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

/*

 * Copyright (C) 2013 - 2015 Red Hat, Inc.

 */

#include "nm-default.h"

#include "nm-device-tun.h"

#include <stdlib.h>

#include <sys/types.h>

#include <linux/if_tun.h>

#include "nm-act-request.h"

#include "nm-device-private.h"

#include "nm-ip4-config.h"

#include "platform/nm-platform.h"

#include "nm-device-factory.h"

#include "nm-setting-tun.h"

#include "nm-core-internal.h"

#define _NMLOG_DEVICE_TYPE NMDeviceTun

#include "nm-device-logging.h"

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

NM_GOBJECT_PROPERTIES_DEFINE(NMDeviceTun,

                             PROP_OWNER,

                             PROP_GROUP,

                             PROP_MODE,

                             PROP_NO_PI,

                             PROP_VNET_HDR,

                             PROP_MULTI_QUEUE, );

typedef struct {

    NMPlatformLnkTun props;

} NMDeviceTunPrivate;

struct _NMDeviceTun {

    NMDevice           parent;

    NMDeviceTunPrivate _priv;

};

struct _NMDeviceTunClass {

    NMDeviceClass parent;

};

G_DEFINE_TYPE(NMDeviceTun, nm_device_tun, NM_TYPE_DEVICE)

#define NM_DEVICE_TUN_GET_PRIVATE(self) \

    _NM_GET_PRIVATE(self, NMDeviceTun, NM_IS_DEVICE_TUN, NMDevice)

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

static void

update_properties_from_struct(NMDeviceTun *self, const NMPlatformLnkTun *props)

{

    NMDeviceTunPrivate *   priv   = NM_DEVICE_TUN_GET_PRIVATE(self);

    const NMPlatformLnkTun props0 = {};

    if (!props) {

        /* allow passing %NULL to reset all properties. */

        props = &props;;

    }

    g_object_freeze_notify(G_OBJECT(self));

#define CHECK_PROPERTY_CHANGED_VALID(field, prop)                   \

    G_STMT_START                                                    \

    {                                                               \

        if (priv->props.field != props->field                       \

            || priv->props.field##_valid != props->field##_valid) { \

            priv->props.field##_valid = props->field##_valid;       \

            priv->props.field         = props->field;               \

            _notify(self, prop);                                    \

        }                                                           \

    }                                                               \

    G_STMT_END

#define CHECK_PROPERTY_CHANGED(field, prop)      \

    G_STMT_START                                 \

    {                                            \

        if (priv->props.field != props->field) { \

            priv->props.field = props->field;    \

            _notify(self, prop);                 \

        }                                        \

    }                                            \

    G_STMT_END

    CHECK_PROPERTY_CHANGED_VALID(owner, PROP_OWNER);

    CHECK_PROPERTY_CHANGED_VALID(group, PROP_GROUP);

    CHECK_PROPERTY_CHANGED(type, PROP_MODE);

    CHECK_PROPERTY_CHANGED(pi, PROP_NO_PI);

    CHECK_PROPERTY_CHANGED(vnet_hdr, PROP_VNET_HDR);

    CHECK_PROPERTY_CHANGED(multi_queue, PROP_MULTI_QUEUE);

    g_object_thaw_notify(G_OBJECT(self));

}

static void

update_properties(NMDeviceTun *self)

{

    NMPlatformLnkTun        props_storage;

    const NMPlatformLnkTun *props = NULL;

    int                     ifindex;

    ifindex = nm_device_get_ifindex(NM_DEVICE(self));

    if (ifindex > 0

        && nm_platform_link_tun_get_properties(nm_device_get_platform(NM_DEVICE(self)),

                                               ifindex,

                                               &props_storage))

        props = &props_storage;

    update_properties_from_struct(self, props);

}

static NMDeviceCapabilities

get_generic_capabilities(NMDevice *dev)

{

    return NM_DEVICE_CAP_IS_SOFTWARE;

}

static void

link_changed(NMDevice *device, const NMPlatformLink *pllink)

{

    NM_DEVICE_CLASS(nm_device_tun_parent_class)->link_changed(device, pllink);

    update_properties(NM_DEVICE_TUN(device));

