diff options
Diffstat (limited to 'epan/dissectors/packet-wcp.c')
| -rw-r--r-- | epan/dissectors/packet-wcp.c | 797 |
1 files changed, 797 insertions, 0 deletions
diff --git a/epan/dissectors/packet-wcp.c b/epan/dissectors/packet-wcp.c new file mode 100644 index 00000000..50cf090b --- /dev/null +++ b/epan/dissectors/packet-wcp.c @@ -0,0 +1,797 @@ +/* packet-wcp.c + * Routines for Wellfleet Compression frame disassembly + * Copyright 2001, Jeffrey C. Foster <jfoste@woodward.com> + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 + * + * SPDX-License-Identifier: GPL-2.0-or-later + * + * 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 octets. + * + * 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. + * + */ + + + +#include "config.h" + + +#include <epan/packet.h> +#include <epan/proto_data.h> + +#include <wiretap/wtap.h> +#include <wsutil/pint.h> +#include <epan/conversation.h> +#include <epan/etypes.h> +#include <epan/nlpid.h> +#include <epan/expert.h> +#include <epan/exceptions.h> + +#define MAX_WIN_BUF_LEN 0x7fff /* storage size for decompressed data */ +#define MAX_WCP_BUF_LEN 2048 /* storage size for compressed data */ +#define FROM_DCE 0x80 /* for direction setting */ + +void proto_register_wcp(void); +void proto_reg_handoff_wcp(void); + +typedef struct { + guint8 *buf_cur; + guint8 buffer[MAX_WIN_BUF_LEN]; + /* initialized bytes in the buffer (since buf_cur may wrap around) */ + guint16 initialized; +} 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; + + +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_compressed_data = -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_comp_data = -1; +static gint ett_wcp_field = -1; + +static expert_field ei_wcp_compressed_data_exceeds = EI_INIT; +static expert_field ei_wcp_uncompressed_data_exceeds = EI_INIT; +static expert_field ei_wcp_invalid_window_offset = EI_INIT; +static expert_field ei_wcp_buffer_too_long = EI_INIT; +/* static expert_field ei_wcp_invalid_match_length = EI_INIT; */ + +static dissector_handle_t wcp_handle; +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 */ + guint32 alg_cnt; + + proto_tree_add_item(tree, hf_wcp_tid, tvb, offset, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_wcp_rev, tvb, offset + 2, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_init, tvb, offset + 3, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_seq_size, tvb, offset + 4, 1, ENC_NA); + proto_tree_add_item_ret_uint(tree, hf_wcp_alg_cnt, tvb, offset + 5, 1, ENC_NA, &alg_cnt); + proto_tree_add_item(tree, hf_wcp_alg_a, tvb, offset + 6, 1, ENC_NA); + if (alg_cnt > 1) + proto_tree_add_item(tree, hf_wcp_alg_b, tvb, offset + 7, 1, ENC_NA); + if (alg_cnt > 2) + proto_tree_add_item(tree, hf_wcp_alg_c, tvb, offset + 8, 1, ENC_NA); + if (alg_cnt > 3) + proto_tree_add_item(tree, hf_wcp_alg_d, tvb, offset + 9, 1, ENC_NA); +} + +static void +dissect_wcp_con_ack(tvbuff_t *tvb, int offset, proto_tree *tree) { + + /* WCP connector ack message */ + + proto_tree_add_item(tree, hf_wcp_tid, tvb, offset, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_wcp_rev, tvb, offset + 2, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_seq_size, tvb, offset + 3, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_alg, tvb, offset + 4, 1, ENC_NA); +} + +static void +dissect_wcp_init(tvbuff_t *tvb, int offset, proto_tree *tree) { + + /* WCP Initiate Request/Ack message */ + + proto_tree_add_item(tree, hf_wcp_tid, tvb, offset, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_wcp_rev, tvb, offset + 2, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_hist_size, tvb, offset + 3, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_ppc, tvb, offset + 4, 1, ENC_NA); + proto_tree_add_item(tree, hf_wcp_pib, tvb, offset + 5, 1, ENC_NA); +} + + +static void +dissect_wcp_reset(tvbuff_t *tvb, int offset, proto_tree *tree) { + + /* Process WCP Reset Request/Ack message */ + + proto_tree_add_item(tree, hf_wcp_tid, tvb, offset, 