/* packet-esis.c * Routines for ISO/OSI End System to Intermediate System * Routing Exchange Protocol ISO 9542. * * $Id$ * Ralf Schneider * * Ethereal - Network traffic analyzer * By Gerald Combs * 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 #include #include #include #include "nlpid.h" #include "packet-osi.h" #include "packet-osi-options.h" #include "packet-esis.h" /* esis base header */ static int proto_esis = -1; static int hf_esis_nlpi = -1; static int hf_esis_length = -1; static int hf_esis_version = -1; static int hf_esis_reserved = -1; static int hf_esis_type = -1; static int hf_esis_holdtime = -1; static int hf_esis_checksum = -1; static gint ett_esis = -1; static gint ett_esis_area_addr = -1; static const value_string esis_vals[] = { { ESIS_ESH_PDU, "ES HELLO"}, { ESIS_ISH_PDU, "IS HELLO"}, { ESIS_RD_PDU, "RD REQUEST"}, { 0, NULL} }; /* internal prototypes */ static void esis_dissect_esh_pdu( guint8 len, tvbuff_t *tvb, proto_tree *treepd); static void esis_dissect_ish_pdu( guint8 len, tvbuff_t *tvb, proto_tree *tree); static void esis_dissect_redirect_pdu( guint8 len, tvbuff_t *tvb, proto_tree *tree); /* ################## Descriptions ###########################################*/ /* Parameters for the ESH PDU * Source Address Parameter: * * Octet: Length: Parameter Type: * 10 1 Number of Source Adresses ( NSAPs served by this Network * 11 1 Source Address Length Indicator ( SAL ) # Entity ) * 12-m-1 variable Source Address ( NSAP ) * m Options, dissected in osi.c * * * Parameter for the ISH PDU: * Network Entity Title Parameter: * * Octet: Length: Parameter Type: * 10 1 Network Entity Title Length Indicator ( NETL ) * 11-m-1 variable Network Entity Title ( NET ) * m Options, dissected in osi.c * * * Parameter for the RD PDU: * When re-directed to an IS: * * Octet: Length: Parameter Type: * 10 1 Destination Address Length Indicator ( DAL ) * 11>m-1 variable Destination Address ( DA ) * m 1 Subnetwork Address Length Indicator ( BSNPAL ) * m+1>n-1 variable Subnetwork Address ( BSNPA ) * n 1 Network Entity Title Length Indicator ( NETL ) * n+1>p-1 variable Network Entity Title ( NET ) * p Options, dissected in osi.c * * * Parameter for the RD PDU: * When re-directed to an ES: * * Octet: Length: Parameter Type: * 10 1 Destination Address Length Indicator ( DAL ) * 11>m-1 variable Destination Address ( DA ) * m 1 Subnetwork Address Length Indicator ( BSNPAL ) * m+1>n-1 variable Subnetwork Address ( BSNPA ) * n 1 Network Entity Title Length Indicator ( NETL ) == 0 * n+1 Options, dissected in osi.c * */ /* ############################ Tool Functions ############################## */ /* ############################## Dissection Functions ###################### */ /* * Name: dissect_esis_unknown() * * Description: * There was some error in the protocol and we are in unknown space * here. Add a tree item to cover the error and go on. Note * that we make sure we don't go off the end of the bleedin packet here! * * This is just a copy of isis.c and isis.h, so I keep the stuff also * and adapt the names to cover possible protocol errors! Ive really no * idea wether I need this or not. * * Input * tvbuff_t * : tvbuff with packet data. * proto_tree * : tree of display data. May be NULL. * char * : format text * subsequent args : arguments to format * * Output: * void (may modify proto tree) */ static void esis_dissect_unknown( tvbuff_t *tvb, proto_tree *tree, char *fmat, ...){ va_list ap; va_start(ap, fmat); proto_tree_add_text_valist(tree, tvb, 0, -1, fmat, ap); va_end(ap); } static void esis_dissect_esh_pdu( guint8 len, tvbuff_t *tvb, proto_tree *tree) { proto_tree *esis_area_tree; int offset = 0; int no_sa = 0; int sal = 0; proto_item *ti; if (tree) { offset += ESIS_HDR_FIXED_LENGTH; no_sa = tvb_get_guint8(tvb, offset); len -= 1; ti = proto_tree_add_text( tree, tvb, offset, -1, "Number of Source Addresses (SA, Format: NSAP) : %u", no_sa ); offset++; esis_area_tree = proto_item_add_subtree( ti, ett_esis_area_addr ); while ( no_sa-- > 0 ) { sal = (int) tvb_get_guint8(tvb, offset); offset++; proto_tree_add_text(esis_area_tree, tvb, offset, 1, "SAL: %2u Octets", sal); proto_tree_add_text(esis_area_tree, tvb, offset + 1, sal, " SA: %s", print_nsap_net( tvb_get_ptr(tvb, offset, sal), sal ) ); offset += sal; len -= ( sal + 1 ); } dissect_osi_options( len, tvb, offset, tree ); } } /* esis_dissect_esh_pdu */ static void esis_dissect_ish_pdu( guint8 len, tvbuff_t *tvb, proto_tree *tree) { int offset = 0; int netl = 0; if (tree) { offset += ESIS_HDR_FIXED_LENGTH; netl = (int) tvb_get_guint8(tvb, offset); proto_tree_add_text( tree, tvb, offset, netl + 1, "### Network Entity Title Section ###"); proto_tree_add_text( tree, tvb, offset++, 1, "NETL: %2u Octets", netl); proto_tree_add_text( tree, tvb, offset, netl, " NET: %s", print_nsap_net( tvb_get_ptr(tvb, offset, netl), netl ) ); offset += netl; len -= ( netl + 1 ); dissect_osi_options( len, tvb, offset, tree ); } } static void esis_dissect_redirect_pdu( guint8 len, tvbuff_t *tvb, proto_tree *tree) { int offset = 0; int tmpl = 0; if (tree) { offset += ESIS_HDR_FIXED_LENGTH; tmpl = (int) tvb_get_guint8(tvb, offset); proto_tree_add_text( tree, tvb, offset, tmpl + 1, "### Destination Address Section ###" ); proto_tree_add_text( tree, tvb, offset++, 1, "DAL: %2u Octets", tmpl); proto_tree_add_text( tree, tvb, offset, tmpl, " DA : %s", print_nsap_net( tvb_get_ptr(tvb, offset, tmpl), tmpl ) ); offset += tmpl; len -= ( tmpl + 1 ); tmpl = (int) tvb_get_guint8(tvb, offset); proto_tree_add_text( tree, tvb, offset, tmpl + 1, "### Subnetwork Address Section ###"); proto_tree_add_text( tree, tvb, offset++, 1, "BSNPAL: %2u Octets", tmpl); proto_tree_add_text( tree, tvb, offset, tmpl, " BSNPA: %s", print_system_id( tvb_get_ptr(tvb, offset, tmpl), tmpl ) ); offset += tmpl; len -= ( tmpl + 1 ); tmpl = (int) tvb_get_guint8(tvb, offset); if ( 0 == tmpl ) { proto_tree_add_text( tree, tvb, offset, 1, "### No Network Entity Title Section ###" ); offset++; len--; } else { proto_tree_add_text( tree, tvb, offset, 1, "### Network Entity Title Section ###" ); proto_tree_add_text( tree, tvb, offset++, 1, "NETL: %2u Octets", tmpl ); proto_tree_add_text( tree, tvb, offset, tmpl, " NET: %s", print_nsap_net( tvb_get_ptr(tvb, offset, tmpl), tmpl ) ); offset += tmpl; len -= ( tmpl + 1 ); } dissect_osi_options( len, tvb, offset, tree ); } } /* * Name: dissect_esis() * * Description: * Main entry area for esis de-mangling. This will build the * main esis tree data and call the sub-protocols as needed. * * Input: * tvbuff * : tvbuff referring to packet data * packet_info * : info for current packet * proto_tree * : tree of display data. May be NULL. * * Output: * void, but we will add to the proto_tree if it is not NULL. */ static void dissect_esis(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { char *pdu_type_string = NULL; char *pdu_type_format_string = "PDU Type : %s (R:%s%s%s)"; esis_hdr_t ehdr; proto_item *ti; proto_tree *esis_tree = NULL; guint8 variable_len; guint tmp_uint = 0; char *cksum_status; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "ESIS"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); tvb_memcpy(tvb, (guint8 *)&ehdr, 0, sizeof ehdr); if (tree) { ti = proto_tree_add_item(tree, proto_esis, tvb, 0, -1, FALSE); esis_tree = proto_item_add_subtree(ti, ett_esis); if (ehdr.esis_version != ESIS_REQUIRED_VERSION){ esis_dissect_unknown(tvb, esis_tree, "Unknown ESIS version (%u vs %u)", ehdr.esis_version, ESIS_REQUIRED_VERSION ); return; } if (ehdr.esis_length < ESIS_HDR_FIXED_LENGTH) { esis_dissect_unknown(tvb, esis_tree, "Bogus