net/ipv6/netfilter/ip6table_raw.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * IPv6 raw table, a port of the IPv4 raw table to IPv6
   4  *
   5  * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@netfilter.org>
   6  */
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8 #include <linux/module.h>
   9 #include <linux/netfilter_ipv6/ip6_tables.h>
  10 #include <linux/slab.h>
  11
  12 #define RAW_VALID_HOOKS ((1 << NF_INET_PRE_ROUTING) | (1 << NF_INET_LOCAL_OUT))
  13
  14 static bool raw_before_defrag __read_mostly;
  15 MODULE_PARM_DESC(raw_before_defrag, "Enable raw table before defrag");
  16 module_param(raw_before_defrag, bool, 0000);
  17
  18 static const struct xt_table packet_raw = {
  19         .name = "raw",
  20         .valid_hooks = RAW_VALID_HOOKS,
  21         .me = THIS_MODULE,
  22         .af = NFPROTO_IPV6,
  23         .priority = NF_IP6_PRI_RAW,
  24 };
  25
  26 static const struct xt_table packet_raw_before_defrag = {
  27         .name = "raw",
  28         .valid_hooks = RAW_VALID_HOOKS,
  29         .me = THIS_MODULE,
  30         .af = NFPROTO_IPV6,
  31         .priority = NF_IP6_PRI_RAW_BEFORE_DEFRAG,
  32 };
  33
  34 /* The work comes in here from netfilter.c. */
  35 static unsigned int
  36 ip6table_raw_hook(void *priv, struct sk_buff *skb,
  37                   const struct nf_hook_state *state)
  38 {
  39         return ip6t_do_table(skb, state, priv);
  40 }
  41
  42 static struct nf_hook_ops *rawtable_ops __read_mostly;
  43
  44 static int ip6table_raw_table_init(struct net *net)
  45 {
  46         struct ip6t_replace *repl;
  47         const struct xt_table *table = &packet_raw;
  48         int ret;
  49
  50         if (raw_before_defrag)
  51                 table = &packet_raw_before_defrag;
  52
  53         repl = ip6t_alloc_initial_table(table);
  54         if (repl == NULL)
  55                 return -ENOMEM;
  56         ret = ip6t_register_table(net, table, repl, rawtable_ops);
  57         kfree(repl);
  58         return ret;
  59 }
  60
  61 static void __net_exit ip6table_raw_net_pre_exit(struct net *net)
  62 {
  63         ip6t_unregister_table_pre_exit(net, "raw");
  64 }
  65
  66 static void __net_exit ip6table_raw_net_exit(struct net *net)
  67 {
  68         ip6t_unregister_table_exit(net, "raw");
  69 }
  70
  71 static struct pernet_operations ip6table_raw_net_ops = {
  72         .pre_exit = ip6table_raw_net_pre_exit,
  73         .exit = ip6table_raw_net_exit,
  74 };
  75
  76 static int __init ip6table_raw_init(void)
  77 {
  78         const struct xt_table *table = &packet_raw;
  79         int ret;
  80
  81         if (raw_before_defrag) {
  82                 table = &packet_raw_before_defrag;
  83                 pr_info("Enabling raw table before defrag\n");
  84         }
  85
  86         ret = xt_register_template(table, ip6table_raw_table_init);
  87         if (ret < 0)
  88                 return ret;
  89
  90         /* Register hooks */
  91         rawtable_ops = xt_hook_ops_alloc(table, ip6table_raw_hook);
  92         if (IS_ERR(rawtable_ops)) {
  93                 xt_unregister_template(table);
  94                 return PTR_ERR(rawtable_ops);
  95         }
  96
  97         ret = register_pernet_subsys(&ip6table_raw_net_ops);
  98         if (ret < 0) {
  99                 kfree(rawtable_ops);
 100                 xt_unregister_template(table);
 101                 return ret;
 102         }
 103
 104         return ret;
 105 }
 106
 107 static void __exit ip6table_raw_fini(void)
 108 {
 109         unregister_pernet_subsys(&ip6table_raw_net_ops);
 110         xt_unregister_template(&packet_raw);
 111         kfree(rawtable_ops);
 112 }
 113
 114 module_init(ip6table_raw_init);
 115 module_exit(ip6table_raw_fini);
 116 MODULE_LICENSE("GPL");