Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 1 | /* x_tables module for setting the IPv4/IPv6 DSCP field, Version 1.8 |
| 2 | * |
| 3 | * (C) 2002 by Harald Welte <laforge@netfilter.org> |
| 4 | * based on ipt_FTOS.c (C) 2000 by Matthew G. Marsh <mgm@paktronix.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * See RFC2474 for a description of the DSCP field within the IP Header. |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 11 | */ |
Jan Engelhardt | 8bee4ba | 2010-03-17 16:04:40 +0100 | [diff] [blame] | 12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 13 | #include <linux/module.h> |
| 14 | #include <linux/skbuff.h> |
| 15 | #include <linux/ip.h> |
| 16 | #include <linux/ipv6.h> |
| 17 | #include <net/dsfield.h> |
| 18 | |
| 19 | #include <linux/netfilter/x_tables.h> |
| 20 | #include <linux/netfilter/xt_DSCP.h> |
| 21 | |
| 22 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
Jan Engelhardt | 2ae15b6 | 2008-01-14 23:42:28 -0800 | [diff] [blame] | 23 | MODULE_DESCRIPTION("Xtables: DSCP/TOS field modification"); |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 24 | MODULE_LICENSE("GPL"); |
| 25 | MODULE_ALIAS("ipt_DSCP"); |
| 26 | MODULE_ALIAS("ip6t_DSCP"); |
Jan Engelhardt | c9fd496 | 2007-12-04 23:38:13 -0800 | [diff] [blame] | 27 | MODULE_ALIAS("ipt_TOS"); |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 28 | MODULE_ALIAS("ip6t_TOS"); |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 29 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 30 | static unsigned int |
Jan Engelhardt | 4b560b4 | 2009-07-05 19:43:26 +0200 | [diff] [blame] | 31 | dscp_tg(struct sk_buff *skb, const struct xt_action_param *par) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 32 | { |
Jan Engelhardt | 7eb3558 | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 33 | const struct xt_DSCP_info *dinfo = par->targinfo; |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 34 | u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT; |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 35 | |
| 36 | if (dscp != dinfo->dscp) { |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 37 | if (!skb_make_writable(skb, sizeof(struct iphdr))) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 38 | return NF_DROP; |
| 39 | |
Florian Westphal | 5676864 | 2014-11-13 10:04:16 +0100 | [diff] [blame] | 40 | ipv4_change_dsfield(ip_hdr(skb), |
| 41 | (__force __u8)(~XT_DSCP_MASK), |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 42 | dinfo->dscp << XT_DSCP_SHIFT); |
| 43 | |
| 44 | } |
| 45 | return XT_CONTINUE; |
| 46 | } |
| 47 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 48 | static unsigned int |
Jan Engelhardt | 4b560b4 | 2009-07-05 19:43:26 +0200 | [diff] [blame] | 49 | dscp_tg6(struct sk_buff *skb, const struct xt_action_param *par) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 50 | { |
Jan Engelhardt | 7eb3558 | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 51 | const struct xt_DSCP_info *dinfo = par->targinfo; |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 52 | u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT; |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 53 | |
| 54 | if (dscp != dinfo->dscp) { |
Herbert Xu | 3db05fe | 2007-10-15 00:53:15 -0700 | [diff] [blame] | 55 | if (!skb_make_writable(skb, sizeof(struct ipv6hdr))) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 56 | return NF_DROP; |
| 57 | |
Florian Westphal | 5676864 | 2014-11-13 10:04:16 +0100 | [diff] [blame] | 58 | ipv6_change_dsfield(ipv6_hdr(skb), |
| 59 | (__force __u8)(~XT_DSCP_MASK), |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 60 | dinfo->dscp << XT_DSCP_SHIFT); |
| 61 | } |
| 62 | return XT_CONTINUE; |
| 63 | } |
| 64 | |
Jan Engelhardt | 135367b | 2010-03-19 17:16:42 +0100 | [diff] [blame] | 65 | static int dscp_tg_check(const struct xt_tgchk_param *par) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 66 | { |
Jan Engelhardt | af5d6dc | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 67 | const struct xt_DSCP_info *info = par->targinfo; |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 68 | |
Jan Engelhardt | af5d6dc | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 69 | if (info->dscp > XT_DSCP_MAX) { |
Jan Engelhardt | 8bee4ba | 2010-03-17 16:04:40 +0100 | [diff] [blame] | 70 | pr_info("dscp %x out of range\n", info->dscp); |
Jan Engelhardt | 4a5a5c7 | 2010-03-19 17:32:59 +0100 | [diff] [blame] | 71 | return -EDOM; |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 72 | } |
Jan Engelhardt | d6b00a5 | 2010-03-25 16:34:45 +0100 | [diff] [blame] | 73 | return 0; |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 74 | } |
| 75 | |
Jan Engelhardt | c9fd496 | 2007-12-04 23:38:13 -0800 | [diff] [blame] | 76 | static unsigned int |
Jan Engelhardt | 4b560b4 | 2009-07-05 19:43:26 +0200 | [diff] [blame] | 77 | tos_tg(struct sk_buff *skb, const struct xt_action_param *par) |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 78 | { |
