1 /*
2  *  UDPLITE     An implementation of the UDP-Lite protocol (RFC 3828).
3  *
4  *  Authors:    Gerrit Renker       <gerrit@erg.abdn.ac.uk>
5  *
6  *  Changes:
7  *  Fixes:
8  *		This program is free software; you can redistribute it and/or
9  *		modify it under the terms of the GNU General Public License
10  *		as published by the Free Software Foundation; either version
11  *		2 of the License, or (at your option) any later version.
12  */
13 
14 #define pr_fmt(fmt) "UDPLite: " fmt
15 
16 #include <linux/export.h>
17 #include "udp_impl.h"
18 
19 struct udp_table 	udplite_table __read_mostly;
20 EXPORT_SYMBOL(udplite_table);
21 
udplite_rcv(struct sk_buff * skb)22 static int udplite_rcv(struct sk_buff *skb)
23 {
24 	return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
25 }
26 
udplite_err(struct sk_buff * skb,u32 info)27 static void udplite_err(struct sk_buff *skb, u32 info)
28 {
29 	__udp4_lib_err(skb, info, &udplite_table);
30 }
31 
32 static const struct net_protocol udplite_protocol = {
33 	.handler	= udplite_rcv,
34 	.err_handler	= udplite_err,
35 	.no_policy	= 1,
36 	.netns_ok	= 1,
37 };
38 
39 struct proto 	udplite_prot = {
40 	.name		   = "UDP-Lite",
41 	.owner		   = THIS_MODULE,
42 	.close		   = udp_lib_close,
43 	.connect	   = ip4_datagram_connect,
44 	.disconnect	   = udp_disconnect,
45 	.ioctl		   = udp_ioctl,
46 	.init		   = udplite_sk_init,
47 	.destroy	   = udp_destroy_sock,
48 	.setsockopt	   = udp_setsockopt,
49 	.getsockopt	   = udp_getsockopt,
50 	.sendmsg	   = udp_sendmsg,
51 	.recvmsg	   = udp_recvmsg,
52 	.sendpage	   = udp_sendpage,
53 	.backlog_rcv	   = udp_queue_rcv_skb,
54 	.hash		   = udp_lib_hash,
55 	.unhash		   = udp_lib_unhash,
56 	.get_port	   = udp_v4_get_port,
57 	.obj_size	   = sizeof(struct udp_sock),
58 	.slab_flags	   = SLAB_DESTROY_BY_RCU,
59 	.h.udp_table	   = &udplite_table,
60 #ifdef CONFIG_COMPAT
61 	.compat_setsockopt = compat_udp_setsockopt,
62 	.compat_getsockopt = compat_udp_getsockopt,
63 #endif
64 	.clear_sk	   = sk_prot_clear_portaddr_nulls,
65 };
66 EXPORT_SYMBOL(udplite_prot);
67 
68 static struct inet_protosw udplite4_protosw = {
69 	.type		=  SOCK_DGRAM,
70 	.protocol	=  IPPROTO_UDPLITE,
71 	.prot		=  &udplite_prot,
72 	.ops		=  &inet_dgram_ops,
73 	.no_check	=  0,		/* must checksum (RFC 3828) */
74 	.flags		=  INET_PROTOSW_PERMANENT,
75 };
76 
77 #ifdef CONFIG_PROC_FS
78 
79 static const struct file_operations udplite_afinfo_seq_fops = {
80 	.owner    = THIS_MODULE,
81 	.open     = udp_seq_open,
82 	.read     = seq_read,
83 	.llseek   = seq_lseek,
84 	.release  = seq_release_net
85 };
86 
87 static struct udp_seq_afinfo udplite4_seq_afinfo = {
88 	.name		= "udplite",
89 	.family		= AF_INET,
90 	.udp_table 	= &udplite_table,
91 	.seq_fops	= &udplite_afinfo_seq_fops,
92 	.seq_ops	= {
93 		.show		= udp4_seq_show,
94 	},
95 };
96 
udplite4_proc_init_net(struct net * net)97 static int __net_init udplite4_proc_init_net(struct net *net)
98 {
99 	return udp_proc_register(net, &udplite4_seq_afinfo);
100 }
101 
udplite4_proc_exit_net(struct net * net)102 static void __net_exit udplite4_proc_exit_net(struct net *net)
103 {
104 	udp_proc_unregister(net, &udplite4_seq_afinfo);
105 }
106 
107 static struct pernet_operations udplite4_net_ops = {
108 	.init = udplite4_proc_init_net,
109 	.exit = udplite4_proc_exit_net,
110 };
111 
udplite4_proc_init(void)112 static __init int udplite4_proc_init(void)
113 {
114 	return register_pernet_subsys(&udplite4_net_ops);
115 }
116 #else
udplite4_proc_init(void)117 static inline int udplite4_proc_init(void)
118 {
119 	return 0;
120 }
121 #endif
122 
udplite4_register(void)123 void __init udplite4_register(void)
124 {
125 	udp_table_init(&udplite_table, "UDP-Lite");
126 	if (proto_register(&udplite_prot, 1))
127 		goto out_register_err;
128 
129 	if (inet_add_protocol(&udplite_protocol, IPPROTO_UDPLITE) < 0)
130 		goto out_unregister_proto;
131 
132 	inet_register_protosw(&udplite4_protosw);
133 
134 	if (udplite4_proc_init())
135 		pr_err("%s: Cannot register /proc!\n", __func__);
136 	return;
137 
138 out_unregister_proto:
139 	proto_unregister(&udplite_prot);
140 out_register_err:
141 	pr_crit("%s: Cannot add UDP-Lite protocol\n", __func__);
142 }
143