/* packet-slowprotocols.c

 * Routines for EtherType (0x8809) Slow Protocols disassembly.

 * IEEE Std 802.3, Annex 57A

 *

 * Copyright 2002 Steve Housley <steve_housley@3com.com>

 * Copyright 2005 Dominique Bastien <dbastien@accedian.com>

 * Copyright 2009 Artem Tamazov <artem.tamazov@telllabs.com>

 * Copyright 2010 Roberto Morro <roberto.morro[AT]tilab.com>

 * Copyright 2014 Philip Rosenberg-Watt <p.rosenberg-watt[at]cablelabs.com.>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

 * SPDX-License-Identifier: GPL-2.0-or-later

 */

#include "config.h"

#include <epan/packet.h>

#include <epan/etypes.h>

#include "packet-slowprotocols.h"

/* General declarations */

void proto_register_slow_protocols(void);

void proto_reg_handoff_slow_protocols(void);

static dissector_handle_t slow_protocols_handle;

static dissector_table_t slow_protocols_dissector_table;

static const value_string subtype_vals[] = {

    { LACP_SUBTYPE   , "LACP" },

    { MARKER_SUBTYPE , "Marker Protocol" },

    { OAM_SUBTYPE    , "OAM" },

    { OSSP_SUBTYPE   , "Organization Specific Slow Protocol" },

    { 0, NULL }

};

/* Initialise the protocol and registered fields */

static int proto_slow;

static int hf_slow_subtype;

/* Initialise the subtree pointers */

static int ett_slow;

/*

 * Name: dissect_slow_protocols

 *

 * Description:

 *    This function is used to dissect the slow protocols defined in IEEE802.3

 *    CSMA/CD. The current slow protocols subtypes are define in Annex 57A of

 *    the 802.3 document. In case of an unsupported slow protocol, we only

 *    fill the protocol and info columns.

 *

 * Input Arguments:

 *    tvb:   buffer associated with the rcv packet (see tvbuff.h).

 *    pinfo: structure associated with the rcv packet (see packet_info.h).

 *    tree:  the protocol tree associated with the rcv packet (see proto.h).

 *

 * Return Values:

 *    None

 */

static int

dissect_slow_protocols(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)

{

    uint8_t     subtype;

    proto_tree *pdu_tree;

    proto_item *pdu_item;

    tvbuff_t   *next_tvb;

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "Slow Protocols");

    subtype = tvb_get_uint8(tvb, 0);

    col_add_fstr(pinfo->cinfo, COL_INFO, "Subtype = %u", subtype);

    if (tree)

    {

        pdu_item = proto_tree_add_item(tree, proto_slow, tvb, 0, 1, ENC_NA);

        pdu_tree = proto_item_add_subtree(pdu_item, ett_slow);

        /* Subtype */

        proto_tree_add_item(pdu_tree, hf_slow_subtype, tvb, 0, 1, ENC_BIG_ENDIAN);

    }

    next_tvb = tvb_new_subset_remaining(tvb, 1);

    if (!dissector_try_uint_with_data(slow_protocols_dissector_table, subtype,

                                next_tvb, pinfo, tree, true, NULL))

        call_data_dissector(next_tvb, pinfo, tree);

    set_actual_length(tvb, tvb_captured_length(next_tvb) + 1);

    return tvb_captured_length(tvb);

}

/* Register the protocol with Wireshark */

void

proto_register_slow_protocols(void)

{

/* Setup list of header fields */

    static hf_register_info hf[] = {

        { &hf_slow_subtype,

          { "Slow Protocols subtype",    "slow.subtype",

            FT_UINT8,    BASE_HEX,    VALS(subtype_vals),    0x0,

            NULL, HFILL }},

    };

    /* Setup protocol subtree array */

    static int *ett[] = {

        &ett_slow,

    };

    /* Register the protocol name and description */

    proto_slow = proto_register_protocol("802.3 Slow protocols", "Slow Protocols", "slow");

    /* Required function calls to register the header fields and subtrees used */

    proto_register_field_array(proto_slow, hf, array_length(hf));

    proto_register_subtree_array(ett, array_length(ett));

    /* Register the dissector handle */

    slow_protocols_handle = register_dissector("slow", dissect_slow_protocols, proto_slow);

    /* subdissector code */

    slow_protocols_dissector_table = register_dissector_table("slow.subtype",

                                                              "Slow protocol subtype",

                                                               proto_slow, FT_UINT8, BASE_DEC);

}

void

proto_reg_handoff_slow_protocols(void)

{

    dissector_add_uint("ethertype", ETHERTYPE_SLOW_PROTOCOLS, slow_protocols_handle);

}

/*

 * 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:

 */