/* packet-wcp.c * Routines for Wellfleet Compression frame disassembly * Copyright 2001, Jeffrey C. Foster * * $Id: packet-wcp.c,v 1.31 2003/01/31 03:17:47 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs * Copyright 1998 * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * ToDo: * Add preference to allow/disallow decompression * Calculate and verify check byte (last byte), if only we knew how! * Handle Wellfleet compression over PPP links. * - This will require changing the sub-dissector call * routine to determine if layer 2 is frame relay or * or PPP and different sub-dissector routines for each. * * Based upon information in the Nortel TCL based Pcaptap code. *http://www.mynetworkforum.com/tools/PCAPTAP/pcaptap-Win32-3.00.exe * * And lzss algorithm *http://www.rasip.fer.hr/research/compress/algorithms/fund/lz/lzss.html */ /* * Wellfleet compression is a variation on LZSS encoding. * * Compression is done by keeping a sliding window of previous * data transmited. The sender will use a pattern match to * encode repeated data as a data pointer field. Then a stream * of pointers and actual data bytes. The pointer values include * an offset to previous data in the stream and the length of the * matching data. * * The data pattern matching is done on the octects. * * The data is encoded as 8 field blocks with a compression flag * byte at the beginning. If the bit is set in the compression * flag, then that field has a compression field. If it isn't set * then the byte is raw data. * * The compression field is either 2 or 3 bytes long. The length * is determined by the length of the matching data, for short * matches the match length is encoded in the high nibble of the * first byte. Otherwise the third byte of the field contains * the match length. * * First byte - * lower 4 bits: * High order nibble of the offset * * upper 4 bits: * 1 = length is in 3rd byte * 2-F = length of matching data - 1 * * Second byte - * Lower byte of the source offset. * * Third byte - * Length of match - 1 if First byte upper nibble = 1, otherwise * this byte isn't added to data stream. * * Example: * Uncompressed data (hex): 11 22 22 22 22 33 44 55 66 77 * * * Compression data : * Flag bits: 0x20 (third field is compressed) * Data: 11 22 20 00 33 44 55 * / / / / * raw data ------+--+ / / * (Comp length - 1)<<4+ / * Data offset ----------+ * * Output data (hex): 20 11 22 20 00 33 44 55 66 77 * * In this example the copy src is one byte behind the copy destination * so if appears as if output is being loaded with the source byte. * */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include #include #include #include #include "packet-frame.h" #include #include "etypes.h" #include "nlpid.h" #define MAX_WIN_BUF_LEN 0x7fff /* storage size for decompressed data */ #define MAX_WCP_BUF_LEN 2048 /* storage size for decompressed data */ #define FROM_DCE 0x80 /* for direction setting */ typedef struct { guint8 *buf_cur; guint8 buffer[MAX_WIN_BUF_LEN]; }wcp_window_t; typedef struct { wcp_window_t recv; wcp_window_t send; } wcp_circuit_data_t; /*XXX do I really want the length in here */ typedef struct { guint16 len; guint8 buffer[MAX_WCP_BUF_LEN]; }wcp_pdata_t; #define wcp_win_init_count 4 #define wcp_packet_init_count 10 #define wcp_circuit_length (sizeof(wcp_circuit_data_t)) #define wcp_packet_length (sizeof(wcp_pdata_t)) static GMemChunk *wcp_circuit = NULL; static GMemChunk *wcp_pdata = NULL; static int proto_wcp = -1; static int hf_wcp_cmd = -1; static int hf_wcp_ext_cmd = -1; static int hf_wcp_seq = -1; static int hf_wcp_chksum = -1; static int hf_wcp_tid = -1; static int hf_wcp_rev = -1; static int hf_wcp_init = -1; static int hf_wcp_seq_size = -1; static int hf_wcp_alg = -1; static int hf_wcp_alg_cnt = -1; static int hf_wcp_alg_a = -1; static int hf_wcp_alg_b = -1; static int hf_wcp_alg_c = -1; static int hf_wcp_alg_d = -1; static int hf_wcp_rexmit = -1; static int hf_wcp_hist_size = -1; static int hf_wcp_ppc = -1; static int hf_wcp_pib = -1; static int hf_wcp_comp_bits = -1; static int hf_wcp_comp_marker = -1; static int hf_wcp_short_len = -1; static int hf_wcp_long_len = -1; static int hf_wcp_short_run = -1; static int hf_wcp_long_run = -1; static int hf_wcp_offset = -1; static gint ett_wcp = -1; static gint ett_wcp_field = -1; static dissector_handle_t fr_uncompressed_handle; /* * Bits in the address field. */ #define WCP_CMD 0xf0 /* WCP Command */ #define WCP_EXT_CMD 0x0f /* WCP Extended Command */ #define WCP_SEQ 0x0fff /* WCP Sequence number */ #define WCP_OFFSET_MASK 0x0fff /* WCP Pattern source offset */ #define PPC_COMPRESSED_IND 0x0 #define PPC_UNCOMPRESSED_IND 0x1 #define PPC_TPPC_COMPRESSED_IND 0x2 #define PPC_TPPC_UNCOMPRESSED_IND 0x3 #define CONNECT_REQ 0x4 #define CONNECT_ACK 0x5 #define CONNECT_NAK 0x6 #define DISCONNECT_REQ 0x7 #define DISCONNECT_ACK 0x8 #define INIT_REQ 0x9 #define INIT_ACK 0xa #define RESET_REQ 0xb #define RESET_ACK 0xc #define REXMIT_NAK 0xd static const value_string cmd_string[] = { {0, "Compressed Data"}, {1, "Uncompressed Data"}, {15, "Extended"}, { 0, NULL } }; static const value_string ext_cmd_string[] = { {0, "Per Packet Compression"}, {4, "Connect Req"}, {5, "Connect Ack"}, {9, "Init Req"}, {0x0a, "Init Ack"}, { 0, NULL } }; static tvbuff_t *wcp_uncompress( tvbuff_t *src_tvb, int offset, packet_info *pinfo, proto_tree *tree); static wcp_window_t *get_wcp_window_ptr( packet_info *pinfo); static void dissect_wcp_con_req(tvbuff_t *tvb, int offset, proto_tree *tree) { /* WCP connector request message */ guint alg_cnt = tvb_get_guint8(tvb, 5); proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset)); proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2)); proto_tree_add_uint(tree, hf_wcp_init, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3)); proto_tree_add_uint(tree, hf_wcp_seq_size, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4)); proto_tree_add_uint(tree, hf_wcp_alg_cnt, tvb, offset + 5, 1, alg_cnt); proto_tree_add_uint(tree, hf_wcp_alg_a, tvb, offset + 6, 1, tvb_get_guint8(tvb, offset + 6)); if ( alg_cnt > 1) proto_tree_add_uint(tree, hf_wcp_alg_b, tvb, offset + 7, 1, tvb_get_guint8(tvb, offset + 7)); if ( alg_cnt > 2) proto_tree_add_uint(tree, hf_wcp_alg_c, tvb, offset + 8, 1, tvb_get_guint8(tvb, offset + 8)); if ( alg_cnt > 3) proto_tree_add_uint(tree, hf_wcp_alg_d, tvb, offset + 9, 1, tvb_get_guint8(tvb, offset + 9)); } static void dissect_wcp_con_ack( tvbuff_t *tvb, int offset, proto_tree *tree){ /* WCP connector ack message */ proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset)); proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2)); proto_tree_add_uint(tree, hf_wcp_seq_size, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3)); proto_tree_add_uint(tree, hf_wcp_alg, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4)); } static void dissect_wcp_init( tvbuff_t *tvb, int offset, proto_tree *tree){ /* WCP Initiate Request/Ack message */ proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset)); proto_tree_add_uint(tree, hf_wcp_rev, tvb, offset + 2, 1, tvb_get_guint8(tvb, offset + 2)); proto_tree_add_uint(tree, hf_wcp_hist_size, tvb, offset + 3, 1, tvb_get_guint8(tvb, offset + 3)); proto_tree_add_uint(tree, hf_wcp_ppc, tvb, offset + 4, 1, tvb_get_guint8(tvb, offset + 4)); proto_tree_add_uint(tree, hf_wcp_pib, tvb, offset + 5, 1, tvb_get_guint8(tvb, offset + 5)); } static void dissect_wcp_reset( tvbuff_t *tvb, int offset, proto_tree *tree){ /* Process WCP Reset Request/Ack message */ proto_tree_add_uint(tree, hf_wcp_tid, tvb, offset, 2, tvb_get_ntohs(tvb, offset)); } static void wcp_save_data( tvbuff_t *tvb, packet_info *pinfo){ wcp_window_t *buf_ptr = 0; int len; /* discard first 2 bytes, header and last byte (check byte) */ len = tvb_reported_length( tvb)-3; buf_ptr = get_wcp_window_ptr( pinfo); if (( buf_ptr->buf_cur + len) <= (buf_ptr->buffer + MAX_WIN_BUF_LEN)){ tvb_memcpy( tvb, buf_ptr->buf_cur, 2, len); buf_ptr->buf_cur = buf_ptr->buf_cur + len; } else { guint8 *buf_end = buf_ptr->buffer + MAX_WIN_BUF_LEN; tvb_memcpy( tvb, buf_ptr->buf_cur, 2, buf_end - buf_ptr->buf_cur); tvb_memcpy( tvb, buf_ptr->buffer, buf_end - buf_ptr->buf_cur-2, len - (int)(buf_end - buf_ptr->buf_cur)); buf_ptr->buf_cur = buf_ptr->buf_cur + len - MAX_WIN_BUF_LEN; } } static void dissect_wcp( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { proto_tree *wcp_tree; proto_item *ti; int wcp_header_len; guint16 temp, cmd, ext_cmd, seq; tvbuff_t *next_tvb; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "WCP"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); temp =tvb_get_ntohs(tvb, 0); cmd = (temp & 0xf000) >> 12; ext_cmd = (temp & 0x0f00) >> 8; if ( cmd == 0xf) wcp_header_len= 1; else wcp_header_len= 2; seq = temp & 0x0fff; /*XXX should test seq to be sure it the last + 1 !! */ if (check_col(pinfo->cinfo, COL_INFO)){ col_add_str(pinfo->cinfo, COL_INFO, val_to_str(cmd, cmd_string, "Unknown")); if ( cmd == 0xf) col_append_fstr(pinfo->cinfo, COL_INFO, ", %s", val_to_str(ext_cmd, ext_cmd_string, "Unknown")); } if (tree) { ti = proto_tree_add_item(tree, proto_wcp, tvb, 0, wcp_header_len, FALSE); wcp_tree = proto_item_add_subtree(ti, ett_wcp); proto_tree_add_uint(wcp_tree, hf_wcp_cmd, tvb, 0, 1, tvb_get_guint8( tvb, 0)); if ( cmd == 0xf){ proto_tree_add_uint(wcp_tree, hf_wcp_ext_cmd, tvb, 1, 1, tvb_get_guint8( tvb, 0)); switch (ext_cmd){ case CONNECT_REQ: dissect_wcp_con_req( tvb, 1, wcp_tree); break; case CONNECT_ACK: dissect_wcp_con_ack( tvb, 1, wcp_tree); break; case INIT_REQ: case INIT_ACK: dissect_wcp_init( tvb, 1, wcp_tree); break; case RESET_REQ: case RESET_ACK: dissect_wcp_reset( tvb, 1, wcp_tree); break; default: break; } }else { proto_tree_add_uint(wcp_tree, hf_wcp_seq, tvb, 0, 2, seq); } } else { wcp_tree = NULL; } /* exit if done */ if ( cmd != 1 && cmd != 0 && !