/* packet-btmesh-beacon.c

 * Routines for Bluetooth mesh PB-ADV dissection

 *

 * Copyright 2019, Piotr Winiarczyk <wino45@gmail.com>

 *

 * Wireshark - Network traffic analyzer

 * By Gerald Combs <gerald@wireshark.org>

 * Copyright 1998 Gerald Combs

 *

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

 *

 * Ref: Mesh Profile v1.0

 * https://www.bluetooth.com/specifications/mesh-specifications

 */

#include "config.h"

#include <epan/packet.h>

#include <epan/prefs.h>

#include <epan/expert.h>

#include <epan/tfs.h>

#include "packet-btmesh.h"

#define BEACON_UNPROVISION 0x00

#define BEACON_SECURE      0x01

void proto_register_btmesh_beacon(void);

static int proto_btmesh_beacon;

static int hf_btmesh_beacon_type;

static int hf_btmesh_beacon_uuid;

static int hf_btmesh_beacon_oob;

static int hf_btmesh_beacon_oob_other;

static int hf_btmesh_beacon_oob_electronic;

static int hf_btmesh_beacon_oob_2d_code;

static int hf_btmesh_beacon_oob_bar_code;

static int hf_btmesh_beacon_oob_nfc;

static int hf_btmesh_beacon_oob_number;

static int hf_btmesh_beacon_oob_string;

static int hf_btmesh_beacon_oob_rfu;

static int hf_btmesh_beacon_oob_on_box;

static int hf_btmesh_beacon_oob_inside_box;

static int hf_btmesh_beacon_oob_on_paper;

static int hf_btmesh_beacon_oob_inside_manual;

static int hf_btmesh_beacon_oob_on_device;

static int hf_btmesh_beacon_uri_hash;

static int hf_btmesh_beacon_flags;

static int hf_btmesh_beacon_flags_key_refresh;

static int hf_btmesh_beacon_flags_iv_update;

static int hf_btmesh_beacon_flags_rfu;

static int hf_btmesh_beacon_network_id;

static int hf_btmesh_beacon_ivindex;

//TODO: check authentication value

static int hf_btmesh_beacon_authentication_value;

static int hf_btmesh_beacon_unknown_data;

static int ett_btmesh_beacon;

static int ett_btmesh_beacon_oob;

static int ett_btmesh_beacon_flags;

static expert_field ei_btmesh_beacon_unknown_beacon_type;

static expert_field ei_btmesh_beacon_unknown_payload;

static expert_field ei_btmesh_beacon_rfu_not_zero;

static const value_string btmesh_beacon_type[] = {

    { 0, "Unprovisioned Device Beacon" },

    { 1, "Secure Network Beacon" },

    { 0, NULL }

};

static const true_false_string flags_key_refresh = {

  "Key Refresh in progress",

  "Key Refresh not in progress"

};

static const true_false_string flags_iv_update = {

  "IV Update active",

  "Normal operation"

};

static int

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

{

    proto_item *item, *oob_item, *flags_item;

    proto_tree *sub_tree, *oob_tree, *flags_tree;

    unsigned offset = 0;

    unsigned data_size = 0;

    btle_mesh_transport_ctx_t *tr_ctx;

    btle_mesh_transport_ctx_t dummy_ctx = {E_BTMESH_TR_UNKNOWN, false, 0};

    uint16_t rfu_bits16;

    uint8_t rfu_bits8;

    col_set_str(pinfo->cinfo, COL_PROTOCOL, "BT Mesh Beacon");

    if (data == NULL) {

        tr_ctx = &dummy_ctx;

    } else {

        tr_ctx = (btle_mesh_transport_ctx_t *) data;

    }

    item = proto_tree_add_item(tree, proto_btmesh_beacon, tvb, offset, -1, ENC_NA);

    sub_tree = proto_item_add_subtree(item, ett_btmesh_beacon);

    uint8_t beacon_type = tvb_get_uint8(tvb, offset);

    proto_tree_add_item(sub_tree, hf_btmesh_beacon_type, tvb, offset, 1, ENC_NA);

    offset += 1;

    col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(beacon_type, btmesh_beacon_type, "Unknown Beacon Type"));

    if (tr_ctx->fragmented) {

        switch (tr_ctx->transport) {

            case E_BTMESH_TR_PROXY:

                col_append_str(pinfo->cinfo, COL_INFO," (Last Segment)");

            break;

            default:

            //No default is needed since this is an additional information only

            break;

        }

    }

    switch(beacon_type) {

        case BEACON_UNPROVISION:

            proto_tree_add_item(sub_tree, hf_btmesh_beacon_uuid, tvb, offset, 16, ENC_BIG_ENDIAN);

            offset += 16;

            oob_item = proto_tree_add_item(sub_tree, hf_btmesh_beacon_oob, tvb, offset, 2, ENC_BIG_ENDIAN);

            oob_tree = proto_item_add_subtree(oob_item, ett_btmesh_beacon_oob);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_other, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_electronic, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_2d_code, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_bar_code, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_nfc, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_number, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_string, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_rfu, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_on_box, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_inside_box, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_on_paper, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_inside_manual, tvb, offset, 2, ENC_BIG_ENDIAN);

            proto_tree_add_item(oob_tree, hf_btmesh_beacon_oob_on_device, tvb, offset, 2, ENC_BIG_ENDIAN);

            rfu_bits16 = (tvb_get_uint16(tvb, offset, ENC_BIG_ENDIAN) & 0x0780) >> 7;

            if (rfu_bits16 != 0) {

                //RFU bits should be 0

                proto_tree_add_expert(oob_tree, pinfo, &ei_btmesh_beacon_rfu_not_zero, tvb, offset, -1);

            }

            offset += 2;

            data_size = tvb_reported_length(tvb);

            if (data_size == offset + 4 ) {

                proto_tree_add_item(sub_tree, hf_btmesh_beacon_uri_hash, tvb, offset, 4, ENC_NA);

                offset += 4;

            }

            //Wrong size handled outside switch/case

        break;

        case BEACON_SECURE:

            flags_item = proto_tree_add_item(sub_tree, hf_btmesh_beacon_flags, tvb, offset, 1, ENC_NA);

            flags_tree = proto_item_add_subtree(flags_item, ett_btmesh_beacon_flags);

            proto_tree_add_item(flags_tree, hf_btmesh_beacon_flags_key_refresh, tvb, offset, 1, ENC_NA);

            proto_tree_add_item(flags_tree, hf_btmesh_beacon_flags_iv_update, tvb, offset, 1, ENC_NA);

            proto_tree_add_item(flags_tree, hf_btmesh_beacon_flags_rfu, tvb, offset, 1, ENC_NA);

            rfu_bits8 = tvb_get_uint8(tvb, offset) >> 2;

            if (rfu_bits8 != 0) {

                //RFU bits should be 0

                proto_tree_add_expert(flags_tree, pinfo, &ei_btmesh_beacon_rfu_not_zero, tvb, offset, -1);

            }

            offset += 1;

            proto_tree_add_item(sub_tree, hf_btmesh_beacon_network_id, tvb, offset, 8, ENC_NA);

            offset += 8;

            proto_tree_add_item(sub_tree, hf_btmesh_beacon_ivindex, tvb, offset, 4, ENC_BIG_ENDIAN);

            offset += 4;

            proto_tree_add_item(sub_tree, hf_btmesh_beacon_authentication_value, tvb, offset, 8, ENC_NA);

            offset += 8;

        break;

        default:

            //Unknown mesh beacon type, display data and flag it

            proto_tree_add_item(sub_tree, hf_btmesh_beacon_unknown_data, tvb, offset, -1, ENC_NA);

            proto_tree_add_expert(sub_tree, pinfo, &ei_btmesh_beacon_unknown_beacon_type, tvb, offset, -1);

            offset += tvb_captured_length_remaining(tvb, offset);

        break;

    }

    //There is still some data but all data should be already disssected

    if (tvb_captured_length_remaining(tvb, offset) != 0) {

        proto_tree_add_expert(sub_tree, pinfo, &ei_btmesh_beacon_unknown_payload, tvb, offset, -1);

    }

    return tvb_reported_length(tvb);

}

void

proto_register_btmesh_beacon(void)

{

    static hf_register_info hf[] = {

        { &hf_btmesh_beacon_type,

            { "Type", "beacon.type",

                FT_UINT8, BASE_DEC, VALS(btmesh_beacon_type), 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_uuid,

            { "Device UUID", "beacon.uuid",

                FT_GUID, BASE_NONE, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_oob,

            { "OOB Information", "beacon.oob",

                FT_UINT16, BASE_HEX, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_oob_other,

            { "Other", "beacon.oob.other",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0001,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_electronic,

