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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* This module is used to copy security markings from packets
* to connections, and restore security markings from connections
* back to packets. This would normally be performed in conjunction
* with the SECMARK target and state match.
*
* Based somewhat on CONNMARK:
* Copyright (C) 2002,2004 MARA Systems AB <https://www.marasystems.com>
* by Henrik Nordstrom <hno@marasystems.com>
*
* (C) 2006,2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_CONNSECMARK.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_ecache.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
MODULE_DESCRIPTION("Xtables: target for copying between connection and security mark");
MODULE_ALIAS("ipt_CONNSECMARK");
MODULE_ALIAS("ip6t_CONNSECMARK");
/*
* If the packet has a security mark and the connection does not, copy
* the security mark from the packet to the connection.
*/
static void secmark_save(const struct sk_buff *skb)
{
if (skb->secmark) {
struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
ct = nf_ct_get(skb, &ctinfo);
if (ct && !ct->secmark) {
ct->secmark = skb->secmark;
nf_conntrack_event_cache(IPCT_SECMARK, ct);
}
}
}
/*
* If packet has no security mark, and the connection does, restore the
* security mark from the connection to the packet.
*/
static void secmark_restore(struct sk_buff *skb)
{
if (!skb->secmark) {
const struct nf_conn *ct;
enum ip_conntrack_info ctinfo;
ct = nf_ct_get(skb, &ctinfo);
if (ct && ct->secmark)
skb->secmark = ct->secmark;
}
}
static unsigned int
connsecmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
const struct xt_connsecmark_target_info *info = par->targinfo;
switch (info->mode) {
case CONNSECMARK_SAVE:
secmark_save(skb);
break;
case CONNSECMARK_RESTORE:
secmark_restore(skb);
break;
default:
BUG();
}
return XT_CONTINUE;
}
static int connsecmark_tg_check(const struct xt_tgchk_param *par)
{
const struct xt_connsecmark_target_info *info = par->targinfo;
int ret;
if (strcmp(par->table, "mangle") != 0 &&
strcmp(par->table, "security") != 0) {
pr_info_ratelimited("only valid in \'mangle\' or \'security\' table, not \'%s\'\n",
par->table);
return -EINVAL;
}
switch (info->mode) {
case CONNSECMARK_SAVE:
case CONNSECMARK_RESTORE:
break;
default:
pr_info_ratelimited("invalid mode: %hu\n", info->mode);
return -EINVAL;
}
ret = nf_ct_netns_get(par->net, par->family);
if (ret < 0)
pr_info_ratelimited("cannot load conntrack support for proto=%u\n",
par->family);
return ret;
}
static void connsecmark_tg_destroy(const struct xt_tgdtor_param *par)
{
nf_ct_netns_put(par->net, par->family);
}
static struct xt_target connsecmark_tg_reg __read_mostly = {
.name = "CONNSECMARK",
.revision = 0,
.family = NFPROTO_UNSPEC,
.checkentry = connsecmark_tg_check,
.destroy = connsecmark_tg_destroy,
.target = connsecmark_tg,
.targetsize = sizeof(struct xt_connsecmark_target_info),
.me = THIS_MODULE,
};
static int __init connsecmark_tg_init(void)
{
return xt_register_target(&connsecmark_tg_reg);
}
static void __exit connsecmark_tg_exit(void)
{
xt_unregister_target(&connsecmark_tg_reg);
}
module_init(connsecmark_tg_init);
module_exit(connsecmark_tg_exit);
|
