diff options
Diffstat (limited to 'epan/dissectors/packet-trill.c')
| -rw-r--r-- | epan/dissectors/packet-trill.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/epan/dissectors/packet-trill.c b/epan/dissectors/packet-trill.c new file mode 100644 index 00000000..755b272e --- /dev/null +++ b/epan/dissectors/packet-trill.c @@ -0,0 +1,217 @@ +/* packet-trill.c + * Routines for TRILL (TRansparent Interconnection of Lots of Links) dissection + * Copyright 2010, David Bond <mokon@mokon.net> + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +/* + * See: RFC6325 + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/etypes.h> + +void proto_register_trill(void); +void proto_reg_handoff_trill(void); + +static dissector_handle_t trill_handle; + +static int proto_trill = -1 ; +static gint ett_trill = -1 ; + +static int hf_trill_version = -1 ; +static int hf_trill_reserved = -1 ; +static int hf_trill_multi_dst = -1 ; +static int hf_trill_op_len = -1 ; +static int hf_trill_hop_cnt = -1 ; +static int hf_trill_egress_nick = -1 ; +static int hf_trill_ingress_nick = -1 ; +/* TODO For now we will just add all the options into a byte field. + Later this should be parsed out into a sub-tree with all the option + details. */ +static int hf_trill_options= -1 ; + +static dissector_handle_t eth_dissector ; + +#define TRILL_VERSION_MASK 0xC000 +#define TRILL_RESERVED_MASK 0x3000 +#define TRILL_MULTI_DST_MASK 0x0800 +#define TRILL_OP_LEN_MASK 0x07C0 +#define TRILL_HOP_CNT_MASK 0x003F + +#define TRILL_PROTO_COL_NAME "TRILL" +#define TRILL_PROTO_COL_INFO "TRILL Encapsulated Frame" + +#define TRILL_MIN_FRAME_LENGTH 6 +#define TRILL_BIT_FIELDS_LEN 2 +#define TRILL_NICKNAME_LEN 2 +#define TRILL_OP_LENGTH_BYTE_UNITS 0x4 + +static const true_false_string multi_dst_strings = { + "Multi-Destination TRILL Frame", + "Known Unicast TRILL Frame" +} ; + +static const range_string version_strings[] = { + { 0, 0, "RFC6325 Version" }, + { 1, 3, "Unallocated Version" }, + { 0, 0, NULL } +} ; + +static const range_string reserved_strings[] = { + { 0, 0, "Legal Value" }, + { 1, 3, "Illegal Value" }, + { 0, 0, NULL } +} ; + +static const range_string nickname_strings[] = { + { 0x0000, 0x0000, "Nickname Not Specified" }, + { 0x0001, 0xFFBF, "Valid Nickname" }, + { 0xFFC0, 0xFFC0, "Any RBridge" }, + { 0xFFC1, 0xFFC1, "OOMF" }, + { 0xFFC2, 0xFFFE, "Reserved for Future Specification" }, + { 0xFFFF, 0xFFFF, "Permanently Reserved" }, + { 0, 0, NULL } +} ; + +/* Trill Dissector */ +static int +dissect_trill( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_ ) +{ + proto_item *ti ; + proto_tree *trill_tree ; + guint32 op_len ; + tvbuff_t *next_tvb ; + int offset = 0 ; + + col_set_str( pinfo->cinfo, COL_PROTOCOL, TRILL_PROTO_COL_NAME ) ; + col_set_str( pinfo->cinfo, COL_INFO, TRILL_PROTO_COL_INFO ) ; + + op_len = tvb_get_bits( tvb, 5, 5, ENC_BIG_ENDIAN ) * TRILL_OP_LENGTH_BYTE_UNITS ; + if (tree) { + ti = proto_tree_add_item( tree, proto_trill, tvb, 0, + TRILL_MIN_FRAME_LENGTH + op_len, ENC_NA ) ; + trill_tree = proto_item_add_subtree( ti, ett_trill ) ; + + /* Parse the bit fields, i.e. V, R, M, Op-Length, Hop Count. */ + proto_tree_add_item( trill_tree, hf_trill_version, tvb, offset, + TRILL_BIT_FIELDS_LEN, ENC_BIG_ENDIAN ) ; + proto_tree_add_item( trill_tree, hf_trill_reserved, tvb, offset, + TRILL_BIT_FIELDS_LEN, ENC_BIG_ENDIAN ) ; + proto_tree_add_item( trill_tree, hf_trill_multi_dst, tvb, offset, + TRILL_BIT_FIELDS_LEN, ENC_BIG_ENDIAN ) ; + proto_tree_add_item( trill_tree, hf_trill_op_len, tvb, offset, + TRILL_BIT_FIELDS_LEN, ENC_BIG_ENDIAN ) ; + proto_tree_add_item( trill_tree, hf_trill_hop_cnt, tvb, offset, + TRILL_BIT_FIELDS_LEN, ENC_BIG_ENDIAN ) ; + + /* Parse the egress nickname. */ + offset += TRILL_BIT_FIELDS_LEN ; + proto_tree_add_item( trill_tree, hf_trill_egress_nick, tvb, offset, + TRILL_NICKNAME_LEN, ENC_BIG_ENDIAN ) ; + + /* Parse the ingress nickname. */ + offset += TRILL_NICKNAME_LEN ; + proto_tree_add_item( trill_tree, hf_trill_ingress_nick, tvb, offset, + TRILL_NICKNAME_LEN , ENC_BIG_ENDIAN ) ; + + /* Parse the options field. */ + offset += TRILL_NICKNAME_LEN ; + if( op_len != 0 ) { + proto_tree_add_item( trill_tree, hf_trill_options, tvb, + offset, op_len, ENC_NA ) ; + } + } + + /* call the eth dissector */ + next_tvb = tvb_new_subset_remaining( tvb, TRILL_MIN_FRAME_LENGTH + op_len ) ; + call_dissector( eth_dissector, next_tvb, pinfo, tree ) ; + + return tvb_reported_length( tvb ) ; +} + +/* Register the protocol with Wireshark */ +void +proto_register_trill(void) +{ + static hf_register_info hf[] = { + { &hf_trill_version, + { "Version", "trill.version", + FT_UINT16, BASE_DEC_HEX|BASE_RANGE_STRING, RVALS(version_strings), + TRILL_VERSION_MASK, "The TRILL version number.", HFILL }}, + { &hf_trill_reserved, + { "Reserved", "trill.reserved", + FT_UINT16, BASE_DEC_HEX|BASE_RANGE_STRING, RVALS(reserved_strings), + TRILL_RESERVED_MASK, "Bits reserved for future specification.", HFILL }}, + { &hf_trill_multi_dst, + { "Multi Destination", "trill.multi_dst", + FT_BOOLEAN, 16, TFS(&multi_dst_strings), TRILL_MULTI_DST_MASK, + "A boolean specifying if this is a multi-destination frame.", HFILL }}, + { &hf_trill_op_len, + { "Option Length", "trill.op_len", + FT_UINT16, BASE_DEC_HEX, NULL, TRILL_OP_LEN_MASK, + "The length of the options field of this frame.", HFILL }}, + { &hf_trill_hop_cnt, + { "Hop Count", "trill.hop_cnt", + FT_UINT16, BASE_DEC_HEX, NULL, TRILL_HOP_CNT_MASK, + "The remaining hop count for this frame.", HFILL }}, + { &hf_trill_egress_nick, + { "Egress/Root RBridge Nickname", "trill.egress_nick", + FT_UINT16, BASE_DEC_HEX|BASE_RANGE_STRING, RVALS(nickname_strings), 0x0, + "The Egress or Distribution Tree Root RBridge Nickname.", HFILL }}, + { &hf_trill_ingress_nick, + { "Ingress RBridge Nickname", "trill.ingress_nick", + FT_UINT16, BASE_DEC_HEX|BASE_RANGE_STRING, RVALS(nickname_strings), 0x0, + "The Ingress RBridge Nickname.", HFILL }}, + { &hf_trill_options, + { "Options", "trill.options", + FT_BYTES, BASE_NONE, NULL, 0x0, + "The TRILL Options field.", HFILL }} + }; + + static gint *ett[] = { + &ett_trill + }; + + proto_trill = proto_register_protocol("TRILL", "TRILL", "trill"); + proto_register_field_array(proto_trill, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + trill_handle = register_dissector("trill", dissect_trill, proto_trill); +} + +void +proto_reg_handoff_trill(void) +{ + dissector_add_uint("ethertype", ETHERTYPE_TRILL, trill_handle); + + /* + * RFC 6325, section 4.1.4 "Frame Check Sequence (FCS)", says + * + * "Thus, when a frame is encapsulated, the original FCS is not + * included but is discarded." + * + * meaning that the inner Ethernet frame does *not* include an + * FCS. + */ + eth_dissector = find_dissector_add_dependency( "eth_withoutfcs", proto_trill ); +} + +/* + * 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: + */ |