/* packet-redback.c * * Wireshark - Network traffic analyzer * By Gerald Combs * * Ericsson SmartEdge tcpdump trace disassembly * Copyright 2005-2014 Florian Lohoff * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include void proto_register_redback(void); void proto_reg_handoff_redback(void); static dissector_handle_t redback_handle; static int ett_redback; static dissector_table_t osinl_incl_subdissector_table; static dissector_table_t osinl_excl_subdissector_table; static dissector_handle_t ipv4_handle; static dissector_handle_t ipv6_handle; static dissector_handle_t ethnofcs_handle; static dissector_handle_t clnp_handle; static dissector_handle_t arp_handle; static dissector_handle_t ppp_handle; static dissector_handle_t ppphdlc_handle; static int proto_redback; static int hf_redback_circuit; static int hf_redback_context; static int hf_redback_dataoffset; static int hf_redback_flags; static int hf_redback_l3offset; static int hf_redback_length; static int hf_redback_padding; static int hf_redback_protocol; static int hf_redback_unknown; static expert_field ei_redback_protocol; static int dissect_redback(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { uint16_t l3off, dataoff, proto; proto_item *ti, *protocol_item; proto_tree *rbtree = NULL; tvbuff_t *next_tvb; col_set_str(pinfo->cinfo,COL_PROTOCOL,"RBN"); dataoff = tvb_get_ntohs(tvb, 20); l3off = tvb_get_ntohs(tvb, 22); ti = proto_tree_add_item(tree, proto_redback, tvb, 0, -1, ENC_NA); rbtree = proto_item_add_subtree(ti, ett_redback); proto_tree_add_item(rbtree, hf_redback_context, tvb, 0, 4, ENC_BIG_ENDIAN); proto_tree_add_item(rbtree, hf_redback_flags, tvb, 4, 4, ENC_BIG_ENDIAN); proto_tree_add_item(rbtree, hf_redback_circuit, tvb, 8, 8, ENC_BIG_ENDIAN); proto_tree_add_item(rbtree, hf_redback_length, tvb, 16, 2, ENC_BIG_ENDIAN); protocol_item = proto_tree_add_item(rbtree, hf_redback_protocol, tvb, 18, 2, ENC_BIG_ENDIAN); proto_tree_add_item(rbtree, hf_redback_dataoffset, tvb, 20, 2, ENC_BIG_ENDIAN); proto_tree_add_item(rbtree, hf_redback_l3offset, tvb, 22, 2, ENC_BIG_ENDIAN); if (dataoff > 24) { proto_tree_add_item(rbtree, hf_redback_padding, tvb, 24, dataoff-24, ENC_NA); } proto = tvb_get_ntohs(tvb, 18); switch(proto) { case 0x01: /* * IP on Ethernet - Incoming data points to an ethernet header * outgoing we have a pure IPv4 Packet */ next_tvb = tvb_new_subset_remaining(tvb, dataoff); if (dataoff == l3off) call_dissector(ipv4_handle, next_tvb, pinfo, tree); else if (dataoff+2 == l3off) call_dissector(ppp_handle, next_tvb, pinfo, tree); else if (dataoff+4 == l3off) call_dissector(ppphdlc_handle, next_tvb, pinfo, tree); else call_dissector(ethnofcs_handle, next_tvb, pinfo, tree); break; case 0x02: /* * This is ISIS - Either incoming with ethernet FCS * and CLNP - passed to the eth dissector or in case * of outgoing it's pure ISIS and the linecard attaches * the ethernet and CLNP headers ... * */ next_tvb = tvb_new_subset_remaining(tvb, dataoff); if (l3off > dataoff) { call_dissector(ethnofcs_handle, next_tvb, pinfo, tree); } else { uint8_t nlpid = tvb_get_uint8(tvb, dataoff); if(dissector_try_uint(osinl_incl_subdissector_table, nlpid, next_tvb, pinfo, tree)) break; next_tvb = tvb_new_subset_remaining(tvb, dataoff+1); if(dissector_try_uint(osinl_excl_subdissector_table, nlpid, next_tvb, pinfo, tree)) break; next_tvb = tvb_new_subset_remaining(tvb, dataoff); call_data_dissector(next_tvb, pinfo, tree); } break; case 0x06: { /* * PPP Messages e.g. LCP, IPCP etc - possibly on ethernet in case of PPPoE. * PPPoE messages are Protocol 8 ... */ uint32_t flags; flags = tvb_get_ntohl(tvb, 4); if (flags & 