/* packet-gfp.c * Routines for Generic Framing Procedure dissection * Copyright 2015, John Thacker * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ /* * Generic Framing Procedure (GFP) is used to map octet-aligned variable * length payloads (e.g. Ethernet, MPLS, octet-aligned PPP, IP) into * octet-synchronous signals such as SONET/SDH (ITU-T G.707) and OTN * (ITU-T G.709). GFP is a telecommunications industry standard defined in * ITU-T G.7041/Y.1303. * * Reference: * https://www.itu.int/rec/T-REC-G.7041/ */ #include #include /* Should be first Wireshark include (other than config.h) */ #include #include #include #include #include #include #include /* Prototypes */ /* (Required to prevent [-Wmissing-prototypes] warnings */ void proto_reg_handoff_gfp(void); void proto_register_gfp(void); /* Dissector handle */ static dissector_handle_t gfp_handle; /* Initialize the protocol and registered fields */ static int proto_gfp = -1; static int hf_gfp_pli = -1; static int hf_gfp_chec = -1; static int hf_gfp_chec_status = -1; static int hf_gfp_type = -1; static int hf_gfp_pti = -1; static int hf_gfp_pfi = -1; static int hf_gfp_exi = -1; static int hf_gfp_upi_data = -1; static int hf_gfp_upi_management = -1; static int hf_gfp_thec = -1; static int hf_gfp_thec_status = -1; static int hf_gfp_cid = -1; static int hf_gfp_ehec = -1; static int hf_gfp_ehec_status = -1; static int hf_gfp_fcs = -1; static int hf_gfp_fcs_good = -1; static int hf_gfp_fcs_bad = -1; static expert_field ei_gfp_pli_idle_nonempty = EI_INIT; static expert_field ei_gfp_pli_unknown = EI_INIT; static expert_field ei_gfp_pli_invalid = EI_INIT; static expert_field ei_gfp_chec_bad = EI_INIT; static expert_field ei_gfp_thec_bad = EI_INIT; static expert_field ei_gfp_ehec_bad = EI_INIT; static expert_field ei_gfp_exi_short = EI_INIT; static expert_field ei_gfp_pfi_short = EI_INIT; static expert_field ei_gfp_payload_undecoded = EI_INIT; static expert_field ei_gfp_fcs_bad = EI_INIT; #define GFP_USER_DATA 0 #define GFP_CLIENT_MANAGEMENT 4 #define GFP_MANAGEMENT_COMMUNICATIONS 5 #define GFP_EXT_NULL 0 #define GFP_EXT_LINEAR 1 #define GFP_EXT_RING 2 /* Initialize the subtree pointers */ static gint ett_gfp = -1; static gint ett_gfp_type = -1; static gint ett_gfp_fcs = -1; static dissector_table_t gfp_dissector_table; /* ITU-T G.7041 6.1.1, 6.2 */ static const range_string gfp_pli_rvals[] = { {0, 0, "Idle Frame"}, {1, 3, "Control Frame (Reserved)"}, {4, G_MAXUINT16, "Client Frame"}, {0, 0, NULL} }; static int * const gfp_type_data_fields[] = { &hf_gfp_pti, &hf_gfp_pfi, &hf_gfp_exi, &hf_gfp_upi_data, NULL }; static int * const gfp_type_management_fields[] = { &hf_gfp_pti, &hf_gfp_pfi, &hf_gfp_exi, &hf_gfp_upi_management, NULL }; static const value_string gfp_pti_vals[] = { {GFP_USER_DATA, "User Data"}, {GFP_CLIENT_MANAGEMENT, "Client Management"}, {GFP_MANAGEMENT_COMMUNICATIONS, "Management Communications"}, {0, NULL} }; static const value_string gfp_exi_vals[] = { {GFP_EXT_NULL, "Null Extension Header"}, {GFP_EXT_LINEAR, "Linear Frame"}, {GFP_EXT_RING, "Ring Frame"}, {0, NULL} }; static const range_string gfp_upi_data_rvals[] = { {0, 0, "Reserved and not available"}, {1, 1, "Frame-Mapped Ethernet"}, {2, 2, "Frame-Mapped PPP"}, {3, 3, "Transparent Fibre Channel"}, {4, 4, "Transparent FICON"}, {5, 5, "Transparent ESCON"}, {6, 6, "Transparent Gbit Ethernet"}, {7, 7, "Reserved"}, {8, 