summaryrefslogtreecommitdiff
path: root/net/netfilter/xt_MARK.c
blob: 67574bcfb8ac8016e65d211ce6126806a157f229 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
/*
 *	xt_MARK - Netfilter module to modify the NFMARK field of an skb
 *
 *	(C) 1999-2001 Marc Boucher <marc@mbsi.ca>
 *	Copyright © CC Computer Consultants GmbH, 2007 - 2008
 *	Jan Engelhardt <jengelh@computergmbh.de>
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2 as
 *	published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <net/checksum.h>

#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_MARK.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
MODULE_DESCRIPTION("Xtables: packet mark modification");
MODULE_ALIAS("ipt_MARK");
MODULE_ALIAS("ip6t_MARK");

static unsigned int
mark_tg_v0(struct sk_buff *skb, const struct xt_target_param *par)
{
	const struct xt_mark_target_info *markinfo = par->targinfo;

	skb->mark = markinfo->mark;
	return XT_CONTINUE;
}

static unsigned int
mark_tg_v1(struct sk_buff *skb, const struct xt_target_param *par)
{
	const struct xt_mark_target_info_v1 *markinfo = par->targinfo;
	int mark = 0;

	switch (markinfo->mode) {
	case XT_MARK_SET:
		mark = markinfo->mark;
		break;

	case XT_MARK_AND:
		mark = skb->mark & markinfo->mark;
		break;

	case XT_MARK_OR:
		mark = skb->mark | markinfo->mark;
		break;
	}

	skb->mark = mark;
	return XT_CONTINUE;
}

static unsigned int
mark_tg(struct sk_buff *skb, const struct xt_target_param *par)
{
	const struct xt_mark_tginfo2 *info = par->targinfo;

	skb->mark = (skb->mark & ~info->mask) ^ info->mark;
	return XT_CONTINUE;
}

static bool mark_tg_check_v0(const struct xt_tgchk_param *par)
{
	const struct xt_mark_target_info *markinfo = par->targinfo;

	if (markinfo->mark > 0xffffffff) {
		printk(KERN_WARNING "MARK: Only supports 32bit wide mark\n");
		return false;
	}
	return true;
}

static bool mark_tg_check_v1(const struct xt_tgchk_param *par)
{
	const struct xt_mark_target_info_v1 *markinfo = par->targinfo;

	if (markinfo->mode != XT_MARK_SET
	    && markinfo->mode != XT_MARK_AND
	    && markinfo->mode != XT_MARK_OR) {
		printk(KERN_WARNING "MARK: unknown mode %u\n",
		       markinfo->mode);
		return false;
	}
	if (markinfo->mark > 0xffffffff) {
		printk(KERN_WARNING "MARK: Only supports 32bit wide mark\n");
		return false;
	}
	return true;
}

#ifdef CONFIG_COMPAT
struct compat_xt_mark_target_info {
	compat_ulong_t	mark;
};

static void mark_tg_compat_from_user_v0(void *dst, void *src)
{
	const struct compat_xt_mark_target_info *cm = src;
	struct xt_mark_target_info m = {
		.mark	= cm->mark,
	};
	memcpy(dst, &m, sizeof(m));
}

static int mark_tg_compat_to_user_v0(void __user *dst, void *src)
{
	const struct xt_mark_target_info *m = src;
	struct compat_xt_mark_target_info cm = {
		.mark	= m->mark,
	};
	return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}

struct compat_xt_mark_target_info_v1 {
	compat_ulong_t	mark;
	u_int8_t	mode;
	u_int8_t	__pad1;
	u_int16_t	__pad2;
};

static void mark_tg_compat_from_user_v1(void *dst, void *src)
{
	const struct compat_xt_mark_target_info_v1 *cm = src;
	struct xt_mark_target_info_v1 m = {
		.mark	= cm->mark,
		.mode	= cm->mode,
	};
	memcpy(dst, &m, sizeof(m));
}

static int mark_tg_compat_to_user_v1(void __user *dst, void *src)
{
	const struct xt_mark_target_info_v1 *m = src;
	struct compat_xt_mark_target_info_v1 cm = {
		.mark	= m->mark,
		.mode	= m->mode,
	};
	return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}
#endif /* CONFIG_COMPAT */

static struct xt_target mark_tg_reg[] __read_mostly = {
	{
		.name		= "MARK",
		.family		= NFPROTO_UNSPEC,
		.revision	= 0,
		.checkentry	= mark_tg_check_v0,
		.target		= mark_tg_v0,
		.targetsize	= sizeof(struct xt_mark_target_info),
#ifdef CONFIG_COMPAT
		.compatsize	= sizeof(struct compat_xt_mark_target_info),
		.compat_from_user = mark_tg_compat_from_user_v0,
		.compat_to_user	= mark_tg_compat_to_user_v0,
#endif
		.table		= "mangle",
		.me		= THIS_MODULE,
	},
	{
		.name		= "MARK",
		.family		= NFPROTO_UNSPEC,
		.revision	= 1,
		.checkentry	= mark_tg_check_v1,
		.target		= mark_tg_v1,
		.targetsize	= sizeof(struct xt_mark_target_info_v1),
#ifdef CONFIG_COMPAT
		.compatsize	= sizeof(struct compat_xt_mark_target_info_v1),
		.compat_from_user = mark_tg_compat_from_user_v1,
		.compat_to_user	= mark_tg_compat_to_user_v1,
#endif
		.table		= "mangle",
		.me		= THIS_MODULE,
	},
	{
		.name           = "MARK",
		.revision       = 2,
		.family         = NFPROTO_UNSPEC,
		.target         = mark_tg,
		.targetsize     = sizeof(struct xt_mark_tginfo2),
		.me             = THIS_MODULE,
	},
};

static int __init mark_tg_init(void)
{
	return xt_register_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
}

static void __exit mark_tg_exit(void)
{
	xt_unregister_targets(mark_tg_reg, ARRAY_SIZE(mark_tg_reg));
}

module_init(mark_tg_init);
module_exit(mark_tg_exit);