net/bridge/netfilter/ebt_mark_m.c

   1 /*
   2  *  ebt_mark_m
   3  *
   4  *      Authors:
   5  *      Bart De Schuymer <bdschuym@pandora.be>
   6  *
   7  *  July, 2002
   8  *
   9  */
  10
  11 #include <linux/netfilter_bridge/ebtables.h>
  12 #include <linux/netfilter_bridge/ebt_mark_m.h>
  13 #include <linux/module.h>
  14
  15 static int ebt_filter_mark(const struct sk_buff *skb,
  16    const struct net_device *in, const struct net_device *out, const void *data,
  17    unsigned int datalen)
  18 {
  19         struct ebt_mark_m_info *info = (struct ebt_mark_m_info *) data;
  20
  21         if (info->bitmask & EBT_MARK_OR)
  22                 return !(!!(skb->nfmark & info->mask) ^ info->invert);
  23         return !(((skb->nfmark & info->mask) == info->mark) ^ info->invert);
  24 }
  25
  26 static int ebt_mark_check(const char *tablename, unsigned int hookmask,
  27    const struct ebt_entry *e, void *data, unsigned int datalen)
  28 {
  29         struct ebt_mark_m_info *info = (struct ebt_mark_m_info *) data;
  30
  31         if (datalen != EBT_ALIGN(sizeof(struct ebt_mark_m_info)))
  32                 return -EINVAL;
  33         if (info->bitmask & ~EBT_MARK_MASK)
  34                 return -EINVAL;
  35         if ((info->bitmask & EBT_MARK_OR) && (info->bitmask & EBT_MARK_AND))
  36                 return -EINVAL;
  37         if (!info->bitmask)
  38                 return -EINVAL;
  39         return 0;
  40 }
  41
  42 static struct ebt_match filter_mark =
  43 {
  44         .name           = EBT_MARK_MATCH,
  45         .match          = ebt_filter_mark,
  46         .check          = ebt_mark_check,
  47         .me             = THIS_MODULE,
  48 };
  49
  50 static int __init init(void)
  51 {
  52         return ebt_register_match(&filter_mark);
  53 }
  54
  55 static void __exit fini(void)
  56 {
  57         ebt_unregister_match(&filter_mark);
  58 }
  59
  60 module_init(init);
  61 module_exit(fini);
  62 MODULE_LICENSE("GPL");