![Stephen Fisher](/assets/img/avatar_default.png)
Move packet-cops.c out of clean dissectors due to a #define conflict in the headers of net-snmp with our config.h svn path=/trunk/; revision=21398
719 lines
20 KiB
C
719 lines
20 KiB
C
/* packet-wcp.c
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* Routines for Wellfleet Compression frame disassembly
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* Copyright 2001, Jeffrey C. Foster <jfoste@woodward.com>
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*
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* $Id$
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*
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* ToDo:
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* Add preference to allow/disallow decompression
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* Calculate and verify check byte (last byte), if only we knew how!
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* Handle Wellfleet compression over PPP links.
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* - This will require changing the sub-dissector call
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* routine to determine if layer 2 is frame relay or
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* or PPP and different sub-dissector routines for each.
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*
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* Based upon information in the Nortel TCL based Pcaptap code.
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*http://www.mynetworkforum.com/tools/PCAPTAP/pcaptap-Win32-3.00.exe
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*
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* And lzss algorithm
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*http://www.rasip.fer.hr/research/compress/algorithms/fund/lz/lzss.html
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*/
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/*
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* Wellfleet compression is a variation on LZSS encoding.
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*
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* Compression is done by keeping a sliding window of previous
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* data transmited. The sender will use a pattern match to
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* encode repeated data as a data pointer field. Then a stream
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* of pointers and actual data bytes. The pointer values include
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* an offset to previous data in the stream and the length of the
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* matching data.
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*
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* The data pattern matching is done on the octects.
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*
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* The data is encoded as 8 field blocks with a compression flag
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* byte at the beginning. If the bit is set in the compression
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* flag, then that field has a compression field. If it isn't set
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* then the byte is raw data.
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*
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* The compression field is either 2 or 3 bytes long. The length
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* is determined by the length of the matching data, for short
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* matches the match length is encoded in the high nibble of the
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* first byte. Otherwise the third byte of the field contains
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* the match length.
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*
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* First byte -
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* lower 4 bits:
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* High order nibble of the offset
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*
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* upper 4 bits:
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* 1 = length is in 3rd byte
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* 2-F = length of matching data - 1
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*
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* Second byte -
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* Lower byte of the source offset.
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*
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* Third byte -
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* Length of match - 1 if First byte upper nibble = 1, otherwise
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* this byte isn't added to data stream.
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*
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* Example:
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* Uncompressed data (hex): 11 22 22 22 22 33 44 55 66 77
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*
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*
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* Compression data :
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* Flag bits: 0x20 (third field is compressed)
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* Data: 11 22 20 00 33 44 55
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* / / / /
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* raw data ------+--+ / /
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* (Comp length - 1)<<4+ /
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* Data offset ----------+
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*
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* Output data (hex): 20 11 22 20 00 33 44 55 66 77
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*
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* In this example the copy src is one byte behind the copy destination
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* so if appears as if output is being loaded with the source byte.