ESIS length (%u, must be >= %u)", ehdr.esis_length, ESIS_HDR_FIXED_LENGTH ); return; } proto_tree_add_uint( esis_tree, hf_esis_nlpi, tvb, 0, 1, ehdr.esis_nlpi ); proto_tree_add_uint( esis_tree, hf_esis_length, tvb, 1, 1, ehdr.esis_length ); proto_tree_add_uint( esis_tree, hf_esis_version, tvb, 2, 1, ehdr.esis_version ); proto_tree_add_uint( esis_tree, hf_esis_reserved, tvb, 3, 1, ehdr.esis_reserved ); pdu_type_string = val_to_str(ehdr.esis_type&OSI_PDU_TYPE_MASK, esis_vals, "Unknown (0x%x)"); proto_tree_add_uint_format( esis_tree, hf_esis_type, tvb, 4, 1, ehdr.esis_type, pdu_type_format_string, pdu_type_string, (ehdr.esis_type&BIT_8) ? "1" : "0", (ehdr.esis_type&BIT_7) ? "1" : "0", (ehdr.esis_type&BIT_6) ? "1" : "0"); tmp_uint = pntohs( ehdr.esis_holdtime ); proto_tree_add_uint_format(esis_tree, hf_esis_holdtime, tvb, 5, 2, tmp_uint, "Holding Time : %u seconds", tmp_uint ); tmp_uint = pntohs( ehdr.esis_checksum ); switch (calc_checksum( tvb, 0, ehdr.esis_length, tmp_uint )) { case NO_CKSUM: cksum_status = "Not Used"; break; case DATA_MISSING: cksum_status = "Not checkable - not all of packet was captured"; break; case CKSUM_OK: cksum_status = "Is good"; break; case CKSUM_NOT_OK: cksum_status = "Is wrong"; break; default: cksum_status = NULL; g_assert_not_reached(); } proto_tree_add_uint_format( esis_tree, hf_esis_checksum, tvb, 7, 2, tmp_uint, "Checksum : 0x%x ( %s )", tmp_uint, cksum_status ); } /* * Let us make sure we use the same names for all our decodes * here. First, dump the name into info column, and THEN * dispatch the sub-type. */ if (check_col(pinfo->cinfo, COL_INFO)) { col_add_str(pinfo->cinfo, COL_INFO, val_to_str( ehdr.esis_type&OSI_PDU_TYPE_MASK, esis_vals, "Unknown (0x%x)" ) ); } variable_len = ehdr.esis_length - ESIS_HDR_FIXED_LENGTH; switch (ehdr.esis_type & OSI_PDU_TYPE_MASK) { case ESIS_ESH_PDU: esis_dissect_esh_pdu( variable_len, tvb, esis_tree); break; case ESIS_ISH_PDU: esis_dissect_ish_pdu( variable_len, tvb, esis_tree); break; case ESIS_RD_PDU: esis_dissect_redirect_pdu( variable_len, tvb, esis_tree); break; default: esis_dissect_unknown(tvb, esis_tree, "Unknown ESIS packet type 0x%x", ehdr.esis_type & OSI_PDU_TYPE_MASK ); } } /* dissect_esis */ /* * Name: proto_register_esis() * * Description: * main register for esis protocol set. We register some display * formats and the protocol module variables. * * NOTE: this procedure to autolinked by the makefile process that * builds register.c * * Input: * void * * Output: * void */ void proto_register_esis(void) { static hf_register_info hf[] = { { &hf_esis_nlpi, { "Network Layer Protocol Identifier", "esis.nlpi", FT_UINT8, BASE_HEX, VALS(nlpid_vals), 0x0, "", HFILL }}, { &hf_esis_length, { "PDU Length ", "esis.length", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_esis_version, { "Version (==1) ", "esis.ver", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_esis_reserved, { "Reserved(==0) ", "esis.res", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_esis_type, { "PDU Type ", "esis.type", FT_UINT8, BASE_DEC, VALS(esis_vals), 0xff, "", HFILL }}, { &hf_esis_holdtime, { "Holding Time ", "esis.htime", FT_UINT16, BASE_DEC, NULL, 0x0, " s", HFILL }}, { &hf_esis_checksum, { "Checksum ", "esis.chksum", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL }} }; /* * * */ static gint *ett[] = { &ett_esis, &ett_esis_area_addr, }; proto_esis = proto_register_protocol( PROTO_STRING_ESIS, "ESIS", "esis"); proto_register_field_array(proto_esis, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); } void proto_reg_handoff_esis(void) { dissector_handle_t esis_handle; esis_handle = create_dissector_handle(dissect_esis, proto_esis); register_dissector("esis", dissect_esis, proto_esis); dissector_add("osinl", NLPID_ISO9542_ESIS, esis_handle); }