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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-10 20:34:10 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-10 20:34:10 +0000 |
commit | e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc (patch) | |
tree | 68cb5ef9081156392f1dd62a00c6ccc1451b93df /epan/dissectors/packet-dtp.c | |
parent | Initial commit. (diff) | |
download | wireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.tar.xz wireshark-e4ba6dbc3f1e76890b22773807ea37fe8fa2b1bc.zip |
Adding upstream version 4.2.2.upstream/4.2.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'epan/dissectors/packet-dtp.c')
-rw-r--r-- | epan/dissectors/packet-dtp.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/epan/dissectors/packet-dtp.c b/epan/dissectors/packet-dtp.c new file mode 100644 index 0000000..5d49c95 --- /dev/null +++ b/epan/dissectors/packet-dtp.c @@ -0,0 +1,374 @@ +/* packet-dtp.c + * Routines for the disassembly for Cisco Dynamic Trunk Protocol + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * DTP support added by Charlie Lenahan <clenahan@fortresstech.com> + * + * Additional information comes from Yersinia (http://www.yersinia.net/) + * by Alfredo Andres and David Barroso + * + * Improved dissection for Trunk Status and Trunk Type TLVs + * based on DTP description in U.S. Patent #6,445,715 and + * consultations with Aninda Chatterjee @ Cisco + * by Peter Paluch <Peter.Paluch@fri.uniza.sk> + * + * SPDX-License-Identifier: GPL-2.0-or-later + * + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/to_str.h> +#include <epan/expert.h> +#include <epan/cisco_pid.h> + +/* + * It's incomplete, and it appears to be inaccurate in a number of places, + * but it's all I could find.... + */ +void proto_register_dtp(void); +void proto_reg_handoff_dtp(void); + +static dissector_handle_t dtp_handle; + +static int proto_dtp = -1; +static int hf_dtp_version = -1; +static int hf_dtp_domain = -1; +static int hf_dtp_tlvtype = -1; +static int hf_dtp_tlvlength = -1; +static int hf_dtp_senderid = -1; +static int hf_dtp_tot = -1; +static int hf_dtp_tat = -1; +static int hf_dtp_tos = -1; +static int hf_dtp_tas = -1; +static int hf_dtp_data = -1; + +static gint ett_dtp = -1; +static gint ett_dtp_tlv = -1; +static gint ett_dtp_status = -1; +static gint ett_dtp_type = -1; + +static expert_field ei_dtp_tlv_length_too_short = EI_INIT; +static expert_field ei_dtp_tlv_length_invalid = EI_INIT; +static expert_field ei_dtp_truncated = EI_INIT; + +static void +dissect_dtp_tlv(packet_info *pinfo, tvbuff_t *tvb, int offset, int length, + proto_tree *tree, proto_item *ti, proto_item *tlv_length_item, guint8 type); + + +#define DTP_TLV_DOMAIN 0x01 /* VTP Domain Name */ +#define DTP_TLV_TRSTATUS 0x02 /* Trunk Status */ +#define DTP_TLV_TRTYPE 0x03 /* Trunk Type */ +#define DTP_TLV_SENDERID 0x04 /* Sender ID (MAC) */ + +#define DTP_TOS_SHIFT 7 +#define DTP_TOT_SHIFT 5 + +#define DTP_TOS_MASK 0x80 +#define