net/ipv4/udplite.c

   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
  22 static int udplite_rcv(struct sk_buff *skb)
  23 {
  24         return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
  25 }
  26
  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
  97 static int __net_init udplite4_proc_init_net(struct net *net)
  98 {
  99         return udp_proc_register(net, &udplite4_seq_afinfo);
 100 }
 101
 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
 112 static __init int udplite4_proc_init(void)
 113 {
 114         return register_pernet_subsys(&udplite4_net_ops);
 115 }
 116 #else
 117 static inline int udplite4_proc_init(void)
 118 {
 119         return 0;
 120 }
 121 #endif
 122
 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 }