/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2018 Lubomir Rintel <lkundrak@v3.sk>
 */

#include "src/core/nm-default-daemon.h"

#include "nm-manager.h"
#include "nm-device-wpan.h"

#include <stdlib.h>
#include <sys/types.h>
#include <linux/if.h>

#include "nm-act-request.h"
#include "nm-device-private.h"
#include "nm-ip4-config.h"
#include "libnm-platform/nm-platform.h"
#include "nm-device-factory.h"
#include "nm-setting-wpan.h"
#include "libnm-core-intern/nm-core-internal.h"

#define _NMLOG_DEVICE_TYPE NMDeviceWpan
#include "nm-device-logging.h"

/*****************************************************************************/

struct _NMDeviceWpan {
    NMDevice parent;
};

struct _NMDeviceWpanClass {
    NMDeviceClass parent;
};

G_DEFINE_TYPE(NMDeviceWpan, nm_device_wpan, NM_TYPE_DEVICE)

/*****************************************************************************/

static gboolean
complete_connection(NMDevice *           device,
                    NMConnection *       connection,
                    const char *         specific_object,
                    NMConnection *const *existing_connections,
                    GError **            error)
{
    NMSettingWpan *s_wpan;

    nm_utils_complete_generic(nm_device_get_platform(device),
                              connection,
                              NM_SETTING_WPAN_SETTING_NAME,
                              existing_connections,
                              NULL,
                              _("WPAN connection"),
                              NULL,
                              NULL,
                              TRUE);

    s_wpan = NM_SETTING_WPAN(nm_connection_get_setting(connection, NM_TYPE_SETTING_WPAN));
    if (!s_wpan) {
        g_set_error_literal(error,
                            NM_DEVICE_ERROR,
                            NM_DEVICE_ERROR_INVALID_CONNECTION,
                            "A 'wpan' setting is required.");
        return FALSE;
    }

    return TRUE;
}

static void
update_connection(NMDevice *device, NMConnection *connection)
{
    NMSettingWpan *s_wpan =
        NM_SETTING_WPAN(nm_connection_get_setting(connection, NM_TYPE_SETTING_WPAN));

    if (!s_wpan) {
        s_wpan = (NMSettingWpan *) nm_setting_wpan_new();
        nm_connection_add_setting(connection, (NMSetting *) s_wpan);
    }
}

static gboolean
check_connection_compatible(NMDevice *device, NMConnection *connection, GError **error)
{
    NMSettingWpan *s_wpan;
    const char *   mac, *hw_addr;

    if (!NM_DEVICE_CLASS(nm_device_wpan_parent_class)
             ->check_connection_compatible(device, connection, error))
        return FALSE;

    s_wpan = NM_SETTING_WPAN(nm_connection_get_setting(connection, NM_TYPE_SETTING_WPAN));

    mac = nm_setting_wpan_get_mac_address(s_wpan);
    if (mac) {
        hw_addr = nm_device_get_hw_address(device);
        if (!nm_utils_hwaddr_matches(mac, -1, hw_addr, -1)) {
            nm_utils_error_set_literal(error,
                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,
                                       "MAC address mismatches");
            return FALSE;
        }
    }

    return TRUE;
}

static NMActStageReturn
act_stage1_prepare(NMDevice *device, NMDeviceStateReason *out_failure_reason)
{
    NMDeviceWpan *        self = NM_DEVICE_WPAN(device);
    NMSettingWpan *       s_wpan;
    NMPlatform *          platform;
    guint16               pan_id;
    guint16               short_address;
    gint16                page, channel;
    int                   ifindex;
    const guint8 *        hwaddr;
    gsize                 hwaddr_len = 0;
    const NMPlatformLink *lowpan_plink;
    NMDevice *            lowpan_device = NULL;
    NMActStageReturn      ret           = NM_ACT_STAGE_RETURN_FAILURE;

    platform = nm_device_get_platform(device);
    nm_assert(NM_IS_PLATFORM(platform));

    ifindex = nm_device_get_ifindex(device);

    g_return_val_if_fail(ifindex > 0, NM_ACT_STAGE_RETURN_FAILURE);

    s_wpan = nm_device_get_applied_setting(device, NM_TYPE_SETTING_WPAN);

    g_return_val_if_fail(s_wpan, NM_ACT_STAGE_RETURN_FAILURE);

    hwaddr = nm_platform_link_get_address(platform, ifindex, &hwaddr_len);

    if (!hwaddr) {
        *out_failure_reason = NM_DEVICE_STATE_REASON_CONFIG_FAILED;
        return NM_ACT_STAGE_RETURN_FAILURE;
    }