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*
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*/
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#ifdef HAVE_CONFIG_H
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# include "config.h"
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#endif
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#include <stdio.h>
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#include <glib.h>
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#include <string.h>
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#include <epan/packet.h>
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#include "packet-frame.h"
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#include <epan/circuit.h>
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#include <epan/emem.h>
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#include <epan/etypes.h>
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#include <epan/nlpid.h>
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#define MAX_WIN_BUF_LEN 0x7fff /* storage size for decompressed data */
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#define MAX_WCP_BUF_LEN 2048 /* storage size for decompressed data */
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#define FROM_DCE 0x80 /* for direction setting */
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typedef struct {
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guint8 *buf_cur;
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guint8 buffer[MAX_WIN_BUF_LEN];
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}wcp_window_t;
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typedef struct {
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wcp_window_t recv;
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wcp_window_t send;
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} wcp_circuit_data_t;
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/*XXX do I really want the length in here */
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typedef struct {
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guint16 len;
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guint8 buffer[MAX_WCP_BUF_LEN];
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}wcp_pdata_t;
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static int proto_wcp = -1;
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static int hf_wcp_cmd = -1;
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static int hf_wcp_ext_cmd = -1;
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static int hf_wcp_seq = -1;
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static int hf_wcp_chksum = -1;
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static int hf_wcp_tid = -1;
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static int hf_wcp_rev = -1;
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static int hf_wcp_init = -1;
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static int hf_wcp_seq_size = -1;
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static int hf_wcp_alg = -1;
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static int hf_wcp_alg_cnt = -1;
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static int hf_wcp_alg_a = -1;
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static int hf_wcp_alg_b = -1;
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static int hf_wcp_alg_c = -1;
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static int hf_wcp_alg_d = -1;
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static int hf_wcp_rexmit = -1;
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static int hf_wcp_hist_size = -1;
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static int hf_wcp_ppc = -1;
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static int hf_wcp_pib = -1;
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static int hf_wcp_comp_bits = -1;
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static int hf_wcp_comp_marker = -1;
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static int hf_wcp_short_len = -1;
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static int hf_wcp_long_len = -1;
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static int hf_wcp_short_run = -1;
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static int hf_wcp_long_run = -1;
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static int hf_wcp_offset = -1;
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static gint ett_wcp = -1;
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static gint ett_wcp_field = -1;
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static dissector_handle_t fr_uncompressed_handle;
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/*
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* Bits in the address field.
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*/
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#define WCP_CMD 0xf0 /* WCP Command */
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#define WCP_EXT_CMD 0x0f /* WCP Extended Command */
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#define WCP_SEQ 0x0fff /* WCP Sequence number */
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#define WCP_OFFSET_MASK 0x0fff /* WCP Pattern source offset */