8, "Frame-Mapped Multiple Access Protocol over SDH (MAPOS)"}, {9, 9, "Transparent DVB ASI"}, {10, 10, "Frame-Mapped IEEE 802.17 Resilient Packet Ring"}, {11, 11, "Frame-Mapped Fibre Channel FC-BBW"}, {12, 12, "Asynchronous Transparent Fibre Channel"}, {13, 13, "Frame-Mapped MPLS"}, {14, 14, "Frame-Mapped MPLS (Multicast) [Deprecated]"}, {15, 15, "Frame-Mapped OSI network layer protocols (IS-IS, ES-IS, CLNP)"}, {16, 16, "Frame-Mapped IPv4"}, {17, 17, "Frame-Mapped IPv6"}, {18, 18, "Frame-Mapped DVB-ASI"}, {19, 19, "Frame-Mapped 64B/66B encoded Ethernet, including frame preamble"}, {20, 20, "Frame-Mapped 64B/66B encoded Ethernet ordered set information"}, {21, 21, "Transparent transcoded FC-1200"}, /*UPI value 22 & 23 from Amendment 3 (01/2015)*/ {22, 22, "Precision Time Protocol message"}, {23, 23, "Synchronization status message"}, {24, 239, "Reserved for future standardization"}, {240, 252, "Reserved for proprietary use"}, {253, 253, "Reserved for proprietary use, formerly Frame-Mapped 64B/66B encoded Ethernet, including frame preamble"}, {254, 254, "Reserved for proprietary use, formerly Frame-Mapped 64B/66B encoded Ethernet ordered set information"}, {255, 255, "Reserved and not available"}, {0, 0, NULL } }; static const range_string gfp_upi_management_rvals[] = { {0, 0, "Reserved and not available"}, {1, 1, "Client Signal Fail (Loss of Client Signal)"}, {2, 2, "Client Signal Fail (Loss of Character Synchronisation)"}, {3, 3, "Defect Clear Indication (DCI)"}, {4, 4, "Forward Defect Indication (FDI)"}, {5, 5, "Reverse Defect Indication (RDI)"}, {6, 223, "Reserved for future use"}, {224, 254, "Reserved for proprietary use"}, {255, 255, "Reserved and not available"}, {0, 0, NULL} }; /* Even GFP idle frames must have 4 bytes for the core header. * If data is received with fewer than this it is rejected. */ #define GFP_MIN_LENGTH 4 static void gfp_prompt(packet_info *pinfo, gchar* result) { snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "UPI %u as", GPOINTER_TO_UINT(p_get_proto_data(pinfo->pool, pinfo, proto_gfp, 0))); } static gpointer gfp_value(packet_info *pinfo) { return p_get_proto_data(pinfo->pool, pinfo, proto_gfp, 0); } /* GFP has several identical 16 bit CRCs in its header (HECs). Note that * this function increases the offset. */ static void gfp_add_hec_tree(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint *offset, const guint len, const int field, const int field_status, expert_field *ei_bad) { guint hec_calc; hec_calc = crc16_r3_ccitt_tvb(tvb, *offset, len); *offset += len; proto_tree_add_checksum(tree, tvb, *offset, field, field_status, ei_bad, pinfo, hec_calc, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY); *offset += 2; } /* G.7041 6.1.2 GFP payload area */ static void dissect_gfp_payload(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_tree *gfp_tree, guint *offset, guint payload_len) { tvbuff_t *payload_tvb; proto_item *type_ti = NULL; proto_item *fcs_ti; proto_tree *fcs_tree = NULL; guint pti, pfi, exi, upi; guint fcs, fcs_calc; guint fcs_len = 0; /* G.7041 6.1.2.3 Payload area scrambling * Note that payload when sent on the wire is scrambled as per ATM * with a 1 + x^43 multiplicative scrambler. Likely already removed by * the time we get a capture file (as with ATM). Could have a pref, * but if it's present we have to save state over subsequent frames, * always would fail to decode