DTP_TAS_MASK 0x07 + +#define DTP_TOT_MASK 0xE0 +#define DTP_TAT_MASK 0x07 + +#define DTP_TOSVALUE(status) (((status) & DTP_TOS_MASK) >> DTP_TOS_SHIFT) +#define DTP_TASVALUE(status) ((status) & DTP_TAS_MASK) + +#define DTP_TOTVALUE(type) (((type) & DTP_TOT_MASK) >> DTP_TOT_SHIFT) +#define DTP_TATVALUE(type) ((type) & DTP_TAT_MASK) + +/* Trunk Operating Status */ +#define DTP_TOS_ACCESS 0x0 +#define DTP_TOS_TRUNK 0x1 + +/* Trunk Administrative Status */ +#define DTP_TAS_ON 0x1 +#define DTP_TAS_OFF 0x2 +#define DTP_TAS_DESIRABLE 0x3 +#define DTP_TAS_AUTO 0x4 + +/* Trunk Operating Type */ +#define DTP_TOT_NATIVE 0x1 +#define DTP_TOT_ISL 0x2 +#define DTP_TOT_DOT1Q 0x5 + +/* Trunk Administrative Type */ +#define DTP_TAT_NEGOTIATED 0x0 +#define DTP_TAT_NATIVE 0x1 +#define DTP_TAT_ISL 0x2 +#define DTP_TAT_DOT1Q 0x5 + + +static const value_string dtp_tlv_type_vals[] = { + { DTP_TLV_DOMAIN, "Domain" }, + { DTP_TLV_TRSTATUS, "Trunk Status" }, + { DTP_TLV_TRTYPE, "Trunk Type" }, + { DTP_TLV_SENDERID, "Sender ID" }, + + { 0, NULL } +}; + +static const value_string dtp_tos_vals[] = { + { DTP_TOS_ACCESS, "Access" }, + { DTP_TOS_TRUNK, "Trunk"}, + + { 0, NULL } +}; + +static const value_string dtp_tas_vals[] = { + { DTP_TAS_ON, "On" }, + { DTP_TAS_OFF, "Off" }, + { DTP_TAS_DESIRABLE, "Desirable" }, + { DTP_TAS_AUTO, "Auto" }, + + { 0, NULL } +}; + +static const value_string dtp_tot_vals[] = { + { DTP_TOT_NATIVE, "Native" }, + { DTP_TOT_ISL, "ISL" }, + { DTP_TOT_DOT1Q, "802.1Q" }, + + { 0, NULL } +}; + +static const value_string dtp_tat_vals[] = { + { DTP_TAT_NEGOTIATED, "Negotiated" }, + { DTP_TAT_NATIVE, "Native" }, + { DTP_TAT_ISL, "ISL" }, + { DTP_TAT_DOT1Q, "802.1Q" }, + + { 0, NULL } +}; + +static int +dissect_dtp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) +{ + proto_item *ti; + proto_tree *dtp_tree; + proto_tree *tlv_tree; + int offset = 0; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "DTP"); + col_set_str(pinfo->cinfo, COL_INFO, "Dynamic Trunk Protocol"); + + ti = proto_tree_add_item(tree, proto_dtp, tvb, offset, -1, ENC_NA); + dtp_tree = proto_item_add_subtree(ti, ett_dtp); + + /* We assume version */ + proto_tree_add_item(dtp_tree, hf_dtp_version, tvb, offset, 1, ENC_BIG_ENDIAN); + offset += 1; + + while (tvb_reported_length_remaining(tvb, offset) > 0) { + int type, length, valuelength; + proto_item * tlv_length_item; + + /* XXX - why not just let tvbuff exceptions handle this? */ + if (tvb_reported_length_remaining(tvb, offset) < 4) { + expert_add_info(pinfo, dtp_tree, &ei_dtp_truncated); + break; + } + + type = tvb_get_ntohs(tvb, offset); + length = tvb_get_ntohs(tvb, offset + 2); + + tlv_tree = proto_tree_add_subtree(dtp_tree, tvb, offset, length, ett_dtp_tlv, NULL, + val_to_str(type, dtp_tlv_type_vals, "Unknown TLV type: 0x%02x")); + + proto_tree_add_uint(tlv_tree, hf_dtp_tlvtype, tvb, offset, 2, type); + offset+=2; + + tlv_length_item = proto_tree_add_uint(tlv_tree, hf_dtp_tlvlength, tvb, offset, 