2, ENC_BIG_ENDIAN); +} + + +static void wcp_save_data(tvbuff_t *tvb, packet_info *pinfo, proto_tree* tree) { + + wcp_window_t *buf_ptr = 0; + size_t 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 += 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); + if (buf_ptr->buf_cur + len <= buf_end) { + tvb_memcpy(tvb, buf_ptr->buffer, (gint) (buf_end - buf_ptr->buf_cur-2), + len - (buf_end - buf_ptr->buf_cur)); + buf_ptr->buf_cur += len - MAX_WIN_BUF_LEN; + } else { + proto_tree_add_expert(tree, pinfo, &ei_wcp_buffer_too_long, tvb, 0, -1); + } + } +} + + +static int dissect_wcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { + + proto_tree *wcp_tree; + proto_item *ti; + int wcp_header_len; + guint16 temp, cmd, ext_cmd, seq; + tvbuff_t *next_tvb; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "WCP"); + 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 !! */ + + col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(cmd, cmd_string, "Unknown")); + if (cmd == 0xf) + col_append_fstr(pinfo->cinfo, COL_INFO, ", %s", + val_to_str_const(ext_cmd, ext_cmd_string, "Unknown")); + + ti = proto_tree_add_item(tree, proto_wcp, tvb, 0, wcp_header_len, ENC_NA); + wcp_tree = proto_item_add_subtree(ti, ett_wcp); + + proto_tree_add_item(wcp_tree, hf_wcp_cmd, tvb, 0, 1, ENC_NA); + if (cmd == 0xf) { + proto_tree_add_item(wcp_tree, hf_wcp_ext_cmd, tvb, 1, 1, ENC_NA); + 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); + } + + + /* exit if done */ + if (cmd != 1 && cmd != 0 && !(cmd == 0xf && ext_cmd == 0)) + return 2; + + if (cmd == 1) { /* uncompressed data */ + if (!pinfo->fd->visited) { /* if first pass */ + wcp_save_data(tvb, pinfo, wcp_tree); + } + next_tvb = tvb_new_subset_remaining(tvb, wcp_header_len); + } else { /* cmd == 0 || (cmd == 0xf && ext_cmd == 0) */ + + next_tvb = wcp_uncompress(tvb, wcp_header_len, pinfo, wcp_tree); + + if (!next_tvb) { + return tvb_captured_length(tvb); + } + } + + /* add the check byte */ + proto_tree_add_checksum(wcp_tree, tvb, tvb_reported_length(tvb) - 1, hf_wcp_chksum, -1, NULL, pinfo, 0, ENC_NA, PROTO_CHECKSUM_NO_FLAGS); + + call_dissector(fr_uncompressed_handle, next_tvb, pinfo, tree); + + return tvb_captured_length(tvb); +} + + +static guint8 * +decompressed_entry(guint8 *dst, guint16 data_offset, + guint16 data_cnt, int *len, wcp_window_t *buf_ptr) +{ + const guint8 *src; + guint8 *buf_start, *buf_end; + + buf_start = buf_ptr->buffer; + buf_end = buf_ptr->buffer + MAX_WIN_BUF_LEN; + + /* do the decompression for one field */ + + 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 (buf_ptr->initialized < MAX_WIN_BUF_LEN) + buf_ptr->initialized++; + if ( ++(*len) >MAX_WCP_BUF_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 */ + + conversation_t *conv; + wcp_circuit_data_t *wcp_circuit_data; + + conv = find_or_create_conversation(pinfo); + + wcp_circuit_data = (wcp_circuit_data_t *)conversation_get_proto_data(conv, proto_wcp); + if (!wcp_circuit_data) { + wcp_circuit_data = wmem_new0(wmem_file_scope(), 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; + conversation_add_proto_data(conv, proto_wcp, wcp_circuit_data); + } + if (pinfo->pseudo_header->dte_dce.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 *cd_tree, *sub_tree; + proto_item *cd_item, *ti; + + int len, i; + int cnt = tvb_reported_length(src_tvb) - 1;/* don't include check byte */ + + guint8 *dst, *src, *buf_start, *buf_end, comp_flag_bits = 0; + guint16 data_offset, data_cnt; + guint8 src_buf[ MAX_WCP_BUF_LEN]; + tvbuff_t *tvb; + wcp_window_t *buf_ptr = 0; + wcp_pdata_t *pdata_ptr; + + buf_ptr = get_wcp_window_ptr(pinfo); + + buf_start = buf_ptr->buffer; + buf_end = buf_start + MAX_WIN_BUF_LEN; + + cd_item = proto_tree_add_item(tree, hf_wcp_compressed_data, + src_tvb, offset, cnt - offset, ENC_NA); + cd_tree = proto_item_add_subtree(cd_item, ett_wcp_comp_data); + if (cnt - offset > MAX_WCP_BUF_LEN) { + expert_add_info_format(pinfo, cd_item, &ei_wcp_compressed_data_exceeds, + "Compressed data exceeds maximum buffer length (%d > %d)", + cnt - offset, MAX_WCP_BUF_LEN); + return NULL; + } + + /* + * XXX - this will throw an exception if a snapshot length cut short + * the data. We may want to try to dissect the data in that case, + * and we may even want to try to decompress it, *but* we will + * want to mark the buffer of decompressed data as incomplete, so + * that we don't try to use it for decompressing later packets. + */ + src = (guint8 *)tvb_memcpy(src_tvb, src_buf, offset, cnt - offset); + dst = buf_ptr->buf_cur; + len = 0; + i = -1; + + while(offset < cnt) { + /* There are i bytes left for this byte of flag bits */ + if ( --i >= 0) { + /* + * There's still at least one more byte left for + * the current set of compression flag bits; is + * it compressed data or uncompressed data? + */ + if (comp_flag_bits & 0x80) { + /* This byte is compressed data */ + if (!(offset + 1 < cnt)) { + /* + * The data offset runs past the + * end of the data. + */ + return NULL; + } + data_offset = pntoh16(src) & WCP_OFFSET_MASK; + if ((*src & 0xf0) == 0x10) { + /* + * The count of bytes to copy from + * the dictionary window is in the + * byte following the data offset. + */ + if (!(offset + 2 < cnt)) { + /* + * The data count runs past the + * end of the data. + */ + return NULL; + } + data_cnt = *(src + 2) + 1; + if (tree) { + ti = proto_tree_add_item(cd_tree, hf_wcp_long_run, src_tvb, + offset, 3, ENC_NA); + sub_tree = proto_item_add_subtree(ti, ett_wcp_field); + proto_tree_add_uint(sub_tree, hf_wcp_offset, src_tvb, + offset, 2, data_offset); + + proto_tree_add_item(sub_tree, hf_wcp_long_len, src_tvb, + offset+2, 1, ENC_BIG_ENDIAN); + } + src += 3; + offset += 3; + } else { + /* + * The count of bytes to copy from + * the dictionary window is in + * the upper 4 bits of the next + * byte. + */ + data_cnt = (*src >> 4) + 1; + if (tree) { + ti = proto_tree_add_item(cd_tree, hf_wcp_short_run, src_tvb, + offset, 2, ENC_NA); + sub_tree = proto_item_add_subtree(ti, ett_wcp_field); + proto_tree_add_uint(sub_tree, hf_wcp_short_len, src_tvb, + offset, 1, *src); + proto_tree_add_uint(sub_tree, hf_wcp_offset, src_tvb, + offset, 2, data_offset); + } + src += 2; + offset += 2; + } + if (data_offset + 1 > buf_ptr->initialized) { + expert_add_info_format(pinfo, cd_item, &ei_wcp_invalid_window_offset, + "Data offset exceeds valid window size (%d > %d)", + data_offset+1, buf_ptr->initialized); + return NULL; + } + + if (data_offset + 1 < data_cnt) { + expert_add_info_format(pinfo, cd_item, &ei_wcp_invalid_window_offset, + "Data count exceeds offset (%d > %d)", + data_cnt, data_offset+1); + return NULL; + } + if ( !pinfo->fd->visited) { /* if first pass */ + dst = decompressed_entry(dst, + data_offset, data_cnt, &len, + buf_ptr); + if (dst == NULL) { + expert_add_info_format(pinfo, cd_item, &ei_wcp_uncompressed_data_exceeds, + "Uncompressed data exceeds maximum buffer length (%d > %d)", + len, MAX_WCP_BUF_LEN); + return NULL; + } + } + }else { + /* + * This byte is uncompressed data; is there + * room for it in the buffer of uncompressed + * data? + */ + if ( ++len >MAX_WCP_BUF_LEN) { + /* No - report an error. */ + expert_add_info_format(pinfo, cd_item, &ei_wcp_uncompressed_data_exceeds, + "Uncompressed data exceeds maximum buffer length (%d > %d)", + len, MAX_WCP_BUF_LEN); + return NULL; + } + + if ( !pinfo->fd->visited) { + /* + * This is the first pass through + * the packets, so copy it to the + * buffer of uncompressed data. + */ + *dst = *src; + if (dst++ == buf_end) + dst = buf_start; + if (buf_ptr->initialized < MAX_WIN_BUF_LEN) + buf_ptr->initialized++; + } + ++src; + ++offset; + } + + /* Skip to the next compression flag bit */ + comp_flag_bits <<= 1; + + }else { + /* + * There are no more bytes left for the current + * set of compression flag bits, so this byte + * is another byte of compression flag