/* packet-rtse-template.c * Routines for RTSE packet dissection * Graeme Lunt 2005 * * 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 #include #include #include #include #include "packet-ber.h" #include "packet-pres.h" #include "packet-acse.h" #include "packet-ros.h" #include "packet-rtse.h" #define PNAME "X.228 OSI Reliable Transfer Service" #define PSNAME "RTSE" #define PFNAME "rtse" void proto_register_rtse(void); void proto_reg_handoff_rtse(void); /* Initialize the protocol and registered fields */ static int proto_rtse = -1; static gboolean open_request=FALSE; static guint32 app_proto=0; static proto_tree *top_tree=NULL; /* Preferences */ static gboolean rtse_reassemble = TRUE; #include "packet-rtse-hf.c" /* Initialize the subtree pointers */ static gint ett_rtse = -1; #include "packet-rtse-ett.c" static expert_field ei_rtse_dissector_oid_not_implemented = EI_INIT; static expert_field ei_rtse_unknown_rtse_pdu = EI_INIT; static expert_field ei_rtse_abstract_syntax = EI_INIT; static dissector_table_t rtse_oid_dissector_table=NULL; static dissector_handle_t rtse_handle = NULL; static gint ett_rtse_unknown = -1; static reassembly_table rtse_reassembly_table; static int hf_rtse_segment_data = -1; static int hf_rtse_fragments = -1; static int hf_rtse_fragment = -1; static int hf_rtse_fragment_overlap = -1; static int hf_rtse_fragment_overlap_conflicts = -1; static int hf_rtse_fragment_multiple_tails = -1; static int hf_rtse_fragment_too_long_fragment = -1; static int hf_rtse_fragment_error = -1; static int hf_rtse_fragment_count = -1; static int hf_rtse_reassembled_in = -1; static int hf_rtse_reassembled_length = -1; static gint ett_rtse_fragment = -1; static gint ett_rtse_fragments = -1; static const fragment_items rtse_frag_items = { /* Fragment subtrees */ &ett_rtse_fragment, &ett_rtse_fragments, /* Fragment fields */ &hf_rtse_fragments, &hf_rtse_fragment, &hf_rtse_fragment_overlap, &hf_rtse_fragment_overlap_conflicts, &hf_rtse_fragment_multiple_tails, &hf_rtse_fragment_too_long_fragment, &hf_rtse_fragment_error, &hf_rtse_fragment_count, /* Reassembled in field */ &hf_rtse_reassembled_in, /* Reassembled length field */ &hf_rtse_reassembled_length, /* Reassembled data field */ NULL, /* Tag */ "RTSE fragments" }; void register_rtse_oid_dissector_handle(const char *oid, dissector_handle_t dissector, int proto, const char *name, gboolean uses_ros) { /* XXX: Note that this fcn is called from proto_reg_handoff in *other* dissectors ... */ static dissector_handle_t ros_handle = NULL; if (ros_handle == NULL) ros_handle = find_dissector("ros"); /* register RTSE with the BER (ACSE) */ register_ber_oid_dissector_handle(oid, rtse_handle, proto, name); if (uses_ros) { /* make sure we call ROS ... */ dissector_add_string("rtse.oid", oid, ros_handle); /* and then tell ROS how to dissect the AS*/ if (dissector != NULL) register_ros_oid_dissector_handle(oid, dissector, proto, name, TRUE); } else { /* otherwise we just remember how to dissect the AS */ dissector_add_string("rtse.oid", oid, dissector); } } static int call_rtse_oid_callback(const char *oid, tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tree, void* data) { tvbuff_t *next_tvb; int len; next_tvb = tvb_new_subset_remaining(tvb, offset); if ((len = dissector_try_string(rtse_oid_dissector_table, oid, next_tvb, pinfo, tree, data)) == 0) { proto_item *item; proto_tree *next_tree; next_tree = proto_tree_add_subtree_format(tree, next_tvb, 0, -1, ett_rtse_unknown, &item, "RTSE: Dissector for OID:%s not implemented. Contact Wireshark developers if you want this supported", oid); expert_add_info_format(pinfo, item, &ei_rtse_dissector_oid_not_implemented, "RTSE: Dissector for OID %s not implemented", oid); len = dissect_unknown_ber(pinfo, next_tvb, offset, next_tree); } offset += len; return offset; } static int call_rtse_external_type_callback(bool implicit_tag _U_, tvbuff_t *tvb, int offset, asn1_ctx_t *actx, proto_tree *tree, int