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#define PPC_COMPRESSED_IND 0x0
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#define PPC_UNCOMPRESSED_IND 0x1
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#define PPC_TPPC_COMPRESSED_IND 0x2
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#define PPC_TPPC_UNCOMPRESSED_IND 0x3
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#define CONNECT_REQ 0x4
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#define CONNECT_ACK 0x5
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#define CONNECT_NAK 0x6
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#define DISCONNECT_REQ 0x7
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#define DISCONNECT_ACK 0x8
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#define INIT_REQ 0x9
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#define INIT_ACK 0xa
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#define RESET_REQ 0xb
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#define RESET_ACK 0xc
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#define REXMIT_NAK 0xd
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static const value_string cmd_string[] = {
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{0, "Compressed Data"},
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{1, "Uncompressed Data"},
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{15, "Extended"},
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{ 0, NULL }
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};
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static const value_string ext_cmd_string[] = {
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{0, "Per Packet Compression"},
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{4, "Connect Req"},
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{5, "Connect Ack"},
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{9, "Init Req"},
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{0x0a, "Init Ack"},
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{ 0, NULL }
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};
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static tvbuff_t *wcp_uncompress( tvbuff_t *src_tvb, int offset, packet_info *pinfo, proto_tree *tree);
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static wcp_window_t *get_wcp_window_ptr( packet_info *pinfo);
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static void
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dissect_wcp_con_req(tvbuff_t *tvb, int offset, proto_tree *tree) {
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/* WCP connector request message */
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guint alg_cnt = tvb_get_guint8(tvb, 5);
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proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset));
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proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2));
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proto_tree_add_uint(tree, hf_wcp_init, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3));
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proto_tree_add_uint(tree, hf_wcp_seq_size, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4));
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proto_tree_add_uint(tree, hf_wcp_alg_cnt, tvb, offset + 5, 1, alg_cnt);
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proto_tree_add_uint(tree, hf_wcp_alg_a, tvb, offset + 6, 1, tvb_get_guint8(tvb, offset + 6));
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if ( alg_cnt > 1)
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proto_tree_add_uint(tree, hf_wcp_alg_b, tvb, offset + 7, 1, tvb_get_guint8(tvb, offset + 7));
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if ( alg_cnt > 2)
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proto_tree_add_uint(tree, hf_wcp_alg_c, tvb, offset + 8, 1, tvb_get_guint8(tvb, offset + 8));
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if ( alg_cnt > 3)
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proto_tree_add_uint(tree, hf_wcp_alg_d, tvb, offset + 9, 1, tvb_get_guint8(tvb, offset + 9));
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}
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static void
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dissect_wcp_con_ack( tvbuff_t *tvb, int offset, proto_tree *tree){
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/* WCP connector ack message */
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proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset));
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proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2));
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proto_tree_add_uint(tree, hf_wcp_seq_size, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3));
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proto_tree_add_uint(tree, hf_wcp_alg, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4));
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}
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static void
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dissect_wcp_init( tvbuff_t *tvb, int offset, proto_tree *tree){