0x04000000) { next_tvb = tvb_new_subset_remaining(tvb, dataoff); } else { if (tree) proto_tree_add_item(rbtree, hf_redback_unknown, tvb, dataoff, 4, ENC_NA); next_tvb = tvb_new_subset_remaining(tvb, dataoff+4); } if (l3off == dataoff) { call_dissector(ppp_handle, next_tvb, pinfo, tree); } else { call_dissector(ethnofcs_handle, next_tvb, pinfo, tree); } break; } case 0x03: /* Unicast Ethernet tx - Seen with PPPoE PADO */ case 0x04: /* Unicast Ethernet rx - Seen with ARP */ case 0x08: /* Broadcast Ethernet rx - Seen with PPPoE PADI */ next_tvb = tvb_new_subset_remaining(tvb, dataoff); call_dissector(ethnofcs_handle, next_tvb, pinfo, tree); break; case 0x09: /* IPv6 either encapsulated as ethernet or native ip */ next_tvb = tvb_new_subset_remaining(tvb, dataoff); if (dataoff == l3off) call_dissector(ipv6_handle, next_tvb, pinfo, tree); else call_dissector(ethnofcs_handle, next_tvb, pinfo, tree); break; default: expert_add_info(pinfo, protocol_item, &ei_redback_protocol); break; } return tvb_captured_length(tvb); } void proto_register_redback(void) { static hf_register_info hf[] = { { &hf_redback_context, { "Context", "redback.context", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_redback_flags, { "Flags", "redback.flags", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_redback_circuit, { "Circuit", "redback.circuit", FT_UINT64, BASE_HEX, NULL, 0x0, NULL, HFILL } }, { &hf_redback_length, { "Length", "redback.length", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_redback_protocol, { "Protocol", "redback.protocol", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_redback_l3offset, { "Layer 3 Offset", "redback.l3offset", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_redback_dataoffset, { "Data Offset", "redback.dataoffset", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL } }, { &hf_redback_padding, { "Padding", "redback.padding", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, { &hf_redback_unknown, { "Unknown", "redback.unknown", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL } }, }; static int *ett[] = { &ett_redback }; static ei_register_info ei[] = { { &ei_redback_protocol, { "redback.protocol.unknown", PI_PROTOCOL, PI_WARN, "Unknown Protocol Data", EXPFILL }}, }; expert_module_t* expert_redback; proto_redback = proto_register_protocol("Redback", "Redback", "redback"); proto_register_field_array(proto_redback, hf, array_length(hf)); redback_handle = register_dissector("redback", dissect_redback, proto_redback); proto_register_subtree_array(ett, array_length(ett)); expert_redback = expert_register_protocol(proto_redback); expert_register_field_array(expert_redback, ei, array_length(ei)); } void proto_reg_handoff_redback(void) { osinl_incl_subdissector_table = find_dissector_table("osinl.incl"); osinl_excl_subdissector_table = find_dissector_table("osinl.excl"); ipv4_handle = find_dissector_add_dependency("ip", proto_redback); ipv6_handle = find_dissector_add_dependency("ipv6", proto_redback); ethnofcs_handle = find_dissector_add_dependency("eth_withoutfcs", proto_redback); clnp_handle = find_dissector_add_dependency("clnp", proto_redback); arp_handle = find_dissector_add_dependency("arp", proto_redback); ppp_handle = find_dissector_add_dependency("ppp", proto_redback); ppphdlc_handle = find_dissector_add_dependency("ppp_hdlc", proto_redback); dissector_add_uint("wtap_encap", WTAP_ENCAP_REDBACK, redback_handle); } /* * Editor modelines - https://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 8 * tab-width: 8 * indent-tabs-mode: t * End: * * vi: set shiftwidth=8 tabstop=8 noexpandtab: * :indentSize=8:tabSize=8:noTabs=false: */