netfilter: nf_log: fix sleeping function called from invalid context
[linux-2.6.git] / net / netfilter / xt_DSCP.c
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.
11 */
12
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 #include <linux/netfilter_ipv4/ipt_TOS.h>
22
23 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
24 MODULE_DESCRIPTION("Xtables: DSCP/TOS field modification");
25 MODULE_LICENSE("GPL");
26 MODULE_ALIAS("ipt_DSCP");
27 MODULE_ALIAS("ip6t_DSCP");
28 MODULE_ALIAS("ipt_TOS");
29 MODULE_ALIAS("ip6t_TOS");
30
31 static unsigned int
32 dscp_tg(struct sk_buff *skb, const struct xt_target_param *par)
33 {
34         const struct xt_DSCP_info *dinfo = par->targinfo;
35         u_int8_t dscp = ipv4_get_dsfield(ip_hdr(skb)) >> XT_DSCP_SHIFT;
36
37         if (dscp != dinfo->dscp) {
38                 if (!skb_make_writable(skb, sizeof(struct iphdr)))
39                         return NF_DROP;
40
41                 ipv4_change_dsfield(ip_hdr(skb), (__u8)(~XT_DSCP_MASK),
42                                     dinfo->dscp << XT_DSCP_SHIFT);
43
44         }
45         return XT_CONTINUE;
46 }
47
48 static unsigned int
49 dscp_tg6(struct sk_buff *skb, const struct xt_target_param *par)
50 {
51         const struct xt_DSCP_info *dinfo = par->targinfo;
52         u_int8_t dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> XT_DSCP_SHIFT;
53
54         if (dscp != dinfo->dscp) {
55                 if (!skb_make_writable(skb, sizeof(struct ipv6hdr)))
56                         return NF_DROP;
57
58                 ipv6_change_dsfield(ipv6_hdr(skb), (__u8)(~XT_DSCP_MASK),
59                                     dinfo->dscp << XT_DSCP_SHIFT);
60         }
61         return XT_CONTINUE;
62 }
63
64 static bool dscp_tg_check(const struct xt_tgchk_param *par)
65 {
66         const struct xt_DSCP_info *info = par->targinfo;
67
68         if (info->dscp > XT_DSCP_MAX) {
69                 printk(KERN_WARNING "DSCP: dscp %x out of range\n", info->dscp);
70                 return false;
71         }
72         return true;
73 }
74
75 static unsigned int
76 tos_tg_v0(struct sk_buff *skb, const struct xt_target_param *par)
77 {
78         const struct ipt_tos_target_info *info = par->targinfo;
79         struct iphdr *iph = ip_hdr(skb);
80         u_int8_t oldtos;
81
82         if ((iph->tos & IPTOS_TOS_MASK) != info->tos) {
83                 if (!skb_make_writable(skb, sizeof(struct iphdr)))
84                         return NF_DROP;
85
86                 iph      = ip_hdr(skb);
87                 oldtos   = iph->tos;
88                 iph->tos = (iph->tos & IPTOS_PREC_MASK) | info->tos;
89                 csum_replace2(&iph->check, htons(oldtos), htons(iph->tos));
90         }
91
92         return XT_CONTINUE;
93 }
94
95 static bool tos_tg_check_v0(const struct xt_tgchk_param *par)
96 {
97         const struct ipt_tos_target_info *info = par->targinfo;
98         const uint8_t tos = info->tos;
99
100         if (tos != IPTOS_LOWDELAY && tos != IPTOS_THROUGHPUT &&
101             tos != IPTOS_RELIABILITY && tos != IPTOS_MINCOST &&
102             tos != IPTOS_NORMALSVC) {
103                 printk(KERN_WARNING "TOS: bad tos value %#x\n", tos);
104                 return false;
105         }
106
107         return true;
108 }
109
110 static unsigned int
111 tos_tg(struct sk_buff *skb, const struct xt_target_param *par)
112 {
113         const struct xt_tos_target_info *info = par->targinfo;
114         struct iphdr *iph = ip_hdr(skb);
115         u_int8_t orig, nv;
116
117         orig = ipv4_get_dsfield(iph);
118         nv   = (orig & ~info->tos_mask) ^ info->tos_value;
119
120         if (orig != nv) {
121                 if (!skb_make_writable(skb, sizeof(struct iphdr)))
122                         return NF_DROP;
123                 iph = ip_hdr(skb);
124                 ipv4_change_dsfield(iph, 0, nv);
125         }
126
127         return XT_CONTINUE;
128 }
129
130 static unsigned int
131 tos_tg6(struct sk_buff *skb, const struct xt_target_param *par)
132 {
133         const struct xt_tos_target_info *info = par->targinfo;
134         struct ipv6hdr *iph = ipv6_hdr(skb);
135         u_int8_t orig, nv;
136
137         orig = ipv6_get_dsfield(iph);
138         nv   = (orig & info->tos_mask) ^ info->tos_value;
139
140         if (orig != nv) {
141                 if (!skb_make_writable(skb, sizeof(struct iphdr)))
142                         return NF_DROP;
143                 iph = ipv6_hdr(skb);
144                 ipv6_change_dsfield(iph, 0, nv);
145         }
146
147         return XT_CONTINUE;
148 }
149
150 static struct xt_target dscp_tg_reg[] __read_mostly = {
151         {
152                 .name           = "DSCP",
153                 .family         = NFPROTO_IPV4,
154                 .checkentry     = dscp_tg_check,
155                 .target         = dscp_tg,
156                 .targetsize     = sizeof(struct xt_DSCP_info),
157                 .table          = "mangle",
158                 .me             = THIS_MODULE,
159         },
160         {
161                 .name           = "DSCP",
162                 .family         = NFPROTO_IPV6,
163                 .checkentry     = dscp_tg_check,
164                 .target         = dscp_tg6,
165                 .targetsize     = sizeof(struct xt_DSCP_info),
166                 .table          = "mangle",
167                 .me             = THIS_MODULE,
168         },
169         {
170                 .name           = "TOS",
171                 .revision       = 0,
172                 .family         = NFPROTO_IPV4,
173                 .table          = "mangle",
174                 .target         = tos_tg_v0,
175                 .targetsize     = sizeof(struct ipt_tos_target_info),
176                 .checkentry     = tos_tg_check_v0,
177                 .me             = THIS_MODULE,
178         },
179         {
180                 .name           = "TOS",
181                 .revision       = 1,
182                 .family         = NFPROTO_IPV4,
183                 .table          = "mangle",
184                 .target         = tos_tg,
185                 .targetsize     = sizeof(struct xt_tos_target_info),
186                 .me             = THIS_MODULE,
187         },
188         {
189                 .name           = "TOS",
190                 .revision       = 1,
191                 .family         = NFPROTO_IPV6,
192                 .table          = "mangle",
193                 .target         = tos_tg6,
194                 .targetsize     = sizeof(struct xt_tos_target_info),
195                 .me             = THIS_MODULE,
196         },
197 };
198
199 static int __init dscp_tg_init(void)
200 {
201         return xt_register_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
202 }
203
204 static void __exit dscp_tg_exit(void)
205 {
206         xt_unregister_targets(dscp_tg_reg, ARRAY_SIZE(dscp_tg_reg));
207 }
208
209 module_init(dscp_tg_init);
210 module_exit(dscp_tg_exit);