/* packet-dpauxmon.c

 * Routines for DisplayPort AUX-Channel monitor dissection

 * Copyright 2018, Dirk Eibach, Guntermann & Drunck GmbH <dirk.eibach@gdsys.cc>

 *

 * 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/conversation.h>

#include <epan/proto_data.h>

#include <wiretap/wtap.h>

#include "packet-dpaux.h"

enum {

    DPAUXMON_DATA = 0x00,

    DPAUXMON_DATA_END = 0x01,

    DPAUXMON_EVENT = 0x02,

    DPAUXMON_START = 0x03,

    DPAUXMON_STOP = 0x04,

    DPAUXMON_TS_OVERFLOW = 0x84,

};

void proto_reg_handoff_dpauxmon(void);

void proto_register_dpauxmon(void);

static dissector_handle_t dpaux_handle;

static dissector_handle_t dpauxmon_handle;

/* Initialize the protocol and registered fields */

static int proto_dpauxmon;

static int hf_packet_type;

static int hf_origin;

static int hf_inputs;

static int hf_hpd;

static int hf_in0;

static int hf_in1;

static int hf_in2;

static int * const input_fields[] = {

    &hf_hpd,

    &hf_in0,

    &hf_in1,

    &hf_in2,

    NULL

};

/* Initialize the subtree pointers */

static int ett_dpauxmon;

static const value_string packet_type_vals[] = {

    { DPAUXMON_DATA, "Data" },

    { DPAUXMON_EVENT, "Event" },

    { DPAUXMON_START, "Start" },

    { DPAUXMON_STOP, "Stop" },

    { DPAUXMON_TS_OVERFLOW, "Timestamp Overflow" },

    { 0, NULL }

};

static const value_string origin_vals[] = {

    { 0, "Sink" },

    { 1, "Source" },

    { 0, NULL }

};

static int

dissect_dpauxmon(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,

        void *data _U_)

{

    proto_item *ti;

    proto_tree *dpauxmon_tree;

    uint32_t packet_type;

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "DPAUXMON");

    col_set_str(pinfo->cinfo, COL_RES_DL_DST, "N/A");

    col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "Internal");

    /* create display subtree for the protocol */

    ti = proto_tree_add_item(tree, proto_dpauxmon, tvb, 0, -1, ENC_NA);

    dpauxmon_tree = proto_item_add_subtree(ti, ett_dpauxmon);

    proto_tree_add_item_ret_uint(dpauxmon_tree, hf_packet_type, tvb, 0, 1, ENC_NA, &packet_type);

    col_add_fstr(pinfo->cinfo, COL_INFO, "DisplayPort AUX channel - %s", val_to_str_const(packet_type, packet_type_vals, "Unknown"));

    switch (packet_type) {

    case DPAUXMON_DATA: {

        struct dpaux_info dpaux_info;

        dpaux_info.from_source = tvb_get_uint8(tvb, 1);

        proto_tree_add_uint(dpauxmon_tree, hf_origin, tvb, 1, 1, dpaux_info.from_source);

        call_dissector_with_data(dpaux_handle, tvb_new_subset_remaining(tvb, 2),

                 pinfo, dpauxmon_tree, &dpaux_info);

        break;

        }

    case DPAUXMON_EVENT:

    case DPAUXMON_START:

        proto_tree_add_bitmask(dpauxmon_tree, tvb, 1, hf_inputs, 0, input_fields,

                               ENC_BIG_ENDIAN);

        break;

    case DPAUXMON_STOP:

        break;

    case DPAUXMON_TS_OVERFLOW:

        break;

    };

    return tvb_captured_length(tvb);

}

void

proto_register_dpauxmon(void)

{

    /* Setup protocol subtree array */

    static int *ett[] = {

        &ett_dpauxmon

    };

    /* Setup list of header fields  See Section 1.5 of README.dissector for

     * details. */

    static hf_register_info hf[] = {

        { &hf_packet_type,

          { "Packet Type", "dpauxmon.packet_type",

            FT_UINT8, BASE_DEC, VALS(packet_type_vals), 0,

            NULL, HFILL }

        },

        { &hf_origin,

          { "Origin", "dpauxmon.origin",

            FT_UINT8, BASE_DEC, VALS(origin_vals), 0,

            NULL, HFILL }

        },

        { &hf_inputs,

          { "Inputs", "dpauxmon.inputs",

            FT_UINT8, BASE_HEX, NULL, 0,

            NULL, HFILL }

        },

        { &hf_hpd,

          { "Hotplug Detect", "dpauxmon.hpd",

            FT_BOOLEAN, 4, NULL, 0x1,

            NULL, HFILL }

        },

        { &hf_in0,

          { "IN0", "dpauxmon.in0",

            FT_BOOLEAN, 4, NULL, 0x2,

            NULL, HFILL }

        },

        { &hf_in1,

          { "IN1", "dpauxmon.in1",

            FT_BOOLEAN, 4, NULL, 0x4,

            NULL, HFILL }

        },

        { &hf_in2,

          { "IN2", "dpauxmon.in2",

            FT_BOOLEAN, 4, NULL, 0x8,

            NULL, HFILL }

        },

    };

    /* Register the protocol name and description */

    proto_dpauxmon = proto_register_protocol("DPAUXMON DisplayPort AUX channel monitor", "DPAUXMON", "dpauxmon");

    proto_register_field_array(proto_dpauxmon, hf, array_length(hf));

    proto_register_subtree_array(ett, array_length(ett));

    dpauxmon_handle = register_dissector("dpauxmon", dissect_dpauxmon, proto_dpauxmon);

}

void

proto_reg_handoff_dpauxmon(void)

{

    static bool initialized = false;

    dpaux_handle = find_dissector_add_dependency("dpaux", proto_dpauxmon);

    if (!initialized) {

        initialized = true;

    } else {

        dissector_delete_uint("wtap_encap", WTAP_ENCAP_DPAUXMON, dpauxmon_handle);

    }

    dissector_add_uint("wtap_encap", WTAP_ENCAP_DPAUXMON, dpauxmon_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:

 */