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 udp_init_sock(sk);
24 pr_warn_once("UDP-Lite is deprecated and scheduled to be removed in 2025, "
25 "please contact the netdev mailing list\n");
26 return 0;
27}
28
29static int udplite_rcv(struct sk_buff *skb)
30{
31 return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
32}
33
34static int udplite_err(struct sk_buff *skb, u32 info)
35{
36 return __udp4_lib_err(skb, info, &udplite_table);
37}
38
39static const struct net_protocol udplite_protocol = {
40 .handler = udplite_rcv,
41 .err_handler = udplite_err,
42 .no_policy = 1,
43};
44
45struct proto udplite_prot = {
46 .name = "UDP-Lite",
47 .owner = THIS_MODULE,
48 .close = udp_lib_close,
49 .connect = ip4_datagram_connect,
50 .disconnect = udp_disconnect,
51 .ioctl = udp_ioctl,
52 .init = udplite_sk_init,
53 .destroy = udp_destroy_sock,
54 .setsockopt = udp_setsockopt,
55 .getsockopt = udp_getsockopt,
56 .sendmsg = udp_sendmsg,
57 .recvmsg = udp_recvmsg,
58 .hash = udp_lib_hash,
59 .unhash = udp_lib_unhash,
60 .rehash = udp_v4_rehash,
61 .get_port = udp_v4_get_port,
62
63 .memory_allocated = &net_aligned_data.udp_memory_allocated,
64 .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc,
65
66 .sysctl_mem = sysctl_udp_mem,
67 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
68 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
69 .obj_size = sizeof(struct udp_sock),
70 .h.udp_table = &udplite_table,
71};
72EXPORT_SYMBOL(udplite_prot);
73
74static struct inet_protosw udplite4_protosw = {
75 .type = SOCK_DGRAM,
76 .protocol = IPPROTO_UDPLITE,
77 .prot = &udplite_prot,
78 .ops = &inet_dgram_ops,
79 .flags = INET_PROTOSW_PERMANENT,
80};
81
82#ifdef CONFIG_PROC_FS
83static struct udp_seq_afinfo udplite4_seq_afinfo = {
84 .family = AF_INET,
85 .udp_table = &udplite_table,
86};
87
88static int __net_init udplite4_proc_init_net(struct net *net)
89{
90 if (!proc_create_net_data(name: "udplite", mode: 0444, parent: net->proc_net, ops: &udp_seq_ops,
91 state_size: sizeof(struct udp_iter_state), data: &udplite4_seq_afinfo))
92 return -ENOMEM;
93 return 0;
94}
95
96static void __net_exit udplite4_proc_exit_net(struct net *net)
97{
98 remove_proc_entry("udplite", net->proc_net);
99}
100
101static struct pernet_operations udplite4_net_ops = {
102 .init = udplite4_proc_init_net,
103 .exit = udplite4_proc_exit_net,
104};
105
106static __init int udplite4_proc_init(void)
107{
108 return register_pernet_subsys(&udplite4_net_ops);
109}
110#else
111static inline int udplite4_proc_init(void)
112{
113 return 0;
114}
115#endif
116
117void __init udplite4_register(void)
118{
119 udp_table_init(&udplite_table, "UDP-Lite");
120 if (proto_register(prot: &udplite_prot, alloc_slab: 1))
121 goto out_register_err;
122
123 if (inet_add_protocol(prot: &udplite_protocol, IPPROTO_UDPLITE) < 0)
124 goto out_unregister_proto;
125
126 inet_register_protosw(p: &udplite4_protosw);
127
128 if (udplite4_proc_init())
129 pr_err("%s: Cannot register /proc!\n", __func__);
130 return;
131
132out_unregister_proto:
133 proto_unregister(prot: &udplite_prot);
134out_register_err:
135 pr_crit("%s: Cannot add UDP-Lite protocol\n", __func__);
136}
137