}

static gboolean

complete_connection(NMDevice *           device,

                    NMConnection *       connection,

                    const char *         specific_object,

                    NMConnection *const *existing_connections,

                    GError **            error)

{

    NMSettingTun *s_tun;

    nm_utils_complete_generic(nm_device_get_platform(device),

                              connection,

                              NM_SETTING_TUN_SETTING_NAME,

                              existing_connections,

                              NULL,

                              _("TUN connection"),

                              NULL,

                              NULL,

                              TRUE);

    s_tun = nm_connection_get_setting_tun(connection);

    if (!s_tun) {

        g_set_error_literal(error,

                            NM_DEVICE_ERROR,

                            NM_DEVICE_ERROR_INVALID_CONNECTION,

                            "A 'tun' setting is required.");

        return FALSE;

    }

    return TRUE;

}

static void

update_connection(NMDevice *device, NMConnection *connection)

{

    NMDeviceTun *       self = NM_DEVICE_TUN(device);

    NMDeviceTunPrivate *priv = NM_DEVICE_TUN_GET_PRIVATE(self);

    NMSettingTun *      s_tun;

    NMSettingTunMode    mode;

    char                s_buf[100];

    const char *        str;

    /* Note: since we read tun properties from sysctl for older kernels,

     *       we don't get proper change notifications. Make sure that all our

     *       tun properties are up to date at this point. We should not do this,

     *       if we would entirely rely on netlink events. */

    update_properties(NM_DEVICE_TUN(device));

    switch (priv->props.type) {

    case IFF_TUN:

        mode = NM_SETTING_TUN_MODE_TUN;

        break;

    case IFF_TAP:

        mode = NM_SETTING_TUN_MODE_TAP;

        break;

    default:

        /* Huh? */

        return;

    }

    s_tun = nm_connection_get_setting_tun(connection);

    if (!s_tun) {

        s_tun = (NMSettingTun *) nm_setting_tun_new();

        nm_connection_add_setting(connection, (NMSetting *) s_tun);

    }

    if (mode != nm_setting_tun_get_mode(s_tun))

        g_object_set(G_OBJECT(s_tun), NM_SETTING_TUN_MODE, (guint) mode, NULL);

    str = priv->props.owner_valid ? nm_sprintf_buf(s_buf, "%" G_GINT32_FORMAT, priv->props.owner)

                                  : NULL;

    if (!nm_streq0(str, nm_setting_tun_get_owner(s_tun)))

        g_object_set(G_OBJECT(s_tun), NM_SETTING_TUN_OWNER, str, NULL);

    str = priv->props.group_valid ? nm_sprintf_buf(s_buf, "%" G_GINT32_FORMAT, priv->props.group)

                                  : NULL;

    if (!nm_streq0(str, nm_setting_tun_get_group(s_tun)))

        g_object_set(G_OBJECT(s_tun), NM_SETTING_TUN_GROUP, str, NULL);

    if (priv->props.pi != nm_setting_tun_get_pi(s_tun))

        g_object_set(G_OBJECT(s_tun), NM_SETTING_TUN_PI, (gboolean) priv->props.pi, NULL);

    if (priv->props.vnet_hdr != nm_setting_tun_get_vnet_hdr(s_tun))

        g_object_set(G_OBJECT(s_tun),

                     NM_SETTING_TUN_VNET_HDR,

                     (gboolean) priv->props.vnet_hdr,

                     NULL);

    if (priv->props.multi_queue != nm_setting_tun_get_multi_queue(s_tun))

        g_object_set(G_OBJECT(s_tun),

                     NM_SETTING_TUN_MULTI_QUEUE,

                     (gboolean) priv->props.multi_queue,

                     NULL);

}

static gboolean

create_and_realize(NMDevice *             device,

                   NMConnection *         connection,

                   NMDevice *             parent,

                   const NMPlatformLink **out_plink,

                   GError **              error)

{

    const char *     iface = nm_device_get_iface(device);

    NMPlatformLnkTun props = {};

