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 1.3 2000/11/29 05:16:15 gram 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_number = -1;
  41 static int hf_frame_packet_len = -1;
  42 static int hf_frame_capture_len = -1;
  43 static int hf_frame_p2p_dir = -1;
  44 static int proto_short = -1;
  45 int proto_malformed = -1;
  46
  47 static gint ett_frame = -1;
  48
  49 static const value_string p2p_dirs[] = {
  50         { P2P_DIR_SENT, "Sent" },
  51         { P2P_DIR_RECV, "Received" },
  52         { 0, NULL }
  53 };
  54
  55 static dissector_table_t wtap_encap_dissector_table;
  56
  57 void
  58 dissect_frame(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  59 {
  60         proto_tree      *fh_tree;
  61         proto_item      *ti;
  62         struct timeval  tv;
  63         int             cap_len, pkt_len;
  64
  65         pinfo->current_proto = "Frame";
  66
  67         if (pinfo->fd->lnk_t == WTAP_ENCAP_LAPD ||
  68                         pinfo->fd->lnk_t == WTAP_ENCAP_PPP_WITH_PHDR) {
  69
  70                 pinfo->p2p_dir = pinfo->pseudo_header->p2p.sent ? P2P_DIR_SENT : P2P_DIR_RECV;
  71         }
  72
  73         /* Put in frame header information. */
  74         if (tree) {
  75
  76           cap_len = tvb_length(tvb);
  77           pkt_len = tvb_reported_length(tvb);
  78
  79           ti = proto_tree_add_protocol_format(tree, proto_frame, tvb, 0, tvb_length(tvb),
  80             "Frame %u (%u on wire, %u captured)", pinfo->fd->num, pkt_len, cap_len);
  81
  82           fh_tree = proto_item_add_subtree(ti, ett_frame);
  83
  84           tv.tv_sec = pinfo->fd->abs_secs;
  85           tv.tv_usec = pinfo->fd->abs_usecs;
  86
  87           proto_tree_add_time(fh_tree, hf_frame_arrival_time, tvb,
  88                 0, 0, &tv);
  89
  90           tv.tv_sec = pinfo->fd->del_secs;
  91           tv.tv_usec = pinfo->fd->del_usecs;
  92
  93           proto_tree_add_time(fh_tree, hf_frame_time_delta, tvb,
  94                 0, 0, &tv);
  95
  96           proto_tree_add_uint(fh_tree, hf_frame_number, tvb,
  97                 0, 0, pinfo->fd->num);
  98
  99           proto_tree_add_uint_format(fh_tree, hf_frame_packet_len, tvb,
 100                 0, 0, pkt_len, "Packet Length: %d byte%s", pkt_len,
 101                 plurality(pkt_len, "", "s"));
 102
 103           proto_tree_add_uint_format(fh_tree, hf_frame_capture_len, tvb,
 104                 0, 0, cap_len, "Capture Length: %d byte%s", cap_len,
 105                 plurality(cap_len, "", "s"));
 106
 107           /* Check for existences of P2P pseudo header */
 108           if (pinfo->p2p_dir != P2P_DIR_UNKNOWN) {
 109                   proto_tree_add_uint(fh_tree, hf_frame_p2p_dir, tvb,
 110                                   0, 0, pinfo->p2p_dir);
 111           }
 112         }
 113
 114
 115         TRY {
 116                 if (!dissector_try_port(wtap_encap_dissector_table, pinfo->fd->lnk_t,
 117                                         tvb, pinfo, tree)) {
 118
 119                         if (check_col(pinfo->fd, COL_PROTOCOL))
 120                                 col_set_str(pinfo->fd, COL_PROTOCOL, "UNKNOWN");
 121                         if (check_col(pinfo->fd, COL_INFO))
 122                                 col_add_fstr(pinfo->fd, COL_INFO, "WTAP_ENCAP = 0x%x", pinfo->fd->lnk_t);
 123                         dissect_data(tvb, 0, pinfo, tree);
 124                 }
 125         }
 126         CATCH(BoundsError) {
 127                 proto_tree_add_protocol_format(tree, proto_short, tvb, 0, 0,
 128                                 "[Short Frame: %s]", pinfo->current_proto );
 129         }
 130         CATCH(ReportedBoundsError) {
 131                 proto_tree_add_protocol_format(tree, proto_malformed, tvb, 0, 0,
 132                                 "[Malformed Frame: %s]", pinfo->current_proto );
 133         }
 134         ENDTRY;
 135 }
 136
 137 void
 138 proto_register_frame(void)
 139 {
 140         static hf_register_info hf[] = {
 141                 { &hf_frame_arrival_time,
 142                 { "Arrival Time",               "frame.time", FT_ABSOLUTE_TIME, BASE_NONE, NULL, 0x0,
 143                         ""}},
 144
 145                 { &hf_frame_time_delta,
 146                 { "Time delta from previous packet",    "frame.time_delta", FT_RELATIVE_TIME, BASE_NONE, NULL,
 147                         0x0,
 148                         "" }},
 149
 150                 { &hf_frame_number,
 151                 { "Frame Number",               "frame.number", FT_UINT32, BASE_DEC, NULL, 0x0,
 152                         "" }},
 153
 154                 { &hf_frame_packet_len,
 155                 { "Total Frame Length",         "frame.pkt_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 156                         "" }},
 157
 158                 { &hf_frame_capture_len,
 159                 { "Capture Frame Length",       "frame.cap_len", FT_UINT32, BASE_DEC, NULL, 0x0,
 160                         "" }},
 161
 162                 { &hf_frame_p2p_dir,
 163                 { "Point-to-Point Direction",   "frame.p2p_dir", FT_UINT8, BASE_DEC, VALS(p2p_dirs), 0x0,
 164                         "" }},
 165         };
 166         static gint *ett[] = {
 167                 &ett_frame,
 168         };
 169
 170         wtap_encap_dissector_table = register_dissector_table("wtap_encap");
 171
 172         proto_frame = proto_register_protocol("Frame", "frame");
 173         proto_register_field_array(proto_frame, hf, array_length(hf));
 174         proto_register_subtree_array(ett, array_length(ett));
 175
 176         proto_short = proto_register_protocol("Short Frame", "short");
 177         proto_malformed = proto_register_protocol("Malformed Frame", "malformed");
 178
 179 }