/* packet-lmi.c * Routines for Frame Relay Local Management Interface (LMI) disassembly * Copyright 2001, Jeffrey C. Foster * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 * * SPDX-License-Identifier: GPL-2.0-or-later * * ToDo: * * References: * * http://www.techfest.com/networking/wan/frrel.htm * https://www.broadband-forum.org/technical/download/FRF.1.2/frf1_2.pdf * http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/frame.htm#xtocid18 * http://www.net.aapt.com.au/techref/lmimess.htm * http://www.raleigh.ibm.com:80/cgi-bin/bookmgr/BOOKS/EZ305800/1.2.4.4 */ #include "config.h" #include #include void proto_register_lmi(void); void proto_reg_handoff_lmi(void); static dissector_handle_t lmi_handle; static int proto_lmi = -1; static int hf_lmi_call_ref = -1; static int hf_lmi_msg_type = -1; static int hf_lmi_inf_ele = -1; static int hf_lmi_inf_len = -1; static int hf_lmi_rcd_type = -1; static int hf_lmi_send_seq = -1; static int hf_lmi_recv_seq = -1; static int hf_lmi_dlci_high = -1; static int hf_lmi_dlci_low = -1; static int hf_lmi_new = -1; static int hf_lmi_act = -1; static gint ett_lmi = -1; static gint ett_lmi_ele = -1; #ifdef _OLD_ /* * Bits in the address field. */ #define LMI_CMD 0xf000 /* LMI Command */ #define LMI_SEQ 0x0fff /* LMI Sequence number */ #endif static const value_string msg_type_str[] = { {0x75, "Status Enquiry"}, {0x7D, "Status"}, { 0, NULL } }; static const value_string element_type_str[] = { /*** These are the ANSI values ***/ {0x01, "Report"}, {0x03, "Keep Alive"}, {0x07, "PVC Status"}, /*** These are the ITU values ***/ {0x51, "Report"}, {0x53, "Keep Alive"}, {0x07, "PVC Status"}, {0, NULL } }; static const value_string record_type_str[] = { {0x00, "Full Status"}, {0x01, "Link Integrity Verification Only"}, {0x02, "Single PVC"}, {0, NULL } }; static const value_string pvc_status_new_str[] = { {0x00, "PVC already present"}, {0x01, "PVC is new"}, {0, NULL } }; static const value_string pvc_status_act_str[] = { {0x00, "PVC is Inactive"}, {0x01, "PVC is Active"}, {0, NULL } }; static void dissect_lmi_report_type(tvbuff_t *tvb, int offset, proto_tree *tree) { proto_tree_add_item(tree, hf_lmi_rcd_type, tvb, offset, 1, ENC_NA); } static void dissect_lmi_link_int(tvbuff_t *tvb, int offset, proto_tree *tree) { proto_tree_add_item(tree, hf_lmi_send_seq, tvb, offset, 1, ENC_NA); ++offset; proto_tree_add_item(tree, hf_lmi_recv_seq, tvb, offset, 1, ENC_NA); } static void dissect_lmi_pvc_status(tvbuff_t *tvb, int offset, proto_tree *tree) { proto_tree_add_item(tree, hf_lmi_dlci_high, tvb, offset, 1, ENC_NA); ++offset; proto_tree_add_item(tree, hf_lmi_dlci_low, tvb, offset, 1, ENC_NA); ++offset; proto_tree_add_item(tree, hf_lmi_new, tvb, offset, 1, ENC_NA); proto_tree_add_item(tree, hf_lmi_act, tvb, offset, 1, ENC_NA); } static int dissect_lmi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { proto_tree *lmi_tree, *lmi_subtree; proto_item *ti; int offset = 2, len; guint8 msg_type; guint8 ele_id; col_set_str(pinfo->cinfo, COL_PROTOCOL, "LMI"); col_clear(pinfo->cinfo, COL_INFO); ti = proto_tree_add_item(tree, proto_lmi, tvb, 0, 