// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2014 Nicira, Inc.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/in.h>
#include <linux/ip.h>
#include <linux/net.h>
#include <linux/rculist.h>
#include <linux/udp.h>
#include <linux/if_vlan.h>
#include <linux/module.h>

#include <net/geneve.h>
#include <net/icmp.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/udp.h>
#include <net/xfrm.h>

#include "datapath.h"
#include "vport.h"
#include "vport-netdev.h"

static struct vport_ops ovs_geneve_vport_ops;
/**
 * struct geneve_port - Keeps track of open UDP ports
 * @dst_port: destination port.
 */
struct geneve_port {
        u16 dst_port;
};

static inline struct geneve_port *geneve_vport(const struct vport *vport)
{
        return vport_priv(vport);
}

static int geneve_get_options(const struct vport *vport,
                              struct sk_buff *skb)
{
        struct geneve_port *geneve_port = geneve_vport(vport);

        if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, geneve_port->dst_port))
                return -EMSGSIZE;
        return 0;
}

static struct vport *geneve_tnl_create(const struct vport_parms *parms)
{
        struct net *net = ovs_dp_get_net(parms->dp);
        struct nlattr *options = parms->options;
        struct geneve_port *geneve_port;
        struct net_device *dev;
        struct vport *vport;
        struct nlattr *a;
        u16 dst_port;
        int err;

        if (!options) {
                err = -EINVAL;
                goto error;
        }

        a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
        if (a && nla_len(a) == sizeof(u16)) {
                dst_port = nla_get_u16(a);
        } else {
                /* Require destination port from userspace. */
                err = -EINVAL;
                goto error;
        }

        vport = ovs_vport_alloc(sizeof(struct geneve_port),
                                &ovs_geneve_vport_ops, parms);
        if (IS_ERR(vport))
                return vport;

        geneve_port = geneve_vport(vport);
        geneve_port->dst_port = dst_port;

        rtnl_lock();
        dev = geneve_dev_create_fb(net, parms->name, NET_NAME_USER, dst_port);
        if (IS_ERR(dev)) {
                rtnl_unlock();
                ovs_vport_free(vport);
                return ERR_CAST(dev);
        }

        err = dev_change_flags(dev, dev->flags | IFF_UP, NULL);
        if (err < 0) {
                rtnl_delete_link(dev, 0, NULL);
                rtnl_unlock();
                ovs_vport_free(vport);
                goto error;
        }

        rtnl_unlock();
        return vport;
error:
        return ERR_PTR(err);
}

static struct vport *geneve_create(const struct vport_parms *parms)
{
        struct vport *vport;

        vport = geneve_tnl_create(parms);
        if (IS_ERR(vport))
                return vport;

        return ovs_netdev_link(vport, parms->name);
}

static struct vport_ops ovs_geneve_vport_ops = {
        .type           = OVS_VPORT_TYPE_GENEVE,
        .create         = geneve_create,
        .destroy        = ovs_netdev_tunnel_destroy,
        .get_options    = geneve_get_options,
        .send           = dev_queue_xmit,
};

static int __init ovs_geneve_tnl_init(void)
{
        return ovs_vport_ops_register(&ovs_geneve_vport_ops);
}

static void __exit ovs_geneve_tnl_exit(void)
{
        ovs_vport_ops_unregister(&ovs_geneve_vport_ops);
}

module_init(ovs_geneve_tnl_init);
module_exit(ovs_geneve_tnl_exit);

MODULE_DESCRIPTION("OVS: Geneve switching port");
MODULE_LICENSE("GPL");
MODULE_ALIAS("vport-type-5");