net/ipv4/netfilter/iptable_raw.c

   1 /*
   2  * 'raw' table, which is the very first hooked in at PRE_ROUTING and LOCAL_OUT .
   3  *
   4  * Copyright (C) 2003 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
   5  */
   6 #include <linux/module.h>
   7 #include <linux/netfilter_ipv4/ip_tables.h>
   8
   9 #define RAW_VALID_HOOKS ((1 << NF_IP_PRE_ROUTING) | (1 << NF_IP_LOCAL_OUT))
  10
  11 static struct
  12 {
  13         struct ipt_replace repl;
  14         struct ipt_standard entries[2];
  15         struct ipt_error term;
  16 } initial_table __initdata = {
  17         .repl = {
  18                 .name = "raw",
  19                 .valid_hooks = RAW_VALID_HOOKS,
  20                 .num_entries = 3,
  21                 .size = sizeof(struct ipt_standard) * 2 + sizeof(struct ipt_error),
  22                 .hook_entry = {
  23                         [NF_IP_PRE_ROUTING] = 0,
  24                         [NF_IP_LOCAL_OUT] = sizeof(struct ipt_standard)
  25                 },
  26                 .underflow = {
  27                         [NF_IP_PRE_ROUTING] = 0,
  28                         [NF_IP_LOCAL_OUT]  = sizeof(struct ipt_standard)
  29                 },
  30         },
  31         .entries = {
  32                 IPT_STANDARD_INIT(NF_ACCEPT),   /* PRE_ROUTING */
  33                 IPT_STANDARD_INIT(NF_ACCEPT),   /* LOCAL_OUT */
  34         },
  35         .term = IPT_ERROR_INIT,                 /* ERROR */
  36 };
  37
  38 static struct xt_table packet_raw = {
  39         .name = "raw",
  40         .valid_hooks =  RAW_VALID_HOOKS,
  41         .lock = RW_LOCK_UNLOCKED,
  42         .me = THIS_MODULE,
  43         .af = AF_INET,
  44 };
  45
  46 /* The work comes in here from netfilter.c. */
  47 static unsigned int
  48 ipt_hook(unsigned int hook,
  49          struct sk_buff **pskb,
  50          const struct net_device *in,
  51          const struct net_device *out,
  52          int (*okfn)(struct sk_buff *))
  53 {
  54         return ipt_do_table(pskb, hook, in, out, &packet_raw);
  55 }
  56
  57 /* 'raw' is the very first table. */
  58 static struct nf_hook_ops ipt_ops[] = {
  59         {
  60                 .hook = ipt_hook,
  61                 .pf = PF_INET,
  62                 .hooknum = NF_IP_PRE_ROUTING,
  63                 .priority = NF_IP_PRI_RAW,
  64                 .owner = THIS_MODULE,
  65         },
  66         {
  67                 .hook = ipt_hook,
  68                 .pf = PF_INET,
  69                 .hooknum = NF_IP_LOCAL_OUT,
  70                 .priority = NF_IP_PRI_RAW,
  71                 .owner = THIS_MODULE,
  72         },
  73 };
  74
  75 static int __init iptable_raw_init(void)
  76 {
  77         int ret;
  78
  79         /* Register table */
  80         ret = ipt_register_table(&packet_raw, &initial_table.repl);
  81         if (ret < 0)
  82                 return ret;
  83
  84         /* Register hooks */
  85         ret = nf_register_hooks(ipt_ops, ARRAY_SIZE(ipt_ops));
  86         if (ret < 0)
  87                 goto cleanup_table;
  88
  89         return ret;
  90
  91  cleanup_table:
  92         ipt_unregister_table(&packet_raw);
  93         return ret;
  94 }
  95
  96 static void __exit iptable_raw_fini(void)
  97 {
  98         nf_unregister_hooks(ipt_ops, ARRAY_SIZE(ipt_ops));
  99         ipt_unregister_table(&packet_raw);
 100 }
 101
 102 module_init(iptable_raw_init);
 103 module_exit(iptable_raw_fini);
 104 MODULE_LICENSE("GPL");