// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  UDPLITEv6   An implementation of the UDP-Lite protocol over IPv6.
 *              See also net/ipv4/udplite.c
 *
 *  Authors:    Gerrit Renker       <gerrit@erg.abdn.ac.uk>
 *
 *  Changes:
 *  Fixes:
 */
#define pr_fmt(fmt) "UDPLite6: " fmt

#include <linux/export.h>
#include <linux/proc_fs.h>
#include "udp_impl.h"

static int udplitev6_sk_init(struct sock *sk)
{
        pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, "
                     "please contact the netdev mailing list\n");
        return udpv6_init_sock(sk);
}

static int udplitev6_rcv(struct sk_buff *skb)
{
        return __udp6_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
}

static int udplitev6_err(struct sk_buff *skb,
                          struct inet6_skb_parm *opt,
                          u8 type, u8 code, int offset, __be32 info)
{
        return __udp6_lib_err(skb, opt, type, code, offset, info,
                              &udplite_table);
}

static const struct inet6_protocol udplitev6_protocol = {
        .handler        =       udplitev6_rcv,
        .err_handler    =       udplitev6_err,
        .flags          =       INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};

struct proto udplitev6_prot = {
        .name              = "UDPLITEv6",
        .owner             = THIS_MODULE,
        .close             = udp_lib_close,
        .connect           = ip6_datagram_connect,
        .disconnect        = udp_disconnect,
        .ioctl             = udp_ioctl,
        .init              = udplitev6_sk_init,
        .destroy           = udpv6_destroy_sock,
        .setsockopt        = udpv6_setsockopt,
        .getsockopt        = udpv6_getsockopt,
        .sendmsg           = udpv6_sendmsg,
        .recvmsg           = udpv6_recvmsg,
        .hash              = udp_lib_hash,
        .unhash            = udp_lib_unhash,
        .rehash            = udp_v6_rehash,
        .get_port          = udp_v6_get_port,

        .memory_allocated  = &net_aligned_data.udp_memory_allocated,
        .per_cpu_fw_alloc  = &udp_memory_per_cpu_fw_alloc,

        .sysctl_mem        = sysctl_udp_mem,
        .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
        .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
        .obj_size          = sizeof(struct udp6_sock),
        .ipv6_pinfo_offset = offsetof(struct udp6_sock, inet6),
        .h.udp_table       = &udplite_table,
};

static struct inet_protosw udplite6_protosw = {
        .type           = SOCK_DGRAM,
        .protocol       = IPPROTO_UDPLITE,
        .prot           = &udplitev6_prot,
        .ops            = &inet6_dgram_ops,
        .flags          = INET_PROTOSW_PERMANENT,
};

int __init udplitev6_init(void)
{
        int ret;

        ret = inet6_add_protocol(&udplitev6_protocol, IPPROTO_UDPLITE);
        if (ret)
                goto out;

        ret = inet6_register_protosw(&udplite6_protosw);
        if (ret)
                goto out_udplitev6_protocol;
out:
        return ret;

out_udplitev6_protocol:
        inet6_del_protocol(&udplitev6_protocol, IPPROTO_UDPLITE);
        goto out;
}

void udplitev6_exit(void)
{
        inet6_unregister_protosw(&udplite6_protosw);
        inet6_del_protocol(&udplitev6_protocol, IPPROTO_UDPLITE);
}

#ifdef CONFIG_PROC_FS
static struct udp_seq_afinfo udplite6_seq_afinfo = {
        .family         = AF_INET6,
        .udp_table      = &udplite_table,
};

static int __net_init udplite6_proc_init_net(struct net *net)
{
        if (!proc_create_net_data("udplite6", 0444, net->proc_net,
                        &udp6_seq_ops, sizeof(struct udp_iter_state),
                        &udplite6_seq_afinfo))
                return -ENOMEM;
        return 0;
}

static void __net_exit udplite6_proc_exit_net(struct net *net)
{
        remove_proc_entry("udplite6", net->proc_net);
}

static struct pernet_operations udplite6_net_ops = {
        .init = udplite6_proc_init_net,
        .exit = udplite6_proc_exit_net,
};

int __init udplite6_proc_init(void)
{
        return register_pernet_subsys(&udplite6_net_ops);
}

void udplite6_proc_exit(void)
{
        unregister_pernet_subsys(&udplite6_net_ops);
}
#endif