2, length); + offset+=2; + + if (length <= 4) { + /* Length includes type and length fields, so it + must be >= 4, and no known TLVs have a value + length of 0, so it must be > 4. */ + expert_add_info(pinfo, tlv_length_item, &ei_dtp_tlv_length_too_short); + break; + } + valuelength = (length-4); + dissect_dtp_tlv(pinfo, tvb, offset, valuelength, tlv_tree, ti, tlv_length_item, (guint8) type); + offset += valuelength; + } + return tvb_captured_length(tvb); +} + +static void +dissect_dtp_tlv(packet_info *pinfo, tvbuff_t *tvb, int offset, int length, + proto_tree *tree, proto_item *ti, proto_item *tlv_length_item, guint8 type) +{ + switch (type) { + + case DTP_TLV_DOMAIN: + if (length <= 33) { /* VTP domain name is at most 32 bytes long and is null-terminated */ + proto_item_append_text(ti, ": %s", tvb_format_text(pinfo->pool, tvb, offset, length - 1)); + proto_tree_add_item(tree, hf_dtp_domain, tvb, offset, length, ENC_ASCII); + } + else + expert_add_info(pinfo, tlv_length_item, &ei_dtp_tlv_length_invalid); + + break; + + case DTP_TLV_TRSTATUS: + if (length == 1) { /* Value field length must be 1 byte */ + proto_tree * field_tree = NULL; + guint8 trunk_status = tvb_get_guint8(tvb, offset); + + proto_item_append_text(ti, + " (Operating/Administrative): %s/%s (0x%02x)", + val_to_str_const(DTP_TOSVALUE(trunk_status), dtp_tos_vals, "Unknown operating status"), + val_to_str_const(DTP_TASVALUE(trunk_status), dtp_tas_vals, "Unknown administrative status"), + trunk_status); + field_tree = proto_tree_add_subtree_format(tree, tvb, offset, length, ett_dtp_status, NULL, "Value: %s/%s (0x%02x)", + val_to_str_const(DTP_TOSVALUE(trunk_status), dtp_tos_vals, "Unknown operating status"), + val_to_str_const(DTP_TASVALUE(trunk_status), dtp_tas_vals, "Unknown administrative status"), + trunk_status); + proto_tree_add_item(field_tree, hf_dtp_tos, tvb, offset, length, ENC_BIG_ENDIAN); + proto_tree_add_item(field_tree, hf_dtp_tas, tvb, offset, length, ENC_BIG_ENDIAN); + } + else + expert_add_info(pinfo, tlv_length_item, &ei_dtp_tlv_length_invalid); + + break; + + case DTP_TLV_TRTYPE: + if (length == 1) { /* Value field length must be 1 byte */ + proto_tree * field_tree; + guint8 trunk_type = tvb_get_guint8(tvb, offset); + proto_item_append_text(ti, + " (Operating/Administrative): %s/%s (0x%02x)", + val_to_str_const(DTP_TOTVALUE(trunk_type), dtp_tot_vals, "Unknown operating type"), + val_to_str_const(DTP_TATVALUE(trunk_type), dtp_tat_vals, "Unknown administrative type"), + trunk_type); + field_tree = proto_tree_add_subtree_format(tree, tvb, offset, length, ett_dtp_type, NULL, "Value: %s/%s (0x%02x)", + val_to_str_const(DTP_TOTVALUE(trunk_type), dtp_tot_vals, "Unknown operating type"), + val_to_str_const(DTP_TATVALUE(trunk_type), dtp_tat_vals, "Unknown administrative type"), + trunk_type); + proto_tree_add_item(field_tree, hf_dtp_tot, tvb, offset, length, ENC_BIG_ENDIAN); + proto_tree_add_item(field_tree, hf_dtp_tat, tvb, offset, length, ENC_BIG_ENDIAN); + } + else + expert_add_info(pinfo, tlv_length_item, &ei_dtp_tlv_length_invalid); + + break; + + case DTP_TLV_SENDERID: + if (length == 6) { /* Value length must be 6 bytes for a MAC address */ + proto_item_append_text(ti, ": %s", + tvb_ether_to_str(pinfo->pool, tvb, offset)); /* XXX - resolve? */ + proto_tree_add_item(tree, hf_dtp_senderid, tvb, offset, length, ENC_NA); + } + else + expert_add_info(pinfo, tlv_length_item, &ei_dtp_tlv_length_invalid); + + break; + + default: + proto_tree_add_item(tree, hf_dtp_data, tvb, offset, length, ENC_NA); + break; + } +} + +void +proto_register_dtp(void) +{ + static hf_register_info hf[] = { + { &hf_dtp_version, + { "Version", "dtp.version", FT_UINT8, BASE_DEC, + NULL, 0x0, NULL, HFILL }}, + + { &hf_dtp_domain, + { "Domain", "dtp.domain", FT_STRING, BASE_NONE, + NULL, 0x0, NULL, HFILL }}, + + { &hf_dtp_tlvtype, + { "Type", "dtp.tlv_type", FT_UINT16, BASE_HEX, + VALS(dtp_tlv_type_vals), 0x0, NULL, HFILL }}, + + { &hf_dtp_tlvlength, + { "Length", "dtp.tlv_len", FT_UINT16, BASE_DEC, + NULL, 0x0, NULL, HFILL }}, + + { &hf_dtp_tos, + { "Trunk Operating Status", "dtp.tos", FT_UINT8, BASE_HEX, + VALS(dtp_tos_vals), DTP_TOS_MASK, NULL, HFILL }}, + + { &hf_dtp_tas, + { "Trunk Administrative Status", "dtp.tas", FT_UINT8, BASE_HEX, + VALS(dtp_tas_vals), DTP_TAS_MASK, NULL, HFILL }}, + + { &hf_dtp_tot, + { "Trunk Operating Type", "dtp.tot", FT_UINT8, BASE_HEX, + VALS(dtp_tot_vals), DTP_TOT_MASK, NULL, HFILL }}, + + { &hf_dtp_tat, + { "Trunk Administrative Type", "dtp.tat", FT_UINT8, BASE_HEX, + VALS(dtp_tat_vals), DTP_TAT_MASK, NULL, HFILL }}, + + { &hf_dtp_senderid, + { "Sender ID", "dtp.senderid", FT_ETHER, BASE_NONE, + NULL, 0x0, "MAC Address of neighbor", HFILL }}, + + { &hf_dtp_data, + { "Data", "dtp.data", FT_ETHER, BASE_NONE, + NULL, 0x0, NULL, HFILL }}, + }; + + static gint *ett[] = { + &ett_dtp, + &ett_dtp_tlv, + &ett_dtp_status, + &ett_dtp_type, + }; + + static ei_register_info ei[] = { + { &ei_dtp_tlv_length_too_short, + { "dtp.tlv_len.too_short", PI_MALFORMED, PI_ERROR, + "Indicated length is less than the minimum length", EXPFILL }}, + + { &ei_dtp_tlv_length_invalid, + { "dtp.tlv_len.invalid", PI_MALFORMED, PI_ERROR, + "Indicated length does not correspond to this record type", EXPFILL }}, + + { &ei_dtp_truncated, + { "dtp.truncated", PI_MALFORMED, PI_ERROR, + "DTP message is truncated prematurely", EXPFILL }} + + }; + + expert_module_t *expert_dtp; + + proto_dtp = proto_register_protocol("Dynamic Trunk Protocol", "DTP", "dtp"); + proto_register_field_array(proto_dtp, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + expert_dtp = expert_register_protocol(proto_dtp); + expert_register_field_array(expert_dtp, ei, array_length(ei)); + + dtp_handle = register_dissector("dtp", dissect_dtp, proto_dtp); +} + +void +proto_reg_handoff_dtp(void) +{ + dissector_add_uint("llc.cisco_pid", CISCO_PID_DTP, dtp_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: + */ |