diff options
Diffstat (limited to 'epan/dissectors/packet-x29.c')
-rw-r--r-- | epan/dissectors/packet-x29.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/epan/dissectors/packet-x29.c b/epan/dissectors/packet-x29.c new file mode 100644 index 0000000000..5d7b937b47 --- /dev/null +++ b/epan/dissectors/packet-x29.c @@ -0,0 +1,281 @@ +/* packet-x29.c + * Routines for X.29 packet dissection + * + * $Id$ + * + * Ethereal - Network traffic analyzer + * By Gerald Combs <gerald@ethereal.com> + * Copyright 1998 Gerald Combs + * + * 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. + */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <stdio.h> + +#include <string.h> +#include <glib.h> +#include <epan/packet.h> +#include <epan/strutil.h> +#include "nlpid.h" + +static int proto_x29 = -1; +static int hf_msg_code = -1; +static int hf_error_type = -1; +static int hf_inv_msg_code = -1; + +static gint ett_x29 = -1; + +/* + * PAD messages. + */ +#define SET_MSG 0x02 +#define READ_MSG 0x04 +#define SET_AND_READ_MSG 0x06 +#define PARAMETER_IND_MSG 0x00 +#define INV_TO_CLEAR_MSG 0x01 +#define BREAK_IND_MSG 0x03 +#define RESELECTION_MSG 0x07 +#define ERROR_MSG 0x05 +#define RESEL_WITH_TOA_NPI_MSG 0x08 + +static const value_string message_code_vals[] = { + { SET_MSG, "Set" }, + { READ_MSG, "Read" }, + { SET_AND_READ_MSG, "Set and read" }, + { PARAMETER_IND_MSG, "Parameter indication" }, + { INV_TO_CLEAR_MSG, "Invitation to clear" }, + { BREAK_IND_MSG, "Indication of break" }, + { RESELECTION_MSG, "Reselection" }, + { ERROR_MSG, "Error" }, + { RESEL_WITH_TOA_NPI_MSG, "Reselection with TOA/NPI" }, + { 0, NULL } +}; + +static const value_string error_type_vals[] = { + { 0x00, "Received PAD message contained less than eight bits" }, + { 0x02, "Unrecognized message code in received PAD message" }, + { 0x04, "Parameter field format was incorrect or incompatible with message code" }, + { 0x06, "Received PAD message did not contain an integral number of octets" }, + { 0x08, "Received Parameter Indication PAD message was unsolicited" }, + { 0x0A, "Received PAD message was too long" }, + { 0x0C, "Unauthorized reselection PAD message" }, + { 0, NULL }, +}; + +static void +dissect_x29(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + int offset = 0; + proto_tree *x29_tree = NULL; + proto_item *ti; + gboolean *q_bit_set = pinfo->private_data; + guint8 msg_code; + guint8 error_type; + guint8 type_ref; + gint next_offset; + int linelen; + + if (check_col(pinfo->cinfo, COL_PROTOCOL)) + col_set_str(pinfo->cinfo, COL_PROTOCOL, "X.29"); + if (check_col(pinfo->cinfo, COL_INFO)) + col_clear(pinfo->cinfo, COL_INFO); + + if (tree) { + ti = proto_tree_add_item(tree, proto_x29, tvb, offset, -1, + FALSE); + x29_tree = proto_item_add_subtree(ti, ett_x29); + } + + if (*q_bit_set) { + /* + * Q bit set - this is a PAD message. + */ + msg_code = tvb_get_guint8(tvb, offset); + if (check_col(pinfo->cinfo, COL_INFO)) { + col_add_fstr(pinfo->cinfo, COL_INFO, "%s PAD message", + val_to_str(msg_code, message_code_vals, + "Unknown (0x%02x)")); + } + proto_tree_add_uint(x29_tree, hf_msg_code, tvb, + offset, 1, msg_code); + offset++; + + switch (msg_code) { + + case SET_MSG: + case READ_MSG: + case SET_AND_READ_MSG: + case PARAMETER_IND_MSG: + /* + * XXX - dissect the references as per X.3. + */ + while (tvb_reported_length_remaining(tvb, offset) > 0) { + proto_tree_add_text(x29_tree, tvb, offset, 