net/ipv6/netfilter/ip6t_MARK.c

   1 /* This is a module which is used for setting the NFMARK field of an skb. */
   2
   3 /* (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/skbuff.h>
  12 #include <linux/ip.h>
  13 #include <net/checksum.h>
  14
  15 #include <linux/netfilter_ipv6/ip6_tables.h>
  16 #include <linux/netfilter_ipv6/ip6t_MARK.h>
  17
  18 MODULE_LICENSE("GPL");
  19 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
  20
  21 static unsigned int
  22 target(struct sk_buff **pskb,
  23        const struct net_device *in,
  24        const struct net_device *out,
  25        unsigned int hooknum,
  26        const void *targinfo,
  27        void *userinfo)
  28 {
  29         const struct ip6t_mark_target_info *markinfo = targinfo;
  30
  31         if((*pskb)->nfmark != markinfo->mark) {
  32                 (*pskb)->nfmark = markinfo->mark;
  33                 (*pskb)->nfcache |= NFC_ALTERED;
  34         }
  35         return IP6T_CONTINUE;
  36 }
  37
  38 static int
  39 checkentry(const char *tablename,
  40            const struct ip6t_entry *e,
  41            void *targinfo,
  42            unsigned int targinfosize,
  43            unsigned int hook_mask)
  44 {
  45         if (targinfosize != IP6T_ALIGN(sizeof(struct ip6t_mark_target_info))) {
  46                 printk(KERN_WARNING "MARK: targinfosize %u != %Zu\n",
  47                        targinfosize,
  48                        IP6T_ALIGN(sizeof(struct ip6t_mark_target_info)));
  49                 return 0;
  50         }
  51
  52         if (strcmp(tablename, "mangle") != 0) {
  53                 printk(KERN_WARNING "MARK: can only be called from \"mangle\" table, not \"%s\"\n", tablename);
  54                 return 0;
  55         }
  56
  57         return 1;
  58 }
  59
  60 static struct ip6t_target ip6t_mark_reg
  61 = { { NULL, NULL }, "MARK", target, checkentry, NULL, THIS_MODULE };
  62
  63 static int __init init(void)
  64 {
  65         printk(KERN_DEBUG "registering ipv6 mark target\n");
  66         if (ip6t_register_target(&ip6t_mark_reg))
  67                 return -EINVAL;
  68
  69         return 0;
  70 }
  71
  72 static void __exit fini(void)
  73 {
  74         ip6t_unregister_target(&ip6t_mark_reg);
  75 }
  76
  77 module_init(init);
  78 module_exit(fini);