    NMSettingTun *   s_tun;

    gint64           owner;

    gint64           group;

    int              r;

    s_tun = nm_connection_get_setting_tun(connection);

    g_return_val_if_fail(s_tun, FALSE);

    switch (nm_setting_tun_get_mode(s_tun)) {

    case NM_SETTING_TUN_MODE_TAP:

        props.type = IFF_TAP;

        break;

    case NM_SETTING_TUN_MODE_TUN:

        props.type = IFF_TUN;

        break;

    default:

        g_return_val_if_reached(FALSE);

    }

    owner = _nm_utils_ascii_str_to_int64(nm_setting_tun_get_owner(s_tun), 10, 0, G_MAXINT32, -1);

    if (owner != -1) {

        props.owner_valid = TRUE;

        props.owner       = owner;

    }

    group = _nm_utils_ascii_str_to_int64(nm_setting_tun_get_group(s_tun), 10, 0, G_MAXINT32, -1);

    if (group != -1) {

        props.group_valid = TRUE;

        props.group       = group;

    }

    props.pi          = nm_setting_tun_get_pi(s_tun);

    props.vnet_hdr    = nm_setting_tun_get_vnet_hdr(s_tun);

    props.multi_queue = nm_setting_tun_get_multi_queue(s_tun);

    props.persist     = TRUE;

    r = nm_platform_link_tun_add(nm_device_get_platform(device), iface, &props, out_plink, NULL);

    if (r < 0) {

        g_set_error(error,

                    NM_DEVICE_ERROR,

                    NM_DEVICE_ERROR_CREATION_FAILED,

                    "Failed to create TUN/TAP interface '%s' for '%s': %s",

                    iface,

                    nm_connection_get_id(connection),

                    nm_strerror(r));

        return FALSE;

    }

    return TRUE;

}

static gboolean

_same_og(const char *str, gboolean og_valid, guint32 og_num)

{

    gint64 v;

    v = _nm_utils_ascii_str_to_int64(str, 10, 0, G_MAXINT32, -1);

    return (!og_valid && (v == (gint64) -1)) || (og_valid && (((guint32) v) == og_num));

}

static gboolean

check_connection_compatible(NMDevice *device, NMConnection *connection, GError **error)

{

    NMDeviceTun *       self = NM_DEVICE_TUN(device);

    NMDeviceTunPrivate *priv = NM_DEVICE_TUN_GET_PRIVATE(self);

    NMSettingTunMode    mode;

    NMSettingTun *      s_tun;

    if (!NM_DEVICE_CLASS(nm_device_tun_parent_class)

             ->check_connection_compatible(device, connection, error))

        return FALSE;

    if (nm_device_is_real(device)) {

        switch (priv->props.type) {

        case IFF_TUN:

            mode = NM_SETTING_TUN_MODE_TUN;

            break;

        case IFF_TAP:

            mode = NM_SETTING_TUN_MODE_TAP;

            break;

        default:

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "invalid tun type on device");

            return FALSE;

        }

        s_tun = nm_connection_get_setting_tun(connection);

        if (mode != nm_setting_tun_get_mode(s_tun)) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun mode setting mismatches");

            return FALSE;

        }

        if (!_same_og(nm_setting_tun_get_owner(s_tun),

                      priv->props.owner_valid,

                      priv->props.owner)) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun owner setting mismatches");

            return FALSE;

        }

        if (!_same_og(nm_setting_tun_get_group(s_tun),

                      priv->props.group_valid,

                      priv->props.group)) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun group setting mismatches");

            return FALSE;

        }

        if (nm_setting_tun_get_pi(s_tun) != priv->props.pi) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun pi setting mismatches");

            return FALSE;

        }

        if (nm_setting_tun_get_vnet_hdr(s_tun) != priv->props.vnet_hdr) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun vnet-hdr setting mismatches");

            return FALSE;

        }

        if (nm_setting_tun_get_multi_queue(s_tun) != priv->props.multi_queue) {

            nm_utils_error_set_literal(error,

                                       NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,

                                       "tun multi-queue setting mismatches");

            return FALSE;

        }

    }

    return TRUE;