3, ENC_NA); lmi_tree = proto_item_add_subtree(ti, ett_lmi_ele); proto_tree_add_item(lmi_tree, hf_lmi_call_ref, tvb, 0, 1, ENC_BIG_ENDIAN); msg_type = tvb_get_guint8( tvb, 1); col_add_str(pinfo->cinfo, COL_INFO, val_to_str(msg_type, msg_type_str, "Unknown message type (0x%02x)")); proto_tree_add_uint(lmi_tree, hf_lmi_msg_type, tvb, 1, 1, msg_type); /* Display the LMI elements */ while (tvb_reported_length_remaining(tvb, offset) > 0) { ele_id = tvb_get_guint8( tvb, offset); len = tvb_get_guint8( tvb, offset + 1); lmi_subtree = proto_tree_add_subtree_format(lmi_tree, tvb, offset, len + 2, ett_lmi_ele, NULL, "Information Element: %s", val_to_str(ele_id, element_type_str, "Unknown (%u)")); proto_tree_add_uint(lmi_subtree, hf_lmi_inf_ele, tvb, offset, 1, ele_id); ++offset; proto_tree_add_uint(lmi_subtree, hf_lmi_inf_len, tvb, offset, 1, len); ++offset; if (( ele_id == 1) || (ele_id == 51)) dissect_lmi_report_type( tvb, offset, lmi_subtree); else if (( ele_id == 3) || (ele_id == 53)) dissect_lmi_link_int( tvb, offset, lmi_subtree); else if (( ele_id == 7) || (ele_id == 57)) dissect_lmi_pvc_status( tvb, offset, lmi_subtree); offset += len; } return tvb_captured_length(tvb); } void proto_register_lmi(void) { static hf_register_info hf[] = { { &hf_lmi_call_ref, { "Call reference", "lmi.cmd", FT_UINT8, BASE_HEX, NULL, 0, NULL, HFILL }}, { &hf_lmi_msg_type, { "Message Type", "lmi.msg_type", FT_UINT8, BASE_HEX, VALS(msg_type_str), 0, NULL, HFILL }}, { &hf_lmi_inf_ele, { "Type", "lmi.inf_ele_type", FT_UINT8, BASE_DEC, VALS(element_type_str), 0, "Information Element Type", HFILL }}, { &hf_lmi_inf_len, { "Length", "lmi.inf_ele_len", FT_UINT8, BASE_DEC, NULL, 0, "Information Element Length", HFILL }}, { &hf_lmi_rcd_type, { "Record Type", "lmi.ele_rcd_type", FT_UINT8, BASE_DEC, VALS(record_type_str), 0, NULL, HFILL }}, { &hf_lmi_send_seq, { "Send Seq", "lmi.send_seq", FT_UINT8, BASE_DEC, NULL, 0, "Send Sequence", HFILL }}, { &hf_lmi_recv_seq, { "Recv Seq", "lmi.recv_seq", FT_UINT8, BASE_DEC, NULL, 0, "Receive Sequence", HFILL }}, { &hf_lmi_dlci_high, { "DLCI High", "lmi.dlci_hi", FT_UINT8, BASE_DEC, NULL, 0x3f, "DLCI High bits", HFILL }}, { &hf_lmi_dlci_low, { "DLCI Low", "lmi.dlci_low", FT_UINT8, BASE_DEC, NULL, 0x78, "DLCI Low bits", HFILL }}, { &hf_lmi_new, { "DLCI New", "lmi.dlci_new", FT_UINT8, BASE_DEC, VALS(pvc_status_new_str), 0x08, "DLCI New Flag", HFILL }}, { &hf_lmi_act, { "DLCI Active","lmi.dlci_act", FT_UINT8, BASE_DEC, VALS(pvc_status_act_str), 0x02, "DLCI Active Flag", HFILL }}, }; static gint *ett[] = { &ett_lmi, &ett_lmi_ele, }; proto_lmi = proto_register_protocol ("Local Management Interface", "LMI", "lmi"); proto_register_field_array (proto_lmi, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); lmi_handle = register_dissector("lmi", dissect_lmi, proto_lmi); } void proto_reg_handoff_lmi(void) { dissector_add_uint("fr.nlpid", NLPID_LMI, lmi_handle); } /* * Editor modelines - https://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 4 * tab-width: 8 * indent-tabs-mode: nil * End: * * vi: set shiftwidth=4 tabstop=8 expandtab: * :indentSize=4:tabSize=8:noTabs=true: */