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/* WCP Initiate Request/Ack message */
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proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset));
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proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2));
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proto_tree_add_uint(tree, hf_wcp_hist_size, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3));
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proto_tree_add_uint(tree, hf_wcp_ppc, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4));
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proto_tree_add_uint(tree, hf_wcp_pib, tvb, offset + 5, 1, tvb_get_guint8(tvb, offset + 5));
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}
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static void
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dissect_wcp_reset( tvbuff_t *tvb, int offset, proto_tree *tree){
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/* Process WCP Reset Request/Ack message */
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proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset));
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}
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static void wcp_save_data( tvbuff_t *tvb, packet_info *pinfo){
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wcp_window_t *buf_ptr = 0;
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int len;
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/* discard first 2 bytes, header and last byte (check byte) */
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len = tvb_reported_length( tvb)-3;
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buf_ptr = get_wcp_window_ptr( pinfo);
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if (( buf_ptr->buf_cur + len) <= (buf_ptr->buffer + MAX_WIN_BUF_LEN)){
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tvb_memcpy( tvb, buf_ptr->buf_cur, 2, len);
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buf_ptr->buf_cur = buf_ptr->buf_cur + len;
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} else {
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guint8 *buf_end = buf_ptr->buffer + MAX_WIN_BUF_LEN;
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tvb_memcpy( tvb, buf_ptr->buf_cur, 2, buf_end - buf_ptr->buf_cur);
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tvb_memcpy( tvb, buf_ptr->buffer, buf_end - buf_ptr->buf_cur-2,
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len - (int)(buf_end - buf_ptr->buf_cur));
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buf_ptr->buf_cur = buf_ptr->buf_cur + len - MAX_WIN_BUF_LEN;
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}
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}
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static void dissect_wcp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
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proto_tree *wcp_tree;
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proto_item *ti;
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int wcp_header_len;
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guint16 temp, cmd, ext_cmd, seq;
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tvbuff_t *next_tvb;
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if (check_col(pinfo->cinfo, COL_PROTOCOL))
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "WCP");
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if (check_col(pinfo->cinfo, COL_INFO))
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col_clear(pinfo->cinfo, COL_INFO);
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temp =tvb_get_ntohs(tvb, 0);
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cmd = (temp & 0xf000) >> 12;
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ext_cmd = (temp & 0x0f00) >> 8;
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if ( cmd == 0xf)
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wcp_header_len= 1;
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else
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wcp_header_len= 2;
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seq = temp & 0x0fff;
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/*XXX should test seq to be sure it the last + 1 !! */
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if (check_col(pinfo->cinfo, COL_INFO)){
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col_add_str(pinfo->cinfo, COL_INFO, val_to_str(cmd, cmd_string, "Unknown"));
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if ( cmd == 0xf)
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col_append_fstr(pinfo->cinfo, COL_INFO, ", %s",
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val_to_str(ext_cmd, ext_cmd_string, "Unknown"));
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}
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if (tree) {
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ti = proto_tree_add_item(tree, proto_wcp, tvb, 0, wcp_header_len, FALSE);
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wcp_tree = proto_item_add_subtree(ti, ett_wcp);