}

static NMActStageReturn

act_stage1_prepare(NMDevice *device, NMDeviceStateReason *out_failure_reason)

{

    NMDeviceTun *       self = NM_DEVICE_TUN(device);

    NMDeviceTunPrivate *priv = NM_DEVICE_TUN_GET_PRIVATE(self);

    if (priv->props.type == IFF_TUN) {

        /* Nothing to do for TUN devices */

    } else {

        if (!nm_device_hw_addr_set_cloned(device,

                                          nm_device_get_applied_connection(device),

                                          FALSE)) {

            *out_failure_reason = NM_DEVICE_STATE_REASON_CONFIG_FAILED;

            return NM_ACT_STAGE_RETURN_FAILURE;

        }

    }

    return NM_ACT_STAGE_RETURN_SUCCESS;

}

static void

unrealize_notify(NMDevice *device)

{

    NM_DEVICE_CLASS(nm_device_tun_parent_class)->unrealize_notify(device);

    update_properties_from_struct(NM_DEVICE_TUN(device), NULL);

}

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

static void

get_property(GObject *object, guint prop_id, GValue *value, GParamSpec *pspec)

{

    NMDeviceTun *       self = NM_DEVICE_TUN(object);

    NMDeviceTunPrivate *priv = NM_DEVICE_TUN_GET_PRIVATE(self);

    const char *        s;

    switch (prop_id) {

    case PROP_OWNER:

        g_value_set_int64(value,

                          priv->props.owner_valid ? (gint64) priv->props.owner : (gint64) -1);

        break;

    case PROP_GROUP:

        g_value_set_int64(value,

                          priv->props.group_valid ? (gint64) priv->props.group : (gint64) -1);

        break;

    case PROP_MODE:

        switch (priv->props.type) {

        case IFF_TUN:

            s = "tun";

            break;

        case IFF_TAP:

            s = "tap";

            break;

        default:

            s = NULL;

            break;

        }

        g_value_set_static_string(value, s);

        break;

    case PROP_NO_PI:

        g_value_set_boolean(value, !priv->props.pi);

        break;

    case PROP_VNET_HDR:

        g_value_set_boolean(value, priv->props.vnet_hdr);

        break;

    case PROP_MULTI_QUEUE:

        g_value_set_boolean(value, priv->props.multi_queue);

        break;

    default:

        G_OBJECT_WARN_INVALID_PROPERTY_ID(object, prop_id, pspec);

        break;

    }

}

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

static void

nm_device_tun_init(NMDeviceTun *self)

{}

static const NMDBusInterfaceInfoExtended interface_info_device_tun = {

    .parent = NM_DEFINE_GDBUS_INTERFACE_INFO_INIT(

        NM_DBUS_INTERFACE_DEVICE_TUN,

        .signals    = NM_DEFINE_GDBUS_SIGNAL_INFOS(&nm_signal_info_property_changed_legacy, ),

        .properties = NM_DEFINE_GDBUS_PROPERTY_INFOS(

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("Owner", "x", NM_DEVICE_TUN_OWNER),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("Group", "x", NM_DEVICE_TUN_GROUP),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("Mode", "s", NM_DEVICE_TUN_MODE),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("NoPi", "b", NM_DEVICE_TUN_NO_PI),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("VnetHdr",

                                                             "b",

                                                             NM_DEVICE_TUN_VNET_HDR),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("MultiQueue",

                                                             "b",

                                                             NM_DEVICE_TUN_MULTI_QUEUE),

            NM_DEFINE_DBUS_PROPERTY_INFO_EXTENDED_READABLE_L("HwAddress",

                                                             "s",

                                                             NM_DEVICE_HW_ADDRESS), ), ),

    .legacy_property_changed = TRUE,

};

static void

nm_device_tun_class_init(NMDeviceTunClass *klass)

{

    GObjectClass *     object_class      = G_OBJECT_CLASS(klass);

    NMDBusObjectClass *dbus_object_class = NM_DBUS_OBJECT_CLASS(klass);