bits. + */ + comp_flag_bits = *src++; + proto_tree_add_uint(cd_tree, hf_wcp_comp_bits, src_tvb, offset, 1, + comp_flag_bits); + offset++; + + i = 8; + } + } + + if (pinfo->fd->visited) { /* if not first pass */ + /* get uncompressed data */ + pdata_ptr = (wcp_pdata_t *)p_get_proto_data(wmem_file_scope(), pinfo, proto_wcp, 0); + + if (!pdata_ptr) { /* exit if no data */ + REPORT_DISSECTOR_BUG("Can't find uncompressed data"); + return NULL; + } + len = pdata_ptr->len; + } else { + if (buf_ptr->buf_cur + len > buf_end) { + expert_add_info_format(pinfo, cd_item, &ei_wcp_invalid_window_offset, + "Uncompressed data exceeds available buffer length (%d > %d)", + len, (int) (buf_end - buf_ptr->buf_cur)); + return NULL; + } + + /* save the new data as per packet data */ + pdata_ptr = wmem_new0(wmem_file_scope(), wcp_pdata_t); + memcpy( &pdata_ptr->buffer, buf_ptr->buf_cur, len); + pdata_ptr->len = len; + + p_add_proto_data(wmem_file_scope(), pinfo, proto_wcp, 0, (void*)pdata_ptr); + + buf_ptr->buf_cur = dst; + } + + tvb = tvb_new_child_real_data(src_tvb, pdata_ptr->buffer, pdata_ptr->len, pdata_ptr->len); + + /* 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, + NULL, HFILL }}, + { &hf_wcp_rev, + { "Revision", "wcp.rev", FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL }}, + { &hf_wcp_init, + { "Initiator", "wcp.init", FT_UINT8, BASE_DEC, NULL, 0, + NULL, 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 }}, +#if 0 + { &hf_wcp_rexmit, + { "Rexmit", "wcp.rexmit", FT_UINT8, BASE_DEC, NULL, 0, + "Retransmit", HFILL }}, +#endif + { &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, + NULL, HFILL }}, + { &hf_wcp_compressed_data, + { "Compressed Data", "wcp.compressed_data", FT_NONE, BASE_NONE, NULL, 0, + "Raw compressed data", HFILL }}, + { &hf_wcp_comp_bits, + { "Compress Flag", "wcp.flag", FT_UINT8, BASE_HEX, NULL, 0, + "Compressed byte flag", HFILL }}, +#if 0 + { &hf_wcp_comp_marker, + { "Compress Marker", "wcp.mark", FT_UINT8, BASE_DEC, NULL, 0, + "Compressed marker", HFILL }}, +#endif + { &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_BYTES, BASE_NONE, NULL, 0, + "Long Compression type", HFILL }}, + { &hf_wcp_short_run, + { "Short Compression", "wcp.short_comp", FT_BYTES, BASE_NONE, NULL, 0, + "Short Compression type", HFILL }}, + + }; + + + static gint *ett[] = { + &ett_wcp, + &ett_wcp_comp_data, + &ett_wcp_field, + }; + + static ei_register_info ei[] = { + { &ei_wcp_compressed_data_exceeds, { "wcp.compressed_data.exceeds", PI_MALFORMED, PI_ERROR, "Compressed data exceeds maximum buffer length", EXPFILL }}, + { &ei_wcp_uncompressed_data_exceeds, { "wcp.uncompressed_data.exceeds", PI_MALFORMED, PI_ERROR, "Uncompressed data exceeds maximum buffer length", EXPFILL }}, + { &ei_wcp_invalid_window_offset, { "wcp.off.invalid", PI_MALFORMED, PI_ERROR, "Offset points outside of visible window", EXPFILL }}, + { &ei_wcp_buffer_too_long, { "wcp.buffer_too_long", PI_MALFORMED, PI_ERROR, "Buffer too long", EXPFILL }}, +#if 0 + { &ei_wcp_invalid_match_length, { "wcp.len.invalid", PI_MALFORMED, PI_ERROR, "Length greater than offset", EXPFILL }}, +#endif + }; + + expert_module_t* expert_wcp; + + 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)); + expert_wcp = expert_register_protocol(proto_wcp); + expert_register_field_array(expert_wcp, ei, array_length(ei)); + wcp_handle = register_dissector("wcp", dissect_wcp, proto_wcp); +} + + +void +proto_reg_handoff_wcp(void) { + /* + * Get handle for the Frame Relay (uncompressed) dissector. + */ + fr_uncompressed_handle = find_dissector_add_dependency("fr_uncompressed", proto_wcp); + + dissector_add_uint("fr.nlpid", NLPID_COMPRESSED, wcp_handle); + dissector_add_uint("ethertype", ETHERTYPE_WCP, wcp_handle); +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 8 + * tab-width: 8 + * indent-tabs-mode: t + * End: + * + * vi: set shiftwidth=8 tabstop=8 noexpandtab: + * :indentSize=8:tabSize=8:noTabs=false: + */ |