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proto_tree_add_uint(wcp_tree, hf_wcp_cmd, tvb, 0, 1, tvb_get_guint8( tvb, 0));
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if ( cmd == 0xf){
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proto_tree_add_uint(wcp_tree, hf_wcp_ext_cmd, tvb, 1, 1,
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tvb_get_guint8( tvb, 0));
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switch (ext_cmd){
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case CONNECT_REQ:
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dissect_wcp_con_req( tvb, 1, wcp_tree);
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break;
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case CONNECT_ACK:
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dissect_wcp_con_ack( tvb, 1, wcp_tree);
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break;
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case INIT_REQ:
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case INIT_ACK:
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dissect_wcp_init( tvb, 1, wcp_tree);
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break;
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case RESET_REQ:
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case RESET_ACK:
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dissect_wcp_reset( tvb, 1, wcp_tree);
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break;
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default:
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break;
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}
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}else {
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proto_tree_add_uint(wcp_tree, hf_wcp_seq, tvb, 0, 2, seq);
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}
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}
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else {
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wcp_tree = NULL;
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}
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/* exit if done */
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if ( cmd != 1 && cmd != 0 && !(cmd == 0xf && ext_cmd == 0))
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return;
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if ( cmd == 1) { /* uncompressed data */
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if ( !pinfo->fd->flags.visited){ /* if first pass */
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wcp_save_data( tvb, pinfo);
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}
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next_tvb = tvb_new_subset(tvb, wcp_header_len, -1, -1);
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}
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else { /* cmd == 0 || (cmd == 0xf && ext_cmd == 0) */
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next_tvb = wcp_uncompress( tvb, wcp_header_len, pinfo, wcp_tree);
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if ( !next_tvb){
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proto_tree_add_protocol_format(tree, proto_malformed, tvb, 0, 0,
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"[Malformed Frame: Bad WCP compressed data]" );
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return;
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}
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}
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if ( tree) /* add the check byte */
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proto_tree_add_uint(wcp_tree, hf_wcp_chksum, tvb,
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tvb_reported_length( tvb)-1, 1,
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tvb_get_guint8( tvb, tvb_reported_length(tvb)-1));
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call_dissector(fr_uncompressed_handle, next_tvb, pinfo, tree);
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return;
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}
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static guint8 *decompressed_entry( guint8 *src, guint8 *dst, int *len, guint8 * buf_start, guint8 *buf_end){
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/* do the decompression for one field */
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guint16 data_offset, data_cnt;
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guint8 tmp = *src;
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data_offset = (*(src++) & 0xf) << 8; /* get high byte */
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data_offset += *(src++); /* add next byte */
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if (( tmp & 0xf0) == 0x10){ /* 2 byte count */
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data_cnt = *src;
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data_cnt++;
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}else { /* one byte count */
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data_cnt = tmp >> 4;
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data_cnt++;
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}
