net/ipv4/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
  17 struct udp_table        udplite_table __read_mostly;
  18 EXPORT_SYMBOL(udplite_table);
  19
  20 /* Designate sk as UDP-Lite socket */
  21 static int udplite_sk_init(struct sock *sk)
  22 {
  23         udp_init_sock(sk);
  24         udp_sk(sk)->pcflag = UDPLITE_BIT;
  25         return 0;
  26 }
  27
  28 static int udplite_rcv(struct sk_buff *skb)
  29 {
  30         return __udp4_lib_rcv(skb, &udplite_table, IPPROTO_UDPLITE);
  31 }
  32
  33 static int udplite_err(struct sk_buff *skb, u32 info)
  34 {
  35         return __udp4_lib_err(skb, info, &udplite_table);
  36 }
  37
  38 static const struct net_protocol udplite_protocol = {
  39         .handler        = udplite_rcv,
  40         .err_handler    = udplite_err,
  41         .no_policy      = 1,
  42 };
  43
  44 struct 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         .sendpage          = udp_sendpage,
  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  = &udp_memory_allocated,
  64         .per_cpu_fw_alloc  = &udp_memory_per_cpu_fw_alloc,
  65
  66         .sysctl_mem        = sysctl_udp_mem,
  67         .obj_size          = sizeof(struct udp_sock),
  68         .h.udp_table       = &udplite_table,
  69 };
  70 EXPORT_SYMBOL(udplite_prot);
  71
  72 static struct inet_protosw udplite4_protosw = {
  73         .type           =  SOCK_DGRAM,
  74         .protocol       =  IPPROTO_UDPLITE,
  75         .prot           =  &udplite_prot,
  76         .ops            =  &inet_dgram_ops,
  77         .flags          =  INET_PROTOSW_PERMANENT,
  78 };
  79
  80 #ifdef CONFIG_PROC_FS
  81 static struct udp_seq_afinfo udplite4_seq_afinfo = {
  82         .family         = AF_INET,
  83         .udp_table      = &udplite_table,
  84 };
  85
  86 static int __net_init udplite4_proc_init_net(struct net *net)
  87 {
  88         if (!proc_create_net_data("udplite", 0444, net->proc_net, &udp_seq_ops,
  89                         sizeof(struct udp_iter_state), &udplite4_seq_afinfo))
  90                 return -ENOMEM;
  91         return 0;
  92 }
  93
  94 static void __net_exit udplite4_proc_exit_net(struct net *net)
  95 {
  96         remove_proc_entry("udplite", net->proc_net);
  97 }
  98
  99 static struct pernet_operations udplite4_net_ops = {
 100         .init = udplite4_proc_init_net,
 101         .exit = udplite4_proc_exit_net,
 102 };
 103
 104 static __init int udplite4_proc_init(void)
 105 {
 106         return register_pernet_subsys(&udplite4_net_ops);
 107 }
 108 #else
 109 static inline int udplite4_proc_init(void)
 110 {
 111         return 0;
 112 }
 113 #endif
 114
 115 void __init udplite4_register(void)
 116 {
 117         udp_table_init(&udplite_table, "UDP-Lite");
 118         if (proto_register(&udplite_prot, 1))
 119                 goto out_register_err;
 120
 121         if (inet_add_protocol(&udplite_protocol, IPPROTO_UDPLITE) < 0)
 122                 goto out_unregister_proto;
 123
 124         inet_register_protosw(&udplite4_protosw);
 125
 126         if (udplite4_proc_init())
 127                 pr_err("%s: Cannot register /proc!\n", __func__);
 128         return;
 129
 130 out_unregister_proto:
 131         proto_unregister(&udplite_prot);
 132 out_register_err:
 133         pr_crit("%s: Cannot add UDP-Lite protocol\n", __func__);
 134 }