2, + "Parameter %u, value %u", + tvb_get_guint8(tvb, offset), + tvb_get_guint8(tvb, offset + 1)); + offset += 2; + } + break; + + case INV_TO_CLEAR_MSG: + /* + * No data for this message. + */ + break; + + case ERROR_MSG: + error_type = tvb_get_guint8(tvb, offset); + proto_tree_add_uint(x29_tree, hf_error_type, tvb, + offset, 1, error_type); + offset++; + if (error_type != 0) { + proto_tree_add_item(x29_tree, hf_inv_msg_code, + tvb, offset, 1, FALSE); + } + break; + + case BREAK_IND_MSG: + if (tvb_reported_length_remaining(tvb, offset) > 0) { + type_ref = tvb_get_guint8(tvb, offset); + switch (type_ref) { + + case 0x01: /* change in PAD Aspect */ + /* + * XXX - dissect as per X.28. + */ + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Type reference: Change in PAD Aspect"); + offset++; + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Type of aspect: 0x%02x", + type_ref); + offset++; + break; + + case 0x08: /* break */ + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Type reference: Break"); + offset++; + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Break value: 0x%02x", + type_ref); + offset++; + break; + + default: + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Unknown type reference (0x%02x)", + type_ref); + offset++; + proto_tree_add_text(x29_tree, tvb, + offset, 1, "Type value: 0x%02x", + type_ref); + offset++; + break; + } + } + break; + + case RESELECTION_MSG: + /* + * XXX - dissect me. + */ + proto_tree_add_text(x29_tree, tvb, offset, -1, + "Reselection message data"); + break; + + case RESEL_WITH_TOA_NPI_MSG: + /* + * XXX - dissect me. + */ + proto_tree_add_text(x29_tree, tvb, offset, -1, + "Reselection message data"); + break; + + default: + proto_tree_add_text(x29_tree, tvb, offset, -1, + "PAD message data"); + break; + } + } else { + /* + * Q bit not set - this is data. + */ + if (check_col(pinfo->cinfo, COL_INFO)) + col_add_fstr(pinfo->cinfo, COL_INFO, "Data ..."); + + if (tree) { + while (tvb_offset_exists(tvb, offset)) { + /* + * Find the end of the line. + */ + linelen = tvb_find_line_end(tvb, offset, -1, + &next_offset, FALSE); + + /* + * Now compute the length of the line + * *including* the end-of-line indication, + * if any; we display it all. + */ + linelen = next_offset - offset; + + proto_tree_add_text(x29_tree, tvb, offset, + linelen, "Data: %s", + tvb_format_text(tvb, offset, linelen)); + offset = next_offset; + } + } + } +} + +void +proto_register_x29(void) +{ + static hf_register_info hf[] = { + { &hf_msg_code, + { "Message code", "x29.msg_code", FT_UINT8, BASE_HEX, + VALS(message_code_vals), 0x0, "X.29 PAD message code", + HFILL }}, + { &hf_error_type, + { "Error type", "x29.error_type", FT_UINT8, BASE_HEX, + VALS(error_type_vals), 0x0, "X.29 error PAD message error type", + HFILL }}, + { &hf_inv_msg_code, + { "Invalid message code", "x29.inv_msg_code", FT_UINT8, BASE_HEX, + VALS(message_code_vals), 0x0, "X.29 Error PAD message invalid message code", + HFILL }}, + }; + static gint *ett[] = { + &ett_x29, + }; + + proto_x29 = proto_register_protocol("X.29", "X.29", "x.29"); + proto_register_field_array(proto_x29, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); +} + +void +proto_reg_handoff_x29(void) +{ + dissector_handle_t x29_handle; + + x29_handle = create_dissector_handle(dissect_x29, proto_x29); + dissector_add("x.25.spi", NLPID_SPI_X_29, x29_handle); +} |