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 1.6 2001/01/03 06:55:28 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
  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 proto_short = -1;
  46 int proto_malformed = -1;
  47
  48 static gint ett_frame = -1;
  49
  50 static const value_string p2p_dirs[] = {
  51         { P2P_DIR_SENT, "Sent" },
  52         { P2P_DIR_RECV, "Received" },
  53         { 0, NULL }
  54 };
  55
  56 static dissector_table_t wtap_encap_dissector_table;
  57
  58 void
  59 dissect_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  60 {
  61         proto_tree      *fh_tree;
  62         proto_item      *ti;
  63         struct timeval  tv;
  64         int             cap_len, pkt_len;
  65
  66         pinfo->current_proto = "Frame";
  67
  68         if (pinfo->fd->lnk_t == WTAP_ENCAP_LAPD ||
  69                         pinfo->fd->lnk_t == WTAP_ENCAP_PPP_WITH_PHDR) {
  70
  71                 pinfo->p2p_dir = pinfo->pseudo_header->p2p.sent ? P2P_DIR_SENT : P2P_DIR_RECV;
  72         }
  73
  74         /* Put in frame header information. */
  75         if (tree) {
  76
  77           cap_len = tvb_length(tvb);
  78           pkt_len = tvb_reported_length(tvb);
  79
  80           ti = proto_tree_add_protocol_format(tree, proto_frame, tvb, 0, tvb_length(tvb),
  81             "Frame %u (%u on wire, %u captured)", pinfo->fd->num, pkt_len, cap_len);
  82
  83           fh_tree = proto_item_add_subtree(ti, ett_frame);
  84
  85           tv.tv_sec = pinfo->fd->abs_secs;
  86           tv.tv_usec = pinfo->fd->abs_usecs;
  87
  88           proto_tree_add_time(fh_tree, hf_frame_arrival_time, tvb,
  89                 0, 0, &tv);
  90
  91           tv.tv_sec = pinfo->fd->del_secs;
  92           tv.tv_usec = pinfo->fd->del_usecs;
  93
  94           proto_tree_add_time(fh_tree, hf_frame_time_delta, tvb,
  95                 0, 0, &tv);
  96
  97           tv.tv_sec = pinfo->fd->rel_secs;
  98           tv.tv_usec = pinfo->fd->rel_usecs;
  99
 100           proto_tree_add_time(fh_tree, hf_frame_time_relative, tvb,
 101                 0, 0, &tv);
 102
 103           proto_tree_add_uint(fh_tree, hf_frame_number, tvb,
 104                 0, 0, pinfo->fd->num);
 105
 106           proto_tree_add_uint_format(fh_tree, hf_frame_packet_len, tvb,
 107                 0, 0, pkt_len, "Packet Length: %d byte%s", pkt_len,
 108                 plurality(pkt_len, "", "s"));
 109
 110           proto_tree_add_uint_format(fh_tree, hf_frame_capture_len, tvb,
 111                 0, 0, cap_len, "Capture Length: %d byte%s", cap_len,
 112                 plurality(cap_len, "", "s"));
 113
 114           /* Check for existences of P2P pseudo header */
 115           if (pinfo->p2p_dir != P2P_DIR_UNKNOWN) {
 116                   proto_tree_add_uint(fh_tree, hf_frame_p2p_dir, tvb,
 117                                   0, 0, pinfo->p2p_dir);
 118           }
 119         }
 120
 121
 122         TRY {
 123                 if (!dissector_try_port(wtap_encap_dissector_table, pinfo->fd->lnk_t,
 124                                         tvb, pinfo, tree)) {
 125
 126                         if (check_col(pinfo->fd, COL_PROTOCOL))
 127                                 col_set_str(pinfo->fd, COL_PROTOCOL, "UNKNOWN");
 128                         if (check_col(pinfo->fd, COL_INFO))
 129                                 col_add_fstr(pinfo->fd, COL_INFO, "WTAP_ENCAP = 0x%x", pinfo->fd->lnk_t);
 130                         dissect_data(tvb, 0, pinfo, tree);
 131                 }
 132         }
 133         CATCH(BoundsError) {
 134                 if (check_col(pinfo->fd, COL_INFO))
 135                         col_append_str(pinfo->fd, COL_INFO, "[Short Frame]");
 136                 proto_tree_add_protocol_format(tree, proto_short, tvb, 0, 0,
 137                                 "[Short Frame: %s]", pinfo->current_proto );
 138         }
 139         CATCH(ReportedBoundsError) {
 140                 if (check_col(pinfo->fd, COL_INFO))
 141                         col_append_str(pinfo->fd, COL_INFO, "[Malformed Frame]");
 142                 proto_tree_add_protocol_format(tree, proto_malformed, tvb, 0, 0,
 143                                 "[Malformed Frame: %s]", pinfo->current_proto );
 144         }
 145         ENDTRY;
 146 }
 147
 148 void
 149 proto_register_frame(void)
 150 {
 151         static hf_register_info hf[] = {
 152                 { &hf_frame_arrival_time,
 153                 { "Arrival Time",               "frame.time", FT_ABSOLUTE_TIME, BASE_NONE, NULL, 0x0,
 154                         ""}},
 155
 156                 { &hf_frame_time_delta,
 157                 { "Time delta from previous packet",    "frame.time_delta", FT_RELATIVE_TIME, BASE_NONE, NULL,
 158                         0x0,
 159                         "" }},
 160
 161                 { &hf_frame_time_relative,
 162                 { "Time relative to first packet",      "frame.time_relative", FT_RELATIVE_TIME, BASE_NONE, NULL,
 163                         0x0,
 164                         "" }},
 165
 166                 { &hf_frame_number,
 167                 { "Frame Number",               "frame.number", FT_UINT32, BASE_DEC, NULL, 0x0,
 168                         "" }},
 169
 170                 { &hf_frame_packet_len,
 171                 { "Total Frame Length",         "frame.pkt_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 172                         "" }},
 173
 174                 { &hf_frame_capture_len,
 175                 { "Capture Frame Length",       "frame.cap_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 176                         "" }},
 177
 178                 { &hf_frame_p2p_dir,
 179                 { "Point-to-Point Direction",   "frame.p2p_dir", FT_UINT8, BASE_DEC, VALS(p2p_dirs), 0x0,
 180                         "" }},
 181         };
 182         static gint *ett[] = {
 183                 &ett_frame,
 184         };
 185
 186         wtap_encap_dissector_table = register_dissector_table("wtap_encap");
 187
 188         proto_frame = proto_register_protocol("Frame", "Frame", "frame");
 189         proto_register_field_array(proto_frame, hf, array_length(hf));
 190         proto_register_subtree_array(ett, array_length(ett));
 191
 192         /* You can't disable dissection of "Frame", as that would be
 193            tantamount to not doing any dissection whatsoever. */
 194         proto_set_cant_disable(proto_frame);
 195
 196         proto_short = proto_register_protocol("Short Frame", "Short frame", "short");
 197         proto_malformed = proto_register_protocol("Malformed Frame",
 198             "Malformed frame", "malformed");
 199
 200         /* "Short Frame" and "Malformed Frame" aren't really protocols,
 201            they're error indications; disabling them makes no sense. */
 202         proto_set_cant_disable(proto_short);
 203         proto_set_cant_disable(proto_malformed);
 204 }