/* packet-gprs-ns.c * Routines for GPRS Network Service (ETSI GSM 08.16 version 6.3.0) * dissection * Copyright 2003, Josef Korelus * * $Id: packet-gprs-ns.c,v 1.7 2003/11/14 18:59:00 guy Exp $ * * 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 /*ETSI GSM08.16 Network Service */ #define NS_UNITDATA 0x00 #define NS_RESET 0x02 #define NS_RESET_ACK 0x03 #define NS_BLOCK 0x04 #define NS_BLOCK_ACK 0x05 #define NS_UNBLOCK 0x06 #define NS_UNBLOCK_ACK 0x07 #define NS_STATUS 0x08 #define NS_ALIVE 0x0a #define NS_ALIVE_ACK 0x0b /*ETSI GSM 08.16 IEI coding */ #define Cause 0x00 #define NS_VCI 0x01 #define NS_PDU 0x02 #define BVCI 0x03 #define NSEI 0x04 static int proto_gprs_ns = -1; static gint ett_gprs_ns = -1; static int hf_gprs_ns_pdutype = -1; static int hf_gprs_ns_ie_type = -1; static int hf_gprs_ns_ie_length = -1; static int hf_gprs_ns_cause = -1; static int hf_gprs_ns_vci = -1; static int hf_gprs_ns_nsei = -1; static int hf_gprs_ns_bvci = -1; static int hf_gprs_ns_spare = -1; static const value_string ns_pdu_type[]= { { NS_UNITDATA, "NS-UNITDATA" }, { NS_RESET, "NS-RESET" }, { NS_RESET_ACK, "NS-RESET-ACK" }, { NS_BLOCK, "NS-BLOCK" }, { NS_BLOCK_ACK, "NS-BLOCK-ACK" }, { NS_UNBLOCK, "NS-UNBLOCK" }, { NS_UNBLOCK_ACK, "NS-UNBLOCK-ACK" }, { NS_STATUS, "NS-STATUS" }, { NS_ALIVE, "NS-ALIVE" }, { NS_ALIVE_ACK, "NS-ALIVE-ACK" }, { 0, NULL }, }; static const value_string ns_ie_type[]= { { Cause, "Cause" }, { NS_VCI, "NS-VCI"}, { NS_PDU, "NS PDU"}, { BVCI, "BVCI"}, { NSEI, "NSEI"}, { 0, NULL }, }; static const value_string cause_val[]= { { 0x0, "Transit network failure" }, { 0x1, "O&M intervention" }, { 0x2, "Equipment failure" }, { 0x3, "NS-VC blocked " }, { 0x4, "NS-VC unknown" }, { 0x5, "NS-VC unknown on that NSE" }, { 0x8, "Semantically incorrect PDU" }, { 0xa, "PDU not compatible with protocol state" }, { 0xb, "Protocol error - unspecified" }, { 0xc, "Invalid essential IE" }, { 0xd, "Missing essential IE" }, { 0, NULL }, }; static dissector_handle_t bssgp_handle; static void process_tlvs(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree) { guint8 type; int length_len; guint16 length; guint8 cause; guint16 nsvc, bvc, nsei; while (tvb_reported_length_remaining(tvb, offset) > 0) { type = tvb_get_guint8(tvb, offset); proto_tree_add_uint(tree, hf_gprs_ns_ie_type, tvb, offset, 1, type); offset++; length_len = 1; length = tvb_get_guint8(tvb, offset); if (length & 0x80) { /* * This is the final octet of the length. */ length &= 0x7F; } else { /* * One more octet. */ length_len++; length = (length << 8) | tvb_get_guint8(tvb, offset); } proto_tree_add_uint(tree, hf_gprs_ns_ie_length, tvb, offset, length_len, length); offset += length_len; switch (type) { case Cause: if (length == 1) { cause = tvb_get_guint8(tvb, offset); if (tree) { proto_tree_add_uint(tree, hf_gprs_ns_cause, tvb, offset, 1, cause); } if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, " Cause: %s", val_to_str(cause, cause_val, "Unknown (0x%02x)")); } } else { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Bad cause length %u, should be 1\n", length); } } break; case NS_VCI: if (length == 2) { nsvc = tvb_get_ntohs(tvb, offset); if (tree) { proto_tree_add_uint(tree, hf_gprs_ns_vci, tvb, offset, 2, nsvc); } if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, " NSVCI: %u", nsvc); } } else { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Bad NS-VCI length %u, should be 2\n", length); } } break; case NS_PDU: /* * XXX - dissect as a GPRS NS PDU. * Do the usual "error packet" stuff. */ if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Error PDU"); } break; case BVCI: if (length == 2) { bvc = tvb_get_ntohs(tvb, offset); if (tree) { proto_tree_add_uint(tree, hf_gprs_ns_bvci, tvb, offset, 2, bvc); } if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, " BVCI: %u", bvc); } } else { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Bad BVCI length %u, should be 2\n", length); } } break; case NSEI: if (length == 2) { nsei = tvb_get_ntohs(tvb, offset); if (tree) { proto_tree_add_uint(tree, hf_gprs_ns_nsei, tvb, offset, 2, nsei); } if (check_col(pinfo->cinfo, COL_INFO)) { col_append_fstr(pinfo->cinfo, COL_INFO, " NSEI: %u", nsei); } } else { if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Bad NSEI length %u, should be 2\n", length); } } break; default: if (tree) { proto_tree_add_text(tree, tvb, offset, length, "Unknown IE contents"); } break; } offset += length; } } static void dissect_gprs_ns(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { int offset = 0; proto_item *ti = NULL; proto_tree *gprs_ns_tree = NULL; guint8 nspdu; guint16 bvc; tvbuff_t *next_tvb; if (check_col(pinfo->cinfo, COL_PROTOCOL)) col_set_str(pinfo->cinfo, COL_PROTOCOL, "GPRS NS"); if (check_col(pinfo->cinfo, COL_INFO)) col_clear(pinfo->cinfo, COL_INFO); nspdu = tvb_get_guint8(tvb,offset); if (check_col(pinfo->cinfo, COL_INFO)) { col_add_str(pinfo->cinfo, COL_INFO, val_to_str(nspdu, ns_pdu_type, "Unknown PDU type (0x%02x)")); } if (tree) { ti = proto_tree_add_item(tree, proto_gprs_ns, tvb, 0, -1, FALSE); gprs_ns_tree = proto_item_add_subtree(ti, ett_gprs_ns); proto_tree_add_uint(gprs_ns_tree, hf_gprs_ns_pdutype, tvb, 0, 1, nspdu); } offset++; switch (nspdu) { case NS_ALIVE: case NS_ALIVE_ACK: case NS_UNBLOCK: case NS_UNBLOCK_ACK: break; case NS_BLOCK: case NS_BLOCK_ACK: case NS_RESET: case NS_RESET_ACK: case NS_STATUS: /* * Process TLVs. */ process_tlvs(tvb, offset, pinfo, gprs_ns_tree); break; case NS_UNITDATA: if (tree) proto_tree_add_item(gprs_ns_tree, hf_gprs_ns_spare, tvb, offset, 1, FALSE); offset++; bvc = tvb_get_ntohs(tvb,offset); if (check_col(pinfo->cinfo, COL_INFO)) col_append_fstr(pinfo->cinfo, COL_INFO, " BVCI: %u", bvc); if (tree) proto_tree_add_uint(gprs_ns_tree, hf_gprs_ns_bvci, tvb, offset, 2, bvc); offset=offset+2; next_tvb = tvb_new_subset(tvb, offset, -1, -1); call_dissector(bssgp_handle, next_tvb, pinfo, tree); break; default: break; } } /* Register the protocol with Ethereal */ void proto_register_gprs_ns(void) { static hf_register_info hf[] = { { &hf_gprs_ns_pdutype, { "PDU Type", "gprs_ns.pdutype", FT_UINT8, BASE_HEX, VALS(ns_pdu_type), 0x0, "NS Command", HFILL}}, { &hf_gprs_ns_ie_type, { "IE Type", "gprs_ns.ietype", FT_UINT8, BASE_HEX, VALS(ns_ie_type), 0x0, "IE Type", HFILL}}, { &hf_gprs_ns_ie_length, { "IE Length", "gprs_ns.ielength", FT_UINT16, BASE_DEC, NULL, 0x0, "IE Length", HFILL}}, { &hf_gprs_ns_cause, { "Cause", "gprs_ns.cause", FT_UINT8, BASE_HEX, VALS(cause_val), 0x0, "Cause", HFILL}}, { &hf_gprs_ns_vci, { "NSVCI", "gprs_ns.nsvci", FT_UINT16, BASE_DEC, NULL, 0x0, "Network Service Virtual Connection id", HFILL}}, { &hf_gprs_ns_nsei, { "NSEI", "gprs_ns.nsei", FT_UINT16, BASE_DEC, NULL, 0x0, "Network Service Entity Id", HFILL}}, { &hf_gprs_ns_bvci, { "BVCI", "gprs_ns.bvci", FT_UINT16, BASE_DEC, NULL, 0x0, "Cell ID", HFILL}}, { &hf_gprs_ns_spare, { "Spare octet", "gprs_ns.spare", FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL}}, }; /* Setup protocol subtree array */ static gint *ett[] = { &ett_gprs_ns, }; proto_gprs_ns = proto_register_protocol("GPRS Network service", "GPRS NS","gprs_ns"); proto_register_field_array(proto_gprs_ns, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("gprs_ns", dissect_gprs_ns, proto_gprs_ns); } void proto_reg_handoff_gprs_ns(void) { bssgp_handle = find_dissector("bssgp"); }