Hi! I've written the following wireshark dissector for the GSM A-bis over IP protocol as it is used with ip.access nanoBTS products. The code was written while developing OpenBSC (see http://openbsc.gnumonks.org/).
I'd like to request its inclusion into the wireshark mainline tree. Please review and let me know if there are any issues. I'm also in the process of writing a generic GSM 12.21 (A-bis OML) dissector, as well as extending the packet-rsl.c with ip.access nanoBTS vendor extensions. I'm not sure when those will be finished, but I expect to post them within the next couple of weeks. Regards, Harald Index: epan/dissectors/Makefile.common =================================================================== --- epan/dissectors/Makefile.common.orig 2009-07-03 22:19:54.000000000 +0200 +++ epan/dissectors/Makefile.common 2009-07-03 22:20:16.000000000 +0200 @@ -471,6 +471,7 @@ packet-gsm_a_gm.c \ packet-gsm_a_rp.c \ packet-gsm_a_rr.c \ + packet-gsm_abis_ip.c \ packet-gsm_bsslap.c \ packet-gsm_bssmap_le.c \ packet-gsm_sms.c \ Index: epan/dissectors/packet-rsl.c =================================================================== --- epan/dissectors/packet-rsl.c.orig 2009-07-03 22:19:54.000000000 +0200 +++ epan/dissectors/packet-rsl.c 2009-07-03 22:20:16.000000000 +0200 @@ -3950,6 +3950,7 @@ proto_register_field_array(proto_rsl, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); + register_dissector("gsm_abis_rsl", dissect_rsl, proto_rsl); } Index: epan/dissectors/packet-gsm_abis_ip.c =================================================================== --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ epan/dissectors/packet-gsm_abis_ip.c 2009-07-03 22:20:16.000000000 +0200 @@ -0,0 +1,279 @@ +/* packet-gsm_abis_ip.c + * Routines for packet dissection of ip.access A-bis over IP + * Copyright 2009 by Harald Welte <lafo...@gnumonks.org> + * + * $Id$ + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <ger...@wireshark.org> + * 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 <glib.h> + +#include <epan/packet.h> +#include <epan/emem.h> + +/* Initialize the protocol and registered fields */ +static int proto_abisip = -1; +static int proto_ipaccess = -1; + +static int hf_abisip_data_len = -1; +static int hf_abisip_protocol = -1; + +static int hf_ipaccess_msgtype = -1; +static int hf_ipaccess_attr_tag = -1; +static int hf_ipaccess_attr_string = -1; + +/* Initialize the subtree pointers */ +static gint ett_abisip = -1; +static gint ett_ipaccess = -1; + +enum { + SUB_OML, + SUB_RSL, + SUB_IPACCESS, + + SUB_MAX +}; + +static dissector_handle_t sub_handles[SUB_MAX]; + +#define TCP_PORT_ABISIP_PRIM 3002 +#define TCP_PORT_ABISIP_SEC 3003 +#define TCP_PORT_ABISIP_INST 3006 + +#define ABISIP_RSL 0x00 +#define ABISIP_IPACCESS 0xfe +#define ABISIP_OML 0xff + +static const value_string abisip_protocol_vals[] = { + { 0x00, "RSL" }, + { 0xfe, "IPA" }, + { 0xff, "OML" }, + { 0, NULL } +}; + +static const value_string ipaccess_msgtype_vals[] = { + { 0x00, "PING?" }, + { 0x01, "PONG!" }, + { 0x04, "IDENTITY REQUEST" }, + { 0x05, "IDENTITY RESPONSE" }, + { 0x06, "IDENTITY CONF" }, + { 0, NULL } +}; + +static const value_string ipaccess_idtag_vals[] = { + { 0x00, "Serial Number" }, + { 0x01, "Unit Name" }, + { 0x02, "Location" }, + { 0x04, "Equipment Version" }, + { 0x05, "Software Version" }, + { 0x06, "IP Address" }, + { 0x07, "MAC Address" }, + { 0x08, "Unit ID" }, +}; + +static gint +dissect_ipa_attr(tvbuff_t *tvb, int base_offs, proto_tree *tree) +{ + guint8 len, tag, attr_type; + + int offset = base_offs; + + while (tvb_reported_length_remaining(tvb, offset) != 0) { + attr_type = tvb_get_guint8(tvb, offset); + + switch (attr_type) { + case 0x00: /* a string prefixed by its length */ + len = tvb_get_guint8(tvb, offset+1); + tag = tvb_get_guint8(tvb, offset+2); + proto_tree_add_item(tree, hf_ipaccess_attr_tag, + tvb, offset+2, 1, FALSE); + proto_tree_add_item(tree, hf_ipaccess_attr_string, + tvb, offset+3, len-1, FALSE); + break; + case 0x01: /* a single-byte reqest for a certain attr */ + len = 0; + proto_tree_add_item(tree, hf_ipaccess_attr_tag, + tvb, offset+1, 1, FALSE); + break; + }; + offset += len + 2; + }; + return offset; +} + +/* Dissect an ip.access specific message */ +static gint +dissect_ipaccess(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + proto_item *ti; + proto_tree *ipaccess_tree; + guint8 msg_type; + + msg_type = tvb_get_guint8(tvb, 