the first 43 payload bytes of a capture. */ /* G.7041 6.1.2.1 Payload Header - at least 4 bytes */ tvb_ensure_bytes_exist(tvb, *offset, 4); payload_len -= 4; /* G.7041 6.1.2.1.1 GFP type field - mandatory 2 bytes */ pti = tvb_get_bits8(tvb, 8*(*offset), 3); pfi = tvb_get_bits8(tvb, 8*(*offset)+3, 1); exi = tvb_get_bits8(tvb, 8*(*offset)+4, 4); upi = tvb_get_guint8(tvb, *offset+1); p_add_proto_data(pinfo->pool, pinfo, proto_gfp, 0, GUINT_TO_POINTER(upi)); col_add_str(pinfo->cinfo, COL_INFO, val_to_str(pti, gfp_pti_vals, "Reserved PTI (%d)")); if (pti == GFP_USER_DATA || pti == GFP_MANAGEMENT_COMMUNICATIONS) { /* G.7041 Table 6-3 - GFP_MANAGEMENT_COMMUNICATIONS * uses the same UPI table as USER_DATA, though * "not all of these UPI types are applicable" in that case. */ type_ti = proto_tree_add_bitmask_with_flags(gfp_tree, tvb, *offset, hf_gfp_type, ett_gfp_type, gfp_type_data_fields, ENC_BIG_ENDIAN, BMT_NO_FLAGS); col_append_sep_str(pinfo->cinfo, COL_INFO, ": ", rval_to_str(upi, gfp_upi_data_rvals, "Unknown 0x%02x")); } else if (pti == GFP_CLIENT_MANAGEMENT) { /* G.7041 Table 6-4 */ type_ti = proto_tree_add_bitmask_with_flags(gfp_tree, tvb, *offset, hf_gfp_type, ett_gfp_type, gfp_type_management_fields, ENC_BIG_ENDIAN, BMT_NO_FLAGS); col_append_sep_str(pinfo->cinfo, COL_INFO, ": ", rval_to_str(upi, gfp_upi_management_rvals, "Unknown 0x%02x")); } /* G.7041 6.1.2.1.2 Type HEC (tHEC) - mandatory 2 bytes */ gfp_add_hec_tree(tvb, pinfo, gfp_tree, offset, 2, hf_gfp_thec, hf_gfp_thec_status, &ei_gfp_thec_bad); switch (exi) { case GFP_EXT_NULL: /* G.7041 6.1.2.1.3.1 Null extension header */ break; case GFP_EXT_LINEAR: /* G.7041 6.1.2.1.3.2 Extension header for a linear frame */ if (payload_len < 4) { expert_add_info(pinfo, type_ti, &ei_gfp_exi_short); payload_len = 0; } else { payload_len -= 4; } proto_tree_add_item(gfp_tree, hf_gfp_cid, tvb, *offset, 1, ENC_BIG_ENDIAN); /* Next byte spare field, reserved */ /* 6.1.2.1.4 Extension HEC field */ gfp_add_hec_tree(tvb, pinfo, gfp_tree, offset, 2, hf_gfp_ehec, hf_gfp_ehec_status, &ei_gfp_ehec_bad); break; case GFP_EXT_RING: /* 6.1.2.1.3.3 Extension header for a ring frame */ /* "For further study." Undefined so fall through */ default: /* Reserved */ /* TODO: Mark as error / unhandled? */ break; } proto_item_set_end(gfp_tree, tvb, *offset); if (pfi == 1) { /* 6.1.2.2.1 Payload FCS field present */ if (payload_len < 4) { expert_add_info(pinfo, type_ti, &ei_gfp_pfi_short); fcs_len = payload_len; payload_len = 0; } else { fcs_len = 4; payload_len -= 4; } proto_tree_set_appendix(gfp_tree, tvb, *offset + payload_len, fcs_len); fcs = tvb_get_ntohl(tvb, *offset + payload_len); /* Same CRC32 as ATM */ /* As with ATM, we can either compute the CRC as it would be * calculated and compare (last step involves taking the complement), * or we can include the passed CRC in the input and check to see * if the remainder is a known value. I like the first method * only because it lets us display what we should have received. */ /* Method 1: */ fcs_calc = crc32_mpeg2_tvb_offset(tvb, *offset, payload_len); if (fcs == ~fcs_calc) { fcs_ti = proto_tree_add_uint_format_value(gfp_tree, hf_gfp_fcs, tvb, *offset+payload_len, 4, fcs, "0x%08x [correct]", fcs); fcs_tree = proto_item_add_subtree(fcs_ti, ett_gfp_fcs); fcs_ti = proto_tree_add_boolean(fcs_tree, hf_gfp_fcs_good, tvb, *offset+payload_len, 