udplite.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  UDPLITE     An implementation of the UDP-Lite protocol (RFC 3828).
  4 *
  5 *  Authors:    Gerrit Renker       <gerrit@erg.abdn.ac.uk>
  6 *
  7 *  Changes:
  8 *  Fixes:
  9 */
 10
 11#define pr_fmt(fmt) "UDPLite: " fmt
 12
 13#include <linux/export.h>
 14#include <linux/proc_fs.h>
 15#include "udp_impl.h"
 16
 17struct udp_table 	udplite_table __read_mostly;
 18EXPORT_SYMBOL(udplite_table);
 19
 20/* Designate sk as UDP-Lite socket */
 21static int udplite_sk_init(struct sock *sk)
 22{
 23	pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, "
 24		     "please contact the netdev mailing list\n");
 25	return udp_init_sock(sk);
 26}
 27
 28static int udplite_rcv(struct sk_buff *skb)
 29{
 30	return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
 31}
 32
 33static int udplite_err(struct sk_buff *skb, u32 info)
 34{
 35	return __udp4_lib_err(skb, info, &udplite_table);
 36}
 37
 38static const struct net_protocol udplite_protocol = {
 39	.handler	= udplite_rcv,
 40	.err_handler	= udplite_err,
 41	.no_policy	= 1,
 42};
 43
 44struct proto 	udplite_prot = {
 45	.name		   = "UDP-Lite",
 46	.owner		   = THIS_MODULE,
 47	.close		   = udp_lib_close,
 48	.connect	   = ip4_datagram_connect,
 49	.disconnect	   = udp_disconnect,
 50	.ioctl		   = udp_ioctl,
 51	.init		   = udplite_sk_init,
 52	.destroy	   = udp_destroy_sock,
 53	.setsockopt	   = udp_setsockopt,
 54	.getsockopt	   = udp_getsockopt,
 55	.sendmsg	   = udp_sendmsg,
 56	.recvmsg	   = udp_recvmsg,
 57	.hash		   = udp_lib_hash,
 58	.unhash		   = udp_lib_unhash,
 59	.rehash		   = udp_v4_rehash,
 60	.get_port	   = udp_v4_get_port,
 61
 62	.memory_allocated  = &net_aligned_data.udp_memory_allocated,
 63	.per_cpu_fw_alloc  = &udp_memory_per_cpu_fw_alloc,
 64
 65	.sysctl_mem	   = sysctl_udp_mem,
 66	.sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
 67	.sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
 68	.obj_size	   = sizeof(struct udp_sock),
 69	.h.udp_table	   = &udplite_table,
 70};
 71EXPORT_SYMBOL(udplite_prot);
 72
 73static struct inet_protosw udplite4_protosw = {
 74	.type		=  SOCK_DGRAM,
 75	.protocol	=  IPPROTO_UDPLITE,
 76	.prot		=  &udplite_prot,
 77	.ops		=  &inet_dgram_ops,
 78	.flags		=  INET_PROTOSW_PERMANENT,
 79};
 80
 81#ifdef CONFIG_PROC_FS
 82static struct udp_seq_afinfo udplite4_seq_afinfo = {
 83	.family		= AF_INET,
 84	.udp_table 	= &udplite_table,
 85};
 86
 87static int __net_init udplite4_proc_init_net(struct net *net)
 88{
 89	if (!proc_create_net_data("udplite", 0444, net->proc_net, &udp_seq_ops,
 90			sizeof(struct udp_iter_state), &udplite4_seq_afinfo))
 91		return -ENOMEM;
 92	return 0;
 93}
 94
 95static void __net_exit udplite4_proc_exit_net(struct net *net)
 96{
 97	remove_proc_entry("udplite", net->proc_net);
 98}
 99
100static struct pernet_operations udplite4_net_ops = {
101	.init = udplite4_proc_init_net,
102	.exit = udplite4_proc_exit_net,
103};
104
105static __init int udplite4_proc_init(void)
106{
107	return register_pernet_subsys(&udplite4_net_ops);
108}
109#else
110static inline int udplite4_proc_init(void)
111{
112	return 0;
113}
114#endif
115
116void __init udplite4_register(void)
117{
118	udp_table_init(&udplite_table, "UDP-Lite");
119	if (proto_register(&udplite_prot, 1))
120		goto out_register_err;
121
122	if (inet_add_protocol(&udplite_protocol, IPPROTO_UDPLITE) < 0)
123		goto out_unregister_proto;
124
125	inet_register_protosw(&udplite4_protosw);
126
127	if (udplite4_proc_init())
128		pr_err("%s: Cannot register /proc!\n", __func__);
129	return;
130
131out_unregister_proto:
132	proto_unregister(&udplite_prot);
133out_register_err:
134	pr_crit("%s: Cannot add UDP-Lite protocol\n", __func__);
135}