/* packet-tali.c * * Routines for Transport Adapter Layer Interface (TALI) version 1.0 dissection (RFC 3094) * * Copyright : 2004 Viorel Suman, * In association with Avalanche Mobile BV, http://www.avmob.com * * Dissector of a TALI (Transport Adapter Layer Interface) version 1.0, as defined by the * Tekelec (www.tekelec.com) in RFC 3094, https://www.ietf.org/rfc/rfc3094 * * Refer to the AUTHORS file or the AUTHORS section in the man page * for contacting the author(s) of this file. * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include "packet-tcp.h" #define TALI_SYNC_LENGTH 4 #define TALI_OPCODE_LENGTH 4 #define TALI_MSU_LENGTH 2 #define TALI_HEADER_LENGTH TALI_SYNC_LENGTH + TALI_OPCODE_LENGTH + TALI_MSU_LENGTH #define TALI_SYNC "TALI" #define TALI_TEST "test" #define TALI_ALLO "allo" #define TALI_PROH "proh" #define TALI_PROA "proa" #define TALI_MONI "moni" #define TALI_MONA "mona" #define TALI_SCCP "sccp" #define TALI_ISOT "isot" #define TALI_MTP3 "mtp3" #define TALI_SAAL "saal" void proto_reg_handoff_tali(void); void proto_register_tali(void); static int proto_tali; static int hf_tali_length_indicator; static int hf_tali_opcode_indicator; static int hf_tali_sync_indicator; /* Initialize the subtree pointers */ static gint ett_tali; static gint ett_tali_sync; static gint ett_tali_opcode; static gint ett_tali_msu_length; static dissector_table_t tali_dissector_table; /* Desegment TALI messages */ static gboolean tali_desegment = TRUE; /* Code to actually dissect the packets */ static guint get_tali_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset, void *data _U_) { guint16 length; length = tvb_get_letohs(tvb, offset + TALI_SYNC_LENGTH + TALI_OPCODE_LENGTH); return length+TALI_HEADER_LENGTH; } static int dissect_tali_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { char *opcode; /* TALI opcode */ guint16 length; /* TALI length */ tvbuff_t *payload_tvb = NULL; /* Set up structures needed to add the protocol subtree and manage it */ proto_item *tali_item = NULL; proto_tree *tali_tree = NULL; opcode = (char *) tvb_get_string_enc(pinfo->pool, tvb, TALI_SYNC_LENGTH, TALI_OPCODE_LENGTH, ENC_ASCII|ENC_NA); length = tvb_get_letohs(tvb, TALI_SYNC_LENGTH + TALI_OPCODE_LENGTH); /* Make entries in Protocol column on summary display */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "TALI"); col_clear(pinfo->cinfo, COL_INFO); col_append_fstr(pinfo->cinfo, COL_INFO, "[%s] packet, [%u] bytes in payload", opcode, length); if (tree) { /* create display subtree for the protocol */ tali_item = proto_tree_add_item(tree, proto_tali, tvb, 0, TALI_HEADER_LENGTH, ENC_NA); tali_tree = proto_item_add_subtree(tali_item, ett_tali); proto_tree_add_string(tali_tree, hf_tali_sync_indicator, tvb, 0, TALI_SYNC_LENGTH, TALI_SYNC); proto_tree_add_string(tali_tree, hf_tali_opcode_indicator, tvb, TALI_SYNC_LENGTH, TALI_OPCODE_LENGTH, opcode); proto_tree_add_uint(tali_tree, hf_tali_length_indicator, tvb, TALI_SYNC_LENGTH + TALI_OPCODE_LENGTH, TALI_MSU_LENGTH, length); } if (length > 0) { payload_tvb = tvb_new_subset_remaining(tvb, TALI_HEADER_LENGTH); if (payload_tvb != NULL && !dissector_try_string(tali_dissector_table, opcode, payload_tvb, pinfo, tree, NULL)) { call_data_dissector(payload_tvb, pinfo, tree); } } return tvb_captured_length(tvb); } static int dissect_tali(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data) { tcp_dissect_pdus(tvb, pinfo, tree, tali_desegment, TALI_HEADER_LENGTH, get_tali_pdu_len, dissect_tali_pdu, data); return tvb_captured_length(tvb); } /* * A 'heuristic dissector' that attemtps to establish whether we have * a TALI MSU here. * Only works when: * the fixed header is there * it is a 'well-known' operation */ static gboolean dissect_tali_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) { char opcode[TALI_OPCODE_LENGTH]; /* TALI opcode */ /* * If we don't have at least TALI_HEADER_LENGTH bytes worth of captured * data (i.e., available to look at), we can't determine whether this * looks like a TALI packet or not. We must use tvb_captured_length() * because the data must be present in the capture, not sliced off due * to the snapshot length specified for the capture. */ if (tvb_captured_length(tvb) < TALI_HEADER_LENGTH) /* Mandatory header */ return FALSE; if (tvb_strneql(tvb, 0, TALI_SYNC, TALI_SYNC_LENGTH) != 0) return FALSE; tvb_memcpy(tvb, (guint8*)opcode, TALI_SYNC_LENGTH, TALI_OPCODE_LENGTH); if (strncmp(opcode, TALI_TEST, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_ALLO, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_PROH, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_PROA, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_MONI, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_MONA, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_SCCP, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_ISOT, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_MTP3, TALI_OPCODE_LENGTH) != 0 && strncmp(opcode, TALI_SAAL, TALI_OPCODE_LENGTH) != 0) return FALSE; dissect_tali(tvb, pinfo, tree, data); return TRUE; } void proto_register_tali(void) { static hf_register_info hf[] = { { &hf_tali_sync_indicator, { "Sync", "tali.sync", FT_STRING, BASE_NONE, NULL, 0x00, "TALI SYNC", HFILL } }, { &hf_tali_opcode_indicator, { "Opcode", "tali.opcode", FT_STRING, BASE_NONE, NULL, 0x00, "TALI Operation Code", HFILL } }, { &hf_tali_length_indicator, { "Length", "tali.msu_length", FT_UINT16, BASE_DEC, NULL, 0x00, "TALI MSU Length", HFILL } }, }; /* Setup protocol subtree array */ static gint *ett[] = { &ett_tali, &ett_tali_sync, &ett_tali_opcode, &ett_tali_msu_length }; module_t *tali_module; /* Register the protocol name and description */ proto_tali = proto_register_protocol("Transport Adapter Layer Interface v1.0, RFC 3094", "TALI", "tali"); proto_register_field_array(proto_tali, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("tali", dissect_tali, proto_tali); tali_dissector_table = register_dissector_table("tali.opcode", "Tali OPCODE", proto_tali, FT_STRING, STRING_CASE_SENSITIVE); tali_module = prefs_register_protocol(proto_tali, NULL); prefs_register_bool_preference(tali_module, "reassemble", "Reassemble TALI messages spanning multiple TCP segments", "Whether the TALI dissector should reassemble messages spanning multiple TCP segments." " To use this option, you must also enable \"Allow subdissectors to reassemble TCP streams\" in the TCP protocol settings.", &tali_desegment); } void proto_reg_handoff_tali(void) { heur_dissector_add("tcp", dissect_tali_heur, "Tali over TCP", "tali_tcp", proto_tali, HEURISTIC_ENABLE); } /* * Editor modelines - https://www.wireshark.org/tools/modelines.html * * Local Variables: * c-basic-offset: 2 * tab-width: 8 * indent-tabs-mode: nil * End: * * ex: set shiftwidth=2 tabstop=8 expandtab: * :indentSize=2:tabSize=8:noTabs=true: */