4, TRUE); proto_item_set_generated(fcs_ti); fcs_ti = proto_tree_add_boolean(fcs_tree, hf_gfp_fcs_bad, tvb, *offset+payload_len, 4, FALSE); proto_item_set_generated(fcs_ti); } else { fcs_ti = proto_tree_add_uint_format_value(gfp_tree, hf_gfp_fcs, tvb, *offset+payload_len, 4, fcs, "0x%08x [incorrect, should be 0x%08x]", fcs, fcs_calc); fcs_tree = proto_item_add_subtree(fcs_ti, ett_gfp_fcs); fcs_ti = proto_tree_add_boolean(fcs_tree, hf_gfp_fcs_good, tvb, *offset+payload_len, 4, FALSE); proto_item_set_generated(fcs_ti); fcs_ti = proto_tree_add_boolean(fcs_tree, hf_gfp_fcs_bad, tvb, *offset+payload_len, 4, TRUE); proto_item_set_generated(fcs_ti); expert_add_info(pinfo, fcs_ti, &ei_gfp_fcs_bad); } /* Method 2: */ /* fcs_calc = crc32_mpeg2_tvb_offset(tvb, *offset, payload_len+4); fcs_ti = proto_tree_add_uint(gfp_tree, hf_gfp_fcs, tvb, *offset+payload_len, 4, fcs); proto_item_append_text(fcs_ti, (fcs_calc == 0xC704DD7B) ? " [correct]" : " [incorrect]"); */ } /* Some client frames we can do. Others are not implemented yet. * Transparent mode types are much trickier than frame-mapped, * since they requires reassembling streams across multiple GFP packets. */ payload_tvb = tvb_new_subset_length(tvb, *offset, payload_len); switch (pti) { case GFP_USER_DATA: case GFP_MANAGEMENT_COMMUNICATIONS: if (!dissector_try_uint(gfp_dissector_table, upi, payload_tvb, pinfo, tree)) { expert_add_info_format(pinfo, type_ti, &ei_gfp_payload_undecoded, "Payload type 0x%02x (%s) unsupported", upi, rval_to_str_const(upi, gfp_upi_data_rvals, "UNKNOWN")); call_data_dissector(payload_tvb, pinfo, tree); } break; case GFP_CLIENT_MANAGEMENT: call_data_dissector(payload_tvb, pinfo, tree); break; default: break; } *offset += payload_len; *offset += fcs_len; } static int dissect_gfp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) { proto_item *ti, *pli_ti; proto_tree *gfp_tree; guint offset = 0; int len = 0; guint pli; /*** HEURISTICS ***/ /* Check that the packet is long enough for it to belong to us. */ if (tvb_reported_length(tvb) < GFP_MIN_LENGTH) return 0; /*** COLUMN DATA ***/ /* Set the Protocol column to the constant string of GFP */ col_set_str(pinfo->cinfo, COL_PROTOCOL, "GFP"); col_clear(pinfo->cinfo, COL_INFO); /* Avoid asserts for leaving these blank. */ col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "N/A"); col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A"); /*** PROTOCOL TREE ***/ /* create display subtree for the protocol */ ti = proto_tree_add_item(tree, proto_gfp, tvb, 0, GFP_MIN_LENGTH, ENC_NA); gfp_tree = proto_item_add_subtree(ti, ett_gfp); /* ITU-T G.7041 6.1.1 GFP core header */ /* The core header could be scrambled (see G.7041 6.1.1.3) but isn't on * the GFP level capture files I've seen as it's removed before then. * If using this as a subdissector to a SDH or OTN dissector, that could * be an issue. TODO: Maybe add a pref for scrambling? */ len = 2; pli_ti = proto_tree_add_item_ret_uint(gfp_tree, hf_gfp_pli, tvb, offset, len, ENC_BIG_ENDIAN, &pli); if (pli < 4) { /* Don't interpret as payload length */ proto_item_append_text(pli_ti, " (%s)", rval_to_str_const(pli, gfp_pli_rvals, "Unknown")); } col_set_str(pinfo->cinfo, COL_INFO, rval_to_str_const(pli, gfp_pli_rvals, "Unknown")); /* 6.1.1.2 Core HEC field */ gfp_add_hec_tree(tvb, pinfo, gfp_tree, &offset, len, hf_gfp_chec, hf_gfp_chec_status, &ei_gfp_chec_bad); if (pli == 0) { /* 6.2.1 