1 // SPDX-License-Identifier: GPL-2.0-only
2 /* IP tables module for matching the value of the IPv4/IPv6 DSCP field
4 * (C) 2002 by Harald Welte <laforge@netfilter.org>
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 #include <linux/module.h>
8 #include <linux/skbuff.h>
10 #include <linux/ipv6.h>
11 #include <net/dsfield.h>
13 #include <linux/netfilter/x_tables.h>
14 #include <linux/netfilter/xt_dscp.h>
16 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
17 MODULE_DESCRIPTION("Xtables: DSCP/TOS field match");
18 MODULE_LICENSE("GPL");
19 MODULE_ALIAS("ipt_dscp");
20 MODULE_ALIAS("ip6t_dscp");
21 MODULE_ALIAS("ipt_tos");
22 MODULE_ALIAS("ip6t_tos");
25 dscp_mt(const struct sk_buff *skb, struct xt_action_param *par)
27 const struct xt_dscp_info *info = par->matchinfo;
28 u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT;
30 return (dscp == info->dscp) ^ !!info->invert;
34 dscp_mt6(const struct sk_buff *skb, struct xt_action_param *par)
36 const struct xt_dscp_info *info = par->matchinfo;
37 u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT;
39 return (dscp == info->dscp) ^ !!info->invert;
42 static int dscp_mt_check(const struct xt_mtchk_param *par)
44 const struct xt_dscp_info *info = par->matchinfo;
46 if (info->dscp > XT_DSCP_MAX)
52 static bool tos_mt(const struct sk_buff *skb, struct xt_action_param *par)
54 const struct xt_tos_match_info *info = par->matchinfo;
56 if (xt_family(par) == NFPROTO_IPV4)
57 return ((ip_hdr(skb)->tos & info->tos_mask) ==
58 info->tos_value) ^ !!info->invert;
60 return ((ipv6_get_dsfield(ipv6_hdr(skb)) & info->tos_mask) ==
61 info->tos_value) ^ !!info->invert;
64 static struct xt_match dscp_mt_reg[] __read_mostly = {
67 .family = NFPROTO_IPV4,
68 .checkentry = dscp_mt_check,
70 .matchsize = sizeof(struct xt_dscp_info),
75 .family = NFPROTO_IPV6,
76 .checkentry = dscp_mt_check,
78 .matchsize = sizeof(struct xt_dscp_info),
84 .family = NFPROTO_IPV4,
86 .matchsize = sizeof(struct xt_tos_match_info),
92 .family = NFPROTO_IPV6,
94 .matchsize = sizeof(struct xt_tos_match_info),
99 static int __init dscp_mt_init(void)
101 return xt_register_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg));
104 static void __exit dscp_mt_exit(void)
106 xt_unregister_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg));
109 module_init(dscp_mt_init);
110 module_exit(dscp_mt_exit);