hf_index _U_) { const char *oid = NULL; if (actx->external.indirect_ref_present) { oid = (const char *)find_oid_by_pres_ctx_id(actx->pinfo, actx->external.indirect_reference); if (!oid) proto_tree_add_expert_format(tree, actx->pinfo, &ei_rtse_abstract_syntax, tvb, offset, tvb_captured_length_remaining(tvb, offset), "Unable to determine abstract syntax for indirect reference: %d.", actx->external.indirect_reference); } else if (actx->external.direct_ref_present) { oid = actx->external.direct_reference; } if (oid) offset = call_rtse_oid_callback(oid, tvb, offset, actx->pinfo, top_tree ? top_tree : tree, actx->private_data); return offset; } #include "packet-rtse-fn.c" /* * Dissect RTSE PDUs inside a PPDU. */ static int dissect_rtse(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void* data) { int offset = 0; int old_offset; proto_item *item; proto_tree *tree; proto_tree *next_tree=NULL; tvbuff_t *next_tvb = NULL; tvbuff_t *data_tvb = NULL; fragment_head *frag_msg = NULL; guint32 fragment_length; guint32 rtse_id = 0; gboolean data_handled = FALSE; struct SESSION_DATA_STRUCTURE* session; conversation_t *conversation = NULL; asn1_ctx_t asn1_ctx; asn1_ctx_init(&asn1_ctx, ASN1_ENC_BER, TRUE, pinfo); /* do we have application context from the acse dissector? */ if (data == NULL) return 0; session = (struct SESSION_DATA_STRUCTURE*)data; /* save parent_tree so subdissectors can create new top nodes */ top_tree=parent_tree; asn1_ctx.private_data = session; col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTSE"); col_clear(pinfo->cinfo, COL_INFO); if (rtse_reassemble && ((session->spdu_type == SES_DATA_TRANSFER) || (session->spdu_type == SES_MAJOR_SYNC_POINT))) { /* Use conversation index as fragment id */ conversation = find_conversation_pinfo(pinfo, 0); if (conversation != NULL) { rtse_id = conversation->conv_index; } session->rtse_reassemble = TRUE; } if (rtse_reassemble && session->spdu_type == SES_MAJOR_SYNC_POINT) { frag_msg = fragment_end_seq_next (&rtse_reassembly_table, pinfo, rtse_id, NULL); next_tvb = process_reassembled_data (tvb, offset, pinfo, "Reassembled RTSE", frag_msg, &rtse_frag_items, NULL, parent_tree); } item = proto_tree_add_item(parent_tree, proto_rtse, next_tvb ? next_tvb : tvb, 0, -1, ENC_NA); tree = proto_item_add_subtree(item, ett_rtse); if (rtse_reassemble && session->spdu_type == SES_DATA_TRANSFER) { /* strip off the OCTET STRING encoding - including any CONSTRUCTED OCTET STRING */ dissect_ber_octet_string(FALSE, &asn1_ctx, tree, tvb, offset, hf_rtse_segment_data, &data_tvb); if (data_tvb) { fragment_length = tvb_captured_length_remaining (data_tvb, 0); proto_item_append_text(asn1_ctx.created_item, " (%u byte%s)", fragment_length, plurality(fragment_length, "", "s")); frag_msg = fragment_add_seq_next (&rtse_reassembly_table, data_tvb, 0, pinfo, rtse_id, NULL, fragment_length, TRUE); if (frag_msg && pinfo->num != frag_msg->reassembled_in) { /* Add a "Reassembled in" link if not reassembled in this frame */ proto_tree_add_uint (tree, *(rtse_frag_items.hf_reassembled_in), data_tvb, 0, 0, frag_msg->reassembled_in); } pinfo->fragmented = TRUE; data_handled = TRUE; } else { fragment_length = tvb_captured_length_remaining (tvb, offset); } col_append_fstr(pinfo->cinfo, COL_INFO, "[RTSE fragment, %u byte%s]", fragment_length, plurality(fragment_length, "", "s")); } else if (rtse_reassemble && session->spdu_type == SES_MAJOR_SYNC_POINT) { if (next_tvb) { /* ROS won't do this for us */ session->ros_op = (ROS_OP_INVOKE | ROS_OP_ARGUMENT); /*offset=*/dissect_ber_external_type(FALSE, tree, next_tvb, 0, &asn1_ctx, -1, call_rtse_external_type_callback); top_tree = NULL; /* Return other than 0 to indicate that we handled this packet */ return 1; } else { offset = tvb_captured_length (tvb); } pinfo->fragmented = FALSE; data_handled = TRUE; } if (!data_handled) { while (tvb_reported_length_remaining(tvb, offset) > 0) { old_offset=offset; offset=dissect_rtse_RTSE_apdus(TRUE, tvb, offset, &asn1_ctx, tree, -1); if (offset == old_offset) { next_tree = proto_tree_add_subtree(tree, tvb, offset, -1, ett_rtse_unknown, &item, "Unknown RTSE PDU"); expert_add_info (pinfo, item, &ei_rtse_unknown_rtse_pdu); dissect_unknown_ber(pinfo, tvb, offset, next_tree); break; } } } top_tree = NULL; return tvb_captured_length(tvb); } /*--- proto_register_rtse -------------------------------------------*/ void proto_register_rtse(void) { /* List of fields */ static hf_register_info hf[] = { /* Fragment entries */ { &hf_rtse_segment_data, { "RTSE segment data", "rtse.segment", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_rtse_fragments, { "RTSE fragments", "rtse.fragments", FT_NONE, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_rtse_fragment, { "RTSE fragment", "rtse.fragment", FT_FRAMENUM, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_rtse_fragment_overlap, { "RTSE fragment overlap", "rtse.fragment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_rtse_fragment_overlap_conflicts, { "RTSE fragment overlapping with conflicting data", "rtse.fragment.overlap.conflicts", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_rtse_fragment_multiple_tails, { "RTSE has multiple tail fragments", "rtse.fragment.multiple_tails", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_rtse_fragment_too_long_fragment, { "RTSE fragment too long", "rtse.fragment.too_long_fragment", FT_BOOLEAN, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_rtse_fragment_error, { "RTSE defragmentation error", "rtse.fragment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x00, NULL, HFILL } }, { &hf_rtse_fragment_count, { "RTSE fragment count", "rtse.fragment.count", FT_UINT32, BASE_DEC, NULL, 0x00, NULL, HFILL } }, { &hf_rtse_reassembled_in, { "Reassembled RTSE in frame", "rtse.reassembled.in", FT_FRAMENUM, BASE_NONE, NULL, 0x00, "This RTSE packet is reassembled in this frame", HFILL } }, { &hf_rtse_reassembled_length, { "Reassembled RTSE length", "rtse.reassembled.length", FT_UINT32, BASE_DEC, NULL, 0x00, "The total length of the reassembled payload", HFILL } }, #include "packet-rtse-hfarr.c" }; /* List of subtrees */ static gint *ett[] = { &ett_rtse, &ett_rtse_unknown, &ett_rtse_fragment, &ett_rtse_fragments, #include "packet-rtse-ettarr.c" }; static ei_register_info ei[] = { { &ei_rtse_dissector_oid_not_implemented, { "rtse.dissector_oid_not_implemented", PI_UNDECODED, PI_WARN, "RTSE: Dissector for OID not implemented", EXPFILL }}, { &ei_rtse_unknown_rtse_pdu, { "rtse.unknown_rtse_pdu", PI_UNDECODED, PI_WARN, "Unknown RTSE PDU", EXPFILL }}, { &ei_rtse_abstract_syntax, { "rtse.bad_abstract_syntax", PI_PROTOCOL, PI_WARN, "Unable to determine abstract syntax for indirect reference", EXPFILL }}, }; expert_module_t* expert_rtse; module_t *rtse_module; /* Register protocol */ proto_rtse = proto_register_protocol(PNAME, PSNAME, PFNAME); rtse_handle = register_dissector("rtse", dissect_rtse, proto_rtse); /* Register fields and subtrees */ proto_register_field_array(proto_rtse, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); expert_rtse = expert_register_protocol(proto_rtse); expert_register_field_array(expert_rtse, ei, array_length(ei)); reassembly_table_register (&rtse_reassembly_table, &addresses_reassembly_table_functions); rtse_module = prefs_register_protocol_subtree("OSI", proto_rtse, NULL); prefs_register_bool_preference(rtse_module, "reassemble", "Reassemble segmented RTSE datagrams", "Whether segmented RTSE datagrams should be reassembled." " To use this option, you must also enable" " \"Allow subdissectors to reassemble TCP streams\"" " in the TCP protocol settings.", &rtse_reassemble); rtse_oid_dissector_table = register_dissector_table("rtse.oid", "RTSE OID Dissectors", proto_rtse, FT_STRING, STRING_CASE_SENSITIVE); } /*--- proto_reg_handoff_rtse --- */ void proto_reg_handoff_rtse(void) { } /* * 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: */