    /* As of kernel 4.16, the 6LoWPAN devices layered on top of WPANs
     * need to be DOWN as well as the WPAN device itself in order to
     * modify the WPAN properties. */
    lowpan_plink =
        nm_platform_link_get_by_address(platform, NM_LINK_TYPE_6LOWPAN, hwaddr, hwaddr_len);
    if (lowpan_plink && NM_FLAGS_HAS(lowpan_plink->n_ifi_flags, IFF_UP)) {
        lowpan_device = nm_manager_get_device_by_ifindex(NM_MANAGER_GET, lowpan_plink->ifindex);
    }

    if (lowpan_device)
        nm_device_take_down(lowpan_device, TRUE);

    nm_device_take_down(device, TRUE);

    pan_id = nm_setting_wpan_get_pan_id(s_wpan);
    if (pan_id != G_MAXUINT16) {
        if (!nm_platform_wpan_set_pan_id(platform, ifindex, pan_id)) {
            _LOGW(LOGD_DEVICE, "unable to set the PAN ID");
            goto out;
        }
    }

    short_address = nm_setting_wpan_get_short_address(s_wpan);
    if (short_address != G_MAXUINT16) {
        if (!nm_platform_wpan_set_short_addr(platform, ifindex, short_address)) {
            _LOGW(LOGD_DEVICE, "unable to set the short address");
            goto out;
        }
    }

    channel = nm_setting_wpan_get_channel(s_wpan);
    if (channel != NM_SETTING_WPAN_CHANNEL_DEFAULT) {
        page = nm_setting_wpan_get_page(s_wpan);
        if (!nm_platform_wpan_set_channel(platform, ifindex, page, channel)) {
            _LOGW(LOGD_DEVICE, "unable to set the channel");
            goto out;
        }
    }

    ret = NM_ACT_STAGE_RETURN_SUCCESS;

out:
    nm_device_bring_up(device, TRUE, NULL);

    if (lowpan_device)
        nm_device_bring_up(lowpan_device, TRUE, NULL);

    return ret;
}

/*****************************************************************************/

static void
nm_device_wpan_init(NMDeviceWpan *self)
{}

static const NMDBusInterfaceInfoExtended interface_info_device_wpan = {
    .parent = NM_DEFINE_GDBUS_INTERFACE_INFO_INIT(
        NM_DBUS_INTERFACE_DEVICE_WPAN,
        .properties = NM_DEFINE_GDBUS_PROPERTY_INFOS(
            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE("HwAddress",
                                                           "s",
                                                           NM_DEVICE_HW_ADDRESS), ), ),
};

static void
nm_device_wpan_class_init(NMDeviceWpanClass *klass)
{
    NMDeviceClass *    device_class      = NM_DEVICE_CLASS(klass);
    NMDBusObjectClass *dbus_object_class = NM_DBUS_OBJECT_CLASS(klass);

    dbus_object_class->interface_infos = NM_DBUS_INTERFACE_INFOS(&interface_info_device_wpan);

    device_class->connection_type_supported        = NM_SETTING_WPAN_SETTING_NAME;
    device_class->connection_type_check_compatible = NM_SETTING_WPAN_SETTING_NAME;
    device_class->link_types                       = NM_DEVICE_DEFINE_LINK_TYPES(NM_LINK_TYPE_WPAN);

    device_class->complete_connection         = complete_connection;
    device_class->check_connection_compatible = check_connection_compatible;
    device_class->update_connection           = update_connection;
    device_class->act_stage1_prepare          = act_stage1_prepare;
}

/*****************************************************************************/

#define NM_TYPE_WPAN_DEVICE_FACTORY (nm_wpan_device_factory_get_type())
#define NM_WPAN_DEVICE_FACTORY(obj) \
    (G_TYPE_CHECK_INSTANCE_CAST((obj), NM_TYPE_WPAN_DEVICE_FACTORY, NMWpanDeviceFactory))

static NMDevice *
create_device(NMDeviceFactory *     factory,
              const char *          iface,
              const NMPlatformLink *plink,
              NMConnection *        connection,
              gboolean *            out_ignore)
{
    return g_object_new(NM_TYPE_DEVICE_WPAN,
                        NM_DEVICE_IFACE,
                        iface,
                        NM_DEVICE_TYPE_DESC,
                        "WPAN",
                        NM_DEVICE_DEVICE_TYPE,
                        NM_DEVICE_TYPE_WPAN,
                        NM_DEVICE_LINK_TYPE,
                        NM_LINK_TYPE_WPAN,
                        NULL);
}

NM_DEVICE_FACTORY_DEFINE_INTERNAL(
    WPAN,
    Wpan,
    wpan,
    NM_DEVICE_FACTORY_DECLARE_LINK_TYPES(NM_LINK_TYPE_WPAN)
        NM_DEVICE_FACTORY_DECLARE_SETTING_TYPES(NM_SETTING_WPAN_SETTING_NAME),
    factory_class->create_device = create_device;);