1 /* 2 * ebt_mark 3 * 4 * Authors: 5 * Bart De Schuymer <bdschuym@pandora.be> 6 * 7 * July, 2002 8 * 9 */ 10 11 /* The mark target can be used in any chain, 12 * I believe adding a mangle table just for marking is total overkill. 13 * Marking a frame doesn't really change anything in the frame anyway. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/netfilter/x_tables.h> 18 #include <linux/netfilter_bridge/ebtables.h> 19 #include <linux/netfilter_bridge/ebt_mark_t.h> 20 21 static unsigned int 22 ebt_mark_tg(struct sk_buff *skb, const struct xt_action_param *par) 23 { 24 const struct ebt_mark_t_info *info = par->targinfo; 25 int action = info->target & -16; 26 27 if (action == MARK_SET_VALUE) 28 skb->mark = info->mark; 29 else if (action == MARK_OR_VALUE) 30 skb->mark |= info->mark; 31 else if (action == MARK_AND_VALUE) 32 skb->mark &= info->mark; 33 else 34 skb->mark ^= info->mark; 35 36 return info->target | ~EBT_VERDICT_BITS; 37 } 38 39 static int ebt_mark_tg_check(const struct xt_tgchk_param *par) 40 { 41 const struct ebt_mark_t_info *info = par->targinfo; 42 int tmp; 43 44 tmp = info->target | ~EBT_VERDICT_BITS; 45 if (BASE_CHAIN && tmp == EBT_RETURN) 46 return -EINVAL; 47 if (ebt_invalid_target(tmp)) 48 return -EINVAL; 49 tmp = info->target & ~EBT_VERDICT_BITS; 50 if (tmp != MARK_SET_VALUE && tmp != MARK_OR_VALUE && 51 tmp != MARK_AND_VALUE && tmp != MARK_XOR_VALUE) 52 return -EINVAL; 53 return 0; 54 } 55 #ifdef CONFIG_COMPAT 56 struct compat_ebt_mark_t_info { 57 compat_ulong_t mark; 58 compat_uint_t target; 59 }; 60 61 static void mark_tg_compat_from_user(void *dst, const void *src) 62 { 63 const struct compat_ebt_mark_t_info *user = src; 64 struct ebt_mark_t_info *kern = dst; 65 66 kern->mark = user->mark; 67 kern->target = user->target; 68 } 69 70 static int mark_tg_compat_to_user(void __user *dst, const void *src) 71 { 72 struct compat_ebt_mark_t_info __user *user = dst; 73 const struct ebt_mark_t_info *kern = src; 74 75 if (put_user(kern->mark, &user->mark) || 76 put_user(kern->target, &user->target)) 77 return -EFAULT; 78 return 0; 79 } 80 #endif 81 82 static struct xt_target ebt_mark_tg_reg __read_mostly = { 83 .name = "mark", 84 .revision = 0, 85 .family = NFPROTO_BRIDGE, 86 .target = ebt_mark_tg, 87 .checkentry = ebt_mark_tg_check, 88 .targetsize = sizeof(struct ebt_mark_t_info), 89 #ifdef CONFIG_COMPAT 90 .compatsize = sizeof(struct compat_ebt_mark_t_info), 91 .compat_from_user = mark_tg_compat_from_user, 92 .compat_to_user = mark_tg_compat_to_user, 93 #endif 94 .me = THIS_MODULE, 95 }; 96 97 static int __init ebt_mark_init(void) 98 { 99 return xt_register_target(&ebt_mark_tg_reg); 100 } 101 102 static void __exit ebt_mark_fini(void) 103 { 104 xt_unregister_target(&ebt_mark_tg_reg); 105 } 106 107 module_init(ebt_mark_init); 108 module_exit(ebt_mark_fini); 109 MODULE_DESCRIPTION("Ebtables: Packet mark modification"); 110 MODULE_LICENSE("GPL"); 111