GFP idle frames */ if (tvb_reported_length_remaining(tvb, offset)) { expert_add_info(pinfo, pli_ti, &ei_gfp_pli_idle_nonempty); } } else if (pli < 4) { /* 6.2.2 Other control frames (reserved) */ expert_add_info(pinfo, pli_ti, &ei_gfp_pli_unknown); } else { /* G.7041 6.1.2 GFP payload area */ if (tvb_reported_length(tvb) < pli + offset) { /* avoid signed / unsigned comparison */ proto_item_append_text(pli_ti, " (invalid, reported length is %u)", tvb_reported_length_remaining(tvb, offset)); expert_add_info(pinfo, pli_ti, &ei_gfp_pli_invalid); } dissect_gfp_payload(tvb, pinfo, tree, gfp_tree, &offset, pli); } /* Return the amount of data this dissector was able to dissect */ return offset; } void proto_register_gfp(void) { /* Setup list of header fields See Section 1.5 of README.dissector for * details. */ static hf_register_info hf[] = { { &hf_gfp_pli, { "Payload Length Indicator", "gfp.pli", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_chec, { "Core HEC", "gfp.chec", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_chec_status, { "cHEC Status", "gfp.chec.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, NULL, HFILL } }, { &hf_gfp_type, { "Type Field", "gfp.type", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_pti, { "PTI", "gfp.pti", FT_UINT16, BASE_HEX, VALS(gfp_pti_vals), 0xE000, "Payload Type Identifier", HFILL } }, { &hf_gfp_pfi, { "PFI", "gfp.pfi", FT_BOOLEAN, 16, TFS(&tfs_present_absent), 0x1000, "Payload FCS Indicator", HFILL } }, { &hf_gfp_exi, { "EXI", "gfp.exi", FT_UINT16, BASE_HEX, VALS(gfp_exi_vals), 0x0F00, "Extension Header Identifier", HFILL } }, { &hf_gfp_upi_data, { "UPI", "gfp.upi", FT_UINT16, BASE_HEX|BASE_RANGE_STRING, RVALS(gfp_upi_data_rvals), 0xFF, "User Payload Identifier for Client Data Frame (or Management Communications Frame)", HFILL } }, { &hf_gfp_upi_management, { "UPI", "gfp.upi", FT_UINT16, BASE_HEX|BASE_RANGE_STRING, RVALS(gfp_upi_management_rvals), 0xFF, "User Payload Identifier for Client Management Frame", HFILL } }, { &hf_gfp_thec, { "Type HEC", "gfp.thec", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_thec_status, { "tHEC Status", "gfp.thec.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, NULL, HFILL } }, { &hf_gfp_cid, { "Channel ID", "gfp.cid", FT_UINT8, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_ehec, { "Extension HEC", "gfp.ehec", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_ehec_status, { "eHEC Status", "gfp.ehec.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, NULL, HFILL } }, { &hf_gfp_fcs, { "Payload FCS", "gfp.fcs", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_gfp_fcs_good, { "Good FCS", "gfp.fcs_good", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "True: FCS matches payload; False: doesn't match", HFILL } }, { &hf_gfp_fcs_bad, { "Bad eHEC", "gfp.fcs_bad", FT_BOOLEAN, BASE_NONE, NULL, 0x0, "True: FCS doesn't match payload; False: matches", HFILL } } }; /* Setup protocol subtree array */ static gint *ett[] = { &ett_gfp, &ett_gfp_type, &ett_gfp_fcs }; /* Setup protocol expert items */ static ei_register_info ei[] = { { &ei_gfp_pli_idle_nonempty, { "gfp.pli.idle.nonempty", PI_MALFORMED, PI_ERROR, "Payload present on idle frame", EXPFILL } }, { &ei_gfp_pli_unknown, { "gfp.pli.unknown", PI_UNDECODED, PI_WARN, "Unknown control frame type", EXPFILL } }, { &ei_gfp_pli_invalid, { "gfp.pli.invalid", PI_MALFORMED, PI_WARN, "Bogus