(cmd == 0xf && ext_cmd == 0)) return; if ( cmd == 1) { /* uncompressed data */ if ( !pinfo->fd->flags.visited){ /* if first pass */ wcp_save_data( tvb, pinfo); } next_tvb = tvb_new_subset(tvb, wcp_header_len, -1, -1); } else { /* cmd == 0 || (cmd == 0xf && ext_cmd == 0) */ next_tvb = wcp_uncompress( tvb, wcp_header_len, pinfo, wcp_tree); if ( !next_tvb){ proto_tree_add_protocol_format(tree, proto_malformed, tvb, 0, 0, "[Malformed Frame: Bad WCP compressed data]" ); return; } } if ( tree) /* add the check byte */ proto_tree_add_uint(wcp_tree, hf_wcp_chksum, tvb, tvb_reported_length( tvb)-1, 1, tvb_get_guint8( tvb, tvb_reported_length(tvb)-1)); call_dissector(fr_uncompressed_handle, next_tvb, pinfo, tree); return; } static guint8 *decompressed_entry( guint8 *src, guint8 *dst, int *len, guint8 * buf_start, guint8 *buf_end){ /* do the decompression for one field */ guint16 data_offset, data_cnt; guint8 tmp = *src; data_offset = (*(src++) & 0xf) << 8; /* get high byte */ data_offset += *(src++); /* add next byte */ if (( tmp & 0xf0) == 0x10){ /* 2 byte count */ data_cnt = *src; data_cnt++; }else { /* one byte count */ data_cnt = tmp >> 4; data_cnt++; } src = (dst - 1 - data_offset); if ( src < buf_start) src += MAX_WIN_BUF_LEN; /*XXX could do some fancy memory moves, later if speed is problem */ while( data_cnt--){ *dst = *src; if ( ++(*len) >MAX_WCP_BUF_LEN){ printf("decomp failed, len = %d\n", *len); return NULL; /* end of buffer error */ } if ( dst++ == buf_end) dst = buf_start; if ( src++ == buf_end) src = buf_start; } return dst; } static wcp_window_t *get_wcp_window_ptr( packet_info *pinfo){ /* find the circuit for this DLCI, create one if needed */ /* and return the wcp_window data structure pointer */ /* for the direction of this packet */ circuit_t *circuit; wcp_circuit_data_t *wcp_circuit_data; circuit = find_circuit( pinfo->ctype, pinfo->circuit_id, pinfo->fd->num); if ( !circuit){ circuit = circuit_new( pinfo->ctype, pinfo->circuit_id, pinfo->fd->num); } wcp_circuit_data = circuit_get_proto_data(circuit, proto_wcp); if ( !wcp_circuit_data){ wcp_circuit_data = g_mem_chunk_alloc( wcp_circuit); 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 *buf = 0, *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; 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 = g_mem_chunk_alloc( wcp_pdata); 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) { g_assert_not_reached(); g_free(buf); return NULL; } CATCH(ReportedBoundsError) { g_free(buf); return NULL; } ENDTRY; /* 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; } static void wcp_reinit( void){ /* Do the cleanup work when a new pass through the packet list is */ /* performed. re-initialize the memory chunks. */ if (wcp_circuit) g_mem_chunk_destroy(wcp_circuit); wcp_circuit = g_mem_chunk_new("wcp_circuit", wcp_circuit_length, wcp_win_init_count * wcp_circuit_length, G_ALLOC_AND_FREE); if (wcp_pdata) g_mem_chunk_destroy(wcp_pdata); wcp_pdata = g_mem_chunk_new("wcp_pdata", wcp_packet_length, wcp_packet_init_count * wcp_packet_length, G_ALLOC_AND_FREE); } 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)); register_init_routine(&wcp_reinit); } 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); }