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src = (dst - 1 - data_offset);
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if ( src < buf_start)
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src += MAX_WIN_BUF_LEN;
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/*XXX could do some fancy memory moves, later if speed is problem */
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while( data_cnt--){
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*dst = *src;
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if ( ++(*len) >MAX_WCP_BUF_LEN){
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printf("decomp failed, len = %d\n", *len);
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return NULL; /* end of buffer error */
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}
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if ( dst++ == buf_end)
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dst = buf_start;
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if ( src++ == buf_end)
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src = buf_start;
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}
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return dst;
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}
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static
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wcp_window_t *get_wcp_window_ptr( packet_info *pinfo){
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/* find the circuit for this DLCI, create one if needed */
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/* and return the wcp_window data structure pointer */
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/* for the direction of this packet */
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circuit_t *circuit;
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wcp_circuit_data_t *wcp_circuit_data;
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circuit = find_circuit( pinfo->ctype, pinfo->circuit_id,
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pinfo->fd->num);
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if ( !circuit){
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circuit = circuit_new( pinfo->ctype, pinfo->circuit_id,
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pinfo->fd->num);
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}
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wcp_circuit_data = circuit_get_proto_data(circuit, proto_wcp);
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if ( !wcp_circuit_data){
|
|
wcp_circuit_data = se_alloc(sizeof(wcp_circuit_data_t));
|
|
wcp_circuit_data->recv.buf_cur = wcp_circuit_data->recv.buffer;
|
|
wcp_circuit_data->send.buf_cur = wcp_circuit_data->send.buffer;
|
|
circuit_add_proto_data(circuit, proto_wcp, wcp_circuit_data);
|
|
}
|
|
if (pinfo->pseudo_header->x25.flags & FROM_DCE)
|
|
return &wcp_circuit_data->recv;
|
|
else
|
|
return &wcp_circuit_data->send;
|
|
}
|
|
|
|
|
|
static tvbuff_t *wcp_uncompress( tvbuff_t *src_tvb, int offset, packet_info *pinfo, proto_tree *tree) {
|
|
|
|
/* do the packet data uncompression and load it into the dst buffer */
|
|
|
|
proto_tree *sub_tree;
|
|
proto_item *ti;
|
|
|
|
int len=0, i = -1;
|
|
int cnt = tvb_reported_length( src_tvb)-1; /* don't include check byte */
|
|
|
|
guint8 *dst, *src, *buf_start, *buf_end, *tmp, comp_flag_bits = 0;
|
|
guint8 src_buf[ MAX_WCP_BUF_LEN];
|
|
tvbuff_t *volatile tvb = 0;
|
|
wcp_window_t *buf_ptr = 0;
|
|
wcp_pdata_t *volatile pdata_ptr;
|
|
volatile gboolean bounds_error = FALSE;
|
|
|
|
buf_ptr = get_wcp_window_ptr( pinfo);
|
|
|
|
buf_start = buf_ptr->buffer;
|
|
buf_end = buf_start + MAX_WIN_BUF_LEN;
|
|
tmp = buf_ptr->buf_cur;
|
|
|
|
if (cnt - offset > MAX_WCP_BUF_LEN) {
|
|
if (tree)
|
|
proto_tree_add_text( tree, src_tvb, offset, -1,
|
|
"Compressed data exceeds maximum buffer length (%d > %d)",
|
|
cnt - offset, MAX_WCP_BUF_LEN);
|
|
return NULL;
|
|
}
|
|
|
|
src = tvb_memcpy(src_tvb, src_buf, offset, cnt - offset);
|
|
dst = buf_ptr->buf_cur;
|
|
|
|
while( offset++ < cnt){
|
|
|
|
if ( --i >= 0){
|
|
if ( comp_flag_bits & 0x80){ /* if this is a compressed entry */
|
|
|
|
if ( !pinfo->fd->flags.visited){ /* if first pass */
|
|
dst = decompressed_entry( src, dst, &len, buf_start, buf_end);
|
|
}
|
|
if ((*src & 0xf0) == 0x10){
|
|
if ( tree) {
|
|
ti = proto_tree_add_item( tree, hf_wcp_long_run, src_tvb,
|
|
offset-1, 3, 0);
|
|
sub_tree = proto_item_add_subtree(ti, ett_wcp_field);
|
|
proto_tree_add_uint(sub_tree, hf_wcp_offset, src_tvb,
|
|
offset-1, 2, pntohs(src));
|
|
|
|
proto_tree_add_item( sub_tree, hf_wcp_long_len, src_tvb,
|
|
offset+1, 1, pntohs(src));
|
|
}
|
|
src += 3;
|
|
offset += 2;
|
|
}else{
|
|
if ( tree) {
|
|
ti = proto_tree_add_item( tree, hf_wcp_short_run, src_tvb,
|
|
offset - 1, 2, *src);
|
|
sub_tree = proto_item_add_subtree(ti, ett_wcp_field);
|
|
proto_tree_add_item( sub_tree, hf_wcp_short_len, src_tvb,
|
|
offset-1, 1, *src);
|
|
proto_tree_add_uint(sub_tree, hf_wcp_offset, src_tvb,
|
|
offset-1, 2, pntohs(src));
|
|
}
|
|
src += 2;
|
|
offset += 1;
|
|
}
|
|
}else {
|
|
if ( !pinfo->fd->flags.visited){ /* if first pass */
|
|
*dst = *src;
|
|
if ( dst++ == buf_end)
|
|
dst = buf_start;
|
|
}
|
|
++src;
|
|
++len;
|
|
|
|
}
|
|
|
|
if ( len >MAX_WCP_BUF_LEN){
