Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 1 | /* IP tables module for matching the value of the IPv4/IPv6 DSCP field |
| 2 | * |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 3 | * (C) 2002 by Harald Welte <laforge@netfilter.org> |
| 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 <linux/ipv6.h> |
| 14 | #include <net/dsfield.h> |
| 15 | |
| 16 | #include <linux/netfilter/xt_dscp.h> |
| 17 | #include <linux/netfilter/x_tables.h> |
| 18 | |
| 19 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
| 20 | MODULE_DESCRIPTION("x_tables DSCP matching module"); |
| 21 | MODULE_LICENSE("GPL"); |
| 22 | MODULE_ALIAS("ipt_dscp"); |
| 23 | MODULE_ALIAS("ip6t_dscp"); |
| 24 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 25 | static bool |
| 26 | dscp_mt(const struct sk_buff *skb, const struct net_device *in, |
| 27 | const struct net_device *out, const struct xt_match *match, |
| 28 | const void *matchinfo, int offset, unsigned int protoff, bool *hotdrop) |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 29 | { |
| 30 | const struct xt_dscp_info *info = matchinfo; |
Jan Engelhardt | 1d93a9c | 2007-07-07 22:15:35 -0700 | [diff] [blame] | 31 | u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT; |
| 32 | |
| 33 | return (dscp == info->dscp) ^ !!info->invert; |
| 34 | } |
| 35 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 36 | static bool |
| 37 | dscp_mt6(const struct sk_buff *skb, const struct net_device *in, |
| 38 | const struct net_device *out, const struct xt_match *match, |
| 39 | const void *matchinfo, int offset, unsigned int protoff, |
| 40 | bool *hotdrop) |
Jan Engelhardt | 1d93a9c | 2007-07-07 22:15:35 -0700 | [diff] [blame] | 41 | { |
| 42 | const struct xt_dscp_info *info = matchinfo; |
Arnaldo Carvalho de Melo | 0660e03 | 2007-04-25 17:54:47 -0700 | [diff] [blame] | 43 | u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT; |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 44 | |
| 45 | return (dscp == info->dscp) ^ !!info->invert; |
| 46 | } |
| 47 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 48 | static bool |
| 49 | dscp_mt_check(const char *tablename, const void *info, |
| 50 | const struct xt_match *match, void *matchinfo, |
| 51 | unsigned int hook_mask) |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 52 | { |
| 53 | const u_int8_t dscp = ((struct xt_dscp_info *)matchinfo)->dscp; |
| 54 | |
| 55 | if (dscp > XT_DSCP_MAX) { |
| 56 | printk(KERN_ERR "xt_dscp: dscp %x out of range\n", dscp); |
Jan Engelhardt | ccb79bd | 2007-07-07 22:16:00 -0700 | [diff] [blame] | 57 | return false; |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 58 | } |
| 59 | |
Jan Engelhardt | ccb79bd | 2007-07-07 22:16:00 -0700 | [diff] [blame] | 60 | return true; |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 61 | } |
| 62 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 63 | static struct xt_match dscp_mt_reg[] __read_mostly = { |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 64 | { |
| 65 | .name = "dscp", |
| 66 | .family = AF_INET, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 67 | .checkentry = dscp_mt_check, |
| 68 | .match = dscp_mt, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 69 | .matchsize = sizeof(struct xt_dscp_info), |
| 70 | .me = THIS_MODULE, |
| 71 | }, |
| 72 | { |
| 73 | .name = "dscp", |
| 74 | .family = AF_INET6, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 75 | .checkentry = dscp_mt_check, |
| 76 | .match = dscp_mt6, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 77 | .matchsize = sizeof(struct xt_dscp_info), |
| 78 | .me = THIS_MODULE, |
| 79 | }, |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 80 | }; |
| 81 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 82 | static int __init dscp_mt_init(void) |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 83 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 84 | return xt_register_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg)); |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 85 | } |
| 86 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 87 | static void __exit dscp_mt_exit(void) |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 88 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 89 | xt_unregister_matches(dscp_mt_reg, ARRAY_SIZE(dscp_mt_reg)); |
Yasuyuki Kozakai | 9ba1627 | 2006-08-22 00:29:37 -0700 | [diff] [blame] | 90 | } |
| 91 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame^] | 92 | module_init(dscp_mt_init); |
| 93 | module_exit(dscp_mt_exit); |