Jan Engelhardt | 7eb3558 | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 79 | const struct xt_tos_target_info *info = par->targinfo; |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 80 | struct iphdr *iph = ip_hdr(skb); |
| 81 | u_int8_t orig, nv; |
| 82 | |
| 83 | orig = ipv4_get_dsfield(iph); |
Jan Engelhardt | 9bb268e | 2008-01-14 23:32:37 -0800 | [diff] [blame] | 84 | nv = (orig & ~info->tos_mask) ^ info->tos_value; |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 85 | |
| 86 | if (orig != nv) { |
| 87 | if (!skb_make_writable(skb, sizeof(struct iphdr))) |
| 88 | return NF_DROP; |
| 89 | iph = ip_hdr(skb); |
Jan Engelhardt | cdfe8b9 | 2008-01-14 23:32:54 -0800 | [diff] [blame] | 90 | ipv4_change_dsfield(iph, 0, nv); |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 91 | } |
| 92 | |
| 93 | return XT_CONTINUE; |
| 94 | } |
| 95 | |
| 96 | static unsigned int |
Jan Engelhardt | 4b560b4 | 2009-07-05 19:43:26 +0200 | [diff] [blame] | 97 | tos_tg6(struct sk_buff *skb, const struct xt_action_param *par) |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 98 | { |
Jan Engelhardt | 7eb3558 | 2008-10-08 11:35:19 +0200 | [diff] [blame] | 99 | const struct xt_tos_target_info *info = par->targinfo; |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 100 | struct ipv6hdr *iph = ipv6_hdr(skb); |
| 101 | u_int8_t orig, nv; |
| 102 | |
| 103 | orig = ipv6_get_dsfield(iph); |
Fernando Luis Vazquez Cao | 1ed2f73 | 2011-05-10 10:00:21 +0200 | [diff] [blame] | 104 | nv = (orig & ~info->tos_mask) ^ info->tos_value; |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 105 | |
| 106 | if (orig != nv) { |
| 107 | if (!skb_make_writable(skb, sizeof(struct iphdr))) |
| 108 | return NF_DROP; |
| 109 | iph = ipv6_hdr(skb); |
Jan Engelhardt | cdfe8b9 | 2008-01-14 23:32:54 -0800 | [diff] [blame] | 110 | ipv6_change_dsfield(iph, 0, nv); |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 111 | } |
| 112 | |
| 113 | return XT_CONTINUE; |
| 114 | } |
| 115 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 116 | static struct xt_target dscp_tg_reg[] __read_mostly = { |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 117 | { |
| 118 | .name = "DSCP", |
Jan Engelhardt | ee999d8 | 2008-10-08 11:35:01 +0200 | [diff] [blame] | 119 | .family = NFPROTO_IPV4, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 120 | .checkentry = dscp_tg_check, |
| 121 | .target = dscp_tg, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 122 | .targetsize = sizeof(struct xt_DSCP_info), |
| 123 | .table = "mangle", |
| 124 | .me = THIS_MODULE, |
| 125 | }, |
| 126 | { |
| 127 | .name = "DSCP", |
Jan Engelhardt | ee999d8 | 2008-10-08 11:35:01 +0200 | [diff] [blame] | 128 | .family = NFPROTO_IPV6, |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 129 | .checkentry = dscp_tg_check, |
| 130 | .target = dscp_tg6, |
Patrick McHardy | 4470bbc | 2006-08-22 00:34:04 -0700 | [diff] [blame] | 131 | .targetsize = sizeof(struct xt_DSCP_info), |
| 132 | .table = "mangle", |
| 133 | .me = THIS_MODULE, |
| 134 | }, |
Jan Engelhardt | c9fd496 | 2007-12-04 23:38:13 -0800 | [diff] [blame] | 135 | { |
| 136 | .name = "TOS", |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 137 | .revision = 1, |
Jan Engelhardt | ee999d8 | 2008-10-08 11:35:01 +0200 | [diff] [blame] | 138 | .family = NFPROTO_IPV4, |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 139 | .table = "mangle", |
| 140 | .target = tos_tg, |
| 141 | .targetsize = sizeof(struct xt_tos_target_info), |
| 142 | .me = THIS_MODULE, |
| 143 | }, |
| 144 | { |
| 145 | .name = "TOS", |
| 146 | .revision = 1, |
Jan Engelhardt | ee999d8 | 2008-10-08 11:35:01 +0200 | [diff] [blame] | 147 | .family = NFPROTO_IPV6, |
Jan Engelhardt | 5c350e5 | 2007-12-04 23:39:09 -0800 | [diff] [blame] | 148 | .table = "mangle", |
| 149 | .target = tos_tg6, |
| 150 | .targetsize = sizeof(struct xt_tos_target_info), |
| 151 | .me = THIS_MODULE, |
| 152 | }, |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 153 | }; |
| 154 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 155 | static int __init dscp_tg_init(void) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 156 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 157 | return xt_register_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg)); |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 158 | } |
| 159 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 160 | static void __exit dscp_tg_exit(void) |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 161 | { |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 162 | xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg)); |
Yasuyuki Kozakai | a468701 | 2006-08-22 00:30:26 -0700 | [diff] [blame] | 163 | } |
| 164 | |
Jan Engelhardt | d3c5ee6 | 2007-12-04 23:24:03 -0800 | [diff] [blame] | 165 | module_init(dscp_tg_init); |
| 166 | module_exit(dscp_tg_exit); |