            { "Electronic / URI", "beacon.oob.electronic",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0002,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_2d_code,

            { "2D machine-readable code", "beacon.oob.2d_code",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0004,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_bar_code,

            { "Bar code", "beacon.oob.bar_code",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0008,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_nfc,

            { "Near Field Communication (NFC)", "beacon.oob.nfc",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0010,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_number,

            { "Number", "beacon.oob.number",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0020,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_string,

            { "String", "beacon.oob.string",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0040,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_rfu,

            { "Reserved for Future Use", "beacon.oob.rfu",

                FT_UINT16, BASE_DEC, NULL, 0x0780,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_on_box,

            { "On box", "beacon.oob.on_box",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x0800,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_inside_box,

            { "Inside box", "beacon.oob.inside_box",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x1000,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_on_paper,

            { "On piece of paper", "beacon.oob.on_paper",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x2000,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_inside_manual,

            { "Inside manual", "beacon.oob.inside_manual",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x4000,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_oob_on_device,

            { "On device", "beacon.oob.on_device",

                FT_BOOLEAN, 16, TFS(&tfs_available_not_available), 0x8000,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_uri_hash,

            { "URI Hash", "beacon.uri_hash",

                FT_BYTES, BASE_NONE, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_flags,

            { "Flags", "beacon.flags",

                FT_UINT8, BASE_HEX, NULL, 0x0,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_flags_key_refresh,

            { "Key Refresh Flag", "beacon.flags.key_refresh",

                FT_BOOLEAN, 8, TFS(&flags_key_refresh), 0x01,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_flags_iv_update,

            { "IV Update Flag", "beacon.flags.iv_update",

                FT_BOOLEAN, 8, TFS(&flags_iv_update), 0x02,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_flags_rfu,

            { "Reserved for Future Use", "beacon.flags.rfu",

                FT_UINT8, BASE_DEC, NULL, 0xFC,

                NULL, HFILL }

        },

       { &hf_btmesh_beacon_network_id,

            { "Network ID", "beacon.network_id",

                FT_BYTES, BASE_NONE, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_ivindex,

            { "IV Index", "beacon.ivindex",

                FT_UINT32, BASE_DEC, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_authentication_value,

            { "Authentication Value", "beacon.authentication_value",

                FT_BYTES, BASE_NONE, NULL, 0x0,

                NULL, HFILL }

        },

        { &hf_btmesh_beacon_unknown_data,

            { "Unknown Data", "beacon.unknown_data",

                FT_BYTES, BASE_NONE, NULL, 0x0,

                NULL, HFILL }

        },

    };

    static int *ett[] = {

        &ett_btmesh_beacon,

        &ett_btmesh_beacon_oob,

        &ett_btmesh_beacon_flags,

    };

    static ei_register_info ei[] = {

        { &ei_btmesh_beacon_unknown_beacon_type,{ "beacon.unknown_beacon_type", PI_PROTOCOL, PI_ERROR, "Unknown Beacon Type", EXPFILL } },

        { &ei_btmesh_beacon_unknown_payload,{ "beacon.unknown_payload", PI_PROTOCOL, PI_ERROR, "Unknown Payload", EXPFILL } },

        { &ei_btmesh_beacon_rfu_not_zero,{ "beacon.rfu_not_zero", PI_PROTOCOL, PI_WARN, "Reserved for Future Use value not equal to 0", EXPFILL } },

    };

    expert_module_t* expert_btmesh_beacon;

    proto_btmesh_beacon = proto_register_protocol("Bluetooth Mesh Beacon", "BT Mesh beacon", "beacon");

    proto_register_field_array(proto_btmesh_beacon, hf, array_length(hf));

    proto_register_subtree_array(ett, array_length(ett));

    expert_btmesh_beacon = expert_register_protocol(proto_btmesh_beacon);

    expert_register_field_array(expert_btmesh_beacon, ei, array_length(ei));

    prefs_register_protocol_subtree("Bluetooth", proto_btmesh_beacon, NULL);

    register_dissector("btmesh.beacon", dissect_btmesh_beacon_msg, proto_btmesh_beacon);

}

/*

 * Editor modelines

 *

 * Local Variables:

 * c-basic-offset: 4

 * tab-width: 8

 * indent-tabs-mode: nil

 * End:

 *

 * ex: set shiftwidth=4 tabstop=8 expandtab:

 * :indentSize=4:tabSize=8:noTabs=true:

 */