[NET]: Supporting UDP-Lite (RFC 3828) in Linux
[linux-2.6.git] / net / ipv4 / udplite.c
1 /*
2  *  UDPLITE     An implementation of the UDP-Lite protocol (RFC 3828).
3  *
4  *  Version:    $Id: udplite.c,v 1.25 2006/10/19 07:22:36 gerrit Exp $
5  *
6  *  Authors:    Gerrit Renker       <gerrit@erg.abdn.ac.uk>
7  *
8  *  Changes:
9  *  Fixes:
10  *              This program is free software; you can redistribute it and/or
11  *              modify it under the terms of the GNU General Public License
12  *              as published by the Free Software Foundation; either version
13  *              2 of the License, or (at your option) any later version.
14  */
15 #include "udp_impl.h"
16 DEFINE_SNMP_STAT(struct udp_mib, udplite_statistics)    __read_mostly;
17
18 struct hlist_head       udplite_hash[UDP_HTABLE_SIZE];
19 static int              udplite_port_rover;
20
21 __inline__ int udplite_get_port(struct sock *sk, unsigned short p,
22                         int (*c)(const struct sock *, const struct sock *))
23 {
24         return  __udp_lib_get_port(sk, p, udplite_hash, &udplite_port_rover, c);
25 }
26
27 static __inline__ int udplite_v4_get_port(struct sock *sk, unsigned short snum)
28 {
29         return udplite_get_port(sk, snum, ipv4_rcv_saddr_equal);
30 }
31
32 __inline__ int udplite_rcv(struct sk_buff *skb)
33 {
34         return __udp4_lib_rcv(skb, udplite_hash, 1);
35 }
36
37 __inline__ void udplite_err(struct sk_buff *skb, u32 info)
38 {
39         return __udp4_lib_err(skb, info, udplite_hash);
40 }
41
42 static  struct net_protocol udplite_protocol = {
43         .handler        = udplite_rcv,
44         .err_handler    = udplite_err,
45         .no_policy      = 1,
46 };
47
48 struct proto    udplite_prot = {
49         .name              = "UDP-Lite",
50         .owner             = THIS_MODULE,
51         .close             = udp_lib_close,
52         .connect           = ip4_datagram_connect,
53         .disconnect        = udp_disconnect,
54         .ioctl             = udp_ioctl,
55         .init              = udplite_sk_init,
56         .destroy           = udp_destroy_sock,
57         .setsockopt        = udp_setsockopt,
58         .getsockopt        = udp_getsockopt,
59         .sendmsg           = udp_sendmsg,
60         .recvmsg           = udp_recvmsg,
61         .sendpage          = udp_sendpage,
62         .backlog_rcv       = udp_queue_rcv_skb,
63         .hash              = udp_lib_hash,
64         .unhash            = udp_lib_unhash,
65         .get_port          = udplite_v4_get_port,
66         .obj_size          = sizeof(struct udp_sock),
67 #ifdef CONFIG_COMPAT
68         .compat_setsockopt = compat_udp_setsockopt,
69         .compat_getsockopt = compat_udp_getsockopt,
70 #endif
71 };
72
73 static struct inet_protosw udplite4_protosw = {
74         .type           =  SOCK_DGRAM,
75         .protocol       =  IPPROTO_UDPLITE,
76         .prot           =  &udplite_prot,
77         .ops            =  &inet_dgram_ops,
78         .capability     = -1,
79         .no_check       =  0,           /* must checksum (RFC 3828) */
80         .flags          =  INET_PROTOSW_PERMANENT,
81 };
82
83 #ifdef CONFIG_PROC_FS
84 static struct file_operations udplite4_seq_fops;
85 static struct udp_seq_afinfo udplite4_seq_afinfo = {
86         .owner          = THIS_MODULE,
87         .name           = "udplite",
88         .family         = AF_INET,
89         .hashtable      = udplite_hash,
90         .seq_show       = udp4_seq_show,
91         .seq_fops       = &udplite4_seq_fops,
92 };
93 #endif
94
95 void __init udplite4_register(void)
96 {
97         if (proto_register(&udplite_prot, 1))
98                 goto out_register_err;
99
100         if (inet_add_protocol(&udplite_protocol, IPPROTO_UDPLITE) < 0)
101                 goto out_unregister_proto;
102
103         inet_register_protosw(&udplite4_protosw);
104
105 #ifdef CONFIG_PROC_FS
106         if (udp_proc_register(&udplite4_seq_afinfo)) /* udplite4_proc_init() */
107                 printk(KERN_ERR "%s: Cannot register /proc!\n", __FUNCTION__);
108 #endif
109         return;
110
111 out_unregister_proto:
112         proto_unregister(&udplite_prot);
113 out_register_err:
114         printk(KERN_CRIT "%s: Cannot add UDP-Lite protocol.\n", __FUNCTION__);
115 }
116
117 EXPORT_SYMBOL(udplite_hash);
118 EXPORT_SYMBOL(udplite_prot);
119 EXPORT_SYMBOL(udplite_get_port);