root/net/bridge/netfilter/ebt_mark_m.c

DEFINITIONS

1. ebt_mark_mt
2. ebt_mark_mt_check
3. mark_mt_compat_from_user
4. mark_mt_compat_to_user
5. ebt_mark_m_init
6. ebt_mark_m_fini

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  ebt_mark_m
   4  *
   5  *      Authors:
   6  *      Bart De Schuymer <bdschuym@pandora.be>
   7  *
   8  *  July, 2002
   9  *
  10  */
  11 #include <linux/module.h>
  12 #include <linux/netfilter/x_tables.h>
  13 #include <linux/netfilter_bridge/ebtables.h>
  14 #include <linux/netfilter_bridge/ebt_mark_m.h>
  15 
  16 static bool
  17 ebt_mark_mt(const struct sk_buff *skb, struct xt_action_param *par)
  18 {
  19         const struct ebt_mark_m_info *info = par->matchinfo;
  20 
  21         if (info->bitmask & EBT_MARK_OR)
  22                 return !!(skb->mark & info->mask) ^ info->invert;
  23         return ((skb->mark & info->mask) == info->mark) ^ info->invert;
  24 }
  25 
  26 static int ebt_mark_mt_check(const struct xt_mtchk_param *par)
  27 {
  28         const struct ebt_mark_m_info *info = par->matchinfo;
  29 
  30         if (info->bitmask & ~EBT_MARK_MASK)
  31                 return -EINVAL;
  32         if ((info->bitmask & EBT_MARK_OR) && (info->bitmask & EBT_MARK_AND))
  33                 return -EINVAL;
  34         if (!info->bitmask)
  35                 return -EINVAL;
  36         return 0;
  37 }
  38 
  39 
  40 #ifdef CONFIG_COMPAT
  41 struct compat_ebt_mark_m_info {
  42         compat_ulong_t mark, mask;
  43         uint8_t invert, bitmask;
  44 };
  45 
  46 static void mark_mt_compat_from_user(void *dst, const void *src)
  47 {
  48         const struct compat_ebt_mark_m_info *user = src;
  49         struct ebt_mark_m_info *kern = dst;
  50 
  51         kern->mark = user->mark;
  52         kern->mask = user->mask;
  53         kern->invert = user->invert;
  54         kern->bitmask = user->bitmask;
  55 }
  56 
  57 static int mark_mt_compat_to_user(void __user *dst, const void *src)
  58 {
  59         struct compat_ebt_mark_m_info __user *user = dst;
  60         const struct ebt_mark_m_info *kern = src;
  61 
  62         if (put_user(kern->mark, &user->mark) ||
  63             put_user(kern->mask, &user->mask) ||
  64             put_user(kern->invert, &user->invert) ||
  65             put_user(kern->bitmask, &user->bitmask))
  66                 return -EFAULT;
  67         return 0;
  68 }
  69 #endif
  70 
  71 static struct xt_match ebt_mark_mt_reg __read_mostly = {
  72         .name           = "mark_m",
  73         .revision       = 0,
  74         .family         = NFPROTO_BRIDGE,
  75         .match          = ebt_mark_mt,
  76         .checkentry     = ebt_mark_mt_check,
  77         .matchsize      = sizeof(struct ebt_mark_m_info),
  78 #ifdef CONFIG_COMPAT
  79         .compatsize     = sizeof(struct compat_ebt_mark_m_info),
  80         .compat_from_user = mark_mt_compat_from_user,
  81         .compat_to_user = mark_mt_compat_to_user,
  82 #endif
  83         .me             = THIS_MODULE,
  84 };
  85 
  86 static int __init ebt_mark_m_init(void)
  87 {
  88         return xt_register_match(&ebt_mark_mt_reg);
  89 }
  90 
  91 static void __exit ebt_mark_m_fini(void)
  92 {
  93         xt_unregister_match(&ebt_mark_mt_reg);
  94 }
  95 
  96 module_init(ebt_mark_m_init);
  97 module_exit(ebt_mark_m_fini);
  98 MODULE_DESCRIPTION("Ebtables: Packet mark match");
  99 MODULE_LICENSE("GPL");