PLI does not match reported length", EXPFILL } }, { &ei_gfp_chec_bad, { "gfp.chec.bad", PI_CHECKSUM, PI_WARN, "Bad cHEC", EXPFILL } }, { &ei_gfp_thec_bad, { "gfp.thec.bad", PI_CHECKSUM, PI_WARN, "Bad tHEC", EXPFILL } }, { &ei_gfp_ehec_bad, { "gfp.ehec.bad", PI_CHECKSUM, PI_WARN, "Bad eHEC", EXPFILL } }, { &ei_gfp_exi_short, { "gfp.exi.missing", PI_MALFORMED, PI_ERROR, "EXI bit set but PLI too short for extension header", EXPFILL} }, { &ei_gfp_pfi_short, { "gfp.pfi.missing", PI_MALFORMED, PI_ERROR, "PFI bit set but PLI too short for payload FCS", EXPFILL} }, { &ei_gfp_payload_undecoded, { "gfp.payload.undecoded", PI_UNDECODED, PI_WARN, "Payload type not supported yet by the dissector", EXPFILL} }, { &ei_gfp_fcs_bad, { "gfp.fcs.bad", PI_CHECKSUM, PI_WARN, "Bad FCS", EXPFILL } } }; /* Decode As handling */ static build_valid_func gfp_da_build_value[1] = {gfp_value}; static decode_as_value_t gfp_da_values = {gfp_prompt, 1, gfp_da_build_value}; static decode_as_t gfp_da = {"gfp", "gfp.upi", 1, 0, &gfp_da_values, NULL, NULL, decode_as_default_populate_list, decode_as_default_reset, decode_as_default_change, NULL}; /* module_t *gfp_module; */ expert_module_t *expert_gfp; /* Register the protocol name and description */ proto_gfp = proto_register_protocol("Generic Framing Procedure", "GFP", "gfp"); gfp_handle = register_dissector("gfp", dissect_gfp, proto_gfp); /* Required function calls to register the header fields and subtrees */ proto_register_field_array(proto_gfp, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); /* Required function calls to register expert items */ expert_gfp = expert_register_protocol(proto_gfp); expert_register_field_array(expert_gfp, ei, array_length(ei)); /* Subdissectors for payload */ gfp_dissector_table = register_dissector_table("gfp.upi", "GFP UPI (for Client Data frames)", proto_gfp, FT_UINT8, BASE_DEC); /* Don't register a preferences module yet since there are no prefs in * order to avoid a warning. (See section 2.6 of README.dissector * for more details on preferences). */ /*gfp_module = prefs_register_protocol(proto_gfp, NULL);*/ register_decode_as(&gfp_da); } void proto_reg_handoff_gfp(void) { dissector_add_uint("wtap_encap", WTAP_ENCAP_GFP_T, gfp_handle); dissector_add_uint("wtap_encap", WTAP_ENCAP_GFP_F, gfp_handle); /* Add a few of the easiest UPIs to decode. There's more that probably * would work, but are untested (frame mapped DVB, frame mapped Fibre * Channel). The transparent mode ones are trickier, since without a * one-to-one mapping of frames, we would have to reassemble payload * packets across multiple GFP packets. * * Section 7.1.1 "Ethernet MAC encapsulation" of G.7041 says * "The Ethernet MAC octets from destination address through * "frame check sequence, inclusive, are placed in the GFP payload * "information field.", so we want the dissector for Ethernet * frames including the FCS. */ dissector_add_uint("gfp.upi", 1, find_dissector("eth_withfcs")); dissector_add_uint("gfp.upi", 2, find_dissector("ppp_hdlc")); dissector_add_uint("gfp.upi", 9, find_dissector("mp2t")); dissector_add_uint("gfp.upi", 12, find_dissector("mpls")); dissector_add_uint("gfp.upi", 13, find_dissector("mpls")); dissector_add_uint("gfp.upi", 16, find_dissector("ip")); dissector_add_uint("gfp.upi", 17, find_dissector("ipv6")); } /* * 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: */