|
|
return NULL;
|
|
}
|
|
|
|
comp_flag_bits <<= 1;
|
|
|
|
}else { /* compressed data flag */
|
|
|
|
comp_flag_bits = *src++;
|
|
if (tree)
|
|
proto_tree_add_uint( tree, hf_wcp_comp_bits, src_tvb, offset-1, 1,
|
|
comp_flag_bits);
|
|
|
|
i = 8;
|
|
}
|
|
}
|
|
|
|
if ( pinfo->fd->flags.visited){ /* if not first pass */
|
|
/* get uncompressed data */
|
|
pdata_ptr = p_get_proto_data( pinfo->fd, proto_wcp);
|
|
|
|
if ( !pdata_ptr) /* exit if no data */
|
|
return NULL;
|
|
len = pdata_ptr->len;
|
|
} else {
|
|
|
|
/* save the new data as per packet data */
|
|
pdata_ptr = se_alloc(sizeof(wcp_pdata_t));
|
|
memcpy( &pdata_ptr->buffer, buf_ptr->buf_cur, len);
|
|
pdata_ptr->len = len;
|
|
|
|
p_add_proto_data( pinfo->fd, proto_wcp, (void*)pdata_ptr);
|
|
|
|
buf_ptr->buf_cur = dst;
|
|
}
|
|
|
|
|
|
TRY {
|
|
tvb = tvb_new_real_data( pdata_ptr->buffer, pdata_ptr->len, pdata_ptr->len);
|
|
}
|
|
CATCH(BoundsError) {
|
|
DISSECTOR_ASSERT_NOT_REACHED();
|
|
}
|
|
CATCH(ReportedBoundsError) {
|
|
bounds_error = TRUE;
|
|
}
|
|
ENDTRY;
|
|
|
|
if (bounds_error) return NULL;
|
|
|
|
/* link new tvbuff into tvbuff chain so cleanup is done later */
|
|
tvb_set_child_real_data_tvbuff( src_tvb, tvb);
|
|
|
|
/* Add new data to the data source list */
|
|
add_new_data_source( pinfo, tvb, "Uncompressed WCP");
|
|
return tvb;
|
|
|
|
}
|
|
|
|
|
|
void
|
|
proto_register_wcp(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_wcp_cmd,
|
|
{ "Command", "wcp.cmd", FT_UINT8, BASE_HEX, VALS(cmd_string), WCP_CMD,
|
|
"Compression Command", HFILL }},
|
|
{ &hf_wcp_ext_cmd,
|
|
{ "Extended Command", "wcp.ext_cmd", FT_UINT8, BASE_HEX, VALS(ext_cmd_string), WCP_EXT_CMD,
|
|
"Extended Compression Command", HFILL }},
|
|
{ &hf_wcp_seq,
|
|
{ "SEQ", "wcp.seq", FT_UINT16, BASE_HEX, NULL, WCP_SEQ,
|
|
"Sequence Number", HFILL }},
|
|
{ &hf_wcp_chksum,
|
|
{ "Checksum", "wcp.checksum", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Packet Checksum", HFILL }},
|
|
{ &hf_wcp_tid,
|
|
{ "TID", "wcp.tid", FT_UINT16, BASE_DEC, NULL, 0,
|
|
"TID", HFILL }},
|
|
{ &hf_wcp_rev,
|
|
{ "Revision", "wcp.rev", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Revision", HFILL }},
|
|
{ &hf_wcp_init,
|
|
{ "Initiator", "wcp.init", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Initiator", HFILL }},
|
|
{ &hf_wcp_seq_size,
|
|
{ "Seq Size", "wcp.seq_size", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Sequence Size", HFILL }},
|
|
{ &hf_wcp_alg_cnt,
|
|
{ "Alg Count", "wcp.alg_cnt", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm Count", HFILL }},
|
|
{ &hf_wcp_alg_a,
|
|
{ "Alg 1", "wcp.alg1", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm #1", HFILL }},
|
|
{ &hf_wcp_alg_b,
|
|
{ "Alg 2", "wcp.alg2", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm #2", HFILL }},
|
|
{ &hf_wcp_alg_c,
|
|
{ "Alg 3", "wcp.alg3", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm #3", HFILL }},
|
|
{ &hf_wcp_alg_d,
|
|
{ "Alg 4", "wcp.alg4", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm #4", HFILL }},
|
|
{ &hf_wcp_alg,
|
|
{ "Alg", "wcp.alg", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Algorithm", HFILL }},
|
|
{ &hf_wcp_rexmit,
|
|
{ "Rexmit", "wcp.rexmit", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Retransmit", HFILL }},
|
|
{ &hf_wcp_hist_size,
|
|
{ "History", "wcp.hist", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"History Size", HFILL }},
|
|
{ &hf_wcp_ppc,
|
|
{ "PerPackComp", "wcp.ppc", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Per Packet Compression", HFILL }},
|
|
{ &hf_wcp_pib,
|
|
{ "PIB", "wcp.pib", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"PIB", HFILL }},
|
|
{ &hf_wcp_comp_bits,
|
|
{ "Compress Flag", "wcp.flag", FT_UINT8, BASE_HEX, NULL, 0,
|
|
"Compressed byte flag", HFILL }},
|
|
{ &hf_wcp_comp_marker,
|
|
{ "Compress Marker", "wcp.mark", FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Compressed marker", HFILL }},
|
|
{ &hf_wcp_offset,
|
|
{ "Source offset", "wcp.off", FT_UINT16, BASE_HEX, NULL, WCP_OFFSET_MASK,
|
|
"Data source offset", HFILL }},
|
|
{ &hf_wcp_short_len,
|
|
{ "Compress Length", "wcp.short_len", FT_UINT8, BASE_HEX, NULL, 0xf0,
|
|
"Compressed length", HFILL }},
|
|
{ &hf_wcp_long_len,
|
|
{ "Compress Length", "wcp.long_len", FT_UINT8, BASE_HEX, NULL, 0,
|
|
"Compressed length", HFILL }},
|
|
{ &hf_wcp_long_run,
|
|
{ "Long Compression", "wcp.long_comp", FT_UINT16, BASE_HEX, NULL, 0,
|
|
"Long Compression type", HFILL }},
|
|
{ &hf_wcp_short_run,
|
|
{ "Short Compression", "wcp.short_comp", FT_UINT8, BASE_HEX, NULL, 0,
|
|
"Short Compression type", HFILL }},
|
|
|
|
};
|
|
|
|
|
|
static gint *ett[] = {
|
|
&ett_wcp,
|
|
&ett_wcp_field,
|
|
};
|
|
|
|
proto_wcp = proto_register_protocol ("Wellfleet Compression", "WCP", "wcp");
|
|
proto_register_field_array (proto_wcp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
}
|
|
|
|
|
|
void
|
|
proto_reg_handoff_wcp(void) {
|
|
dissector_handle_t wcp_handle;
|
|
|
|
/*
|
|
* Get handle for the Frame Relay (uncompressed) dissector.
|
|
*/
|
|
fr_uncompressed_handle = find_dissector("fr_uncompressed");
|
|
|
|
wcp_handle = create_dissector_handle(dissect_wcp, proto_wcp);
|
|
dissector_add("fr.ietf", NLPID_COMPRESSED, wcp_handle);
|
|
dissector_add("ethertype", ETHERTYPE_WCP, wcp_handle);
|
|
}
|