reg_handoff_frame(void){
 233   data_handle = find_dissector("data");
 234 }