    NMDeviceClass *    device_class      = NM_DEVICE_CLASS(klass);

    object_class->get_property = get_property;

    dbus_object_class->interface_infos = NM_DBUS_INTERFACE_INFOS(&interface_info_device_tun);

    device_class->connection_type_supported        = NM_SETTING_TUN_SETTING_NAME;

    device_class->connection_type_check_compatible = NM_SETTING_TUN_SETTING_NAME;

    device_class->link_types                       = NM_DEVICE_DEFINE_LINK_TYPES(NM_LINK_TYPE_TUN);

    device_class->link_changed                = link_changed;

    device_class->complete_connection         = complete_connection;

    device_class->check_connection_compatible = check_connection_compatible;

    device_class->create_and_realize          = create_and_realize;

    device_class->get_generic_capabilities    = get_generic_capabilities;

    device_class->unrealize_notify            = unrealize_notify;

    device_class->update_connection           = update_connection;

    device_class->act_stage1_prepare          = act_stage1_prepare;

    device_class->get_configured_mtu          = nm_device_get_configured_mtu_for_wired;

    obj_properties[PROP_OWNER] = g_param_spec_int64(NM_DEVICE_TUN_OWNER,

                                                    "",

                                                    "",

                                                    -1,

                                                    G_MAXUINT32,

                                                    -1,

                                                    G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    obj_properties[PROP_GROUP] = g_param_spec_int64(NM_DEVICE_TUN_GROUP,

                                                    "",

                                                    "",

                                                    -1,

                                                    G_MAXUINT32,

                                                    -1,

                                                    G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    obj_properties[PROP_MODE] = g_param_spec_string(NM_DEVICE_TUN_MODE,

                                                    "",

                                                    "",

                                                    NULL,

                                                    G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    obj_properties[PROP_NO_PI] = g_param_spec_boolean(NM_DEVICE_TUN_NO_PI,

                                                      "",

                                                      "",

                                                      FALSE,

                                                      G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    obj_properties[PROP_VNET_HDR] = g_param_spec_boolean(NM_DEVICE_TUN_VNET_HDR,

                                                         "",

                                                         "",

                                                         FALSE,

                                                         G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    obj_properties[PROP_MULTI_QUEUE] =

        g_param_spec_boolean(NM_DEVICE_TUN_MULTI_QUEUE,

                             "",

                             "",

                             FALSE,

                             G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);

    g_object_class_install_properties(object_class, _PROPERTY_ENUMS_LAST, obj_properties);

}

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

#define NM_TYPE_TUN_DEVICE_FACTORY (nm_tun_device_factory_get_type())

#define NM_TUN_DEVICE_FACTORY(obj) \

    (G_TYPE_CHECK_INSTANCE_CAST((obj), NM_TYPE_TUN_DEVICE_FACTORY, NMTunDeviceFactory))

static NMDevice *

create_device(NMDeviceFactory *     factory,

              const char *          iface,

              const NMPlatformLink *plink,

              NMConnection *        connection,

              gboolean *            out_ignore)

{

    g_return_val_if_fail(!plink || plink->type == NM_LINK_TYPE_TUN, NULL);

    g_return_val_if_fail(!connection

                             || nm_streq0(nm_connection_get_connection_type(connection),

                                          NM_SETTING_TUN_SETTING_NAME),

                         NULL);

    return g_object_new(NM_TYPE_DEVICE_TUN,

                        NM_DEVICE_IFACE,

                        iface,

                        NM_DEVICE_TYPE_DESC,

                        "Tun",

                        NM_DEVICE_DEVICE_TYPE,

                        NM_DEVICE_TYPE_TUN,

                        NM_DEVICE_LINK_TYPE,

                        (guint) NM_LINK_TYPE_TUN,

                        NULL);

}

NM_DEVICE_FACTORY_DEFINE_INTERNAL(

    TUN,

    Tun,

    tun,

    NM_DEVICE_FACTORY_DECLARE_LINK_TYPES(NM_LINK_TYPE_TUN)

        NM_DEVICE_FACTORY_DECLARE_SETTING_TYPES(NM_SETTING_TUN_SETTING_NAME),

    factory_class->create_device = create_device;);