0); + + if (check_col(pinfo->cinfo, COL_INFO)) + col_append_fstr(pinfo->cinfo, COL_INFO, "%s ", + val_to_str(msg_type, ipaccess_msgtype_vals, + "unknown 0x%02x")); + if (tree) { + ti = proto_tree_add_item(tree, proto_ipaccess, tvb, 0, -1, FALSE); + ipaccess_tree = proto_item_add_subtree(ti, ett_ipaccess); + proto_tree_add_item(ipaccess_tree, hf_ipaccess_msgtype, + tvb, 0, 1, FALSE); + switch (msg_type) { + case 4: + case 5: + dissect_ipa_attr(tvb, 1, ipaccess_tree); + break; + } + } + + return 1; +} + + +/* Code to actually dissect the packets */ +static void +dissect_abisip(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) +{ + + int offset = 0; + + if (check_col(pinfo->cinfo, COL_PROTOCOL)) + col_set_str(pinfo->cinfo, COL_PROTOCOL, "Abis/IP"); + if (check_col(pinfo->cinfo, COL_INFO)) + col_clear(pinfo->cinfo, COL_INFO); + + while (tvb_reported_length_remaining(tvb, offset) != 0) { + proto_item *ti; + proto_tree *abisip_tree; + guint8 len, msg_type; + tvbuff_t *next_tvb; + + len = tvb_get_guint8(tvb, offset+1); + msg_type = tvb_get_guint8(tvb, offset+2); + + if (check_col(pinfo->cinfo, COL_INFO)) + col_append_fstr(pinfo->cinfo, COL_INFO, "%s ", + val_to_str(msg_type, abisip_protocol_vals, + "unknown 0x%02x")); + + if (tree) { + ti = proto_tree_add_protocol_format(tree, proto_abisip, + tvb, offset, len+3, + "A-bis/IP protocol ip.access, type: %s", + val_to_str(msg_type, abisip_protocol_vals, + "unknown 0x%02x")); + abisip_tree = proto_item_add_subtree(ti, ett_abisip); + proto_tree_add_item(abisip_tree, hf_abisip_data_len, + tvb, offset+1, 1, FALSE); + proto_tree_add_item(abisip_tree, hf_abisip_protocol, + tvb, offset+2, 1, FALSE); + } + + next_tvb = tvb_new_subset(tvb, offset+3, len, len); + + switch (msg_type) { + case ABISIP_RSL: + /* hand this off to the standard A-bis RSL dissector */ + call_dissector(sub_handles[SUB_RSL], next_tvb, pinfo, tree); + break; + case ABISIP_OML: + /* hand this off to the standard A-bis OML dissector */ + if (sub_handles[SUB_OML]) + call_dissector(sub_handles[SUB_OML], next_tvb, + pinfo, tree); + break; + case ABISIP_IPACCESS: + dissect_ipaccess(next_tvb, pinfo, tree); + break; + } + offset += len + 3; + } +} + +void proto_register_abis_ip(void) +{ + static hf_register_info hf[] = { + {&hf_abisip_data_len, + {"DataLen", "abisip.data_len", + FT_UINT8, BASE_DEC, NULL, 0x0, + "The length of the data (in bytes)", HFILL} + }, + {&hf_abisip_protocol, + {"Protocol", "abisip.protocol", + FT_UINT8, BASE_HEX, VALS(abisip_protocol_vals), 0x0, + "The A-bis/IP Sub-Protocol", HFILL} + }, + }; + static hf_register_info hf_ipa[] = { + {&hf_ipaccess_msgtype, + {"MessageType", "ipaccess.msg_type", + FT_UINT8, BASE_HEX, VALS(ipaccess_msgtype_vals), 0x0, + "Type of ip.access messsage", HFILL} + }, + {&hf_ipaccess_attr_tag, + {"Tag", "ipaccess.attr_tag", + FT_UINT8, BASE_HEX, VALS(ipaccess_idtag_vals), 0x0, + "Attribute Tag", HFILL} + }, + {&hf_ipaccess_attr_string, + {"String", "ipaccess.attr_string", + FT_STRING, BASE_NONE, NULL, 0x0, + "String attribute", HFILL} + }, + }; + + static gint *ett[] = { + &ett_abisip, + &ett_ipaccess, + }; + + proto_abisip = + proto_register_protocol("GSM A-bis/IP protocol as used by ip.access", + "GSM A-bis/IP", "gsm_abis_ip"); + proto_ipaccess = + proto_register_protocol("GSM A-bis/IP ip.access CCM sub-protocol", + "IPA", "ipaccess"); + + proto_register_field_array(proto_abisip, hf, array_length(hf)); + proto_register_field_array(proto_ipaccess, hf_ipa, array_length(hf_ipa)); + proto_register_subtree_array(ett, array_length(ett)); + + register_dissector("gsm_abis_ip", dissect_abisip, proto_abisip); +} + +void proto_reg_handoff_gsm_abis_ip(void) +{ + dissector_handle_t abisip_handle; + + sub_handles[SUB_RSL] = find_dissector("gsm_abis_rsl"); + sub_handles[SUB_OML] = find_dissector("gsm_abis_oml"); + + abisip_handle = create_dissector_handle(dissect_abisip, proto_abisip); + dissector_add("tcp.port", TCP_PORT_ABISIP_PRIM, abisip_handle); + dissector_add("tcp.port", TCP_PORT_ABISIP_SEC, abisip_handle); + dissector_add("tcp.port", TCP_PORT_ABISIP_INST, abisip_handle); + dissector_add("udp.port", TCP_PORT_ABISIP_INST, abisip_handle); +} -- - Harald Welte <lafo...@gnumonks.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6) ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev@wireshark.org> Archives: http://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-requ...@wireshark.org?subject=unsubscribe