/* packet-dvb-data-mpe.c * Routines for DVB-DATA (ETSI EN 301 192) MultiProtocol Encapsulation * Copyright 2012, Guy Martin * * 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 "packet-mpeg-sect.h" void proto_register_dvb_data_mpe(void); void proto_reg_handoff_dvb_data_mpe(void); static int proto_dvb_data_mpe; static int hf_dvb_data_mpe_reserved; static int hf_dvb_data_mpe_payload_scrambling_control; static int hf_dvb_data_mpe_address_scrambling_control; static int hf_dvb_data_mpe_llc_snap_flag; static int hf_dvb_data_mpe_current_next_indicator; static int hf_dvb_data_mpe_section_number; static int hf_dvb_data_mpe_last_section_number; static int hf_dvb_data_mpe_dst_mac; static int hf_dvb_data_mpe_dst_mac_scrambled; static int ett_dvb_data_mpe; static expert_field ei_dvb_data_mpe_reserved_not_one; static expert_field ei_dvb_data_mpe_payload_scrambled; static expert_field ei_dvb_data_mpe_address_scrambled; static dissector_handle_t dvb_data_mpe_handle; static dissector_handle_t ip_handle; static dissector_handle_t llc_handle; #define DVB_DATA_MPE_RESERVED_MASK 0xC0 #define DVB_DATA_MPE_PAYLOAD_SCRAMBLING_MASK 0x30 #define DVB_DATA_MPE_ADDRESS_SCRAMBLING_MASK 0x0C #define DVB_DATA_MPE_LLC_SNAP_FLAG_MASK 0x02 #define DVB_DATA_MPE_CURRENT_NEXT_INDICATOR_MASK 0x01 /* Field positions for the MAC Address */ /* It is split into two chunks, one of two octets and a second * one of four octets. Also, the octets are in reverse order. */ #define DVB_DATA_MPE_DST_MAC_FIRST 3 #define DVB_DATA_MPE_DST_MAC_SECOND 8 static const value_string dvb_data_mpe_scrambling_vals[] = { { 0, "Unscrambled" }, { 1, "Defined by service" }, { 2, "Defined by service" }, { 3, "Defined by service" }, { 0, NULL } }; static int dissect_dvb_data_mpe(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { unsigned offset = 0, tot_len = 0; uint32_t reserved, address_scrambling, payload_scrambling, llc_snap_flag; int i; proto_item *ti; proto_tree *dvb_data_mpe_tree; unsigned char *dst = (unsigned char*)wmem_alloc(pinfo->pool, 6); address dst_addr; tvbuff_t *data_tvb; /* The TVB should start right after the section_length in the Section packet */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "DVB-DATA"); col_set_str(pinfo->cinfo, COL_INFO, "MultiProtocol Encapsulation"); ti = proto_tree_add_item(tree, proto_dvb_data_mpe, tvb, offset, -1, ENC_NA); dvb_data_mpe_tree = proto_item_add_subtree(ti, ett_dvb_data_mpe); offset += packet_mpeg_sect_header(tvb, offset, dvb_data_mpe_tree, &tot_len, NULL); /* Parse the DMC-CC private section header */ dst[5] = tvb_get_uint8(tvb, offset); offset += 1; dst[4] = tvb_get_uint8(tvb, offset); offset += 1; ti = proto_tree_add_item_ret_uint(dvb_data_mpe_tree, hf_dvb_data_mpe_reserved, tvb, offset, 1, ENC_BIG_ENDIAN, &reserved); if (reserved != 3) { expert_add_info(pinfo, ti, &ei_dvb_data_mpe_reserved_not_one); } ti = proto_tree_add_item_ret_uint(dvb_data_mpe_tree, hf_dvb_data_mpe_payload_scrambling_control, tvb, offset, 1, ENC_BIG_ENDIAN, &payload_scrambling); if (payload_scrambling) { expert_add_info(pinfo, ti, &ei_dvb_data_mpe_payload_scrambled); } proto_tree_add_item_ret_uint(dvb_data_mpe_tree, hf_dvb_data_mpe_address_scrambling_control, tvb, offset, 1, ENC_BIG_ENDIAN, &address_scrambling); proto_tree_add_item_ret_uint(dvb_data_mpe_tree, hf_dvb_data_mpe_llc_snap_flag, tvb, offset, 1, ENC_BIG_ENDIAN, &llc_snap_flag); proto_tree_add_item(dvb_data_mpe_tree, hf_dvb_data_mpe_current_next_indicator, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1; proto_tree_add_item(dvb_data_mpe_tree, hf_dvb_data_mpe_section_number, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1; proto_tree_add_item(dvb_data_mpe_tree, hf_dvb_data_mpe_last_section_number, tvb, offset, 1, ENC_BIG_ENDIAN); offset += 1; for (i = 3; i >= 0; i--) { dst[i] = tvb_get_uint8(tvb, offset); offset += 1; } if (address_scrambling) { ti = proto_tree_add_bytes_with_length(dvb_data_mpe_tree, hf_dvb_data_mpe_dst_mac_scrambled, tvb, DVB_DATA_MPE_DST_MAC_FIRST, 2, dst, 6); expert_add_info(pinfo, ti, &ei_dvb_data_mpe_address_scrambled); } else { ti = proto_tree_add_ether(dvb_data_mpe_tree, hf_dvb_data_mpe_dst_mac, tvb, DVB_DATA_MPE_DST_MAC_FIRST, 2, dst); set_address(&dst_addr, AT_ETHER, 6, dst); col_add_str(pinfo->cinfo, COL_RES_DL_DST, address_to_str(pinfo->pool, &dst_addr)); } /* Extend the highlighting for the second chunk. */ proto_tree_set_appendix(ti, tvb, DVB_DATA_MPE_DST_MAC_SECOND, 4); data_tvb = tvb_new_subset_remaining(tvb, offset); if (payload_scrambling) { call_data_dissector(data_tvb, pinfo, tree); } else if (llc_snap_flag) { call_dissector(llc_handle, data_tvb, pinfo, tree); } else { call_dissector(ip_handle, data_tvb, pinfo, tree); } packet_mpeg_sect_crc(tvb, pinfo, dvb_data_mpe_tree, 0, tot_len - 1); return tvb_captured_length(tvb); } void proto_register_dvb_data_mpe(void) { static hf_register_info hf[] = { /* DSM-CC common fields */ { &hf_dvb_data_mpe_reserved, { "Reserved", "dvb_data_mpe.reserved", FT_UINT8, BASE_HEX, NULL, DVB_DATA_MPE_RESERVED_MASK, NULL, HFILL } }, { &hf_dvb_data_mpe_payload_scrambling_control, { "Payload Scrambling Control", "dvb_data_mpe.pload_scrambling", FT_UINT8, BASE_HEX, VALS(dvb_data_mpe_scrambling_vals), DVB_DATA_MPE_PAYLOAD_SCRAMBLING_MASK, NULL, HFILL } }, { &hf_dvb_data_mpe_address_scrambling_control, { "Address Scrambling Control", "dvb_data_mpe.addr_scrambling", FT_UINT8, BASE_HEX, VALS(dvb_data_mpe_scrambling_vals), DVB_DATA_MPE_ADDRESS_SCRAMBLING_MASK, NULL, HFILL } }, { &hf_dvb_data_mpe_llc_snap_flag, { "LLC SNAP Flag", "dvb_data_mpe.llc_snap_flag", FT_UINT8, BASE_HEX, NULL, DVB_DATA_MPE_LLC_SNAP_FLAG_MASK, NULL, HFILL } }, { &hf_dvb_data_mpe_current_next_indicator, { "Current/Next Indicator", "mpeg_sect.cur_next_ind", FT_BOOLEAN, 8, TFS(&tfs_current_not_yet), DVB_DATA_MPE_CURRENT_NEXT_INDICATOR_MASK, NULL, HFILL } }, { &hf_dvb_data_mpe_section_number, { "Section Number", "dvb_data_mpe.sect_num", FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL } }, { &hf_dvb_data_mpe_last_section_number, { "Last Section Number", "dvb_data_mpe.last_sect_num", FT_UINT8, BASE_DEC, NULL, 0, NULL, HFILL } }, { &hf_dvb_data_mpe_dst_mac, { "Destination MAC address", "dvb_data_mpe.dst_mac", FT_ETHER, BASE_NONE, NULL, 0, NULL, HFILL } }, { &hf_dvb_data_mpe_dst_mac_scrambled, { "Destination MAC address (scrambled)", "dvb_data_mpe.dst_mac.scrambled", FT_BYTES, SEP_COLON, NULL, 0, NULL, HFILL } }, }; static int *ett[] = { &ett_dvb_data_mpe, }; expert_module_t *expert_dvb_data_mpe; static ei_register_info ei[] = { { &ei_dvb_data_mpe_reserved_not_one, { "dvb_data_mpe.reserved.not_one", PI_PROTOCOL, PI_WARN, "Reserved bits not all ones", EXPFILL }}, { &ei_dvb_data_mpe_address_scrambled, { "dvb_data_mpe.address_scrambled", PI_UNDECODED, PI_WARN, "Cannot descramble destination MAC address (user private scrambling)", EXPFILL }}, { &ei_dvb_data_mpe_payload_scrambled, { "dvb_data_mpe.payload.scrambled", PI_UNDECODED, PI_WARN, "Cannot descramble payload (user private scrambling)", EXPFILL }}, }; proto_dvb_data_mpe = proto_register_protocol("DVB-DATA MultiProtocol Encapsulation", "DVB-DATA MPE", "dvb_data_mpe"); proto_register_field_array(proto_dvb_data_mpe, hf, array_length(hf)); expert_dvb_data_mpe = expert_register_protocol(proto_dvb_data_mpe); expert_register_field_array(expert_dvb_data_mpe, ei, array_length(ei)); proto_register_subtree_array(ett, array_length(ett)); dvb_data_mpe_handle = register_dissector("dvb_data_mpe", dissect_dvb_data_mpe, proto_dvb_data_mpe); } void proto_reg_handoff_dvb_data_mpe(void) { dissector_add_uint("mpeg_sect.tid", DVB_DATA_MPE_TID, dvb_data_mpe_handle); ip_handle = find_dissector_add_dependency("ip", proto_dvb_data_mpe); llc_handle = find_dissector_add_dependency("llc", proto_dvb_data_mpe); } /* * 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: */